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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-03 09:28:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-03 09:28:16 -0700
commitce945bb935ddd4a72cc49c11e755dea2de7a81c9 (patch)
treec204dd2fda16e95058e86a029b30389b5840db53 /crypto/crc32c_generic.c
parent46932cc3784fab58cedfed099127f243e7af9102 (diff)
parent6ebc73cd0ab4ff5094258b5057ba4b678d664619 (diff)
downloadlinux-crypto-ce945bb935ddd4a72cc49c11e755dea2de7a81c9.tar.gz
linux-crypto-ce945bb935ddd4a72cc49c11e755dea2de7a81c9.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "Here is the crypto update for 3.15: - Added 3DES driver for OMAP4/AM43xx - Added AVX2 acceleration for SHA - Added hash-only AEAD algorithms in caam - Removed tegra driver as it is not functioning and the hardware is too slow - Allow blkcipher walks over AEAD (needed for ARM) - Fixed unprotected FPU/SSE access in ghash-clmulni-intel - Fixed highmem crash in omap-sham - Add (zero entropy) randomness when initialising hardware RNGs - Fixed unaligned ahash comletion functions - Added soft module depedency for crc32c for initrds that use crc32c" * git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (60 commits) crypto: ghash-clmulni-intel - use C implementation for setkey() crypto: x86/sha1 - reduce size of the AVX2 asm implementation crypto: x86/sha1 - fix stack alignment of AVX2 variant crypto: x86/sha1 - re-enable the AVX variant crypto: sha - SHA1 transform x86_64 AVX2 crypto: crypto_wq - Fix late crypto work queue initialization crypto: caam - add missing key_dma unmap crypto: caam - add support for aead null encryption crypto: testmgr - add aead null encryption test vectors crypto: export NULL algorithms defines crypto: caam - remove error propagation handling crypto: hash - Simplify the ahash_finup implementation crypto: hash - Pull out the functions to save/restore request crypto: hash - Fix the pointer voodoo in unaligned ahash crypto: caam - Fix first parameter to caam_init_rng crypto: omap-sham - Map SG pages if they are HIGHMEM before accessing crypto: caam - Dynamic memory allocation for caam_rng_ctx object crypto: allow blkcipher walks over AEAD data crypto: remove direct blkcipher_walk dependency on transform hwrng: add randomness to system from rng sources ...
Diffstat (limited to 'crypto/crc32c_generic.c')
-rw-r--r--crypto/crc32c_generic.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/crypto/crc32c_generic.c b/crypto/crc32c_generic.c
new file mode 100644
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--- /dev/null
+++ b/crypto/crc32c_generic.c
@@ -0,0 +1,174 @@
+/*
+ * Cryptographic API.
+ *
+ * CRC32C chksum
+ *
+ *@Article{castagnoli-crc,
+ * author = { Guy Castagnoli and Stefan Braeuer and Martin Herrman},
+ * title = {{Optimization of Cyclic Redundancy-Check Codes with 24
+ * and 32 Parity Bits}},
+ * journal = IEEE Transactions on Communication,
+ * year = {1993},
+ * volume = {41},
+ * number = {6},
+ * pages = {},
+ * month = {June},
+ *}
+ * Used by the iSCSI driver, possibly others, and derived from the
+ * the iscsi-crc.c module of the linux-iscsi driver at
+ * http://linux-iscsi.sourceforge.net.
+ *
+ * Following the example of lib/crc32, this function is intended to be
+ * flexible and useful for all users. Modules that currently have their
+ * own crc32c, but hopefully may be able to use this one are:
+ * net/sctp (please add all your doco to here if you change to
+ * use this one!)
+ * <endoflist>
+ *
+ * Copyright (c) 2004 Cisco Systems, Inc.
+ * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * 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.
+ *
+ */
+
+#include <crypto/internal/hash.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/crc32.h>
+
+#define CHKSUM_BLOCK_SIZE 1
+#define CHKSUM_DIGEST_SIZE 4
+
+struct chksum_ctx {
+ u32 key;
+};
+
+struct chksum_desc_ctx {
+ u32 crc;
+};
+
+/*
+ * Steps through buffer one byte at at time, calculates reflected
+ * crc using table.
+ */
+
+static int chksum_init(struct shash_desc *desc)
+{
+ struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
+ struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
+
+ ctx->crc = mctx->key;
+
+ return 0;
+}
+
+/*
+ * Setting the seed allows arbitrary accumulators and flexible XOR policy
+ * If your algorithm starts with ~0, then XOR with ~0 before you set
+ * the seed.
+ */
+static int chksum_setkey(struct crypto_shash *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct chksum_ctx *mctx = crypto_shash_ctx(tfm);
+
+ if (keylen != sizeof(mctx->key)) {
+ crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+ mctx->key = le32_to_cpu(*(__le32 *)key);
+ 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 = __crc32c_le(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);
+
+ *(__le32 *)out = ~cpu_to_le32p(&ctx->crc);
+ return 0;
+}
+
+static int __chksum_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *out)
+{
+ *(__le32 *)out = ~cpu_to_le32(__crc32c_le(*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_ctx *mctx = crypto_shash_ctx(desc->tfm);
+
+ return __chksum_finup(&mctx->key, data, length, out);
+}
+
+static int crc32c_cra_init(struct crypto_tfm *tfm)
+{
+ struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
+
+ mctx->key = ~0;
+ return 0;
+}
+
+static struct shash_alg alg = {
+ .digestsize = CHKSUM_DIGEST_SIZE,
+ .setkey = chksum_setkey,
+ .init = chksum_init,
+ .update = chksum_update,
+ .final = chksum_final,
+ .finup = chksum_finup,
+ .digest = chksum_digest,
+ .descsize = sizeof(struct chksum_desc_ctx),
+ .base = {
+ .cra_name = "crc32c",
+ .cra_driver_name = "crc32c-generic",
+ .cra_priority = 100,
+ .cra_blocksize = CHKSUM_BLOCK_SIZE,
+ .cra_alignmask = 3,
+ .cra_ctxsize = sizeof(struct chksum_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = crc32c_cra_init,
+ }
+};
+
+static int __init crc32c_mod_init(void)
+{
+ return crypto_register_shash(&alg);
+}
+
+static void __exit crc32c_mod_fini(void)
+{
+ crypto_unregister_shash(&alg);
+}
+
+module_init(crc32c_mod_init);
+module_exit(crc32c_mod_fini);
+
+MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>");
+MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations wrapper for lib/crc32c");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("crc32c");
+MODULE_SOFTDEP("pre: crc32c");