1 files changed, 316 insertions, 223 deletions

diff --git a/lib/libssl/src/crypto/rsa/rsa_eay.c b/lib/libssl/src/crypto/rsa/rsa_eay.c
index 610889dc805..bb77d0f67e9 100644
--- a/lib/libssl/src/crypto/rsa/rsa_eay.c
+++ b/lib/libssl/src/crypto/rsa/rsa_eay.c
@@ -56,7 +56,7 @@
  * [including the GNU Public Licence.]
  */
 /* ====================================================================
- * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
+ * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -115,7 +115,7 @@
 #include <openssl/rsa.h>
 #include <openssl/rand.h>
 
-#if !defined(RSA_NULL) && !defined(OPENSSL_FIPS)
+#ifndef RSA_NULL
 
 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
 		unsigned char *to, RSA *rsa,int padding);
@@ -125,7 +125,7 @@ static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
 		unsigned char *to, RSA *rsa,int padding);
 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 		unsigned char *to, RSA *rsa,int padding);
-static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa);
+static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa, BN_CTX *ctx);
 static int RSA_eay_init(RSA *rsa);
 static int RSA_eay_finish(RSA *rsa);
 static RSA_METHOD rsa_pkcs1_eay_meth={
@@ -141,7 +141,8 @@ static RSA_METHOD rsa_pkcs1_eay_meth={
 	0, /* flags */
 	NULL,
 	0, /* rsa_sign */
-	0  /* rsa_verify */
+	0, /* rsa_verify */
+	NULL /* rsa_keygen */
 	};
 
 const RSA_METHOD *RSA_PKCS1_SSLeay(void)
@@ -149,19 +150,53 @@ const RSA_METHOD *RSA_PKCS1_SSLeay(void)
 	return(&rsa_pkcs1_eay_meth);
 	}
 
+/* Usage example;
+ *    MONT_HELPER(rsa->_method_mod_p, bn_ctx, rsa->p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
+ */
+#define MONT_HELPER(method_mod, ctx, m, pre_cond, err_instr) \
+	if ((pre_cond) && ((method_mod) == NULL) && \
+			!BN_MONT_CTX_set_locked(&(method_mod), \
+				CRYPTO_LOCK_RSA, \
+				(m), (ctx))) \
+		err_instr
+
 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
 	     unsigned char *to, RSA *rsa, int padding)
 	{
-	BIGNUM f,ret;
+	BIGNUM *f,*ret;
 	int i,j,k,num=0,r= -1;
 	unsigned char *buf=NULL;
 	BN_CTX *ctx=NULL;
 
-	BN_init(&f);
-	BN_init(&ret);
+	if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS)
+		{
+		RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_MODULUS_TOO_LARGE);
+		return -1;
+		}
+
+	if (BN_ucmp(rsa->n, rsa->e) <= 0)
+		{
+		RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
+		return -1;
+		}
+
+	/* for large moduli, enforce exponent limit */
+	if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS)
+		{
+		if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS)
+			{
+			RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT, RSA_R_BAD_E_VALUE);
+			return -1;
+			}
+		}
+	
 	if ((ctx=BN_CTX_new()) == NULL) goto err;
+	BN_CTX_start(ctx);
+	f = BN_CTX_get(ctx);
+	ret = BN_CTX_get(ctx);
 	num=BN_num_bytes(rsa->n);
-	if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
+	buf = OPENSSL_malloc(num);
+	if (!f || !ret || !buf)
 		{
 		RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,ERR_R_MALLOC_FAILURE);
 		goto err;
@@ -189,37 +224,34 @@ static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
 		}
 	if (i <= 0) goto err;
 
-	if (BN_bin2bn(buf,num,&f) == NULL) goto err;
+	if (BN_bin2bn(buf,num,f) == NULL) goto err;
 	
-	if (BN_ucmp(&f, rsa->n) >= 0)
-		{	
+	if (BN_ucmp(f, rsa->n) >= 0)
+		{
 		/* usually the padding functions would catch this */
 		RSAerr(RSA_F_RSA_EAY_PUBLIC_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
 		goto err;
 		}
 
-	if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
-		{
-		if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n,
-					CRYPTO_LOCK_RSA, rsa->n, ctx))
-			goto err;
-		}
+	MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
 
-	if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
+	if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
 		rsa->_method_mod_n)) goto err;
 
 	/* put in leading 0 bytes if the number is less than the
 	 * length of the modulus */
-	j=BN_num_bytes(&ret);
-	i=BN_bn2bin(&ret,&(to[num-j]));
+	j=BN_num_bytes(ret);
+	i=BN_bn2bin(ret,&(to[num-j]));
 	for (k=0; k<(num-i); k++)
 		to[k]=0;
 
 	r=num;
 err:
-	if (ctx != NULL) BN_CTX_free(ctx);
-	BN_clear_free(&f);
-	BN_clear_free(&ret);
+	if (ctx != NULL)
+		{
+		BN_CTX_end(ctx);
+		BN_CTX_free(ctx);
+		}
 	if (buf != NULL) 
 		{
 		OPENSSL_cleanse(buf,num);
@@ -228,64 +260,101 @@ 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;
-	}
+static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx)
+{
+	BN_BLINDING *ret;
+	int got_write_lock = 0;
 
-#define BLINDING_HELPER(rsa, ctx, err_instr) \
-	do { \
-		if((!((rsa)->flags & RSA_FLAG_NO_BLINDING)) && \
-		    ((rsa)->blinding == NULL) && \
-		    !rsa_eay_blinding(rsa, ctx)) \
-		    err_instr \
-	} while(0)
+	CRYPTO_r_lock(CRYPTO_LOCK_RSA);
 
-static BN_BLINDING *setup_blinding(RSA *rsa, BN_CTX *ctx)
-	{
-	BIGNUM *A, *Ai;
-	BN_BLINDING *ret = NULL;
+	if (rsa->blinding == NULL)
+		{
+		CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
+		CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+		got_write_lock = 1;
 
-	/* added in OpenSSL 0.9.6j and 0.9.7b */
+		if (rsa->blinding == NULL)
+			rsa->blinding = RSA_setup_blinding(rsa, ctx);
+		}
 
-	/* NB: similar code appears in RSA_blinding_on (rsa_lib.c);
-	 * this should be placed in a new function of its own, but for reasons
-	 * of binary compatibility can't */
+	ret = rsa->blinding;
+	if (ret == NULL)
+		goto err;
 
-	BN_CTX_start(ctx);
-	A = BN_CTX_get(ctx);
-	if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL)
+	if (BN_BLINDING_get_thread_id(ret) == CRYPTO_thread_id())
 		{
-		/* if PRNG is not properly seeded, resort to secret exponent as unpredictable seed */
-		RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0);
-		if (!BN_pseudo_rand_range(A,rsa->n)) goto err;
+		/* rsa->blinding is ours! */
+
+		*local = 1;
 		}
 	else
 		{
-		if (!BN_rand_range(A,rsa->n)) goto err;
+		/* resort to rsa->mt_blinding instead */
+
+		*local = 0; /* instructs rsa_blinding_convert(), rsa_blinding_invert()
+		             * that the BN_BLINDING is shared, meaning that accesses
+		             * require locks, and that the blinding factor must be
+		             * stored outside the BN_BLINDING
+		             */
+
+		if (rsa->mt_blinding == NULL)
+			{
+			if (!got_write_lock)
+				{
+				CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
+				CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+				got_write_lock = 1;
+				}
+			
+			if (rsa->mt_blinding == NULL)
+				rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
+			}
+		ret = rsa->mt_blinding;
 		}
-	if ((Ai=BN_mod_inverse(NULL,A,rsa->n,ctx)) == NULL) goto err;
 
-	if (!rsa->meth->bn_mod_exp(A,A,rsa->e,rsa->n,ctx,rsa->_method_mod_n))
-		goto err;
-	ret = BN_BLINDING_new(A,Ai,rsa->n);
-	BN_free(Ai);
-err:
-	BN_CTX_end(ctx);
+ err:
+	if (got_write_lock)
+		CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+	else
+		CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
 	return ret;
-	}
+}
+
+static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
+	BIGNUM *r, BN_CTX *ctx)
+{
+	if (local)
+		return BN_BLINDING_convert_ex(f, NULL, b, ctx);
+	else
+		{
+		int ret;
+		CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
+		ret = BN_BLINDING_convert_ex(f, r, b, ctx);
+		CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
+		return ret;
+		}
+}
+
+static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
+	BIGNUM *r, BN_CTX *ctx)
+{
+	if (local)
+		return BN_BLINDING_invert_ex(f, NULL, b, ctx);
+	else
+		{
+		int ret;
+		CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
+		ret = BN_BLINDING_invert_ex(f, r, b, ctx);
+		CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
+		return ret;
+		}
+}
 
 /* signing */
 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 	     unsigned char *to, RSA *rsa, int padding)
 	{
-	BIGNUM f,ret, *res;
+	BIGNUM *f, *ret, *br, *res;
 	int i,j,k,num=0,r= -1;
 	unsigned char *buf=NULL;
 	BN_CTX *ctx=NULL;
@@ -318,8 +387,13 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 		}
 
 	if ((ctx=BN_CTX_new()) == NULL) goto err;
-	num=BN_num_bytes(rsa->n);
-	if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
+	BN_CTX_start(ctx);
+	f   = BN_CTX_get(ctx);
+	br  = BN_CTX_get(ctx);
+	ret = BN_CTX_get(ctx);
+	num = BN_num_bytes(rsa->n);
+	buf = OPENSSL_malloc(num);
+	if(!f || !ret || !buf)
 		{
 		RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,ERR_R_MALLOC_FAILURE);
 		goto err;
@@ -330,6 +404,9 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 	case RSA_PKCS1_PADDING:
 		i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
 		break;
+	case RSA_X931_PADDING:
+		i=RSA_padding_add_X931(buf,num,from,flen);
+		break;
 	case RSA_NO_PADDING:
 		i=RSA_padding_add_none(buf,num,from,flen);
 		break;
@@ -340,26 +417,18 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 		}
 	if (i <= 0) goto err;
 
-	if (BN_bin2bn(buf,num,&f) == NULL) goto err;
+	if (BN_bin2bn(buf,num,f) == NULL) goto err;
 	
-	if (BN_ucmp(&f, rsa->n) >= 0)
+	if (BN_ucmp(f, rsa->n) >= 0)
 		{	
 		/* usually the padding functions would catch this */
 		RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
 		goto err;
 		}
 
-	BLINDING_HELPER(rsa, ctx, goto err;);
-	blinding = rsa->blinding;
-	
-	/* Now unless blinding is disabled, 'blinding' is non-NULL.
-	 * But the BN_BLINDING object may be owned by some other thread
-	 * (we don't want to keep it constant and we don't want to use
-	 * lots of locking to avoid race conditions, so only a single
-	 * thread can use it; other threads have to use local blinding
-	 * factors) */
 	if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
 		{
+		blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
 		if (blinding == NULL)
 			{
 			RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
@@ -368,20 +437,8 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 		}
 	
 	if (blinding != NULL)
-		{
-		if (blinding->thread_id != CRYPTO_thread_id())
-			{
-			/* we need a local one-time blinding factor */
-
-			blinding = setup_blinding(rsa, ctx);
-			if (blinding == NULL)
-				goto err;
-			local_blinding = 1;
-			}
-		}
-
-	if (blinding)
-		if (!BN_BLINDING_convert(&f, blinding, ctx)) goto err;
+		if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
+			goto err;
 
 	if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
 		((rsa->p != NULL) &&
@@ -390,37 +447,42 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 		(rsa->dmq1 != NULL) &&
 		(rsa->iqmp != NULL)) )
 		{ 
-		if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err;
+		if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
 		}
 	else
 		{
 		BIGNUM local_d;
 		BIGNUM *d = NULL;
 		
-		if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
+		if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
 			{
 			BN_init(&local_d);
 			d = &local_d;
-			BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
+			BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
 			}
 		else
-			d = rsa->d;
-		if (!rsa->meth->bn_mod_exp(&ret,&f,d,rsa->n,ctx,NULL)) goto err;
+			d= rsa->d;
+
+		MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
+
+		if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
+				rsa->_method_mod_n)) goto err;
 		}
 
 	if (blinding)
-		if (!BN_BLINDING_invert(&ret, blinding, ctx)) goto err;
+		if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
+			goto err;
 
 	if (padding == RSA_X931_PADDING)
 		{
-		BN_sub(&f, rsa->n, &ret);
-		if (BN_cmp(&ret, &f))
-			res = &f;
+		BN_sub(f, rsa->n, ret);
+		if (BN_cmp(ret, f))
+			res = f;
 		else
-			res = &ret;
+			res = ret;
 		}
 	else
-		res = &ret;
+		res = ret;
 
 	/* put in leading 0 bytes if the number is less than the
 	 * length of the modulus */
@@ -431,11 +493,11 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 
 	r=num;
 err:
-	if (ctx != NULL) BN_CTX_free(ctx);
-	BN_clear_free(&ret);
-	BN_clear_free(&f);
-	if (local_blinding)
-		BN_BLINDING_free(blinding);
+	if (ctx != NULL)
+		{
+		BN_CTX_end(ctx);
+		BN_CTX_free(ctx);
+		}
 	if (buf != NULL)
 		{
 		OPENSSL_cleanse(buf,num);
@@ -447,7 +509,7 @@ err:
 static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 	     unsigned char *to, RSA *rsa, int padding)
 	{
-	BIGNUM f,ret;
+	BIGNUM *f, *ret, *br;
 	int j,num=0,r= -1;
 	unsigned char *p;
 	unsigned char *buf=NULL;
@@ -455,14 +517,14 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 	int local_blinding = 0;
 	BN_BLINDING *blinding = NULL;
 
-	BN_init(&f);
-	BN_init(&ret);
-	ctx=BN_CTX_new();
-	if (ctx == NULL) goto err;
-
-	num=BN_num_bytes(rsa->n);
-
-	if ((buf=(unsigned char *)OPENSSL_malloc(num)) == NULL)
+	if((ctx = BN_CTX_new()) == NULL) goto err;
+	BN_CTX_start(ctx);
+	f   = BN_CTX_get(ctx);
+	br  = BN_CTX_get(ctx);
+	ret = BN_CTX_get(ctx);
+	num = BN_num_bytes(rsa->n);
+	buf = OPENSSL_malloc(num);
+	if(!f || !ret || !buf)
 		{
 		RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,ERR_R_MALLOC_FAILURE);
 		goto err;
@@ -477,25 +539,17 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 		}
 
 	/* make data into a big number */
-	if (BN_bin2bn(from,(int)flen,&f) == NULL) goto err;
+	if (BN_bin2bn(from,(int)flen,f) == NULL) goto err;
 
-	if (BN_ucmp(&f, rsa->n) >= 0)
+	if (BN_ucmp(f, rsa->n) >= 0)
 		{
 		RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
 		goto err;
 		}
 
-	BLINDING_HELPER(rsa, ctx, goto err;);
-	blinding = rsa->blinding;
-	
-	/* Now unless blinding is disabled, 'blinding' is non-NULL.
-	 * But the BN_BLINDING object may be owned by some other thread
-	 * (we don't want to keep it constant and we don't want to use
-	 * lots of locking to avoid race conditions, so only a single
-	 * thread can use it; other threads have to use local blinding
-	 * factors) */
 	if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
 		{
+		blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
 		if (blinding == NULL)
 			{
 			RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
@@ -504,20 +558,8 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 		}
 	
 	if (blinding != NULL)
-		{
-		if (blinding->thread_id != CRYPTO_thread_id())
-			{
-			/* we need a local one-time blinding factor */
-
-			blinding = setup_blinding(rsa, ctx);
-			if (blinding == NULL)
-				goto err;
-			local_blinding = 1;
-			}
-		}
-
-	if (blinding)
-		if (!BN_BLINDING_convert(&f, blinding, ctx)) goto err;
+		if (!rsa_blinding_convert(blinding, local_blinding, f, br, ctx))
+			goto err;
 
 	/* do the decrypt */
 	if ( (rsa->flags & RSA_FLAG_EXT_PKEY) ||
@@ -527,29 +569,33 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 		(rsa->dmq1 != NULL) &&
 		(rsa->iqmp != NULL)) )
 		{
-		if (!rsa->meth->rsa_mod_exp(&ret,&f,rsa)) goto err;
+		if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx)) goto err;
 		}
 	else
 		{
 		BIGNUM local_d;
 		BIGNUM *d = NULL;
 		
-		if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
+		if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
 			{
 			d = &local_d;
-			BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
+			BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
 			}
 		else
 			d = rsa->d;
-		if (!rsa->meth->bn_mod_exp(&ret,&f,d,rsa->n,ctx,NULL))
-			goto err;
+
+		MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
+		if (!rsa->meth->bn_mod_exp(ret,f,d,rsa->n,ctx,
+				rsa->_method_mod_n))
+		  goto err;
 		}
 
 	if (blinding)
-		if (!BN_BLINDING_invert(&ret, blinding, ctx)) goto err;
+		if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
+			goto err;
 
 	p=buf;
-	j=BN_bn2bin(&ret,p); /* j is only used with no-padding mode */
+	j=BN_bn2bin(ret,p); /* j is only used with no-padding mode */
 
 	switch (padding)
 		{
@@ -575,11 +621,11 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 		RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
 
 err:
-	if (ctx != NULL) BN_CTX_free(ctx);
-	BN_clear_free(&f);
-	BN_clear_free(&ret);
-	if (local_blinding)
-		BN_BLINDING_free(blinding);
+	if (ctx != NULL)
+		{
+		BN_CTX_end(ctx);
+		BN_CTX_free(ctx);
+		}
 	if (buf != NULL)
 		{
 		OPENSSL_cleanse(buf,num);
@@ -592,7 +638,7 @@ err:
 static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
 	     unsigned char *to, RSA *rsa, int padding)
 	{
-	BIGNUM f,ret;
+	BIGNUM *f,*ret;
 	int i,num=0,r= -1;
 	unsigned char *p;
 	unsigned char *buf=NULL;
@@ -619,15 +665,14 @@ static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
 			return -1;
 			}
 		}
-
-	BN_init(&f);
-	BN_init(&ret);
-	ctx=BN_CTX_new();
-	if (ctx == NULL) goto err;
-
+	
+	if((ctx = BN_CTX_new()) == NULL) goto err;
+	BN_CTX_start(ctx);
+	f = BN_CTX_get(ctx);
+	ret = BN_CTX_get(ctx);
 	num=BN_num_bytes(rsa->n);
-	buf=(unsigned char *)OPENSSL_malloc(num);
-	if (buf == NULL)
+	buf = OPENSSL_malloc(num);
+	if(!f || !ret || !buf)
 		{
 		RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,ERR_R_MALLOC_FAILURE);
 		goto err;
@@ -641,37 +686,33 @@ static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
 		goto err;
 		}
 
-	if (BN_bin2bn(from,flen,&f) == NULL) goto err;
+	if (BN_bin2bn(from,flen,f) == NULL) goto err;
 
-	if (BN_ucmp(&f, rsa->n) >= 0)
+	if (BN_ucmp(f, rsa->n) >= 0)
 		{
 		RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
 		goto err;
 		}
 
-	/* do the decrypt */
-
-	if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
-		{
-		if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_n,
-					CRYPTO_LOCK_RSA, rsa->n, ctx))
-			goto err;
-		}
+	MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
 
-	if (!rsa->meth->bn_mod_exp(&ret,&f,rsa->e,rsa->n,ctx,
+	if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
 		rsa->_method_mod_n)) goto err;
 
-	if ((padding == RSA_X931_PADDING) && ((ret.d[0] & 0xf) != 12))
-		BN_sub(&ret, rsa->n, &ret);
+	if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
+		BN_sub(ret, rsa->n, ret);
 
 	p=buf;
-	i=BN_bn2bin(&ret,p);
+	i=BN_bn2bin(ret,p);
 
 	switch (padding)
 		{
 	case RSA_PKCS1_PADDING:
 		r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
 		break;
+	case RSA_X931_PADDING:
+		r=RSA_padding_check_X931(to,num,buf,i,num);
+		break;
 	case RSA_NO_PADDING:
 		r=RSA_padding_check_none(to,num,buf,i,num);
 		break;
@@ -683,9 +724,11 @@ static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
 		RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,RSA_R_PADDING_CHECK_FAILED);
 
 err:
-	if (ctx != NULL) BN_CTX_free(ctx);
-	BN_clear_free(&f);
-	BN_clear_free(&ret);
+	if (ctx != NULL)
+		{
+		BN_CTX_end(ctx);
+		BN_CTX_free(ctx);
+		}
 	if (buf != NULL)
 		{
 		OPENSSL_cleanse(buf,num);
@@ -694,59 +737,111 @@ err:
 	return(r);
 	}
 
-static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
+static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx)
 	{
-	BIGNUM r1,m1,vrfy;
-	BIGNUM local_dmp1, local_dmq1;
-	BIGNUM *dmp1, *dmq1;
+	BIGNUM *r1,*m1,*vrfy;
+	BIGNUM local_dmp1,local_dmq1,local_c,local_r1;
+	BIGNUM *dmp1,*dmq1,*c,*pr1;
 	int ret=0;
-	BN_CTX *ctx;
 
-	BN_init(&m1);
-	BN_init(&r1);
-	BN_init(&vrfy);
-	if ((ctx=BN_CTX_new()) == NULL) goto err;
+	BN_CTX_start(ctx);
+	r1 = BN_CTX_get(ctx);
+	m1 = BN_CTX_get(ctx);
+	vrfy = BN_CTX_get(ctx);
+
+	{
+		BIGNUM local_p, local_q;
+		BIGNUM *p = NULL, *q = NULL;
+
+		/* Make sure BN_mod_inverse in Montgomery intialization uses the
+		 * BN_FLG_CONSTTIME flag (unless RSA_FLAG_NO_CONSTTIME is set)
+		 */
+		if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
+			{
+			BN_init(&local_p);
+			p = &local_p;
+			BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);
+
+			BN_init(&local_q);
+			q = &local_q;
+			BN_with_flags(q, rsa->q, BN_FLG_CONSTTIME);
+			}
+		else
+			{
+			p = rsa->p;
+			q = rsa->q;
+			}
+
+		MONT_HELPER(rsa->_method_mod_p, ctx, p, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
+		MONT_HELPER(rsa->_method_mod_q, ctx, q, rsa->flags & RSA_FLAG_CACHE_PRIVATE, goto err);
+	}
 
-	if (rsa->flags & RSA_FLAG_CACHE_PRIVATE)
+	MONT_HELPER(rsa->_method_mod_n, ctx, rsa->n, rsa->flags & RSA_FLAG_CACHE_PUBLIC, goto err);
+
+	/* compute I mod q */
+	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
 		{
-		if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_p,
-					CRYPTO_LOCK_RSA, rsa->p, ctx))
-			goto err;
-		if (!BN_MONT_CTX_set_locked(&rsa->_method_mod_q,
-					CRYPTO_LOCK_RSA, rsa->q, ctx))
-			goto err;
+		c = &local_c;
+		BN_with_flags(c, I, BN_FLG_CONSTTIME);
+		if (!BN_mod(r1,c,rsa->q,ctx)) goto err;
+		}
+	else
+		{
+		if (!BN_mod(r1,I,rsa->q,ctx)) goto err;
 		}
 
-	if (!BN_mod(&r1,I,rsa->q,ctx)) goto err;
-	if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
+	/* compute r1^dmq1 mod q */
+	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
 		{
 		dmq1 = &local_dmq1;
-		BN_with_flags(dmq1, rsa->dmq1, BN_FLG_EXP_CONSTTIME);
+		BN_with_flags(dmq1, rsa->dmq1, BN_FLG_CONSTTIME);
 		}
 	else
 		dmq1 = rsa->dmq1;
-	if (!rsa->meth->bn_mod_exp(&m1,&r1,dmq1,rsa->q,ctx,
+	if (!rsa->meth->bn_mod_exp(m1,r1,dmq1,rsa->q,ctx,
 		rsa->_method_mod_q)) goto err;
 
-	if (!BN_mod(&r1,I,rsa->p,ctx)) goto err;
-	if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
+	/* compute I mod p */
+	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
+		{
+		c = &local_c;
+		BN_with_flags(c, I, BN_FLG_CONSTTIME);
+		if (!BN_mod(r1,c,rsa->p,ctx)) goto err;
+		}
+	else
+		{
+		if (!BN_mod(r1,I,rsa->p,ctx)) goto err;
+		}
+
+	/* compute r1^dmp1 mod p */
+	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
 		{
 		dmp1 = &local_dmp1;
-		BN_with_flags(dmp1, rsa->dmp1, BN_FLG_EXP_CONSTTIME);
+		BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
 		}
 	else
 		dmp1 = rsa->dmp1;
-	if (!rsa->meth->bn_mod_exp(r0,&r1,dmp1,rsa->p,ctx,
+	if (!rsa->meth->bn_mod_exp(r0,r1,dmp1,rsa->p,ctx,
 		rsa->_method_mod_p)) goto err;
 
-	if (!BN_sub(r0,r0,&m1)) goto err;
+	if (!BN_sub(r0,r0,m1)) goto err;
 	/* This will help stop the size of r0 increasing, which does
 	 * affect the multiply if it optimised for a power of 2 size */
-	if (r0->neg)
+	if (BN_is_negative(r0))
 		if (!BN_add(r0,r0,rsa->p)) goto err;
 
-	if (!BN_mul(&r1,r0,rsa->iqmp,ctx)) goto err;
-	if (!BN_mod(r0,&r1,rsa->p,ctx)) goto err;
+	if (!BN_mul(r1,r0,rsa->iqmp,ctx)) goto err;
+
+	/* Turn BN_FLG_CONSTTIME flag on before division operation */
+	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
+		{
+		pr1 = &local_r1;
+		BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
+		}
+	else
+		pr1 = r1;
+	if (!BN_mod(r0,pr1,rsa->p,ctx)) goto err;
+
 	/* If p < q it is occasionally possible for the correction of
          * adding 'p' if r0 is negative above to leave the result still
 	 * negative. This can break the private key operations: the following
@@ -754,23 +849,23 @@ static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
 	 * This will *never* happen with OpenSSL generated keys because
          * they ensure p > q [steve]
          */
-	if (r0->neg)
+	if (BN_is_negative(r0))
 		if (!BN_add(r0,r0,rsa->p)) goto err;
-	if (!BN_mul(&r1,r0,rsa->q,ctx)) goto err;
-	if (!BN_add(r0,&r1,&m1)) goto err;
+	if (!BN_mul(r1,r0,rsa->q,ctx)) goto err;
+	if (!BN_add(r0,r1,m1)) goto err;
 
 	if (rsa->e && rsa->n)
 		{
-		if (!rsa->meth->bn_mod_exp(&vrfy,r0,rsa->e,rsa->n,ctx,NULL)) goto err;
+		if (!rsa->meth->bn_mod_exp(vrfy,r0,rsa->e,rsa->n,ctx,rsa->_method_mod_n)) goto err;
 		/* If 'I' was greater than (or equal to) rsa->n, the operation
 		 * will be equivalent to using 'I mod n'. However, the result of
 		 * the verify will *always* be less than 'n' so we don't check
 		 * for absolute equality, just congruency. */
-		if (!BN_sub(&vrfy, &vrfy, I)) goto err;
-		if (!BN_mod(&vrfy, &vrfy, rsa->n, ctx)) goto err;
-		if (vrfy.neg)
-			if (!BN_add(&vrfy, &vrfy, rsa->n)) goto err;
-		if (!BN_is_zero(&vrfy))
+		if (!BN_sub(vrfy, vrfy, I)) goto err;
+		if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) goto err;
+		if (BN_is_negative(vrfy))
+			if (!BN_add(vrfy, vrfy, rsa->n)) goto err;
+		if (!BN_is_zero(vrfy))
 			{
 			/* 'I' and 'vrfy' aren't congruent mod n. Don't leak
 			 * miscalculated CRT output, just do a raw (slower)
@@ -779,22 +874,20 @@ static int RSA_eay_mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa)
 			BIGNUM local_d;
 			BIGNUM *d = NULL;
 		
-			if (!(rsa->flags & RSA_FLAG_NO_EXP_CONSTTIME))
+			if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
 				{
 				d = &local_d;
-				BN_with_flags(d, rsa->d, BN_FLG_EXP_CONSTTIME);
+				BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
 				}
 			else
 				d = rsa->d;
-			if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,NULL)) goto err;
+			if (!rsa->meth->bn_mod_exp(r0,I,d,rsa->n,ctx,
+						   rsa->_method_mod_n)) goto err;
 			}
 		}
 	ret=1;
 err:
-	BN_clear_free(&m1);
-	BN_clear_free(&r1);
-	BN_clear_free(&vrfy);
-	BN_CTX_free(ctx);
+	BN_CTX_end(ctx);
 	return(ret);
 	}