[OpenSEED-CVSlog] [Commit] openseed/src seed_ofb.c

[Chang <pe...@us...>]

perky       01/11/15 22:13:32

  Modified:    src      seed_ofb.c
  Log:
  correct OFB encrypt IV handling
  
  Revision  Changes    Path
  1.3       +13 -15    openseed/src/seed_ofb.c
  
  Index: seed_ofb.c
  ===================================================================
  RCS file: /cvsroot/openseed/openseed/src/seed_ofb.c,v
  retrieving revision 1.2
  retrieving revision 1.3
  diff -u -r1.2 -r1.3
  --- seed_ofb.c	2001/11/16 04:37:11	1.2
  +++ seed_ofb.c	2001/11/16 06:13:31	1.3
  @@ -25,7 +25,7 @@
    * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    * SUCH DAMAGE.
    *
  - *     $Id: seed_ofb.c,v 1.2 2001/11/16 04:37:11 perky Exp $
  + *     $Id: seed_ofb.c,v 1.3 2001/11/16 06:13:31 perky Exp $
    */
   
   #include <stdlib.h>
  @@ -40,44 +40,42 @@
   seed_ofb_encrypt(const unsigned char *in, unsigned char *out, size_t length,
   					SEED_KEY_SCHEDULE ks, SEED_IV iv)
   {
  -	const unsigned char *prev, *e_in=in+length;
  +	const unsigned char *e_in=in+length;
  +	unsigned char prev[SEED_BLOCK];
   
   	/* XXX: check block size */
  -	if (!iv)	prev = NULLIV;
  -	else		prev = iv;
  +	if (!iv)    { MOV_SEEDBLOCK(prev, NULLIV); }
  +	else        { MOV_SEEDBLOCK(prev, iv); }
   
   	for(; in < e_in; in += SEED_BLOCK, out += SEED_BLOCK) {
  -		seed_encrypt(out, in, ks);
  -		XOR_SEEDBLOCK(out, out, prev);
  -		prev = out;
  +		seed_encrypt(prev, prev, ks);
  +		XOR_SEEDBLOCK(out, prev, in);
   	}
   
   	if (iv)	{
   		MOV_SEEDBLOCK(iv, prev);
   	}
  -	/* XXX: Padding ?? */
   }
   
   void
   seed_ofb_decrypt(const unsigned char *in, unsigned char *out, size_t length,
   					SEED_KEY_SCHEDULE ks, SEED_IV iv)
   {
  -	const unsigned char *prev, *e_in=in+length;
  +	const unsigned char *e_in=in+length;
  +	unsigned char prev[SEED_BLOCK];
   
   	/* XXX: check block size */
  -	if (!iv)	prev = NULLIV;
  -	else		prev = iv;
  +	if (!iv)    { MOV_SEEDBLOCK(prev, NULLIV); }
  +	else        { MOV_SEEDBLOCK(prev, iv); }
   
   	for(; in < e_in; in += SEED_BLOCK, out += SEED_BLOCK) {
  -		XOR_SEEDBLOCK(out, in, prev);
  -		seed_decrypt(out, out, ks);
  -		prev = in;
  +		seed_encrypt(prev, prev, ks);
  +		XOR_SEEDBLOCK(out, prev, in);
   	}
   
   	if (iv)	{
   		MOV_SEEDBLOCK(iv, prev);
   	}
  -	/* XXX: Padding ?? */
   }
   
   /*