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Diffstat (limited to 'crypto/sm4_generic.c')
| -rw-r--r-- | crypto/sm4_generic.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/crypto/sm4_generic.c b/crypto/sm4_generic.c new file mode 100644 index 000000000..c18eebfd5 --- /dev/null +++ b/crypto/sm4_generic.c @@ -0,0 +1,246 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * SM4 Cipher Algorithm. + * + * Copyright (C) 2018 ARM Limited or its affiliates. + * All rights reserved. + */ + +#include <crypto/sm4.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/crypto.h> +#include <asm/byteorder.h> +#include <asm/unaligned.h> + +static const u32 fk[4] = { + 0xa3b1bac6, 0x56aa3350, 0x677d9197, 0xb27022dc +}; + +static const u8 sbox[256] = { + 0xd6, 0x90, 0xe9, 0xfe, 0xcc, 0xe1, 0x3d, 0xb7, + 0x16, 0xb6, 0x14, 0xc2, 0x28, 0xfb, 0x2c, 0x05, + 0x2b, 0x67, 0x9a, 0x76, 0x2a, 0xbe, 0x04, 0xc3, + 0xaa, 0x44, 0x13, 0x26, 0x49, 0x86, 0x06, 0x99, + 0x9c, 0x42, 0x50, 0xf4, 0x91, 0xef, 0x98, 0x7a, + 0x33, 0x54, 0x0b, 0x43, 0xed, 0xcf, 0xac, 0x62, + 0xe4, 0xb3, 0x1c, 0xa9, 0xc9, 0x08, 0xe8, 0x95, + 0x80, 0xdf, 0x94, 0xfa, 0x75, 0x8f, 0x3f, 0xa6, + 0x47, 0x07, 0xa7, 0xfc, 0xf3, 0x73, 0x17, 0xba, + 0x83, 0x59, 0x3c, 0x19, 0xe6, 0x85, 0x4f, 0xa8, + 0x68, 0x6b, 0x81, 0xb2, 0x71, 0x64, 0xda, 0x8b, + 0xf8, 0xeb, 0x0f, 0x4b, 0x70, 0x56, 0x9d, 0x35, + 0x1e, 0x24, 0x0e, 0x5e, 0x63, 0x58, 0xd1, 0xa2, + 0x25, 0x22, 0x7c, 0x3b, 0x01, 0x21, 0x78, 0x87, + 0xd4, 0x00, 0x46, 0x57, 0x9f, 0xd3, 0x27, 0x52, + 0x4c, 0x36, 0x02, 0xe7, 0xa0, 0xc4, 0xc8, 0x9e, + 0xea, 0xbf, 0x8a, 0xd2, 0x40, 0xc7, 0x38, 0xb5, + 0xa3, 0xf7, 0xf2, 0xce, 0xf9, 0x61, 0x15, 0xa1, + 0xe0, 0xae, 0x5d, 0xa4, 0x9b, 0x34, 0x1a, 0x55, + 0xad, 0x93, 0x32, 0x30, 0xf5, 0x8c, 0xb1, 0xe3, + 0x1d, 0xf6, 0xe2, 0x2e, 0x82, 0x66, 0xca, 0x60, + 0xc0, 0x29, 0x23, 0xab, 0x0d, 0x53, 0x4e, 0x6f, + 0xd5, 0xdb, 0x37, 0x45, 0xde, 0xfd, 0x8e, 0x2f, + 0x03, 0xff, 0x6a, 0x72, 0x6d, 0x6c, 0x5b, 0x51, + 0x8d, 0x1b, 0xaf, 0x92, 0xbb, 0xdd, 0xbc, 0x7f, + 0x11, 0xd9, 0x5c, 0x41, 0x1f, 0x10, 0x5a, 0xd8, + 0x0a, 0xc1, 0x31, 0x88, 0xa5, 0xcd, 0x7b, 0xbd, + 0x2d, 0x74, 0xd0, 0x12, 0xb8, 0xe5, 0xb4, 0xb0, + 0x89, 0x69, 0x97, 0x4a, 0x0c, 0x96, 0x77, 0x7e, + 0x65, 0xb9, 0xf1, 0x09, 0xc5, 0x6e, 0xc6, 0x84, + 0x18, 0xf0, 0x7d, 0xec, 0x3a, 0xdc, 0x4d, 0x20, + 0x79, 0xee, 0x5f, 0x3e, 0xd7, 0xcb, 0x39, 0x48 +}; + +static const u32 ck[] = { + 0x00070e15, 0x1c232a31, 0x383f464d, 0x545b6269, + 0x70777e85, 0x8c939aa1, 0xa8afb6bd, 0xc4cbd2d9, + 0xe0e7eef5, 0xfc030a11, 0x181f262d, 0x343b4249, + 0x50575e65, 0x6c737a81, 0x888f969d, 0xa4abb2b9, + 0xc0c7ced5, 0xdce3eaf1, 0xf8ff060d, 0x141b2229, + 0x30373e45, 0x4c535a61, 0x686f767d, 0x848b9299, + 0xa0a7aeb5, 0xbcc3cad1, 0xd8dfe6ed, 0xf4fb0209, + 0x10171e25, 0x2c333a41, 0x484f565d, 0x646b7279 +}; + +static u32 sm4_t_non_lin_sub(u32 x) +{ + int i; + u8 *b = (u8 *)&x; + + for (i = 0; i < 4; ++i) + b[i] = sbox[b[i]]; + + return x; +} + +static u32 sm4_key_lin_sub(u32 x) +{ + return x ^ rol32(x, 13) ^ rol32(x, 23); + +} + +static u32 sm4_enc_lin_sub(u32 x) +{ + return x ^ rol32(x, 2) ^ rol32(x, 10) ^ rol32(x, 18) ^ rol32(x, 24); +} + +static u32 sm4_key_sub(u32 x) +{ + return sm4_key_lin_sub(sm4_t_non_lin_sub(x)); +} + +static u32 sm4_enc_sub(u32 x) +{ + return sm4_enc_lin_sub(sm4_t_non_lin_sub(x)); +} + +static u32 sm4_round(const u32 *x, const u32 rk) +{ + return x[0] ^ sm4_enc_sub(x[1] ^ x[2] ^ x[3] ^ rk); +} + + +/** + * crypto_sm4_expand_key - Expands the SM4 key as described in GB/T 32907-2016 + * @ctx: The location where the computed key will be stored. + * @in_key: The supplied key. + * @key_len: The length of the supplied key. + * + * Returns 0 on success. The function fails only if an invalid key size (or + * pointer) is supplied. + */ +int crypto_sm4_expand_key(struct crypto_sm4_ctx *ctx, const u8 *in_key, + unsigned int key_len) +{ + u32 rk[4], t; + const u32 *key = (u32 *)in_key; + int i; + + if (key_len != SM4_KEY_SIZE) + return -EINVAL; + + for (i = 0; i < 4; ++i) + rk[i] = get_unaligned_be32(&key[i]) ^ fk[i]; + + for (i = 0; i < 32; ++i) { + t = rk[0] ^ sm4_key_sub(rk[1] ^ rk[2] ^ rk[3] ^ ck[i]); + ctx->rkey_enc[i] = t; + rk[0] = rk[1]; + rk[1] = rk[2]; + rk[2] = rk[3]; + rk[3] = t; + } + + for (i = 0; i < 32; ++i) + ctx->rkey_dec[i] = ctx->rkey_enc[31 - i]; + + return 0; +} +EXPORT_SYMBOL_GPL(crypto_sm4_expand_key); + +/** + * crypto_sm4_set_key - Set the AES key. + * @tfm: The %crypto_tfm that is used in the context. + * @in_key: The input key. + * @key_len: The size of the key. + * + * Returns 0 on success, on failure the %CRYPTO_TFM_RES_BAD_KEY_LEN flag in tfm + * is set. The function uses crypto_sm4_expand_key() to expand the key. + * &crypto_sm4_ctx _must_ be the private data embedded in @tfm which is + * retrieved with crypto_tfm_ctx(). + */ +int crypto_sm4_set_key(struct crypto_tfm *tfm, const u8 *in_key, + unsigned int key_len) +{ + struct crypto_sm4_ctx *ctx = crypto_tfm_ctx(tfm); + u32 *flags = &tfm->crt_flags; + int ret; + + ret = crypto_sm4_expand_key(ctx, in_key, key_len); + if (!ret) + return 0; + + *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; + return -EINVAL; +} +EXPORT_SYMBOL_GPL(crypto_sm4_set_key); + +static void sm4_do_crypt(const u32 *rk, u32 *out, const u32 *in) +{ + u32 x[4], i, t; + + for (i = 0; i < 4; ++i) + x[i] = get_unaligned_be32(&in[i]); + + for (i = 0; i < 32; ++i) { + t = sm4_round(x, rk[i]); + x[0] = x[1]; + x[1] = x[2]; + x[2] = x[3]; + x[3] = t; + } + + for (i = 0; i < 4; ++i) + put_unaligned_be32(x[3 - i], &out[i]); +} + +/* encrypt a block of text */ + +void crypto_sm4_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + const struct crypto_sm4_ctx *ctx = crypto_tfm_ctx(tfm); + + sm4_do_crypt(ctx->rkey_enc, (u32 *)out, (u32 *)in); +} +EXPORT_SYMBOL_GPL(crypto_sm4_encrypt); + +/* decrypt a block of text */ + +void crypto_sm4_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) +{ + const struct crypto_sm4_ctx *ctx = crypto_tfm_ctx(tfm); + + sm4_do_crypt(ctx->rkey_dec, (u32 *)out, (u32 *)in); +} +EXPORT_SYMBOL_GPL(crypto_sm4_decrypt); + +static struct crypto_alg sm4_alg = { + .cra_name = "sm4", + .cra_driver_name = "sm4-generic", + .cra_priority = 100, + .cra_flags = CRYPTO_ALG_TYPE_CIPHER, + .cra_blocksize = SM4_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct crypto_sm4_ctx), + .cra_module = THIS_MODULE, + .cra_u = { + .cipher = { + .cia_min_keysize = SM4_KEY_SIZE, + .cia_max_keysize = SM4_KEY_SIZE, + .cia_setkey = crypto_sm4_set_key, + .cia_encrypt = crypto_sm4_encrypt, + .cia_decrypt = crypto_sm4_decrypt + } + } +}; + +static int __init sm4_init(void) +{ + return crypto_register_alg(&sm4_alg); +} + +static void __exit sm4_fini(void) +{ + crypto_unregister_alg(&sm4_alg); +} + +module_init(sm4_init); +module_exit(sm4_fini); + +MODULE_DESCRIPTION("SM4 Cipher Algorithm"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_CRYPTO("sm4"); +MODULE_ALIAS_CRYPTO("sm4-generic"); |