--- /dev/null
+/* ====================================================================
+ * 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/type_check.h>
+
+#include <assert.h>
+#include <string.h>
+
+#include "internal.h"
+
+
+OPENSSL_COMPILE_ASSERT((16 % sizeof(size_t)) == 0, bad_size_t_size_cfb);
+
+void CRYPTO_cfb128_encrypt(const uint8_t *in, uint8_t *out, size_t len,
+ const void *key, uint8_t ivec[16], unsigned *num,
+ int enc, block128_f block) {
+ size_t l = 0;
+
+ assert(in && out && key && ivec && num);
+
+ unsigned n = *num;
+
+ if (enc) {
+ while (n && len) {
+ *(out++) = ivec[n] ^= *(in++);
+ --len;
+ n = (n + 1) % 16;
+ }
+#if STRICT_ALIGNMENT
+ if (((uintptr_t)in | (uintptr_t)out | (uintptr_t)ivec) % sizeof(size_t) !=
+ 0) {
+ while (l < len) {
+ if (n == 0) {
+ (*block)(ivec, ivec, key);
+ }
+ out[l] = ivec[n] ^= in[l];
+ ++l;
+ n = (n + 1) % 16;
+ }
+ *num = n;
+ return;
+ }
+#endif
+ while (len >= 16) {
+ (*block)(ivec, ivec, key);
+ for (; n < 16; n += sizeof(size_t)) {
+ size_t tmp = load_word_le(ivec + n) ^ load_word_le(in + n);
+ store_word_le(ivec + n, tmp);
+ store_word_le(out + n, tmp);
+ }
+ 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;
+ } else {
+ while (n && len) {
+ uint8_t c;
+ *(out++) = ivec[n] ^ (c = *(in++));
+ ivec[n] = c;
+ --len;
+ n = (n + 1) % 16;
+ }
+ if (STRICT_ALIGNMENT &&
+ ((uintptr_t)in | (uintptr_t)out | (uintptr_t)ivec) % sizeof(size_t) !=
+ 0) {
+ while (l < len) {
+ uint8_t 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;
+ return;
+ }
+ while (len >= 16) {
+ (*block)(ivec, ivec, key);
+ for (; n < 16; n += sizeof(size_t)) {
+ size_t t = load_word_le(in + n);
+ store_word_le(out + n, load_word_le(ivec + n) ^ t);
+ store_word_le(ivec + n, t);
+ }
+ len -= 16;
+ out += 16;
+ in += 16;
+ n = 0;
+ }
+ if (len) {
+ (*block)(ivec, ivec, key);
+ while (len--) {
+ uint8_t c;
+ out[n] = ivec[n] ^ (c = in[n]);
+ ivec[n] = c;
+ ++n;
+ }
+ }
+ *num = n;
+ return;
+ }
+}
+
+
+/* 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 uint8_t *in, uint8_t *out, unsigned nbits,
+ const void *key, uint8_t ivec[16], int enc,
+ block128_f block) {
+ int n, rem, num;
+ uint8_t 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_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_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 uint8_t *in, uint8_t *out, size_t bits,
+ const void *key, uint8_t ivec[16], unsigned *num,
+ int enc, block128_f block) {
+ size_t n;
+ uint8_t c[1], d[1];
+
+ assert(in && out && key && ivec && num);
+ 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], unsigned *num, int enc,
+ block128_f block) {
+ size_t n;
+
+ assert(in && out && key && ivec && num);
+ assert(*num == 0);
+
+ for (n = 0; n < length; ++n) {
+ cfbr_encrypt_block(&in[n], &out[n], 8, key, ivec, enc, block);
+ }
+}
git://repos.xcallymotion.com / motion2.git / blobdiff