ASIO: Initial version based on IDF 5.0 with history

Fix example for compatibility with C++20

* Original commit: espressif/esp-idf@9dba0476a0
* Original commit: espressif/esp-idf@157247f98f

.github/workflows/build_and_run_example_test_mdns.yml

@@ -13,8 +13,9 @@ jobs:
     container: espressif/idf:${{ matrix.idf_ver }}
     steps:
       - name: Checkout esp-protocols
-        uses: actions/checkout@master
+        uses: actions/checkout@v3
         with:
+          submodules: recursive
           path: esp-protocols
       - name: Build ${{ matrix.example }} with IDF-${{ matrix.idf_ver }} for ${{ matrix.idf_target }}
         env:
@@ -23,6 +24,7 @@ jobs:
         run: |
           . ${IDF_PATH}/export.sh
           cd $GITHUB_WORKSPACE/esp-protocols/components/mdns/examples/
+          idf.py set-target ${{ matrix.idf_target }} 
           cat sdkconfig.ci.eth_def >> sdkconfig.defaults
           idf.py build
           rm sdkconfig.defaults
@@ -32,4 +34,5 @@ jobs:
           cat sdkconfig.ci.eth_socket >> sdkconfig.defaults
           idf.py build
           cd $GITHUB_WORKSPACE/esp-protocols/components/mdns/tests/test_apps/
+          idf.py set-target ${{ matrix.idf_target }} 
           idf.py build

.github/workflows/build_and_run_example_test_websocket.yml

@@ -13,7 +13,9 @@ jobs:
     container: espressif/idf:${{ matrix.idf_ver }}
     steps:
       - name: Checkout esp-protocols
-        uses: actions/checkout@v1
+        uses: actions/checkout@v3
+        with:
+          submodules: recursive
       - name: Build ${{ matrix.example }} with IDF-${{ matrix.idf_ver }} for ${{ matrix.idf_target }}
         env:
           IDF_TARGET: ${{ matrix.idf_target }}

.github/workflows/build_asio.yml

@@ -0,0 +1,28 @@
+name: Build ASIO
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    strategy:
+      matrix:
+        idf_ver: ["latest"]
+        idf_target: ["esp32", "esp32s2"]
+        example: ["asio_chat", "async_request", "socks4", "ssl_client_server", "tcp_echo_server", "udp_echo_server"]
+
+    runs-on: ubuntu-20.04
+    container: espressif/idf:${{ matrix.idf_ver }}
+    steps:
+      - name: Checkout esp-protocols
+        uses: actions/checkout@v3
+        with:
+          path: esp-protocols
+      - name: Build ${{ matrix.example }} with IDF-${{ matrix.idf_ver }} for ${{ matrix.idf_target }}
+        env:
+          IDF_TARGET: ${{ matrix.idf_target }}
+        shell: bash
+        run: |
+          . ${IDF_PATH}/export.sh
+          cd $GITHUB_WORKSPACE/esp-protocols/components/asio/examples/${{ matrix.example }}
+          idf.py set-target ${{ matrix.idf_target }}
+          idf.py build

.github/workflows/publish-docs-component.yml

@@ -39,10 +39,16 @@ jobs:
           cp -r html_en/. $GITHUB_WORKSPACE/docs/mdns/en
           cp -r html_zh_CN/. $GITHUB_WORKSPACE/docs/mdns/zh_CN
 
+          cd $GITHUB_WORKSPACE/components/asio/docs
+          ./generate_docs
+          mkdir -p $GITHUB_WORKSPACE/docs/asio
+          cp -r html/. $GITHUB_WORKSPACE/docs/asio
+
           cd $GITHUB_WORKSPACE/docs
           touch .nojekyll
           echo '<a href="esp_modem/index.html">esp-modem</a><br>' > index.html
           echo '<a href="esp_websocket_client/index.html">esp-websocket-client</a><br>' >> index.html
+          echo '<a href="asio/index.html">ASIO</a><br>' >> index.html
           echo '<a href="mdns/en/index.html">mDNS_en</a><br>' >> index.html
           echo '<a href="mdns/zh_CN/index.html">mDNS_zh_CN</a><br>' >> index.html
 
@@ -50,7 +56,7 @@ jobs:
       - name: Upload components to component service
         uses: espressif/github-actions/upload_components@master
         with:
-          directories: "components/esp_modem;components/esp_websocket_client;components/mdns"
+          directories: "components/esp_modem;components/esp_websocket_client;components/mdns;components/asio"
           namespace: "espressif"
           api_token: ${{ secrets.IDF_COMPONENT_API_TOKEN }}
 

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "components/asio/asio"]
+	path = components/asio/asio
+	url = https://github.com/espressif/asio

README.md

@@ -19,3 +19,8 @@
 
 * Brief introduction [README](components/esp_websocket_client/README.md)
 * Full html [documentation](https://espressif.github.io/esp-protocols/esp_websocket_client/index.html)
+
+### ASIO port
+
+* Brief introduction [README](components/asio/README.md)
+* Full html [documentation](https://espressif.github.io/esp-protocols/asio/index.html)

common_components/protocol_examples_common/CMakeLists.txt

@@ -1,4 +1,4 @@
 idf_component_register(SRCS "connect.c" "stdin_out.c" "addr_from_stdin.c"
                     INCLUDE_DIRS "include"
-                    PRIV_REQUIRES esp_netif driver
+                    PRIV_REQUIRES esp_netif driver esp_eth
                     )

common_components/protocol_examples_common/include/protocol_examples_common.h

@@ -15,6 +15,7 @@ extern "C" {
 
 #include "esp_err.h"
 #include "esp_netif.h"
+#include "esp_eth.h"
 
 #ifdef CONFIG_EXAMPLE_CONNECT_ETHERNET
 #define EXAMPLE_INTERFACE get_example_netif()

components/asio/CMakeLists.txt

@@ -0,0 +1,44 @@
+if(NOT CONFIG_LWIP_IPV6 AND NOT CMAKE_BUILD_EARLY_EXPANSION)
+    # note: the component is still included in the build so it can become visible again in config
+    # without needing to re-run CMake. However no source or header files are built.
+    message(STATUS "IPV6 support is disabled so the asio component will not be built")
+    idf_component_register()
+    return()
+endif()
+
+set(asio_sources "asio/asio/src/asio.cpp")
+
+if(CONFIG_ASIO_SSL_SUPPORT)
+    if(CONFIG_ASIO_USE_ESP_OPENSSL)
+        list(APPEND asio_sources
+                "port/src/asio_ssl_impl.cpp"
+                "port/mbedtls/src/mbedtls_context.cpp"
+                "port/mbedtls/src/mbedtls_engine.cpp")
+        set(asio_priv_includes "port/mbedtls/include")
+    endif()
+
+    if(CONFIG_ASIO_USE_ESP_WOLFSSL)
+        list(APPEND asio_sources
+                "asio/asio/src/asio_ssl.cpp")
+    endif()
+endif()
+
+idf_component_register(SRCS ${asio_sources}
+                    INCLUDE_DIRS "asio/asio/include" "port/include"
+                    PRIV_INCLUDE_DIRS ${asio_priv_includes}
+                    REQUIRES lwip)
+
+if(CONFIG_ASIO_SSL_SUPPORT)
+    if(CONFIG_ASIO_USE_ESP_WOLFSSL)
+        idf_component_get_property(wolflib esp-wolfssl COMPONENT_LIB)
+        idf_component_get_property(wolfdir esp-wolfssl COMPONENT_DIR)
+
+        target_link_libraries(${COMPONENT_LIB} PUBLIC ${wolflib})
+        target_include_directories(${COMPONENT_LIB} PUBLIC ${wolfdir}/wolfssl/wolfssl)
+    endif()
+
+    if(CONFIG_ASIO_USE_ESP_OPENSSL)
+        idf_component_get_property(mbedtls mbedtls COMPONENT_LIB)
+        target_link_libraries(${COMPONENT_LIB} PUBLIC ${mbedtls})
+    endif()
+endif()

components/asio/Kconfig

@@ -0,0 +1,36 @@
+menu "ESP-ASIO"
+    visible if LWIP_IPV6
+
+    config ASIO_SSL_SUPPORT
+        bool "Enable SSL/TLS support of ASIO"
+        default n
+        help
+            Enable support for basic SSL/TLS features, available for mbedTLS/OpenSSL
+            as well as wolfSSL TLS library.
+
+    choice ASIO_SSL_LIBRARY_CHOICE
+        prompt "Choose SSL/TLS library for ESP-TLS (See help for more Info)"
+        default ASIO_USE_ESP_OPENSSL
+        depends on ASIO_SSL_SUPPORT
+        help
+            The ASIO support multiple backend TLS libraries. Currently the mbedTLS with a thin ESP-OpenSSL
+            port layer (default choice) and WolfSSL are supported.
+            Different TLS libraries may support different features and have different resource
+            usage. Consult the ESP-TLS documentation in ESP-IDF Programming guide for more details.
+        config ASIO_USE_ESP_OPENSSL
+            bool "esp-openssl"
+        config ASIO_USE_ESP_WOLFSSL
+            depends on TLS_STACK_WOLFSSL
+            bool "wolfSSL (License info in wolfSSL directory README)"
+    endchoice
+
+    config ASIO_SSL_BIO_SIZE
+        int "Size of BIO object"
+        default 1024
+        depends on ASIO_SSL_SUPPORT
+        help
+            Size in bytes of SSL-BIO implementation.
+            Reducing the BIO size saves more RAM, but may slow down input output operations due to
+            fragmentation.
+
+endmenu

components/asio/README.md

@@ -0,0 +1,11 @@
+# ASIO port
+
+Asio is a cross-platform C++ library, see https://think-async.com/Asio/. It provides a consistent asynchronous model using a modern C++ approach.
+
+## Examples
+
+Get started with example test :example:`examples <examples/..>`:
+
+## Documentation
+
+* View the full [html documentation](https://espressif.github.io/esp-protocols/asio/index.html)

components/asio/docs/Doxyfile

@@ -0,0 +1,73 @@
+# This is Doxygen configuration file
+#
+# Doxygen provides over 260 configuration statements
+# To make this file easier to follow,
+# it contains only statements that are non-default
+#
+# NOTE:
+# It is recommended not to change defaults unless specifically required
+# Test any changes how they affect generated documentation
+# Make sure that correct warnings are generated to flag issues with documented code
+#
+# For the complete list of configuration statements see:
+# http://doxygen.nl/manual/config.html
+
+
+PROJECT_NAME = "ESP Protocols Programming Guide"
+
+## The 'INPUT' statement below is used as input by script 'gen-df-input.py'
+## to automatically generate API reference list files heder_file.inc
+## These files are placed in '_inc' directory
+## and used to include in API reference documentation
+
+
+## Get warnings for functions that have no documentation for their parameters or return value
+##
+WARN_NO_PARAMDOC = YES
+
+## Enable preprocessing and remove __attribute__(...) expressions from the INPUT files
+##
+ENABLE_PREPROCESSING   = YES
+MACRO_EXPANSION        = YES
+EXPAND_ONLY_PREDEF     = YES
+PREDEFINED             = \
+    $(ENV_DOXYGEN_DEFINES) \
+    __DOXYGEN__=1 \
+    __attribute__(x)= \
+	_Static_assert()= \
+    IDF_DEPRECATED(X)= \
+    IRAM_ATTR= \
+    configSUPPORT_DYNAMIC_ALLOCATION=1 \
+    configSUPPORT_STATIC_ALLOCATION=1 \
+    configQUEUE_REGISTRY_SIZE=1 \
+    configUSE_RECURSIVE_MUTEXES=1 \
+    configTHREAD_LOCAL_STORAGE_DELETE_CALLBACKS=1 \
+    configNUM_THREAD_LOCAL_STORAGE_POINTERS=1 \
+    configUSE_APPLICATION_TASK_TAG=1 \
+    configTASKLIST_INCLUDE_COREID=1 \
+    "ESP_EVENT_DECLARE_BASE(x)=extern esp_event_base_t x"
+
+## Do not complain about not having dot
+##
+HAVE_DOT = NO
+
+## Generate XML that is required for Breathe
+##
+GENERATE_XML    = YES
+XML_OUTPUT      = xml
+
+GENERATE_HTML   = NO
+HAVE_DOT        = NO
+GENERATE_LATEX  = NO
+GENERATE_MAN    = YES
+GENERATE_RTF    = NO
+
+## Skip distracting progress messages
+##
+QUIET = YES
+
+## Enable Section Tags for conditional documentation
+##
+ENABLED_SECTIONS += \
+    DOC_EXCLUDE_HEADER_SECTION \   ## To conditionally remove doc sections from IDF source files without affecting documentation in upstream files.
+    DOC_SINGLE_GROUP        ## To conditionally remove groups from the documentation and create a 'flat' document without affecting documentation in upstream files.

components/asio/docs/conf_common.py

@@ -0,0 +1,21 @@
+from esp_docs.conf_docs import *  # noqa: F403,F401
+
+extensions += ['sphinx_copybutton',
+               # Needed as a trigger for running doxygen
+               'esp_docs.esp_extensions.dummy_build_system',
+               'esp_docs.esp_extensions.run_doxygen',
+               ]
+
+# link roles config
+github_repo = 'espressif/esp-protocols'
+
+# context used by sphinx_idf_theme
+html_context['github_user'] = 'espressif'
+html_context['github_repo'] = 'esp-protocols'
+
+# Extra options required by sphinx_idf_theme
+project_slug = 'esp-idf' # >=5.0
+versions_url = 'https://github.com/espressif/esp-protocols/docs/docs_versions.js'
+
+idf_targets = ['esp32']
+languages = ['en', 'zh_CN']

components/asio/docs/en/conf.py

@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+#
+# English Language RTD & Sphinx config file
+#
+# Uses ../conf_common.py for most non-language-specific settings.
+
+# Importing conf_common adds all the non-language-specific
+# parts to this conf module
+
+try:
+    from conf_common import *  # noqa: F403,F401
+except ImportError:
+    import os
+    import sys
+    sys.path.insert(0, os.path.abspath('../'))
+    from conf_common import *  # noqa: F403,F401
+
+# General information about the project.
+project = u'ESP-Protocols'
+copyright = u'2016 - 2022, Espressif Systems (Shanghai) Co., Ltd'
+
+# The language for content autogenerated by Sphinx. Refer to documentation
+# for a list of supported languages.
+language = 'en'

components/asio/docs/en/index.rst

@@ -0,0 +1,42 @@
+ASIO port
+=========
+
+Overview
+--------
+Asio is a cross-platform C++ library, see https://think-async.com/Asio/. It provides a consistent asynchronous model using a modern C++ approach.
+
+
+ASIO documentation
+^^^^^^^^^^^^^^^^^^
+Please refer to the original asio documentation at https://think-async.com/Asio/Documentation.
+Asio also comes with a number of examples which could be find under Documentation/Examples on that web site.
+
+Supported features
+^^^^^^^^^^^^^^^^^^
+ESP platform port currently supports only network asynchronous socket operations; does not support serial port.
+SSL/TLS support is disabled by default and could be enabled in component configuration menu by choosing TLS library from
+
+- mbedTLS with OpenSSL translation layer (default option)
+- wolfSSL
+
+SSL support is very basic at this stage and it does include following features:
+
+- Verification callbacks
+- DH property files
+- Certificates/private keys file APIs
+
+Internal asio settings for ESP include
+
+- EXCEPTIONS are enabled in ASIO if enabled in menuconfig
+- TYPEID is enabled in ASIO if enabled in menuconfig
+
+Application Example
+-------------------
+ESP examples are based on standard asio :example:`examples <../examples>`:
+
+- :example:`udp_echo_server <../examples/udp_echo_server>`
+- :example:`tcp_echo_server <../examples/tcp_echo_server>`
+- :example:`asio_chat <../examples/asio_chat>`
+- :example:`ssl_client_server <../examples/ssl_client_server>`
+
+Please refer to the specific example README.md for details

components/asio/docs/generate_docs

@@ -0,0 +1,27 @@
+build-docs --target esp32 --language en
+
+cp -rf _build/en/esp32/html .
+rm -rf _build __pycache__
+
+# Modifes some version and target fields of index.html
+echo "<script type="text/javascript">
+window.onload =(function() {
+    var myAnchor = document.getElementById('version-select');
+    var mySpan = document.createElement('input');
+    mySpan.setAttribute('type', 'text');
+    mySpan.setAttribute('maxLength', '10');
+    mySpan.value = 'latest';
+    mySpan.setAttribute('disabled', true);
+    myAnchor.parentNode.replaceChild(mySpan, myAnchor);
+ 
+    var myAnchor = document.getElementById('target-select');
+    var mySpan = document.createElement('input');
+    mySpan.setAttribute('type', 'text');
+    mySpan.setAttribute('maxLength', '10');
+    mySpan.value = 'all targets';
+    mySpan.setAttribute('disabled', true);
+    myAnchor.parentNode.replaceChild(mySpan, myAnchor);
+
+})();
+</script>" >> html/index.html
+

components/asio/docs/zh_CN/conf.py

@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+#
+# English Language RTD & Sphinx config file
+#
+# Uses ../conf_common.py for most non-language-specific settings.
+
+# Importing conf_common adds all the non-language-specific
+# parts to this conf module
+try:
+    from conf_common import *  # noqa: F403,F401
+except ImportError:
+    import os
+    import sys
+    sys.path.insert(0, os.path.abspath('..'))
+    from conf_common import *  # noqa: F403,F401
+
+import datetime
+
+current_year = datetime.datetime.now().year
+
+# General information about the project.
+project = u'ESP-IDF 编程指南'
+copyright = u'2016 - {} 乐鑫信息科技（上海）股份有限公司'.format(current_year)
+
+# The language for content autogenerated by Sphinx. Refer to documentation
+# for a list of supported languages.
+language = 'zh_CN'

components/asio/docs/zh_CN/index.rst

@@ -0,0 +1 @@
+.. include:: ../../../en/api-reference/protocols/asio.rst

components/asio/examples/asio_chat/CMakeLists.txt

@@ -0,0 +1,10 @@
+# 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 3.16)
+
+# (Not part of the boilerplate)
+# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
+set(EXTRA_COMPONENT_DIRS ../../../../common_components/protocol_examples_common)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(asio_chat)

components/asio/examples/asio_chat/README.md

@@ -0,0 +1,65 @@
+| Supported Targets | ESP32 | ESP32-S2 | ESP32-S3 | ESP32-C3 |
+| ----------------- | ----- | -------- | -------- | -------- |
+
+
+# Asio chat client and server examples
+
+(See the README.md file in the upper level 'examples' directory for more information about examples.)
+
+The application aims to demonstrate a simple use of Asio library in different modes.
+In project settings it could be configured to run either a Asio chat server, a Asio chat client, or both.
+
+## How to use example
+
+The example is configured by default as an Asio chat client.
+
+Note that the example uses string representation of IP addresses and ports.
+
+You can find the upstream asio chat implementation [here] https://github.com/chriskohlhoff/asio/tree/master/asio/src/examples/cpp11/chat
+
+### Asio Client
+
+In the client mode, the example connects to the configured address, sends the message, which was inserted as an input in the terminal, and receives a response.
+
+### Asio Server
+
+In the server mode, Asio chat server with a specified port number is created and being polled till a connection request from the client arrives.
+Chat server echoes a message (received from any client) to all connected clients.
+
+## Configure the project
+
+```
+idf.py menuconfig
+```
+
+Set following parameters under Example Configuration Options:
+
+* Set `EXAMPLE_CHAT_SERVER` to use the example as an ASIO chat server
+    * Configure `EXAMPLE_CHAT_SERVER_BIND_PORT` to the port number.
+
+* Set `EXAMPLE_CHAT_CLIENT` to use the example as an ASIO chat client
+    * Configure `EXAMPLE_CHAT_CLIENT_CONNECT_ADDRESS` to a string representation of the address to connect the client to.
+    * Configure `EXAMPLE_CHAT_CLIENT_CONNECT_PORT` to the port number.
+
+* Configure Wi-Fi or Ethernet under "Example Connection Configuration" menu. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../../README.md) for more d    etails.
+
+## Running the example in server mode
+
+- Configure the example according "Configure the project" section.
+- Run `idf.py -p PORT flash monitor` to build and upload the example to your board and connect to it's serial terminal.
+- Wait for the board to connect to WiFi or Ethernet (note the IP address).
+- Connect to the server using multiple clients, for example using any option below.
+    - build and run asio chat client on your host machine
+    - run chat_client asio example on ESP platform
+    - since chat messages consists of ASCII size and message, it is possible to
+        netcat `nc IP PORT` and type for example ` 4ABC<CR>` to transmit 'ABC\n'
+
+## Running the example in client mode
+
+- Configure the example according "Configure the project" section.
+- Start chat server either on host machine or as another ESP device running chat_server example.
+- Run `idf.py -p PORT flash monitor` to build and upload the example to your board and connect to it's serial terminal.
+- Wait for the board to connect to WiFi or Ethernet.
+- Receive and send messages to/from other clients on stdin/stdout via serial terminal.
+
+See the README.md file in the upper level 'examples' directory for more information about examples.

components/asio/examples/asio_chat/example_test.py

@@ -0,0 +1,29 @@
+# This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+# Unless required by applicable law or agreed to in writing, this
+# software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+# CONDITIONS OF ANY KIND, either express or implied.
+
+# -*- coding: utf-8 -*-
+
+from __future__ import print_function, unicode_literals
+
+import re
+
+import ttfw_idf
+
+
+@ttfw_idf.idf_example_test(env_tag='Example_GENERIC')
+def test_examples_asio_chat(env, _):  # type: (ttfw_idf.TinyFW.Env, None) -> None
+    msg = 'asio-chat: received hi'
+    dut = env.get_dut('asio_chat', 'examples/protocols/asio/asio_chat')
+    # start the test and expect the client to receive back it's original data
+    dut.start_app()
+    dut.expect(re.compile(r'{}'.format('Waiting for input')), timeout=30)
+    dut.write(msg)
+    dut.write('exit')
+    dut.expect(re.compile(r'{}'.format(msg)), timeout=30)
+
+
+if __name__ == '__main__':
+    test_examples_asio_chat()

components/asio/examples/asio_chat/main/CMakeLists.txt

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

components/asio/examples/asio_chat/main/Kconfig.projbuild

@@ -0,0 +1,39 @@
+menu "Example Configuration"
+
+    config EXAMPLE_CHAT_SERVER
+        bool "Asio example chat server"
+        default n
+        help
+            This example will setup a chat server, binds it to the specified address
+            and starts listening.
+
+    if EXAMPLE_CHAT_SERVER
+        config EXAMPLE_CHAT_SERVER_BIND_PORT
+            string "Asio example server bind port"
+            default "3344"
+            help
+                Server listener's socket would be bound to this port.
+    endif
+
+    config EXAMPLE_CHAT_CLIENT
+        bool "Asio example chat client"
+        default y
+        help
+            This example will setup an asio chat client.
+            and sends the data.
+
+    if EXAMPLE_CHAT_CLIENT
+        config EXAMPLE_CHAT_CLIENT_CONNECT_ADDRESS
+            string "Client connection address"
+            default "192.168.0.1"
+            help
+                Client's socket would connect to this address/host.
+
+        config EXAMPLE_CHAT_CLIENT_CONNECT_PORT
+            string "Client connection port"
+            default "3344"
+            help
+                Client's connection port.
+    endif
+
+endmenu

components/asio/examples/asio_chat/main/asio_chat.cpp

@@ -0,0 +1,119 @@
+/* ASIO chat server client example
+
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+*/
+
+#include "protocol_examples_common.h"
+#include "esp_log.h"
+#include "esp_event.h"
+#include "nvs_flash.h"
+#include "server.hpp"
+#include "client.hpp"
+#include <thread>
+#include <pthread.h>
+
+using asio::ip::tcp;
+
+static const char *TAG = "asio-chat";
+
+// This variable is necessary for `python test` execution, it provides synchronisation between server/client(as server should be started before client)
+std::mutex server_ready;
+
+#ifdef CONFIG_EXAMPLE_CHAT_CLIENT
+static void get_string(char *line, size_t size)
+{
+    int count = 0;
+    while (count < size) {
+        int c = fgetc(stdin);
+        if (c == '\n') {
+            line[count] = '\0';
+            break;
+        } else if (c > 0 && c < 127) {
+            line[count] = c;
+            ++count;
+        }
+        vTaskDelay(10 / portTICK_PERIOD_MS);
+    }
+}
+
+void start_client(void)
+{
+    const std::string port(CONFIG_EXAMPLE_CHAT_CLIENT_CONNECT_PORT);
+    const std::string name(CONFIG_EXAMPLE_CHAT_CLIENT_CONNECT_ADDRESS);
+    asio::io_context io_context;
+    char line[128];
+
+    tcp::resolver resolver(io_context);
+    auto endpoints = resolver.resolve(name, port);
+    chat_client c(io_context, endpoints);
+#ifdef CONFIG_EXAMPLE_CHAT_SERVER
+    std::lock_guard<std::mutex> guard(server_ready);
+#endif
+    std::thread t([&io_context]() { try {
+                                        io_context.run();
+                                  } catch (const std::exception &e) {
+                                        ESP_LOGE(TAG, "Exception occured during client thread execution %s", e.what());
+                                  }
+                                    catch (...) {
+                                         ESP_LOGE(TAG, "Unknown exception");
+                                   }});
+    do {
+        ESP_LOGI(TAG, "CLIENT: Waiting for input");
+        get_string(line, sizeof(line));
+
+        chat_message msg;
+        msg.body_length(std::strlen(line));
+        std::memcpy(msg.body(), line, msg.body_length());
+        msg.encode_header();
+        c.write(msg);
+        sleep(1);
+    } while (strcmp(line, "exit") != 0);
+
+    c.close();
+    t.join();
+}
+#endif // CONFIG_EXAMPLE_CHAT_CLIENT
+
+extern "C" void app_main(void)
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+    esp_netif_init();
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+
+    try {
+#ifdef CONFIG_EXAMPLE_CHAT_SERVER
+        asio::io_context io_context;
+        chat_server server(io_context, tcp::endpoint(tcp::v4(), std::atoi(CONFIG_EXAMPLE_CHAT_SERVER_BIND_PORT)));
+        std::thread t =  std::thread([&io_context]() { // Chat server starting here
+                                     try {
+                                           io_context.run();
+                                     } catch (const std::exception &e) {
+                                           ESP_LOGE(TAG, "Exception occured during server thread execution %s", e.what());
+                                     }
+                                       catch (...) {
+                                           ESP_LOGE(TAG, "Unknown exception");
+                                     }});;
+#endif
+#ifdef CONFIG_EXAMPLE_CHAT_CLIENT
+        start_client();
+#endif
+#ifdef CONFIG_EXAMPLE_CHAT_SERVER
+        t.join();
+#endif
+    } catch (const std::exception &e) {
+        ESP_LOGE(TAG, "Exception occured during run %s", e.what());
+    } catch (...) {
+        ESP_LOGE(TAG, "Unknown exception");
+    }
+    ESP_ERROR_CHECK(example_disconnect());
+}

components/asio/examples/asio_chat/main/chat_message.hpp

@@ -0,0 +1,91 @@
+//
+// chat_message.hpp
+// ~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2018 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef CHAT_MESSAGE_HPP
+#define CHAT_MESSAGE_HPP
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+class chat_message
+{
+public:
+  static constexpr std::size_t header_length = 4;
+  static constexpr std::size_t max_body_length = 512;
+
+  chat_message()
+    : body_length_(0)
+  {
+  }
+
+  const char* data() const
+  {
+    return data_;
+  }
+
+  char* data()
+  {
+    return data_;
+  }
+
+  std::size_t length() const
+  {
+    return header_length + body_length_;
+  }
+
+  const char* body() const
+  {
+    return data_ + header_length;
+  }
+
+  char* body()
+  {
+    return data_ + header_length;
+  }
+
+  std::size_t body_length() const
+  {
+    return body_length_;
+  }
+
+  void body_length(std::size_t new_length)
+  {
+    body_length_ = new_length;
+    if (body_length_ > max_body_length)
+      body_length_ = max_body_length;
+  }
+
+  bool decode_header()
+  {
+    char header[header_length + 1] = "";
+    std::strncat(header, data_, header_length);
+    body_length_ = std::atoi(header);
+    if (body_length_ > max_body_length)
+    {
+      body_length_ = 0;
+      return false;
+    }
+    return true;
+  }
+
+  void encode_header()
+  {
+    char header[header_length + 1] = "";
+    std::sprintf(header, "%4d", static_cast<int>(body_length_));
+    std::memcpy(data_, header, header_length);
+  }
+
+private:
+  char data_[header_length + max_body_length];
+  std::size_t body_length_;
+};
+
+#endif // CHAT_MESSAGE_HPP

components/asio/examples/asio_chat/main/client.hpp

@@ -0,0 +1,126 @@
+//
+// client.hpp
+// ~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2018 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef CHAT_CLIENT_HPP
+#define CHAT_CLIENT_HPP
+
+#include <deque>
+#include "asio.hpp"
+#include "chat_message.hpp"
+
+typedef std::deque<chat_message> chat_message_queue;
+
+class chat_client
+{
+public:
+  chat_client(asio::io_context& io_context,
+      const asio::ip::tcp::resolver::results_type& endpoints)
+    : io_context_(io_context),
+      socket_(io_context)
+  {
+    do_connect(endpoints);
+  }
+
+  void write(const chat_message& msg)
+  {
+    asio::post(io_context_,
+        [this, msg]()
+        {
+          bool write_in_progress = !write_msgs_.empty();
+          write_msgs_.push_back(msg);
+          if (!write_in_progress)
+          {
+            do_write();
+          }
+        });
+  }
+
+  void close()
+  {
+    asio::post(io_context_, [this]() { socket_.close(); });
+  }
+
+private:
+void do_connect(const asio::ip::tcp::resolver::results_type& endpoints)
+    {
+      asio::async_connect(socket_, endpoints,
+          [this](std::error_code ec, asio::ip::tcp::endpoint)
+          {
+            if (!ec)
+            {
+              do_read_header();
+            }
+          });
+    }
+
+    void do_read_header()
+    {
+      asio::async_read(socket_,
+          asio::buffer(read_msg_.data(), chat_message::header_length),
+          [this](std::error_code ec, std::size_t /*length*/)
+          {
+            if (!ec && read_msg_.decode_header())
+            {
+              do_read_body();
+            }
+            else
+            {
+              socket_.close();
+            }
+          });
+    }
+
+    void do_read_body()
+    {
+      asio::async_read(socket_,
+          asio::buffer(read_msg_.body(), read_msg_.body_length()),
+          [this](std::error_code ec, std::size_t /*length*/)
+          {
+            if (!ec)
+            {
+              do_read_header();
+            }
+            else
+            {
+              socket_.close();
+            }
+          });
+    }
+
+     void do_write()
+     {
+      asio::async_write(socket_,
+          asio::buffer(write_msgs_.front().data(),
+            write_msgs_.front().length()),
+          [this](std::error_code ec, std::size_t /*length*/)
+          {
+            if (!ec)
+            {
+              write_msgs_.pop_front();
+              if (!write_msgs_.empty())
+              {
+                do_write();
+              }
+            }
+            else
+            {
+              socket_.close();
+            }
+          });
+      }
+
+private:
+    asio::io_context& io_context_;
+    asio::ip::tcp::socket socket_;
+    chat_message read_msg_;
+    chat_message_queue write_msgs_;
+};
+
+#endif // CHAT_CLIENT_HPP

components/asio/examples/asio_chat/main/server.hpp

@@ -0,0 +1,202 @@
+//
+// server.hpp
+// ~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2018 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef CHAT_SERVER_HPP
+#define CHAT_SERVER_HPP
+
+#include <list>
+#include <set>
+#include <deque>
+#include <utility>
+#include "asio.hpp"
+#include "chat_message.hpp"
+
+//----------------------------------------------------------------------
+
+typedef std::deque<chat_message> chat_message_queue;
+
+extern std::mutex server_ready;
+
+//----------------------------------------------------------------------
+
+
+class chat_participant
+{
+public:
+  virtual ~chat_participant() {}
+  virtual void deliver(const chat_message& msg) = 0;
+};
+
+typedef std::shared_ptr<chat_participant> chat_participant_ptr;
+
+//----------------------------------------------------------------------
+
+class chat_room
+{
+public:
+  void join(chat_participant_ptr participant)
+  {
+    participants_.insert(participant);
+    for (auto msg: recent_msgs_)
+      participant->deliver(msg);
+  }
+
+  void leave(chat_participant_ptr participant)
+  {
+    participants_.erase(participant);
+  }
+
+  void deliver(const chat_message& msg)
+  {
+    recent_msgs_.push_back(msg);
+    while (recent_msgs_.size() > max_recent_msgs)
+      recent_msgs_.pop_front();
+
+    for (auto participant: participants_)
+      participant->deliver(msg);
+  }
+
+private:
+  std::set<chat_participant_ptr> participants_;
+  enum { max_recent_msgs = 100 };
+  chat_message_queue recent_msgs_;
+};
+
+//----------------------------------------------------------------------
+
+
+class chat_session
+  : public chat_participant,
+    public std::enable_shared_from_this<chat_session>
+{
+public:
+  chat_session(asio::ip::tcp::socket socket, chat_room& room)
+    : socket_(std::move(socket)),
+      room_(room)
+  {
+  }
+
+  void start()
+  {
+    room_.join(shared_from_this());
+    do_read_header();
+  }
+
+  void deliver(const chat_message& msg)
+  {
+    bool write_in_progress = !write_msgs_.empty();
+    write_msgs_.push_back(msg);
+    if (!write_in_progress)
+    {
+      do_write();
+    }
+  }
+
+private:
+  void do_read_header()
+  {
+    auto self(shared_from_this());
+    asio::async_read(socket_,
+        asio::buffer(read_msg_.data(), chat_message::header_length),
+        [this, self](std::error_code ec, std::size_t /*length*/)
+        {
+          if (!ec && read_msg_.decode_header())
+          {
+            do_read_body();
+          }
+          else
+          {
+            room_.leave(shared_from_this());
+          }
+         });
+   }
+
+   void do_read_body()
+   {
+     auto self(shared_from_this());
+     asio::async_read(socket_,
+         asio::buffer(read_msg_.body(), read_msg_.body_length()),
+         [this, self](std::error_code ec, std::size_t /*length*/)
+         {
+           if (!ec)
+           {
+             ESP_LOGD("asio-chat:", "%s", read_msg_.body());
+             room_.deliver(read_msg_);
+             do_read_header();
+           }
+           else
+           {
+             room_.leave(shared_from_this());
+           }
+         });
+   }
+
+   void do_write()
+   {
+     auto self(shared_from_this());
+     asio::async_write(socket_,
+         asio::buffer(write_msgs_.front().data(),
+           write_msgs_.front().length()),
+         [this, self](std::error_code ec, std::size_t /*length*/)
+         {
+           if (!ec)
+           {
+             write_msgs_.pop_front();
+             if (!write_msgs_.empty())
+             {
+               do_write();
+             }
+           }
+           else
+           {
+             room_.leave(shared_from_this());
+           }
+         });
+   }
+
+   asio::ip::tcp::socket socket_;
+   chat_room& room_;
+   chat_message read_msg_;
+   chat_message_queue write_msgs_;
+ };
+
+//----------------------------------------------------------------------
+
+class chat_server
+{
+public:
+  chat_server(asio::io_context& io_context,
+      const asio::ip::tcp::endpoint& endpoint)
+    : acceptor_(io_context, endpoint)
+  {
+    do_accept();
+  }
+
+private:
+  void do_accept()
+  {
+    std::lock_guard<std::mutex> guard(server_ready);
+    acceptor_.async_accept(
+       [this](std::error_code ec, asio::ip::tcp::socket socket)
+       {
+         if (!ec)
+         {
+           std::make_shared<chat_session>(std::move(socket), room_)->start();
+         }
+
+         do_accept();
+       });
+  }
+
+  asio::ip::tcp::acceptor acceptor_;
+  chat_room room_;
+};
+
+#endif // CHAT_SERVER_HPP

components/asio/examples/asio_chat/sdkconfig.ci

@@ -0,0 +1,6 @@
+CONFIG_EXAMPLE_CONNECT_WIFI=n
+CONFIG_EXAMPLE_CONNECT_ETHERNET=n
+CONFIG_EXAMPLE_CHAT_CLIENT=y
+CONFIG_EXAMPLE_CHAT_SERVER=y
+CONFIG_LOG_DEFAULT_LEVEL_DEBUG=y
+CONFIG_EXAMPLE_CHAT_CLIENT_CONNECT_ADDRESS="localhost"

components/asio/examples/asio_chat/sdkconfig.defaults

@@ -0,0 +1,2 @@
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
+CONFIG_COMPILER_CXX_EXCEPTIONS=y

components/asio/examples/async_request/CMakeLists.txt

@@ -0,0 +1,10 @@
+# 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 3.16)
+
+# (Not part of the boilerplate)
+# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
+set(EXTRA_COMPONENT_DIRS ../../../../common_components/protocol_examples_common)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(async_http_request)

components/asio/examples/async_request/README.md

@@ -0,0 +1,52 @@
+| Supported Targets | ESP32 |
+| ----------------- | ----- |
+
+# Async request using ASIO
+
+(See the README.md file in the upper level 'examples' directory for more information about examples.)
+
+The application aims to show how to compose async operations using ASIO to build network protocols and operations.
+
+# Configure and Building example
+
+This example doesn't require any configuration, just build it with 
+
+```
+idf.py build
+```
+
+# Async operations composition and automatic lifetime control
+
+On this example we compose the operation by starting the next step in the chain inside the completion handler of the 
+previous operation. Also we pass the `Connection` class itself as the parameter of its final handler to be owned by 
+the following operation. This is possible due to the control of lifetime by the usage of `std::shared_ptr`.
+
+The control of lifetime of the class, done by `std::shared_ptr` usage, guarantee that the data will be available for 
+async operations until it's not needed any more. This makes necessary that all of the async operation class must start 
+its lifetime as a `std::shared_ptr` due to the usage of `std::enable_shared_from_this`.
+
+
+     User creates a shared_ptr──┐
+     of AddressResolution and   │
+     ask for resolve.           │
+     The handler for the       ┌▼─────────────────────┐
+     complete operation is sent│   AddressResolution  │  In the completion of resolve a connection is created.
+                               └─────────────────┬────┘  AddressResolution is automaticly destroyed since it's
+                                                 │       no longer needed
+                                               ┌─▼────────────────────────────────────┐
+                                               │         Connection                   │
+                                               └──────┬───────────────────────────────┘
+  Http::Session is created once we have a Connection. │
+  Connection is passed to Http::Session that holds it │
+  avoiding it's destruction.                          │
+                                                    ┌─▼───────────────────────────────┐
+                                                    │       Http::Session             │
+                                                    └────────┬────────────────────────┘
+                                After the HTTP request is    │
+                                sent the completion handler  │
+                                is called.                   │
+                                                             └────►Completion Handler()
+
+
+The previous diagram shows the process and the life span of each of the tasks in this examples. At each stage the 
+object responsible for the last action inject itself to the completion handler of the next stage for reuse.

components/asio/examples/async_request/main/CMakeLists.txt

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

components/asio/examples/async_request/main/async_http_request.cpp

@@ -0,0 +1,369 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: CC0-1.0
+ *
+ *  ASIO HTTP request example
+*/
+
+#include <string>
+#include <array>
+#include <asio.hpp>
+#include <memory>
+#include <system_error>
+#include <utility>
+#include "esp_log.h"
+#include "nvs_flash.h"
+#include "esp_event.h"
+#include "protocol_examples_common.h"
+
+constexpr auto TAG = "async_request";
+using asio::ip::tcp;
+
+namespace {
+
+void esp_init()
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+    esp_log_level_set("async_request", ESP_LOG_DEBUG);
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+}
+
+/**
+ * @brief Simple class to add the resolver to a chain of actions
+ *
+ */
+class AddressResolution : public std::enable_shared_from_this<AddressResolution> {
+public:
+    explicit AddressResolution(asio::io_context &context) : ctx(context), resolver(ctx) {}
+
+    /**
+     * @brief Initiator function for the address resolution
+     *
+     * @tparam CompletionToken callable responsible to use the results.
+     *
+     * @param host Host address
+     * @param port Port for the target, must be number due to a limitation on lwip.
+     */
+    template<class CompletionToken>
+    void resolve(const std::string &host, const std::string &port, CompletionToken &&completion_handler)
+    {
+        auto self(shared_from_this());
+        resolver.async_resolve(host, port, [self, completion_handler](const asio::error_code & error, tcp::resolver::results_type results) {
+            if (error) {
+                ESP_LOGE(TAG, "Failed to resolve: %s", error.message().c_str());
+                return;
+            }
+            completion_handler(self, results);
+        });
+    }
+
+private:
+    asio::io_context &ctx;
+    tcp::resolver resolver;
+
+};
+
+/**
+ * @brief Connection class
+ *
+ * The lowest level dependency on our asynchronous task, Connection provide an interface to TCP sockets.
+ * A similar class could be provided for a TLS connection.
+ *
+ * @note: All read and write operations are written on an explicit strand, even though an implicit strand
+ * occurs in this example since we run the io context in a single task.
+ *
+ */
+class Connection : public std::enable_shared_from_this<Connection> {
+public:
+    explicit Connection(asio::io_context &context) : ctx(context), strand(context), socket(ctx) {}
+
+    /**
+     * @brief Start the connection
+     *
+     * Async operation to start a connection. As the final act of the process the Connection class pass a
+     * std::shared_ptr of itself to the completion_handler.
+     * Since it uses std::shared_ptr as an automatic control of its lifetime this class must be created
+     * through a std::make_shared call.
+     *
+     * @tparam completion_handler A callable to act as the final handler for the process.
+     * @param host host address
+     * @param port port number - due to a limitation on lwip implementation this should be the number not the
+     *                           service name typically seen in ASIO examples.
+     *
+     * @note The class could be modified to store the completion handler, as a member variable, instead of
+     * pass it along asynchronous calls to allow the process to run again completely.
+     *
+     */
+    template<class CompletionToken>
+    void start(tcp::resolver::results_type results, CompletionToken &&completion_handler)
+    {
+        connect(results, completion_handler);
+    }
+
+    /**
+     * @brief Start an async write on the socket
+     *
+     * @tparam data
+     * @tparam completion_handler A callable to act as the final handler for the process.
+     *
+     */
+    template<class DataType, class CompletionToken>
+    void write_async(const DataType &data, CompletionToken &&completion_handler)
+    {
+        asio::async_write(socket, data, asio::bind_executor(strand, completion_handler));
+    }
+
+    /**
+     * @brief Start an async read on the socket
+     *
+     * @tparam data
+     * @tparam completion_handler A callable to act as the final handler for the process.
+     *
+     */
+    template<class DataBuffer, class CompletionToken>
+    void read_async(DataBuffer &&in_data, CompletionToken &&completion_handler)
+    {
+        asio::async_read(socket, in_data, asio::bind_executor(strand, completion_handler));
+    }
+
+private:
+
+    template<class CompletionToken>
+    void connect(tcp::resolver::results_type results, CompletionToken &&completion_handler)
+    {
+        auto self(shared_from_this());
+        asio::async_connect(socket, results, [self, completion_handler](const asio::error_code & error, [[maybe_unused]] const tcp::endpoint & endpoint) {
+            if (error) {
+                ESP_LOGE(TAG, "Failed to connect: %s", error.message().c_str());
+                return;
+            }
+            completion_handler(self);
+        });
+    }
+    asio::io_context &ctx;
+    asio::io_context::strand strand;
+    tcp::socket socket;
+};
+
+}  // namespace
+namespace Http {
+enum class Method { GET };
+
+/**
+ * @brief Simple HTTP request class
+ *
+ * The user needs to write the request information direct to header and body fields.
+ *
+ * Only GET verb is provided.
+ *
+ */
+class Request {
+public:
+    Request(Method method, std::string host, std::string port, const std::string &target) : host_data(std::move(host)), port_data(std::move(port))
+    {
+        header_data.append("GET ");
+        header_data.append(target);
+        header_data.append(" HTTP/1.1");
+        header_data.append("\r\n");
+        header_data.append("Host: ");
+        header_data.append(host_data);
+        header_data.append("\r\n");
+        header_data.append("\r\n");
+    };
+
+    void set_header_field(std::string const &field)
+    {
+        header_data.append(field);
+    }
+
+    void append_to_body(std::string const &data)
+    {
+        body_data.append(data);
+    };
+
+    const std::string &host() const
+    {
+        return host_data;
+    }
+
+    const std::string &service_port() const
+    {
+        return port_data;
+    }
+
+    const std::string &header() const
+    {
+        return header_data;
+    }
+
+    const std::string &body() const
+    {
+        return body_data;
+    }
+
+private:
+    std::string host_data;
+    std::string port_data;
+    std::string header_data;
+    std::string body_data;
+};
+
+/**
+ * @brief Simple HTTP response class
+ *
+ * The response is built from received data and only parsed to split header and body.
+ *
+ * A copy of the received data is kept.
+ *
+ */
+struct Response {
+    /**
+     * @brief Construct a response from a contiguous buffer.
+     *
+     * Simple http parsing.
+     *
+     */
+    template<class DataIt>
+    explicit Response(DataIt data, size_t size)
+    {
+        raw_response = std::string(data, size);
+
+        auto header_last = raw_response.find("\r\n\r\n");
+        if (header_last != std::string::npos) {
+            header = raw_response.substr(0, header_last);
+        }
+        body = raw_response.substr(header_last + 3);
+    }
+    /**
+     * @brief Print response content.
+     */
+    void print()
+    {
+        ESP_LOGI(TAG, "Header :\n %s", header.c_str());
+        ESP_LOGI(TAG, "Body : \n %s", body.c_str());
+    }
+
+    std::string raw_response;
+    std::string header;
+    std::string body;
+};
+
+/** @brief HTTP Session
+ *
+ * Session class to handle HTTP protocol implementation.
+ *
+ */
+class Session : public std::enable_shared_from_this<Session> {
+public:
+    explicit Session(std::shared_ptr<Connection> connection_in) : connection(std::move(connection_in))
+    {
+    }
+
+    template<class CompletionToken>
+    void send_request(const Request &request, CompletionToken &&completion_handler)
+    {
+        auto self = shared_from_this();
+        send_data = { asio::buffer(request.header()), asio::buffer(request.body()) };
+        connection->write_async(send_data, [self, &completion_handler](std::error_code error, std::size_t bytes_transfered) {
+            if (error) {
+                ESP_LOGE(TAG, "Request write error: %s", error.message().c_str());
+                return;
+            }
+            ESP_LOGD(TAG, "Bytes Transfered: %d", bytes_transfered);
+            self->get_response(completion_handler);
+        });
+    }
+
+private:
+    template<class CompletionToken>
+    void get_response(CompletionToken &&completion_handler)
+    {
+        auto self = shared_from_this();
+        connection->read_async(asio::buffer(receive_buffer), [self, &completion_handler](std::error_code error, std::size_t bytes_received) {
+            if (error and error.value() != asio::error::eof) {
+                return;
+            }
+            ESP_LOGD(TAG, "Bytes Received: %d", bytes_received);
+            if (bytes_received == 0) {
+                return;
+            }
+            Response response(std::begin(self->receive_buffer), bytes_received);
+
+            completion_handler(self, response);
+        });
+    }
+    /*
+     * For this example we assumed 2048 to be enough for the receive_buffer
+     */
+    std::array<char, 2048> receive_buffer;
+    /*
+     * The hardcoded 2 below is related to the type we receive the data to send. We gather the parts from Request, header
+     * and body, to send avoiding the copy.
+     */
+    std::array<asio::const_buffer, 2> send_data;
+    std::shared_ptr<Connection> connection;
+};
+
+/** @brief Execute a fully async HTTP request
+ *
+ * @tparam completion_handler
+ * @param  ctx io context
+ * @param  request
+ *
+ * @note :  We build this function as a simpler interface to compose the operations of connecting to
+ *          the address and running the HTTP session. The Http::Session class is injected to the completion handler
+ *          for further use.
+ */
+template<class CompletionToken>
+void request_async(asio::io_context &context, const Request &request, CompletionToken &&completion_handler)
+{
+    /*
+     * The first step is to resolve the address we want to connect to.
+     * The AddressResolution itself is injected to the completion handler.
+     *
+     * This shared_ptr is destroyed by the end of the scope. Pay attention that this is a non blocking function
+     * the lifetime of the object is extended by the resolve call
+     */
+    std::make_shared<AddressResolution>(context)->resolve(request.host(), request.service_port(),
+    [&context, &request, completion_handler](std::shared_ptr<AddressResolution> resolver, tcp::resolver::results_type results) {
+        /* After resolution we create a Connection.
+        *  The completion handler gets a shared_ptr<Connection> to receive the connection, once the
+        *  connection process is complete.
+        */
+        std::make_shared<Connection>(context)->start(results,
+        [&request, completion_handler](std::shared_ptr<Connection> connection) {
+            // Now we create a HTTP::Session and inject the necessary connection.
+            std::make_shared<Session>(connection)->send_request(request, completion_handler);
+        });
+    });
+}
+}// namespace Http
+
+extern "C" void app_main(void)
+{
+    // Basic initialization of ESP system
+    esp_init();
+
+    asio::io_context io_context;
+    Http::Request request(Http::Method::GET, "www.httpbin.org", "80", "/get");
+    Http::request_async(io_context, request, [](std::shared_ptr<Http::Session> session, Http::Response response) {
+        /*
+         * We only print the response here but could reuse session for other requests.
+         */
+        response.print();
+    });
+
+    // io_context.run will block until all the tasks on the context are done.
+    io_context.run();
+    ESP_LOGI(TAG, "Context run done");
+
+    ESP_ERROR_CHECK(example_disconnect());
+}

components/asio/examples/socks4/CMakeLists.txt

@@ -0,0 +1,10 @@
+# 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 3.16)
+
+# (Not part of the boilerplate)
+# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
+set(EXTRA_COMPONENT_DIRS ../../../../common_components/protocol_examples_common)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(asio_sock4)

components/asio/examples/socks4/README.md

@@ -0,0 +1,73 @@
+| Supported Targets | ESP32 | ESP32-S2 |
+| ----------------- | ----- | -----   |
+
+# Async request using ASIO
+
+(See the README.md file in the upper level 'examples' directory for more information about examples.)
+
+The application aims to show how to connect to a Socks4 proxy using async operations with ASIO. The SOCKS protocol is 
+briefly described by the diagram below. 
+
+                   ┌──────┐                   ┌─────┐            ┌──────┐                                        
+                   │Client│                   │Proxy│            │Target│                                        
+                   └──┬───┘                   └──┬──┘            └──┬───┘                                        
+                      │                          │                  │                                            
+                      │                        ╔═╧══════════════╗   │                                            
+══════════════════════╪════════════════════════╣ Initialization ╠═══╪════════════════════════════════════════════
+                      │                        ╚═╤══════════════╝   │                                            
+                      │                          │                  │                                            
+  ╔══════════════════╗│                          │                  │                                            
+  ║We establish a   ░║│     Socket Connection    │                  │                                            
+  ║TCP connection    ║│ <─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ >                  │                                            
+  ║and get a socket  ║│                          │                  │                                            
+  ╚══════════════════╝│                          │                  │                                            
+                      │                          │                  │                                            
+                      │                        ╔═╧══════════════╗   │                                            
+══════════════════════╪════════════════════════╣ Socks Protocol ╠═══╪════════════════════════════════════════════
+                      │                        ╚═╤══════════════╝   │                                            
+                      │                          │                  │                                            
+                      │ Client Connection Request│                  │                                            
+                      │ ─────────────────────────>                  │                                            
+                      │                          │                  │                                            
+                      │                          │                  │                                            
+                      │             ╔════════════╪═══════╤══════════╪════════════════════════════════╗           
+                      │             ║ TARGET CONNECTION  │          │                                ║           
+                      │             ╟────────────────────┘          │  ╔═══════════════════╗         ║           
+                      │             ║            │ Socket Connection│  ║Proxy establishes ░║         ║           
+                      │             ║            │ <─ ─ ─ ─ ─ ─ ─ ─ >  ║ TCPconnection     ║         ║           
+                      │             ║            │                  │  ║ with target host  ║         ║           
+                      │             ╚════════════╪══════════════════╪══╚═══════════════════╝═════════╝           
+                      │                          │                  │                                            
+                      │      Response packet     │                  │                                            
+                      │ <─────────────────────────                  │                                            
+                      │                          │                  │                                            
+                      │                          │                  │                                            
+                      │                          │  ╔═══════╗       │                                            
+══════════════════════╪══════════════════════════╪══╣ Usage ╠═══════╪════════════════════════════════════════════
+                      │                          │  ╚═══════╝       │                                            
+                      │                          │                  │                                            
+   ╔═════════════════╗│                          │                  │                                            
+   ║Client uses the ░║│                          │                  │                                            
+   ║ socket opened   ║│                          │                  │                                            
+   ║ with proxy      ║│ <─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─>                                            
+   ║to communicate   ║│                          │                  │                                            
+   ║                 ║│                          │                  │                                            
+   ╚═════════════════╝┴───┐                   ┌──┴──┐            ┌──┴───┐                                        
+                   │Client│                   │Proxy│            │Target│                                        
+                   └──────┘                   └─────┘            └──────┘                                        
+
+
+# Configure and Building example
+
+This example requires the proxy address to be configured. You can do this using the menuconfig option.
+Proxy address and port must be configured in order for this example to work. 
+
+If using Linux ssh can be used as a proxy for testing. 
+
+```
+ssh -N -v -D 0.0.0.0:1080 localhost
+```
+# Async operations composition and automatic lifetime control
+
+For documentation about the structure of this example look into [async\_request README](../async_request/README.md).
+

components/asio/examples/socks4/main/CMakeLists.txt

@@ -0,0 +1,2 @@
+idf_component_register(SRCS "socks4.cpp"
+                    INCLUDE_DIRS ".")

components/asio/examples/socks4/main/Kconfig.projbuild

@@ -0,0 +1,16 @@
+menu "Example Configuration"
+
+    config EXAMPLE_PROXY_ADDRESS
+        string "Proxy address"
+        default "myproxy"
+        help
+            Address of the proxy to be used.
+
+    config EXAMPLE_PROXY_SERVICE
+        string "Proxy Service Type"
+        default "myport"
+        help
+            Service type. Due to a limitation of lwip, must
+            be the port number e.g. "1080".
+
+endmenu

components/asio/examples/socks4/main/socks4.cpp

@@ -0,0 +1,393 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: CC0-1.0
+ *
+ *
+ *  ASIO Socks4 example
+*/
+
+#include <string>
+#include <array>
+#include <asio.hpp>
+#include <memory>
+#include <system_error>
+#include <utility>
+#include "esp_log.h"
+#include "socks4.hpp"
+#include "nvs_flash.h"
+#include "esp_event.h"
+#include "protocol_examples_common.h"
+
+constexpr auto TAG = "asio_socks4";
+using asio::ip::tcp;
+
+namespace {
+
+void esp_init()
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+    esp_log_level_set("async_request", ESP_LOG_DEBUG);
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+}
+
+/**
+ * @brief Simple class to add the resolver to a chain of actions
+ *
+ */
+class AddressResolution : public std::enable_shared_from_this<AddressResolution> {
+public:
+    explicit AddressResolution(asio::io_context &context) : ctx(context), resolver(ctx) {}
+
+    /**
+     * @brief Initiator function for the address resolution
+     *
+     * @tparam CompletionToken callable responsible to use the results.
+     *
+     * @param host Host address
+     * @param port Port for the target, must be number due to a limitation on lwip.
+     */
+    template<class CompletionToken>
+    void resolve(const std::string &host, const std::string &port, CompletionToken &&completion_handler)
+    {
+        auto self(shared_from_this());
+        resolver.async_resolve(host, port, [self, completion_handler](const asio::error_code & error, tcp::resolver::results_type results) {
+            if (error) {
+                ESP_LOGE(TAG, "Failed to resolve: %s", error.message().c_str());
+                return;
+            }
+            completion_handler(self, results);
+        });
+    }
+
+private:
+    asio::io_context &ctx;
+    tcp::resolver resolver;
+
+};
+
+/**
+ * @brief Connection class
+ *
+ * The lowest level dependency on our asynchronous task, Connection provide an interface to TCP sockets.
+ * A similar class could be provided for a TLS connection.
+ *
+ * @note: All read and write operations are written on an explicit strand, even though an implicit strand
+ * occurs in this example since we run the io context in a single task.
+ *
+ */
+class Connection : public std::enable_shared_from_this<Connection> {
+public:
+    explicit Connection(asio::io_context &context) : ctx(context), strand(context), socket(ctx) {}
+
+    /**
+     * @brief Start the connection
+     *
+     * Async operation to start a connection. As the final act of the process the Connection class pass a
+     * std::shared_ptr of itself to the completion_handler.
+     * Since it uses std::shared_ptr as an automatic control of its lifetime this class must be created
+     * through a std::make_shared call.
+     *
+     * @tparam completion_handler A callable to act as the final handler for the process.
+     * @param host host address
+     * @param port port number - due to a limitation on lwip implementation this should be the number not the
+     *                           service name typically seen in ASIO examples.
+     *
+     * @note The class could be modified to store the completion handler, as a member variable, instead of
+     * pass it along asynchronous calls to allow the process to run again completely.
+     *
+     */
+    template<class CompletionToken>
+    void start(tcp::resolver::results_type results, CompletionToken &&completion_handler)
+    {
+        connect(results, completion_handler);
+    }
+
+    /**
+     * @brief Start an async write on the socket
+     *
+     * @tparam data
+     * @tparam completion_handler A callable to act as the final handler for the process.
+     *
+     */
+    template<class DataType, class CompletionToken>
+    void write_async(const DataType &data, CompletionToken &&completion_handler)
+    {
+        asio::async_write(socket, data, asio::bind_executor(strand, completion_handler));
+    }
+
+    /**
+     * @brief Start an async read on the socket
+     *
+     * @tparam data
+     * @tparam completion_handler A callable to act as the final handler for the process.
+     *
+     */
+    template<class DataBuffer, class CompletionToken>
+    void read_async(DataBuffer &&in_data, CompletionToken &&completion_handler)
+    {
+        asio::async_read(socket, in_data, asio::bind_executor(strand, completion_handler));
+    }
+
+private:
+
+    template<class CompletionToken>
+    void connect(tcp::resolver::results_type results, CompletionToken &&completion_handler)
+    {
+        auto self(shared_from_this());
+        asio::async_connect(socket, results, [self, completion_handler](const asio::error_code & error, [[maybe_unused]] const tcp::endpoint & endpoint) {
+            if (error) {
+                ESP_LOGE(TAG, "Failed to connect: %s", error.message().c_str());
+                return;
+            }
+            completion_handler(self);
+        });
+    }
+    asio::io_context &ctx;
+    asio::io_context::strand strand;
+    tcp::socket socket;
+};
+
+}
+
+namespace Socks {
+
+struct ConnectionData {
+    ConnectionData(socks4::request::command_type cmd, const asio::ip::tcp::endpoint &endpoint,
+                   const std::string &user_id) : request(cmd, endpoint, user_id) {};
+    socks4::request request;
+    socks4::reply reply;
+};
+
+template<class CompletionToken>
+void async_connect(asio::io_context &context, std::string proxy, std::string proxy_port, std::string host, std::string port, CompletionToken &&completion_handler)
+{
+    /*
+     * The first step is to resolve the address of the proxy we want to connect to.
+     * The AddressResolution itself is injected to the completion handler.
+     */
+    // Resolve proxy
+    std::make_shared<AddressResolution>(context)->resolve(proxy, proxy_port,
+    [&context, host, port, completion_handler](std::shared_ptr<AddressResolution> resolver, tcp::resolver::results_type proxy_resolution) {
+        // We also need to resolve the target host address
+        resolver->resolve(host, port, [&context, proxy_resolution, completion_handler](std::shared_ptr<AddressResolution> resolver, tcp::resolver::results_type host_resolution) {
+            // Make connection with the proxy
+            ESP_LOGI(TAG, "Startig Proxy Connection");
+            std::make_shared<Connection>(context)->start(proxy_resolution,
+            [resolver, host_resolution, completion_handler](std::shared_ptr<Connection> connection) {
+                auto connect_data = std::make_shared<ConnectionData>(socks4::request::connect, *host_resolution, "");
+            ESP_LOGI(TAG, "Sending Request to proxy for host connection.");
+                connection->write_async(connect_data->request.buffers(), [connection, connect_data, completion_handler](std::error_code error, std::size_t bytes_received) {
+                    if (error) {
+                        ESP_LOGE(TAG, "Proxy request write error: %s", error.message().c_str());
+                        return;
+                    }
+                    connection->read_async(connect_data->reply.buffers(), [connection, connect_data, completion_handler](std::error_code error, std::size_t bytes_received) {
+                        if (error) {
+
+                            ESP_LOGE(TAG, "Proxy response read error: %s", error.message().c_str());
+                            return;
+                        }
+                        if (!connect_data->reply.success()) {
+                            ESP_LOGE(TAG, "Proxy error: %#x", connect_data->reply.status());
+                        }
+                        completion_handler(connection);
+
+                    });
+
+                });
+
+            });
+
+        });
+    });
+
+}
+} // namespace Socks
+
+namespace Http {
+enum class Method { GET };
+
+/**
+ * @brief Simple HTTP request class
+ *
+ * The user needs to write the request information direct to header and body fields.
+ *
+ * Only GET verb is provided.
+ *
+ */
+class Request {
+public:
+    Request(Method method, std::string host, std::string port, const std::string &target) : host_data(std::move(host)), port_data(std::move(port))
+    {
+        header_data.append("GET ");
+        header_data.append(target);
+        header_data.append(" HTTP/1.1");
+        header_data.append("\r\n");
+        header_data.append("Host: ");
+        header_data.append(host_data);
+        header_data.append("\r\n");
+        header_data.append("\r\n");
+    };
+
+    void set_header_field(std::string const &field)
+    {
+        header_data.append(field);
+    }
+
+    void append_to_body(std::string const &data)
+    {
+        body_data.append(data);
+    };
+
+    const std::string &host() const
+    {
+        return host_data;
+    }
+
+    const std::string &service_port() const
+    {
+        return port_data;
+    }
+
+    const std::string &header() const
+    {
+        return header_data;
+    }
+
+    const std::string &body() const
+    {
+        return body_data;
+    }
+
+private:
+    std::string host_data;
+    std::string port_data;
+    std::string header_data;
+    std::string body_data;
+};
+
+/**
+ * @brief Simple HTTP response class
+ *
+ * The response is built from received data and only parsed to split header and body.
+ *
+ * A copy of the received data is kept.
+ *
+ */
+struct Response {
+    /**
+     * @brief Construct a response from a contiguous buffer.
+     *
+     * Simple http parsing.
+     *
+     */
+    template<class DataIt>
+    explicit Response(DataIt data, size_t size)
+    {
+        raw_response = std::string(data, size);
+
+        auto header_last = raw_response.find("\r\n\r\n");
+        if (header_last != std::string::npos) {
+            header = raw_response.substr(0, header_last);
+        }
+        body = raw_response.substr(header_last + 3);
+    }
+    /**
+     * @brief Print response content.
+     */
+    void print()
+    {
+        ESP_LOGI(TAG, "Header :\n %s", header.c_str());
+        ESP_LOGI(TAG, "Body : \n %s", body.c_str());
+    }
+
+    std::string raw_response;
+    std::string header;
+    std::string body;
+};
+
+/** @brief HTTP Session
+ *
+ * Session class to handle HTTP protocol implementation.
+ *
+ */
+class Session : public std::enable_shared_from_this<Session> {
+public:
+    explicit Session(std::shared_ptr<Connection> connection_in) : connection(std::move(connection_in))
+    {
+    }
+
+    template<class CompletionToken>
+    void send_request(const Request &request, CompletionToken &&completion_handler)
+    {
+        auto self = shared_from_this();
+        send_data = { asio::buffer(request.header()), asio::buffer(request.body()) };
+        connection->write_async(send_data, [self, &completion_handler](std::error_code error, std::size_t bytes_transfered) {
+            if (error) {
+                ESP_LOGE(TAG, "Request write error: %s", error.message().c_str());
+                return;
+            }
+            ESP_LOGD(TAG, "Bytes Transfered: %d", bytes_transfered);
+            self->get_response(completion_handler);
+        });
+    }
+
+private:
+    template<class CompletionToken>
+    void get_response(CompletionToken &&completion_handler)
+    {
+        auto self = shared_from_this();
+        connection->read_async(asio::buffer(receive_buffer), [self, &completion_handler](std::error_code error, std::size_t bytes_received) {
+            if (error and error.value() != asio::error::eof) {
+                return;
+            }
+            ESP_LOGD(TAG, "Bytes Received: %d", bytes_received);
+            if (bytes_received == 0) {
+                return;
+            }
+            Response response(std::begin(self->receive_buffer), bytes_received);
+
+            completion_handler(self, response);
+        });
+    }
+    /*
+     * For this example we assumed 2048 to be enough for the receive_buffer
+     */
+    std::array<char, 2048> receive_buffer;
+    /*
+     * The hardcoded 2 below is related to the type we receive the data to send. We gather the parts from Request, header
+     * and body, to send avoiding the copy.
+     */
+    std::array<asio::const_buffer, 2> send_data;
+    std::shared_ptr<Connection> connection;
+};
+}// namespace Http
+
+extern "C" void app_main(void)
+{
+    // Basic initialization of ESP system
+    esp_init();
+
+    asio::io_context io_context;
+    Http::Request request(Http::Method::GET, "www.httpbin.org", "80", "/get");
+    Socks::async_connect(io_context, CONFIG_EXAMPLE_PROXY_ADDRESS, CONFIG_EXAMPLE_PROXY_SERVICE, request.host(), request.service_port(),
+    [&request](std::shared_ptr<Connection> connection) {
+        // Now we create a HTTP::Session and inject the necessary connection.
+        std::make_shared<Http::Session>(connection)->send_request(request, [](std::shared_ptr<Http::Session> session, Http::Response response) {
+            response.print();
+        });
+    });
+    // io_context.run will block until all the tasks on the context are done.
+    io_context.run();
+    ESP_LOGI(TAG, "Context run done");
+
+    ESP_ERROR_CHECK(example_disconnect());
+}

components/asio/examples/socks4/main/socks4.hpp

@@ -0,0 +1,143 @@
+//
+// socks4.hpp
+// ~~~~~~~~~~
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef SOCKS4_HPP
+#define SOCKS4_HPP
+
+#include <array>
+#include <string>
+#include <asio/buffer.hpp>
+#include <asio/ip/tcp.hpp>
+
+namespace socks4 {
+
+const unsigned char version = 0x04;
+
+class request
+{
+public:
+  enum command_type
+  {
+    connect = 0x01,
+    bind = 0x02
+  };
+
+  request(command_type cmd, const asio::ip::tcp::endpoint& endpoint,
+      const std::string& user_id)
+    : version_(version),
+      command_(cmd),
+      user_id_(user_id),
+      null_byte_(0)
+  {
+    // Only IPv4 is supported by the SOCKS 4 protocol.
+    if (endpoint.protocol() != asio::ip::tcp::v4())
+    {
+      throw asio::system_error(
+          asio::error::address_family_not_supported);
+    }
+
+    // Convert port number to network byte order.
+    unsigned short port = endpoint.port();
+    port_high_byte_ = (port >> 8) & 0xff;
+    port_low_byte_ = port & 0xff;
+
+    // Save IP address in network byte order.
+    address_ = endpoint.address().to_v4().to_bytes();
+  }
+
+  std::array<asio::const_buffer, 7> buffers() const
+  {
+    return
+    {
+      {
+        asio::buffer(&version_, 1),
+        asio::buffer(&command_, 1),
+        asio::buffer(&port_high_byte_, 1),
+        asio::buffer(&port_low_byte_, 1),
+        asio::buffer(address_),
+        asio::buffer(user_id_),
+        asio::buffer(&null_byte_, 1)
+      }
+    };
+  }
+
+private:
+  unsigned char version_;
+  unsigned char command_;
+  unsigned char port_high_byte_;
+  unsigned char port_low_byte_;
+  asio::ip::address_v4::bytes_type address_;
+  std::string user_id_;
+  unsigned char null_byte_;
+};
+
+class reply
+{
+public:
+  enum status_type
+  {
+    request_granted = 0x5a,
+    request_failed = 0x5b,
+    request_failed_no_identd = 0x5c,
+    request_failed_bad_user_id = 0x5d
+  };
+
+  reply()
+    : null_byte_(0),
+      status_()
+  {
+  }
+
+  std::array<asio::mutable_buffer, 5> buffers()
+  {
+    return
+    {
+      {
+        asio::buffer(&null_byte_, 1),
+        asio::buffer(&status_, 1),
+        asio::buffer(&port_high_byte_, 1),
+        asio::buffer(&port_low_byte_, 1),
+        asio::buffer(address_)
+      }
+    };
+  }
+
+  bool success() const
+  {
+    return null_byte_ == 0 && status_ == request_granted;
+  }
+
+  unsigned char status() const
+  {
+    return status_;
+  }
+
+  asio::ip::tcp::endpoint endpoint() const
+  {
+    unsigned short port = port_high_byte_;
+    port = (port << 8) & 0xff00;
+    port = port | port_low_byte_;
+
+    asio::ip::address_v4 address(address_);
+
+    return asio::ip::tcp::endpoint(address, port);
+  }
+
+private:
+  unsigned char null_byte_;
+  unsigned char status_;
+  unsigned char port_high_byte_;
+  unsigned char port_low_byte_;
+  asio::ip::address_v4::bytes_type address_;
+};
+
+} // namespace socks4
+
+#endif // SOCKS4_HPP

components/asio/examples/socks4/sdkconfig.defaults

@@ -0,0 +1,3 @@
+CONFIG_COMPILER_CXX_EXCEPTIONS=y
+CONFIG_COMPILER_CXX_RTTI=y
+CONFIG_COMPILER_CXX_EXCEPTIONS_EMG_POOL_SIZE=0

components/asio/examples/ssl_client_server/CMakeLists.txt

@@ -0,0 +1,11 @@
+# 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 3.16)
+
+# (Not part of the boilerplate)
+# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
+set(EXTRA_COMPONENT_DIRS ../../../../common_components/protocol_examples_common)
+set(EXCLUDE_COMPONENTS openssl)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(asio_ssl_client_server)

components/asio/examples/ssl_client_server/README.md

@@ -0,0 +1,88 @@
+| Supported Targets | ESP32 | ESP32-S2 | ESP32-S3 | ESP32-C3 |
+| ----------------- | ----- | -------- | -------- | -------- |
+
+# Asio SSL client/server example
+
+Simple Asio client and server with SSL/TLS transport
+
+## How to Use Example
+
+### Hardware Required
+
+This example can be executed on any ESP platform board. No external connection is required, it is recommended though
+to connect to internet or a local network via WiFi or Ethernet to easily exercise features of this example.
+
+### Configure the project
+
+* Open the project configuration menu (`idf.py menuconfig`)
+* Configure Wi-Fi or Ethernet under "Example Connection Configuration" menu. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../../README.md) for more details.
+* Enable the ASIO client and set server's host name to examine client's functionality.
+The ASIO client connects to the configured server and sends default payload string "GET / HTTP/1.1"
+* Enable the ASIO server to examine server's functionality. The ASIO server listens to connection and echos back what was received.
+
+### Build and Flash
+
+Build the project and flash it to the board, then run monitor tool to view serial output:
+
+```
+idf.py -p PORT flash monitor
+```
+
+(To exit the serial monitor, type ``Ctrl-]``.)
+
+See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
+
+## Example Output
+
+### Client connecting to public server
+
+The below output illustrates the client connecting to a public https server.
+
+```
+I (1267) example_connect: Waiting for IP(s)
+I (2587) wifi:new:<11,0>, old:<1,0>, ap:<255,255>, sta:<11,0>, prof:1
+I (3367) wifi:state: init -> auth (b0)
+I (3377) wifi:state: auth -> assoc (0)
+I (3387) wifi:state: assoc -> run (10)
+I (3397) wifi:security type: 3, phy: bgn, rssi: -49
+I (3397) wifi:pm start, type: 1
+I (3457) wifi:AP's beacon interval = 102400 us, DTIM period = 1
+I (4747) example_connect: Got IPv6 event: Interface "example_connect: sta" address: fe80:0000:0000:0000:260a:xxxx:xxxx:xxxx, type: ESP_IP6_ADDR_IS_LINK_LOCAL
+I (5247) esp_netif_handlers: example_connect: sta ip: 192.168.32.69, mask: 255.255.252.0, gw: 192.168.32.3
+I (5247) example_connect: Got IPv4 event: Interface "example_connect: sta" address: 192.168.32.69
+I (5257) example_connect: Connected to example_connect: sta
+I (5257) example_connect: - IPv4 address: 192.168.32.69
+I (5267) example_connect: - IPv6 address: fe80:0000:0000:0000:260a:xxxx:xxxx:xxxx, type: ESP_IP6_ADDR_IS_LINK_LOCAL
+W (5277) esp32_asio_pthread: pthread_condattr_setclock: not yet supported!
+W (5297) esp32_asio_pthread: pthread_condattr_setclock: not yet supported!
+Reply: HTTP/1.1 200 OK
+D
+```
+### Both server and client enabled
+
+The below output demonstrates the client connecting to the ASIO server via loopback interface, so no WiFi, nor Ethernet connection
+was established.
+```
+I (0) cpu_start: App cpu up.
+I (495) heap_init: Initializing. RAM available for dynamic allocation:
+I (502) heap_init: At 3FFAE6E0 len 00001920 (6 KiB): DRAM
+I (508) heap_init: At 3FFB5400 len 0002AC00 (171 KiB): DRAM
+I (515) heap_init: At 3FFE0440 len 00003AE0 (14 KiB): D/IRAM
+I (521) heap_init: At 3FFE4350 len 0001BCB0 (111 KiB): D/IRAM
+I (527) heap_init: At 4008BB80 len 00014480 (81 KiB): IRAM
+I (534) cpu_start: Pro cpu start user code
+I (556) spi_flash: detected chip: gd
+I (556) spi_flash: flash io: dio
+W (556) spi_flash: Detected size(4096k) larger than the size in the binary image header(2048k). Using the size in the binary image header.
+I (566) cpu_start: Starting scheduler on PRO CPU.
+I (0) cpu_start: Starting scheduler on APP CPU.
+I (600) example_connect: Waiting for IP(s)
+W (600) esp32_asio_pthread: pthread_condattr_setclock: not yet supported!
+W (1610) esp32_asio_pthread: pthread_condattr_setclock: not yet supported!
+W (1610) esp32_asio_pthread: pthread_condattr_setclock: not yet supported!
+Server received: GET / HTTP/1.1
+
+
+Reply: GET / HTTP/1.1
+```
+See the README.md file in the upper level 'examples' directory for more information about examples.

components/asio/examples/ssl_client_server/example_test.py

@@ -0,0 +1,16 @@
+from __future__ import unicode_literals
+
+import ttfw_idf
+
+
+@ttfw_idf.idf_example_test(env_tag='Example_GENERIC', target=['esp32', 'esp32c3'])
+def test_examples_asio_ssl(env, extra_data):
+
+    dut = env.get_dut('asio_ssl_client_server', 'examples/protocols/asio/ssl_client_server')
+    dut.start_app()
+
+    dut.expect('Reply: GET / HTTP/1.1')
+
+
+if __name__ == '__main__':
+    test_examples_asio_ssl()

components/asio/examples/ssl_client_server/main/CMakeLists.txt

@@ -0,0 +1,3 @@
+idf_component_register(SRCS "asio_ssl_main.cpp"
+                    INCLUDE_DIRS "."
+        EMBED_TXTFILES ca.crt server.key srv.crt)

components/asio/examples/ssl_client_server/main/Kconfig.projbuild

@@ -0,0 +1,36 @@
+menu "Example Configuration"
+
+    config EXAMPLE_CLIENT
+        bool "Enable TLS client"
+        default y
+        help
+            Choose this option to use ASIO TLS/SSL client functionality
+
+    config EXAMPLE_PORT
+        string "ASIO port number"
+        default "443"
+        help
+            Port number used by ASIO example.
+
+    config EXAMPLE_SERVER
+        bool "Enable TLS server"
+        default n
+        help
+            Choose this option to use ASIO TLS/SSL server functionality
+
+    config EXAMPLE_SERVER_NAME
+        string "ASIO server name or IP"
+        default "www.google.com"
+        depends on EXAMPLE_CLIENT
+        help
+            Asio example server ip for the ASIO client to connect to.
+
+    config EXAMPLE_CLIENT_VERIFY_PEER
+        bool "Client to verify peer"
+        default n
+        depends on EXAMPLE_CLIENT
+        help
+            This option sets client's mode to verify peer, default is
+            verify-none
+
+endmenu

components/asio/examples/ssl_client_server/main/asio_ssl_main.cpp

@@ -0,0 +1,272 @@
+//
+// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <string>
+#include "protocol_examples_common.h"
+#include "esp_event.h"
+#include "nvs_flash.h"
+#include <cstdlib>
+#include <iostream>
+#include <chrono>
+#include <thread>
+#include "asio.hpp"
+#include "asio/ssl.hpp"
+#include "asio/buffer.hpp"
+#include "esp_pthread.h"
+
+extern const unsigned char server_pem_start[] asm("_binary_srv_crt_start");
+extern const unsigned char server_pem_end[]   asm("_binary_srv_crt_end");
+
+extern const unsigned char cacert_pem_start[] asm("_binary_ca_crt_start");
+extern const unsigned char cacert_pem_end[]   asm("_binary_ca_crt_end");
+
+extern const unsigned char prvtkey_pem_start[] asm("_binary_server_key_start");
+extern const unsigned char prvtkey_pem_end[]   asm("_binary_server_key_end");
+
+static const asio::const_buffer cert_chain(cacert_pem_start, cacert_pem_end - cacert_pem_start);
+static const asio::const_buffer privkey(prvtkey_pem_start, prvtkey_pem_end - prvtkey_pem_start);
+static const asio::const_buffer server_cert(server_pem_start, server_pem_end - server_pem_start);
+
+using asio::ip::tcp;
+
+static const std::size_t max_length = 1024;
+
+class Client {
+public:
+    Client(asio::io_context &io_context,
+           asio::ssl::context &context,
+           const tcp::resolver::results_type &endpoints)
+        : socket_(io_context, context)
+    {
+
+#if CONFIG_EXAMPLE_CLIENT_VERIFY_PEER
+        socket_.set_verify_mode(asio::ssl::verify_peer);
+#else
+        socket_.set_verify_mode(asio::ssl::verify_none);
+#endif // CONFIG_EXAMPLE_CLIENT_VERIFY_PEER
+
+        connect(endpoints);
+    }
+
+private:
+    void connect(const tcp::resolver::results_type &endpoints)
+    {
+        asio::async_connect(socket_.lowest_layer(), endpoints,
+                            [this](const std::error_code & error,
+        const tcp::endpoint & /*endpoint*/) {
+            if (!error) {
+                handshake();
+            } else {
+                std::cout << "Connect failed: " << error.message() << "\n";
+            }
+        });
+    }
+
+    void handshake()
+    {
+        socket_.async_handshake(asio::ssl::stream_base::client,
+        [this](const std::error_code & error) {
+            if (!error) {
+                send_request();
+            } else {
+                std::cout << "Handshake failed: " << error.message() << "\n";
+            }
+        });
+    }
+
+    void send_request()
+    {
+        size_t request_length = std::strlen(request_);
+
+        asio::async_write(socket_,
+                          asio::buffer(request_, request_length),
+        [this](const std::error_code & error, std::size_t length) {
+            if (!error) {
+                receive_response(length);
+            } else {
+                std::cout << "Write failed: " << error.message() << "\n";
+            }
+        });
+    }
+
+    void receive_response(std::size_t length)
+    {
+        asio::async_read(socket_,
+                         asio::buffer(reply_, length),
+        [this](const std::error_code & error, std::size_t length) {
+            if (!error) {
+                std::cout << "Reply: ";
+                std::cout.write(reply_, length);
+                std::cout << "\n";
+            } else {
+                std::cout << "Read failed: " << error.message() << "\n";
+            }
+        });
+    }
+
+    asio::ssl::stream<tcp::socket> socket_;
+    char request_[max_length] = "GET / HTTP/1.1\r\n\r\n";
+    char reply_[max_length];
+};
+
+class Session : public std::enable_shared_from_this<Session> {
+public:
+    Session(tcp::socket socket, asio::ssl::context &context)
+        : socket_(std::move(socket), context)
+    {
+    }
+
+    void start()
+    {
+        do_handshake();
+    }
+
+private:
+    void do_handshake()
+    {
+        auto self(shared_from_this());
+        socket_.async_handshake(asio::ssl::stream_base::server,
+        [this, self](const std::error_code & error) {
+            if (!error) {
+                do_read();
+            }
+        });
+    }
+
+    void do_read()
+    {
+        auto self(shared_from_this());
+        socket_.async_read_some(asio::buffer(data_),
+        [this, self](const std::error_code & ec, std::size_t length) {
+            if (!ec) {
+                std::cout << "Server received: ";
+                std::cout.write(data_, length);
+                std::cout << std::endl;
+                do_write(length);
+            }
+        });
+    }
+
+    void do_write(std::size_t length)
+    {
+        auto self(shared_from_this());
+        asio::async_write(socket_, asio::buffer(data_, length),
+                          [this, self](const std::error_code & ec,
+        std::size_t /*length*/) {
+            if (!ec) {
+                do_read();
+            }
+        });
+    }
+
+    asio::ssl::stream<tcp::socket> socket_;
+    char data_[max_length];
+};
+
+class Server {
+public:
+    Server(asio::io_context &io_context, unsigned short port)
+        : acceptor_(io_context, tcp::endpoint(tcp::v4(), port)),
+          context_(asio::ssl::context::tls_server)
+    {
+        context_.set_options(
+            asio::ssl::context::default_workarounds
+            | asio::ssl::context::no_sslv2);
+        context_.use_certificate_chain(server_cert);
+        context_.use_private_key(privkey, asio::ssl::context::pem);
+
+        do_accept();
+    }
+
+private:
+    void do_accept()
+    {
+        acceptor_.async_accept(
+        [this](const std::error_code & error, tcp::socket socket) {
+            if (!error) {
+                std::make_shared<Session>(std::move(socket), context_)->start();
+            }
+
+            do_accept();
+        });
+    }
+
+    tcp::acceptor acceptor_;
+    asio::ssl::context context_;
+};
+
+void set_thread_config(const char *name, int stack, int prio)
+{
+    auto cfg = esp_pthread_get_default_config();
+    cfg.thread_name = name;
+    cfg.stack_size = stack;
+    cfg.prio = prio;
+    esp_pthread_set_cfg(&cfg);
+}
+
+void ssl_server_thread()
+{
+    asio::io_context io_context;
+
+    Server s(io_context, 443);
+
+    io_context.run();
+}
+
+void ssl_client_thread()
+{
+    asio::io_context io_context;
+
+    tcp::resolver resolver(io_context);
+    std::string server_ip = CONFIG_EXAMPLE_SERVER_NAME;
+    std::string server_port = CONFIG_EXAMPLE_PORT;
+    auto endpoints = resolver.resolve(server_ip, server_port);
+
+    asio::ssl::context ctx(asio::ssl::context::tls_client);
+#if CONFIG_EXAMPLE_CLIENT_VERIFY_PEER
+    ctx.add_certificate_authority(cert_chain);
+#endif // CONFIG_EXAMPLE_CLIENT_VERIFY_PEER
+
+    Client c(io_context, ctx, endpoints);
+
+    io_context.run();
+
+}
+
+
+extern "C" void app_main(void)
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+    esp_netif_init();
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+
+    /* This helper function configures blocking UART I/O */
+    ESP_ERROR_CHECK(example_configure_stdin_stdout());
+    std::vector<std::thread> work_threads;
+
+#if CONFIG_EXAMPLE_SERVER
+    set_thread_config("Server", 16 * 1024, 5);
+    work_threads.emplace_back(std::thread(ssl_server_thread));
+    std::this_thread::sleep_for(std::chrono::seconds(1));
+#endif // CONFIG_EXAMPLE_SERVER
+
+#if CONFIG_EXAMPLE_CLIENT
+    set_thread_config("Client", 16 * 1024, 5);
+    work_threads.emplace_back(ssl_client_thread);
+#endif // CONFIG_EXAMPLE_CLIENT
+
+    for (auto &t : work_threads) {
+        t.join();
+    }
+
+}

components/asio/examples/ssl_client_server/main/ca.crt

@@ -0,0 +1,22 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

components/asio/examples/ssl_client_server/main/server.key

@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----

components/asio/examples/ssl_client_server/main/srv.crt

@@ -0,0 +1,18 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

components/asio/examples/ssl_client_server/partitions.csv

@@ -0,0 +1,5 @@
+# Name,   Type, SubType, Offset,  Size, Flags
+# Note: if you have increased the bootloader size, make sure to update the offsets to avoid overlap
+nvs,      data, nvs,     0x9000,  0x6000,
+phy_init, data, phy,     0xf000,  0x1000,
+factory,  app,  factory, 0x10000, 1400000,

components/asio/examples/ssl_client_server/sdkconfig.ci

@@ -0,0 +1,6 @@
+CONFIG_EXAMPLE_CLIENT=y
+CONFIG_EXAMPLE_SERVER=y
+CONFIG_EXAMPLE_SERVER_NAME="localhost"
+CONFIG_EXAMPLE_CONNECT_WIFI=n
+CONFIG_EXAMPLE_CONNECT_ETHERNET=n
+CONFIG_EXAMPLE_CLIENT_VERIFY_PEER=y

components/asio/examples/ssl_client_server/sdkconfig.defaults

@@ -0,0 +1,10 @@
+CONFIG_ASIO_SSL_SUPPORT=y
+CONFIG_PARTITION_TABLE_CUSTOM=y
+CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="partitions.csv"
+CONFIG_PARTITION_TABLE_FILENAME="partitions.csv"
+
+#
+# Partition Table
+#
+# Leave some room for larger apps without needing to reduce other features
+CONFIG_PARTITION_TABLE_SINGLE_APP_LARGE=y

components/asio/examples/tcp_echo_server/CMakeLists.txt

@@ -0,0 +1,10 @@
+# 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 3.16)
+
+# (Not part of the boilerplate)
+# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
+set(EXTRA_COMPONENT_DIRS ../../../../common_components/protocol_examples_common)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(asio_tcp_echo_server)

components/asio/examples/tcp_echo_server/README.md

@@ -0,0 +1,22 @@
+| Supported Targets | ESP32 | ESP32-S2 | ESP32-S3 | ESP32-C3 |
+| ----------------- | ----- | -------- | -------- | -------- |
+
+# Asio TCP echo server example
+
+Simple Asio TCP echo server using WiFi STA or Ethernet.
+
+## Example workflow
+
+- Wi-Fi or Ethernet connection is established, and IP address is obtained.
+- Asio TCP server is started on port number defined through the project configuration.
+- Server receives and echoes back messages transmitted from client.
+
+## Running the example
+
+- Open the project configuration menu (`idf.py menuconfig`) to configure Wi-Fi or Ethernet. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../../README.md) for more details.
+- Set server port number in menuconfig, "Example configuration".
+- Run `idf.py -p PORT flash monitor` to build and upload the example to your board and connect to it's serial terminal.
+- Wait for the board to connect to WiFi or Ethernet (note the IP address).
+- You can now send a TCP message and check it is repeated, for example using netcat `nc IP PORT`.
+
+See the README.md file in the upper level 'examples' directory for more information about examples.

components/asio/examples/tcp_echo_server/asio_tcp_server_test.py

@@ -0,0 +1,47 @@
+import os
+import re
+import socket
+
+import ttfw_idf
+
+
+@ttfw_idf.idf_example_test(env_tag='Example_WIFI_Protocols')
+def test_examples_protocol_asio_tcp_server(env, extra_data):
+    """
+    steps: |
+      1. join AP
+      2. Start server
+      3. Test connects to server and sends a test message
+      4. Test evaluates received test message from server
+      5. Test evaluates received test message on server stdout
+    """
+    test_msg = b'echo message from client to server'
+    dut1 = env.get_dut('tcp_echo_server', 'examples/protocols/asio/tcp_echo_server', dut_class=ttfw_idf.ESP32DUT)
+    # check and log bin size
+    binary_file = os.path.join(dut1.app.binary_path, 'asio_tcp_echo_server.bin')
+    bin_size = os.path.getsize(binary_file)
+    ttfw_idf.log_performance('asio_tcp_echo_server_bin_size', '{}KB'.format(bin_size // 1024))
+    # 1. start test
+    dut1.start_app()
+    # 2. get the server IP address
+    data = dut1.expect(re.compile(r' IPv4 address: ([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)'), timeout=30)
+    # 3. create tcp client and connect to server
+    dut1.expect('ASIO engine is up and running', timeout=1)
+    cli = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    cli.settimeout(30)
+    cli.connect((data[0], 2222))
+    cli.send(test_msg)
+    data = cli.recv(1024)
+    # 4. check the message received back from the server
+    if (data == test_msg):
+        print('PASS: Received correct message')
+        pass
+    else:
+        print('Failure!')
+        raise ValueError('Wrong data received from asi tcp server: {} (expected:{})'.format(data, test_msg))
+    # 5. check the client message appears also on server terminal
+    dut1.expect(test_msg.decode())
+
+
+if __name__ == '__main__':
+    test_examples_protocol_asio_tcp_server()

components/asio/examples/tcp_echo_server/main/CMakeLists.txt

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

components/asio/examples/tcp_echo_server/main/Kconfig.projbuild

@@ -0,0 +1,9 @@
+menu "Example Configuration"
+
+    config EXAMPLE_PORT
+        string "Asio example port number"
+        default "2222"
+        help
+            Port number used by Asio example.
+
+endmenu

components/asio/examples/tcp_echo_server/main/echo_server.cpp

@@ -0,0 +1,108 @@
+#include "asio.hpp"
+#include <string>
+#include <iostream>
+#include "protocol_examples_common.h"
+#include "esp_event.h"
+#include "nvs_flash.h"
+
+using asio::ip::tcp;
+
+class session
+  : public std::enable_shared_from_this<session>
+{
+public:
+  session(tcp::socket socket)
+    : socket_(std::move(socket))
+  {
+  }
+
+  void start()
+  {
+    do_read();
+  }
+
+private:
+  void do_read()
+  {
+    auto self(shared_from_this());
+    socket_.async_read_some(asio::buffer(data_, max_length),
+        [this, self](std::error_code ec, std::size_t length)
+        {
+          if (!ec)
+          {
+            data_[length] = 0;
+            std::cout << data_ << std::endl;
+            do_write(length);
+          }
+        });
+  }
+
+  void do_write(std::size_t length)
+  {
+    auto self(shared_from_this());
+    asio::async_write(socket_, asio::buffer(data_, length),
+        [this, self](std::error_code ec, std::size_t length)
+        {
+          if (!ec)
+          {
+            do_read();
+          }
+        });
+  }
+
+  tcp::socket socket_;
+  enum { max_length = 1024 };
+  char data_[max_length];
+};
+
+class server
+{
+public:
+  server(asio::io_context& io_context, short port)
+    : acceptor_(io_context, tcp::endpoint(tcp::v4(), port))
+  {
+    do_accept();
+  }
+
+private:
+  void do_accept()
+  {
+    acceptor_.async_accept(
+        [this](std::error_code ec, tcp::socket socket)
+        {
+          if (!ec)
+          {
+            std::make_shared<session>(std::move(socket))->start();
+          }
+
+          do_accept();
+        });
+  }
+
+  tcp::acceptor acceptor_;
+};
+
+
+extern "C" void app_main(void)
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+    esp_netif_init();
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+
+    /* This helper function configures blocking UART I/O */
+    ESP_ERROR_CHECK(example_configure_stdin_stdout());
+
+    asio::io_context io_context;
+
+    server s(io_context, std::atoi(CONFIG_EXAMPLE_PORT));
+
+    std::cout << "ASIO engine is up and running" << std::endl;
+
+    io_context.run();
+}

components/asio/examples/tcp_echo_server/sdkconfig.defaults

@@ -0,0 +1,7 @@
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
+
+#
+# Partition Table
+#
+# Leave some room for larger apps without needing to reduce other features
+CONFIG_PARTITION_TABLE_SINGLE_APP_LARGE=y

components/asio/examples/udp_echo_server/CMakeLists.txt

@@ -0,0 +1,10 @@
+# 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 3.16)
+
+# (Not part of the boilerplate)
+# This example uses an extra component for common functions such as Wi-Fi and Ethernet connection.
+set(EXTRA_COMPONENT_DIRS ../../../../common_components/protocol_examples_common)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(asio_udp_echo_server)

components/asio/examples/udp_echo_server/README.md

@@ -0,0 +1,22 @@
+| Supported Targets | ESP32 | ESP32-S2 | ESP32-S3 | ESP32-C3 |
+| ----------------- | ----- | -------- | -------- | -------- |
+
+# Asio UDP echo server example
+
+Simple Asio UDP echo server using WiFi STA or Ethernet.
+
+## Example workflow
+
+- Wi-Fi or Ethernet connection is established, and IP address is obtained.
+- Asio UDP server is started on port number defined through the project configuration
+- Server receives and echoes back messages transmitted from client
+
+## Running the example
+
+- Open the project configuration menu (`idf.py menuconfig`) to configure Wi-Fi or Ethernet. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../../README.md) for more details.
+- Set server port number in menuconfig, "Example configuration".
+- Run `idf.py -p PORT flash monitor` to build and upload the example to your board and connect to it's serial terminal.
+- Wait for the board to connect to WiFi or Ethernet (note the IP address).
+- You can now send a UDP message and check it is repeated, for example using netcat `nc -u IP PORT`.
+
+See the README.md file in the upper level 'examples' directory for more information about examples.

components/asio/examples/udp_echo_server/asio_udp_server_test.py

@@ -0,0 +1,47 @@
+import os
+import re
+import socket
+
+import ttfw_idf
+
+
+@ttfw_idf.idf_example_test(env_tag='Example_WIFI_Protocols')
+def test_examples_protocol_asio_udp_server(env, extra_data):
+    """
+    steps: |
+      1. join AP
+      2. Start server
+      3. Test connects to server and sends a test message
+      4. Test evaluates received test message from server
+      5. Test evaluates received test message on server stdout
+    """
+    test_msg = b'echo message from client to server'
+    dut1 = env.get_dut('udp_echo_server', 'examples/protocols/asio/udp_echo_server', dut_class=ttfw_idf.ESP32DUT)
+    # check and log bin size
+    binary_file = os.path.join(dut1.app.binary_path, 'asio_udp_echo_server.bin')
+    bin_size = os.path.getsize(binary_file)
+    ttfw_idf.log_performance('asio_udp_echo_server_bin_size', '{}KB'.format(bin_size // 1024))
+    # 1. start test
+    dut1.start_app()
+    # 2. get the server IP address
+    data = dut1.expect(re.compile(r' IPv4 address: ([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)'), timeout=30)
+    # 3. create tcp client and connect to server
+    dut1.expect('ASIO engine is up and running', timeout=1)
+    cli = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    cli.settimeout(30)
+    cli.connect((data[0], 2222))
+    cli.send(test_msg)
+    data = cli.recv(1024)
+    # 4. check the message received back from the server
+    if (data == test_msg):
+        print('PASS: Received correct message')
+        pass
+    else:
+        print('Failure!')
+        raise ValueError('Wrong data received from asio udp server: {} (expected:{})'.format(data, test_msg))
+    # 5. check the client message appears also on server terminal
+    dut1.expect(test_msg.decode())
+
+
+if __name__ == '__main__':
+    test_examples_protocol_asio_udp_server()

components/asio/examples/udp_echo_server/main/CMakeLists.txt

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

components/asio/examples/udp_echo_server/main/Kconfig.projbuild

@@ -0,0 +1,9 @@
+menu "Example Configuration"
+
+    config EXAMPLE_PORT
+        string "Asio example port number"
+        default "2222"
+        help
+            Port number used by Asio example.
+
+endmenu

components/asio/examples/udp_echo_server/main/udp_echo_server.cpp

@@ -0,0 +1,90 @@
+//
+// async_udp_echo_server.cpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2018 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <cstdlib>
+#include <iostream>
+
+#include "asio.hpp"
+
+#include "protocol_examples_common.h"
+#include "esp_event.h"
+#include "nvs_flash.h"
+
+
+using asio::ip::udp;
+
+class server
+{
+public:
+  server(asio::io_context& io_context, short port)
+    : socket_(io_context, udp::endpoint(udp::v4(), port))
+  {
+    do_receive();
+  }
+
+  void do_receive()
+  {
+    socket_.async_receive_from(
+        asio::buffer(data_, max_length), sender_endpoint_,
+        [this](std::error_code ec, std::size_t bytes_recvd)
+        {
+          if (!ec && bytes_recvd > 0)
+          {
+            data_[bytes_recvd] = 0;
+            std::cout << data_ << std::endl;
+            do_send(bytes_recvd);
+          }
+          else
+          {
+            do_receive();
+          }
+        });
+  }
+
+  void do_send(std::size_t length)
+  {
+    socket_.async_send_to(
+        asio::buffer(data_, length), sender_endpoint_,
+        [this](std::error_code /*ec*/, std::size_t  bytes /*bytes_sent*/)
+        {
+          do_receive();
+        });
+  }
+
+private:
+  udp::socket socket_;
+  udp::endpoint sender_endpoint_;
+  enum { max_length = 1024 };
+  char data_[max_length];
+};
+
+extern "C" void app_main(void)
+{
+    ESP_ERROR_CHECK(nvs_flash_init());
+    esp_netif_init();
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+
+    /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
+     * Read "Establishing Wi-Fi or Ethernet Connection" section in
+     * examples/protocols/README.md for more information about this function.
+     */
+    ESP_ERROR_CHECK(example_connect());
+
+    /* This helper function configures blocking UART I/O */
+    ESP_ERROR_CHECK(example_configure_stdin_stdout());
+
+    asio::io_context io_context;
+
+    server s(io_context, std::atoi(CONFIG_EXAMPLE_PORT));
+
+    std::cout << "ASIO engine is up and running" << std::endl;
+
+    io_context.run();
+}

components/asio/examples/udp_echo_server/sdkconfig.defaults

@@ -0,0 +1,7 @@
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192
+
+#
+# Partition Table
+#
+# Leave some room for larger apps without needing to reduce other features
+CONFIG_PARTITION_TABLE_SINGLE_APP_LARGE=y

components/asio/idf_component.yml

@@ -0,0 +1,5 @@
+version: "1.0.1"
+description: ASIO
+dependencies:
+  idf:
+    version: ">=5.0"

components/asio/port/include/esp_asio_config.h

@@ -0,0 +1,45 @@
+/*
+ * SPDX-FileCopyrightText: 2018-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#ifndef _ESP_ASIO_CONFIG_H_
+#define _ESP_ASIO_CONFIG_H_
+
+//
+// Enabling exceptions only when they are enabled in menuconfig
+//
+# include <sdkconfig.h>
+# ifndef CONFIG_COMPILER_CXX_EXCEPTIONS
+#  define ASIO_NO_EXCEPTIONS
+# endif   // CONFIG_COMPILER_CXX_EXCEPTIONS
+
+# ifndef CONFIG_COMPILER_RTTI
+#  define ASIO_NO_TYPEID
+# endif   // CONFIG_COMPILER_RTTI
+
+//
+// Use system sockets
+//
+# include "sys/socket.h"
+
+//
+// Specific ASIO feature flags
+//
+# define ASIO_DISABLE_SERIAL_PORT
+# define ASIO_SEPARATE_COMPILATION
+# define ASIO_STANDALONE
+# define ASIO_HAS_PTHREADS
+# define ASIO_DISABLE_CONCEPTS
+
+# ifdef CONFIG_ASIO_USE_ESP_OPENSSL
+#  define ASIO_USE_ESP_OPENSSL
+#  define OPENSSL_NO_ENGINE
+#  define ASIO_SSL_DETAIL_OPENSSL_TYPES_HPP
+#  include "openssl_stub.hpp"
+
+# elif CONFIG_ASIO_USE_ESP_WOLFSSL
+#  define ASIO_USE_WOLFSSL
+# endif   // CONFIG_ASIO_USE_ESP_OPENSSL
+
+#endif // _ESP_ASIO_CONFIG_H_

components/asio/port/include/esp_exception.h

@@ -0,0 +1,30 @@
+/*
+ * SPDX-FileCopyrightText: 2018-2021 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#ifndef _ESP_EXCEPTION_H_
+#define _ESP_EXCEPTION_H_
+
+//
+// This exception stub is enabled only if exceptions are disabled in menuconfig
+//
+#if !defined(CONFIG_COMPILER_CXX_EXCEPTIONS) && defined (ASIO_NO_EXCEPTIONS)
+
+#include "esp_log.h"
+
+//
+// asio exception stub
+//
+namespace asio {
+namespace detail {
+template <typename Exception>
+void throw_exception(const Exception& e)
+{
+  ESP_LOGE("esp32_asio_exception", "Caught exception: %s!", e.what());
+  abort();
+}
+}}
+#endif // CONFIG_COMPILER_CXX_EXCEPTIONS==1 && defined (ASIO_NO_EXCEPTIONS)
+
+#endif // _ESP_EXCEPTION_H_

components/asio/port/include/openssl_stub.hpp

@@ -0,0 +1,46 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+
+#pragma once
+
+//
+// Supply OpenSSL macros and flags for asio-ssl header files
+//
+#define OPENSSL_VERSION_NUMBER 0x10100001L
+
+#define SSL_R_SHORT_READ 219
+#define SSL_OP_ALL 0
+#define SSL_OP_SINGLE_DH_USE 0
+#define SSL_OP_NO_COMPRESSION 0
+
+#define SSL_OP_NO_SSLv2					0x01000000L
+#define SSL_OP_NO_SSLv3					0x02000000L
+#define SSL_OP_NO_TLSv1					0x04000000L
+
+#define SSL_VERIFY_NONE                 0x00
+#define SSL_VERIFY_PEER                 0x01
+#define SSL_VERIFY_FAIL_IF_NO_PEER_CERT 0x02
+#define SSL_VERIFY_CLIENT_ONCE          0x04
+
+//
+// Implement asio-ssl layer with these three classes in asio::ssl::mbedtls
+//
+namespace asio {
+namespace ssl {
+namespace mbedtls {
+
+class engine;
+class bio;
+class shared_ctx;
+} } } // namespace asio::ssl::mbedtls
+
+//
+// Supply OpenSSL types as aliases to mbedtls classes
+//
+using X509_STORE_CTX=void;
+using BIO=asio::ssl::mbedtls::bio;
+using SSL_CTX=asio::ssl::mbedtls::shared_ctx;
+using SSL=asio::ssl::mbedtls::engine;

components/asio/port/mbedtls/include/mbedtls_bio.hpp

@@ -0,0 +1,113 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once
+
+#include "asio/ssl/context_base.hpp"
+#include "asio/ssl/context.hpp"
+#include "sdkconfig.h"
+
+namespace asio {
+namespace ssl {
+namespace mbedtls {
+
+class bio {
+    static constexpr int BIO_SIZE = CONFIG_ASIO_SSL_BIO_SIZE;
+    static constexpr int BIO_FLAGS_READ = 1;
+    static constexpr int BIO_FLAGS_WRITE = 2;
+
+public:
+    int write(const void *buf, int len)
+    {
+        if (buf == nullptr || len <= 0) {
+            // not an error, just empty operation (as in openssl/bio)
+            return 0;
+        }
+        int remaining = size_ - offset_;
+        if (remaining <= 0) {
+            flags_ |= BIO_FLAGS_WRITE;
+            return -1;
+        }
+        int len_to_write = len > remaining ? remaining : len;
+        std::memcpy(&data_[offset_], buf, len_to_write);
+        offset_ += len_to_write;
+        dlen_ = offset_;
+        if (len_to_write == len) {
+            flags_ &= ~BIO_FLAGS_WRITE;
+        }
+        return len_to_write;
+    }
+
+    int read(void *buf, int len)
+    {
+        if (buf == nullptr || len <= 0) {
+            // not an error, just empty operation (as in openssl/bio)
+            return 0;
+        }
+        int remaining = peer_->dlen_ - peer_->roffset_;
+        if (remaining <= 0) {
+            flags_ |= BIO_FLAGS_READ;
+            return -1;
+        }
+        int len_to_read = remaining > len ? len : remaining;
+        std::memcpy(buf, &peer_->data_[peer_->roffset_], len_to_read);
+        peer_->roffset_ += len_to_read;
+        if (len_to_read == len) {
+            flags_ &= ~BIO_FLAGS_READ;
+        }
+        if (peer_->offset_) {
+            // shift data back to the beginning of the buffer
+            std::memmove(&peer_->data_[0], &peer_->data_[peer_->roffset_], peer_->offset_ - peer_->roffset_);
+            peer_->offset_ -= peer_->roffset_;
+            peer_->roffset_ = 0;
+            peer_->dlen_ = peer_->offset_;
+        }
+        return len_to_read;
+    }
+
+    size_t wpending() const
+    {
+        return dlen_ - roffset_;
+    }
+
+    size_t ctrl_pending()
+    {
+        return peer_->dlen_ - peer_->roffset_;
+    }
+
+    bool should_write() const
+    {
+        return flags_ & BIO_FLAGS_WRITE;
+    }
+
+    bool should_read() const
+    {
+        return flags_ & BIO_FLAGS_READ;
+    }
+
+    static std::pair<std::shared_ptr<bio>, std::shared_ptr<bio>>  new_pair(const char* error_location)
+    {
+        auto b1 = std::shared_ptr<bio>(new (std::nothrow) bio);
+        auto b2 = std::shared_ptr<bio>(new (std::nothrow) bio);
+        if (b1 == nullptr || b2 == nullptr) {
+            throw_alloc_failure(error_location);
+        } else {
+            b1->peer_ = b2;
+            b2->peer_ = b1;
+        }
+        return std::make_pair(b1, b2);
+    }
+
+private:
+    std::array<uint8_t, BIO_SIZE> data_ {};
+    size_t size_ {BIO_SIZE};
+    std::shared_ptr<bio> peer_ {nullptr};
+    int dlen_ {0};
+    size_t offset_ {0};
+    size_t roffset_ {0};
+    size_t flags_ {0};
+};
+
+} } } // namespace asio::ssl::mbedtls

components/asio/port/mbedtls/include/mbedtls_context.hpp

@@ -0,0 +1,105 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once
+
+#include "asio/ssl/context_base.hpp"
+#include "asio/ssl/context.hpp"
+
+namespace asio {
+namespace error {
+
+const asio::error_category& get_mbedtls_category();
+} // namespace error
+
+namespace ssl {
+namespace mbedtls {
+
+void throw_alloc_failure(const char* location);
+
+const char *error_message(int error_code);
+
+enum class container {
+    CERT, CA_CERT, PRIVKEY
+};
+
+template <typename T, typename... Args>
+inline T* create(const char * location, Args &&... args)
+{
+    T* t = new (std::nothrow) T(std::forward<Args>(args)...);
+    if (t == nullptr)
+    {
+        throw_alloc_failure(location);
+    }
+    return t;
+}
+
+class context {
+public:
+    explicit context(context_base::method m): method_(m), options_(0) {}
+
+    const unsigned char *data(container c) const
+    {
+        switch (c) {
+            case container::CERT:
+                return static_cast<const unsigned char *>(cert_chain_.data());
+            case container::CA_CERT:
+                return static_cast<const unsigned char *>(ca_cert_.data());
+            case container::PRIVKEY:
+                return static_cast<const unsigned char *>(private_key_.data());
+        }
+        return nullptr;
+    }
+
+    std::size_t size(container c) const
+    {
+        switch (c) {
+            case container::CERT:
+                return cert_chain_.size();
+            case container::CA_CERT:
+                return ca_cert_.size();
+            case container::PRIVKEY:
+                return private_key_.size();
+        }
+        return 0;
+    }
+
+    context_base::method method_;
+    asio::ssl::context::options options_;
+    const_buffer cert_chain_;
+    const_buffer private_key_;
+    const_buffer ca_cert_;
+};
+
+/**
+ * @brief Wrapper class around SSL_CTX so we can easily create
+ * a shared pointer to the context without throwing the default exception.
+ * This is useful, as we can use asio::detail::throw_error for allocation errors.
+ */
+class shared_ctx {
+public:
+    static SSL_CTX *create(const char* location, context_base::method m)
+    {
+        auto wrapped = asio::ssl::mbedtls::create<shared_ctx>(location, m);
+        if (wrapped->ctx_ == nullptr)
+        {
+            throw_alloc_failure(location);
+        }
+        return wrapped;
+    }
+
+    std::shared_ptr<mbedtls::context> get() const
+    {
+        return ctx_;
+    }
+
+    explicit shared_ctx(context_base::method m)
+        :ctx_(std::shared_ptr<context>(new (std::nothrow) context(m))) { }
+
+private:
+    std::shared_ptr<mbedtls::context> ctx_;
+};
+
+} } } // namespace asio::ssl::mbedtls

components/asio/port/mbedtls/include/mbedtls_engine.hpp

@@ -0,0 +1,293 @@
+//
+// SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once
+
+#include "mbedtls/ssl.h"
+#include "mbedtls/entropy.h"
+#include "mbedtls/ctr_drbg.h"
+#include "mbedtls/error.h"
+#include "mbedtls/esp_debug.h"
+#include "esp_log.h"
+
+namespace asio {
+namespace ssl {
+namespace mbedtls {
+
+const char *error_message(int error_code)
+{
+    static char error_buf[100];
+    mbedtls_strerror(error_code, error_buf, sizeof(error_buf));
+    return error_buf;
+}
+
+void throw_alloc_failure(const char* location)
+{
+    asio::error_code ec( MBEDTLS_ERR_SSL_ALLOC_FAILED, asio::error::get_mbedtls_category());
+    asio::detail::throw_error(ec, location);
+}
+
+namespace error_codes {
+
+bool is_error(int ret)
+{
+    return  ret < 0 && ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE;
+}
+
+static bool want_write(int ret)
+{
+    return  ret == MBEDTLS_ERR_SSL_WANT_WRITE;
+}
+
+static bool want_read(int ret)
+{
+    return  ret == MBEDTLS_ERR_SSL_WANT_READ;
+}
+
+} // namespace error_codes
+
+enum rw_state {
+    IDLE, READING, WRITING, CLOSED
+};
+
+class engine {
+public:
+    explicit engine(std::shared_ptr<context> ctx): ctx_(std::move(ctx)),
+        bio_(bio::new_pair("mbedtls-engine")), state_(IDLE), verify_mode_(0) {}
+
+    void set_verify_mode(asio::ssl::verify_mode mode)
+    {
+        verify_mode_ = mode;
+    }
+
+    bio* ext_bio() const
+    {
+        return bio_.second.get();
+    }
+
+    rw_state get_state() const
+    {
+        return state_;
+    }
+
+    int shutdown()
+    {
+        int ret = mbedtls_ssl_close_notify(&impl_.ssl_);
+        if (ret) {
+            impl::print_error("mbedtls_ssl_close_notify", ret);
+        }
+        state_ = CLOSED;
+        return ret;
+    }
+
+    int connect()
+    {
+        return handshake(true);
+    }
+
+    int accept()
+    {
+        return handshake(false);
+    }
+
+    int write(const void *buffer, int len)
+    {
+        int ret = impl_.write(buffer, len);
+        state_ = ret == len ? IDLE: WRITING;
+        return ret;
+    }
+
+    int read(void *buffer, int len)
+    {
+        int ret = impl_.read(buffer, len);
+        state_ = ret == len ? IDLE: READING;
+        return ret;
+    }
+
+private:
+    int handshake(bool is_client_not_server)
+    {
+        if (impl_.before_handshake()) {
+            impl_.configure(ctx_.get(), is_client_not_server, impl_verify_mode(is_client_not_server));
+        }
+        return do_handshake();
+    }
+
+    static int bio_read(void *ctx, unsigned char *buf, size_t len)
+    {
+        auto bio = static_cast<BIO*>(ctx);
+        int read = bio->read(buf, len);
+        if (read <= 0 && bio->should_read()) {
+            return MBEDTLS_ERR_SSL_WANT_READ;
+        }
+        return read;
+    }
+
+    static int bio_write(void *ctx, const unsigned char *buf, size_t len)
+    {
+        auto bio = static_cast<BIO*>(ctx);
+        int written = bio->write(buf, len);
+        if (written <= 0 && bio->should_write()) {
+            return MBEDTLS_ERR_SSL_WANT_WRITE;
+        }
+        return written;
+    }
+
+    int do_handshake()
+    {
+        int ret = 0;
+        mbedtls_ssl_set_bio(&impl_.ssl_, bio_.first.get(), bio_write, bio_read, nullptr);
+
+        while (impl_.ssl_.MBEDTLS_PRIVATE(state) != MBEDTLS_SSL_HANDSHAKE_OVER) {
+            ret = mbedtls_ssl_handshake_step(&impl_.ssl_);
+
+            if (ret != 0) {
+                if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
+                    impl::print_error("mbedtls_ssl_handshake_step", ret);
+                }
+                if (ret == MBEDTLS_ERR_SSL_WANT_READ) {
+                    state_ = READING;
+                } else if (ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
+                    state_ = WRITING;
+                }
+                break;
+            }
+        }
+        return ret;
+    }
+
+    // Converts OpenSSL verification mode to mbedtls enum
+    int impl_verify_mode(bool is_client_not_server) const
+    {
+        int mode = MBEDTLS_SSL_VERIFY_UNSET;
+        if (is_client_not_server) {
+            if (verify_mode_ & SSL_VERIFY_PEER)
+                mode = MBEDTLS_SSL_VERIFY_REQUIRED;
+            else if (verify_mode_ == SSL_VERIFY_NONE)
+                mode = MBEDTLS_SSL_VERIFY_NONE;
+        } else {
+            if (verify_mode_ & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)
+                mode = MBEDTLS_SSL_VERIFY_REQUIRED;
+            else if (verify_mode_ & SSL_VERIFY_PEER)
+                mode = MBEDTLS_SSL_VERIFY_OPTIONAL;
+            else if (verify_mode_ == SSL_VERIFY_NONE)
+                mode = MBEDTLS_SSL_VERIFY_NONE;
+        }
+        return mode;
+    }
+
+    struct impl {
+        static void print_error(const char* function, int error_code)
+        {
+            constexpr const char *TAG="mbedtls-engine-impl";
+            ESP_LOGE(TAG, "%s() returned -0x%04X", function, -error_code);
+            ESP_LOGI(TAG, "-0x%04X: %s", -error_code, error_message(error_code));
+        }
+
+        bool before_handshake() const
+        {
+            return ssl_.MBEDTLS_PRIVATE(state) == 0;
+        }
+
+        int write(const void *buffer, int len)
+        {
+            int ret = mbedtls_ssl_write(&ssl_, static_cast<const unsigned char *>(buffer), len);
+            if (ret < 0 && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
+                print_error("mbedtls_ssl_write", ret);
+            }
+            return ret;
+        }
+
+        int read(void *buffer, int len)
+        {
+            int ret = mbedtls_ssl_read(&ssl_, static_cast<unsigned char *>(buffer), len);
+            if (ret < 0 && ret != MBEDTLS_ERR_SSL_WANT_READ) {
+                print_error("mbedtls_ssl_read", ret);
+            }
+            return ret;
+        }
+
+        impl()
+        {
+            const unsigned char pers[] = "asio ssl";
+            mbedtls_ssl_init(&ssl_);
+            mbedtls_ssl_config_init(&conf_);
+            mbedtls_ctr_drbg_init(&ctr_drbg_);
+#ifdef CONFIG_MBEDTLS_DEBUG
+            mbedtls_esp_enable_debug_log(&conf_, CONFIG_MBEDTLS_DEBUG_LEVEL);
+#endif
+            mbedtls_entropy_init(&entropy_);
+            mbedtls_ctr_drbg_seed(&ctr_drbg_, mbedtls_entropy_func, &entropy_, pers, sizeof(pers));
+            mbedtls_x509_crt_init(&public_cert_);
+            mbedtls_pk_init(&pk_key_);
+            mbedtls_x509_crt_init(&ca_cert_);
+        }
+
+        bool configure(context *ctx, bool is_client_not_server, int mbedtls_verify_mode)
+        {
+            mbedtls_x509_crt_init(&public_cert_);
+            mbedtls_pk_init(&pk_key_);
+            mbedtls_x509_crt_init(&ca_cert_);
+            int ret = mbedtls_ssl_config_defaults(&conf_, is_client_not_server ? MBEDTLS_SSL_IS_CLIENT: MBEDTLS_SSL_IS_SERVER,
+                                                  MBEDTLS_SSL_TRANSPORT_STREAM, MBEDTLS_SSL_PRESET_DEFAULT);
+            if (ret) {
+                print_error("mbedtls_ssl_config_defaults", ret);
+                return false;
+            }
+            mbedtls_ssl_conf_rng(&conf_, mbedtls_ctr_drbg_random, &ctr_drbg_);
+            mbedtls_ssl_conf_authmode(&conf_, mbedtls_verify_mode);
+            if (ctx->cert_chain_.size() > 0 && ctx->private_key_.size() > 0) {
+                ret = mbedtls_x509_crt_parse(&public_cert_, ctx->data(container::CERT), ctx->size(container::CERT));
+                if (ret < 0) {
+                    print_error("mbedtls_x509_crt_parse", ret);
+                    return false;
+                }
+                ret = mbedtls_pk_parse_key(&pk_key_, ctx->data(container::PRIVKEY), ctx->size(container::PRIVKEY),
+                                           nullptr, 0, mbedtls_ctr_drbg_random, &ctr_drbg_);
+                if (ret < 0) {
+                    print_error("mbedtls_pk_parse_keyfile", ret);
+                    return false;
+                }
+                ret = mbedtls_ssl_conf_own_cert(&conf_, &public_cert_, &pk_key_);
+                if (ret) {
+                    print_error("mbedtls_ssl_conf_own_cert", ret);
+                    return false;
+                }
+            }
+
+            if (ctx->ca_cert_.size() > 0) {
+                ret = mbedtls_x509_crt_parse(&ca_cert_, ctx->data(container::CA_CERT), ctx->size(container::CA_CERT));
+                if (ret < 0) {
+                    print_error("mbedtls_x509_crt_parse", ret);
+                    return false;
+                }
+                mbedtls_ssl_conf_ca_chain(&conf_, &ca_cert_, nullptr);
+            } else {
+                mbedtls_ssl_conf_ca_chain(&conf_, nullptr, nullptr);
+            }
+            ret = mbedtls_ssl_setup(&ssl_, &conf_);
+            if (ret) {
+                print_error("mbedtls_ssl_setup", ret);
+                return false;
+            }
+            return true;
+        }
+        mbedtls_ssl_context ssl_{};
+        mbedtls_entropy_context entropy_{};
+        mbedtls_ctr_drbg_context ctr_drbg_{};
+        mbedtls_ssl_config conf_{};
+        mbedtls_x509_crt public_cert_{};
+        mbedtls_pk_context pk_key_{};
+        mbedtls_x509_crt ca_cert_{};
+    };
+
+    impl impl_{};
+    std::shared_ptr<context> ctx_;
+    std::pair<std::shared_ptr<bio>, std::shared_ptr<bio>> bio_;
+    enum rw_state state_;
+    asio::ssl::verify_mode verify_mode_;
+};
+
+} } } // namespace asio::ssl::mbedtls

components/asio/port/mbedtls/include/mbedtls_error.hpp

@@ -0,0 +1,55 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once
+
+#include "asio/detail/config.hpp"
+#include "asio/ssl/error.hpp"
+#include "asio/ssl/detail/openssl_init.hpp"
+#include "mbedtls_context.hpp"
+
+namespace asio {
+namespace error {
+namespace detail {
+
+class mbedtls_category : public asio::error_category
+{
+public:
+    const char* name() const ASIO_ERROR_CATEGORY_NOEXCEPT
+    {
+        return "asio.ssl";
+    }
+
+    std::string message(int value) const
+    {
+        const char* s = asio::ssl::mbedtls::error_message(value);
+        return s ? s : "asio.mbedtls error";
+    }
+};
+
+} // namespace detail
+
+const asio::error_category& get_mbedtls_category()
+{
+    static detail::mbedtls_category instance;
+    return instance;
+}
+
+const asio::error_category& get_ssl_category()
+{
+    return asio::error::get_mbedtls_category();
+}
+
+} // namespace error
+
+namespace ssl {
+namespace error {
+
+const asio::error_category& get_stream_category()
+{
+    return asio::error::get_mbedtls_category();
+}
+
+} } } // namespace asio::ssl::error

components/asio/port/mbedtls/include/openssl/conf.h

@@ -0,0 +1,6 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once

components/asio/port/mbedtls/include/openssl/dh.h

@@ -0,0 +1,6 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once

components/asio/port/mbedtls/include/openssl/err.h

@@ -0,0 +1,6 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once

components/asio/port/mbedtls/include/openssl/rsa.h

@@ -0,0 +1,6 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once

components/asio/port/mbedtls/include/openssl/ssl.h

@@ -0,0 +1,8 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once
+
+#include "openssl_stub.hpp"

components/asio/port/mbedtls/include/openssl/x509v3.h

@@ -0,0 +1,6 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+#pragma once

components/asio/port/mbedtls/src/mbedtls_context.cpp

@@ -0,0 +1,115 @@
+//
+// SPDX-FileCopyrightText: 2005 Voipster / Indrek dot Juhani at voipster dot com
+// SPDX-FileCopyrightText: 2005-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+// SPDX-FileContributor: 2021 Espressif Systems (Shanghai) CO LTD
+//
+
+#include "asio/detail/config.hpp"
+#include "openssl_stub.hpp"
+#include <cstring>
+#include "asio/detail/throw_error.hpp"
+#include "asio/error.hpp"
+#include "asio/ssl/context.hpp"
+#include "asio/ssl/error.hpp"
+#include "mbedtls_context.hpp"
+
+
+namespace asio {
+namespace ssl {
+
+
+context::context(context::method m)
+        : handle_(0)
+{
+    handle_ = mbedtls::shared_ctx::create("mbedtls-context", m);
+    set_options(no_compression);
+}
+
+context::context(context&& other)
+{
+    handle_ = other.handle_;
+    other.handle_ = 0;
+}
+
+context& context::operator=(context&& other)
+{
+    context tmp(ASIO_MOVE_CAST(context)(*this));
+    handle_ = other.handle_;
+    other.handle_ = 0;
+    return *this;
+}
+
+context::~context()
+{
+    delete handle_;
+}
+
+context::native_handle_type context::native_handle()
+{
+    return handle_;
+}
+
+void context::set_options(context::options o)
+{
+    asio::error_code ec;
+    set_options(o, ec);
+    asio::detail::throw_error(ec, "set_options");
+}
+
+ASIO_SYNC_OP_VOID context::set_options(
+        context::options o, asio::error_code& ec)
+{
+    handle_->get()->options_ = o;
+    ec = asio::error_code();
+    ASIO_SYNC_OP_VOID_RETURN(ec);
+}
+
+void context::add_certificate_authority(const const_buffer& ca)
+{
+    asio::error_code ec;
+    add_certificate_authority(ca, ec);
+    asio::detail::throw_error(ec, "add_certificate_authority");
+}
+
+ASIO_SYNC_OP_VOID context::add_certificate_authority(
+        const const_buffer& ca, asio::error_code& ec)
+{
+    handle_->get()->ca_cert_ = ca;
+    ASIO_SYNC_OP_VOID_RETURN(asio::error_code());
+}
+
+void context::use_certificate_chain(const const_buffer& chain)
+{
+    asio::error_code ec;
+    use_certificate_chain(chain, ec);
+    asio::detail::throw_error(ec, "use_certificate_chain");
+}
+
+ASIO_SYNC_OP_VOID context::use_certificate_chain(
+        const const_buffer& chain, asio::error_code& ec)
+{
+    handle_->get()->cert_chain_ = chain;
+    ASIO_SYNC_OP_VOID_RETURN(asio::error_code());
+}
+
+void context::use_private_key(
+        const const_buffer& private_key, context::file_format format)
+{
+    asio::error_code ec;
+    use_private_key(private_key, format, ec);
+    asio::detail::throw_error(ec, "use_private_key");
+}
+
+ASIO_SYNC_OP_VOID context::use_private_key(
+        const const_buffer& private_key, context::file_format format,
+        asio::error_code& ec)
+{
+    handle_->get()->private_key_ = private_key;
+    ASIO_SYNC_OP_VOID_RETURN(asio::error_code());
+}
+
+} // namespace ssl
+} // namespace asio

components/asio/port/mbedtls/src/mbedtls_engine.cpp

@@ -0,0 +1,208 @@
+//
+// SPDX-FileCopyrightText: 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// SPDX-License-Identifier: BSL-1.0
+//
+// SPDX-FileContributor: 2021 Espressif Systems (Shanghai) CO LTD
+//
+
+#include "asio/detail/config.hpp"
+#include "openssl_stub.hpp"
+#include "asio/detail/throw_error.hpp"
+#include "asio/error.hpp"
+#include "asio/ssl/detail/engine.hpp"
+#include "asio/ssl/error.hpp"
+#include "asio/ssl/verify_context.hpp"
+#include "mbedtls_context.hpp"
+#include "mbedtls_bio.hpp"
+#include "mbedtls_error.hpp"
+#include "mbedtls_engine.hpp"
+
+
+namespace asio {
+namespace ssl {
+namespace detail {
+
+
+engine::engine(SSL_CTX* context)
+        : ssl_(nullptr)
+{
+    ssl_ = mbedtls::create<mbedtls::engine>("mbedtls-engine", context->get());
+}
+
+engine::~engine()
+{
+    delete ssl_;
+}
+
+SSL* engine::native_handle()
+{
+    return ssl_;
+}
+
+asio::error_code engine::set_verify_mode(
+        verify_mode v, asio::error_code& ec)
+{
+    ssl_->set_verify_mode(v);
+    return {};
+}
+
+engine::want engine::handshake(
+        stream_base::handshake_type type, asio::error_code& ec)
+{
+    return perform((type == asio::ssl::stream_base::client)
+                   ? &engine::do_connect : &engine::do_accept, 0, 0, ec, 0);
+}
+
+engine::want engine::shutdown(asio::error_code& ec)
+{
+    return perform(&engine::do_shutdown, 0, 0, ec, 0);
+}
+
+engine::want engine::write(const asio::const_buffer& data,
+                           asio::error_code& ec, std::size_t& bytes_transferred)
+{
+    if (data.size() == 0)
+    {
+        ec = asio::error_code();
+        return engine::want_nothing;
+    }
+
+    return perform(&engine::do_write,
+                   const_cast<void*>(data.data()),
+                   data.size(), ec, &bytes_transferred);
+}
+
+engine::want engine::read(const asio::mutable_buffer& data,
+                          asio::error_code& ec, std::size_t& bytes_transferred)
+{
+    if (data.size() == 0)
+    {
+        ec = asio::error_code();
+        return engine::want_nothing;
+    }
+
+    return perform(&engine::do_read, data.data(),
+                   data.size(), ec, &bytes_transferred);
+}
+
+asio::mutable_buffer engine::get_output(
+        const asio::mutable_buffer& data)
+{
+    int length = ssl_->ext_bio()->read(data.data(), static_cast<int>(data.size()));
+
+    return asio::buffer(data,
+                        length > 0 ? static_cast<std::size_t>(length) : 0);
+}
+
+asio::const_buffer engine::put_input(
+        const asio::const_buffer& data)
+{
+    int length = ssl_->ext_bio()->write(data.data(), static_cast<int>(data.size()));
+
+    return asio::buffer(data +
+                        (length > 0 ? static_cast<std::size_t>(length) : 0));
+}
+
+const asio::error_code& engine::map_error_code(
+        asio::error_code& ec) const
+{
+    // We only want to map the error::eof code.
+    if (ec != asio::error::eof)
+        return ec;
+
+    // If there's data yet to be read, it's an error.
+    if (ssl_->ext_bio()->wpending())
+    {
+        ec = asio::ssl::error::stream_truncated;
+        return ec;
+    }
+
+    // Otherwise, the peer should have negotiated a proper shutdown.
+    if (ssl_->shutdown() != 0)
+    {
+        ec = asio::ssl::error::stream_truncated;
+    }
+
+    return ec;
+}
+
+// This is a simplified implementation of a generic ssl io operation
+// original implementation using openssl's SSL object is in asio/include/asio/ssl/detail/impl/engine.ipp
+engine::want engine::perform(int (engine::* op)(void*, std::size_t),
+                             void* data, std::size_t length, asio::error_code& ec,
+                             std::size_t* bytes_transferred)
+{
+    std::size_t pending_output_before = ssl_->ext_bio()->ctrl_pending();
+    int result = (this->*op)(data, length);
+
+    std::size_t pending_output_after = ssl_->ext_bio()->ctrl_pending();
+
+    if (mbedtls::error_codes::is_error(result))
+    {
+        ec = asio::error_code(result, asio::error::get_mbedtls_category());
+        return pending_output_after > pending_output_before ? want_output : want_nothing;
+    }
+
+    if (result == 0)
+    {
+        return pending_output_after > pending_output_before
+               ? want_output : want_nothing;
+    }
+
+    if (result > 0 && bytes_transferred)
+        *bytes_transferred = static_cast<std::size_t>(result);
+
+    if (mbedtls::error_codes::want_write(result))
+    {
+        ec = asio::error_code();
+        return want_output_and_retry;
+    }
+    else if (pending_output_after > pending_output_before)
+    {
+        ec = asio::error_code();
+        return result > 0 ? want_output : want_output_and_retry;
+    }
+    else if (mbedtls::error_codes::want_read(result))
+    {
+        ec = asio::error_code();
+        return want_input_and_retry;
+    }
+    else if (ssl_->get_state() == mbedtls::CLOSED)
+    {
+        ec = asio::error::eof;
+        return want_nothing;
+    }
+
+    ec = asio::error_code();
+    return want_nothing;
+}
+
+int engine::do_accept(void*, std::size_t)
+{
+    return ssl_->accept();
+}
+
+int engine::do_connect(void*, std::size_t)
+{
+    return ssl_->connect();
+}
+
+int engine::do_shutdown(void*, std::size_t)
+{
+    return ssl_->shutdown();
+}
+
+int engine::do_read(void* data, std::size_t length)
+{
+    return ssl_->read(data, length < INT_MAX ? static_cast<int>(length) : INT_MAX);
+}
+
+int engine::do_write(void* data, std::size_t length)
+{
+    return ssl_->write(data, length < INT_MAX ? static_cast<int>(length) : INT_MAX);
+}
+
+} // namespace detail
+} // namespace ssl
+} // namespace asio

components/asio/port/src/asio_ssl_impl.cpp

@@ -0,0 +1,20 @@
+//
+// SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+#include "asio/detail/config.hpp"
+#include "asio/ssl/detail/openssl_init.hpp"
+
+namespace asio {
+namespace ssl {
+namespace detail {
+
+// No OpenSSL in this implementation, instance is nullptr
+asio::detail::shared_ptr<openssl_init_base::do_init> openssl_init_base::instance()
+{
+    return nullptr;
+}
+
+} } } // namespace asio::ssl::detail

components/esp_modem/examples/modem_console/main/console_helper.hpp

@@ -10,6 +10,7 @@
 #pragma once
 
 #include <vector>
+#include <string>
 #include <algorithm>
 #include <functional>
 #include <esp_console.h>

components/esp_modem/examples/simple_cmux_client/main/simple_cmux_client_main.cpp

@@ -87,10 +87,10 @@ extern "C" void app_main(void)
     }
 #endif
 
-    if (dce->set_mode(esp_modem::modem_mode::CMUX_MODE) && dce->set_mode(esp_modem::modem_mode::DATA_MODE)) {
+    if (dce->set_mode(esp_modem::modem_mode::CMUX_MODE)) {
         std::cout << "Modem has correctly entered multiplexed command/data mode" << std::endl;
     } else {
-        ESP_LOGE(TAG, "Failed to configure desired mode... exiting");
+        ESP_LOGE(TAG, "Failed to configure multiplexed command mode... exiting");
         return;
     }
 

components/esp_modem/idf_component.yml

@@ -1,4 +1,4 @@
-version: "0.1.16"
+version: "0.1.17"
 description: esp modem
 url: https://github.com/espressif/esp-protocols/tree/master/components/esp_modem
 dependencies:

components/esp_modem/include/cxx_include/esp_modem_buffer.hpp

@@ -0,0 +1,50 @@
+// Copyright 2022 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+namespace esp_modem {
+
+/**
+ * Common unique buffer, which is transferable between DTE and CMUX
+ *
+ */
+struct unique_buffer {
+    explicit unique_buffer(size_t size);
+    unique_buffer (unique_buffer const&) = delete;
+    unique_buffer& operator=(unique_buffer const&) = delete;
+    unique_buffer(unique_buffer&& other) noexcept
+    {
+        data = std::move(other.data);
+        size = other.size;
+        consumed = 0;
+    }
+    unique_buffer& operator=(unique_buffer&& other) noexcept
+    {
+        if (&other == this) {
+            return *this;
+        }
+        data = std::move(other.data);
+        size = other.size;
+        consumed = 0;
+        return *this;
+    }
+    [[nodiscard]] uint8_t *get() const { return data.get(); }
+
+    std::unique_ptr<uint8_t[]> data;
+    size_t size{};
+    size_t consumed{};
+};
+
+}

components/esp_modem/include/cxx_include/esp_modem_cmux.hpp

@@ -15,6 +15,7 @@
 #pragma once
 
 #include "esp_modem_terminal.hpp"
+#include "cxx_include/esp_modem_buffer.hpp"
 
 namespace esp_modem {
 
@@ -54,8 +55,8 @@ class CMuxInstance;
  */
 class CMux {
 public:
-    explicit CMux(std::unique_ptr<Terminal> t, std::unique_ptr<uint8_t[]> b, size_t buff_size):
-        term(std::move(t)), payload_start(nullptr), total_payload_size(0), buffer_size(buff_size), buffer(std::move(b))  {}
+    explicit CMux(std::shared_ptr<Terminal> t, unique_buffer&& b):
+        term(std::move(t)), payload_start(nullptr), total_payload_size(0), buffer(std::move(b))  {}
     ~CMux() = default;
 
     /**
@@ -64,6 +65,19 @@ public:
      */
     [[nodiscard]] bool init();
 
+    /**
+     * @brief Closes and deinits CMux protocol
+     * @return true on success
+     */
+    [[nodiscard]] bool deinit();
+
+    /**
+     * @brief   Ejects the attached terminal and buffer,
+     * so they could be used as traditional command/data DTE's
+     * @return  pair of the original terminal and buffer
+     */
+    std::pair<std::shared_ptr<Terminal>, unique_buffer> detach();
+
     /**
      * @brief Sets read callback for the appropriate terminal
      * @param inst Index of the terminal
@@ -84,7 +98,8 @@ private:
     static uint8_t fcs_crc(const uint8_t frame[6]);     /*!< Utility to calculate FCS CRC */
     void data_available(uint8_t *data, size_t len);     /*!< Called when valid data available */
     void send_sabm(size_t i);                           /*!< Sending initial SABM */
-    bool on_cmux(uint8_t *data, size_t len);            /*!< Called from terminal layer when raw CMUX protocol data available */
+    void send_disconnect(size_t i);                     /*!< Sending closing request for each virtual or control terminal */
+    bool on_cmux_data(uint8_t *data, size_t len);       /*!< Called from terminal layer when raw CMUX protocol data available */
 
     struct CMuxFrame;                                   /*!< Forward declare the Frame struct, used in protocol decoders */
     /**
@@ -100,7 +115,7 @@ private:
     bool on_footer(CMuxFrame &frame);
 
     std::function<bool(uint8_t *data, size_t len)> read_cb[MAX_TERMINALS_NUM];  /*!< Function pointers to read callbacks */
-    std::unique_ptr<Terminal> term;                   /*!< The original terminal */
+    std::shared_ptr<Terminal> term;                   /*!< The original terminal */
     cmux_state state;                                 /*!< CMux protocol state */
 
     /**
@@ -117,10 +132,9 @@ private:
     int sabm_ack;
 
     /**
-     * Processing buffer size and pointer
+     * Processing unique buffer (reused and transferred from it's parent DTE)
      */
-    size_t buffer_size;
-    std::unique_ptr<uint8_t[]> buffer;
+    unique_buffer buffer;
 
     Lock lock;
 };

components/esp_modem/include/cxx_include/esp_modem_dce.hpp

@@ -40,6 +40,7 @@ public:
     modem_mode get();
 
 private:
+    bool set_unsafe(DTE *dte, ModuleIf *module, Netif &netif, modem_mode m);
     modem_mode mode;
 
 };

components/esp_modem/include/cxx_include/esp_modem_dce_module.hpp

@@ -79,8 +79,17 @@ public:
             }
             return true;
         } else if (mode == modem_mode::COMMAND_MODE) {
-            Task::Delay(1000); // Mandatory 1s pause
-            return set_command_mode() == command_result::OK;
+            Task::Delay(1000); // Mandatory 1s pause before
+            int retry = 0;
+            while (retry++ < 3) {
+                if (set_command_mode() == command_result::OK)
+                    return true;
+                Task::Delay(1000); // Mandatory 1s pause after escape
+                if (sync() == command_result::OK)
+                    return true;
+                Task::Delay(1000); // Mandatory 1s pause before escape
+            }
+            return false;
         } else if (mode == modem_mode::CMUX_MODE) {
             return set_cmux() == command_result::OK;
         }

components/esp_modem/include/cxx_include/esp_modem_dte.hpp

@@ -15,18 +15,20 @@
 #pragma once
 
 #include <memory>
+#include <utility>
 #include <cstddef>
 #include <cstdint>
-#include <utility>
 #include "cxx_include/esp_modem_primitives.hpp"
 #include "cxx_include/esp_modem_terminal.hpp"
-#include "cxx_include/esp_modem_cmux.hpp"
 #include "cxx_include/esp_modem_types.hpp"
+#include "cxx_include/esp_modem_buffer.hpp"
 
 struct esp_modem_dte_config;
 
 namespace esp_modem {
 
+class CMux;
+
 /**
  * @defgroup ESP_MODEM_DTE
  * @brief Definition of DTE and related classes
@@ -94,21 +96,27 @@ public:
      */
     command_result command(const std::string &command, got_line_cb got_line, uint32_t time_ms, char separator) override;
 
+protected:
+    /**
+     * @brief Allows for locking the DTE
+     */
+    void lock()     { internal_lock.lock();   }
+    void unlock()   { internal_lock.unlock(); }
+    friend class Scoped<DTE>;                               /*!< Declaring "Scoped<DTE> lock(dte)" locks this instance */
 private:
     static const size_t GOT_LINE = SignalGroup::bit0;       /*!< Bit indicating response available */
 
-    [[nodiscard]] bool setup_cmux();                         /*!< Internal setup of CMUX mode */
+    [[nodiscard]] bool setup_cmux();                        /*!< Internal setup of CMUX mode */
+    [[nodiscard]] bool exit_cmux();                         /*!< Exit of CMUX mode */
 
-    Lock lock{};                                            /*!< Locks DTE operations */
-    size_t buffer_size;                                      /*!< Size of available DTE buffer */
-    size_t consumed;                                         /*!< Indication of already processed portion in DTE buffer */
-    std::unique_ptr<uint8_t[]> buffer;                       /*!< DTE buffer */
-    std::unique_ptr<Terminal> term;                          /*!< Primary terminal for this DTE */
-    Terminal *command_term;                                  /*!< Reference to the terminal used for sending commands */
-    std::unique_ptr<Terminal> other_term;                    /*!< Secondary terminal for this DTE */
-    modem_mode mode;                                         /*!< DTE operation mode */
+    Lock internal_lock{};                                   /*!< Locks DTE operations */
+    unique_buffer buffer;                                   /*!< DTE buffer */
+    std::shared_ptr<CMux> cmux_term;                        /*!< Primary terminal for this DTE */
+    std::shared_ptr<Terminal> command_term;                 /*!< Reference to the terminal used for sending commands */
+    std::shared_ptr<Terminal> data_term;                    /*!< Secondary terminal for this DTE */
+    modem_mode mode;                                        /*!< DTE operation mode */
     SignalGroup signal;                                     /*!< Event group used to signal request-response operations */
-    std::function<bool(uint8_t *data, size_t len)> on_data;  /*!< on data callback for current terminal */
+    std::function<bool(uint8_t *data, size_t len)> on_data; /*!< on data callback for current terminal */
 };
 
 /**

components/esp_modem/include/cxx_include/esp_modem_primitives.hpp

@@ -46,7 +46,7 @@ private:
 using TaskT = TaskHandle_t;
 using SignalT = EventGroupHandle_t;
 #else
-using Lock = std::mutex;
+using Lock = std::recursive_mutex;
 struct SignalGroupInternal;
 using SignalT = std::unique_ptr<SignalGroupInternal>;
 using TaskT = std::thread;

components/esp_modem/include/esp_modem_c_api_types.h

@@ -39,6 +39,7 @@ typedef enum esp_modem_dce_mode
 {
     ESP_MODEM_MODE_COMMAND,  /**< Default mode after modem startup, used for sending AT commands */
     ESP_MODEM_MODE_DATA,     /**< Used for switching to PPP mode for the modem to connect to a network */
+    ESP_MODEM_MODE_CMUX,     /**< Multiplexed terminal mode */
 } esp_modem_dce_mode_t;
 
 /**

components/esp_modem/src/esp_modem_c_api.cpp

@@ -125,6 +125,13 @@ extern "C" esp_err_t esp_modem_set_mode(esp_modem_dce_t *dce_wrap, esp_modem_dce
         dce_wrap->dce->set_data();
     } else if (mode == ESP_MODEM_MODE_COMMAND) {
         dce_wrap->dce->exit_data();
+    } else if (mode == ESP_MODEM_MODE_CMUX) {
+        if (dce_wrap->dce->set_mode(modem_mode::CMUX_MODE) &&
+            // automatically switch to data mode for the primary terminal
+            dce_wrap->dce->set_mode(modem_mode::DATA_MODE)) {
+            return ESP_OK;
+        }
+        return ESP_FAIL;
     } else {
         return ESP_ERR_NOT_SUPPORTED;
     }

components/esp_modem/src/esp_modem_cmux.cpp

@@ -78,6 +78,21 @@ uint8_t CMux::fcs_crc(const uint8_t frame[6])
     return crc;
 }
 
+void CMux::send_disconnect(size_t i)
+{
+    if (i == 0) {   // control terminal
+        uint8_t frame[] = {
+                SOF_MARKER, 0x3, 0xFF, 0x5, 0xC3, 0x1, 0xE7, SOF_MARKER };
+        term->write(frame, 8);
+    } else {        // separate virtual terminal
+        uint8_t frame[] = {
+                SOF_MARKER, 0x3, FT_DISC | PF, 0x1, 0, SOF_MARKER };
+        frame[1] |= i << 2;
+        frame[4] = 0xFF - fcs_crc(frame);
+        term->write(frame, sizeof(frame));
+    }
+}
+
 void CMux::send_sabm(size_t i)
 {
     uint8_t frame[6];
@@ -127,6 +142,9 @@ void CMux::data_available(uint8_t *data, size_t len)
             read_cb[virtual_term](payload_start, total_payload_size);
 #endif
         }
+    } else if (type == 0xFF && dlci == 0) { // notify the internal DISC command
+        Scoped<Lock> l(lock);
+        sabm_ack = dlci;
     }
 }
 
@@ -187,10 +205,22 @@ bool CMux::on_header(CMuxFrame &frame)
     }
     size_t payload_offset = std::min(frame.len, 4 - frame_header_offset);
     memcpy(frame_header + frame_header_offset, frame.ptr, payload_offset);
-    frame_header_offset += payload_offset;
+    if ((frame_header[3] & 1) == 0) {
+        if (frame_header_offset + frame.len <= 4) {
+            frame_header_offset += frame.len;
+            return false; // need read more
+        }
+        payload_offset = std::min(frame.len, 5 - frame_header_offset);
+        memcpy(frame_header + frame_header_offset, frame.ptr, payload_offset);
+        payload_len = frame_header[4] << 7;
+        frame_header_offset += payload_offset - 1; // rewind frame_header back to hold only 6 bytes size
+    } else {
+        payload_len = 0;
+        frame_header_offset += payload_offset;
+    }
     dlci = frame_header[1] >> 2;
     type = frame_header[2];
-    payload_len = (frame_header[3] >> 1);
+    payload_len += (frame_header[3] >> 1);
     frame.advance(payload_offset);
     state = cmux_state::PAYLOAD;
     return true;
@@ -242,11 +272,11 @@ bool CMux::on_footer(CMuxFrame &frame)
     return true;
 }
 
-bool CMux::on_cmux(uint8_t *data, size_t actual_len)
+bool CMux::on_cmux_data(uint8_t *data, size_t actual_len)
 {
     if (!data) {
 #ifdef DEFRAGMENT_CMUX_PAYLOAD
-        auto data_to_read = buffer_size - 128; // keep 128 (max CMUX payload) backup buffer)
+        auto data_to_read = buffer.size - 128; // keep 128 (max CMUX payload) backup buffer)
         if (payload_start) {
             data = payload_start + total_payload_size;
             data_to_read = payload_len + 2;
@@ -293,12 +323,48 @@ bool CMux::on_cmux(uint8_t *data, size_t actual_len)
     return true;
 }
 
+bool CMux::deinit()
+{
+    int timeout = 0;
+    sabm_ack = -1;
+    // First disconnect all (2) virtual terminals
+    for (size_t i = 1; i < 3; i++) {
+        send_disconnect(i);
+        while (true) {
+            usleep(10'000);
+            Scoped<Lock> l(lock);
+            if (sabm_ack == i) {
+                sabm_ack = -1;
+                break;
+            }
+            if (timeout++ > 100) {
+                return false;
+            }
+        }
+    }
+    sabm_ack = -1;
+    // Then disconnect the control terminal
+    send_disconnect(0);
+    while (true) {
+        usleep(10'000);
+        Scoped<Lock> l(lock);
+        if (sabm_ack == 0) {
+            break;
+        }
+        if (timeout++ > 100) {
+            return false;
+        }
+    }
+    term->set_read_cb(nullptr);
+    return true;
+}
+
 bool CMux::init()
 {
     frame_header_offset = 0;
     state = cmux_state::INIT;
     term->set_read_cb([this](uint8_t *data, size_t len) {
-        this->on_cmux(data, len);
+        this->on_cmux_data(data, len);
         return false;
     });
 
@@ -358,3 +424,8 @@ void CMux::set_read_cb(int inst, std::function<bool(uint8_t *, size_t)> f)
         read_cb[inst] = std::move(f);
     }
 }
+
+std::pair<std::shared_ptr<Terminal>, unique_buffer> CMux::detach()
+{
+    return std::make_pair(std::move(term), std::move(buffer));
+}

components/esp_modem/src/esp_modem_dce.cpp

@@ -12,7 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#include <list>
 #include <unistd.h>
+#include <cstring>
 
 #include "cxx_include/esp_modem_dte.hpp"
 #include "cxx_include/esp_modem_dce.hpp"
@@ -20,33 +22,77 @@
 
 namespace esp_modem {
 
-
+/**
+ * Set mode while the entire DTE is locked
+*/
 bool DCE_Mode::set(DTE *dte, ModuleIf *device, Netif &netif, modem_mode m)
+{
+    Scoped<DTE> lock(*dte);
+    return set_unsafe(dte, device, netif, m);
+}
+
+/**
+ * state machine:
+ *
+ * COMMAND_MODE <----> DATA_MODE
+ * COMMAND_MODE <----> CMUX_MODE
+ *
+ * UNDEF <----> any
+ */
+bool DCE_Mode::set_unsafe(DTE *dte, ModuleIf *device, Netif &netif, modem_mode m)
 {
     switch (m) {
     case modem_mode::UNDEF:
         break;
     case modem_mode::COMMAND_MODE:
-        if (mode == modem_mode::COMMAND_MODE) {
-            return false;
+        {
+            if (mode == modem_mode::COMMAND_MODE) {
+                return false;
+            }
+            if (mode == modem_mode::CMUX_MODE) {
+                netif.stop();
+                netif.wait_until_ppp_exits();
+                if (!dte->set_mode(modem_mode::COMMAND_MODE)) {
+                    return false;
+                }
+                mode = m;
+                return true;
+            }
+            netif.stop();
+            auto signal = std::make_shared<SignalGroup>();
+            std::weak_ptr<SignalGroup> weak_signal = signal;
+            dte->set_read_cb([weak_signal](uint8_t *data, size_t len) -> bool {
+                if (memchr(data, '\n', len)) {
+                    ESP_LOG_BUFFER_HEXDUMP("esp-modem: debug_data", data, len, ESP_LOG_DEBUG);
+                    const auto pass = std::list<std::string_view>({"NO CARRIER", "DISCONNECTED"});
+                    std::string_view response((char *) data, len);
+                    for (auto &it : pass)
+                        if (response.find(it) != std::string::npos) {
+                            if (auto signal = weak_signal.lock())
+                                signal->set(1);
+                            return true;
+                        }
+                }
+                return false;
+            });
+            netif.wait_until_ppp_exits();
+            if (!signal->wait(1, 2000)) {
+                if (!device->set_mode(modem_mode::COMMAND_MODE)) {
+                    mode = modem_mode::UNDEF;
+                    return false;
+                }
+            }
+            dte->set_read_cb(nullptr);
+            if (!dte->set_mode(modem_mode::COMMAND_MODE)) {
+                mode = modem_mode::UNDEF;
+                return false;
+            }
+            mode = m;
+            return true;
         }
-        netif.stop();
-        if (!device->set_mode(modem_mode::COMMAND_MODE)) {
-            return false;
-        }
-        dte->set_read_cb([&](uint8_t *data, size_t len) -> bool {
-            ESP_LOG_BUFFER_HEXDUMP("esp-modem: debug_data", data, len, ESP_LOG_INFO);
-            return false;
-        });
-        netif.wait_until_ppp_exits();
-        dte->set_read_cb(nullptr);
-        if (!dte->set_mode(modem_mode::COMMAND_MODE)) {
-            return false;
-        }
-        mode = m;
-        return true;
+        break;
     case modem_mode::DATA_MODE:
-        if (mode == modem_mode::DATA_MODE) {
+        if (mode == modem_mode::DATA_MODE || mode == modem_mode::CMUX_MODE) {
             return false;
         }
         if (!device->setup_data_mode()) {
@@ -71,7 +117,17 @@ bool DCE_Mode::set(DTE *dte, ModuleIf *device, Netif &netif, modem_mode m)
         if (!dte->set_mode(modem_mode::CMUX_MODE)) {
             return false;
         }
-        mode = modem_mode::COMMAND_MODE;
+        mode = modem_mode::CMUX_MODE;
+        if (!device->setup_data_mode()) {
+            return false;
+        }
+        if (!device->set_mode(modem_mode::DATA_MODE)) {
+            return false;
+        }
+        if (!dte->set_mode(modem_mode::DATA_MODE)) {
+            return false;
+        }
+        netif.start();
         return true;
     }
     return false;

components/esp_modem/src/esp_modem_dte.cpp

@@ -15,6 +15,7 @@
 #include <cstring>
 #include "esp_log.h"
 #include "cxx_include/esp_modem_dte.hpp"
+#include "cxx_include/esp_modem_cmux.hpp"
 #include "esp_modem_config.h"
 
 using namespace esp_modem;
@@ -22,36 +23,34 @@ using namespace esp_modem;
 static const size_t dte_default_buffer_size = 1000;
 
 DTE::DTE(const esp_modem_dte_config *config, std::unique_ptr<Terminal> terminal):
-    buffer_size(config->dte_buffer_size), consumed(0),
-    buffer(std::make_unique<uint8_t[]>(buffer_size)),
-    term(std::move(terminal)), command_term(term.get()), other_term(nullptr),
+    buffer(config->dte_buffer_size),
+    cmux_term(nullptr), command_term(std::move(terminal)), data_term(command_term),
     mode(modem_mode::UNDEF) {}
 
 DTE::DTE(std::unique_ptr<Terminal> terminal):
-    buffer_size(dte_default_buffer_size), consumed(0),
-    buffer(std::make_unique<uint8_t[]>(buffer_size)),
-    term(std::move(terminal)), command_term(term.get()), other_term(nullptr),
+    buffer(dte_default_buffer_size),
+    cmux_term(nullptr), command_term(std::move(terminal)), data_term(command_term),
     mode(modem_mode::UNDEF) {}
 
 command_result DTE::command(const std::string &command, got_line_cb got_line, uint32_t time_ms, const char separator)
 {
-    Scoped<Lock> l(lock);
+    Scoped<Lock> l(internal_lock);
     command_result res = command_result::TIMEOUT;
     command_term->set_read_cb([&](uint8_t *data, size_t len) {
         if (!data) {
             data = buffer.get();
-            len = command_term->read(data + consumed, buffer_size - consumed);
+            len = command_term->read(data + buffer.consumed, buffer.size - buffer.consumed);
         } else {
-            consumed = 0; // if the underlying terminal contains data, we cannot fragment
+            buffer.consumed = 0; // if the underlying terminal contains data, we cannot fragment
         }
-        if (memchr(data + consumed, separator, len)) {
-            res = got_line(data, consumed + len);
+        if (memchr(data + buffer.consumed, separator, len)) {
+            res = got_line(data, buffer.consumed + len);
             if (res == command_result::OK || res == command_result::FAIL) {
                 signal.set(GOT_LINE);
                 return true;
             }
         }
-        consumed += len;
+        buffer.consumed += len;
         return false;
     });
     command_term->write((uint8_t *)command.c_str(), command.length());
@@ -59,7 +58,7 @@ command_result DTE::command(const std::string &command, got_line_cb got_line, ui
     if (got_lf && res == command_result::TIMEOUT) {
         throw_if_esp_fail(ESP_ERR_INVALID_STATE);
     }
-    consumed = 0;
+    buffer.consumed = 0;
     command_term->set_read_cb(nullptr);
     return res;
 }
@@ -69,39 +68,74 @@ command_result DTE::command(const std::string &cmd, got_line_cb got_line, uint32
     return command(cmd, got_line, time_ms, '\n');
 }
 
-bool DTE::setup_cmux()
+bool DTE::exit_cmux()
 {
-    auto original_term = std::move(term);
-    if (original_term == nullptr) {
+    if (!cmux_term->deinit()) {
         return false;
     }
-    auto cmux_term = std::make_shared<CMux>(std::move(original_term), std::move(buffer), buffer_size);
+    auto ejected = cmux_term->detach();
+    // return the ejected terminal and buffer back to this DTE
+    command_term = std::move(ejected.first);
+    buffer = std::move(ejected.second);
+    data_term = command_term;
+    return true;
+}
+
+bool DTE::setup_cmux()
+{
+    cmux_term = std::make_shared<CMux>(command_term, std::move(buffer));
     if (cmux_term == nullptr) {
         return false;
     }
-    buffer_size = 0;
     if (!cmux_term->init()) {
         return false;
     }
-    term = std::make_unique<CMuxInstance>(cmux_term, 0);
-    if (term == nullptr) {
+    command_term = std::make_unique<CMuxInstance>(cmux_term, 0);
+    if (command_term == nullptr) {
         return false;
     }
-    command_term = term.get(); // use command terminal as previously
-    other_term = std::make_unique<CMuxInstance>(cmux_term, 1);
+    data_term = std::make_unique<CMuxInstance>(cmux_term, 1);
     return true;
 }
 
 bool DTE::set_mode(modem_mode m)
 {
-    mode = m;
-    if (m == modem_mode::DATA_MODE) {
-        term->set_read_cb(on_data);
-        if (other_term) { // if we have the other terminal, let's use it for commands
-            command_term = other_term.get();
+    // transitions (COMMAND|UNDEF) -> CMUX
+    if (m == modem_mode::CMUX_MODE) {
+        if (mode == modem_mode::UNDEF || mode == modem_mode::COMMAND_MODE) {
+            if (setup_cmux()) {
+                mode = m;
+                return true;
+            }
+            mode = modem_mode::UNDEF;
+            return false;
+        }
+    }
+    // transitions (COMMAND|CMUX|UNDEF) -> DATA
+    if (m == modem_mode::DATA_MODE) {
+        if (mode == modem_mode::CMUX_MODE) {
+            // mode stays the same, but need to swap terminals (as command has been switch)
+            data_term.swap(command_term);
+        } else {
+            mode = m;
+        }
+        // prepare the data terminal's callback to the configured std::function (used by netif)
+        data_term->set_read_cb(on_data);
+        return true;
+    }
+    // transitions (DATA|CMUX|UNDEF) -> COMMAND
+    if (m == modem_mode::COMMAND_MODE) {
+        if (mode == modem_mode::CMUX_MODE) {
+            if (exit_cmux()) {
+                mode = m;
+                return true;
+            }
+            mode = modem_mode::UNDEF;
+            return false;
+        } else {
+            mode = m;
+            return true;
         }
-    } else if (m == modem_mode::CMUX_MODE) {
-        return setup_cmux();
     }
     return true;
 }
@@ -109,10 +143,10 @@ bool DTE::set_mode(modem_mode m)
 void DTE::set_read_cb(std::function<bool(uint8_t *, size_t)> f)
 {
     on_data = std::move(f);
-    term->set_read_cb([this](uint8_t *data, size_t len) {
+    data_term->set_read_cb([this](uint8_t *data, size_t len) {
         if (!data) { // if no data available from terminal callback -> need to explicitly read some
             data = buffer.get();
-            len = term->read(buffer.get(), buffer_size);
+            len = data_term->read(buffer.get(), buffer.size);
         }
         if (on_data) {
             return on_data(data, len);
@@ -123,14 +157,20 @@ void DTE::set_read_cb(std::function<bool(uint8_t *, size_t)> f)
 
 int DTE::read(uint8_t **d, size_t len)
 {
-    auto data_to_read = std::min(len, buffer_size);
+    auto data_to_read = std::min(len, buffer.size);
     auto data = buffer.get();
-    auto actual_len = term->read(data, data_to_read);
+    auto actual_len = data_term->read(data, data_to_read);
     *d = data;
     return actual_len;
 }
 
 int DTE::write(uint8_t *data, size_t len)
 {
-    return term->write(data, len);
-}
+    return data_term->write(data, len);
+}
+
+/**
+ * Implemented here to keep all headers C++11 compliant
+ */
+unique_buffer::unique_buffer(size_t size):
+    data(std::make_unique<uint8_t[]>(size)), size(size), consumed(0) {}

components/esp_modem/src/esp_modem_netif_linux.cpp

@@ -54,13 +54,16 @@ void Netif::start()
     signal.set(PPP_STARTED);
 }
 
-void Netif::stop() {}
+void Netif::stop()
+{
+    ppp_dte->set_read_cb(nullptr);
+    signal.clear(PPP_STARTED);
+}
 
 Netif::~Netif() = default;
 
 void Netif::wait_until_ppp_exits()
 {
-
 }
 
 } // namespace esp_modem

components/esp_modem/test/host_test/main/LoopbackTerm.cpp

@@ -15,13 +15,17 @@ void LoopbackTerm::stop()
 
 int LoopbackTerm::write(uint8_t *data, size_t len)
 {
+    if (inject_by) {    // injection test: ignore what we write, but respond with injected data
+        auto ret = std::async(&LoopbackTerm::batch_read, this);
+        return len;
+    }
     if (len > 2 && (data[len - 1] == '\r' || data[len - 1] == '+') ) { // Simple AT responder
         std::string command((char *)data, len);
         std::string response;
         if (command == "+++") {
             response = "NO CARRIER\r\n";
         } else if (command == "ATE1\r" || command == "ATE0\r") {
-            response = "OK\r\n";
+            response = "OK\r\n ";
         } else if (command == "ATO\r") {
             response = "ERROR\r\n";
         } else if (command.find("ATD") != std::string::npos) {
@@ -39,7 +43,16 @@ int LoopbackTerm::write(uint8_t *data, size_t len)
         } else if (command.find("AT+CPIN?\r") != std::string::npos) {
             response = pin_ok ? "+CPIN: READY\r\nOK\r\n" : "+CPIN: SIM PIN\r\nOK\r\n";
         } else if (command.find("AT") != std::string::npos) {
-            response = "OK\r\n";
+            if (command.length() > 4) {
+                response = command;
+                response[0] = 'O';
+                response[1] = 'K';
+                response[2] = '\r';
+                response[3] = '\n';
+            } else {
+                response = "OK\r\n";
+            }
+
         }
         if (!response.empty()) {
             data_len = response.length();
@@ -51,7 +64,7 @@ int LoopbackTerm::write(uint8_t *data, size_t len)
     }
     if (len > 2 && data[0] == 0xf9) { // Simple CMUX responder
         // turn the request into a reply -> implements CMUX loopback
-        if (data[2] == 0x3f) {  // SABM command
+        if (data[2] == 0x3f || data[2] == 0x53) {  // SABM command
             data[2] = 0x73;
         } else if (data[2] == 0xef) { // Generic request
             data[2] = 0xff;         // generic reply
@@ -67,6 +80,8 @@ int LoopbackTerm::write(uint8_t *data, size_t len)
 int LoopbackTerm::read(uint8_t *data, size_t len)
 {
     size_t read_len = std::min(data_len, len);
+    if (inject_by && read_len > inject_by)
+        read_len = inject_by;
     if (read_len) {
         if (loopback_data.capacity() < len) {
             loopback_data.reserve(len);
@@ -78,8 +93,30 @@ int LoopbackTerm::read(uint8_t *data, size_t len)
     return read_len;
 }
 
-LoopbackTerm::LoopbackTerm(bool is_bg96): loopback_data(), data_len(0), pin_ok(false), is_bg96(is_bg96) {}
+LoopbackTerm::LoopbackTerm(bool is_bg96): loopback_data(), data_len(0), pin_ok(false), is_bg96(is_bg96), inject_by(0) {}
 
-LoopbackTerm::LoopbackTerm(): loopback_data(), data_len(0), pin_ok(false), is_bg96(false) {}
+LoopbackTerm::LoopbackTerm(): loopback_data(), data_len(0), pin_ok(false), is_bg96(false), inject_by(0) {}
+
+int LoopbackTerm::inject(uint8_t *data, size_t len, size_t injected_by)
+{
+    if (data == nullptr) {
+        inject_by = 0;
+        return 0;
+    }
+
+    loopback_data.resize(len);
+    memcpy(&loopback_data[0], data, len);
+    data_len = len;
+    inject_by = injected_by;
+    return len;
+}
+
+void LoopbackTerm::batch_read()
+{
+    while (data_len > 0) {
+        on_read(nullptr, std::min(inject_by, data_len));
+        Task::Delay(1);
+    }
+}
 
 LoopbackTerm::~LoopbackTerm() = default;