Hide BN_CTX structure details.

Incease the number of BIGNUMs in a BN_CTX.

CHANGES

@@ -3,6 +3,10 @@
 
  Changes between 0.9.6 and 0.9.7  [xx XXX 2000]
 
+  *) Hide BN_CTX structure details in bn_lcl.h instead of publishing them
+     in <openssl/bn.h>.  Also further increase BN_CTX_NUM to 24.
+     [Bodo Moeller]
+
   *) Modify EVP_Digest*() routines so they now return values. Although the
      internal software routines can never fail additional hardware versions
      might.

crypto/bn/bn.h

@@ -238,18 +238,8 @@ typedef struct bignum_st
 	int flags;
 	} BIGNUM;
 
-/* Used for temp variables */
-#define BN_CTX_NUM	20
-#define BN_CTX_NUM_POS	12
-typedef struct bignum_ctx
-	{
-	int tos;
-	BIGNUM bn[BN_CTX_NUM];
-	int flags;
-	int depth;
-	int pos[BN_CTX_NUM_POS];
-	int too_many;
-	} BN_CTX;
+/* Used for temp variables (declaration hidden in bn_lcl.h) */
+typedef struct bignum_ctx BN_CTX;
 
 typedef struct bn_blinding_st
 	{

crypto/bn/bn_ctx.c

@@ -61,8 +61,9 @@
 
 #include <stdio.h>
 #include <assert.h>
+
 #include "cryptlib.h"
-#include <openssl/bn.h>
+#include "bn_lcl.h"
 
 
 BN_CTX *BN_CTX_new(void)
@@ -83,6 +84,7 @@ BN_CTX *BN_CTX_new(void)
 
 void BN_CTX_init(BN_CTX *ctx)
 	{
+#if 0 /* explicit version */
 	int i;
 	ctx->tos = 0;
 	ctx->flags = 0;
@@ -90,6 +92,9 @@ void BN_CTX_init(BN_CTX *ctx)
 	ctx->too_many = 0;
 	for (i = 0; i < BN_CTX_NUM; i++)
 		BN_init(&(ctx->bn[i]));
+#else
+	memset(ctx, 0, sizeof *ctx);
+#endif
 	}
 
 void BN_CTX_free(BN_CTX *ctx)

crypto/bn/bn_lcl.h

@@ -119,6 +119,20 @@ extern "C" {
 #endif
 
 
+/* Used for temp variables */
+#define BN_CTX_NUM	24
+#define BN_CTX_NUM_POS	12
+struct bignum_ctx
+	{
+	int tos;
+	BIGNUM bn[BN_CTX_NUM];
+	int flags;
+	int depth;
+	int pos[BN_CTX_NUM_POS];
+	int too_many;
+	} /* BN_CTX */;
+
+
 /*
  * BN_window_bits_for_exponent_size -- macro for sliding window mod_exp functions
  *

crypto/bn/bntest.c

@@ -485,9 +485,11 @@ int test_mul(BIO *bp)
 	{
 	BIGNUM a,b,c,d,e;
 	int i;
-	BN_CTX ctx;
+	BN_CTX *ctx;
+
+	ctx = BN_CTX_new();
+	if (ctx == NULL) exit(1);
 	
-	BN_CTX_init(&ctx);
 	BN_init(&a);
 	BN_init(&b);
 	BN_init(&c);
@@ -505,7 +507,7 @@ int test_mul(BIO *bp)
 			BN_bntest_rand(&b,i-num1,0,0);
 		a.neg=rand_neg();
 		b.neg=rand_neg();
-		BN_mul(&c,&a,&b,&ctx);
+		BN_mul(&c,&a,&b,ctx);
 		if (bp != NULL)
 			{
 			if (!results)
@@ -518,7 +520,7 @@ int test_mul(BIO *bp)
 			BN_print(bp,&c);
 			BIO_puts(bp,"\n");
 			}
-		BN_div(&d,&e,&c,&a,&ctx);
+		BN_div(&d,&e,&c,&a,ctx);
 		BN_sub(&d,&d,&b);
 		if(!BN_is_zero(&d) || !BN_is_zero(&e))
 		    {
@@ -531,7 +533,7 @@ int test_mul(BIO *bp)
 	BN_free(&c);
 	BN_free(&d);
 	BN_free(&e);
-	BN_CTX_free(&ctx);
+	BN_CTX_free(ctx);
 	return(1);
 	}
 

crypto/dh/dh_key.c

@@ -101,11 +101,12 @@ const DH_METHOD *DH_OpenSSL(void)
 static int generate_key(DH *dh)
 	{
 	int ok=0;
-	BN_CTX ctx;
+	BN_CTX *ctx;
 	BN_MONT_CTX *mont;
 	BIGNUM *pub_key=NULL,*priv_key=NULL;
 
-	BN_CTX_init(&ctx);
+	ctx = BN_CTX_new();
+	if (ctx == NULL) goto err;
 
 	if (dh->priv_key == NULL)
 		{
@@ -130,12 +131,12 @@ static int generate_key(DH *dh)
 		{
 		if ((dh->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
 			if (!BN_MONT_CTX_set((BN_MONT_CTX *)dh->method_mont_p,
-				dh->p,&ctx)) goto err;
+				dh->p,ctx)) goto err;
 		}
 	mont=(BN_MONT_CTX *)dh->method_mont_p;
 
 	if (!ENGINE_get_DH(dh->engine)->bn_mod_exp(dh, pub_key, dh->g,
-				priv_key,dh->p,&ctx,mont))
+				priv_key,dh->p,ctx,mont))
 		goto err;
 		
 	dh->pub_key=pub_key;
@@ -147,20 +148,21 @@ err:
 
 	if ((pub_key != NULL)  && (dh->pub_key == NULL))  BN_free(pub_key);
 	if ((priv_key != NULL) && (dh->priv_key == NULL)) BN_free(priv_key);
-	BN_CTX_free(&ctx);
+	BN_CTX_free(ctx);
 	return(ok);
 	}
 
 static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
 	{
-	BN_CTX ctx;
+	BN_CTX *ctx;
 	BN_MONT_CTX *mont;
 	BIGNUM *tmp;
 	int ret= -1;
 
-	BN_CTX_init(&ctx);
-	BN_CTX_start(&ctx);
-	tmp = BN_CTX_get(&ctx);
+	ctx = BN_CTX_new();
+	if (ctx == NULL) goto err;
+	BN_CTX_start(ctx);
+	tmp = BN_CTX_get(ctx);
 	
 	if (dh->priv_key == NULL)
 		{
@@ -171,12 +173,12 @@ static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
 		{
 		if ((dh->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
 			if (!BN_MONT_CTX_set((BN_MONT_CTX *)dh->method_mont_p,
-				dh->p,&ctx)) goto err;
+				dh->p,ctx)) goto err;
 		}
 
 	mont=(BN_MONT_CTX *)dh->method_mont_p;
 	if (!ENGINE_get_DH(dh->engine)->bn_mod_exp(dh, tmp, pub_key,
-				dh->priv_key,dh->p,&ctx,mont))
+				dh->priv_key,dh->p,ctx,mont))
 		{
 		DHerr(DH_F_DH_COMPUTE_KEY,ERR_R_BN_LIB);
 		goto err;
@@ -184,8 +186,8 @@ static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
 
 	ret=BN_bn2bin(tmp,key);
 err:
-	BN_CTX_end(&ctx);
-	BN_CTX_free(&ctx);
+	BN_CTX_end(ctx);
+	BN_CTX_free(ctx);
 	return(ret);
 	}
 

crypto/engine/engine_openssl.c

@@ -129,6 +129,7 @@ static int openssl_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 	BN_init(&r1);
 	/* BN_mul() cannot accept const BIGNUMs so I use the BN_CTX
 	 * to duplicate what I need. <sigh> */
+	BN_CTX_start(bn_ctx);
 	if ((temp_bn = BN_CTX_get(bn_ctx)) == NULL) goto err;
 	if (!BN_copy(temp_bn, iqmp)) goto err;
  
@@ -166,8 +167,7 @@ static int openssl_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 err:
 	BN_clear_free(&m1);
 	BN_clear_free(&r1);
-	if (temp_bn)
-		bn_ctx->tos--;
+	BN_CTX_end(ctx);
 	if (!ctx)
 		BN_CTX_free(bn_ctx);
 	return(ret);

crypto/engine/hw_atalla.c

@@ -318,11 +318,12 @@ static int atalla_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 		goto err;
 	}
 	/* Prepare the params */
+	BN_CTX_start(ctx);
 	modulus = BN_CTX_get(ctx);
 	exponent = BN_CTX_get(ctx);
 	argument = BN_CTX_get(ctx);
 	result = BN_CTX_get(ctx);
-	if(!modulus || !exponent || !argument || !result)
+	if (!result)
 	{
 		ENGINEerr(ENGINE_F_ATALLA_MOD_EXP,ENGINE_R_BN_CTX_FULL);
 		goto err;
@@ -360,10 +361,7 @@ static int atalla_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 	BN_bin2bn((unsigned char *)result->d, numbytes, r);
 	to_return = 1;
 err:
-	if(modulus) ctx->tos--;
-	if(exponent) ctx->tos--;
-	if(argument) ctx->tos--;
-	if(result) ctx->tos--;
+	BN_CTX_end(ctx);
 	return to_return;
 	}
 

crypto/engine/hw_cswift.c

@@ -358,11 +358,12 @@ static int cswift_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 		}
 	acquired = 1;
 	/* Prepare the params */
+	BN_CTX_start(ctx);
 	modulus = BN_CTX_get(ctx);
 	exponent = BN_CTX_get(ctx);
 	argument = BN_CTX_get(ctx);
 	result = BN_CTX_get(ctx);
-	if(!modulus || !exponent || !argument || !result)
+	if(!result)
 		{
 		ENGINEerr(ENGINE_F_CSWIFT_MOD_EXP,ENGINE_R_BN_CTX_FULL);
 		goto err;
@@ -421,10 +422,7 @@ static int cswift_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 err:
 	if(acquired)
 		release_context(hac);
-	if(modulus) ctx->tos--;
-	if(exponent) ctx->tos--;
-	if(argument) ctx->tos--;
-	if(result) ctx->tos--;
+	BN_CTX_end(ctx);
 	return to_return;
 	}
 
@@ -454,6 +452,7 @@ static int cswift_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 		}
 	acquired = 1;
 	/* Prepare the params */
+	BN_CTX_start(ctx);
 	rsa_p = BN_CTX_get(ctx);
 	rsa_q = BN_CTX_get(ctx);
 	rsa_dmp1 = BN_CTX_get(ctx);
@@ -461,8 +460,7 @@ static int cswift_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 	rsa_iqmp = BN_CTX_get(ctx);
 	argument = BN_CTX_get(ctx);
 	result = BN_CTX_get(ctx);
-	if(!rsa_p || !rsa_q || !rsa_dmp1 || !rsa_dmq1 || !rsa_iqmp ||
-			!argument || !result)
+	if(!result)
 		{
 		ENGINEerr(ENGINE_F_CSWIFT_MOD_EXP_CRT,ENGINE_R_BN_CTX_FULL);
 		goto err;
@@ -532,13 +530,7 @@ static int cswift_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 err:
 	if(acquired)
 		release_context(hac);
-	if(rsa_p) ctx->tos--;
-	if(rsa_q) ctx->tos--;
-	if(rsa_dmp1) ctx->tos--;
-	if(rsa_dmq1) ctx->tos--;
-	if(rsa_iqmp) ctx->tos--;
-	if(argument) ctx->tos--;
-	if(result) ctx->tos--;
+	BN_CTX_end(ctx);
 	return to_return;
 	}
  
@@ -594,12 +586,13 @@ static DSA_SIG *cswift_dsa_sign(const unsigned char *dgst, int dlen, DSA *dsa)
 		}
 	acquired = 1;
 	/* Prepare the params */
+	BN_CTX_start(ctx);
 	dsa_p = BN_CTX_get(ctx);
 	dsa_q = BN_CTX_get(ctx);
 	dsa_g = BN_CTX_get(ctx);
 	dsa_key = BN_CTX_get(ctx);
 	result = BN_CTX_get(ctx);
-	if(!dsa_p || !dsa_q || !dsa_g || !dsa_key || !result)
+	if(!result)
 		{
 		ENGINEerr(ENGINE_F_CSWIFT_DSA_SIGN,ENGINE_R_BN_CTX_FULL);
 		goto err;
@@ -672,13 +665,11 @@ static DSA_SIG *cswift_dsa_sign(const unsigned char *dgst, int dlen, DSA *dsa)
 err:
 	if(acquired)
 		release_context(hac);
-	if(dsa_p) ctx->tos--;
-	if(dsa_q) ctx->tos--;
-	if(dsa_g) ctx->tos--;
-	if(dsa_key) ctx->tos--;
-	if(result) ctx->tos--;
 	if(ctx)
+		{
+		BN_CTX_end(ctx);
 		BN_CTX_free(ctx);
+		}
 	return to_return;
 	}
 
@@ -708,12 +699,13 @@ static int cswift_dsa_verify(const unsigned char *dgst, int dgst_len,
 		}
 	acquired = 1;
 	/* Prepare the params */
+	BN_CTX_start(ctx);
 	dsa_p = BN_CTX_get(ctx);
 	dsa_q = BN_CTX_get(ctx);
 	dsa_g = BN_CTX_get(ctx);
 	dsa_key = BN_CTX_get(ctx);
 	argument = BN_CTX_get(ctx);
-	if(!dsa_p || !dsa_q || !dsa_g || !dsa_key || !argument)
+	if(!argument)
 		{
 		ENGINEerr(ENGINE_F_CSWIFT_DSA_VERIFY,ENGINE_R_BN_CTX_FULL);
 		goto err;
@@ -786,13 +778,11 @@ static int cswift_dsa_verify(const unsigned char *dgst, int dgst_len,
 err:
 	if(acquired)
 		release_context(hac);
-	if(dsa_p) ctx->tos--;
-	if(dsa_q) ctx->tos--;
-	if(dsa_g) ctx->tos--;
-	if(dsa_key) ctx->tos--;
-	if(argument) ctx->tos--;
 	if(ctx)
+		{
+		BN_CTX_end(ctx);
 		BN_CTX_free(ctx);
+		}
 	return to_return;
 	}