-
+/*
+ discovery.c -- local network discovery
+ Copyright (C) 2014-2021 Guus Sliepen <guus@meshlink.io>
+
+ 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 <CoreFoundation/CoreFoundation.h>
+#include <CoreFoundation/CFArray.h>
+#include <CoreFoundation/CFString.h>
+#include <SystemConfiguration/SystemConfiguration.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#elif defined(__unix) && !defined(__linux)
+#include <net/if.h>
+#include <net/route.h>
+#include <netinet/in.h>
+#elif defined(__linux)
+#include <asm/types.h>
+#include <net/if.h>
+#include <linux/if_link.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#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 <pthread.h>
+#define MESHLINK_MDNS_SERVICE_TYPE "_%s._tcp"
+#define MESHLINK_MDNS_NAME_KEY "name"
+#define MESHLINK_MDNS_FINGERPRINT_KEY "fingerprint"
-#include <avahi-core/core.h>
-#include <avahi-core/lookup.h>
-#include <avahi-core/publish.h>
-#include <avahi-common/simple-watch.h>
-#include <avahi-common/malloc.h>
-#include <avahi-common/alternative.h>
-#include <avahi-common/error.h>
+#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 <netinet/in.h>
+static int address_compare(const void *va, const void *vb) {
+ const discovery_address_t *a = va;
+ const discovery_address_t *b = vb;
-#include <uuid/uuid.h>
+ if(a->index != b->index) {
+ return a->index - b->index;
+ }
-#define MESHLINK_MDNS_SERVICE_TYPE "_%s._tcp"
-#define MESHLINK_MDNS_NAME_KEY "name"
-#define MESHLINK_MDNS_FINGERPRINT_KEY "fingerprint"
+ return sockaddrcmp_noport(&a->address, &b->address);
+}
+
+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,
+ };
+
+ 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
+
+ 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 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 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 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 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);
+
+ if(!p) {
+ return;
+ }
+
+ memmove(p, p + 1, (mesh->discovery.addresses + --mesh->discovery.address_count - p) * sizeof(*p));
+}
+
+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;
+ }
+
+ // Check for interfaces being removed
+ for(int i = 0; i < mesh->discovery.iface_count;) {
+ bool found = false;
+
+ for(struct ifaddrs *ifap = ifa; ifap; ifap = ifap->ifa_next) {
+ if(!ifap->ifa_name) {
+ continue;
+ }
+
+ int index = if_nametoindex(ifap->ifa_name);
+
+ if(mesh->discovery.ifaces[i] == index) {
+ found = true;
+ break;
+ }
+ }
+
+ if(!found) {
+ iface_down(mesh, mesh->discovery.ifaces[i]);
+ } else {
+ i++;
+ }
+ }
-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:
- ;
- }
+ // 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);
+}
-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); }
+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 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 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 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 = 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 = 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 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 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 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 *discovery_loop(void *userdata)
-{
- meshlink_handle_t *mesh = userdata;
+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);
- // asserts
- assert(mesh != NULL);
- assert(mesh->avahi_poll != NULL);
+ scan_ifaddrs(mesh);
- avahi_simple_poll_loop(mesh->avahi_poll);
-
- return NULL;
+ 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);
}
-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);
-
- // 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 *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);
-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;
+ 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;
+
+#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_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);
+ }
+ }
}
projects / meshlink / blobdiff