/*
net_socket.c -- Handle various kinds of sockets.
- Copyright (C) 1998-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
- 2000-2002 Guus Sliepen <guus@sliepen.warande.net>
+ 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
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., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id: net_socket.c,v 1.1.2.7 2002/03/01 14:09:31 guus Exp $
+ 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.
*/
-#include "config.h"
-
-#include <errno.h>
-#include <fcntl.h>
-#include <netdb.h>
-#include <netinet/in.h>
-#ifdef HAVE_LINUX
- #include <netinet/ip.h>
- #include <netinet/tcp.h>
-#endif
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <signal.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <syslog.h>
-#include <unistd.h>
-#include <sys/ioctl.h>
-/* SunOS really wants sys/socket.h BEFORE net/if.h,
- and FreeBSD wants these lines below the rest. */
-#include <arpa/inet.h>
-#include <sys/socket.h>
-#include <net/if.h>
-
-#include <utils.h>
-#include <xalloc.h>
-#include <avl_tree.h>
-#include <list.h>
+#include "system.h"
#include "conf.h"
#include "connection.h"
+#include "list.h"
+#include "logger.h"
+#include "meshlink_internal.h"
#include "meta.h"
#include "net.h"
#include "netutl.h"
-#include "process.h"
#include "protocol.h"
-#include "subnet.h"
-#include "graph.h"
-#include "process.h"
-#include "route.h"
-#include "device.h"
-#include "event.h"
+#include "utils.h"
+#include "xalloc.h"
-#include "system.h"
+/* Needed on Mac OS/X */
+#ifndef SOL_TCP
+#define SOL_TCP IPPROTO_TCP
+#endif
-int addressfamily = AF_INET;
-int maxtimeout = 900;
-int seconds_till_retry = 5;
+#ifndef MSG_NOSIGNAL
+#define MSG_NOSIGNAL 0
+#endif
-int tcp_socket[MAXSOCKETS];
-int udp_socket[MAXSOCKETS];
-int listen_sockets = 0;
+static const int max_connection_burst = 100;
/* Setup sockets */
-int setup_listen_socket(sockaddr_t *sa)
-{
- int nfd, flags;
- char *addrstr;
- int option;
-#ifdef HAVE_LINUX
- char *interface;
- struct ifreq ifr;
+static void configure_tcp(connection_t *c) {
+#ifdef O_NONBLOCK
+ int flags = fcntl(c->socket, F_GETFL);
+
+ if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0) {
+ logger(c->mesh, MESHLINK_ERROR, "System call `%s' failed: %s", "fcntl", strerror(errno));
+ }
+
+#elif defined(WIN32)
+ unsigned long arg = 1;
+
+ if(ioctlsocket(c->socket, FIONBIO, &arg) != 0) {
+ logger(c->mesh, MESHLINK_ERROR, "System call `%s' failed: %s", "ioctlsocket", sockstrerror(sockerrno));
+ }
+
#endif
-cp
- if((nfd = socket(sa->sa.sa_family, SOCK_STREAM, IPPROTO_TCP)) < 0)
- {
- syslog(LOG_ERR, _("Creating metasocket failed: %s"), strerror(errno));
- return -1;
- }
-
- flags = fcntl(nfd, F_GETFL);
- if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0)
- {
- close(nfd);
- syslog(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
- return -1;
- }
-
- /* Optimize TCP settings */
-
- option = 1;
- setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
-#ifdef HAVE_LINUX
- setsockopt(nfd, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
-
- option = IPTOS_LOWDELAY;
- setsockopt(nfd, SOL_IP, IP_TOS, &option, sizeof(option));
-
- if(get_config_string(lookup_config(config_tree, "BindToInterface"), &interface))
- {
- memset(&ifr, 0, sizeof(ifr));
- strncpy(ifr.ifr_ifrn.ifrn_name, interface, IFNAMSIZ);
- if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)))
- {
- close(nfd);
- syslog(LOG_ERR, _("Can't bind to interface %s: %s"), interface, strerror(errno));
- return -1;
+
+#if defined(SOL_TCP) && defined(TCP_NODELAY)
+ int nodelay = 1;
+ setsockopt(c->socket, SOL_TCP, TCP_NODELAY, (void *)&nodelay, sizeof(nodelay));
+#endif
+
+#if defined(IP_TOS) && defined(IPTOS_LOWDELAY)
+ int lowdelay = IPTOS_LOWDELAY;
+ setsockopt(c->socket, IPPROTO_IP, IP_TOS, (void *)&lowdelay, sizeof(lowdelay));
+#endif
+}
+
+static bool bind_to_address(meshlink_handle_t *mesh, connection_t *c) {
+ int s = -1;
+
+ for(int i = 0; i < mesh->listen_sockets && mesh->listen_socket[i].bindto; i++) {
+ if(mesh->listen_socket[i].sa.sa.sa_family != c->address.sa.sa_family) {
+ continue;
+ }
+
+ if(s >= 0) {
+ return false;
+ }
+
+ s = i;
+ }
+
+ if(s < 0) {
+ return false;
+ }
+
+ sockaddr_t sa = mesh->listen_socket[s].sa;
+
+ if(sa.sa.sa_family == AF_INET) {
+ sa.in.sin_port = 0;
+ } else if(sa.sa.sa_family == AF_INET6) {
+ sa.in6.sin6_port = 0;
}
- }
+
+ if(bind(c->socket, &sa.sa, SALEN(sa.sa))) {
+ logger(mesh, MESHLINK_WARNING, "Can't bind outgoing socket: %s", strerror(errno));
+ return false;
+ }
+
+ return true;
+}
+
+int setup_listen_socket(const sockaddr_t *sa) {
+ int nfd;
+ char *addrstr;
+ int option;
+
+ nfd = socket(sa->sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
+
+ if(nfd < 0) {
+ logger(NULL, MESHLINK_ERROR, "Creating metasocket failed: %s", sockstrerror(sockerrno));
+ return -1;
+ }
+
+#ifdef FD_CLOEXEC
+ fcntl(nfd, F_SETFD, FD_CLOEXEC);
#endif
- if(bind(nfd, &sa->sa, SALEN(sa->sa)))
- {
- close(nfd);
- addrstr = sockaddr2hostname(sa);
- syslog(LOG_ERR, _("Can't bind to %s/tcp: %s"), addrstr, strerror(errno));
- free(addrstr);
- return -1;
- }
-
- if(listen(nfd, 3))
- {
- close(nfd);
- syslog(LOG_ERR, _("System call `%s' failed: %s"), "listen", strerror(errno));
- return -1;
- }
-cp
- return nfd;
+ /* Optimize TCP settings */
+
+ option = 1;
+ setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof(option));
+
+#if defined(IPV6_V6ONLY)
+
+ if(sa->sa.sa_family == AF_INET6) {
+ setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof(option));
+ }
+
+#else
+#warning IPV6_V6ONLY not defined
+#endif
+
+ if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
+ closesocket(nfd);
+ addrstr = sockaddr2hostname(sa);
+ logger(NULL, MESHLINK_ERROR, "Can't bind to %s/tcp: %s", addrstr, sockstrerror(sockerrno));
+ free(addrstr);
+ return -1;
+ }
+
+ if(listen(nfd, 3)) {
+ closesocket(nfd);
+ logger(NULL, MESHLINK_ERROR, "System call `%s' failed: %s", "listen", sockstrerror(sockerrno));
+ return -1;
+ }
+
+ return nfd;
}
-int setup_vpn_in_socket(sockaddr_t *sa)
-{
- int nfd, flags;
- char *addrstr;
- int option;
-#ifdef HAVE_LINUX
- char *interface;
- struct ifreq ifr;
+int setup_vpn_in_socket(meshlink_handle_t *mesh, const sockaddr_t *sa) {
+ int nfd;
+ char *addrstr;
+ int option;
+
+ nfd = socket(sa->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP);
+
+ if(nfd < 0) {
+ logger(mesh, MESHLINK_ERROR, "Creating UDP socket failed: %s", sockstrerror(sockerrno));
+ return -1;
+ }
+
+#ifdef FD_CLOEXEC
+ fcntl(nfd, F_SETFD, FD_CLOEXEC);
#endif
-cp
- if((nfd = socket(sa->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP)) < 0)
- {
- syslog(LOG_ERR, _("Creating UDP socket failed: %s"), strerror(errno));
- return -1;
- }
-
- flags = fcntl(nfd, F_GETFL);
- if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0)
- {
- close(nfd);
- syslog(LOG_ERR, _("System call `%s' failed: %s"), "fcntl", strerror(errno));
- return -1;
- }
-
- option = 1;
- setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
-#ifdef HAVE_LINUX
- if(get_config_string(lookup_config(config_tree, "BindToInterface"), &interface))
- {
- memset(&ifr, 0, sizeof(ifr));
- strncpy(ifr.ifr_ifrn.ifrn_name, interface, IFNAMSIZ);
- if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)))
+
+#ifdef O_NONBLOCK
{
- close(nfd);
- syslog(LOG_ERR, _("Can't bind to interface %s: %s"), interface, strerror(errno));
- return -1;
+ int flags = fcntl(nfd, F_GETFL);
+
+ if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
+ closesocket(nfd);
+ logger(mesh, MESHLINK_ERROR, "System call `%s' failed: %s", "fcntl",
+ strerror(errno));
+ return -1;
+ }
}
- }
+#elif defined(WIN32)
+ {
+ unsigned long arg = 1;
+
+ if(ioctlsocket(nfd, FIONBIO, &arg) != 0) {
+ closesocket(nfd);
+ logger(mesh, MESHLINK_ERROR, "Call to `%s' failed: %s", "ioctlsocket", sockstrerror(sockerrno));
+ return -1;
+ }
+ }
+#endif
+
+ option = 1;
+ setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof(option));
+ setsockopt(nfd, SOL_SOCKET, SO_BROADCAST, (void *)&option, sizeof(option));
+
+#if defined(IPV6_V6ONLY)
+
+ if(sa->sa.sa_family == AF_INET6) {
+ setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof(option));
+ }
+
+#endif
+
+#if defined(IP_DONTFRAG) && !defined(IP_DONTFRAGMENT)
+#define IP_DONTFRAGMENT IP_DONTFRAG
#endif
- if(bind(nfd, &sa->sa, SALEN(sa->sa)))
- {
- close(nfd);
- addrstr = sockaddr2hostname(sa);
- syslog(LOG_ERR, _("Can't bind to %s/udp: %s"), addrstr, strerror(errno));
- free(addrstr);
- return -1;
- }
-cp
- return nfd;
+#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
+ option = IP_PMTUDISC_DO;
+ setsockopt(nfd, IPPROTO_IP, IP_MTU_DISCOVER, (void *)&option, sizeof(option));
+#elif defined(IP_DONTFRAGMENT)
+ option = 1;
+ setsockopt(nfd, IPPROTO_IP, IP_DONTFRAGMENT, (void *)&option, sizeof(option));
+#endif
+
+#if defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
+ option = IPV6_PMTUDISC_DO;
+ setsockopt(nfd, IPPROTO_IPV6, IPV6_MTU_DISCOVER, (void *)&option, sizeof(option));
+#elif defined(IPV6_DONTFRAG)
+ option = 1;
+ setsockopt(nfd, IPPROTO_IPV6, IPV6_DONTFRAG, (void *)&option, sizeof(option));
+#endif
+
+ if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
+ closesocket(nfd);
+ addrstr = sockaddr2hostname(sa);
+ logger(mesh, MESHLINK_ERROR, "Can't bind to %s/udp: %s", addrstr, sockstrerror(sockerrno));
+ free(addrstr);
+ return -1;
+ }
+
+ return nfd;
+} /* int setup_vpn_in_socket */
+
+static void retry_outgoing_handler(event_loop_t *loop, void *data) {
+ assert(data);
+
+ meshlink_handle_t *mesh = loop->data;
+ outgoing_t *outgoing = data;
+ setup_outgoing_connection(mesh, outgoing);
}
-void retry_outgoing(outgoing_t *outgoing)
-{
- event_t *event;
-cp
- outgoing->timeout += 5;
- if(outgoing->timeout > maxtimeout)
- outgoing->timeout = maxtimeout;
-
- event = new_event();
- event->handler = (event_handler_t)setup_outgoing_connection;
- event->time = now + outgoing->timeout;
- event->data = outgoing;
- event_add(event);
-
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Trying to re-establish outgoing connection in %d seconds"), outgoing->timeout);
-cp
+void retry_outgoing(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+ outgoing->timeout += 5;
+
+ if(outgoing->timeout > mesh->maxtimeout) {
+ outgoing->timeout = mesh->maxtimeout;
+ }
+
+ timeout_add(&mesh->loop, &outgoing->ev, retry_outgoing_handler, outgoing, &(struct timeval) {
+ outgoing->timeout, rand() % 100000
+ });
+
+ logger(mesh, MESHLINK_INFO, "Trying to re-establish outgoing connection in %d seconds", outgoing->timeout);
}
-int setup_outgoing_socket(connection_t *c)
-{
- int option;
-cp
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_INFO, _("Trying to connect to %s (%s)"), c->name, c->hostname);
+void finish_connecting(meshlink_handle_t *mesh, connection_t *c) {
+ logger(mesh, MESHLINK_INFO, "Connected to %s", c->name);
- c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
+ c->last_ping_time = mesh->loop.now.tv_sec;
+ c->status.connecting = false;
- if(c->socket == -1)
- {
- syslog(LOG_ERR, _("Creating socket for %s failed: %s"), c->hostname, strerror(errno));
- return -1;
- }
+ send_id(mesh, c);
+}
- /* Optimize TCP settings */
+static void handle_meta_write(meshlink_handle_t *mesh, connection_t *c) {
+ if(c->outbuf.len <= c->outbuf.offset) {
+ return;
+ }
-#ifdef HAVE_LINUX
- option = 1;
- setsockopt(c->socket, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
+ ssize_t outlen = send(c->socket, c->outbuf.data + c->outbuf.offset, c->outbuf.len - c->outbuf.offset, MSG_NOSIGNAL);
- option = IPTOS_LOWDELAY;
- setsockopt(c->socket, SOL_IP, IP_TOS, &option, sizeof(option));
-#endif
+ if(outlen <= 0) {
+ if(!errno || errno == EPIPE) {
+ logger(mesh, MESHLINK_INFO, "Connection closed by %s", c->name);
+ } else if(sockwouldblock(sockerrno)) {
+ logger(mesh, MESHLINK_DEBUG, "Sending %lu bytes to %s would block", (unsigned long)(c->outbuf.len - c->outbuf.offset), c->name);
+ return;
+ } else {
+ logger(mesh, MESHLINK_ERROR, "Could not send %lu bytes of data to %s: %s", (unsigned long)(c->outbuf.len - c->outbuf.offset), c->name, strerror(errno));
+ }
+
+ terminate_connection(mesh, c, c->status.active);
+ return;
+ }
+
+ buffer_read(&c->outbuf, outlen);
+
+ if(!c->outbuf.len) {
+ io_set(&mesh->loop, &c->io, IO_READ);
+ }
+}
- /* Connect */
+static void handle_meta_io(event_loop_t *loop, void *data, int flags) {
+ meshlink_handle_t *mesh = loop->data;
+ connection_t *c = data;
- if(connect(c->socket, &c->address.sa, SALEN(c->address.sa)) == -1)
- {
- close(c->socket);
- syslog(LOG_ERR, _("Error while connecting to %s (%s): %s"), c->name, c->hostname, strerror(errno));
- return -1;
- }
+ if(c->status.connecting) {
+ c->status.connecting = false;
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_INFO, _("Connected to %s (%s)"), c->name, c->hostname);
-cp
- return 0;
+ int result;
+ socklen_t len = sizeof(result);
+ getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&result, &len);
+
+ if(!result) {
+ finish_connecting(mesh, c);
+ } else {
+ logger(mesh, MESHLINK_DEBUG, "Error while connecting to %s: %s", c->name, sockstrerror(result));
+ terminate_connection(mesh, c, false);
+ return;
+ }
+ }
+
+ if(flags & IO_WRITE) {
+ handle_meta_write(mesh, c);
+ } else {
+ handle_meta_connection_data(mesh, c);
+ }
+}
+
+// Find edges pointing to this node, and use them to build a list of unique, known addresses.
+static struct addrinfo *get_known_addresses(node_t *n) {
+ struct addrinfo *ai = NULL;
+
+ for splay_each(edge_t, e, n->edge_tree) {
+ if(!e->reverse) {
+ continue;
+ }
+
+ bool found = false;
+
+ for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
+ if(!sockaddrcmp(&e->reverse->address, (sockaddr_t *)aip->ai_addr)) {
+ found = true;
+ break;
+ }
+ }
+
+ if(found) {
+ continue;
+ }
+
+ // Create a new struct addrinfo, and put it at the head of the list.
+ struct addrinfo *nai = xzalloc(sizeof(*nai) + SALEN(e->reverse->address.sa));
+ nai->ai_next = ai;
+ ai = nai;
+
+ ai->ai_family = e->reverse->address.sa.sa_family;
+ ai->ai_socktype = SOCK_STREAM;
+ ai->ai_protocol = IPPROTO_TCP;
+ ai->ai_addrlen = SALEN(e->reverse->address.sa);
+ ai->ai_addr = (struct sockaddr *)(nai + 1);
+ memcpy(ai->ai_addr, &e->reverse->address, ai->ai_addrlen);
+ }
+
+ return ai;
+}
+
+// Build a list of recently seen addresses.
+static struct addrinfo *get_recent_addresses(node_t *n) {
+ struct addrinfo *ai = NULL;
+ struct addrinfo *aip;
+
+ for(int i = 0; i < 5; i++) {
+ if(!n->recent[i].sa.sa_family) {
+ break;
+ }
+
+ // Create a new struct addrinfo, and put it at the end of the list.
+ struct addrinfo *nai = xzalloc(sizeof(*nai) + SALEN(n->recent[i].sa));
+
+ if(!ai) {
+ ai = nai;
+ } else {
+ aip->ai_next = nai;
+ }
+
+ aip = nai;
+
+ nai->ai_family = n->recent[i].sa.sa_family;
+ nai->ai_socktype = SOCK_STREAM;
+ nai->ai_protocol = IPPROTO_TCP;
+ nai->ai_addrlen = SALEN(n->recent[i].sa);
+ nai->ai_addr = (struct sockaddr *)(nai + 1);
+ memcpy(nai->ai_addr, &n->recent[i], nai->ai_addrlen);
+ }
+
+ return ai;
+}
+
+// Free struct addrinfo list from get_known_addresses().
+static void free_known_addresses(struct addrinfo *ai) {
+ for(struct addrinfo *aip = ai, *next; aip; aip = next) {
+ next = aip->ai_next;
+ free(aip);
+ }
}
+static struct addrinfo *get_canonical_address(node_t *n) {
+ if(!n->canonical_address) {
+ return false;
+ }
-void finish_connecting(connection_t *c)
-{
-cp
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_INFO, _("Connected to %s (%s)"), c->name, c->hostname);
+ char *address = xstrdup(n->canonical_address);
+ char *port = strchr(address, ' ');
- c->last_ping_time = now;
+ if(!port) {
+ free(address);
+ return false;
+ }
- send_id(c);
-cp
+ *port++ = 0;
+
+ struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
+ free(address);
+
+ return ai;
}
-void do_outgoing_connection(connection_t *c)
-{
- char *address, *port;
- int option, result, flags;
-cp
+static bool get_next_outgoing_address(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+ (void)mesh;
+
+ bool start = false;
+
+ if(outgoing->state == OUTGOING_START) {
+ start = true;
+ outgoing->state = OUTGOING_CANONICAL;
+ }
+
+ if(outgoing->state == OUTGOING_CANONICAL) {
+ if(!outgoing->aip) {
+ outgoing->ai = get_canonical_address(outgoing->node);
+ outgoing->aip = outgoing->ai;
+ } else {
+ outgoing->aip = outgoing->aip->ai_next;
+ }
+
+ if(outgoing->aip) {
+ return true;
+ }
+
+ freeaddrinfo(outgoing->ai);
+ outgoing->ai = NULL;
+ outgoing->aip = NULL;
+ outgoing->state = OUTGOING_RECENT;
+ }
+
+ if(outgoing->state == OUTGOING_RECENT) {
+ if(!outgoing->aip) {
+ outgoing->ai = get_recent_addresses(outgoing->node);
+ outgoing->aip = outgoing->ai;
+ } else {
+ outgoing->aip = outgoing->aip->ai_next;
+ }
+
+ if(outgoing->aip) {
+ return true;
+ }
+
+ free_known_addresses(outgoing->ai);
+ outgoing->ai = NULL;
+ outgoing->aip = NULL;
+ outgoing->state = OUTGOING_KNOWN;
+ }
+
+ if(outgoing->state == OUTGOING_KNOWN) {
+ if(!outgoing->aip) {
+ outgoing->ai = get_known_addresses(outgoing->node);
+ outgoing->aip = outgoing->ai;
+ } else {
+ outgoing->aip = outgoing->aip->ai_next;
+ }
+
+ if(outgoing->aip) {
+ return true;
+ }
+
+ free_known_addresses(outgoing->ai);
+ outgoing->ai = NULL;
+ outgoing->aip = NULL;
+ outgoing->state = OUTGOING_END;
+ }
+
+ if(start) {
+ outgoing->state = OUTGOING_NO_KNOWN_ADDRESSES;
+ }
+
+ return false;
+}
+
+bool do_outgoing_connection(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+ struct addrinfo *proxyai = NULL;
+ int result;
+
begin:
- if(!c->outgoing->ai)
- {
- if(!c->outgoing->cfg)
- {
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_ERR, _("Could not set up a meta connection to %s"), c->name);
- c->status.remove = 1;
- do_prune = 1;
- retry_outgoing(c->outgoing);
- return;
- }
- get_config_string(c->outgoing->cfg, &address);
+ if(!get_next_outgoing_address(mesh, outgoing)) {
+ if(outgoing->state == OUTGOING_NO_KNOWN_ADDRESSES) {
+ logger(mesh, MESHLINK_ERROR, "No known addresses for %s", outgoing->node->name);
+ } else {
+ logger(mesh, MESHLINK_ERROR, "Could not set up a meta connection to %s", outgoing->node->name);
+ retry_outgoing(mesh, outgoing);
+ }
- if(!get_config_string(lookup_config(c->config_tree, "Port"), &port))
- asprintf(&port, "655");
+ return false;
+ }
- c->outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
- free(address);
- free(port);
+ connection_t *c = new_connection();
+ c->outgoing = outgoing;
- c->outgoing->aip = c->outgoing->ai;
- c->outgoing->cfg = lookup_config_next(c->config_tree, c->outgoing->cfg);
- }
+ memcpy(&c->address, outgoing->aip->ai_addr, outgoing->aip->ai_addrlen);
- if(!c->outgoing->aip)
- {
- freeaddrinfo(c->outgoing->ai);
- c->outgoing->ai = NULL;
- goto begin;
- }
+ char *hostname = sockaddr2hostname(&c->address);
- memcpy(&c->address, c->outgoing->aip->ai_addr, c->outgoing->aip->ai_addrlen);
- c->outgoing->aip = c->outgoing->aip->ai_next;
+ logger(mesh, MESHLINK_INFO, "Trying to connect to %s at %s", outgoing->node->name, hostname);
- if(c->hostname)
- free(c->hostname);
+ if(!mesh->proxytype) {
+ c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
+ configure_tcp(c);
+ } else {
+ proxyai = str2addrinfo(mesh->proxyhost, mesh->proxyport, SOCK_STREAM);
- c->hostname = sockaddr2hostname(&c->address);
+ if(!proxyai) {
+ free_connection(c);
+ free(hostname);
+ goto begin;
+ }
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_INFO, _("Trying to connect to %s (%s)"), c->name, c->hostname);
+ logger(mesh, MESHLINK_INFO, "Using proxy at %s port %s", mesh->proxyhost, mesh->proxyport);
+ c->socket = socket(proxyai->ai_family, SOCK_STREAM, IPPROTO_TCP);
+ configure_tcp(c);
+ }
- c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
+ if(c->socket == -1) {
+ logger(mesh, MESHLINK_ERROR, "Creating socket for %s at %s failed: %s", c->name, hostname, sockstrerror(sockerrno));
+ free_connection(c);
+ free(hostname);
+ goto begin;
+ }
- if(c->socket == -1)
- {
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_ERR, _("Creating socket for %s failed: %s"), c->hostname, strerror(errno));
+ free(hostname);
- goto begin;
- }
+#ifdef FD_CLOEXEC
+ fcntl(c->socket, F_SETFD, FD_CLOEXEC);
+#endif
- /* Optimize TCP settings */
+#if defined(IPV6_V6ONLY)
-#ifdef HAVE_LINUX
- option = 1;
- setsockopt(c->socket, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
+ if(c->address.sa.sa_family == AF_INET6) {
+ static const int option = 1;
+ setsockopt(c->socket, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof(option));
+ }
- option = IPTOS_LOWDELAY;
- setsockopt(c->socket, SOL_IP, IP_TOS, &option, sizeof(option));
#endif
- /* Non-blocking */
+ bind_to_address(mesh, c);
+
+ /* Connect */
- flags = fcntl(c->socket, F_GETFL);
+ if(!mesh->proxytype) {
+ result = connect(c->socket, &c->address.sa, SALEN(c->address.sa));
+ } else {
+ result = connect(c->socket, proxyai->ai_addr, proxyai->ai_addrlen);
+ freeaddrinfo(proxyai);
+ }
- if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0)
- {
- syslog(LOG_ERR, _("fcntl for %s: %s"), c->hostname, strerror(errno));
- }
+ if(result == -1 && !sockinprogress(sockerrno)) {
+ logger(mesh, MESHLINK_ERROR, "Could not connect to %s: %s", outgoing->node->name, sockstrerror(sockerrno));
+ free_connection(c);
+
+ goto begin;
+ }
- /* Connect */
+ /* Now that there is a working socket, fill in the rest and register this connection. */
- result = connect(c->socket, &c->address.sa, SALEN(c->address.sa));
+ c->status.connecting = true;
+ c->status.initiator = true;
+ c->name = xstrdup(outgoing->node->name);
+ c->last_ping_time = mesh->loop.now.tv_sec;
- if(result == -1)
- {
- if(errno == EINPROGRESS)
- {
- c->status.connecting = 1;
- return;
+ connection_add(mesh, c);
+
+ io_add(&mesh->loop, &c->io, handle_meta_io, c, c->socket, IO_READ | IO_WRITE);
+
+ return true;
+}
+
+void setup_outgoing_connection(meshlink_handle_t *mesh, outgoing_t *outgoing) {
+ timeout_del(&mesh->loop, &outgoing->ev);
+
+ if(outgoing->node->connection) {
+ logger(mesh, MESHLINK_INFO, "Already connected to %s", outgoing->node->name);
+
+ outgoing->node->connection->outgoing = outgoing;
+ return;
}
- close(c->socket);
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_ERR, _("%s: %s"), c->hostname, strerror(errno));
+ if(outgoing->ai) {
+ if(outgoing->state == OUTGOING_RECENT || outgoing->state == OUTGOING_KNOWN) {
+ free_known_addresses(outgoing->ai);
+ } else {
+ freeaddrinfo(outgoing->ai);
+ }
+ }
+
+ outgoing->state = OUTGOING_START;
- goto begin;
- }
+ if(outgoing->node->status.blacklisted) {
+ return;
+ }
+
+ if(mesh->connection_try_cb) {
+ mesh->connection_try_cb(mesh, (meshlink_node_t *)outgoing->node);
+ }
- finish_connecting(c);
- return;
-cp
+ do_outgoing_connection(mesh, outgoing);
}
-void setup_outgoing_connection(outgoing_t *outgoing)
-{
- connection_t *c;
- node_t *n;
-cp
- n = lookup_node(outgoing->name);
-
- if(n)
- if(n->connection)
- {
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_INFO, _("Already connected to %s"), outgoing->name);
- n->connection->outgoing = outgoing;
- return;
- }
-
- c = new_connection();
- c->name = xstrdup(outgoing->name);
- c->outcipher = myself->connection->outcipher;
- c->outdigest = myself->connection->outdigest;
- c->outmaclength = myself->connection->outmaclength;
- c->outcompression = myself->connection->outcompression;
-
- init_configuration(&c->config_tree);
- read_connection_config(c);
-
- outgoing->cfg = lookup_config(c->config_tree, "Address");
-
- if(!outgoing->cfg)
- {
- syslog(LOG_ERR, _("No address specified for %s"), c->name);
- free_connection(c);
- free(outgoing->name);
- free(outgoing);
- return;
- }
-
- c->outgoing = outgoing;
- c->last_ping_time = now;
-
- connection_add(c);
-
- do_outgoing_connection(c);
+/// Delayed close of a filedescriptor.
+static void tarpit(meshlink_handle_t *mesh, int fd) {
+ if(!fd) {
+ return;
+ }
+
+ if(mesh->pits[mesh->next_pit]) {
+ closesocket(mesh->pits[mesh->next_pit]);
+ }
+
+ mesh->pits[mesh->next_pit++] = fd;
+
+ if(mesh->next_pit >= (int)(sizeof mesh->pits / sizeof mesh->pits[0])) {
+ mesh->next_pit = 0;
+ }
}
/*
accept a new tcp connect and create a
new connection
*/
-int handle_new_meta_connection(int sock)
-{
- connection_t *c;
- sockaddr_t sa;
- int fd, len = sizeof(sa);
-cp
- if((fd = accept(sock, &sa.sa, &len)) < 0)
- {
- syslog(LOG_ERR, _("Accepting a new connection failed: %s"), strerror(errno));
- return -1;
- }
-
- c = new_connection();
- c->outcipher = myself->connection->outcipher;
- c->outdigest = myself->connection->outdigest;
- c->outmaclength = myself->connection->outmaclength;
- c->outcompression = myself->connection->outcompression;
-
- c->address = sa;
- c->hostname = sockaddr2hostname(&sa);
- c->socket = fd;
- c->last_ping_time = now;
-
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Connection from %s"), c->hostname);
-
- connection_add(c);
-
- c->allow_request = ID;
- send_id(c);
-cp
- return 0;
+void handle_new_meta_connection(event_loop_t *loop, void *data, int flags) {
+ (void)flags;
+ meshlink_handle_t *mesh = loop->data;
+ listen_socket_t *l = data;
+ connection_t *c;
+ sockaddr_t sa;
+ int fd;
+ socklen_t len = sizeof(sa);
+
+ memset(&sa, 0, sizeof(sa));
+
+ fd = accept(l->tcp.fd, &sa.sa, &len);
+
+ if(fd < 0) {
+ if(errno == EINVAL) { // TODO: check if Windows agrees
+ event_loop_stop(loop);
+ return;
+ }
+
+ logger(mesh, MESHLINK_ERROR, "Accepting a new connection failed: %s", sockstrerror(sockerrno));
+ return;
+ }
+
+ sockaddrunmap(&sa);
+
+ /* Rate limit incoming connections to max_connection_burst/second. */
+
+ if(mesh->loop.now.tv_sec != mesh->connection_burst_time) {
+ mesh->connection_burst_time = mesh->loop.now.tv_sec;
+ mesh->connection_burst = 0;
+ }
+
+ if(mesh->connection_burst >= max_connection_burst) {
+ tarpit(mesh, fd);
+ return;
+ }
+
+ mesh->connection_burst++;
+
+ // Accept the new connection
+
+ c = new_connection();
+ c->name = xstrdup("<unknown>");
+
+ c->address = sa;
+ c->socket = fd;
+ c->last_ping_time = mesh->loop.now.tv_sec;
+
+ char *hostname = sockaddr2hostname(&sa);
+ logger(mesh, MESHLINK_INFO, "Connection from %s", hostname);
+ free(hostname);
+
+ io_add(&mesh->loop, &c->io, handle_meta_io, c, c->socket, IO_READ);
+
+ configure_tcp(c);
+
+ connection_add(mesh, c);
+
+ c->allow_request = ID;
+ send_id(mesh, c);
+}
+
+static void free_outgoing(outgoing_t *outgoing) {
+ meshlink_handle_t *mesh = outgoing->node->mesh;
+
+ timeout_del(&mesh->loop, &outgoing->ev);
+
+ if(outgoing->ai) {
+ if(outgoing->state == OUTGOING_RECENT || outgoing->state == OUTGOING_KNOWN) {
+ free_known_addresses(outgoing->ai);
+ } else {
+ freeaddrinfo(outgoing->ai);
+ }
+ }
+
+ free(outgoing);
}
-void try_outgoing_connections(void)
-{
- static config_t *cfg = NULL;
- char *name;
- outgoing_t *outgoing;
-cp
- for(cfg = lookup_config(config_tree, "ConnectTo"); cfg; cfg = lookup_config_next(config_tree, cfg))
- {
- get_config_string(cfg, &name);
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Invalid name for outgoing connection in %s line %d"), cfg->file, cfg->line);
- free(name);
- continue;
- }
-
- outgoing = xmalloc_and_zero(sizeof(*outgoing));
- outgoing->name = name;
- setup_outgoing_connection(outgoing);
- }
+void init_outgoings(meshlink_handle_t *mesh) {
+ mesh->outgoings = list_alloc((list_action_t)free_outgoing);
+}
+
+void exit_outgoings(meshlink_handle_t *mesh) {
+ if(mesh->outgoings) {
+ list_delete_list(mesh->outgoings);
+ mesh->outgoings = NULL;
+ }
}