summaryrefslogtreecommitdiffstats
path: root/crypto
diff options
context:
space:
mode:
authorHerbert Xu <herbert@gondor.apana.org.au>2013-09-07 12:53:35 +1000
committerHerbert Xu <herbert@gondor.apana.org.au>2013-09-07 12:53:35 +1000
commiteeca9fad52fc4bfdf42c38bfcf383e932eb3e9d6 (patch)
treecc51c880459d41c0e8d7576405bef4c987bc7aa0 /crypto
parentff6f83fc9d44db09997937c3475d525a6866fbb4 (diff)
parentb48a97be8e6c2afdba2f3b61fd88c3c7743fbd73 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux
Merge upstream tree in order to reinstate crct10dif.
Diffstat (limited to 'crypto')
-rw-r--r--crypto/Kconfig35
-rw-r--r--crypto/Makefile3
-rw-r--r--crypto/crct10dif.c178
-rw-r--r--crypto/lz4.c106
-rw-r--r--crypto/lz4hc.c106
-rw-r--r--crypto/tcrypt.c8
-rw-r--r--crypto/testmgr.c10
-rw-r--r--crypto/testmgr.h33
8 files changed, 230 insertions, 249 deletions
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 904ffe83856..aca01164f00 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -376,25 +376,6 @@ config CRYPTO_CRC32_PCLMUL
which will enable any routine to use the CRC-32-IEEE 802.3 checksum
and gain better performance as compared with the table implementation.
-config CRYPTO_CRCT10DIF
- tristate "CRCT10DIF algorithm"
- select CRYPTO_HASH
- help
- CRC T10 Data Integrity Field computation is being cast as
- a crypto transform. This allows for faster crc t10 diff
- transforms to be used if they are available.
-
-config CRYPTO_CRCT10DIF_PCLMUL
- tristate "CRCT10DIF PCLMULQDQ hardware acceleration"
- depends on X86 && 64BIT && CRC_T10DIF
- select CRYPTO_HASH
- help
- For x86_64 processors with SSE4.2 and PCLMULQDQ supported,
- CRC T10 DIF PCLMULQDQ computation can be hardware
- accelerated PCLMULQDQ instruction. This option will create
- 'crct10dif-plcmul' module, which is faster when computing the
- crct10dif checksum as compared with the generic table implementation.
-
config CRYPTO_GHASH
tristate "GHASH digest algorithm"
select CRYPTO_GF128MUL
@@ -1336,6 +1317,22 @@ config CRYPTO_842
help
This is the 842 algorithm.
+config CRYPTO_LZ4
+ tristate "LZ4 compression algorithm"
+ select CRYPTO_ALGAPI
+ select LZ4_COMPRESS
+ select LZ4_DECOMPRESS
+ help
+ This is the LZ4 algorithm.
+
+config CRYPTO_LZ4HC
+ tristate "LZ4HC compression algorithm"
+ select CRYPTO_ALGAPI
+ select LZ4HC_COMPRESS
+ select LZ4_DECOMPRESS
+ help
+ This is the LZ4 high compression mode algorithm.
+
comment "Random Number Generation"
config CRYPTO_ANSI_CPRNG
diff --git a/crypto/Makefile b/crypto/Makefile
index 62af87df872..2ba0df2f908 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -83,9 +83,10 @@ obj-$(CONFIG_CRYPTO_ZLIB) += zlib.o
obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += michael_mic.o
obj-$(CONFIG_CRYPTO_CRC32C) += crc32c.o
obj-$(CONFIG_CRYPTO_CRC32) += crc32.o
-obj-$(CONFIG_CRYPTO_CRCT10DIF) += crct10dif.o
obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o authencesn.o
obj-$(CONFIG_CRYPTO_LZO) += lzo.o
+obj-$(CONFIG_CRYPTO_LZ4) += lz4.o
+obj-$(CONFIG_CRYPTO_LZ4HC) += lz4hc.o
obj-$(CONFIG_CRYPTO_842) += 842.o
obj-$(CONFIG_CRYPTO_RNG2) += rng.o
obj-$(CONFIG_CRYPTO_RNG2) += krng.o
diff --git a/crypto/crct10dif.c b/crypto/crct10dif.c
deleted file mode 100644
index 92aca96d6b9..00000000000
--- a/crypto/crct10dif.c
+++ /dev/null
@@ -1,178 +0,0 @@
-/*
- * Cryptographic API.
- *
- * T10 Data Integrity Field CRC16 Crypto Transform
- *
- * Copyright (c) 2007 Oracle Corporation. All rights reserved.
- * Written by Martin K. Petersen <martin.petersen@oracle.com>
- * Copyright (C) 2013 Intel Corporation
- * Author: Tim Chen <tim.c.chen@linux.intel.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
- * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
- * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- *
- */
-
-#include <linux/types.h>
-#include <linux/module.h>
-#include <linux/crc-t10dif.h>
-#include <crypto/internal/hash.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/kernel.h>
-
-struct chksum_desc_ctx {
- __u16 crc;
-};
-
-/* Table generated using the following polynomium:
- * x^16 + x^15 + x^11 + x^9 + x^8 + x^7 + x^5 + x^4 + x^2 + x + 1
- * gt: 0x8bb7
- */
-static const __u16 t10_dif_crc_table[256] = {
- 0x0000, 0x8BB7, 0x9CD9, 0x176E, 0xB205, 0x39B2, 0x2EDC, 0xA56B,
- 0xEFBD, 0x640A, 0x7364, 0xF8D3, 0x5DB8, 0xD60F, 0xC161, 0x4AD6,
- 0x54CD, 0xDF7A, 0xC814, 0x43A3, 0xE6C8, 0x6D7F, 0x7A11, 0xF1A6,
- 0xBB70, 0x30C7, 0x27A9, 0xAC1E, 0x0975, 0x82C2, 0x95AC, 0x1E1B,
- 0xA99A, 0x222D, 0x3543, 0xBEF4, 0x1B9F, 0x9028, 0x8746, 0x0CF1,
- 0x4627, 0xCD90, 0xDAFE, 0x5149, 0xF422, 0x7F95, 0x68FB, 0xE34C,
- 0xFD57, 0x76E0, 0x618E, 0xEA39, 0x4F52, 0xC4E5, 0xD38B, 0x583C,
- 0x12EA, 0x995D, 0x8E33, 0x0584, 0xA0EF, 0x2B58, 0x3C36, 0xB781,
- 0xD883, 0x5334, 0x445A, 0xCFED, 0x6A86, 0xE131, 0xF65F, 0x7DE8,
- 0x373E, 0xBC89, 0xABE7, 0x2050, 0x853B, 0x0E8C, 0x19E2, 0x9255,
- 0x8C4E, 0x07F9, 0x1097, 0x9B20, 0x3E4B, 0xB5FC, 0xA292, 0x2925,
- 0x63F3, 0xE844, 0xFF2A, 0x749D, 0xD1F6, 0x5A41, 0x4D2F, 0xC698,
- 0x7119, 0xFAAE, 0xEDC0, 0x6677, 0xC31C, 0x48AB, 0x5FC5, 0xD472,
- 0x9EA4, 0x1513, 0x027D, 0x89CA, 0x2CA1, 0xA716, 0xB078, 0x3BCF,
- 0x25D4, 0xAE63, 0xB90D, 0x32BA, 0x97D1, 0x1C66, 0x0B08, 0x80BF,
- 0xCA69, 0x41DE, 0x56B0, 0xDD07, 0x786C, 0xF3DB, 0xE4B5, 0x6F02,
- 0x3AB1, 0xB106, 0xA668, 0x2DDF, 0x88B4, 0x0303, 0x146D, 0x9FDA,
- 0xD50C, 0x5EBB, 0x49D5, 0xC262, 0x6709, 0xECBE, 0xFBD0, 0x7067,
- 0x6E7C, 0xE5CB, 0xF2A5, 0x7912, 0xDC79, 0x57CE, 0x40A0, 0xCB17,
- 0x81C1, 0x0A76, 0x1D18, 0x96AF, 0x33C4, 0xB873, 0xAF1D, 0x24AA,
- 0x932B, 0x189C, 0x0FF2, 0x8445, 0x212E, 0xAA99, 0xBDF7, 0x3640,
- 0x7C96, 0xF721, 0xE04F, 0x6BF8, 0xCE93, 0x4524, 0x524A, 0xD9FD,
- 0xC7E6, 0x4C51, 0x5B3F, 0xD088, 0x75E3, 0xFE54, 0xE93A, 0x628D,
- 0x285B, 0xA3EC, 0xB482, 0x3F35, 0x9A5E, 0x11E9, 0x0687, 0x8D30,
- 0xE232, 0x6985, 0x7EEB, 0xF55C, 0x5037, 0xDB80, 0xCCEE, 0x4759,
- 0x0D8F, 0x8638, 0x9156, 0x1AE1, 0xBF8A, 0x343D, 0x2353, 0xA8E4,
- 0xB6FF, 0x3D48, 0x2A26, 0xA191, 0x04FA, 0x8F4D, 0x9823, 0x1394,
- 0x5942, 0xD2F5, 0xC59B, 0x4E2C, 0xEB47, 0x60F0, 0x779E, 0xFC29,
- 0x4BA8, 0xC01F, 0xD771, 0x5CC6, 0xF9AD, 0x721A, 0x6574, 0xEEC3,
- 0xA415, 0x2FA2, 0x38CC, 0xB37B, 0x1610, 0x9DA7, 0x8AC9, 0x017E,
- 0x1F65, 0x94D2, 0x83BC, 0x080B, 0xAD60, 0x26D7, 0x31B9, 0xBA0E,
- 0xF0D8, 0x7B6F, 0x6C01, 0xE7B6, 0x42DD, 0xC96A, 0xDE04, 0x55B3
-};
-
-__u16 crc_t10dif_generic(__u16 crc, const unsigned char *buffer, size_t len)
-{
- unsigned int i;
-
- for (i = 0 ; i < len ; i++)
- crc = (crc << 8) ^ t10_dif_crc_table[((crc >> 8) ^ buffer[i]) & 0xff];
-
- return crc;
-}
-EXPORT_SYMBOL(crc_t10dif_generic);
-
-/*
- * Steps through buffer one byte at at time, calculates reflected
- * crc using table.
- */
-
-static int chksum_init(struct shash_desc *desc)
-{
- struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
-
- ctx->crc = 0;
-
- return 0;
-}
-
-static int chksum_update(struct shash_desc *desc, const u8 *data,
- unsigned int length)
-{
- struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
-
- ctx->crc = crc_t10dif_generic(ctx->crc, data, length);
- return 0;
-}
-
-static int chksum_final(struct shash_desc *desc, u8 *out)
-{
- struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
-
- *(__u16 *)out = ctx->crc;
- return 0;
-}
-
-static int __chksum_finup(__u16 *crcp, const u8 *data, unsigned int len,
- u8 *out)
-{
- *(__u16 *)out = crc_t10dif_generic(*crcp, data, len);
- return 0;
-}
-
-static int chksum_finup(struct shash_desc *desc, const u8 *data,
- unsigned int len, u8 *out)
-{
- struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
-
- return __chksum_finup(&ctx->crc, data, len, out);
-}
-
-static int chksum_digest(struct shash_desc *desc, const u8 *data,
- unsigned int length, u8 *out)
-{
- struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
-
- return __chksum_finup(&ctx->crc, data, length, out);
-}
-
-static struct shash_alg alg = {
- .digestsize = CRC_T10DIF_DIGEST_SIZE,
- .init = chksum_init,
- .update = chksum_update,
- .final = chksum_final,
- .finup = chksum_finup,
- .digest = chksum_digest,
- .descsize = sizeof(struct chksum_desc_ctx),
- .base = {
- .cra_name = "crct10dif",
- .cra_driver_name = "crct10dif-generic",
- .cra_priority = 100,
- .cra_blocksize = CRC_T10DIF_BLOCK_SIZE,
- .cra_module = THIS_MODULE,
- }
-};
-
-static int __init crct10dif_mod_init(void)
-{
- int ret;
-
- ret = crypto_register_shash(&alg);
- return ret;
-}
-
-static void __exit crct10dif_mod_fini(void)
-{
- crypto_unregister_shash(&alg);
-}
-
-module_init(crct10dif_mod_init);
-module_exit(crct10dif_mod_fini);
-
-MODULE_AUTHOR("Tim Chen <tim.c.chen@linux.intel.com>");
-MODULE_DESCRIPTION("T10 DIF CRC calculation.");
-MODULE_LICENSE("GPL");
diff --git a/crypto/lz4.c b/crypto/lz4.c
new file mode 100644
index 00000000000..4586dd15b0d
--- /dev/null
+++ b/crypto/lz4.c
@@ -0,0 +1,106 @@
+/*
+ * Cryptographic API.
+ *
+ * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 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
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/vmalloc.h>
+#include <linux/lz4.h>
+
+struct lz4_ctx {
+ void *lz4_comp_mem;
+};
+
+static int lz4_init(struct crypto_tfm *tfm)
+{
+ struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ ctx->lz4_comp_mem = vmalloc(LZ4_MEM_COMPRESS);
+ if (!ctx->lz4_comp_mem)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void lz4_exit(struct crypto_tfm *tfm)
+{
+ struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
+ vfree(ctx->lz4_comp_mem);
+}
+
+static int lz4_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
+ size_t tmp_len = *dlen;
+ int err;
+
+ err = lz4_compress(src, slen, dst, &tmp_len, ctx->lz4_comp_mem);
+
+ if (err < 0)
+ return -EINVAL;
+
+ *dlen = tmp_len;
+ return 0;
+}
+
+static int lz4_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ int err;
+ size_t tmp_len = *dlen;
+ size_t __slen = slen;
+
+ err = lz4_decompress(src, &__slen, dst, tmp_len);
+ if (err < 0)
+ return -EINVAL;
+
+ *dlen = tmp_len;
+ return err;
+}
+
+static struct crypto_alg alg_lz4 = {
+ .cra_name = "lz4",
+ .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
+ .cra_ctxsize = sizeof(struct lz4_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(alg_lz4.cra_list),
+ .cra_init = lz4_init,
+ .cra_exit = lz4_exit,
+ .cra_u = { .compress = {
+ .coa_compress = lz4_compress_crypto,
+ .coa_decompress = lz4_decompress_crypto } }
+};
+
+static int __init lz4_mod_init(void)
+{
+ return crypto_register_alg(&alg_lz4);
+}
+
+static void __exit lz4_mod_fini(void)
+{
+ crypto_unregister_alg(&alg_lz4);
+}
+
+module_init(lz4_mod_init);
+module_exit(lz4_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZ4 Compression Algorithm");
diff --git a/crypto/lz4hc.c b/crypto/lz4hc.c
new file mode 100644
index 00000000000..151ba31d34e
--- /dev/null
+++ b/crypto/lz4hc.c
@@ -0,0 +1,106 @@
+/*
+ * Cryptographic API.
+ *
+ * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 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
+ *
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/vmalloc.h>
+#include <linux/lz4.h>
+
+struct lz4hc_ctx {
+ void *lz4hc_comp_mem;
+};
+
+static int lz4hc_init(struct crypto_tfm *tfm)
+{
+ struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ ctx->lz4hc_comp_mem = vmalloc(LZ4HC_MEM_COMPRESS);
+ if (!ctx->lz4hc_comp_mem)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void lz4hc_exit(struct crypto_tfm *tfm)
+{
+ struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ vfree(ctx->lz4hc_comp_mem);
+}
+
+static int lz4hc_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
+ size_t tmp_len = *dlen;
+ int err;
+
+ err = lz4hc_compress(src, slen, dst, &tmp_len, ctx->lz4hc_comp_mem);
+
+ if (err < 0)
+ return -EINVAL;
+
+ *dlen = tmp_len;
+ return 0;
+}
+
+static int lz4hc_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ int err;
+ size_t tmp_len = *dlen;
+ size_t __slen = slen;
+
+ err = lz4_decompress(src, &__slen, dst, tmp_len);
+ if (err < 0)
+ return -EINVAL;
+
+ *dlen = tmp_len;
+ return err;
+}
+
+static struct crypto_alg alg_lz4hc = {
+ .cra_name = "lz4hc",
+ .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
+ .cra_ctxsize = sizeof(struct lz4hc_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(alg_lz4hc.cra_list),
+ .cra_init = lz4hc_init,
+ .cra_exit = lz4hc_exit,
+ .cra_u = { .compress = {
+ .coa_compress = lz4hc_compress_crypto,
+ .coa_decompress = lz4hc_decompress_crypto } }
+};
+
+static int __init lz4hc_mod_init(void)
+{
+ return crypto_register_alg(&alg_lz4hc);
+}
+
+static void __exit lz4hc_mod_fini(void)
+{
+ crypto_unregister_alg(&alg_lz4hc);
+}
+
+module_init(lz4hc_mod_init);
+module_exit(lz4hc_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZ4HC Compression Algorithm");
diff --git a/crypto/tcrypt.c b/crypto/tcrypt.c
index 25a5934f0e5..66d254ce0d1 100644
--- a/crypto/tcrypt.c
+++ b/crypto/tcrypt.c
@@ -1174,10 +1174,6 @@ static int do_test(int m)
ret += tcrypt_test("ghash");
break;
- case 47:
- ret += tcrypt_test("crct10dif");
- break;
-
case 100:
ret += tcrypt_test("hmac(md5)");
break;
@@ -1502,10 +1498,6 @@ static int do_test(int m)
test_hash_speed("crc32c", sec, generic_hash_speed_template);
if (mode > 300 && mode < 400) break;
- case 320:
- test_hash_speed("crct10dif", sec, generic_hash_speed_template);
- if (mode > 300 && mode < 400) break;
-
case 399:
break;
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index e091ef6e179..b7bc2e70895 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -2046,16 +2046,6 @@ static const struct alg_test_desc alg_test_descs[] = {
}
}
}, {
- .alg = "crct10dif",
- .test = alg_test_hash,
- .fips_allowed = 1,
- .suite = {
- .hash = {
- .vecs = crct10dif_tv_template,
- .count = CRCT10DIF_TEST_VECTORS
- }
- }
- }, {
.alg = "cryptd(__driver-cbc-aes-aesni)",
.test = alg_test_null,
.fips_allowed = 1,
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 7d44aa3d6b4..1e701bc075b 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -450,39 +450,6 @@ static struct hash_testvec rmd320_tv_template[] = {
}
};
-#define CRCT10DIF_TEST_VECTORS 3
-static struct hash_testvec crct10dif_tv_template[] = {
- {
- .plaintext = "abc",
- .psize = 3,
-#ifdef __LITTLE_ENDIAN
- .digest = "\x3b\x44",
-#else
- .digest = "\x44\x3b",
-#endif
- }, {
- .plaintext = "1234567890123456789012345678901234567890"
- "123456789012345678901234567890123456789",
- .psize = 79,
-#ifdef __LITTLE_ENDIAN
- .digest = "\x70\x4b",
-#else
- .digest = "\x4b\x70",
-#endif
- }, {
- .plaintext =
- "abcddddddddddddddddddddddddddddddddddddddddddddddddddddd",
- .psize = 56,
-#ifdef __LITTLE_ENDIAN
- .digest = "\xe3\x9c",
-#else
- .digest = "\x9c\xe3",
-#endif
- .np = 2,
- .tap = { 28, 28 }
- }
-};
-
/*
* SHA1 test vectors from from FIPS PUB 180-1
* Long vector from CAVS 5.0