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Diffstat (limited to 'ext/libressl/crypto/modes/cfb128.c')
| -rw-r--r-- | ext/libressl/crypto/modes/cfb128.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/ext/libressl/crypto/modes/cfb128.c b/ext/libressl/crypto/modes/cfb128.c new file mode 100644 index 0000000..88bfbc4 --- /dev/null +++ b/ext/libressl/crypto/modes/cfb128.c @@ -0,0 +1,234 @@ +/* $OpenBSD: cfb128.c,v 1.4 2015/02/10 09:46:30 miod Exp $ */ +/* ==================================================================== + * Copyright (c) 2008 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. + * ==================================================================== + * + */ + +#include <openssl/crypto.h> +#include "modes_lcl.h" +#include <string.h> + +#ifndef MODES_DEBUG +# ifndef NDEBUG +# define NDEBUG +# endif +#endif + +/* The input and output encrypted as though 128bit cfb mode is being + * used. The extra state information to record how much of the + * 128bit block we have used is contained in *num; + */ +void CRYPTO_cfb128_encrypt(const unsigned char *in, unsigned char *out, + size_t len, const void *key, + unsigned char ivec[16], int *num, + int enc, block128_f block) +{ + unsigned int n; + size_t l = 0; + + n = *num; + + if (enc) { +#if !defined(OPENSSL_SMALL_FOOTPRINT) + if (16%sizeof(size_t) == 0) do { /* always true actually */ + while (n && len) { + *(out++) = ivec[n] ^= *(in++); + --len; + n = (n+1) % 16; + } +#ifdef __STRICT_ALIGNMENT + if (((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) + break; +#endif + while (len>=16) { + (*block)(ivec, ivec, key); + for (; n<16; n+=sizeof(size_t)) { + *(size_t*)(out+n) = + *(size_t*)(ivec+n) ^= *(size_t*)(in+n); + } + len -= 16; + out += 16; + in += 16; + n = 0; + } + if (len) { + (*block)(ivec, ivec, key); + while (len--) { + out[n] = ivec[n] ^= in[n]; + ++n; + } + } + *num = n; + return; + } while (0); + /* the rest would be commonly eliminated by x86* compiler */ +#endif + while (l<len) { + if (n == 0) { + (*block)(ivec, ivec, key); + } + out[l] = ivec[n] ^= in[l]; + ++l; + n = (n+1) % 16; + } + *num = n; + } else { +#if !defined(OPENSSL_SMALL_FOOTPRINT) + if (16%sizeof(size_t) == 0) do { /* always true actually */ + while (n && len) { + unsigned char c; + *(out++) = ivec[n] ^ (c = *(in++)); ivec[n] = c; + --len; + n = (n+1) % 16; + } +#ifdef __STRICT_ALIGNMENT + if (((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) + break; +#endif + while (len>=16) { + (*block)(ivec, ivec, key); + for (; n<16; n+=sizeof(size_t)) { + size_t t = *(size_t*)(in+n); + *(size_t*)(out+n) = *(size_t*)(ivec+n) ^ t; + *(size_t*)(ivec+n) = t; + } + len -= 16; + out += 16; + in += 16; + n = 0; + } + if (len) { + (*block)(ivec, ivec, key); + while (len--) { + unsigned char c; + out[n] = ivec[n] ^ (c = in[n]); ivec[n] = c; + ++n; + } + } + *num = n; + return; + } while (0); + /* the rest would be commonly eliminated by x86* compiler */ +#endif + while (l<len) { + unsigned char c; + if (n == 0) { + (*block)(ivec, ivec, key); + } + out[l] = ivec[n] ^ (c = in[l]); ivec[n] = c; + ++l; + n = (n+1) % 16; + } + *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 */ +static void cfbr_encrypt_block(const unsigned char *in,unsigned char *out, + int nbits,const void *key, + unsigned char ivec[16],int enc, + block128_f block) +{ + int n,rem,num; + unsigned char ovec[16*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,16); + /* construct the new IV */ + (*block)(ivec,ivec,key); + num = (nbits+7)/8; + if (enc) /* encrypt the input */ + for(n=0 ; n < num ; ++n) + out[n] = (ovec[16+n] = in[n] ^ ivec[n]); + else /* decrypt the input */ + for(n=0 ; n < num ; ++n) + out[n] = (ovec[16+n] = in[n]) ^ ivec[n]; + /* shift ovec left... */ + rem = nbits%8; + num = nbits/8; + if(rem==0) + memcpy(ivec,ovec+num,16); + else + for(n=0 ; n < 16 ; ++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 CRYPTO_cfb128_1_encrypt(const unsigned char *in, unsigned char *out, + size_t bits, const void *key, + unsigned char ivec[16], int *num, + int enc, block128_f block) +{ + size_t n; + unsigned char c[1],d[1]; + + for(n=0 ; n<bits ; ++n) + { + c[0]=(in[n/8]&(1 << (7-n%8))) ? 0x80 : 0; + cfbr_encrypt_block(c,d,1,key,ivec,enc,block); + out[n/8]=(out[n/8]&~(1 << (unsigned int)(7-n%8))) | + ((d[0]&0x80) >> (unsigned int)(n%8)); + } +} + +void CRYPTO_cfb128_8_encrypt(const unsigned char *in, unsigned char *out, + size_t length, const void *key, + unsigned char ivec[16], int *num, + int enc, block128_f block) +{ + size_t n; + + for(n=0 ; n<length ; ++n) + cfbr_encrypt_block(&in[n],&out[n],8,key,ivec,enc,block); +} + |