X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fdiscovery.c;h=e144c286cbafcefac637b2bbeff50b5e3fa06be7;hb=HEAD;hp=b50aea8d80f689991355db5dac9269eb292fa06e;hpb=5ae4edd8e422fb1b184fb5cbd6c48de0c048c7b8;p=meshlink diff --git a/src/discovery.c b/src/discovery.c index b50aea8d..032b5599 100644 --- a/src/discovery.c +++ b/src/discovery.c @@ -1,594 +1,1063 @@ - +/* + discovery.c -- local network discovery + Copyright (C) 2014-2021 Guus Sliepen + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#define __APPLE_USE_RFC_3542 +#include "system.h" + +#if defined(__APPLE__) +#include +#include +#include +#include +#include +#include +#elif defined(__unix) && !defined(__linux) +#include +#include +#include +#elif defined(__linux) +#include +#include +#include +#include +#include +#endif + +#include "mdns.h" #include "meshlink_internal.h" +#include "event.h" #include "discovery.h" #include "sockaddr.h" #include "logger.h" +#include "netutl.h" +#include "node.h" +#include "connection.h" +#include "utils.h" +#include "xalloc.h" -#include +#define MESHLINK_MDNS_SERVICE_TYPE "_%s._tcp" +#define MESHLINK_MDNS_NAME_KEY "name" +#define MESHLINK_MDNS_FINGERPRINT_KEY "fingerprint" + +#ifndef MSG_NOSIGNAL +#define MSG_NOSIGNAL 0 +#endif + +#ifndef IPV6_ADD_MEMBERSHIP +#define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP +#endif + +#ifndef IPV6_DROP_MEMBERSHIP +#define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP +#endif + +static const sockaddr_t mdns_address_ipv4 = { + .in.sin_family = AF_INET, + .in.sin_addr.s_addr = 0xfb0000e0, + .in.sin_port = 0xe914, +}; + +static const sockaddr_t mdns_address_ipv6 = { + .in6.sin6_family = AF_INET6, + .in6.sin6_addr.s6_addr[0x0] = 0xff, + .in6.sin6_addr.s6_addr[0x1] = 0x02, + .in6.sin6_addr.s6_addr[0xf] = 0xfb, + .in6.sin6_port = 0xe914, +}; + +typedef struct discovery_address { + int index; + bool up; + sockaddr_t address; + time_t last_response_sent; +} discovery_address_t; + +static int iface_compare(const void *va, const void *vb) { + const int *a = va; + const int *b = vb; + return *a - *b; +} -#include -#include -#include -#include -#include -#include -#include -#include +static int address_compare(const void *va, const void *vb) { + const discovery_address_t *a = va; + const discovery_address_t *b = vb; -#include + if(a->index != b->index) { + return a->index - b->index; + } -#include + return sockaddrcmp_noport(&a->address, &b->address); +} -#define MESHLINK_MDNS_SERVICE_TYPE "_%s._tcp" -#define MESHLINK_MDNS_NAME_KEY "name" -#define MESHLINK_MDNS_FINGERPRINT_KEY "fingerprint" +static void send_mdns_packet_ipv4(meshlink_handle_t *mesh, int fd, int index, const sockaddr_t *src, const sockaddr_t *dest, void *data, size_t len) { +#ifdef IP_MULTICAST_IF + struct ip_mreqn mreq = { + .imr_address = src->in.sin_addr, + .imr_ifindex = index, + }; -static void discovery_entry_group_callback(AvahiServer *server, AvahiSEntryGroup *group, AvahiEntryGroupState state, void *userdata) -{ - meshlink_handle_t *mesh = userdata; - - // asserts - assert(mesh != NULL); - assert(mesh->avahi_server != NULL); - assert(mesh->avahi_poll != NULL); - - /* Called whenever the entry group state changes */ - switch(state) - { - case AVAHI_ENTRY_GROUP_ESTABLISHED: - /* The entry group has been established successfully */ - logger(mesh, MESHLINK_DEBUG, "Avahi Service successfully established.\n"); - break; - - case AVAHI_ENTRY_GROUP_COLLISION: - logger(mesh, MESHLINK_WARNING, "Avahi Service collision.\n"); - // @TODO can we just set a new name and retry? - break; - - case AVAHI_ENTRY_GROUP_FAILURE : - /* Some kind of failure happened while we were registering our services */ - logger(mesh, MESHLINK_ERROR, "Avahi Entry group failure: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server))); - avahi_simple_poll_quit(mesh->avahi_poll); - break; - - case AVAHI_ENTRY_GROUP_UNCOMMITED: - case AVAHI_ENTRY_GROUP_REGISTERING: - ; - } + if(setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF, &mreq, sizeof(mreq)) != 0) { + logger(mesh, MESHLINK_ERROR, "Could not set outgoing multicast interface on IPv4 socket"); + return; + } + +#endif + +#ifdef IP_PKTINFO + struct iovec iov = { + .iov_base = data, + .iov_len = len, + }; + + struct in_pktinfo pkti = { + .ipi_ifindex = index, + .ipi_addr = src->in.sin_addr, + }; + + union { + char buf[CMSG_SPACE(sizeof(pkti))]; + struct cmsghdr align; + } u; + + memset(&u, 0, sizeof(u)); + + struct msghdr msg = { + .msg_name = (struct sockaddr *) &dest->sa, + .msg_namelen = SALEN(dest->sa), + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = u.buf, + .msg_controllen = sizeof(u.buf), + }; + + struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_level = IPPROTO_IP; + cmsg->cmsg_type = IP_PKTINFO; + cmsg->cmsg_len = CMSG_LEN(sizeof(pkti)); + memcpy(CMSG_DATA(cmsg), &pkti, sizeof(pkti)); + + // Send the packet + ssize_t result = sendmsg(fd, &msg, MSG_DONTWAIT | MSG_NOSIGNAL); +#else + (void)index; + (void)src; + + // Send the packet + ssize_t result = sendto(fd, data, len, MSG_DONTWAIT | MSG_NOSIGNAL, &dest->sa, SALEN(dest->sa)); +#endif + + if(result <= 0) { + logger(mesh, MESHLINK_ERROR, "Error sending multicast packet: %s", strerror(errno)); + } } +static void send_mdns_packet_ipv6(meshlink_handle_t *mesh, int fd, int index, const sockaddr_t *src, const sockaddr_t *dest, void *data, size_t len) { +#ifdef IPV6_MULTICAST_IF -static void discovery_create_services(meshlink_handle_t *mesh) -{ - char *txt_name = NULL; - - // asserts - assert(mesh != NULL); - assert(mesh->name != NULL); - assert(mesh->myport != NULL); - assert(mesh->avahi_server != NULL); - assert(mesh->avahi_poll != NULL); - assert(mesh->avahi_servicetype != NULL); - assert(mesh->self != NULL); - - logger(mesh, MESHLINK_DEBUG, "Adding service\n"); - - /* Ifthis is the first time we're called, let's create a new entry group */ - if(!mesh->avahi_group) - { - if(!(mesh->avahi_group = avahi_s_entry_group_new(mesh->avahi_server, discovery_entry_group_callback, mesh))) - { - logger(mesh, MESHLINK_ERROR, "avahi_entry_group_new() failed: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server))); - goto fail; - } - } - - /* Create txt records */ - size_t txt_name_len = sizeof(MESHLINK_MDNS_NAME_KEY) + 1 + strlen(mesh->name) + 1; - txt_name = malloc(txt_name_len); - - if(txt_name == NULL) - { - logger(mesh, MESHLINK_ERROR, "Could not allocate memory for TXT record\n"); - goto fail; - } - - snprintf(txt_name, txt_name_len, "%s=%s", MESHLINK_MDNS_NAME_KEY, mesh->name); - - char txt_fingerprint[sizeof(MESHLINK_MDNS_FINGERPRINT_KEY) + 1 + MESHLINK_FINGERPRINTLEN + 1]; - snprintf(txt_fingerprint, sizeof(txt_fingerprint), "%s=%s", MESHLINK_MDNS_FINGERPRINT_KEY, meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self)); - - /* Add the service */ - int ret = 0; - if((ret = avahi_server_add_service(mesh->avahi_server, mesh->avahi_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self), mesh->avahi_servicetype, NULL, NULL, atoi(mesh->myport), txt_name, txt_fingerprint, NULL)) < 0) - { - logger(mesh, MESHLINK_ERROR, "Failed to add service: %s\n", avahi_strerror(ret)); - goto fail; - } - - /* Tell the server to register the service */ - if((ret = avahi_s_entry_group_commit(mesh->avahi_group)) < 0) - { - logger(mesh, MESHLINK_ERROR, "Failed to commit entry_group: %s\n", avahi_strerror(ret)); - goto fail; - } - - goto done; - -fail: - avahi_simple_poll_quit(mesh->avahi_poll); - -done: - if(txt_name) - { free(txt_name); } + if(setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_IF, &index, sizeof(index)) != 0) { + logger(mesh, MESHLINK_ERROR, "Could not set outgoing multicast interface on IPv6 socket"); + return; + } + +#endif + +#ifdef IPV6_PKTINFO + struct iovec iov = { + .iov_base = data, + .iov_len = len, + }; + + struct in6_pktinfo pkti = { + .ipi6_ifindex = index, + .ipi6_addr = src->in6.sin6_addr, + }; + + union { + char buf[CMSG_SPACE(sizeof(pkti))]; + struct cmsghdr align; + } u; + + memset(&u, 0, sizeof u); + + struct msghdr msg = { + .msg_name = (struct sockaddr *) &dest->sa, + .msg_namelen = SALEN(dest->sa), + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = u.buf, + .msg_controllen = CMSG_LEN(sizeof(pkti)), + }; + + struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_level = IPPROTO_IPV6; + cmsg->cmsg_type = IPV6_PKTINFO; + cmsg->cmsg_len = CMSG_LEN(sizeof(pkti)); + memcpy(CMSG_DATA(cmsg), &pkti, sizeof(pkti)); + + // Send the packet + ssize_t result = sendmsg(fd, &msg, MSG_DONTWAIT | MSG_NOSIGNAL); +#else + (void)index; + (void)src; + + // Send the packet + ssize_t result = sendto(fd, data, len, MSG_DONTWAIT | MSG_NOSIGNAL, &dest->sa, SALEN(dest->sa)); +#endif + + if(result <= 0) { + logger(mesh, MESHLINK_ERROR, "Error sending multicast packet: %s", strerror(errno)); + } +} + +static void send_mdns_packet(meshlink_handle_t *mesh, discovery_address_t *addr, bool response) { + // Configure the socket to send the packet to the right interface + uint8_t msg[1024]; + size_t msg_size; + + if(response) { + char *fingerprint = meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self); + static const char *keys[] = {MESHLINK_MDNS_NAME_KEY, MESHLINK_MDNS_FINGERPRINT_KEY}; + const char *values[] = {mesh->name, fingerprint}; + msg_size = prepare_response(msg, sizeof msg, fingerprint, mesh->appname, "tcp", atoi(mesh->myport), 2, keys, values); + free(fingerprint); + addr->last_response_sent = mesh->loop.now.tv_sec; + } else { + msg_size = prepare_request(msg, sizeof msg, mesh->appname, "tcp"); + } + + switch(addr->address.sa.sa_family) { + case AF_INET: + send_mdns_packet_ipv4(mesh, mesh->discovery.sockets[0].fd, addr->index, &addr->address, &mdns_address_ipv4, msg, msg_size); + break; + + case AF_INET6: + send_mdns_packet_ipv6(mesh, mesh->discovery.sockets[1].fd, addr->index, &addr->address, &mdns_address_ipv6, msg, msg_size); + break; + + default: + break; + } +} + +static void mdns_io_handler(event_loop_t *loop, void *data, int flags) { + (void)flags; + meshlink_handle_t *mesh = loop->data; + io_t *io = data; + uint8_t buf[1024]; + sockaddr_t sa; + socklen_t sl = sizeof(sa); + +#ifdef IP_PKTINFO + struct iovec iov = { + .iov_base = buf, + .iov_len = sizeof(buf), + }; + + union { + char buf[1024]; + struct cmsghdr align; + } u; + + struct msghdr msg = { + .msg_name = &sa, + .msg_namelen = sl, + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = u.buf, + .msg_controllen = sizeof(u.buf), + }; + + ssize_t len = recvmsg(io->fd, &msg, MSG_DONTWAIT | MSG_NOSIGNAL); + + sl = msg.msg_namelen; +#else + ssize_t len = recvfrom(io->fd, buf, sizeof(buf), MSG_DONTWAIT, &sa.sa, &sl); +#endif + + if(len == -1) { + if(!sockwouldblock(errno)) { + logger(mesh, MESHLINK_ERROR, "Error reading from mDNS discovery socket: %s", strerror(errno)); + io_set(loop, io, 0); + } + + return; + } + + char *name = NULL; + uint16_t port = 0; + const char *keys[2] = {MESHLINK_MDNS_NAME_KEY, MESHLINK_MDNS_FINGERPRINT_KEY}; + char *values[2] = {NULL, NULL}; + + if(parse_response(buf, len, &name, mesh->appname, "tcp", &port, 2, keys, values)) { + node_t *n = (node_t *)meshlink_get_node(mesh, values[0]); + + if(n) { + if(n != mesh->self) { + logger(mesh, MESHLINK_INFO, "Node %s discovered on the local network.\n", n->name); + } + + switch(sa.sa.sa_family) { + case AF_INET: + sa.in.sin_port = htons(port); + break; + + case AF_INET6: + sa.in6.sin6_port = htons(port); + break; + + default: + logger(mesh, MESHLINK_WARNING, "Could not resolve node %s to a known address family type.\n", n->name); + sa.sa.sa_family = AF_UNKNOWN; + break; + } + + if(sa.sa.sa_family != AF_UNKNOWN) { + n->catta_address = sa; + n->last_connect_try = 0; + node_add_recent_address(mesh, n, &sa); + + if(n->connection) { + n->connection->last_ping_time = -3600; + } + + for list_each(outgoing_t, outgoing, mesh->outgoings) { + if(outgoing->node != n) { + continue; + } + + outgoing->timeout = 0; + + if(outgoing->ev.cb) { + timeout_set(&mesh->loop, &outgoing->ev, &(struct timespec) { + 0, 0 + }); + } + } + } + } + } else if(parse_request(buf, len, mesh->appname, "tcp")) { + char *fingerprint = meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self); + const char *response_values[] = {mesh->name, fingerprint}; + size_t size = prepare_response(buf, sizeof(buf), fingerprint, mesh->appname, "tcp", atoi(mesh->myport), 2, keys, response_values); + + int index = -1; + int family = AF_UNSPEC; + + for(struct cmsghdr *cmptr = CMSG_FIRSTHDR(&msg); cmptr != NULL; cmptr = CMSG_NXTHDR(&msg, cmptr)) { +#ifdef IP_PKTINFO + + if(cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO) { + struct in_pktinfo *pktinfo = (struct in_pktinfo *) CMSG_DATA(cmptr); + index = pktinfo->ipi_ifindex; + family = AF_INET; + break; + } else +#endif +#ifdef IPV6_PKTINFO + if(cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == IPV6_PKTINFO) { + struct in6_pktinfo *pktinfo = (struct in6_pktinfo *) CMSG_DATA(cmptr); + index = pktinfo->ipi6_ifindex; + family = AF_INET6; + break; + } + +#endif + } + + if(index) { + // Send a multicast response back using all addresses matching the interface + for(int i = 0; i < mesh->discovery.address_count; i++) { + discovery_address_t *p = &mesh->discovery.addresses[i]; + + if(p->index == index && p->address.sa.sa_family == family) { + send_mdns_packet(mesh, p, true); + } + } + } else { + // Send a unicast response back + sendto(io->fd, buf, size, MSG_DONTWAIT | MSG_NOSIGNAL, &sa.sa, sl); + } + + free(fingerprint); + } + + free(name); + + for(int i = 0; i < 2; i++) { + free(values[i]); + } } -static void discovery_server_callback(AvahiServer *server, AvahiServerState state, void * userdata) -{ - meshlink_handle_t *mesh = userdata; - - // asserts - assert(mesh != NULL); - - switch(state) - { - case AVAHI_SERVER_RUNNING: - { - /* The serve has startup successfully and registered its host - * name on the network, so it's time to create our services */ - if(!mesh->avahi_group) - { - discovery_create_services(mesh); - } - } - break; - - case AVAHI_SERVER_COLLISION: - { - // asserts - assert(mesh->avahi_server != NULL); - assert(mesh->avahi_poll != NULL); - - /* A host name collision happened. Let's pick a new name for the server */ - uuid_t hostname; - uuid_generate(hostname); - - char hostnamestr[36+1]; - uuid_unparse_lower(hostname, hostnamestr); - - logger(mesh, MESHLINK_WARNING, "Avahi host name collision, retrying with '%s'\n", hostnamestr); - int result = avahi_server_set_host_name(mesh->avahi_server, hostnamestr); - - if(result < 0) - { - logger(mesh, MESHLINK_ERROR, "Avahi failed to set new host name: %s\n", avahi_strerror(result)); - avahi_simple_poll_quit(mesh->avahi_poll); - return; - } - } - break; - - case AVAHI_SERVER_REGISTERING: - { - /* Let's drop our registered services. When the server is back - * in AVAHI_SERVER_RUNNING state we will register them - * again with the new host name. */ - if(mesh->avahi_group) - { - avahi_s_entry_group_reset(mesh->avahi_group); - mesh->avahi_group = NULL; - } - } - break; - - case AVAHI_SERVER_FAILURE: - { - // asserts - assert(mesh->avahi_server != NULL); - assert(mesh->avahi_poll != NULL); - - /* Terminate on failure */ - logger(mesh, MESHLINK_ERROR, "Avahi server failure: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server))); - avahi_simple_poll_quit(mesh->avahi_poll); - } - break; - - case AVAHI_SERVER_INVALID: - break; - } +static void iface_up(meshlink_handle_t *mesh, int index) { + int *p = bsearch(&index, mesh->discovery.ifaces, mesh->discovery.iface_count, sizeof(*p), iface_compare); + + if(p) { + return; + } + + mesh->discovery.ifaces = xrealloc(mesh->discovery.ifaces, ++mesh->discovery.iface_count * sizeof(*p)); + mesh->discovery.ifaces[mesh->discovery.iface_count - 1] = index; + qsort(mesh->discovery.ifaces, mesh->discovery.iface_count, sizeof(*p), iface_compare); + + // Add multicast membership + struct ip_mreqn mreq4 = { + .imr_multiaddr = mdns_address_ipv4.in.sin_addr, + .imr_ifindex = index, + }; + + setsockopt(mesh->discovery.sockets[0].fd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreq4, sizeof(mreq4)); + setsockopt(mesh->discovery.sockets[0].fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq4, sizeof(mreq4)); + + struct ipv6_mreq mreq6 = { + .ipv6mr_multiaddr = mdns_address_ipv6.in6.sin6_addr, + .ipv6mr_interface = index, + }; + + setsockopt(mesh->discovery.sockets[1].fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)); + setsockopt(mesh->discovery.sockets[1].fd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)); + + // Send an announcement for all addresses associated with this interface + for(int i = 0; i < mesh->discovery.address_count; i++) { + if(mesh->discovery.addresses[i].index == index) { + send_mdns_packet(mesh, &mesh->discovery.addresses[i], false); + } + } + + handle_network_change(mesh, true); } -static void discovery_resolve_callback(AvahiSServiceResolver *resolver, AvahiIfIndex interface, AvahiProtocol protocol, AvahiResolverEvent event, const char *name, const char *type, const char *domain, const char *host_name, const AvahiAddress *address, uint16_t port, AvahiStringList *txt, AvahiLookupResultFlags flags, void* userdata) -{ - meshlink_handle_t *mesh = userdata; - - // asserts - assert(resolver != NULL); - assert(mesh != NULL); - assert(mesh->avahi_server != NULL); - - /* Called whenever a service has been resolved successfully or timed out */ - switch(event) - { - case AVAHI_RESOLVER_FAILURE: - { - // asserts - assert(name != NULL); - assert(type != NULL); - assert(domain != NULL); - - logger(mesh, MESHLINK_WARNING, "(Resolver) Failed to resolve service '%s' of type '%s' in domain '%s': %s\n", name, type, domain, avahi_strerror(avahi_server_errno(mesh->avahi_server))); - } - break; - - case AVAHI_RESOLVER_FOUND: - { - // asserts - assert(name != NULL); - assert(type != NULL); - assert(domain != NULL); - assert(host_name != NULL); - assert(address != NULL); - assert(txt != NULL); - - char straddr[AVAHI_ADDRESS_STR_MAX], *strtxt; - - logger(mesh, MESHLINK_DEBUG, "(Resolver) Service '%s' of type '%s' in domain '%s':\n", name, type, domain); - - avahi_address_snprint(straddr, sizeof(straddr), address); - strtxt = avahi_string_list_to_string(txt); - logger(mesh, MESHLINK_DEBUG, - "\t%s:%u (%s)\n" - "\tTXT=%s\n" - "\tcookie is %u\n" - "\tis_local: %i\n" - "\twide_area: %i\n" - "\tmulticast: %i\n" - "\tcached: %i\n", - host_name, port, straddr, - strtxt, - avahi_string_list_get_service_cookie(txt), - !!(flags & AVAHI_LOOKUP_RESULT_LOCAL), - !!(flags & AVAHI_LOOKUP_RESULT_WIDE_AREA), - !!(flags & AVAHI_LOOKUP_RESULT_MULTICAST), - !!(flags & AVAHI_LOOKUP_RESULT_CACHED)); - avahi_free(strtxt); - - // retrieve fingerprint - AvahiStringList *node_name_li = avahi_string_list_find(txt, MESHLINK_MDNS_NAME_KEY); - AvahiStringList *node_fp_li = avahi_string_list_find(txt, MESHLINK_MDNS_FINGERPRINT_KEY); - - if(node_name_li != NULL && node_fp_li != NULL) - { - char *node_name = (char*)avahi_string_list_get_text(node_name_li) + strlen(MESHLINK_MDNS_NAME_KEY); - char *node_fp = (char*)avahi_string_list_get_text(node_fp_li) + strlen(MESHLINK_MDNS_FINGERPRINT_KEY); - - if(node_name[0] == '=' && node_fp[0] == '=') - { - node_name += 1; - node_fp += 1; - - meshlink_node_t *node = meshlink_get_node(mesh, node_name); - - if(node != NULL) - { - logger(mesh, MESHLINK_INFO, "Node %s is part of the mesh network.\n", node->name); - - sockaddr_t naddress; - memset(&naddress, 0, sizeof(naddress)); - - switch(address->proto) - { - case AVAHI_PROTO_INET: - { - naddress.in.sin_family = AF_INET; - naddress.in.sin_port = htons(port); - naddress.in.sin_addr.s_addr = address->data.ipv4.address; - } - break; - - case AVAHI_PROTO_INET6: - { - naddress.in6.sin6_family = AF_INET6; - naddress.in6.sin6_port = htons(port); - memcpy(naddress.in6.sin6_addr.s6_addr, address->data.ipv6.address, sizeof(naddress.in6.sin6_addr.s6_addr)); - } - break; - - default: - naddress.unknown.family = AF_UNKNOWN; - break; - } - - if(naddress.unknown.family != AF_UNKNOWN) - { - meshlink_hint_address(mesh, (meshlink_node_t *)node, (struct sockaddr*)&naddress); - } - else - { - logger(mesh, MESHLINK_WARNING, "Could not resolve node %s to a known address family type.\n", node->name); - } - } - else - { - logger(mesh, MESHLINK_WARNING, "Node %s is not part of the mesh network.\n", node_name); - } - } - else - { - logger(mesh, MESHLINK_WARNING, "TXT records invalid.\n"); - } - } - else - { - logger(mesh, MESHLINK_WARNING, "TXT records missing.\n"); - } - } - break; - } - - avahi_s_service_resolver_free(resolver); +static void iface_down(meshlink_handle_t *mesh, int index) { + int *p = bsearch(&index, mesh->discovery.ifaces, mesh->discovery.iface_count, sizeof(*p), iface_compare); + + if(!p) { + return; + } + + // Drop multicast membership + struct ip_mreqn mreq4 = { + .imr_multiaddr = mdns_address_ipv4.in.sin_addr, + .imr_ifindex = index, + }; + setsockopt(mesh->discovery.sockets[0].fd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreq4, sizeof(mreq4)); + + struct ipv6_mreq mreq6 = { + .ipv6mr_multiaddr = mdns_address_ipv6.in6.sin6_addr, + .ipv6mr_interface = index, + }; + setsockopt(mesh->discovery.sockets[1].fd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)); + + memmove(p, p + 1, (mesh->discovery.ifaces + --mesh->discovery.iface_count - p) * sizeof(*p)); + + handle_network_change(mesh, mesh->discovery.iface_count); } -static void discovery_browse_callback(AvahiSServiceBrowser *browser, AvahiIfIndex interface, AvahiProtocol protocol, AvahiBrowserEvent event, const char *name, const char *type, const char *domain, AvahiLookupResultFlags flags, void* userdata) -{ - meshlink_handle_t *mesh = userdata; - - // asserts - assert(mesh != NULL); - assert(mesh->avahi_server != NULL); - assert(mesh->avahi_poll != NULL); - - /* Called whenever a new services becomes available on the LAN or is removed from the LAN */ - switch (event) - { - case AVAHI_BROWSER_FAILURE: - { - logger(mesh, MESHLINK_ERROR, "(Browser) %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server))); - avahi_simple_poll_quit(mesh->avahi_poll); - } - return; - - case AVAHI_BROWSER_NEW: - { - // asserts - assert(name != NULL); - assert(type != NULL); - assert(domain != NULL); - - logger(mesh, MESHLINK_DEBUG, "(Browser) NEW: service '%s' of type '%s' in domain '%s'\n", name, type, domain); - /* We ignore the returned resolver object. In the callback - function we free it. Ifthe server is terminated before - the callback function is called the server will free - the resolver for us. */ - if(!(avahi_s_service_resolver_new(mesh->avahi_server, interface, protocol, name, type, domain, AVAHI_PROTO_UNSPEC, 0, discovery_resolve_callback, mesh))) - { - logger(mesh, MESHLINK_DEBUG, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(mesh->avahi_server))); - } - } - break; - - case AVAHI_BROWSER_REMOVE: - { - // asserts - assert(name != NULL); - assert(type != NULL); - assert(domain != NULL); - - logger(mesh, MESHLINK_DEBUG, "(Browser) REMOVE: service '%s' of type '%s' in domain '%s'\n", name, type, domain); - } - break; - - case AVAHI_BROWSER_ALL_FOR_NOW: - case AVAHI_BROWSER_CACHE_EXHAUSTED: - { - logger(mesh, MESHLINK_DEBUG, "(Browser) %s\n", event == AVAHI_BROWSER_CACHE_EXHAUSTED ? "CACHE_EXHAUSTED" : "ALL_FOR_NOW"); - } - break; - } +static void addr_add(meshlink_handle_t *mesh, const discovery_address_t *addr) { + discovery_address_t *p = bsearch(addr, mesh->discovery.addresses, mesh->discovery.address_count, sizeof(*p), address_compare); + + if(p) { + return; + } + + bool up = bsearch(&addr->index, mesh->discovery.ifaces, mesh->discovery.iface_count, sizeof(int), iface_compare); + + mesh->discovery.addresses = xrealloc(mesh->discovery.addresses, ++mesh->discovery.address_count * sizeof(*p)); + mesh->discovery.addresses[mesh->discovery.address_count - 1] = *addr; + mesh->discovery.addresses[mesh->discovery.address_count - 1].up = up; + + if(up) { + send_mdns_packet(mesh, &mesh->discovery.addresses[mesh->discovery.address_count - 1], false); + } + + qsort(mesh->discovery.addresses, mesh->discovery.address_count, sizeof(*p), address_compare); } -static void *discovery_loop(void *userdata) -{ - meshlink_handle_t *mesh = userdata; +static void addr_del(meshlink_handle_t *mesh, const discovery_address_t *addr) { + discovery_address_t *p = bsearch(addr, mesh->discovery.addresses, mesh->discovery.address_count, sizeof(*p), address_compare); - // asserts - assert(mesh != NULL); - assert(mesh->avahi_poll != NULL); + if(!p) { + return; + } - avahi_simple_poll_loop(mesh->avahi_poll); - - return NULL; + memmove(p, p + 1, (mesh->discovery.addresses + --mesh->discovery.address_count - p) * sizeof(*p)); } -static void discovery_log_cb(AvahiLogLevel level, const char *txt) -{ - meshlink_log_level_t mlevel = MESHLINK_CRITICAL; +void scan_ifaddrs(meshlink_handle_t *mesh) { +#ifdef HAVE_GETIFADDRS + struct ifaddrs *ifa = NULL; + + if(getifaddrs(&ifa) == -1) { + logger(mesh, MESHLINK_ERROR, "Could not get list of interface addresses: %s", strerror(errno)); + return; + } - switch(level) - { - case AVAHI_LOG_ERROR: - mlevel = MESHLINK_ERROR; - break; + // Check for interfaces being removed + for(int i = 0; i < mesh->discovery.iface_count;) { + bool found = false; - case AVAHI_LOG_WARN: - mlevel = MESHLINK_WARNING; - break; + for(struct ifaddrs *ifap = ifa; ifap; ifap = ifap->ifa_next) { + if(!ifap->ifa_name) { + continue; + } - case AVAHI_LOG_NOTICE: - case AVAHI_LOG_INFO: - mlevel = MESHLINK_INFO; - break; + int index = if_nametoindex(ifap->ifa_name); - case AVAHI_LOG_DEBUG: - mlevel = MESHLINK_DEBUG; - break; - } + if(mesh->discovery.ifaces[i] == index) { + found = true; + break; + } + } - logger(NULL, mlevel, "%s\n", txt); + if(!found) { + iface_down(mesh, mesh->discovery.ifaces[i]); + } else { + i++; + } + } + + // Check for addresses being removed + for(int i = 0; i < mesh->discovery.address_count;) { + discovery_address_t *p = &mesh->discovery.addresses[i]; + bool found = false; + + for(struct ifaddrs *ifap = ifa; ifap; ifap = ifap->ifa_next) { + if(!ifap->ifa_name || !ifap->ifa_addr) { + continue; + } + + int index = if_nametoindex(ifap->ifa_name); + + if(p->index == index && sockaddrcmp_noport(&p->address, (sockaddr_t *)ifap->ifa_addr) == 0) { + found = true; + break; + } + } + + if(!found) { + (void)addr_del; + memmove(p, p + 1, (mesh->discovery.addresses + --mesh->discovery.address_count - p) * sizeof(*p)); + } else { + i++; + } + } + + // Check for interfaces state changes and addresses going up + for(struct ifaddrs *ifap = ifa; ifap; ifap = ifap->ifa_next) { + if(!ifap->ifa_name) { + continue; + } + + int index = if_nametoindex(ifap->ifa_name); + + if(ifap->ifa_flags & IFF_UP && ifap->ifa_flags & IFF_MULTICAST && !(ifap->ifa_flags & IFF_LOOPBACK)) { + iface_up(mesh, index); + } else { + iface_down(mesh, index); + } + + if(!ifap->ifa_addr) { + continue; + } + + discovery_address_t addr = { + .index = index, + }; + + sockaddr_t *sa = (sockaddr_t *)ifap->ifa_addr; + + if(sa->sa.sa_family == AF_INET) { + memcpy(&addr.address.in, &sa->in, sizeof(sa->in)); + addr.address.in.sin_port = ntohs(5353); + } else if(sa->sa.sa_family == AF_INET6) { + memcpy(&addr.address.in6, &sa->in6, sizeof(sa->in6)); + addr.address.in6.sin6_port = ntohs(5353); + } else { + addr.address.sa.sa_family = AF_UNKNOWN; + } + + if(addr.address.sa.sa_family != AF_UNKNOWN) { + addr_add(mesh, &addr); + } + } + + freeifaddrs(ifa); +#else + (void)mesh; +#endif +} + +#if defined(__linux) +static void netlink_getlink(int fd) { + static const struct { + struct nlmsghdr nlm; + struct ifinfomsg ifi; + } msg = { + .nlm.nlmsg_len = NLMSG_LENGTH(sizeof(msg.ifi)), + .nlm.nlmsg_type = RTM_GETLINK, + .nlm.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, + .nlm.nlmsg_seq = 1, + .ifi.ifi_family = AF_UNSPEC, + }; + send(fd, &msg, msg.nlm.nlmsg_len, 0); } -bool discovery_start(meshlink_handle_t *mesh) -{ - logger(mesh, MESHLINK_DEBUG, "discovery_start called\n"); - - // asserts - assert(mesh != NULL); - assert(mesh->avahi_poll == NULL); - assert(mesh->avahi_server == NULL); - assert(mesh->avahi_browser == NULL); - assert(mesh->discovery_threadstarted == false); - assert(mesh->avahi_servicetype == NULL); - - // handle avahi logs - avahi_set_log_function(discovery_log_cb); - - // create service type string - size_t servicetype_strlen = sizeof(MESHLINK_MDNS_SERVICE_TYPE) + strlen(mesh->appname) + 1; - mesh->avahi_servicetype = malloc(servicetype_strlen); - - if(mesh->avahi_servicetype == NULL) - { - logger(mesh, MESHLINK_ERROR, "Failed to allocate memory for service type string.\n"); - goto fail; - } - - snprintf(mesh->avahi_servicetype, servicetype_strlen, MESHLINK_MDNS_SERVICE_TYPE, mesh->appname); - - // Allocate discovery loop object - if(!(mesh->avahi_poll = avahi_simple_poll_new())) - { - logger(mesh, MESHLINK_ERROR, "Failed to create discovery poll object.\n"); - goto fail; - } - - // generate some unique host name (we actually do not care about it) - uuid_t hostname; - uuid_generate(hostname); - - char hostnamestr[36+1]; - uuid_unparse_lower(hostname, hostnamestr); - - // Let's set the host name for this server. - AvahiServerConfig config; - avahi_server_config_init(&config); - config.host_name = avahi_strdup(hostnamestr); - config.publish_workstation = 0; - config.disallow_other_stacks = 0; - config.publish_hinfo = 0; - config.publish_addresses = 1; - config.publish_no_reverse = 1; - - /* Allocate a new server */ - int error; - mesh->avahi_server = avahi_server_new(avahi_simple_poll_get(mesh->avahi_poll), &config, discovery_server_callback, mesh, &error); - - /* Free the configuration data */ - avahi_server_config_free(&config); - - /* Check wether creating the server object succeeded */ - if(!mesh->avahi_server) - { - logger(mesh, MESHLINK_ERROR, "Failed to create discovery server: %s\n", avahi_strerror(error)); - goto fail; - } - - // Create the service browser - if(!(mesh->avahi_browser = avahi_s_service_browser_new(mesh->avahi_server, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, mesh->avahi_servicetype, NULL, 0, discovery_browse_callback, mesh))) - { - logger(mesh, MESHLINK_ERROR, "Failed to create discovery service browser: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server))); - goto fail; - } - - // Start the discovery thread - if(pthread_create(&mesh->discovery_thread, NULL, discovery_loop, mesh) != 0) - { - logger(mesh, MESHLINK_ERROR, "Could not start discovery thread: %s\n", strerror(errno)); - memset(&mesh->discovery_thread, 0, sizeof mesh->discovery_thread); - goto fail; - } - - mesh->discovery_threadstarted = true; +static void netlink_getaddr(int fd) { + static const struct { + struct nlmsghdr nlm; + struct ifaddrmsg ifa; + } msg = { + .nlm.nlmsg_len = NLMSG_LENGTH(sizeof(msg.ifa)), + .nlm.nlmsg_type = RTM_GETADDR, + .nlm.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST, + .nlm.nlmsg_seq = 2, + .ifa.ifa_family = AF_UNSPEC, + }; + send(fd, &msg, msg.nlm.nlmsg_len, 0); +} + +static void netlink_parse_link(meshlink_handle_t *mesh, const struct nlmsghdr *nlm) { + const struct ifinfomsg *ifi = (const struct ifinfomsg *)(nlm + 1); + + if(ifi->ifi_flags & IFF_UP && ifi->ifi_flags & IFF_MULTICAST) { + iface_up(mesh, ifi->ifi_index); + } else { + iface_down(mesh, ifi->ifi_index); + } +} + +static void netlink_parse_addr(meshlink_handle_t *mesh, const struct nlmsghdr *nlm) { + const struct ifaddrmsg *ifa = (const struct ifaddrmsg *)(nlm + 1); + const uint8_t *ptr = (const uint8_t *)(ifa + 1); + size_t len = nlm->nlmsg_len - (ptr - (const uint8_t *)nlm); + + while(len >= sizeof(struct rtattr)) { + const struct rtattr *rta = (const struct rtattr *)ptr; + + if(rta->rta_len <= 0 || rta->rta_len > len) { + break; + } + + if(rta->rta_type == IFA_ADDRESS) { + discovery_address_t addr = { + .index = ifa->ifa_index, + }; + + if(rta->rta_len == 8) { + addr.address.sa.sa_family = AF_INET; + memcpy(&addr.address.in.sin_addr, ptr + 4, 4); + addr.address.in.sin_port = ntohs(5353); + } else if(rta->rta_len == 20) { + addr.address.sa.sa_family = AF_INET6; + memcpy(&addr.address.in6.sin6_addr, ptr + 4, 16); + addr.address.in6.sin6_port = ntohs(5353); + addr.address.in6.sin6_scope_id = ifa->ifa_index; + } else { + addr.address.sa.sa_family = AF_UNKNOWN; + } + + if(addr.address.sa.sa_family != AF_UNKNOWN) { + if(nlm->nlmsg_type == RTM_NEWADDR) { + addr_add(mesh, &addr); + } else { + addr_del(mesh, &addr); + } + } + } + + unsigned short rta_len = (rta->rta_len + 3) & ~3; + ptr += rta_len; + len -= rta_len; + } +} + +static void netlink_parse(meshlink_handle_t *mesh, const void *data, size_t len) { + const uint8_t *ptr = data; + + while(len >= sizeof(struct nlmsghdr)) { + const struct nlmsghdr *nlm = (const struct nlmsghdr *)ptr; + + if(nlm->nlmsg_len > len) { + break; + } + + switch(nlm->nlmsg_type) { + case RTM_NEWLINK: + case RTM_DELLINK: + netlink_parse_link(mesh, nlm); + break; + + case RTM_NEWADDR: + case RTM_DELADDR: + netlink_parse_addr(mesh, nlm); + } + + ptr += nlm->nlmsg_len; + len -= nlm->nlmsg_len; + } +} + +static void netlink_io_handler(event_loop_t *loop, void *data, int flags) { + (void)flags; + (void)data; + meshlink_handle_t *mesh = loop->data; + + struct { + struct nlmsghdr nlm; + char data[16384]; + } msg; + + while(true) { + ssize_t result = recv(mesh->discovery.pfroute_io.fd, &msg, sizeof(msg), MSG_DONTWAIT); + + if(result <= 0) { + if(result == 0 || errno == EAGAIN || errno == EINTR) { + break; + } + + logger(mesh, MESHLINK_ERROR, "Reading from Netlink socket failed: %s\n", strerror(errno)); + io_set(loop, &mesh->discovery.pfroute_io, 0); + } + + if((size_t)result < sizeof(msg.nlm)) { + logger(mesh, MESHLINK_ERROR, "Invalid Netlink message\n"); + break; + } + + if(msg.nlm.nlmsg_type == NLMSG_DONE) { + if(msg.nlm.nlmsg_seq == 1) { + // We just got the result of GETLINK, now send GETADDR. + netlink_getaddr(mesh->discovery.pfroute_io.fd); + } + } else { + netlink_parse(mesh, &msg, result); + + if(loop->now.tv_sec > mesh->discovery.last_update + 5) { + mesh->discovery.last_update = loop->now.tv_sec; + handle_network_change(mesh, true); + } + } + } +} +#elif defined(__APPLE__) +static void reachability_change_callback(SCNetworkReachabilityRef reachability, SCNetworkReachabilityFlags flags, void *info) { + (void)reachability; + (void)flags; + + meshlink_handle_t *mesh = info; + + pthread_mutex_lock(&mesh->mutex); + + scan_ifaddrs(mesh); + + if(mesh->loop.now.tv_sec > mesh->discovery.last_update + 5) { + logger(mesh, MESHLINK_INFO, "Network change detected"); + mesh->discovery.last_update = mesh->loop.now.tv_sec; + handle_network_change(mesh, true); + } + + pthread_mutex_unlock(&mesh->mutex); +} + +static void *network_change_handler(void *arg) { + meshlink_handle_t *mesh = arg; + + mesh->discovery.runloop = CFRunLoopGetCurrent(); + + SCNetworkReachabilityRef reach_v4 = SCNetworkReachabilityCreateWithName(NULL, "93.184.216.34"); + SCNetworkReachabilityRef reach_v6 = SCNetworkReachabilityCreateWithName(NULL, "2606:2800:220:1:248:1893:25c8:1946"); + + SCNetworkReachabilityContext context; + memset(&context, 0, sizeof(context)); + context.info = mesh; + + if(reach_v4) { + SCNetworkReachabilitySetCallback(reach_v4, reachability_change_callback, &context); + SCNetworkReachabilityScheduleWithRunLoop(reach_v4, mesh->discovery.runloop, kCFRunLoopDefaultMode); + } else { + logger(mesh, MESHLINK_ERROR, "Could not create IPv4 network reachability watcher"); + } + + if(reach_v6) { + SCNetworkReachabilitySetCallback(reach_v6, reachability_change_callback, &context); + SCNetworkReachabilityScheduleWithRunLoop(reach_v6, mesh->discovery.runloop, kCFRunLoopDefaultMode); + } else { + logger(mesh, MESHLINK_ERROR, "Could not create IPv6 network reachability watcher"); + } + + CFRunLoopRun(); + + mesh->discovery.runloop = NULL; + + if(reach_v4) { + SCNetworkReachabilityUnscheduleFromRunLoop(reach_v4, mesh->discovery.runloop, kCFRunLoopDefaultMode); + CFRelease(reach_v4); + } + + if(reach_v6) { + SCNetworkReachabilityUnscheduleFromRunLoop(reach_v6, mesh->discovery.runloop, kCFRunLoopDefaultMode); + CFRelease(reach_v6); + } + + return NULL; +} +#elif defined(RTM_NEWADDR) +static void pfroute_parse_iface(meshlink_handle_t *mesh, const struct rt_msghdr *rtm) { + const struct if_msghdr *ifm = (const struct if_msghdr *)rtm; + + if(ifm->ifm_flags & IFF_UP && ifm->ifm_flags & IFF_MULTICAST && !(ifm->ifm_flags & IFF_LOOPBACK)) { + iface_up(mesh, ifm->ifm_index); + } else { + iface_down(mesh, ifm->ifm_index); + } +} + +static void pfroute_parse_addr(meshlink_handle_t *mesh, const struct rt_msghdr *rtm) { + const struct ifa_msghdr *ifam = (const struct ifa_msghdr *)rtm; + const char *p = (const char *)(ifam + 1); + + for(unsigned int i = 1; i; i <<= 1) { + if(!(ifam->ifam_addrs & i)) { + continue; + } + + const sockaddr_t *sa = (const sockaddr_t *)p; + + if(i == RTA_IFA) { + discovery_address_t addr = { + .index = ifam->ifam_index, + }; + + if(sa->sa.sa_family == AF_INET) { + addr.address.in = sa->in; + addr.address.in.sin_port = ntohs(5353); + } else if(sa->sa.sa_family == AF_INET6) { + addr.address.in6 = sa->in6; + addr.address.in6.sin6_port = ntohs(5353); + } else { + addr.address.sa.sa_family = AF_UNKNOWN; + } + + if(addr.address.sa.sa_family != AF_UNKNOWN) { + if(ifam->ifam_type == RTM_NEWADDR) { + addr_add(mesh, &addr); + } else { + addr_del(mesh, &addr); + } + } + + break; + } + + size_t len = (sa->sa.sa_len + 3) & ~3; + p += len; + } +} + +static void pfroute_io_handler(event_loop_t *loop, void *data, int flags) { + (void)flags; + (void)data; + meshlink_handle_t *mesh = loop->data; + + struct { + struct rt_msghdr rtm; + char data[2048]; + } msg; + + while(true) { + msg.rtm.rtm_version = 0; + ssize_t result = recv(mesh->discovery.pfroute_io.fd, &msg, sizeof(msg), MSG_DONTWAIT); + + if(result <= 0) { + if(result == 0 || errno == EAGAIN || errno == EINTR) { + break; + } + + logger(mesh, MESHLINK_ERROR, "Reading from PFROUTE socket failed: %s\n", strerror(errno)); + io_set(loop, &mesh->discovery.pfroute_io, 0); + } + + if(msg.rtm.rtm_version != RTM_VERSION) { + logger(mesh, MESHLINK_ERROR, "Invalid PFROUTE message version\n"); + break; + } + + switch(msg.rtm.rtm_type) { + case RTM_IFINFO: + pfroute_parse_iface(mesh, &msg.rtm); + break; + + case RTM_NEWADDR: + case RTM_DELADDR: + pfroute_parse_addr(mesh, &msg.rtm); + break; + + default: + break; + } + } +} +#endif + +bool discovery_start(meshlink_handle_t *mesh) { + logger(mesh, MESHLINK_DEBUG, "discovery_start called\n"); + + assert(mesh); + + // Set up multicast sockets for mDNS + static const int one = 1; + static const int ttl = 255; + static const uint8_t one8 = 1; + static const uint8_t ttl8 = 255; + + int fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); + + if(fd == -1) { + logger(mesh, MESHLINK_ERROR, "Error creating IPv4 socket: %s", strerror(errno)); + } else { + + sockaddr_t sa4 = { + .in.sin_family = AF_INET, + .in.sin_port = ntohs(5353), + }; + setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); +#ifdef SO_REUSEPORT + setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one)); +#endif +#ifdef IP_PKTINFO + setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one)); +#endif + setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one8, sizeof(one8)); + setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl8, sizeof(ttl8)); + + if(bind(fd, &sa4.sa, SALEN(sa4.sa)) == -1) { + logger(mesh, MESHLINK_ERROR, "Error binding to IPv4 multicast socket: %s", strerror(errno)); + } else { + io_add(&mesh->loop, &mesh->discovery.sockets[0], mdns_io_handler, &mesh->discovery.sockets[0], fd, IO_READ); + } + } + + fd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP); + + if(fd == -1) { + logger(mesh, MESHLINK_ERROR, "Error creating IPv6 socket: %s", strerror(errno)); + } else { + sockaddr_t sa6 = { + .in6.sin6_family = AF_INET6, + .in6.sin6_port = ntohs(5353), + }; + + setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); +#ifdef SO_REUSEPORT + setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one)); +#endif +#ifdef IPV6_RECVPKTINFO + setsockopt(fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one)); +#endif + setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one)); + setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one)); + setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)); + setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)); + + if(bind(fd, &sa6.sa, SALEN(sa6.sa)) == -1) { + logger(mesh, MESHLINK_ERROR, "Error binding to IPv6 multicast socket: %s", strerror(errno)); + } else { + io_add(&mesh->loop, &mesh->discovery.sockets[1], mdns_io_handler, &mesh->discovery.sockets[1], fd, IO_READ); + } + } + +#if defined(__linux) + int sock = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE); + + if(sock != -1) { + struct sockaddr_nl sa; + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + sa.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR; + + if(bind(sock, (struct sockaddr *)&sa, sizeof(sa)) != -1) { + io_add(&mesh->loop, &mesh->discovery.pfroute_io, netlink_io_handler, NULL, sock, IO_READ); + netlink_getlink(sock); + } else { + logger(mesh, MESHLINK_WARNING, "Could not bind AF_NETLINK socket: %s", strerror(errno)); + scan_ifaddrs(mesh); + } + } else { + logger(mesh, MESHLINK_WARNING, "Could not open AF_NETLINK socket: %s", strerror(errno)); + scan_ifaddrs(mesh); + } + +#elif defined(__APPLE__) + pthread_create(&mesh->discovery.thread, NULL, network_change_handler, mesh); + // TODO: Do we need to wait for the thread to start succesfully? + scan_ifaddrs(mesh); +#elif defined(RTM_NEWADDR) + int sock = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC); + + if(sock != -1) { + io_add(&mesh->loop, &mesh->discovery.pfroute_io, pfroute_io_handler, NULL, sock, IO_READ); + } else { + logger(mesh, MESHLINK_WARNING, "Could not open PF_ROUTE socket: %s", strerror(errno)); + } + + scan_ifaddrs(mesh); +#endif return true; +} + +void discovery_stop(meshlink_handle_t *mesh) { + logger(mesh, MESHLINK_DEBUG, "discovery_stop called\n"); + + assert(mesh); + + free(mesh->discovery.ifaces); + free(mesh->discovery.addresses); + mesh->discovery.ifaces = NULL; + mesh->discovery.addresses = NULL; + mesh->discovery.iface_count = 0; + mesh->discovery.address_count = 0; -fail: - if(mesh->avahi_browser != NULL) - { - avahi_s_service_browser_free(mesh->avahi_browser); - mesh->avahi_browser = NULL; - } - - if(mesh->avahi_server != NULL) - { - avahi_server_free(mesh->avahi_server); - mesh->avahi_server = NULL; - } - - if(mesh->avahi_poll != NULL) - { - avahi_simple_poll_free(mesh->avahi_poll); - mesh->avahi_poll = NULL; - } - - if(mesh->avahi_servicetype != NULL) - { - free(mesh->avahi_servicetype); - mesh->avahi_servicetype = NULL; - } - - return false; +#if defined(__APPLE__) + + if(mesh->discovery.runloop) { + CFRunLoopStop(mesh->discovery.runloop); + pthread_join(mesh->discovery.thread, NULL); + } + +#endif + + if(mesh->discovery.pfroute_io.cb) { + close(mesh->discovery.pfroute_io.fd); + io_del(&mesh->loop, &mesh->discovery.pfroute_io); + } + + for(int i = 0; i < 2; i++) { + if(mesh->discovery.sockets[i].cb) { + close(mesh->discovery.sockets[i].fd); + io_del(&mesh->loop, &mesh->discovery.sockets[i]); + } + } } -void discovery_stop(meshlink_handle_t *mesh) -{ - logger(mesh, MESHLINK_DEBUG, "discovery_stop called\n"); - - // asserts - assert(mesh != NULL); - - // Shut down - if(mesh->avahi_poll) - { - avahi_simple_poll_quit(mesh->avahi_poll); - } - - // Wait for the discovery thread to finish - if(mesh->discovery_threadstarted == true) - { - pthread_join(mesh->discovery_thread, NULL); - mesh->discovery_threadstarted = false; - } - - // Clean up resources - if(mesh->avahi_browser != NULL) - { - avahi_s_service_browser_free(mesh->avahi_browser); - mesh->avahi_browser = NULL; - } - - if(mesh->avahi_group) - { - avahi_s_entry_group_reset(mesh->avahi_group); - avahi_s_entry_group_free(mesh->avahi_group); - mesh->avahi_group = NULL; - } - - if(mesh->avahi_server != NULL) - { - avahi_server_free(mesh->avahi_server); - mesh->avahi_server = NULL; - } - - if(mesh->avahi_poll != NULL) - { - avahi_simple_poll_free(mesh->avahi_poll); - mesh->avahi_poll = NULL; - } - - if(mesh->avahi_servicetype != NULL) - { - free(mesh->avahi_servicetype); - mesh->avahi_servicetype = NULL; - } +void discovery_refresh(meshlink_handle_t *mesh) { + for(int i = 0; i < mesh->discovery.address_count; i++) { + if(mesh->discovery.addresses[i].up) { + send_mdns_packet(mesh, &mesh->discovery.addresses[i], false); + } + } }