// SPDX-License-Identifier: GPL-2.0-or-later/* * Cryptographic API. * * Null algorithms, aka Much Ado About Nothing. * * These are needed for IPsec, and may be useful in general for * testing & debugging. * * The null cipher is compliant with RFC2410. * * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> */ #include <crypto/null.h>#include <crypto/internal/hash.h>#include <crypto/internal/skcipher.h>#include <crypto/scatterwalk.h>#include <linux/init.h>#include <linux/module.h>#include <linux/string.h> static int null_init(struct shash_desc *desc){	return 0;} static int null_update(struct shash_desc *desc, const u8 *data,		       unsigned int len){	return 0;} static int null_final(struct shash_desc *desc, u8 *out){	return 0;} static int null_digest(struct shash_desc *desc, const u8 *data,		       unsigned int len, u8 *out){	return 0;} static int null_hash_setkey(struct crypto_shash *tfm, const u8 *key,			    unsigned int keylen){ return 0; } static int null_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,				unsigned int keylen){ return 0; } static int null_skcipher_crypt(struct skcipher_request *req){	if (req->src != req->dst)		memcpy_sglist(req->dst, req->src, req->cryptlen);	return 0;} static struct shash_alg digest_null = {	.digestsize		=	NULL_DIGEST_SIZE,	.setkey   		=	null_hash_setkey,	.init   		=	null_init,	.update 		=	null_update,	.finup 			=	null_digest,	.digest 		=	null_digest,	.final  		=	null_final,	.base			=	{		.cra_name		=	"digest_null",		.cra_driver_name	=	"digest_null-generic",		.cra_blocksize		=	NULL_BLOCK_SIZE,		.cra_module		=	THIS_MODULE,	}}; static struct skcipher_alg skcipher_null = {	.base.cra_name		=	"ecb(cipher_null)",	.base.cra_driver_name	=	"ecb-cipher_null",	.base.cra_priority	=	100,	.base.cra_blocksize	=	NULL_BLOCK_SIZE,	.base.cra_ctxsize	=	0,	.base.cra_module	=	THIS_MODULE,	.min_keysize		=	NULL_KEY_SIZE,	.max_keysize		=	NULL_KEY_SIZE,	.ivsize			=	NULL_IV_SIZE,	.setkey			=	null_skcipher_setkey,	.encrypt		=	null_skcipher_crypt,	.decrypt		=	null_skcipher_crypt,}; MODULE_ALIAS_CRYPTO("digest_null");MODULE_ALIAS_CRYPTO("ecb(cipher_null)"); static int __init crypto_null_mod_init(void){	int ret = 0; 	ret = crypto_register_shash(&digest_null);	if (ret < 0)		goto out; 	ret = crypto_register_skcipher(&skcipher_null);	if (ret < 0)		goto out_unregister_shash; 	return 0; out_unregister_shash:	crypto_unregister_shash(&digest_null);out:	return ret;} static void __exit crypto_null_mod_fini(void){	crypto_unregister_shash(&digest_null);	crypto_unregister_skcipher(&skcipher_null);} module_init(crypto_null_mod_init);module_exit(crypto_null_mod_fini); MODULE_LICENSE("GPL");MODULE_DESCRIPTION("Null Cryptographic Algorithms");