Merge pull request #854 from glmfe/master

bump(websocket): 1.4.0 -> 1.5.0

.github/workflows/mdns__host-tests.yml

@@ -24,7 +24,7 @@ jobs:
         shell: bash
         run: |
           . ${IDF_PATH}/export.sh
-          python -m pip install idf-build-apps dnspython pytest pytest-embedded pytest-embedded-serial-esp pytest-embedded-idf
+          python -m pip install idf-build-apps==2.10.0 dnspython pytest pytest-embedded pytest-embedded-serial-esp pytest-embedded-idf
           cd $GITHUB_WORKSPACE/protocols
           # Build host tests app (with all configs and targets supported)
           python ./ci/build_apps.py components/mdns/tests/host_test/

.github/workflows/modem__build-host-tests.yml

@@ -45,7 +45,7 @@ jobs:
     strategy:
       matrix:
         idf_ver: ["release-v5.0", "release-v5.1", "release-v5.2", "release-v5.3", "release-v5.4", "latest"]
-        test: ["target", "target_ota", "target_iperf"]
+        test: ["target", "target_ota", "target_iperf", "target_urc"]
 
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}

.github/workflows/modem_sim__build.yml

@@ -0,0 +1,28 @@
+name: "modem_sim: build-tests"
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types: [opened, synchronize, reopened, labeled]
+
+jobs:
+  build_modem_sim:
+    if: contains(github.event.pull_request.labels.*.name, 'modem_sim') || github.event_name == 'push'
+    name: Build
+    strategy:
+      matrix:
+        idf_ver: ["release-v5.4"]
+    runs-on: ubuntu-22.04
+    container: espressif/idf:${{ matrix.idf_ver }}
+    steps:
+      - name: Checkout esp-protocols
+        uses: actions/checkout@v3
+      - name: Build ESP-AT with IDF-${{ matrix.idf_ver }}
+        shell: bash
+        run: |
+          cd common_components/modem_sim
+          ./install.sh
+          source export.sh
+          idf.py build

.github/workflows/mosq__build.yml

@@ -13,11 +13,16 @@ jobs:
     name: Mosquitto build
     strategy:
       matrix:
-        idf_ver: ["latest", "release-v5.3"]
+        idf_ver: ["latest", "release-v5.5", "release-v5.4", "release-v5.3", "release-v5.2", "release-v5.1"]
+        example: ["broker", "serverless_mqtt"]
+        exclude:
+          - idf_ver: "release-v5.1"
+            example: "serverless_mqtt"  # serverless_mqtt is not supported due to esp-peer
+
     runs-on: ubuntu-22.04
     container: espressif/idf:${{ matrix.idf_ver }}
     env:
-      TEST_DIR: components/mosquitto/examples
+      TEST_DIR: components/mosquitto/examples/${{ matrix.example }}
       TARGET_TEST: broker
       TARGET_TEST_DIR: build_esp32_default
     steps:
@@ -31,14 +36,17 @@ jobs:
           . ${IDF_PATH}/export.sh
           pip install idf-component-manager idf-build-apps --upgrade
           python ci/build_apps.py -c ${TEST_DIR} -m components/mosquitto/.build-test-rules.yml
-          # upload only the target test artifacts
-          cd ${TEST_DIR}/${TARGET_TEST}
-          ${GITHUB_WORKSPACE}/ci/clean_build_artifacts.sh `pwd`/${TARGET_TEST_DIR}
-          zip -qur artifacts.zip ${TARGET_TEST_DIR}
+          if [ "${{ matrix.example }}" == "${TARGET_TEST}" ]; then
+            # upload only the target test artifacts
+            cd ${TEST_DIR}
+            ${GITHUB_WORKSPACE}/ci/clean_build_artifacts.sh `pwd`/${TARGET_TEST_DIR}
+            zip -qur artifacts.zip ${TARGET_TEST_DIR}
+          fi
       - uses: actions/upload-artifact@v4
+        if: ${{ matrix.example == 'broker' }}
         with:
           name: mosq_target_esp32_${{ matrix.idf_ver }}
-          path: ${{ env.TEST_DIR }}/${{ env.TARGET_TEST }}/artifacts.zip
+          path: ${{ env.TEST_DIR }}/artifacts.zip
           if-no-files-found: error
 
   test_mosq:

.gitignore

@@ -94,3 +94,9 @@ docs/html
 
 # esp-idf managed components
 **/managed_components/**
+
+# modem simulator uses esp-at clone
+common_components/modem_sim/modem_sim_esp32/
+
+# repository release tools
+release_notes.txt

.pre-commit-config.yaml

@@ -61,8 +61,8 @@ repos:
   - repo: local
     hooks:
       - id: commit message scopes
-        name: "commit message must be scoped with: mdns, dns, modem, websocket, asio, mqtt_cxx, console, common, eppp, tls_cxx, mosq, sockutls, lws"
-        entry: '\A(?!(feat|fix|ci|bump|test|docs|chore)\((mdns|dns|modem|common|console|websocket|asio|mqtt_cxx|examples|eppp|tls_cxx|mosq|sockutls|lws)\)\:)'
+        name: "commit message must be scoped with: mdns, dns, modem, websocket, asio, mqtt_cxx, console, common, eppp, tls_cxx, mosq, sockutls, lws, modem_sim"
+        entry: '\A(?!(feat|fix|ci|bump|test|docs|chore)\((mdns|dns|modem|common|console|websocket|asio|mqtt_cxx|examples|eppp|tls_cxx|mosq|sockutls|lws|modem_sim)\)\:)'
         language: pygrep
         args: [--multiline]
         stages: [commit-msg]

common_components/modem_sim/export.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+source $IDF_PATH/export.sh
+
+export AT_CUSTOM_COMPONENTS="`pwd`/pppd_cmd"
+
+cd modem_sim_esp32/esp-at
+
+python -m pip install -r requirements.txt
+
+python build.py reconfigure

common_components/modem_sim/install.sh

@@ -0,0 +1,64 @@
+#!/bin/bash
+set -e
+
+# Create directory "modem_sim_esp32", go inside it
+# Usage: ./install.sh [platform] [module]
+
+SCRIPT_DIR=$(pwd)
+mkdir -p modem_sim_esp32
+cd modem_sim_esp32
+
+if [ -z "$IDF_PATH" ]; then
+    echo "Error: IDF_PATH environment variable is not set"
+    exit 1
+fi
+
+# Default ESP_AT_VERSION uses this specific commit from master to support new chips and features
+ESP_AT_VERSION="aa9d7e0e9b741744f7bf5bec3bbf887cff033d5f"
+
+# Shallow clone of esp-at.git at $ESP_AT_VERSION
+if [ ! -d "esp-at" ]; then
+    # cannot shallow clone from a specific commit, so we init, shallow fetch, and checkout
+    mkdir -p esp-at && cd esp-at && git init && git remote add origin https://github.com/espressif/esp-at.git
+    git fetch --depth 1 origin $ESP_AT_VERSION && git checkout $ESP_AT_VERSION
+else
+    echo "esp-at directory already exists, skipping clone."
+    cd esp-at
+fi
+
+# Add esp-idf directory which is a symlink to the $IDF_PATH
+if [ ! -L "esp-idf" ]; then
+    ln -sf "$IDF_PATH" esp-idf
+else
+    echo "esp-idf symlink already exists, skipping."
+fi
+
+# Create "build" directory
+mkdir -p build
+
+# Default values for platform and module
+platform="PLATFORM_ESP32"
+module="WROOM-32"
+
+# Override defaults if parameters are provided
+if [ ! -z "$1" ]; then
+    platform="$1"
+fi
+if [ ! -z "$2" ]; then
+    module="$2"
+fi
+
+# Create file "build/module_info.json" with content
+cat > build/module_info.json << EOF
+{
+    "platform": "$platform",
+    "module": "$module",
+    "description": "4MB, Wi-Fi + BLE, OTA, TX:17 RX:16",
+    "silence": 0
+}
+EOF
+
+cp "$SCRIPT_DIR/sdkconfig.defaults" "module_config/module_esp32_default/sdkconfig.defaults"
+
+echo "Installation completed successfully!"
+echo "Created modem_sim_esp32 directory with esp-at repository and configuration"

common_components/modem_sim/pppd_cmd/CMakeLists.txt

@@ -0,0 +1,6 @@
+idf_component_register(
+    SRCS additional_commands.c
+    INCLUDE_DIRS include
+    REQUIRES at freertos nvs_flash)
+
+idf_component_set_property(${COMPONENT_NAME} WHOLE_ARCHIVE TRUE)

common_components/modem_sim/pppd_cmd/additional_commands.c

@@ -0,0 +1,411 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include "esp_at.h"
+#include "driver/gpio.h"
+#include "driver/uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/event_groups.h"
+#include "freertos/semphr.h"
+#include "freertos/queue.h"
+#include "esp_netif.h"
+#include "esp_netif_ppp.h"
+#include "esp_check.h"
+#include "esp_http_server.h"
+#include "esp_timer.h"
+
+static uint8_t at_test_cmd_test(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "test command: <AT%s=?> is executed\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_query_cmd_test(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "query command: <AT%s?> is executed\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_setup_cmd_test(uint8_t para_num)
+{
+    uint8_t index = 0;
+    printf("setup command: <AT%s=%d> is executed\r\n", esp_at_get_current_cmd_name(), para_num);
+
+    // get first parameter, and parse it into a digit
+    int32_t digit = 0;
+    if (esp_at_get_para_as_digit(index++, &digit) != ESP_AT_PARA_PARSE_RESULT_OK) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+    printf("digit: %d\r\n", digit);
+
+    // get second parameter, and parse it into a string
+    uint8_t *str = NULL;
+    if (esp_at_get_para_as_str(index++, &str) != ESP_AT_PARA_PARSE_RESULT_OK) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+    printf("string: %s\r\n", str);
+
+    // allocate a buffer and construct the data, then send the data to mcu via interface (uart/spi/sdio/socket)
+    uint8_t *buffer = (uint8_t *)malloc(512);
+    if (!buffer) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+    int len = snprintf((char *)buffer, 512, "setup command: <AT%s=%d,\"%s\"> is executed\r\n",
+                       esp_at_get_current_cmd_name(), digit, str);
+    esp_at_port_write_data(buffer, len);
+
+    // remember to free the buffer
+    free(buffer);
+
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+#define TAG "at_custom_cmd"
+static esp_netif_t *s_netif = NULL;
+static httpd_handle_t http_server = NULL;
+
+static void on_ppp_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
+{
+    esp_netif_t **netif = data;
+    if (base == NETIF_PPP_STATUS && event_id == NETIF_PPP_ERRORUSER) {
+        printf("Disconnected!");
+    }
+}
+
+static void on_ip_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
+{
+    ip_event_got_ip_t *event = (ip_event_got_ip_t *)data;
+    esp_netif_t *netif = event->esp_netif;
+    if (event_id == IP_EVENT_PPP_GOT_IP) {
+        printf("Got IPv4 event: Interface \"%s(%s)\" address: " IPSTR, esp_netif_get_desc(netif),
+               esp_netif_get_ifkey(netif), IP2STR(&event->ip_info.ip));
+        ESP_ERROR_CHECK(esp_netif_napt_enable(s_netif));
+
+    } else if (event_id == IP_EVENT_PPP_LOST_IP) {
+        ESP_LOGI(TAG, "Disconnected");
+    }
+}
+
+static SemaphoreHandle_t at_sync_sema = NULL;
+static void wait_data_callback(void)
+{
+    static uint8_t buffer[1500] = {0};
+    int len = esp_at_port_read_data(buffer, sizeof(buffer) - 1);
+
+    // Check for the escape sequence "+++" in the received data
+    const uint8_t escape_seq[] = "+++";
+    uint8_t *escape_ptr = memmem(buffer, len, escape_seq, 3);
+
+    if (escape_ptr != NULL) {
+        printf("Found +++ sequence, signal to the command processing thread\n");
+
+        int data_before_escape = escape_ptr - buffer;
+        if (data_before_escape > 0) {
+            esp_netif_receive(s_netif, buffer, data_before_escape, NULL);
+        }
+
+        if (at_sync_sema) {
+            xSemaphoreGive(at_sync_sema);
+        }
+        return;
+    }
+    esp_netif_receive(s_netif, buffer, len, NULL);
+}
+
+static esp_err_t transmit(void *h, void *buffer, size_t len)
+{
+    printf("transmit: %d bytes\n", len);
+    esp_at_port_write_data(buffer, len);
+    return ESP_OK;
+}
+
+static uint8_t at_exe_cmd_test(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "execute command: <AT%s> is executed\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+    printf("Command <AT%s> executed successfully\r\n", cmd_name);
+    if (!at_sync_sema) {
+        at_sync_sema = xSemaphoreCreateBinary();
+        assert(at_sync_sema != NULL);
+        esp_netif_driver_ifconfig_t driver_cfg = {
+            .handle = (void *)1,
+            .transmit = transmit,
+        };
+        const esp_netif_driver_ifconfig_t *ppp_driver_cfg = &driver_cfg;
+
+        esp_netif_inherent_config_t base_netif_cfg = ESP_NETIF_INHERENT_DEFAULT_PPP();
+        esp_netif_config_t netif_ppp_config = { .base = &base_netif_cfg,
+                                                .driver = ppp_driver_cfg,
+                                                .stack = ESP_NETIF_NETSTACK_DEFAULT_PPP
+                                              };
+
+        s_netif = esp_netif_new(&netif_ppp_config);
+        esp_netif_ppp_config_t netif_params;
+        ESP_ERROR_CHECK(esp_netif_ppp_get_params(s_netif, &netif_params));
+        netif_params.ppp_our_ip4_addr.addr = ESP_IP4TOADDR(192, 168, 11, 1);
+        netif_params.ppp_their_ip4_addr.addr = ESP_IP4TOADDR(192, 168, 11, 2);
+        netif_params.ppp_error_event_enabled = true;
+        ESP_ERROR_CHECK(esp_netif_ppp_set_params(s_netif, &netif_params));
+        if (esp_event_handler_register(IP_EVENT, ESP_EVENT_ANY_ID, on_ip_event, NULL) != ESP_OK) {
+            printf("Failed to register IP event handler");
+        }
+        if (esp_event_handler_register(NETIF_PPP_STATUS, ESP_EVENT_ANY_ID, on_ppp_event, NULL) !=  ESP_OK) {
+            printf("Failed to register NETIF_PPP_STATUS event handler");
+        }
+
+
+    }
+    esp_at_port_write_data((uint8_t *)"CONNECT\r\n", strlen("CONNECT\r\n"));
+
+    // set the callback function which will be called by AT port after receiving the input data
+    esp_at_port_enter_specific(wait_data_callback);
+    esp_netif_action_start(s_netif, 0, 0, 0);
+    esp_netif_action_connected(s_netif, 0, 0, 0);
+
+    while (xSemaphoreTake(at_sync_sema, pdMS_TO_TICKS(1000)) == pdFALSE) {
+        printf(".");
+    }
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_test_cereg(uint8_t *cmd_name)
+{
+    printf("%s: AT command <AT%s> is executed\r\n", __func__, cmd_name);
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_query_cereg(uint8_t *cmd_name)
+{
+    printf("%s: AT command <AT%s> is executed\r\n", __func__, cmd_name);
+    static uint8_t buffer[] = "+CEREG: 7,8\r\n";
+    esp_at_port_write_data(buffer, sizeof(buffer));
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_setup_cereg(uint8_t num)
+{
+    printf("%s: AT command <AT%d> is executed\r\n", __func__, num);
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_exe_cereg(uint8_t *cmd_name)
+{
+    printf("%s: AT command <AT%s> is executed\r\n", __func__, cmd_name);
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static esp_err_t hello_get_handler(httpd_req_t *req)
+{
+    const char* resp_str = "Hello from ESP-AT HTTP Server!";
+    httpd_resp_send(req, resp_str, HTTPD_RESP_USE_STRLEN);
+    return ESP_OK;
+}
+
+static esp_err_t root_get_handler(httpd_req_t *req)
+{
+    const char* resp_str = "ESP-AT HTTP Server is running";
+    httpd_resp_send(req, resp_str, HTTPD_RESP_USE_STRLEN);
+    return ESP_OK;
+}
+
+static esp_err_t test_get_handler(httpd_req_t *req)
+{
+    const char* resp_str = "{\"status\":\"success\",\"message\":\"Test endpoint working\",\"timestamp\":12345}";
+    httpd_resp_set_type(req, "application/json");
+    httpd_resp_send(req, resp_str, HTTPD_RESP_USE_STRLEN);
+    return ESP_OK;
+}
+
+static esp_err_t async_get_handler(httpd_req_t *req)
+{
+    printf("Starting async chunked response handler\r\n");
+
+    // Set content type for plain text response
+    httpd_resp_set_type(req, "text/plain");
+
+    // Static counter to track requests
+    static uint8_t req_count = 0;
+    req_count++;
+
+    // Send initial response with request count
+    char buffer[256];
+    snprintf(buffer, sizeof(buffer), "=== Async Response #%d ===\r\n", req_count);
+    httpd_resp_sendstr_chunk(req, buffer);
+
+    // Long message broken into chunks
+    const char* chunks[] = {
+        "This is a simulated slow server response.\r\n",
+        "Chunk 1: The ESP-AT HTTP server is demonstrating...\r\n",
+        "Chunk 2: ...asynchronous chunked transfer encoding...\r\n",
+        "Chunk 3: ...with artificial delays between chunks...\r\n",
+        "Chunk 4: ...to simulate real-world network conditions.\r\n",
+        "Chunk 5: Processing data... please wait...\r\n",
+        "Chunk 6: Still processing... almost done...\r\n",
+        "Chunk 7: Final chunk - transfer complete!\r\n",
+        "=== END OF RESPONSE ===\r\n"
+    };
+
+    int num_chunks = sizeof(chunks) / sizeof(chunks[0]);
+
+    // Send each chunk with delays
+    for (int i = 0; i < num_chunks; i++) {
+        // Add a delay to simulate slow processing
+        vTaskDelay(pdMS_TO_TICKS(1500)); // 1.5 second delay between chunks
+
+        // Add chunk number and timestamp
+        snprintf(buffer, sizeof(buffer), "[%d/%d] [%d ms] %s",
+                 i + 1, num_chunks, (int)(esp_timer_get_time() / 1000), chunks[i]);
+
+        printf("Sending chunk %d: %s", i + 1, chunks[i]);
+        httpd_resp_sendstr_chunk(req, buffer);
+    }
+
+    // Add final summary
+    vTaskDelay(pdMS_TO_TICKS(500));
+    snprintf(buffer, sizeof(buffer), "\r\nTransfer completed in %d chunks with delays.\r\n", num_chunks);
+    httpd_resp_sendstr_chunk(req, buffer);
+
+    // Send NULL to signal end of chunked transfer
+    httpd_resp_sendstr_chunk(req, NULL);
+
+    printf("Async chunked response completed\r\n");
+    return ESP_OK;
+}
+
+static const httpd_uri_t hello = {
+    .uri       = "/hello",
+    .method    = HTTP_GET,
+    .handler   = hello_get_handler,
+    .user_ctx  = NULL
+};
+
+static const httpd_uri_t root = {
+    .uri       = "/",
+    .method    = HTTP_GET,
+    .handler   = root_get_handler,
+    .user_ctx  = NULL
+};
+
+static const httpd_uri_t test = {
+    .uri       = "/test",
+    .method    = HTTP_GET,
+    .handler   = test_get_handler,
+    .user_ctx  = NULL
+};
+
+static const httpd_uri_t async_uri = {
+    .uri       = "/async",
+    .method    = HTTP_GET,
+    .handler   = async_get_handler,
+    .user_ctx  = NULL
+};
+
+static esp_err_t start_http_server(void)
+{
+    if (http_server != NULL) {
+        printf("HTTP server already running\r\n");
+        return ESP_OK;
+    }
+
+    httpd_config_t config = HTTPD_DEFAULT_CONFIG();
+    config.server_port = 8080;
+    config.lru_purge_enable = true;
+
+    printf("Starting HTTP server on port: %d\r\n", config.server_port);
+    if (httpd_start(&http_server, &config) == ESP_OK) {
+        printf("Registering URI handlers\r\n");
+        httpd_register_uri_handler(http_server, &hello);
+        httpd_register_uri_handler(http_server, &root);
+        httpd_register_uri_handler(http_server, &test);
+        httpd_register_uri_handler(http_server, &async_uri);
+        return ESP_OK;
+    }
+
+    printf("Error starting HTTP server!\r\n");
+    return ESP_FAIL;
+}
+
+static esp_err_t stop_http_server(void)
+{
+    if (http_server != NULL) {
+        httpd_stop(http_server);
+        http_server = NULL;
+        printf("HTTP server stopped\r\n");
+        return ESP_OK;
+    }
+    return ESP_OK;
+}
+
+/* HTTP Server AT Commands */
+static uint8_t at_test_httpd(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "AT%s=<0/1> - Start/Stop HTTP server\r\n", cmd_name);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_query_httpd(uint8_t *cmd_name)
+{
+    uint8_t buffer[64] = {0};
+    snprintf((char *)buffer, 64, "+HTTPD:%d\r\n", http_server != NULL ? 1 : 0);
+    esp_at_port_write_data(buffer, strlen((char *)buffer));
+    return ESP_AT_RESULT_CODE_OK;
+}
+
+static uint8_t at_setup_httpd(uint8_t para_num)
+{
+    int32_t action = 0;
+    if (esp_at_get_para_as_digit(0, &action) != ESP_AT_PARA_PARSE_RESULT_OK) {
+        return ESP_AT_RESULT_CODE_ERROR;
+    }
+
+    if (action == 1) {
+        if (start_http_server() == ESP_OK) {
+            printf("HTTP server started successfully\r\n");
+            return ESP_AT_RESULT_CODE_OK;
+        }
+    } else if (action == 0) {
+        if (stop_http_server() == ESP_OK) {
+            return ESP_AT_RESULT_CODE_OK;
+        }
+    }
+
+    return ESP_AT_RESULT_CODE_ERROR;
+}
+
+static uint8_t at_exe_httpd(uint8_t *cmd_name)
+{
+    // Default action: start server
+    if (start_http_server() == ESP_OK) {
+        printf("HTTP server started via execute command\r\n");
+        return ESP_AT_RESULT_CODE_OK;
+    }
+    return ESP_AT_RESULT_CODE_ERROR;
+}
+
+
+static const esp_at_cmd_struct at_custom_cmd[] = {
+    {"+PPPD", at_test_cmd_test, at_query_cmd_test, at_setup_cmd_test, at_exe_cmd_test},
+    {"+CEREG", at_test_cereg, at_query_cereg, at_setup_cereg, at_exe_cereg},
+    {"+HTTPD", at_test_httpd, at_query_httpd, at_setup_httpd, at_exe_httpd},
+};
+
+bool esp_at_custom_cmd_register(void)
+{
+    return esp_at_custom_cmd_array_regist(at_custom_cmd, sizeof(at_custom_cmd) / sizeof(esp_at_cmd_struct));
+}
+
+ESP_AT_CMD_SET_INIT_FN(esp_at_custom_cmd_register, 1);

common_components/modem_sim/pppd_cmd/include/at_custom_cmd.h

@@ -0,0 +1,12 @@
+/*
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+#include "esp_at_core.h"
+#include "esp_at.h"
+
+/**
+ * @brief You can include more header files here for your own AT commands.
+ */

common_components/modem_sim/sdkconfig.defaults

@@ -0,0 +1,77 @@
+# This file was generated using idf.py save-defconfig. It can be edited manually.
+# Espressif IoT Development Framework (ESP-IDF) 5.4.1 Project Minimal Configuration
+#
+CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE=y
+CONFIG_APP_PROJECT_VER_FROM_CONFIG=y
+CONFIG_APP_PROJECT_VER="v4.1.0.0-dev"
+CONFIG_ESPTOOLPY_FLASHSIZE_4MB=y
+CONFIG_PARTITION_TABLE_CUSTOM=y
+CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="module_config/module_esp32_default/partitions_at.csv"
+CONFIG_PARTITION_TABLE_MD5=n
+CONFIG_AT_CUSTOMIZED_PARTITION_TABLE_FILE="module_config/module_esp32_default/at_customize.csv"
+CONFIG_BT_ENABLED=y
+CONFIG_BT_BTU_TASK_STACK_SIZE=5120
+CONFIG_BT_BLE_BLUFI_ENABLE=y
+CONFIG_BT_STACK_NO_LOG=y
+CONFIG_BT_BLE_DYNAMIC_ENV_MEMORY=y
+CONFIG_BTDM_CTRL_MODE_BTDM=y
+CONFIG_BTDM_CTRL_LPCLK_SEL_EXT_32K_XTAL=y
+CONFIG_BTDM_SCAN_DUPL_CACHE_SIZE=200
+CONFIG_ESP_TLS_PSK_VERIFICATION=y
+CONFIG_ESP_TLS_INSECURE=y
+CONFIG_ESP_TLS_SKIP_SERVER_CERT_VERIFY=y
+CONFIG_ESP_ERR_TO_NAME_LOOKUP=n
+CONFIG_GPIO_ESP32_SUPPORT_SWITCH_SLP_PULL=y
+CONFIG_ETH_DMA_RX_BUFFER_NUM=3
+CONFIG_ETH_DMA_TX_BUFFER_NUM=3
+CONFIG_HTTPD_MAX_REQ_HDR_LEN=1024
+CONFIG_HTTPD_MAX_URI_LEN=1024
+CONFIG_ESP_HTTPS_OTA_ALLOW_HTTP=y
+CONFIG_RTC_CLK_SRC_EXT_CRYS=y
+CONFIG_RTC_EXT_CRYST_ADDIT_CURRENT=y
+CONFIG_RTC_CLK_CAL_CYCLES=1024
+CONFIG_PM_ENABLE=y
+CONFIG_PM_SLP_DISABLE_GPIO=y
+CONFIG_ESP_DEFAULT_CPU_FREQ_MHZ_80=y
+CONFIG_ESP_TASK_WDT_PANIC=y
+CONFIG_ESP_TASK_WDT_TIMEOUT_S=60
+CONFIG_ESP_DEBUG_OCDAWARE=n
+CONFIG_ESP_WIFI_IRAM_OPT=n
+CONFIG_ESP_WIFI_RX_IRAM_OPT=n
+CONFIG_ESP_WIFI_SLP_IRAM_OPT=y
+CONFIG_ESP_WIFI_SLP_BEACON_LOST_OPT=y
+CONFIG_ESP_WIFI_ESPNOW_MAX_ENCRYPT_NUM=0
+CONFIG_FATFS_LFN_HEAP=y
+CONFIG_FREERTOS_UNICORE=y
+CONFIG_FREERTOS_HZ=1000
+CONFIG_FREERTOS_USE_TICKLESS_IDLE=y
+CONFIG_FREERTOS_CHECK_MUTEX_GIVEN_BY_OWNER=n
+CONFIG_FREERTOS_PLACE_FUNCTIONS_INTO_FLASH=y
+CONFIG_HEAP_PLACE_FUNCTION_INTO_FLASH=y
+CONFIG_LOG_DEFAULT_LEVEL_ERROR=y
+CONFIG_LWIP_MAX_SOCKETS=16
+CONFIG_LWIP_SO_LINGER=y
+CONFIG_LWIP_SO_RCVBUF=y
+CONFIG_LWIP_IP4_REASSEMBLY=y
+CONFIG_LWIP_IP6_REASSEMBLY=y
+CONFIG_LWIP_IPV6_AUTOCONFIG=y
+CONFIG_LWIP_TCP_MAXRTX=6
+CONFIG_LWIP_TCP_SYNMAXRTX=3
+CONFIG_LWIP_PPP_SUPPORT=y
+CONFIG_LWIP_PPP_SERVER_SUPPORT=y
+CONFIG_LWIP_SNTP_MAX_SERVERS=3
+CONFIG_LWIP_SNTP_STARTUP_DELAY=n
+CONFIG_MBEDTLS_DYNAMIC_BUFFER=y
+CONFIG_MBEDTLS_DYNAMIC_FREE_CONFIG_DATA=y
+CONFIG_MBEDTLS_SSL_KEEP_PEER_CERTIFICATE=n
+CONFIG_MBEDTLS_HAVE_TIME_DATE=y
+CONFIG_MBEDTLS_DHM_C=y
+CONFIG_NEWLIB_NANO_FORMAT=y
+CONFIG_VFS_SUPPORT_TERMIOS=n
+CONFIG_WL_SECTOR_SIZE_512=y
+CONFIG_AT_PROCESS_TASK_STACK_SIZE=6144
+CONFIG_AT_MQTT_COMMAND_SUPPORT=y
+CONFIG_AT_HTTP_COMMAND_SUPPORT=y
+CONFIG_AT_BLE_COMMAND_SUPPORT=n
+CONFIG_AT_BLE_HID_COMMAND_SUPPORT=n
+CONFIG_AT_BLUFI_COMMAND_SUPPORT=n

components/eppp_link/.cz.yaml

@@ -3,6 +3,6 @@ commitizen:
   bump_message: 'bump(eppp): $current_version -> $new_version'
   pre_bump_hooks: python ../../ci/changelog.py eppp_link
   tag_format: eppp-v$version
-  version: 0.3.0
+  version: 1.0.0
   version_files:
   - idf_component.yml

components/eppp_link/CHANGELOG.md

@@ -1,5 +1,17 @@
 # Changelog
 
+## [1.0.0](https://github.com/espressif/esp-protocols/commits/eppp-v1.0.0)
+
+### Features
+
+- Add support for custom channels ([4ee9360f](https://github.com/espressif/esp-protocols/commit/4ee9360f))
+
+## [0.3.1](https://github.com/espressif/esp-protocols/commits/eppp-v0.3.1)
+
+### Bug Fixes
+
+- Fix NETIF_PPP_STATUS link issue if PPP disabled in lwip ([077ea0bb](https://github.com/espressif/esp-protocols/commit/077ea0bb))
+
 ## [0.3.0](https://github.com/espressif/esp-protocols/commits/eppp-v0.3.0)
 
 ### Features

components/eppp_link/Kconfig

@@ -93,4 +93,21 @@ menu "eppp_link"
         default "06:00:00:00:00:02"
         depends on EPPP_LINK_DEVICE_ETH
 
+    config EPPP_LINK_CHANNELS_SUPPORT
+        bool "Enable channel support (multiple logical channels)"
+        default n
+        depends on !EPPP_LINK_DEVICE_ETH
+        help
+            Enable support for multiple logical channels in the EPPP link layer.
+            When enabled, you can configure the number of channels used for communication.
+
+    config EPPP_LINK_NR_OF_CHANNELS
+        int "Number of logical channels"
+        depends on EPPP_LINK_CHANNELS_SUPPORT && !EPPP_LINK_DEVICE_ETH
+        range 1 8
+        default 2
+        help
+            Set the number of logical channels for EPPP link communication.
+            Each channel can be used for independent data streams.
+
 endmenu

components/eppp_link/README.md

@@ -1,7 +1,7 @@
 # ESP PPP Link component (eppp_link)
 
 The component provides a general purpose connectivity engine between two microcontrollers, one acting as PPP server, the other one as PPP client.
-This component could be used for extending network using physical serial connection. Applications could vary from providing PRC engine for multiprocessor solutions to serial connection to POSIX machine. This uses a standard PPP protocol (if enabled) to negotiate IP addresses and networking, so standard PPP toolset could be used, e.g. a `pppd` service on linux. Typical application is a WiFi connectivity provider for chips that do not have WiFi.
+This component could be used for extending network using physical serial connection. Applications could vary from providing RPC engine for multiprocessor solutions to serial connection to POSIX machine. This uses a standard PPP protocol (if enabled) to negotiate IP addresses and networking, so standard PPP toolset could be used, e.g. a `pppd` service on linux. Typical application is a WiFi connectivity provider for chips that do not have WiFi.
 Uses simplified TUN network interface by default to enable faster data transfer on non-UART transports.
 
 ## Typical application
@@ -21,6 +21,27 @@ brings in the WiFi connectivity from the communication coprocessor.
          +----------------+                               +----------------+
 ```
 
+## Features
+
+### Network Interface Modes
+
+Standard PPP Mode (where PPP protocols is preferred) or simple tunnel using TUN Mode.
+
+### Transport layer
+
+UART, SPI, SDIO, Ethernet
+
+### Support for logical channels
+
+Allows channeling custom data (e.g. 802.11 frames)
+
+## (Other) usecases
+
+Besides the communication coprocessor example mentioned above, this component could be used to:
+* Bring Wi-Fi connectivity to a computer using ESP32 chip.
+* Connect your microcontroller to the internet via a pppd server (running on a raspberry)
+* Bridging two networks with two microcontrollers
+
 ## Configuration
 
 ### Choose the transport layer
@@ -39,6 +60,14 @@ Use `idf.py menuconfig` to select the transport layer:
 
 Use PPP netif for UART; Keep the default (TUN) for others
 
+### Channel support (multiple logical channels)
+
+* `CONFIG_EPPP_LINK_CHANNELS_SUPPORT` -- Enable support for multiple logical channels (default: disabled)
+* `CONFIG_EPPP_LINK_NR_OF_CHANNELS` -- Number of logical channels (default: 2, range: 1-8, only visible if channel support is enabled)
+
+When channel support is enabled, the EPPP link can multiplex multiple logical data streams over the same transport. The number of channels is configurable. Channel support is not available for Ethernet transport.
+
+To use channels in your application, use the `eppp_add_channels()` API and provide your own channel transmit/receive callbacks. These APIs and related types are only available when channel support is enabled in Kconfig.
 
 ## API
 
@@ -57,6 +86,9 @@ Use PPP netif for UART; Keep the default (TUN) for others
 * `eppp_netif_start()` -- Starts the network, could be called after startup or whenever a connection is lost
 * `eppp_netif_stop()` --  Stops the network
 * `eppp_perform()` -- Perform one iteration of the PPP task (need to be called regularly in task-less configuration)
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+* `eppp_add_channels()` -- Register channel transmit/receive callbacks (only available if channel support is enabled)
+#endif
 
 ## Throughput
 

components/eppp_link/detailed_description.md

@@ -0,0 +1,370 @@
+# ESP PPP Link Component (eppp_link) - Detailed Documentation
+
+## Overview
+
+The ESP PPP Link component provides a versatile communication bridge between two ESP32 microcontrollers, enabling network connectivity over various physical transport layers. One device acts as a server (typically providing connectivity), while the other acts as a client (consuming connectivity).
+
+## Network Interface Modes
+
+### PPP Mode vs TUN Mode
+
+The component supports two distinct network interface modes:
+
+#### PPP Mode (`CONFIG_EPPP_LINK_USES_PPP=y`)
+- **Standard PPP Protocol**: Uses the Point-to-Point Protocol (RFC 1661) with full LCP negotiation
+- **Compatibility**: Compatible with standard PPP implementations like Linux `pppd`
+- **Features**:
+  - Automatic IP address negotiation
+  - Link Control Protocol (LCP) for connection establishment
+  - Authentication support (if configured)
+  - Standard PPP framing with escape sequences
+- **Use Case**: When interfacing with standard PPP-capable systems or when full PPP compatibility is required
+- **Transport Limitation**: Primarily designed for UART transport due to PPP's serial nature
+
+#### TUN Mode (`CONFIG_EPPP_LINK_USES_PPP=n`, default)
+- **Simplified Packet Interface**: Uses a custom packet-based protocol without PPP negotiation
+- **Performance**: Faster data transfer due to reduced protocol overhead
+- **Features**:
+  - Direct IP packet transmission
+  - Custom framing for packet boundaries
+  - No negotiation overhead
+  - Static IP address configuration
+- **Use Case**: Default mode for ESP-to-ESP communication, optimal for non-UART transports
+- **Transport Support**: Works efficiently with all transport types (UART, SPI, SDIO, Ethernet)
+
+**Mode Selection**: Configure via `idf.py menuconfig` → `Component config` → `eppp_link` → `Use PPP network interface`
+
+## Transport Layer Options
+
+### UART Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_UART=y`
+- **Features**:
+  - Simple serial communication
+  - Configurable baud rate (up to 3Mbps tested)
+  - Hardware flow control support
+  - Custom framing for packet boundaries in TUN mode
+- **Performance**: ~2 Mbps (TCP/UDP) @ 3 Mbaud
+- **Use Case**: Basic connectivity, long-distance communication, debugging
+- **Pins**: TX, RX configurable
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_UART;
+config.uart.tx_io = 25;
+config.uart.rx_io = 26;
+config.uart.baud = 921600;
+```
+
+### SPI Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_SPI=y`
+- **Features**:
+  - Master/slave configuration
+  - GPIO interrupt signaling for flow control
+  - Configurable clock frequency
+  - Full-duplex communication
+  - Packet queue for transmission
+- **Performance**: ~5 Mbps (TCP), ~8 Mbps (UDP) @ 16MHz
+- **Use Case**: High-speed local communication, PCB-level connections
+- **Pins**: MOSI, MISO, SCLK, CS, interrupt GPIO
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_SPI;
+config.spi.is_master = true;
+config.spi.freq = 16000000;
+config.spi.mosi = 11;
+config.spi.miso = 13;
+config.spi.sclk = 12;
+config.spi.cs = 10;
+config.spi.intr = 2;
+```
+
+### SDIO Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_SDIO=y`
+- **Features**:
+  - Host/slave configuration
+  - High-speed data transfer
+  - 1-bit or 4-bit bus width
+  - Hardware flow control
+- **Performance**: ~9 Mbps (TCP), ~11 Mbps (UDP)
+- **Use Case**: Highest throughput applications, module-to-module communication
+- **Pins**: CLK, CMD, D0-D3 (configurable width)
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_SDIO;
+config.sdio.is_host = true;
+config.sdio.width = 4;
+config.sdio.clk = 18;
+config.sdio.cmd = 19;
+config.sdio.d0 = 14;
+// ... additional data pins
+```
+
+### Ethernet Transport
+- **Configuration**: `CONFIG_EPPP_LINK_DEVICE_ETH=y`
+- **Features**:
+  - Direct MAC-to-MAC communication
+  - Can work with or without PHY chips
+  - Standard Ethernet framing
+  - Automatic task management (no `eppp_perform()` needed)
+- **Performance**: ~5 Mbps (TCP), ~8 Mbps (UDP) with internal EMAC
+- **Use Case**: Board-to-board communication, integration with existing Ethernet infrastructure
+- **Pins**: MDC, MDIO, plus PHY-specific pins
+
+```c
+eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+config.transport = EPPP_TRANSPORT_ETHERNET;
+config.ethernet.mdc_io = 23;
+config.ethernet.mdio_io = 18;
+config.ethernet.phy_addr = 1;
+config.ethernet.rst_io = 5;
+```
+
+## Channel Support (Multiple Logical Channels)
+
+### Overview
+Channel support allows multiplexing multiple independent data streams over a single transport connection. This enables applications to separate different types of data (e.g., network traffic, control commands, sensor data) into distinct logical channels.
+
+### Configuration
+- **Enable**: `CONFIG_EPPP_LINK_CHANNELS_SUPPORT=y`
+- **Count**: `CONFIG_EPPP_LINK_NR_OF_CHANNELS` (1-8 channels, default 2)
+- **Limitation**: Not available for Ethernet transport
+
+### Channel Usage
+```c
+// Channel callback function type
+typedef esp_err_t (*eppp_channel_fn_t)(esp_netif_t *netif, int nr, void *buffer, size_t len);
+
+// Register channel callbacks
+esp_err_t eppp_add_channels(esp_netif_t *netif,
+                           eppp_channel_fn_t *tx,     // Transmit function pointer (output)
+                           const eppp_channel_fn_t rx, // Receive callback (input)
+                           void* context);             // User context
+
+// Get user context
+void* eppp_get_context(esp_netif_t *netif);
+```
+
+### Channel Example
+```c
+// Channel 0: Default network traffic (handled automatically)
+// Channel 1: Control/chat messages
+// Channel 2: WiFi data forwarding
+
+static esp_err_t channel_receive(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    switch(channel) {
+        case 1: // Control channel
+            process_control_message(buffer, len);
+            break;
+        case 2: // WiFi channel
+            forward_to_wifi(buffer, len);
+            break;
+        default:
+            ESP_LOGE(TAG, "Unknown channel %d", channel);
+            return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+// Register channels
+eppp_channel_fn_t tx_func;
+eppp_add_channels(netif, &tx_func, channel_receive, user_context);
+
+// Transmit on specific channel
+tx_func(netif, 1, "Hello", 5);  // Send to channel 1
+```
+
+## API Reference
+
+### Simple API (Recommended for most use cases)
+
+#### Client Side
+```c
+esp_netif_t *eppp_connect(eppp_config_t *config);
+```
+- **Purpose**: Simplified client connection
+- **Behavior**: Blocks until connection is established
+- **Returns**: Configured network interface or NULL on failure
+- **Use Case**: Simple applications that don't need fine-grained control
+
+#### Server Side
+```c
+esp_netif_t *eppp_listen(eppp_config_t *config);
+```
+- **Purpose**: Simplified server listening
+- **Behavior**: Blocks until client connects
+- **Returns**: Configured network interface or NULL on failure
+- **Use Case**: Simple applications that don't need fine-grained control
+
+#### Connection Management
+```c
+void eppp_close(esp_netif_t *netif);
+```
+- **Purpose**: Close connection and cleanup resources
+- **Behavior**: Stops tasks, closes transport, destroys network interface
+
+### Advanced API (Manual Control)
+
+#### Initialization
+```c
+esp_netif_t *eppp_init(eppp_type_t role, eppp_config_t *config);
+```
+- **Purpose**: Initialize endpoint without starting communication
+- **Parameters**:
+  - `role`: `EPPP_SERVER` or `EPPP_CLIENT`
+  - `config`: Transport and network configuration
+- **Returns**: Network interface handle
+- **Use Case**: Applications needing manual control over connection lifecycle
+
+#### Connection Control
+```c
+esp_err_t eppp_netif_start(esp_netif_t *netif);
+esp_err_t eppp_netif_stop(esp_netif_t *netif, int stop_timeout_ms);
+```
+- **Purpose**: Manual network interface start/stop
+- **Use Case**: Dynamic connection management, error recovery
+
+#### Task Management
+```c
+esp_err_t eppp_perform(esp_netif_t *netif);
+```
+- **Purpose**: Single iteration of communication task
+- **Returns**:
+  - `ESP_OK`: Continue operation
+  - `ESP_FAIL`: Operation failed but should continue
+  - `ESP_ERR_TIMEOUT`: Stop operation requested
+- **Use Case**: Task-less operation, integration with custom task schedulers
+- **Note**: Not needed for Ethernet transport (has its own task)
+
+#### Resource Management
+```c
+void eppp_deinit(esp_netif_t *netif);
+```
+- **Purpose**: Clean up resources without stopping tasks
+- **Use Case**: Manual resource management
+
+## Configuration Examples
+
+### Basic Client-Server Setup
+
+**Client (Host) Configuration:**
+```c
+void app_main(void)
+{
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+    config.transport = EPPP_TRANSPORT_UART;
+    config.uart.tx_io = 25;
+    config.uart.rx_io = 26;
+    config.uart.baud = 921600;
+
+    esp_netif_t *netif = eppp_connect(&config);
+    if (netif == NULL) {
+        ESP_LOGE(TAG, "Failed to connect");
+        return;
+    }
+
+    ESP_LOGI(TAG, "Connected successfully");
+    // Use network interface for communication
+}
+```
+
+**Server (Slave) Configuration:**
+```c
+void app_main(void)
+{
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    // Initialize WiFi or other network interface
+    init_wifi();
+
+    eppp_config_t config = EPPP_DEFAULT_SERVER_CONFIG();
+    config.transport = EPPP_TRANSPORT_UART;
+    config.uart.tx_io = 26;  // Crossed with client
+    config.uart.rx_io = 25;  // Crossed with client
+    config.uart.baud = 921600;
+
+    esp_netif_t *netif = eppp_listen(&config);
+    if (netif == NULL) {
+        ESP_LOGE(TAG, "Failed to setup server");
+        return;
+    }
+
+    // Enable NAT to share WiFi connection
+    ESP_ERROR_CHECK(esp_netif_napt_enable(netif));
+    ESP_LOGI(TAG, "Server ready");
+}
+```
+
+### Advanced Manual Control
+```c
+void app_main(void)
+{
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+    config.task.run_task = false;  // Disable automatic task
+
+    esp_netif_t *netif = eppp_init(EPPP_CLIENT, &config);
+    if (netif == NULL) {
+        ESP_LOGE(TAG, "Failed to initialize");
+        return;
+    }
+
+    // Start network interface
+    ESP_ERROR_CHECK(eppp_netif_start(netif));
+
+    // Custom task loop
+    while (true) {
+        esp_err_t ret = eppp_perform(netif);
+        if (ret == ESP_ERR_TIMEOUT) {
+            ESP_LOGI(TAG, "Operation stopped");
+            break;
+        } else if (ret != ESP_OK) {
+            ESP_LOGE(TAG, "Operation failed: %s", esp_err_to_name(ret));
+        }
+
+        // Add custom processing here
+        vTaskDelay(pdMS_TO_TICKS(1));
+    }
+
+    eppp_deinit(netif);
+}
+```
+
+### Multi-Channel Configuration
+```c
+typedef struct {
+    eppp_channel_fn_t tx_func;
+    esp_netif_t *netif;
+} channel_context_t;
+
+static esp_err_t channel_rx(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    ESP_LOGI(TAG, "Channel %d received %d bytes", channel, len);
+    // Process channel data based on channel number
+    return ESP_OK;
+}
+
+void setup_channels(void)
+{
+    eppp_config_t config = EPPP_DEFAULT_CLIENT_CONFIG();
+    esp_netif_t *netif = eppp_connect(&config);
+
+    channel_context_t *ctx = calloc(1, sizeof(channel_context_t));
+    ctx->netif = netif;
+
+    // Register channel callbacks
+    ESP_ERROR_CHECK(eppp_add_channels(netif, &ctx->tx_func, channel_rx, ctx));
+
+    // Send data on channel 1
+    const char *msg = "Hello on channel 1";
+    ctx->tx_func(netif, 1, (void*)msg, strlen(msg));
+}
+```

components/eppp_link/eppp_link.c

@@ -163,6 +163,7 @@ static int get_netif_num(esp_netif_t *netif)
     return  netif_cnt;
 }
 
+#ifdef CONFIG_EPPP_LINK_USES_PPP
 static void on_ppp_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
 {
     esp_netif_t **netif = data;
@@ -172,6 +173,7 @@ static void on_ppp_event(void *arg, esp_event_base_t base, int32_t event_id, voi
         h->netif_stop = true;
     }
 }
+#endif // CONFIG_EPPP_LINK_USES_PPP
 
 static void on_ip_event(void *arg, esp_event_base_t base, int32_t event_id, void *data)
 {
@@ -222,7 +224,9 @@ static void remove_handlers(void)
         vEventGroupDelete(s_event_group);
         s_event_group = NULL;
         esp_event_handler_unregister(IP_EVENT, ESP_EVENT_ANY_ID, on_ip_event);
+#ifdef CONFIG_EPPP_LINK_USES_PPP
         esp_event_handler_unregister(NETIF_PPP_STATUS, ESP_EVENT_ANY_ID, on_ppp_event);
+#endif
     }
 }
 
@@ -296,11 +300,13 @@ esp_netif_t *eppp_open(eppp_type_t role, eppp_config_t *config, int connect_time
             remove_handlers();
             return NULL;
         }
+#ifdef CONFIG_EPPP_LINK_USES_PPP
         if (esp_event_handler_register(NETIF_PPP_STATUS, ESP_EVENT_ANY_ID, on_ppp_event, NULL) !=  ESP_OK) {
             ESP_LOGE(TAG, "Failed to register PPP status handler");
             remove_handlers();
             return NULL;
         }
+#endif // CONFIG_EPPP_LINK_USES_PPP
     }
     esp_netif_t *netif = eppp_init(role, config);
     if (!netif) {
@@ -361,3 +367,24 @@ void eppp_close(esp_netif_t *netif)
     eppp_deinit(netif);
     remove_handlers();
 }
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+esp_err_t eppp_add_channels(esp_netif_t *netif, eppp_channel_fn_t *tx, const eppp_channel_fn_t rx, void* context)
+{
+    ESP_RETURN_ON_FALSE(netif != NULL && tx != NULL && rx != NULL, ESP_ERR_INVALID_ARG, TAG, "Invalid arguments");
+    struct eppp_handle *h = esp_netif_get_io_driver(netif);
+    ESP_RETURN_ON_FALSE(h != NULL && h->channel_tx != NULL, ESP_ERR_INVALID_STATE, TAG, "Transport not initialized");
+    *tx = h->channel_tx;
+    h->channel_rx = rx;
+    h->context = context;
+    return ESP_OK;
+}
+
+void* eppp_get_context(esp_netif_t *netif)
+{
+    ESP_RETURN_ON_FALSE(netif != NULL, NULL, TAG, "Invalid netif");
+    struct eppp_handle *h = esp_netif_get_io_driver(netif);
+    ESP_RETURN_ON_FALSE(h != NULL, NULL, TAG, "EPPP Not initialized");
+    return h->context;
+}
+#endif

components/eppp_link/eppp_sdio.c

@@ -13,6 +13,7 @@
 #include "eppp_link.h"
 #include "eppp_transport.h"
 #include "eppp_transport_sdio.h"
+#include "eppp_sdio.h"
 
 #define TAG "eppp_sdio"
 
@@ -67,6 +68,9 @@ eppp_transport_handle_t eppp_sdio_init(struct eppp_config_sdio_s *config)
     ESP_RETURN_ON_FALSE(config, NULL, TAG, "Config cannot be null");
     struct eppp_sdio *h = calloc(1, sizeof(struct eppp_sdio));
     ESP_RETURN_ON_FALSE(h, NULL, TAG, "Failed to allocate eppp_handle");
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    h->parent.channel_tx = eppp_sdio_transmit_channel;
+#endif
     h->parent.base.post_attach = post_attach;
     h->is_host = config->is_host;
     esp_err_t (*init_fn)(struct eppp_config_sdio_s * eppp_config) = h->is_host ? eppp_sdio_host_init : eppp_sdio_slave_init;

components/eppp_link/eppp_sdio.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -8,8 +8,10 @@
 #define MAX_SDIO_PAYLOAD 1500
 #define SDIO_ALIGN(size) (((size) + 3U) & ~(3U))
 #define SDIO_PAYLOAD SDIO_ALIGN(MAX_SDIO_PAYLOAD)
+#define SDIO_PACKET_SIZE SDIO_ALIGN(MAX_SDIO_PAYLOAD + 4)
 #define PPP_SOF 0x7E
 
+
 // Interrupts and registers
 #define SLAVE_INTR      0
 #define SLAVE_REG_REQ   0
@@ -17,3 +19,11 @@
 // Requests from host to slave
 #define REQ_RESET 1
 #define REQ_INIT  2
+
+struct header {
+    uint8_t magic;
+    uint8_t channel;
+    uint16_t size;
+} __attribute__((packed));
+
+esp_err_t eppp_sdio_transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len);

components/eppp_link/eppp_sdio_host.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -15,6 +15,7 @@
 #include "sdmmc_cmd.h"
 #include "esp_check.h"
 #include "eppp_link.h"
+#include "eppp_transport.h"
 
 #if CONFIG_EPPP_LINK_DEVICE_SDIO_HOST
 
@@ -28,22 +29,23 @@ static SemaphoreHandle_t s_essl_mutex = NULL;
 static essl_handle_t s_essl = NULL;
 static sdmmc_card_t *s_card = NULL;
 
-static DRAM_DMA_ALIGNED_ATTR uint8_t send_buffer[SDIO_PAYLOAD];
-static DMA_ATTR uint8_t rcv_buffer[SDIO_PAYLOAD];
+static DRAM_DMA_ALIGNED_ATTR uint8_t send_buffer[SDIO_PACKET_SIZE];
+static DMA_ATTR uint8_t rcv_buffer[SDIO_PACKET_SIZE];
 
-esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len)
+static esp_err_t eppp_sdio_host_tx_generic(int channel, void *buffer, size_t len)
 {
     if (s_essl == NULL || s_essl_mutex == NULL) {
         // silently skip the Tx if the SDIO not fully initialized
         return ESP_OK;
     }
 
-    memcpy(send_buffer, buffer, len);
-    size_t send_len = SDIO_ALIGN(len);
-    if (send_len > len) {
-        // pad with SOF's
-        memset(&send_buffer[len], PPP_SOF, send_len - len);
-    }
+
+    struct header *head = (void *)send_buffer;
+    head->magic = PPP_SOF;
+    head->channel = channel;
+    head->size = len;
+    memcpy(send_buffer + sizeof(struct header), buffer, len);
+    size_t send_len = SDIO_ALIGN(len + sizeof(struct header));
     xSemaphoreTake(s_essl_mutex, portMAX_DELAY);
     esp_err_t ret = essl_send_packet(s_essl, send_buffer, send_len, PACKET_TIMEOUT_MS);
     if (ret != ESP_OK) {
@@ -56,6 +58,19 @@ esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len)
     return ret;
 }
 
+esp_err_t eppp_sdio_host_tx(void *h, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+esp_err_t eppp_sdio_transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(channel, buffer, len);
+}
+#endif
+
+
 static esp_err_t request_slave_reset(void)
 {
     esp_err_t ret = ESP_OK;
@@ -145,15 +160,37 @@ esp_err_t eppp_sdio_host_rx(esp_netif_t *netif)
     if (intr & ESSL_SDIO_DEF_ESP32.new_packet_intr_mask) {
         esp_err_t ret;
         do {
-            size_t size_read = SDIO_PAYLOAD;
-            ret = essl_get_packet(s_essl, rcv_buffer, SDIO_PAYLOAD, &size_read, PACKET_TIMEOUT_MS);
+            size_t size_read = SDIO_PACKET_SIZE;
+            ret = essl_get_packet(s_essl, rcv_buffer, SDIO_PACKET_SIZE, &size_read, PACKET_TIMEOUT_MS);
             if (ret == ESP_ERR_NOT_FOUND) {
                 ESP_LOGE(TAG, "interrupt but no data can be read");
                 break;
             } else if (ret == ESP_OK) {
                 ESP_LOGD(TAG, "receive data, size: %d", size_read);
+                struct header *head = (void *)rcv_buffer;
+                if (head->magic != PPP_SOF) {
+                    ESP_LOGE(TAG, "invalid magic %x", head->magic);
+                    break;
+                }
+                if (head->channel > NR_OF_CHANNELS) {
+                    ESP_LOGE(TAG, "invalid channel %x", head->channel);
+                    break;
+                }
+                if (head->size > SDIO_PAYLOAD || head->size > size_read) {
+                    ESP_LOGE(TAG, "invalid size %x", head->size);
+                    break;
+                }
                 ESP_LOG_BUFFER_HEXDUMP(TAG, rcv_buffer, size_read, ESP_LOG_VERBOSE);
-                esp_netif_receive(netif, rcv_buffer, size_read, NULL);
+                if (head->channel == 0) {
+                    esp_netif_receive(netif, rcv_buffer + sizeof(struct header), head->size, NULL);
+                } else {
+#if defined(CONFIG_EPPP_LINK_CHANNELS_SUPPORT)
+                    struct eppp_handle *h = esp_netif_get_io_driver(netif);
+                    if (h->channel_rx) {
+                        h->channel_rx(netif, head->channel, rcv_buffer + sizeof(struct header), head->size);
+                    }
+#endif
+                }
                 break;
             } else {
                 ESP_LOGE(TAG, "rx packet error: %08X", ret);

components/eppp_link/eppp_sdio_slave.c

@@ -10,9 +10,9 @@
 #include "esp_netif.h"
 #include "driver/sdio_slave.h"
 #include "eppp_link.h"
+#include "eppp_transport.h"
 #include "eppp_sdio.h"
 #include "esp_check.h"
-
 #if CONFIG_EPPP_LINK_DEVICE_SDIO_SLAVE
 #define BUFFER_NUM 4
 #define BUFFER_SIZE SDIO_PAYLOAD
@@ -21,19 +21,18 @@ static DMA_ATTR uint8_t sdio_slave_rx_buffer[BUFFER_NUM][BUFFER_SIZE];
 static DMA_ATTR uint8_t sdio_slave_tx_buffer[SDIO_PAYLOAD];
 static int s_slave_request = 0;
 
-esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len)
+static esp_err_t eppp_sdio_host_tx_generic(int channel, void *buffer, size_t len)
 {
     if (s_slave_request != REQ_INIT) {
         // silently skip the Tx if the SDIO not fully initialized
         return ESP_OK;
     }
-    memcpy(sdio_slave_tx_buffer, buffer, len);
-    size_t send_len = SDIO_ALIGN(len);
-    if (send_len > len) {
-        // pad with SOF's if the size is not 4 bytes aligned
-        memset(&sdio_slave_tx_buffer[len], PPP_SOF, send_len - len);
-    }
-
+    struct header *head = (void *)sdio_slave_tx_buffer;
+    head->magic = PPP_SOF;
+    head->channel = channel;
+    head->size = len;
+    memcpy(sdio_slave_tx_buffer + sizeof(struct header), buffer, len);
+    size_t send_len = SDIO_ALIGN(len + sizeof(struct header));
     ESP_LOG_BUFFER_HEXDUMP(TAG, sdio_slave_tx_buffer, send_len, ESP_LOG_VERBOSE);
     esp_err_t ret = sdio_slave_transmit(sdio_slave_tx_buffer, send_len);
     if (ret != ESP_OK) {
@@ -44,6 +43,18 @@ esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len)
     return ESP_OK;
 }
 
+esp_err_t eppp_sdio_slave_tx(void *h, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+esp_err_t eppp_sdio_transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    return eppp_sdio_host_tx_generic(channel, buffer, len);
+}
+#endif
+
 static esp_err_t slave_reset(void)
 {
     esp_err_t ret = ESP_OK;
@@ -82,7 +93,29 @@ esp_err_t eppp_sdio_slave_rx(esp_netif_t *netif)
     if (ret == ESP_ERR_NOT_FINISHED || ret == ESP_OK) {
 again:
         ptr = sdio_slave_recv_get_buf(handle, &length);
-        esp_netif_receive(netif, ptr, length, NULL);
+        struct header *head = (void *)ptr;
+        if (head->magic != PPP_SOF) {
+            ESP_LOGE(TAG, "invalid magic %x", head->magic);
+            return ESP_FAIL;
+        }
+        if (head->channel > NR_OF_CHANNELS) {
+            ESP_LOGE(TAG, "invalid channel %x", head->channel);
+            return ESP_FAIL;
+        }
+        if (head->size > SDIO_PAYLOAD || head->size > length) {
+            ESP_LOGE(TAG, "invalid size %x", head->size);
+            return ESP_FAIL;
+        }
+        if (head->channel == 0) {
+            esp_netif_receive(netif, ptr + sizeof(struct header), head->size, NULL);
+        } else {
+#if defined(CONFIG_EPPP_LINK_CHANNELS_SUPPORT)
+            struct eppp_handle *h = esp_netif_get_io_driver(netif);
+            if (h->channel_rx) {
+                h->channel_rx(netif, head->channel, ptr + sizeof(struct header), head->size);
+            }
+#endif
+        }
         if (sdio_slave_recv_load_buf(handle) != ESP_OK) {
             ESP_LOGE(TAG, "Failed to recycle packet buffer");
             return ESP_FAIL;

components/eppp_link/eppp_spi.c

@@ -6,6 +6,7 @@
 #include <string.h>
 #include <stdint.h>
 #include <inttypes.h>
+#include "sdkconfig.h"
 #include "esp_log.h"
 #include "esp_netif.h"
 #include "esp_check.h"
@@ -24,7 +25,8 @@
 
 #define MAX_PAYLOAD 1500
 #define MIN_TRIGGER_US 20
-#define SPI_HEADER_MAGIC 0x1234
+#define PPP_SOF 0x7E
+#define SPI_HEADER_MAGIC PPP_SOF
 #define SPI_ALIGN(size) (((size) + 3U) & ~(3U))
 #define TRANSFER_SIZE SPI_ALIGN((MAX_PAYLOAD + 6))
 #define NEXT_TRANSACTION_SIZE(a,b) (((a)>(b))?(a):(b)) /* next transaction: whichever is bigger */
@@ -32,10 +34,12 @@
 struct packet {
     size_t len;
     uint8_t *data;
+    int channel;
 };
 
 struct header {
-    uint16_t magic;
+    uint8_t magic;
+    uint8_t channel;
     uint16_t size;
     uint16_t next_size;
     uint16_t check;
@@ -65,12 +69,10 @@ struct eppp_spi {
     esp_timer_handle_t timer;
 };
 
-static esp_err_t transmit(void *h, void *buffer, size_t len)
+static esp_err_t transmit_generic(struct eppp_spi *handle, int channel, void *buffer, size_t len)
 {
-    struct eppp_handle *common = h;
-    struct eppp_spi *handle = __containerof(common, struct eppp_spi, parent);;
-#if CONFIG_EPPP_LINK_DEVICE_SPI
-    struct packet buf = { };
+
+    struct packet buf = { .channel = channel };
     uint8_t *current_buffer = buffer;
     size_t remaining = len;
     do {    // TODO(IDF-9194): Refactor this loop to allocate only once and perform
@@ -100,14 +102,25 @@ static esp_err_t transmit(void *h, void *buffer, size_t len)
         }
         gpio_set_level(handle->gpio_intr, 0);
     }
-
-#elif CONFIG_EPPP_LINK_DEVICE_UART
-    ESP_LOG_BUFFER_HEXDUMP("ppp_uart_send", buffer, len, ESP_LOG_WARN);
-    uart_write_bytes(handle->uart_port, buffer, len);
-#endif // DEVICE UART or SPI
     return ESP_OK;
 }
 
+static esp_err_t transmit(void *h, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = h;
+    struct eppp_spi *spi_handle = __containerof(handle, struct eppp_spi, parent);;
+    return transmit_generic(spi_handle, 0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+static esp_err_t transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = esp_netif_get_io_driver(netif);
+    struct eppp_spi *spi_handle = __containerof(handle, struct eppp_spi, parent);;
+    return transmit_generic(spi_handle, channel, buffer, len);
+}
+#endif
+
 static void IRAM_ATTR timer_callback(void *arg)
 {
     struct eppp_spi *h = arg;
@@ -339,6 +352,7 @@ esp_err_t eppp_perform(esp_netif_t *netif)
     if (h->outbound.len <= h->transaction_size && allow_test_tx == false) {
         // sending outbound
         head->size = h->outbound.len;
+        head->channel = h->outbound.channel;
         if (h->outbound.len > 0) {
             memcpy(out_buf + sizeof(struct header), h->outbound.data, h->outbound.len);
             free(h->outbound.data);
@@ -355,6 +369,7 @@ esp_err_t eppp_perform(esp_netif_t *netif)
     } else {
         // outbound is bigger, need to transmit in another transaction (keep this empty)
         head->size = 0;
+        head->channel = 0;
     }
     next_tx_size = head->next_size = h->outbound.len;
     head->magic = SPI_HEADER_MAGIC;
@@ -367,17 +382,25 @@ esp_err_t eppp_perform(esp_netif_t *netif)
     }
     head = (void *)in_buf;
     uint16_t check = esp_rom_crc16_le(0, in_buf, sizeof(struct header) - sizeof(uint16_t));
-    if (check != head->check || head->magic != SPI_HEADER_MAGIC) {
+    if (check != head->check || head->magic != SPI_HEADER_MAGIC || head->channel > NR_OF_CHANNELS) {
         h->transaction_size = 0; // need to start with HEADER only transaction
         if (allow_test_tx) {
             return ESP_OK;
         }
-        ESP_LOGE(TAG, "Wrong checksum or magic");
+        ESP_LOGE(TAG, "Wrong checksum, magic, or channel: %x %x %x", check, head->magic, head->channel);
         return ESP_FAIL;
     }
     if (head->size > 0) {
         ESP_LOG_BUFFER_HEXDUMP(TAG, in_buf + sizeof(struct header), head->size, ESP_LOG_VERBOSE);
-        esp_netif_receive(netif, in_buf + sizeof(struct header), head->size, NULL);
+        if (head->channel == 0) {
+            esp_netif_receive(netif, in_buf + sizeof(struct header), head->size, NULL);
+        } else {
+#if defined(CONFIG_EPPP_LINK_CHANNELS_SUPPORT)
+            if (h->parent.channel_rx) {
+                h->parent.channel_rx(netif, head->channel, in_buf + sizeof(struct header), head->size);
+            }
+#endif
+        }
     }
     h->transaction_size = NEXT_TRANSACTION_SIZE(next_tx_size, head->next_size);
     return ESP_OK;
@@ -415,6 +438,9 @@ eppp_transport_handle_t eppp_spi_init(struct eppp_config_spi_s *config)
     ESP_RETURN_ON_FALSE(config, NULL, TAG, "Config cannot be null");
     struct eppp_spi *h = calloc(1, sizeof(struct eppp_spi));
     ESP_RETURN_ON_FALSE(h, NULL, TAG, "Failed to allocate eppp_handle");
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    h->parent.channel_tx = transmit_channel;
+#endif
     h->is_master = config->is_master;
     h->parent.base.post_attach = post_attach;
     h->out_queue = xQueueCreate(CONFIG_EPPP_LINK_PACKET_QUEUE_SIZE, sizeof(struct packet));

components/eppp_link/eppp_transport.h

@@ -5,6 +5,13 @@
  */
 #pragma once
 #include "esp_netif_types.h"
+#include "sdkconfig.h"
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+#define NR_OF_CHANNELS CONFIG_EPPP_LINK_NR_OF_CHANNELS
+#else
+#define NR_OF_CHANNELS 1
+#endif
 
 struct eppp_handle {
     esp_netif_driver_base_t base;
@@ -12,6 +19,11 @@ struct eppp_handle {
     bool stop;
     bool exited;
     bool netif_stop;
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    eppp_channel_fn_t channel_tx;
+    eppp_channel_fn_t channel_rx;
+    void* context;
+#endif
 };
 
 esp_err_t eppp_check_connection(esp_netif_t *netif);

components/eppp_link/eppp_uart.c

@@ -31,19 +31,19 @@ struct eppp_uart {
 
 struct header {
     uint8_t magic;
+    uint8_t channel;
     uint8_t check;
     uint16_t size;
 } __attribute__((packed));
 
-static esp_err_t transmit(void *h, void *buffer, size_t len)
+static esp_err_t transmit_generic(struct eppp_uart *handle, int channel, void *buffer, size_t len)
 {
-    struct eppp_handle *common = h;
-    struct eppp_uart *handle = __containerof(common, struct eppp_uart, parent);
 #ifndef CONFIG_EPPP_LINK_USES_PPP
     static uint8_t out_buf[MAX_PACKET_SIZE] = {};
     struct header *head = (void *)out_buf;
     head->magic = HEADER_MAGIC;
     head->check = 0;
+    head->channel = channel;
     head->size = len;
     head->check = (0xFF & len) ^ (len >> 8);
     memcpy(out_buf + sizeof(struct header), buffer, len);
@@ -56,6 +56,22 @@ static esp_err_t transmit(void *h, void *buffer, size_t len)
     return ESP_OK;
 }
 
+static esp_err_t transmit(void *h, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = h;
+    struct eppp_uart *uart_handle = __containerof(handle, struct eppp_uart, parent);
+    return transmit_generic(uart_handle, 0, buffer, len);
+}
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+static esp_err_t transmit_channel(esp_netif_t *netif, int channel, void *buffer, size_t len)
+{
+    struct eppp_handle *handle = esp_netif_get_io_driver(netif);
+    struct eppp_uart *uart_handle = __containerof(handle, struct eppp_uart, parent);
+    return transmit_generic(uart_handle, channel, buffer, len);
+}
+#endif
+
 static esp_err_t init_uart(struct eppp_uart *h, struct eppp_config_uart_s *config)
 {
     h->uart_port = config->port;
@@ -122,6 +138,7 @@ static void process_packet(esp_netif_t *netif, uart_port_t uart_port, size_t ava
 
         // Check if we have the complete packet
         uint16_t payload_size = head->size;
+        int channel = head->channel;
         size_t total_packet_size = sizeof(struct header) + payload_size;
 
         if (payload_size > MAX_PAYLOAD) {
@@ -136,7 +153,15 @@ static void process_packet(esp_netif_t *netif, uart_port_t uart_port, size_t ava
         }
 
         // Got a complete packet, pass it to network
-        esp_netif_receive(netif, in_buf + buf_start + sizeof(struct header), payload_size, NULL);
+        if (channel == 0) {
+            esp_netif_receive(netif, in_buf + buf_start + sizeof(struct header), payload_size, NULL);
+        } else {
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+            if (h->parent.channel_rx) {
+                h->parent.channel_rx(netif, channel, in_buf + buf_start + sizeof(struct header), payload_size);
+            }
+#endif
+        }
 
         // Advance start pointer past this packet
         buf_start += total_packet_size;
@@ -237,6 +262,9 @@ eppp_transport_handle_t eppp_uart_init(struct eppp_config_uart_s *config)
     ESP_RETURN_ON_FALSE(config, NULL, TAG, "Config cannot be null");
     struct eppp_uart *h = calloc(1, sizeof(struct eppp_uart));
     ESP_RETURN_ON_FALSE(h, NULL, TAG, "Failed to allocate eppp_handle");
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+    h->parent.channel_tx = transmit_channel;
+#endif
     h->parent.base.post_attach = post_attach;
     ESP_GOTO_ON_ERROR(init_uart(h, config), err, TAG, "Failed to init UART");
     return &h->parent;

components/eppp_link/examples/host/main/CMakeLists.txt

@@ -1,2 +1,6 @@
+if(CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL)
+    set(wifi_over_channels channel_wifi_station.c)
+endif()
 idf_component_register(SRCS app_main.c register_iperf.c
-                    INCLUDE_DIRS ".")
+                            ${wifi_over_channels}
+                       INCLUDE_DIRS ".")

components/eppp_link/examples/host/main/Kconfig.projbuild

@@ -106,4 +106,14 @@ menu "Example Configuration"
         help
             Baudrate used by the PPP over UART
 
+    config EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+        bool "Use WiFi over EPPP channel"
+        default n
+        depends on EPPP_LINK_CHANNELS_SUPPORT && ESP_WIFI_REMOTE_ENABLED
+        help
+            Enable this option to use WiFi over EPPP channel.
+            If this option is enabled, the example will only start the Wi-Fi driver,
+            but the Wi-Fi netif will reside on client's end and will channel
+            the Rx and Tx data via EPPP channels.
+
 endmenu

components/eppp_link/examples/host/main/app_main.c

@@ -14,6 +14,7 @@
 #include "esp_netif.h"
 #include "eppp_link.h"
 #include "esp_log.h"
+#include "esp_check.h"
 #include "mqtt_client.h"
 #include "console_ping.h"
 
@@ -88,6 +89,7 @@ static void mqtt_app_start(void)
 }
 #endif // MQTT
 
+void station_over_eppp_channel(void *arg);
 
 void app_main(void)
 {
@@ -156,6 +158,9 @@ void app_main(void)
     // start console REPL
     ESP_ERROR_CHECK(console_cmd_start());
 
+#ifdef CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+    station_over_eppp_channel(eppp_netif);
+#endif
 #if CONFIG_EXAMPLE_MQTT
     mqtt_app_start();
 #endif

components/eppp_link/examples/host/main/channel_wifi_station.c

@@ -0,0 +1,185 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include <stdio.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+#include "esp_system.h"
+#include "esp_event.h"
+#include "esp_netif.h"
+#include "eppp_link.h"
+#include "esp_log.h"
+#include "esp_check.h"
+#include "esp_wifi_remote.h"
+
+#define CHAT_CHANNEL 1
+#define WIFI_CHANNEL 2
+
+typedef enum {
+    UNKNOWN,
+    HELLO,
+    START,
+    ERROR,
+} state_t;
+
+typedef struct context {
+    eppp_channel_fn_t transmit;
+    EventGroupHandle_t flags;
+    state_t state;
+    esp_netif_t *eppp;
+} context_t;
+
+#define HELLO_BIT BIT0
+#define START_BIT BIT1
+#define CONNECT_BIT BIT2
+#define SERVER_UP_BIT BIT3
+
+#define ALL_BITS (HELLO_BIT | START_BIT | CONNECT_BIT | SERVER_UP_BIT)
+
+static uint8_t s_wifi_mac_addr[6] = { 0 };
+static const char *TAG = "eppp_host_example_with_channels";
+
+esp_netif_t* esp_wifi_remote_create_default_sta(void);
+
+static void event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
+{
+    ESP_LOGI(TAG, "IP event_handler: event_base=%s event_id=%d", event_base, event_id);
+    if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
+        ip_event_got_ip_t *event = (ip_event_got_ip_t *) event_data;
+        ESP_LOGI(TAG, "Got IP:" IPSTR, IP2STR(&event->ip_info.ip));
+    }
+}
+
+esp_err_t esp_wifi_remote_get_mac(wifi_interface_t ifx, uint8_t mac[6])
+{
+    if (ifx != WIFI_IF_STA) {
+        return ESP_ERR_INVALID_STATE;
+
+    }
+    for (int i = 0; i < sizeof(s_wifi_mac_addr); i++) {
+        if (s_wifi_mac_addr[i] == 0) {
+            return ESP_ERR_INVALID_STATE;
+        }
+    }
+    memcpy(mac, s_wifi_mac_addr, sizeof(s_wifi_mac_addr));
+    return ESP_OK;
+}
+
+static esp_err_t eppp_receive(esp_netif_t *netif, int nr, void *buffer, size_t len)
+{
+    context_t *ctx = eppp_get_context(netif);
+    if (nr == CHAT_CHANNEL) {
+        ESP_LOGI(TAG, "Received channel=%d len=%d %.*s", nr, (int)len, (int)len, (char *)buffer);
+        const char hello[] = "Hello client";
+        const char mac[] = "MAC: ";
+        const char connected[] = "Connected";
+        const char server_up[] = "Server up";
+        size_t mac_len = 5 /* MAC: */ + 6 * 2 /* 6 bytes per char */ + 5 /* : */ + 1 /* \0 */;
+        if (len == sizeof(server_up) && memcmp(buffer, server_up, len) == 0) {
+            if (ctx->state == UNKNOWN) {
+                ESP_LOGI(TAG, "Server is up");
+                ctx->state = HELLO;
+            } else {
+                ESP_LOGE(TAG, "Received server up in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+            xEventGroupSetBits(ctx->flags, SERVER_UP_BIT);
+        } else if (len == sizeof(hello) && memcmp(buffer, hello, len) == 0) {
+            if (ctx->state == HELLO) {
+                xEventGroupSetBits(ctx->flags, HELLO_BIT);
+            } else {
+                ESP_LOGE(TAG, "Received hello in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+        } else if (len == mac_len && memcmp(buffer, mac, 5) == 0) {
+            if (ctx->state == HELLO) {
+                uint8_t mac_addr[6];
+                sscanf((char *)buffer + 5, "%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8 ":%2" PRIx8,
+                       &mac_addr[0], &mac_addr[1], &mac_addr[2], &mac_addr[3], &mac_addr[4], &mac_addr[5]);
+                ESP_LOGI(TAG, "Parsed MAC: %02x:%02x:%02x:%02x:%02x:%02x\n", mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
+                memcpy(s_wifi_mac_addr, mac_addr, sizeof(s_wifi_mac_addr));
+                xEventGroupSetBits(ctx->flags, START_BIT);
+            } else {
+                ESP_LOGE(TAG, "Received MAC in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+        } else if (len == sizeof(connected) && memcmp(buffer, connected, len) == 0) {
+            if (ctx->state == START) {
+                xEventGroupSetBits(ctx->flags, CONNECT_BIT);
+            } else {
+                ESP_LOGE(TAG, "Received connected in unexpected state %d", ctx->state);
+                ctx->state = ERROR;
+            }
+        }
+    } else if (nr == WIFI_CHANNEL) {
+        ESP_LOGD(TAG, "Received WIFI channel=%d len=%d", nr, (int)len);
+        ESP_LOG_BUFFER_HEXDUMP("wifi-receive", buffer, len, ESP_LOG_VERBOSE);
+        return esp_wifi_remote_channel_rx(ctx->eppp, buffer, NULL, len);
+    } else {
+        ESP_LOGE(TAG, "Incorrect channel number %d", nr);
+        return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+static esp_err_t wifi_transmit(void *h, void *buffer, size_t len)
+{
+    esp_netif_t *eppp = (esp_netif_t *)h;
+    context_t *ctx = eppp_get_context(eppp);
+    ESP_LOG_BUFFER_HEXDUMP("wifi-transmit", buffer, len, ESP_LOG_VERBOSE);
+    return ctx->transmit(eppp, WIFI_CHANNEL, buffer, len);
+}
+
+void esp_netif_destroy_wifi_remote(void *esp_netif);
+
+void station_over_eppp_channel(void *arg)
+{
+    __attribute__((unused)) esp_err_t ret;
+    esp_netif_t *wifi = NULL;
+    context_t ctx = {
+        .transmit = NULL,
+        .flags = NULL,
+        .state = UNKNOWN,
+        .eppp = (esp_netif_t *)arg
+    };
+    ESP_GOTO_ON_FALSE(ctx.eppp != NULL, ESP_FAIL, err, TAG, "Incorrect EPPP netif");
+    ESP_GOTO_ON_FALSE(ctx.flags = xEventGroupCreate(), ESP_FAIL, err, TAG, "Failed to create event group");
+    ESP_GOTO_ON_ERROR(eppp_add_channels(ctx.eppp, &ctx.transmit, eppp_receive, &ctx), err, TAG, "Failed to add channels");
+    ESP_GOTO_ON_FALSE(ctx.transmit, ESP_FAIL, err, TAG, "Channel tx function is not set");
+    ESP_GOTO_ON_ERROR(esp_wifi_remote_channel_set(WIFI_IF_STA, ctx.eppp, wifi_transmit), err, TAG, "Failed to set wifi channel tx function");
+    esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, event_handler, &ctx);
+
+    while (1) {
+        EventBits_t bits = xEventGroupWaitBits(ctx.flags, ALL_BITS, pdTRUE, pdFALSE, pdMS_TO_TICKS(1000));
+        if (bits & HELLO_BIT) {
+            ESP_LOGI(TAG, "Hello done");
+            if (wifi == NULL) {
+                wifi = esp_wifi_remote_create_default_sta();
+            }
+            const char command[] = "Get MAC";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)command, sizeof(command));
+        } else if (bits & START_BIT) {
+            ctx.state = START;
+            ESP_LOGI(TAG, "Starting WIFI");
+            esp_event_post(WIFI_REMOTE_EVENT, WIFI_EVENT_STA_START, NULL, 0, 0);
+        } else if (bits & CONNECT_BIT) {
+            ESP_LOGI(TAG, "WIFI connected");
+            esp_event_post(WIFI_REMOTE_EVENT, WIFI_EVENT_STA_CONNECTED, NULL, 0, 0);
+        } else if ((bits & SERVER_UP_BIT) == SERVER_UP_BIT || ctx.state != START)  {
+            if (ctx.state == ERROR) {
+                esp_netif_destroy_wifi_remote(wifi);
+                wifi = NULL;
+                ESP_LOGI(TAG, "WiFi netif has been destroyed");
+            }
+            const char hello[] = "Hello server";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)hello, sizeof(hello));
+            ctx.state = HELLO;
+        }
+    }
+
+err:
+    vTaskDelete(NULL);
+}

components/eppp_link/examples/host/main/idf_component.yml

@@ -1,7 +1,7 @@
 dependencies:
-  espressif/iperf-cmd: "^0.1.1"
+  espressif/iperf-cmd: ^0.1.1
   espressif/eppp_link:
-    version: "*"
-    override_path: "../../.."
+    version: '*'
+    override_path: ../../..
   console_cmd_ping:
-    version: "*"
+    version: '*'

components/eppp_link/examples/slave/main/CMakeLists.txt

@@ -1,2 +1,6 @@
-idf_component_register(SRCS "eppp_slave.c"
-                    INCLUDE_DIRS ".")
+if(CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL)
+    set(wifi_over_channels channel_wifi_station.c)
+endif()
+idf_component_register(SRCS eppp_slave.c
+                            ${wifi_over_channels}
+                       INCLUDE_DIRS ".")

components/eppp_link/examples/slave/main/Kconfig.projbuild

@@ -98,4 +98,14 @@ menu "Example Configuration"
         help
             Baudrate used by the PPP over UART
 
+    config EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+        bool "Use WiFi over EPPP channel"
+        default n
+        depends on EPPP_LINK_CHANNELS_SUPPORT
+        help
+            Enable this option to use WiFi over EPPP channel.
+            If this option is enabled, the example will only start the Wi-Fi driver,
+            but the Wi-Fi netif will reside on client's end and will channel
+            the Rx and Tx data via EPPP channels.
+
 endmenu

components/eppp_link/examples/slave/main/channel_wifi_station.c

@@ -0,0 +1,169 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include <stdio.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+#include "esp_system.h"
+#include "esp_event.h"
+#include "esp_netif.h"
+#include "eppp_link.h"
+#include "esp_log.h"
+#include "esp_check.h"
+#include "esp_private/wifi.h"
+
+#define CHAT_CHANNEL 1
+#define WIFI_CHANNEL 2
+
+typedef enum {
+    UNKNOWN,
+    HELLO,
+    START,
+    ERROR,
+} state_t;
+
+typedef struct context {
+    eppp_channel_fn_t transmit;
+    EventGroupHandle_t flags;
+    state_t state;
+    esp_netif_t *eppp;
+} context_t;
+
+#define HELLO_BIT BIT0
+#define START_BIT BIT1
+#define CONNECT_BIT BIT2
+#define DISCONNECT_BIT BIT3
+
+#define ALL_BITS (HELLO_BIT | START_BIT | CONNECT_BIT | DISCONNECT_BIT)
+
+static const char *TAG = "eppp_host_example_with_channels";
+static context_t *s_eppp_channel_ctx = NULL;
+
+static esp_err_t eppp_receive(esp_netif_t *netif, int nr, void *buffer, size_t len)
+{
+    context_t *ctx = eppp_get_context(netif);
+    if (nr == CHAT_CHANNEL) {
+        ESP_LOGI(TAG, "Received channel=%d len=%d %.*s", nr, (int)len, (int)len, (char *)buffer);
+        const char hello[] = "Hello server";
+        const char mac[] = "Get MAC";
+        if (len == sizeof(hello) && memcmp(buffer, hello, len) == 0) {
+            if (ctx->state == HELLO) {
+                xEventGroupSetBits(ctx->flags, HELLO_BIT);
+            } else {
+                ctx->state = ERROR;
+            }
+        } else if (len == sizeof(mac) && memcmp(buffer, mac, 5) == 0) {
+            if (ctx->state == HELLO) {
+                xEventGroupSetBits(ctx->flags, START_BIT);
+            } else {
+                ctx->state = ERROR;
+            }
+        }
+    } else if (nr == WIFI_CHANNEL) {
+        ESP_LOGD(TAG, "Received WIFI channel=%d len=%d", nr, (int)len);
+        ESP_LOG_BUFFER_HEXDUMP("wifi-receive", buffer, len, ESP_LOG_VERBOSE);
+        return esp_wifi_internal_tx(WIFI_IF_STA, buffer, len);
+    } else {
+        ESP_LOGE(TAG, "Incorrect channel number %d", nr);
+        return ESP_FAIL;
+    }
+    return ESP_OK;
+}
+
+static esp_err_t wifi_receive(void *buffer, uint16_t len, void *eb)
+{
+    s_eppp_channel_ctx->transmit(s_eppp_channel_ctx->eppp, WIFI_CHANNEL, buffer, len);
+    esp_wifi_internal_free_rx_buffer(eb);
+    return ESP_OK;
+}
+
+static void event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
+{
+    context_t *ctx = arg;
+    ESP_LOGI(TAG, "event_handler: event_base=%s event_id=%d", event_base, event_id);
+    if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
+        ESP_LOGI(TAG, "WIFI start event");
+        esp_wifi_connect();
+        xEventGroupSetBits(ctx->flags, CONNECT_BIT);
+    } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
+        ESP_LOGI(TAG, "connect to the AP fail");
+        xEventGroupSetBits(ctx->flags, DISCONNECT_BIT);
+    }
+}
+
+
+static void init_wifi_driver(context_t *ctx)
+{
+    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
+    ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID,
+                                               event_handler, ctx));
+    wifi_config_t wifi_config = {
+        .sta = {
+            .ssid = CONFIG_ESP_WIFI_SSID,
+            .password = CONFIG_ESP_WIFI_PASSWORD,
+        },
+    };
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config));
+}
+
+void station_over_eppp_channel(void *arg)
+{
+    __attribute__((unused)) esp_err_t ret;
+    context_t ctx = {
+        .transmit = NULL,
+        .flags = NULL,
+        .state = UNKNOWN,
+        .eppp = (esp_netif_t *)arg
+    };
+    ESP_GOTO_ON_FALSE(ctx.flags = xEventGroupCreate(), ESP_FAIL, err, TAG, "Failed to create event group");
+    ESP_GOTO_ON_ERROR(eppp_add_channels(ctx.eppp, &ctx.transmit, eppp_receive, &ctx), err, TAG, "Failed to add channels");
+    ESP_GOTO_ON_FALSE(ctx.transmit, ESP_FAIL, err, TAG, "Channel tx function is not set");
+    init_wifi_driver(&ctx);
+
+    while (1) {
+        EventBits_t bits = xEventGroupWaitBits(ctx.flags, ALL_BITS, pdTRUE, pdFALSE, pdMS_TO_TICKS(1000));
+        if (bits & HELLO_BIT) {
+            ESP_LOGI(TAG, "Hello from client received");
+            const char hello[] = "Hello client";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)hello, sizeof(hello));
+        } else if (bits & START_BIT) {
+            ctx.state = START;
+            ESP_LOGI(TAG, "Starting WIFI");
+            uint8_t mac[6];
+            if (esp_wifi_get_mac(WIFI_IF_STA, mac) != ESP_OK) {
+                ESP_LOGE(TAG, "esp_wifi_get_mac failed");
+                ctx.state = ERROR;
+                continue;
+            }
+            char mac_data[5 /* MAC: */ + 6 * 2 /* 6 bytes per char */ + 5 /* : */ + 1 /* \0 */];
+            sprintf(mac_data, "MAC: %02x:%02x:%02x:%02x:%02x:%02x", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+            ESP_LOGI(TAG, "Sending MAC: %.*s", (int)sizeof(mac_data), mac_data);
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)mac_data, sizeof(mac_data));
+            ret = esp_wifi_start();
+            ESP_LOGI(TAG, "WIFI start result: %d", ret);
+            s_eppp_channel_ctx = &ctx;
+            esp_wifi_internal_reg_rxcb(WIFI_IF_STA, wifi_receive);
+        } else if (bits & CONNECT_BIT) {
+            ESP_LOGI(TAG, "WIFI connected");
+            const char connected[] = "Connected";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)connected, sizeof(connected));
+        } else if (bits & DISCONNECT_BIT) {
+            const char disconnected[] = "Disconnected";
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)disconnected, sizeof(disconnected));
+        } else if (ctx.state != START) {
+            ctx.state = HELLO;
+            const char up[] = "Server up";
+            esp_wifi_disconnect();
+            esp_wifi_stop();
+            ctx.transmit(ctx.eppp, CHAT_CHANNEL, (void*)up, sizeof(up));
+        }
+    }
+
+err:
+    vTaskDelete(NULL);
+}

components/eppp_link/examples/slave/main/eppp_slave.c

@@ -11,12 +11,14 @@
 #include "esp_wifi.h"
 #include "esp_event.h"
 #include "esp_log.h"
+#include "esp_check.h"
 #include "nvs_flash.h"
 #include "eppp_link.h"
+#include "inttypes.h"
 
 static const char *TAG = "eppp_slave";
 
-#if CONFIG_SOC_WIFI_SUPPORTED
+#if defined(CONFIG_SOC_WIFI_SUPPORTED) && !defined(CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL)
 
 /* FreeRTOS event group to signal when we are connected*/
 static EventGroupHandle_t s_wifi_event_group;
@@ -27,12 +29,13 @@ static EventGroupHandle_t s_wifi_event_group;
 #define WIFI_CONNECTED_BIT BIT0
 #define WIFI_FAIL_BIT      BIT1
 
-
 static int s_retry_num = 0;
 
 static void event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data)
 {
+    ESP_LOGI(TAG, "event_handler: event_base=%s event_id=%" PRIi32, event_base, event_id);
     if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
+        ESP_LOGI(TAG, "WIFI start event");
         esp_wifi_connect();
     } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
         if (s_retry_num < CONFIG_ESP_MAXIMUM_RETRY) {
@@ -107,12 +110,15 @@ void init_network_interface(void)
 }
 #else
 
+// If the SoC does not have WiFi capabilities, we can initialize a different network interface, this function is a placeholder for that purpose.
+// This function is also a no-op if EXAMPLE_WIFI_OVER_EPPP_CHANNEL==1, since the Wi-Fi network interface will live on the other peer (on the host side).
 void init_network_interface(void)
 {
-    // placeholder to initialize any other network interface if WiFi is not available
 }
 
-#endif // SoC WiFi capable chip
+#endif // SoC WiFi capable chip || WiFi over EPPP channel
+
+void station_over_eppp_channel(void *arg);
 
 void app_main(void)
 {
@@ -153,5 +159,9 @@ void app_main(void)
         ESP_LOGE(TAG, "Failed to setup connection");
         return ;
     }
+#ifdef CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL
+    station_over_eppp_channel(eppp_netif);
+#else
     ESP_ERROR_CHECK(esp_netif_napt_enable(eppp_netif));
+#endif // CONFIG_EXAMPLE_WIFI_OVER_EPPP_CHANNEL
 }

components/eppp_link/idf_component.yml

@@ -1,4 +1,4 @@
-version: 0.3.0
+version: 1.0.0
 url: https://github.com/espressif/esp-protocols/tree/master/components/eppp_link
 description: The component provides a general purpose PPP connectivity, typically used as WiFi-PPP router
 dependencies:

components/eppp_link/include/eppp_link.h

@@ -5,6 +5,10 @@
  */
 #pragma once
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #define EPPP_DEFAULT_SERVER_IP() ESP_IP4TOADDR(192, 168, 11, 1)
 #define EPPP_DEFAULT_CLIENT_IP() ESP_IP4TOADDR(192, 168, 11, 2)
 
@@ -110,7 +114,6 @@ typedef enum eppp_transport {
 
 typedef struct eppp_config_t {
     eppp_transport_t transport;
-
     struct eppp_config_spi_s {
         int host;
         bool is_master;
@@ -203,3 +206,15 @@ void eppp_netif_deinit(esp_netif_t *netif);
  *  - ESP_ERR_TIMEOUT indicates that the operation was requested to stop
  */
 esp_err_t eppp_perform(esp_netif_t *netif);
+
+#ifdef CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+typedef esp_err_t (*eppp_channel_fn_t)(esp_netif_t *netif, int nr, void *buffer, size_t len);
+
+esp_err_t eppp_add_channels(esp_netif_t *netif, eppp_channel_fn_t *tx, const eppp_channel_fn_t rx, void* context);
+
+void* eppp_get_context(esp_netif_t *netif);
+#endif // CONFIG_EPPP_LINK_CHANNELS_SUPPORT
+
+#ifdef __cplusplus
+}
+#endif

components/esp_dns/esp_dns_doh.c

@@ -177,6 +177,9 @@ esp_err_t esp_dns_http_event_handler(esp_http_client_event_t *evt)
     case HTTP_EVENT_REDIRECT:
         ESP_LOGE(TAG, "HTTP_EVENT_REDIRECT: Not supported(%d)", esp_http_client_get_status_code(evt->client));
         break;
+    default:
+        ESP_LOGD(TAG, "Other HTTP event: %d", evt->event_id);
+        break;
     }
     return ESP_OK;
 }

components/esp_modem/examples/modem_tcp_client/main/sock_commands_bg96.cpp

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -18,14 +18,14 @@ using namespace esp_modem;
 
 command_result net_open(CommandableIf *t)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     std::string out;
     auto ret = dce_commands::generic_get_string(t, "AT+QISTATE?\r", out, 1000);
     if (ret != command_result::OK) {
         return ret;
     }
     if (out.find("+QISTATE: 0") != std::string::npos) {
-        ESP_LOGV(TAG, "%s", out.data() );
+        ESP_LOGV(TAG, "%s", out.data());
         ESP_LOGD(TAG, "Already there");
         return command_result::FAIL;
     } else if (out.empty()) {
@@ -36,7 +36,7 @@ command_result net_open(CommandableIf *t)
 
 command_result net_close(CommandableIf *t)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     dce_commands::generic_command(t, "AT+QICLOSE=0\r", "OK", "ERROR", 10000);
     esp_modem::Task::Delay(1000);
     return dce_commands::generic_command(t, "AT+QIDEACT=1\r", "OK", "ERROR", 40000);
@@ -44,11 +44,11 @@ command_result net_close(CommandableIf *t)
 
 command_result tcp_open(CommandableIf *t, const std::string &host, int port, int timeout)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     std::string ip_open = R"(AT+QIOPEN=1,0,"TCP",")" + host + "\"," + std::to_string(port) + "\r";
     auto ret = dce_commands::generic_command(t, ip_open, "+QIOPEN: 0,0", "ERROR", timeout);
     if (ret != command_result::OK) {
-        ESP_LOGE(TAG, "%s Failed", __func__ );
+        ESP_LOGE(TAG, "%s Failed", __func__);
         return ret;
     }
     return command_result::OK;
@@ -56,27 +56,27 @@ command_result tcp_open(CommandableIf *t, const std::string &host, int port, int
 
 command_result tcp_close(CommandableIf *t)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     return dce_commands::generic_command(t, "AT+QICLOSE=0\r", "OK", "ERROR", 10000);
 }
 
 command_result tcp_send(CommandableIf *t, uint8_t *data, size_t len)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     assert(0);      // Remove when fix done
     return command_result::FAIL;
 }
 
 command_result tcp_recv(CommandableIf *t, uint8_t *data, size_t len, size_t &out_len)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     assert(0);      // Remove when fix done
     return command_result::FAIL;
 }
 
 command_result get_ip(CommandableIf *t, std::string &ip)
 {
-    ESP_LOGV(TAG, "%s", __func__ );
+    ESP_LOGV(TAG, "%s", __func__);
     std::string out;
     auto ret = dce_commands::generic_get_string(t, "AT+QIACT?\r", out, 5000);
     if (ret != command_result::OK) {
@@ -130,12 +130,15 @@ Responder::ret Responder::recv(uint8_t *data, size_t len)
     auto *recv_data = (char *)data;
     if (data_to_recv == 0) {
         const std::string_view head = "+QIRD: ";
-        auto head_pos = std::search(recv_data, recv_data + len, head.begin(), head.end());
-        if (head_pos == recv_data + len) {
+        const std::string_view recv_data_view = std::string_view(recv_data, len);
+        auto head_pos_found = recv_data_view.find(head);
+        if (head_pos_found == std::string_view::npos) {
             return ret::FAIL;
         }
 
+        auto *head_pos = recv_data + head_pos_found;
         auto next_nl = (char *)memchr(head_pos + head.size(), '\n', MIN_MESSAGE);
+
         if (next_nl == nullptr) {
             return ret::FAIL;
         }

components/esp_modem/examples/pppos_client/main/Kconfig.projbuild

@@ -185,7 +185,7 @@ menu "Example Configuration"
 
     config EXAMPLE_MQTT_BROKER_URI
         string "MQTT Broker URL"
-        default "mqtt://mqtt.eclipseprojects.io"
+        default "mqtt://test.mosquitto.org"
         help
             URL of the mqtt broker which this example connects to.
 

components/esp_modem/examples/simple_cmux_client/sdkconfig.ci.sim800_cmux

@@ -16,4 +16,4 @@ CONFIG_COMPILER_CXX_EXCEPTIONS=y
 CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
 CONFIG_EXAMPLE_CLOSE_CMUX_AT_END=y
 CONFIG_EXAMPLE_MQTT_TEST_TOPIC="/ci/esp-modem/pppos-client"
-CONFIG_BROKER_URI="mqtt://mqtt.eclipseprojects.io"
+CONFIG_BROKER_URI="mqtt://test.mosquitto.org"

components/esp_modem/src/esp_modem_command_library.cpp

@@ -635,17 +635,40 @@ command_result get_network_registration_state(CommandableIf *t, int &state)
     }
 
     constexpr std::string_view pattern = "+CEREG: ";
-    int state_pos_start;
-    int state_pos_end;
-    if (out.find(pattern) == std::string::npos || (state_pos_start = out.find(',')) == std::string::npos) {
+
+    // Check if pattern exists and find its position
+    size_t pattern_pos = out.find(pattern);
+    if (pattern_pos == std::string::npos) {
         return command_result::FAIL;
     }
 
-    if (out.find(pattern) == std::string::npos || (state_pos_end = out.find(',', state_pos_start)) == std::string::npos) {
-        if (std::from_chars(out.data() + state_pos_start, out.data() + out.size(), state).ec == std::errc::invalid_argument) {
-            return command_result::FAIL;
+    // Find the first comma after the pattern
+    size_t state_pos_start = out.find(',', pattern_pos);
+    if (state_pos_start == std::string::npos) {
+        return command_result::FAIL;
+    }
+
+    // Find the end of the state value - either a second comma or end of line
+    size_t state_pos_end = out.find(',', state_pos_start + 1);
+    if (state_pos_end == std::string::npos) {
+        // No second comma found, look for end of line characters
+        state_pos_end = out.find('\r', state_pos_start);
+        if (state_pos_end == std::string::npos) {
+            state_pos_end = out.find('\n', state_pos_start);
         }
-    } else if (std::from_chars(out.data() + state_pos_start, out.data() + state_pos_end, state).ec == std::errc::invalid_argument) {
+        if (state_pos_end == std::string::npos) {
+            // No end delimiter found, use end of string
+            state_pos_end = out.size();
+        }
+    }
+
+    // Validate that we have a valid range to parse
+    if (state_pos_start + 1 >= state_pos_end) {
+        return command_result::FAIL;
+    }
+
+    // Extract state value (skip the comma)
+    if (std::from_chars(out.data() + state_pos_start + 1, out.data() + state_pos_end, state).ec == std::errc::invalid_argument) {
         return command_result::FAIL;
     }
 

components/esp_modem/src/esp_modem_dce.cpp

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -283,6 +283,10 @@ namespace ppp {
 // Test that we're in the PPP mode by sending an LCP protocol echo request and expecting LCP echo reply
 constexpr std::array<uint8_t, 16> lcp_echo_request = {0x7e, 0xff, 0x03, 0xc0, 0x21, 0x09, 0x01, 0x00, 0x08, 0x99, 0xd1, 0x35, 0xc1, 0x8e, 0x2c, 0x7e };
 constexpr std::array<uint8_t, 5> lcp_echo_reply_head = {0x7e, 0xff, 0x7d, 0x23, 0xc0};
+// PPP frame delimiter
+constexpr uint8_t ppp_delimiter = 0x7e;
+// LCP protocol ID
+constexpr std::array<uint8_t, 2> lcp_protocol_id = {0xc0, 0x21};
 const size_t mode = 1 << 0;
 const int timeout = 200;
 }
@@ -325,27 +329,48 @@ modem_mode DCE_Mode::guess_unsafe(DTE *dte, bool with_cmux)
         ESP_LOG_BUFFER_HEXDUMP("esp-modem: guess mode data:", reply, reply_pos, ESP_LOG_DEBUG);
 
         // Check whether the response resembles the "golden" reply (for these 3 protocols)
-        if (reply_pos >= sizeof(probe::ppp::lcp_echo_reply_head)) {
-            // check for initial 2 bytes
-            auto *ptr = static_cast<uint8_t *>(memmem(reply, reply_pos, probe::ppp::lcp_echo_reply_head.data(), 2));
-            // and check the other two bytes for protocol ID:
-            // * either LCP reply
-            if (ptr && ptr[3] == probe::ppp::lcp_echo_reply_head[3] && ptr[4] == probe::ppp::lcp_echo_reply_head[4]) {
-                if (auto signal = weak_signal.lock()) {
-                    signal->set(probe::ppp::mode);
-                }
-            }
-            // * or LCP conf request
-            if (ptr && ptr[3] == probe::ppp::lcp_echo_request[3] && ptr[4] == probe::ppp::lcp_echo_request[4]) {
-                if (auto signal = weak_signal.lock()) {
-                    signal->set(probe::ppp::mode);
+        if (reply_pos >= 3) { // Minimum size needed for basic PPP detection
+            // Check for PPP detection - look for both traditional format and alternative formats
+
+            // Look for PPP frame delimiter (0x7E)
+            auto *ppp_start = static_cast<uint8_t *>(memchr(reply, probe::ppp::ppp_delimiter, reply_pos));
+            if (ppp_start) {
+                size_t remaining = reply_pos - (ppp_start - reply);
+
+                // Look for LCP protocol ID anywhere within reasonable distance after delimiter
+                if (remaining >= 5) { // Reasonable minimum for finding protocol ID
+                    // Check for original expected pattern
+                    if (memmem(ppp_start, remaining, probe::ppp::lcp_echo_reply_head.data(), 2)) {
+                        // Check for protocol ID in original format position
+                        uint8_t *protocol_pos = ppp_start + 3;
+                        if ((protocol_pos + 1) < (reply + reply_pos) &&
+                                (protocol_pos[0] == probe::ppp::lcp_echo_reply_head[3] &&
+                                 protocol_pos[1] == probe::ppp::lcp_echo_reply_head[4])) {
+                            if (auto signal = weak_signal.lock()) {
+                                signal->set(probe::ppp::mode);
+                                return command_result::OK;
+                            }
+                        }
+                    }
+
+                    // Also check for direct LCP protocol ID after delimiter (alternative format)
+                    if (remaining >= 3 && memmem(ppp_start + 1, remaining - 1,
+                                                 probe::ppp::lcp_protocol_id.data(),
+                                                 probe::ppp::lcp_protocol_id.size())) {
+                        if (auto signal = weak_signal.lock()) {
+                            signal->set(probe::ppp::mode);
+                            return command_result::OK;
+                        }
+                    }
                 }
             }
         }
+
         if (reply_pos >= 4 && memmem(reply, reply_pos, probe::cmd::reply, sizeof(probe::cmd::reply))) {
             if (reply[0] != 0xf9) {   // double check that the reply is not wrapped in CMUX headers
                 if (auto signal = weak_signal.lock()) {
                     signal->set(probe::cmd::mode);
+                    return command_result::OK;
                 }
             }
         }
@@ -356,6 +381,7 @@ modem_mode DCE_Mode::guess_unsafe(DTE *dte, bool with_cmux)
             if (ptr && (ptr[3] >> 2) == 0) {
                 if (auto signal = weak_signal.lock()) {
                     signal->set(probe::cmux::mode);
+                    return command_result::OK;
                 }
             }
         }

components/esp_modem/src/esp_modem_dte.cpp

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -359,7 +359,6 @@ void DTE::on_read(got_line_cb on_read_cb)
         auto res = on_read_cb(data, len);
         if (res == command_result::OK || res == command_result::FAIL) {
             primary_term->set_read_cb(nullptr);
-            internal_lock.unlock();
             return true;
         }
         return false;
@@ -368,12 +367,14 @@ void DTE::on_read(got_line_cb on_read_cb)
 
 bool DTE::command_cb::process_line(uint8_t *data, size_t consumed, size_t len)
 {
+    // returning true indicates that the processing finished and lower layers can destroy the accumulated buffer
 #ifdef CONFIG_ESP_MODEM_URC_HANDLER
+    bool consume_buffer = false;
     if (urc_handler) {
-        urc_handler(data, consumed + len);
+        consume_buffer = urc_handler(data, consumed + len) != command_result::TIMEOUT;
     }
     if (result != command_result::TIMEOUT || got_line == nullptr) {
-        return false;   // this line has been processed already (got OK or FAIL previously)
+        return consume_buffer;   // this line has been processed already (got OK or FAIL previously)
     }
 #endif
     if (memchr(data + consumed, separator, len)) {

components/esp_modem/test/target_urc/CMakeLists.txt

@@ -0,0 +1,7 @@
+# The following lines of boilerplate have to be in your project's CMakeLists
+# in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.5)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+set(COMPONENTS main)
+project(urc_test)

components/esp_modem/test/target_urc/main/CMakeLists.txt

@@ -0,0 +1,2 @@
+idf_component_register(SRCS "urc_test.cpp"
+                       INCLUDE_DIRS ".")

components/esp_modem/test/target_urc/main/idf_component.yml

@@ -0,0 +1,7 @@
+## IDF Component Manager Manifest File
+dependencies:
+  ## Required IDF version
+  idf: ">=4.1.0"
+  espressif/esp_modem:
+    version: "^1.0.0"
+    override_path: "../../../"

components/esp_modem/test/target_urc/main/urc_test.cpp

@@ -0,0 +1,158 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include <cstring>
+#include "freertos/FreeRTOS.h"
+#include "freertos/event_groups.h"
+#include "esp_netif.h"
+#include "cxx_include/esp_modem_dte.hpp"
+#include "esp_modem_config.h"
+#include "cxx_include/esp_modem_api.hpp"
+#include "cxx_include/esp_modem_dce_factory.hpp"
+#include "cxx_include/esp_modem_command_library_utils.hpp"
+#include "esp_log.h"
+#include "sdkconfig.h"
+
+static const char *TAG = "urc_test";
+static EventGroupHandle_t s_event_group = nullptr;
+
+class ESP_AT_Module: public ::esp_modem::ModuleIf {
+public:
+    explicit ESP_AT_Module(std::shared_ptr<::esp_modem::DTE> dte, const esp_modem_dce_config *config):
+        dte(std::move(dte)) {}
+
+    bool setup_data_mode() override
+    {
+        // not using network here
+        return true;
+    }
+
+    bool set_mode(::esp_modem::modem_mode mode) override
+    {
+        // we never allow mode change
+        return false;
+    }
+
+protected:
+    std::shared_ptr<::esp_modem::DTE> dte;
+};
+
+class DCE : public esp_modem::DCE_T<ESP_AT_Module> {
+    using DCE_T<ESP_AT_Module>::DCE_T;
+public:
+
+
+    bool init()
+    {
+        for (int i = 0; i < 5; ++i) {
+            if (sync() == esp_modem::command_result::OK) {
+                ESP_LOGI(TAG, "Modem in sync");
+                return true;
+            }
+            vTaskDelay(pdMS_TO_TICKS(500 * (i + 1)));
+        }
+        ESP_LOGE(TAG, "Failed to sync with esp-at");
+        return false;
+    }
+
+    esp_modem::command_result sync()
+    {
+        auto ret = esp_modem::dce_commands::generic_command_common(dte.get(), "AT\r\n");
+        ESP_LOGI(TAG, "Syncing with esp-at...(%d)", static_cast<int>(ret));
+        return ret;
+    }
+
+    bool http_get(const std::string &url)
+    {
+        std::string command = "AT+HTTPCGET=\"" + url + "\"\r\n";
+        set_urc(handle_urc);
+        auto ret = dte->write(esp_modem::DTE_Command(command));
+        ESP_LOGI(TAG, "HTTP GET...(%d)", static_cast<int>(ret));
+        return ret > 0;
+    }
+
+    bool start_http_server() const
+    {
+        auto ret = esp_modem::dce_commands::generic_command_common(dte.get(), "AT+HTTPD\r\n");
+        ESP_LOGI(TAG, "Start HTTP server...(%d)", static_cast<int>(ret));
+        return ret == esp_modem::command_result::OK;
+    }
+
+    static constexpr int transfer_completed = 1;
+private:
+    static esp_modem::command_result handle_urc(uint8_t *data, size_t len)
+    {
+        static int start_chunk = 0;
+        static int end_chunk = 0;
+        std::string_view chunk((const char*)data + start_chunk, len - start_chunk);
+        int newline = chunk.find('\n');
+        if (newline == std::string_view::npos) {
+            end_chunk = len;    // careful, this grows buffer usage
+            printf(".");
+            return esp_modem::command_result::TIMEOUT;
+        }
+        printf("%.*s\n", newline, (char*)data + start_chunk);
+        start_chunk = end_chunk;
+        // check for the last one
+        constexpr char last_chunk[] = "Transfer completed";
+        if (memmem(data, len, last_chunk, sizeof(last_chunk) - 1) != nullptr) {
+            xEventGroupSetBits(s_event_group, transfer_completed);
+        }
+        return esp_modem::command_result::OK;
+    }
+};
+
+class Factory: public ::esp_modem::dce_factory::Factory {
+public:
+    static std::unique_ptr<DCE> create(const esp_modem::dce_config *config, std::shared_ptr<esp_modem::DTE> dte, esp_netif_t *netif)
+    {
+        return build_generic_DCE<ESP_AT_Module, DCE, std::unique_ptr<DCE>>(config, std::move(dte), netif);
+    }
+};
+
+std::unique_ptr<DCE> create(std::shared_ptr<esp_modem::DTE> dte)
+{
+    esp_netif_config_t netif_ppp_config = ESP_NETIF_DEFAULT_PPP();
+    static esp_netif_t *netif = esp_netif_new(&netif_ppp_config);
+    assert(netif);
+
+    esp_modem_dce_config_t dce_config = ESP_MODEM_DCE_DEFAULT_CONFIG("APN"); // dummy config (not used with esp-at)
+    return Factory::create(&dce_config, std::move(dte), netif);
+}
+
+extern "C" void app_main(void)
+{
+    /* Init and register system/core components */
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+    s_event_group = xEventGroupCreate();
+
+    esp_modem_dte_config_t dte_config = ESP_MODEM_DTE_DEFAULT_CONFIG();
+    dte_config.dte_buffer_size = 1024;
+    dte_config.uart_config.tx_io_num = 18;
+    dte_config.uart_config.rx_io_num = 17;
+    auto uart_dte = esp_modem::create_uart_dte(&dte_config);
+    if (uart_dte == nullptr) {
+        ESP_LOGE(TAG, "Failed to create UART DTE");
+        return;
+    }
+    auto dce = create(std::move(uart_dte));
+    if (!dce->init()) {
+        ESP_LOGE(TAG,  "Failed to setup network");
+        return;
+    }
+
+    dce->start_http_server();
+
+    dce->http_get("http://127.0.0.1:8080/async");
+
+    EventBits_t bits = xEventGroupWaitBits(s_event_group, 1, pdTRUE, pdFALSE, pdMS_TO_TICKS(15000));
+    if (bits & DCE::transfer_completed) {
+        ESP_LOGI(TAG, "Request finished!");
+    }
+    dce->sync();
+    vEventGroupDelete(s_event_group);
+    ESP_LOGI(TAG, "Done");
+}

components/esp_modem/test/target_urc/sdkconfig.defaults

@@ -0,0 +1,3 @@
+CONFIG_COMPILER_CXX_EXCEPTIONS=y
+CONFIG_LWIP_PPP_SUPPORT=y
+CONFIG_ESP_MODEM_URC_HANDLER=y

components/esp_websocket_client/.cz.yaml

@@ -3,6 +3,6 @@ commitizen:
   bump_message: 'bump(websocket): $current_version -> $new_version'
   pre_bump_hooks: python ../../ci/changelog.py esp_websocket_client
   tag_format: websocket-v$version
-  version: 1.4.0
+  version: 1.5.0
   version_files:
   - idf_component.yml

components/esp_websocket_client/CHANGELOG.md

@@ -1,5 +1,17 @@
 # Changelog
 
+## [1.5.0](https://github.com/espressif/esp-protocols/commits/websocket-v1.5.0)
+
+### Features
+
+- add separate tx lock for send and receive ([250eebf](https://github.com/espressif/esp-protocols/commit/250eebf))
+- add unregister event to websocket client ([ce16050](https://github.com/espressif/esp-protocols/commit/ce16050))
+- add ability to reconnect after close ([19891d8](https://github.com/espressif/esp-protocols/commit/19891d8))
+
+### Bug Fixes
+
+- release client-lock during WEBSOCKET_EVENT_DATA ([030cb75](https://github.com/espressif/esp-protocols/commit/030cb75))
+
 ## [1.4.0](https://github.com/espressif/esp-protocols/commits/websocket-v1.4.0)
 
 ### Features

components/esp_websocket_client/Kconfig

@@ -7,4 +7,17 @@ menu "ESP WebSocket client"
             Enable this option will reallocated buffer when send or receive data and free them when end of use.
             This can save about 2 KB memory when no websocket data send and receive.
 
+    config ESP_WS_CLIENT_SEPARATE_TX_LOCK
+        bool "Enable separate tx lock for send and receive data"
+        default n
+        help
+            Enable this option will use separate lock for send and receive data.
+            This can avoid the lock contention when send and receive data at the same time.
+
+    config ESP_WS_CLIENT_TX_LOCK_TIMEOUT_MS
+        int "TX lock timeout in milliseconds"
+        depends on ESP_WS_CLIENT_SEPARATE_TX_LOCK
+        default 2000
+        help
+            Timeout for acquiring the TX lock when using separate TX lock.
 endmenu

components/esp_websocket_client/esp_websocket_client.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2015-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -39,6 +39,10 @@ static const char *TAG = "websocket_client";
 #define WEBSOCKET_KEEP_ALIVE_INTERVAL   (5)
 #define WEBSOCKET_KEEP_ALIVE_COUNT      (3)
 
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+#define WEBSOCKET_TX_LOCK_TIMEOUT_MS    (CONFIG_ESP_WS_CLIENT_TX_LOCK_TIMEOUT_MS)
+#endif
+
 #define ESP_WS_CLIENT_MEM_CHECK(TAG, a, action) if (!(a)) {                                         \
         ESP_LOGE(TAG,"%s(%d): %s", __FUNCTION__, __LINE__, "Memory exhausted");                     \
         action;                                                                                     \
@@ -80,6 +84,7 @@ typedef struct {
     char                        *auth;
     int                         port;
     bool                        auto_reconnect;
+    bool                        close_reconnect;
     void                        *user_context;
     int                         network_timeout_ms;
     char                        *subprotocol;
@@ -130,6 +135,9 @@ struct esp_websocket_client {
     bool                        selected_for_destroying;
     EventGroupHandle_t          status_bits;
     SemaphoreHandle_t           lock;
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+    SemaphoreHandle_t           tx_lock;
+#endif
     size_t                      errormsg_size;
     char                        *errormsg_buffer;
     char                        *rx_buffer;
@@ -376,6 +384,7 @@ static esp_err_t esp_websocket_client_set_config(esp_websocket_client_handle_t c
     if (config->disable_auto_reconnect) {
         cfg->auto_reconnect = false;
     }
+    cfg->close_reconnect = config->enable_close_reconnect;
 
     if (config->disable_pingpong_discon) {
         cfg->pingpong_timeout_sec = 0;
@@ -439,6 +448,9 @@ static void destroy_and_free_resources(esp_websocket_client_handle_t client)
         esp_transport_list_destroy(client->transport_list);
     }
     vSemaphoreDelete(client->lock);
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+    vSemaphoreDelete(client->tx_lock);
+#endif
     free(client->tx_buffer);
     free(client->rx_buffer);
     free(client->errormsg_buffer);
@@ -608,10 +620,17 @@ static int esp_websocket_client_send_with_exact_opcode(esp_websocket_client_hand
         return -1;
     }
 
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+    if (xSemaphoreTakeRecursive(client->tx_lock, timeout) != pdPASS) {
+        ESP_LOGE(TAG, "Could not lock ws-client within %" PRIu32 " timeout", timeout);
+        return -1;
+    }
+#else
     if (xSemaphoreTakeRecursive(client->lock, timeout) != pdPASS) {
         ESP_LOGE(TAG, "Could not lock ws-client within %" PRIu32 " timeout", timeout);
         return -1;
     }
+#endif
 
     if (esp_websocket_new_buf(client, true) != ESP_OK) {
         ESP_LOGE(TAG, "Failed to setup tx buffer");
@@ -651,7 +670,11 @@ static int esp_websocket_client_send_with_exact_opcode(esp_websocket_client_hand
     ret = widx;
 
 unlock_and_return:
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+    xSemaphoreGiveRecursive(client->tx_lock);
+#else
     xSemaphoreGiveRecursive(client->lock);
+#endif
     return ret;
 }
 
@@ -687,6 +710,11 @@ esp_websocket_client_handle_t esp_websocket_client_init(const esp_websocket_clie
     client->lock = xSemaphoreCreateRecursiveMutex();
     ESP_WS_CLIENT_MEM_CHECK(TAG, client->lock, goto _websocket_init_fail);
 
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+    client->tx_lock = xSemaphoreCreateRecursiveMutex();
+    ESP_WS_CLIENT_MEM_CHECK(TAG, client->tx_lock, goto _websocket_init_fail);
+#endif
+
     client->config = calloc(1, sizeof(websocket_config_storage_t));
     ESP_WS_CLIENT_MEM_CHECK(TAG, client->config, goto _websocket_init_fail);
 
@@ -965,8 +993,17 @@ static esp_err_t esp_websocket_client_recv(esp_websocket_client_handle_t client)
     if (client->last_opcode == WS_TRANSPORT_OPCODES_PING) {
         const char *data = (client->payload_len == 0) ? NULL : client->rx_buffer;
         ESP_LOGD(TAG, "Sending PONG with payload len=%d", client->payload_len);
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+        if (xSemaphoreTakeRecursive(client->tx_lock, WEBSOCKET_TX_LOCK_TIMEOUT_MS) != pdPASS) {
+            ESP_LOGE(TAG, "Could not lock ws-client within %d timeout", WEBSOCKET_TX_LOCK_TIMEOUT_MS);
+            return ESP_FAIL;
+        }
+#endif
         esp_transport_ws_send_raw(client->transport, WS_TRANSPORT_OPCODES_PONG | WS_TRANSPORT_OPCODES_FIN, data, client->payload_len,
                                   client->config->network_timeout_ms);
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+        xSemaphoreGiveRecursive(client->tx_lock);
+#endif
     } else if (client->last_opcode == WS_TRANSPORT_OPCODES_PONG) {
         client->wait_for_pong_resp = false;
     } else if (client->last_opcode == WS_TRANSPORT_OPCODES_CLOSE) {
@@ -1048,8 +1085,16 @@ static void esp_websocket_client_task(void *pv)
                 if (_tick_get_ms() - client->ping_tick_ms > client->config->ping_interval_sec * 1000) {
                     client->ping_tick_ms = _tick_get_ms();
                     ESP_LOGD(TAG, "Sending PING...");
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+                    if (xSemaphoreTakeRecursive(client->tx_lock, WEBSOCKET_TX_LOCK_TIMEOUT_MS) != pdPASS) {
+                        ESP_LOGE(TAG, "Could not lock ws-client within %d timeout", WEBSOCKET_TX_LOCK_TIMEOUT_MS);
+                        break;
+                    }
+#endif
                     esp_transport_ws_send_raw(client->transport, WS_TRANSPORT_OPCODES_PING | WS_TRANSPORT_OPCODES_FIN, NULL, 0, client->config->network_timeout_ms);
-
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+                    xSemaphoreGiveRecursive(client->tx_lock);
+#endif
                     if (!client->wait_for_pong_resp && client->config->pingpong_timeout_sec) {
                         client->pingpong_tick_ms = _tick_get_ms();
                         client->wait_for_pong_resp = true;
@@ -1084,7 +1129,16 @@ static void esp_websocket_client_task(void *pv)
             // if closing not initiated by the client echo the close message back
             if ((CLOSE_FRAME_SENT_BIT & xEventGroupGetBits(client->status_bits)) == 0) {
                 ESP_LOGD(TAG, "Closing initiated by the server, sending close frame");
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+                if (xSemaphoreTakeRecursive(client->tx_lock, WEBSOCKET_TX_LOCK_TIMEOUT_MS) != pdPASS) {
+                    ESP_LOGE(TAG, "Could not lock ws-client within %d timeout", WEBSOCKET_TX_LOCK_TIMEOUT_MS);
+                    break;
+                }
+#endif
                 esp_transport_ws_send_raw(client->transport, WS_TRANSPORT_OPCODES_CLOSE | WS_TRANSPORT_OPCODES_FIN, NULL, 0, client->config->network_timeout_ms);
+#ifdef CONFIG_ESP_WS_CLIENT_SEPARATE_TX_LOCK
+                xSemaphoreGiveRecursive(client->tx_lock);
+#endif
                 xEventGroupSetBits(client->status_bits, CLOSE_FRAME_SENT_BIT);
             }
             break;
@@ -1128,10 +1182,21 @@ static void esp_websocket_client_task(void *pv)
             } else if (ret < 0) {
                 ESP_LOGW(TAG, "Connection terminated while waiting for clean TCP close");
             }
-            client->run = false;
-            client->state = WEBSOCKET_STATE_UNKNOW;
-            esp_websocket_client_dispatch_event(client, WEBSOCKET_EVENT_CLOSED, NULL, 0);
-            break;
+            if (client->config->close_reconnect && xSemaphoreTakeRecursive(client->lock, lock_timeout) == pdPASS) {
+                client->state = WEBSOCKET_STATE_WAIT_TIMEOUT;
+                client->error_handle.error_type = WEBSOCKET_ERROR_TYPE_SERVER_CLOSE;
+                esp_transport_close(client->transport);
+                esp_websocket_client_dispatch_event(client, WEBSOCKET_EVENT_CLOSED, NULL, 0);
+                client->reconnect_tick_ms = _tick_get_ms();
+                ESP_LOGI(TAG, "Reconnect after %d ms", client->wait_timeout_ms);
+                xEventGroupClearBits(client->status_bits, STOPPED_BIT | CLOSE_FRAME_SENT_BIT);
+                xSemaphoreGiveRecursive(client->lock);
+            } else {
+                client->run = false;
+                client->state = WEBSOCKET_STATE_UNKNOW;
+                esp_websocket_client_dispatch_event(client, WEBSOCKET_EVENT_CLOSED, NULL, 0);
+                break;
+            }
         }
     }
 

components/esp_websocket_client/idf_component.yml

@@ -1,4 +1,4 @@
-version: "1.4.0"
+version: "1.5.0"
 description: WebSocket protocol client for ESP-IDF
 url: https://github.com/espressif/esp-protocols/tree/master/components/esp_websocket_client
 dependencies:

components/esp_websocket_client/include/esp_websocket_client.h

@@ -48,7 +48,8 @@ typedef enum {
     WEBSOCKET_ERROR_TYPE_NONE = 0,
     WEBSOCKET_ERROR_TYPE_TCP_TRANSPORT,
     WEBSOCKET_ERROR_TYPE_PONG_TIMEOUT,
-    WEBSOCKET_ERROR_TYPE_HANDSHAKE
+    WEBSOCKET_ERROR_TYPE_HANDSHAKE,
+    WEBSOCKET_ERROR_TYPE_SERVER_CLOSE
 } esp_websocket_error_type_t;
 
 /**
@@ -101,6 +102,7 @@ typedef struct {
     const char                  *password;                  /*!< Using for Http authentication */
     const char                  *path;                      /*!< HTTP Path, if not set, default is `/` */
     bool                        disable_auto_reconnect;     /*!< Disable the automatic reconnect function when disconnected */
+    bool                        enable_close_reconnect;     /*!< Enable reconnect after server close */
     void                        *user_context;              /*!< HTTP user data context */
     int                         task_prio;                  /*!< Websocket task priority */
     const char                 *task_name;                  /*!< Websocket task name */

components/mosquitto/.cz.yaml

@@ -3,6 +3,6 @@ commitizen:
   bump_message: 'bump(mosq): $current_version -> $new_version'
   pre_bump_hooks: python ../../ci/changelog.py mosquitto
   tag_format: mosq-v$version
-  version: 2.0.20~2
+  version: 2.0.20~3
   version_files:
   - idf_component.yml

components/mosquitto/CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## [2.0.20~3](https://github.com/espressif/esp-protocols/commits/mosq-v2.0.20_3)
+
+
+### Bug Fixes
+
+- Support build on older IDF branches ([13b90ad1](https://github.com/espressif/esp-protocols/commit/13b90ad1))
+- Fix misleading error when accepting connection ([fd410061](https://github.com/espressif/esp-protocols/commit/fd410061), [#807](https://github.com/espressif/esp-protocols/issues/807))
+- Make mosquitto component c++ compatible ([c4169765](https://github.com/espressif/esp-protocols/commit/c4169765), [#817](https://github.com/espressif/esp-protocols/issues/817))
+- include config.h before any system header ([1b1ede43](https://github.com/espressif/esp-protocols/commit/1b1ede43))
+
 ## [2.0.20~2](https://github.com/espressif/esp-protocols/commits/mosq-v2.0.20_2)
 
 ### Features

components/mosquitto/Kconfig

@@ -1,5 +1,13 @@
 menu "Mosquitto"
 
+    config MOSQ_IS_ENABLED
+        # Invisible option that is enabled if MOSQ is added to the IDF components.
+        # This is used to "select" CONFIG_ESP_TLS_SERVER option (needed for TLS connection)
+        # (these are optionally used in mosq)
+        bool
+        default "y"
+        select ESP_TLS_SERVER
+
     config MOSQ_ENABLE_SYS
         bool "Enable $SYS topics"
         default n

components/mosquitto/api.md

@@ -37,7 +37,7 @@ Variables:
 
 -  void(\* handle_message_cb  <br>On message callback. If configured, user function is called whenever mosquitto processes a message.
 
--  char \* host  <br>Address on which the broker is listening for connections
+-  const char \* host  <br>Address on which the broker is listening for connections
 
 -  int port  <br>Port number of the broker to listen to
 

components/mosquitto/examples/serverless_mqtt/CMakeLists.txt

@@ -3,4 +3,21 @@
 cmake_minimum_required(VERSION 3.16)
 
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+
+# Setup ESP-PEER from GitHub repo (but it's supported only on certain targets)
+set(ESP_PEER_COMPATIBLE_TARGETS "esp32s2" "esp32s3" "esp32p4" "esp32")
+if(IDF_TARGET IN_LIST ESP_PEER_COMPATIBLE_TARGETS)
+execute_process(COMMAND ${CMAKE_BINARY_DIR}/../esp_peer_setup/install.sh
+                ${CMAKE_BINARY_DIR}
+                WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
+                RESULT_VARIABLE script_result)
+
+if(script_result)
+    message(FATAL_ERROR "Script esp_peer_setup.sh failed with exit code ${script_result}")
+endif()
+list(APPEND EXTRA_COMPONENT_DIRS "${CMAKE_BINARY_DIR}/esp-peer/components/")
+else()
+    message(STATUS "ESP-PEER is not compatible with this target")
+endif()
+
 project(serverless_mqtt)

components/mosquitto/examples/serverless_mqtt/README.md

@@ -3,14 +3,19 @@
 MQTT served by (two) mosquitto's running on two ESP chips.
 
 * Leverages MQTT connectivity between two private networks without cloud premisses.
-* Creates two local MQTT servers (on ESP32x's) which are being synchronized over peer to peer connection (established via ICE protocol, by [libjuice](https://github.com/paullouisageneau/libjuice)).
+* Creates two local MQTT servers (on ESP32x's) which are being synchronized over peer to peer connection (established via ICE/WebRTC protocol)
+
+## Peer to peer connection
+
+Could be established either by [libjuice](https://github.com/paullouisageneau/libjuice) or [esp-webRTC](https://github.com/espressif/esp-webrtc-solution). While `juice` is just a low level implementation of ICE-UDP, we need to provide some signalling and synchronization, the `WebRTC` is full-fledged solution to establish a peer connection using standardized signalling, security and transfer protocols.
+
 
 ## How it works
 
 This example needs two ESP32 chipsets, that will create two separate Wi-Fi networks (IoT networks) used for IoT devices.
 Each IoT network is served by an MQTT server (using mosquitto component).
 This example will also synchronize these two MQTT brokers, as if there was only one IoT network with one broker.
-This example creates a peer to peer connection between two chipsets to keep them synchronize. This connection utilizes libjuice (which implements a simplified ICE-UDP) to traverse NATs, which enabling direct connection between two private networks behind NATs.
+This example creates a peer to peer connection between two chipsets to keep them synchronize. This connection utilizes libjuice (which implements a simplified ICE-UDP) or esp-webRTC (which implements WebRTC) to traverse NATs, which enabling direct connection between two private networks behind NATs.
 
 * Diagram
 
@@ -19,12 +24,16 @@ This example creates a peer to peer connection between two chipsets to keep them
 Here's a step-by-step procedure of establishing this remote connection:
 1) Initialize and start Wi-Fi AP (for IoT networks) and Wi-Fi station (for internet connection)
 2) Start mosquitto broker on IoT network
-3) Start libjuice to gather connection candidates
-4) Synchronize using a public MQTT broker and exchange ICE descriptors
-5) Establish ICE UDP connection between the two ESP32 chipsets
+3) Start peer to peer connection
+  - In case of `libjuice`
+      - gather connection candidates
+      - synchronize using a public MQTT broker and exchange ICE descriptors
+      - establish ICE UDP connection between the two ESP32 chipsets
+  - In case of `webRTC` simply start the connection.
 6) Start forwarding mqtt messages
    - Each remote datagram (received from ICE-UDP channel) is re-published to the local MQTT server
-   - Each local MQTT message (received from mosquitto on_message callback) is sent in ICE-UDP datagram
+   - Each local MQTT message (received from mosquitto on_message callback) is sent in a peer message
+
 
 ## How to use this example
 
@@ -33,7 +42,9 @@ You need two ESP32 devices that support Wi-Fi station and Wi-Fi software access
 * Configure Wi-Fi credentials for both devices on both interfaces
   * These devices would be deployed in distinct Wi-Fi environments, so the Wi-Fi station credentials would likely be different.
   * They also create their own IoT network (on the soft-AP interface) Wi-Fi, so the AP credentials would likely be the same, suggesting the IoT networks will be keep synchronized (even though these are two distict Wi-Fi networks).
-* Choose `CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1` for one device and `CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER2` for another. It's not important which device is PEER1, since the code is symmetric, but these two devices need to have different role.
+* Choose the peer library
+* Only for `libjuice`:
+  - Choose `CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1` for one device and `CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER2` for another. It's not important which device is PEER1, since the code is symmetric, but these two devices need to have different role.
 * Optionally: You can use `idf.py` `-D` and `-B` flag to keep separate build directories and sdkconfigs for these two roles
 ```
 idf.py -B build1 -DSDKCONFIG=build1/sdkconfig menuconfig build flash monitor
@@ -44,9 +55,129 @@ idf.py -B build1 -DSDKCONFIG=build1/sdkconfig menuconfig build flash monitor
   * Join PEER2 device's AP and connect to the MQTT broker with one or more clients, subscribing to one or more topics.
   * Whenever you publish to a topic, all subscribed clients should receive the message, no matter which Wi-Fi network they're connected to.
 
+## Example output
+
+## With libjuice
+
+```
+I (4746) esp_netif_handlers: sta ip: 192.168.0.40, mask: 255.255.255.0, gw: 192.168.0.1
+4: mosquitto version v2.0.20~3 starting
+4: Using default config.
+4: Opening ipv4 listen socket on port 1883.
+4: mosquitto version v2.0.20~3 running
+I (4756) serverless_mqtt1: desc: a=ice-ufrag:sGdl
+a=ice-pwd:R4IPGsFctITbT1dCZbfQTL
+a=ice-options:ice2,trickle
+
+00:00:04 INFO    agent.c:1100: Changing state to gathering
+I (4776) serverless_mqtt1: JUICE state change: gathering
+00:00:04 INFO    agent.c:1100: Changing state to connecting
+I (4786) serverless_mqtt1: JUICE state change: connecting
+00:00:04 INFO    agent.c:422: Using STUN server stun.l.google.com:19302
+00:00:04 INFO    agent.c:1378: STUN server binding successful
+00:00:04 INFO    agent.c:1397: Got STUN mapped address 185.194.44.31:62703 from server
+00:00:04 INFO    agent.c:2428: Candidate gathering done
+I (5066) serverless_mqtt1: Gathering done
+I (5066) serverless_mqtt1: desc: {
+        "desc": "a=ice-ufrag:sGdl\r\na=ice-pwd:R4IPGsFctITbT1dCZbfQTL\r\na=ice-options:ice2,trickle\r\n",
+        "cand0":        "a=candidate:1 1 UDP 2122317823 192.168.0.40 62703 typ host",
+        "cand1":        "a=candidate:2 1 UDP 1686109951 185.194.44.31 62703 typ srflx raddr 0.0.0.0 rport 0"
+}
+I (5096) serverless_mqtt1: Other event id:7
+```
+
+### With esp-peer
+
+```
+I (5992) esp_netif_handlers: sta ip: 192.168.0.42, mask: 255.255.255.0, gw: 192.168.0.1
+4: mosquitto version v2.0.20~3 starting
+4: Using default config.
+4: Opening ipv4 listen socket on port 1883.
+4: mosquitto version v2.0.20~3 running
+I (6702) esp-x509-crt-bundle: Certificate validated
+I (7982) APPRTC_SIG: result SUCCESS
+Initials set to 1
+I (7982) HTTPS_CLIENT: HTTP POST Status = 200, content_length = 911
+I (8652) esp-x509-crt-bundle: Certificate validated
+Got url:stun:webrtc.espressif.com:3478 user_name: 1752835118:ninefingers psw:/a8EMa7VBKpFa1I4Rdpv561YDPw=
+I (10022) HTTPS_CLIENT: HTTP POST Status = 200, content_length = 173
+I (10032) serverless_mqtt_webrtc: Signaling ice info handler 0x0
+I (10042) DTLS: Init SRTP OK
+I (11512) DTLS_SRTP: dtls_srtp init done
+I (11522) APPRTC_SIG: Registering signaling channel.
+I (11522) APPRTC_SIG: Connecting to wss://webrtc.espressif.com:8089/ws...
+I (11532) websocket_client: Started
+I (11532) serverless_mqtt_webrtc: Waiting for peer to connect
+I (12122) esp-x509-crt-bundle: Certificate validated
+I (13502) APPRTC_SIG: WEBSOCKET_EVENT_CONNECTED
+I (13502) APPRTC_SIG: send to remote : {"cmd":"register","roomid":"111116","clientid":"93827452"}
+I (13502) serverless_mqtt_webrtc: Peer state: 2
+I (13522) AGENT: Start agent as Controlling
+I (13522) PEER_DEF: Start DTLS role as 1
+I (13522) AGENT: Send STUN binding request
+I (13522) AGENT: Send allocate now
+Got error code 401
+I (13802) AGENT: Send allocate now
+I (14112) AGENT: 0 Get candidate success user:1752835118:ninefingers psw:/a8EMa7VBKpFa1I4Rdpv561YDPw=
+I (14112) APPRTC_SIG: Begin to send offer to https://webrtc.espressif.com/message/111116/93827452
+I (14782) esp-x509-crt-bundle: Certificate validated
+I (16472) HTTPS_CLIENT: HTTP POST Status = 200, content_length = 21
+I (21602) PEER_DEF: A SRC: 4
+I (21602) PEER_DEF: Get peer role 0
+I (21602) PEER_DEF: Get peer role 0
+I (21602) AGENT: 0 Add remote type:2 185.194.44.31:60872
+I (21612) AGENT: 0 Add remote type:4 172.31.6.33:59012
+I (21612) AGENT: 0 Add remote type:1 192.168.0.41:60872
+0 Sorted pair 0 type: 1 local:192.168.0.42:63459 Remote:192.168.0.41:60872
+0 Sorted pair 1 type: 2 local:185.194.44.31:63459 Remote:185.194.44.31:60872
+0 Sorted pair 2 type: 4 local:172.31.6.33:59013 Remote:172.31.6.33:59012
+I (21642) serverless_mqtt_webrtc: Peer state: 3
+I (22002) AGENT: 0 Send binding request (cand:0) local:192.168.0.42:63459 remote:192.168.0.41:60872 id:76e5004e797d87a62756c714
+I (22002) AGENT: 0 Send binding request (cand:0) local:185.194.44.31:63459 remote:185.194.44.31:60872 id:4c598d93643bd7252b449456
+I (22012) AGENT: 0 Send binding request (cand:0) local:172.31.6.33:59013 remote:172.31.6.33:59012 id:6db505597d157d8d71dfed43
+I (22022) AGENT: 0 send indication bind request
+
+I (22202) AGENT: 0 PeerBinding recv local:192.168.0.42:63459 remote:192.168.0.41:60872
+I (22202) AGENT: 0 Send binding response local:192.168.0.42:63459 remote:192.168.0.41:60872
+I (22212) AGENT: 0 Select pair192.168.0.41:60872
+I (22212) AGENT: 0 Send binding request (cand:1) local:192.168.0.42:63459 remote:192.168.0.41:60872 id:45cb977b6ea3bbbe3a984b90
+I (22222) AGENT: 0 PeerIndication recv local:172.31.6.33:59013 remote:172.31.6.33:59012
+I (22402) AGENT: 0 PeerBinding recv local:192.168.0.42:63459 remote:192.168.0.41:60872
+I (22402) AGENT: 0 Send binding response local:192.168.0.42:63459 remote:192.168.0.41:60872
+I (22412) AGENT: 0 Candidate responsed
+I (22412) AGENT: 0 PeerBinding recv local:192.168.0.42:63459 remote:192.168.0.41:60872
+I (22422) AGENT: 0 Connection OK 192.168.0.41:60872
+I (22422) serverless_mqtt_webrtc: Peer state: 5
+I (22452) DTLS: Start to do server handshake
+
+Works as 1
+I (23842) DTLS: SRTP connected OK
+I (23852) DTLS: Server handshake success
+I (23852) PEER_DEF: DTLS handshake success
+I (23852) serverless_mqtt_webrtc: Peer state: 6
+I (23852) serverless_mqtt_webrtc: Peer is connected!
+I (23862) serverless_mqtt: local client event id:7
+22: New connection from 192.168.4.1:63904 on port 1883.
+22: New client connected from 192.168.4.1:63904 as local_mqtt (p2, c1, k120).
+I (23892) serverless_mqtt: local client connected
+I (23872) serverless_mqtt: Everything is ready, exiting main task
+I (23892) main_task: Returned from app_main()
+I (24552) SCTP: 0 Receive chunk 1 SCTP_INIT
+I (24552) SCTP: 0 state 2
+I (24552) SCTP: Send INIT_ACK chunk
+I (24762) SCTP: 0 Receive chunk 10 SCTP_COOKIE_ECHO
+I (24762) SCTP: Send ECHO_ACK chunk
+I (24762) SCTP: 0 state 5
+I (24762) serverless_mqtt_webrtc: Peer state: 8
+I (24762) SCTP: 0 Receive chunk 10 SCTP_COOKIE_ECHO
+I (24772) SCTP: Send ECHO_ACK chunk
+I (24962) SCTP: Get DCEP esp_channel event:3 type:0 si:2
+I (24972) serverless_mqtt_webrtc: Peer state: 9
+```
+
 ## Warning
 
-This example uses libjuice as a dependency:
+This example uses `libjuice` as a dependency:
 
 * libjuice (UDP Interactive Connectivity Establishment): https://github.com/paullouisageneau/libjuice
 

components/mosquitto/examples/serverless_mqtt/esp_peer_setup/Remove-deprecated-freeRTOS-header.patch

@@ -0,0 +1,28 @@
+From cdc43a56f5ea1ab1935f55f47f8644f5dd30825e Mon Sep 17 00:00:00 2001
+From: David Cermak <cermak@espressif.com>
+Date: Thu, 10 Jul 2025 11:09:57 +0200
+Subject: [PATCH] fix(media_lib): Remove deprecated freeRTOS header
+
+---
+ components/media_lib_sal/port/media_lib_os_freertos.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/components/media_lib_sal/port/media_lib_os_freertos.c b/components/media_lib_sal/port/media_lib_os_freertos.c
+index d248d59..aea0527 100644
+--- a/components/media_lib_sal/port/media_lib_os_freertos.c
++++ b/components/media_lib_sal/port/media_lib_os_freertos.c
+@@ -40,8 +40,12 @@
+ #include "esp_idf_version.h"
+
+ #if CONFIG_FREERTOS_ENABLE_TASK_SNAPSHOT
++#if (ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 2, 0))
++#include "esp_private/freertos_debug.h"
++#else
+ #include "freertos/task_snapshot.h"
+ #endif
++#endif
+
+ #ifdef __XTENSA__
+ #include "esp_debug_helpers.h"
+--
+2.43.0

components/mosquitto/examples/serverless_mqtt/esp_peer_setup/install.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+set -e
+echo "bin_dir: $1"
+
+bin_dir="$1"
+THIS_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+ESP_PEER_VERSION="ccff3bd65cea750bf6c0abcf9d95b931ba9329f0"
+
+ESP_PEER_URL="https://github.com/espressif/esp-webrtc-solution/archive/${ESP_PEER_VERSION}.zip"
+ESP_PEER_DIR="${bin_dir}/esp-peer"
+ZIP_PATH="${bin_dir}/esp-peer.zip"
+EXTRACTED_DIR="${ESP_PEER_DIR}/esp-webrtc-solution-${ESP_PEER_VERSION}"
+COMPONENTS_SRC="${EXTRACTED_DIR}/components"
+COMPONENTS_DST="${ESP_PEER_DIR}/components"
+PATCH_FILE_1="${THIS_DIR}/Remove-deprecated-freeRTOS-header.patch"
+PATCH_FILE_2="${THIS_DIR}/libpeer-Add-direct-dependency-to-libsrtp.patch"
+
+# Download if not exists
+if [ ! -d "$EXTRACTED_DIR" ]; then
+    echo "Downloading esp-peer ${ESP_PEER_VERSION}..."
+    wget -O "$ZIP_PATH" "$ESP_PEER_URL"
+    unzip -o "$ZIP_PATH" -d "$ESP_PEER_DIR"
+    patch -p1 -d "$EXTRACTED_DIR" < "$PATCH_FILE_1"
+    patch -p1 -d "$EXTRACTED_DIR" < "$PATCH_FILE_2"
+    mv ${EXTRACTED_DIR}/components ${ESP_PEER_DIR}
+    mv ${ESP_PEER_DIR}/components/esp_webrtc/impl/peer_default ${ESP_PEER_DIR}/components
+fi

components/mosquitto/examples/serverless_mqtt/esp_peer_setup/libpeer-Add-direct-dependency-to-libsrtp.patch

@@ -0,0 +1,23 @@
+From 695e057000698f4897b6c5802851499842e2fe31 Mon Sep 17 00:00:00 2001
+From: David Cermak <cermak@espressif.com>
+Date: Fri, 11 Jul 2025 16:59:21 +0200
+Subject: [PATCH] fix(libpeer): Add direct dependency to libsrtp
+
+---
+ components/esp_webrtc/impl/peer_default/CMakeLists.txt | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/components/esp_webrtc/impl/peer_default/CMakeLists.txt b/components/esp_webrtc/impl/peer_default/CMakeLists.txt
+index 2af35cf..3fb4615 100644
+--- a/components/esp_webrtc/impl/peer_default/CMakeLists.txt
++++ b/components/esp_webrtc/impl/peer_default/CMakeLists.txt
+@@ -2,6 +2,6 @@ idf_component_register(INCLUDE_DIRS ./include)
+
+ get_filename_component(BASE_DIR ${CMAKE_CURRENT_SOURCE_DIR} NAME)
+ add_prebuilt_library(${BASE_DIR} "${CMAKE_CURRENT_SOURCE_DIR}/libs/${IDF_TARGET}/libpeer_default.a"
+-                     PRIV_REQUIRES ${BASE_DIR} esp_timer)
++                     PRIV_REQUIRES ${BASE_DIR} esp_timer espressif__esp_libsrtp)
+ target_link_libraries(${COMPONENT_LIB}  INTERFACE "-L ${CMAKE_CURRENT_SOURCE_DIR}/libs/${IDF_TARGET}")
+ target_link_libraries(${COMPONENT_LIB}  INTERFACE peer_default)
+--
+2.43.0

components/mosquitto/examples/serverless_mqtt/main/CMakeLists.txt

@@ -1,4 +1,14 @@
+if(CONFIG_EXAMPLE_PEER_LIB_ESP_PEER)
+    set(PEER_BACKEND_SRC "peer_impl_webrtc.c")
+else()
+    set(PEER_BACKEND_SRC "peer_impl_juice.c")
+endif()
+
 idf_component_register(SRCS "serverless_mqtt.c"
                             "wifi_connect.c"
+                            "${PEER_BACKEND_SRC}"
                     INCLUDE_DIRS "."
                     REQUIRES libjuice nvs_flash mqtt json esp_wifi)
+if(CONFIG_EXAMPLE_PEER_LIB_ESP_PEER)
+    idf_component_optional_requires(PUBLIC media_lib_sal esp_webrtc peer_default)
+endif()

components/mosquitto/examples/serverless_mqtt/main/Kconfig.projbuild

@@ -33,8 +33,40 @@ menu "Example Configuration"
                 WiFi station password for the example to use.
     endmenu
 
+    choice EXAMPLE_PEER_LIB
+        prompt "Choose peer library"
+        default EXAMPLE_PEER_LIB_LIBJUICE
+        help
+            Choose the peer library to use for WebRTC communication.
+            libjuice: Use libjuice library for ICE/STUN/TURN (Performs manual signalling)
+            esp_peer: Use ESP-IDF specific peer library
+
+        config EXAMPLE_PEER_LIB_ESP_PEER
+            bool "esp_peer"
+
+        config EXAMPLE_PEER_LIB_LIBJUICE
+            bool "libjuice"
+    endchoice
+
+    config EXAMPLE_WEBRTC_URL
+        string "WebRTC server URL"
+        depends on EXAMPLE_PEER_LIB_ESP_PEER
+        default "https://webrtc.espressif.com/join/"
+        help
+            URL of WebRTC remote endpoint.
+
+    config EXAMPLE_WEBRTC_ROOM_ID
+        string "WebRTC room ID"
+        depends on EXAMPLE_PEER_LIB_ESP_PEER
+        default "12345"
+        help
+            Room ID for WebRTC synchronisation.
+            Could be a random number, but the same for both peers.
+
+
     config EXAMPLE_MQTT_BROKER_URI
         string "MQTT Broker URL"
+        depends on EXAMPLE_PEER_LIB_LIBJUICE
         default "mqtt://mqtt.eclipseprojects.io"
         help
             URL of the mqtt broker use for synchronisation and exchanging
@@ -42,12 +74,14 @@ menu "Example Configuration"
 
     config EXAMPLE_MQTT_SYNC_TOPIC
         string "MQTT topic for synchronisation"
+        depends on EXAMPLE_PEER_LIB_LIBJUICE
         default "/topic/serverless_mqtt"
         help
             MQTT topic used fo synchronisation.
 
     config EXAMPLE_STUN_SERVER
         string "Hostname of STUN server"
+        depends on EXAMPLE_PEER_LIB_LIBJUICE
         default "stun.l.google.com"
         help
             STUN server hostname.
@@ -67,6 +101,7 @@ menu "Example Configuration"
 
     choice EXAMPLE_SERVERLESS_ROLE
         prompt "Choose your role"
+        depends on EXAMPLE_PEER_LIB_LIBJUICE
         default EXAMPLE_SERVERLESS_ROLE_PEER1
         help
             Choose either peer1 or peer2.

components/mosquitto/examples/serverless_mqtt/main/peer_impl.h

@@ -0,0 +1,18 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+
+#include <stdio.h>
+#include "esp_random.h"
+#include "esp_sleep.h"
+#include "mosq_broker.h"
+
+typedef void (*on_peer_recv_t)(const char *data, size_t size);
+
+esp_err_t peer_init(on_peer_recv_t cb);
+
+void peer_get_buffer(char ** buffer, size_t *buffer_len);
+
+void peer_send(char* data, size_t size);

components/mosquitto/examples/serverless_mqtt/main/peer_impl_juice.c

@@ -0,0 +1,283 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include <stdio.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/event_groups.h"
+#include "mqtt_client.h"
+#include "esp_wifi.h"
+#include "esp_log.h"
+#include "esp_check.h"
+#include "juice/juice.h"
+#include "cJSON.h"
+#include "peer_impl.h"
+
+#if defined(CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1)
+#define OUR_PEER "1"
+#define THEIR_PEER "2"
+#elif defined(CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER2)
+#define OUR_PEER "2"
+#define THEIR_PEER "1"
+#endif
+
+#define PEER_SYNC0 BIT(0)
+#define PEER_SYNC1 BIT(1)
+#define PEER_SYNC2 BIT(2)
+#define PEER_FAIL  BIT(3)
+#define PEER_GATHER_DONE  BIT(4)
+#define PEER_DESC_PUBLISHED  BIT(5)
+#define PEER_CONNECTED  BIT(6)
+
+#define SYNC_BITS (PEER_SYNC1 | PEER_SYNC2 | PEER_FAIL)
+
+#define PUBLISH_SYNC_TOPIC CONFIG_EXAMPLE_MQTT_SYNC_TOPIC OUR_PEER
+#define SUBSCRIBE_SYNC_TOPIC CONFIG_EXAMPLE_MQTT_SYNC_TOPIC THEIR_PEER
+#define MAX_BUFFER_SIZE JUICE_MAX_SDP_STRING_LEN
+
+static const char *TAG = "serverless_mqtt" OUR_PEER;
+static char s_buffer[MAX_BUFFER_SIZE];
+static EventGroupHandle_t s_state = NULL;
+static juice_agent_t *s_agent = NULL;
+static cJSON *s_peer_desc_json = NULL;
+static char *s_peer_desc = NULL;
+static esp_mqtt_client_handle_t s_local_mqtt = NULL;
+static on_peer_recv_t s_on_recv = NULL;
+
+char *wifi_get_ipv4(wifi_interface_t interface);
+static esp_err_t sync_peers(void);
+static esp_err_t create_candidates(void);
+
+void peer_get_buffer(char ** buffer, size_t *buffer_len)
+{
+    if (buffer && buffer_len) {
+        *buffer = s_buffer;
+        *buffer_len = MAX_BUFFER_SIZE;
+    }
+}
+
+void peer_send(char* data, size_t size)
+{
+    juice_send(s_agent, data, size);
+}
+
+esp_err_t peer_init(on_peer_recv_t cb)
+{
+    esp_err_t ret = ESP_FAIL;
+    ESP_GOTO_ON_FALSE(cb, ESP_ERR_INVALID_ARG, err, TAG, "Invalid peer receive callback");
+    s_on_recv = cb;
+    ESP_GOTO_ON_ERROR(create_candidates(), err, TAG, "Failed to create juice candidates");
+    ESP_GOTO_ON_ERROR(sync_peers(), err, TAG, "Failed to sync with the other peer");
+    EventBits_t bits = xEventGroupWaitBits(s_state, PEER_FAIL | PEER_CONNECTED, pdFALSE, pdFALSE, pdMS_TO_TICKS(90000));
+    if (bits & PEER_CONNECTED) {
+        ESP_LOGI(TAG, "Peer is connected!");
+        return ESP_OK;
+    }
+err:
+    ESP_LOGE(TAG, "Failed to init peer");
+    return ret;
+}
+
+static void mqtt_event_handler(void *handler_args, esp_event_base_t base, int32_t event_id, void *event_data)
+{
+    esp_mqtt_event_handle_t event = event_data;
+    esp_mqtt_client_handle_t client = event->client;
+    switch ((esp_mqtt_event_id_t)event_id) {
+    case MQTT_EVENT_CONNECTED:
+        ESP_LOGI(TAG, "MQTT_EVENT_CONNECTED");
+        if (esp_mqtt_client_subscribe(client, SUBSCRIBE_SYNC_TOPIC, 1) < 0) {
+            ESP_LOGE(TAG, "Failed to subscribe to the sync topic");
+        }
+        xEventGroupSetBits(s_state, PEER_SYNC0);
+        break;
+    case MQTT_EVENT_DISCONNECTED:
+        ESP_LOGI(TAG, "MQTT_EVENT_DISCONNECTED");
+        xEventGroupSetBits(s_state, PEER_FAIL);
+        break;
+
+    case MQTT_EVENT_DATA:
+        ESP_LOGI(TAG, "MQTT_EVENT_DATA");
+        printf("TOPIC=%.*s\r\n", event->topic_len, event->topic);
+        printf("DATA=%.*s\r\n", event->data_len, event->data);
+        if (s_state == NULL || memcmp(event->topic, SUBSCRIBE_SYNC_TOPIC, event->topic_len) != 0) {
+            break;
+        }
+        EventBits_t bits = xEventGroupGetBits(s_state);
+        if (event->data_len > 1 && s_agent) {
+            cJSON *root = cJSON_Parse(event->data);
+            if (root == NULL) {
+                break;
+            }
+            cJSON *desc = cJSON_GetObjectItem(root, "desc");
+            if (desc == NULL) {
+                cJSON_Delete(root);
+                break;
+            }
+            printf("desc->valuestring:%s\n", desc->valuestring);
+            juice_set_remote_description(s_agent, desc->valuestring);
+            char cand_name[] = "cand0";
+            while (true) {
+                cJSON *cand = cJSON_GetObjectItem(root, cand_name);
+                if (cand == NULL) {
+                    break;
+                }
+                printf("%s: cand->valuestring:%s\n", cand_name, cand->valuestring);
+                juice_add_remote_candidate(s_agent, cand->valuestring);
+                cand_name[4]++;
+            }
+            cJSON_Delete(root);
+            xEventGroupSetBits(s_state, PEER_DESC_PUBLISHED); // this will complete the sync process
+            // and destroy the mqtt client
+        }
+#ifdef CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1
+        if (event->data_len == 1 && event->data[0] == '1' && (bits & PEER_SYNC2) == 0) {
+            if (esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, "2", 1, 1, 0) >= 0) {
+                xEventGroupSetBits(s_state, PEER_SYNC2);
+            } else {
+                xEventGroupSetBits(s_state, PEER_FAIL);
+            }
+        }
+#else
+        if (event->data_len == 1 && event->data[0] == '0' && (bits & PEER_SYNC1) == 0) {
+            if (esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, "1", 1, 1, 0) >= 0) {
+                xEventGroupSetBits(s_state, PEER_SYNC1);
+            }  else {
+                xEventGroupSetBits(s_state, PEER_FAIL);
+            }
+        } else if (event->data_len == 1 && event->data[0] == '2' && (bits & PEER_SYNC2) == 0) {
+            xEventGroupSetBits(s_state, PEER_SYNC2);
+        }
+#endif
+        break;
+    case MQTT_EVENT_ERROR:
+        ESP_LOGI(TAG, "MQTT_EVENT_ERROR");
+        xEventGroupSetBits(s_state, PEER_FAIL);
+        break;
+    default:
+        ESP_LOGI(TAG, "Other event id:%d", event->event_id);
+        break;
+    }
+}
+
+static esp_err_t sync_peers(void)
+{
+    esp_err_t ret = ESP_OK;
+    esp_mqtt_client_config_t mqtt_cfg = {
+        .broker.address.uri = CONFIG_EXAMPLE_MQTT_BROKER_URI,
+        .task.stack_size = CONFIG_EXAMPLE_MQTT_CLIENT_STACK_SIZE,
+    };
+    esp_mqtt_client_handle_t client = esp_mqtt_client_init(&mqtt_cfg);
+    ESP_GOTO_ON_FALSE(client, ESP_ERR_NO_MEM, err, TAG, "Failed to create mqtt client");
+    ESP_GOTO_ON_ERROR(esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, NULL),
+                      err, TAG, "Failed to register mqtt event handler");
+    ESP_GOTO_ON_ERROR(esp_mqtt_client_start(client), err, TAG, "Failed to start mqtt client");
+    ESP_GOTO_ON_FALSE(xEventGroupWaitBits(s_state, PEER_SYNC0, pdTRUE, pdTRUE, pdMS_TO_TICKS(10000)),
+                      ESP_FAIL, err, TAG, "Failed to connect to the sync broker");
+    ESP_LOGI(TAG, "Waiting for the other peer...");
+    const int max_sync_retry = 60;
+    int retry = 0;
+    while (true) {
+        EventBits_t bits = xEventGroupWaitBits(s_state, SYNC_BITS, pdTRUE, pdFALSE, pdMS_TO_TICKS(1000));
+        if (bits & PEER_SYNC2) {
+            break;
+        }
+        if (bits & PEER_SYNC1) {
+            continue;
+        }
+        ESP_GOTO_ON_FALSE((bits & PEER_FAIL) == 0, ESP_FAIL, err, TAG, "Failed to sync with the other peer");
+        ESP_GOTO_ON_FALSE(retry++ < max_sync_retry, ESP_FAIL, err, TAG, "Failed to sync after %d seconds", retry);
+#ifdef CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1
+        ESP_RETURN_ON_FALSE(esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, "0", 1, 1, 0) >= 0,
+                            ESP_FAIL, TAG, "Failed to publish mqtt message");
+#endif
+    }
+    ESP_LOGI(TAG, "Sync done");
+    ESP_RETURN_ON_FALSE(esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, s_peer_desc, 0, 1, 0) >= 0,
+                        ESP_FAIL, TAG, "Failed to publish peer's description");
+    ESP_LOGI(TAG, "Waiting for the other peer description and candidates...");
+    ESP_GOTO_ON_FALSE(xEventGroupWaitBits(s_state, PEER_DESC_PUBLISHED, pdTRUE, pdTRUE, pdMS_TO_TICKS(10000)),
+                      ESP_FAIL, err, TAG, "Timeout in waiting for the other peer candidates");
+err:
+    free(s_peer_desc);
+    esp_mqtt_client_destroy(client);
+    return ret;
+}
+
+static void juice_state(juice_agent_t *agent, juice_state_t state, void *user_ptr)
+{
+    ESP_LOGI(TAG, "JUICE state change: %s", juice_state_to_string(state));
+    if (state == JUICE_STATE_CONNECTED) {
+        xEventGroupSetBits(s_state, PEER_CONNECTED);
+    } else if (state == JUICE_STATE_FAILED || state == JUICE_STATE_DISCONNECTED) {
+        esp_restart();
+    }
+}
+
+static void juice_candidate(juice_agent_t *agent, const char *sdp, void *user_ptr)
+{
+    static uint8_t cand_nr = 0;
+    if (s_peer_desc_json && cand_nr < 10) { // supporting only 10 candidates
+        char cand_name[] = "cand0";
+        cand_name[4] += cand_nr++;
+        cJSON_AddStringToObject(s_peer_desc_json, cand_name, sdp);
+    }
+}
+
+static void juice_gathering_done(juice_agent_t *agent, void *user_ptr)
+{
+    ESP_LOGI(TAG, "Gathering done");
+    if (s_state) {
+        xEventGroupSetBits(s_state, PEER_GATHER_DONE);
+    }
+}
+
+
+
+static void juice_recv(juice_agent_t *agent, const char *data, size_t size, void *user_ptr)
+{
+    if (s_local_mqtt) {
+        s_on_recv(data, size);
+    } else {
+        ESP_LOGI(TAG, "No local mqtt client, dropping data");
+    }
+}
+
+static esp_err_t create_candidates(void)
+{
+    ESP_RETURN_ON_FALSE(s_state = xEventGroupCreate(), ESP_ERR_NO_MEM, TAG, "Failed to create state event group");
+    s_peer_desc_json = cJSON_CreateObject();
+    esp_err_t ret = ESP_OK;
+    juice_set_log_level(JUICE_LOG_LEVEL_INFO);
+    juice_config_t config = { .stun_server_host = CONFIG_EXAMPLE_STUN_SERVER,
+                              .bind_address = wifi_get_ipv4(WIFI_IF_STA),
+                              .stun_server_port = 19302,
+                              .cb_state_changed = juice_state,
+                              .cb_candidate = juice_candidate,
+                              .cb_gathering_done = juice_gathering_done,
+                              .cb_recv = juice_recv,
+                            };
+
+    s_agent = juice_create(&config);
+    ESP_RETURN_ON_FALSE(s_agent, ESP_FAIL, TAG, "Failed to create juice agent");
+    ESP_GOTO_ON_FALSE(juice_get_local_description(s_agent, s_buffer, MAX_BUFFER_SIZE) == JUICE_ERR_SUCCESS,
+                      ESP_FAIL, err, TAG, "Failed to get local description");
+    ESP_LOGI(TAG, "desc: %s", s_buffer);
+    cJSON_AddStringToObject(s_peer_desc_json, "desc", s_buffer);
+
+    ESP_GOTO_ON_FALSE(juice_gather_candidates(s_agent) == JUICE_ERR_SUCCESS,
+                      ESP_FAIL, err, TAG, "Failed to start gathering candidates");
+    ESP_GOTO_ON_FALSE(xEventGroupWaitBits(s_state, PEER_GATHER_DONE, pdTRUE, pdTRUE, pdMS_TO_TICKS(30000)),
+                      ESP_FAIL, err, TAG, "Failed to connect to the sync broker");
+    s_peer_desc = cJSON_Print(s_peer_desc_json);
+    ESP_LOGI(TAG, "desc: %s", s_peer_desc);
+    cJSON_Delete(s_peer_desc_json);
+    return ESP_OK;
+
+err:
+    juice_destroy(s_agent);
+    s_agent = NULL;
+    cJSON_Delete(s_peer_desc_json);
+    s_peer_desc_json = NULL;
+    return ret;
+}

components/mosquitto/examples/serverless_mqtt/main/peer_impl_webrtc.c

@@ -0,0 +1,248 @@
+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Unlicense OR CC0-1.0
+ */
+#include "media_lib_os.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/event_groups.h"
+#include "media_lib_adapter.h"
+#include "media_lib_os.h"
+#include "esp_log.h"
+#include "esp_webrtc_defaults.h"
+#include "esp_peer_default.h"
+#include "common.h"
+#include "esp_check.h"
+#include "peer_impl.h"
+#include "sdkconfig.h"
+
+#define WEBRTC_URL (CONFIG_EXAMPLE_WEBRTC_URL CONFIG_EXAMPLE_WEBRTC_ROOM_ID)
+#define PEER_CONNECTED      BIT(0)
+#define PEER_DISCONNECTED   BIT(1)
+#define MAX_BUFFER_SIZE     (4*1024)
+
+static EventGroupHandle_t s_state = NULL;
+static const char *TAG = "serverless_mqtt_webrtc";
+
+void peer_get_buffer(char ** buffer, size_t *buffer_len)
+{
+    static char s_buffer[MAX_BUFFER_SIZE];
+    if (buffer && buffer_len) {
+        *buffer = s_buffer;
+        *buffer_len = MAX_BUFFER_SIZE;
+    }
+}
+
+static int start_webrtc(char *url);
+static int stop_webrtc(void);
+
+static on_peer_recv_t s_on_recv = NULL;
+static esp_peer_signaling_handle_t signaling = NULL;
+static esp_peer_handle_t peer = NULL;
+static bool peer_running = false;
+
+static void thread_scheduler(const char *thread_name, media_lib_thread_cfg_t *thread_cfg)
+{
+    if (strcmp(thread_name, "pc_task") == 0) {
+        thread_cfg->stack_size = 25 * 1024;
+        thread_cfg->priority = 18;
+        thread_cfg->core_id = 1;
+    }
+}
+
+esp_err_t peer_init(on_peer_recv_t cb)
+{
+    esp_err_t ret = ESP_OK;
+    s_on_recv = cb;
+    s_state = xEventGroupCreate();
+    media_lib_add_default_adapter();
+    media_lib_thread_set_schedule_cb(thread_scheduler);
+    ESP_RETURN_ON_FALSE(s_state, ESP_ERR_NO_MEM, TAG, "Failed to create state event group");
+    ESP_GOTO_ON_FALSE(start_webrtc(WEBRTC_URL) == ESP_PEER_ERR_NONE, ESP_FAIL, err, TAG, "Failed to start webRTC");
+    ESP_LOGI(TAG, "Waiting for peer to connect");
+    int i = 0;
+    while (1) {
+        EventBits_t bits = xEventGroupWaitBits(s_state, PEER_CONNECTED, pdFALSE, pdFALSE, pdMS_TO_TICKS(1000));
+        if (bits & PEER_CONNECTED) {
+            ESP_LOGI(TAG, "Peer is connected!");
+            return ret;
+        }
+        ESP_GOTO_ON_FALSE(i++ < 100, ESP_ERR_TIMEOUT, err, TAG, "Peer connection timeout");
+        if (peer) {
+            esp_peer_query(peer);
+        }
+    }
+
+err:
+    vEventGroupDelete(s_state);
+    return ret;
+}
+
+
+static int peer_state_handler(esp_peer_state_t state, void* ctx)
+{
+    ESP_LOGI(TAG, "Peer state: %d", state);
+    if (state == ESP_PEER_STATE_CONNECTED) {
+        xEventGroupSetBits(s_state, PEER_CONNECTED);
+    } else if (state == ESP_PEER_STATE_DISCONNECTED) {
+        xEventGroupSetBits(s_state, PEER_DISCONNECTED);
+    }
+    return 0;
+}
+
+static int peer_msg_handler(esp_peer_msg_t* msg, void* ctx)
+{
+    if (msg->type == ESP_PEER_MSG_TYPE_SDP) {
+        // Send local SDP to signaling server
+        esp_peer_signaling_send_msg(signaling, (esp_peer_signaling_msg_t *)msg);
+    }
+    return 0;
+}
+
+static int peer_video_info_handler(esp_peer_video_stream_info_t* info, void* ctx)
+{
+    return 0;
+}
+
+static int peer_audio_info_handler(esp_peer_audio_stream_info_t* info, void* ctx)
+{
+    return 0;
+}
+
+static int peer_audio_data_handler(esp_peer_audio_frame_t* frame, void* ctx)
+{
+    ESP_LOGI(TAG, "Audio Sequence %d(%d)", (int)frame->pts, (int)frame->data[0]);
+    return 0;
+}
+
+static int peer_video_data_handler(esp_peer_video_frame_t* frame, void* ctx)
+{
+    return 0;
+}
+
+static int peer_data_handler(esp_peer_data_frame_t* frame, void* ctx)
+{
+    if (frame && frame->size > 0) {
+        s_on_recv((char*)frame->data, frame->size);
+    }
+    return 0;
+}
+
+static void pc_task(void *arg)
+{
+    while (peer_running) {
+        esp_peer_main_loop(peer);
+        media_lib_thread_sleep(20);
+    }
+    media_lib_thread_destroy(NULL);
+}
+
+static int signaling_ice_info_handler(esp_peer_signaling_ice_info_t* info, void* ctx)
+{
+    if (peer == NULL) {
+        esp_peer_default_cfg_t peer_cfg = {
+            .agent_recv_timeout = 500,
+        };
+        esp_peer_cfg_t cfg = {
+            .server_lists = &info->server_info,
+            .server_num = 1,
+            .audio_dir = ESP_PEER_MEDIA_DIR_SEND_RECV,
+            .audio_info = {
+                .codec = ESP_PEER_AUDIO_CODEC_G711A,
+            },
+            .enable_data_channel = true,
+            .role = info->is_initiator ? ESP_PEER_ROLE_CONTROLLING : ESP_PEER_ROLE_CONTROLLED,
+            .on_state = peer_state_handler,
+            .on_msg = peer_msg_handler,
+            .on_video_info = peer_video_info_handler,
+            .on_audio_info = peer_audio_info_handler,
+            .on_video_data = peer_video_data_handler,
+            .on_audio_data = peer_audio_data_handler,
+            .on_data = peer_data_handler,
+            .ctx = ctx,
+            .extra_cfg = &peer_cfg,
+            .extra_size = sizeof(esp_peer_default_cfg_t),
+        };
+        int ret = esp_peer_open(&cfg, esp_peer_get_default_impl(), &peer);
+        if (ret != ESP_PEER_ERR_NONE) {
+            return ret;
+        }
+        media_lib_thread_handle_t thread = NULL;
+        peer_running = true;
+        media_lib_thread_create_from_scheduler(&thread, "pc_task", pc_task, NULL);
+        if (thread == NULL) {
+            peer_running = false;
+        }
+    }
+    return 0;
+}
+
+static int signaling_connected_handler(void* ctx)
+{
+    if (peer) {
+        return esp_peer_new_connection(peer);
+    }
+    return 0;
+}
+
+static int signaling_msg_handler(esp_peer_signaling_msg_t* msg, void* ctx)
+{
+    if (msg->type == ESP_PEER_SIGNALING_MSG_BYE) {
+        esp_peer_close(peer);
+        peer = NULL;
+    } else if (msg->type == ESP_PEER_SIGNALING_MSG_SDP) {
+        // Receive remote SDP
+        if (peer) {
+            esp_peer_send_msg(peer, (esp_peer_msg_t*)msg);
+        }
+    }
+    return 0;
+}
+
+static int signaling_close_handler(void *ctx)
+{
+    return 0;
+}
+
+static int start_signaling(char* url)
+{
+    esp_peer_signaling_cfg_t cfg = {
+        .signal_url = url,
+        .on_ice_info = signaling_ice_info_handler,
+        .on_connected = signaling_connected_handler,
+        .on_msg = signaling_msg_handler,
+        .on_close = signaling_close_handler,
+    };
+    // Use APPRTC signaling
+    return esp_peer_signaling_start(&cfg, esp_signaling_get_apprtc_impl(), &signaling);
+}
+
+static int start_webrtc(char *url)
+{
+    stop_webrtc();
+    return start_signaling(url);
+}
+
+static int stop_webrtc(void)
+{
+    peer_running = false;
+    if (peer) {
+        esp_peer_close(peer);
+        peer = NULL;
+    }
+    if (signaling) {
+        esp_peer_signaling_stop(signaling);
+        signaling = NULL;
+    }
+    return 0;
+}
+
+void peer_send(char* data, size_t size)
+{
+    esp_peer_data_frame_t data_frame = {
+        .type = ESP_PEER_DATA_CHANNEL_DATA,
+        .data = (uint8_t*)data,
+        .size = size,
+    };
+    esp_peer_send_data(peer, &data_frame);
+}

components/mosquitto/examples/serverless_mqtt/main/serverless_mqtt.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -13,30 +13,9 @@
 #include "esp_check.h"
 #include "esp_sleep.h"
 #include "mosq_broker.h"
-#include "juice/juice.h"
-#include "cJSON.h"
+#include "peer_impl.h"
 
-#if defined(CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1)
-#define OUR_PEER "1"
-#define THEIR_PEER "2"
-#elif defined(CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER2)
-#define OUR_PEER "2"
-#define THEIR_PEER "1"
-#endif
-
-#define PEER_SYNC0 BIT(0)
-#define PEER_SYNC1 BIT(1)
-#define PEER_SYNC2 BIT(2)
-#define PEER_FAIL  BIT(3)
-#define PEER_GATHER_DONE  BIT(4)
-#define PEER_DESC_PUBLISHED  BIT(5)
-#define PEER_CONNECTED  BIT(6)
-
-#define SYNC_BITS (PEER_SYNC1 | PEER_SYNC2 | PEER_FAIL)
-
-#define PUBLISH_SYNC_TOPIC CONFIG_EXAMPLE_MQTT_SYNC_TOPIC OUR_PEER
-#define SUBSCRIBE_SYNC_TOPIC CONFIG_EXAMPLE_MQTT_SYNC_TOPIC THEIR_PEER
-#define MAX_BUFFER_SIZE JUICE_MAX_SDP_STRING_LEN
+#define ALIGN(size) (((size) + 3U) & ~(3U))
 
 typedef struct message_wrap {
     uint16_t topic_len;
@@ -44,196 +23,18 @@ typedef struct message_wrap {
     char data[];
 } __attribute__((packed)) message_wrap_t;
 
-static const char *TAG = "serverless_mqtt" OUR_PEER;
-static char s_buffer[MAX_BUFFER_SIZE];
-static EventGroupHandle_t s_state = NULL;
-static juice_agent_t *s_agent = NULL;
-static cJSON *s_peer_desc_json = NULL;
-static char *s_peer_desc = NULL;
+static const char *TAG = "serverless_mqtt";
+
 static esp_mqtt_client_handle_t s_local_mqtt = NULL;
 
 char *wifi_get_ipv4(wifi_interface_t interface);
 esp_err_t wifi_connect(void);
-static esp_err_t sync_peers(void);
-static esp_err_t create_candidates(void);
 static esp_err_t create_local_client(void);
 static esp_err_t create_local_broker(void);
 
-void app_main(void)
-{
-    __attribute__((__unused__)) esp_err_t ret;
-    ESP_GOTO_ON_ERROR(wifi_connect(), err, TAG, "Failed to initialize WiFi");
-    ESP_GOTO_ON_ERROR(create_local_broker(), err, TAG, "Failed to create local broker");
-    ESP_GOTO_ON_ERROR(create_candidates(), err, TAG, "Failed to create juice candidates");
-    ESP_GOTO_ON_ERROR(sync_peers(), err, TAG, "Failed to sync with the other peer");
-    EventBits_t bits = xEventGroupWaitBits(s_state, PEER_FAIL | PEER_CONNECTED, pdFALSE, pdFALSE, pdMS_TO_TICKS(90000));
-    if (bits & PEER_CONNECTED) {
-        ESP_LOGI(TAG, "Peer is connected!");
-        ESP_GOTO_ON_ERROR(create_local_client(), err, TAG, "Failed to create forwarding mqtt client");
-        ESP_LOGI(TAG, "Everything is ready, exiting main task");
-        return;
-    }
-err:
-    ESP_LOGE(TAG, "Non recoverable error, going to sleep for some time (random, max 20s)");
-    esp_deep_sleep(1000000LL * (esp_random() % 20));
-}
+esp_err_t peer_init(on_peer_recv_t cb);
 
-static void mqtt_event_handler(void *handler_args, esp_event_base_t base, int32_t event_id, void *event_data)
-{
-    esp_mqtt_event_handle_t event = event_data;
-    esp_mqtt_client_handle_t client = event->client;
-    switch ((esp_mqtt_event_id_t)event_id) {
-    case MQTT_EVENT_CONNECTED:
-        ESP_LOGI(TAG, "MQTT_EVENT_CONNECTED");
-        if (esp_mqtt_client_subscribe(client, SUBSCRIBE_SYNC_TOPIC, 1) < 0) {
-            ESP_LOGE(TAG, "Failed to subscribe to the sync topic");
-        }
-        xEventGroupSetBits(s_state, PEER_SYNC0);
-        break;
-    case MQTT_EVENT_DISCONNECTED:
-        ESP_LOGI(TAG, "MQTT_EVENT_DISCONNECTED");
-        xEventGroupSetBits(s_state, PEER_FAIL);
-        break;
-
-    case MQTT_EVENT_DATA:
-        ESP_LOGI(TAG, "MQTT_EVENT_DATA");
-        printf("TOPIC=%.*s\r\n", event->topic_len, event->topic);
-        printf("DATA=%.*s\r\n", event->data_len, event->data);
-        if (s_state == NULL || memcmp(event->topic, SUBSCRIBE_SYNC_TOPIC, event->topic_len) != 0) {
-            break;
-        }
-        EventBits_t bits = xEventGroupGetBits(s_state);
-        if (event->data_len > 1 && s_agent) {
-            cJSON *root = cJSON_Parse(event->data);
-            if (root == NULL) {
-                break;
-            }
-            cJSON *desc = cJSON_GetObjectItem(root, "desc");
-            if (desc == NULL) {
-                cJSON_Delete(root);
-                break;
-            }
-            printf("desc->valuestring:%s\n", desc->valuestring);
-            juice_set_remote_description(s_agent, desc->valuestring);
-            char cand_name[] = "cand0";
-            while (true) {
-                cJSON *cand = cJSON_GetObjectItem(root, cand_name);
-                if (cand == NULL) {
-                    break;
-                }
-                printf("%s: cand->valuestring:%s\n", cand_name, cand->valuestring);
-                juice_add_remote_candidate(s_agent, cand->valuestring);
-                cand_name[4]++;
-            }
-            cJSON_Delete(root);
-            xEventGroupSetBits(s_state, PEER_DESC_PUBLISHED); // this will complete the sync process
-            // and destroy the mqtt client
-        }
-#ifdef CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1
-        if (event->data_len == 1 && event->data[0] == '1' && (bits & PEER_SYNC2) == 0) {
-            if (esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, "2", 1, 1, 0) >= 0) {
-                xEventGroupSetBits(s_state, PEER_SYNC2);
-            } else {
-                xEventGroupSetBits(s_state, PEER_FAIL);
-            }
-        }
-#else
-        if (event->data_len == 1 && event->data[0] == '0' && (bits & PEER_SYNC1) == 0) {
-            if (esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, "1", 1, 1, 0) >= 0) {
-                xEventGroupSetBits(s_state, PEER_SYNC1);
-            }  else {
-                xEventGroupSetBits(s_state, PEER_FAIL);
-            }
-        } else if (event->data_len == 1 && event->data[0] == '2' && (bits & PEER_SYNC2) == 0) {
-            xEventGroupSetBits(s_state, PEER_SYNC2);
-        }
-#endif
-        break;
-    case MQTT_EVENT_ERROR:
-        ESP_LOGI(TAG, "MQTT_EVENT_ERROR");
-        xEventGroupSetBits(s_state, PEER_FAIL);
-        break;
-    default:
-        ESP_LOGI(TAG, "Other event id:%d", event->event_id);
-        break;
-    }
-}
-
-static esp_err_t sync_peers(void)
-{
-    esp_err_t ret = ESP_OK;
-    esp_mqtt_client_config_t mqtt_cfg = {
-        .broker.address.uri = CONFIG_EXAMPLE_MQTT_BROKER_URI,
-        .task.stack_size = CONFIG_EXAMPLE_MQTT_CLIENT_STACK_SIZE,
-    };
-    esp_mqtt_client_handle_t client = esp_mqtt_client_init(&mqtt_cfg);
-    ESP_GOTO_ON_FALSE(client, ESP_ERR_NO_MEM, err, TAG, "Failed to create mqtt client");
-    ESP_GOTO_ON_ERROR(esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, NULL),
-                      err, TAG, "Failed to register mqtt event handler");
-    ESP_GOTO_ON_ERROR(esp_mqtt_client_start(client), err, TAG, "Failed to start mqtt client");
-    ESP_GOTO_ON_FALSE(xEventGroupWaitBits(s_state, PEER_SYNC0, pdTRUE, pdTRUE, pdMS_TO_TICKS(10000)),
-                      ESP_FAIL, err, TAG, "Failed to connect to the sync broker");
-    ESP_LOGI(TAG, "Waiting for the other peer...");
-    const int max_sync_retry = 60;
-    int retry = 0;
-    while (true) {
-        EventBits_t bits = xEventGroupWaitBits(s_state, SYNC_BITS, pdTRUE, pdFALSE, pdMS_TO_TICKS(1000));
-        if (bits & PEER_SYNC2) {
-            break;
-        }
-        if (bits & PEER_SYNC1) {
-            continue;
-        }
-        ESP_GOTO_ON_FALSE((bits & PEER_FAIL) == 0, ESP_FAIL, err, TAG, "Failed to sync with the other peer");
-        ESP_GOTO_ON_FALSE(retry++ < max_sync_retry, ESP_FAIL, err, TAG, "Failed to sync after %d seconds", retry);
-#ifdef CONFIG_EXAMPLE_SERVERLESS_ROLE_PEER1
-        ESP_RETURN_ON_FALSE(esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, "0", 1, 1, 0) >= 0,
-                            ESP_FAIL, TAG, "Failed to publish mqtt message");
-#endif
-    }
-    ESP_LOGI(TAG, "Sync done");
-    ESP_RETURN_ON_FALSE(esp_mqtt_client_publish(client, PUBLISH_SYNC_TOPIC, s_peer_desc, 0, 1, 0) >= 0,
-                        ESP_FAIL, TAG, "Failed to publish peer's description");
-    ESP_LOGI(TAG, "Waiting for the other peer description and candidates...");
-    ESP_GOTO_ON_FALSE(xEventGroupWaitBits(s_state, PEER_DESC_PUBLISHED, pdTRUE, pdTRUE, pdMS_TO_TICKS(10000)),
-                      ESP_FAIL, err, TAG, "Timeout in waiting for the other peer candidates");
-err:
-    free(s_peer_desc);
-    esp_mqtt_client_destroy(client);
-    return ret;
-}
-
-static void juice_state(juice_agent_t *agent, juice_state_t state, void *user_ptr)
-{
-    ESP_LOGI(TAG, "JUICE state change: %s", juice_state_to_string(state));
-    if (state == JUICE_STATE_CONNECTED) {
-        xEventGroupSetBits(s_state, PEER_CONNECTED);
-    } else if (state == JUICE_STATE_FAILED || state == JUICE_STATE_DISCONNECTED) {
-        esp_restart();
-    }
-}
-
-static void juice_candidate(juice_agent_t *agent, const char *sdp, void *user_ptr)
-{
-    static uint8_t cand_nr = 0;
-    if (s_peer_desc_json && cand_nr < 10) { // supporting only 10 candidates
-        char cand_name[] = "cand0";
-        cand_name[4] += cand_nr++;
-        cJSON_AddStringToObject(s_peer_desc_json, cand_name, sdp);
-    }
-}
-
-static void juice_gathering_done(juice_agent_t *agent, void *user_ptr)
-{
-    ESP_LOGI(TAG, "Gathering done");
-    if (s_state) {
-        xEventGroupSetBits(s_state, PEER_GATHER_DONE);
-    }
-}
-
-#define ALIGN(size) (((size) + 3U) & ~(3U))
-
-static void juice_recv(juice_agent_t *agent, const char *data, size_t size, void *user_ptr)
+static void peer_recv(const char *data, size_t size)
 {
     if (s_local_mqtt) {
         message_wrap_t *message = (message_wrap_t *)data;
@@ -250,45 +51,21 @@ static void juice_recv(juice_agent_t *agent, const char *data, size_t size, void
         ESP_LOGI(TAG, "forwarding remote message: payload:%.*s", payload_len, payload);
         esp_mqtt_client_publish(s_local_mqtt, topic, payload, payload_len, 0, 0);
     }
+
 }
 
-static esp_err_t create_candidates(void)
+void app_main(void)
 {
-    ESP_RETURN_ON_FALSE(s_state = xEventGroupCreate(), ESP_ERR_NO_MEM, TAG, "Failed to create state event group");
-    s_peer_desc_json = cJSON_CreateObject();
-    esp_err_t ret = ESP_OK;
-    juice_set_log_level(JUICE_LOG_LEVEL_INFO);
-    juice_config_t config = { .stun_server_host = CONFIG_EXAMPLE_STUN_SERVER,
-                              .bind_address = wifi_get_ipv4(WIFI_IF_STA),
-                              .stun_server_port = 19302,
-                              .cb_state_changed = juice_state,
-                              .cb_candidate = juice_candidate,
-                              .cb_gathering_done = juice_gathering_done,
-                              .cb_recv = juice_recv,
-                            };
-
-    s_agent = juice_create(&config);
-    ESP_RETURN_ON_FALSE(s_agent, ESP_FAIL, TAG, "Failed to create juice agent");
-    ESP_GOTO_ON_FALSE(juice_get_local_description(s_agent, s_buffer, MAX_BUFFER_SIZE) == JUICE_ERR_SUCCESS,
-                      ESP_FAIL, err, TAG, "Failed to get local description");
-    ESP_LOGI(TAG, "desc: %s", s_buffer);
-    cJSON_AddStringToObject(s_peer_desc_json, "desc", s_buffer);
-
-    ESP_GOTO_ON_FALSE(juice_gather_candidates(s_agent) == JUICE_ERR_SUCCESS,
-                      ESP_FAIL, err, TAG, "Failed to start gathering candidates");
-    ESP_GOTO_ON_FALSE(xEventGroupWaitBits(s_state, PEER_GATHER_DONE, pdTRUE, pdTRUE, pdMS_TO_TICKS(30000)),
-                      ESP_FAIL, err, TAG, "Failed to connect to the sync broker");
-    s_peer_desc = cJSON_Print(s_peer_desc_json);
-    ESP_LOGI(TAG, "desc: %s", s_peer_desc);
-    cJSON_Delete(s_peer_desc_json);
-    return ESP_OK;
-
+    __attribute__((__unused__)) esp_err_t ret;
+    ESP_GOTO_ON_ERROR(wifi_connect(), err, TAG, "Failed to initialize WiFi");
+    ESP_GOTO_ON_ERROR(create_local_broker(), err, TAG, "Failed to create local broker");
+    ESP_GOTO_ON_ERROR(peer_init(peer_recv), err, TAG, "Failed to init peer library");
+    ESP_GOTO_ON_ERROR(create_local_client(), err, TAG, "Failed to create forwarding mqtt client");
+    ESP_LOGI(TAG, "Everything is ready, exiting main task");
+    return;
 err:
-    juice_destroy(s_agent);
-    s_agent = NULL;
-    cJSON_Delete(s_peer_desc_json);
-    s_peer_desc_json = NULL;
-    return ret;
+    ESP_LOGE(TAG, "Non recoverable error, going to sleep for some time (random, max 20s)");
+    esp_deep_sleep(1000000LL * (esp_random() % 20));
 }
 
 static void local_handler(void *args, esp_event_base_t base, int32_t id, void *data)
@@ -335,18 +112,26 @@ err:
 
 static void handle_message(char *client, char *topic, char *payload, int len, int qos, int retain)
 {
-    if (client && strcmp(client, "local_mqtt") == 0 ) {
+    if (client && strcmp(client, "local_mqtt") == 0) {
         // This is our little local client -- do not forward
         return;
     }
     ESP_LOGI(TAG, "handle_message topic:%s", topic);
     ESP_LOGI(TAG, "handle_message data:%.*s", len, payload);
     ESP_LOGI(TAG, "handle_message qos=%d, retain=%d", qos, retain);
-    if (s_local_mqtt && s_agent) {
+    if (s_local_mqtt) {
+        static char *s_buffer = NULL;
+        static size_t s_buffer_len = 0;
+        if (s_buffer == NULL || s_buffer_len == 0) {
+            peer_get_buffer(&s_buffer, &s_buffer_len);
+            if (s_buffer == NULL || s_buffer_len == 0) {
+                return;
+            }
+        }
         int topic_len = strlen(topic) + 1; // null term
         int topic_len_aligned = ALIGN(topic_len);
         int total_msg_len = 2 + 2 /* msg_wrap header */ + topic_len_aligned + len;
-        if (total_msg_len > MAX_BUFFER_SIZE) {
+        if (total_msg_len > s_buffer_len) {
             ESP_LOGE(TAG, "Fail to forward, message too long");
             return;
         }
@@ -356,7 +141,7 @@ static void handle_message(char *client, char *topic, char *payload, int len, in
 
         memcpy(s_buffer + 4, topic, topic_len);
         memcpy(s_buffer + 4 + topic_len_aligned, payload, len);
-        juice_send(s_agent, s_buffer, total_msg_len);
+        peer_send(s_buffer, total_msg_len);
     }
 }
 

components/mosquitto/examples/serverless_mqtt/main/wifi_connect.c

@@ -3,6 +3,8 @@
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
+#include "freertos/FreeRTOS.h"
+#include "freertos/event_groups.h"
 #include "nvs_flash.h"
 #include "esp_event.h"
 #include "esp_netif.h"

components/mosquitto/examples/serverless_mqtt/sdkconfig.ci.default

@@ -0,0 +1,2 @@
+CONFIG_EXAMPLE_PEER_LIB_ESP_PEER=n
+CONFIG_EXAMPLE_PEER_LIB_LIBJUICE=y

components/mosquitto/examples/serverless_mqtt/sdkconfig.ci.esp_peer

@@ -0,0 +1,5 @@
+CONFIG_IDF_TARGET="esp32"
+CONFIG_EXAMPLE_PEER_LIB_ESP_PEER=y
+CONFIG_EXAMPLE_PEER_LIB_LIBJUICE=n
+CONFIG_SPIRAM=y
+CONFIG_MBEDTLS_EXTERNAL_MEM_ALLOC=y

components/mosquitto/examples/serverless_mqtt/sdkconfig.defaults

@@ -1,3 +1,6 @@
 CONFIG_PARTITION_TABLE_SINGLE_APP_LARGE=y
 CONFIG_ESP_MAIN_TASK_STACK_SIZE=16384
 CONFIG_PTHREAD_TASK_STACK_SIZE_DEFAULT=32768
+CONFIG_LWIP_SNTP_MAX_SERVERS=2
+CONFIG_MBEDTLS_SSL_PROTO_DTLS=y
+CONFIG_MBEDTLS_SSL_DTLS_SRTP=y

components/mosquitto/idf_component.yml

@@ -1,4 +1,4 @@
-version: "2.0.20~2"
+version: "2.0.20~3"
 url: https://github.com/espressif/esp-protocols/tree/master/components/mosquitto
 description: The component provides a simple ESP32 port of mosquitto broker
 dependencies:

components/mosquitto/port/include/mosq_broker.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -7,6 +7,10 @@
 #include "mosquitto.h"
 #include "esp_tls.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct mosquitto__config;
 
 typedef void (*mosq_message_cb_t)(char *client, char *topic, char *data, int len, int qos, int retain);
@@ -17,7 +21,7 @@ typedef void (*mosq_message_cb_t)(char *client, char *topic, char *data, int len
  * structure.
  */
 struct mosq_broker_config {
-    char *host; /*!< Address on which the broker is listening for connections */
+    const char *host; /*!< Address on which the broker is listening for connections */
     int port;   /*!< Port number of the broker to listen to */
     esp_tls_cfg_server_t *tls_cfg;  /*!< ESP-TLS configuration (if TLS transport used)
                                      * Please refer to the ESP-TLS official documentation
@@ -48,3 +52,7 @@ int mosq_broker_run(struct mosq_broker_config *config);
  * @note After calling this API, function mosq_broker_run() unblocks and returns.
  */
 void mosq_broker_stop(void);
+
+#ifdef __cplusplus
+}
+#endif

components/mosquitto/port/net__esp_tls.c

@@ -3,7 +3,7 @@
  *
  * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
  *
- * SPDX-FileContributor: 2024 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileContributor: 2024-2025 Espressif Systems (Shanghai) CO LTD
  */
 
 /*
@@ -106,6 +106,9 @@ struct mosquitto *net__socket_accept(struct mosquitto__listener_sock *listensock
 
     new_sock = accept(listensock->sock, NULL, 0);
     if (new_sock == INVALID_SOCKET) {
+        if (errno == EAGAIN) {  // mosquitto tries to accept() in a loop until EAGAIN is returned
+            return NULL;
+        }
         log__printf(NULL, MOSQ_LOG_ERR,
                     "Unable to accept new connection, system socket count has been exceeded. Try increasing \"ulimit -n\" or equivalent.");
         return NULL;

components/mosquitto/port/priv_include/config.h

@@ -20,4 +20,4 @@
 #undef  isspace
 #define isspace(__c) (__ctype_lookup((int)__c)&_S)
 
-#define VERSION "v2.0.20~2"
+#define VERSION "v2.0.20~3"

examples/mqtt/main/Kconfig.projbuild

@@ -2,7 +2,7 @@ menu "Example Configuration"
 
     config BROKER_URL
         string "Broker URL"
-        default "mqtt://mqtt.eclipseprojects.io"
+        default "mqtt://test.mosquitto.org"
         help
             URL of the broker to connect to