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Release 4.14 arch/x86/crypto/crc32-pclmul_glue.c

Directory: arch/x86/crypto
/* GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * 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 version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see http://www.gnu.org/licenses
 *
 * Please  visit http://www.xyratex.com/contact if you need additional
 * information or have any questions.
 *
 * GPL HEADER END
 */

/*
 * Copyright 2012 Xyratex Technology Limited
 *
 * Wrappers for kernel crypto shash api to pclmulqdq crc32 imlementation.
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/crc32.h>
#include <crypto/internal/hash.h>

#include <asm/cpufeatures.h>
#include <asm/cpu_device_id.h>
#include <asm/fpu/api.h>


#define CHKSUM_BLOCK_SIZE	1

#define CHKSUM_DIGEST_SIZE	4


#define PCLMUL_MIN_LEN		64L     
/* minimum size of buffer
                                         * for crc32_pclmul_le_16 */

#define SCALE_F			16L	
/* size of xmm register */

#define SCALE_F_MASK		(SCALE_F - 1)

u32 crc32_pclmul_le_16(unsigned char const *buffer, size_t len, u32 crc32);

static u32 __attribute__((pure))
	
crc32_pclmul_le(u32 crc, unsigned char const *p, size_t len)
{
	unsigned int iquotient;
	unsigned int iremainder;
	unsigned int prealign;

	if (len < PCLMUL_MIN_LEN + SCALE_F_MASK || !irq_fpu_usable())
		return crc32_le(crc, p, len);

	if ((long)p & SCALE_F_MASK) {
		/* align p to 16 byte */
		prealign = SCALE_F - ((long)p & SCALE_F_MASK);

		crc = crc32_le(crc, p, prealign);
		len -= prealign;
		p = (unsigned char *)(((unsigned long)p + SCALE_F_MASK) &
				     ~SCALE_F_MASK);
	}
	iquotient = len & (~SCALE_F_MASK);
	iremainder = len & SCALE_F_MASK;

	kernel_fpu_begin();
	crc = crc32_pclmul_le_16(p, iquotient, crc);
	kernel_fpu_end();

	if (iremainder)
		crc = crc32_le(crc, p + iquotient, iremainder);

	return crc;
}


static int crc32_pclmul_cra_init(struct crypto_tfm *tfm) { u32 *key = crypto_tfm_ctx(tfm); *key = 0; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko28100.00%1100.00%
Total28100.00%1100.00%


static int crc32_pclmul_setkey(struct crypto_shash *hash, const u8 *key, unsigned int keylen) { u32 *mctx = crypto_shash_ctx(hash); if (keylen != sizeof(u32)) { crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN); return -EINVAL; } *mctx = le32_to_cpup((__le32 *)key); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko66100.00%1100.00%
Total66100.00%1100.00%


static int crc32_pclmul_init(struct shash_desc *desc) { u32 *mctx = crypto_shash_ctx(desc->tfm); u32 *crcp = shash_desc_ctx(desc); *crcp = *mctx; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko40100.00%1100.00%
Total40100.00%1100.00%


static int crc32_pclmul_update(struct shash_desc *desc, const u8 *data, unsigned int len) { u32 *crcp = shash_desc_ctx(desc); *crcp = crc32_pclmul_le(*crcp, data, len); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko45100.00%1100.00%
Total45100.00%1100.00%

/* No final XOR 0xFFFFFFFF, like crc32_le */
static int __crc32_pclmul_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *out) { *(__le32 *)out = cpu_to_le32(crc32_pclmul_le(*crcp, data, len)); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko46100.00%1100.00%
Total46100.00%1100.00%


static int crc32_pclmul_finup(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out) { return __crc32_pclmul_finup(shash_desc_ctx(desc), data, len, out); }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko39100.00%1100.00%
Total39100.00%1100.00%


static int crc32_pclmul_final(struct shash_desc *desc, u8 *out) { u32 *crcp = shash_desc_ctx(desc); *(__le32 *)out = cpu_to_le32p(crcp); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko39100.00%1100.00%
Total39100.00%1100.00%


static int crc32_pclmul_digest(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out) { return __crc32_pclmul_finup(crypto_shash_ctx(desc->tfm), data, len, out); }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko41100.00%1100.00%
Total41100.00%1100.00%

static struct shash_alg alg = { .setkey = crc32_pclmul_setkey, .init = crc32_pclmul_init, .update = crc32_pclmul_update, .final = crc32_pclmul_final, .finup = crc32_pclmul_finup, .digest = crc32_pclmul_digest, .descsize = sizeof(u32), .digestsize = CHKSUM_DIGEST_SIZE, .base = { .cra_name = "crc32", .cra_driver_name = "crc32-pclmul", .cra_priority = 200, .cra_blocksize = CHKSUM_BLOCK_SIZE, .cra_ctxsize = sizeof(u32), .cra_module = THIS_MODULE, .cra_init = crc32_pclmul_cra_init, } }; static const struct x86_cpu_id crc32pclmul_cpu_id[] = { X86_FEATURE_MATCH(X86_FEATURE_PCLMULQDQ), {} }; MODULE_DEVICE_TABLE(x86cpu, crc32pclmul_cpu_id);
static int __init crc32_pclmul_mod_init(void) { if (!x86_match_cpu(crc32pclmul_cpu_id)) { pr_info("PCLMULQDQ-NI instructions are not detected.\n"); return -ENODEV; } return crypto_register_shash(&alg); }

Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko35100.00%1100.00%
Total35100.00%1100.00%


static void __exit crc32_pclmul_mod_fini(void) { crypto_unregister_shash(&alg); }

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PersonTokensPropCommitsCommitProp
Alexander Boyko15100.00%1100.00%
Total15100.00%1100.00%

module_init(crc32_pclmul_mod_init); module_exit(crc32_pclmul_mod_fini); MODULE_AUTHOR("Alexander Boyko <alexander_boyko@xyratex.com>"); MODULE_LICENSE("GPL"); MODULE_ALIAS_CRYPTO("crc32"); MODULE_ALIAS_CRYPTO("crc32-pclmul");

Overall Contributors

PersonTokensPropCommitsCommitProp
Alexander Boyko77699.49%125.00%
Kees Cook20.26%125.00%
Ingo Molnar10.13%125.00%
Borislav Petkov10.13%125.00%
Total780100.00%4100.00%
Directory: arch/x86/crypto
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