X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=aab226600a8b01ce48830f22bdc18ca538c0aea7;hp=69a6918f735028dd841e5e7c3f0958ac1edc99e9;hb=6bd93e4c064578b545cb6dcaa28fffb229c929ff;hpb=f8b4a000d008082e5c7e511a49318b8dea8fd08d diff --git a/src/protocol.c b/src/protocol.c index 69a6918f..aab22660 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 + Copyright (C) 1999-2001 Ivo Timmermans , + 2000,2001 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 @@ -17,7 +17,7 @@ along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - $Id: protocol.c,v 1.28.4.63 2000/11/22 18:54:08 guus Exp $ + $Id: protocol.c,v 1.28.4.97 2001/07/01 21:42:13 guus Exp $ */ #include "config.h" @@ -31,9 +31,12 @@ #include #include #include +#include #include #include +#include +#include #include @@ -65,6 +68,8 @@ #include "system.h" +int mykeyused = 0; + int check_id(char *id) { int i; @@ -72,11 +77,12 @@ int check_id(char *id) for (i = 0; i < strlen(id); i++) if(!isalnum(id[i]) && id[i] != '_') return -1; - + return 0; } -/* Generic request routines - takes care of logging and error detection as well */ +/* Generic request routines - takes care of logging and error + detection as well */ int send_request(connection_t *cl, const char *format, ...) { @@ -85,8 +91,9 @@ int send_request(connection_t *cl, const char *format, ...) int len, request; cp - /* Use vsnprintf instead of vasprintf: faster, no memory fragmentation, cleanup is automatic, - and there is a limit on the input buffer anyway */ + /* Use vsnprintf instead of vasprintf: 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); @@ -99,11 +106,15 @@ cp return -1; } - len++; - if(debug_lvl >= DEBUG_PROTOCOL) - syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname); + { + if(debug_lvl >= DEBUG_META) + syslog(LOG_DEBUG, _("Sending %s to %s (%s): %s"), request_name[request], cl->name, cl->hostname, buffer); + else + syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], cl->name, cl->hostname); + } + buffer[len++] = '\n'; cp return send_meta(cl, buffer, len); } @@ -111,20 +122,31 @@ cp int receive_request(connection_t *cl) { int request; -cp +cp if(sscanf(cl->buffer, "%d", &request) == 1) { - if((request < 0) || (request > 255) || (request_handlers[request] == NULL)) + if((request < 0) || (request >= LAST) || (request_handlers[request] == NULL)) { - syslog(LOG_ERR, _("Unknown request from %s (%s)"), - cl->name, cl->hostname); + if(debug_lvl >= DEBUG_META) + syslog(LOG_DEBUG, _("Unknown request from %s (%s): %s"), + cl->name, cl->hostname, cl->buffer); + else + syslog(LOG_ERR, _("Unknown request from %s (%s)"), + cl->name, cl->hostname); + return -1; } else { if(debug_lvl >= DEBUG_PROTOCOL) - syslog(LOG_DEBUG, _("Got %s from %s (%s)"), - request_name[request], cl->name, cl->hostname); + { + if(debug_lvl >= DEBUG_META) + syslog(LOG_DEBUG, _("Got %s from %s (%s): %s"), + request_name[request], cl->name, cl->hostname, cl->buffer); + else + syslog(LOG_DEBUG, _("Got %s from %s (%s)"), + request_name[request], cl->name, cl->hostname); + } } if((cl->allow_request != ALL) && (cl->allow_request != request)) @@ -151,38 +173,11 @@ cp return 0; } -/* Connection protocol: - - Client Server - send_id(u) - send_challenge(R) - send_chal_reply(H) - send_id(u) - send_challenge(R) - send_chal_reply(H) - --------------------------------------- - send_metakey(R) - send_metakey(R) - --------------------------------------- - 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. -*/ +/* The authentication protocol is described in detail in doc/SECURITY2, + the rest will be described in doc/PROTOCOL. */ int send_id(connection_t *cl) { -cp - cl->allow_request = CHALLENGE; cp return send_request(cl, "%d %s %d %lx %hd", ID, myself->name, myself->protocol_version, myself->options, myself->port); } @@ -190,9 +185,11 @@ cp int id_h(connection_t *cl) { connection_t *old; - config_t const *cfg; + unsigned short int port; + char name[MAX_STRING_SIZE]; + avl_node_t *node; cp - if(sscanf(cl->buffer, "%*d %as %d %lx %hd", &cl->name, &cl->protocol_version, &cl->options, &cl->port) != 4) + if(sscanf(cl->buffer, "%*d "MAX_STRING" %d %lx %hd", name, &cl->protocol_version, &cl->options, &port) != 4) { syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname); return -1; @@ -209,11 +206,18 @@ cp /* Check if identity is a valid name */ - if(check_id(cl->name)) + if(check_id(name)) { syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname); return -1; } + + /* Copy string to cl */ + + if(cl->name) + free(cl->name); + + cl->name = xstrdup(name); /* Load information about peer */ @@ -223,43 +227,133 @@ cp return -1; } - /* First check if the host we connected to is already in our + /* First check if the host 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((old = lookup_id(cl->name))) + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("%s (%s) is already in our connection list"), cl->name, cl->hostname); + if(cl->status.outgoing) { - 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; } + terminate_connection(cl); + return 0; } /* Now we can add the name to the id tree */ id_add(cl); - /* Read in the public key, so that we can send a challenge */ + /* And uhr... cl->port just changed so we have to unlink it from the connection tree and re-insert... */ + + node = avl_unlink(connection_tree, cl); + cl->port = port; + if(!avl_insert_node(connection_tree, node)) + { + old = avl_search_node(connection_tree, node)->data; + syslog(LOG_ERR, _("%s is listening on %s:%hd, which is already in use by %s!"), + cl->name, cl->hostname, cl->port, old->name); + return -1; + } + + /* Read in the public key, so that we can send a metakey */ + + if(read_rsa_public_key(cl)) + return -1; + + cl->allow_request = METAKEY; +cp + return send_metakey(cl); +} + +int ack_h(connection_t *cl) +{ + config_t const *cfg; + connection_t *old, *p; + subnet_t *subnet; + avl_node_t *node, *node2; +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((cfg = get_config_val(cl->config, config_publickey))) + while((old = lookup_id(cl->name))) { - cl->rsa_key = RSA_new(); - BN_hex2bn(&cl->rsa_key->n, cfg->data.ptr); - BN_hex2bn(&cl->rsa_key->e, "FFFF"); + 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); + + terminate_connection(old); } - else + + /* Activate this connection */ + + cl->allow_request = ALL; + cl->status.active = 1; + cl->nexthop = cl; + cl->cipher_pkttype = EVP_bf_cbc(); + cl->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len; + + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname); + + if(cl->status.outgoing) + seconds_till_retry = 5; /* Reset retry timeout */ +cp + /* Check some options */ + + if((cfg = get_config_val(cl->config, config_indirectdata))) { - syslog(LOG_ERR, _("No public key known for %s (%s)"), cl->name, cl->hostname); - return -1; + if(cfg->data.val == stupid_true) + cl->options |= OPTION_INDIRECT; + } + + if((cfg = get_config_val(cl->config, config_tcponly))) + { + if(cfg->data.val == stupid_true) + cl->options |= OPTION_TCPONLY; } + + /* Send him our subnets */ + + for(node = myself->subnet_tree->head; node; node = node->next) + { + subnet = (subnet_t *)node->data; + send_add_subnet(cl, subnet); + } + + /* And send him all the hosts and their subnets we know... */ + + for(node = connection_tree->head; node; node = node->next) + { + p = (connection_t *)node->data; + + if(p != cl && p->status.active) + { + /* Notify others of this connection */ + + if(p->status.meta) + send_add_host(p, cl); + + /* Notify new connection of everything we know */ + + send_add_host(cl, p); + + for(node2 = p->subnet_tree->head; node2; node2 = node2->next) + { + subnet = (subnet_t *)node2->data; + send_add_subnet(cl, subnet); + } + } + } cp - return send_challenge(cl); + return 0; } int send_challenge(connection_t *cl) @@ -267,6 +361,8 @@ int send_challenge(connection_t *cl) char *buffer; int len, x; cp + /* CHECKME: what is most reasonable value for len? */ + len = RSA_size(cl->rsa_key); /* Allocate buffers for the challenge */ @@ -282,32 +378,15 @@ cp RAND_bytes(cl->hischallenge, len); - cl->hischallenge[0] &= 0x7F; /* Somehow if the first byte is more than 0xD0 or something like that, decryption fails... */ - - if(debug_lvl >= DEBUG_SCARY_THINGS) - { - bin2hex(cl->hischallenge, buffer, len); - buffer[len*2] = '\0'; - syslog(LOG_DEBUG, _("Generated random challenge (unencrypted): %s"), buffer); - } - - /* Encrypt the random data */ - - if(RSA_public_encrypt(len, cl->hischallenge, buffer, cl->rsa_key, RSA_NO_PADDING) != len) /* NO_PADDING because the message size equals the RSA key size and it is totally random */ - { - syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname); - free(buffer); - return -1; - } cp - /* Convert the encrypted random data to a hexadecimal formatted string */ + /* Convert to hex */ - bin2hex(buffer, buffer, len); + bin2hex(cl->hischallenge, buffer, len); buffer[len*2] = '\0'; +cp /* Send the challenge */ - cl->allow_request = CHAL_REPLY; x = send_request(cl, "%d %s", CHALLENGE, buffer); free(buffer); cp @@ -316,10 +395,10 @@ cp int challenge_h(connection_t *cl) { - char *buffer; + char buffer[MAX_STRING_SIZE]; int len; cp - if(sscanf(cl->buffer, "%*d %as", &buffer) != 1) + if(sscanf(cl->buffer, "%*d "MAX_STRING, buffer) != 1) { syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, cl->hostname); return -1; @@ -332,7 +411,6 @@ cp if(strlen(buffer) != len*2) { syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname); - free(buffer); return -1; } @@ -343,26 +421,10 @@ cp /* Convert the challenge from hexadecimal back to binary */ - hex2bin(buffer,buffer,len); + hex2bin(buffer,cl->mychallenge,len); - /* Decrypt the challenge */ - - if(RSA_private_decrypt(len, buffer, cl->mychallenge, myself->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */ - { - syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname); - free(buffer); - return -1; - } - - if(debug_lvl >= DEBUG_SCARY_THINGS) - { - bin2hex(cl->mychallenge, buffer, len); - buffer[len*2] = '\0'; - syslog(LOG_DEBUG, _("Received random challenge (unencrypted): %s"), buffer); - } + cl->allow_request = CHAL_REPLY; - free(buffer); - /* Rest is done by send_chal_reply() */ cp return send_chal_reply(cl); @@ -389,24 +451,18 @@ cp /* Send the reply */ - if(cl->status.outgoing) - cl->allow_request = ID; - else - cl->allow_request = METAKEY; - cp return send_request(cl, "%d %s", CHAL_REPLY, hash); } int chal_reply_h(connection_t *cl) { - char *hishash; + char hishash[MAX_STRING_SIZE]; char myhash[SHA_DIGEST_LENGTH]; cp - if(sscanf(cl->buffer, "%*d %as", &hishash) != 1) + if(sscanf(cl->buffer, "%*d "MAX_STRING, hishash) != 1) { syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname); - free(hishash); return -1; } @@ -415,7 +471,6 @@ cp if(strlen(hishash) != SHA_DIGEST_LENGTH*2) { syslog(LOG_ERR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->name, cl->hostname); - free(hishash); return -1; } @@ -438,22 +493,14 @@ cp hishash[SHA_DIGEST_LENGTH*2] = '\0'; syslog(LOG_DEBUG, _("Expected challenge reply: %s"), hishash); } - 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. + ack_h() handles the rest from now on. */ cp - if(cl->status.outgoing) - return send_metakey(cl); - else - return send_id(cl); + return ack_h(cl); } int send_metakey(connection_t *cl) @@ -477,8 +524,18 @@ cp RAND_bytes(cl->cipher_outkey, len); - cl->cipher_outkey[0] &= 0x7F; /* FIXME: Somehow if the first byte is more than 0xD0 or something like that, decryption fails... */ - + /* The message we send must be smaller than the modulus of the RSA key. + By definition, for a key of k bits, the following formula holds: + + 2^(k-1) <= modulus < 2^(k) + + Where ^ means "to the power of", not "xor". + This means that to be sure, we must choose our message < 2^(k-1). + This can be done by setting the most significant bit to zero. + */ + + cl->cipher_outkey[0] &= 0x7F; + if(debug_lvl >= DEBUG_SCARY_THINGS) { bin2hex(cl->cipher_outkey, buffer, len); @@ -486,9 +543,14 @@ cp syslog(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), buffer); } - /* Encrypt the random data */ + /* Encrypt the random data - if(RSA_public_encrypt(len, cl->cipher_outkey, buffer, cl->rsa_key, RSA_NO_PADDING) != len) /* NO_PADDING because the message size equals the RSA key size and it is totally random */ + We do not use one of the PKCS padding schemes here. + This is allowed, because we encrypt a totally random string + with a length equal to that of the modulus of the RSA key. + */ + + if(RSA_public_encrypt(len, cl->cipher_outkey, buffer, cl->rsa_key, RSA_NO_PADDING) != len) { syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), cl->name, cl->hostname); free(buffer); @@ -502,25 +564,26 @@ cp /* Send the meta key */ - if(cl->status.outgoing) - cl->allow_request = METAKEY; - else - cl->allow_request = ACK; - x = send_request(cl, "%d %s", METAKEY, buffer); free(buffer); - EVP_EncryptInit(cl->cipher_outctx, EVP_bf_cfb(), cl->cipher_outkey, cl->cipher_outkey + EVP_bf_cfb()->key_len); + /* Further outgoing requests are encrypted with the key we just generated */ + + EVP_EncryptInit(cl->cipher_outctx, EVP_bf_cfb(), + cl->cipher_outkey + len - EVP_bf_cfb()->key_len, + cl->cipher_outkey + len - EVP_bf_cfb()->key_len - EVP_bf_cfb()->iv_len); + + cl->status.encryptout = 1; cp return x; } int metakey_h(connection_t *cl) { - char *buffer; + char buffer[MAX_STRING_SIZE]; int len; cp - if(sscanf(cl->buffer, "%*d %as", &buffer) != 1) + if(sscanf(cl->buffer, "%*d "MAX_STRING, buffer) != 1) { syslog(LOG_ERR, _("Got bad METAKEY from %s (%s)"), cl->name, cl->hostname); return -1; @@ -533,7 +596,6 @@ cp if(strlen(buffer) != len*2) { syslog(LOG_ERR, _("Intruder: wrong meta key length from %s (%s)"), cl->name, cl->hostname); - free(buffer); return -1; } @@ -554,7 +616,6 @@ cp if(RSA_private_decrypt(len, buffer, cl->cipher_inkey, myself->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */ { syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), cl->name, cl->hostname); - free(buffer); return -1; } @@ -565,101 +626,17 @@ cp syslog(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), buffer); } - free(buffer); + /* All incoming requests will now be encrypted. */ - EVP_DecryptInit(cl->cipher_inctx, EVP_bf_cfb(), cl->cipher_inkey, cl->cipher_inkey + EVP_bf_cfb()->key_len); + EVP_DecryptInit(cl->cipher_inctx, EVP_bf_cfb(), + cl->cipher_inkey + len - EVP_bf_cfb()->key_len, + cl->cipher_inkey + len - EVP_bf_cfb()->key_len - EVP_bf_cfb()->iv_len); -cp - if(cl->status.outgoing) - return send_ack(cl); - else - return send_metakey(cl); -} - -int send_ack(connection_t *cl) -{ - int x; -cp - if(cl->status.outgoing) - cl->allow_request = ACK; - - setup_vpn_connection(cl); - - x = send_request(cl, "%d", ACK); - cl->status.encryptout = 1; -cp - return x; -} - -int ack_h(connection_t *cl) -{ - connection_t *old, *p; - subnet_t *subnet; - rbl_t *rbl, *rbl2; -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. - */ - - while((old = lookup_id(cl->name))) - { - 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); - - terminate_connection(old); - } - - /* Activate this connection */ - - cl->allow_request = ALL; - cl->status.active = 1; cl->status.decryptin = 1; - cl->nexthop = cl; - cl->cipher_pkttype = EVP_bf_cfb(); - cl->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len; - - if(debug_lvl >= DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname); - -cp - if(!cl->status.outgoing) - send_ack(cl); - /* Send him our subnets */ - - RBL_FOREACH(myself->subnet_tree, rbl) - { - subnet = (subnet_t *)rbl->data; - send_add_subnet(cl, subnet); - } - /* And send him all the hosts and their subnets we know... */ - - RBL_FOREACH(connection_tree, rbl) - { - p = (connection_t *)rbl->data; - - if(p != cl && p->status.active) - { - /* Notify others of this connection */ - - if(p->status.meta) - send_add_host(p, cl); - - /* Notify new connection of everything we know */ - - send_add_host(cl, p); - - RBL_FOREACH(p->subnet_tree, rbl2) - { - subnet = (subnet_t *)rbl2->data; - send_add_subnet(cl, subnet); - } - } - } + cl->allow_request = CHALLENGE; cp - return 0; + return send_challenge(cl); } /* Address and subnet information exchange */ @@ -668,9 +645,15 @@ int send_add_subnet(connection_t *cl, subnet_t *subnet) { int x; char *netstr; + char *owner; cp + if((cl->options | myself->options | subnet->owner->options) & OPTION_INDIRECT) + owner = myself->name; + else + owner = subnet->owner->name; + x = send_request(cl, "%d %s %s", ADD_SUBNET, - subnet->owner->name, netstr = net2str(subnet)); + owner, netstr = net2str(subnet)); free(netstr); cp return x; @@ -678,16 +661,15 @@ cp int add_subnet_h(connection_t *cl) { - char *subnetstr; - char *name; + char subnetstr[MAX_STRING_SIZE]; + char name[MAX_STRING_SIZE]; connection_t *owner, *p; subnet_t *subnet; - rbl_t *rbl; + avl_node_t *node; cp - if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 2) + if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, name, subnetstr) != 2) { syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s)"), cl->name, cl->hostname); - free(name); free(subnetstr); return -1; } @@ -696,7 +678,6 @@ cp if(check_id(name)) { syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname); - free(name); free(subnetstr); return -1; } @@ -705,19 +686,15 @@ cp if(!(subnet = str2net(subnetstr))) { syslog(LOG_ERR, _("Got bad ADD_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 ADD_SUBNET from %s (%s) for ourself, restarting"), cl->name, cl->hostname); - free(name); sighup = 1; return 0; } @@ -728,18 +705,6 @@ cp { syslog(LOG_ERR, _("Got ADD_SUBNET for %s from %s (%s) which is not in our connection list"), name, cl->name, cl->hostname); - cp_trace(); - dump_connection_list(); - { - connection_t cl; - rbl_t *rbl; - cl.name = name; - rbl = rbl_search_rbl(connection_tree, &cl); - syslog(LOG_ERR, "rbl_search_rbl: %p", rbl); - if(rbl) - syslog(LOG_ERR, "rbl->data->name: %s", ((connection_t *)rbl->data)->name); - } - free(name); return -1; } @@ -749,9 +714,9 @@ cp /* Tell the rest */ - RBL_FOREACH(connection_tree, rbl) + for(node = connection_tree->head; node; node = node->next) { - p = (connection_t *)rbl->data; + p = (connection_t *)node->data; if(p->status.meta && p->status.active && p!= cl) send_add_subnet(p, subnet); } @@ -763,9 +728,14 @@ int send_del_subnet(connection_t *cl, subnet_t *subnet) { int x; char *netstr; + char *owner; cp - netstr = net2str(subnet); - x = send_request(cl, "%d %s %s", DEL_SUBNET, subnet->owner->name, netstr); + if(cl->options & OPTION_INDIRECT) + owner = myself->name; + else + owner = subnet->owner->name; + + x = send_request(cl, "%d %s %s", DEL_SUBNET, owner, netstr = net2str(subnet)); free(netstr); cp return x; @@ -773,16 +743,15 @@ cp int del_subnet_h(connection_t *cl) { - char *subnetstr; - char *name; + char subnetstr[MAX_STRING_SIZE]; + char name[MAX_STRING_SIZE]; connection_t *owner, *p; subnet_t *subnet; - rbl_t *rbl; + avl_node_t *node; cp - if(sscanf(cl->buffer, "%*d %as %as", &name, &subnetstr) != 3) + if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, name, subnetstr) != 3) { syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s)"), cl->name, cl->hostname); - free(name); free(subnetstr); return -1; } @@ -791,7 +760,6 @@ cp 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; } @@ -800,7 +768,6 @@ cp if(!(subnet = str2net(subnetstr))) { syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname); - free(name); free(subnetstr); return -1; } @@ -812,7 +779,6 @@ cp { syslog(LOG_ERR, _("Warning: got DEL_SUBNET from %s (%s) for ourself, restarting"), cl->name, cl->hostname); - free(name); sighup = 1; return 0; } @@ -823,7 +789,6 @@ cp { 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; } @@ -833,9 +798,9 @@ cp /* Tell the rest */ - RBL_FOREACH(connection_tree, rbl) + for(node = connection_tree->head; node; node = node->next) { - p = (connection_t *)rbl->data; + p = (connection_t *)node->data; if(p->status.meta && p->status.active && p!= cl) send_del_subnet(p, subnet); } @@ -848,18 +813,22 @@ cp int send_add_host(connection_t *cl, connection_t *other) { cp - return send_request(cl, "%d %s %lx:%d %lx", ADD_HOST, + if(!((cl->options | myself->options | other->options) & OPTION_INDIRECT)) + return send_request(cl, "%d %s %lx:%d %lx", ADD_HOST, other->name, other->address, other->port, other->options); + else + return 0; } int add_host_h(connection_t *cl) { connection_t *old, *new, *p; - rbl_t *rbl; + char name[MAX_STRING_SIZE]; + avl_node_t *node; cp new = new_connection(); - if(sscanf(cl->buffer, "%*d %as %lx:%d %lx", &new->name, &new->address, &new->port, &new->options) != 4) + if(sscanf(cl->buffer, "%*d "MAX_STRING" %lx:%hd %lx", name, &new->address, &new->port, &new->options) != 4) { syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->name, cl->hostname); return -1; @@ -867,7 +836,7 @@ cp /* Check if identity is a valid name */ - if(check_id(new->name)) + if(check_id(name)) { syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); free_connection(new); @@ -876,7 +845,7 @@ cp /* Check if somebody tries to add ourself */ - if(!strcmp(new->name, myself->name)) + if(!strcmp(name, myself->name)) { syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname); sighup = 1; @@ -890,13 +859,13 @@ cp /* Check if the new host already exists in the connnection list */ - if((old = lookup_id(new->name))) + if((old = lookup_id(name))) { if((new->address == old->address) && (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); + old->name, old->hostname, name, new->hostname); free_connection(new); return 0; } @@ -912,14 +881,15 @@ cp /* Hook it up into the connection */ + new->name = xstrdup(name); connection_add(new); id_add(new); /* Tell the rest about the new host */ - RBL_FOREACH(connection_tree, rbl) + for(node = connection_tree->head; node; node = node->next) { - p = (connection_t *)rbl->data; + p = (connection_t *)node->data; if(p->status.meta && p->status.active && p!=cl) send_add_host(p, new); } @@ -928,14 +898,8 @@ cp new->nexthop = cl; new->status.active = 1; - new->cipher_pkttype = EVP_bf_cfb(); + new->cipher_pkttype = EVP_bf_cbc(); new->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len; - - /* Okay this is a bit ugly... it would be better to setup UDP sockets dynamically, or - * perhaps just one UDP socket... but then again, this has benefits too... - */ - - setup_vpn_connection(new); cp return 0; } @@ -943,20 +907,23 @@ cp int send_del_host(connection_t *cl, connection_t *other) { cp - return send_request(cl, "%d %s %lx:%d %lx", DEL_HOST, + if(!((cl->options | myself->options) & OPTION_INDIRECT)) + return send_request(cl, "%d %s %lx:%d %lx", DEL_HOST, other->name, other->address, other->port, other->options); + else + return 0; } int del_host_h(connection_t *cl) { - char *name; - ip_t address; + char name[MAX_STRING_SIZE]; + ipv4_t address; port_t port; long int options; connection_t *old, *p; - rbl_t *rbl; + avl_node_t *node; cp - if(sscanf(cl->buffer, "%*d %as %lx:%d %lx", &name, &address, &port, &options) != 4) + if(sscanf(cl->buffer, "%*d "MAX_STRING" %lx:%hd %lx", name, &address, &port, &options) != 4) { syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), cl->name, cl->hostname); @@ -968,7 +935,6 @@ cp if(check_id(name)) { syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); - free(name); return -1; } @@ -978,7 +944,6 @@ cp { syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname); - free(name); sighup = 1; return 0; } @@ -989,7 +954,6 @@ cp { 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; } @@ -1008,9 +972,9 @@ cp /* Tell the rest about the new host */ - RBL_FOREACH(connection_tree, rbl) + for(node = connection_tree->head; node; node = node->next) { - p = (connection_t *)rbl->data; + p = (connection_t *)node->data; if(p->status.meta && p->status.active && p!=cl) send_del_host(p, old); } @@ -1032,9 +996,9 @@ cp int status_h(connection_t *cl) { int statusno; - char *statusstring; + char statusstring[MAX_STRING_SIZE]; cp - if(sscanf(cl->buffer, "%*d %d %as", &statusno, &statusstring) != 2) + if(sscanf(cl->buffer, "%*d %d "MAX_STRING, &statusno, statusstring) != 2) { syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), cl->name, cl->hostname); @@ -1048,24 +1012,23 @@ cp } cp - free(statusstring); return 0; } -int send_error(connection_t *cl, int errno, char *errstring) +int send_error(connection_t *cl, int err, char *errstring) { cp if(!errstring) - errstring = strerror(errno); - return send_request(cl, "%d %d %s", ERROR, errno, errstring); + errstring = strerror(err); + return send_request(cl, "%d %d %s", ERROR, err, errstring); } int error_h(connection_t *cl) { - int errno; - char *errorstring; + int err; + char errorstring[MAX_STRING_SIZE]; cp - if(sscanf(cl->buffer, "%*d %d %as", &errno, &errorstring) != 2) + if(sscanf(cl->buffer, "%*d %d "MAX_STRING, &err, errorstring) != 2) { syslog(LOG_ERR, _("Got bad ERROR from %s (%s)"), cl->name, cl->hostname); @@ -1075,10 +1038,9 @@ cp if(debug_lvl >= DEBUG_ERROR) { syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"), - cl->name, cl->hostname, strerror(errno), errorstring); + cl->name, cl->hostname, strerror(err), errorstring); } - free(errorstring); terminate_connection(cl); cp return 0; @@ -1098,15 +1060,17 @@ cp return 0; } -/* Keepalive routines - FIXME: needs a closer look */ - int send_ping(connection_t *cl) { + char salt[SALTLEN*2+1]; cp cl->status.pinged = 1; cl->last_ping_time = time(NULL); + RAND_bytes(salt, SALTLEN); + bin2hex(salt, salt, SALTLEN); + salt[SALTLEN*2] = '\0'; cp - return send_request(cl, "%d", PING); + return send_request(cl, "%d %s", PING, salt); } int ping_h(connection_t *cl) @@ -1117,8 +1081,13 @@ cp int send_pong(connection_t *cl) { + char salt[SALTLEN*2+1]; +cp + RAND_bytes(salt, SALTLEN); + bin2hex(salt, salt, SALTLEN); + salt[SALTLEN*2] = '\0'; cp - return send_request(cl, "%d", PONG); + return send_request(cl, "%d %s", PONG, salt); } int pong_h(connection_t *cl) @@ -1134,13 +1103,21 @@ cp int send_key_changed(connection_t *from, connection_t *cl) { connection_t *p; - rbl_t *rbl; + avl_node_t *node; cp - RBL_FOREACH(connection_tree, rbl) + /* Only send this message if some other daemon requested our key previously. + This reduces unnecessary key_changed broadcasts. + */ + + if(from==myself && !mykeyused) + return 0; + + for(node = connection_tree->head; node; node = node->next) { - p = (connection_t *)rbl->data; + p = (connection_t *)node->data; if(p != cl && p->status.meta && p->status.active) - send_request(p, "%d %s", KEY_CHANGED, from->name); + if(!(p->options & OPTION_INDIRECT) || from == myself) + send_request(p, "%d %s", KEY_CHANGED, from->name); } cp return 0; @@ -1148,10 +1125,10 @@ cp int key_changed_h(connection_t *cl) { - char *from_id; + char from_id[MAX_STRING_SIZE]; connection_t *from; cp - if(sscanf(cl->buffer, "%*d %as", &from_id) != 1) + if(sscanf(cl->buffer, "%*d "MAX_STRING, from_id) != 1) { syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), cl->name, cl->hostname); @@ -1162,16 +1139,14 @@ cp { 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); + if(!(from->options | cl->options | myself->options) & OPTION_INDIRECT) + send_key_changed(from, cl); cp return 0; } @@ -1185,11 +1160,12 @@ cp int req_key_h(connection_t *cl) { - char *from_id, *to_id; + char from_id[MAX_STRING_SIZE]; + char to_id[MAX_STRING_SIZE]; connection_t *from, *to; char pktkey[129]; cp - if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2) + if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, from_id, to_id) != 2) { syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), cl->name, cl->hostname); @@ -1200,17 +1176,17 @@ cp { 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; } /* Check if this key request is for us */ - if(!strcmp(to_id, myself->name)) + if(!strcmp(to_id, myself->name)) /* Yes, send our own key back */ { bin2hex(myself->cipher_pktkey, pktkey, myself->cipher_pktkeylength); pktkey[myself->cipher_pktkeylength*2] = '\0'; send_ans_key(myself, from, pktkey); + mykeyused = 1; } else { @@ -1218,7 +1194,6 @@ cp { 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; } @@ -1232,7 +1207,6 @@ cp send_req_key(from, to); } - free(from_id); free(to_id); cp return 0; } @@ -1246,11 +1220,13 @@ cp int ans_key_h(connection_t *cl) { - char *from_id, *to_id, *pktkey; + char from_id[MAX_STRING_SIZE]; + char to_id[MAX_STRING_SIZE]; + char pktkey[MAX_STRING_SIZE]; int keylength; connection_t *from, *to; cp - if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &pktkey) != 3) + if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING, from_id, to_id, pktkey) != 3) { syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), cl->name, cl->hostname); @@ -1261,7 +1237,6 @@ cp { 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(pktkey); return -1; } @@ -1273,7 +1248,6 @@ cp { syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key length"), cl->name, cl->hostname, from->name); - free(from_id); free(to_id); free(pktkey); return -1; } @@ -1285,7 +1259,6 @@ cp { 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); return -1; } send_ans_key(from, to, pktkey); @@ -1296,15 +1269,46 @@ cp if(from->cipher_pktkey) free(from->cipher_pktkey); + from->cipher_pktkey = xstrdup(pktkey); keylength /= 2; - hex2bin(pktkey, pktkey, keylength); - pktkey[keylength] = '\0'; - from->cipher_pktkey = pktkey; + hex2bin(from->cipher_pktkey, from->cipher_pktkey, keylength); + from->cipher_pktkey[keylength] = '\0'; from->status.validkey = 1; from->status.waitingforkey = 0; - - free(from_id); free(to_id); + + flush_queue(from); +cp + return 0; +} + +int send_tcppacket(connection_t *cl, vpn_packet_t *packet) +{ + int x; +cp + /* Evil hack. */ + + x = send_request(cl->nexthop, "%d %hd", PACKET, packet->len); + + if(x) + return x; +cp + return send_meta(cl, packet->data, packet->len); +} + +int tcppacket_h(connection_t *cl) +{ + short int len; +cp + if(sscanf(cl->buffer, "%*d %hd", &len) != 1) + { + syslog(LOG_ERR, _("Got bad PACKET from %s (%s)"), cl->name, cl->hostname); + return -1; + } + + /* Set reqlen to len, this will tell receive_meta() that a tcppacket is coming. */ + + cl->tcplen = len; cp return 0; } @@ -1312,23 +1316,25 @@ cp /* Jumptable for the request handlers */ int (*request_handlers[])(connection_t*) = { - id_h, challenge_h, chal_reply_h, metakey_h, ack_h, + id_h, metakey_h, challenge_h, chal_reply_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, + tcppacket_h, }; /* Request names */ char (*request_name[]) = { - "ID", "CHALLENGE", "CHAL_REPLY", "METAKEY", "ACK", + "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY", "STATUS", "ERROR", "TERMREQ", "PING", "PONG", "ADD_HOST", "DEL_HOST", "ADD_SUBNET", "DEL_SUBNET", "KEY_CHANGED", "REQ_KEY", "ANS_KEY", + "PACKET", }; /* Status strings */