1/*
  2 * SM3 secure hash, as specified by OSCCA GM/T 0004-2012 SM3 and
  3 * described at https://tools.ietf.org/html/draft-shen-sm3-hash-01
  4 *
  5 * Copyright (C) 2017 ARM Limited or its affiliates.
  6 * Written by Gilad Ben-Yossef <gilad@benyossef.com>
  7 *
  8 * This program is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License version 2 as
 10 * published by the Free Software Foundation.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 19 */
 20
 21#include <crypto/internal/hash.h>
 22#include <linux/init.h>
 23#include <linux/module.h>
 24#include <linux/mm.h>
 25#include <linux/types.h>
 26#include <crypto/sm3.h>
 27#include <crypto/sm3_base.h>
 28#include <linux/bitops.h>
 29#include <asm/byteorder.h>
 30#include <asm/unaligned.h>
 31
 32const u8 sm3_zero_message_hash[SM3_DIGEST_SIZE] = {
 33	0x1A, 0xB2, 0x1D, 0x83, 0x55, 0xCF, 0xA1, 0x7F,
 34	0x8e, 0x61, 0x19, 0x48, 0x31, 0xE8, 0x1A, 0x8F,
 35	0x22, 0xBE, 0xC8, 0xC7, 0x28, 0xFE, 0xFB, 0x74,
 36	0x7E, 0xD0, 0x35, 0xEB, 0x50, 0x82, 0xAA, 0x2B
 37};
 38EXPORT_SYMBOL_GPL(sm3_zero_message_hash);
 39
 40static inline u32 p0(u32 x)
 41{
 42	return x ^ rol32(x, 9) ^ rol32(x, 17);
 43}
 44
 45static inline u32 p1(u32 x)
 46{
 47	return x ^ rol32(x, 15) ^ rol32(x, 23);
 48}
 49
 50static inline u32 ff(unsigned int n, u32 a, u32 b, u32 c)
 51{
 52	return (n < 16) ? (a ^ b ^ c) : ((a & b) | (a & c) | (b & c));
 53}
 54
 55static inline u32 gg(unsigned int n, u32 e, u32 f, u32 g)
 56{
 57	return (n < 16) ? (e ^ f ^ g) : ((e & f) | ((~e) & g));
 58}
 59
 60static inline u32 t(unsigned int n)
 61{
 62	return (n < 16) ? SM3_T1 : SM3_T2;
 63}
 64
 65static void sm3_expand(u32 *t, u32 *w, u32 *wt)
 66{
 67	int i;
 68	unsigned int tmp;
 69
 70	/* load the input */
 71	for (i = 0; i <= 15; i++)
 72		w[i] = get_unaligned_be32((__u32 *)t + i);
 73
 74	for (i = 16; i <= 67; i++) {
 75		tmp = w[i - 16] ^ w[i - 9] ^ rol32(w[i - 3], 15);
 76		w[i] = p1(tmp) ^ (rol32(w[i - 13], 7)) ^ w[i - 6];
 77	}
 78
 79	for (i = 0; i <= 63; i++)
 80		wt[i] = w[i] ^ w[i + 4];
 81}
 82
 83static void sm3_compress(u32 *w, u32 *wt, u32 *m)
 84{
 85	u32 ss1;
 86	u32 ss2;
 87	u32 tt1;
 88	u32 tt2;
 89	u32 a, b, c, d, e, f, g, h;
 90	int i;
 91
 92	a = m[0];
 93	b = m[1];
 94	c = m[2];
 95	d = m[3];
 96	e = m[4];
 97	f = m[5];
 98	g = m[6];
 99	h = m[7];
100
101	for (i = 0; i <= 63; i++) {
102
103		ss1 = rol32((rol32(a, 12) + e + rol32(t(i), i)), 7);
104
105		ss2 = ss1 ^ rol32(a, 12);
106
107		tt1 = ff(i, a, b, c) + d + ss2 + *wt;
108		wt++;
109
110		tt2 = gg(i, e, f, g) + h + ss1 + *w;
111		w++;
112
113		d = c;
114		c = rol32(b, 9);
115		b = a;
116		a = tt1;
117		h = g;
118		g = rol32(f, 19);
119		f = e;
120		e = p0(tt2);
121	}
122
123	m[0] = a ^ m[0];
124	m[1] = b ^ m[1];
125	m[2] = c ^ m[2];
126	m[3] = d ^ m[3];
127	m[4] = e ^ m[4];
128	m[5] = f ^ m[5];
129	m[6] = g ^ m[6];
130	m[7] = h ^ m[7];
131
132	a = b = c = d = e = f = g = h = ss1 = ss2 = tt1 = tt2 = 0;
133}
134
135static void sm3_transform(struct sm3_state *sst, u8 const *src)
136{
137	unsigned int w[68];
138	unsigned int wt[64];
139
140	sm3_expand((u32 *)src, w, wt);
141	sm3_compress(w, wt, sst->state);
142
143	memzero_explicit(w, sizeof(w));
144	memzero_explicit(wt, sizeof(wt));
145}
146
147static void sm3_generic_block_fn(struct sm3_state *sst, u8 const *src,
148				    int blocks)
149{
150	while (blocks--) {
151		sm3_transform(sst, src);
152		src += SM3_BLOCK_SIZE;
153	}
154}
155
156int crypto_sm3_update(struct shash_desc *desc, const u8 *data,
157			  unsigned int len)
158{
159	return sm3_base_do_update(desc, data, len, sm3_generic_block_fn);
160}
161EXPORT_SYMBOL(crypto_sm3_update);
162
163static int sm3_final(struct shash_desc *desc, u8 *out)
164{
165	sm3_base_do_finalize(desc, sm3_generic_block_fn);
166	return sm3_base_finish(desc, out);
167}
168
169int crypto_sm3_finup(struct shash_desc *desc, const u8 *data,
170			unsigned int len, u8 *hash)
171{
172	sm3_base_do_update(desc, data, len, sm3_generic_block_fn);
173	return sm3_final(desc, hash);
174}
175EXPORT_SYMBOL(crypto_sm3_finup);
176
177static struct shash_alg sm3_alg = {
178	.digestsize	=	SM3_DIGEST_SIZE,
179	.init		=	sm3_base_init,
180	.update		=	crypto_sm3_update,
181	.final		=	sm3_final,
182	.finup		=	crypto_sm3_finup,
183	.descsize	=	sizeof(struct sm3_state),
184	.base		=	{
185		.cra_name	 =	"sm3",
186		.cra_driver_name =	"sm3-generic",
187		.cra_flags	 =	CRYPTO_ALG_TYPE_SHASH,
188		.cra_blocksize	 =	SM3_BLOCK_SIZE,
189		.cra_module	 =	THIS_MODULE,
190	}
191};
192
193static int __init sm3_generic_mod_init(void)
194{
195	return crypto_register_shash(&sm3_alg);
196}
197
198static void __exit sm3_generic_mod_fini(void)
199{
200	crypto_unregister_shash(&sm3_alg);
201}
202
203module_init(sm3_generic_mod_init);
204module_exit(sm3_generic_mod_fini);
205
206MODULE_LICENSE("GPL v2");
207MODULE_DESCRIPTION("SM3 Secure Hash Algorithm");
208
209MODULE_ALIAS_CRYPTO("sm3");
210MODULE_ALIAS_CRYPTO("sm3-generic");