-/*
-
- protocol.c
-
- Author: Pekka Riikonen <priikone@silcnet.org>
-
- Copyright (C) 1997 - 2003 Pekka Riikonen
-
- 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
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
-*/
-/*
- * Server side of the protocols.
- */
-/* $Id$ */
-
-#include "serverincludes.h"
-#include "server_internal.h"
-
-SILC_TASK_CALLBACK(silc_server_protocol_connection_auth);
-SILC_TASK_CALLBACK(silc_server_protocol_key_exchange);
-SILC_TASK_CALLBACK(silc_server_protocol_rekey);
-
-/*
- * Key Exhange protocol functions
- */
-
-static bool
-silc_verify_public_key_internal(SilcServer server, SilcSocketConnection sock,
- SilcSocketType conn_type,
- unsigned char *pk, SilcUInt32 pk_len,
- SilcSKEPKType pk_type)
-{
- char file[256], filename[256], *fingerprint;
- struct stat st;
-
- if (pk_type != SILC_SKE_PK_TYPE_SILC) {
- SILC_LOG_WARNING(("We don't support %s (%s) port %d public key type %d",
- sock->hostname, sock->ip, sock->port, pk_type));
- return FALSE;
- }
-
- /* Accept client keys without verification */
- if (conn_type == SILC_SOCKET_TYPE_CLIENT) {
- SILC_LOG_DEBUG(("Accepting client public key without verification"));
- return TRUE;
- }
-
- /* XXX For now, accept server keys without verification too. We are
- currently always doing mutual authentication so the proof of posession
- of the private key is verified, and if server is authenticated in
- conn auth protocol with public key we MUST have the key already. */
- return TRUE;
- /* Rest is unreachable code! */
-
- memset(filename, 0, sizeof(filename));
- memset(file, 0, sizeof(file));
- snprintf(file, sizeof(file) - 1, "serverkey_%s_%d.pub", sock->hostname,
- sock->port);
- snprintf(filename, sizeof(filename) - 1, SILC_ETCDIR "/serverkeys/%s",
- file);
-
- /* Create serverkeys directory if it doesn't exist. */
- if (stat(SILC_ETCDIR "/serverkeys", &st) < 0) {
- /* If dir doesn't exist */
- if (errno == ENOENT) {
- if (mkdir(SILC_ETCDIR "/serverkeys", 0755) < 0) {
- SILC_LOG_ERROR(("Couldn't create `%s' directory\n",
- SILC_ETCDIR "/serverkeys"));
- return TRUE;
- }
- } else {
- SILC_LOG_ERROR(("%s\n", strerror(errno)));
- return TRUE;
- }
- }
-
- /* Take fingerprint of the public key */
- fingerprint = silc_hash_fingerprint(NULL, pk, pk_len);
- SILC_LOG_DEBUG(("Received server %s (%s) port %d public key (%s)",
- sock->hostname, sock->ip, sock->port, fingerprint));
- silc_free(fingerprint);
-
- /* Check whether this key already exists */
- if (stat(filename, &st) < 0) {
- /* We don't have it, then cache it. */
- SILC_LOG_DEBUG(("New public key from server"));
-
- silc_pkcs_save_public_key_data(filename, pk, pk_len,
- SILC_PKCS_FILE_PEM);
- return TRUE;
- } else {
- /* The key already exists, verify it. */
- SilcPublicKey public_key;
- unsigned char *encpk;
- SilcUInt32 encpk_len;
-
- SILC_LOG_DEBUG(("We have the public key saved locally"));
-
- /* Load the key file */
- if (!silc_pkcs_load_public_key(filename, &public_key,
- SILC_PKCS_FILE_PEM))
- if (!silc_pkcs_load_public_key(filename, &public_key,
- SILC_PKCS_FILE_BIN)) {
- SILC_LOG_WARNING(("Could not load local copy of the %s (%s) port %d "
- "server public key", sock->hostname, sock->ip,
- sock->port));
-
- /* Save the key for future checking */
- unlink(filename);
- silc_pkcs_save_public_key_data(filename, pk, pk_len,
- SILC_PKCS_FILE_PEM);
- return TRUE;
- }
-
- /* Encode the key data */
- encpk = silc_pkcs_public_key_encode(public_key, &encpk_len);
- if (!encpk) {
- SILC_LOG_WARNING(("Local copy of the server %s (%s) port %d public key "
- "is malformed", sock->hostname, sock->ip, sock->port));
-
- /* Save the key for future checking */
- unlink(filename);
- silc_pkcs_save_public_key_data(filename, pk, pk_len, SILC_PKCS_FILE_PEM);
- return TRUE;
- }
-
- if (memcmp(pk, encpk, encpk_len)) {
- SILC_LOG_WARNING(("%s (%s) port %d server public key does not match "
- "with local copy", sock->hostname, sock->ip,
- sock->port));
- SILC_LOG_WARNING(("It is possible that the key has expired or changed"));
- SILC_LOG_WARNING(("It is also possible that some one is performing "
- "man-in-the-middle attack"));
- SILC_LOG_WARNING(("Will not accept the server %s (%s) port %d public "
- "key",
- sock->hostname, sock->ip, sock->port));
- return FALSE;
- }
-
- /* Local copy matched */
- return TRUE;
- }
-}
-
-/* Callback that is called when we have received KE2 payload from
- responder. We try to verify the public key now. */
-
-static void
-silc_server_protocol_ke_verify_key(SilcSKE ske,
- unsigned char *pk_data,
- SilcUInt32 pk_len,
- SilcSKEPKType pk_type,
- void *context,
- SilcSKEVerifyCbCompletion completion,
- void *completion_context)
-{
- SilcProtocol protocol = (SilcProtocol)context;
- SilcServerKEInternalContext *ctx =
- (SilcServerKEInternalContext *)protocol->context;
- SilcServer server = (SilcServer)ctx->server;
-
- SILC_LOG_DEBUG(("Verifying received public key"));
-
- if (silc_verify_public_key_internal(
- server, ctx->sock,
- (ctx->responder == FALSE ?
- SILC_SOCKET_TYPE_ROUTER:
- ctx->sconfig.ref_ptr ? SILC_SOCKET_TYPE_SERVER :
- ctx->rconfig.ref_ptr ? SILC_SOCKET_TYPE_ROUTER :
- SILC_SOCKET_TYPE_CLIENT),
- pk_data, pk_len, pk_type))
- completion(ske, SILC_SKE_STATUS_OK, completion_context);
- else
- completion(ske, SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY,
- completion_context);
-}
-
-/* Packet sending callback. This function is provided as packet sending
- routine to the Key Exchange functions. */
-
-static void silc_server_protocol_ke_send_packet(SilcSKE ske,
- SilcBuffer packet,
- SilcPacketType type,
- void *context)
-{
- SilcProtocol protocol = (SilcProtocol)context;
- SilcServerKEInternalContext *ctx =
- (SilcServerKEInternalContext *)protocol->context;
- SilcServer server = (SilcServer)ctx->server;
-
- /* Send the packet immediately */
- silc_server_packet_send(server, ske->sock,
- type, 0, packet->data, packet->len, TRUE);
-}
-
-/* Sets the negotiated key material into use for particular connection. */
-
-int silc_server_protocol_ke_set_keys(SilcServer server,
- SilcSKE ske,
- SilcSocketConnection sock,
- SilcSKEKeyMaterial *keymat,
- SilcCipher cipher,
- SilcPKCS pkcs,
- SilcHash hash,
- SilcHmac hmac,
- SilcSKEDiffieHellmanGroup group,
- bool is_responder)
-{
- SilcUnknownEntry conn_data;
- SilcIDListData idata;
- const char *cname = silc_cipher_get_name(cipher);
-
- SILC_LOG_DEBUG(("Setting new keys into use"));
-
- conn_data = silc_calloc(1, sizeof(*conn_data));
- idata = (SilcIDListData)conn_data;
-
- /* Allocate cipher to be used in the communication */
- if (!silc_cipher_alloc((char *)cname, &idata->send_key)) {
- silc_free(conn_data);
- SILC_LOG_ERROR(("Cannot allocate algorithm: %s", cname));
- return FALSE;
- }
- if (!silc_cipher_alloc((char *)cname, &idata->receive_key)) {
- silc_free(conn_data);
- SILC_LOG_ERROR(("Cannot allocate algorithm: %s", cname));
- return FALSE;
- }
-
- if (!silc_hmac_alloc((char *)silc_hmac_get_name(hmac), NULL,
- &idata->hmac_send)) {
- silc_cipher_free(idata->send_key);
- silc_cipher_free(idata->receive_key);
- silc_free(conn_data);
- SILC_LOG_ERROR(("Cannot allocate algorithm: %s",
- silc_hmac_get_name(hmac)));
- return FALSE;
- }
-
- if (!silc_hmac_alloc((char *)silc_hmac_get_name(hmac), NULL,
- &idata->hmac_receive)) {
- silc_cipher_free(idata->send_key);
- silc_cipher_free(idata->receive_key);
- silc_hmac_free(idata->hmac_send);
- silc_free(conn_data);
- SILC_LOG_ERROR(("Cannot allocate algorithm: %s",
- silc_hmac_get_name(hmac)));
- return FALSE;
- }
-
- if (is_responder == TRUE) {
- silc_cipher_set_key(idata->send_key, keymat->receive_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->send_key, keymat->receive_iv);
- silc_cipher_set_key(idata->receive_key, keymat->send_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->receive_key, keymat->send_iv);
- silc_hmac_set_key(idata->hmac_send, keymat->receive_hmac_key,
- keymat->hmac_key_len);
- silc_hmac_set_key(idata->hmac_receive, keymat->send_hmac_key,
- keymat->hmac_key_len);
- } else {
- silc_cipher_set_key(idata->send_key, keymat->send_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->send_key, keymat->send_iv);
- silc_cipher_set_key(idata->receive_key, keymat->receive_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->receive_key, keymat->receive_iv);
- silc_hmac_set_key(idata->hmac_send, keymat->send_hmac_key,
- keymat->hmac_key_len);
- silc_hmac_set_key(idata->hmac_receive, keymat->receive_hmac_key,
- keymat->hmac_key_len);
- }
-
- idata->rekey = silc_calloc(1, sizeof(*idata->rekey));
- idata->rekey->send_enc_key = silc_memdup(keymat->send_enc_key,
- keymat->enc_key_len / 8);
- idata->rekey->enc_key_len = keymat->enc_key_len / 8;
-
- if (ske->prop->flags & SILC_SKE_SP_FLAG_PFS)
- idata->rekey->pfs = TRUE;
- idata->rekey->ske_group = silc_ske_group_get_number(group);
-
- /* Save the hash */
- if (!silc_hash_alloc(silc_hash_get_name(hash), &idata->hash)) {
- silc_cipher_free(idata->send_key);
- silc_cipher_free(idata->receive_key);
- silc_hmac_free(idata->hmac_send);
- silc_hmac_free(idata->hmac_receive);
- silc_free(conn_data);
- SILC_LOG_ERROR(("Cannot allocate algorithm: %s",
- silc_hash_get_name(hash)));
- return FALSE;
- }
-
- /* Save the remote host's public key */
- silc_pkcs_public_key_decode(ske->ke1_payload->pk_data,
- ske->ke1_payload->pk_len, &idata->public_key);
- if (ske->prop->flags & SILC_SKE_SP_FLAG_MUTUAL)
- silc_hash_make(server->sha1hash, ske->ke1_payload->pk_data,
- ske->ke1_payload->pk_len, idata->fingerprint);
-
- sock->user_data = (void *)conn_data;
-
- SILC_LOG_INFO(("%s (%s) security properties: %s %s %s %s",
- sock->hostname, sock->ip,
- silc_cipher_get_name(idata->send_key),
- (char *)silc_hmac_get_name(idata->hmac_send),
- silc_hash_get_name(idata->hash),
- ske->prop->flags & SILC_SKE_SP_FLAG_PFS ? "PFS" : ""));
-
- return TRUE;
-}
-
-/* Check remote host version string */
-
-SilcSKEStatus silc_ske_check_version(SilcSKE ske, unsigned char *version,
- SilcUInt32 len, void *context)
-{
- SilcUInt32 l_protocol_version = 0, r_protocol_version = 0;
-
- SILC_LOG_INFO(("%s (%s) is version %s", ske->sock->hostname,
- ske->sock->ip, version));
-
- if (!silc_parse_version_string(version, &r_protocol_version, NULL, NULL,
- NULL, NULL)) {
- SILC_LOG_ERROR(("%s (%s) %s is not allowed/supported version",
- ske->sock->hostname, ske->sock->ip, version));
- return SILC_SKE_STATUS_BAD_VERSION;
- }
-
- if (!silc_parse_version_string(silc_version_string,
- &l_protocol_version, NULL, NULL,
- NULL, NULL)) {
- SILC_LOG_ERROR(("%s (%s) %s is not allowed/supported version",
- ske->sock->hostname, ske->sock->ip, version));
- return SILC_SKE_STATUS_BAD_VERSION;
- }
-
- /* If remote is too new, don't connect */
- if (l_protocol_version < r_protocol_version) {
- SILC_LOG_ERROR(("%s (%s) %s is not allowed/supported version",
- ske->sock->hostname, ske->sock->ip, version));
- return SILC_SKE_STATUS_BAD_VERSION;
- }
-
- ske->sock->version = r_protocol_version;
-
- return SILC_SKE_STATUS_OK;
-}
-
-/* Callback that is called by the SKE to indicate that it is safe to
- continue the execution of the protocol. This is used only if we are
- initiator. Is given as argument to the silc_ske_initiator_finish or
- silc_ske_responder_phase_2 functions. This is called due to the fact
- that the public key verification process is asynchronous and we must
- not continue the protocl until the public key has been verified and
- this callback is called. */
-
-static void silc_server_protocol_ke_continue(SilcSKE ske, void *context)
-{
- SilcProtocol protocol = (SilcProtocol)context;
- SilcServerKEInternalContext *ctx =
- (SilcServerKEInternalContext *)protocol->context;
- SilcServer server = (SilcServer)ctx->server;
-
- if (ske->status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(ske->status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Send Ok to the other end. We will end the protocol as responder
- sends Ok to us when we will take the new keys into use. */
- if (ctx->responder == FALSE) {
- SILC_LOG_DEBUG(("Ending key exchange protocol"));
- silc_ske_end(ctx->ske);
-
- /* End the protocol on the next round */
- protocol->state = SILC_PROTOCOL_STATE_END;
- }
-
- /* Advance protocol state and call the next state if we are responder.
- This happens when this callback was sent to silc_ske_responder_phase_2
- function. */
- if (ctx->responder == TRUE) {
- protocol->state++;
- silc_protocol_execute(protocol, server->schedule, 0, 100000);
- }
-}
-
-/* Performs key exchange protocol. This is used for both initiator
- and responder key exchange. This is performed always when accepting
- new connection to the server. This may be called recursively. */
-
-SILC_TASK_CALLBACK(silc_server_protocol_key_exchange)
-{
- SilcProtocol protocol = (SilcProtocol)context;
- SilcServerKEInternalContext *ctx =
- (SilcServerKEInternalContext *)protocol->context;
- SilcServer server = (SilcServer)ctx->server;
- SilcSKEStatus status = SILC_SKE_STATUS_OK;
-
- if (protocol->state == SILC_PROTOCOL_STATE_UNKNOWN)
- protocol->state = SILC_PROTOCOL_STATE_START;
-
- SILC_LOG_DEBUG(("Current protocol state %d", protocol->state));
-
- switch(protocol->state) {
- case SILC_PROTOCOL_STATE_START:
- {
- /*
- * Start protocol
- */
- SilcSKE ske;
-
- /* Allocate Key Exchange object */
- ctx->ske = ske = silc_ske_alloc(server->rng, server);
-
- silc_ske_set_callbacks(ske, silc_server_protocol_ke_send_packet, NULL,
- silc_server_protocol_ke_verify_key,
- silc_server_protocol_ke_continue,
- silc_ske_check_version, context);
-
- if (ctx->responder == TRUE) {
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Start the key exchange by processing the received security
- properties packet from initiator. */
- SILC_LOG_DEBUG(("Process security property list (KE)"));
- status = silc_ske_responder_start(ske, ctx->rng, ctx->sock,
- silc_version_string,
- ctx->packet->buffer, ctx->flags);
- } else {
- SilcSKEStartPayload *start_payload;
-
- SILC_LOG_DEBUG(("Send security property list (KE)"));
-
- /* Assemble security properties. */
- silc_ske_assemble_security_properties(ske, ctx->flags,
- silc_version_string,
- &start_payload);
-
- /* Start the key exchange by sending our security properties
- to the remote end. */
- status = silc_ske_initiator_start(ske, ctx->rng, ctx->sock,
- start_payload);
- }
-
- /* Return now if the procedure is pending. */
- if (status == SILC_SKE_STATUS_PENDING)
- return;
-
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Advance protocol state and call the next state if we are responder */
- protocol->state++;
- if (ctx->responder == TRUE)
- silc_protocol_execute(protocol, server->schedule, 0, 100000);
- }
- break;
- case 2:
- {
- /*
- * Phase 1
- */
- if (ctx->responder == TRUE) {
- /* Sends the selected security properties to the initiator. */
- SILC_LOG_DEBUG(("Send security property list reply (KE)"));
- status = silc_ske_responder_phase_1(ctx->ske);
- } else {
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Call Phase-1 function. This processes the Key Exchange Start
- paylaod reply we just got from the responder. The callback
- function will receive the processed payload where we will
- save it. */
- SILC_LOG_DEBUG(("Process security property list reply (KE)"));
- status = silc_ske_initiator_phase_1(ctx->ske, ctx->packet->buffer);
- }
-
- /* Return now if the procedure is pending. */
- if (status == SILC_SKE_STATUS_PENDING)
- return;
-
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Advance protocol state and call next state if we are initiator */
- protocol->state++;
- if (ctx->responder == FALSE)
- silc_protocol_execute(protocol, server->schedule, 0, 100000);
- }
- break;
- case 3:
- {
- /*
- * Phase 2
- */
- if (ctx->responder == TRUE) {
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Process the received Key Exchange 1 Payload packet from
- the initiator. This also creates our parts of the Diffie
- Hellman algorithm. The silc_server_protocol_ke_continue
- will be called after the public key has been verified. */
- SILC_LOG_DEBUG(("Process KE1 packet"));
- status = silc_ske_responder_phase_2(ctx->ske, ctx->packet->buffer);
- } else {
- /* Call the Phase-2 function. This creates Diffie Hellman
- key exchange parameters and sends our public part inside
- Key Exhange 1 Payload to the responder. */
- SILC_LOG_DEBUG(("Send KE1 packet"));
- status = silc_ske_initiator_phase_2(ctx->ske,
- server->public_key,
- server->private_key,
- SILC_SKE_PK_TYPE_SILC);
- protocol->state++;
- }
-
- /* Return now if the procedure is pending. */
- if (status == SILC_SKE_STATUS_PENDING)
- return;
-
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- }
- break;
- case 4:
- {
- /*
- * Finish protocol
- */
- if (ctx->responder == TRUE) {
- /* This creates the key exchange material and sends our
- public parts to the initiator inside Key Exchange 2 Payload. */
- SILC_LOG_DEBUG(("Process KE2 packet"));
- status = silc_ske_responder_finish(ctx->ske,
- server->public_key,
- server->private_key,
- SILC_SKE_PK_TYPE_SILC);
-
- /* End the protocol on the next round */
- protocol->state = SILC_PROTOCOL_STATE_END;
- } else {
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Finish the protocol. This verifies the Key Exchange 2 payload
- sent by responder. The silc_server_protocol_ke_continue will
- be called after the public key has been verified. */
- SILC_LOG_DEBUG(("Send KE2 packet"));
- status = silc_ske_initiator_finish(ctx->ske, ctx->packet->buffer);
- }
-
- /* Return now if the procedure is pending. */
- if (status == SILC_SKE_STATUS_PENDING)
- return;
-
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Key Exchange protocol with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- }
- break;
-
- case SILC_PROTOCOL_STATE_END:
- {
- /*
- * End protocol
- */
- SilcSKEKeyMaterial *keymat;
- int key_len = silc_cipher_get_key_len(ctx->ske->prop->cipher);
- int hash_len = silc_hash_len(ctx->ske->prop->hash);
-
- SILC_LOG_DEBUG(("Process computed key material"));
-
- /* Process the key material */
- keymat = silc_calloc(1, sizeof(*keymat));
- status = silc_ske_process_key_material(ctx->ske, 16, key_len, hash_len,
- keymat);
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error during Key Exchange protocol: "
- "could not process key material"));
-
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- silc_ske_free_key_material(keymat);
- return;
- }
- ctx->keymat = keymat;
-
- /* Send Ok to the other end if we are responder. If we are initiator
- we have sent this already. */
- if (ctx->responder == TRUE) {
- SILC_LOG_DEBUG(("Ending key exchange protocol"));
- silc_ske_end(ctx->ske);
- }
-
- /* Unregister the timeout task since the protocol has ended.
- This was the timeout task to be executed if the protocol is
- not completed fast enough. */
- if (ctx->timeout_task)
- silc_schedule_task_del(server->schedule, ctx->timeout_task);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* Call the final callback */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- }
- break;
-
- case SILC_PROTOCOL_STATE_ERROR:
- /*
- * Error occured
- */
-
- /* Send abort notification */
- silc_ske_abort(ctx->ske, ctx->ske->status);
-
- /* Unregister the timeout task since the protocol has ended.
- This was the timeout task to be executed if the protocol is
- not completed fast enough. */
- if (ctx->timeout_task)
- silc_schedule_task_del(server->schedule, ctx->timeout_task);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* On error the final callback is always called. */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- break;
-
- case SILC_PROTOCOL_STATE_FAILURE:
- /*
- * We have received failure from remote
- */
-
- /* Unregister the timeout task since the protocol has ended.
- This was the timeout task to be executed if the protocol is
- not completed fast enough. */
- if (ctx->timeout_task)
- silc_schedule_task_del(server->schedule, ctx->timeout_task);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* On error the final callback is always called. */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- break;
-
- case SILC_PROTOCOL_STATE_UNKNOWN:
- break;
- }
-}
-
-/*
- * Connection Authentication protocol functions
- */
-
-static int
-silc_server_password_authentication(SilcServer server, char *local_auth,
- char *remote_auth)
-{
- if (!remote_auth || !local_auth || strlen(local_auth) != strlen(remote_auth))
- return FALSE;
-
- if (!memcmp(remote_auth, local_auth, strlen(local_auth)))
- return TRUE;
-
- return FALSE;
-}
-
-static int
-silc_server_public_key_authentication(SilcServer server,
- SilcPublicKey pub_key,
- unsigned char *sign,
- SilcUInt32 sign_len,
- SilcSKE ske)
-{
- SilcPKCS pkcs;
- int len;
- SilcBuffer auth;
-
- if (!pub_key || !sign)
- return FALSE;
-
- silc_pkcs_alloc(pub_key->name, &pkcs);
- if (!silc_pkcs_public_key_set(pkcs, pub_key)) {
- silc_pkcs_free(pkcs);
- return FALSE;
- }
-
- /* Make the authentication data. Protocol says it is HASH plus
- KE Start Payload. */
- len = ske->hash_len + ske->start_payload_copy->len;
- auth = silc_buffer_alloc(len);
- silc_buffer_pull_tail(auth, len);
- silc_buffer_format(auth,
- SILC_STR_UI_XNSTRING(ske->hash, ske->hash_len),
- SILC_STR_UI_XNSTRING(ske->start_payload_copy->data,
- ske->start_payload_copy->len),
- SILC_STR_END);
-
- /* Verify signature */
- if (silc_pkcs_verify_with_hash(pkcs, ske->prop->hash, sign, sign_len,
- auth->data, auth->len)) {
- silc_pkcs_free(pkcs);
- silc_buffer_free(auth);
- return TRUE;
- }
-
- silc_pkcs_free(pkcs);
- silc_buffer_free(auth);
- return FALSE;
-}
-
-static int
-silc_server_get_public_key_auth(SilcServer server,
- unsigned char **auth_data,
- SilcUInt32 *auth_data_len,
- SilcSKE ske)
-{
- int len;
- SilcPKCS pkcs;
- SilcBuffer auth;
-
- pkcs = server->pkcs;
-
- /* Make the authentication data. Protocol says it is HASH plus
- KE Start Payload. */
- len = ske->hash_len + ske->start_payload_copy->len;
- auth = silc_buffer_alloc(len);
- silc_buffer_pull_tail(auth, len);
- silc_buffer_format(auth,
- SILC_STR_UI_XNSTRING(ske->hash, ske->hash_len),
- SILC_STR_UI_XNSTRING(ske->start_payload_copy->data,
- ske->start_payload_copy->len),
- SILC_STR_END);
-
- *auth_data = silc_calloc((silc_pkcs_get_key_len(pkcs) / 8) + 1,
- sizeof(**auth_data));
- if (silc_pkcs_sign_with_hash(pkcs, ske->prop->hash, auth->data,
- auth->len, *auth_data, auth_data_len)) {
- silc_buffer_free(auth);
- return TRUE;
- }
-
- SILC_LOG_ERROR(("Error computing signature"));
-
- silc_free(*auth_data);
- silc_buffer_free(auth);
- return FALSE;
-}
-
-/* Function that actually performs the authentication to the remote. This
- supports both passphrase and public key authentication. */
-
-static bool
-silc_server_get_authentication(SilcServerConnAuthInternalContext *ctx,
- char *local_passphrase,
- SilcHashTable local_publickeys,
- unsigned char *remote_auth,
- SilcUInt32 remote_auth_len)
-{
- SilcServer server = (SilcServer)ctx->server;
- SilcSKE ske = ctx->ske;
- bool result = FALSE;
-
- /* If we don't have authentication data set at all we do not require
- authentication at all */
- if (!local_passphrase && (!local_publickeys ||
- !silc_hash_table_count(local_publickeys))) {
- SILC_LOG_DEBUG(("No authentication required"));
- return TRUE;
- }
-
- /* If both passphrase and public key is provided then we'll try both of
- them and see which one of them authenticates. If only one of them is
- set, then try only that. */
-
- /* Try first passphrase (as it is faster to check) */
- if (local_passphrase) {
- SILC_LOG_DEBUG(("Password authentication"));
- result = silc_server_password_authentication(server, local_passphrase,
- remote_auth);
- }
-
- /* Try public key authenetication */
- if (!result && local_publickeys) {
- SilcPublicKey cached_key;
- SilcPublicKey remote_key =
- ((SilcIDListData)ctx->sock->user_data)->public_key;
-
- SILC_LOG_DEBUG(("Public key authentication"));
-
- /* Find the public key to be used in authentication */
- cached_key = silc_server_find_public_key(server, local_publickeys,
- remote_key);
- if (!cached_key)
- return FALSE;
-
- result = silc_server_public_key_authentication(server, cached_key,
- remote_auth,
- remote_auth_len, ske);
- }
-
- SILC_LOG_DEBUG(("Authentication %s", result ? "successful" : "failed"));
-
- return result;
-}
-
-/* Performs connection authentication protocol. If responder, we
- authenticate the remote data received. If initiator, we will send
- authentication data to the remote end. */
-
-SILC_TASK_CALLBACK(silc_server_protocol_connection_auth)
-{
- SilcProtocol protocol = (SilcProtocol)context;
- SilcServerConnAuthInternalContext *ctx =
- (SilcServerConnAuthInternalContext *)protocol->context;
- SilcServer server = (SilcServer)ctx->server;
-
- if (protocol->state == SILC_PROTOCOL_STATE_UNKNOWN)
- protocol->state = SILC_PROTOCOL_STATE_START;
-
- SILC_LOG_DEBUG(("Current protocol state %d", protocol->state));
-
- switch(protocol->state) {
- case SILC_PROTOCOL_STATE_START:
- {
- /*
- * Start protocol.
- */
-
- if (ctx->responder == TRUE) {
- /*
- * We are receiving party
- */
- int ret;
- SilcUInt16 payload_len;
- SilcUInt16 conn_type;
- unsigned char *auth_data = NULL;
-
- SILC_LOG_INFO(("Performing authentication protocol for %s (%s)",
- ctx->sock->hostname, ctx->sock->ip));
-
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Bad authentication protocol request"));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Parse the received authentication data packet. The received
- payload is Connection Auth Payload. */
- ret = silc_buffer_unformat(ctx->packet->buffer,
- SILC_STR_UI_SHORT(&payload_len),
- SILC_STR_UI_SHORT(&conn_type),
- SILC_STR_END);
- if (ret == -1) {
- SILC_LOG_ERROR(("Bad payload in authentication packet"));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- if (payload_len != ctx->packet->buffer->len) {
- SILC_LOG_ERROR(("Bad payload length in authentication packet"));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- payload_len -= 4;
-
- if (conn_type < SILC_SOCKET_TYPE_CLIENT ||
- conn_type > SILC_SOCKET_TYPE_ROUTER) {
- SILC_LOG_ERROR(("Bad connection type (%d) in authentication packet",
- conn_type));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- if (payload_len > 0) {
- /* Get authentication data */
- silc_buffer_pull(ctx->packet->buffer, 4);
- ret = silc_buffer_unformat(ctx->packet->buffer,
- SILC_STR_UI_XNSTRING_ALLOC(&auth_data,
- payload_len),
- SILC_STR_END);
- if (ret == -1) {
- SILC_LOG_DEBUG(("Bad payload in authentication payload"));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- }
-
- /*
- * Check the remote connection type and make sure that we have
- * configured this connection. If we haven't allowed this connection
- * the authentication must be failed.
- */
-
- SILC_LOG_DEBUG(("Remote connection type %d", conn_type));
-
- /* Remote end is client */
- if (conn_type == SILC_SOCKET_TYPE_CLIENT) {
- SilcServerConfigClient *client = ctx->cconfig.ref_ptr;
-
- if (client) {
- ret = silc_server_get_authentication(ctx, client->passphrase,
- client->publickeys,
- auth_data, payload_len);
- if (!ret) {
- /* Authentication failed */
- SILC_LOG_ERROR(("Authentication failed"));
- silc_free(auth_data);
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- } else {
- SILC_LOG_ERROR(("Remote client connection not configured"));
- SILC_LOG_ERROR(("Authentication failed"));
- silc_free(auth_data);
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule,
- 0, 300000);
- return;
- }
- }
-
- /* Remote end is server */
- if (conn_type == SILC_SOCKET_TYPE_SERVER) {
- SilcServerConfigServer *serv = ctx->sconfig.ref_ptr;
-
- if (serv) {
- ret = silc_server_get_authentication(ctx, serv->passphrase,
- serv->publickeys,
- auth_data, payload_len);
- if (!ret) {
- /* Authentication failed */
- SILC_LOG_ERROR(("Authentication failed"));
- silc_free(auth_data);
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- } else {
- SILC_LOG_ERROR(("Remote server connection not configured"));
- SILC_LOG_ERROR(("Authentication failed"));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule,
- 0, 300000);
- silc_free(auth_data);
- return;
- }
- }
-
- /* Remote end is router */
- if (conn_type == SILC_SOCKET_TYPE_ROUTER) {
- SilcServerConfigRouter *serv = ctx->rconfig.ref_ptr;
-
- if (serv) {
- ret = silc_server_get_authentication(ctx, serv->passphrase,
- serv->publickeys,
- auth_data, payload_len);
- if (!ret) {
- /* Authentication failed */
- SILC_LOG_ERROR(("Authentication failed"));
- silc_free(auth_data);
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- } else {
- SILC_LOG_ERROR(("Remote router connection not configured"));
- SILC_LOG_ERROR(("Authentication failed"));
- silc_free(auth_data);
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule,
- 0, 300000);
- return;
- }
- }
-
- silc_free(auth_data);
-
- /* Save connection type. This is later used to create the
- ID for the connection. */
- ctx->conn_type = conn_type;
-
- /* Advance protocol state. */
- protocol->state = SILC_PROTOCOL_STATE_END;
- silc_protocol_execute(protocol, server->schedule, 0, 0);
-
- } else {
- /*
- * We are initiator. We are authenticating ourselves to a
- * remote server. We will send the authentication data to the
- * other end for verify.
- */
- SilcBuffer packet;
- int payload_len = 0;
- unsigned char *auth_data = NULL;
- SilcUInt32 auth_data_len = 0;
-
- switch(ctx->auth_meth) {
- case SILC_AUTH_NONE:
- /* No authentication required */
- break;
-
- case SILC_AUTH_PASSWORD:
- /* Password authentication */
- if (ctx->auth_data && ctx->auth_data_len) {
- auth_data = strdup(ctx->auth_data);
- auth_data_len = ctx->auth_data_len;
- break;
- }
- break;
-
- case SILC_AUTH_PUBLIC_KEY:
- {
- /* Public key authentication */
- silc_server_get_public_key_auth(server, &auth_data, &auth_data_len,
- ctx->ske);
- break;
- }
- }
-
- payload_len = 4 + auth_data_len;
- packet = silc_buffer_alloc(payload_len);
- silc_buffer_pull_tail(packet, SILC_BUFFER_END(packet));
- silc_buffer_format(packet,
- SILC_STR_UI_SHORT(payload_len),
- SILC_STR_UI_SHORT(server->server_type
- == SILC_SERVER ?
- SILC_SOCKET_TYPE_SERVER :
- SILC_SOCKET_TYPE_ROUTER),
- SILC_STR_UI_XNSTRING(auth_data, auth_data_len),
- SILC_STR_END);
-
- /* Send the packet to server */
- silc_server_packet_send(server, ctx->sock,
- SILC_PACKET_CONNECTION_AUTH, 0,
- packet->data, packet->len, TRUE);
-
- if (auth_data) {
- memset(auth_data, 0, auth_data_len);
- silc_free(auth_data);
- }
- silc_buffer_free(packet);
-
- /* Next state is end of protocol */
- protocol->state = SILC_PROTOCOL_STATE_END;
- }
- }
- break;
-
- case SILC_PROTOCOL_STATE_END:
- {
- /*
- * End protocol
- */
- unsigned char ok[4];
-
- SILC_PUT32_MSB(SILC_AUTH_OK, ok);
-
- /* Authentication successful */
- silc_server_packet_send(server, ctx->sock, SILC_PACKET_SUCCESS,
- 0, ok, 4, TRUE);
-
- /* Unregister the timeout task since the protocol has ended.
- This was the timeout task to be executed if the protocol is
- not completed fast enough. */
- if (ctx->timeout_task)
- silc_schedule_task_del(server->schedule, ctx->timeout_task);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* Protocol has ended, call the final callback */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- }
- break;
- case SILC_PROTOCOL_STATE_ERROR:
- {
- /*
- * Error. Send notify to remote.
- */
- unsigned char error[4];
-
- /* Authentication failed */
- SILC_PUT32_MSB(SILC_AUTH_FAILED, error);
- silc_server_packet_send(server, ctx->sock, SILC_PACKET_FAILURE,
- 0, error, 4, TRUE);
-
- /* Unregister the timeout task since the protocol has ended.
- This was the timeout task to be executed if the protocol is
- not completed fast enough. */
- if (ctx->timeout_task)
- silc_schedule_task_del(server->schedule, ctx->timeout_task);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* On error the final callback is always called. */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- }
- break;
-
- case SILC_PROTOCOL_STATE_FAILURE:
- /*
- * We have received failure from remote
- */
-
- SILC_LOG_ERROR(("Received Authentication Failure"));
-
- /* Unregister the timeout task since the protocol has ended.
- This was the timeout task to be executed if the protocol is
- not completed fast enough. */
- if (ctx->timeout_task)
- silc_schedule_task_del(server->schedule, ctx->timeout_task);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* On error the final callback is always called. */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- break;
-
- case SILC_PROTOCOL_STATE_UNKNOWN:
- break;
- }
-}
-
-/*
- * Re-key protocol routines
- */
-
-/* Actually takes the new keys into use. */
-
-static void
-silc_server_protocol_rekey_validate(SilcServer server,
- SilcServerRekeyInternalContext *ctx,
- SilcIDListData idata,
- SilcSKEKeyMaterial *keymat,
- bool send)
-{
- if (ctx->responder == TRUE) {
- if (send) {
- silc_cipher_set_key(idata->send_key, keymat->receive_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->send_key, keymat->receive_iv);
- silc_hmac_set_key(idata->hmac_send, keymat->receive_hmac_key,
- keymat->hmac_key_len);
- } else {
- silc_cipher_set_key(idata->receive_key, keymat->send_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->receive_key, keymat->send_iv);
- silc_hmac_set_key(idata->hmac_receive, keymat->send_hmac_key,
- keymat->hmac_key_len);
- }
- } else {
- if (send) {
- silc_cipher_set_key(idata->send_key, keymat->send_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->send_key, keymat->send_iv);
- silc_hmac_set_key(idata->hmac_send, keymat->send_hmac_key,
- keymat->hmac_key_len);
- } else {
- silc_cipher_set_key(idata->receive_key, keymat->receive_enc_key,
- keymat->enc_key_len);
- silc_cipher_set_iv(idata->receive_key, keymat->receive_iv);
- silc_hmac_set_key(idata->hmac_receive, keymat->receive_hmac_key,
- keymat->hmac_key_len);
- }
- }
-
- /* Save the current sending encryption key */
- if (!send) {
- memset(idata->rekey->send_enc_key, 0, idata->rekey->enc_key_len);
- silc_free(idata->rekey->send_enc_key);
- idata->rekey->send_enc_key = silc_memdup(keymat->send_enc_key,
- keymat->enc_key_len / 8);
- idata->rekey->enc_key_len = keymat->enc_key_len / 8;
- }
-}
-
-/* This function actually re-generates (when not using PFS) the keys and
- takes them into use. */
-
-void silc_server_protocol_rekey_generate(SilcServer server,
- SilcServerRekeyInternalContext *ctx,
- bool send)
-{
- SilcIDListData idata = (SilcIDListData)ctx->sock->user_data;
- SilcSKEKeyMaterial *keymat;
- SilcUInt32 key_len = silc_cipher_get_key_len(idata->send_key);
- SilcUInt32 hash_len = silc_hash_len(idata->hash);
-
- SILC_LOG_DEBUG(("Generating new %s session keys (no PFS)",
- send ? "sending" : "receiving"));
-
- /* Generate the new key */
- keymat = silc_calloc(1, sizeof(*keymat));
- silc_ske_process_key_material_data(idata->rekey->send_enc_key,
- idata->rekey->enc_key_len,
- 16, key_len, hash_len,
- idata->hash, keymat);
-
- /* Set the keys into use */
- silc_server_protocol_rekey_validate(server, ctx, idata, keymat, send);
-
- silc_ske_free_key_material(keymat);
-}
-
-/* This function actually re-generates (with PFS) the keys and
- takes them into use. */
-
-void
-silc_server_protocol_rekey_generate_pfs(SilcServer server,
- SilcServerRekeyInternalContext *ctx,
- bool send)
-{
- SilcIDListData idata = (SilcIDListData)ctx->sock->user_data;
- SilcSKEKeyMaterial *keymat;
- SilcUInt32 key_len = silc_cipher_get_key_len(idata->send_key);
- SilcUInt32 hash_len = silc_hash_len(idata->hash);
- unsigned char *tmpbuf;
- SilcUInt32 klen;
-
- SILC_LOG_DEBUG(("Generating new %s session keys (with PFS)",
- send ? "sending" : "receiving"));
-
- /* Encode KEY to binary data */
- tmpbuf = silc_mp_mp2bin(ctx->ske->KEY, 0, &klen);
-
- /* Generate the new key */
- keymat = silc_calloc(1, sizeof(*keymat));
- silc_ske_process_key_material_data(tmpbuf, klen, 16, key_len, hash_len,
- idata->hash, keymat);
-
- /* Set the keys into use */
- silc_server_protocol_rekey_validate(server, ctx, idata, keymat, send);
-
- memset(tmpbuf, 0, klen);
- silc_free(tmpbuf);
- silc_ske_free_key_material(keymat);
-}
-
-/* Packet sending callback. This function is provided as packet sending
- routine to the Key Exchange functions. */
-
-static void
-silc_server_protocol_rekey_send_packet(SilcSKE ske,
- SilcBuffer packet,
- SilcPacketType type,
- void *context)
-{
- SilcProtocol protocol = (SilcProtocol)context;
- SilcServerRekeyInternalContext *ctx =
- (SilcServerRekeyInternalContext *)protocol->context;
- SilcServer server = (SilcServer)ctx->server;
-
- /* Send the packet immediately */
- silc_server_packet_send(server, ctx->sock,
- type, 0, packet->data, packet->len, FALSE);
-}
-
-/* Performs re-key as defined in the SILC protocol specification. */
-
-SILC_TASK_CALLBACK(silc_server_protocol_rekey)
-{
- SilcProtocol protocol = (SilcProtocol)context;
- SilcServerRekeyInternalContext *ctx =
- (SilcServerRekeyInternalContext *)protocol->context;
- SilcServer server = (SilcServer)ctx->server;
- SilcIDListData idata = (SilcIDListData)ctx->sock->user_data;
- SilcSKEStatus status;
-
- if (protocol->state == SILC_PROTOCOL_STATE_UNKNOWN)
- protocol->state = SILC_PROTOCOL_STATE_START;
-
- SILC_LOG_DEBUG(("Current protocol state %d", protocol->state));
-
- switch(protocol->state) {
- case SILC_PROTOCOL_STATE_START:
- {
- /*
- * Start protocol.
- */
-
- if (ctx->responder == TRUE) {
- /*
- * We are receiving party
- */
-
- if (ctx->pfs == TRUE) {
- /*
- * Use Perfect Forward Secrecy, ie. negotiate the key material
- * using the SKE protocol.
- */
-
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Error during Re-key, with %s (%s)",
- ctx->sock->hostname, ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- if (ctx->packet->type != SILC_PACKET_KEY_EXCHANGE_1) {
- SILC_LOG_ERROR(("Error during Re-key (R PFS): re-key state is "
- "incorrect (received %d, expected %d packet), "
- "with %s (%s)", ctx->packet->type,
- SILC_PACKET_KEY_EXCHANGE_1, ctx->sock->hostname,
- ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- ctx->ske = silc_ske_alloc(server->rng, server);
- ctx->ske->prop = silc_calloc(1, sizeof(*ctx->ske->prop));
- silc_ske_group_get_by_number(idata->rekey->ske_group,
- &ctx->ske->prop->group);
-
- silc_ske_set_callbacks(ctx->ske,
- silc_server_protocol_rekey_send_packet,
- NULL, NULL, NULL, silc_ske_check_version,
- context);
-
- status = silc_ske_responder_phase_2(ctx->ske, ctx->packet->buffer);
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Re-key (R PFS), with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Advance the protocol state */
- protocol->state++;
- silc_protocol_execute(protocol, server->schedule, 0, 0);
- } else {
- /*
- * Do normal and simple re-key.
- */
-
- /* Send the REKEY_DONE to indicate we will take new keys into use */
- silc_server_packet_queue_purge(server, ctx->sock);
- silc_server_packet_send(server, ctx->sock, SILC_PACKET_REKEY_DONE,
- 0, NULL, 0, FALSE);
-
- /* After we send REKEY_DONE we must set the sending encryption
- key to the new key since all packets after this packet must
- encrypted with the new key. */
- silc_server_protocol_rekey_generate(server, ctx, TRUE);
- silc_server_packet_queue_purge(server, ctx->sock);
-
- /* The protocol ends in next stage. */
- protocol->state = SILC_PROTOCOL_STATE_END;
- }
-
- } else {
- /*
- * We are the initiator of this protocol
- */
-
- /* Start the re-key by sending the REKEY packet */
- silc_server_packet_send(server, ctx->sock, SILC_PACKET_REKEY,
- 0, NULL, 0, FALSE);
-
- if (ctx->pfs == TRUE) {
- /*
- * Use Perfect Forward Secrecy, ie. negotiate the key material
- * using the SKE protocol.
- */
- ctx->ske = silc_ske_alloc(server->rng, server);
- ctx->ske->prop = silc_calloc(1, sizeof(*ctx->ske->prop));
- silc_ske_group_get_by_number(idata->rekey->ske_group,
- &ctx->ske->prop->group);
-
- silc_ske_set_callbacks(ctx->ske,
- silc_server_protocol_rekey_send_packet,
- NULL, NULL, NULL, silc_ske_check_version,
- context);
-
- status = silc_ske_initiator_phase_2(ctx->ske, NULL, NULL, 0);
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Re-key (I PFS), with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* Advance the protocol state */
- protocol->state++;
- } else {
- /*
- * Do normal and simple re-key.
- */
-
- /* Send the REKEY_DONE to indicate we will take new keys into use
- now. */
- silc_server_packet_queue_purge(server, ctx->sock);
- silc_server_packet_send(server, ctx->sock, SILC_PACKET_REKEY_DONE,
- 0, NULL, 0, FALSE);
-
- /* After we send REKEY_DONE we must set the sending encryption
- key to the new key since all packets after this packet must
- encrypted with the new key. */
- silc_server_protocol_rekey_generate(server, ctx, TRUE);
- silc_server_packet_queue_purge(server, ctx->sock);
-
- /* The protocol ends in next stage. */
- protocol->state = SILC_PROTOCOL_STATE_END;
- }
- }
- }
- break;
-
- case 2:
- /*
- * Second state, used only when doing re-key with PFS.
- */
- if (ctx->responder == TRUE) {
- if (ctx->pfs == TRUE) {
- /*
- * Send our KE packet to the initiator now that we've processed
- * the initiator's KE packet.
- */
- status = silc_ske_responder_finish(ctx->ske, NULL, NULL,
- SILC_SKE_PK_TYPE_SILC);
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Re-key (R PFS), with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- }
-
- } else {
- if (ctx->pfs == TRUE) {
- /*
- * The packet type must be KE packet
- */
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Error during Re-key, with %s (%s)",
- ctx->sock->hostname, ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- if (ctx->packet->type != SILC_PACKET_KEY_EXCHANGE_2) {
- SILC_LOG_ERROR(("Error during Re-key (I PFS): re-key state is "
- "incorrect (received %d, expected %d packet), "
- "with %s (%s)", ctx->packet->type,
- SILC_PACKET_KEY_EXCHANGE_2, ctx->sock->hostname,
- ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- status = silc_ske_initiator_finish(ctx->ske, ctx->packet->buffer);
- if (status != SILC_SKE_STATUS_OK) {
- SILC_LOG_ERROR(("Error (%s) during Re-key (I PFS), with %s (%s)",
- silc_ske_map_status(status), ctx->sock->hostname,
- ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
- }
- }
-
- /* Send the REKEY_DONE to indicate we will take new keys into use
- now. */
- silc_server_packet_queue_purge(server, ctx->sock);
- silc_server_packet_send(server, ctx->sock, SILC_PACKET_REKEY_DONE,
- 0, NULL, 0, FALSE);
-
- /* After we send REKEY_DONE we must set the sending encryption
- key to the new key since all packets after this packet must
- encrypted with the new key. */
- silc_server_protocol_rekey_generate_pfs(server, ctx, TRUE);
- silc_server_packet_queue_purge(server, ctx->sock);
-
- /* The protocol ends in next stage. */
- protocol->state = SILC_PROTOCOL_STATE_END;
- break;
-
- case SILC_PROTOCOL_STATE_END:
- /*
- * End protocol
- */
-
- if (!ctx->packet) {
- SILC_LOG_ERROR(("Error during Re-key, with %s (%s)",
- ctx->sock->hostname, ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- if (ctx->packet->type != SILC_PACKET_REKEY_DONE) {
- SILC_LOG_ERROR(("Error during Re-key (%s PFS): re-key state is "
- "incorrect (received %d, expected %d packet), "
- "with %s (%s)", ctx->responder ? "R" : "I",
- ctx->packet->type, SILC_PACKET_REKEY_DONE,
- ctx->sock->hostname, ctx->sock->ip));
- protocol->state = SILC_PROTOCOL_STATE_ERROR;
- silc_protocol_execute(protocol, server->schedule, 0, 300000);
- return;
- }
-
- /* We received the REKEY_DONE packet and all packets after this is
- encrypted with the new key so set the decryption key to the new key */
- if (ctx->pfs == TRUE)
- silc_server_protocol_rekey_generate_pfs(server, ctx, FALSE);
- else
- silc_server_protocol_rekey_generate(server, ctx, FALSE);
- silc_server_packet_queue_purge(server, ctx->sock);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* Protocol has ended, call the final callback */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- break;
-
- case SILC_PROTOCOL_STATE_ERROR:
- /*
- * Error occured
- */
-
- if (ctx->pfs == TRUE)
- /* Send abort notification */
- silc_ske_abort(ctx->ske, ctx->ske->status);
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* On error the final callback is always called. */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- break;
-
- case SILC_PROTOCOL_STATE_FAILURE:
- /*
- * We have received failure from remote
- */
-
- SILC_LOG_ERROR(("Error during Re-Key: received Failure"));
-
- /* Assure that after calling final callback there cannot be pending
- executions for this protocol anymore. This just unregisters any
- timeout callbacks for this protocol. */
- silc_protocol_cancel(protocol, server->schedule);
-
- /* On error the final callback is always called. */
- if (protocol->final_callback)
- silc_protocol_execute_final(protocol, server->schedule);
- else
- silc_protocol_free(protocol);
- break;
-
- case SILC_PROTOCOL_STATE_UNKNOWN:
- break;
- }
-
-}
-
-/* Registers protocols used in server. */
-
-void silc_server_protocols_register(void)
-{
- silc_protocol_register(SILC_PROTOCOL_SERVER_CONNECTION_AUTH,
- silc_server_protocol_connection_auth);
- silc_protocol_register(SILC_PROTOCOL_SERVER_KEY_EXCHANGE,
- silc_server_protocol_key_exchange);
- silc_protocol_register(SILC_PROTOCOL_SERVER_REKEY,
- silc_server_protocol_rekey);
- silc_protocol_register(SILC_PROTOCOL_SERVER_BACKUP,
- silc_server_protocol_backup);
-}
-
-/* Unregisters protocols */
-
-void silc_server_protocols_unregister(void)
-{
- silc_protocol_unregister(SILC_PROTOCOL_SERVER_CONNECTION_AUTH,
- silc_server_protocol_connection_auth);
- silc_protocol_unregister(SILC_PROTOCOL_SERVER_KEY_EXCHANGE,
- silc_server_protocol_key_exchange);
- silc_protocol_unregister(SILC_PROTOCOL_SERVER_REKEY,
- silc_server_protocol_rekey);
- silc_protocol_unregister(SILC_PROTOCOL_SERVER_BACKUP,
- silc_server_protocol_backup);
-}