/* crypto/aes/aes_cfb.c -*- mode:C; c-file-style: "eay" -*- */
/* ====================================================================
- * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
+ * Copyright (c) 2002-2006 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
* ====================================================================
*
*/
-/* 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.]
- */
#ifndef AES_DEBUG
# ifndef NDEBUG
#include <openssl/aes.h>
#include "aes_locl.h"
+#include "e_os.h"
+
+#define STRICT_ALIGNMENT
+#if defined(__i386) || defined(__i386__) || \
+ defined(__x86_64) || defined(__x86_64__) || \
+ defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64)
+# undef STRICT_ALIGNMENT
+#endif
/* The input and output encrypted as though 128bit cfb mode is being
* used. The extra state information to record how much of the
*/
void AES_cfb128_encrypt(const unsigned char *in, unsigned char *out,
- const unsigned long length, const AES_KEY *key,
+ unsigned long length, const AES_KEY *key,
unsigned char *ivec, int *num, const int enc) {
- unsigned int n;
- unsigned long l = length;
- unsigned char c;
+ unsigned int n;
+ unsigned long l = 0;
+
+ assert(in && out && key && ivec && num);
+
+ n = *num;
- assert(in && out && key && ivec && num);
+#if !defined(OPENSSL_SMALL_FOOTPRINT)
+ if (AES_BLOCK_SIZE%sizeof(size_t) == 0) { /* always true actually */
+ if (enc) {
+ if (n) {
+ while (length) {
+ *(out++) = ivec[n] ^= *(in++);
+ length--;
+ if(!(n = (n + 1) % AES_BLOCK_SIZE))
+ break;
+ }
+ }
+#if defined(STRICT_ALIGNMENT)
+ if (((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0)
+ goto enc_unaligned;
+#endif
+ while ((l + AES_BLOCK_SIZE) <= length) {
+ unsigned int i;
+ AES_encrypt(ivec, ivec, key);
+ for (i=0;i<AES_BLOCK_SIZE;i+=sizeof(size_t)) {
+ *(size_t*)(out+l+i) =
+ *(size_t*)(ivec+i) ^= *(size_t*)(in+l+i);
+ }
+ l += AES_BLOCK_SIZE;
+ }
+
+ if (l < length) {
+ AES_encrypt(ivec, ivec, key);
+ do { out[l] = ivec[n] ^= in[l];
+ l++; n++;
+ } while (l < length);
+ }
+ } else {
+ if (n) {
+ while (length) {
+ unsigned char c;
+ *(out++) = ivec[n] ^ (c = *(in++)); ivec[n] = c;
+ length--;
+ if(!(n = (n + 1) % AES_BLOCK_SIZE))
+ break;
+ }
+ }
+#if defined(STRICT_ALIGNMENT)
+ if (((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0)
+ goto dec_unaligned;
+#endif
+ while (l + AES_BLOCK_SIZE <= length) {
+ unsigned int i;
+ AES_encrypt(ivec, ivec, key);
+ for (i=0;i<AES_BLOCK_SIZE;i+=sizeof(size_t)) {
+ size_t t = *(size_t*)(in+l+i);
+ *(size_t*)(out+l+i) = *(size_t*)(ivec+i) ^ t;
+ *(size_t*)(ivec+i) = t;
+ }
+ l += AES_BLOCK_SIZE;
+ }
- n = *num;
+ if (l < length) {
+ AES_encrypt(ivec, ivec, key);
+ do { unsigned char c;
+ out[l] = ivec[n] ^ (c = in[l]); ivec[n] = c;
+ l++; n++;
+ } while (l < length);
+ }
+ }
+ *num = n;
+ return;
+ }
+#endif
+ /* this code would be commonly eliminated by x86* compiler */
if (enc) {
- while (l--) {
+#if defined(STRICT_ALIGNMENT) && !defined(OPENSSL_SMALL_FOOTPRINT)
+ enc_unaligned:
+#endif
+ while (l<length) {
if (n == 0) {
AES_encrypt(ivec, ivec, key);
}
- ivec[n] = *(out++) = *(in++) ^ ivec[n];
+ out[l] = ivec[n] ^= in[l];
+ l++;
n = (n+1) % AES_BLOCK_SIZE;
}
} else {
- while (l--) {
+#if defined(STRICT_ALIGNMENT) && !defined(OPENSSL_SMALL_FOOTPRINT)
+ dec_unaligned:
+#endif
+ while (l<length) {
+ unsigned char c;
if (n == 0) {
AES_encrypt(ivec, ivec, key);
}
- c = *(in);
- *(out++) = *(in++) ^ ivec[n];
- ivec[n] = c;
+ out[l] = ivec[n] ^ (c = in[l]); ivec[n] = c;
+ l++;
n = (n+1) % AES_BLOCK_SIZE;
}
}
*num=n;
}
+/* This expects a single block of size nbits for both in and out. Note that
+ it corrupts any extra bits in the last byte of out */
+void AES_cfbr_encrypt_block(const unsigned char *in,unsigned char *out,
+ const int nbits,const AES_KEY *key,
+ unsigned char *ivec,const int enc)
+ {
+ int n,rem,num;
+ unsigned char ovec[AES_BLOCK_SIZE*2 + 1]; /* +1 because we dererefence (but don't use) one byte off the end */
+
+ if (nbits<=0 || nbits>128) return;
+
+ /* fill in the first half of the new IV with the current IV */
+ memcpy(ovec,ivec,AES_BLOCK_SIZE);
+ /* construct the new IV */
+ AES_encrypt(ivec,ivec,key);
+ num = (nbits+7)/8;
+ if (enc) /* encrypt the input */
+ for(n=0 ; n < num ; ++n)
+ out[n] = (ovec[AES_BLOCK_SIZE+n] = in[n] ^ ivec[n]);
+ else /* decrypt the input */
+ for(n=0 ; n < num ; ++n)
+ out[n] = (ovec[AES_BLOCK_SIZE+n] = in[n]) ^ ivec[n];
+ /* shift ovec left... */
+ rem = nbits%8;
+ num = nbits/8;
+ if(rem==0)
+ memcpy(ivec,ovec+num,AES_BLOCK_SIZE);
+ else
+ for(n=0 ; n < AES_BLOCK_SIZE ; ++n)
+ ivec[n] = ovec[n+num]<<rem | ovec[n+num+1]>>(8-rem);
+
+ /* it is not necessary to cleanse ovec, since the IV is not secret */
+ }
+
+/* N.B. This expects the input to be packed, MS bit first */
+void AES_cfb1_encrypt(const unsigned char *in, unsigned char *out,
+ const unsigned long length, const AES_KEY *key,
+ unsigned char *ivec, int *num, const int enc)
+ {
+ unsigned int n;
+ unsigned char c[1],d[1];
+
+ assert(in && out && key && ivec && num);
+ assert(*num == 0);
+
+ memset(out,0,(length+7)/8);
+ for(n=0 ; n < length ; ++n)
+ {
+ c[0]=(in[n/8]&(1 << (7-n%8))) ? 0x80 : 0;
+ AES_cfbr_encrypt_block(c,d,1,key,ivec,enc);
+ out[n/8]=(out[n/8]&~(1 << (7-n%8)))|((d[0]&0x80) >> (n%8));
+ }
+ }
+
+void AES_cfb8_encrypt(const unsigned char *in, unsigned char *out,
+ const unsigned long length, const AES_KEY *key,
+ unsigned char *ivec, int *num, const int enc)
+ {
+ unsigned int n;
+
+ assert(in && out && key && ivec && num);
+ assert(*num == 0);
+
+ for(n=0 ; n < length ; ++n)
+ AES_cfbr_encrypt_block(&in[n],&out[n],8,key,ivec,enc);
+ }
+
projects / openssl.git / blobdiff