/* $OpenBSD: d1_enc.c,v 1.11 2016/03/06 14:52:15 beck Exp $ */ /* * DTLS implementation written by Nagendra Modadugu * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. */ /* ==================================================================== * Copyright (c) 1998-2005 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). * */ /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * 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 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 acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS 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 AUTHOR OR 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. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ #include #include "ssl_locl.h" #include #include #include /* dtls1_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|, respectively. * * Returns: * 0: (in non-constant time) if the record is publically invalid (i.e. too * short etc). * 1: if the record's padding is valid / the encryption was successful. * -1: if the record's padding/AEAD-authenticator is invalid or, if sending, * an internal error occured. */ int dtls1_enc(SSL *s, int send) { SSL3_RECORD *rec; EVP_CIPHER_CTX *ds; unsigned long l; int bs, i, j, k, mac_size = 0; const EVP_CIPHER *enc; if (send) { if (EVP_MD_CTX_md(s->write_hash)) { mac_size = EVP_MD_CTX_size(s->write_hash); if (mac_size < 0) return -1; } ds = s->enc_write_ctx; rec = &(s->s3->wrec); if (s->enc_write_ctx == NULL) enc = NULL; else { enc = EVP_CIPHER_CTX_cipher(s->enc_write_ctx); if (rec->data != rec->input) { #ifdef DEBUG /* we can't write into the input stream */ fprintf(stderr, "%s:%d: rec->data != rec->input\n", __FILE__, __LINE__); #endif } else if (EVP_CIPHER_block_size(ds->cipher) > 1) { arc4random_buf(rec->input, EVP_CIPHER_block_size(ds->cipher)); } } } else { if (EVP_MD_CTX_md(s->read_hash)) { mac_size = EVP_MD_CTX_size(s->read_hash); OPENSSL_assert(mac_size >= 0); } ds = s->enc_read_ctx; rec = &(s->s3->rrec); if (s->enc_read_ctx == NULL) enc = NULL; else enc = EVP_CIPHER_CTX_cipher(s->enc_read_ctx); } if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) { memmove(rec->data, rec->input, rec->length); rec->input = rec->data; } else { l = rec->length; bs = EVP_CIPHER_block_size(ds->cipher); if ((bs != 1) && send) { i = bs - ((int)l % bs); /* Add weird padding of upto 256 bytes */ /* we need to add 'i' padding bytes of value j */ j = i - 1; for (k = (int)l; k < (int)(l + i); k++) rec->input[k] = j; l += i; rec->length += i; } if (!send) { if (l == 0 || l % bs != 0) return 0; } EVP_Cipher(ds, rec->data, rec->input, l); if ((bs != 1) && !send) return tls1_cbc_remove_padding(s, rec, bs, mac_size); } return (1); }