/* * DTLS implementation written by Nagendra Modadugu * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. */ /* ==================================================================== * Copyright (c) 1999-2005 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" * * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to * endorse or promote products derived from this software without * prior written permission. For written permission, please contact * openssl-core@OpenSSL.org. * * 5. Products derived from this software may not be called "OpenSSL" * nor may "OpenSSL" appear in their names without prior written * permission of the OpenSSL Project. * * 6. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" * * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * This product includes cryptographic software written by Eric Young * (eay@cryptsoft.com). This product includes software written by Tim * Hudson (tjh@cryptsoft.com). */ #include #include #include #include #include #include "internal.h" static uint16_t dtls1_version_from_wire(uint16_t wire_version) { uint16_t tls_version = ~wire_version; uint16_t version = tls_version + 0x0201; /* If either component overflowed, clamp it so comparisons still work. */ if ((version >> 8) < (tls_version >> 8)) { version = 0xff00 | (version & 0xff); } if ((version & 0xff) < (tls_version & 0xff)) { version = (version & 0xff00) | 0xff; } /* DTLS 1.0 maps to TLS 1.1, not TLS 1.0. */ if (version == TLS1_VERSION) { version = TLS1_1_VERSION; } return version; } static uint16_t dtls1_version_to_wire(uint16_t version) { assert(version >= TLS1_1_VERSION); /* DTLS 1.0 maps to TLS 1.1, not TLS 1.0. */ if (version == TLS1_1_VERSION) { return DTLS1_VERSION; } return ~(version - 0x0201); } static int dtls1_begin_handshake(SSL *ssl) { return 1; } static void dtls1_finish_handshake(SSL *ssl) { ssl->d1->handshake_read_seq = 0; ssl->d1->handshake_write_seq = 0; dtls_clear_incoming_messages(ssl); ssl->init_msg = NULL; ssl->init_num = 0; } static int dtls1_set_read_state(SSL *ssl, SSL_AEAD_CTX *aead_ctx) { /* Cipher changes are illegal when there are buffered incoming messages. */ if (dtls_has_incoming_messages(ssl)) { OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFERED_MESSAGES_ON_CIPHER_CHANGE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE); SSL_AEAD_CTX_free(aead_ctx); return 0; } ssl->d1->r_epoch++; memset(&ssl->d1->bitmap, 0, sizeof(ssl->d1->bitmap)); memset(ssl->s3->read_sequence, 0, sizeof(ssl->s3->read_sequence)); SSL_AEAD_CTX_free(ssl->s3->aead_read_ctx); ssl->s3->aead_read_ctx = aead_ctx; return 1; } static int dtls1_set_write_state(SSL *ssl, SSL_AEAD_CTX *aead_ctx) { ssl->d1->w_epoch++; memcpy(ssl->d1->last_write_sequence, ssl->s3->write_sequence, sizeof(ssl->s3->write_sequence)); memset(ssl->s3->write_sequence, 0, sizeof(ssl->s3->write_sequence)); SSL_AEAD_CTX_free(ssl->s3->aead_write_ctx); ssl->s3->aead_write_ctx = aead_ctx; return 1; } static const SSL_PROTOCOL_METHOD kDTLSProtocolMethod = { 1 /* is_dtls */, TLS1_1_VERSION, TLS1_2_VERSION, dtls1_version_from_wire, dtls1_version_to_wire, dtls1_new, dtls1_free, dtls1_begin_handshake, dtls1_finish_handshake, dtls1_get_message, dtls1_hash_current_message, dtls1_read_app_data, dtls1_read_change_cipher_spec, dtls1_read_close_notify, dtls1_write_app_data, dtls1_dispatch_alert, dtls1_supports_cipher, dtls1_init_message, dtls1_finish_message, dtls1_write_message, dtls1_send_change_cipher_spec, dtls1_expect_flight, dtls1_received_flight, dtls1_set_read_state, dtls1_set_write_state, }; const SSL_METHOD *DTLS_method(void) { static const SSL_METHOD kMethod = { 0, &kDTLSProtocolMethod, }; return &kMethod; } /* Legacy version-locked methods. */ const SSL_METHOD *DTLSv1_2_method(void) { static const SSL_METHOD kMethod = { DTLS1_2_VERSION, &kDTLSProtocolMethod, }; return &kMethod; } const SSL_METHOD *DTLSv1_method(void) { static const SSL_METHOD kMethod = { DTLS1_VERSION, &kDTLSProtocolMethod, }; return &kMethod; } /* Legacy side-specific methods. */ const SSL_METHOD *DTLSv1_2_server_method(void) { return DTLSv1_2_method(); } const SSL_METHOD *DTLSv1_server_method(void) { return DTLSv1_method(); } const SSL_METHOD *DTLSv1_2_client_method(void) { return DTLSv1_2_method(); } const SSL_METHOD *DTLSv1_client_method(void) { return DTLSv1_method(); } const SSL_METHOD *DTLS_server_method(void) { return DTLS_method(); } const SSL_METHOD *DTLS_client_method(void) { return DTLS_method(); }