- return send_request(cl, "%d %s %d %lx", ID, myself->name, myself->protocol_version, myself->options);
-}
-
-int id_h(conn_list_t *cl)
-{
- conn_list_t *old;
-cp
- if(sscanf(cl->buffer, "%*d %as %d %lx", &cl->name, &cl->protocol_version, &cl->options) != 3)
- {
- syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname);
- return -1;
- }
-
- /* Check if version matches */
-
- if(cl->protocol_version != myself->protocol_version)
- {
- syslog(LOG_ERR, _("Peer %s (%s) uses incompatible version %d"),
- cl->name, cl->hostname, cl->protocol_version);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(!check_id(cl->name))
- {
- syslog(LOG_ERR, _("Peer %s uses invalid identity name"), cl->hostname);
- return -1;
- }
-
- /* Load information about peer */
-
- if(!read_id(cl))
- {
- syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), cl->hostname, cl->name);
- return -1;
- }
-
-
- /* First check if the host we connected to is already in our
- connection list. If so, we are probably making a loop, which
- is not desirable.
- */
-
- if(cl->status.outgoing)
- {
- if((old = lookup_id(cl->name)))
- {
- if(debug_lvl > DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->name, cl->hostname);
- cl->status.outgoing = 0;
- old->status.outgoing = 1;
- terminate_connection(cl);
- return 0;
- }
- }
-
- /* Send a challenge to verify the identity */
-
- cl->allow_request = CHAL_REPLY;
-cp
- return send_challenge(cl);
-}
-
-int send_challenge(conn_list_t *cl)
-{
- char buffer[CHAL_LENGTH*2+1];
-cp
- /* Allocate buffers for the challenge */
-
- if(!cl->hischallenge)
- cl->hischallenge = xmalloc(CHAL_LENGTH);
-
- /* Copy random data to the buffer */
-
- RAND_bytes(cl->hischallenge, CHAL_LENGTH);
-
- /* Convert the random data to a hexadecimal formatted string */
-
- bin2hex(cl->hischallenge,buffer,CHAL_LENGTH);
- buffer[keylength*2] = '\0';
-
- /* Send the challenge */
-
- cl->allow_request = CHAL_REPLY;
-cp
- return send_request(cl, "%d %s", CHALLENGE, buffer);
-}
-
-int challenge_h(conn_list_t *cl)
-{
- char *buffer;
-cp
- if(sscanf(cl->buffer, "%*d %as", &buffer) != 1)
- {
- syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->name, cl->hostname);
- return -1;
- }
-
- /* Check if the length of the challenge is all right */
-
- if(strlen(buffer) != CHAL_LENGTH*2)
- {
- syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), cl->name, cl->hostname);
- free(buffer);
- return -1;
- }
-
- /* Allocate buffers for the challenge */
-
- if(!cl->mychallenge)
- cl->mychallenge = xmalloc(CHAL_LENGTH);
-
- /* Convert the challenge from hexadecimal back to binary */
-
- hex2bin(buffer,cl->mychallenge,CHAL_LENGTH);
- free(buffer);
-
- /* Rest is done by send_chal_reply() */
-cp
- return send_chal_reply(cl);
-}
-
-int send_chal_reply(conn_list_t *cl)
-{
- char hash[SHA_DIGEST_LENGTH*2+1];
-cp
- if(!cl->mychallenge)
- {
- syslog(LOG_ERR, _("Trying to send CHAL_REPLY to %s (%s) without a valid CHALLENGE"), cl->name, cl->hostname);
- return -1;
- }
-
- /* Calculate the hash from the challenge we received */
-
- SHA1(cl->mychallenge, CHAL_LENGTH, hash);
-
- /* Convert the hash to a hexadecimal formatted string */
-
- bin2hex(hash,hash,SHA_DIGEST_LENGTH);
- hash[SHA_DIGEST_LENGTH*2] = '\0';
-
- /* Send the reply */
-
- if(cl->status.outgoing)
- cl->allow_request = ID;
- else
- cl->allow_request = ACK;
-
-cp
- return send_request(cl, "%d %s", CHAL_REPLY, hash);
-}
-
-int chal_reply_h(conn_list_t *cl)
-{
- char *hishash;
- char myhash[SHA_DIGEST_LENGTH];
-cp
- if(sscanf(cl->buffer, "%*d %as", &hishash) != 2)
- {
- syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->name, cl->hostname);
- free(hishash);
- return -1;
- }
-
- /* Check if the length of the hash is all right */
-
- 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;
- }
-
- /* Convert the hash to binary format */
-
- hex2bin(hishash, hishash, SHA_DIGEST_LENGTH);
-
- /* Calculate the hash from the challenge we sent */
-
- SHA1(cl->hischallenge, CHAL_LENGTH, myhash);
-
- /* Verify the incoming hash with the calculated hash */
-
- if(!memcmp(hishash, myhash, SHA_DIGEST_LENGTH))
- {
- syslog(LOG_ERR, _("Intruder: wrong challenge reply from %s (%s)"), cl->name, cl->hostname);
- free(hishash);
- return -1;
- }
-
- free(hishash);
-
- /* Identity has now been positively verified.
- If we are accepting this new connection, then send our identity,
- if we are making this connecting, acknowledge.
- */
-cp
- if(cl->status.outgoing)
- {
- cl->allow_request = ACK;
- return send_ack(cl);
- }