From 76594cba9a1e910bb36160d96fc3872349341799 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Ond=C5=99ej=20Sur=C3=BD?= <ondrej@sury.org>

Date: Wed, 25 Apr 2018 14:04:31 +0200

Subject: [PATCH] Replace isc_safe routines with their OpenSSL counter parts

(cherry picked from commit 66ba2fdad583d962a1f4971c85d58381f0849e4d)

Remove isc_safe_memcompare, it's not needed anywhere and can't be replaced with CRYPTO_memcmp()

(cherry picked from commit b105ccee68ccc3c18e6ea530063b3c8e5a42571c)

Fix the isc_safe_memwipe() usage with (NULL, >0)

(cherry picked from commit 083461d3329ff6f2410745848a926090586a9846)

---

 bin/dnssec/dnssec-signzone.c |  2 +-

 lib/dns/nsec3.c              |  4 +-

 lib/dns/spnego.c             |  4 +-

 lib/isc/Makefile.in          |  8 +---

 lib/isc/include/isc/safe.h   | 18 ++------

 lib/isc/safe.c               | 83 ------------------------------------

 lib/isc/tests/safe_test.c    | 18 --------

 7 files changed, 11 insertions(+), 126 deletions(-)

 delete mode 100644 lib/isc/safe.c

diff --git a/bin/dnssec/dnssec-signzone.c b/bin/dnssec/dnssec-signzone.c

index 6ddaebe..d921870 100644

--- a/bin/dnssec/dnssec-signzone.c

+++ b/bin/dnssec/dnssec-signzone.c

@@ -787,7 +787,7 @@ hashlist_add_dns_name(hashlist_t *l, /*const*/ dns_name_t *name,

 static int

 hashlist_comp(const void *a, const void *b) {

-	return (isc_safe_memcompare(a, b, hash_length + 1));

+	return (memcmp(a, b, hash_length + 1));

 }

 static void

diff --git a/lib/dns/nsec3.c b/lib/dns/nsec3.c

index 6ae7ca8..01426d6 100644

--- a/lib/dns/nsec3.c

+++ b/lib/dns/nsec3.c

@@ -1963,7 +1963,7 @@ dns_nsec3_noexistnodata(dns_rdatatype_t type, dns_name_t* name,

 	 * Work out what this NSEC3 covers.

 	 * Inside (<0) or outside (>=0).

 	 */

-	scope = isc_safe_memcompare(owner, nsec3.next, nsec3.next_length);

+	scope = memcmp(owner, nsec3.next, nsec3.next_length);

 	/*

 	 * Prepare to compute all the hashes.

@@ -1987,7 +1987,7 @@ dns_nsec3_noexistnodata(dns_rdatatype_t type, dns_name_t* name,

 			return (ISC_R_IGNORE);

 		}

-		order = isc_safe_memcompare(hash, owner, length);

+		order = memcmp(hash, owner, length);

 		if (first && order == 0) {

 			/*

 			 * The hashes are the same.

diff --git a/lib/dns/spnego.c b/lib/dns/spnego.c

index ad77f24..670982a 100644

--- a/lib/dns/spnego.c

+++ b/lib/dns/spnego.c

@@ -371,7 +371,7 @@ gssapi_spnego_decapsulate(OM_uint32 *,

 /* mod_auth_kerb.c */

-static int

+static isc_boolean_t

 cmp_gss_type(gss_buffer_t token, gss_OID gssoid)

 {

 	unsigned char *p;

@@ -395,7 +395,7 @@ cmp_gss_type(gss_buffer_t token, gss_OID gssoid)

 	if (((OM_uint32) *p++) != gssoid->length)

 		return (GSS_S_DEFECTIVE_TOKEN);

-	return (isc_safe_memcompare(p, gssoid->elements, gssoid->length));

+	return (!isc_safe_memequal(p, gssoid->elements, gssoid->length));

 }

 /* accept_sec_context.c */

diff --git a/lib/isc/Makefile.in b/lib/isc/Makefile.in

index 0fd0837..8ad54bb 100644

--- a/lib/isc/Makefile.in

+++ b/lib/isc/Makefile.in

@@ -60,7 +60,7 @@ OBJS =		@ISC_EXTRA_OBJS@ @ISC_PK11_O@ @ISC_PK11_RESULT_O@ \

 		parseint.@O@ portset.@O@ quota.@O@ radix.@O@ random.@O@ \

 		ratelimiter.@O@ refcount.@O@ region.@O@ regex.@O@ result.@O@ \

 		rwlock.@O@ \

-		safe.@O@ serial.@O@ siphash.@O@ sha1.@O@ sha2.@O@ sockaddr.@O@ stats.@O@ \

+		serial.@O@ siphash.@O@ sha1.@O@ sha2.@O@ sockaddr.@O@ stats.@O@ \

 		string.@O@ strtoul.@O@ symtab.@O@ task.@O@ taskpool.@O@ \

 		tm.@O@ timer.@O@ version.@O@ \

 		${UNIXOBJS} ${NLSOBJS} ${THREADOBJS}

@@ -79,7 +79,7 @@ SRCS =		@ISC_EXTRA_SRCS@ @ISC_PK11_C@ @ISC_PK11_RESULT_C@ \

 		netaddr.c netscope.c pool.c ondestroy.c \

 		parseint.c portset.c quota.c radix.c random.c ${CHACHASRCS} \

 		ratelimiter.c refcount.c region.c regex.c result.c rwlock.c \

-		safe.c serial.c siphash.c sha1.c sha2.c sockaddr.c stats.c string.c \

+		serial.c siphash.c sha1.c sha2.c sockaddr.c stats.c string.c \

 		strtoul.c symtab.c task.c taskpool.c timer.c \

 		tm.c version.c

@@ -95,10 +95,6 @@ TESTDIRS =	@UNITTESTS@

 @BIND9_MAKE_RULES@

-safe.@O@: safe.c

-	${LIBTOOL_MODE_COMPILE} ${CC} ${ALL_CFLAGS} @CCNOOPT@ \

-		-c ${srcdir}/safe.c

-

 version.@O@: version.c

 	${LIBTOOL_MODE_COMPILE} ${CC} ${ALL_CFLAGS} \

 		-DVERSION=\"${VERSION}\" \

diff --git a/lib/isc/include/isc/safe.h b/lib/isc/include/isc/safe.h

index 66ed08b..88b8f47 100644

--- a/lib/isc/include/isc/safe.h

+++ b/lib/isc/include/isc/safe.h

@@ -15,29 +15,19 @@

 /*! \file isc/safe.h */

-#include <stdbool.h>

-

-#include <isc/types.h>

-#include <stdlib.h>

+#include <isc/lang.h>

+#include <openssl/crypto.h>

 ISC_LANG_BEGINDECLS

-bool

-isc_safe_memequal(const void *s1, const void *s2, size_t n);

+#define isc_safe_memequal(s1, s2, n) !CRYPTO_memcmp(s1, s2, n)

 /*%<

  * Returns true iff. two blocks of memory are equal, otherwise

  * false.

  *

  */

-int

-isc_safe_memcompare(const void *b1, const void *b2, size_t len);

-/*%<

- * Clone of libc memcmp() which is safe to differential timing attacks.

- */

-

-void

-isc_safe_memwipe(void *ptr, size_t len);

+#define isc_safe_memwipe(ptr, len) OPENSSL_cleanse(ptr, len)

 /*%<

  * Clear the memory of length `len` pointed to by `ptr`.

  *

diff --git a/lib/isc/safe.c b/lib/isc/safe.c

deleted file mode 100644

index 7a464b6..0000000

--- a/lib/isc/safe.c

+++ /dev/null

@@ -1,83 +0,0 @@

-/*

- * Copyright (C) Internet Systems Consortium, Inc. ("ISC")

- *

- * This Source Code Form is subject to the terms of the Mozilla Public

- * License, v. 2.0. If a copy of the MPL was not distributed with this

- * file, You can obtain one at http://mozilla.org/MPL/2.0/.

- *

- * See the COPYRIGHT file distributed with this work for additional

- * information regarding copyright ownership.

- */

-

-/*! \file */

-

-#include <config.h>

-

-#include <stdbool.h>

-

-#include <isc/safe.h>

-#include <isc/string.h>

-#include <isc/util.h>

-

-#ifdef WIN32

-#include <windows.h>

-#endif

-

-#ifdef _MSC_VER

-#pragma optimize("", off)

-#endif

-

-bool

-isc_safe_memequal(const void *s1, const void *s2, size_t n) {

-	uint8_t acc = 0;

-

-	if (n != 0U) {

-		const uint8_t *p1 = s1, *p2 = s2;

-

-		do {

-			acc |= *p1++ ^ *p2++;

-		} while (--n != 0U);

-	}

-	return (acc == 0);

-}

-

-

-int

-isc_safe_memcompare(const void *b1, const void *b2, size_t len) {

-	const unsigned char *p1 = b1, *p2 = b2;

-	size_t i;

-	int res = 0, done = 0;

-

-	for (i = 0; i < len; i++) {

-		/* lt is -1 if p1[i] < p2[i]; else 0. */

-		int lt = (p1[i] - p2[i]) >> CHAR_BIT;

-

-		/* gt is -1 if p1[i] > p2[i]; else 0. */

-		int gt = (p2[i] - p1[i]) >> CHAR_BIT;

-

-		/* cmp is 1 if p1[i] > p2[i]; -1 if p1[i] < p2[i]; else 0. */

-		int cmp = lt - gt;

-

-		/* set res = cmp if !done. */

-		res |= cmp & ~done;

-

-		/* set done if p1[i] != p2[i]. */

-		done |= lt | gt;

-	}

-

-	return (res);

-}

-

-void

-isc_safe_memwipe(void *ptr, size_t len) {

-	if (ISC_UNLIKELY(ptr == NULL || len == 0))

-		return;

-

-#ifdef WIN32

-	SecureZeroMemory(ptr, len);

-#elif HAVE_EXPLICIT_BZERO

-	explicit_bzero(ptr, len);

-#else

-	memset(ptr, 0, len);

-#endif

-}

diff --git a/lib/isc/tests/safe_test.c b/lib/isc/tests/safe_test.c

index 266ac75..60e9181 100644

--- a/lib/isc/tests/safe_test.c

+++ b/lib/isc/tests/safe_test.c

@@ -45,22 +45,6 @@ isc_safe_memequal_test(void **state) {

 				       "\x00\x00\x00\x00", 4));

 }

-/* test isc_safe_memcompare() */

-static void

-isc_safe_memcompare_test(void **state) {

-	UNUSED(state);

-

-	assert_int_equal(isc_safe_memcompare("test", "test", 4), 0);

-	assert_true(isc_safe_memcompare("test", "tesc", 4) > 0);

-	assert_true(isc_safe_memcompare("test", "tesy", 4) < 0);

-	assert_int_equal(isc_safe_memcompare("\x00\x00\x00\x00",

-					     "\x00\x00\x00\x00", 4), 0);

-	assert_true(isc_safe_memcompare("\x00\x00\x00\x00",

-					"\x00\x00\x00\x01", 4) < 0);

-	assert_true(isc_safe_memcompare("\x00\x00\x00\x02",

-					"\x00\x00\x00\x00", 4) > 0);

-}

-

 /* test isc_safe_memwipe() */

 static void

 isc_safe_memwipe_test(void **state) {

@@ -69,7 +53,6 @@ isc_safe_memwipe_test(void **state) {

 	/* These should pass. */

 	isc_safe_memwipe(NULL, 0);

 	isc_safe_memwipe((void *) -1, 0);

-	isc_safe_memwipe(NULL, 42);

 	/*

 	 * isc_safe_memwipe(ptr, size) should function same as

@@ -108,7 +91,6 @@ main(void) {

 	const struct CMUnitTest tests[] = {

 		cmocka_unit_test(isc_safe_memequal_test),

 		cmocka_unit_test(isc_safe_memwipe_test),

-		cmocka_unit_test(isc_safe_memcompare_test),

 	};

 	return (cmocka_run_group_tests(tests, NULL, NULL));

-- 

2.20.1