Commit 66e1081a authored by Ben Laurie's avatar Ben Laurie
Browse files

Blinding fix.

parent ef42d6a4

CHANGES

+6 −0
Original line number Diff line number Diff line
@@ -10,6 +10,12 @@ 
     in ssl3_get_client_key_exchange (ssl/s3_srvr.c).

     [Bodo Moeller]



  *) Turn on RSA blinding by default, to avoid a timing attack. Applications

     that don't want it can call RSA_blinding_off(). They would be ill-advised

     to do so in most cases. The automatic enabling can also be turned off

     by defining OPENSSL_FORCE_NO_RSA_BLINDING at compile-time.

     [Ben Laurie, Steve Henson, Geoff Thorpe]



 Changes between 0.9.6h and 0.9.6i  [19 Feb 2003]



  *) In ssl3_get_record (ssl/s3_pkt.c), minimize information leaked

crypto/rsa/rsa_eay.c

+23 −4
Original line number Diff line number Diff line
@@ -190,6 +190,25 @@ err: 
	return(r);

	}



static int rsa_eay_blinding(RSA *rsa, BN_CTX *ctx)

	{

	int ret = 1;

	CRYPTO_w_lock(CRYPTO_LOCK_RSA);

	/* Check again inside the lock - the macro's check is racey */

	if(rsa->blinding == NULL)

		ret = RSA_blinding_on(rsa, ctx);

	CRYPTO_w_unlock(CRYPTO_LOCK_RSA);

	return ret;

	}



#define BLINDING_HELPER(rsa, ctx, err_instr) \

	do { \

		if(((rsa)->flags & RSA_FLAG_BLINDING) && \

				((rsa)->blinding == NULL) && \

				!rsa_eay_blinding(rsa, ctx)) \

			err_instr \

	} while(0)



/* signing */

static int RSA_eay_private_encrypt(int flen, unsigned char *from,

	     unsigned char *to, RSA *rsa, int padding)
@@ -234,8 +253,8 @@ static int RSA_eay_private_encrypt(int flen, unsigned char *from, 
		goto err;

		}



	if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))

		RSA_blinding_on(rsa,ctx);

	BLINDING_HELPER(rsa, ctx, goto err;);



	if (rsa->flags & RSA_FLAG_BLINDING)

		if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
@@ -313,8 +332,8 @@ static int RSA_eay_private_decrypt(int flen, unsigned char *from, 
		goto err;

		}



	if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))

		RSA_blinding_on(rsa,ctx);

	BLINDING_HELPER(rsa, ctx, goto err;);



	if (rsa->flags & RSA_FLAG_BLINDING)

		if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;

crypto/rsa/rsa_lib.c

+7 −1
Original line number Diff line number Diff line
@@ -71,7 +71,13 @@ static STACK_OF(CRYPTO_EX_DATA_FUNCS) *rsa_meth=NULL; 


RSA *RSA_new(void)

	{

	return(RSA_new_method(NULL));

	RSA *r=RSA_new_method(NULL);



#ifndef OPENSSL_NO_FORCE_RSA_BLINDING

	r->flags|=RSA_FLAG_BLINDING;

#endif



	return r;

	}



void RSA_set_default_method(RSA_METHOD *meth)