/*
meshlink.c -- Implementation of the MeshLink API.
- Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
+ Copyright (C) 2014, 2017 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
#include "node.h"
#include "protocol.h"
#include "route.h"
+#include "sockaddr.h"
#include "utils.h"
#include "xalloc.h"
#include "ed25519/sha512.h"
logger(mesh, MESHLINK_DEBUG, "Done.\n");
snprintf(privname, sizeof privname, "%s" SLASH "ecdsa_key.priv", mesh->confbase);
- f = fopen(privname, "w");
+ f = fopen(privname, "wb");
if(!f) {
meshlink_errno = MESHLINK_ESTORAGE;
return true;
}
+static struct timeval idle(event_loop_t *loop, void *data) {
+ meshlink_handle_t *mesh = data;
+ struct timeval t, tmin = {3600, 0};
+ for splay_each(node_t, n, mesh->nodes) {
+ if(!n->utcp)
+ continue;
+ t = utcp_timeout(n->utcp);
+ if(timercmp(&t, &tmin, <))
+ tmin = t;
+ }
+ return tmin;
+}
+
+// Find out what local address a socket would use if we connect to the given address.
+// We do this using connect() on a UDP socket, so the kernel has to resolve the address
+// of both endpoints, but this will actually not send any UDP packet.
+static bool getlocaladdrname(char *destaddr, char *host, socklen_t hostlen) {
+ struct addrinfo *rai = NULL;
+ const struct addrinfo hint = {
+ .ai_family = AF_UNSPEC,
+ .ai_socktype = SOCK_DGRAM,
+ .ai_protocol = IPPROTO_UDP,
+ };
+
+ if(getaddrinfo(destaddr, "80", &hint, &rai) || !rai)
+ return false;
+
+ int sock = socket(rai->ai_family, rai->ai_socktype, rai->ai_protocol);
+ if(sock == -1) {
+ freeaddrinfo(rai);
+ return false;
+ }
+
+ if(connect(sock, rai->ai_addr, rai->ai_addrlen) && !sockwouldblock(errno)) {
+ freeaddrinfo(rai);
+ return false;
+ }
+
+ freeaddrinfo(rai);
+
+ struct sockaddr_storage sn;
+ socklen_t sl = sizeof sn;
+
+ if(getsockname(sock, (struct sockaddr *)&sn, &sl))
+ return false;
+
+ if(getnameinfo((struct sockaddr *)&sn, sl, host, hostlen, NULL, 0, NI_NUMERICHOST | NI_NUMERICSERV))
+ return false;
+
+ return true;
+}
+
+// Get our local address(es) by simulating connecting to an Internet host.
+static void add_local_addresses(meshlink_handle_t *mesh) {
+ char host[NI_MAXHOST];
+ char entry[MAX_STRING_SIZE];
+
+ // IPv4 example.org
+
+ if(getlocaladdrname("93.184.216.34", host, sizeof host)) {
+ snprintf(entry, sizeof entry, "%s %s", host, mesh->myport);
+ append_config_file(mesh, mesh->name, "Address", entry);
+ }
+
+ // IPv6 example.org
+
+ if(getlocaladdrname("2606:2800:220:1:248:1893:25c8:1946", host, sizeof host)) {
+ snprintf(entry, sizeof entry, "%s %s", host, mesh->myport);
+ append_config_file(mesh, mesh->name, "Address", entry);
+ }
+}
+
static bool meshlink_setup(meshlink_handle_t *mesh) {
if(mkdir(mesh->confbase, 0777) && errno != EEXIST) {
logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", mesh->confbase, strerror(errno));
}
meshlink_handle_t *meshlink_open(const char *confbase, const char *name, const char* appname, dev_class_t devclass) {
- return meshlink_open_with_size(confbase, name, appname, devclass, sizeof(meshlink_handle_t));
-}
-
-meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *name, const char* appname, dev_class_t devclass, size_t size) {
-
// Validate arguments provided by the application
bool usingname = false;
return NULL;
}
- meshlink_handle_t *mesh = xzalloc(size);
+ meshlink_handle_t *mesh = xzalloc(sizeof(meshlink_handle_t));
mesh->confbase = xstrdup(confbase);
mesh->appname = xstrdup(appname);
mesh->devclass = devclass;
return NULL;
}
+ add_local_addresses(mesh);
+
+ idle_set(&mesh->loop, idle, mesh);
+
logger(NULL, MESHLINK_DEBUG, "meshlink_open returning\n");
return mesh;
}
meshlink_errno = MESHLINK_EINVAL;
return false;
}
- pthread_mutex_lock(&(mesh->mesh_mutex));
logger(mesh, MESHLINK_DEBUG, "meshlink_start called\n");
+ pthread_mutex_lock(&(mesh->mesh_mutex));
+
+ if(mesh->threadstarted) {
+ logger(mesh, MESHLINK_DEBUG, "thread was already running\n");
+ pthread_mutex_unlock(&(mesh->mesh_mutex));
+ return true;
+ }
+
+ if(mesh->listen_socket[0].tcp.fd < 0) {
+ logger(mesh, MESHLINK_ERROR, "Listening socket not open\n");
+ meshlink_errno = MESHLINK_ENETWORK;
+ return false;
+ }
+
mesh->thedatalen = 0;
// TODO: open listening sockets first
// Start the main thread
+ event_loop_start(&mesh->loop);
+
if(pthread_create(&mesh->thread, NULL, meshlink_main_loop, mesh) != 0) {
logger(mesh, MESHLINK_DEBUG, "Could not start thread: %s\n", strerror(errno));
memset(&mesh->thread, 0, sizeof mesh->thread);
// Stop discovery
discovery_stop(mesh);
- // Shut down a listening socket to signal the main thread to shut down
+ pthread_mutex_lock(&(mesh->mesh_mutex));
+ logger(mesh, MESHLINK_DEBUG, "meshlink_stop called\n");
+
+ // Shut down the main thread
+ event_loop_stop(&mesh->loop);
+ // Send ourselves a UDP packet to kick the event loop
listen_socket_t *s = &mesh->listen_socket[0];
- shutdown(s->tcp.fd, SHUT_RDWR);
+ if(sendto(s->udp.fd, "", 1, MSG_NOSIGNAL, &s->sa.sa, SALEN(s->sa.sa)) == -1)
+ logger(mesh, MESHLINK_ERROR, "Could not send a UDP packet to ourself");
// Wait for the main thread to finish
pthread_mutex_unlock(&(mesh->mesh_mutex));
mesh->threadstarted = false;
- // Fix the socket
-
- closesocket(s->tcp.fd);
- io_del(&mesh->loop, &s->tcp);
- s->tcp.fd = setup_listen_socket(&s->sa);
- if(s->tcp.fd < 0)
- logger(mesh, MESHLINK_ERROR, "Could not repair listenen socket!");
- else
- io_add(&mesh->loop, &s->tcp, handle_new_meta_connection, s, s->tcp.fd, IO_READ);
-
pthread_mutex_unlock(&(mesh->mesh_mutex));
}
return;
}
+ // stop can be called even if mesh has not been started
+ meshlink_stop(mesh);
+
// lock is not released after this
pthread_mutex_lock(&(mesh->mesh_mutex));
free(mesh);
}
+static void deltree(const char *dirname) {
+ DIR *d = opendir(dirname);
+ if(d) {
+ struct dirent *ent;
+ while((ent = readdir(d))) {
+ if(ent->d_name[0] == '.')
+ continue;
+ char filename[PATH_MAX];
+ snprintf(filename, sizeof filename, "%s" SLASH "%s", dirname, ent->d_name);
+ if(unlink(filename))
+ deltree(filename);
+ }
+ closedir(d);
+ }
+ rmdir(dirname);
+ return;
+}
+
+bool meshlink_destroy(const char *confbase) {
+ if(!confbase) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return false;
+ }
+
+ char filename[PATH_MAX];
+ snprintf(filename, sizeof filename, "%s" SLASH "meshlink.conf", confbase);
+
+ if(unlink(filename)) {
+ if(errno == ENOENT) {
+ meshlink_errno = MESHLINK_ENOENT;
+ return false;
+ } else {
+ logger(NULL, MESHLINK_ERROR, "Cannot delete %s: %s\n", filename, strerror(errno));
+ meshlink_errno = MESHLINK_ESTORAGE;
+ return false;
+ }
+ }
+
+ deltree(confbase);
+
+ return true;
+}
+
void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb) {
if(!mesh) {
meshlink_errno = MESHLINK_EINVAL;
hdr = (meshlink_packethdr_t *)packet->data;
memset(hdr, 0, sizeof *hdr);
- memcpy(hdr->destination, destination->name, sizeof hdr->destination);
- memcpy(hdr->source, mesh->self->name, sizeof hdr->source);
+ // leave the last byte as 0 to make sure strings are always
+ // null-terminated if they are longer than the buffer
+ strncpy(hdr->destination, destination->name, (sizeof hdr->destination) - 1);
+ strncpy(hdr->source, mesh->self->name, (sizeof hdr->source) -1 );
memcpy(packet->data + sizeof *hdr, data, len);
return fingerprint;
}
+meshlink_node_t *meshlink_get_self(meshlink_handle_t *mesh) {
+ if(!mesh) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return NULL;
+ }
+
+ return (meshlink_node_t *)mesh->self;
+}
+
meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name) {
if(!mesh || !name) {
meshlink_errno = MESHLINK_EINVAL;
}
// Create a new key if necessary.
- FILE *f = fopen(filename, "r");
+ FILE *f = fopen(filename, "rb");
if(!f) {
if(errno != ENOENT) {
logger(mesh, MESHLINK_DEBUG, "Could not read %s: %s\n", filename, strerror(errno));
pthread_mutex_unlock(&(mesh->mesh_mutex));
return false;
}
- f = fopen(filename, "w");
+ f = fopen(filename, "wb");
if(!f) {
logger(mesh, MESHLINK_DEBUG, "Could not write %s: %s\n", filename, strerror(errno));
meshlink_errno = MESHLINK_ESTORAGE;
return;
}
+void meshlink_set_default_blacklist(meshlink_handle_t *mesh, bool blacklist) {
+ mesh->default_blacklist = blacklist;
+}
+
/* Hint that a hostname may be found at an address
* See header file for detailed comment.
*/
void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, const struct sockaddr *addr) {
if(!mesh || !node || !addr)
return;
+
+ // Ignore hints about ourself.
+ if((node_t *)node == mesh->self)
+ return;
pthread_mutex_lock(&(mesh->mesh_mutex));
*nmemb = result_size;
} else {
*nmemb = 0;
- free(result);
meshlink_errno = MESHLINK_ENOMEM;
}
return meshlink_send(mesh, (meshlink_node_t *)n, data, len) ? len : -1;
}
-void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_accept_cb_t cb) {
- mesh->channel_accept_cb = cb;
-}
-
void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_receive_cb_t cb) {
+ if(!mesh || !channel) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return;
+ }
+
channel->receive_cb = cb;
}
utcp_recv(n->utcp, data, len);
}
-void meshlink_channel_init(meshlink_handle_t *mesh) {
+static void channel_poll(struct utcp_connection *connection, size_t len) {
+ meshlink_channel_t *channel = connection->priv;
+ if(!channel)
+ abort();
+ node_t *n = channel->node;
+ meshlink_handle_t *mesh = n->mesh;
+ if(channel->poll_cb)
+ channel->poll_cb(mesh, channel, len);
+}
+
+void meshlink_set_channel_poll_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_poll_cb_t cb) {
+ channel->poll_cb = cb;
+ utcp_set_poll_cb(channel->c, cb ? channel_poll : NULL);
+}
+
+void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_accept_cb_t cb) {
+ if(!mesh) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return;
+ }
+
+ pthread_mutex_lock(&mesh->mesh_mutex);
+ mesh->channel_accept_cb = cb;
+ mesh->receive_cb = channel_receive;
+ for splay_each(node_t, n, mesh->nodes) {
+ if(!n->utcp && n != mesh->self) {
+ logger(mesh, MESHLINK_WARNING, "utcp_init on node %s", n->name);
+ n->utcp = utcp_init(channel_accept, channel_pre_accept, channel_send, n);
+ }
+ }
+ pthread_mutex_unlock(&mesh->mesh_mutex);
}
meshlink_channel_t *meshlink_channel_open(meshlink_handle_t *mesh, meshlink_node_t *node, uint16_t port, meshlink_channel_receive_cb_t cb, const void *data, size_t len) {
+ if(!mesh || !node) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return NULL;
+ }
+
logger(mesh, MESHLINK_WARNING, "meshlink_channel_open(%p, %s, %u, %p, %p, %zu)\n", mesh, node->name, port, cb, data, len);
node_t *n = (node_t *)node;
if(!n->utcp) {
}
void meshlink_channel_shutdown(meshlink_handle_t *mesh, meshlink_channel_t *channel, int direction) {
+ if(!mesh || !channel) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return;
+ }
+
utcp_shutdown(channel->c, direction);
}
void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t *channel) {
+ if(!mesh || !channel) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return;
+ }
+
utcp_close(channel->c);
free(channel);
}
ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len) {
- // TODO: locking.
+ if(!mesh || !channel) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return -1;
+ }
+
+ if(!len)
+ return 0;
+
+ if(!data) {
+ meshlink_errno = MESHLINK_EINVAL;
+ return -1;
+ }
+
+ // TODO: more finegrained locking.
// Ideally we want to put the data into the UTCP connection's send buffer.
// Then, preferrably only if there is room in the receiver window,
// kick the meshlink thread to go send packets.
- return utcp_send(channel->c, data, len);
+
+ pthread_mutex_lock(&mesh->mesh_mutex);
+ ssize_t retval = utcp_send(channel->c, data, len);
+ pthread_mutex_unlock(&mesh->mesh_mutex);
+
+ if(retval < 0)
+ meshlink_errno = MESHLINK_ENETWORK;
+ return retval;
+}
+
+void update_node_status(meshlink_handle_t *mesh, node_t *n) {
+ if(n->status.reachable && mesh->channel_accept_cb && !n->utcp)
+ n->utcp = utcp_init(channel_accept, channel_pre_accept, channel_send, n);
+ if(mesh->node_status_cb)
+ mesh->node_status_cb(mesh, (meshlink_node_t *)n, n->status.reachable);
}
static void __attribute__((constructor)) meshlink_init(void) {
crypto_exit();
}
-
/// Device class traits
dev_class_traits_t dev_class_traits[_DEV_CLASS_MAX +1] = {
{ .min_connects = 3, .max_connects = 10000, .edge_weight = 1 }, // DEV_CLASS_BACKBONE