Initial support for DH_METHOD. Also added a DH lock. A few changes made to

DSA_METHOD to make it more consistent with RSA_METHOD.

3 files changed, 174 insertions, 9 deletions

diff --git a/crypto/dh/dh.h b/crypto/dh/dh.h
index 2cc3797a94..5d17a27a2a 100644
--- a/crypto/dh/dh.h
+++ b/crypto/dh/dh.h
@@ -68,10 +68,28 @@ extern "C" {
 #endif
 
 #include <openssl/bn.h>
+#include <openssl/crypto.h>
 	
 #define DH_FLAG_CACHE_MONT_P	0x01
 
-typedef struct dh_st
+typedef struct dh_st DH;
+
+typedef struct dh_method {
+	const char *name;
+	/* Methods here */
+	int (*generate_key)(DH *dh);
+	int (*compute_key)(unsigned char *key,BIGNUM *pub_key,DH *dh);
+	int (*bn_mod_exp)(DH *dh, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
+				const BIGNUM *m, BN_CTX *ctx,
+				BN_MONT_CTX *m_ctx); /* Can be null */
+
+	int (*init)(DH *dh);
+	int (*finish)(DH *dh);
+	int flags;
+	char *app_data;
+} DH_METHOD;
+
+struct dh_st
 	{
 	/* This first argument is used to pick up errors when
 	 * a DH is passed instead of a EVP_PKEY */
@@ -85,7 +103,17 @@ typedef struct dh_st
 
 	int flags;
 	char *method_mont_p;
-	} DH;
+	/* Place holders if we want to do X9.42 DH */
+	BIGNUM *q;
+	BIGNUM *j;
+	unsigned *seed;
+	int seedlen;
+	BIGNUM *counter;
+
+	int references;
+	CRYPTO_EX_DATA ex_data;
+	DH_METHOD *meth;
+	};
 
 #define DH_GENERATOR_2		2
 /* #define DH_GENERATOR_3	3 */
@@ -113,9 +141,20 @@ typedef struct dh_st
 		(unsigned char *)(x))
 #endif
 
+DH_METHOD *DH_OpenSSL(void);
+
+void DH_set_default_method(DH_METHOD *meth);
+DH_METHOD *DH_get_default_method(void);
+DH_METHOD *DH_set_method(DH *dh, DH_METHOD *meth);
+DH *DH_new_method(DH_METHOD *meth);
+
 DH *	DH_new(void);
 void	DH_free(DH *dh);
 int	DH_size(DH *dh);
+int DH_get_ex_new_index(long argl, char *argp, int (*new_func)(),
+	     int (*dup_func)(), void (*free_func)());
+int DH_set_ex_data(DH *d, int idx, char *arg);
+char *DH_get_ex_data(DH *d, int idx);
 DH *	DH_generate_parameters(int prime_len,int generator,
 		void (*callback)(int,int,void *),void *cb_arg);
 int	DH_check(DH *dh,int *codes);
diff --git a/crypto/dh/dh_key.c b/crypto/dh/dh_key.c
index cede53bfc1..4e6a0fc0ef 100644
--- a/crypto/dh/dh_key.c
+++ b/crypto/dh/dh_key.c
@@ -62,8 +62,42 @@
 #include <openssl/rand.h>
 #include <openssl/dh.h>
 
+static int generate_key(DH *dh);
+static int compute_key(unsigned char *key, BIGNUM *pub_key, DH *dh);
+static int dh_bn_mod_exp(DH *dh, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
+			const BIGNUM *m, BN_CTX *ctx,
+			BN_MONT_CTX *m_ctx);
+static int dh_init(DH *dh);
+static int dh_finish(DH *dh);
+
 int DH_generate_key(DH *dh)
 	{
+	return dh->meth->generate_key(dh);
+	}
+
+int DH_compute_key(unsigned char *key, BIGNUM *pub_key, DH *dh)
+	{
+	return dh->meth->compute_key(key, pub_key, dh);
+	}
+
+static DH_METHOD dh_ossl = {
+"OpenSSL DH Method",
+generate_key,
+compute_key,
+dh_bn_mod_exp,
+dh_init,
+dh_finish,
+0,
+NULL
+};
+
+DH_METHOD *DH_OpenSSL(void)
+{
+	return &dh_ossl;
+}
+
+static int generate_key(DH *dh)
+	{
 	int ok=0;
 	unsigned int i;
 	BN_CTX ctx;
@@ -103,7 +137,8 @@ int DH_generate_key(DH *dh)
 		}
 	mont=(BN_MONT_CTX *)dh->method_mont_p;
 
-	if (!BN_mod_exp_mont(pub_key,dh->g,priv_key,dh->p,&ctx,mont)) goto err;
+	if (!dh->meth->bn_mod_exp(dh, pub_key,dh->g,priv_key,dh->p,&ctx,mont))
+								goto err;
 		
 	dh->pub_key=pub_key;
 	dh->priv_key=priv_key;
@@ -118,7 +153,7 @@ err:
 	return(ok);
 	}
 
-int DH_compute_key(unsigned char *key, BIGNUM *pub_key, DH *dh)
+static int compute_key(unsigned char *key, BIGNUM *pub_key, DH *dh)
 	{
 	BN_CTX ctx;
 	BN_MONT_CTX *mont;
@@ -141,7 +176,7 @@ int DH_compute_key(unsigned char *key, BIGNUM *pub_key, DH *dh)
 		}
 
 	mont=(BN_MONT_CTX *)dh->method_mont_p;
-	if (!BN_mod_exp_mont(tmp,pub_key,dh->priv_key,dh->p,&ctx,mont))
+	if (!dh->meth->bn_mod_exp(dh, tmp,pub_key,dh->priv_key,dh->p,&ctx,mont))
 		{
 		DHerr(DH_F_DH_COMPUTE_KEY,ERR_R_BN_LIB);
 		goto err;
@@ -152,3 +187,23 @@ err:
 	BN_CTX_free(&ctx);
 	return(ret);
 	}
+
+static int dh_bn_mod_exp(DH *dh, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
+			const BIGNUM *m, BN_CTX *ctx,
+			BN_MONT_CTX *m_ctx)
+{
+	return BN_mod_exp_mont(r, a, p, m, ctx, m_ctx);
+}
+
+static int dh_init(DH *dh)
+{
+	dh->flags |= DH_FLAG_CACHE_MONT_P;
+	return(1);
+}
+
+static int dh_finish(DH *dh)
+{
+	if(dh->method_mont_p)
+		BN_MONT_CTX_free((BN_MONT_CTX *)dh->method_mont_p);
+	return(1);
+}
diff --git a/crypto/dh/dh_lib.c b/crypto/dh/dh_lib.c
index 61e0720e8a..ef622629f7 100644
--- a/crypto/dh/dh_lib.c
+++ b/crypto/dh/dh_lib.c
@@ -63,16 +63,49 @@
 
 const char *DH_version="Diffie-Hellman" OPENSSL_VERSION_PTEXT;
 
+static DH_METHOD *default_DH_method;
+static int dh_meth_num = 0;
+static STACK *dh_meth = NULL;
+
+void DH_set_default_method(DH_METHOD *meth)
+{
+	default_DH_method = meth;
+}
+
+DH_METHOD *DH_get_default_method(void)
+{
+	if(!default_DH_method) default_DH_method = DH_OpenSSL();
+	return default_DH_method;
+}
+
+DH_METHOD *DH_set_method(DH *dh, DH_METHOD *meth)
+{
+        DH_METHOD *mtmp;
+        mtmp = dh->meth;
+        if (mtmp->finish) mtmp->finish(dh);
+        dh->meth = meth;
+        if (meth->init) meth->init(dh);
+        return mtmp;
+}
+
 DH *DH_new(void)
+{
+	return DH_new_method(NULL);
+}
+
+DH *DH_new_method(DH_METHOD *meth)
 	{
 	DH *ret;
-
 	ret=(DH *)Malloc(sizeof(DH));
+
 	if (ret == NULL)
 		{
 		DHerr(DH_F_DH_NEW,ERR_R_MALLOC_FAILURE);
 		return(NULL);
 		}
+	if(!default_DH_method) default_DH_method = DH_OpenSSL();
+	if(meth) ret->meth = meth;
+	else ret->meth = default_DH_method;
 	ret->pad=0;
 	ret->version=0;
 	ret->p=NULL;
@@ -80,23 +113,61 @@ DH *DH_new(void)
 	ret->length=0;
 	ret->pub_key=NULL;
 	ret->priv_key=NULL;
-	ret->flags=DH_FLAG_CACHE_MONT_P;
 	ret->method_mont_p=NULL;
+	ret->references = 1;
+	ret->flags=ret->meth->flags;
+	if ((ret->meth->init != NULL) && !ret->meth->init(ret))
+		{
+		Free(ret);
+		ret=NULL;
+		}
+	else
+		CRYPTO_new_ex_data(dh_meth,(char *)ret,&ret->ex_data);
 	return(ret);
 	}
 
 void DH_free(DH *r)
 	{
+	int i;
 	if(r == NULL) return;
+	i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH);
+#ifdef REF_PRINT
+	REF_PRINT("DH",r);
+#endif
+	if (i > 0) return;
+#ifdef REF_CHECK
+	if (i < 0)
+		{
+		fprintf(stderr,"DH_free, bad reference count\n");
+		abort();
+	}
+#endif
+
 	if (r->p != NULL) BN_clear_free(r->p);
 	if (r->g != NULL) BN_clear_free(r->g);
 	if (r->pub_key != NULL) BN_clear_free(r->pub_key);
 	if (r->priv_key != NULL) BN_clear_free(r->priv_key);
-	if (r->method_mont_p != NULL)
-		BN_MONT_CTX_free((BN_MONT_CTX *)r->method_mont_p);
 	Free(r);
 	}
 
+int DH_get_ex_new_index(long argl, char *argp, int (*new_func)(),
+	     int (*dup_func)(), void (*free_func)())
+        {
+	dh_meth_num++;
+	return(CRYPTO_get_ex_new_index(dh_meth_num-1,
+		&dh_meth,argl,argp,new_func,dup_func,free_func));
+        }
+
+int DH_set_ex_data(DH *d, int idx, char *arg)
+	{
+	return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
+	}
+
+char *DH_get_ex_data(DH *d, int idx)
+	{
+	return(CRYPTO_get_ex_data(&d->ex_data,idx));
+	}
+
 int DH_size(DH *dh)
 	{
 	return(BN_num_bytes(dh->p));