New function DSA_dup_DH, and fixes for bugs that were found

while implementing and using it.

3 files changed, 80 insertions, 28 deletions

diff --git a/crypto/dsa/Makefile.ssl b/crypto/dsa/Makefile.ssl
index 1a380966cc..6d80ce77be 100644
--- a/crypto/dsa/Makefile.ssl
+++ b/crypto/dsa/Makefile.ssl
@@ -81,47 +81,53 @@ clean:
 dsa_asn1.o: ../../include/openssl/asn1.h ../../include/openssl/asn1_mac.h
 dsa_asn1.o: ../../include/openssl/bio.h ../../include/openssl/bn.h
 dsa_asn1.o: ../../include/openssl/buffer.h ../../include/openssl/crypto.h
-dsa_asn1.o: ../../include/openssl/dsa.h ../../include/openssl/e_os.h
-dsa_asn1.o: ../../include/openssl/e_os2.h ../../include/openssl/err.h
-dsa_asn1.o: ../../include/openssl/opensslconf.h
+dsa_asn1.o: ../../include/openssl/dh.h ../../include/openssl/dsa.h
+dsa_asn1.o: ../../include/openssl/e_os.h ../../include/openssl/e_os2.h
+dsa_asn1.o: ../../include/openssl/err.h ../../include/openssl/opensslconf.h
 dsa_asn1.o: ../../include/openssl/opensslv.h ../../include/openssl/safestack.h
 dsa_asn1.o: ../../include/openssl/stack.h ../cryptlib.h
-dsa_err.o: ../../include/openssl/bn.h ../../include/openssl/dsa.h
-dsa_err.o: ../../include/openssl/err.h ../../include/openssl/opensslconf.h
+dsa_err.o: ../../include/openssl/bn.h ../../include/openssl/dh.h
+dsa_err.o: ../../include/openssl/dsa.h ../../include/openssl/err.h
+dsa_err.o: ../../include/openssl/opensslconf.h
 dsa_gen.o: ../../include/openssl/bio.h ../../include/openssl/bn.h
 dsa_gen.o: ../../include/openssl/buffer.h ../../include/openssl/crypto.h
-dsa_gen.o: ../../include/openssl/dsa.h ../../include/openssl/e_os.h
-dsa_gen.o: ../../include/openssl/e_os2.h ../../include/openssl/err.h
-dsa_gen.o: ../../include/openssl/opensslconf.h ../../include/openssl/opensslv.h
-dsa_gen.o: ../../include/openssl/rand.h ../../include/openssl/sha.h
-dsa_gen.o: ../../include/openssl/stack.h ../cryptlib.h
+dsa_gen.o: ../../include/openssl/dh.h ../../include/openssl/dsa.h
+dsa_gen.o: ../../include/openssl/e_os.h ../../include/openssl/e_os2.h
+dsa_gen.o: ../../include/openssl/err.h ../../include/openssl/opensslconf.h
+dsa_gen.o: ../../include/openssl/opensslv.h ../../include/openssl/rand.h
+dsa_gen.o: ../../include/openssl/sha.h ../../include/openssl/stack.h
+dsa_gen.o: ../cryptlib.h
 dsa_key.o: ../../include/openssl/bio.h ../../include/openssl/bn.h
 dsa_key.o: ../../include/openssl/buffer.h ../../include/openssl/crypto.h
-dsa_key.o: ../../include/openssl/dsa.h ../../include/openssl/e_os.h
-dsa_key.o: ../../include/openssl/e_os2.h ../../include/openssl/err.h
-dsa_key.o: ../../include/openssl/opensslconf.h ../../include/openssl/opensslv.h
-dsa_key.o: ../../include/openssl/rand.h ../../include/openssl/sha.h
-dsa_key.o: ../../include/openssl/stack.h ../cryptlib.h
+dsa_key.o: ../../include/openssl/dh.h ../../include/openssl/dsa.h
+dsa_key.o: ../../include/openssl/e_os.h ../../include/openssl/e_os2.h
+dsa_key.o: ../../include/openssl/err.h ../../include/openssl/opensslconf.h
+dsa_key.o: ../../include/openssl/opensslv.h ../../include/openssl/rand.h
+dsa_key.o: ../../include/openssl/sha.h ../../include/openssl/stack.h
+dsa_key.o: ../cryptlib.h
 dsa_lib.o: ../../include/openssl/asn1.h ../../include/openssl/bio.h
 dsa_lib.o: ../../include/openssl/bn.h ../../include/openssl/buffer.h
-dsa_lib.o: ../../include/openssl/crypto.h ../../include/openssl/dsa.h
-dsa_lib.o: ../../include/openssl/e_os.h ../../include/openssl/e_os2.h
-dsa_lib.o: ../../include/openssl/err.h ../../include/openssl/opensslconf.h
-dsa_lib.o: ../../include/openssl/opensslv.h ../../include/openssl/safestack.h
-dsa_lib.o: ../../include/openssl/stack.h ../cryptlib.h
+dsa_lib.o: ../../include/openssl/crypto.h ../../include/openssl/dh.h
+dsa_lib.o: ../../include/openssl/dsa.h ../../include/openssl/e_os.h
+dsa_lib.o: ../../include/openssl/e_os2.h ../../include/openssl/err.h
+dsa_lib.o: ../../include/openssl/opensslconf.h ../../include/openssl/opensslv.h
+dsa_lib.o: ../../include/openssl/safestack.h ../../include/openssl/stack.h
+dsa_lib.o: ../cryptlib.h
 dsa_sign.o: ../../include/openssl/asn1.h ../../include/openssl/bio.h
 dsa_sign.o: ../../include/openssl/bn.h ../../include/openssl/buffer.h
-dsa_sign.o: ../../include/openssl/crypto.h ../../include/openssl/dsa.h
-dsa_sign.o: ../../include/openssl/e_os.h ../../include/openssl/e_os2.h
-dsa_sign.o: ../../include/openssl/err.h ../../include/openssl/opensslconf.h
+dsa_sign.o: ../../include/openssl/crypto.h ../../include/openssl/dh.h
+dsa_sign.o: ../../include/openssl/dsa.h ../../include/openssl/e_os.h
+dsa_sign.o: ../../include/openssl/e_os2.h ../../include/openssl/err.h
+dsa_sign.o: ../../include/openssl/opensslconf.h
 dsa_sign.o: ../../include/openssl/opensslv.h ../../include/openssl/rand.h
 dsa_sign.o: ../../include/openssl/safestack.h ../../include/openssl/stack.h
 dsa_sign.o: ../cryptlib.h
 dsa_vrf.o: ../../include/openssl/asn1.h ../../include/openssl/asn1_mac.h
 dsa_vrf.o: ../../include/openssl/bio.h ../../include/openssl/bn.h
 dsa_vrf.o: ../../include/openssl/buffer.h ../../include/openssl/crypto.h
-dsa_vrf.o: ../../include/openssl/dsa.h ../../include/openssl/e_os.h
-dsa_vrf.o: ../../include/openssl/e_os2.h ../../include/openssl/err.h
-dsa_vrf.o: ../../include/openssl/opensslconf.h ../../include/openssl/opensslv.h
-dsa_vrf.o: ../../include/openssl/rand.h ../../include/openssl/safestack.h
-dsa_vrf.o: ../../include/openssl/stack.h ../cryptlib.h
+dsa_vrf.o: ../../include/openssl/dh.h ../../include/openssl/dsa.h
+dsa_vrf.o: ../../include/openssl/e_os.h ../../include/openssl/e_os2.h
+dsa_vrf.o: ../../include/openssl/err.h ../../include/openssl/opensslconf.h
+dsa_vrf.o: ../../include/openssl/opensslv.h ../../include/openssl/rand.h
+dsa_vrf.o: ../../include/openssl/safestack.h ../../include/openssl/stack.h
+dsa_vrf.o: ../cryptlib.h
diff --git a/crypto/dsa/dsa.h b/crypto/dsa/dsa.h
index d9ff1933ee..20b3f8d90a 100644
--- a/crypto/dsa/dsa.h
+++ b/crypto/dsa/dsa.h
@@ -74,6 +74,9 @@ extern "C" {
 #endif
 
 #include <openssl/bn.h>
+#ifndef NO_DH
+# include <openssl/dh.h>
+#endif
 
 #define DSA_FLAG_CACHE_MONT_P	0x01
 
@@ -162,6 +165,12 @@ int	DSA_print_fp(FILE *bp, DSA *x, int off);
 
 int DSA_is_prime(BIGNUM *q,void (*callback)(),char *cb_arg);
 
+#ifndef NO_DH
+/* Convert DSA structure (key or just parameters) into DH structure
+ * (be careful to avoid small subgroup attacks when using this!) */
+DH *DSA_dup_DH(DSA *r);
+#endif
+
 /* BEGIN ERROR CODES */
 /* The following lines are auto generated by the script mkerr.pl. Any changes
  * made after this point may be overwritten when the script is next run.
diff --git a/crypto/dsa/dsa_lib.c b/crypto/dsa/dsa_lib.c
index 8923fb45f4..a5f0182101 100644
--- a/crypto/dsa/dsa_lib.c
+++ b/crypto/dsa/dsa_lib.c
@@ -145,3 +145,40 @@ int DSA_size(DSA *r)
 	return(ret);
 	}
 
+#ifndef NO_DH
+DH *DSA_dup_DH(DSA *r)
+	{
+	/* DSA has p, q, g, optional pub_key, optional priv_key.
+	 * DH has p, optional length, g, optional pub_key, optional priv_key.
+	 */ 
+
+	DH *ret;
+
+	if (r == NULL)
+		goto err;
+	ret = DH_new();
+	if (ret == NULL)
+		goto err;
+	if (r->p != NULL) 
+		if ((ret->p = BN_dup(r->p)) == NULL)
+			goto err;
+	if (r->q != NULL)
+		ret->length = BN_num_bits(r->q);
+	if (r->g != NULL)
+		if ((ret->g = BN_dup(r->g)) == NULL)
+			goto err;
+	if (r->pub_key != NULL)
+		if ((ret->pub_key = BN_dup(r->pub_key)) == NULL)
+			goto err;
+	if (r->priv_key != NULL)
+		if ((ret->priv_key = BN_dup(r->priv_key)) == NULL)
+			goto err;
+
+	return ret;
+
+ err:
+	if (ret != NULL)
+		DH_free(ret);
+	return NULL;
+	}
+#endif