X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol.c;h=85a4047c2c9360886a96233504588b30209987ae;hp=3c20f3b2762a8f06efedeafbee2a85cdf519eb3d;hb=e924096f62655d711cd2d114a8d1ef0fecbb593b;hpb=1a1ebefd572c18d6af187750847b024ce07551ae diff --git a/src/protocol.c b/src/protocol.c index 3c20f3b2..85a4047c 100644 --- a/src/protocol.c +++ b/src/protocol.c @@ -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 1.28.4.19 2000/06/30 21:03:51 guus Exp $ + $Id: protocol.c,v 1.28.4.71 2001/01/05 23:53:51 guus Exp $ */ #include "config.h" @@ -30,946 +30,1267 @@ #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 "encr.h" #include "net.h" #include "netutl.h" #include "protocol.h" +#include "meta.h" +#include "connection.h" #include "system.h" -char buffer[MAXBUFSIZE+1]; -int buflen; - -/* Outgoing request routines */ - -int send_ack(conn_list_t *cl) +int check_id(char *id) { -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending ACK to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + int i; - buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", ACK); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %d:%d: %m"), __FILE__, __LINE__); + for (i = 0; i < strlen(id); i++) + if(!isalnum(id[i]) && id[i] != '_') return -1; - } -cp + return 0; } -int send_termreq(conn_list_t *cl) +/* Generic request routines - takes care of logging and error + detection as well */ + +int send_request(connection_t *cl, const char *format, ...) { + va_list args; + char buffer[MAXBUFSIZE]; + int len, request; + cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending TERMREQ to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + /* 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, format); + len = vsnprintf(buffer, MAXBUFSIZE, format, args); + request = va_arg(args, int); + va_end(args); - if(write(cl->meta_socket, buffer, buflen) < 0) + if(len < 0 || len > MAXBUFSIZE-1) { - 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; } + + len++; + + 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, len); } -int send_timeout(conn_list_t *cl) +int receive_request(connection_t *cl) { -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending TIMEOUT to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + int request; +cp + if(sscanf(cl->buffer, "%d", &request) == 1) + { + if((request < 0) || (request > 255) || (request_handlers[request] == NULL)) + { + 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); + } - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", PINGTIMEOUT, myself->vpn_ip); + if((cl->allow_request != ALL) && (cl->allow_request != request)) + { + syslog(LOG_ERR, _("Unauthorized request from %s (%s)"), cl->name, cl->hostname); + return -1; + } - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(request_handlers[request](cl)) + /* Something went wrong. Probably scriptkiddies. Terminate. */ + { + syslog(LOG_ERR, _("Error while processing %s from %s (%s)"), + request_name[request], cl->name, cl->hostname); + return -1; + } + } + else { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); + syslog(LOG_ERR, _("Bogus data received from %s (%s)"), + cl->name, cl->hostname); return -1; } cp return 0; } -int send_del_host(conn_list_t *cl, conn_list_t *new_host) +/* 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. +*/ + +int send_id(connection_t *cl) { cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending DEL_HOST for %s (%s) to %s (%s)"), - new_host->vpn_hostname, new_host->real_hostname, cl->vpn_hostname, cl->real_hostname); - - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", DEL_HOST, new_host->vpn_ip); - - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } + cl->allow_request = CHALLENGE; cp - return 0; + return send_request(cl, "%d %s %d %lx %hd", ID, myself->name, myself->protocol_version, myself->options, myself->port); } -int send_ping(conn_list_t *cl) +int id_h(connection_t *cl) { + connection_t *old; + unsigned short int port; + char name[MAX_STRING_SIZE]; cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending PING to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + 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; + } - 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 - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending PONG to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + /* Check if identity is a valid name */ - buflen = snprintf(buffer, MAXBUFSIZE, "%d\n", PONG); + 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 */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(read_host_config(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; } -cp - return 0; -} -int send_add_host(conn_list_t *cl, conn_list_t *new_host) -{ - ip_t real_ip; - int flags; - char *hostname; -cp - real_ip = new_host->real_ip; - hostname = new_host->real_hostname; - flags = new_host->flags; - - /* If we need to propagate information about a new host that wants us to export - * it's indirectdata flag, we set the INDIRECTDATA flag and unset the EXPORT... - * flag, and set it's real_ip to our vpn_ip, so that net.c send_packet() will - * work correctly. + /* 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(flags & EXPORTINDIRECTDATA) + + if(cl->status.outgoing) { - flags &= ~EXPORTINDIRECTDATA; - flags |= INDIRECTDATA; - real_ip = myself->vpn_ip; - hostname = myself->real_hostname; + 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; + } } + + /* Now we can add the name to the id tree */ + + id_add(cl); - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending ADD_HOST for %s (%s) to %s (%s)"), - new_host->vpn_hostname, hostname, cl->vpn_hostname, cl->real_hostname); + /* And uhr... cl->port just changed so we have to unlink it from the connection tree and re-insert... */ + + avl_unlink(connection_tree, cl); + cl->port = port; + avl_insert(connection_tree, cl); - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx/%lx:%x %d\n", ADD_HOST, real_ip, new_host->vpn_ip, new_host->vpn_mask, new_host->port, flags); + /* Read in the public key, so that we can send a challenge */ + + if(read_rsa_public_key(cl)) + return -1; - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } cp - return 0; + return send_challenge(cl); } -int send_key_changed(conn_list_t *cl, conn_list_t *src) +int send_challenge(connection_t *cl) { + char *buffer; + int len, x; cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending KEY_CHANGED origin %s to %s (%s)"), - src->vpn_hostname, cl->vpn_hostname, cl->real_hostname); + len = RSA_size(cl->rsa_key); - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx\n", KEY_CHANGED, src->vpn_ip); + /* Allocate buffers for the challenge */ - if((write(cl->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } -cp - return 0; -} + buffer = xmalloc(len*2+1); -void send_key_changed_all(void) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - if(p->status.meta && p->status.active) - send_key_changed(p, myself); + if(cl->hischallenge) + free(cl->hischallenge); + + cl->hischallenge = xmalloc(len); cp -} + /* Copy random data to the buffer */ -int send_basic_info(conn_list_t *cl) -{ + RAND_bytes(cl->hischallenge, len); + + cl->hischallenge[0] &= 0x7F; /* Somehow if the first byte is more than 0xD0 or something like that, decryption fails... */ cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending BASIC_INFO to %s"), - cl->real_hostname); + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(cl->hischallenge, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Generated random challenge (unencrypted): %s"), buffer); + } - buflen = snprintf(buffer, MAXBUFSIZE, "%d %d %lx/%lx:%x %d\n", BASIC_INFO, PROT_CURRENT, myself->vpn_ip, myself->vpn_mask, myself->port, myself->flags); + /* Encrypt the random data */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + 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, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); + syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname); + free(buffer); return -1; } cp - return 0; + /* Convert the encrypted random data to a hexadecimal formatted string */ + + bin2hex(buffer, 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 send_passphrase(conn_list_t *cl) +int challenge_h(connection_t *cl) { - passphrase_t tmp; + char buffer[MAX_STRING_SIZE]; + int len; cp - encrypt_passphrase(&tmp); + if(sscanf(cl->buffer, "%*d "MAX_STRING, buffer) != 1) + { + syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, cl->hostname); + return -1; + } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending PASSPHRASE to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + len = RSA_size(myself->rsa_key); - buflen = snprintf(buffer, MAXBUFSIZE, "%d %s\n", PASSPHRASE, tmp.phrase); + /* Check if the length of the challenge is all right */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(strlen(buffer) != len*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); return -1; } -cp - return 0; -} -int send_public_key(conn_list_t *cl) -{ -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending PUBLIC_KEY to %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + /* Allocate buffers for the challenge */ + + if(!cl->mychallenge) + cl->mychallenge = xmalloc(len); - buflen = snprintf(buffer, MAXBUFSIZE, "%d %s\n", PUBLIC_KEY, my_public_key_base36); + /* Convert the challenge from hexadecimal back to binary */ - if((write(cl->meta_socket, buffer, buflen)) < 0) + hex2bin(buffer,buffer,len); + + /* Decrypt the challenge */ + + if(RSA_private_decrypt(len, buffer, cl->mychallenge, myself->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */ { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); + syslog(LOG_ERR, _("Error during encryption of challenge for %s (%s)"), cl->name, cl->hostname); return -1; } -cp - return 0; -} - -/* WDN doet deze functie? (GS) -int send_calculate(conn_list_t *cl, char *k) -{ -cp - buflen = snprintf(buffer, MAXBUFSIZE, "%d %s\n", CALCULATE, k); - if((write(cl->meta_socket, buffer, buflen)) < 0) + if(debug_lvl >= DEBUG_SCARY_THINGS) { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; + bin2hex(cl->mychallenge, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Received random challenge (unencrypted): %s"), buffer); } + + /* Rest is done by send_chal_reply() */ cp - return 0; + return send_chal_reply(cl); } -*/ -int send_key_request(ip_t to) +int send_chal_reply(connection_t *cl) { - conn_list_t *fw; + char hash[SHA_DIGEST_LENGTH*2+1]; cp - fw = lookup_conn(to); - if(!fw) + if(!cl->mychallenge) { - syslog(LOG_ERR, _("Attempting to send REQ_KEY to %d.%d.%d.%d, which does not exist?"), - IP_ADDR_V(to)); + 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 */ - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending REQ_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); + SHA1(cl->mychallenge, RSA_size(myself->rsa_key), hash); - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx\n", REQ_KEY, to, myself->vpn_ip); + /* 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 = METAKEY; - if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0) - { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; - } - fw->status.waitingforkey = 1; cp - return 0; + return send_request(cl, "%d %s", CHAL_REPLY, hash); } -int send_key_answer(conn_list_t *cl, ip_t to) +int chal_reply_h(connection_t *cl) { - conn_list_t *fw; + char hishash[MAX_STRING_SIZE]; + char myhash[SHA_DIGEST_LENGTH]; cp + if(sscanf(cl->buffer, "%*d "MAX_STRING, hishash) != 1) + { + syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname); + return -1; + } - fw = lookup_conn(to); - - if(!fw) + /* Check if the length of the hash is all right */ + + if(strlen(hishash) != SHA_DIGEST_LENGTH*2) { - syslog(LOG_ERR, _("Attempting to send ANS_KEY to %d.%d.%d.%d, which does not exist?"), - IP_ADDR_V(to)); + syslog(LOG_ERR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->name, cl->hostname); return -1; } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Sending ANS_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); + /* Convert the hash to binary format */ - buflen = snprintf(buffer, MAXBUFSIZE, "%d %lx %lx %d %s\n", ANS_KEY, to, myself->vpn_ip, my_key_expiry, my_public_key_base36); + hex2bin(hishash, hishash, SHA_DIGEST_LENGTH); - if((write(fw->nexthop->meta_socket, buffer, buflen)) < 0) + /* Calculate the hash from the challenge we sent */ + + SHA1(cl->hischallenge, RSA_size(cl->rsa_key), myhash); + + /* 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); + if(debug_lvl >= DEBUG_SCARY_THINGS) + { + bin2hex(myhash, hishash, SHA_DIGEST_LENGTH); + hishash[SHA_DIGEST_LENGTH*2] = '\0'; + syslog(LOG_DEBUG, _("Expected challenge reply: %s"), hishash); + } return -1; } -cp - return 0; -} -/* - notify all my direct connections of a new host - that was added to the vpn, with the exception - of the source of the announcement. -*/ -int notify_others(conn_list_t *new, conn_list_t *source, - int (*function)(conn_list_t*, conn_list_t*)) -{ - conn_list_t *p; -cp - for(p = conn_list; p != NULL; p = p->next) - if(p != new && p != source && p->status.meta && p->status.active) - function(p, new); + + /* 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) + return send_metakey(cl); + else + return send_id(cl); } -/* - notify one connection of everything - i have connected -*/ -int notify_one(conn_list_t *new) +int send_metakey(connection_t *cl) { - conn_list_t *p; + char *buffer; + int len, x; cp - for(p = conn_list; p != NULL; p = p->next) - if(p != new && p->status.active) - send_add_host(new, p); -cp - return 0; -} + len = RSA_size(cl->rsa_key); -/* - The incoming request handlers -*/ + /* Allocate buffers for the meta key */ -int basic_info_h(conn_list_t *cl) -{ - conn_list_t *old; -cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got BASIC_INFO from %s"), cl->real_hostname); + buffer = xmalloc(len*2+1); - if(sscanf(cl->buffer, "%*d %d %lx/%lx:%hx %d", &cl->protocol_version, &cl->vpn_ip, &cl->vpn_mask, &cl->port, &cl->flags) != 5) - { - syslog(LOG_ERR, _("Got bad BASIC_INFO from %s"), - cl->real_hostname); - return -1; - } + if(!cl->cipher_outkey) + cl->cipher_outkey = xmalloc(len); - cl->vpn_hostname = hostlookup(htonl(cl->vpn_ip)); + if(!cl->cipher_outctx) + cl->cipher_outctx = xmalloc(sizeof(*cl->cipher_outctx)); +cp + /* Copy random data to the buffer */ - if(cl->protocol_version != PROT_CURRENT) - { - syslog(LOG_ERR, _("Peer uses incompatible protocol version %d"), - cl->protocol_version); - return -1; - } + RAND_bytes(cl->cipher_outkey, len); - if(cl->status.outgoing) - { - /* 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(old=lookup_conn(cl->vpn_ip)) - { - if(debug_lvl>0) - syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), - cl->vpn_hostname, cl->real_hostname); - cl->status.outgoing = 0; - old->status.outgoing = 1; - terminate_connection(cl); - return 0; - } + cl->cipher_outkey[0] &= 0x7F; /* FIXME: Somehow if the first byte is more than 0xD0 or something like that, decryption fails... */ - if(setup_vpn_connection(cl) < 0) - return -1; - send_basic_info(cl); - } - else + if(debug_lvl >= DEBUG_SCARY_THINGS) { - - if(setup_vpn_connection(cl) < 0) - return -1; - send_passphrase(cl); + bin2hex(cl->cipher_outkey, buffer, len); + buffer[len*2] = '\0'; + syslog(LOG_DEBUG, _("Generated random meta key (unencrypted): %s"), buffer); } -cp - return 0; -} - -int passphrase_h(conn_list_t *cl) -{ -cp - cl->pp = xmalloc(sizeof(*(cl->pp))); - if(sscanf(cl->buffer, "%*d %as", &(cl->pp->phrase)) != 1) + /* 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 */ { - syslog(LOG_ERR, _("Got bad PASSPHRASE from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), cl->name, cl->hostname); + free(buffer); return -1; } - cl->pp->len = strlen(cl->pp->phrase); - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got PASSPHRASE from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); +cp + /* Convert the encrypted random data to a hexadecimal formatted string */ + + bin2hex(buffer, buffer, len); + buffer[len*2] = '\0'; + + /* Send the meta key */ if(cl->status.outgoing) - send_passphrase(cl); + cl->allow_request = METAKEY; else - send_public_key(cl); + 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); cp - return 0; + return x; } -int public_key_h(conn_list_t *cl) +int metakey_h(connection_t *cl) { - char *g_n; - conn_list_t *old; + char buffer[MAX_STRING_SIZE]; + int len; cp - if(sscanf(cl->buffer, "%*d %as", &g_n) != 1) + if(sscanf(cl->buffer, "%*d "MAX_STRING, buffer) != 1) { - syslog(LOG_ERR, _("Got bad PUBLIC_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad METAKEY from %s (%s)"), cl->name, cl->hostname); return -1; - } + } + + len = RSA_size(myself->rsa_key); - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got PUBLIC_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + /* Check if the length of the meta key is all right */ - if(verify_passphrase(cl, g_n)) + if(strlen(buffer) != len*2) { - /* intruder! */ - syslog(LOG_ERR, _("Intruder from %s: passphrase for %s does not match!"), - cl->real_hostname, cl->vpn_hostname); + syslog(LOG_ERR, _("Intruder: wrong meta key length from %s (%s)"), cl->name, cl->hostname); return -1; } - if(cl->status.outgoing) - send_public_key(cl); - else - { - send_ack(cl); + /* Allocate buffers for the meta key */ - /* 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. - */ + if(!cl->cipher_inkey) + cl->cipher_inkey = xmalloc(len); - while(old = lookup_conn(cl->vpn_ip)) - { - if(debug_lvl > 1) - syslog(LOG_NOTICE, _("Removing old entry for %s at %s in favour of new connection from %s"), - cl->vpn_hostname, old->real_hostname, cl->real_hostname); - old->status.active = 0; - terminate_connection(old); - } - - cl->status.active = 1; + if(!cl->cipher_inctx) + cl->cipher_inctx = xmalloc(sizeof(*cl->cipher_inctx)); + + /* Convert the challenge from hexadecimal back to binary */ - if(debug_lvl > 0) - syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), - cl->vpn_hostname, cl->real_hostname); + hex2bin(buffer,buffer,len); - notify_others(cl, NULL, send_add_host); - notify_one(cl); + /* Decrypt the meta key */ + + 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); + } + + EVP_DecryptInit(cl->cipher_inctx, EVP_bf_cfb(), cl->cipher_inkey, cl->cipher_inkey + EVP_bf_cfb()->key_len); + cp - return 0; + if(cl->status.outgoing) + return send_ack(cl); + else + return send_metakey(cl); } -int ack_h(conn_list_t *cl) +int send_ack(connection_t *cl) { + int x; cp - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got ACK from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - cl->status.active = 1; - - if(debug_lvl > 0) - syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), - cl->vpn_hostname, cl->real_hostname); - - notify_others(cl, NULL, send_add_host); - notify_one(cl); + if(cl->status.outgoing) + cl->allow_request = ACK; - upstreamindex = 0; + x = send_request(cl, "%d", ACK); + cl->status.encryptout = 1; cp - return 0; + return x; } -int termreq_h(conn_list_t *cl) +int ack_h(connection_t *cl) { + connection_t *old, *p; + subnet_t *subnet; + avl_node_t *node, *node2; cp - if(!cl->status.active) + /* 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))) { - syslog(LOG_ERR, _("Got unauthorized TERMREQ from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - 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); + + terminate_connection(old); } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got TERMREQ from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - - cl->status.termreq = 1; - terminate_connection(cl); -cp - return 0; -} + /* 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); -int timeout_h(conn_list_t *cl) -{ cp - if(!cl->status.active) + if(!cl->status.outgoing) + send_ack(cl); + + /* Send him our subnets */ + + for(node = myself->subnet_tree->head; node; node = node->next) { - syslog(LOG_ERR, _("Got unauthorized TIMEOUT from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; + 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(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got TIMEOUT from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + if(p->status.meta) + send_add_host(p, cl); - cl->status.termreq = 1; - terminate_connection(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 0; } -int del_host_h(conn_list_t *cl) +/* Address and subnet information exchange */ + +int send_add_subnet(connection_t *cl, subnet_t *subnet) +{ + int x; + char *netstr; +cp + x = send_request(cl, "%d %s %s", ADD_SUBNET, + subnet->owner->name, netstr = net2str(subnet)); + free(netstr); +cp + return x; +} + +int add_subnet_h(connection_t *cl) { - ip_t vpn_ip; - conn_list_t *fw; + char subnetstr[MAX_STRING_SIZE]; + char name[MAX_STRING_SIZE]; + connection_t *owner, *p; + subnet_t *subnet; + avl_node_t *node; cp - if(!cl->status.active) + if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, name, subnetstr) != 2) { - syslog(LOG_ERR, _("Got unauthorized DEL_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s)"), cl->name, cl->hostname); return -1; } - if(sscanf(cl->buffer, "%*d %lx", &vpn_ip) != 1) + /* Check if owner name is a valid */ + + if(check_id(name)) { - syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname); + return -1; + } - if(!(fw = lookup_conn(vpn_ip))) + /* Check if subnet string is valid */ + + if(!(subnet = str2net(subnetstr))) { - syslog(LOG_ERR, _("Got DEL_HOST for %d.%d.%d.%d from %s (%s) which does not exist?"), - IP_ADDR_V(vpn_ip), cl->vpn_hostname, cl->real_hostname); - return 0; + syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname); + return -1; } - /* Connections lists are really messed up if this happens */ - if(vpn_ip == myself->vpn_ip) + /* Check if somebody tries to add a subnet of ourself */ + + if(!strcmp(name, myself->name)) { - syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Warning: got ADD_SUBNET from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); sighup = 1; return 0; } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got DEL_HOST for %s (%s) from %s (%s)"), - fw->vpn_hostname, fw->real_hostname, cl->vpn_hostname, cl->real_hostname); + /* Check if the owner of the new subnet is in the connection list */ + + if(!(owner = lookup_id(name))) + { + syslog(LOG_ERR, _("Got ADD_SUBNET for %s from %s (%s) which is not in our connection list"), + name, cl->name, cl->hostname); + return -1; + } - notify_others(fw, cl, send_del_host); + /* If everything is correct, add the subnet to the list of the owner */ - fw->status.termreq = 1; - fw->status.active = 0; + subnet_add(owner, subnet); - terminate_connection(fw); + /* Tell the rest */ + + 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 ping_h(conn_list_t *cl) +int send_del_subnet(connection_t *cl, subnet_t *subnet) { + int x; + char *netstr; cp - if(!cl->status.active) + netstr = net2str(subnet); + x = send_request(cl, "%d %s %s", DEL_SUBNET, subnet->owner->name, netstr); + free(netstr); +cp + return x; +} + +int del_subnet_h(connection_t *cl) +{ + 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 "MAX_STRING" "MAX_STRING, name, subnetstr) != 3) { - syslog(LOG_ERR, _("Got unauthorized PING from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s)"), cl->name, cl->hostname); return -1; } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got PING from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + /* Check if owner name is a valid */ - cl->status.pinged = 0; - cl->status.got_pong = 1; + if(check_id(name)) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid identity name"), cl->name, cl->hostname); + return -1; + } - send_pong(cl); -cp - return 0; -} + /* Check if subnet string is valid */ -int pong_h(conn_list_t *cl) -{ -cp - if(!cl->status.active) + if(!(subnet = str2net(subnetstr))) + { + syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid subnet string"), cl->name, cl->hostname); + 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); + 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 unauthorized PONG from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got DEL_SUBNET for %s from %s (%s) which is not in our connection list"), + name, cl->name, cl->hostname); return -1; } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got PONG from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + /* If everything is correct, delete the subnet from the list of the owner */ - cl->status.got_pong = 1; + subnet_del(subnet); + + /* Tell the rest */ + + 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; } -int add_host_h(conn_list_t *cl) +/* New and closed connections notification */ + +int send_add_host(connection_t *cl, connection_t *other) { - ip_t real_ip; - ip_t vpn_ip; - ip_t vpn_mask; - unsigned short port; - int flags; - conn_list_t *ncn, *old; cp - if(!cl->status.active) + return send_request(cl, "%d %s %lx:%d %lx", ADD_HOST, + other->name, other->address, other->port, other->options); +} + +int add_host_h(connection_t *cl) +{ + connection_t *old, *new, *p; + char name[MAX_STRING_SIZE]; + avl_node_t *node; +cp + new = new_connection(); + + if(sscanf(cl->buffer, "%*d "MAX_STRING" %lx:%d %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; + } + + /* Check if identity is a valid name */ + + if(check_id(name)) { - syslog(LOG_ERR, _("Got unauthorized ADD_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); + free_connection(new); return -1; } - - if(sscanf(cl->buffer, "%*d %lx %lx/%lx:%hx %d", &real_ip, &vpn_ip, &vpn_mask, &port, &flags) != 5) + + /* Check if somebody tries to add ourself */ + + if(!strcmp(name, myself->name)) { - syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } + syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->name, cl->hostname); + sighup = 1; + free_connection(new); + return 0; + } + + /* Fill in more of the new connection structure */ + + new->hostname = hostlookup(htonl(new->address)); - if(old = lookup_conn(vpn_ip)) + /* Check if the new host already exists in the connnection list */ + + if((old = lookup_id(name))) { - if((real_ip==old->real_ip) && (vpn_mask==old->vpn_mask) && (port==old->port)) + if((new->address == old->address) && (new->port == old->port)) { - if(debug_lvl>1) + if(debug_lvl >= DEBUG_CONNECTIONS) syslog(LOG_NOTICE, _("Got duplicate ADD_HOST for %s (%s) from %s (%s)"), - old->vpn_hostname, old->real_hostname, cl->vpn_hostname, cl->real_hostname); - goto skip_add_host; /* One goto a day keeps the deeply nested if constructions away. */ + old->name, old->hostname, name, new->hostname); + free_connection(new); + return 0; } else { - if(debug_lvl>1) - syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"), - old->vpn_hostname, old->real_hostname); - old->status.active = 0; + if(debug_lvl >= DEBUG_CONNECTIONS) + syslog(LOG_NOTICE, _("Removing old entry for %s (%s) in favour of new connection"), + old->name, old->hostname); + terminate_connection(old); } } - - /* Connections lists are really messed up if this happens */ - if(vpn_ip == myself->vpn_ip) + + /* Hook it up into the connection */ + + new->name = xstrdup(name); + connection_add(new); + id_add(new); + + /* Tell the rest about the new host */ + + for(node = connection_tree->head; node; node = node->next) { - syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), - cl->vpn_hostname, cl->real_hostname); - sighup = 1; - return 0; + p = (connection_t *)node->data; + if(p->status.meta && p->status.active && p!=cl) + send_add_host(p, new); } - - ncn = new_conn_list(); - ncn->real_ip = real_ip; - ncn->real_hostname = hostlookup(htonl(real_ip)); - ncn->vpn_ip = vpn_ip; - ncn->vpn_mask = vpn_mask; - ncn->vpn_hostname = hostlookup(htonl(vpn_ip)); - ncn->port = port; - ncn->flags = flags; - ncn->nexthop = cl; - ncn->next = conn_list; - conn_list = ncn; - ncn->status.active = 1; - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got ADD_HOST for %s (%s) from %s (%s)"), - ncn->vpn_hostname, ncn->real_hostname, cl->vpn_hostname, cl->real_hostname); - -skip_add_host: - - notify_others(ncn, cl, send_add_host); + + /* Fill in rest of connection structure */ + + new->nexthop = cl; + new->status.active = 1; + new->cipher_pkttype = EVP_bf_cfb(); + new->cipher_pktkeylength = cl->cipher_pkttype->key_len + cl->cipher_pkttype->iv_len; cp return 0; } -int req_key_h(conn_list_t *cl) +int send_del_host(connection_t *cl, connection_t *other) +{ +cp + return send_request(cl, "%d %s %lx:%d %lx", DEL_HOST, + other->name, other->address, other->port, other->options); +} + +int del_host_h(connection_t *cl) { - ip_t to; - ip_t from; - conn_list_t *fw; + char name[MAX_STRING_SIZE]; + ip_t address; + port_t port; + long int options; + connection_t *old, *p; + avl_node_t *node; cp - if(!cl->status.active) + if(sscanf(cl->buffer, "%*d "MAX_STRING" %lx:%d %lx", name, &address, &port, &options) != 4) { - syslog(LOG_ERR, _("Got unauthorized REQ_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), + cl->name, cl->hostname); return -1; } - if(sscanf(cl->buffer, "%*d %lx %lx", &to, &from) != 2) + /* Check if identity is a valid name */ + + if(check_id(name)) { - syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } + syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s): invalid identity name"), cl->name, cl->hostname); + return -1; + } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got REQ_KEY origin %d.%d.%d.%d destination %d.%d.%d.%d from %s (%s)"), - IP_ADDR_V(from), IP_ADDR_V(to), cl->vpn_hostname, cl->real_hostname); + /* Check if somebody tries to delete ourself */ - if((to & myself->vpn_mask) == (myself->vpn_ip & myself->vpn_mask)) - { /* hey! they want something from ME! :) */ - send_key_answer(cl, from); + if(!strcmp(name, myself->name)) + { + syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), + cl->name, cl->hostname); + sighup = 1; return 0; } - fw = lookup_conn(to); - - if(!fw) + /* Check if the new host already exists in the connnection list */ + + if(!(old = lookup_id(name))) { - syslog(LOG_ERR, _("Attempting to forward REQ_KEY to %d.%d.%d.%d, which does not exist?"), - IP_ADDR_V(to)); + syslog(LOG_ERR, _("Got DEL_HOST from %s (%s) for %s which is not in our connection list"), + name, cl->name, cl->hostname); return -1; } - - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Forwarding REQ_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); - cl->buffer[cl->reqlen-1] = '\n'; + /* Check if the rest matches */ - if(write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen) < 0) + if(address!=old->address || port!=old->port || options!=old->options || cl!=old->nexthop) { - syslog(LOG_ERR, _("Send failed: %s:%d: %m"), __FILE__, __LINE__); - return -1; + 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.active = 0; + terminate_connection(old); + + /* Tell the rest about the new host */ + + 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; } -void set_keys(conn_list_t *cl, int expiry, char *key) +/* Status and error notification routines */ + +int send_status(connection_t *cl, int statusno, char *statusstring) { - char *ek; cp - if(!cl->public_key) + if(!statusstring) + statusstring = status_text[statusno]; +cp + return send_request(cl, "%d %d %s", STATUS, statusno, statusstring); +} + +int status_h(connection_t *cl) +{ + int statusno; + char statusstring[MAX_STRING_SIZE]; +cp + if(sscanf(cl->buffer, "%*d %d "MAX_STRING, &statusno, statusstring) != 2) { - cl->public_key = xmalloc(sizeof(*cl->key)); - cl->public_key->key = NULL; + syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), + cl->name, cl->hostname); + return -1; } - - 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) + + if(debug_lvl >= DEBUG_STATUS) { - cl->key = xmalloc(sizeof(*cl->key)); - cl->key->key = NULL; + syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"), + cl->name, cl->hostname, status_text[statusno], statusstring); } - if(cl->key->key) - free(cl->key->key); +cp + return 0; +} - cl->key->length = strlen(ek); - cl->key->expiry = expiry; - cl->key->key = xmalloc(cl->key->length + 1); - strcpy(cl->key->key, ek); +int send_error(connection_t *cl, int errno, char *errstring) +{ cp + if(!errstring) + errstring = strerror(errno); + return send_request(cl, "%d %d %s", ERROR, errno, errstring); } -int ans_key_h(conn_list_t *cl) +int error_h(connection_t *cl) { - ip_t to; - ip_t from; - int expiry; - char *key; - conn_list_t *fw, *gk; + int errno; + char errorstring[MAX_STRING_SIZE]; cp - if(!cl->status.active) + if(sscanf(cl->buffer, "%*d %d "MAX_STRING, &errno, errorstring) != 2) { - syslog(LOG_ERR, _("Got unauthorized ANS_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; + syslog(LOG_ERR, _("Got bad ERROR from %s (%s)"), + cl->name, cl->hostname); + return -1; } - if(sscanf(cl->buffer, "%*d %lx %lx %d %as", &to, &from, &expiry, &key) != 4) + if(debug_lvl >= DEBUG_ERROR) { - syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); - return -1; - } + syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"), + cl->name, cl->hostname, strerror(errno), errorstring); + } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got ANS_KEY origin %d.%d.%d.%d destination %d.%d.%d.%d from %s (%s)"), - IP_ADDR_V(from), IP_ADDR_V(to), cl->vpn_hostname, cl->real_hostname); + terminate_connection(cl); +cp + return 0; +} - if(to == myself->vpn_ip) - { /* hey! that key's for ME! :) */ - gk = lookup_conn(from); +int send_termreq(connection_t *cl) +{ +cp + return send_request(cl, "%d", TERMREQ); +} - if(!gk) - { - syslog(LOG_ERR, _("Receiving ANS_KEY origin %d.%d.%d.%d from %s (%s), which does not exist?"), - IP_ADDR_V(from), cl->vpn_hostname, cl->real_hostname); - return -1; - } +int termreq_h(connection_t *cl) +{ +cp + terminate_connection(cl); +cp + return 0; +} - set_keys(gk, expiry, key); - gk->status.validkey = 1; - gk->status.waitingforkey = 0; - flush_queues(gk); - return 0; +/* Keepalive routines - FIXME: needs a closer look */ + +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(connection_t *cl) +{ +cp + return send_pong(cl); +} + +int send_pong(connection_t *cl) +{ +cp + return send_request(cl, "%d", PONG); +} + +int pong_h(connection_t *cl) +{ +cp + cl->status.pinged = 0; +cp + return 0; +} + +/* Key exchange */ + +int send_key_changed(connection_t *from, connection_t *cl) +{ + connection_t *p; + avl_node_t *node; +cp + for(node = connection_tree->head; node; node = node->next) + { + p = (connection_t *)node->data; + if(p != cl && p->status.meta && p->status.active) + send_request(p, "%d %s", KEY_CHANGED, from->name); } +cp + return 0; +} - fw = lookup_conn(to); - - if(!fw) +int key_changed_h(connection_t *cl) +{ + char from_id[MAX_STRING_SIZE]; + connection_t *from; +cp + if(sscanf(cl->buffer, "%*d "MAX_STRING, from_id) != 1) { - syslog(LOG_ERR, _("Attempting to forward ANS_KEY to %d.%d.%d.%d, 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 > 1) - syslog(LOG_DEBUG, _("Forwarding ANS_KEY to %s (%s)"), - fw->nexthop->vpn_hostname, fw->nexthop->real_hostname); - - cl->buffer[cl->reqlen-1] = '\n'; - - if((write(fw->nexthop->meta_socket, cl->buffer, cl->reqlen)) < 0) + 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); return -1; } + + from->status.validkey = 0; + from->status.waitingforkey = 0; + + send_key_changed(from, cl); cp return 0; } -int key_changed_h(conn_list_t *cl) +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(connection_t *cl) { - ip_t from; - conn_list_t *ik; + char from_id[MAX_STRING_SIZE]; + char to_id[MAX_STRING_SIZE]; + connection_t *from, *to; + char pktkey[129]; cp - if(!cl->status.active) + if(sscanf(cl->buffer, "%*d "MAX_STRING" "MAX_STRING, from_id, to_id) != 2) { - syslog(LOG_ERR, _("Got unauthorized KEY_CHANGED from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), + cl->name, cl->hostname); + return -1; + } + + if(!(from = lookup_id(from_id))) + { + 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); return -1; } - if(sscanf(cl->buffer, "%*d %lx", &from) != 1) + /* Check if this key request is for us */ + + if(!strcmp(to_id, myself->name)) + { + bin2hex(myself->cipher_pktkey, pktkey, myself->cipher_pktkeylength); + pktkey[myself->cipher_pktkeylength*2] = '\0'; + send_ans_key(myself, from, pktkey); + } + 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); + return -1; + } + + 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); + } + +cp + return 0; +} + +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(connection_t *cl) +{ + 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 "MAX_STRING" "MAX_STRING" "MAX_STRING, from_id, to_id, pktkey) != 3) { - syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), - cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), + cl->name, cl->hostname); return -1; - } + } - ik = lookup_conn(from); + if(!(from = lookup_id(from_id))) + { + 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); + return -1; + } + + /* Check correctness of packet key */ + + keylength = strlen(pktkey); - if(!ik) + if(keylength != from->cipher_pktkeylength*2) { - syslog(LOG_ERR, _("Got KEY_CHANGED origin %d.%d.%d.%d from %s (%s), which does not exist?"), - IP_ADDR_V(from), cl->vpn_hostname, cl->real_hostname); + syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s) origin %s: invalid key length"), + cl->name, cl->hostname, from->name); return -1; } - if(debug_lvl > 1) - syslog(LOG_DEBUG, _("Got KEY_CHANGED origin %s from %s (%s)"), - ik->vpn_hostname, cl->vpn_hostname, cl->real_hostname); + /* 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 */ - ik->status.validkey = 0; - ik->status.waitingforkey = 0; + if(from->cipher_pktkey) + free(from->cipher_pktkey); - notify_others(ik, cl, send_key_changed); + from->cipher_pktkey = xstrdup(pktkey); + keylength /= 2; + hex2bin(from->cipher_pktkey, from->cipher_pktkey, keylength); + from->cipher_pktkey[keylength] = '\0'; + + from->status.validkey = 1; + from->status.waitingforkey = 0; 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[])(connection_t*) = { + id_h, challenge_h, chal_reply_h, metakey_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", "METAKEY", "ACK", + "STATUS", "ERROR", "TERMREQ", + "PING", "PONG", + "ADD_HOST", "DEL_HOST", + "ADD_SUBNET", "DEL_SUBNET", + "KEY_CHANGED", "REQ_KEY", "ANS_KEY", +}; + +/* Status strings */ + +char (*status_text[]) = { + "Warning", +}; + +/* Error strings */ + +char (*error_text[]) = { + "Error", };