1 // SPDX-License-Identifier: GPL-2.0 2 3 /* 4 * SM4 Cipher Algorithm. 5 * 6 * Copyright (C) 2018 ARM Limited or its affiliates. 7 * All rights reserved. 8 */ 9 10 #include <crypto/sm4.h> 11 #include <linux/module.h> 12 #include <linux/init.h> 13 #include <linux/types.h> 14 #include <linux/errno.h> 15 #include <linux/crypto.h> 16 #include <asm/byteorder.h> 17 #include <asm/unaligned.h> 18 19 /** 20 * sm4_setkey - Set the SM4 key. 21 * @tfm: The %crypto_tfm that is used in the context. 22 * @in_key: The input key. 23 * @key_len: The size of the key. 24 * 25 * This function uses sm4_expandkey() to expand the key. 26 * &sm4_ctx _must_ be the private data embedded in @tfm which is 27 * retrieved with crypto_tfm_ctx(). 28 * 29 * Return: 0 on success; -EINVAL on failure (only happens for bad key lengths) 30 */ 31 static int sm4_setkey(struct crypto_tfm *tfm, const u8 *in_key, 32 unsigned int key_len) 33 { 34 struct sm4_ctx *ctx = crypto_tfm_ctx(tfm); 35 36 return sm4_expandkey(ctx, in_key, key_len); 37 } 38 39 /* encrypt a block of text */ 40 41 static void sm4_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 42 { 43 const struct sm4_ctx *ctx = crypto_tfm_ctx(tfm); 44 45 sm4_crypt_block(ctx->rkey_enc, out, in); 46 } 47 48 /* decrypt a block of text */ 49 50 static void sm4_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) 51 { 52 const struct sm4_ctx *ctx = crypto_tfm_ctx(tfm); 53 54 sm4_crypt_block(ctx->rkey_dec, out, in); 55 } 56 57 static struct crypto_alg sm4_alg = { 58 .cra_name = "sm4", 59 .cra_driver_name = "sm4-generic", 60 .cra_priority = 100, 61 .cra_flags = CRYPTO_ALG_TYPE_CIPHER, 62 .cra_blocksize = SM4_BLOCK_SIZE, 63 .cra_ctxsize = sizeof(struct sm4_ctx), 64 .cra_module = THIS_MODULE, 65 .cra_u = { 66 .cipher = { 67 .cia_min_keysize = SM4_KEY_SIZE, 68 .cia_max_keysize = SM4_KEY_SIZE, 69 .cia_setkey = sm4_setkey, 70 .cia_encrypt = sm4_encrypt, 71 .cia_decrypt = sm4_decrypt 72 } 73 } 74 }; 75 76 static int __init sm4_init(void) 77 { 78 return crypto_register_alg(&sm4_alg); 79 } 80 81 static void __exit sm4_fini(void) 82 { 83 crypto_unregister_alg(&sm4_alg); 84 } 85 86 subsys_initcall(sm4_init); 87 module_exit(sm4_fini); 88 89 MODULE_DESCRIPTION("SM4 Cipher Algorithm"); 90 MODULE_LICENSE("GPL v2"); 91 MODULE_ALIAS_CRYPTO("sm4"); 92 MODULE_ALIAS_CRYPTO("sm4-generic"); 93