[PATCH 5.10 62/84] crypto: memneq - move into lib/

From: Greg Kroah-Hartman
Date: Mon Jun 20 2022 - 09:16:29 EST


From: Jason A. Donenfeld <Jason@xxxxxxxxx>

commit abfed87e2a12bd246047d78c01d81eb9529f1d06 upstream.

This is used by code that doesn't need CONFIG_CRYPTO, so move this into
lib/ with a Kconfig option so that it can be selected by whatever needs
it.

This fixes a linker error Zheng pointed out when
CRYPTO_MANAGER_DISABLE_TESTS!=y and CRYPTO=m:

lib/crypto/curve25519-selftest.o: In function `curve25519_selftest':
curve25519-selftest.c:(.init.text+0x60): undefined reference to `__crypto_memneq'
curve25519-selftest.c:(.init.text+0xec): undefined reference to `__crypto_memneq'
curve25519-selftest.c:(.init.text+0x114): undefined reference to `__crypto_memneq'
curve25519-selftest.c:(.init.text+0x154): undefined reference to `__crypto_memneq'

Reported-by: Zheng Bin <zhengbin13@xxxxxxxxxx>
Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: aa127963f1ca ("crypto: lib/curve25519 - re-add selftests")
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
crypto/Kconfig | 1 +
crypto/Makefile | 2 +-
lib/Kconfig | 3 +++
lib/Makefile | 1 +
lib/crypto/Kconfig | 1 +
{crypto => lib}/memneq.c | 0
crypto/Kconfig | 1
crypto/Makefile | 2
crypto/memneq.c | 168 -----------------------------------------------------
lib/Kconfig | 3
lib/Makefile | 1
lib/crypto/Kconfig | 1
lib/memneq.c | 168 +++++++++++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 175 insertions(+), 169 deletions(-)
rename {crypto => lib}/memneq.c (100%)

--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -15,6 +15,7 @@ source "crypto/async_tx/Kconfig"
#
menuconfig CRYPTO
tristate "Cryptographic API"
+ select LIB_MEMNEQ
help
This option provides the core Cryptographic API.

--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -4,7 +4,7 @@
#

obj-$(CONFIG_CRYPTO) += crypto.o
-crypto-y := api.o cipher.o compress.o memneq.o
+crypto-y := api.o cipher.o compress.o

obj-$(CONFIG_CRYPTO_ENGINE) += crypto_engine.o
obj-$(CONFIG_CRYPTO_FIPS) += fips.o
--- a/crypto/memneq.c
+++ /dev/null
@@ -1,168 +0,0 @@
-/*
- * Constant-time equality testing of memory regions.
- *
- * Authors:
- *
- * James Yonan <james@xxxxxxxxxxx>
- * Daniel Borkmann <dborkman@xxxxxxxxxx>
- *
- * This file is provided under a dual BSD/GPLv2 license. When using or
- * redistributing this file, you may do so under either license.
- *
- * GPL LICENSE SUMMARY
- *
- * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- * The full GNU General Public License is included in this distribution
- * in the file called LICENSE.GPL.
- *
- * BSD LICENSE
- *
- * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * 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.
- * * Neither the name of OpenVPN Technologies nor the names of its
- * contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "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 COPYRIGHT
- * OWNER 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.
- */
-
-#include <crypto/algapi.h>
-
-#ifndef __HAVE_ARCH_CRYPTO_MEMNEQ
-
-/* Generic path for arbitrary size */
-static inline unsigned long
-__crypto_memneq_generic(const void *a, const void *b, size_t size)
-{
- unsigned long neq = 0;
-
-#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
- while (size >= sizeof(unsigned long)) {
- neq |= *(unsigned long *)a ^ *(unsigned long *)b;
- OPTIMIZER_HIDE_VAR(neq);
- a += sizeof(unsigned long);
- b += sizeof(unsigned long);
- size -= sizeof(unsigned long);
- }
-#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
- while (size > 0) {
- neq |= *(unsigned char *)a ^ *(unsigned char *)b;
- OPTIMIZER_HIDE_VAR(neq);
- a += 1;
- b += 1;
- size -= 1;
- }
- return neq;
-}
-
-/* Loop-free fast-path for frequently used 16-byte size */
-static inline unsigned long __crypto_memneq_16(const void *a, const void *b)
-{
- unsigned long neq = 0;
-
-#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
- if (sizeof(unsigned long) == 8) {
- neq |= *(unsigned long *)(a) ^ *(unsigned long *)(b);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned long *)(a+8) ^ *(unsigned long *)(b+8);
- OPTIMIZER_HIDE_VAR(neq);
- } else if (sizeof(unsigned int) == 4) {
- neq |= *(unsigned int *)(a) ^ *(unsigned int *)(b);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned int *)(a+4) ^ *(unsigned int *)(b+4);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned int *)(a+8) ^ *(unsigned int *)(b+8);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned int *)(a+12) ^ *(unsigned int *)(b+12);
- OPTIMIZER_HIDE_VAR(neq);
- } else
-#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
- {
- neq |= *(unsigned char *)(a) ^ *(unsigned char *)(b);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+1) ^ *(unsigned char *)(b+1);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+2) ^ *(unsigned char *)(b+2);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+3) ^ *(unsigned char *)(b+3);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+4) ^ *(unsigned char *)(b+4);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+5) ^ *(unsigned char *)(b+5);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+6) ^ *(unsigned char *)(b+6);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+7) ^ *(unsigned char *)(b+7);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+8) ^ *(unsigned char *)(b+8);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+9) ^ *(unsigned char *)(b+9);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+10) ^ *(unsigned char *)(b+10);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+11) ^ *(unsigned char *)(b+11);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+12) ^ *(unsigned char *)(b+12);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+13) ^ *(unsigned char *)(b+13);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+14) ^ *(unsigned char *)(b+14);
- OPTIMIZER_HIDE_VAR(neq);
- neq |= *(unsigned char *)(a+15) ^ *(unsigned char *)(b+15);
- OPTIMIZER_HIDE_VAR(neq);
- }
-
- return neq;
-}
-
-/* Compare two areas of memory without leaking timing information,
- * and with special optimizations for common sizes. Users should
- * not call this function directly, but should instead use
- * crypto_memneq defined in crypto/algapi.h.
- */
-noinline unsigned long __crypto_memneq(const void *a, const void *b,
- size_t size)
-{
- switch (size) {
- case 16:
- return __crypto_memneq_16(a, b);
- default:
- return __crypto_memneq_generic(a, b, size);
- }
-}
-EXPORT_SYMBOL(__crypto_memneq);
-
-#endif /* __HAVE_ARCH_CRYPTO_MEMNEQ */
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -103,6 +103,9 @@ config INDIRECT_PIO

source "lib/crypto/Kconfig"

+config LIB_MEMNEQ
+ bool
+
config CRC_CCITT
tristate "CRC-CCITT functions"
help
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -248,6 +248,7 @@ obj-$(CONFIG_DIMLIB) += dim/
obj-$(CONFIG_SIGNATURE) += digsig.o

lib-$(CONFIG_CLZ_TAB) += clz_tab.o
+lib-$(CONFIG_LIB_MEMNEQ) += memneq.o

obj-$(CONFIG_GENERIC_STRNCPY_FROM_USER) += strncpy_from_user.o
obj-$(CONFIG_GENERIC_STRNLEN_USER) += strnlen_user.o
--- a/lib/crypto/Kconfig
+++ b/lib/crypto/Kconfig
@@ -71,6 +71,7 @@ config CRYPTO_LIB_CURVE25519
tristate "Curve25519 scalar multiplication library"
depends on CRYPTO_ARCH_HAVE_LIB_CURVE25519 || !CRYPTO_ARCH_HAVE_LIB_CURVE25519
select CRYPTO_LIB_CURVE25519_GENERIC if CRYPTO_ARCH_HAVE_LIB_CURVE25519=n
+ select LIB_MEMNEQ
help
Enable the Curve25519 library interface. This interface may be
fulfilled by either the generic implementation or an arch-specific
--- /dev/null
+++ b/lib/memneq.c
@@ -0,0 +1,168 @@
+/*
+ * Constant-time equality testing of memory regions.
+ *
+ * Authors:
+ *
+ * James Yonan <james@xxxxxxxxxxx>
+ * Daniel Borkmann <dborkman@xxxxxxxxxx>
+ *
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2013 OpenVPN Technologies, Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * 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.
+ * * Neither the name of OpenVPN Technologies nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "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 COPYRIGHT
+ * OWNER 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.
+ */
+
+#include <crypto/algapi.h>
+
+#ifndef __HAVE_ARCH_CRYPTO_MEMNEQ
+
+/* Generic path for arbitrary size */
+static inline unsigned long
+__crypto_memneq_generic(const void *a, const void *b, size_t size)
+{
+ unsigned long neq = 0;
+
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
+ while (size >= sizeof(unsigned long)) {
+ neq |= *(unsigned long *)a ^ *(unsigned long *)b;
+ OPTIMIZER_HIDE_VAR(neq);
+ a += sizeof(unsigned long);
+ b += sizeof(unsigned long);
+ size -= sizeof(unsigned long);
+ }
+#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
+ while (size > 0) {
+ neq |= *(unsigned char *)a ^ *(unsigned char *)b;
+ OPTIMIZER_HIDE_VAR(neq);
+ a += 1;
+ b += 1;
+ size -= 1;
+ }
+ return neq;
+}
+
+/* Loop-free fast-path for frequently used 16-byte size */
+static inline unsigned long __crypto_memneq_16(const void *a, const void *b)
+{
+ unsigned long neq = 0;
+
+#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
+ if (sizeof(unsigned long) == 8) {
+ neq |= *(unsigned long *)(a) ^ *(unsigned long *)(b);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned long *)(a+8) ^ *(unsigned long *)(b+8);
+ OPTIMIZER_HIDE_VAR(neq);
+ } else if (sizeof(unsigned int) == 4) {
+ neq |= *(unsigned int *)(a) ^ *(unsigned int *)(b);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned int *)(a+4) ^ *(unsigned int *)(b+4);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned int *)(a+8) ^ *(unsigned int *)(b+8);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned int *)(a+12) ^ *(unsigned int *)(b+12);
+ OPTIMIZER_HIDE_VAR(neq);
+ } else
+#endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
+ {
+ neq |= *(unsigned char *)(a) ^ *(unsigned char *)(b);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+1) ^ *(unsigned char *)(b+1);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+2) ^ *(unsigned char *)(b+2);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+3) ^ *(unsigned char *)(b+3);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+4) ^ *(unsigned char *)(b+4);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+5) ^ *(unsigned char *)(b+5);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+6) ^ *(unsigned char *)(b+6);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+7) ^ *(unsigned char *)(b+7);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+8) ^ *(unsigned char *)(b+8);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+9) ^ *(unsigned char *)(b+9);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+10) ^ *(unsigned char *)(b+10);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+11) ^ *(unsigned char *)(b+11);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+12) ^ *(unsigned char *)(b+12);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+13) ^ *(unsigned char *)(b+13);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+14) ^ *(unsigned char *)(b+14);
+ OPTIMIZER_HIDE_VAR(neq);
+ neq |= *(unsigned char *)(a+15) ^ *(unsigned char *)(b+15);
+ OPTIMIZER_HIDE_VAR(neq);
+ }
+
+ return neq;
+}
+
+/* Compare two areas of memory without leaking timing information,
+ * and with special optimizations for common sizes. Users should
+ * not call this function directly, but should instead use
+ * crypto_memneq defined in crypto/algapi.h.
+ */
+noinline unsigned long __crypto_memneq(const void *a, const void *b,
+ size_t size)
+{
+ switch (size) {
+ case 16:
+ return __crypto_memneq_16(a, b);
+ default:
+ return __crypto_memneq_generic(a, b, size);
+ }
+}
+EXPORT_SYMBOL(__crypto_memneq);
+
+#endif /* __HAVE_ARCH_CRYPTO_MEMNEQ */