Commit cfdbff23 authored by Andy Polyakov's avatar Andy Polyakov
Browse files

bn_exp.c: improve portability.

parent f7eb0ab9

crypto/bn/bn_exp.c

+6 −1
Original line number Diff line number Diff line
@@ -654,16 +654,21 @@ int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, const BIGNUM *p, 
	numPowers = 1 << window;

	powerbufLen = sizeof(m->d[0])*(top*numPowers +

				(top>numPowers?top:numPowers));

#ifdef alloca

	if (powerbufLen < 3072)

		powerbufFree = alloca(powerbufLen+MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH);

	else if ((powerbufFree=(unsigned char*)OPENSSL_malloc(powerbufLen+MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH)) == NULL)

	else

#endif

	if ((powerbufFree=(unsigned char*)OPENSSL_malloc(powerbufLen+MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH)) == NULL)

		goto err;

		

	powerbuf = MOD_EXP_CTIME_ALIGN(powerbufFree);

	memset(powerbuf, 0, powerbufLen);



#ifdef alloca

	if (powerbufLen < 3072)

		powerbufFree = NULL;

#endif



	computeTemp.d = (BN_ULONG *)(powerbuf + sizeof(m->d[0])*top*numPowers);

	computeTemp.top = computeTemp.dmax = top;