-#include "system.h"
-
-/* Generic outgoing request routine - takes care of logging and error detection as well */
-
-int send_request(conn_list_t *cl, const char *format, int request, /*args*/ ...)
-{
- va_list args;
- char *buffer = NULL;
-cp
- if(debug_lvl >= DEBUG_PROTOCOL)
- syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), requestname[request], cl->id, cl->hostname);
-
- va_start(args, format);
- len = vasprintf(&buffer, format, args);
- va_end(args);
-
- if(len < 0 || !buffer)
- {
- syslog(LOG_ERR, _("Error during vasprintf(): %m"));
- return -1;
- }
-
- if(debug_lvl >= DEBUG_META)
- syslog(LOG_DEBUG, _("Sending meta data to %s (%s): %s"), cl->id, cl->hostname, buffer);
-
- if(cl->status.encryptout)
- {
- /* FIXME: Do encryption */
- }
-
- if((write(cl->meta_socket, buffer, buflen)) < 0)
- {
- syslog(LOG_ERR, _("Sending meta data failed: %m"));
- return -1;
- }
-cp
-}
-
-/* Connection protocol:
-
- Client Server
- send_id(*)
- send_challenge
- send_chal_reply(*)
- send_id
- send_challenge
- send_chal_reply
- send_ack
- send_ack
-
- (*) Unencrypted.
-*/
-
-int send_id(conn_list_t *cl)
-{
-cp
- return send_request(cl, "%d %s %d %s", ID, myself->id, myself->version, opt2str(myself->options));
-}
-
-int id_h(conn_list_t *cl)
-{
- conn_list_t *old;
- char *options;
-cp
- if(sscanf(cl->buffer, "%*d %as %d %as", &cl->id, &cl->version, &options) != 3)
- {
- syslog(LOG_ERR, _("Got bad ID from %s"), cl->hostname);
- return -1;
- }
-
- /* Check if version matches */
-
- if(cl->version != myself->version)
- {
- syslog(LOG_ERR, _("Peer %s uses incompatible version %d"), cl->hostname, cl->min_version, cl->max_version);
- return -1;
- }
-
- /* Check if option string is valid */
-
- if((cl->options = str2opt(options)) == -1)
- {
- syslog(LOG_ERR, _("Peer %s uses invalid option string"), cl->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(!check_id(cl->id))
- {
- 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->id);
- 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->id)))
- {
- if(debug_lvl > DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Uplink %s (%s) is already in our connection list"), cl->id, cl->hostname);
- cl->status.outgoing = 0;
- old->status.outgoing = 1;
- terminate_connection(cl);
- return 0;
- }
- }
-
- /* Since we know the identity now, we can encrypt the meta channel */
-
- cl->status.encryptout = 1;
-
- /* 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;
- int keylength;
- int x;
-cp
- if(cl->chal_hash)
- free(cl->chal_hash);
-
- /* Allocate buffers for the challenge and the hash */
-
- cl->chal_hash = xmalloc(SHA_DIGEST_LEN);
- keylength = BN_num_bytes(cl->metakey.n);
- buffer = xmalloc(keylength*2);
-
- /* Copy random data and the public key to the buffer */
-
- RAND_bytes(buffer, keylength);
- BN_bn2bin(cl->metakey.n, buffer+keylength);
-
- /* Calculate the hash from that */
-
- SHA1(buffer, keylength*2, cl->chal_hash);
-
- /* Convert the random data to a hexadecimal formatted string */
-
- bin2hex(buffer,buffer,keylength);
- buffer[keylength*2] = '\0';
-
- /* 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)
-{
- char *challenge;
-cp
- if(sscanf(cl->buffer, "%*d %as", &cl->id, &challenge) != 1)
- {
- syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Rest is done by send_chal_reply() */
-
- x = send_chal_reply(cl, challenge);
- free(challenge);
-cp
- return x;
-}
-
-int send_chal_reply(conn_list_t *cl, char *challenge)
-{
- char *buffer;
- int keylength;
- char *hash;
- int x;
-cp
- keylength = BN_num_bytes(myself->meyakey.n);
-
- /* Check if the length of the challenge is all right */
-
- if(strlen(challenge) != keylength*2)
- {
- syslog(LOG_ERROR, _("Intruder: wrong challenge length from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Allocate buffers for the challenge and the hash */
-
- buffer = xmalloc(keylength*2);
- hash = xmalloc(SHA_DIGEST_LEN*2+1);
-
- /* Copy the incoming random data and our public key to the buffer */
-
- hex2bin(challenge, buffer, keylength);
- BN_bn2bin(myself->metakey.n, buffer+keylength);
-
- /* Calculate the hash from that */
-
- SHA1(buffer, keylength*2, hash);
- free(buffer);
-
- /* Convert the hash to a hexadecimal formatted string */
-
- bin2hex(hash,hash,SHA_DIGEST_LEN);
- hash[SHA_DIGEST_LEN*2] = '\0';
-
- /* Send the reply */
-
- if(cl->status.outgoing)
- cl->allow_resuest = ID;
- else
- cl->allow_request = ACK;
-
- x = send_request(cl, "%d %s", CHAL_REPLY, hash);
- free(hash);
-cp
- return x;
-}
-
-int chal_reply_h(conn_list_t *cl)
-{
- char *hash;
-cp
- if(sscanf(cl->buffer, "%*d %as", &cl->id, &hash) != 2)
- {
- syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Check if the length of the hash is all right */
-
- if(strlen(hash) != SHA_DIGEST_LEN*2)
- {
- syslog(LOG_ERROR, _("Intruder: wrong challenge reply length from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Convert the hash to binary format */
-
- hex2bin(hash, hash, SHA_DIGEST_LEN);
-
- /* Verify the incoming hash with the calculated hash */
-
- if{!memcmp(hash, cl->chal_hash, SHA_DIGEST_LEN)}
- {
- syslog(LOG_ERROR, _("Intruder: wrong challenge reply from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Identity has now been positively verified.
- If we are accepting this new connection, then send our identity,
- if we are making this connecting, acknowledge.
- */
-
- free(hash);
- free(cl->chal_hash);
-
-cp
- if(cl->status.outgoing)
- {
- cl->allow_request = ACK;
- return send_ack(cl);
- }
- else
- {
- cl->allow_request = CHALLENGE;
- return send_id(cl);
- }
-}
-
-int send_ack(conn_list_t *cl)
-{
-cp
- return send_request(cl, "%d", ACK);
-}
-
-int ack_h(conn_list_t *cl)
-{
- conn_list_t old;
-cp
- /* Okay, before we active the connection, we check if there is another entry
- in the connection list with the same vpn_ip. If so, it presumably is an
- old connection that has timed out but we don't know it yet.
- */
-
- while((old = lookup_id(cl->id)))
- {
- if(debug_lvl > DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Removing old entry for %s at %s in favour of new connection from %s"),
- cl->id, old->hostname, cl->hostname);
- old->status.active = 0;
- terminate_connection(old);
- }
-
- /* Activate this connection */
-
- cl->allow_request = ALL;
- cl->status.active = 1;
-
- if(debug_lvl > DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), cl->id, cl->hostname);
-
- /* Exchange information about other tinc daemons */
-
- notify_others(cl, NULL, send_add_host);
- notify_one(cl);
-
- upstreamindex = 0;
-
-cp
- if(cl->status.outgoing)
- return 0;
- else
- return send_ack(cl);
-}
-
-/* Address and subnet information exchange */
-
-int send_add_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
-{
-cp
- return send_request(cl, "%d %s %d %s", ADD_SUBNET, other->id, subnet->type, net2str(subnet));
-}
-
-int add_subnet_h(conn_list_t *cl)
-{
-}
-
-int send_del_subnet(conn_list_t *cl, conn_list_t *other, subnet_t *subnet)
-{
-cp
- return send_request(cl, "%d %s %d %s", DEL_SUBNET, other->id, subnet->type, net2str(subnet));
-}
-
-int del_subnet_h(conn_list_t *cl)
-{
-}
-
-/* New and closed connections notification */
-
-int send_add_host(conn_list_t *cl, conn_list_t *other)
-{
-cp
- return send_request(cl, "%d %s %lx:%d %s", ADD_HOST, other->id, other->address, other->port, opt2str(other->options));
-}
-
-int add_host_h(conn_list_t *cl)
-{
- char *options;
- conn_list_t *old, *new;
-cp
- new = new_conn_list();
-
- if(sscanf(cl->buffer, "%*d %as %lx:%d %as", &new->id, &new->address, &new->port, &options) != 4)
- {
- syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Check if option string is valid */
-
- if((new->options = str2opt(options) == -1)
- {
- syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid option string"), cl->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(!check_id(new->id))
- {
- syslog(LOG_ERR, _("Got bad ADD_HOST from %s (%s): invalid identity name"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Check if somebody tries to add ourself */
-
- if(!strcmp(new->id, myself->id))
- {
- syslog(LOG_ERR, _("Warning: got ADD_HOST from %s (%s) for ourself, restarting"), cl->id, cl->hostname);
- sighup = 1;
- return 0;
- }
-
- /* Fill in more of the new conn_list structure */
-
- new->hostname = hostlookup(htonl(new->address));
-
- /* Check if the new host already exists in the connnection list */
-
- if((old = lookup_id(id))
- {
- 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->id, old->hostname, new->id, new->hostname);
- return 0;
- }
- else
- {
- if(debug_lvl > DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Removing old entry for %s (%s)"), old->id, old->hostname);
- old->status.active = 0;
- terminate_connection(old);
- }
- }
-
- /* Fill in rest of conn_list structure */
-
- new->nexthop = cl;
- new->status.active = 1;
-
- /* Hook it up into the conn_list */
-
- conn_list_add(conn_list, new);
-
- /* Tell the rest about the new host */
-
- notify_others(new, cl, send_add_host);
-
-cp
- return 0;
-}
-
-int send_del_host(conn_list_t *cl, conn_list_t *other)
-{
-cp
- return send_request(cl, "%d %s %lx:%d", DEL_HOST, other->id, other->address, other->port);
-}
-
-int del_host_h(conn_list_t *cl)
-{
- char *id;
- ip_t address;
- port_t port;
- conn_list_t *old;
-cp
- if(sscanf(cl->buffer, "%*d %as %lx:%d", &id, &address, &port) != 3)
- {
- syslog(LOG_ERR, _("Got bad DEL_HOST from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- /* Check if somebody tries to delete ourself */
-
- if(!strcmp(id, myself->id))
- {
- syslog(LOG_ERR, _("Warning: got DEL_HOST from %s (%s) for ourself, restarting"), cl->id, cl->hostname);
- sighup = 1;
- return 0;
- }
-
- /* Check if the new host already exists in the connnection list */
-
- if((old = lookup_id(id))
- {
- if((address == old->address) && (port == old->port))
- {
- notify_others(old, cl, send_del_host);
-
- fw->status.termreq = 1;
- fw->status.active = 0;
-
- terminate_connection(fw);
-cp
- return 0;
- }
- }
-
- if(debug_lvl > DEBUG_CONNECTIONS)
- {
- syslog(LOG_NOTICE, _("Got DEL_HOST for %s from %s (%s) which is not in our connection list"), id, cl->id, cl->hostname);
- }
-cp
- return 0;
-}
-
-/* Status and error notification routines */
-
-int send_status(conn_list_t *cl, int statusno, char *statusstring)
-{
-cp
- if(!statusstring)
- statusstring = status_text[statusno];
-cp
- return send_request(cl, "%d %d %s", STATUS, statusno, statusstring);
-}
-
-int status_h(conn_list_t *cl)
-{
- int statusno;
- char *statusstring;
-cp
- if(sscanf(cl->buffer, "%*d %d %as", &statusno, &statusstring) != 2)
- {
- syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- if(debug_lvl > DEBUG_STATUS)
- {
- syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"), cl->id, cl->hostname, status_text[statusno], statusstring);
- }
-
-cp
- free(statusstring);
- return 0;
-}
-
-int send_error(conn_list_t *cl, int errno, char *errstring)
-{
-cp
- if(!errorstring)
- errorstring = error_text[errno];
- return send_request(cl, "%d %d %s", ERROR, errno, errstring);
-}
-
-int error_h(conn_list_t *cl)
-{
- int errno;
- char *errorstring;
-cp
- if(sscanf(cl->buffer, "%*d %d %as", &errno, &errorstring) != 2)
- {
- syslog(LOG_ERR, _("Got bad error from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- if(debug_lvl > DEBUG_error)
- {
- syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"), cl->id, cl->hostname, error_text[errno], errorstring);
- }
-
- free(errorstring);
- cl->status.termreq = 1;
- terminate_connection(cl);
-cp
- return 0;
-}
-
-int send_termreq(conn_list_t *cl)
-{
-cp
- return send_request(cl, "%d", TERMREQ);
-}
-
-int termreq_h(conn_list_t *cl)
-{
-cp
- cl->status.termreq = 1;
- terminate_connection(cl);
-cp
- return 0;
-}
-
-/* Keepalive routines - FIXME: needs a closer look */
-
-int send_ping(conn_list_t *cl)
-{
- cl->status.pinged = 1;
-cp
- return send_request(cl, "%d", PING);
-}
-
-int ping_h(conn_list_t *cl)
-{
-cp
- return send_pong(cl);
-}
-
-int send_pong(conn_list_t *cl)
-{
-cp
- return send_request(cl, "%d", PONG);
-}
-
-int pong_h(conn_list_t *cl)
-{
-cp
- cl->status.got_pong = 1;
-cp
- return 0;
-}
-
-/* Key exchange */
-
-int send_key_changed(conn_list_t *from, conn_list_t *cl)
-{
- conn_list_t *p;
-cp
- for(p = conn_list; p != NULL; p = p->next)
- {
- if(p!=cl && p->status.meta && p->status.active)
- send_request(p, "%d %s", KEY_CHANGED, from->id);
- }
-cp
- return 0;
-}
-
-int key_changed_h(conn_list_t *cl)
-{
- char *from_id;
- conn_list_t *from;
-cp
- if(sscanf(cl->buffer, "%*d %as", &from_id) != 1)
- {
- syslog(LOG_ERR, _("Got bad KEY_CHANGED from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- if(!(from = lookup_id(from_id)))
- {
- syslog(LOG_ERR, _("Got KEY_CHANGED from %s (%s) origin %s which does not exist in our connection list"), cl->id, cl->hostname, from_id);
- free(from);
- return -1;
- }
-
- from->status.validkey = 0;
- from->status.waitingforkey = 0;
-
- send_key_changed(from, cl);
-cp
- return 0;
-}
-
-int send_req_key(conn_list_t *from, conn_list_t *to)
-{
-cp
- return send_request(to->nexthop, "%d %s %s", REQ_KEY, from->id, to->id);
-}
-
-int req_key_h(conn_list_t *cl)
-{
- char *from_id, *to_id;
- conn_list_t *from, *to;
-cp
- if(sscanf(cl->buffer, "%*d %as %as", &from_id, &to_id) != 2)
- {
- syslog(LOG_ERR, _("Got bad REQ_KEY from %s (%s)"), cl->id, 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->id, cl->hostname, from_id);
- free(from); free(to);
- return -1;
- }
-
- /* Check if this key request is for us */
-
- if(!strcmp(id, myself->strcmp))
- {
- send_ans_key(myself, from, myself->datakey);
- }
- 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->id, cl->hostname, to_id);
- free(from); free(to);
- return -1;
- }
- send_req_key(from, to);
- }
-
- free(from); free(to);
-cp
- return 0;
-}
-
-int send_ans_key(conn_list_t *from, conn_list_t *to, char *datakey)
-{
-cp
- return send_request(to->nexthop, "%d %s %s %s", ANS_KEY, from->id, to->id, datakey);
-}
-
-int ans_key_h(conn_list_t *cl)
-{
- char *from_id, *to_id, *datakey;
- conn_list_t *from, *to;
-cp
- if(sscanf(cl->buffer, "%*d %as %as %as", &from_id, &to_id, &datakey) != 3)
- {
- syslog(LOG_ERR, _("Got bad ANS_KEY from %s (%s)"), cl->id, cl->hostname);
- return -1;
- }
-
- 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->id, cl->hostname, from_id);
- free(from); free(to); free(datakey);
- return -1;
- }
-
- /* Check if this key request is for us */
-
- if(!strcmp(id, myself->strcmp))
- {
- send_ans_key(myself, from);
- }
- else
- {
- if(!(to = lookup_id(to_id)))
- {
- syslog(LOG_ERR, _("Got ANS_KEY from %s (%s) destination %s which does not exist in our connection list"), cl->id, cl->hostname, to_id);
- free(from); free(to); free(datakey);
- return -1;
- }
- send_ans_key(from, to, datakey);
- }
-
- free(from); free(to); free(datakey);
-cp
- return 0;
-}
-
-