X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=b6007b4871a4781341ea51ad1038df735640e797;hp=ec28d6a9f967e0d98400f3fc67e207d1386db312;hb=e20e143f1e99bdc0a7d92e97da1bd0dc40e8a83b;hpb=b50523dc44bbb32f03d24573e195c071cbff3fc4 diff --git a/src/net.c b/src/net.c index ec28d6a9..b6007b48 100644 --- a/src/net.c +++ b/src/net.c @@ -1,6 +1,6 @@ /* net.c -- most of the network code - Copyright (C) 1998,99 Ivo Timmermans + Copyright (C) 1998,1999,2000 Ivo Timmermans 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 @@ -51,8 +51,6 @@ int total_tap_out = 0; int total_socket_in = 0; int total_socket_out = 0; -time_t last_ping_time = 0; - /* The global list of existing connections */ conn_list_t *conn_list = NULL; conn_list_t *myself = NULL; @@ -63,10 +61,11 @@ conn_list_t *myself = NULL; void strip_mac_addresses(vpn_packet_t *p) { unsigned char tmp[MAXSIZE]; - +cp memcpy(tmp, p->data, p->len); p->len -= 12; memcpy(p->data, &tmp[12], p->len); +cp } /* @@ -75,7 +74,7 @@ void strip_mac_addresses(vpn_packet_t *p) void add_mac_addresses(vpn_packet_t *p) { unsigned char tmp[MAXSIZE]; - +cp memcpy(&tmp[12], p->data, p->len); p->len += 12; tmp[0] = tmp[6] = 0xfe; @@ -83,20 +82,23 @@ void add_mac_addresses(vpn_packet_t *p) *((ip_t*)(&tmp[2])) = (ip_t)(htonl(myself->vpn_ip)); *((ip_t*)(&tmp[8])) = *((ip_t*)(&tmp[26])); memcpy(p->data, &tmp[0], p->len); +cp } int xsend(conn_list_t *cl, void *packet) { int r; real_packet_t rp; - +cp do_encrypt((vpn_packet_t*)packet, &rp, cl->key); - rp.from = myself->vpn_ip; + rp.from = htonl(myself->vpn_ip); + rp.data.len = htons(rp.data.len); + rp.len = htons(rp.len); if(debug_lvl > 3) - syslog(LOG_ERR, "Sent %d bytes to %lx", rp.len, cl->vpn_ip); + syslog(LOG_ERR, "Sent %d bytes to %lx", ntohs(rp.len), cl->vpn_ip); - if((r = send(cl->socket, (char*)&rp, rp.len, 0)) < 0) + if((r = send(cl->socket, (char*)&rp, ntohs(rp.len), 0)) < 0) { syslog(LOG_ERR, "Error sending data: %m"); return -1; @@ -104,42 +106,27 @@ int xsend(conn_list_t *cl, void *packet) total_socket_out += r; + cl->want_ping = 1; +cp return 0; } -/* - write as many bytes as possible to the tap - device, possibly in multiple turns. -*/ -int write_n(int fd, void *buf, size_t len) -{ - int r, done = 0; - - do - { - if((r = write(fd, buf, len)) < 0) - return -1; - len -= r; - buf += r; - done += r; - } while(len > 0); - - return done; -} - int xrecv(conn_list_t *cl, void *packet) { vpn_packet_t vp; int lenin; - +cp do_decrypt((real_packet_t*)packet, &vp, cl->key); add_mac_addresses(&vp); - if((lenin = write_n(tap_fd, &vp, vp.len + 2)) < 0) + if((lenin = write(tap_fd, &vp, vp.len + sizeof(vp.len))) < 0) syslog(LOG_ERR, "Can't write to tap device: %m"); else total_tap_out += lenin; + cl->want_ping = 0; + cl->last_ping_time = time(NULL); +cp return 0; } @@ -149,29 +136,73 @@ int xrecv(conn_list_t *cl, void *packet) */ void add_queue(packet_queue_t **q, void *packet, size_t s) { - queue_element_t *e, *p; - + queue_element_t *e; +cp if(debug_lvl > 3) syslog(LOG_DEBUG, "packet to queue: %d", s); - e = xmalloc(sizeof(queue_element_t)); + e = xmalloc(sizeof(*e)); e->packet = xmalloc(s); memcpy(e->packet, packet, s); + if(!*q) { - *q = xmalloc(sizeof(packet_queue_t)); + *q = xmalloc(sizeof(**q)); (*q)->head = (*q)->tail = NULL; } - e->next = NULL; + e->next = NULL; /* We insert at the tail */ - if((*q)->tail != NULL) - (*q)->tail->next = e; + 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((*q)->head == NULL) - (*q)->head = e; +/* 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 } /* @@ -179,38 +210,24 @@ void add_queue(packet_queue_t **q, void *packet, size_t s) each packet, and removing it when that returned a zero exit code */ -void flush_queue(conn_list_t *cl, packet_queue_t *pq, +void flush_queue(conn_list_t *cl, packet_queue_t **pq, int (*function)(conn_list_t*,void*)) { - queue_element_t *p, *prev = NULL, *next = NULL; - - for(p = pq->head; p != NULL; ) + queue_element_t *p, *next = NULL; +cp + for(p = (*pq)->head; p != NULL; ) { next = p->next; -cp if(!function(cl, p->packet)) - { - if(prev) - prev->next = next; - else - pq->head = next; - -cp - free(p->packet); -cp - free(p); -cp - } - else - prev = p; -cp - + del_queue(pq, p); + p = next; } if(debug_lvl > 3) syslog(LOG_DEBUG, "queue flushed"); +cp } /* @@ -226,16 +243,15 @@ cp if(debug_lvl > 1) syslog(LOG_DEBUG, "Flushing send queue for " IP_ADDR_S, IP_ADDR_V(cl->vpn_ip)); - flush_queue(cl, cl->sq, xsend); + flush_queue(cl, &(cl->sq), xsend); } -cp if(cl->rq) { if(debug_lvl > 1) syslog(LOG_DEBUG, "Flushing receive queue for " IP_ADDR_S, IP_ADDR_V(cl->vpn_ip)); - flush_queue(cl, cl->rq, xrecv); + flush_queue(cl, &(cl->rq), xrecv); } cp } @@ -246,7 +262,7 @@ cp int send_packet(ip_t to, vpn_packet_t *packet) { conn_list_t *cl; - +cp if((cl = lookup_conn(to)) == NULL) { if(debug_lvl > 2) @@ -263,25 +279,21 @@ int send_packet(ip_t to, vpn_packet_t *packet) } } -cp if(my_key_expiry <= time(NULL)) regenerate_keys(); -cp if(!cl->status.dataopen) if(setup_vpn_connection(cl) < 0) return -1; -cp if(!cl->status.validkey) { add_queue(&(cl->sq), packet, packet->len + 2); if(!cl->status.waitingforkey) - send_key_request(to); + send_key_request(cl->vpn_ip); /* Keys should be sent to the host running the tincd */ return 0; } -cp if(!cl->status.active) { add_queue(&(cl->sq), packet, packet->len + 2); @@ -295,21 +307,6 @@ cp return xsend(cl, packet); } -int send_broadcast(conn_list_t *cl, vpn_packet_t *packet) -{ - conn_list_t *p; - - for(p = cl; p != NULL; p = p->next) - if(send_packet(p->real_ip, packet) < 0) - { - syslog(LOG_ERR, "Could not send a broadcast packet to %08lx (%08lx): %m", - p->vpn_ip, p->real_ip); - break; /* FIXME: should retry later, and send a ping over the metaconnection. */ - } - - return 0; -} - /* open the local ethertap device */ @@ -318,7 +315,7 @@ int setup_tap_fd(void) int nfd; const char *tapfname; config_t const *cfg; - +cp if((cfg = get_config_val(tapdevice)) == NULL) tapfname = "/dev/tap0"; else @@ -331,6 +328,7 @@ int setup_tap_fd(void) } tap_fd = nfd; +cp return 0; } @@ -343,7 +341,7 @@ int setup_listen_meta_socket(int port) int nfd, flags; struct sockaddr_in a; const int one = 1; - +cp if((nfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) { syslog(LOG_ERR, "Creating metasocket failed: %m"); @@ -379,7 +377,7 @@ int setup_listen_meta_socket(int port) syslog(LOG_ERR, "listen: %m"); return -1; } - +cp return nfd; } @@ -392,7 +390,7 @@ 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"); @@ -422,7 +420,7 @@ int setup_vpn_in_socket(int port) syslog(LOG_ERR, "Can't bind to port %hd/udp: %m", port); return -1; } - +cp return nfd; } @@ -434,7 +432,7 @@ int setup_outgoing_meta_socket(conn_list_t *cl) int flags; struct sockaddr_in a; config_t const *cfg; - +cp if((cfg = get_config_val(upstreamport)) == NULL) cl->port = 655; else @@ -467,7 +465,7 @@ int setup_outgoing_meta_socket(conn_list_t *cl) cl->hostname = hostlookup(htonl(cl->real_ip)); syslog(LOG_INFO, "Connected to %s:%hd" , cl->hostname, cl->port); - +cp return 0; } @@ -481,7 +479,7 @@ int setup_outgoing_meta_socket(conn_list_t *cl) int setup_outgoing_connection(ip_t ip) { conn_list_t *ncn; - +cp ncn = new_conn_list(); ncn->real_ip = ip; @@ -496,7 +494,7 @@ int setup_outgoing_connection(ip_t ip) ncn->status.outgoing = 1; ncn->next = conn_list; conn_list = ncn; - +cp return 0; } @@ -506,7 +504,7 @@ int setup_outgoing_connection(ip_t ip) int setup_myself(void) { config_t const *cfg; - +cp myself = new_conn_list(); if(!(cfg = get_config_val(myvpnip))) @@ -539,7 +537,7 @@ int setup_myself(void) myself->status.active = 1; syslog(LOG_NOTICE, "Ready: listening on port %d.", myself->port); - +cp return 0; } @@ -549,9 +547,9 @@ int setup_myself(void) int setup_network_connections(void) { config_t const *cfg; - +cp if((cfg = get_config_val(pingtimeout)) == NULL) - timeout = 10; + timeout = 5; else timeout = cfg->data.val; @@ -567,7 +565,7 @@ int setup_network_connections(void) if(setup_outgoing_connection(cfg->data.ip->ip)) return -1; - +cp return 0; } @@ -576,7 +574,7 @@ sigalrm_handler(int a) { config_t const *cfg; static int seconds_till_retry; - +cp cfg = get_config_val(upstreamip); if(!setup_outgoing_connection(cfg->data.ip->ip)) @@ -592,6 +590,7 @@ sigalrm_handler(int a) syslog(LOG_ERR, "Still failed to connect to other. Will retry in %d seconds.", seconds_till_retry); } +cp } /* @@ -600,7 +599,7 @@ sigalrm_handler(int a) void close_network_connections(void) { conn_list_t *p; - +cp for(p = conn_list; p != NULL; p = p->next) { if(p->status.dataopen) @@ -627,6 +626,7 @@ void close_network_connections(void) destroy_conn_list(); syslog(LOG_NOTICE, "Terminating."); +cp return; } @@ -637,7 +637,7 @@ int setup_vpn_connection(conn_list_t *cl) { int nfd, flags; struct sockaddr_in a; - +cp if(debug_lvl > 1) syslog(LOG_DEBUG, "Opening UDP socket to " IP_ADDR_S, IP_ADDR_V(cl->real_ip)); @@ -668,7 +668,7 @@ int setup_vpn_connection(conn_list_t *cl) cl->socket = nfd; cl->status.dataopen = 1; - +cp return 0; } @@ -681,7 +681,7 @@ 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) @@ -694,7 +694,10 @@ conn_list_t *create_new_connection(int sfd) p->real_ip = ntohl(ci.sin_addr.s_addr); p->meta_socket = sfd; p->status.meta = 1; - + p->buflen = 0; + p->last_ping_time = time(NULL); + p->want_ping = 0; + syslog(LOG_NOTICE, "Connection from %s:%d", p->hostname, htons(ci.sin_port)); if(send_basic_info(p) < 0) @@ -702,7 +705,7 @@ conn_list_t *create_new_connection(int sfd) free(p); return NULL; } - +cp return p; } @@ -712,7 +715,7 @@ conn_list_t *create_new_connection(int sfd) void build_fdset(fd_set *fs) { conn_list_t *p; - +cp FD_ZERO(fs); for(p = conn_list; p != NULL; p = p->next) @@ -726,6 +729,7 @@ void build_fdset(fd_set *fs) FD_SET(myself->meta_socket, fs); FD_SET(myself->socket, fs); FD_SET(tap_fd, fs); +cp } /* @@ -739,7 +743,7 @@ int handle_incoming_vpn_data(conn_list_t *cl) int lenin; int x, l = sizeof(x); conn_list_t *f; - +cp if(getsockopt(cl->socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0) { syslog(LOG_ERR, "This is a bug: %s:%d: %d:%m", __FILE__, __LINE__, cl->socket); @@ -759,10 +763,15 @@ int handle_incoming_vpn_data(conn_list_t *cl) return -1; } total_socket_in += lenin; + + rp.data.len = ntohs(rp.data.len); + rp.len = ntohs(rp.len); + rp.from = ntohl(rp.from); + if(rp.len >= 0) { f = lookup_conn(rp.from); - if(debug_lvl > 2) + if(debug_lvl > 3) syslog(LOG_DEBUG, "packet from " IP_ADDR_S " (len %d)", IP_ADDR_V(rp.from), rp.len); if(!f) @@ -784,7 +793,7 @@ int handle_incoming_vpn_data(conn_list_t *cl) if(my_key_expiry <= time(NULL)) regenerate_keys(); } - +cp return 0; } @@ -794,6 +803,7 @@ int handle_incoming_vpn_data(conn_list_t *cl) */ void terminate_connection(conn_list_t *cl) { +cp if(cl->status.remove) return; @@ -817,58 +827,48 @@ void terminate_connection(conn_list_t *cl) } cl->status.remove = 1; +cp } /* - send out a ping request to all active - connections -*/ -int send_broadcast_ping(void) -{ - conn_list_t *p; - - for(p = conn_list; p != NULL; p = p->next) - { - if(p->status.remove) - continue; - if(p->status.active && p->status.meta) - { - if(send_ping(p)) - terminate_connection(p); - else - { - p->status.pinged = 1; - p->status.got_pong = 0; - } - } - } - - last_ping_time = time(NULL); - - return 0; -} - -/* - end all connections that did not respond - to the ping probe in time + 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 && p->status.pinged && !p->status.got_pong) + if(p->status.active && p->status.meta) { - syslog(LOG_INFO, "%s (" IP_ADDR_S ") didn't respond to ping", - p->hostname, IP_ADDR_V(p->vpn_ip)); - p->status.timeout = 1; - terminate_connection(p); + if(p->last_ping_time + timeout < now) + if(p->status.pinged && !p->status.got_pong) + { + syslog(LOG_INFO, "%s (" IP_ADDR_S ") didn't respond to ping", + p->hostname, IP_ADDR_V(p->vpn_ip)); + 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.get_pong = 0; + } + } } } - +cp return 0; } @@ -880,8 +880,8 @@ int handle_new_meta_connection(conn_list_t *cl) { conn_list_t *ncn; struct sockaddr client; - int nfd, len = sizeof(struct sockaddr); - + int nfd, len = sizeof(client); +cp if((nfd = accept(cl->meta_socket, &client, &len)) < 0) { syslog(LOG_ERR, "Accepting a new connection failed: %m"); @@ -899,7 +899,7 @@ int handle_new_meta_connection(conn_list_t *cl) ncn->status.meta = 1; ncn->next = conn_list; conn_list = ncn; - +cp return 0; } @@ -908,10 +908,10 @@ int handle_new_meta_connection(conn_list_t *cl) */ int handle_incoming_meta_data(conn_list_t *cl) { - int x, l = sizeof(x), lenin; - unsigned char tmp[1600]; - int request; - + int x, l = sizeof(x); + int request, oldlen, i; + int lenin = 0; +cp if(getsockopt(cl->meta_socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0) { syslog(LOG_ERR, "This is a bug: %s:%d: %d:%m", __FILE__, __LINE__, cl->meta_socket); @@ -923,23 +923,70 @@ int handle_incoming_meta_data(conn_list_t *cl) return -1; } - if((lenin = recv(cl->meta_socket, &tmp, sizeof(tmp), 0)) <= 0) + if(cl->buflen >= MAXBUFSIZE) { - syslog(LOG_ERR, "Receive failed: %m"); + syslog(LOG_ERR, "Metadata read buffer full! Discarding contents."); + cl->buflen = 0; + } + + lenin = read(cl->meta_socket, cl->buffer, MAXBUFSIZE-cl->buflen); + + if(lenin<=0) + { + syslog(LOG_ERR, "Metadata socket read error: %m"); return -1; } - request = (int)(tmp[0]); + oldlen = cl->buflen; + cl->buflen += lenin; - if(debug_lvl > 3) - syslog(LOG_DEBUG, "got request %d", request); + for(;;) + { + cl->reqlen = 0; - if(request_handlers[request] == NULL) - syslog(LOG_ERR, "Unknown request %d.", request); - else - if(request_handlers[request](cl, tmp, lenin) < 0) - return -1; - + for(i = oldlen; i < cl->buflen; i++) + { + if(cl->buffer[i] == '\n') + { + cl->buffer[i] = 0; /* replace end-of-line by end-of-string so we can use sscanf */ + cl->reqlen = i + 1; + break; + } + } + + if(cl->reqlen) + { + if(sscanf(cl->buffer, "%d", &request) == 1) + { + if(request_handlers[request] == NULL) + { + syslog(LOG_ERR, "Unknown request: %s", cl->buffer); + return 0; + } + + if(debug_lvl > 3) + syslog(LOG_DEBUG, "Got request: %s", cl->buffer); + + request_handlers[request](cl); + } + else + { + syslog(LOG_ERR, "Bogus data received: %s", cl->buffer); + } + + cl->buflen -= cl->reqlen; + memmove(cl->buffer, cl->buffer + cl->reqlen, cl->buflen); + oldlen = 0; + } + else + { + break; + } + } + + cl->last_ping_time = time(NULL); + cl->want_ping = 0; +cp return 0; } @@ -951,13 +998,13 @@ 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; -cp - if(p->status.active) + + if(p->status.dataopen) if(FD_ISSET(p->socket, f)) { /* @@ -971,7 +1018,7 @@ cp terminate_connection(p); return; } -cp + if(p->status.meta) if(FD_ISSET(p->meta_socket, f)) if(handle_incoming_meta_data(p) < 0) @@ -979,13 +1026,11 @@ cp terminate_connection(p); return; } -cp } -cp if(FD_ISSET(myself->socket, f)) handle_incoming_vpn_data(myself); -cp + if(FD_ISSET(myself->meta_socket, f)) handle_new_meta_connection(myself); cp @@ -1000,7 +1045,7 @@ 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) { @@ -1029,42 +1074,40 @@ void handle_tap_input(void) from = ntohl(*((unsigned long*)(&vp.data[26]))); to = ntohl(*((unsigned long*)(&vp.data[30]))); - if(debug_lvl > 2) + if(debug_lvl > 3) syslog(LOG_DEBUG, "An IP packet (%04x) for " IP_ADDR_S " from " IP_ADDR_S, ether_type, IP_ADDR_V(to), IP_ADDR_V(from)); - if(debug_lvl > 3) + if(debug_lvl > 4) syslog(LOG_DEBUG, MAC_ADDR_S " to " MAC_ADDR_S, MAC_ADDR_V(vp.data[0]), MAC_ADDR_V(vp.data[6])); vp.len = (length_t)lenin - 2; -cp + strip_mac_addresses(&vp); -cp + send_packet(to, &vp); cp } /* - this is where it al happens... + this is where it all happens... */ void main_loop(void) { fd_set fset; struct timeval tv; int r; - - last_ping_time = time(NULL); + time_t last_ping_check; +cp + last_ping_check = time(NULL); for(;;) { tv.tv_sec = timeout; tv.tv_usec = 0; -cp prune_conn_list(); -cp build_fdset(&fset); -cp if((r = select(FD_SETSIZE, &fset, NULL, NULL, &tv)) < 0) { @@ -1073,23 +1116,20 @@ cp syslog(LOG_ERR, "Error while waiting for input: %m"); return; } -cp - if(r == 0 || last_ping_time + timeout < time(NULL)) - /* Timeout... hm... something might be wrong. */ + if(last_ping_check + timeout < time(NULL)) + /* Let's check if everybody is still alive */ { check_dead_connections(); - send_broadcast_ping(); + last_ping_check = time(NULL); continue; } -cp check_network_activity(&fset); -cp /* local tap data */ if(FD_ISSET(tap_fd, &fset)) handle_tap_input(); -cp } +cp }