Commit a45bd295 authored by Bodo Möller's avatar Bodo Möller
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Document BN_mod_mul_montgomery bug; 

make disabled code slightly more correct (this does not solve
the problem though).
parent 688fbf54

CHANGES

+4 −0
Original line number Diff line number Diff line
@@ -4,6 +4,10 @@ 


 Changes between 0.9.5a and 0.9.6  [xx XXX 2000]



  *) Disable optimized squaring variant in BN_mod_mul_montgomery,

     it can return incorrect results.

     [Bodo Moeller]



  *) Disable the check for content being present when verifying detached

     signatures in pk7_smime.c. Some versions of Netscape (wrongly)

     include zero length content when signing messages.

crypto/bn/bn_mont.c

+3 −2
Original line number Diff line number Diff line
@@ -85,7 +85,8 @@ int BN_mod_mul_montgomery(BIGNUM *r, BIGNUM *a, BIGNUM *b, 


	if (a == b)

		{

#if 0 /* buggy -- try squaring  g  in the following parameters

#if 0 /* buggy -- try squaring  g  (after converting it to Montgomery

         representation) in the following parameters

         (but note that squaring 2 or 4 works):

Diffie-Hellman-Parameters: (1024 bit)

    prime:
@@ -109,7 +110,7 @@ Sgh5jjQE3e+VGbPNOkMbMCsKbfJfFDdP4TVtbVHCReSFtXZiXn7G9ExC6aY37WsL 
		bn_wexpand(tmp2,a->top*4);

		bn_sqr_recursive(tmp->d,a->d,a->top,tmp2->d);

		tmp->top=a->top*2;

		if (tmp->top > 0 && tmp->d[tmp->top-1] == 0)

		while (tmp->top > 0 && tmp->d[tmp->top-1] == 0)

			tmp->top--;

#else

		if (!BN_sqr(tmp,a,ctx)) goto err;