mirror of
				https://github.com/espressif/esp-idf.git
				synced 2025-11-04 09:01:40 +01:00 
			
		
		
		
	linux/lwip: Wrap some IO posix functions * to workaourd the FreeRTOS EINTR issue (when building without lwip) * to correctly choose the sub-system based on fd (when building with lwip) -- passing control to either linux/system or to lwip This commit also addapts tapio-if to provide DHCP client by default and configurable settings for static IP
		
			
				
	
	
		
			135 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			135 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
 | 
						|
 *
 | 
						|
 * SPDX-License-Identifier: Apache-2.0
 | 
						|
 */
 | 
						|
#include <stdlib.h>
 | 
						|
#include <unistd.h>
 | 
						|
#include <string.h>
 | 
						|
#include "esp_err.h"
 | 
						|
#include "esp_log.h"
 | 
						|
#include "esp_netif.h"
 | 
						|
 | 
						|
// Use linux system sockets to connect to tap interface
 | 
						|
#define LWIP_HDR_LINUX_SYS_SOCKETS_H
 | 
						|
#include <sys/socket.h>
 | 
						|
#include <fcntl.h>
 | 
						|
 | 
						|
#include <sys/ioctl.h>
 | 
						|
#include <sys/types.h>
 | 
						|
#include <sys/ioctl.h>
 | 
						|
#include <lwip/sys.h>
 | 
						|
#include "errno.h"
 | 
						|
 | 
						|
#include <linux/if.h>
 | 
						|
#include <linux/if_tun.h>
 | 
						|
 | 
						|
#define DEVTAP "/dev/net/tun"
 | 
						|
#define DEVTAP_NAME "tap0"
 | 
						|
 | 
						|
 | 
						|
typedef struct tap_io {
 | 
						|
    esp_netif_driver_base_t base;
 | 
						|
    int fd;
 | 
						|
} tap_io_t;
 | 
						|
 | 
						|
static const char *TAG = "tap-netif";
 | 
						|
 | 
						|
static void tapio_input_task(void *arg)
 | 
						|
{
 | 
						|
    tap_io_t *io = arg;
 | 
						|
    fd_set fdset;
 | 
						|
    int ret;
 | 
						|
    while (1) {
 | 
						|
        FD_ZERO(&fdset);
 | 
						|
        FD_SET(io->fd, &fdset);
 | 
						|
 | 
						|
        /* Wait for a packet to arrive. */
 | 
						|
        ret = select(io->fd + 1, &fdset, NULL, NULL, NULL);
 | 
						|
 | 
						|
        if (ret == 1) {
 | 
						|
            /* Handle incoming packet. */
 | 
						|
            ssize_t readlen;
 | 
						|
            char buf[1518]; /* max packet size including VLAN excluding CRC */
 | 
						|
 | 
						|
            /* Obtain the size of the packet and put it into the "len"
 | 
						|
               variable. */
 | 
						|
            readlen = read(io->fd, buf, sizeof(buf));
 | 
						|
            if (readlen < 0) {
 | 
						|
                ESP_LOGE(TAG, "Failed to read from tap fd: returned %ld", readlen);
 | 
						|
                exit(1);
 | 
						|
            }
 | 
						|
#if CONFIG_EXAMPLE_CONNECT_TAPIF_IN_LOSS
 | 
						|
            if (((double)rand()/(double)RAND_MAX) < ((double)CONFIG_EXAMPLE_CONNECT_TAPIF_IN_LOSS)/100.0) {
 | 
						|
                ESP_LOGW(TAG, "Simulated packet drop on input");
 | 
						|
                continue;
 | 
						|
            }
 | 
						|
#endif
 | 
						|
            esp_netif_receive(io->base.netif, buf, readlen, NULL);
 | 
						|
        } else if (ret == -1) {
 | 
						|
            if (errno == EINTR /* Interrupted system call (used by FreeRTOS simulated interrupts) */) {
 | 
						|
                vTaskDelay(1); // yield to the FreeRTOS simulator
 | 
						|
            } else {
 | 
						|
                ESP_LOGE(TAG, "tapif_thread: select() error(%d), %s", errno, strerror(errno));
 | 
						|
            }
 | 
						|
        }
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static esp_err_t tapio_start(esp_netif_t *esp_netif, void *arg)
 | 
						|
{
 | 
						|
    tap_io_t *io = arg;
 | 
						|
    io->base.netif = esp_netif;
 | 
						|
    esp_netif_action_start(esp_netif, 0, 0, 0);
 | 
						|
 | 
						|
    sys_thread_new("tapio_rx", tapio_input_task, io, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
 | 
						|
 | 
						|
    return ESP_OK;
 | 
						|
}
 | 
						|
 | 
						|
void *tapio_create(void)
 | 
						|
{
 | 
						|
    static tap_io_t tap_io = {};
 | 
						|
    tap_io.base.post_attach = tapio_start;
 | 
						|
    tap_io.fd = open(DEVTAP, O_RDWR);
 | 
						|
    if (tap_io.fd == -1) {
 | 
						|
        ESP_LOGE(TAG, "Cannot open tap device %s", DEVTAP);
 | 
						|
        return NULL;
 | 
						|
    }
 | 
						|
 | 
						|
    struct ifreq ifr = {};
 | 
						|
    memset(&ifr, 0, sizeof(ifr));
 | 
						|
 | 
						|
    strncpy(ifr.ifr_name, DEVTAP_NAME, sizeof(ifr.ifr_name));
 | 
						|
    ifr.ifr_name[sizeof(ifr.ifr_name)-1] = 0; /* ensure \0 termination */
 | 
						|
    ifr.ifr_flags = IFF_TAP|IFF_NO_PI;
 | 
						|
    if (ioctl(tap_io.fd, TUNSETIFF, (void *) &ifr) < 0) {
 | 
						|
        ESP_LOGE(TAG, "Cannot configure ioctl(TUNSETIFF) for \"%s\"", DEVTAP);
 | 
						|
        return NULL;
 | 
						|
    }
 | 
						|
 | 
						|
 | 
						|
    return &tap_io;
 | 
						|
}
 | 
						|
 | 
						|
esp_err_t tapio_output(void *h, void *buffer, size_t len)
 | 
						|
{
 | 
						|
    tap_io_t *io = h;
 | 
						|
    ssize_t written;
 | 
						|
 | 
						|
#if CONFIG_EXAMPLE_CONNECT_TAPIF_OUT_LOSS
 | 
						|
    if (((double)rand()/(double)RAND_MAX) < ((double)CONFIG_EXAMPLE_CONNECT_TAPIF_OUT_LOSS)/100.0) {
 | 
						|
        ESP_LOGW(TAG, "Simulated packet drop on output");
 | 
						|
        return ESP_OK; /* ESP_OK because we simulate packet loss on cable */
 | 
						|
    }
 | 
						|
#endif
 | 
						|
 | 
						|
    /* signal that packet should be sent(); */
 | 
						|
    written = write(io->fd, buffer, len);
 | 
						|
    if (written < len) {
 | 
						|
        ESP_LOGE(TAG, "Failed to write from tap fd: returned %ld", written);
 | 
						|
        return ESP_FAIL;
 | 
						|
    }
 | 
						|
    return ESP_OK;
 | 
						|
}
 |