/* ssl/d1_enc.c */
/*
* 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 <stdio.h>
#include "ssl_locl.h"
#include <openssl/comp.h>
#include <openssl/evp.h>
#include <openssl/hmac.h>
#include <openssl/md5.h>
#include <openssl/rand.h>
int dtls1_enc(SSL *s, int send)
{
SSL3_RECORD *rec;
EVP_CIPHER_CTX *ds;
unsigned long l;
int bs,i,ii,j,k,n=0;
const EVP_CIPHER *enc;
if (send)
{
if (s->write_hash != NULL)
n=EVP_MD_size(s->write_hash);
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)
/* we can't write into the input stream */
fprintf(stderr, "%s:%d: rec->data != rec->input\n",
__FILE__, __LINE__);
else if ( EVP_CIPHER_block_size(ds->cipher) > 1)
{
if (!RAND_bytes(rec->input, EVP_CIPHER_block_size(ds->cipher)))
return -1;
}
}
}
else
{
if (s->read_hash != NULL)
n=EVP_MD_size(s->read_hash);
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);
}
#ifdef KSSL_DEBUG
printf("dtls1_enc(%d)\n", send);
#endif /* KSSL_DEBUG */
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;
if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG)
{
if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
j++;
}
for (k=(int)l; k<(int)(l+i); k++)
rec->input[k]=j;
l+=i;
rec->length+=i;
}
#ifdef KSSL_DEBUG
{
unsigned long ui;
printf("EVP_Cipher(ds=%p,rec->data=%p,rec->input=%p,l=%ld) ==>\n",
ds,rec->data,rec->input,l);
printf("\tEVP_CIPHER_CTX: %d buf_len, %d key_len [%d %d], %d iv_len\n",
ds->buf_len, ds->cipher->key_len,
DES_KEY_SZ, DES_SCHEDULE_SZ,
ds->cipher->iv_len);
printf("\t\tIV: ");
for (i=0; i<ds->cipher->iv_len; i++) printf("%02X", ds->iv[i]);
printf("\n");
printf("\trec->input=");
for (ui=0; ui<l; ui++) printf(" %02x", rec->input[ui]);
printf("\n");
}
#endif /* KSSL_DEBUG */
if (!send)
{
if (l == 0 || l%bs != 0)
{
SSLerr(SSL_F_DTLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_DECRYPTION_FAILED);
return 0;
}
}
EVP_Cipher(ds,rec->data,rec->input,l);
#ifdef KSSL_DEBUG
{
unsigned long i;
printf("\trec->data=");
for (i=0; i<l; i++)
printf(" %02x", rec->data[i]); printf("\n");
}
#endif /* KSSL_DEBUG */
if ((bs != 1) && !send)
{
ii=i=rec->data[l-1]; /* padding_length */
i++;
if (s->options&SSL_OP_TLS_BLOCK_PADDING_BUG)
{
/* First packet is even in size, so check */
if ((memcmp(s->s3->read_sequence,
"\0\0\0\0\0\0\0\0",8) == 0) && !(ii & 1))
s->s3->flags|=TLS1_FLAGS_TLS_PADDING_BUG;
if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
i--;
}
/* TLS 1.0 does not bound the number of padding bytes by the block size.
* All of them must have value 'padding_length'. */
if (i > (int)rec->length)
{
/* Incorrect padding. SSLerr() and ssl3_alert are done
* by caller: we don't want to reveal whether this is
* a decryption error or a MAC verification failure
* (see http://www.openssl.org/~bodo/tls-cbc.txt)
*/
return -1;
}
for (j=(int)(l-i); j<(int)l; j++)
{
if (rec->data[j] != ii)
{
/* Incorrect padding */
return -1;
}
}
rec->length-=i;
rec->data += bs; /* skip the implicit IV */
rec->input += bs;
rec->length -= bs;
}
}
return(1);
}