+/*
+ 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__) || defined(__unix) && !defined(__linux)
+#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>
#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,
struct cmsghdr align;
} u;
+ memset(&u, 0, sizeof(u));
+
struct msghdr msg = {
.msg_name = (struct sockaddr *) &dest->sa,
.msg_namelen = SALEN(dest->sa),
.msg_controllen = sizeof(u.buf),
};
-
struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_level = IPPROTO_IP;
cmsg->cmsg_type = IP_PKTINFO;
// 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
// 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
static void send_mdns_packet(meshlink_handle_t *mesh, const discovery_address_t *addr) {
// Configure the socket to send the packet to the right interface
int fd;
- uint8_t data[1024];
+ uint8_t request[1024], response[1024];
char *fingerprint = meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self);
const char *keys[] = {MESHLINK_MDNS_NAME_KEY, MESHLINK_MDNS_FINGERPRINT_KEY};
const char *values[] = {mesh->name, fingerprint};
- size_t size = prepare_packet(data, sizeof data, fingerprint, mesh->appname, "tcp", atoi(mesh->myport), 2, keys, values, false);
+ size_t request_size = prepare_request(request, sizeof request, mesh->appname, "tcp");
+ size_t response_size = prepare_response(response, sizeof response, fingerprint, mesh->appname, "tcp", atoi(mesh->myport), 2, keys, values);
free(fingerprint);
switch(addr->address.sa.sa_family) {
#endif
- send_mdns_packet_ipv4(mesh, fd, addr->index, &addr->address, &mdns_address_ipv4, data, size);
+ send_mdns_packet_ipv4(mesh, fd, addr->index, &addr->address, &mdns_address_ipv4, request, request_size);
+ send_mdns_packet_ipv4(mesh, fd, addr->index, &addr->address, &mdns_address_ipv4, response, response_size);
break;
case AF_INET6:
#endif
- send_mdns_packet_ipv6(mesh, fd, addr->index, &addr->address, &mdns_address_ipv6, data, size);
+ send_mdns_packet_ipv6(mesh, fd, addr->index, &addr->address, &mdns_address_ipv6, request, request_size);
+ send_mdns_packet_ipv6(mesh, fd, addr->index, &addr->address, &mdns_address_ipv6, response, response_size);
break;
default:
uint16_t port = 0;
const char *keys[2] = {MESHLINK_MDNS_NAME_KEY, MESHLINK_MDNS_FINGERPRINT_KEY};
char *values[2] = {NULL, NULL};
- bool response;
- if(parse_packet(buf, len, &name, mesh->appname, "tcp", &port, 2, keys, values, &response)) {
+ 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) {
logger(mesh, MESHLINK_INFO, "Node %s discovered on the local network.\n", n->name);
}
- if(!response && n != mesh->self) {
- // Send a unicast response back
- char *fingerprint = meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self);
- const char *response_values[] = {mesh->name, fingerprint};
- size_t size = prepare_packet(buf, sizeof(buf), fingerprint, mesh->appname, "tcp", atoi(mesh->myport), 2, keys, response_values, true);
- sendto(io->fd, buf, size, MSG_DONTWAIT | MSG_NOSIGNAL, &sa.sa, sl);
- free(fingerprint);
- }
-
switch(sa.sa.sa_family) {
case AF_INET:
- sa.in.sin_port = port;
+ sa.in.sin_port = htons(port);
break;
case AF_INET6:
- sa.in6.sin6_port = port;
+ sa.in6.sin6_port = htons(port);
break;
default:
if(sa.sa.sa_family != AF_UNKNOWN) {
n->catta_address = sa;
+ n->last_connect_try = 0;
node_add_recent_address(mesh, n, &sa);
- connection_t *c = n->connection;
+ if(n->connection) {
+ n->connection->last_ping_time = -3600;
+ }
+
+ for list_each(outgoing_t, outgoing, mesh->outgoings) {
+ if(outgoing->node != n) {
+ continue;
+ }
- if(c && c->outgoing && !c->status.active) {
- c->outgoing->timeout = 0;
+ outgoing->timeout = 0;
- if(c->outgoing->ev.cb) {
- timeout_set(&mesh->loop, &c->outgoing->ev, &(struct timespec) {
+ if(outgoing->ev.cb) {
+ timeout_set(&mesh->loop, &outgoing->ev, &(struct timespec) {
0, 0
});
}
-
- c->last_ping_time = -3600;
}
}
}
+ } else if(parse_request(buf, len, mesh->appname, "tcp")) {
+ // Send a unicast response back
+ 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);
+ sendto(io->fd, buf, size, MSG_DONTWAIT | MSG_NOSIGNAL, &sa.sa, sl);
+ free(fingerprint);
}
free(name);
handle_network_change(mesh, true);
}
-static void iface_down(meshlink_handle_t *const mesh, int index) {
+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) {
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++;
+ }
+ }
+
+ // 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 {
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 = 5353;
+ 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 = 5353;
+ addr.address.in6.sin6_port = ntohs(5353);
addr.address.in6.sin6_scope_id = ifa->ifa_index;
} else {
addr.address.sa.sa_family = AF_UNKNOWN;
static void netlink_io_handler(event_loop_t *loop, void *data, int flags) {
(void)flags;
(void)data;
- static time_t prev_update;
meshlink_handle_t *mesh = loop->data;
struct {
} else {
netlink_parse(mesh, &msg, result);
- if(loop->now.tv_sec > prev_update + 5) {
- prev_update = loop->now.tv_sec;
- handle_network_change(mesh, 1);
+ 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;
- static time_t prev_update;
meshlink_handle_t *mesh = loop->data;
struct {
switch(msg.rtm.rtm_type) {
case RTM_IFINFO:
+ pfroute_parse_iface(mesh, &msg.rtm);
+ break;
+
case RTM_NEWADDR:
case RTM_DELADDR:
- if(loop->now.tv_sec > prev_update + 5) {
- prev_update = loop->now.tv_sec;
- handle_network_change(mesh, 1);
- }
-
+ pfroute_parse_addr(mesh, &msg.rtm);
break;
default:
// 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));
+ }
+
sockaddr_t sa4 = {
.in.sin_family = AF_INET,
.in.sin_port = ntohs(5353),
};
setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
- bind(fd, &sa4.sa, SALEN(sa4.sa));
- setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one, sizeof(one));
- setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl));
- io_add(&mesh->loop, &mesh->discovery.sockets[0], mdns_io_handler, &mesh->discovery.sockets[0], fd, IO_READ);
+#ifdef SO_REUSEPORT
+ setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &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);
+ }
sockaddr_t sa6 = {
.in6.sin6_family = AF_INET6,
.in6.sin6_port = ntohs(5353),
};
fd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
+
+ if(fd == -1) {
+ logger(mesh, MESHLINK_ERROR, "Error creating IPv6 socket: %s", strerror(errno));
+ }
+
setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
+#ifdef SO_REUSEPORT
+ setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one));
+#endif
setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
- bind(fd, &sa6.sa, SALEN(sa6.sa));
setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &one, sizeof(one));
setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl));
- io_add(&mesh->loop, &mesh->discovery.sockets[1], mdns_io_handler, &mesh->discovery.sockets[1], fd, IO_READ);
+ 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 IPv4 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);
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);
logger(mesh, MESHLINK_WARNING, "Could not open PF_ROUTE socket: %s", strerror(errno));
}
+ scan_ifaddrs(mesh);
#endif
return true;
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);