- Add Fortuna PRNG to pgcrypto.

bmomjian · bmomjian · commit 4fcf8b11ff45 · 2005-07-10T03:55:28.000Z
- Move openssl random provider to openssl.c and builtin provider
  to internal.c
- Make px_random_bytes use Fortuna, instead of giving error.
- Retarget random.c to aquiring system randomness, for initial seeding
  of Fortuna.  There is ATM 2 functions for Windows,
  reader from /dev/urandom and the regular time()/getpid() silliness.

Marko Kreen
diff --git a/contrib/pgcrypto/Makefile b/contrib/pgcrypto/Makefile
@@ -1,25 +1,21 @@
 #
-# $PostgreSQL: pgsql/contrib/pgcrypto/Makefile,v 1.18 2005/07/10 03:52:56 momjian Exp $
+# $PostgreSQL: pgsql/contrib/pgcrypto/Makefile,v 1.19 2005/07/10 03:55:28 momjian Exp $
 #
 
-# if you don't have OpenSSL, you can use libc random() or /dev/urandom
-INT_CFLAGS = -DRAND_SILLY
-#INT_CFLAGS = -DRAND_DEV=\"/dev/urandom\"
-
-INT_SRCS = md5.c sha1.c sha2.c internal.c blf.c rijndael.c
+INT_SRCS = md5.c sha1.c sha2.c internal.c blf.c rijndael.c \
+		fortuna.c random.c
 INT_TESTS = sha2
 
-OSSL_CFLAGS = -DRAND_OPENSSL
 OSSL_SRCS = openssl.c
 OSSL_TESTS = des 3des cast5
 
 CF_SRCS = $(if $(subst no,,$(with_openssl)), $(OSSL_SRCS), $(INT_SRCS))
 CF_TESTS = $(if $(subst no,,$(with_openssl)), $(OSSL_TESTS), $(INT_TESTS))
-CF_CFLAGS = $(if $(subst no,,$(with_openssl)), $(OSSL_CFLAGS), $(INT_CFLAGS))
+CF_CFLAGS =
 
 PG_CPPFLAGS	= $(CF_CFLAGS)
 
-SRCS		= pgcrypto.c px.c px-hmac.c px-crypt.c misc.c random.c \
+SRCS		= pgcrypto.c px.c px-hmac.c px-crypt.c misc.c \
 		crypt-gensalt.c crypt-blowfish.c crypt-des.c \
 		crypt-md5.c $(CF_SRCS)
 
diff --git a/contrib/pgcrypto/internal.c b/contrib/pgcrypto/internal.c
@@ -26,11 +26,12 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $PostgreSQL: pgsql/contrib/pgcrypto/internal.c,v 1.17 2005/07/10 03:52:56 momjian Exp $
+ * $PostgreSQL: pgsql/contrib/pgcrypto/internal.c,v 1.18 2005/07/10 03:55:28 momjian Exp $
  */
 
 
 #include <postgres.h>
+#include <time.h>
 
 #include "px.h"
 
@@ -39,6 +40,13 @@
 #include "sha2.h"
 #include "blf.h"
 #include "rijndael.h"
+#include "fortuna.h"
+
+/*
+ * How often to try to acquire system entropy.  (In seconds)
+ */
+#define SYSTEM_RESEED_FREQ	(3*60*60)
+
 
 #ifndef MD5_DIGEST_LENGTH
 #define MD5_DIGEST_LENGTH 16
@@ -784,3 +792,58 @@ px_find_cipher(const char *name, PX_Cipher ** res)
 	*res = c;
 	return 0;
 }
+
+/*
+ * Randomness provider
+ */
+
+/*
+ * Use libc for all 'public' bytes.
+ *
+ * That way we don't expose bytes from Fortuna
+ * to the public, in case it has some bugs.
+ */
+int
+px_get_pseudo_random_bytes(uint8 *dst, unsigned count)
+{
+	int         i;
+
+	for (i = 0; i < count; i++)
+		*dst++ = random();
+	return i;
+}
+
+static time_t seed_time = 0;
+static void system_reseed()
+{
+	uint8 buf[1024];
+	int n;
+	time_t t;
+
+	t = time(NULL);
+	if (seed_time && (t - seed_time) < SYSTEM_RESEED_FREQ)
+		return;
+
+	n = px_acquire_system_randomness(buf);
+	if (n > 0)
+		fortuna_add_entropy(SYSTEM_ENTROPY, buf, n);
+
+	seed_time = t;
+}
+
+int
+px_get_random_bytes(uint8 *dst, unsigned count)
+{
+	system_reseed();
+	fortuna_get_bytes(count, dst);
+	return 0;
+}
+
+int
+px_add_entropy(const uint8 *data, unsigned count)
+{
+	system_reseed();
+	fortuna_add_entropy(USER_ENTROPY, data, count);
+	return 0;
+}
+
diff --git a/contrib/pgcrypto/openssl.c b/contrib/pgcrypto/openssl.c
@@ -26,7 +26,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $PostgreSQL: pgsql/contrib/pgcrypto/openssl.c,v 1.20 2005/07/05 18:15:36 tgl Exp $
+ * $PostgreSQL: pgsql/contrib/pgcrypto/openssl.c,v 1.21 2005/07/10 03:55:28 momjian Exp $
  */
 
 #include <postgres.h>
@@ -37,6 +37,9 @@
 #include <openssl/blowfish.h>
 #include <openssl/cast.h>
 #include <openssl/des.h>
+#include <openssl/rand.h>
+#include <openssl/err.h>
+
 
 /*
  * Does OpenSSL support AES? 
@@ -759,3 +762,58 @@ px_find_cipher(const char *name, PX_Cipher ** res)
 	*res = c;
 	return 0;
 }
+
+
+static int	openssl_random_init = 0;
+
+/*
+ * OpenSSL random should re-feeded occasionally. From /dev/urandom
+ * preferably.
+ */
+static void init_openssl_rand()
+{
+	if (RAND_get_rand_method() == NULL)
+		RAND_set_rand_method(RAND_SSLeay());
+	openssl_random_init = 1;
+}
+
+int
+px_get_random_bytes(uint8 *dst, unsigned count)
+{
+	int			res;
+
+	if (!openssl_random_init)
+		init_openssl_rand();
+
+	res = RAND_bytes(dst, count);
+	if (res == 1)
+		return count;
+
+	return PXE_OSSL_RAND_ERROR;
+}
+
+int
+px_get_pseudo_random_bytes(uint8 *dst, unsigned count)
+{
+	int			res;
+
+	if (!openssl_random_init)
+		init_openssl_rand();
+
+	res = RAND_pseudo_bytes(dst, count);
+	if (res == 0 || res == 1)
+		return count;
+
+	return PXE_OSSL_RAND_ERROR;
+}
+
+int
+px_add_entropy(const uint8 *data, unsigned count)
+{
+	/*
+	 * estimate 0 bits
+	 */
+	RAND_add(data, count, 0);
+	return 0;
+}
+
diff --git a/contrib/pgcrypto/px.h b/contrib/pgcrypto/px.h
@@ -26,7 +26,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $PostgreSQL: pgsql/contrib/pgcrypto/px.h,v 1.12 2005/03/21 05:22:14 neilc Exp $
+ * $PostgreSQL: pgsql/contrib/pgcrypto/px.h,v 1.13 2005/07/10 03:55:28 momjian Exp $
  */
 
 #ifndef __PX_H
@@ -170,6 +170,9 @@ int			px_find_combo(const char *name, PX_Combo ** res);
 
 int			px_get_random_bytes(uint8 *dst, unsigned count);
 int			px_get_pseudo_random_bytes(uint8 *dst, unsigned count);
+int			px_add_entropy(const uint8 *data, unsigned count);
+
+unsigned	px_acquire_system_randomness(uint8 *dst);
 
 const char *px_strerror(int err);
 
diff --git a/contrib/pgcrypto/random.c b/contrib/pgcrypto/random.c
