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Diffstat (limited to 'openssl/crypto/modes/cfb128.c')
-rw-r--r--openssl/crypto/modes/cfb128.c292
1 files changed, 152 insertions, 140 deletions
diff --git a/openssl/crypto/modes/cfb128.c b/openssl/crypto/modes/cfb128.c
index 4e6f5d35e..d4ecbd08e 100644
--- a/openssl/crypto/modes/cfb128.c
+++ b/openssl/crypto/modes/cfb128.c
@@ -6,7 +6,7 @@
* are met:
*
* 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
+ * 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
@@ -59,14 +59,15 @@
#endif
#include <assert.h>
-/* 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;
+/*
+ * 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)
+ size_t len, const void *key,
+ unsigned char ivec[16], int *num,
+ int enc, block128_f block)
{
unsigned int n;
size_t l = 0;
@@ -77,166 +78,177 @@ void CRYPTO_cfb128_encrypt(const unsigned char *in, unsigned char *out,
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;
- }
-#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 */
+ 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;
+ 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;
- }
-#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 */
+ 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;
+ 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)
+/*
+ * 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);
+ 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 bits, const void *key,
+ unsigned char ivec[16], int *num,
+ int enc, block128_f block)
{
size_t n;
- unsigned char c[1],d[1];
+ unsigned char 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));
- }
+ 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 length, const void *key,
+ unsigned char ivec[16], int *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);
+ for (n = 0; n < length; ++n)
+ cfbr_encrypt_block(&in[n], &out[n], 8, key, ivec, enc, block);
}
-
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