- Add Fortuna PRNG to pgcrypto.

- 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

contrib/pgcrypto/Makefile

 #
-# $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)
 

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;
+}
+

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;
+}
+

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);
 

contrib/pgcrypto/random.c

 /*
  * random.c
- *		Random functions.
+ *		Acquire randomness from system.  For seeding RNG.
  *
  * Copyright (c) 2001 Marko Kreen
  * All rights reserved.
@@ -26,7 +26,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- * $PostgreSQL: pgsql/contrib/pgcrypto/random.c,v 1.10 2005/03/21 05:22:14 neilc Exp $
+ * $PostgreSQL: pgsql/contrib/pgcrypto/random.c,v 1.11 2005/07/10 03:55:28 momjian Exp $
  */
 
 
@@ -34,8 +34,20 @@
 
 #include "px.h"
 
+/* how many bytes to ask from system random provider */
+#define RND_BYTES  32
 
-#if defined(RAND_DEV)
+/*
+ * Try to read from /dev/urandom or /dev/random on these OS'es.
+ *
+ * The list can be pretty liberal, as the device not existing
+ * is expected event.
+ */
+#if defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__) \
+	|| defined(__NetBSD__) || defined(__DragonFly__) \
+	|| defined(__darwin__) || defined(__SOLARIS__)
+
+#define TRY_DEV_RANDOM
 
 #include <errno.h>
 #include <fcntl.h>
@@ -64,94 +76,169 @@ safe_read(int fd, void *buf, size_t count)
 	return done;
 }
 
-int
-px_get_random_bytes(uint8 *dst, unsigned count)
+static uint8 *
+try_dev_random(uint8 *dst)
 {
 	int			fd;
 	int			res;
 
-	fd = open(RAND_DEV, O_RDONLY);
+	fd = open("/dev/urandom", O_RDONLY);
 	if (fd == -1)
-		return PXE_DEV_READ_ERROR;
-	res = safe_read(fd, dst, count);
+	{
+		fd = open("/dev/random", O_RDONLY);
+		if (fd == -1)
+			return dst;
+	}
+	res = safe_read(fd, dst, RND_BYTES);
 	close(fd);
-	return res;
-}
-
-int
-px_get_pseudo_random_bytes(uint8 *dst, unsigned count)
-{
-	return px_get_random_bytes(dst, count);
-}
-
-#elif defined(RAND_SILLY)
-
-int
-px_get_pseudo_random_bytes(uint8 *dst, unsigned count)
-{
-	int			i;
-
-	for (i = 0; i < count; i++)
-		*dst++ = random();
-	return i;
+	if (res > 0)
+		dst += res;
+	return dst;
 }
 
-int
-px_get_random_bytes(uint8 *dst, unsigned count)
-{
-	return PXE_NO_RANDOM;
-}
+#endif
 
-#elif defined(RAND_OPENSSL)
+/*
+ * Try to find randomness on Windows
+ */
+#ifdef WIN32
 
-#include <openssl/evp.h>
-#include <openssl/blowfish.h>
-#include <openssl/rand.h>
-#include <openssl/err.h>
+#define TRY_WIN32_GENRAND
+#define TRY_WIN32_PERFC
 
-static int	openssl_random_init = 0;
+#define _WIN32_WINNT 0x0400
+#include <windows.h>
+#include <wincrypt.h>
 
 /*
- * OpenSSL random should re-feeded occasionally. From /dev/urandom
- * preferably.
+ * this function is from libtomcrypt
+ * 
+ * try to use Microsoft crypto API
  */
-static void init_openssl()
+static uint8 * try_win32_genrand(uint8 *dst)
 {
-	if (RAND_get_rand_method() == NULL)
-		RAND_set_rand_method(RAND_SSLeay());
-	openssl_random_init = 1;
+	int res;
+	HCRYPTPROV h = 0;
+
+	res = CryptAcquireContext(&h, NULL, MS_DEF_PROV, PROV_RSA_FULL,
+				(CRYPT_VERIFYCONTEXT | CRYPT_MACHINE_KEYSET));
+	if (!res)
+		res = CryptAcquireContext(&h, NULL, MS_DEF_PROV, PROV_RSA_FULL,
+				CRYPT_VERIFYCONTEXT | CRYPT_MACHINE_KEYSET | CRYPT_NEWKEYSET);
+	if (!res)
+		return dst;
+	
+	res = CryptGenRandom(h, NUM_BYTES, dst);
+	if (res == TRUE)
+		dst += len;
+
+	CryptReleaseContext(h, 0);
+	return dst;
 }
 
-int
-px_get_random_bytes(uint8 *dst, unsigned count)
+static uint8 * try_win32_perfc(uint8 *dst)
 {
 	int res;
+	LARGE_INTEGER time;
 
-	if (!openssl_random_init)
-		init_openssl();
-
-	res = RAND_bytes(dst, count);
-	if (res == 1)
-		return count;
+	res = QueryPerformanceCounter(&time);
+	if (!res)
+		return dst;
 
-	return PXE_OSSL_RAND_ERROR;
+	memcpy(dst, &time, sizeof(time));
+	return dst + sizeof(time);
 }
 
-int
-px_get_pseudo_random_bytes(uint8 *dst, unsigned count)
+#endif /* WIN32 */
+
+
+/*
+ * If we are not on Windows, then hopefully we are
+ * on a unix-like system.  Use the usual suspects
+ * for randomness.
+ */
+#ifndef WIN32
+
+#define TRY_UNIXSTD
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <time.h>
+#include <unistd.h>
+
+/*
+ * Everything here is predictible, only needs some patience.
+ *
+ * But there is a chance that the system-specific functions
+ * did not work.  So keep faith and try to slow the attacker down.
+ */
+static uint8 *
+try_unix_std(uint8 *dst)
 {
+	pid_t pid;
+	int x;
+	PX_MD *md;
+	struct timeval tv;
 	int res;
 
-	if (!openssl_random_init)
-		init_openssl();
-
-	res = RAND_pseudo_bytes(dst, count);
-	if (res == 0 || res == 1)
-		return count;
+	/* process id */
+	pid = getpid();
+	memcpy(dst, (uint8*)&pid, sizeof(pid));
+	dst += sizeof(pid);
+
+	/* time */
+	gettimeofday(&tv, NULL);
+	memcpy(dst, (uint8*)&tv, sizeof(tv));
+	dst += sizeof(tv);
+
+	/* pointless, but should not hurt */
+	x = random();
+	memcpy(dst, (uint8*)&x, sizeof(x));
+	dst += sizeof(x);
+
+	/* let's be desperate */
+	res = px_find_digest("sha1", &md);
+	if (res >= 0) {
+		uint8 *ptr;
+		uint8 stack[8192];
+		int alloc = 32*1024;
+
+		px_md_update(md, stack, sizeof(stack));
+		ptr = px_alloc(alloc);
+		px_md_update(md, ptr, alloc);
+		px_free(ptr);
+
+		px_md_finish(md, dst);
+		px_md_free(md);
+
+		dst += 20;
+	}
 
-	return PXE_OSSL_RAND_ERROR;
+	return dst;
 }
 
-#else
-#error "Invalid random source"
 #endif
+
+/*
+ * try to extract some randomness for initial seeding
+ *
+ * dst should have room for 1024 bytes.
+ */
+unsigned px_acquire_system_randomness(uint8 *dst)
+{
+	uint8 *p = dst;
+#ifdef TRY_DEV_RANDOM
+	p = try_dev_random(p);
+#endif
+#ifdef TRY_WIN32_GENRAND
+	p = try_win32_genrand(p);
+#endif
+#ifdef TRY_WIN32_PERFC
+	p = try_win32_perfc(p);
+#endif
+#ifdef TRY_UNIXSTD
+	p = try_unix_std(p);
+#endif
+	return p - dst;
+}
+