/* * MDNS Server Networking * */ #include #include "mdns_networking.h" extern mdns_server_t * _mdns_server; /* * MDNS Server Networking * */ /** * @brief the receive callback of the raw udp api. Packets are received here * */ static void _udp_recv(void *arg, struct udp_pcb *upcb, struct pbuf *pb, const ip_addr_t *raddr, uint16_t rport) { uint8_t i; while (pb != NULL) { struct pbuf * this_pb = pb; pb = pb->next; this_pb->next = NULL; mdns_rx_packet_t * packet = (mdns_rx_packet_t *)malloc(sizeof(mdns_rx_packet_t)); if (!packet) { //missed packet - no memory pbuf_free(this_pb); continue; } packet->tcpip_if = TCPIP_ADAPTER_IF_MAX; packet->pb = this_pb; packet->src_port = rport; memcpy(&packet->src, raddr, sizeof(ip_addr_t)); packet->dest.type = packet->src.type; if (packet->src.type == IPADDR_TYPE_V4) { packet->ip_protocol = MDNS_IP_PROTOCOL_V4; struct ip_hdr * iphdr = (struct ip_hdr *)(((uint8_t *)(packet->pb->payload)) - UDP_HLEN - IP_HLEN); packet->dest.u_addr.ip4.addr = iphdr->dest.addr; } else { packet->ip_protocol = MDNS_IP_PROTOCOL_V6; struct ip6_hdr * ip6hdr = (struct ip6_hdr *)(((uint8_t *)(packet->pb->payload)) - UDP_HLEN - IP6_HLEN); memcpy(&packet->dest.u_addr.ip6.addr, (uint8_t *)ip6hdr->dest.addr, 16); } packet->multicast = ip_addr_ismulticast(&(packet->dest)); //lwip does not return the proper pcb if you have more than one for the same multicast address (but different interfaces) struct netif * netif = NULL; void * nif = NULL; struct udp_pcb * pcb = NULL; for (i=0; iinterfaces[i].pcbs[packet->ip_protocol].pcb; tcpip_adapter_get_netif (i, &nif); netif = (struct netif *)nif; if (pcb && netif && netif == ip_current_input_netif ()) { if (packet->src.type == IPADDR_TYPE_V4) { if ((packet->src.u_addr.ip4.addr & netif->netmask.u_addr.ip4.addr) != (netif->ip_addr.u_addr.ip4.addr & netif->netmask.u_addr.ip4.addr)) { //packet source is not in the same subnet pcb = NULL; break; } } packet->tcpip_if = i; break; } pcb = NULL; } if (!pcb || !_mdns_server || !_mdns_server->action_queue || _mdns_send_rx_action(packet) != ESP_OK) { pbuf_free(this_pb); free(packet); } } } /** * @brief Stop PCB Main code */ static void _udp_pcb_deinit(tcpip_adapter_if_t tcpip_if, mdns_ip_protocol_t ip_protocol) { if (!_mdns_server) { return; } mdns_pcb_t * _pcb = &_mdns_server->interfaces[tcpip_if].pcbs[ip_protocol]; if (_pcb->pcb) { _pcb->state = PCB_OFF; udp_recv(_pcb->pcb, NULL, NULL); udp_disconnect(_pcb->pcb); udp_remove(_pcb->pcb); free(_pcb->probe_services); _pcb->pcb = NULL; _pcb->probe_ip = false; _pcb->probe_services = NULL; _pcb->probe_services_len = 0; _pcb->probe_running = false; _pcb->failed_probes = 0; } } /** * @brief Start PCB V4 */ static esp_err_t _udp_pcb_v4_init(tcpip_adapter_if_t tcpip_if) { tcpip_adapter_ip_info_t if_ip_info; if (!_mdns_server || _mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V4].pcb) { return ESP_ERR_INVALID_STATE; } if (tcpip_adapter_get_ip_info(tcpip_if, &if_ip_info) || if_ip_info.ip.addr == 0) { return ESP_ERR_INVALID_ARG; } ip_addr_t interface_addr = IPADDR4_INIT(if_ip_info.ip.addr); ip_addr_t multicast_addr; IP_ADDR4(&multicast_addr, 224, 0, 0, 251); if (igmp_joingroup((const struct ip4_addr *)&interface_addr.u_addr.ip4, (const struct ip4_addr *)&multicast_addr.u_addr.ip4)) { return ESP_ERR_INVALID_STATE; } struct udp_pcb * pcb = udp_new_ip_type(IPADDR_TYPE_V4); if (!pcb) { return ESP_ERR_NO_MEM; } if (udp_bind(pcb, &interface_addr, MDNS_SERVICE_PORT) != 0) { udp_remove(pcb); return ESP_ERR_INVALID_STATE; } pcb->mcast_ttl = 1; pcb->remote_port = MDNS_SERVICE_PORT; ip_addr_copy(pcb->multicast_ip, interface_addr); ip_addr_copy(pcb->remote_ip, multicast_addr); _mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V4].pcb = pcb; _mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V4].failed_probes = 0; udp_recv(pcb, &_udp_recv, _mdns_server); return ESP_OK; } /** * @brief Start PCB V6 */ static esp_err_t _udp_pcb_v6_init(tcpip_adapter_if_t tcpip_if) { ip_addr_t multicast_addr = IPADDR6_INIT(0x000002ff, 0, 0, 0xfb000000); ip_addr_t interface_addr; interface_addr.type = IPADDR_TYPE_V6; if (!_mdns_server || _mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V6].pcb) { return ESP_ERR_INVALID_STATE; } if (tcpip_adapter_get_ip6_linklocal(tcpip_if, &interface_addr.u_addr.ip6)) { return ESP_ERR_INVALID_ARG; } if (mld6_joingroup(&(interface_addr.u_addr.ip6), &(multicast_addr.u_addr.ip6))) { return ESP_ERR_INVALID_STATE; } struct udp_pcb * pcb = udp_new_ip_type(IPADDR_TYPE_V6); if (!pcb) { return ESP_ERR_NO_MEM; } if (udp_bind(pcb, &interface_addr, MDNS_SERVICE_PORT) != 0) { udp_remove(pcb); return ESP_ERR_INVALID_STATE; } pcb->remote_port = MDNS_SERVICE_PORT; ip_addr_copy(pcb->remote_ip, multicast_addr); _mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V6].pcb = pcb; _mdns_server->interfaces[tcpip_if].pcbs[MDNS_IP_PROTOCOL_V6].failed_probes = 0; udp_recv(pcb, &_udp_recv, _mdns_server); return ESP_OK; } /** * @brief Start PCB Main code */ static esp_err_t _udp_pcb_init(tcpip_adapter_if_t tcpip_if, mdns_ip_protocol_t ip_protocol) { if (ip_protocol == MDNS_IP_PROTOCOL_V4) { return _udp_pcb_v4_init(tcpip_if); } else if (ip_protocol == MDNS_IP_PROTOCOL_V6) { return _udp_pcb_v6_init(tcpip_if); } return ESP_ERR_INVALID_ARG; } typedef struct { struct tcpip_api_call call; tcpip_adapter_if_t tcpip_if; mdns_ip_protocol_t ip_protocol; esp_err_t err; } mdns_api_call_t; /** * @brief Start PCB from LwIP thread */ static err_t _mdns_pcb_init_api(struct tcpip_api_call *api_call_msg) { mdns_api_call_t * msg = (mdns_api_call_t *)api_call_msg; msg->err = _udp_pcb_init(msg->tcpip_if, msg->ip_protocol); return msg->err; } /** * @brief Stop PCB from LwIP thread */ static err_t _mdns_pcb_deinit_api(struct tcpip_api_call *api_call_msg) { mdns_api_call_t * msg = (mdns_api_call_t *)api_call_msg; _udp_pcb_deinit(msg->tcpip_if, msg->ip_protocol); msg->err = ESP_OK; return ESP_OK; } /* * Non-static functions below are * - _mdns prefixed * - commented in mdns_networking.h header */ esp_err_t _mdns_pcb_init(tcpip_adapter_if_t tcpip_if, mdns_ip_protocol_t ip_protocol) { mdns_api_call_t msg = { .tcpip_if = tcpip_if, .ip_protocol = ip_protocol }; tcpip_api_call(_mdns_pcb_init_api, (struct tcpip_api_call*)&msg); return msg.err; } esp_err_t _mdns_pcb_deinit(tcpip_adapter_if_t tcpip_if, mdns_ip_protocol_t ip_protocol) { mdns_api_call_t msg = { .tcpip_if = tcpip_if, .ip_protocol = ip_protocol }; tcpip_api_call(_mdns_pcb_deinit_api, (struct tcpip_api_call*)&msg); return msg.err; } size_t _mdns_udp_pcb_write(tcpip_adapter_if_t tcpip_if, mdns_ip_protocol_t ip_protocol, const ip_addr_t *ip, uint16_t port, uint8_t * data, size_t len) { struct netif * netif = NULL; void * nif = NULL; esp_err_t err = tcpip_adapter_get_netif(tcpip_if, &nif); netif = (struct netif *)nif; if (err) { return 0; } struct pbuf* pbt = pbuf_alloc(PBUF_TRANSPORT, len, PBUF_RAM); if (pbt == NULL) { return 0; } memcpy((uint8_t *)pbt->payload, data, len); err = udp_sendto_if (_mdns_server->interfaces[tcpip_if].pcbs[ip_protocol].pcb, pbt, ip, port, netif); pbuf_free(pbt); if (err) { return 0; } return len; }