Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
- Copyright (C) 1997 - 2000 Pekka Riikonen
+ 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
*/
/* $Id$ */
-#include "clientlibincludes.h"
+#include "silcincludes.h"
+#include "silcclient.h"
+#include "client_internal.h"
SILC_TASK_CALLBACK(silc_client_protocol_connection_auth);
SILC_TASK_CALLBACK(silc_client_protocol_key_exchange);
-
-extern char *silc_version_string;
+SILC_TASK_CALLBACK(silc_client_protocol_rekey);
/*
* Key Exhange protocol functions
/* Function that is called when SKE protocol sends packets to network. */
-static void silc_client_protocol_ke_send_packet(SilcSKE ske,
- SilcBuffer packet,
- SilcPacketType type,
- void *context)
+void silc_client_protocol_ke_send_packet(SilcSKE ske,
+ SilcBuffer packet,
+ SilcPacketType type,
+ void *context)
{
SilcProtocol protocol = (SilcProtocol)context;
- SilcClientKEInternalContext *ctx =
+ SilcClientKEInternalContext *ctx =
(SilcClientKEInternalContext *)protocol->context;
SilcClient client = (SilcClient)ctx->client;
/* Send the packet immediately */
silc_client_packet_send(client, ske->sock, type, NULL, 0, NULL, NULL,
packet->data, packet->len, TRUE);
+}
+
+/* Public key verification callback. Called by the application. */
+
+typedef struct {
+ SilcSKE ske;
+ SilcSKEVerifyCbCompletion completion;
+ void *completion_context;
+} *VerifyKeyContext;
+
+static void silc_client_verify_key_cb(bool success, void *context)
+{
+ VerifyKeyContext verify = (VerifyKeyContext)context;
+ SILC_LOG_DEBUG(("Start"));
+
+ /* Call the completion callback back to the SKE */
+ verify->completion(verify->ske, success ? SILC_SKE_STATUS_OK :
+ SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY,
+ verify->completion_context);
+
+ silc_free(verify);
}
-/* Callback that is called when we have received KE2 payload from
+/* Callback that is called when we have received KE payload from
responder. We try to verify the public key now. */
-static SilcSKEStatus
-silc_client_protocol_ke_verify_key(SilcSKE ske,
- unsigned char *pk_data,
- unsigned int pk_len,
- SilcSKEPKType pk_type,
- void *context)
+void silc_client_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;
- SilcClientKEInternalContext *ctx =
+ SilcClientKEInternalContext *ctx =
(SilcClientKEInternalContext *)protocol->context;
SilcClient client = (SilcClient)ctx->client;
+ VerifyKeyContext verify;
SILC_LOG_DEBUG(("Start"));
- /* Verify server key from user. */
- if (!client->ops->verify_server_key(client, ctx->sock->user_data,
- pk_data, pk_len, pk_type))
- return SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY;
+ verify = silc_calloc(1, sizeof(*verify));
+ verify->ske = ske;
+ verify->completion = completion;
+ verify->completion_context = completion_context;
- return SILC_SKE_STATUS_OK;
+ /* Verify public key from user. */
+ client->internal->ops->verify_public_key(client, ctx->sock->user_data,
+ ctx->sock->type,
+ pk_data, pk_len, pk_type,
+ silc_client_verify_key_cb, verify);
}
/* Sets the negotiated key material into use for particular connection. */
-static void silc_client_protocol_ke_set_keys(SilcSKE ske,
- SilcSocketConnection sock,
- SilcSKEKeyMaterial *keymat,
- SilcCipher cipher,
- SilcPKCS pkcs,
- SilcHash hash)
+void silc_client_protocol_ke_set_keys(SilcSKE ske,
+ SilcSocketConnection sock,
+ SilcSKEKeyMaterial *keymat,
+ SilcCipher cipher,
+ SilcPKCS pkcs,
+ SilcHash hash,
+ SilcHmac hmac,
+ SilcSKEDiffieHellmanGroup group,
+ bool is_responder)
{
SilcClientConnection conn = (SilcClientConnection)sock->user_data;
- SilcHash nhash;
+ const char *cname = silc_cipher_get_name(cipher);
SILC_LOG_DEBUG(("Setting new keys into use"));
/* Allocate cipher to be used in the communication */
- silc_cipher_alloc(cipher->cipher->name, &conn->send_key);
- silc_cipher_alloc(cipher->cipher->name, &conn->receive_key);
-
- conn->send_key->cipher->set_key(conn->send_key->context,
- keymat->send_enc_key,
- keymat->enc_key_len);
- conn->send_key->set_iv(conn->send_key, keymat->send_iv);
- conn->receive_key->cipher->set_key(conn->receive_key->context,
- keymat->receive_enc_key,
- keymat->enc_key_len);
- conn->receive_key->set_iv(conn->receive_key, keymat->receive_iv);
-
- /* Allocate PKCS to be used */
-#if 0
- /* XXX Do we ever need to allocate PKCS for the connection??
- If yes, we need to change KE protocol to get the initiators
- public key. */
- silc_pkcs_alloc(pkcs->pkcs->name, &conn->public_Key);
- silc_pkcs_set_public_key(conn->public_key, ske->ke2_payload->pk_data,
- ske->ke2_payload->pk_len);
-#endif
-
- /* Save HMAC key to be used in the communication. */
- silc_hash_alloc(hash->hash->name, &nhash);
- silc_hmac_alloc(nhash, &conn->hmac);
- silc_hmac_set_key(conn->hmac, keymat->hmac_key, keymat->hmac_key_len);
+ silc_cipher_alloc((char *)cname, &conn->internal->send_key);
+ silc_cipher_alloc((char *)cname, &conn->internal->receive_key);
+ silc_hmac_alloc((char *)silc_hmac_get_name(hmac), NULL,
+ &conn->internal->hmac_send);
+ silc_hmac_alloc((char *)silc_hmac_get_name(hmac), NULL,
+ &conn->internal->hmac_receive);
+
+ if (is_responder == TRUE) {
+ silc_cipher_set_key(conn->internal->send_key, keymat->receive_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->send_key, keymat->receive_iv);
+ silc_cipher_set_key(conn->internal->receive_key, keymat->send_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->receive_key, keymat->send_iv);
+ silc_hmac_set_key(conn->internal->hmac_send, keymat->receive_hmac_key,
+ keymat->hmac_key_len);
+ silc_hmac_set_key(conn->internal->hmac_receive, keymat->send_hmac_key,
+ keymat->hmac_key_len);
+ } else {
+ silc_cipher_set_key(conn->internal->send_key, keymat->send_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->send_key, keymat->send_iv);
+ silc_cipher_set_key(conn->internal->receive_key, keymat->receive_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->receive_key, keymat->receive_iv);
+ silc_hmac_set_key(conn->internal->hmac_send, keymat->send_hmac_key,
+ keymat->hmac_key_len);
+ silc_hmac_set_key(conn->internal->hmac_receive, keymat->receive_hmac_key,
+ keymat->hmac_key_len);
+ }
+
+ /* Rekey stuff */
+ conn->internal->rekey = silc_calloc(1, sizeof(*conn->internal->rekey));
+ conn->internal->rekey->send_enc_key = silc_memdup(keymat->send_enc_key,
+ keymat->enc_key_len / 8);
+ conn->internal->rekey->enc_key_len = keymat->enc_key_len / 8;
+
+ if (ske->start_payload->flags & SILC_SKE_SP_FLAG_PFS)
+ conn->internal->rekey->pfs = TRUE;
+ conn->internal->rekey->ske_group = silc_ske_group_get_number(group);
+
+ /* Save the HASH function */
+ silc_hash_alloc(silc_hash_get_name(hash), &conn->internal->hash);
}
/* Checks the version string of the server. */
SilcSKEStatus silc_ske_check_version(SilcSKE ske, unsigned char *version,
- unsigned int len)
+ SilcUInt32 len, void *context)
{
- SilcSocketConnection conn = (SilcSocketConnection)ske->sock->user_data;
+ SilcClientConnection conn = (SilcClientConnection)ske->sock->user_data;
SilcClient client = (SilcClient)ske->user_data;
- SilcSKEStatus status = SILC_SKE_STATUS_OK;
+ SilcUInt32 l_protocol_version = 0, r_protocol_version = 0;
+
+ if (!silc_parse_version_string(version, &r_protocol_version, NULL, NULL,
+ NULL, NULL)) {
+ client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_AUDIT,
+ "We don't support server version `%s'",
+ version);
+ return SILC_SKE_STATUS_BAD_VERSION;
+ }
- /* Check for initial version string */
- if (!strstr(version, "SILC-1.0-"))
- status = SILC_SKE_STATUS_BAD_VERSION;
+ if (!silc_parse_version_string(client->internal->silc_client_version,
+ &l_protocol_version, NULL, NULL,
+ NULL, NULL)) {
+ client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_AUDIT,
+ "We don't support server version `%s'",
+ version);
+ return SILC_SKE_STATUS_BAD_VERSION;
+ }
- /* Check software version */
+ /* If remote is too new, don't connect */
+ if (l_protocol_version < r_protocol_version) {
+ client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_AUDIT,
+ "We don't support server version `%s'",
+ version);
+ return SILC_SKE_STATUS_BAD_VERSION;
+ }
- if (len < strlen(silc_version_string))
- status = SILC_SKE_STATUS_BAD_VERSION;
+ ske->sock->version = r_protocol_version;
- /* XXX for now there is no other tests due to the abnormal version
- string that is used */
+ return SILC_SKE_STATUS_OK;
+}
- if (status != SILC_SKE_STATUS_OK)
- client->ops->say(client, conn,
- "We don't support server version `%s'", version);
+/* Callback that is called by the SKE to indicate that it is safe to
+ continue the execution of the protocol. 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. */
- return status;
+static void silc_client_protocol_ke_continue(SilcSKE ske,
+ void *context)
+{
+ SilcProtocol protocol = (SilcProtocol)context;
+ SilcClientKEInternalContext *ctx =
+ (SilcClientKEInternalContext *)protocol->context;
+ SilcClient client = (SilcClient)ctx->client;
+ SilcClientConnection conn = ctx->sock->user_data;
+
+ SILC_LOG_DEBUG(("Start"));
+
+ if (ske->status != SILC_SKE_STATUS_OK) {
+ /* Call failure client operation */
+ client->internal->ops->failure(client, conn, protocol,
+ (void *)ske->status);
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->schedule, 0, 0);
+ return;
+ }
+
+ /* Send Ok to the other end. We will end the protocol as server
+ sends Ok to us when we will take the new keys into use. Do this
+ if we are initiator. This is happens when this callback was sent
+ to silc_ske_initiator_finish function. */
+ if (ctx->responder == FALSE) {
+ 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, client->schedule, 0, 1);
+ }
}
/* Performs key exchange protocol. This is used for both initiator
SILC_TASK_CALLBACK(silc_client_protocol_key_exchange)
{
SilcProtocol protocol = (SilcProtocol)context;
- SilcClientKEInternalContext *ctx =
+ SilcClientKEInternalContext *ctx =
(SilcClientKEInternalContext *)protocol->context;
SilcClient client = (SilcClient)ctx->client;
SilcClientConnection conn = ctx->sock->user_data;
- SilcSKEStatus status = 0;
+ SilcSKEStatus status = SILC_SKE_STATUS_OK;
SILC_LOG_DEBUG(("Start"));
SilcSKE ske;
/* Allocate Key Exchange object */
- ske = silc_ske_alloc();
- ctx->ske = ske;
- ske->rng = client->rng;
- ske->user_data = (void *)client;
-
- if (ctx->responder == TRUE) {
-#if 0
- SilcBuffer start_payload;
+ ctx->ske = ske = silc_ske_alloc(client->rng, client);
+ silc_ske_set_callbacks(ske, ctx->send_packet, NULL,
+ ctx->verify,
+ silc_client_protocol_ke_continue,
+ silc_ske_check_version,
+ context);
+ if (ctx->responder == TRUE) {
/* Start the key exchange by processing the received security
properties packet from initiator. */
- status = silc_ske_responder_start(ske, ctx->rng, ctx->sock,
- start_payload,
- silc_client_protocol_ke_send_packet,
- context);
-#endif
+ status =
+ silc_ske_responder_start(ske, ctx->rng, ctx->sock,
+ client->internal->silc_client_version,
+ ctx->packet->buffer, TRUE);
} else {
SilcSKEStartPayload *start_payload;
/* Assemble security properties. */
- silc_ske_assemble_security_properties(ske, SILC_SKE_SP_FLAG_NONE,
- silc_version_string,
- &start_payload);
+ silc_ske_assemble_security_properties(
+ ske, SILC_SKE_SP_FLAG_MUTUAL,
+ client->internal->silc_client_version,
+ &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,
- silc_client_protocol_ke_send_packet,
- context);
+ start_payload);
}
+ /* Return now if the procedure is pending */
+ if (status == SILC_SKE_STATUS_PENDING)
+ return;
+
if (status != SILC_SKE_STATUS_OK) {
SILC_LOG_WARNING(("Error (type %d) during Key Exchange protocol",
status));
status));
protocol->state = SILC_PROTOCOL_STATE_ERROR;
- protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 0);
+ silc_protocol_execute(protocol, client->schedule, 0, 0);
return;
}
- /* Advance the state of the protocol. */
+ /* Advance protocol state and call the next state if we are responder */
protocol->state++;
+ if (ctx->responder == TRUE)
+ silc_protocol_execute(protocol, client->schedule, 0, 1);
}
break;
case 2:
{
- /*
- * Phase 1
+ /*
+ * Phase 1
*/
if (ctx->responder == TRUE) {
-#if 0
- status =
- silc_ske_responder_phase_1(ctx->ske,
- ctx->ske->start_payload,
- silc_server_protocol_ke_send_packet,
- context);
-#endif
+ /* Sends the selected security properties to the initiator. */
+ status = silc_ske_responder_phase_1(ctx->ske);
} else {
/* 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. */
- status = silc_ske_initiator_phase_1(ctx->ske, ctx->packet->buffer,
- NULL, NULL);
+ status = silc_ske_initiator_phase_1(ctx->ske, ctx->packet->buffer);
}
if (status != SILC_SKE_STATUS_OK) {
status));
protocol->state = SILC_PROTOCOL_STATE_ERROR;
- protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 0);
+ silc_protocol_execute(protocol, client->schedule, 0, 0);
return;
}
- /* Advance the state of the protocol and call the next state. */
+ /* Advance protocol state and call next state if we are initiator */
protocol->state++;
- protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 0);
+ if (ctx->responder == FALSE)
+ silc_protocol_execute(protocol, client->schedule, 0, 1);
}
break;
case 3:
{
- /*
- * Phase 2
+ /*
+ * Phase 2
*/
if (ctx->responder == TRUE) {
-#if 0
- status =
- silc_ske_responder_phase_2(ctx->ske,
- ctx->ske->start_payload,
- silc_server_protocol_ke_send_packet,
- context);
-#endif
+ /* Process the received Key Exchange 1 Payload packet from
+ the initiator. This also creates our parts of the Diffie
+ Hellman algorithm. The silc_client_protocol_ke_continue will
+ be called after the public key has been verified. */
+ 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. */
- status =
- silc_ske_initiator_phase_2(ctx->ske,
- client->public_key,
- silc_client_protocol_ke_send_packet,
- context);
+ status = silc_ske_initiator_phase_2(ctx->ske,
+ client->public_key,
+ client->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_WARNING(("Error (type %d) during Key Exchange protocol",
status));
status));
protocol->state = SILC_PROTOCOL_STATE_ERROR;
- protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 0);
+ silc_protocol_execute(protocol, client->schedule, 0, 0);
return;
}
-
- /* Advance the state of the protocol. */
- protocol->state++;
}
break;
case 4:
{
- /*
+ /*
* Finish protocol
*/
if (ctx->responder == TRUE) {
- status = 0;
-#if 0
- status =
- silc_ske_responder_phase_2(ctx->ske,
- ctx->ske->start_payload,
- silc_server_protocol_ke_send_packet,
- context);
-#endif
+ /* This creates the key exchange material and sends our
+ public parts to the initiator inside Key Exchange 2 Payload. */
+ status =
+ silc_ske_responder_finish(ctx->ske,
+ client->public_key, client->private_key,
+ SILC_SKE_PK_TYPE_SILC);
+
+ /* End the protocol on the next round */
+ protocol->state = SILC_PROTOCOL_STATE_END;
} else {
/* Finish the protocol. This verifies the Key Exchange 2 payload
- sent by responder. */
- status = silc_ske_initiator_finish(ctx->ske, ctx->packet->buffer,
- silc_client_protocol_ke_verify_key,
- context, NULL, NULL);
+ sent by responder. The silc_client_protocol_ke_continue will
+ be called after the public key has been verified. */
+ status = silc_ske_initiator_finish(ctx->ske, ctx->packet->buffer);
}
- if (status != SILC_SKE_STATUS_OK) {
+ /* Return now if the procedure is pending */
+ if (status == SILC_SKE_STATUS_PENDING)
+ return;
+ if (status != SILC_SKE_STATUS_OK) {
if (status == SILC_SKE_STATUS_UNSUPPORTED_PUBLIC_KEY) {
- client->ops->say(client, conn,
- "Received unsupported server %s public key",
- ctx->sock->hostname);
+ client->internal->ops->say(
+ client, conn, SILC_CLIENT_MESSAGE_AUDIT,
+ "Received unsupported server %s public key",
+ ctx->sock->hostname);
} else {
- client->ops->say(client, conn,
+ client->internal->ops->say(
+ client, conn, SILC_CLIENT_MESSAGE_AUDIT,
"Error during key exchange protocol with server %s",
ctx->sock->hostname);
}
protocol->state = SILC_PROTOCOL_STATE_ERROR;
- protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 0);
+ silc_protocol_execute(protocol, client->schedule, 0, 0);
return;
}
-
- /* Send Ok to the other end. We will end the protocol as server
- sends Ok to us when we will take the new keys into use. */
- silc_ske_end(ctx->ske, silc_client_protocol_ke_send_packet, context);
-
- /* End the protocol on the next round */
- protocol->state = SILC_PROTOCOL_STATE_END;
}
break;
case SILC_PROTOCOL_STATE_END:
{
- /*
+ /*
* End protocol
*/
SilcSKEKeyMaterial *keymat;
- int key_len = silc_cipher_get_key_len(ctx->ske->prop->cipher, NULL);
- int hash_len = ctx->ske->prop->hash->hash->hash_len;
+ int key_len = silc_cipher_get_key_len(ctx->ske->prop->cipher);
+ int hash_len = silc_hash_len(ctx->ske->prop->hash);
/* Process the key material */
keymat = silc_calloc(1, sizeof(*keymat));
- silc_ske_process_key_material(ctx->ske, 16, key_len, hash_len,
- keymat);
+ status = silc_ske_process_key_material(ctx->ske, 16, key_len, hash_len,
+ keymat);
+ if (status != SILC_SKE_STATUS_OK) {
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->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_ske_end(ctx->ske);
- /* Take the negotiated keys into use. */
- silc_client_protocol_ke_set_keys(ctx->ske, ctx->sock, keymat,
- ctx->ske->prop->cipher,
- ctx->ske->prop->pkcs,
- ctx->ske->prop->hash);
+ /* 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(client->schedule, ctx->timeout_task);
/* Protocol has ended, call the final callback */
if (protocol->final_callback)
- protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ silc_protocol_execute_final(protocol, client->schedule);
else
silc_protocol_free(protocol);
}
/*
* Error during protocol
*/
-
+
/* Send abort notification */
- silc_ske_abort(ctx->ske, ctx->ske->status,
- silc_client_protocol_ke_send_packet,
- context);
+ silc_ske_abort(ctx->ske, ctx->ske->status);
/* On error the final callback is always called. */
if (protocol->final_callback)
- protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ silc_protocol_execute_final(protocol, client->schedule);
else
silc_protocol_free(protocol);
break;
* 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(client->schedule, ctx->timeout_task);
+
/* On error the final callback is always called. */
if (protocol->final_callback)
- protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ silc_protocol_execute_final(protocol, client->schedule);
else
silc_protocol_free(protocol);
break;
* Connection Authentication protocol functions
*/
+static int
+silc_client_get_public_key_auth(SilcClient client,
+ SilcClientConnection conn,
+ unsigned char *auth_data,
+ SilcUInt32 *auth_data_len,
+ SilcSKE ske)
+{
+ int len;
+ SilcPKCS pkcs;
+ SilcBuffer auth;
+
+ /* Use our default key */
+ pkcs = client->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);
+
+ 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_buffer_free(auth);
+ return FALSE;
+}
+
+/* Continues the connection authentication protocol. This funtion may
+ be called directly or used as SilcAskPassphrase callback. */
+
+static void
+silc_client_conn_auth_continue(unsigned char *auth_data,
+ SilcUInt32 auth_data_len, void *context)
+{
+ SilcProtocol protocol = (SilcProtocol)context;
+ SilcClientConnAuthInternalContext *ctx =
+ (SilcClientConnAuthInternalContext *)protocol->context;
+ SilcClient client = (SilcClient)ctx->client;
+ SilcBuffer packet;
+ int payload_len = 0;
+ unsigned char *autf8 = NULL;
+
+ SILC_LOG_DEBUG(("Sending authentication to server"));
+
+ /* Passphrase must be UTF-8 encoded, if it isn't encode it */
+ if (ctx->auth_meth == SILC_AUTH_PASSWORD &&
+ !silc_utf8_valid(auth_data, auth_data_len)) {
+ payload_len = silc_utf8_encoded_len(auth_data, auth_data_len,
+ SILC_STRING_ASCII);
+ autf8 = silc_calloc(payload_len, sizeof(*autf8));
+ auth_data_len = silc_utf8_encode(auth_data, auth_data_len,
+ SILC_STRING_ASCII, autf8, payload_len);
+ auth_data = autf8;
+ }
+
+ 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(SILC_SOCKET_TYPE_CLIENT),
+ SILC_STR_UI_XNSTRING(auth_data, auth_data_len),
+ SILC_STR_END);
+
+ /* Send the packet to server */
+ silc_client_packet_send(client, ctx->sock,
+ SILC_PACKET_CONNECTION_AUTH,
+ NULL, 0, NULL, NULL,
+ packet->data, packet->len, TRUE);
+ silc_buffer_free(packet);
+ silc_free(autf8);
+
+ /* Next state is end of protocol */
+ protocol->state = SILC_PROTOCOL_STATE_END;
+}
+
SILC_TASK_CALLBACK(silc_client_protocol_connection_auth)
{
SilcProtocol protocol = (SilcProtocol)context;
- SilcClientConnAuthInternalContext *ctx =
+ SilcClientConnAuthInternalContext *ctx =
(SilcClientConnAuthInternalContext *)protocol->context;
SilcClient client = (SilcClient)ctx->client;
SilcClientConnection conn = ctx->sock->user_data;
switch(protocol->state) {
case SILC_PROTOCOL_STATE_START:
{
- /*
+ /*
* Start protocol. We send authentication data to the server
* to be authenticated.
*/
- SilcBuffer packet;
- int payload_len = 0;
unsigned char *auth_data = NULL;
- unsigned int auth_data_len = 0;
+ SilcUInt32 auth_data_len = 0;
+ unsigned char sign[1024];
switch(ctx->auth_meth) {
case SILC_AUTH_NONE:
break;
}
- client->ops->say(client, conn,
- "Password authentication required by server %s",
- ctx->sock->hostname);
- auth_data = client->ops->ask_passphrase(client, conn);
- auth_data_len = strlen(auth_data);
+ client->internal->ops->say(
+ client, conn, SILC_CLIENT_MESSAGE_INFO,
+ "Password authentication required by server %s",
+ ctx->sock->hostname);
+ client->internal->ops->ask_passphrase(client, conn,
+ silc_client_conn_auth_continue,
+ protocol);
+ return;
break;
case SILC_AUTH_PUBLIC_KEY:
- /* XXX */
+ if (!ctx->auth_data) {
+ /* Public key authentication */
+ silc_client_get_public_key_auth(client, conn, sign, &auth_data_len,
+ ctx->ske);
+ auth_data = sign;
+ } else {
+ auth_data = ctx->auth_data;
+ auth_data_len = ctx->auth_data_len;
+ }
+
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(SILC_SOCKET_TYPE_CLIENT),
- SILC_STR_UI_XNSTRING(auth_data, auth_data_len),
- SILC_STR_END);
-
- /* Send the packet to server */
- silc_client_packet_send(client, ctx->sock,
- SILC_PACKET_CONNECTION_AUTH,
- NULL, 0, NULL, NULL,
- 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;
+ silc_client_conn_auth_continue(auth_data,
+ auth_data_len, protocol);
}
break;
case SILC_PROTOCOL_STATE_END:
{
- /*
+ /*
* End protocol. Nothing special to be done here.
*/
/* Protocol has ended, call the final callback */
if (protocol->final_callback)
- protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ silc_protocol_execute_final(protocol, client->schedule);
else
silc_protocol_free(protocol);
}
case SILC_PROTOCOL_STATE_ERROR:
{
- /*
+ /*
* Error. Send notify to remote.
*/
unsigned char error[4];
/* On error the final callback is always called. */
if (protocol->final_callback)
- protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ silc_protocol_execute_final(protocol, client->schedule);
else
silc_protocol_free(protocol);
}
/* On error the final callback is always called. */
if (protocol->final_callback)
- protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ silc_protocol_execute_final(protocol, client->schedule);
else
silc_protocol_free(protocol);
break;
}
}
+/*
+ * Re-key protocol routines
+ */
+
+/* Actually takes the new keys into use. */
+
+static void
+silc_client_protocol_rekey_validate(SilcClient client,
+ SilcClientRekeyInternalContext *ctx,
+ SilcSocketConnection sock,
+ SilcSKEKeyMaterial *keymat,
+ bool send)
+{
+ SilcClientConnection conn = (SilcClientConnection)sock->user_data;
+
+ if (ctx->responder == TRUE) {
+ if (send) {
+ silc_cipher_set_key(conn->internal->send_key, keymat->receive_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->send_key, keymat->receive_iv);
+ silc_hmac_set_key(conn->internal->hmac_send, keymat->receive_hmac_key,
+ keymat->hmac_key_len);
+ } else {
+ silc_cipher_set_key(conn->internal->receive_key, keymat->send_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->receive_key, keymat->send_iv);
+ silc_hmac_set_key(conn->internal->hmac_receive, keymat->send_hmac_key,
+ keymat->hmac_key_len);
+ }
+ } else {
+ if (send) {
+ silc_cipher_set_key(conn->internal->send_key, keymat->send_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->send_key, keymat->send_iv);
+ silc_hmac_set_key(conn->internal->hmac_send, keymat->send_hmac_key,
+ keymat->hmac_key_len);
+ } else {
+ silc_cipher_set_key(conn->internal->receive_key,
+ keymat->receive_enc_key, keymat->enc_key_len);
+ silc_cipher_set_iv(conn->internal->receive_key, keymat->receive_iv);
+ silc_hmac_set_key(conn->internal->hmac_receive,
+ keymat->receive_hmac_key, keymat->hmac_key_len);
+ }
+ }
+
+ /* Save the current sending encryption key */
+ if (!send) {
+ memset(conn->internal->rekey->send_enc_key, 0,
+ conn->internal->rekey->enc_key_len);
+ silc_free(conn->internal->rekey->send_enc_key);
+ conn->internal->rekey->send_enc_key = silc_memdup(keymat->send_enc_key,
+ keymat->enc_key_len / 8);
+ conn->internal->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. */
+
+static void
+silc_client_protocol_rekey_generate(SilcClient client,
+ SilcClientRekeyInternalContext *ctx,
+ bool send)
+{
+ SilcClientConnection conn = (SilcClientConnection)ctx->sock->user_data;
+ SilcSKEKeyMaterial *keymat;
+ SilcUInt32 key_len = silc_cipher_get_key_len(conn->internal->send_key);
+ SilcUInt32 hash_len = silc_hash_len(conn->internal->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(conn->internal->rekey->send_enc_key,
+ conn->internal->rekey->enc_key_len,
+ 16, key_len, hash_len,
+ conn->internal->hash, keymat);
+
+ /* Set the keys into use */
+ silc_client_protocol_rekey_validate(client, ctx, ctx->sock, keymat, send);
+
+ silc_ske_free_key_material(keymat);
+}
+
+/* This function actually re-generates (with PFS) the keys and
+ takes them into use. */
+
+static void
+silc_client_protocol_rekey_generate_pfs(SilcClient client,
+ SilcClientRekeyInternalContext *ctx,
+ bool send)
+{
+ SilcClientConnection conn = (SilcClientConnection)ctx->sock->user_data;
+ SilcSKEKeyMaterial *keymat;
+ SilcUInt32 key_len = silc_cipher_get_key_len(conn->internal->send_key);
+ SilcUInt32 hash_len = silc_hash_len(conn->internal->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,
+ conn->internal->hash, keymat);
+
+ /* Set the keys into use */
+ silc_client_protocol_rekey_validate(client, ctx, ctx->sock, 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_client_protocol_rekey_send_packet(SilcSKE ske,
+ SilcBuffer packet,
+ SilcPacketType type,
+ void *context)
+{
+ SilcProtocol protocol = (SilcProtocol)context;
+ SilcClientRekeyInternalContext *ctx =
+ (SilcClientRekeyInternalContext *)protocol->context;
+ SilcClient client = (SilcClient)ctx->client;
+
+ /* Send the packet immediately */
+ silc_client_packet_send(client, ctx->sock, type, NULL, 0, NULL, NULL,
+ packet->data, packet->len, FALSE);
+}
+
+/* Performs re-key as defined in the SILC protocol specification. */
+
+SILC_TASK_CALLBACK(silc_client_protocol_rekey)
+{
+ SilcProtocol protocol = (SilcProtocol)context;
+ SilcClientRekeyInternalContext *ctx =
+ (SilcClientRekeyInternalContext *)protocol->context;
+ SilcClient client = (SilcClient)ctx->client;
+ SilcClientConnection conn = (SilcClientConnection)ctx->sock->user_data;
+ SilcSKEStatus status;
+
+ SILC_LOG_DEBUG(("Start"));
+
+ if (protocol->state == SILC_PROTOCOL_STATE_UNKNOWN)
+ protocol->state = SILC_PROTOCOL_STATE_START;
+
+ SILC_LOG_DEBUG(("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->type != SILC_PACKET_KEY_EXCHANGE_1) {
+ /* Error in protocol */
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->schedule, 0, 300000);
+ }
+
+ ctx->ske = silc_ske_alloc(client->rng, client);
+ ctx->ske->prop = silc_calloc(1, sizeof(*ctx->ske->prop));
+ silc_ske_group_get_by_number(conn->internal->rekey->ske_group,
+ &ctx->ske->prop->group);
+
+ silc_ske_set_callbacks(ctx->ske,
+ silc_client_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_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->schedule, 0, 300000);
+ return;
+ }
+
+ /* Advance the protocol state */
+ protocol->state++;
+ silc_protocol_execute(protocol, client->schedule, 0, 0);
+ } else {
+ /*
+ * Do normal and simple re-key.
+ */
+
+ /* Send the REKEY_DONE to indicate we will take new keys into use */
+ silc_client_packet_send(client, ctx->sock,
+ SILC_PACKET_REKEY_DONE,
+ NULL, 0, NULL, NULL, 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_client_protocol_rekey_generate(client, ctx, TRUE);
+ silc_client_packet_queue_purge(client, 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_client_packet_send(client, ctx->sock, SILC_PACKET_REKEY,
+ NULL, 0, NULL, NULL, 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(client->rng, client);
+ ctx->ske->prop = silc_calloc(1, sizeof(*ctx->ske->prop));
+ silc_ske_group_get_by_number(conn->internal->rekey->ske_group,
+ &ctx->ske->prop->group);
+
+ silc_ske_set_callbacks(ctx->ske,
+ silc_client_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_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->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_client_packet_send(client, ctx->sock,
+ SILC_PACKET_REKEY_DONE,
+ NULL, 0, NULL, NULL, 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_client_protocol_rekey_generate(client, ctx, TRUE);
+ silc_client_packet_queue_purge(client, ctx->sock);
+
+ /* The protocol ends in next stage. */
+ protocol->state = SILC_PROTOCOL_STATE_END;
+ }
+ }
+ }
+ break;
+
+ case 2:
+ /*
+ * Second state, used only when oding re-key with PFS.
+ */
+ if (ctx->responder == TRUE) {
+ if (ctx->pfs == TRUE) {
+ /*
+ * Send our KE packe 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_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->schedule, 0, 300000);
+ return;
+ }
+ }
+
+ } else {
+ if (ctx->pfs == TRUE) {
+ /*
+ * The packet type must be KE packet
+ */
+ if (ctx->packet->type != SILC_PACKET_KEY_EXCHANGE_2) {
+ /* Error in protocol */
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->schedule, 0, 300000);
+ }
+
+ status = silc_ske_initiator_finish(ctx->ske, ctx->packet->buffer);
+ if (status != SILC_SKE_STATUS_OK) {
+ SILC_LOG_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->schedule, 0, 300000);
+ return;
+ }
+ }
+ }
+
+ /* Send the REKEY_DONE to indicate we will take new keys into use
+ now. */
+ silc_client_packet_send(client, ctx->sock, SILC_PACKET_REKEY_DONE,
+ NULL, 0, NULL, NULL, 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_client_protocol_rekey_generate_pfs(client, ctx, TRUE);
+
+ /* The protocol ends in next stage. */
+ protocol->state = SILC_PROTOCOL_STATE_END;
+ break;
+
+ case SILC_PROTOCOL_STATE_END:
+ /*
+ * End protocol
+ */
+
+ if (ctx->packet->type != SILC_PACKET_REKEY_DONE) {
+ /* Error in protocol */
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ silc_protocol_execute(protocol, client->schedule, 0, 0);
+ }
+
+ /* 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_client_protocol_rekey_generate_pfs(client, ctx, FALSE);
+ else
+ silc_client_protocol_rekey_generate(client, ctx, FALSE);
+
+ /* Protocol has ended, call the final callback */
+ if (protocol->final_callback)
+ silc_protocol_execute_final(protocol, client->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);
+ }
+
+ /* On error the final callback is always called. */
+ if (protocol->final_callback)
+ silc_protocol_execute_final(protocol, client->schedule);
+ else
+ silc_protocol_free(protocol);
+ break;
+
+ case SILC_PROTOCOL_STATE_FAILURE:
+ /*
+ * We have received failure from remote
+ */
+
+ /* On error the final callback is always called. */
+ if (protocol->final_callback)
+ silc_protocol_execute_final(protocol, client->schedule);
+ else
+ silc_protocol_free(protocol);
+ break;
+
+ case SILC_PROTOCOL_STATE_UNKNOWN:
+ break;
+ }
+
+}
+
/* Registers protocols used in client */
void silc_client_protocols_register(void)
silc_client_protocol_connection_auth);
silc_protocol_register(SILC_PROTOCOL_CLIENT_KEY_EXCHANGE,
silc_client_protocol_key_exchange);
+ silc_protocol_register(SILC_PROTOCOL_CLIENT_REKEY,
+ silc_client_protocol_rekey);
}
/* Unregisters protocols */
silc_client_protocol_connection_auth);
silc_protocol_unregister(SILC_PROTOCOL_CLIENT_KEY_EXCHANGE,
silc_client_protocol_key_exchange);
+ silc_protocol_unregister(SILC_PROTOCOL_CLIENT_REKEY,
+ silc_client_protocol_rekey);
}