| /* ==================================================================== |
| * 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 <openssl/opensslconf.h> |
| #if !defined(OPENSSL_SYS_STARBOARD) |
| #include <assert.h> |
| #include <string.h> |
| #endif // !defined(OPENSSL_SYS_STARBOARD) |
| |
| #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; |
| |
| OPENSSL_port_assert(in && out && key && ivec && num); |
| |
| n = *num; |
| |
| if (enc) { |
| #if !defined(OPENSSL_SMALL_FOOTPRINT) |
| if (16 % sizeof(size_t) == 0) { /* always true actually */ |
| do { |
| while (n && len) { |
| *(out++) = ivec[n] ^= *(in++); |
| --len; |
| n = (n + 1) % 16; |
| } |
| # if defined(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) { /* always true actually */ |
| do { |
| while (n && len) { |
| unsigned char c; |
| *(out++) = ivec[n] ^ (c = *(in++)); |
| ivec[n] = c; |
| --len; |
| n = (n + 1) % 16; |
| } |
| # if defined(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 */ |
| OPENSSL_port_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) |
| OPENSSL_port_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]; |
| |
| OPENSSL_port_assert(in && out && key && ivec && num); |
| OPENSSL_port_assert(*num == 0); |
| |
| 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; |
| |
| OPENSSL_port_assert(in && out && key && ivec && num); |
| OPENSSL_port_assert(*num == 0); |
| |
| for (n = 0; n < length; ++n) |
| cfbr_encrypt_block(&in[n], &out[n], 8, key, ivec, enc, block); |
| } |
