esp-idf/components/mdns/mdns_networking_socket.c
David Cermak 42ba8a8338 mdns: Fix copyright messages, update API descrition
* Impove docs and comments on custom netifs
* Make predef interfaces const, minor docs fixes
2022-03-09 07:33:23 +01:00

496 lines
18 KiB
C

/*
* SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @brief MDNS Server Networking module implemented using BSD sockets
*/
#include <string.h>
#include "esp_event.h"
#include "mdns_networking.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <errno.h>
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/param.h>
#include "esp_log.h"
#if defined(CONFIG_IDF_TARGET_LINUX)
#include <sys/ioctl.h>
#include <net/if.h>
#endif
extern mdns_server_t * _mdns_server;
static const char *TAG = "MDNS_Networking";
static bool s_run_sock_recv_task = false;
static int create_socket(esp_netif_t *netif);
static int join_mdns_multicast_group(int sock, esp_netif_t *netif, mdns_ip_protocol_t ip_protocol);
#if defined(CONFIG_IDF_TARGET_LINUX)
// Need to define packet buffer struct on linux
struct pbuf {
struct pbuf * next;
void * payload;
size_t tot_len;
size_t len;
};
#else
// Compatibility define to access sock-addr struct the same way for lwip and linux
#define s6_addr32 un.u32_addr
#endif // CONFIG_IDF_TARGET_LINUX
static void delete_socket(int sock)
{
close(sock);
}
static struct udp_pcb* sock_to_pcb(int sock)
{
if (sock < 0) {
return NULL;
}
// Note: sock=0 is a valid descriptor, so save it as +1 ("1" is a valid pointer)
intptr_t sock_plus_one = sock + 1;
return (struct udp_pcb*)sock_plus_one;
}
static int pcb_to_sock(struct udp_pcb* pcb)
{
if (pcb == NULL) {
return -1;
}
intptr_t sock_plus_one = (intptr_t)pcb;
return sock_plus_one - 1;
}
void* _mdns_get_packet_data(mdns_rx_packet_t *packet)
{
return packet->pb->payload;
}
size_t _mdns_get_packet_len(mdns_rx_packet_t *packet)
{
return packet->pb->len;
}
void _mdns_packet_free(mdns_rx_packet_t *packet)
{
free(packet->pb->payload);
free(packet->pb);
free(packet);
}
esp_err_t _mdns_pcb_deinit(mdns_if_t tcpip_if, mdns_ip_protocol_t ip_protocol)
{
struct udp_pcb * pcb = _mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].pcb;
_mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].pcb = NULL;
if (_mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V4].pcb == NULL &&
_mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V6].pcb == NULL) {
// if the interface for both protocol uninitialized, close the interface socket
int sock = pcb_to_sock(pcb);
if (sock >= 0) {
delete_socket(sock);
}
}
for (int i=0; i<MDNS_MAX_INTERFACES; i++) {
for (int j=0; j<MDNS_IP_PROTOCOL_MAX; j++) {
if (_mdns_server->interfaces[i].pcbs[j].pcb)
// If any of the interfaces/protocol initialized
return ESP_OK;
}
}
// no interface alive, stop the rx task
s_run_sock_recv_task = false;
vTaskDelay(pdMS_TO_TICKS(500));
return ESP_OK;
}
#if defined(CONFIG_IDF_TARGET_LINUX)
#ifdef CONFIG_LWIP_IPV6
static char* inet6_ntoa_r(struct in6_addr addr, char* ptr, size_t size)
{
inet_ntop(AF_INET6, &(addr.s6_addr32[0]), ptr, size);
return ptr;
}
#endif // CONFIG_LWIP_IPV6
static char* inet_ntoa_r(struct in_addr addr, char* ptr, size_t size)
{
char * res = inet_ntoa(addr);
if (res && strlen(res) < size) {
strcpy(ptr, res);
}
return res;
}
#endif // CONFIG_IDF_TARGET_LINUX
static inline char* get_string_address(struct sockaddr_storage *source_addr)
{
static char address_str[40]; // 40=(8*4+7+term) is the max size of ascii IPv6 addr "XXXX:XX...XX:XXXX"
char *res = NULL;
// Convert ip address to string
if (source_addr->ss_family == PF_INET) {
res = inet_ntoa_r(((struct sockaddr_in *)source_addr)->sin_addr, address_str, sizeof(address_str));
}
#ifdef CONFIG_LWIP_IPV6
else if (source_addr->ss_family == PF_INET6) {
res = inet6_ntoa_r(((struct sockaddr_in6 *)source_addr)->sin6_addr, address_str, sizeof(address_str));
}
#endif
if (!res) {
address_str[0] = '\0'; // Returns empty string if conversion didn't succeed
}
return address_str;
}
static inline size_t espaddr_to_inet(const esp_ip_addr_t *addr, const uint16_t port, const mdns_ip_protocol_t ip_protocol, struct sockaddr_storage *in_addr)
{
size_t ss_addr_len = 0;
memset(in_addr, 0, sizeof(struct sockaddr_storage));
if (ip_protocol == MDNS_IP_PROTOCOL_V4 && addr->type == ESP_IPADDR_TYPE_V4) {
in_addr->ss_family = PF_INET;
#if !defined(CONFIG_IDF_TARGET_LINUX)
in_addr->s2_len = sizeof(struct sockaddr_in);
#endif
ss_addr_len = sizeof(struct sockaddr_in);
struct sockaddr_in *in_addr_ip4 = (struct sockaddr_in *) in_addr;
in_addr_ip4->sin_port = port;
in_addr_ip4->sin_addr.s_addr = addr->u_addr.ip4.addr;
}
#if CONFIG_LWIP_IPV6
else if (ip_protocol == MDNS_IP_PROTOCOL_V6 && addr->type == ESP_IPADDR_TYPE_V6) {
memset(in_addr, 0, sizeof(struct sockaddr_storage));
in_addr->ss_family = PF_INET6;
#if !defined(CONFIG_IDF_TARGET_LINUX)
in_addr->s2_len = sizeof(struct sockaddr_in6);
#endif
ss_addr_len = sizeof(struct sockaddr_in6);
struct sockaddr_in6 * in_addr_ip6 = (struct sockaddr_in6 *)in_addr;
uint32_t *u32_addr = in_addr_ip6->sin6_addr.s6_addr32;
in_addr_ip6->sin6_port = port;
u32_addr[0] = addr->u_addr.ip6.addr[0];
u32_addr[1] = addr->u_addr.ip6.addr[1];
u32_addr[2] = addr->u_addr.ip6.addr[2];
u32_addr[3] = addr->u_addr.ip6.addr[3];
}
#endif // CONFIG_LWIP_IPV6
return ss_addr_len;
}
size_t _mdns_udp_pcb_write(mdns_if_t tcpip_if, mdns_ip_protocol_t ip_protocol, const esp_ip_addr_t *ip, uint16_t port, uint8_t * data, size_t len)
{
int sock = pcb_to_sock(_mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].pcb);
if (sock < 0) {
return 0;
}
struct sockaddr_storage in_addr;
size_t ss_size = espaddr_to_inet(ip, htons(port), ip_protocol, &in_addr);
if (!ss_size) {
ESP_LOGE(TAG, "espaddr_to_inet() failed: Mismatch of IP protocols");
return 0;
}
ESP_LOGD(TAG, "[sock=%d]: Sending to IP %s port %d", sock, get_string_address(&in_addr), port);
ssize_t actual_len = sendto(sock, data, len, 0, (struct sockaddr *)&in_addr, ss_size);
if (actual_len < 0) {
ESP_LOGE(TAG, "[sock=%d]: _mdns_udp_pcb_write sendto() has failed\n errno=%d: %s", sock, errno, strerror(errno));
}
return actual_len;
}
static inline void inet_to_espaddr(const struct sockaddr_storage *in_addr, esp_ip_addr_t *addr, uint16_t *port)
{
if (in_addr->ss_family == PF_INET) {
struct sockaddr_in * in_addr_ip4 = (struct sockaddr_in *)in_addr;
memset(addr, 0, sizeof(esp_ip_addr_t));
*port = in_addr_ip4->sin_port;
addr->u_addr.ip4.addr = in_addr_ip4->sin_addr.s_addr;
addr->type = ESP_IPADDR_TYPE_V4;
}
#if CONFIG_LWIP_IPV6
else if (in_addr->ss_family == PF_INET6) {
struct sockaddr_in6 * in_addr_ip6 = (struct sockaddr_in6 *)in_addr;
memset(addr, 0, sizeof(esp_ip_addr_t));
*port = in_addr_ip6->sin6_port;
uint32_t *u32_addr = in_addr_ip6->sin6_addr.s6_addr32;
if (u32_addr[0] == 0 && u32_addr[1] == 0 && u32_addr[2] == esp_netif_htonl(0x0000FFFFUL)) {
// Mapped IPv4 address, convert directly to IPv4
addr->type = ESP_IPADDR_TYPE_V4;
addr->u_addr.ip4.addr = u32_addr[3];
} else {
addr->type = ESP_IPADDR_TYPE_V6;
addr->u_addr.ip6.addr[0] = u32_addr[0];
addr->u_addr.ip6.addr[1] = u32_addr[1];
addr->u_addr.ip6.addr[2] = u32_addr[2];
addr->u_addr.ip6.addr[3] = u32_addr[3];
}
}
#endif // CONFIG_LWIP_IPV6
}
void sock_recv_task(void* arg)
{
while (s_run_sock_recv_task) {
struct timeval tv = {
.tv_sec = 1,
.tv_usec = 0,
};
fd_set rfds;
FD_ZERO(&rfds);
int max_sock = -1;
for (int i=0; i<MDNS_MAX_INTERFACES; i++) {
for (int j=0; j<MDNS_IP_PROTOCOL_MAX; j++) {
int sock = pcb_to_sock(_mdns_server->interfaces[i].pcbs[j].pcb);
if (sock >= 0) {
FD_SET(sock, &rfds);
max_sock = MAX(max_sock, sock);
}
}
}
if (max_sock < 0) {
vTaskDelay(pdMS_TO_TICKS(1000));
ESP_LOGI(TAG, "No sock!");
continue;
}
int s = select(max_sock + 1, &rfds, NULL, NULL, &tv);
if (s < 0) {
ESP_LOGE(TAG, "Select failed. errno=%d: %s", errno, strerror(errno));
break;
} else if (s > 0) {
for (int tcpip_if=0; tcpip_if<MDNS_MAX_INTERFACES; tcpip_if++) {
// Both protocols share once socket
int sock = pcb_to_sock(_mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V4].pcb);
if (sock < 0) {
sock = pcb_to_sock(_mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V6].pcb);
}
if (sock < 0) {
continue;
}
if (FD_ISSET(sock, &rfds)) {
static char recvbuf[MDNS_MAX_PACKET_SIZE];
uint16_t port = 0;
struct sockaddr_storage raddr; // Large enough for both IPv4 or IPv6
socklen_t socklen = sizeof(struct sockaddr_storage);
esp_ip_addr_t addr = {0};
int len = recvfrom(sock, recvbuf, sizeof(recvbuf), 0,
(struct sockaddr *) &raddr, &socklen);
if (len < 0) {
ESP_LOGE(TAG, "multicast recvfrom failed. errno=%d: %s", errno, strerror(errno));
break;
}
ESP_LOGD(TAG, "[sock=%d]: Received from IP:%s", sock, get_string_address(&raddr));
ESP_LOG_BUFFER_HEXDUMP(TAG, recvbuf, len, ESP_LOG_VERBOSE);
inet_to_espaddr(&raddr, &addr, &port);
// Allocate the packet structure and pass it to the mdns main engine
mdns_rx_packet_t *packet = (mdns_rx_packet_t *) calloc(1, sizeof(mdns_rx_packet_t));
struct pbuf *packet_pbuf = calloc(1, sizeof(struct pbuf));
uint8_t *buf = malloc(len);
if (packet == NULL || packet_pbuf == NULL || buf == NULL ) {
free(buf);
free(packet_pbuf);
free(packet);
HOOK_MALLOC_FAILED;
ESP_LOGE(TAG, "Failed to allocate the mdns packet");
continue;
}
memcpy(buf, recvbuf, len);
packet_pbuf->next = NULL;
packet_pbuf->payload = buf;
packet_pbuf->tot_len = len;
packet_pbuf->len = len;
packet->tcpip_if = tcpip_if;
packet->pb = packet_pbuf;
packet->src_port = ntohs(port);
memcpy(&packet->src, &addr, sizeof(esp_ip_addr_t));
// TODO(IDF-3651): Add the correct dest addr -- for mdns to decide multicast/unicast
// Currently it's enough to assume the packet is multicast and mdns to check the source port of the packet
memset(&packet->dest, 0, sizeof(esp_ip_addr_t));
packet->multicast = 1;
packet->dest.type = packet->src.type;
packet->ip_protocol =
packet->src.type == ESP_IPADDR_TYPE_V4 ? MDNS_IP_PROTOCOL_V4 : MDNS_IP_PROTOCOL_V6;
if (!_mdns_server || !_mdns_server->action_queue || _mdns_send_rx_action(packet) != ESP_OK) {
ESP_LOGE(TAG, "_mdns_send_rx_action failed!");
free(packet->pb->payload);
free(packet->pb);
free(packet);
}
}
}
}
}
vTaskDelete(NULL);
}
static void mdns_networking_init(void)
{
if (s_run_sock_recv_task == false) {
s_run_sock_recv_task = true;
xTaskCreate( sock_recv_task, "mdns recv task", 3*1024, NULL, 5, NULL );
}
}
static struct udp_pcb* create_pcb(mdns_if_t tcpip_if, mdns_ip_protocol_t ip_protocol)
{
if (_mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].pcb) {
return _mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].pcb;
}
mdns_ip_protocol_t other_ip_proto = ip_protocol==MDNS_IP_PROTOCOL_V4?MDNS_IP_PROTOCOL_V6:MDNS_IP_PROTOCOL_V4;
esp_netif_t *netif = _mdns_get_esp_netif(tcpip_if);
if (_mdns_server->interfaces[tcpip_if].pcbs[other_ip_proto].pcb) {
struct udp_pcb* other_pcb = _mdns_server->interfaces[tcpip_if].pcbs[other_ip_proto].pcb;
int err = join_mdns_multicast_group(pcb_to_sock(other_pcb), netif, ip_protocol);
if (err < 0) {
ESP_LOGE(TAG, "Failed to add ipv6 multicast group for protocol %d", ip_protocol);
return NULL;
}
return other_pcb;
}
int sock = create_socket(netif);
if (sock < 0) {
ESP_LOGE(TAG, "Failed to create the socket!");
return NULL;
}
int err = join_mdns_multicast_group(sock, netif, ip_protocol);
if (err < 0) {
ESP_LOGE(TAG, "Failed to add ipv6 multicast group for protocol %d", ip_protocol);
}
return sock_to_pcb(sock);
}
esp_err_t _mdns_pcb_init(mdns_if_t tcpip_if, mdns_ip_protocol_t ip_protocol)
{
ESP_LOGI(TAG, "_mdns_pcb_init(tcpip_if=%d, ip_protocol=%d)", tcpip_if, ip_protocol);
_mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].pcb = create_pcb(tcpip_if, ip_protocol);
_mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].failed_probes = 0;
mdns_networking_init();
return ESP_OK;
}
static int create_socket(esp_netif_t *netif)
{
#if CONFIG_LWIP_IPV6
int sock = socket(PF_INET6, SOCK_DGRAM, 0);
#else
int sock = socket(PF_INET, SOCK_DGRAM, 0);
#endif
if (sock < 0) {
ESP_LOGE(TAG, "Failed to create socket. errno=%d: %s", errno, strerror(errno));
return -1;
}
int on = 1;
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on) ) < 0) {
ESP_LOGE(TAG, "Failed setsockopt() to set SO_REUSEADDR. errno=%d: %s\n", errno, strerror(errno));
}
// Bind the socket to any address
#if CONFIG_LWIP_IPV6
struct sockaddr_in6 saddr = { INADDR_ANY };
saddr.sin6_family = AF_INET6;
saddr.sin6_port = htons(5353);
bzero(&saddr.sin6_addr.s6_addr, sizeof(saddr.sin6_addr.s6_addr));
int err = bind(sock, (struct sockaddr *)&saddr, sizeof(struct sockaddr_in6));
if (err < 0) {
ESP_LOGE(TAG, "Failed to bind socket. errno=%d: %s", errno, strerror(errno));
goto err;
}
#else
struct sockaddr_in saddr = { 0 };
saddr.sin_family = AF_INET;
saddr.sin_port = htons(5353);
bzero(&saddr.sin_addr.s_addr, sizeof(saddr.sin_addr.s_addr));
int err = bind(sock, (struct sockaddr *)&saddr, sizeof(struct sockaddr_in));
if (err < 0) {
ESP_LOGE(TAG, "Failed to bind socket. errno=%d: %s", errno, strerror(errno));
goto err;
}
#endif // CONFIG_LWIP_IPV6
struct ifreq ifr;
esp_netif_get_netif_impl_name(netif, ifr.ifr_name);
int ret = setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, (void*)&ifr, sizeof(struct ifreq));
if (ret < 0) {
ESP_LOGE(TAG, "\"%s\" Unable to bind socket to specified interface. errno=%d: %s", esp_netif_get_desc(netif), errno, strerror(errno));
goto err;
}
return sock;
err:
close(sock);
return -1;
}
#if CONFIG_LWIP_IPV6
static int socket_add_ipv6_multicast_group(int sock, esp_netif_t *netif)
{
int ifindex = esp_netif_get_netif_impl_index(netif);
int err = setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_IF, &ifindex, sizeof(ifindex));
if (err < 0) {
ESP_LOGE(TAG, "Failed to set IPV6_MULTICAST_IF. errno=%d: %s", errno, strerror(errno));
return err;
}
struct ipv6_mreq v6imreq = { 0 };
esp_ip_addr_t multi_addr = ESP_IP6ADDR_INIT(0x000002ff, 0, 0, 0xfb000000);
memcpy(&v6imreq.ipv6mr_multiaddr, &multi_addr.u_addr.ip6.addr, sizeof(v6imreq.ipv6mr_multiaddr));
v6imreq.ipv6mr_interface = ifindex;
err = setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &v6imreq, sizeof(struct ipv6_mreq));
if (err < 0) {
ESP_LOGE(TAG, "Failed to set IPV6_ADD_MEMBERSHIP. errno=%d: %s", errno, strerror(errno));
return err;
}
return err;
}
#endif // CONFIG_LWIP_IPV6
static int socket_add_ipv4_multicast_group(int sock, esp_netif_t *netif)
{
struct ip_mreq imreq = { 0 };
int err = 0;
esp_netif_ip_info_t ip_info = { 0 };
if (esp_netif_get_ip_info(netif, &ip_info) != ESP_OK) {
ESP_LOGE(TAG, "Failed to esp_netif_get_ip_info()");
goto err;
}
imreq.imr_interface.s_addr = ip_info.ip.addr;
esp_ip_addr_t multicast_addr = ESP_IP4ADDR_INIT(224, 0, 0, 251);
imreq.imr_multiaddr.s_addr = multicast_addr.u_addr.ip4.addr;
err = setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, &imreq, sizeof(struct ip_mreq));
if (err < 0) {
ESP_LOGE(TAG, "[sock=%d] Failed to set IP_ADD_MEMBERSHIP. errno=%d: %s", sock, errno, strerror(errno));
goto err;
}
err:
return err;
}
static int join_mdns_multicast_group(int sock, esp_netif_t *netif, mdns_ip_protocol_t ip_protocol)
{
if (ip_protocol == MDNS_IP_PROTOCOL_V4) {
return socket_add_ipv4_multicast_group(sock, netif);
}
#if CONFIG_LWIP_IPV6
if (ip_protocol == MDNS_IP_PROTOCOL_V6) {
return socket_add_ipv6_multicast_group(sock, netif);
}
#endif // CONFIG_LWIP_IPV6
return -1;
}