Fall back to getifaddrs() to get an interface address if there is no default route.

[meshlink] / src / meshlink.c

diff --git a/src/meshlink.c b/src/meshlink.c
index 30b386846a7322e261a1b0f4888331773352fe0c..5b01ad2c1fda7b12abb823baa9c80da391177fb7 100644 (file)
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -37,6 +37,7 @@
 #include "ed25519/sha512.h"
 #include "discovery.h"
 #include "devtools.h"
+#include "graph.h"
 
 #ifndef MSG_NOSIGNAL
 #define MSG_NOSIGNAL 0
@@ -286,6 +287,21 @@ char *meshlink_get_external_address_for_family(meshlink_handle_t *mesh, int fami
        return hostname;
 }
 
+static bool is_localaddr(sockaddr_t *sa) {
+       switch(sa->sa.sa_family) {
+       case AF_INET:
+               return *(uint8_t *)(&sa->in.sin_addr.s_addr) == 127;
+
+       case AF_INET6: {
+               uint16_t first = sa->in6.sin6_addr.s6_addr[0] << 8 | sa->in6.sin6_addr.s6_addr[1];
+               return first == 0 || (first & 0xffc0) == 0xfe80;
+       }
+
+       default:
+               return false;
+       }
+}
+
 char *meshlink_get_local_address_for_family(meshlink_handle_t *mesh, int family) {
        (void)mesh;
 
@@ -299,6 +315,34 @@ char *meshlink_get_local_address_for_family(meshlink_handle_t *mesh, int family)
                success = getlocaladdrname("2606:2800:220:1:248:1893:25c8:1946", localaddr, sizeof(localaddr), mesh->netns);
        }
 
+#ifdef HAVE_GETIFADDRS
+
+       if(!success) {
+               struct ifaddrs *ifa = NULL;
+               getifaddrs(&ifa);
+
+               for(struct ifaddrs *ifap = ifa; ifap; ifap = ifap->ifa_next) {
+                       sockaddr_t *sa = (sockaddr_t *)ifap->ifa_addr;
+
+                       if(sa->sa.sa_family != family) {
+                               continue;
+                       }
+
+                       if(is_localaddr(sa)) {
+                               continue;
+                       }
+
+                       if(!getnameinfo(&sa->sa, SALEN(sa->sa), localaddr, sizeof(localaddr), NULL, 0, NI_NUMERICHOST | NI_NUMERICSERV)) {
+                               success = true;
+                               break;
+                       }
+               }
+
+               freeifaddrs(ifa);
+       }
+
+#endif
+
        if(!success) {
                meshlink_errno = MESHLINK_ENETWORK;
                return NULL;
@@ -667,6 +711,10 @@ static bool finalize_join(meshlink_handle_t *mesh, const void *buf, uint16_t len
                        }
                }
 
+               /* Clear the reachability times, since we ourself have never seen these nodes yet */
+               n->last_reachable = 0;
+               n->last_unreachable = 0;
+
                if(!node_write_config(mesh, n)) {
                        free_node(n);
                        return false;
@@ -719,7 +767,7 @@ static bool invitation_receive(void *handle, uint8_t type, const void *msg, uint
                return finalize_join(mesh, msg, len);
 
        case 1:
-               logger(mesh, MESHLINK_DEBUG, "Invitation succesfully accepted.\n");
+               logger(mesh, MESHLINK_DEBUG, "Invitation successfully accepted.\n");
                shutdown(mesh->sock, SHUT_RDWR);
                mesh->success = true;
                break;
@@ -1527,8 +1575,9 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 
        pthread_cond_wait(&mesh->cond, &mesh->mutex);
        mesh->threadstarted = true;
-       mesh->self->last_reachable = time(NULL);
-       mesh->self->status.dirty = true;
+
+       // Ensure we are considered reachable
+       graph(mesh);
 
        pthread_mutex_unlock(&mesh->mutex);
        return true;
@@ -1543,11 +1592,6 @@ void meshlink_stop(meshlink_handle_t *mesh) {
        pthread_mutex_lock(&mesh->mutex);
        logger(mesh, MESHLINK_DEBUG, "meshlink_stop called\n");
 
-       if(mesh->self) {
-               mesh->self->last_unreachable = time(NULL);
-               mesh->self->status.dirty = true;
-       }
-
        // Shut down the main thread
        event_loop_stop(&mesh->loop);
 
@@ -1587,6 +1631,11 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 
        exit_outgoings(mesh);
 
+       // Ensure we are considered unreachable
+       if(mesh->nodes) {
+               graph(mesh);
+       }
+
        // Try to write out any changed node config files, ignore errors at this point.
        if(mesh->nodes) {
                for splay_each(node_t, n, mesh->nodes) {
@@ -2143,6 +2192,31 @@ meshlink_submesh_t *meshlink_get_node_submesh(meshlink_handle_t *mesh, meshlink_
        return s;
 }
 
+bool meshlink_get_node_reachability(struct meshlink_handle *mesh, struct meshlink_node *node, time_t *last_reachable, time_t *last_unreachable) {
+       if(!mesh || !node) {
+               meshlink_errno = MESHLINK_EINVAL;
+               return NULL;
+       }
+
+       node_t *n = (node_t *)node;
+       bool reachable;
+
+       pthread_mutex_lock(&mesh->mutex);
+       reachable = n->status.reachable && !n->status.blacklisted;
+
+       if(last_reachable) {
+               *last_reachable = n->last_reachable;
+       }
+
+       if(last_unreachable) {
+               *last_unreachable = n->last_unreachable;
+       }
+
+       pthread_mutex_unlock(&mesh->mutex);
+
+       return reachable;
+}
+
 bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *signature, size_t *siglen) {
        if(!mesh || !data || !len || !signature || !siglen) {
                meshlink_errno = MESHLINK_EINVAL;
@@ -2401,7 +2475,7 @@ char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, c
        }
 
        // Ensure no other nodes know about this name
-       if(meshlink_get_node(mesh, name)) {
+       if(lookup_node(mesh, name)) {
                logger(mesh, MESHLINK_ERROR, "A node with name %s is already known!\n", name);
                meshlink_errno = MESHLINK_EEXIST;
                pthread_mutex_unlock(&mesh->mutex);
@@ -2427,7 +2501,7 @@ char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, c
        // If we changed our own host config file, write it out now
        if(mesh->self->status.dirty) {
                if(!node_write_config(mesh, mesh->self)) {
-                       logger(mesh, MESHLINK_ERROR, "Could not write our own host conifg file!\n");
+                       logger(mesh, MESHLINK_ERROR, "Could not write our own host config file!\n");
                        pthread_mutex_unlock(&mesh->mutex);
                        return NULL;
                }
@@ -2892,7 +2966,11 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
                        break;
                }
 
-               if(!config_write(mesh, "current", n->name, &config, mesh->config_key)) {
+               /* Clear the reachability times, since we ourself have never seen these nodes yet */
+               n->last_reachable = 0;
+               n->last_unreachable = 0;
+
+               if(!node_write_config(mesh, n)) {
                        free_node(n);
                        return false;
                }
@@ -2948,6 +3026,10 @@ static bool blacklist(meshlink_handle_t *mesh, node_t *n) {
        n->mtuprobes = 0;
        n->status.udp_confirmed = false;
 
+       if(n->status.reachable) {
+               n->last_unreachable = mesh->loop.now.tv_sec;
+       }
+
        /* Graph updates will suppress status updates for blacklisted nodes, so we need to
         * manually call the status callback if necessary.
         */
@@ -3019,6 +3101,7 @@ static bool whitelist(meshlink_handle_t *mesh, node_t *n) {
        n->status.blacklisted = false;
 
        if(n->status.reachable) {
+               n->last_reachable = mesh->loop.now.tv_sec;
                update_node_status(mesh, n);
        }