// SPDX-License-Identifier: GPL-2.0-only/* * Copyright 2012 Xyratex Technology Limited */ /* * This is crypto api shash wrappers to crc32_le. */ #include <linux/unaligned.h>#include <linux/crc32.h>#include <crypto/internal/hash.h>#include <linux/init.h>#include <linux/module.h>#include <linux/string.h>#include <linux/kernel.h> #define CHKSUM_BLOCK_SIZE	1#define CHKSUM_DIGEST_SIZE	4 /** No default init with ~0 */static int crc32_cra_init(struct crypto_tfm *tfm){	u32 *key = crypto_tfm_ctx(tfm); 	*key = 0; 	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 crc32_setkey(struct crypto_shash *hash, const u8 *key,			unsigned int keylen){	u32 *mctx = crypto_shash_ctx(hash); 	if (keylen != sizeof(u32))		return -EINVAL;	*mctx = get_unaligned_le32(key);	return 0;} static int crc32_init(struct shash_desc *desc){	u32 *mctx = crypto_shash_ctx(desc->tfm);	u32 *crcp = shash_desc_ctx(desc); 	*crcp = *mctx; 	return 0;} static int crc32_update(struct shash_desc *desc, const u8 *data,			unsigned int len){	u32 *crcp = shash_desc_ctx(desc); 	*crcp = crc32_le(*crcp, data, len);	return 0;} /* No final XOR 0xFFFFFFFF, like crc32_le */static int __crc32_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *out){	put_unaligned_le32(crc32_le(*crcp, data, len), out);	return 0;} static int crc32_finup(struct shash_desc *desc, const u8 *data,		       unsigned int len, u8 *out){	return __crc32_finup(shash_desc_ctx(desc), data, len, out);} static int crc32_final(struct shash_desc *desc, u8 *out){	u32 *crcp = shash_desc_ctx(desc); 	put_unaligned_le32(*crcp, out);	return 0;} static int crc32_digest(struct shash_desc *desc, const u8 *data,			unsigned int len, u8 *out){	return __crc32_finup(crypto_shash_ctx(desc->tfm), data, len, out);} static struct shash_alg alg = {	.setkey			= crc32_setkey,	.init			= crc32_init,	.update			= crc32_update,	.final			= crc32_final,	.finup			= crc32_finup,	.digest			= crc32_digest,	.descsize		= sizeof(u32),	.digestsize		= CHKSUM_DIGEST_SIZE, 	.base.cra_name		= "crc32",	.base.cra_driver_name	= "crc32-lib",	.base.cra_priority	= 100,	.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,	.base.cra_blocksize	= CHKSUM_BLOCK_SIZE,	.base.cra_ctxsize	= sizeof(u32),	.base.cra_module	= THIS_MODULE,	.base.cra_init		= crc32_cra_init,}; static int __init crc32_mod_init(void){	return crypto_register_shash(&alg);} static void __exit crc32_mod_fini(void){	crypto_unregister_shash(&alg);} module_init(crc32_mod_init);module_exit(crc32_mod_fini); MODULE_AUTHOR("Alexander Boyko <alexander_boyko@xyratex.com>");MODULE_DESCRIPTION("CRC32 calculations wrapper for lib/crc32");MODULE_LICENSE("GPL");MODULE_ALIAS_CRYPTO("crc32");