X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=d52fd541f7ae441ddc3724bc3f7ac64bb99a6eb2;hp=51d95e9dd2e2c30a43ebed43a3b08563c6f3e80a;hb=361690b18c1f5464db7b9cef235c648784780dfb;hpb=028659bfbf164cb7a72831506896e291010b251f diff --git a/src/protocol.c b/src/protocol.c index 51d95e9d..d52fd541 100644 --- a/src/protocol.c +++ b/src/protocol.c @@ -1,6 +1,7 @@ /* protocol.c -- handle the meta-protocol - Copyright (C) 1999,2000 Ivo Timmermans + Copyright (C) 1999,2000 Ivo Timmermans , + 2000 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 @@ -15,6 +16,8 @@ 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 1.28.4.35 2000/09/22 16:20:07 guus Exp $ */ #include "config.h" @@ -31,766 +34,1009 @@ #include #include +#include + +#include + #include "conf.h" #include "encr.h" #include "net.h" #include "netutl.h" #include "protocol.h" -char buffer[MAXBUFSIZE+1]; -int buflen; - -/* Outgoing request routines */ +#include "system.h" -int send_ack(conn_list_t *cl) +int check_id(char *id) { -cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Send ACK to %s", cl->hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", ACK); + int i; - if((write(cl->meta_socket, buffer, buflen)) < 0) + for (i = 0; i < strlen(id); i++) { - syslog(LOG_ERR, "send failed: %d:%d: %m", __FILE__, __LINE__); - return -1; + if(!isalpha(id[i]) && id[i] != '_') + { + return 0; + } } - syslog(LOG_NOTICE, "Connection with %s activated.", cl->hostname); -cp - return 0; + return 1; } -int send_termreq(conn_list_t *cl) +/* 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[MAXBUFSIZE+1]; + int len; + cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Send TERMREQ to " IP_ADDR_S, - IP_ADDR_V(cl->vpn_ip)); + /* Use vsnprintf instead of vasprintf: faster, no memory fragmentation, cleanup is automatic, + and there is a limit on the input buffer anyway */ - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", TERMREQ, myself->vpn_ip); + va_start(args, request); + len = vsnprintf(buffer, MAXBUFSIZE+1, format, args); + va_end(args); - if(write(cl->meta_socket, buffer, buflen) < 0) + if(len < 0 || len > MAXBUFSIZE) { - if(debug_lvl > 1) - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Output buffer overflow while sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname); return -1; } + + if(debug_lvl >= DEBUG_PROTOCOL) + syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname); cp - return 0; + return send_meta(cl, buffer, length); } -int send_timeout(conn_list_t *cl) + +int send_meta(conn_list_t *cl, const char *buffer, int length) { cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Send TIMEOUT to " IP_ADDR_S, - IP_ADDR_V(cl->vpn_ip)); + if(debug_lvl >= DEBUG_META) + syslog(LOG_DEBUG, _("Sending %d bytes of metadata to %s (%s): %s"), int length, + cl->name, cl->hostname, buffer); - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", PINGTIMEOUT, myself->vpn_ip); + if(cl->status.encryptin) + { + /* FIXME: Do encryption */ + } - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(write(cl->meta_socket, buffer, length) < 0) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Sending meta data to %s (%s) failed: %m"), cl->name, cl->hostname); return -1; } cp return 0; } -int send_del_host(conn_list_t *cl, conn_list_t *new_host) +int broadcast_meta(conn_list_t *cl, const char *buffer, int length) { + conn_list_t *p; +cp + for(p = conn_list; p != NULL; p = p->next) + if(p != cl && p->status.meta && p->status.active) + send_meta(p, buffer, length); cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Sending delete host " IP_ADDR_S " to " IP_ADDR_S, - IP_ADDR_V(new_host->vpn_ip), IP_ADDR_V(cl->vpn_ip)); + return 0; +} - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", DEL_HOST, new_host->vpn_ip); +/* Connection protocol: + + Client Server + send_id(u) + send_challenge(R) + send_chal_reply(H) + send_id(u) + send_challenge(R) + send_chal_reply(H) + --------------------------------------- + Any negotations about the meta protocol + encryption go here(u). + --------------------------------------- + send_ack(u) + send_ack(u) + --------------------------------------- + Other requests(E)... + + (u) Unencrypted, + (R) RSA, + (H) SHA1, + (E) Encrypted with symmetric cipher. + + Part of the challenge is directly used to set the symmetric cipher key and the initial vector. + Since a man-in-the-middle cannot decrypt the RSA challenges, this means that he cannot get or + forge the key for the symmetric cipher. +*/ - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); - return -1; - } +int send_id(conn_list_t *cl) +{ cp - return 0; + return send_request(cl, "%d %s %d %lx", ID, myself->name, myself->protocol_version, myself->options); } -int send_ping(conn_list_t *cl) +int id_h(conn_list_t *cl) { + conn_list_t *old; cp - if(debug_lvl > 3) - syslog(LOG_DEBUG, "pinging " IP_ADDR_S, IP_ADDR_V(cl->vpn_ip)); + if(sscanf(cl->buffer, "%*d %as %d %lx", &cl->name, &cl->protocol_version, &cl->options) != 3) + { + syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname); + return -1; + } - buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", PING); + /* Check if version matches */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(cl->protocol_version != myself->protocol_version) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Peer %s (%s) uses incompatible version %d"), + cl->name, cl->hostname, cl->protocol_version); return -1; } -cp - return 0; -} -int send_pong(conn_list_t *cl) -{ -cp - buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", PONG); + /* Check if identity is a valid name */ + + if(!check_id(cl->name)) + { + syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname); + return -1; + } - if((write(cl->meta_socket, buffer, buflen)) < 0) + /* Load information about peer */ + + if(!read_id(cl)) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->name); 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->name))) + { + if(debug_lvl > DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->name, cl->hostname); + cl->status.outgoing = 0; + old->status.outgoing = 1; + terminate_connection(cl); + return 0; + } + } + + /* Send a challenge to verify the identity */ + + cl->allow_request = CHAL_REPLY; cp - return 0; + return send_challenge(cl); } -int send_add_host(conn_list_t *cl, conn_list_t *new_host) +int send_challenge(conn_list_t *cl) { + char buffer[CHAL_LENGTH*2+1]; cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Sending add host to " IP_ADDR_S, - IP_ADDR_V(cl->vpn_ip)); + /* Allocate buffers for the challenge */ - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx/%lx:%x\n", ADD_HOST, new_host->real_ip, new_host->vpn_ip, new_host->vpn_mask, new_host->port); + if(!cl->hischallenge) + cl->hischallenge = xmalloc(CHAL_LENGTH); - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); - return -1; - } + /* Copy random data to the buffer */ + + RAND_bytes(cl->hischallenge, CHAL_LENGTH); + + /* Convert the random data to a hexadecimal formatted string */ + + bin2hex(cl->hischallenge,buffer,CHAL_LENGTH); + buffer[keylength*2] = '\0'; + + /* Send the challenge */ + + cl->allow_request = CHAL_REPLY; cp - return 0; + return send_request(cl, "%d %s", CHALLENGE, buffer); } -int send_key_changed(conn_list_t *cl, conn_list_t *src) +int challenge_h(conn_list_t *cl) { + char *buffer; cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Sending KEY_CHANGED to " IP_ADDR_S, - IP_ADDR_V(cl->vpn_ip)); + if(sscanf(cl->buffer, "%*d %as", &buffer) != 1) + { + syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, cl->hostname); + return -1; + } - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", KEY_CHANGED, src->vpn_ip); + /* Check if the length of the challenge is all right */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(strlen(buffer) != CHAL_LENGTH*2) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname); + free(buffer); return -1; } + + /* Allocate buffers for the challenge */ + + if(!cl->mychallenge) + cl->mychallenge = xmalloc(CHAL_LENGTH); + + /* Convert the challenge from hexadecimal back to binary */ + + hex2bin(buffer,cl->mychallenge,CHAL_LENGTH); + free(buffer); + + /* Rest is done by send_chal_reply() */ cp - return 0; + return send_chal_reply(cl); } -void send_key_changed_all(void) +int send_chal_reply(conn_list_t *cl) { - conn_list_t *p; + char hash[SHA_DIGEST_LENGTH*2+1]; cp - for(p = conn_list; p != NULL; p = p->next) - if(p->status.meta && p->status.active) - send_key_changed(p, myself); + if(!cl->mychallenge) + { + syslog(LOG_ERR, _("Trying to send CHAL_REPLY to %s (%s) without a valid CHALLENGE"), cl->name, cl->hostname); + return -1; + } + + /* Calculate the hash from the challenge we received */ + + SHA1(cl->mychallenge, CHAL_LENGTH, hash); + + /* Convert the hash to a hexadecimal formatted string */ + + bin2hex(hash,hash,SHA_DIGEST_LENGTH); + hash[SHA_DIGEST_LENGTH*2] = '\0'; + + /* Send the reply */ + + if(cl->status.outgoing) + cl->allow_request = ID; + else + cl->allow_request = ACK; + cp + return send_request(cl, "%d %s", CHAL_REPLY, hash); } -int send_basic_info(conn_list_t *cl) +int chal_reply_h(conn_list_t *cl) { + char *hishash; + char myhash[SHA_DIGEST_LENGTH]; cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Send BASIC_INFO to " IP_ADDR_S, - IP_ADDR_V(cl->real_ip)); + if(sscanf(cl->buffer, "%*d %as", &hishash) != 2) + { + syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname); + free(hishash); + return -1; + } - buflen = snprintf(buffer, MAXBUFSIZE, "%d %d %lx/%lx:%x\n", BASIC_INFO, PROT_CURRENT, myself->vpn_ip, myself->vpn_mask, myself->port); + /* Check if the length of the hash is all right */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(strlen(hishash) != SHA_DIGEST_LENGTH*2) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->name, cl->hostname); + free(hishash); return -1; } -cp - return 0; -} -int send_passphrase(conn_list_t *cl) -{ - passphrase_t tmp; -cp - encrypt_passphrase(&tmp); + /* Convert the hash to binary format */ + + hex2bin(hishash, hishash, SHA_DIGEST_LENGTH); - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Send PASSPHRASE %s to " IP_ADDR_S, - tmp.phrase, IP_ADDR_V(cl->vpn_ip)); + /* Calculate the hash from the challenge we sent */ - buflen = snprintf(buffer, MAXBUFSIZE, "%d %s\n", PASSPHRASE, tmp.phrase); + SHA1(cl->hischallenge, CHAL_LENGTH, myhash); - if((write(cl->meta_socket, buffer, buflen)) < 0) + /* Verify the incoming hash with the calculated hash */ + + if(!memcmp(hishash, myhash, SHA_DIGEST_LENGTH)) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Intruder: wrong challenge reply from %s (%s)"), cl->name, cl->hostname); + free(hishash); return -1; } + + free(hishash); + + /* Identity has now been positively verified. + If we are accepting this new connection, then send our identity, + if we are making this connecting, acknowledge. + */ cp - return 0; + if(cl->status.outgoing) + { + cl->allow_request = ACK; + return send_ack(cl); + } + else + { + cl->allow_request = CHALLENGE; + return send_id(cl); + } } -int send_public_key(conn_list_t *cl) +int send_ack(conn_list_t *cl) { cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Send PUBLIC_KEY %s to " IP_ADDR_S, - my_public_key_base36, IP_ADDR_V(cl->vpn_ip)); + return send_request(cl, "%d", ACK); +} - buflen = snprintf(buffer, MAXBUFSIZE, "%d %s\n", PUBLIC_KEY, my_public_key_base36); +int ack_h(conn_list_t *cl) +{ + conn_list_t *old; +cp + /* Okay, before we active the connection, we check if there is another entry + in the connection list with the same name. If so, it presumably is an + old connection that has timed out but we don't know it yet. + */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + while((old = lookup_id(cl->name))) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); - return -1; + if(debug_lvl > DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Removing old entry for %s at %s in favour of new connection from %s"), + cl->name, old->hostname, cl->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->name, cl->hostname); + + /* Exchange information about other tinc daemons */ + + notify_others(cl, NULL, send_add_host); + notify_one(cl); + + upstreamindex = 0; + cp - return 0; + if(cl->status.outgoing) + return 0; + else + return send_ack(cl); } -int send_calculate(conn_list_t *cl, char *k) +/* Address and subnet information exchange */ + +int send_add_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet) { + int x; + char *netstr; cp - buflen = snprintf(buffer, MAXBUFSIZE, "%d %s\n", CALCULATE, k); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); - return -1; - } + x = send_request(cl, "%d %s %s", ADD_SUBNET, + other->name, netstr = net2str(subnet)); + free(netstr); cp - return 0; + return x; } -int send_key_request(ip_t to) +int add_subnet_h(conn_list_t *cl) { - conn_list_t *fw; + char *subnetstr; + char *name; + conn_list_t *owner; + subnet_t *subnet, *old; cp - fw = lookup_conn(to); - if(!fw) + if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3) { - syslog(LOG_ERR, "Attempting to send key request to " IP_ADDR_S ", which does not exist?", - IP_ADDR_V(to)); + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s)"), cl->name, cl->hostname); + free(name); free(subnetstr); return -1; } - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Sending out request for public key to " IP_ADDR_S, - IP_ADDR_V(fw->nexthop->vpn_ip)); + /* Check if owner name is a valid */ - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx\n", REQ_KEY, to, myself->vpn_ip); - - if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0) + if(!check_id(name)) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname); + free(name); free(subnetstr); 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 + /* Check if subnet string is valid */ - fw = lookup_conn(to); - - if(!fw) + if((subnet = str2net(subnetstr)) == -1) { - syslog(LOG_ERR, "Attempting to send key answer to " IP_ADDR_S ", which does not exist?", - IP_ADDR_V(to)); + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname); + free(name); free(subnetstr); return -1; } - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Sending public key to " IP_ADDR_S, - IP_ADDR_V(fw->nexthop->vpn_ip)); + free(subnetstr); + + /* Check if somebody tries to add a subnet of ourself */ + + if(!strcmp(name, myself->name)) + { + syslog(LOG_ERR, _("Warning: got ADD_SUBNET from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); + free(name); + sighup = 1; + return 0; + } - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx %d %s\n", ANS_KEY, to, myself->vpn_ip, my_key_expiry, my_public_key_base36); + /* Check if the owner of the new subnet is in the connection list */ - if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0) + if(!(owner = lookup_id(name)) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Got ADD_SUBNET for %s from %s (%s) which is not in our connection list"), + name, cl->name, cl->hostname); + free(name); return -1; } + + /* If everything is correct, add the subnet to the list of the owner */ cp - return 0; + return subnet_add(owner, subnet); } -/* - 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*)) +int send_del_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet) { - 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; + return send_request(cl, "%d %s %s", DEL_SUBNET, other->name, net2str(subnet)); } -/* - notify one connection of everything - i have connected -*/ -int notify_one(conn_list_t *new) +int del_subnet_h(conn_list_t *cl) { - conn_list_t *p; + char *subnetstr; + char *name; + conn_list_t *owner; + subnet_t *subnet, *old; cp - for(p = conn_list; p != NULL; p = p->next) - if(p != new && p->status.active) - send_add_host(new, p); + if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s)"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + /* Check if owner name is a valid */ + + if(!check_id(name)) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + /* Check if subnet string is valid */ + + if((subnet = str2net(subnetstr)) == -1) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname); + free(name); free(subnetstr); + return -1; + } + + free(subnetstr); + + /* Check if somebody tries to add a subnet of ourself */ + + if(!strcmp(name, myself->name)) + { + syslog(LOG_ERR, _("Warning: got DEL_SUBNET from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); + free(name); + sighup = 1; + return 0; + } + + /* Check if the owner of the new subnet is in the connection list */ + + if(!(owner = lookup_id(name)) + { + syslog(LOG_ERR, _("Got DEL_SUBNET for %s from %s (%s) which is not in our connection list"), + name, cl->name, cl->hostname); + free(name); + return -1; + } + + /* If everything is correct, add the subnet to the list of the owner */ cp - return 0; + return subnet_del(owner, subnet); } -/* - The incoming request handlers -*/ +/* New and closed connections notification */ + +int send_add_host(conn_list_t *cl, conn_list_t *other) +{ +cp + return send_request(cl, "%d %s %s %lx:%d %lx", ADD_HOST, + myself->name, other->name, other->real_ip, other->port, other->options); +} -int basic_info_h(conn_list_t *cl) +int add_host_h(conn_list_t *cl) { + char *sender; + conn_list_t *old, *new, *hisuplink; cp - if(sscanf(cl->buffer, "%*d %d %lx/%lx:%hx", &cl->protocol_version, &cl->vpn_ip, &cl->vpn_mask, &cl->port) != 4) + new = new_conn_list(); + + if(sscanf(cl->buffer, "%*d %as %as %lx:%d %lx", &sender, &new->name, &new->address, &new->port, &new->options) != 5) { - syslog(LOG_ERR, "got bad BASIC_INFO request: %s", cl->buffer); + syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->name, cl->hostname); return -1; - } + } + + /* Check if identity is a valid name */ - if(cl->protocol_version != PROT_CURRENT) + if(!check_id(new->name) || !check_id(sender)) { - syslog(LOG_ERR, "Peer uses incompatible protocol version %d.", - cl->protocol_version); + syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); + free(sender); return -1; } - if(debug_lvl > 2) - syslog(LOG_DEBUG, "got BASIC_INFO(%hd," IP_ADDR_S "," IP_ADDR_S ")", cl->port, - IP_ADDR_V(cl->vpn_ip), IP_ADDR_V(cl->vpn_mask)); - if(debug_lvl > 1) - syslog(LOG_DEBUG, "Peer uses protocol version %d", - cl->protocol_version); + /* Check if somebody tries to add ourself */ - if(cl->status.outgoing) + if(!strcmp(new->name, myself->name)) { - if(setup_vpn_connection(cl) < 0) - return -1; - send_basic_info(cl); + syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname); + sighup = 1; + free(sender); + return 0; } - else + + /* We got an ADD_HOST from ourself!? */ + + if(!strcmp(sender, myself->name)) { - if(setup_vpn_connection(cl) < 0) - return -1; - send_passphrase(cl); + syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) from ourself, restarting"), cl->name, cl->hostname); + sighup = 1; + free(sender); + return 0; } -cp - return 0; -} -int passphrase_h(conn_list_t *cl) -{ -cp - cl->pp = xmalloc(sizeof(*(cl->pp))); + /* Lookup his uplink */ - if(sscanf(cl->buffer, "%*d %as", &(cl->pp->phrase)) != 1) + if(!(new->hisuplink = lookup_id(sender)) { - syslog(LOG_ERR, "got bad PASSPHRASE request: %s", cl->buffer); + syslog(LOG_ERR, _("Got ADD_HOST from %s (%s) with origin %s which is not in our connection list"), + sender, cl->name, cl->hostname); + free(sender); return -1; } - cl->pp->len = strlen(cl->pp->phrase); - if(debug_lvl > 2) - syslog(LOG_DEBUG, "got PASSPHRASE"); + free(sender); + + /* Fill in more of the new conn_list structure */ + + new->hostname = hostlookup(htonl(new->real_ip)); + + /* Check if the new host already exists in the connnection list */ + + if((old = lookup_id(new->name))) + { + if((new->real_ip == old->real_ip) && (new->port == old->port)) + { + if(debug_lvl > DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"), + old->name, old->hostname, new->name, new->hostname); + return 0; + } + else + { + if(debug_lvl > DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"), + old->name, old->hostname); + old->status.active = 0; + terminate_connection(old); + } + } + + /* Fill in rest of conn_list structure */ + + new->myuplink = cl; + new->status.active = 1; + + /* Hook it up into the conn_list */ + + conn_list_add(conn_list, new); + + /* Tell the rest about the new host */ + + notify_others(new, cl, send_add_host); - if(cl->status.outgoing) - send_passphrase(cl); - else - send_public_key(cl); cp return 0; } -int public_key_h(conn_list_t *cl) +int send_del_host(conn_list_t *cl, conn_list_t *other) { - char *g_n; - conn_list_t *old; cp - if(sscanf(cl->buffer, "%*d %as", &g_n) != 1) + return send_request(cl, "%d %s %s %lx:%d %lx", DEL_HOST, + myself->name, other->name, other->real_ip, other->port, other->options); +} + +int del_host_h(conn_list_t *cl) +{ + char *name; + char *sender; + ip_t address; + port_t port; + int options; + conn_list_t *old, *hisuplink; + +cp + if(sscanf(cl->buffer, "%*d %as %as %lx:%d %lx", &sender, &name, &address, &port, &options) != 5) { - syslog(LOG_ERR, "got bad PUBLIC_KEY request: %s", cl->buffer); - return -1; - } + syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), + cl->name, cl->hostname); + return -1; + } - if(debug_lvl > 2) - syslog(LOG_DEBUG, "got PUBLIC_KEY %s", g_n); + /* Check if identity is a valid name */ - if(verify_passphrase(cl, g_n)) + if(!check_id(name) || !check_id(sender)) { - /* intruder! */ - syslog(LOG_ERR, "Intruder: passphrase does not match."); + syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); + free(name); free(sender); return -1; } - if(debug_lvl > 2) - syslog(LOG_INFO, "Passphrase OK"); + /* Check if somebody tries to delete ourself */ - if(cl->status.outgoing) - send_public_key(cl); - else - send_ack(cl); + if(!strcmp(name, myself->name)) + { + syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); + free(name); free(sender); + sighup = 1; + return 0; + } - /* 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. Because our - conn_list entry is not active, lookup_conn will skip ourself. */ + /* We got an ADD_HOST from ourself!? */ - while(old=lookup_conn(cl->vpn_ip)) - terminate_connection(old); + if(!strcmp(sender, myself->name)) + { + syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) from ourself, restarting"), cl->name, cl->hostname); + sighup = 1; + free(name); free(sender); + return 0; + } - cl->status.active = 1; - notify_others(cl, NULL, send_add_host); - notify_one(cl); + /* Lookup his uplink */ + + if(!(hisuplink = lookup_id(sender)) + { + syslog(LOG_ERR, _("Got DEL_HOST from %s (%s) with origin %s which is not in our connection list"), + cl->name, cl->hostname, sender); + free(name); free(sender); + return -1; + } + + free(sender); + + /* Check if the new host already exists in the connnection list */ + + if(!(old = lookup_id(name))) + { + syslog(LOG_ERR, _("Got DEL_HOST from %s (%s) for %s which is not in our connection list"), + name, cl->name, cl->hostname); + free(name); + return -1; + } + + /* Check if the rest matches */ + + if(address!=old->address || port!=old->port || options!=old->options || hisuplink!=old->hisuplink || cl!=old->myuplink) + { + syslog(LOG_WARNING, _("Got DEL_HOST from %s (%s) for %s which doesn't match"), cl->name, cl->hostname, old->name); + return 0; + } + + /* Ok, since EVERYTHING seems to check out all right, delete it */ + + old->status.termreq = 1; + old->status.active = 0; + + terminate_connection(old); cp return 0; } -int ack_h(conn_list_t *cl) +/* Status and error notification routines */ + +int send_status(conn_list_t *cl, int statusno, char *statusstring) { cp - if(debug_lvl > 2) - syslog(LOG_DEBUG, "got ACK"); - - cl->status.active = 1; - syslog(LOG_NOTICE, "Connection with %s activated.", cl->hostname); + if(!statusstring) + statusstring = status_text[statusno]; cp - return 0; + return send_request(cl, "%d %d %s", STATUS, statusno, statusstring); } -int termreq_h(conn_list_t *cl) +int status_h(conn_list_t *cl) { + int statusno; + char *statusstring; cp - syslog(LOG_NOTICE, IP_ADDR_S " wants to quit", IP_ADDR_V(cl->vpn_ip)); - cl->status.termreq = 1; - terminate_connection(cl); + if(sscanf(cl->buffer, "%*d %d %as", &statusno, &statusstring) != 2) + { + syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), + cl->name, cl->hostname); + return -1; + } + + if(debug_lvl > DEBUG_STATUS) + { + syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"), + cl->name, cl->hostname, status_text[statusno], statusstring); + } - notify_others(cl, NULL, send_del_host); cp + free(statusstring); return 0; } -int timeout_h(conn_list_t *cl) +int send_error(conn_list_t *cl, int errno, char *errstring) { cp - syslog(LOG_NOTICE, IP_ADDR_S " says it's gotten a timeout from us", IP_ADDR_V(cl->vpn_ip)); - cl->status.termreq = 1; - terminate_connection(cl); -cp - return 0; + if(!errstring) + errstring = strerror(errno); + return send_request(cl, "%d %d %s", ERROR, errno, errstring); } -int del_host_h(conn_list_t *cl) +int error_h(conn_list_t *cl) { - ip_t vpn_ip; - conn_list_t *fw; + int errno; + char *errorstring; cp - if(sscanf(cl->buffer, "%*d %lx", &vpn_ip) != 1) + if(sscanf(cl->buffer, "%*d %d %as", &errno, &errorstring) != 2) { - syslog(LOG_ERR, "got bad DEL_HOST request: %s", cl->buffer); + syslog(LOG_ERR, _("Got bad error from %s (%s)"), + cl->name, cl->hostname); return -1; - } - - if(debug_lvl > 2) - syslog(LOG_DEBUG, "got DEL_HOST for " IP_ADDR_S, - IP_ADDR_V(vpn_ip)); + } - if(!(fw = lookup_conn(vpn_ip))) + if(debug_lvl > DEBUG_error) { - syslog(LOG_ERR, "Somebody wanted to delete " IP_ADDR_S " which does not exist?", - IP_ADDR_V(vpn_ip)); - return 0; + syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"), + cl->name, cl->hostname, strerror(errno), errorstring); } - notify_others(cl, fw, send_del_host); + free(errorstring); + cl->status.termreq = 1; + terminate_connection(cl); +cp + return 0; +} + +int send_termreq(conn_list_t *cl) +{ +cp + return send_request(cl, "%d", TERMREQ); +} - fw->status.termreq = 1; - terminate_connection(fw); +int termreq_h(conn_list_t *cl) +{ +cp + cl->status.termreq = 1; + terminate_connection(cl); cp return 0; } +/* Keepalive routines - FIXME: needs a closer look */ + +int send_ping(conn_list_t *cl) +{ + cl->status.pinged = 1; +cp + return send_request(cl, "%d", PING); +} + int ping_h(conn_list_t *cl) { cp - if(debug_lvl > 3) - syslog(LOG_DEBUG, "responding to ping from " IP_ADDR_S, IP_ADDR_V(cl->vpn_ip)); - cl->status.pinged = 0; - cl->status.got_pong = 1; + return send_pong(cl); +} - send_pong(cl); +int send_pong(conn_list_t *cl) +{ cp - return 0; + return send_request(cl, "%d", PONG); } int pong_h(conn_list_t *cl) { cp - if(debug_lvl > 3) - syslog(LOG_DEBUG, "ok, got pong from " IP_ADDR_S, IP_ADDR_V(cl->vpn_ip)); cl->status.got_pong = 1; cp return 0; } -int add_host_h(conn_list_t *cl) +/* Key exchange */ + +int send_key_changed(conn_list_t *from, conn_list_t *cl) { - ip_t real_ip; - ip_t vpn_ip; - ip_t vpn_mask; - unsigned short port; - conn_list_t *ncn, *fw; + conn_list_t *p; cp - if(sscanf(cl->buffer, "%*d %lx %lx/%lx:%hx", &real_ip, &vpn_ip, &vpn_mask, &port) != 4) - { - syslog(LOG_ERR, "got bad ADD_HOST request: %s", cl->buffer); - return -1; - } - - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Add host request from " IP_ADDR_S, IP_ADDR_V(cl->vpn_ip)); - if(debug_lvl > 3) - syslog(LOG_DEBUG, "got ADD_HOST(" IP_ADDR_S "," IP_ADDR_S ",%hd)", - IP_ADDR_V(vpn_ip), IP_ADDR_V(vpn_mask), port); - - /* - Suggestion of Hans Bayle - */ - if((fw = lookup_conn(vpn_ip))) + for(p = conn_list; p != NULL; p = p->next) { - notify_others(fw, cl, send_add_host); - return 0; + if(p!=cl && p->status.meta && p->status.active) + send_request(p, "%d %s", KEY_CHANGED, + from->name); } - - ncn = new_conn_list(); - ncn->real_ip = real_ip; - ncn->vpn_ip = vpn_ip; - ncn->vpn_mask = vpn_mask; - ncn->port = port; - ncn->hostname = hostlookup(real_ip); - ncn->nexthop = cl; - ncn->next = conn_list; - conn_list = ncn; - ncn->status.active = 1; - notify_others(ncn, cl, send_add_host); cp return 0; } -int req_key_h(conn_list_t *cl) +int key_changed_h(conn_list_t *cl) { - ip_t to; - ip_t from; - conn_list_t *fw; + char *from_id; + conn_list_t *from; cp - if(sscanf(cl->buffer, "%*d %lx %lx", &to, &from) != 2) - { - syslog(LOG_ERR, "got bad request: %s", cl->buffer); - return -1; - } - - if(debug_lvl > 2) - syslog(LOG_DEBUG, "got REQ_KEY from " IP_ADDR_S " for " IP_ADDR_S, - IP_ADDR_V(from), IP_ADDR_V(to)); - - 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) + if(sscanf(cl->buffer, "%*d %as", &from_id) != 1) { - syslog(LOG_ERR, "Attempting to forward key request to " IP_ADDR_S ", which does not exist?", - IP_ADDR_V(to)); + syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), + cl->name, cl->hostname); return -1; } - if(debug_lvl > 3) - syslog(LOG_DEBUG, "Forwarding request for public key to " IP_ADDR_S, - IP_ADDR_V(fw->nexthop->vpn_ip)); - - cl->buffer[cl->reqlen-1] = '\n'; - - if(write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen) < 0) + if(!(from = lookup_id(from_id))) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); + syslog(LOG_ERR, _("Got KEY_CHANGED from %s (%s) origin %s which does not exist in our connection list"), + cl->name, cl->hostname, from_id); + free(from_id); return -1; } + + free(from_id); + + from->status.validkey = 0; + from->status.waitingforkey = 0; + + send_key_changed(from, cl); cp return 0; } -void set_keys(conn_list_t *cl, int expiry, char *key) +int send_req_key(conn_list_t *from, conn_list_t *to) { - 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 + return send_request(to->nexthop, "%d %s %s", REQ_KEY, + from->name, to->name); } -int ans_key_h(conn_list_t *cl) +int req_key_h(conn_list_t *cl) { - ip_t to; - ip_t from; - int expiry; - char *key; - conn_list_t *fw, *gk; + char *from_id, *to_id; + conn_list_t *from, *to; cp - if(sscanf(cl->buffer, "%*d %lx %lx %d %as", &to, &from, &expiry, &key) != 4) + if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2) { - syslog(LOG_ERR, "got bad ANS_KEY request: %s", cl->buffer); + syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), + cl->name, cl->hostname); return -1; - } - - if(debug_lvl > 3) - syslog(LOG_DEBUG, "got ANS_KEY from " IP_ADDR_S " for " IP_ADDR_S, - IP_ADDR_V(from), IP_ADDR_V(to)); - - if(to == myself->vpn_ip) - { /* hey! that key's for ME! :) */ - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Yeah! key arrived. Now do something with it."); - gk = lookup_conn(from); - - if(!gk) - { - syslog(LOG_ERR, "Receiving key from " IP_ADDR_S ", which does not exist?", - IP_ADDR_V(from)); - 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) + if(!(from = lookup_id(from_id))) { - syslog(LOG_ERR, "Attempting to forward key to " IP_ADDR_S ", which does not exist?", - IP_ADDR_V(to)); + syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) origin %s which does not exist in our connection list"), + cl->name, cl->hostname, from_id); + free(from_id); free(to_id); return -1; } - if(debug_lvl > 2) - syslog(LOG_DEBUG, "Forwarding public key to " IP_ADDR_S, - IP_ADDR_V(fw->nexthop->vpn_ip)); - - cl->buffer[cl->reqlen-1] = '\n'; + /* Check if this key request is for us */ - if((write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen)) < 0) + if(!strcmp(to_id, myself->name)) { - syslog(LOG_ERR, "send failed: %s:%d: %m", __FILE__, __LINE__); - return -1; + send_ans_key(myself, from, myself->datakey->key); + } + else + { + if(!(to = lookup_id(to_id))) + { + syslog(LOG_ERR, _("Got REQ_KEY from %s (%s) destination %s which does not exist in our connection list"), + cl->name, cl->hostname, to_id); + free(from_id); free(to_id); + return -1; + } + send_req_key(from, to); } + + free(from_id); free(to_id); cp return 0; } -int key_changed_h(conn_list_t *cl) +int send_ans_key(conn_list_t *from, conn_list_t *to, char *datakey) { - ip_t from; - conn_list_t *ik; cp - if(sscanf(cl->buffer, "%*d %lx", &from) != 1) + return send_request(to->nexthop, "%d %s %s %s", ANS_KEY, + from->name, to->name, datakey); +} + +int ans_key_h(conn_list_t *cl) +{ + char *from_id, *to_id, *datakey; + int keylength; + conn_list_t *from, *to; +cp + if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &datakey) != 3) { - syslog(LOG_ERR, "got bad ANS_KEY request: %s", cl->buffer); + syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), + cl->name, cl->hostname); return -1; - } - - if(debug_lvl > 2) - syslog(LOG_DEBUG, "got KEY_CHANGED from " IP_ADDR_S, - IP_ADDR_V(from)); - - ik = lookup_conn(from); + } - if(!ik) + if(!(from = lookup_id(from_id))) { - syslog(LOG_ERR, "Got changed key from " IP_ADDR_S ", which does not exist?", - IP_ADDR_V(from)); + syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) origin %s which does not exist in our connection list"), + cl->name, cl->hostname, from_id); + free(from_id); free(to_id); free(datakey); return -1; } - ik->status.validkey = 0; - ik->status.waitingforkey = 0; + /* Check if this key request is for us */ + + if(!strcmp(to_id, myself->name)) + { + /* It is for us, convert it to binary and set the key with it. */ + + keylength = strlen(datakey); - if(debug_lvl > 3) - syslog(LOG_DEBUG, "Forwarding key invalidation request"); + if((keylength%2) || (keylength <= 0)) + { + syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key"), + cl->name, cl->hostname, from->name); + free(from_id); free(to_id); free(datakey); + return -1; + } + keylength /= 2; + hex2bin(datakey, datakey, keylength); + BF_set_key(cl->datakey, keylength, datakey); + } + else + { + if(!(to = lookup_id(to_id))) + { + syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) destination %s which does not exist in our connection list"), + cl->name, cl->hostname, to_id); + free(from_id); free(to_id); free(datakey); + return -1; + } + send_ans_key(from, to, datakey); + } - notify_others(cl, ik, send_key_changed); + free(from_id); free(to_id); free(datakey); cp return 0; } -int (*request_handlers[256])(conn_list_t*) = { - 0, ack_h, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - termreq_h, timeout_h, del_host_h, 0, 0, 0, 0, 0, 0, 0, - ping_h, pong_h, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - add_host_h, basic_info_h, passphrase_h, public_key_h, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - req_key_h, ans_key_h, key_changed_h, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 +/* Jumptable for the request handlers */ + +int (*request_handlers[])(conn_list_t*) = { + id_h, challenge_h, chal_reply_h, ack_h, + status_h, error_h, termreq_h, + ping_h, pong_h, + add_host_h, del_host_h, + add_subnet_h, del_subnet_h, + key_changed_h, req_key_h, ans_key_h, +}; + +/* Request names */ + +char (*request_name[]) = { + "ID", "CHALLENGE", "CHAL_REPLY", "ACK", + "STATUS", "ERROR", "TERMREQ", + "PING", "PONG", + "ADD_HOST", "DEL_HOST", + "ADD_SUBNET", "DEL_SUBNET", + "KEY_CHANGED", "REQ_KEY", "ANS_KEY", };