X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fnet.c;h=84625917198c8cda4a339c7529f84a52b5e43b0c;hb=4bfb68d289305a884d0f11bd4fa216a8cc0b36ac;hp=0e251bee67040ee7dd6a9cc58e29ca3517014180;hpb=85adeef21275633b78a234b2660cbe3bc9dd2c33;p=meshlink diff --git a/src/net.c b/src/net.c index 0e251bee..84625917 100644 --- a/src/net.c +++ b/src/net.c @@ -1,7 +1,6 @@ /* net.c -- most of the network code - Copyright (C) 1998,1999,2000 Ivo Timmermans , - 2000 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 @@ -13,1162 +12,641 @@ 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.c,v 1.35.4.36 2000/10/15 00:59:34 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 -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* Next two includes are for tun/tap support */ -#include -#include "/usr/src/linux/include/linux/if_tun.h" - -#include -#include +#include "system.h" +#include "utils.h" #include "conf.h" -#include "encr.h" +#include "connection.h" +#include "graph.h" +#include "logger.h" +#include "meshlink_internal.h" +#include "meta.h" #include "net.h" #include "netutl.h" #include "protocol.h" -#include "meta.h" +#include "xalloc.h" -#include "system.h" +#include -int tap_fd = -1; +#if !defined(min) +static inline int min(int a, int b) { + return a < b ? a : b; +} +#endif -int total_tap_in = 0; -int total_tap_out = 0; -int total_socket_in = 0; -int total_socket_out = 0; +/* + Terminate a connection: + - Mark it as inactive + - Remove the edge representing this connection + - Kill it with fire + - Check if we need to retry making an outgoing connection +*/ +void terminate_connection(meshlink_handle_t *mesh, connection_t *c, bool report) { + logger(mesh, MESHLINK_INFO, "Closing connection with %s", c->name); -int upstreamindex = 0; -static int seconds_till_retry; + c->status.active = false; -char *unknown = NULL; + if(c->node && c->node->connection == c) { + c->node->connection = NULL; + } -/* - strip off the MAC adresses of an ethernet frame -*/ -void strip_mac_addresses(vpn_packet_t *p) -{ -cp - memmove(p->data, p->data + 12, p->len -= 12); -cp -} + if(c->edge) { + if(report) { + send_del_edge(mesh, mesh->everyone, c->edge); + } -/* - reassemble MAC addresses -*/ -void add_mac_addresses(vpn_packet_t *p) -{ -cp - memcpy(p->data + 12, p->data, p->len); - p->len += 12; - p->data[0] = p->data[6] = 0xfe; - p->data[1] = p->data[7] = 0xfd; - /* Really evil pointer stuff just below! */ - *((ip_t*)(&p->data[2])) = (ip_t)(htonl(myself->address)); - *((ip_t*)(&p->data[8])) = *((ip_t*)(&p->data[26])); -cp -} + edge_del(mesh, c->edge); + c->edge = NULL; -int xsend(conn_list_t *cl, vpn_packet_t *inpkt) -{ - vpn_packet_t outpkt; - int outlen, outpad; -cp - outpkt.len = inpkt->len; - EVP_EncryptInit(cl->cipher_pktctx, cl->cipher_pkttype, cl->cipher_pktkey, NULL); - EVP_EncryptUpdate(cl->cipher_pktctx, outpkt.data, &outlen, inpkt->data, inpkt->len); - EVP_EncryptFinal(cl->cipher_pktctx, outpkt.data + outlen, &outpad); - outlen += outpad; - - if(debug_lvl > 3) - syslog(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"), - outlen, cl->name, cl->hostname); - - total_socket_out += outlen; - - cl->want_ping = 1; - - if((send(cl->socket, (char *) &(outpkt.len), outlen + 2, 0)) < 0) - { - syslog(LOG_ERR, _("Error sending packet to %s (%s): %m"), - cl->name, cl->hostname); - return -1; - } -cp - return 0; -} + /* Run MST and SSSP algorithms */ -int xrecv(vpn_packet_t *inpkt) -{ - vpn_packet_t outpkt; - int outlen, outpad; -cp - if(debug_lvl > 3) - syslog(LOG_ERR, _("Receiving packet of %d bytes"), - inpkt->len); - - outpkt.len = inpkt->len; - EVP_DecryptInit(myself->cipher_pktctx, myself->cipher_pkttype, myself->cipher_pktkey, NULL); - EVP_DecryptUpdate(myself->cipher_pktctx, outpkt.data, &outlen, inpkt->data, inpkt->len); - /* FIXME: grok DecryptFinal - EVP_DecryptFinal(myself->cipher_pktctx, outpkt.data + outlen, &outpad); - */ - - add_mac_addresses(&outpkt); - - if(write(tap_fd, outpkt.data, outpkt.len) < 0) - syslog(LOG_ERR, _("Can't write to tap device: %m")); - else - total_tap_out += outpkt.len; -cp - return 0; -} + graph(mesh); -/* - add the given packet of size s to the - queue q, be it the send or receive queue -*/ -void add_queue(packet_queue_t **q, void *packet, size_t s) -{ - queue_element_t *e; -cp - e = xmalloc(sizeof(*e)); - e->packet = xmalloc(s); - memcpy(e->packet, packet, s); - - if(!*q) - { - *q = xmalloc(sizeof(**q)); - (*q)->head = (*q)->tail = NULL; - } - - e->next = NULL; /* We insert at the tail */ - - if((*q)->tail) /* Do we have a tail? */ - { - (*q)->tail->next = e; - e->prev = (*q)->tail; - } - else /* No tail -> no head too */ - { - (*q)->head = e; - e->prev = NULL; - } - - (*q)->tail = e; -cp -} + /* If the node is not reachable anymore but we remember it had an edge to us, clean it up */ -/* Remove a queue element */ -void del_queue(packet_queue_t **q, queue_element_t *e) -{ -cp - free(e->packet); - - if(e->next) /* There is a successor, so we are not tail */ - { - if(e->prev) /* There is a predecessor, so we are not head */ - { - e->next->prev = e->prev; - e->prev->next = e->next; - } - else /* We are head */ - { - e->next->prev = NULL; - (*q)->head = e->next; - } - } - else /* We are tail (or all alone!) */ - { - if(e->prev) /* We are not alone :) */ - { - e->prev->next = NULL; - (*q)->tail = e->prev; - } - else /* Adieu */ - { - free(*q); - *q = NULL; - } - } - - free(e); -cp -} + if(report && c->node && !c->node->status.reachable) { + edge_t *e; + e = lookup_edge(c->node, mesh->self); -/* - flush a queue by calling function for - each packet, and removing it when that - returned a zero exit code -*/ -void flush_queue(conn_list_t *cl, packet_queue_t **pq, - int (*function)(conn_list_t*,void*)) -{ - queue_element_t *p, *next = NULL; -cp - for(p = (*pq)->head; p != NULL; ) - { - next = p->next; - - if(!function(cl, p->packet)) - del_queue(pq, p); - - p = next; - } - - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Queue flushed")); -cp -} + if(e) { + send_del_edge(mesh, mesh->everyone, e); + edge_del(mesh, e); + } + } + } -/* - flush the send&recv queues - void because nothing goes wrong here, packets - remain in the queue if something goes wrong -*/ -void flush_queues(conn_list_t *cl) -{ -cp - if(cl->sq) - { - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Flushing send queue for %s (%s)"), - cl->name, cl->hostname); - flush_queue(cl, &(cl->sq), xsend); - } - - if(cl->rq) - { - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Flushing receive queue for %s (%s)"), - cl->name, cl->hostname); - flush_queue(cl, &(cl->rq), xrecv); - } -cp -} + outgoing_t *outgoing = c->outgoing; + connection_del(mesh, c); -/* - send a packet to the given vpn ip. -*/ -int send_packet(ip_t to, vpn_packet_t *packet) -{ - conn_list_t *cl; -cp - if((cl = lookup_conn_list_ipv4(to)) == NULL) - { - if(debug_lvl > 3) - { - syslog(LOG_NOTICE, _("Trying to look up %d.%d.%d.%d in connection list failed!"), - IP_ADDR_V(to)); - } - - return -1; - } - - /* If we ourselves have indirectdata flag set, we should send only to our uplink! */ - - /* FIXME - check for indirection and reprogram it The Right Way(tm) this time. */ - - if(!cl->status.dataopen) - if(setup_vpn_connection(cl) < 0) - { - syslog(LOG_ERR, _("Could not open UDP connection to %s (%s)"), - cl->name, cl->hostname); - return -1; - } - - if(!cl->status.validkey) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("No valid key known yet for %s (%s), queueing packet"), - cl->name, cl->hostname); - add_queue(&(cl->sq), packet, packet->len + 2); - if(!cl->status.waitingforkey) - send_req_key(myself, cl); /* Keys should be sent to the host running the tincd */ - return 0; - } - - if(!cl->status.active) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("%s (%s) is not ready, queueing packet"), - cl->name, cl->hostname); - add_queue(&(cl->sq), packet, packet->len + 2); - return 0; /* We don't want to mess up, do we? */ - } - - /* can we send it? can we? can we? huh? */ -cp - return xsend(cl, packet); -} + /* Check if this was our outgoing connection */ -/* - open the local ethertap device -*/ -int setup_tap_fd(void) -{ - int nfd; - const char *tapfname; - config_t const *cfg; - struct ifreq ifr; -cp - if((cfg = get_config_val(config, tapdevice))) - tapfname = cfg->data.ptr; - else - tapfname = "/dev/misc/net/tun"; -cp - if((nfd = open(tapfname, O_RDWR | O_NONBLOCK)) < 0) - { - syslog(LOG_ERR, _("Could not open %s: %m"), tapfname); - return -1; - } -cp - tap_fd = nfd; - - /* Ok now check if this is an old ethertap or a new tun/tap thingie */ - - memset(&ifr, 0, sizeof(ifr)); -cp - ifr.ifr_flags = IFF_TAP; - if (netname) - strncpy(ifr.ifr_name, netname, IFNAMSIZ); -cp - if (!ioctl(tap_fd, TUNSETIFF, (void *) &ifr)) - { - syslog(LOG_INFO, _("%s is a new style tun/tap device"), tapfname); - if((cfg = get_config_val(config, tapsubnet)) == NULL) - syslog(LOG_INFO, _("tun/tap device will be left unconfigured")); - else - /* Setup inetaddr/netmask etc */; - } - -cp - return 0; -} + if(outgoing) { + do_outgoing_connection(mesh, outgoing); + } -/* - set up the socket that we listen on for incoming - (tcp) connections -*/ -int setup_listen_meta_socket(int port) -{ - int nfd, flags; - struct sockaddr_in a; - const int one = 1; - config_t const *cfg; -cp - if((nfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) - { - syslog(LOG_ERR, _("Creating metasocket failed: %m")); - return -1; - } - - if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) - { - syslog(LOG_ERR, _("setsockopt: %m")); - return -1; - } - - if(setsockopt(nfd, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof(one))) - { - syslog(LOG_ERR, _("setsockopt: %m")); - return -1; - } - - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("fcntl: %m")); - return -1; - } - - if((cfg = get_config_val(config, interface))) - { - if(setsockopt(nfd, SOL_SOCKET, SO_KEEPALIVE, cfg->data.ptr, strlen(cfg->data.ptr))) - { - syslog(LOG_ERR, _("Unable to bind listen socket to interface %s: %m"), cfg->data.ptr); - return -1; - } - } - - memset(&a, 0, sizeof(a)); - a.sin_family = AF_INET; - a.sin_port = htons(port); - - if((cfg = get_config_val(config, interfaceip))) - a.sin_addr.s_addr = htonl(cfg->data.ip->ip); - else - a.sin_addr.s_addr = htonl(INADDR_ANY); - - if(bind(nfd, (struct sockaddr *)&a, sizeof(struct sockaddr))) - { - syslog(LOG_ERR, _("Can't bind to port %hd/tcp: %m"), port); - return -1; - } - - if(listen(nfd, 3)) - { - syslog(LOG_ERR, _("listen: %m")); - return -1; - } -cp - return nfd; -} +#ifndef HAVE_MINGW + /* Clean up dead proxy processes */ -/* - setup the socket for incoming encrypted - data (the udp part) -*/ -int setup_vpn_in_socket(int port) -{ - int nfd, flags; - struct sockaddr_in a; - const int one = 1; -cp - if((nfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) - { - syslog(LOG_ERR, _("Creating socket failed: %m")); - return -1; - } - - if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one))) - { - syslog(LOG_ERR, _("setsockopt: %m")); - return -1; - } - - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("fcntl: %m")); - return -1; - } - - memset(&a, 0, sizeof(a)); - a.sin_family = AF_INET; - a.sin_port = htons(port); - a.sin_addr.s_addr = htonl(INADDR_ANY); - - if(bind(nfd, (struct sockaddr *)&a, sizeof(struct sockaddr))) - { - syslog(LOG_ERR, _("Can't bind to port %hd/udp: %m"), port); - return -1; - } -cp - return nfd; -} + while(waitpid(-1, NULL, WNOHANG) > 0); -/* - setup an outgoing meta (tcp) socket -*/ -int setup_outgoing_meta_socket(conn_list_t *cl) -{ - int flags; - struct sockaddr_in a; - config_t const *cfg; -cp - if(debug_lvl > 0) - syslog(LOG_INFO, _("Trying to connect to %s"), cl->hostname); - - if((cfg = get_config_val(cl->config, port)) == NULL) - cl->port = 655; - else - cl->port = cfg->data.val; - - cl->meta_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); - if(cl->meta_socket == -1) - { - syslog(LOG_ERR, _("Creating socket for %s port %d failed: %m"), - cl->hostname, cl->port); - return -1; - } - - a.sin_family = AF_INET; - a.sin_port = htons(cl->port); - a.sin_addr.s_addr = htonl(cl->address); - - if(connect(cl->meta_socket, (struct sockaddr *)&a, sizeof(a)) == -1) - { - syslog(LOG_ERR, _("%s port %hd: %m"), cl->hostname, cl->port); - return -1; - } - - flags = fcntl(cl->meta_socket, F_GETFL); - if(fcntl(cl->meta_socket, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("fcntl for %s port %d: %m"), - cl->hostname, cl->port); - return -1; - } - - if(debug_lvl > 0) - syslog(LOG_INFO, _("Connected to %s port %hd"), - cl->hostname, cl->port); -cp - return 0; +#endif } /* - setup an outgoing connection. It's not - necessary to also open an udp socket as - well, because the other host will initiate - an authentication sequence during which - we will do just that. + Check if the other end is active. + If we have sent packets, but didn't receive any, + then possibly the other end is dead. We send a + PING request over the meta connection. If the other + end does not reply in time, we consider them dead + and close the connection. */ -int setup_outgoing_connection(char *hostname) -{ - conn_list_t *ncn; - struct hostent *h; -cp - if(!(h = gethostbyname(hostname))) - { - syslog(LOG_ERR, _("Error looking up `%s': %m"), hostname); - return -1; - } - - ncn = new_conn_list(); - ncn->address = ntohl(*((ip_t*)(h->h_addr_list[0]))); - ncn->hostname = hostlookup(htonl(ncn->address)); - - if(setup_outgoing_meta_socket(ncn) < 0) - { - syslog(LOG_ERR, _("Could not set up a meta connection to %s"), - ncn->hostname); - free_conn_list(ncn); - return -1; - } - - ncn->status.meta = 1; - ncn->status.outgoing = 1; - ncn->next = conn_list; - conn_list = ncn; -cp - return 0; -} +static void timeout_handler(event_loop_t *loop, void *data) { + meshlink_handle_t *mesh = loop->data; + logger(mesh, MESHLINK_DEBUG, "timeout_handler()"); + + for list_each(connection_t, c, mesh->connections) { + // Also make sure that if outstanding key requests for the UDP counterpart of a connection has timed out, we restart it. + if(c->node) { + if(c->node->status.waitingforkey && c->node->last_req_key + mesh->pingtimeout <= mesh->loop.now.tv_sec) { + send_req_key(mesh, c->node); + } + } + + if(c->last_ping_time + mesh->pingtimeout <= mesh->loop.now.tv_sec) { + if(c->status.active) { + if(c->status.pinged) { + logger(mesh, MESHLINK_INFO, "%s didn't respond to PING in %ld seconds", c->name, (long)mesh->loop.now.tv_sec - c->last_ping_time); + } else if(c->last_ping_time + mesh->pinginterval <= mesh->loop.now.tv_sec) { + send_ping(mesh, c); + continue; + } else { + continue; + } + } else { + if(c->status.connecting) { + logger(mesh, MESHLINK_WARNING, "Timeout while connecting to %s", c->name); + } else { + logger(mesh, MESHLINK_WARNING, "Timeout from %s during authentication", c->name); + } + } + + terminate_connection(mesh, c, c->status.active); + } + } -/* - set up the local sockets (listen only) -*/ -int setup_myself(void) -{ - config_t const *cfg; -cp - myself = new_conn_list(); - - asprintf(&myself->hostname, "MYSELF"); /* FIXME? Do hostlookup on ourselves? */ - myself->flags = 0; - myself->protocol_version = PROT_CURRENT; - - if(!(cfg = get_config_val(config, tincname))) /* Not acceptable */ - { - syslog(LOG_ERR, _("Name for tinc daemon required!")); - return -1; - } - else - myself->name = (char*)cfg->data.val; - - if(check_id(myself->name)) - { - syslog(LOG_ERR, _("Invalid name for myself!")); - return -1; - } - - if(read_host_config(myself)) - { - syslog(LOG_ERR, _("Cannot open host configuration file for myself!")); - return -1; - } - - if(!(cfg = get_config_val(myself->config, port))) - myself->port = 655; - else - myself->port = cfg->data.val; - - if((cfg = get_config_val(myself->config, indirectdata))) - if(cfg->data.val == stupid_true) - myself->flags |= EXPORTINDIRECTDATA; - - if((cfg = get_config_val(myself->config, tcponly))) - if(cfg->data.val == stupid_true) - myself->flags |= TCPONLY; - - if((myself->meta_socket = setup_listen_meta_socket(myself->port)) < 0) - { - syslog(LOG_ERR, _("Unable to set up a listening socket!")); - return -1; - } - - if((myself->socket = setup_vpn_in_socket(myself->port)) < 0) - { - syslog(LOG_ERR, _("Unable to set up an incoming vpn data socket!")); - close(myself->meta_socket); - return -1; - } - - myself->status.active = 1; - - syslog(LOG_NOTICE, _("Ready: listening on port %hd"), myself->port); -cp - return 0; + timeout_set(&mesh->loop, data, &(struct timeval) { + mesh->pingtimeout, rand() % 100000 + }); } -RETSIGTYPE -sigalrm_handler(int a) -{ - config_t const *cfg; -cp -/* FIXME! Use name instead of upstreamip. - cfg = get_next_config_val(config, upstreamip, upstreamindex++); -*/ - while(cfg) - { - if(!setup_outgoing_connection(cfg->data.ptr)) /* function returns 0 when there are no problems */ - { - signal(SIGALRM, SIG_IGN); - return; - } -// cfg = get_next_config_val(config, upstreamip, upstreamindex++); /* Or else we try the next ConnectTo line */ - } - - signal(SIGALRM, sigalrm_handler); - upstreamindex = 0; - seconds_till_retry += 5; - if(seconds_till_retry > MAXTIMEOUT) /* Don't wait more than MAXTIMEOUT seconds. */ - seconds_till_retry = MAXTIMEOUT; - syslog(LOG_ERR, _("Still failed to connect to other, will retry in %d seconds"), - seconds_till_retry); - alarm(seconds_till_retry); -cp -} +// devclass asc, last_successfull_connection desc +static int node_compare_devclass_asc_lsc_desc(const void *a, const void *b) { + const node_t *na = a, *nb = b; -/* - setup all initial network connections -*/ -int setup_network_connections(void) -{ - config_t const *cfg; -cp - if((cfg = get_config_val(config, pingtimeout)) == NULL) - timeout = 5; - else - timeout = cfg->data.val; - - if(setup_tap_fd() < 0) - return -1; - - if(setup_myself() < 0) - return -1; - -// if((cfg = get_next_config_val(config, upstreamip, upstreamindex++)) == NULL) - /* No upstream IP given, we're listen only. */ - return 0; - - while(cfg) - { - if(!setup_outgoing_connection(cfg->data.ptr)) /* function returns 0 when there are no problems */ - return 0; -// cfg = get_next_config_val(config, upstreamip, upstreamindex++); /* Or else we try the next ConnectTo line */ - } - - signal(SIGALRM, sigalrm_handler); - upstreamindex = 0; - seconds_till_retry = MAXTIMEOUT; - syslog(LOG_NOTICE, _("Trying to re-establish outgoing connection in %d seconds"), seconds_till_retry); - alarm(seconds_till_retry); -cp - return 0; -} + if(na->devclass < nb->devclass) { + return -1; + } -/* - close all open network connections -*/ -void close_network_connections(void) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.dataopen) - { - shutdown(p->socket, 0); /* No more receptions */ - close(p->socket); + if(na->devclass > nb->devclass) { + return 1; } - if(p->status.meta) - { - send_termreq(p); - shutdown(p->meta_socket, 0); /* No more receptions */ - close(p->meta_socket); - } - } - - if(myself) - if(myself->status.active) - { - close(myself->meta_socket); - close(myself->socket); - } - - close(tap_fd); - destroy_conn_list(); - - syslog(LOG_NOTICE, _("Terminating")); -cp - return; -} -/* - create a data (udp) socket -*/ -int setup_vpn_connection(conn_list_t *cl) -{ - int nfd, flags; - struct sockaddr_in a; -cp - if(debug_lvl > 0) - syslog(LOG_DEBUG, _("Opening UDP socket to %s"), cl->hostname); - - nfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); - if(nfd == -1) - { - syslog(LOG_ERR, _("Creating UDP socket failed: %m")); - return -1; - } - - a.sin_family = AF_INET; - a.sin_port = htons(cl->port); - a.sin_addr.s_addr = htonl(cl->address); - - if(connect(nfd, (struct sockaddr *)&a, sizeof(a)) == -1) - { - syslog(LOG_ERR, _("Connecting to %s port %d failed: %m"), - cl->hostname, cl->port); - return -1; - } - - flags = fcntl(nfd, F_GETFL); - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) - { - syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%m %s (%s)"), __FILE__, __LINE__, nfd, - cl->name, cl->hostname); - return -1; - } - - cl->socket = nfd; - cl->status.dataopen = 1; -cp - return 0; -} + if(na->last_successfull_connection == nb->last_successfull_connection) { + return 0; + } -/* - handle an incoming tcp connect call and open - a connection to it. -*/ -conn_list_t *create_new_connection(int sfd) -{ - conn_list_t *p; - struct sockaddr_in ci; - int len = sizeof(ci); -cp - p = new_conn_list(); - - if(getpeername(sfd, &ci, &len) < 0) - { - syslog(LOG_ERR, _("Error: getpeername: %m")); - return NULL; - } - - p->name = unknown; - p->address = ntohl(ci.sin_addr.s_addr); - p->hostname = hostlookup(ci.sin_addr.s_addr); - p->meta_socket = sfd; - p->status.meta = 1; - p->buffer = xmalloc(MAXBUFSIZE); - p->buflen = 0; - p->last_ping_time = time(NULL); - p->want_ping = 0; - - if(debug_lvl > 0) - syslog(LOG_NOTICE, _("Connection from %s port %d"), - p->hostname, htons(ci.sin_port)); - - if(send_id(p) < 0) - { - free_conn_list(p); - return NULL; - } -cp - return p; + if(na->last_successfull_connection == 0 || na->last_successfull_connection > nb->last_successfull_connection) { + return -1; + } + + if(nb->last_successfull_connection == 0 || na->last_successfull_connection < nb->last_successfull_connection) { + return 1; + } + + if(na < nb) { + return -1; + } + + if(na > nb) { + return 1; + } + + return 0; } -/* - put all file descriptors in an fd_set array -*/ -void build_fdset(fd_set *fs) -{ - conn_list_t *p; -cp - FD_ZERO(fs); - - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.meta) - FD_SET(p->meta_socket, fs); - if(p->status.dataopen) - FD_SET(p->socket, fs); - } - - FD_SET(myself->meta_socket, fs); - FD_SET(myself->socket, fs); - FD_SET(tap_fd, fs); -cp +// last_successfull_connection desc +static int node_compare_lsc_desc(const void *a, const void *b) { + const node_t *na = a, *nb = b; + + if(na->last_successfull_connection == nb->last_successfull_connection) { + return 0; + } + + if(na->last_successfull_connection == 0 || na->last_successfull_connection > nb->last_successfull_connection) { + return -1; + } + + if(nb->last_successfull_connection == 0 || na->last_successfull_connection < nb->last_successfull_connection) { + return 1; + } + + if(na < nb) { + return -1; + } + + if(na > nb) { + return 1; + } + + return 0; } -/* - receive incoming data from the listening - udp socket and write it to the ethertap - device after being decrypted -*/ -int handle_incoming_vpn_data() -{ - vpn_packet_t pkt; - int lenin; - int x, l = sizeof(x); -cp - if(getsockopt(myself->socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0) - { - syslog(LOG_ERR, _("This is a bug: %s:%d: %d:%m"), - __FILE__, __LINE__, myself->socket); - return -1; - } - if(x) - { - syslog(LOG_ERR, _("Incoming data socket error: %s"), strerror(x)); - return -1; - } - - if(recvfrom(myself->socket, (char *) &(pkt.len), MTU, 0, NULL, NULL) <= 0) - { - syslog(LOG_ERR, _("Receiving packet failed: %m")); - return -1; - } - -cp - return xrecv(&pkt); +// devclass desc +static int node_compare_devclass_desc(const void *a, const void *b) { + const node_t *na = a, *nb = b; + + if(na->devclass < nb->devclass) { + return -1; + } + + if(na->devclass > nb->devclass) { + return 1; + } + + if(na < nb) { + return -1; + } + + if(na > nb) { + return 1; + } + + return 0; } + /* - terminate a connection and notify the other - end before closing the sockets -*/ -void terminate_connection(conn_list_t *cl) + +autoconnect() { - conn_list_t *p; + timeout = 5 -cp - if(cl->status.remove) - return; + // find the best one for initial connect - if(debug_lvl > 0) - syslog(LOG_NOTICE, _("Closing connection with %s (%s)"), - cl->name, cl->hostname); - - if(cl->socket) - close(cl->socket); - if(cl->status.meta) - close(cl->meta_socket); + if cur < min + newcon = + first from nodes + where dclass <= my.dclass and !connection and (timestamp - last_retry) > retry_timeout + order by dclass asc, last_connection desc + if newcon + timeout = 0 + goto connect - cl->status.remove = 1; - /* If this cl isn't active, don't send any DEL_HOSTs. */ + // find better nodes to connect to: in case we have less than min connections within [BACKBONE, i] and there are nodes which we are not connected to within the range + + if min <= cur < max + j = 0 + for i = BACKBONE to my.dclass + j += count(from connections where node.dclass = i) + if j < min + newcon = + first from nodes + where dclass = i and !connection and (timestamp - last_retry) > retry_timeout + order by last_connection desc + if newcon + goto connect + else + break + + + // heal partitions + + if min <= cur < max + newcon = + first from nodes + where dclass <= my.dclass and !reachable and (timestamp - last_retry) > retry_timeout + order by dclass asc, last_connection desc + if newcon + goto connect + + + // connect + +connect: + if newcon + connect newcon + + + // disconnect outgoing connections in case we have more than min connections within [BACKBONE, i] and there are nodes which we are connected to within the range [i, PORTABLE] + + if min < cur <= max + j = 0 + for i = BACKBONE to my.dclass + j += count(from connections where node.dclass = i) + if min < j + delcon = + first from nodes + where dclass >= i and outgoing_connection + order by dclass desc + if disconnect + goto disconnect + else + break + + + // disconnect connections in case we have more than enough connections + + if max < cur + delcon = + first from nodes + where outgoing_connection + order by dclass desc + goto disconnect + + // disconnect + +disconnect + if delcon + disconnect delcon + + + // next iteration + next (timeout, autoconnect) -/* FIXME: reprogram this. - if(cl->status.active) - notify_others(cl,NULL,send_del_host); -*/ - -cp - /* Find all connections that were lost because they were behind cl - (the connection that was dropped). */ - if(cl->status.meta) - for(p = conn_list; p != NULL; p = p->next) - { - if((p->nexthop == cl) && (p != cl)) - { - if(cl->status.active && p->status.active) -/* FIXME: reprogram this - notify_others(p,cl,send_del_host); -*/; - if(cl->socket) - close(cl->socket); - p->status.active = 0; - p->status.remove = 1; - } - } - - cl->status.active = 0; - - if(cl->status.outgoing) - { - signal(SIGALRM, sigalrm_handler); - seconds_till_retry = 5; - alarm(seconds_till_retry); - syslog(LOG_NOTICE, _("Trying to re-establish outgoing connection in 5 seconds")); - } -cp } -/* - Check if the other end is active. - If we have sent packets, but didn't receive any, - then possibly the other end is dead. We send a - PING request over the meta connection. If the other - end does not reply in time, we consider them dead - and close the connection. */ -int check_dead_connections(void) -{ - conn_list_t *p; - time_t now; -cp - now = time(NULL); - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.remove) - continue; - if(p->status.active && p->status.meta) - { - if(p->last_ping_time + timeout < now) - { - if(p->status.pinged && !p->status.got_pong) - { - if(debug_lvl > 1) - syslog(LOG_INFO, _("%s (%s) didn't respond to PING"), - p->name, p->hostname); - p->status.timeout = 1; - terminate_connection(p); - } - else if(p->want_ping) - { - send_ping(p); - p->last_ping_time = now; - p->status.pinged = 1; - p->status.got_pong = 0; - } - } + + +static void periodic_handler(event_loop_t *loop, void *data) { + meshlink_handle_t *mesh = loop->data; + + /* Check if there are too many contradicting ADD_EDGE and DEL_EDGE messages. + This usually only happens when another node has the same Name as this node. + If so, sleep for a short while to prevent a storm of contradicting messages. + */ + + if(mesh->contradicting_del_edge > 100 && mesh->contradicting_add_edge > 100) { + logger(mesh, MESHLINK_WARNING, "Possible node with same Name as us! Sleeping %d seconds.", mesh->sleeptime); + usleep(mesh->sleeptime * 1000000LL); + mesh->sleeptime *= 2; + + if(mesh->sleeptime < 0) { + mesh->sleeptime = 3600; + } + } else { + mesh->sleeptime /= 2; + + if(mesh->sleeptime < 10) { + mesh->sleeptime = 10; + } } - } -cp - return 0; -} -/* - accept a new tcp connect and create a - new connection -*/ -int handle_new_meta_connection() -{ - conn_list_t *ncn; - struct sockaddr client; - int nfd, len = sizeof(client); -cp - if((nfd = accept(myself->meta_socket, &client, &len)) < 0) - { - syslog(LOG_ERR, _("Accepting a new connection failed: %m")); - return -1; - } - - if(!(ncn = create_new_connection(nfd))) - { - shutdown(nfd, 2); - close(nfd); - syslog(LOG_NOTICE, _("Closed attempted connection")); - return 0; - } - - ncn->status.meta = 1; - ncn->next = conn_list; - conn_list = ncn; -cp - return 0; + mesh->contradicting_add_edge = 0; + mesh->contradicting_del_edge = 0; + + int timeout = 5; + + /* Check if we need to make or break connections. */ + + if(mesh->nodes->count > 1) { + + logger(mesh, MESHLINK_DEBUG, "--- autoconnect begin ---"); + + int retry_timeout = min(mesh->nodes->count * 5, 60); + + logger(mesh, MESHLINK_DEBUG, "* devclass = %d", mesh->devclass); + logger(mesh, MESHLINK_DEBUG, "* nodes = %d", mesh->nodes->count); + logger(mesh, MESHLINK_DEBUG, "* retry_timeout = %d", retry_timeout); + + + // connect disconnect nodes + + node_t *connect_to = NULL; + node_t *disconnect_from = NULL; + + + // get cur_connects + + unsigned int cur_connects = 0; + + for list_each(connection_t, c, mesh->connections) { + if(c->status.active) { + cur_connects += 1; + } + } + + logger(mesh, MESHLINK_DEBUG, "* cur_connects = %d", cur_connects); + logger(mesh, MESHLINK_DEBUG, "* outgoings = %d", mesh->outgoings->count); + + // get min_connects and max_connects + + assert(mesh->devclass >= 0 && mesh->devclass <= _DEV_CLASS_MAX); + + unsigned int min_connects = dev_class_traits[mesh->devclass].min_connects; + unsigned int max_connects = dev_class_traits[mesh->devclass].max_connects; + + logger(mesh, MESHLINK_DEBUG, "* min_connects = %d", min_connects); + logger(mesh, MESHLINK_DEBUG, "* max_connects = %d", max_connects); + + + // find the best one for initial connect + + if(cur_connects < min_connects) { + splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_asc_lsc_desc, NULL); + + for splay_each(node_t, n, mesh->nodes) { + logger(mesh, MESHLINK_DEBUG, "* n->devclass = %d", n->devclass); + + if(n != mesh->self && n->devclass <= mesh->devclass && !n->connection && (n->last_connect_try == 0 || (time(NULL) - n->last_connect_try) > retry_timeout)) { + splay_insert(nodes, n); + } + } + + if(nodes->head) { + logger(mesh, MESHLINK_DEBUG, "* found best one for initial connect"); + + //timeout = 0; + connect_to = (node_t *)nodes->head->data; + } else { + logger(mesh, MESHLINK_DEBUG, "* could not find node for initial connect"); + } + + splay_free_tree(nodes); + } + + + // find better nodes to connect to + + if(!connect_to && min_connects <= cur_connects && cur_connects < max_connects) { + unsigned int connects = 0; + + for(unsigned int devclass = 0; devclass <= mesh->devclass; ++devclass) { + for list_each(connection_t, c, mesh->connections) { + if(c->status.active && c->node && c->node->devclass == devclass) { + connects += 1; + } + } + + if(connects < min_connects) { + splay_tree_t *nodes = splay_alloc_tree(node_compare_lsc_desc, NULL); + + for splay_each(node_t, n, mesh->nodes) { + if(n != mesh->self && n->devclass == devclass && !n->connection && (n->last_connect_try == 0 || (time(NULL) - n->last_connect_try) > retry_timeout)) { + splay_insert(nodes, n); + } + } + + if(nodes->head) { + logger(mesh, MESHLINK_DEBUG, "* found better node"); + connect_to = (node_t *)nodes->head->data; + + splay_free_tree(nodes); + break; + } + + splay_free_tree(nodes); + } else { + break; + } + } + + if(!connect_to) { + logger(mesh, MESHLINK_DEBUG, "* could not find better nodes"); + } + } + + + // heal partitions + + if(!connect_to && min_connects <= cur_connects && cur_connects < max_connects) { + splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_asc_lsc_desc, NULL); + + for splay_each(node_t, n, mesh->nodes) { + if(n != mesh->self && n->devclass <= mesh->devclass && !n->status.reachable && (n->last_connect_try == 0 || (time(NULL) - n->last_connect_try) > retry_timeout)) { + splay_insert(nodes, n); + } + } + + if(nodes->head) { + logger(mesh, MESHLINK_DEBUG, "* try to heal partition"); + connect_to = (node_t *)nodes->head->data; + } else { + logger(mesh, MESHLINK_DEBUG, "* could not find nodes for partition healing"); + } + + splay_free_tree(nodes); + } + + + // perform connect + + if(connect_to && !connect_to->connection) { + connect_to->last_connect_try = time(NULL); + + /* check if there is already a connection attempt to this node */ + bool found = false; + + for list_each(outgoing_t, outgoing, mesh->outgoings) { + if(!strcmp(outgoing->name, connect_to->name)) { + found = true; + break; + } + } + + if(!found) { + logger(mesh, MESHLINK_DEBUG, "Autoconnecting to %s", connect_to->name); + outgoing_t *outgoing = xzalloc(sizeof(outgoing_t)); + outgoing->mesh = mesh; + outgoing->name = xstrdup(connect_to->name); + list_insert_tail(mesh->outgoings, outgoing); + setup_outgoing_connection(mesh, outgoing); + } else { + logger(mesh, MESHLINK_DEBUG, "* skip autoconnect since it is an outgoing connection already"); + } + } + + + // disconnect suboptimal outgoing connections + + if(min_connects < cur_connects /*&& cur_connects <= max_connects*/) { + unsigned int connects = 0; + + for(unsigned int devclass = 0; devclass <= mesh->devclass; ++devclass) { + for list_each(connection_t, c, mesh->connections) { + if(c->status.active && c->node && c->node->devclass == devclass) { + connects += 1; + } + } + + if(min_connects < connects) { + splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_desc, NULL); + + for list_each(connection_t, c, mesh->connections) { + if(c->outgoing && c->node && c->node->devclass >= devclass) { + splay_insert(nodes, c->node); + } + } + + if(nodes->head) { + logger(mesh, MESHLINK_DEBUG, "* disconnect suboptimal outgoing connection"); + disconnect_from = (node_t *)nodes->head->data; + } + + splay_free_tree(nodes); + break; + } + } + + if(!disconnect_from) { + logger(mesh, MESHLINK_DEBUG, "* no suboptimal outgoing connections"); + } + } + + + // disconnect connections (too many connections) + + if(!disconnect_from && max_connects < cur_connects) { + splay_tree_t *nodes = splay_alloc_tree(node_compare_devclass_desc, NULL); + + for list_each(connection_t, c, mesh->connections) { + if(c->status.active && c->node) { + splay_insert(nodes, c->node); + } + } + + if(nodes->head) { + logger(mesh, MESHLINK_DEBUG, "* disconnect connection (too many connections)"); + + //timeout = 0; + disconnect_from = (node_t *)nodes->head->data; + } else { + logger(mesh, MESHLINK_DEBUG, "* no node we want to disconnect, even though we have too many connections"); + } + + splay_free_tree(nodes); + } + + + // perform disconnect + + if(disconnect_from && disconnect_from->connection) { + logger(mesh, MESHLINK_DEBUG, "Autodisconnecting from %s", disconnect_from->connection->name); + list_delete(mesh->outgoings, disconnect_from->connection->outgoing); + disconnect_from->connection->outgoing = NULL; + terminate_connection(mesh, disconnect_from->connection, disconnect_from->connection->status.active); + } + + + // done! + + logger(mesh, MESHLINK_DEBUG, "--- autoconnect end ---"); + } + + timeout_set(&mesh->loop, data, &(struct timeval) { + timeout, rand() % 100000 + }); } -/* - check all connections to see if anything - happened on their sockets -*/ -void check_network_activity(fd_set *f) -{ - conn_list_t *p; - int x, l = sizeof(x); -cp - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.remove) - continue; - - if(p->status.dataopen) - if(FD_ISSET(p->socket, f)) - { - /* - The only thing that can happen to get us here is apparently an - error on this outgoing(!) UDP socket that isn't immediate (i.e. - something that will not trigger an error directly on send()). - I've once got here when it said `No route to host'. - */ - getsockopt(p->socket, SOL_SOCKET, SO_ERROR, &x, &l); - syslog(LOG_ERR, _("Outgoing data socket error for %s (%s): %s"), - p->name, p->hostname, strerror(x)); - terminate_connection(p); - return; - } - - if(p->status.meta) - if(FD_ISSET(p->meta_socket, f)) - if(receive_meta(p) < 0) - { - terminate_connection(p); - return; - } - } - - if(FD_ISSET(myself->socket, f)) - handle_incoming_vpn_data(); - - if(FD_ISSET(myself->meta_socket, f)) - handle_new_meta_connection(); -cp +void handle_meta_connection_data(meshlink_handle_t *mesh, connection_t *c) { + if(!receive_meta(mesh, c)) { + terminate_connection(mesh, c, c->status.active); + return; + } } -/* - read, encrypt and send data that is - available through the ethertap device -*/ -void handle_tap_input(void) -{ - vpn_packet_t vp; - ip_t from, to; - int ether_type, lenin; -cp - memset(&vp, 0, sizeof(vp)); - if((lenin = read(tap_fd, &vp, MTU)) <= 0) - { - syslog(LOG_ERR, _("Error while reading from tapdevice: %m")); - return; - } - - total_tap_in += lenin; - - ether_type = ntohs(*((unsigned short*)(&vp.data[12]))); - if(ether_type != 0x0800) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("Non-IP ethernet frame %04x from %02x:%02x:%02x:%02x:%02x:%02x"), ether_type, MAC_ADDR_V(vp.data[6])); - return; - } - - if(lenin < 32) - { - if(debug_lvl > 3) - syslog(LOG_INFO, _("Dropping short packet from %02x:%02x:%02x:%02x:%02x:%02x"), MAC_ADDR_V(vp.data[6])); - return; - } - - from = ntohl(*((unsigned long*)(&vp.data[26]))); - to = ntohl(*((unsigned long*)(&vp.data[30]))); - - vp.len = (length_t)lenin - 2; - - strip_mac_addresses(&vp); - - send_packet(to, &vp); -cp +void retry(meshlink_handle_t *mesh) { + /* Reset the reconnection timers for all outgoing connections */ + for list_each(outgoing_t, outgoing, mesh->outgoings) { + outgoing->timeout = 0; + + if(outgoing->ev.cb) + timeout_set(&mesh->loop, &outgoing->ev, &(struct timeval) { + 0, 0 + }); + } + + /* Check for outgoing connections that are in progress, and reset their ping timers */ + for list_each(connection_t, c, mesh->connections) { + if(c->outgoing && !c->node) { + c->last_ping_time = 0; + } + } + + /* Kick the ping timeout handler */ + timeout_set(&mesh->loop, &mesh->pingtimer, &(struct timeval) { + 0, 0 + }); } /* this is where it all happens... */ -void main_loop(void) -{ - fd_set fset; - struct timeval tv; - int r; - time_t last_ping_check; -cp - last_ping_check = time(NULL); - - for(;;) - { - tv.tv_sec = timeout; - tv.tv_usec = 0; - - prune_conn_list(); - build_fdset(&fset); - - if((r = select(FD_SETSIZE, &fset, NULL, NULL, &tv)) < 0) - { - if(errno != EINTR) /* because of alarm */ - { - syslog(LOG_ERR, _("Error while waiting for input: %m")); - return; - } - } - - if(sighup) - { - sighup = 0; -/* FIXME: reprogram this. - if(debug_lvl > 1) - syslog(LOG_INFO, _("Rereading configuration file")); - close_network_connections(); - clear_config(); - if(read_config_file(&config, configfilename)) - { - syslog(LOG_ERR, _("Unable to reread configuration file, exiting")); - exit(0); - } - sleep(5); - setup_network_connections(); -*/ - continue; - } - - if(last_ping_check + timeout < time(NULL)) - /* Let's check if everybody is still alive */ - { - check_dead_connections(); - last_ping_check = time(NULL); +int main_loop(meshlink_handle_t *mesh) { + timeout_add(&mesh->loop, &mesh->pingtimer, timeout_handler, &mesh->pingtimer, &(struct timeval) { + mesh->pingtimeout, rand() % 100000 + }); + timeout_add(&mesh->loop, &mesh->periodictimer, periodic_handler, &mesh->periodictimer, &(struct timeval) { + 0, 0 + }); + + //Add signal handler + mesh->datafromapp.signum = 0; + signal_add(&(mesh->loop), &(mesh->datafromapp), (signal_cb_t)meshlink_send_from_queue, mesh, mesh->datafromapp.signum); + + if(!event_loop_run(&(mesh->loop), &(mesh->mesh_mutex))) { + logger(mesh, MESHLINK_ERROR, "Error while waiting for input: %s", strerror(errno)); + return 1; } - if(r > 0) - { - check_network_activity(&fset); + timeout_del(&mesh->loop, &mesh->periodictimer); + timeout_del(&mesh->loop, &mesh->pingtimer); - /* local tap data */ - if(FD_ISSET(tap_fd, &fset)) - handle_tap_input(); - } - } -cp + return 0; }