X-Git-Url: http://git.silcnet.org/gitweb/?a=blobdiff_plain;f=lib%2Fsilcclient%2Fprotocol.c;h=da7bc07fb352423627398550db7c670bd609cb86;hb=386c883d8774999c6e74d7c6c37e52e4163a4cb1;hp=c50c2318c23e5959aaa76f9b8d776afcc5bd3638;hpb=5530203f8f8ebca913311c9d9cee5eeced9a9d22;p=silc.git diff --git a/lib/silcclient/protocol.c b/lib/silcclient/protocol.c index c50c2318..da7bc07f 100644 --- a/lib/silcclient/protocol.c +++ b/lib/silcclient/protocol.c @@ -23,11 +23,11 @@ /* $Id$ */ #include "clientlibincludes.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 @@ -35,10 +35,10 @@ extern char *silc_version_string; /* 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 = @@ -48,85 +48,131 @@ static void silc_client_protocol_ke_send_packet(SilcSKE ske, /* 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, + uint32 pk_len, + SilcSKEPKType pk_type, + void *context, + SilcSKEVerifyCbCompletion completion, + void *completion_context) { SilcProtocol protocol = (SilcProtocol)context; 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; 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); + silc_hmac_alloc((char *)silc_hmac_get_name(hmac), NULL, &conn->hmac_send); + silc_hmac_alloc((char *)silc_hmac_get_name(hmac), NULL, &conn->hmac_receive); + + if (is_responder == TRUE) { + silc_cipher_set_key(conn->send_key, keymat->receive_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->send_key, keymat->receive_iv); + silc_cipher_set_key(conn->receive_key, keymat->send_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->receive_key, keymat->send_iv); + silc_hmac_set_key(conn->hmac_send, keymat->receive_hmac_key, + keymat->hmac_key_len); + silc_hmac_set_key(conn->hmac_receive, keymat->send_hmac_key, + keymat->hmac_key_len); + } else { + silc_cipher_set_key(conn->send_key, keymat->send_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->send_key, keymat->send_iv); + silc_cipher_set_key(conn->receive_key, keymat->receive_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->receive_key, keymat->receive_iv); + silc_hmac_set_key(conn->hmac_send, keymat->send_hmac_key, + keymat->hmac_key_len); + silc_hmac_set_key(conn->hmac_receive, keymat->receive_hmac_key, + keymat->hmac_key_len); + } - 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); + /* Rekey stuff */ + conn->rekey = silc_calloc(1, sizeof(*conn->rekey)); + conn->rekey->send_enc_key = silc_memdup(keymat->send_enc_key, + keymat->enc_key_len / 8); + conn->rekey->enc_key_len = keymat->enc_key_len / 8; + + if (ske->start_payload->flags & SILC_SKE_SP_FLAG_PFS) + conn->rekey->pfs = TRUE; + conn->rekey->ske_group = silc_ske_group_get_number(group); + + /* Save the HASH function */ + silc_hash_alloc(hash->hash->name, &conn->hash); } /* Checks the version string of the server. */ SilcSKEStatus silc_ske_check_version(SilcSKE ske, unsigned char *version, - unsigned int len) + uint32 len, void *context) { SilcClientConnection conn = (SilcClientConnection)ske->sock->user_data; SilcClient client = (SilcClient)ske->user_data; SilcSKEStatus status = SILC_SKE_STATUS_OK; + char *cp; + int maj = 0, min = 0, build = 0, maj2 = 0, min2 = 0, build2 = 0; /* Check for initial version string */ if (!strstr(version, "SILC-1.0-")) @@ -134,19 +180,96 @@ SilcSKEStatus silc_ske_check_version(SilcSKE ske, unsigned char *version, /* Check software version */ - if (len < strlen(silc_version_string)) + cp = version + 9; + if (!cp) + status = SILC_SKE_STATUS_BAD_VERSION; + + maj = atoi(cp); + cp = strchr(cp, '.'); + if (cp) { + min = atoi(cp + 1); + cp++; + } + cp = strchr(cp, '.'); + if (cp) + build = atoi(cp + 1); + + cp = client->internal->silc_client_version + 9; + if (!cp) + status = SILC_SKE_STATUS_BAD_VERSION; + + maj2 = atoi(cp); + cp = strchr(cp, '.'); + if (cp) { + min2 = atoi(cp + 1); + cp++; + } + cp = strchr(cp, '.'); + if (cp) + build2 = atoi(cp + 1); + + if (maj != maj2) status = SILC_SKE_STATUS_BAD_VERSION; - /* XXX for now there is no other tests due to the abnormal version - string that is used */ + /* XXX backward support for 0.6.1 */ + if (maj == 0 && min == 6 && build < 2) + ske->backward_version = 1; if (status != SILC_SKE_STATUS_OK) - client->ops->say(client, conn, - "We don't support server version `%s'", version); + client->internal->ops->say(client, conn, SILC_CLIENT_MESSAGE_AUDIT, + "We don't support server version `%s'", + version); return status; } +/* 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. */ + +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, 100000); + } +} + /* Performs key exchange protocol. This is used for both initiator and responder key exchange. This may be called recursively. */ @@ -157,7 +280,7 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) (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")); @@ -173,39 +296,40 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) SilcSKE ske; /* Allocate Key Exchange object */ - ske = silc_ske_alloc(); - ctx->ske = ske; - ske->rng = client->rng; - ske->user_data = (void *)client; + 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) { -#if 0 - SilcBuffer start_payload; - - /* 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)); @@ -213,12 +337,14 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) 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, 100000); } break; case 2: @@ -227,20 +353,14 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) * 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) { @@ -250,13 +370,14 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) 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, 100000); } break; case 3: @@ -265,24 +386,26 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) * 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)); @@ -290,12 +413,9 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) 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: @@ -304,44 +424,42 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) * Finish protocol */ if (ctx->responder == TRUE) { - status = 0; -#if 0 + /* This creates the key exchange material and sends our + public parts to the initiator inside Key Exchange 2 Payload. */ status = - silc_ske_responder_phase_2(ctx->ske, - ctx->ske->start_payload, - silc_server_protocol_ke_send_packet, - context); -#endif + 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; @@ -351,23 +469,35 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) * End protocol */ SilcSKEKeyMaterial *keymat; - int key_len = silc_cipher_get_key_len(ctx->ske->prop->cipher, NULL); + int key_len = silc_cipher_get_key_len(ctx->ske->prop->cipher); int hash_len = ctx->ske->prop->hash->hash->hash_len; /* 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); } @@ -379,13 +509,11 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) */ /* 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; @@ -395,9 +523,15 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) * 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; @@ -410,6 +544,77 @@ SILC_TASK_CALLBACK(silc_client_protocol_key_exchange) * Connection Authentication protocol functions */ +static int +silc_client_get_public_key_auth(SilcClient client, + SilcClientConnection conn, + unsigned char *auth_data, + uint32 *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, + uint32 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; + + SILC_LOG_DEBUG(("Start")); + + 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); + + /* Next state is end of protocol */ + protocol->state = SILC_PROTOCOL_STATE_END; +} + SILC_TASK_CALLBACK(silc_client_protocol_connection_auth) { SilcProtocol protocol = (SilcProtocol)context; @@ -430,10 +635,9 @@ SILC_TASK_CALLBACK(silc_client_protocol_connection_auth) * 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; + uint32 auth_data_len = 0; + unsigned char sign[1024]; switch(ctx->auth_meth) { case SILC_AUTH_NONE: @@ -448,41 +652,32 @@ SILC_TASK_CALLBACK(silc_client_protocol_connection_auth) 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; @@ -494,7 +689,7 @@ SILC_TASK_CALLBACK(silc_client_protocol_connection_auth) /* 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); } @@ -516,7 +711,7 @@ SILC_TASK_CALLBACK(silc_client_protocol_connection_auth) /* 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); } @@ -528,7 +723,7 @@ SILC_TASK_CALLBACK(silc_client_protocol_connection_auth) /* 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; @@ -538,6 +733,403 @@ SILC_TASK_CALLBACK(silc_client_protocol_connection_auth) } } +/* + * 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->send_key, keymat->receive_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->send_key, keymat->receive_iv); + silc_hmac_set_key(conn->hmac_send, keymat->receive_hmac_key, + keymat->hmac_key_len); + } else { + silc_cipher_set_key(conn->receive_key, keymat->send_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->receive_key, keymat->send_iv); + silc_hmac_set_key(conn->hmac_receive, keymat->send_hmac_key, + keymat->hmac_key_len); + } + } else { + if (send) { + silc_cipher_set_key(conn->send_key, keymat->send_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->send_key, keymat->send_iv); + silc_hmac_set_key(conn->hmac_send, keymat->send_hmac_key, + keymat->hmac_key_len); + } else { + silc_cipher_set_key(conn->receive_key, keymat->receive_enc_key, + keymat->enc_key_len); + silc_cipher_set_iv(conn->receive_key, keymat->receive_iv); + silc_hmac_set_key(conn->hmac_receive, keymat->receive_hmac_key, + keymat->hmac_key_len); + } + } + + /* Save the current sending encryption key */ + if (!send) { + memset(conn->rekey->send_enc_key, 0, conn->rekey->enc_key_len); + silc_free(conn->rekey->send_enc_key); + conn->rekey->send_enc_key = silc_memdup(keymat->send_enc_key, + keymat->enc_key_len / 8); + conn->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; + uint32 key_len = silc_cipher_get_key_len(conn->send_key); + uint32 hash_len = conn->hash->hash->hash_len; + + 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->rekey->send_enc_key, + conn->rekey->enc_key_len, + 16, key_len, hash_len, + conn->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; + uint32 key_len = silc_cipher_get_key_len(conn->send_key); + uint32 hash_len = conn->hash->hash->hash_len; + unsigned char *tmpbuf; + uint32 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->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->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); + + /* 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->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); + + /* 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 */ + 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) @@ -546,6 +1138,8 @@ 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 */ @@ -556,4 +1150,6 @@ void silc_client_protocols_unregister(void) 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); }