- if((c->allow_request != ALL) && (c->allow_request != request))
- {
- syslog(LOG_ERR, _("Unauthorized request from %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- if(request_handlers[request](c))
- /* Something went wrong. Probably scriptkiddies. Terminate. */
- {
- syslog(LOG_ERR, _("Error while processing %s from %s (%s)"),
- request_name[request], c->name, c->hostname);
- return -1;
- }
- }
- else
- {
- syslog(LOG_ERR, _("Bogus data received from %s (%s)"),
- c->name, c->hostname);
- return -1;
- }
-cp
- return 0;
-}
-
-/* The authentication protocol is described in detail in doc/SECURITY2,
- the rest will be described in doc/PROTOCOL. */
-
-int send_id(connection_t *c)
-{
-cp
- return send_request(c, "%d %s %d", ID, myself->connection->name, myself->connection->protocol_version);
-}
-
-int id_h(connection_t *c)
-{
- char name[MAX_STRING_SIZE];
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" %d", name, &c->protocol_version) != 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s"), "ID", c->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Peer %s uses invalid identity name"), c->hostname);
- return -1;
- }
-
- /* If we set c->name in advance, make sure we are connected to the right host */
-
- if(c->name)
- {
- if(strcmp(c->name, name))
- {
- syslog(LOG_ERR, _("Peer %s is %s instead of %s"), c->hostname, name, c->name);
- return -1;
- }
- }
- else
- c->name = xstrdup(name);
-
- /* Check if version matches */
-
- if(c->protocol_version != myself->connection->protocol_version)
- {
- syslog(LOG_ERR, _("Peer %s (%s) uses incompatible version %d"),
- c->name, c->hostname, c->protocol_version);
- return -1;
- }
-
- if(!c->config_tree)
- {
- if(read_connection_config(c))
- {
- syslog(LOG_ERR, _("Peer %s had unknown identity (%s)"), c->hostname, c->name);
- return -1;
- }
-
- if(read_rsa_public_key(c))
- {
- return -1;
- }
- }
-
- c->allow_request = METAKEY;
-cp
- return send_metakey(c);
-}
-
-int send_metakey(connection_t *c)
-{
- char *buffer;
- int len, x;
-cp
- len = RSA_size(c->rsa_key);
-
- /* Allocate buffers for the meta key */
-
- buffer = xmalloc(len*2+1);
-
- if(!c->outkey)
- c->outkey = xmalloc(len);
-
- if(!c->outctx)
- c->outctx = xmalloc(sizeof(*c->outctx));
-cp
- /* Copy random data to the buffer */
-
- RAND_bytes(c->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.
- */
-
- c->outkey[0] &= 0x7F;
-
- if(debug_lvl >= DEBUG_SCARY_THINGS)
- {
- bin2hex(c->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, c->outkey, buffer, c->rsa_key, RSA_NO_PADDING) != len)
- {
- syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), c->name, c->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(c, "%d %s", METAKEY, buffer);
- free(buffer);
-
- /* Further outgoing requests are encrypted with the key we just generated */
-
- EVP_EncryptInit(c->outctx, EVP_bf_cfb(),
- c->outkey + len - EVP_bf_cfb()->key_len,
- c->outkey + len - EVP_bf_cfb()->key_len - EVP_bf_cfb()->iv_len);
-
- c->status.encryptout = 1;
-cp
- return x;
-}
-
-int metakey_h(connection_t *c)
-{
- char buffer[MAX_STRING_SIZE];
- int len;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING, buffer) != 1)
- {
- syslog(LOG_ERR, _("Got bad METAKEY from %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- len = RSA_size(myself->connection->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)"), c->name, c->hostname);
- return -1;
- }
-
- /* Allocate buffers for the meta key */
-
- if(!c->inkey)
- c->inkey = xmalloc(len);
-
- if(!c->inctx)
- c->inctx = xmalloc(sizeof(*c->inctx));
-
- /* Convert the challenge from hexadecimal back to binary */
-
- hex2bin(buffer,buffer,len);
-
- /* Decrypt the meta key */
-
- if(RSA_private_decrypt(len, buffer, c->inkey, myself->connection->rsa_key, RSA_NO_PADDING) != len) /* See challenge() */
- {
- syslog(LOG_ERR, _("Error during encryption of meta key for %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- if(debug_lvl >= DEBUG_SCARY_THINGS)
- {
- bin2hex(c->inkey, buffer, len);
- buffer[len*2] = '\0';
- syslog(LOG_DEBUG, _("Received random meta key (unencrypted): %s"), buffer);
- }
-
- /* All incoming requests will now be encrypted. */
-
- EVP_DecryptInit(c->inctx, EVP_bf_cfb(),
- c->inkey + len - EVP_bf_cfb()->key_len,
- c->inkey + len - EVP_bf_cfb()->key_len - EVP_bf_cfb()->iv_len);
-
- c->status.decryptin = 1;
-
- c->allow_request = CHALLENGE;
-cp
- return send_challenge(c);
-}
-
-int send_challenge(connection_t *c)
-{
- char *buffer;
- int len, x;
-cp
- /* CHECKME: what is most reasonable value for len? */
-
- len = RSA_size(c->rsa_key);
-
- /* Allocate buffers for the challenge */
-
- buffer = xmalloc(len*2+1);
-
- if(c->hischallenge)
- free(c->hischallenge);
-
- c->hischallenge = xmalloc(len);
-cp
- /* Copy random data to the buffer */
-
- RAND_bytes(c->hischallenge, len);
-
-cp
- /* Convert to hex */
-
- bin2hex(c->hischallenge, buffer, len);
- buffer[len*2] = '\0';
-
-cp
- /* Send the challenge */
-
- x = send_request(c, "%d %s", CHALLENGE, buffer);
- free(buffer);
-cp
- return x;
-}
-
-int challenge_h(connection_t *c)
-{
- char buffer[MAX_STRING_SIZE];
- int len;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING, buffer) != 1)
- {
- syslog(LOG_ERR, _("Got bad CHALLENGE from %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- len = RSA_size(myself->connection->rsa_key);
-
- /* Check if the length of the challenge is all right */
-
- if(strlen(buffer) != len*2)
- {
- syslog(LOG_ERR, _("Intruder: wrong challenge length from %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- /* Allocate buffers for the challenge */
-
- if(!c->mychallenge)
- c->mychallenge = xmalloc(len);
-
- /* Convert the challenge from hexadecimal back to binary */
-
- hex2bin(buffer,c->mychallenge,len);
-
- c->allow_request = CHAL_REPLY;
-
- /* Rest is done by send_chal_reply() */
-cp
- return send_chal_reply(c);
-}
-
-int send_chal_reply(connection_t *c)
-{
- char hash[SHA_DIGEST_LENGTH*2+1];
-cp
- if(!c->mychallenge)
- {
- syslog(LOG_ERR, _("Trying to send CHAL_REPLY to %s (%s) without a valid CHALLENGE"), c->name, c->hostname);
- return -1;
- }
-
- /* Calculate the hash from the challenge we received */
-
- SHA1(c->mychallenge, RSA_size(myself->connection->rsa_key), hash);
-
- /* Convert the hash to a hexadecimal formatted string */
-
- bin2hex(hash,hash,SHA_DIGEST_LENGTH);
- hash[SHA_DIGEST_LENGTH*2] = '\0';
-
- /* Send the reply */
-
-cp
- return send_request(c, "%d %s", CHAL_REPLY, hash);
-}
-
-int chal_reply_h(connection_t *c)
-{
- char hishash[MAX_STRING_SIZE];
- char myhash[SHA_DIGEST_LENGTH];
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING, hishash) != 1)
- {
- syslog(LOG_ERR, _("Got bad CHAL_REPLY from %s (%s)"), c->name, c->hostname);
- 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)"), c->name, c->hostname);
- return -1;
- }
-
- /* Convert the hash to binary format */
-
- hex2bin(hishash, hishash, SHA_DIGEST_LENGTH);
-
- /* Calculate the hash from the challenge we sent */
-
- SHA1(c->hischallenge, RSA_size(c->rsa_key), 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)"), c->name, c->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;
- }
-
- /* Identity has now been positively verified.
- Send an acknowledgement with the rest of the information needed.
- */
-
- c->allow_request = ACK;
-cp
- return send_ack(c);
-}
-
-int send_ack(connection_t *c)
-{
- /* ACK message contains rest of the information the other end needs
- to create node_t and vertex_t structures. */
-cp
- return send_request(c, "%d %d", ACK, myself->port);
-}
-
-int ack_h(connection_t *c)
-{
- port_t port;
- node_t *n;
- subnet_t *s;
- avl_node_t *node, *node2;
-cp
- if(sscanf(c->buffer, "%*d %hd", &port) != 1)
- {
- syslog(LOG_ERR, _("Got bad %s from %s"), "ACK", c->hostname);
- return -1;
- }
-
- /* Check if we already have a node_t for him */
-
- n = lookup_node(c->name);
-
- if(!n)
- {
- n = new_node();
- n->name = xstrdup(c->name);
- n->hostname = xstrdup(c->hostname);
- n->port = port;
-
- /* FIXME: Also check if no other tinc daemon uses the same IP and port for UDP traffic */
-
- node_add(n);
- }
- else
- {
- if(n->connection)
- {
- /* Oh dear, we already have a connection to this node. */
- syslog(LOG_DEBUG, _("Established a second connection with %s (%s), closing old connection"), n->name, n->hostname);
- terminate_connection(n->connection, 0);
- }
-
- /* FIXME: check if information in existing node matches that of the other end of this connection */
- }
-
- n->connection = c;
- c->node = n;
-
- /* Check some options
-
- if((cfg = get_config_val(c->config, config_indirectdata)))
- {
- if(cfg->data.val == stupid_true)
- c->options |= OPTION_INDIRECT;
- }
-
- if((cfg = get_config_val(c->config, config_tcponly)))
- {
- if(cfg->data.val == stupid_true)
- c->options |= OPTION_TCPONLY;
- }
-
- if((myself->options | c->options) & OPTION_INDIRECT)
- c->via = myself;
- else
- c->via = c;
-
- */
-
- /* Create a vertex_t for this connection */
-
- c->vertex = new_vertex();
-
- c->vertex->from = myself;
- c->vertex->to = n;
- c->vertex->metric = 1;
- c->vertex->connection = c;
-
- vertex_add(c->vertex);
-
- /* Activate this connection */
-
- c->allow_request = ALL;
-
- if(debug_lvl >= DEBUG_CONNECTIONS)
- syslog(LOG_NOTICE, _("Connection with %s (%s) activated"), c->name, c->hostname);
-
-cp
- /* Send him our subnets */
-
- for(node = myself->subnet_tree->head; node; node = node->next)
- {
- s = (subnet_t *)node->data;
- send_add_subnet(c, s);
- }
-
- /* And send him all known nodes and their subnets */
-
- for(node = node_tree->head; node; node = node->next)
- {
- n = (node_t *)node->data;
-
- if(n != c->node)
- {
- /* Notify others of this connection */
-
- if(n->connection)
- send_add_node(n->connection, c->node);
-
- /* Notify new connection of everything we know */
-
- send_add_node(c, n);
-
- for(node2 = c->node->subnet_tree->head; node2; node2 = node2->next)
- {
- s = (subnet_t *)node2->data;
- send_add_subnet(c, s);
- }
- }
- }
-cp
- return 0;
-}
-
-
-
-/* Address and subnet information exchange */
-
-int send_add_subnet(connection_t *c, subnet_t *subnet)
-{
- int x;
- char *netstr;
-cp
- x = send_request(c, "%d %s %s", ADD_SUBNET,
- subnet->owner->name, netstr = net2str(subnet));
- free(netstr);
-cp
- return x;
-}
-
-int add_subnet_h(connection_t *c)
-{
- char subnetstr[MAX_STRING_SIZE];
- char name[MAX_STRING_SIZE];
- node_t *owner;
- connection_t *other;
- subnet_t *s;
- avl_node_t *node;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING, name, subnetstr) != 2)
- {
- syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if owner name is a valid */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid identity name"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if subnet string is valid */
-
- if(!(s = str2net(subnetstr)))
- {
- syslog(LOG_ERR, _("Got bad ADD_SUBNET from %s (%s): invalid subnet string"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if the owner of the new subnet is in the connection list */
-
- if(!(owner = lookup_node(name)))
- {
- syslog(LOG_ERR, _("Got ADD_SUBNET for %s from %s (%s) which is not in our connection list"),
- name, c->name, c->hostname);
- return -1;
- }
-
- /* If everything is correct, add the subnet to the list of the owner */
-
- subnet_add(owner, s);
-
- /* Tell the rest */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other != c)
- send_add_subnet(other, s);
- }
-cp
- return 0;
-}
-
-int send_del_subnet(connection_t *c, subnet_t *s)
-{
- int x;
- char *netstr;
-cp
- x = send_request(c, "%d %s %s", DEL_SUBNET, s->owner->name, netstr = net2str(s));
- free(netstr);
-cp
- return x;
-}
-
-int del_subnet_h(connection_t *c)
-{
- char subnetstr[MAX_STRING_SIZE];
- char name[MAX_STRING_SIZE];
- node_t *owner;
- connection_t *other;
- subnet_t *s, *find;
- avl_node_t *node;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING, name, subnetstr) != 3)
- {
- syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if owner name is a valid */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid identity name"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if subnet string is valid */
-
- if(!(s = str2net(subnetstr)))
- {
- syslog(LOG_ERR, _("Got bad DEL_SUBNET from %s (%s): invalid subnet string"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if the owner of the new subnet is in the connection list */
-
- if(!(owner = lookup_node(name)))
- {
- syslog(LOG_ERR, _("Got DEL_SUBNET for %s from %s (%s) which is not in our connection list"),
- name, c->name, c->hostname);
- return -1;
- }
-
- /* If everything is correct, delete the subnet from the list of the owner */
-
- find = lookup_subnet(owner, s);
-
- if(!find)
- {
- syslog(LOG_ERR, _("Got DEL_SUBNET for %s from %s (%s) which does not appear in his subnet tree"),
- name, c->name, c->hostname);
- return -1;
- }
-
- subnet_del(owner, s);
-
- /* Tell the rest */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other != c)
- send_del_subnet(other, s);
- }
-cp
- return 0;
-}
-
-/* New and closed connections notification */
-
-int send_add_node(connection_t *c, node_t *n)
-{
-cp
- return send_request(c, "%d %s %lx:%d", ADD_NODE,
- n->name, n->address, n->port);
-}
-
-int add_node_h(connection_t *c)
-{
- connection_t *other;
- node_t *n;
- char name[MAX_STRING_SIZE];
- ipv4_t address;
- port_t port;
- avl_node_t *node;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" %lx:%hd", name, &address, &port) != 3)
- {
- syslog(LOG_ERR, _("Got bad ADD_NODE from %s (%s)"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad ADD_NODE from %s (%s): invalid identity name"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if somebody tries to add ourself */
-
- if(!strcmp(name, myself->name))
- {
- syslog(LOG_ERR, _("Got ADD_NODE from %s (%s) for ourself!"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if node already exists */
-
- n = lookup_node(name);
-
- if(n)
- {
- /* Check if it matches */
- }
- else
- {
- n = new_node();
- n->name = xstrdup(name);
- n->address = address;
- n->port = port;
- node_add(n);
- }
-
- /* Tell the rest about the new node */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other !=c)
- send_add_node(other, n);
- }
-
-cp
- return 0;
-}
-
-int send_del_node(connection_t *c, node_t *n)
-{
-cp
- return send_request(c, "%d %s %lx:%d", DEL_NODE,
- n->name, n->address, n->port);
-}
-
-int del_node_h(connection_t *c)
-{
- node_t *n;
- char name[MAX_STRING_SIZE];
- ipv4_t address;
- port_t port;
- connection_t *other;
- avl_node_t *node;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" %lx:%hd", name, &address, &port) != 3)
- {
- syslog(LOG_ERR, _("Got bad DEL_NODE from %s (%s)"),
- c->name, c->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad DEL_NODE from %s (%s): invalid identity name"), c->name, c->hostname);
- return -1;
- }
-
- /* Check if somebody tries to delete ourself */
-
- if(!strcmp(name, myself->name))
- {
- syslog(LOG_ERR, _("Got DEL_NODE from %s (%s) for ourself!"),
- c->name, c->hostname);
- return -1;
- }
-
- /* Check if the deleted host exists */
-
- n = lookup_node(name);
-
- if(!n)
- {
- syslog(LOG_WARNING, _("Got DEL_NODE from %s (%s) for %s which does not exist"), c->name, c->hostname, n->name);
- return 0;
- }
-
- /* Check if the rest matches */
-
- if(address != n->address || port != n->port)
- {
- syslog(LOG_WARNING, _("Got DEL_NODE from %s (%s) for %s which doesn't match"), c->name, c->hostname, n->name);
- return 0;
- }
-
- /* Tell the rest about the deleted node */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other != c)
- send_del_node(other, n);
- }
-
- /* Delete the node */
-
- node_del(n);
-cp
- return 0;
-}
-
-/* Status and error notification routines */
-
-int send_status(connection_t *c, int statusno, char *statusstring)
-{
-cp
- if(!statusstring)
- statusstring = status_text[statusno];
-cp
- return send_request(c, "%d %d %s", STATUS, statusno, statusstring);
-}
-
-int status_h(connection_t *c)
-{
- int statusno;
- char statusstring[MAX_STRING_SIZE];
-cp
- if(sscanf(c->buffer, "%*d %d "MAX_STRING, &statusno, statusstring) != 2)
- {
- syslog(LOG_ERR, _("Got bad STATUS from %s (%s)"),
- c->name, c->hostname);
- return -1;
- }
-
- if(debug_lvl >= DEBUG_STATUS)
- {
- syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"),
- c->name, c->hostname, status_text[statusno], statusstring);
- }
-
-cp
- return 0;
-}
-
-int send_error(connection_t *c, int err, char *errstring)
-{
-cp
- if(!errstring)
- errstring = strerror(err);
- return send_request(c, "%d %d %s", ERROR, err, errstring);
-}
-
-int error_h(connection_t *c)
-{
- int err;
- char errorstring[MAX_STRING_SIZE];
-cp
- if(sscanf(c->buffer, "%*d %d "MAX_STRING, &err, errorstring) != 2)
- {
- syslog(LOG_ERR, _("Got bad ERROR from %s (%s)"),
- c->name, c->hostname);
- return -1;
- }
-
- if(debug_lvl >= DEBUG_ERROR)
- {
- syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"),
- c->name, c->hostname, strerror(err), errorstring);
- }
-
- terminate_connection(c, c->status.active);
-cp
- return 0;
-}
-
-int send_termreq(connection_t *c)
-{
-cp
- return send_request(c, "%d", TERMREQ);
-}
-
-int termreq_h(connection_t *c)
-{
-cp
- terminate_connection(c, c->status.active);
-cp
- return 0;
-}
-
-int send_ping(connection_t *c)
-{
- char salt[SALTLEN*2+1];
-cp
- c->status.pinged = 1;
- c->last_ping_time = time(NULL);
- RAND_pseudo_bytes(salt, SALTLEN);
- bin2hex(salt, salt, SALTLEN);
- salt[SALTLEN*2] = '\0';
-cp
- return send_request(c, "%d %s", PING, salt);
-}