This is a first-cut at improving the callback mechanisms used in

key-generation and prime-checking functions. Rather than explicitly passing
callback functions and caller-defined context data for the callbacks, a new
structure BN_GENCB is defined that encapsulates this; a pointer to the
structure is passed to all such functions instead.

This wrapper structure allows the encapsulation of "old" and "new" style
callbacks - "new" callbacks return a boolean result on the understanding
that returning FALSE should terminate keygen/primality processing.  The
BN_GENCB abstraction will allow future callback modifications without
needing to break binary compatibility nor change the API function
prototypes. The new API functions have been given names ending in "_ex" and
the old functions are implemented as wrappers to the new ones.  The
OPENSSL_NO_DEPRECATED symbol has been introduced so that, if defined,
declaration of the older functions will be skipped. NB: Some
openssl-internal code will stick with the older callbacks for now, so
appropriate "#undef" logic will be put in place - this is in case the user
is *building* openssl (rather than *including* its headers) with this
symbol defined.

There is another change in the new _ex functions; the key-generation
functions do not return key structures but operate on structures passed by
the caller, the return value is a boolean. This will allow for a smoother
transition to having key-generation as "virtual function" in the various
***_METHOD tables.

6 files changed, 113 insertions, 21 deletions

diff --git a/crypto/dh/Makefile.ssl b/crypto/dh/Makefile.ssl
index e1cb248db5..c1ed5ad920 100644
--- a/crypto/dh/Makefile.ssl
+++ b/crypto/dh/Makefile.ssl
@@ -23,8 +23,8 @@ TEST= dhtest.c
 APPS=
 
 LIB=$(TOP)/libcrypto.a
-LIBSRC= dh_asn1.c dh_gen.c dh_key.c dh_lib.c dh_check.c dh_err.c
-LIBOBJ= dh_asn1.o dh_gen.o dh_key.o dh_lib.o dh_check.o dh_err.o
+LIBSRC= dh_asn1.c dh_gen.c dh_key.c dh_lib.c dh_check.c dh_err.c dh_depr.c
+LIBOBJ= dh_asn1.o dh_gen.o dh_key.o dh_lib.o dh_check.o dh_err.o dh_depr.o
 
 SRC= $(LIBSRC)
 
diff --git a/crypto/dh/dh.h b/crypto/dh/dh.h
index 05851f8429..cab9b1493d 100644
--- a/crypto/dh/dh.h
+++ b/crypto/dh/dh.h
@@ -165,8 +165,16 @@ int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
 int DH_set_ex_data(DH *d, int idx, void *arg);
 void *DH_get_ex_data(DH *d, int idx);
+
+/* Deprecated version */
+#ifndef OPENSSL_NO_DEPRECATED
 DH *	DH_generate_parameters(int prime_len,int generator,
 		void (*callback)(int,int,void *),void *cb_arg);
+#endif /* !defined(OPENSSL_NO_DEPRECATED) */
+
+/* New version */
+int	DH_generate_parameters_ex(DH *dh, int prime_len,int generator, BN_GENCB *cb);
+
 int	DH_check(const DH *dh,int *codes);
 int	DH_generate_key(DH *dh);
 int	DH_compute_key(unsigned char *key,const BIGNUM *pub_key,DH *dh);
diff --git a/crypto/dh/dh_check.c b/crypto/dh/dh_check.c
index f0373f7d68..bfc9c3ad76 100644
--- a/crypto/dh/dh_check.c
+++ b/crypto/dh/dh_check.c
@@ -104,12 +104,12 @@ int DH_check(const DH *dh, int *ret)
 	else
 		*ret|=DH_UNABLE_TO_CHECK_GENERATOR;
 
-	if (!BN_is_prime(dh->p,BN_prime_checks,NULL,ctx,NULL))
+	if (!BN_is_prime_ex(dh->p,BN_prime_checks,ctx,NULL))
 		*ret|=DH_CHECK_P_NOT_PRIME;
 	else
 		{
 		if (!BN_rshift1(q,dh->p)) goto err;
-		if (!BN_is_prime(q,BN_prime_checks,NULL,ctx,NULL))
+		if (!BN_is_prime_ex(q,BN_prime_checks,ctx,NULL))
 			*ret|=DH_CHECK_P_NOT_SAFE_PRIME;
 		}
 	ok=1;
diff --git a/crypto/dh/dh_depr.c b/crypto/dh/dh_depr.c
new file mode 100644
index 0000000000..8a909b1959
--- /dev/null
+++ b/crypto/dh/dh_depr.c
@@ -0,0 +1,81 @@
+/* crypto/dh/dh_depr.c */
+/* ====================================================================
+ * Copyright (c) 1998-2002 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
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer. 
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
+
+/* This file contains deprecated functions as wrappers to the new ones */
+
+#include <stdio.h>
+#include "cryptlib.h"
+#include <openssl/bn.h>
+#include <openssl/dh.h>
+
+DH *DH_generate_parameters(int prime_len, int generator,
+	     void (*callback)(int,int,void *), void *cb_arg)
+	{
+	BN_GENCB cb;
+	DH *ret=NULL;
+
+	if((ret=DH_new()) == NULL)
+		return NULL;
+
+	cb.ver = 1;
+	cb.arg = cb_arg;
+	cb.cb_1 = callback;
+
+	if(DH_generate_parameters_ex(ret, prime_len, generator, &cb))
+		return ret;
+	DH_free(ret);
+	return NULL;
+	}
diff --git a/crypto/dh/dh_gen.c b/crypto/dh/dh_gen.c
index 06f78b35ab..a929a0f064 100644
--- a/crypto/dh/dh_gen.c
+++ b/crypto/dh/dh_gen.c
@@ -56,6 +56,11 @@
  * [including the GNU Public Licence.]
  */
 
+/* NB: These functions have been upgraded - the previous prototypes are in
+ * dh_depr.c as wrappers to these ones.
+ *  - Geoff
+ */
+
 #include <stdio.h>
 #include "cryptlib.h"
 #include <openssl/bn.h>
@@ -86,22 +91,22 @@
  * It's just as OK (and in some sense better) to use a generator of the
  * order-q subgroup.
  */
-DH *DH_generate_parameters(int prime_len, int generator,
-	     void (*callback)(int,int,void *), void *cb_arg)
+int DH_generate_parameters_ex(DH *ret, int prime_len, int generator, BN_GENCB *cb)
 	{
-	BIGNUM *p=NULL,*t1,*t2;
-	DH *ret=NULL;
+	BIGNUM *t1,*t2;
 	int g,ok= -1;
 	BN_CTX *ctx=NULL;
 
-	ret=DH_new();
-	if (ret == NULL) goto err;
 	ctx=BN_CTX_new();
 	if (ctx == NULL) goto err;
 	BN_CTX_start(ctx);
 	t1 = BN_CTX_get(ctx);
 	t2 = BN_CTX_get(ctx);
 	if (t1 == NULL || t2 == NULL) goto err;
+
+	/* Make sure 'ret' has the necessary elements */
+	if(!ret->p && ((ret->p = BN_new()) == NULL)) goto err;
+	if(!ret->g && ((ret->g = BN_new()) == NULL)) goto err;
 	
 	if (generator <= 1)
 		{
@@ -141,11 +146,8 @@ DH *DH_generate_parameters(int prime_len, int generator,
 		g=generator;
 		}
 	
-	p=BN_generate_prime(NULL,prime_len,1,t1,t2,callback,cb_arg);
-	if (p == NULL) goto err;
-	if (callback != NULL) callback(3,0,cb_arg);
-	ret->p=p;
-	ret->g=BN_new();
+	if(!BN_generate_prime_ex(ret->p,prime_len,1,t1,t2,cb)) goto err;
+	if(!BN_GENCB_call(cb, 3, 0)) goto err;
 	if (!BN_set_word(ret->g,g)) goto err;
 	ok=1;
 err:
@@ -160,10 +162,5 @@ err:
 		BN_CTX_end(ctx);
 		BN_CTX_free(ctx);
 		}
-	if (!ok && (ret != NULL))
-		{
-		DH_free(ret);
-		ret=NULL;
-		}
-	return(ret);
+	return ok;
 	}
diff --git a/crypto/dh/dhtest.c b/crypto/dh/dhtest.c
index 27237741da..33a49f2d7d 100644
--- a/crypto/dh/dhtest.c
+++ b/crypto/dh/dhtest.c
@@ -56,6 +56,12 @@
  * [including the GNU Public Licence.]
  */
 
+/* Until the key-gen callbacks are modified to use newer prototypes, we allow
+ * deprecated functions for openssl-internal code */
+#ifdef OPENSSL_NO_DEPRECATED
+#undef OPENSSL_NO_DEPRECATED
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>