Commit 6d82a206 authored by Bodo Möller's avatar Bodo Möller
Browse files

Fix BN_[pseudo_]rand: 'mask' must be used even if top=-1. 

Mention BN_[pseudo_]rand with top=-1 in CHANGES.
parent 6c66fcba

CHANGES

+3 −0
Original line number Diff line number Diff line
@@ -39,6 +39,9 @@ 


  *) Add new function BN_rand_range(), and fix DSA_sign_setup() to prevent

     Bleichenbacher's DSA attack.

     Extend BN_[pseudo_]rand: As before, top=1 forces the highest two bits

     to be set and top=0 forces the highest bit to be set; top=-1 is new

     and leaves the highest bit random.

     [Ulf Moeller]



  *) In the NCONF_...-based implementations for CONF_... queries

crypto/bn/bn_rand.c

+5 −7
Original line number Diff line number Diff line
@@ -76,7 +76,7 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom) 


	bytes=(bits+7)/8;

	bit=(bits-1)%8;

	mask=0xff<<bit;

	mask=0xff<<(bit+1);



	buf=(unsigned char *)OPENSSL_malloc(bytes);

	if (buf == NULL)
@@ -112,16 +112,15 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom) 
			else

				{

				buf[0]|=(3<<(bit-1));

				buf[0]&= ~(mask<<1);

				}

			}

		else

			{

			buf[0]|=(1<<bit);

			buf[0]&= ~(mask<<1);

			}

		}

	if (bottom) /* set bottom bits to whatever odd is */

	buf[0] &= ~mask;

	if (bottom) /* set bottom bit if requested */

		buf[bytes-1]|=1;

	if (!BN_bin2bn(buf,bytes,rnd)) goto err;

	ret=1;
@@ -194,4 +193,3 @@ int BN_rand_range(BIGNUM *r, BIGNUM *range) 


	return 1;

	}