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-rw-r--r--crypto/Makefile1
-rw-r--r--crypto/constant_time_locl.h169
-rw-r--r--crypto/constant_time_test.c205
-rw-r--r--ssl/Makefile41
-rw-r--r--ssl/s3_cbc.c56
-rw-r--r--test/Makefile21
6 files changed, 423 insertions, 70 deletions
diff --git a/crypto/Makefile b/crypto/Makefile
index 0537913df0..874495793f 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -31,6 +31,7 @@ CPUID_OBJ=mem_clr.o
LIBS=
GENERAL=Makefile README crypto-lib.com install.com
+TEST=constant_time_test.c
LIB= $(TOP)/libcrypto.a
SHARED_LIB= libcrypto$(SHLIB_EXT)
diff --git a/crypto/constant_time_locl.h b/crypto/constant_time_locl.h
new file mode 100644
index 0000000000..782da6c8b2
--- /dev/null
+++ b/crypto/constant_time_locl.h
@@ -0,0 +1,169 @@
+/* crypto/constant_time_locl.h */
+/*
+ * Utilities for constant-time cryptography.
+ *
+ * Author: Emilia Kasper (emilia@openssl.org)
+ * Based on previous work by Bodo Moeller, Emilia Kasper, Adam Langley
+ * (Google).
+ * ====================================================================
+ * Copyright (c) 2014 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 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 acknowledgement:
+ * "This product includes cryptographic software written by
+ * Eric Young (eay@cryptsoft.com)"
+ * The word 'cryptographic' can be left out if the rouines from the library
+ * being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from
+ * the apps directory (application code) you must include an acknowledgement:
+ * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
+ * ANY EXPRESS 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 AUTHOR OR 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.
+ *
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed. i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.]
+ */
+
+#ifndef HEADER_CONSTANT_TIME_LOCL_H
+#define HEADER_CONSTANT_TIME_LOCL_H
+
+#include "e_os.h" /* For 'inline' */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * The following methods return a bitmask of all ones (0xff...f) for true
+ * and 0 for false. This is useful for choosing a value based on the result
+ * of a conditional in constant time. For example,
+ *
+ * if (a < b) {
+ * c = a;
+ * } else {
+ * c = b;
+ * }
+ *
+ * can be written as
+ *
+ * unsigned int lt = constant_time_lt(a, b);
+ * c = a & lt | b & ~lt;
+ */
+
+/*
+ * Returns the given value with the MSB copied to all the other
+ * bits. Uses the fact that arithmetic shift shifts-in the sign bit.
+ * However, this is not ensured by the C standard so you may need to
+ * replace this with something else on odd CPUs.
+ */
+static inline unsigned int constant_time_msb(unsigned int a);
+
+/*
+ * Returns 0xff..f if a < b and 0 otherwise.
+ */
+inline unsigned int constant_time_lt(unsigned int a, unsigned int b);
+/* Convenience method for getting an 8-bit mask. */
+inline unsigned char constant_time_lt_8(unsigned int a, unsigned int b);
+
+/*
+ * Returns 0xff..f if a >= b and 0 otherwise.
+ */
+inline unsigned int constant_time_ge(unsigned int a, unsigned int b);
+/* Convenience method for getting an 8-bit mask. */
+inline unsigned char constant_time_ge_8(unsigned int a, unsigned int b);
+
+/*
+ * Returns 0xff..f if a == 0 and 0 otherwise.
+ */
+inline unsigned int constant_time_is_zero(unsigned int a);
+/* Convenience method for getting an 8-bit mask. */
+inline unsigned char constant_time_is_zero_8(unsigned int a);
+
+
+/*
+ * Returns 0xff..f if a == b and 0 otherwise.
+ */
+inline unsigned int constant_time_eq(unsigned int a, unsigned int b);
+/* Convenience method for getting an 8-bit mask. */
+inline unsigned char constant_time_eq_8(unsigned int a, unsigned int b);
+
+static inline unsigned int constant_time_msb(unsigned int a)
+ {
+ return (unsigned int)((int)(a) >> (sizeof(int) * 8 - 1));
+ }
+
+inline unsigned int constant_time_lt(unsigned int a, unsigned int b)
+ {
+ unsigned int lt;
+ /* Case 1: msb(a) == msb(b). a < b iff the MSB of a - b is set.*/
+ lt = ~(a ^ b) & (a - b);
+ /* Case 2: msb(a) != msb(b). a < b iff the MSB of b is set. */
+ lt |= ~a & b;
+ return constant_time_msb(lt);
+ }
+
+inline unsigned char constant_time_lt_8(unsigned int a, unsigned int b)
+ {
+ return (unsigned char)(constant_time_lt(a, b));
+ }
+
+inline unsigned int constant_time_ge(unsigned int a, unsigned int b)
+ {
+ unsigned int ge;
+ /* Case 1: msb(a) == msb(b). a >= b iff the MSB of a - b is not set.*/
+ ge = ~((a ^ b) | (a - b));
+ /* Case 2: msb(a) != msb(b). a >= b iff the MSB of a is set. */
+ ge |= a & ~b;
+ return constant_time_msb(ge);
+ }
+
+inline unsigned char constant_time_ge_8(unsigned int a, unsigned int b)
+ {
+ return (unsigned char)(constant_time_ge(a, b));
+ }
+
+inline unsigned int constant_time_is_zero(unsigned int a)
+ {
+ return constant_time_msb(~a & (a - 1));
+ }
+
+inline unsigned char constant_time_is_zero_8(unsigned int a)
+ {
+ return (unsigned char)(constant_time_is_zero(a));
+ }
+
+inline unsigned int constant_time_eq(unsigned int a, unsigned int b)
+ {
+ return constant_time_is_zero(a ^ b);
+ }
+
+inline unsigned char constant_time_eq_8(unsigned int a, unsigned int b)
+ {
+ return (unsigned char)(constant_time_eq(a, b));
+ }
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* HEADER_CONSTANT_TIME_LOCL_H */
diff --git a/crypto/constant_time_test.c b/crypto/constant_time_test.c
new file mode 100644
index 0000000000..89fad7d3f2
--- /dev/null
+++ b/crypto/constant_time_test.c
@@ -0,0 +1,205 @@
+/* crypto/constant_time_test.c */
+/*
+ * Utilities for constant-time cryptography.
+ *
+ * Author: Emilia Kasper (emilia@openssl.org)
+ * Based on previous work by Bodo Moeller, Emilia Kasper, Adam Langley
+ * (Google).
+ * ====================================================================
+ * Copyright (c) 2014 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 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 acknowledgement:
+ * "This product includes cryptographic software written by
+ * Eric Young (eay@cryptsoft.com)"
+ * The word 'cryptographic' can be left out if the rouines from the library
+ * being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from
+ * the apps directory (application code) you must include an acknowledgement:
+ * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
+ * ANY EXPRESS 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 AUTHOR OR 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.
+ *
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed. i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.]
+ */
+
+#include "../crypto/constant_time_locl.h"
+
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static const unsigned int CONSTTIME_TRUE = ~0;
+static const unsigned int CONSTTIME_FALSE = 0;
+static const unsigned char CONSTTIME_TRUE_8 = ~0;
+static const unsigned char CONSTTIME_FALSE_8 = 0;
+
+static int test_binary_op(unsigned int (*op)(unsigned int a, unsigned int b),
+ const char* op_name, unsigned int a, unsigned int b, int is_true)
+ {
+ unsigned c = op(a, b);
+ if (is_true && c != CONSTTIME_TRUE)
+ {
+ fprintf(stderr, "Test failed for %s(%du, %du): expected %du "
+ "(TRUE), got %du\n", op_name, a, b, CONSTTIME_TRUE, c);
+ return 1;
+ }
+ else if (!is_true && c != CONSTTIME_FALSE)
+ {
+ fprintf(stderr, "Test failed for %s(%du, %du): expected %du "
+ "(FALSE), got %du\n", op_name, a, b, CONSTTIME_FALSE,
+ c);
+ return 1;
+ }
+ return 0;
+ }
+
+static int test_binary_op_8(unsigned char (*op)(unsigned int a, unsigned int b),
+ const char* op_name, unsigned int a, unsigned int b, int is_true)
+ {
+ unsigned char c = op(a, b);
+ if (is_true && c != CONSTTIME_TRUE_8)
+ {
+ fprintf(stderr, "Test failed for %s(%du, %du): expected %u "
+ "(TRUE), got %u\n", op_name, a, b, CONSTTIME_TRUE_8, c);
+ return 1;
+ }
+ else if (!is_true && c != CONSTTIME_FALSE_8)
+ {
+ fprintf(stderr, "Test failed for %s(%du, %du): expected %u "
+ "(FALSE), got %u\n", op_name, a, b, CONSTTIME_FALSE_8,
+ c);
+ return 1;
+ }
+ return 0;
+ }
+
+static int test_is_zero(unsigned int a)
+ {
+ unsigned int c = constant_time_is_zero(a);
+ if (a == 0 && c != CONSTTIME_TRUE)
+ {
+ fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
+ "expected %du (TRUE), got %du\n", a, CONSTTIME_TRUE, c);
+ return 1;
+ }
+ else if (a != 0 && c != CONSTTIME_FALSE)
+ {
+ fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
+ "expected %du (FALSE), got %du\n", a, CONSTTIME_FALSE,
+ c);
+ return 1;
+ }
+ return 0;
+ }
+
+static int test_is_zero_8(unsigned int a)
+ {
+ unsigned char c = constant_time_is_zero_8(a);
+ if (a == 0 && c != CONSTTIME_TRUE_8)
+ {
+ fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
+ "expected %u (TRUE), got %u\n", a, CONSTTIME_TRUE_8, c);
+ return 1;
+ }
+ else if (a != 0 && c != CONSTTIME_FALSE)
+ {
+ fprintf(stderr, "Test failed for constant_time_is_zero(%du): "
+ "expected %u (FALSE), got %u\n", a, CONSTTIME_FALSE_8,
+ c);
+ return 1;
+ }
+ return 0;
+ }
+
+static unsigned int test_values[] = {0, 1, 1024, 12345, 32000, UINT_MAX/2-1,
+ UINT_MAX/2, UINT_MAX/2+1, UINT_MAX-1,
+ UINT_MAX};
+
+int main(int argc, char *argv[])
+ {
+ unsigned int a, b, i, j;
+ int num_failed = 0, num_all = 0;
+ fprintf(stdout, "Testing constant time operations...\n");
+
+ for (i = 0; i < sizeof(test_values)/sizeof(int); ++i)
+ {
+ a = test_values[i];
+ num_failed += test_is_zero(a);
+ num_failed += test_is_zero_8(a);
+ num_failed += test_binary_op(&constant_time_lt,
+ "constant_time_lt", a, a, 0);
+ num_failed += test_binary_op_8(&constant_time_lt_8,
+ "constant_time_lt_8", a, a, 0);
+ num_failed += test_binary_op(&constant_time_ge,
+ "constant_time_ge", a, a, 1);
+ num_failed += test_binary_op_8(&constant_time_ge_8,
+ "constant_time_ge_8", a, a, 1);
+ num_failed += test_binary_op(&constant_time_eq,
+ "constant_time_eq", a, a, 1);
+ num_failed += test_binary_op_8(&constant_time_eq_8,
+ "constant_time_eq_8", a, a, 1);
+ num_all += 8;
+ for (j = i + 1; j < sizeof(test_values)/sizeof(int); ++j)
+ {
+ b = test_values[j];
+ num_failed += test_binary_op(&constant_time_lt,
+ "constant_time_lt", a, b, a < b);
+ num_failed += test_binary_op_8(&constant_time_lt_8,
+ "constant_time_lt_8", a, b, a < b);
+ num_failed += test_binary_op(&constant_time_lt,
+ "constant_time_lt_8", b, a, b < a);
+ num_failed += test_binary_op_8(&constant_time_lt_8,
+ "constant_time_lt_8", b, a, b < a);
+ num_failed += test_binary_op(&constant_time_ge,
+ "constant_time_ge", a, b, a >= b);
+ num_failed += test_binary_op_8(&constant_time_ge_8,
+ "constant_time_ge_8", a, b, a >= b);
+ num_failed += test_binary_op(&constant_time_ge,
+ "constant_time_ge", b, a, b >= a);
+ num_failed += test_binary_op_8(&constant_time_ge_8,
+ "constant_time_ge_8", b, a, b >= a);
+ num_failed += test_binary_op(&constant_time_eq,
+ "constant_time_eq", a, b, a == b);
+ num_failed += test_binary_op_8(&constant_time_eq_8,
+ "constant_time_eq_8", a, b, a == b);
+ num_failed += test_binary_op(&constant_time_eq,
+ "constant_time_eq", b, a, b == a);
+ num_failed += test_binary_op_8(&constant_time_eq_8,
+ "constant_time_eq_8", b, a, b == a);
+ num_all += 12;
+ }
+ }
+
+ if (!num_failed)
+ {
+ fprintf(stdout, "ok (ran %d tests)\n", num_all);
+ return EXIT_SUCCESS;
+ }
+ else
+ {
+ fprintf(stdout, "%d of %d tests failed!\n", num_failed, num_all);
+ return EXIT_FAILURE;
+ }
+ }
diff --git a/ssl/Makefile b/ssl/Makefile
index c1110e6274..70446b95de 100644
--- a/ssl/Makefile
+++ b/ssl/Makefile
@@ -547,26 +547,27 @@ s3_both.o: ../include/openssl/ssl23.h ../include/openssl/ssl3.h
s3_both.o: ../include/openssl/stack.h ../include/openssl/symhacks.h
s3_both.o: ../include/openssl/tls1.h ../include/openssl/x509.h
s3_both.o: ../include/openssl/x509_vfy.h s3_both.c ssl_locl.h
-s3_cbc.o: ../e_os.h ../include/openssl/asn1.h ../include/openssl/bio.h
-s3_cbc.o: ../include/openssl/buffer.h ../include/openssl/comp.h
-s3_cbc.o: ../include/openssl/crypto.h ../include/openssl/dsa.h
-s3_cbc.o: ../include/openssl/dtls1.h ../include/openssl/e_os2.h
-s3_cbc.o: ../include/openssl/ec.h ../include/openssl/ecdh.h
-s3_cbc.o: ../include/openssl/ecdsa.h ../include/openssl/err.h
-s3_cbc.o: ../include/openssl/evp.h ../include/openssl/hmac.h
-s3_cbc.o: ../include/openssl/kssl.h ../include/openssl/lhash.h
-s3_cbc.o: ../include/openssl/md5.h ../include/openssl/obj_mac.h
-s3_cbc.o: ../include/openssl/objects.h ../include/openssl/opensslconf.h
-s3_cbc.o: ../include/openssl/opensslv.h ../include/openssl/ossl_typ.h
-s3_cbc.o: ../include/openssl/pem.h ../include/openssl/pem2.h
-s3_cbc.o: ../include/openssl/pkcs7.h ../include/openssl/pqueue.h
-s3_cbc.o: ../include/openssl/rsa.h ../include/openssl/safestack.h
-s3_cbc.o: ../include/openssl/sha.h ../include/openssl/srtp.h
-s3_cbc.o: ../include/openssl/ssl.h ../include/openssl/ssl2.h
-s3_cbc.o: ../include/openssl/ssl23.h ../include/openssl/ssl3.h
-s3_cbc.o: ../include/openssl/stack.h ../include/openssl/symhacks.h
-s3_cbc.o: ../include/openssl/tls1.h ../include/openssl/x509.h
-s3_cbc.o: ../include/openssl/x509_vfy.h s3_cbc.c ssl_locl.h
+s3_cbc.o: ../crypto/constant_time_locl.h ../e_os.h ../include/openssl/asn1.h
+s3_cbc.o: ../include/openssl/bio.h ../include/openssl/buffer.h
+s3_cbc.o: ../include/openssl/comp.h ../include/openssl/crypto.h
+s3_cbc.o: ../include/openssl/dsa.h ../include/openssl/dtls1.h
+s3_cbc.o: ../include/openssl/e_os2.h ../include/openssl/ec.h
+s3_cbc.o: ../include/openssl/ecdh.h ../include/openssl/ecdsa.h
+s3_cbc.o: ../include/openssl/err.h ../include/openssl/evp.h
+s3_cbc.o: ../include/openssl/hmac.h ../include/openssl/kssl.h
+s3_cbc.o: ../include/openssl/lhash.h ../include/openssl/md5.h
+s3_cbc.o: ../include/openssl/obj_mac.h ../include/openssl/objects.h
+s3_cbc.o: ../include/openssl/opensslconf.h ../include/openssl/opensslv.h
+s3_cbc.o: ../include/openssl/ossl_typ.h ../include/openssl/pem.h
+s3_cbc.o: ../include/openssl/pem2.h ../include/openssl/pkcs7.h
+s3_cbc.o: ../include/openssl/pqueue.h ../include/openssl/rsa.h
+s3_cbc.o: ../include/openssl/safestack.h ../include/openssl/sha.h
+s3_cbc.o: ../include/openssl/srtp.h ../include/openssl/ssl.h
+s3_cbc.o: ../include/openssl/ssl2.h ../include/openssl/ssl23.h
+s3_cbc.o: ../include/openssl/ssl3.h ../include/openssl/stack.h
+s3_cbc.o: ../include/openssl/symhacks.h ../include/openssl/tls1.h
+s3_cbc.o: ../include/openssl/x509.h ../include/openssl/x509_vfy.h s3_cbc.c
+s3_cbc.o: ssl_locl.h
s3_clnt.o: ../e_os.h ../include/openssl/asn1.h ../include/openssl/bio.h
s3_clnt.o: ../include/openssl/bn.h ../include/openssl/buffer.h
s3_clnt.o: ../include/openssl/comp.h ../include/openssl/crypto.h
diff --git a/ssl/s3_cbc.c b/ssl/s3_cbc.c
index 73e12b6799..f15c5b5966 100644
--- a/ssl/s3_cbc.c
+++ b/ssl/s3_cbc.c
@@ -53,6 +53,7 @@
*
*/
+#include "../crypto/constant_time_locl.h"
#include "ssl_locl.h"
#include <openssl/md5.h>
@@ -67,37 +68,6 @@
* supported by TLS.) */
#define MAX_HASH_BLOCK_SIZE 128
-/* Some utility functions are needed:
- *
- * These macros return the given value with the MSB copied to all the other
- * bits. They use the fact that arithmetic shift shifts-in the sign bit.
- * However, this is not ensured by the C standard so you may need to replace
- * them with something else on odd CPUs. */
-#define DUPLICATE_MSB_TO_ALL(x) ( (unsigned)( (int)(x) >> (sizeof(int)*8-1) ) )
-#define DUPLICATE_MSB_TO_ALL_8(x) ((unsigned char)(DUPLICATE_MSB_TO_ALL(x)))
-
-/* constant_time_lt returns 0xff if a<b and 0x00 otherwise. */
-static unsigned constant_time_lt(unsigned a, unsigned b)
- {
- a -= b;
- return DUPLICATE_MSB_TO_ALL(a);
- }
-
-/* constant_time_ge returns 0xff if a>=b and 0x00 otherwise. */
-static unsigned constant_time_ge(unsigned a, unsigned b)
- {
- a -= b;
- return DUPLICATE_MSB_TO_ALL(~a);
- }
-
-/* constant_time_eq_8 returns 0xff if a==b and 0x00 otherwise. */
-static unsigned char constant_time_eq_8(unsigned a, unsigned b)
- {
- unsigned c = a ^ b;
- c--;
- return DUPLICATE_MSB_TO_ALL_8(c);
- }
-
/* ssl3_cbc_remove_padding removes padding from the decrypted, SSLv3, CBC
* record in |rec| by updating |rec->length| in constant time.
*
@@ -125,7 +95,7 @@ int ssl3_cbc_remove_padding(const SSL* s,
good &= constant_time_ge(block_size, padding_length+1);
rec->length -= good & (padding_length+1);
return (int)((good & 1) | (~good & -1));
-}
+ }
/* tls1_cbc_remove_padding removes the CBC padding from the decrypted, TLS, CBC
* record in |rec| in constant time and returns 1 if the padding is valid and
@@ -207,7 +177,7 @@ int tls1_cbc_remove_padding(const SSL* s,
for (i = 0; i < to_check; i++)
{
- unsigned char mask = constant_time_ge(padding_length, i);
+ unsigned char mask = constant_time_ge_8(padding_length, i);
unsigned char b = rec->data[rec->length-1-i];
/* The final |padding_length+1| bytes should all have the value
* |padding_length|. Therefore the XOR should be zero. */
@@ -215,15 +185,9 @@ int tls1_cbc_remove_padding(const SSL* s,
}
/* If any of the final |padding_length+1| bytes had the wrong value,
- * one or more of the lower eight bits of |good| will be cleared. We
- * AND the bottom 8 bits together and duplicate the result to all the
- * bits. */
- good &= good >> 4;
- good &= good >> 2;
- good &= good >> 1;
- good <<= sizeof(good)*8-1;
- good = DUPLICATE_MSB_TO_ALL(good);
-
+ * one or more of the lower eight bits of |good| will be cleared.
+ */
+ good = constant_time_eq(0xff, good & 0xff);
rec->length -= good & (padding_length+1);
return (int)((good & 1) | (~good & -1));
@@ -293,8 +257,8 @@ void ssl3_cbc_copy_mac(unsigned char* out,
memset(rotated_mac, 0, md_size);
for (i = scan_start, j = 0; i < rec->orig_len; i++)
{
- unsigned char mac_started = constant_time_ge(i, mac_start);
- unsigned char mac_ended = constant_time_ge(i, mac_end);
+ unsigned char mac_started = constant_time_ge_8(i, mac_start);
+ unsigned char mac_ended = constant_time_ge_8(i, mac_end);
unsigned char b = rec->data[i];
rotated_mac[j++] |= b & mac_started & ~mac_ended;
j &= constant_time_lt(j,md_size);
@@ -681,8 +645,8 @@ void ssl3_cbc_digest_record(
b = data[k-header_length];
k++;
- is_past_c = is_block_a & constant_time_ge(j, c);
- is_past_cp1 = is_block_a & constant_time_ge(j, c+1);
+ is_past_c = is_block_a & constant_time_ge_8(j, c);
+ is_past_cp1 = is_block_a & constant_time_ge_8(j, c+1);
/* If this is the block containing the end of the
* application data, and we are at the offset for the
* 0x80 value, then overwrite b with 0x80. */
diff --git a/test/Makefile b/test/Makefile
index 4a06599124..7680fab1f9 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -87,6 +87,7 @@ FIPS_TEST_SUITE=fips_test_suite
FIPS_CMACTEST= fips_cmactest
FIPS_ALGVS= fips_algvs
HEARTBEATTEST= heartbeat_test
+CONSTTIMETEST= constant_time_test
TESTS= alltests
@@ -100,7 +101,8 @@ EXE= $(BNTEST)$(EXE_EXT) $(ECTEST)$(EXE_EXT) $(ECDSATEST)$(EXE_EXT) $(ECDHTEST)
$(BFTEST)$(EXE_EXT) $(CASTTEST)$(EXE_EXT) $(SSLTEST)$(EXE_EXT) \
$(EXPTEST)$(EXE_EXT) $(DSATEST)$(EXE_EXT) $(RSATEST)$(EXE_EXT) \
$(EVPTEST)$(EXE_EXT) $(IGETEST)$(EXE_EXT) $(JPAKETEST)$(EXE_EXT) $(SRPTEST)$(EXE_EXT) \
- $(V3NAMETEST)$(EXE_EXT) $(HEARTBEATTEST)$(EXE_EXT) $(P5_CRPT2_TEST)$(EXE_EXT)
+ $(V3NAMETEST)$(EXE_EXT) $(HEARTBEATTEST)$(EXE_EXT) $(P5_CRPT2_TEST)$(EXE_EXT) \
+ $(CONSTTIMETEST)$(EXE_EXT)
FIPSEXE=$(FIPS_SHATEST)$(EXE_EXT) $(FIPS_DESTEST)$(EXE_EXT) \
$(FIPS_RANDTEST)$(EXE_EXT) $(FIPS_AESTEST)$(EXE_EXT) \
@@ -130,7 +132,7 @@ OBJ= $(BNTEST).o $(ECTEST).o $(ECDSATEST).o $(ECDHTEST).o $(IDEATEST).o \
$(FIPS_ECDHVS).o $(FIPS_CMACTEST).o $(FIPS_ALGVS).o \
$(EVPTEST).o $(IGETEST).o $(JPAKETEST).o $(V3NAMETEST).o \
$(GOST2814789TEST).o $(HEARTBEATTEST).o $(P5_CRPT2_TEST).o \
- testutil.o
+ $(CONSTTIMETEST).o testutil.o
SRC= $(BNTEST).c $(ECTEST).c $(ECDSATEST).c $(ECDHTEST).c $(IDEATEST).c \
$(MD2TEST).c $(MD4TEST).c $(MD5TEST).c \
@@ -147,7 +149,7 @@ SRC= $(BNTEST).c $(ECTEST).c $(ECDSATEST).c $(ECDHTEST).c $(IDEATEST).c \
$(FIPS_ECDHVS).c $(FIPS_CMACTEST).c $(FIPS_ALGVS).c \
$(EVPTEST).c $(IGETEST).c $(JPAKETEST).c $(V3NAMETEST).c \
$(GOST2814789TEST).c $(HEARTBEATTEST).c $(P5_CRPT2_TEST).c \
- testutil.c
+ $(CONSTTIMETEST).c testutil.c
EXHEADER=
HEADER= testutil.h $(EXHEADER)
@@ -195,7 +197,8 @@ alltests: \
test_gen test_req test_pkcs7 test_verify test_dh test_dsa \
test_ss test_ca test_engine test_evp test_ssl test_tsa test_ige \
test_jpake test_srp test_cms test_v3name test_ocsp \
- test_gost2814789 test_heartbeat test_p5_crpt2
+ test_gost2814789 test_heartbeat test_p5_crpt2 \
+ test_constant_time
test_evp: $(EVPTEST)$(EXE_EXT) evptests.txt
../util/shlib_wrap.sh ./$(EVPTEST) evptests.txt
@@ -388,6 +391,10 @@ test_ocsp: ../apps/openssl$(EXE_EXT) tocsp
test_heartbeat: $(HEARTBEATTEST)$(EXE_EXT)
../util/shlib_wrap.sh ./$(HEARTBEATTEST)
+test_constant_time: $(CONSTTIMETEST)$(EXE_EXT)
+ @echo "Test constant time utilites"
+ ../util/shlib_wrap.sh ./$(CONSTTIMETEST)
+
lint:
lint -DLINT $(INCLUDES) $(SRC)>fluff
@@ -629,6 +636,9 @@ $(V3NAMETEST)$(EXE_EXT): $(V3NAMETEST).o $(DLIBCRYPTO)
$(HEARTBEATTEST)$(EXE_EXT): $(HEARTBEATTEST).o $(DLIBCRYPTO) testutil.o
@target=$(HEARTBEATTEST) testutil=testutil.o; $(BUILD_CMD_STATIC)
+$(CONSTTIMETEST)$(EXE_EXT): $(CONSTTIMETEST).o
+ @target=$(CONSTTIMETEST) $(BUILD_CMD)
+
#$(AESTEST).o: $(AESTEST).c
# $(CC) -c $(CFLAGS) -DINTERMEDIATE_VALUE_KAT -DTRACE_KAT_MCT $(AESTEST).c
@@ -663,6 +673,9 @@ bntest.o: ../include/openssl/symhacks.h ../include/openssl/x509.h
bntest.o: ../include/openssl/x509_vfy.h bntest.c
casttest.o: ../e_os.h ../include/openssl/cast.h ../include/openssl/e_os2.h
casttest.o: ../include/openssl/opensslconf.h casttest.c
+constant_time_test.o: ../crypto/constant_time_locl.h ../e_os.h
+constant_time_test.o: ../include/openssl/e_os2.h
+constant_time_test.o: ../include/openssl/opensslconf.h constant_time_test.c
destest.o: ../include/openssl/des.h ../include/openssl/des_old.h
destest.o: ../include/openssl/e_os2.h ../include/openssl/opensslconf.h
destest.o: ../include/openssl/ossl_typ.h ../include/openssl/safestack.h