X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.c;h=446e8d24a65961777211c5906c4d1f5dc7aa14b3;hb=0a02c50ca8c9d6e66629c0354d56517125411af7;hp=bd74b1d8d358ba93ee6afbbb42c7e1df4b5f9d39;hpb=ac24ceb9a5976628dd4ac31b2b502f1caac2b2ec;p=meshlink diff --git a/src/meshlink.c b/src/meshlink.c index bd74b1d8..446e8d24 100644 --- a/src/meshlink.c +++ b/src/meshlink.c @@ -1,6 +1,6 @@ /* meshlink.c -- Implementation of the MeshLink API. - Copyright (C) 2014 Guus Sliepen + Copyright (C) 2014, 2017 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 @@ -39,6 +39,7 @@ typedef struct { #include "node.h" #include "protocol.h" #include "route.h" +#include "sockaddr.h" #include "utils.h" #include "xalloc.h" #include "ed25519/sha512.h" @@ -180,27 +181,24 @@ static void scan_for_hostname(const char *filename, char **hostname, char **port fclose(f); } -static char *get_my_hostname(meshlink_handle_t* mesh) { - char *hostname = NULL; - char *port = NULL; - char *hostport = NULL; - char *name = mesh->self->name; - char filename[PATH_MAX] = ""; - char line[4096]; - FILE *f; - // Use first Address statement in own host config file - snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name); - scan_for_hostname(filename, &hostname, &port); +static bool is_valid_hostname(const char *hostname) { + for(const char *p = hostname; *p; p++) { + if(!(isalnum(*p) || *p == '-' || *p == '.' || *p == ':')) + return false; + } - if(hostname) - goto done; + return true; +} + +char *meshlink_get_external_address(meshlink_handle_t *mesh) { + char *hostname = NULL; - // If that doesn't work, guess externally visible hostname logger(mesh, MESHLINK_DEBUG, "Trying to discover externally visible hostname...\n"); struct addrinfo *ai = str2addrinfo("meshlink.io", "80", SOCK_STREAM); struct addrinfo *aip = ai; static const char request[] = "GET http://www.meshlink.io/host.cgi HTTP/1.0\r\n\r\n"; + char line[256]; while(aip) { int s = socket(aip->ai_family, aip->ai_socktype, aip->ai_protocol); @@ -233,17 +231,33 @@ static char *get_my_hostname(meshlink_handle_t* mesh) { freeaddrinfo(ai); // Check that the hostname is reasonable - if(hostname) { - for(char *p = hostname; *p; p++) { - if(isalnum(*p) || *p == '-' || *p == '.' || *p == ':') - continue; - // If not, forget it. - free(hostname); - hostname = NULL; - break; - } + if(hostname && !is_valid_hostname(hostname)) { + free(hostname); + hostname = NULL; } + if(!hostname) + meshlink_errno = MESHLINK_ERESOLV; + + return hostname; +} + +static char *get_my_hostname(meshlink_handle_t* mesh) { + char *hostname = NULL; + char *port = NULL; + char *hostport = NULL; + char *name = mesh->self->name; + char filename[PATH_MAX] = ""; + FILE *f; + + // Use first Address statement in own host config file + snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name); + scan_for_hostname(filename, &hostname, &port); + + if(hostname) + goto done; + + hostname = meshlink_get_external_address(mesh); if(!hostname) return NULL; @@ -660,7 +674,7 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) { 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; @@ -699,6 +713,78 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) { 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)); @@ -744,11 +830,6 @@ static bool meshlink_setup(meshlink_handle_t *mesh) { } 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; @@ -785,7 +866,7 @@ meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *nam 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; @@ -845,6 +926,10 @@ meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *nam return NULL; } + add_local_addresses(mesh); + + idle_set(&mesh->loop, idle, mesh); + logger(NULL, MESHLINK_DEBUG, "meshlink_open returning\n"); return mesh; } @@ -869,10 +954,23 @@ bool meshlink_start(meshlink_handle_t *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 @@ -887,6 +985,8 @@ bool meshlink_start(meshlink_handle_t *mesh) { // 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); @@ -915,10 +1015,16 @@ void meshlink_stop(meshlink_handle_t *mesh) { // 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)); @@ -927,16 +1033,6 @@ void meshlink_stop(meshlink_handle_t *mesh) { 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)); } @@ -946,6 +1042,9 @@ void meshlink_close(meshlink_handle_t *mesh) { 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)); @@ -975,6 +1074,49 @@ void meshlink_close(meshlink_handle_t *mesh) { 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; @@ -1039,8 +1181,10 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const 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); @@ -1114,6 +1258,15 @@ char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node) { 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; @@ -1279,7 +1432,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) { } // 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)); @@ -1295,7 +1448,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) { 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; @@ -1323,22 +1476,99 @@ bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) { meshlink_errno = MESHLINK_EINVAL; return false; } - + + if(!is_valid_hostname(address)) { + logger(mesh, MESHLINK_DEBUG, "Invalid character in address: %s\n", address); + meshlink_errno = MESHLINK_EINVAL; + return false; + } + bool rval = false; pthread_mutex_lock(&(mesh->mesh_mutex)); + rval = append_config_file(mesh, mesh->self->name, "Address", address); + pthread_mutex_unlock(&(mesh->mesh_mutex)); - for(const char *p = address; *p; p++) { - if(isalnum(*p) || *p == '-' || *p == '.' || *p == ':') - continue; - logger(mesh, MESHLINK_DEBUG, "Invalid character in address: %s\n", address); + return rval; +} + +bool meshlink_add_external_address(meshlink_handle_t *mesh) { + if(!mesh) { meshlink_errno = MESHLINK_EINVAL; - pthread_mutex_unlock(&(mesh->mesh_mutex)); return false; } + char *address = meshlink_get_external_address(mesh); + if(!address) + return false; + + bool rval = false; + + pthread_mutex_lock(&(mesh->mesh_mutex)); rval = append_config_file(mesh, mesh->self->name, "Address", address); pthread_mutex_unlock(&(mesh->mesh_mutex)); + + free(address); + return rval; +} + +int meshlink_get_port(meshlink_handle_t *mesh) { + if(!mesh) { + meshlink_errno = MESHLINK_EINVAL; + return -1; + } + + if(!mesh->myport) { + meshlink_errno = MESHLINK_EINTERNAL; + return -1; + } + + return atoi(mesh->myport); +} + +bool meshlink_set_port(meshlink_handle_t *mesh, int port) { + if(!mesh || port < 0 || port >= 65536 || mesh->threadstarted) { + meshlink_errno = MESHLINK_EINVAL; + return false; + } + + if(mesh->myport && port == atoi(mesh->myport)) + return true; + + if(!try_bind(port)) { + meshlink_errno = MESHLINK_ENETWORK; + return false; + } + + bool rval = false; + + pthread_mutex_lock(&(mesh->mesh_mutex)); + if(mesh->threadstarted) { + meshlink_errno = MESHLINK_EINVAL; + goto done; + } + + close_network_connections(mesh); + exit_configuration(&mesh->config); + + char portstr[10]; + snprintf(portstr, sizeof portstr, "%d", port); + portstr[sizeof portstr - 1] = 0; + + modify_config_file(mesh, mesh->name, "Port", portstr, true); + + init_configuration(&mesh->config); + + if(!read_server_config(mesh)) + meshlink_errno = MESHLINK_ESTORAGE; + else if(!setup_network(mesh)) + meshlink_errno = MESHLINK_ENETWORK; + else + rval = true; + +done: + pthread_mutex_unlock(&(mesh->mesh_mutex)); + return rval; } @@ -1809,12 +2039,20 @@ void meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) { 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)); @@ -1894,7 +2132,6 @@ meshlink_edge_t **meshlink_get_all_edges_state(meshlink_handle_t *mesh, meshlink *nmemb = result_size; } else { *nmemb = 0; - free(result); meshlink_errno = MESHLINK_ENOMEM; } @@ -1948,6 +2185,11 @@ static ssize_t channel_send(struct utcp *utcp, const void *data, size_t len) { } 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; } @@ -1961,7 +2203,27 @@ static void channel_receive(meshlink_handle_t *mesh, meshlink_node_t *source, co utcp_recv(n->utcp, data, len); } +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; @@ -1974,10 +2236,12 @@ void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_ac pthread_mutex_unlock(&mesh->mesh_mutex); } -void meshlink_channel_init(meshlink_handle_t *mesh) { -} - 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) { @@ -2001,20 +2265,50 @@ meshlink_channel_t *meshlink_channel_open(meshlink_handle_t *mesh, meshlink_node } 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) {