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-rw-r--r--crypto/aes/aes_ctr.c90
1 files changed, 6 insertions, 84 deletions
diff --git a/crypto/aes/aes_ctr.c b/crypto/aes/aes_ctr.c
index f36982be1e..7c9d165d8a 100644
--- a/crypto/aes/aes_ctr.c
+++ b/crypto/aes/aes_ctr.c
@@ -49,91 +49,13 @@
*
*/
-#ifndef AES_DEBUG
-# ifndef NDEBUG
-# define NDEBUG
-# endif
-#endif
-#include <assert.h>
-
#include <openssl/aes.h>
-#include "aes_locl.h"
-
-/* NOTE: the IV/counter CTR mode is big-endian. The rest of the AES code
- * is endian-neutral. */
-
-/* increment counter (128-bit int) by 1 */
-static void AES_ctr128_inc(unsigned char *counter) {
- unsigned long c;
-
- /* Grab bottom dword of counter and increment */
- c = GETU32(counter + 12);
- c++; c &= 0xFFFFFFFF;
- PUTU32(counter + 12, c);
-
- /* if no overflow, we're done */
- if (c)
- return;
-
- /* Grab 1st dword of counter and increment */
- c = GETU32(counter + 8);
- c++; c &= 0xFFFFFFFF;
- PUTU32(counter + 8, c);
-
- /* if no overflow, we're done */
- if (c)
- return;
-
- /* Grab 2nd dword of counter and increment */
- c = GETU32(counter + 4);
- c++; c &= 0xFFFFFFFF;
- PUTU32(counter + 4, c);
-
- /* if no overflow, we're done */
- if (c)
- return;
+#include <openssl/modes.h>
- /* Grab top dword of counter and increment */
- c = GETU32(counter + 0);
- c++; c &= 0xFFFFFFFF;
- PUTU32(counter + 0, c);
-}
-
-/* The input encrypted as though 128bit counter mode is being
- * used. The extra state information to record how much of the
- * 128bit block we have used is contained in *num, and the
- * encrypted counter is kept in ecount_buf. Both *num and
- * ecount_buf must be initialised with zeros before the first
- * call to AES_ctr128_encrypt().
- *
- * This algorithm assumes that the counter is in the x lower bits
- * of the IV (ivec), and that the application has full control over
- * overflow and the rest of the IV. This implementation takes NO
- * responsability for checking that the counter doesn't overflow
- * into the rest of the IV when incremented.
- */
void AES_ctr128_encrypt(const unsigned char *in, unsigned char *out,
- const unsigned long length, const AES_KEY *key,
- unsigned char ivec[AES_BLOCK_SIZE],
- unsigned char ecount_buf[AES_BLOCK_SIZE],
- unsigned int *num) {
-
- unsigned int n;
- unsigned long l=length;
-
- assert(in && out && key && counter && num);
- assert(*num < AES_BLOCK_SIZE);
-
- n = *num;
-
- while (l--) {
- if (n == 0) {
- AES_encrypt(ivec, ecount_buf, key);
- AES_ctr128_inc(ivec);
- }
- *(out++) = *(in++) ^ ecount_buf[n];
- n = (n+1) % AES_BLOCK_SIZE;
- }
-
- *num=n;
+ size_t length, const AES_KEY *key,
+ unsigned char ivec[AES_BLOCK_SIZE],
+ unsigned char ecount_buf[AES_BLOCK_SIZE],
+ unsigned int *num) {
+ CRYPTO_ctr128_encrypt(in,out,length,key,ivec,ecount_buf,num,(block128_f)AES_encrypt);
}