X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=f36538e382899ca4f4d3a27ff4267899fb64f185;hp=f1a9e49bfdcea01e4293ab351d53d9b74364ee99;hb=2a3e343c7228d5f07176e4b404d895c7adc5bdf9;hpb=28cc30159565a7eda4f66215a5994d84b46b47ad diff --git a/src/protocol.c b/src/protocol.c index f1a9e49b..f36538e3 100644 --- a/src/protocol.c +++ b/src/protocol.c @@ -1,7 +1,7 @@ /* - protocol.c -- handle the meta-protocol - Copyright (C) 1999,2000 Ivo Timmermans , - 2000 Guus Sliepen + protocol.c -- handle the meta-protocol, basic functions + Copyright (C) 1999-2005 Ivo Timmermans, + 2000-2012 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 @@ -13,1113 +13,228 @@ 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: protocol.c,v 1.28.4.25 2000/09/10 15:18:03 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 "system.h" #include "conf.h" -#include "encr.h" -#include "net.h" -#include "netutl.h" +#include "connection.h" +#include "logger.h" +#include "meta.h" #include "protocol.h" +#include "utils.h" +#include "xalloc.h" -#include "system.h" - -/* Generic outgoing request routine - takes care of logging and error detection as well */ - -int send_request(conn_list_t *cl, const char *format, int request, /*args*/ ...) -{ - va_list args; - char *buffer = NULL; -cp - if(debug_lvl >= DEBUG_PROTOCOL) - syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), requestname[request], cl->id, cl->hostname); - - va_start(args, format); - len = vasprintf(&buffer, format, args); - va_end(args); - - if(len < 0 || !buffer) - { - syslog(LOG_ERR, _("Error during vasprintf(): %m")); - return -1; - } - - if(debug_lvl >= DEBUG_META) - syslog(LOG_DEBUG, _("Sending meta data to %s (%s): %s"), cl->id, cl->hostname, buffer); - - if(cl->status.encryptout) - { - /* FIXME: Do encryption */ - } - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Sending meta data failed: %m")); - return -1; - } -cp -} - -/* Connection protocol: - - Client Server - send_id(*) - send_challenge - send_chal_reply(*) - send_id - send_challenge - send_chal_reply - send_ack - send_ack - - (*) Unencrypted. -*/ - -int send_id(conn_list_t *cl) -{ -cp - return send_request(cl, "%d %s %d-%d %s", ID, myself->id, myself->min_version, myself->max_version, opt2str(myself->options)); -} - -int id_h(conn_list_t *cl) -{ - conn_list_t *old; - char *options; -cp - if(sscanf(cl->buffer, "%*d %as %d-%d %as", &cl->id, &cl->min_version, &cl->max_version, &options) != 4) - { - syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname); - return -1; - } - - /* Check if version ranges overlap */ - - if((cl->min_version > myself->max_version) || (cl->max_version < myself_min_version) || (cl->min_version > cl->max_version)) - { - syslog(LOG_ERR, _("Peer %s uses incompatible version (%d-%d)"), cl->hostname, cl->min_version, cl->max_version); - return -1; - } - - /* Check if option string is valid */ - - if(str2opt(options) == -1) - { - syslog(LOG_ERR, _("Peer %s uses invalid option string"), cl->hostname); - return -1; - } - - /* Check if identity is a valid name */ - - if(!check_id(cl->id)) - { - syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname); - return -1; - } - - /* Load information about peer */ - - if(!read_id(cl)) - { - syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->id); - return -1; - } - - - /* First check if the host we connected to is already in our - connection list. If so, we are probably making a loop, which - is not desirable. - */ - - if(cl->status.outgoing) - { - if((old=lookup_id(cl->id))) - { - if(debug_lvl > DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->id, cl->hostname); - cl->status.outgoing = 0; - old->status.outgoing = 1; - terminate_connection(cl); - return 0; - } - } - - /* Since we know the identity now, we can encrypt the meta channel */ - - cl->status.encryptout = 1; - - /* Send a challenge to verify the identity */ - - cl->allow_request = CHAL_REPLY; -cp - return send_challenge(cl); -} - -int send_challenge(conn_list_t *cl) -{ - char *buffer; - int keylength; - int x; -cp - if(cl->chal_hash) - free(cl->chal_hash); - - /* Allocate buffers for the challenge and the hash */ - - cl->chal_hash = xmalloc(SHA_DIGEST_LEN); - keylength = BN_num_bytes(cl->metakey.n); - buffer = xmalloc(keylength*2); - - /* Copy random data and the public key to the buffer */ - - RAND_bytes(buffer, keylength); - BN_bn2bin(cl->metakey.n, buffer+keylength); - - /* Calculate the hash from that */ - - SHA1(buffer, keylength*2, cl->chal_hash); - - /* Convert the random data to a hexadecimal formatted string */ - - bin2hex(buffer,buffer,keylength); - buffer[keylength*2] = '\0'; - - /* Send the challenge */ - - cl->allow_request = CHAL_REPLY; - x = send_request(cl, "%d %s", CHALLENGE, buffer); - free(buffer); -cp - return x; -} - -int challenge_h(conn_list_t *cl) -{ - char *challenge; -cp - if(sscanf(cl->buffer, "%*d %as", &cl->id, &challenge) != 1) - { - syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->id, cl->hostname); - return -1; - } - - /* Rest is done by send_chal_reply() */ - - x = send_chal_reply(cl, challenge); - free(challenge); -cp - return x; -} - -int send_chal_reply(conn_list_t *cl, char *challenge) -{ - char *buffer; - int keylength; - char *hash; - int x; -cp - keylength = BN_num_bytes(myself->meyakey.n); - - /* Check if the length of the challenge is all right */ - - if(strlen(challenge) != keylength*2) - { - syslog(LOG_ERROR, _("Intruder: wrong challenge length from %s (%s)"), cl->id, cl->hostname); - return -1; - } - - /* Allocate buffers for the challenge and the hash */ - - buffer = xmalloc(keylength*2); - hash = xmalloc(SHA_DIGEST_LEN*2+1); - - /* Copy the incoming random data and our public key to the buffer */ - - hex2bin(challenge, buffer, keylength); - BN_bn2bin(myself->metakey.n, buffer+keylength); - - /* Calculate the hash from that */ - - SHA1(buffer, keylength*2, hash); - free(buffer); - - /* Convert the hash to a hexadecimal formatted string */ - - bin2hex(hash,hash,SHA_DIGEST_LEN); - hash[SHA_DIGEST_LEN*2] = '\0'; - - /* Send the reply */ - - if(cl->status.outgoing) - cl->allow_resuest = ID; - else - cl->allow_request = ACK; - - x = send_request(cl, "%d %s", CHAL_REPLY, hash); - free(hash); -cp - return x; -} - -int chal_reply_h(conn_list_t *cl) -{ - char *hash; -cp - if(sscanf(cl->buffer, "%*d %as", &cl->id, &hash) != 2) - { - syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->id, cl->hostname); - return -1; - } - - /* Check if the length of the hash is all right */ - - if(strlen(hash) != SHA_DIGEST_LEN*2) - { - syslog(LOG_ERROR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->id, cl->hostname); - return -1; - } - - /* Convert the hash to binary format */ - - hex2bin(hash, hash, SHA_DIGEST_LEN); - - /* Verify the incoming hash with the calculated hash */ - - if{!memcmp(hash, cl->chal_hash, SHA_DIGEST_LEN)} - { - syslog(LOG_ERROR, _("Intruder: wrong challenge reply from %s (%s)"), cl->id, cl->hostname); - return -1; - } - - /* Identity has now been positively verified. - If we are accepting this new connection, then send our identity, - if we are making this connecting, acknowledge. - */ - - free(hash); - free(cl->chal_hash); - -cp - if(cl->status.outgoing) - { - cl->allow_request = ACK; - return send_ack(cl); - } - else - { - cl->allow_request = CHALLENGE; - return send_id(cl); - } -} - -int send_ack(conn_list_t *cl) -{ -cp - return send_request(cl, "%d", ACK); -} - -int ack_h(conn_list_t *cl) -{ -cp - /* Okay, before we active the connection, we check if there is another entry - in the connection list with the same vpn_ip. If so, it presumably is an - old connection that has timed out but we don't know it yet. - */ - - while((old = lookup_conn(cl->vpn_ip))) - { - if(debug_lvl > 1) - syslog(LOG_NOTICE, _("Removing old entry for %s at %s in favour of new connection from %s"), - cl->vpn_hostname, old->real_hostname, cl->real_hostname); - old->status.active = 0; - terminate_connection(old); - } - - /* Activate this connection */ - - cl->allow_request = ALL; - cl->status.active = 1; - - if(debug_lvl > DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->id, cl->hostname); - - /* Exchange information about other tinc daemons */ - - notify_others(cl, NULL, send_add_host); - notify_one(cl); - - upstreamindex = 0; - -cp - if(cl->status.outgoing) - return 0; - else - return send_ack(cl); -} - -/* Address and subnet information exchange */ - -/* New and closed connections notification */ - -/* Status and error notification routines */ - -int send_status(conn_list_t *cl, int statusno, char *statusstring) -{ -cp - return send_request(cl, "%d %d %s", STATUS, statusno, statusstring); -} - -int send_error(conn_list_t *cl, int errno, char *errstring) -{ -cp - return send_request(cl, "%d %d %s", ERROR, errno, errstring); -} - -/* Old routines */ - - -int send_termreq(conn_list_t *cl) -{ -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending TERMREQ to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", TERMREQ, myself->vpn_ip); - - if(write(cl->meta_socket, buffer, buflen) < 0) - { - if(debug_lvl > 1) - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -int send_timeout(conn_list_t *cl) -{ -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending TIMEOUT to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", PINGTIMEOUT, myself->vpn_ip); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -int send_del_host(conn_list_t *cl, conn_list_t *new_host) -{ -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending DEL_HOST for %s (%s) to %s (%s)"), - new_host->vpn_hostname, new_host->real_hostname, cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", DEL_HOST, new_host->vpn_ip); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -int send_tcppacket(conn_list_t *cl, void *data, int len) -{ -cp - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Sending PACKET to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %d\n", PACKET, len); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } - - if((write(cl->meta_socket, data, len)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -int send_ping(conn_list_t *cl) -{ -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending PING to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", PING); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -int send_pong(conn_list_t *cl) -{ -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending PONG to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", PONG); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -int send_add_host(conn_list_t *cl, conn_list_t *new_host) -{ - ip_t real_ip; - int flags; - char *hostname; -cp - real_ip = new_host->real_ip; - hostname = new_host->real_hostname; - flags = new_host->flags; - - /* If we need to propagate information about a new host that wants us to export - * it's indirectdata flag, we set the INDIRECTDATA flag and unset the EXPORT... - * flag, and set it's real_ip to our vpn_ip, so that net.c send_packet() will - * work correctly. - */ - - if(flags & EXPORTINDIRECTDATA) - { - flags &= ~EXPORTINDIRECTDATA; - flags |= INDIRECTDATA; - real_ip = myself->vpn_ip; - hostname = myself->real_hostname; - } +bool tunnelserver = false; +bool strictsubnets = false; - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending ADD_HOST for %s (%s) to %s (%s)"), - new_host->vpn_hostname, hostname, cl->vpn_hostname, cl->real_hostname); +/* Jumptable for the request handlers */ - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx/%lx:%x %d\n", ADD_HOST, real_ip, new_host->vpn_ip, new_host->vpn_mask, new_host->port, flags); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -int send_key_changed(conn_list_t *cl, conn_list_t *src) -{ -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending KEY_CHANGED origin %s to %s (%s)"), - src->vpn_hostname, cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", KEY_CHANGED, src->vpn_ip); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -void send_key_changed_all(void) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - if(p->status.meta && p->status.active) - send_key_changed(p, myself); -cp -} - - -int send_key_request(ip_t to) -{ - conn_list_t *fw; -cp - fw = lookup_conn(to); - if(!fw) - { - syslog(LOG_ERR, _("Attempting to send REQ_KEY to %d.%d.%d.%d, which does not exist?"), - IP_ADDR_V(to)); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending REQ_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx\n", REQ_KEY, to, myself->vpn_ip); - - if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } - fw->status.waitingforkey = 1; -cp - return 0; -} - -int send_key_answer(conn_list_t *cl, ip_t to) -{ - conn_list_t *fw; -cp - - fw = lookup_conn(to); - - if(!fw) - { - syslog(LOG_ERR, _("Attempting to send ANS_KEY to %d.%d.%d.%d, which does not exist?"), - IP_ADDR_V(to)); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending ANS_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx %d %s\n", ANS_KEY, to, myself->vpn_ip, my_key_expiry, my_public_key_base36); - - if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -/* - notify all my direct connections of a new host - that was added to the vpn, with the exception - of the source of the announcement. -*/ -int notify_others(conn_list_t *new, conn_list_t *source, - int (*function)(conn_list_t*, conn_list_t*)) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - if(p != new && p != source && p->status.meta && p->status.active) - function(p, new); -cp - return 0; -} - -/* - notify one connection of everything - i have connected -*/ -int notify_one(conn_list_t *new) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - if(p != new && p->status.active) - send_add_host(new, p); -cp - return 0; -} - -/* - The incoming request handlers -*/ - - -int termreq_h(conn_list_t *cl) -{ -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized TERMREQ from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got TERMREQ from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - cl->status.termreq = 1; - - terminate_connection(cl); -cp - return 0; -} - -int timeout_h(conn_list_t *cl) -{ -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized TIMEOUT from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got TIMEOUT from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - cl->status.termreq = 1; - terminate_connection(cl); -cp - return 0; -} - -int del_host_h(conn_list_t *cl) -{ - ip_t vpn_ip; - conn_list_t *fw; -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized DEL_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(sscanf(cl->buffer, "%*d %lx", &vpn_ip) != 1) - { - syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(!(fw = lookup_conn(vpn_ip))) - { - syslog(LOG_ERR, _("Got DEL_HOST for %d.%d.%d.%d from %s (%s) which does not exist?"), - IP_ADDR_V(vpn_ip), cl->vpn_hostname, cl->real_hostname); - return 0; - } - - /* Connections lists are really messed up if this happens */ - if(vpn_ip == myself->vpn_ip) - { - syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), - cl->vpn_hostname, cl->real_hostname); - sighup = 1; - return 0; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got DEL_HOST for %s (%s) from %s (%s)"), - fw->vpn_hostname, fw->real_hostname, cl->vpn_hostname, cl->real_hostname); - - notify_others(fw, cl, send_del_host); - - fw->status.termreq = 1; - fw->status.active = 0; - - terminate_connection(fw); -cp - return 0; -} - -int tcppacket_h(conn_list_t *cl) -{ - int len; -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized PACKET from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(sscanf(cl->buffer, "%*d %d", &len) != 1) - { - syslog(LOG_ERR, _("Got bad PACKET from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(len > MTU) - { - syslog(LOG_ERR, _("Got too big PACKET from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 3) - syslog(LOG_DEBUG, _("Got PACKET length %d from %s (%s)"), len, - cl->vpn_hostname, cl->real_hostname); - - cl->tcppacket=len; -cp - return 0; -} - - -int ping_h(conn_list_t *cl) -{ -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized PING from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got PING from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - cl->status.pinged = 0; - cl->status.got_pong = 1; - - send_pong(cl); -cp - return 0; -} - -int pong_h(conn_list_t *cl) -{ -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized PONG from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got PONG from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - cl->status.got_pong = 1; -cp - return 0; -} - -int add_host_h(conn_list_t *cl) -{ - ip_t real_ip; - ip_t vpn_ip; - ip_t vpn_mask; - unsigned short port; - int flags; - conn_list_t *ncn, *old; -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized ADD_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(sscanf(cl->buffer, "%*d %lx %lx/%lx:%hx %d", &real_ip, &vpn_ip, &vpn_mask, &port, &flags) != 5) - { - syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if((old = lookup_conn(vpn_ip))) - { - if((real_ip==old->real_ip) && (vpn_mask==old->vpn_mask) && (port==old->port)) - { - if(debug_lvl>1) - syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"), - old->vpn_hostname, old->real_hostname, cl->vpn_hostname, cl->real_hostname); - goto skip_add_host; /* One goto a day keeps the deeply nested if constructions away. */ - } - else - { - if(debug_lvl>1) - syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"), - old->vpn_hostname, old->real_hostname); - old->status.active = 0; - terminate_connection(old); - } - } - - /* Connections lists are really messed up if this happens */ - if(vpn_ip == myself->vpn_ip) - { - syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), - cl->vpn_hostname, cl->real_hostname); - sighup = 1; - return 0; - } - - ncn = new_conn_list(); - ncn->real_ip = real_ip; - ncn->real_hostname = hostlookup(htonl(real_ip)); - ncn->vpn_ip = vpn_ip; - ncn->vpn_mask = vpn_mask; - ncn->vpn_hostname = hostlookup(htonl(vpn_ip)); - ncn->port = port; - ncn->flags = flags; - ncn->nexthop = cl; - ncn->next = conn_list; - conn_list = ncn; - ncn->status.active = 1; - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got ADD_HOST for %s (%s) from %s (%s)"), - ncn->vpn_hostname, ncn->real_hostname, cl->vpn_hostname, cl->real_hostname); - - notify_others(ncn, cl, send_add_host); - -skip_add_host: -cp - return 0; -} - -int req_key_h(conn_list_t *cl) -{ - ip_t to; - ip_t from; - conn_list_t *fw; -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized REQ_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(sscanf(cl->buffer, "%*d %lx %lx", &to, &from) != 2) - { - syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got REQ_KEY origin %d.%d.%d.%d destination %d.%d.%d.%d from %s (%s)"), - IP_ADDR_V(from), IP_ADDR_V(to), cl->vpn_hostname, cl->real_hostname); - - if((to & myself->vpn_mask) == (myself->vpn_ip & myself->vpn_mask)) - { /* hey! they want something from ME! :) */ - send_key_answer(cl, from); - return 0; - } - - fw = lookup_conn(to); - - if(!fw) - { - syslog(LOG_ERR, _("Attempting to forward REQ_KEY to %d.%d.%d.%d, which does not exist?"), - IP_ADDR_V(to)); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Forwarding REQ_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); - - cl->buffer[cl->reqlen-1] = '\n'; - - if(write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} - -void set_keys(conn_list_t *cl, int expiry, char *key) -{ - char *ek; -cp - if(!cl->public_key) - { - cl->public_key = xmalloc(sizeof(*cl->key)); - cl->public_key->key = NULL; - } - - if(cl->public_key->key) - free(cl->public_key->key); - cl->public_key->length = strlen(key); - cl->public_key->expiry = expiry; - cl->public_key->key = xmalloc(cl->public_key->length + 1); - strcpy(cl->public_key->key, key); - - ek = make_shared_key(key); - - if(!cl->key) - { - cl->key = xmalloc(sizeof(*cl->key)); - cl->key->key = NULL; - } - - if(cl->key->key) - free(cl->key->key); - - cl->key->length = strlen(ek); - cl->key->expiry = expiry; - cl->key->key = xmalloc(cl->key->length + 1); - strcpy(cl->key->key, ek); -cp -} - -int ans_key_h(conn_list_t *cl) -{ - ip_t to; - ip_t from; - int expiry; - char *key; - conn_list_t *fw, *gk; -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized ANS_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(sscanf(cl->buffer, "%*d %lx %lx %d %as", &to, &from, &expiry, &key) != 4) - { - syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got ANS_KEY origin %d.%d.%d.%d destination %d.%d.%d.%d from %s (%s)"), - IP_ADDR_V(from), IP_ADDR_V(to), cl->vpn_hostname, cl->real_hostname); - - if(to == myself->vpn_ip) - { /* hey! that key's for ME! :) */ - gk = lookup_conn(from); - - if(!gk) - { - syslog(LOG_ERR, _("Receiving ANS_KEY origin %d.%d.%d.%d from %s (%s), which does not exist?"), - IP_ADDR_V(from), cl->vpn_hostname, cl->real_hostname); - return -1; - } - - set_keys(gk, expiry, key); - gk->status.validkey = 1; - gk->status.waitingforkey = 0; - flush_queues(gk); - return 0; - } - - fw = lookup_conn(to); - - if(!fw) - { - syslog(LOG_ERR, _("Attempting to forward ANS_KEY to %d.%d.%d.%d, which does not exist?"), - IP_ADDR_V(to)); - return -1; - } +static bool (*request_handlers[])(connection_t *) = { + id_h, metakey_h, challenge_h, chal_reply_h, ack_h, + status_h, error_h, termreq_h, + ping_h, pong_h, + add_subnet_h, del_subnet_h, + add_edge_h, del_edge_h, + key_changed_h, req_key_h, ans_key_h, tcppacket_h, +}; - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Forwarding ANS_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); +/* Request names */ - cl->buffer[cl->reqlen-1] = '\n'; +static char (*request_name[]) = { + "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY", "ACK", + "STATUS", "ERROR", "TERMREQ", + "PING", "PONG", + "ADD_SUBNET", "DEL_SUBNET", + "ADD_EDGE", "DEL_EDGE", "KEY_CHANGED", "REQ_KEY", "ANS_KEY", "PACKET", +}; - if((write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; +static avl_tree_t *past_request_tree; + +bool check_id(const char *id) { + for(; *id; id++) + if(!isalnum(*id) && *id != '_') + return false; + + return true; +} + +/* Generic request routines - takes care of logging and error + detection as well */ + +bool send_request(connection_t *c, const char *format, ...) { + va_list args; + char buffer[MAXBUFSIZE]; + int len, request = 0; + + /* Use vsnprintf instead of vxasprintf: faster, no memory + fragmentation, cleanup is automatic, and there is a limit on the + input buffer anyway */ + + va_start(args, format); + len = vsnprintf(buffer, MAXBUFSIZE, format, args); + va_end(args); + + if(len < 0 || len > MAXBUFSIZE - 1) { + logger(LOG_ERR, "Output buffer overflow while sending request to %s (%s)", + c->name, c->hostname); + return false; + } + + ifdebug(PROTOCOL) { + sscanf(buffer, "%d", &request); + ifdebug(META) + logger(LOG_DEBUG, "Sending %s to %s (%s): %s", + request_name[request], c->name, c->hostname, buffer); + else + logger(LOG_DEBUG, "Sending %s to %s (%s)", request_name[request], + c->name, c->hostname); + } + + buffer[len++] = '\n'; + + if(c == everyone) { + broadcast_meta(NULL, buffer, len); + return true; + } else + return send_meta(c, buffer, len); } -int key_changed_h(conn_list_t *cl) -{ - ip_t from; - conn_list_t *ik; -cp - if(!cl->status.active) - { - syslog(LOG_ERR, _("Got unauthorized KEY_CHANGED from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(sscanf(cl->buffer, "%*d %lx", &from) != 1) - { - syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } - - ik = lookup_conn(from); - - if(!ik) - { - syslog(LOG_ERR, _("Got KEY_CHANGED origin %d.%d.%d.%d from %s (%s), which does not exist?"), - IP_ADDR_V(from), cl->vpn_hostname, cl->real_hostname); - return -1; - } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got KEY_CHANGED origin %s from %s (%s)"), - ik->vpn_hostname, cl->vpn_hostname, cl->real_hostname); - - ik->status.validkey = 0; - ik->status.waitingforkey = 0; - - notify_others(ik, cl, send_key_changed); -cp - return 0; +void forward_request(connection_t *from) { + int request; + + ifdebug(PROTOCOL) { + sscanf(from->buffer, "%d", &request); + ifdebug(META) + logger(LOG_DEBUG, "Forwarding %s from %s (%s): %s", + request_name[request], from->name, from->hostname, + from->buffer); + else + logger(LOG_DEBUG, "Forwarding %s from %s (%s)", + request_name[request], from->name, from->hostname); + } + + from->buffer[from->reqlen - 1] = '\n'; + + broadcast_meta(from, from->buffer, from->reqlen); +} + +bool receive_request(connection_t *c) { + int request; + + if(proxytype == PROXY_HTTP && c->allow_request == ID) { + if(!c->buffer[0] || c->buffer[0] == '\r') + return true; + if(!strncasecmp(c->buffer, "HTTP/1.1 ", 9)) { + if(!strncmp(c->buffer + 9, "200", 3)) { + logger(LOG_DEBUG, "Proxy request granted"); + return true; + } else { + logger(LOG_DEBUG, "Proxy request rejected: %s", c->buffer + 9); + return false; + } + } + } + + if(sscanf(c->buffer, "%d", &request) == 1) { + if((request < 0) || (request >= LAST) || !request_handlers[request]) { + ifdebug(META) + logger(LOG_DEBUG, "Unknown request from %s (%s): %s", + c->name, c->hostname, c->buffer); + else + logger(LOG_ERR, "Unknown request from %s (%s)", + c->name, c->hostname); + + return false; + } else { + ifdebug(PROTOCOL) { + ifdebug(META) + logger(LOG_DEBUG, "Got %s from %s (%s): %s", + request_name[request], c->name, c->hostname, + c->buffer); + else + logger(LOG_DEBUG, "Got %s from %s (%s)", + request_name[request], c->name, c->hostname); + } + } + + if((c->allow_request != ALL) && (c->allow_request != request)) { + logger(LOG_ERR, "Unauthorized request from %s (%s)", c->name, + c->hostname); + return false; + } + + if(!request_handlers[request](c)) { + /* Something went wrong. Probably scriptkiddies. Terminate. */ + + logger(LOG_ERR, "Error while processing %s from %s (%s)", + request_name[request], c->name, c->hostname); + return false; + } + } else { + logger(LOG_ERR, "Bogus data received from %s (%s)", + c->name, c->hostname); + return false; + } + + return true; +} + +static int past_request_compare(const past_request_t *a, const past_request_t *b) { + return strcmp(a->request, b->request); +} + +static void free_past_request(past_request_t *r) { + if(r->request) + free(r->request); + + free(r); +} + +void init_requests(void) { + past_request_tree = avl_alloc_tree((avl_compare_t) past_request_compare, (avl_action_t) free_past_request); +} + +void exit_requests(void) { + avl_delete_tree(past_request_tree); +} + +bool seen_request(char *request) { + past_request_t *new, p = {NULL}; + + p.request = request; + + if(avl_search(past_request_tree, &p)) { + ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Already seen request"); + return true; + } else { + new = xmalloc(sizeof(*new)); + new->request = xstrdup(request); + new->firstseen = now; + avl_insert(past_request_tree, new); + return false; + } +} + +void age_past_requests(void) { + avl_node_t *node, *next; + past_request_t *p; + int left = 0, deleted = 0; + + for(node = past_request_tree->head; node; node = next) { + next = node->next; + p = node->data; + + if(p->firstseen + pinginterval <= now) + avl_delete_node(past_request_tree, node), deleted++; + else + left++; + } + + if(left || deleted) + ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Aging past requests: deleted %d, left %d", + deleted, left); } - -/* "Complete overhaul". */ - -int (*request_handlers[6])(conn_list_t*) = { - id_h, challenge_h, chal_reply_h, ack_h, - status_h, error_h, -}; - -char (*request_name[6]) = { - "ID", "CHALLENGE", "CHAL_REPLY", "ACK", - "STATUS", "ERROR", -};