/*
- protocol.c -- handle the meta-protocol
- Copyright (C) 1999-2001 Ivo Timmermans <itimmermans@bigfoot.com>,
- 2000,2001 Guus Sliepen <guus@sliepen.warande.net>
+ protocol.c -- handle the meta-protocol, basic functions
+ Copyright (C) 1999-2005 Ivo Timmermans,
+ 2000-2013 Guus Sliepen <guus@tinc-vpn.org>
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
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id: protocol.c,v 1.28.4.115 2001/10/31 12:50:24 guus Exp $
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#include "config.h"
-
-#include <sys/types.h>
-
-#include <stdlib.h>
-#include <string.h>
-#include <syslog.h>
-#include <sys/socket.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <stdarg.h>
-#include <errno.h>
+#include "system.h"
-#include <utils.h>
-#include <xalloc.h>
-#include <avl_tree.h>
-#include <list.h>
+#include "conf.h"
+#include "connection.h"
+#include "logger.h"
+#include "meta.h"
+#include "protocol.h"
+#include "utils.h"
+#include "xalloc.h"
-#include <netinet/in.h>
+bool tunnelserver = false;
+bool strictsubnets = false;
-#include <openssl/sha.h>
-#include <openssl/rand.h>
-#include <openssl/evp.h>
+/* Jumptable for the request handlers */
-#ifndef HAVE_RAND_PSEUDO_BYTES
-#define RAND_pseudo_bytes RAND_bytes
-#endif
+static bool (*request_handlers[])(connection_t *) = {
+ id_h, metakey_h, challenge_h, chal_reply_h, ack_h,
+ status_h, error_h, termreq_h,
+ ping_h, pong_h,
+ add_subnet_h, del_subnet_h,
+ add_edge_h, del_edge_h,
+ key_changed_h, req_key_h, ans_key_h, tcppacket_h,
+};
-#include "conf.h"
-#include "net.h"
-#include "netutl.h"
-#include "protocol.h"
-#include "meta.h"
-#include "connection.h"
-#include "node.h"
-#include "edge.h"
-#include "graph.h"
+/* Request names */
-#include "system.h"
+static char (*request_name[]) = {
+ "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY", "ACK",
+ "STATUS", "ERROR", "TERMREQ",
+ "PING", "PONG",
+ "ADD_SUBNET", "DEL_SUBNET",
+ "ADD_EDGE", "DEL_EDGE", "KEY_CHANGED", "REQ_KEY", "ANS_KEY", "PACKET",
+};
-int mykeyused = 0;
+static avl_tree_t *past_request_tree;
-int check_id(char *id)
-{
- int i;
+bool check_id(const char *id) {
+ for(; *id; id++)
+ if(!isalnum(*id) && *id != '_')
+ return false;
- for (i = 0; i < strlen(id); i++)
- if(!isalnum(id[i]) && id[i] != '_')
- return -1;
-
- return 0;
+ return true;
}
/* Generic request routines - takes care of logging and error
detection as well */
-int send_request(connection_t *c, 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 */
-
- va_start(args, format);
- len = vsnprintf(buffer, MAXBUFSIZE, format, args);
- request = va_arg(args, int);
- va_end(args);
+bool send_request(connection_t *c, const char *format, ...) {
+ va_list args;
+ char buffer[MAXBUFSIZE];
+ int len, request = 0;
- if(len < 0 || len > MAXBUFSIZE-1)
- {
- syslog(LOG_ERR, _("Output buffer overflow while sending %s to %s (%s)"), request_name[request], c->name, c->hostname);
- return -1;
- }
+ /* Use vsnprintf instead of vxasprintf: faster, no memory
+ fragmentation, cleanup is automatic, and there is a limit on the
+ input buffer anyway */
- if(debug_lvl >= DEBUG_PROTOCOL)
- {
- if(debug_lvl >= DEBUG_META)
- syslog(LOG_DEBUG, _("Sending %s to %s (%s): %s"), request_name[request], c->name, c->hostname, buffer);
- else
- syslog(LOG_DEBUG, _("Sending %s to %s (%s)"), request_name[request], c->name, c->hostname);
- }
+ va_start(args, format);
+ len = vsnprintf(buffer, MAXBUFSIZE, format, args);
+ va_end(args);
- buffer[len++] = '\n';
-cp
- return send_meta(c, buffer, len);
-}
-
-int receive_request(connection_t *c)
-{
- int request;
-cp
- if(sscanf(c->buffer, "%d", &request) == 1)
- {
- if((request < 0) || (request >= LAST) || (request_handlers[request] == NULL))
- {
- if(debug_lvl >= DEBUG_META)
- syslog(LOG_DEBUG, _("Unknown request from %s (%s): %s"),
- c->name, c->hostname, c->buffer);
- else
- syslog(LOG_ERR, _("Unknown request from %s (%s)"),
- c->name, c->hostname);
-
- return -1;
- }
- else
- {
- if(debug_lvl >= DEBUG_PROTOCOL)
- {
- if(debug_lvl >= DEBUG_META)
- syslog(LOG_DEBUG, _("Got %s from %s (%s): %s"),
- request_name[request], c->name, c->hostname, c->buffer);
- else
- syslog(LOG_DEBUG, _("Got %s from %s (%s)"),
- request_name[request], c->name, c->hostname);
- }
+ if(len < 0 || len > MAXBUFSIZE - 1) {
+ logger(LOG_ERR, "Output buffer overflow while sending request to %s (%s)",
+ c->name, c->hostname);
+ return false;
}
- 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];
-int bla;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" %d", name, &c->protocol_version) != 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ID", c->name, c->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ID", c->name, c->hostname, "invalid name");
- 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(bypass_security)
- {
- if(!c->config_tree)
- init_configuration(&c->config_tree);
- c->allow_request = ACK;
- return send_ack(c);
- }
-
- if(!c->config_tree)
- {
- init_configuration(&c->config_tree);
-
- if((bla = 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 %s from %s (%s)"), "METAKEY", 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, _("Possible intruder %s (%s): %s"), c->name, c->hostname, "wrong keylength");
- 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 %s from %s (%s)"), "CHALLENGE", 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, _("Possible intruder %s (%s): %s"), c->name, c->hostname, "wrong challenge length");
- 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
- /* 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 %s from %s (%s)"), "CHAL_REPLY", 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, _("Possible intruder %s (%s): %s"), c->name, c->hostname, _("wrong challenge reply length"));
- 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, _("Possible intruder %s (%s): %s"), c->name, c->hostname, _("wrong challenge reply"));
- 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 edge_t structures. */
-
- struct timeval now;
-
- /* Estimate weight */
-
- gettimeofday(&now, NULL);
- c->estimated_weight = (now.tv_sec - c->start.tv_sec) * 1000 + (now.tv_usec - c->start.tv_usec) / 1000;
-cp
- return send_request(c, "%d %hd %d", ACK, myself->port, c->estimated_weight);
-}
-
-int ack_h(connection_t *c)
-{
- port_t port;
- int weight;
- node_t *n;
- subnet_t *s;
- edge_t *e;
- connection_t *other;
- avl_node_t *node, *node2;
-cp
- if(sscanf(c->buffer, "%*d %hd %d", &port, &weight) != 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ACK", c->name, 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->address = c->address;
- 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 an edge_t for this connection */
-
- c->edge = new_edge();
-
- c->edge->from = myself;
- c->edge->to = n;
- c->edge->weight = (weight + c->estimated_weight) / 2;
- c->edge->connection = c;
-
- edge_add(c->edge);
-
- /* Activate this connection */
-
- c->allow_request = ALL;
- c->status.active = 1;
- c->node->cipher = EVP_bf_cbc();
- c->node->keylength = c->node->cipher->key_len + c->node->cipher->iv_len;
-
- 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 || n == myself)
- continue;
-
- 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);
- }
- }
-
- /* Send all known edges */
-
- for(node = edge_tree->head; node; node = node->next)
- {
- e = (edge_t *)node->data;
-
- if(e == c->edge)
- continue;
-
- send_add_edge(c, e);
- }
-
- /* Notify others of this connection */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
-
- if(other == c)
- continue;
-
- send_add_node(other, c->node);
- send_add_edge(other, c->edge);
- }
-
- /* Run MST and SSSP algorithms */
-
- mst_kruskal();
- sssp_bfs(0);
-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 %s from %s (%s)"), "ADD_SUBNET", c->name, c->hostname);
- return -1;
- }
-
- /* Check if owner name is a valid */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ADD_SUBNET", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- /* Check if subnet string is valid */
-
- if(!(s = str2net(subnetstr)))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ADD_SUBNET", c->name, c->hostname, _("invalid subnet string"));
- 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 from %s (%s) for %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 %s from %s (%s)"), "DEL_SUBNET", c->name, c->hostname);
- return -1;
- }
-
- /* Check if owner name is a valid */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_SUBNET", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- /* Check if subnet string is valid */
-
- if(!(s = str2net(subnetstr)))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_SUBNET", c->name, c->hostname, _("invalid subnet string"));
- return -1;
- }
-
- /* Check if the owner of the new subnet is in the connection list */
-
- if(!(owner = lookup_node(name)))
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) for %s which is not in our connection list"),
- "DEL_SUBNET", c->name, c->hostname, name);
- 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 %s from %s (%s) for %s which does not appear in his subnet tree"),
- "DEL_SUBNET", c->name, c->hostname, name);
- 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 %s from %s (%s)"), "ADD_NODE", c->name, c->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ADD_NODE", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- /* Check if node already exists */
-
- n = lookup_node(name);
-
- if(n)
- {
- /* Check if it matches */
-
- if(n->address != address || n->port != port)
- syslog(LOG_DEBUG, _("Got %s from %s (%s) for %s which does not match existing entry"), "ADD_NODE", c->name, c->hostname, n->name);
-
- return 0;
- }
- 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 %s from %s (%s)"), "DEL_NODE",
- c->name, c->hostname);
- return -1;
- }
-
- /* Check if identity is a valid name */
-
- if(check_id(name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_NODE", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- /* Check if somebody tries to delete ourself */
-
- if(!strcmp(name, myself->name))
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) for ourself!"), "DEL_NODE",
- c->name, c->hostname);
- return -1;
- }
-
- /* Check if the deleted host exists */
-
- n = lookup_node(name);
-
- if(!n)
- {
- syslog(LOG_WARNING, _("Got %s from %s (%s) for %s which does not exist"), "DEL_NODE", c->name, c->hostname, n->name);
- return 0;
- }
-
- /* Check if the rest matches */
-
- if(address != n->address || port != n->port)
- {
- syslog(LOG_WARNING, _("Got %s from %s (%s) for %s which does not match existing entry"), "DEL_NODE", c->name, c->hostname, n->name);
- }
-
- /* 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);
-
- mst_kruskal();
- sssp_bfs(0);
-cp
- return 0;
-}
-
-/* Edges */
-
-int send_add_edge(connection_t *c, edge_t *e)
-{
-cp
- return send_request(c, "%d %s %s %lx %d", ADD_NODE,
- e->from->name, e->to->name, e->options, e->weight);
-}
-
-int add_edge_h(connection_t *c)
-{
- connection_t *other;
- edge_t *e;
- node_t *from, *to;
- char from_name[MAX_STRING_SIZE];
- char to_name[MAX_STRING_SIZE];
- long int options;
- int weight;
- avl_node_t *node;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING" %lx %d", from_name, to_name, &options, &weight) != 4)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ADD_EDGE", c->name, c->hostname);
- return -1;
- }
-
- /* Check if names are valid */
-
- if(check_id(from_name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ADD_EDGE", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- if(check_id(to_name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ADD_EDGE", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- /* Lookup nodes */
-
- from = lookup_node(from_name);
-
- if(!from)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ADD_EDGE", c->name, c->hostname, _("unknown node"));
- return -1;
- }
-
- to = lookup_node(to_name);
-
- if(!to)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "ADD_EDGE", c->name, c->hostname, _("unknown node"));
- return -1;
- }
-
- /* Check if edge already exists */
-
- e = lookup_edge(from, to);
-
- if(e)
- {
- if(e->weight != weight || e->options != options)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) which does not match existing entry"), "ADD_EDGE", c->name, c->hostname);
- return -1;
- }
-
- return 0;
- }
- else
- {
- e = new_edge();
- e->from = from;
- e->to = to;
- e->options = options;
- e->weight = weight;
- edge_add(e);
- }
-
- /* Tell the rest about the new edge */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other != c)
- send_add_edge(other, e);
- }
-
- /* Run MST before or after we tell the rest? */
-
- mst_kruskal();
- sssp_bfs(0);
-cp
- return 0;
-}
-
-int send_del_edge(connection_t *c, edge_t *e)
-{
-cp
- return send_request(c, "%d %s %s %lx %d", DEL_EDGE,
- e->from->name, e->to->name, e->options, e->weight);
-}
-
-int del_edge_h(connection_t *c)
-{
- edge_t *e;
- char from_name[MAX_STRING_SIZE];
- char to_name[MAX_STRING_SIZE];
- node_t *from, *to;
- long int options;
- int weight;
- connection_t *other;
- avl_node_t *node;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING" %lx %d", from_name, to_name, &options, &weight) != 4)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "DEL_EDGE",
- c->name, c->hostname);
- return -1;
- }
-
- /* Check if names are valid */
-
- if(check_id(from_name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_EDGE", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- if(check_id(to_name))
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_EDGE", c->name, c->hostname, _("invalid name"));
- return -1;
- }
-
- /* Lookup nodes */
-
- from = lookup_node(from_name);
-
- if(!from)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_EDGE", c->name, c->hostname, _("unknown node"));
- return -1;
- }
-
- to = lookup_node(to_name);
-
- if(!to)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_EDGE", c->name, c->hostname, _("unknown node"));
- return -1;
- }
-
- /* Check if edge exists */
-
- e = lookup_edge(from, to);
-
- if(e)
- {
- if(e->weight != weight || e->options != options)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) which does not match existing entry"), "ADD_EDGE", c->name, c->hostname);
- return -1;
- }
- }
- else
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s): %s"), "DEL_EDGE", c->name, c->hostname, _("unknown edge"));
- return -1;
- }
-
- /* Tell the rest about the deleted edge */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other != c)
- send_del_edge(other, e);
- }
-
- /* Delete the edge */
-
- edge_del(e);
-
- /* Run MST before or after we tell the rest? */
-
- mst_kruskal();
- sssp_bfs(1);
-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 %s from %s (%s)"), "STATUS",
- 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);
- }
+ ifdebug(PROTOCOL) {
+ sscanf(buffer, "%d", &request);
+ ifdebug(META)
+ logger(LOG_DEBUG, "Sending %s to %s (%s): %s",
+ request_name[request], c->name, c->hostname, buffer);
+ else
+ logger(LOG_DEBUG, "Sending %s to %s (%s)", request_name[request],
+ c->name, c->hostname);
+ }
-cp
- return 0;
-}
+ buffer[len++] = '\n';
-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);
+ if(c == everyone) {
+ broadcast_meta(NULL, buffer, len);
+ return true;
+ } else
+ return send_meta(c, buffer, len);
}
-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 %s from %s (%s)"), "ERROR",
- c->name, c->hostname);
- return -1;
- }
+void forward_request(connection_t *from) {
+ int request;
- if(debug_lvl >= DEBUG_ERROR)
- {
- syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"),
- c->name, c->hostname, strerror(err), errorstring);
- }
+ ifdebug(PROTOCOL) {
+ sscanf(from->buffer, "%d", &request);
+ ifdebug(META)
+ logger(LOG_DEBUG, "Forwarding %s from %s (%s): %s",
+ request_name[request], from->name, from->hostname,
+ from->buffer);
+ else
+ logger(LOG_DEBUG, "Forwarding %s from %s (%s)",
+ request_name[request], from->name, from->hostname);
+ }
- terminate_connection(c, c->status.active);
-cp
- return 0;
-}
+ from->buffer[from->reqlen - 1] = '\n';
-int send_termreq(connection_t *c)
-{
-cp
- return send_request(c, "%d", TERMREQ);
+ broadcast_meta(from, from->buffer, from->reqlen);
}
-int termreq_h(connection_t *c)
-{
-cp
- terminate_connection(c, c->status.active);
-cp
- return 0;
-}
+bool receive_request(connection_t *c) {
+ int request;
-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);
-}
-
-int ping_h(connection_t *c)
-{
-cp
- return send_pong(c);
-}
+ if(c->outgoing && proxytype == PROXY_HTTP && c->allow_request == ID) {
+ if(!c->buffer[0] || c->buffer[0] == '\r')
+ return true;
+ if(!strncasecmp(c->buffer, "HTTP/1.1 ", 9)) {
+ if(!strncmp(c->buffer + 9, "200", 3)) {
+ logger(LOG_DEBUG, "Proxy request granted");
+ return true;
+ } else {
+ logger(LOG_DEBUG, "Proxy request rejected: %s", c->buffer + 9);
+ return false;
+ }
+ }
+ }
-int send_pong(connection_t *c)
-{
- char salt[SALTLEN*2+1];
-cp
- RAND_pseudo_bytes(salt, SALTLEN);
- bin2hex(salt, salt, SALTLEN);
- salt[SALTLEN*2] = '\0';
-cp
- return send_request(c, "%d %s", PONG, salt);
-}
+ if(sscanf(c->buffer, "%d", &request) == 1) {
+ if((request < 0) || (request >= LAST) || !request_handlers[request]) {
+ ifdebug(META)
+ logger(LOG_DEBUG, "Unknown request from %s (%s): %s",
+ c->name, c->hostname, c->buffer);
+ else
+ logger(LOG_ERR, "Unknown request from %s (%s)",
+ c->name, c->hostname);
+
+ return false;
+ } else {
+ ifdebug(PROTOCOL) {
+ ifdebug(META)
+ logger(LOG_DEBUG, "Got %s from %s (%s): %s",
+ request_name[request], c->name, c->hostname,
+ c->buffer);
+ else
+ logger(LOG_DEBUG, "Got %s from %s (%s)",
+ request_name[request], c->name, c->hostname);
+ }
+ }
+
+ if((c->allow_request != ALL) && (c->allow_request != request)) {
+ logger(LOG_ERR, "Unauthorized request from %s (%s)", c->name,
+ c->hostname);
+ return false;
+ }
+
+ if(!request_handlers[request](c)) {
+ /* Something went wrong. Probably scriptkiddies. Terminate. */
+
+ logger(LOG_ERR, "Error while processing %s from %s (%s)",
+ request_name[request], c->name, c->hostname);
+ return false;
+ }
+ } else {
+ logger(LOG_ERR, "Bogus data received from %s (%s)",
+ c->name, c->hostname);
+ return false;
+ }
-int pong_h(connection_t *c)
-{
-cp
- c->status.pinged = 0;
-cp
- return 0;
+ return true;
}
-/* Key exchange */
-
-int send_key_changed(connection_t *c, node_t *n)
-{
- connection_t *other;
- avl_node_t *node;
-cp
- /* Only send this message if some other daemon requested our key previously.
- This reduces unnecessary key_changed broadcasts.
- */
-
- if(n == myself && !mykeyused)
- return 0;
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other != c && other->status.active)
- send_request(other, "%d %s", KEY_CHANGED, n->name);
- }
-cp
- return 0;
+static int past_request_compare(const past_request_t *a, const past_request_t *b) {
+ return strcmp(a->request, b->request);
}
-int key_changed_h(connection_t *c)
-{
- char name[MAX_STRING_SIZE];
- node_t *n;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING, name) != 1)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "KEY_CHANGED",
- c->name, c->hostname);
- return -1;
- }
-
- n = lookup_node(name);
-
- if(!n)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) origin %s which does not exist"), "KEY_CHANGED",
- c->name, c->hostname, name);
- return -1;
- }
-
- n->status.validkey = 0;
- n->status.waitingforkey = 0;
-
- send_key_changed(c, n);
-cp
- return 0;
-}
+static void free_past_request(past_request_t *r) {
+ if(r->request)
+ free(r->request);
-int send_req_key(connection_t *c, node_t *from, node_t *to)
-{
-cp
- return send_request(c, "%d %s %s", REQ_KEY,
- from->name, to->name);
+ free(r);
}
-int req_key_h(connection_t *c)
-{
- char from_name[MAX_STRING_SIZE];
- char to_name[MAX_STRING_SIZE];
- node_t *from, *to;
- char key[MAX_STRING_SIZE];
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING, from_name, to_name) != 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "REQ_KEY",
- c->name, c->hostname);
- return -1;
- }
-
- from = lookup_node(from_name);
-
- if(!from)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) origin %s which does not exist in our connection list"), "REQ_KEY",
- c->name, c->hostname, from_name);
- return -1;
- }
-
- to = lookup_node(to_name);
-
- if(!to)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) destination %s which does not exist in our connection list"), "REQ_KEY",
- c->name, c->hostname, to_name);
- return -1;
- }
-
- /* Check if this key request is for us */
-
- if(to == myself) /* Yes, send our own key back */
- {
- bin2hex(myself->key, key, myself->keylength);
- key[myself->keylength * 2] = '\0';
- send_ans_key(c, myself, from, key);
- mykeyused = 1;
- }
- else
- {
- if(to->status.validkey) /* Proxy keys */
- {
- bin2hex(to->key, key, to->keylength);
- key[to->keylength * 2] = '\0';
- send_ans_key(c, to, from, key);
- }
- else
- send_req_key(to->nexthop->connection, from, to);
- }
-
-cp
- return 0;
+void init_requests(void) {
+ past_request_tree = avl_alloc_tree((avl_compare_t) past_request_compare, (avl_action_t) free_past_request);
}
-int send_ans_key(connection_t *c, node_t *from, node_t *to, char *key)
-{
-cp
- return send_request(c, "%d %s %s %s", ANS_KEY,
- from->name, to->name, key);
+void exit_requests(void) {
+ avl_delete_tree(past_request_tree);
}
-int ans_key_h(connection_t *c)
-{
- char from_name[MAX_STRING_SIZE];
- char to_name[MAX_STRING_SIZE];
- char key[MAX_STRING_SIZE];
- int keylength;
- node_t *from, *to;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING, from_name, to_name, key) != 3)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ANS_KEY",
- c->name, c->hostname);
- return -1;
- }
-
- from = lookup_node(from_name);
-
- if(!from)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) origin %s which does not exist in our connection list"), "ANS_KEY",
- c->name, c->hostname, from_name);
- return -1;
- }
-
- to = lookup_node(to_name);
+bool seen_request(char *request) {
+ past_request_t *new, p = {NULL};
- if(!to)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) destination %s which does not exist in our connection list"), "ANS_KEY",
- c->name, c->hostname, to_name);
- return -1;
- }
+ p.request = request;
- /* Check correctness of packet key */
-
- keylength = strlen(key);
-
- if(keylength != from->keylength * 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s) origin %s: %s"), "ANS_KEY",
- c->name, c->hostname, from->name, _("invalid key length"));
- return -1;
- }
-
- /* Forward it if necessary */
-
- if(to != myself)
- {
- send_ans_key(to->nexthop->connection, from, to, key);
- }
-
- /* Update our copy of the origin's packet key */
-
- if(from->key)
- free(from->key);
-
- from->key = xstrdup(key);
- keylength /= 2;
- hex2bin(from->key, from->key, keylength);
- from->key[keylength] = '\0';
-
- from->status.validkey = 1;
- from->status.waitingforkey = 0;
-
- flush_queue(from);
-cp
- return 0;
+ if(avl_search(past_request_tree, &p)) {
+ ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Already seen request");
+ return true;
+ } else {
+ new = xmalloc(sizeof(*new));
+ new->request = xstrdup(request);
+ new->firstseen = now;
+ avl_insert(past_request_tree, new);
+ return false;
+ }
}
-int send_tcppacket(connection_t *c, vpn_packet_t *packet)
-{
- int x;
-cp
- /* Evil hack. */
+void age_past_requests(void) {
+ avl_node_t *node, *next;
+ past_request_t *p;
+ int left = 0, deleted = 0;
- x = send_request(c, "%d %hd", PACKET, packet->len);
+ for(node = past_request_tree->head; node; node = next) {
+ next = node->next;
+ p = node->data;
- if(x)
- return x;
-cp
- return send_meta(c, packet->data, packet->len);
-}
-
-int tcppacket_h(connection_t *c)
-{
- short int len;
-cp
- if(sscanf(c->buffer, "%*d %hd", &len) != 1)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "PACKET", c->name, c->hostname);
- return -1;
- }
-
- /* Set reqlen to len, this will tell receive_meta() that a tcppacket is coming. */
+ if(p->firstseen + pinginterval <= now)
+ avl_delete_node(past_request_tree, node), deleted++;
+ else
+ left++;
+ }
- c->tcplen = len;
-cp
- return 0;
+ if(left || deleted)
+ ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Aging past requests: deleted %d, left %d",
+ deleted, left);
}
-
-/* Jumptable for the request handlers */
-
-int (*request_handlers[])(connection_t*) = {
- id_h, metakey_h, challenge_h, chal_reply_h, ack_h,
- status_h, error_h, termreq_h,
- ping_h, pong_h,
- add_node_h, del_node_h,
- add_subnet_h, del_subnet_h,
- add_edge_h, del_edge_h,
- key_changed_h, req_key_h, ans_key_h,
- tcppacket_h,
-};
-
-/* Request names */
-
-char (*request_name[]) = {
- "ID", "METAKEY", "CHALLENGE", "CHAL_REPLY", "ACK",
- "STATUS", "ERROR", "TERMREQ",
- "PING", "PONG",
- "ADD_NODE", "DEL_NODE",
- "ADD_SUBNET", "DEL_SUBNET",
- "ADD_EDGE", "DEL_EDGE",
- "KEY_CHANGED", "REQ_KEY", "ANS_KEY",
- "PACKET",
-};
-
-/* Status strings */
-
-char (*status_text[]) = {
- "Warning",
-};
-
-/* Error strings */
-
-char (*error_text[]) = {
- "Error",
-};
projects / tinc / blobdiff