X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=625c7094115d1924ef845168b31e5f2fcbdb2aeb;hp=d9b10dfdd35f1a309490a8fad261311ef41d2802;hb=156ec676525ed789364b7a77926dd0717d0cf5d7;hpb=cea3d8f3056d3c6aaaef473443240b8470c8ea2d diff --git a/src/protocol.c b/src/protocol.c index d9b10dfd..625c7094 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 1.28.4.51 2000/10/29 10:39:08 guus Exp $ + $Id: protocol.c,v 1.28.4.86 2001/03/13 21:33:31 guus Exp $ */ #include "config.h" @@ -30,22 +30,41 @@ #include #include #include +#include +#include #include #include +#include +#include #include -#include -#include -#include +#ifdef HAVE_OPENSSL_SHA_H +# include +#else +# include +#endif + +#ifdef HAVE_OPENSSL_RAND_H +# include +#else +# include +#endif + +#ifdef HAVE_OPENSSL_EVP_H +# include +#else +# include +#endif + #include "conf.h" #include "net.h" #include "netutl.h" #include "protocol.h" #include "meta.h" -#include "connlist.h" +#include "connection.h" #include "system.h" @@ -56,21 +75,23 @@ 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(conn_list_t *cl, const char *format, ...) +int send_request(connection_t *cl, const char *format, ...) { va_list args; char buffer[MAXBUFSIZE]; 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); @@ -92,13 +113,13 @@ cp return send_meta(cl, buffer, len); } -int receive_request(conn_list_t *cl) +int receive_request(connection_t *cl) { int request; 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); @@ -145,8 +166,8 @@ cp send_challenge(R) send_chal_reply(H) --------------------------------------- - Any negotations about the meta protocol - encryption go here(u). + send_metakey(R) + send_metakey(R) --------------------------------------- send_ack(u) send_ack(u) @@ -158,25 +179,26 @@ cp (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. + 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. */ -int send_id(conn_list_t *cl) +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); } -int id_h(conn_list_t *cl) +int id_h(connection_t *cl) { - conn_list_t *old; - config_t *cfg; + connection_t *old; + 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; @@ -193,14 +215,18 @@ 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 */ + + cl->name = xstrdup(name); /* Load information about peer */ -cp + if(read_host_config(cl)) { syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->name); @@ -211,7 +237,7 @@ cp connection list. If so, we are probably making a loop, which is not desirable. */ -cp + if(cl->status.outgoing) { if((old = lookup_id(cl->name))) @@ -224,27 +250,117 @@ cp return 0; } } -cp - if((cfg = get_config_val(cl->config, publickey))) + + /* Now we can add the name to the id tree */ + + id_add(cl); + + /* 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; + avl_insert_node(connection_tree, node); + + /* 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. + */ + + 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); + +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(conn_list_t *cl) +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 */ @@ -256,52 +372,31 @@ cp cl->hischallenge = xmalloc(len); cp - /* Seed the PRNG with urandom (can't afford to block) */ - - RAND_load_file("/dev/urandom", 1024); - /* Copy random data to the buffer */ 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 return x; } -int challenge_h(conn_list_t *cl) +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; @@ -314,7 +409,6 @@ cp if(strlen(buffer) != len*2) { syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname); - free(buffer); return -1; } @@ -325,32 +419,16 @@ 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); } -int send_chal_reply(conn_list_t *cl) +int send_chal_reply(connection_t *cl) { char hash[SHA_DIGEST_LENGTH*2+1]; cp @@ -371,24 +449,18 @@ cp /* 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 chal_reply_h(conn_list_t *cl) +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; } @@ -397,7 +469,6 @@ 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; } @@ -420,117 +491,183 @@ 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_ack(cl); - else - return send_id(cl); + return ack_h(cl); } -int send_ack(conn_list_t *cl) +int send_metakey(connection_t *cl) { + char *buffer; + int len, x; cp - if(cl->status.outgoing) - cl->allow_request = ACK; + len = RSA_size(cl->rsa_key); + + /* Allocate buffers for the meta key */ + + buffer = xmalloc(len*2+1); + + if(!cl->cipher_outkey) + cl->cipher_outkey = xmalloc(len); + + if(!cl->cipher_outctx) + cl->cipher_outctx = xmalloc(sizeof(*cl->cipher_outctx)); cp - return send_request(cl, "%d", ACK); + /* Copy random data to the buffer */ + + RAND_bytes(cl->cipher_outkey, len); + + /* 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); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), buffer); + } + + /* Encrypt the random data + + 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); + return -1; + } +cp + /* Convert the encrypted random data to a hexadecimal formatted string */ + + bin2hex(buffer, buffer, len); + buffer[len*2] = '\0'; + + /* Send the meta key */ + + x = send_request(cl, "%d %s", METAKEY, buffer); + free(buffer); + + /* 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 ack_h(conn_list_t *cl) +int metakey_h(connection_t *cl) { - conn_list_t *old, *p; - subnet_t *s; + char buffer[MAX_STRING_SIZE]; + int len; 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(sscanf(cl->buffer, "%*d "MAX_STRING, buffer) != 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); + syslog(LOG_ERR, _("Got bad METAKEY from %s (%s)"), cl->name, cl->hostname); + return -1; + } - terminate_connection(old); + len = RSA_size(myself->rsa_key); + + /* Check if the length of the meta key is all right */ + + if(strlen(buffer) != len*2) + { + syslog(LOG_ERR, _("Intruder: wrong meta key length from %s (%s)"), cl->name, cl->hostname); + return -1; } - /* Activate this connection */ + /* Allocate buffers for the meta key */ - cl->allow_request = ALL; - cl->status.active = 1; - cl->nexthop = cl; - cl->cipher_pkttype = EVP_bf_cbc(); + if(!cl->cipher_inkey) + cl->cipher_inkey = xmalloc(len); - if(debug_lvl >= DEBUG_CONNECTIONS) - syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->name, cl->hostname); + if(!cl->cipher_inctx) + cl->cipher_inctx = xmalloc(sizeof(*cl->cipher_inctx)); -cp - if(!cl->status.outgoing) - send_ack(cl); + /* Convert the challenge from hexadecimal back to binary */ - /* Send him our subnets */ - - for(s = myself->subnets; s; s = s->next) - send_add_subnet(cl, s); + hex2bin(buffer,buffer,len); - /* And send him all the hosts and their subnets we know... */ + /* Decrypt the meta key */ - for(p = conn_list; p; p = p->next) - if(p != cl && p->status.active) - { - /* Notify others of this connection */ - - if(p->status.meta) - send_add_host(p, cl); + 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); + return -1; + } + + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(cl->cipher_inkey, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), buffer); + } - /* Notify new connection of everything we know */ + /* All incoming requests will now be encrypted. */ - send_add_host(cl, p); - - for(s = p->subnets; s; s = s->next) - send_add_subnet(cl, s); - } + 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); + + cl->status.decryptin = 1; + + cl->allow_request = CHALLENGE; cp - return 0; + return send_challenge(cl); } /* Address and subnet information exchange */ -int send_add_subnet(conn_list_t *cl, subnet_t *subnet) +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; } -int add_subnet_h(conn_list_t *cl) +int add_subnet_h(connection_t *cl) { - char *subnetstr; - char *name; - conn_list_t *owner, *p; + char subnetstr[MAX_STRING_SIZE]; + char name[MAX_STRING_SIZE]; + connection_t *owner, *p; subnet_t *subnet; + 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; } @@ -539,7 +676,6 @@ 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; } @@ -548,19 +684,15 @@ 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; } @@ -571,7 +703,6 @@ cp { syslog(LOG_ERR, _("Got ADD_SUBNET for %s from %s (%s) which is not in our connection list"), name, cl->name, cl->hostname); - free(name); return -1; } @@ -581,36 +712,44 @@ cp /* Tell the rest */ - for(p = conn_list; p; p = p->next) - if(p->status.meta && p->status.active && p!= cl) - send_add_subnet(p, subnet); + for(node = connection_tree->head; node; node = node->next) + { + p = (connection_t *)node->data; + if(p->status.meta && p->status.active && p!= cl) + send_add_subnet(p, subnet); + } cp return 0; } -int send_del_subnet(conn_list_t *cl, subnet_t *subnet) +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; } -int del_subnet_h(conn_list_t *cl) +int del_subnet_h(connection_t *cl) { - char *subnetstr; - char *name; - conn_list_t *owner, *p; + char subnetstr[MAX_STRING_SIZE]; + char name[MAX_STRING_SIZE]; + connection_t *owner, *p; subnet_t *subnet; + 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; } @@ -619,7 +758,6 @@ 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; } @@ -628,7 +766,6 @@ 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; } @@ -640,7 +777,6 @@ cp { syslog(LOG_ERR, _("Warning: got DEL_SUBNET from %s (%s) for ourself, restarting"), cl->name, cl->hostname); - free(name); sighup = 1; return 0; } @@ -651,7 +787,6 @@ 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; } @@ -661,30 +796,37 @@ cp /* Tell the rest */ - for(p = conn_list; p; p = p->next) - if(p->status.meta && p->status.active && p!= cl) - send_del_subnet(p, subnet); + for(node = connection_tree->head; node; node = node->next) + { + p = (connection_t *)node->data; + if(p->status.meta && p->status.active && p!= cl) + send_del_subnet(p, subnet); + } cp return 0; } /* New and closed connections notification */ -int send_add_host(conn_list_t *cl, conn_list_t *other) +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(conn_list_t *cl) +int add_host_h(connection_t *cl) { - conn_list_t *old, *new; - conn_list_t *p; + connection_t *old, *new, *p; + char name[MAX_STRING_SIZE]; + avl_node_t *node; cp - new = new_conn_list(); + 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; @@ -692,37 +834,37 @@ 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_conn_list(new); + free_connection(new); return -1; } /* 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; - free_conn_list(new); + free_connection(new); return 0; } - /* Fill in more of the new conn_list structure */ + /* Fill in more of the new connection structure */ new->hostname = hostlookup(htonl(new->address)); /* 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); - free_conn_list(new); + old->name, old->hostname, name, new->hostname); + free_connection(new); return 0; } else @@ -735,41 +877,51 @@ cp } } - /* Hook it up into the conn_list */ + /* Hook it up into the connection */ - conn_list_add(new); + new->name = xstrdup(name); + connection_add(new); + id_add(new); /* Tell the rest about the new host */ - for(p = conn_list; p; p = p->next) - if(p->status.meta && p->status.active && p!=cl) - send_add_host(p, new); + for(node = connection_tree->head; node; node = node->next) + { + p = (connection_t *)node->data; + if(p->status.meta && p->status.active && p!=cl) + send_add_host(p, new); + } - /* Fill in rest of conn_list structure */ + /* Fill in rest of connection structure */ new->nexthop = cl; new->status.active = 1; - + new->cipher_pkttype = EVP_bf_cbc(); + new->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len; cp return 0; } -int send_del_host(conn_list_t *cl, conn_list_t *other) +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(conn_list_t *cl) +int del_host_h(connection_t *cl) { - char *name; + char name[MAX_STRING_SIZE]; ip_t address; port_t port; long int options; - conn_list_t *old, *p; + connection_t *old, *p; + 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); @@ -781,7 +933,6 @@ 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; } @@ -791,7 +942,6 @@ cp { syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname); - free(name); sighup = 1; return 0; } @@ -802,7 +952,6 @@ 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; } @@ -821,16 +970,19 @@ cp /* Tell the rest about the new host */ - for(p = conn_list; p; p = p->next) - if(p->status.meta && p->status.active && p!=cl) - send_del_host(p, old); + for(node = connection_tree->head; node; node = node->next) + { + p = (connection_t *)node->data; + if(p->status.meta && p->status.active && p!=cl) + send_del_host(p, old); + } cp return 0; } /* Status and error notification routines */ -int send_status(conn_list_t *cl, int statusno, char *statusstring) +int send_status(connection_t *cl, int statusno, char *statusstring) { cp if(!statusstring) @@ -839,12 +991,12 @@ cp return send_request(cl, "%d %d %s", STATUS, statusno, statusstring); } -int status_h(conn_list_t *cl) +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); @@ -858,24 +1010,23 @@ cp } cp - free(statusstring); return 0; } -int send_error(conn_list_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(conn_list_t *cl) +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); @@ -885,22 +1036,21 @@ 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; } -int send_termreq(conn_list_t *cl) +int send_termreq(connection_t *cl) { cp return send_request(cl, "%d", TERMREQ); } -int termreq_h(conn_list_t *cl) +int termreq_h(connection_t *cl) { cp terminate_connection(cl); @@ -908,57 +1058,59 @@ cp return 0; } -/* Keepalive routines - FIXME: needs a closer look */ - -int send_ping(conn_list_t *cl) +int send_ping(connection_t *cl) { +cp cl->status.pinged = 1; + cl->last_ping_time = time(NULL); cp return send_request(cl, "%d", PING); } -int ping_h(conn_list_t *cl) +int ping_h(connection_t *cl) { cp return send_pong(cl); } -int send_pong(conn_list_t *cl) +int send_pong(connection_t *cl) { cp return send_request(cl, "%d", PONG); } -int pong_h(conn_list_t *cl) +int pong_h(connection_t *cl) { cp - cl->status.got_pong = 1; + cl->status.pinged = 0; cp return 0; } /* Key exchange */ -int send_key_changed(conn_list_t *from, conn_list_t *cl) +int send_key_changed(connection_t *from, connection_t *cl) { - conn_list_t *p; + connection_t *p; + avl_node_t *node; cp - for(p = conn_list; p != NULL; p = p->next) + for(node = connection_tree->head; node; node = node->next) { - if(p!=cl && p->status.meta && p->status.active) - send_request(p, "%d %s", KEY_CHANGED, - from->name); + p = (connection_t *)node->data; + if(p != cl && p->status.meta && p->status.active) + if(!(p->options & OPTION_INDIRECT) || from == myself) + send_request(p, "%d %s", KEY_CHANGED, from->name); } cp return 0; } -int key_changed_h(conn_list_t *cl) +int key_changed_h(connection_t *cl) { - char *from_id; - conn_list_t *from; + 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); @@ -969,34 +1121,33 @@ 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; } -int send_req_key(conn_list_t *from, conn_list_t *to) +int send_req_key(connection_t *from, connection_t *to) { cp return send_request(to->nexthop, "%d %s %s", REQ_KEY, from->name, to->name); } -int req_key_h(conn_list_t *cl) +int req_key_h(connection_t *cl) { - char *from_id, *to_id; - conn_list_t *from, *to; + 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); @@ -1007,7 +1158,6 @@ 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; } @@ -1015,8 +1165,8 @@ cp if(!strcmp(to_id, myself->name)) { - bin2hex(myself->cipher_pktkey, pktkey, 64); - pktkey[128] = 0; + bin2hex(myself->cipher_pktkey, pktkey, myself->cipher_pktkeylength); + pktkey[myself->cipher_pktkeylength*2] = '\0'; send_ans_key(myself, from, pktkey); } else @@ -1025,31 +1175,39 @@ 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; } - send_req_key(from, to); + + if(to->status.validkey) /* Proxy keys */ + { + bin2hex(to->cipher_pktkey, pktkey, to->cipher_pktkeylength); + pktkey[to->cipher_pktkeylength*2] = '\0'; + send_ans_key(to, from, pktkey); + } + else + send_req_key(from, to); } - free(from_id); free(to_id); cp return 0; } -int send_ans_key(conn_list_t *from, conn_list_t *to, char *pktkey) +int send_ans_key(connection_t *from, connection_t *to, char *pktkey) { cp return send_request(to->nexthop, "%d %s %s %s", ANS_KEY, from->name, to->name, pktkey); } -int ans_key_h(conn_list_t *cl) +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; - conn_list_t *from, *to; + 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); @@ -1060,70 +1218,128 @@ 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; } - /* Update origin's packet key */ + /* Check correctness of packet key */ keylength = strlen(pktkey); - if((keylength%2)!=0 || (keylength <= 0)) + if(keylength != from->cipher_pktkeylength*2) { - syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key"), + 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; } + /* Forward it if necessary */ + + if(strcmp(to_id, myself->name)) + { + 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); + return -1; + } + send_ans_key(from, to, pktkey); + } + + /* Update our copy of the origin's packet key */ + 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; - - if(strcmp(to_id, myself->name)) + + flush_queue(from); +cp + return 0; +} + +int send_tcppacket(connection_t *cl, vpn_packet_t *packet) +{ + int x; +cp + x = send_request(cl->nexthop, "%d %hd", PACKET, packet->len); + + if(x) + return x; + + return send_meta(cl->nexthop, packet->data, packet->len); +} + +int tcppacket_h(connection_t *cl) +{ + vpn_packet_t packet; + char *p; + int todo, x; +cp + if(sscanf(cl->buffer, "%*d %hd", &packet.len) != 1) { - if(!(to = lookup_id(to_id))) + syslog(LOG_ERR, _("Got bad PACKET from %s (%s)"), cl->name, cl->hostname); + return -1; + } + + /* Evil hack. */ + + p = packet.data; + todo = packet.len; + + while(todo) + { + x = read(cl->meta_socket, p, todo); + + if(x<=0) { - 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); + if(x==0) + syslog(LOG_NOTICE, _("Connection closed by %s (%s)"), cl->name, cl->hostname); + else + if(errno==EINTR || errno==EAGAIN) /* FIXME: select() or poll() or reimplement this evil hack */ + continue; + else + syslog(LOG_ERR, _("Error during reception of PACKET from %s (%s): %m"), cl->name, cl->hostname); + return -1; } - send_ans_key(from, to, pktkey); + + todo -= x; + p += x; } - free(from_id); free(to_id); + receive_packet(cl, &packet); cp return 0; } /* Jumptable for the request handlers */ -int (*request_handlers[])(conn_list_t*) = { - id_h, challenge_h, chal_reply_h, ack_h, +int (*request_handlers[])(connection_t*) = { + 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", "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 */