xref: /linux-6.15/lib/crypto/sha256.c (revision b8399819)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * SHA-256, as specified in
4  * http://csrc.nist.gov/groups/STM/cavp/documents/shs/sha256-384-512.pdf
5  *
6  * SHA-256 code by Jean-Luc Cooke <[email protected]>.
7  *
8  * Copyright (c) Jean-Luc Cooke <[email protected]>
9  * Copyright (c) Andrew McDonald <[email protected]>
10  * Copyright (c) 2002 James Morris <[email protected]>
11  * Copyright (c) 2014 Red Hat Inc.
12  */
13 
14 #include <linux/bitops.h>
15 #include <linux/export.h>
16 #include <linux/module.h>
17 #include <linux/string.h>
18 #include <crypto/sha.h>
19 #include <asm/unaligned.h>
20 
21 static inline u32 Ch(u32 x, u32 y, u32 z)
22 {
23 	return z ^ (x & (y ^ z));
24 }
25 
26 static inline u32 Maj(u32 x, u32 y, u32 z)
27 {
28 	return (x & y) | (z & (x | y));
29 }
30 
31 #define e0(x)       (ror32(x, 2) ^ ror32(x, 13) ^ ror32(x, 22))
32 #define e1(x)       (ror32(x, 6) ^ ror32(x, 11) ^ ror32(x, 25))
33 #define s0(x)       (ror32(x, 7) ^ ror32(x, 18) ^ (x >> 3))
34 #define s1(x)       (ror32(x, 17) ^ ror32(x, 19) ^ (x >> 10))
35 
36 static inline void LOAD_OP(int I, u32 *W, const u8 *input)
37 {
38 	W[I] = get_unaligned_be32((__u32 *)input + I);
39 }
40 
41 static inline void BLEND_OP(int I, u32 *W)
42 {
43 	W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16];
44 }
45 
46 static void sha256_transform(u32 *state, const u8 *input, u32 *W)
47 {
48 	u32 a, b, c, d, e, f, g, h, t1, t2;
49 	int i;
50 
51 	/* load the input */
52 	for (i = 0; i < 16; i++)
53 		LOAD_OP(i, W, input);
54 
55 	/* now blend */
56 	for (i = 16; i < 64; i++)
57 		BLEND_OP(i, W);
58 
59 	/* load the state into our registers */
60 	a = state[0];  b = state[1];  c = state[2];  d = state[3];
61 	e = state[4];  f = state[5];  g = state[6];  h = state[7];
62 
63 	/* now iterate */
64 	t1 = h + e1(e) + Ch(e, f, g) + 0x428a2f98 + W[0];
65 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
66 	t1 = g + e1(d) + Ch(d, e, f) + 0x71374491 + W[1];
67 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
68 	t1 = f + e1(c) + Ch(c, d, e) + 0xb5c0fbcf + W[2];
69 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
70 	t1 = e + e1(b) + Ch(b, c, d) + 0xe9b5dba5 + W[3];
71 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
72 	t1 = d + e1(a) + Ch(a, b, c) + 0x3956c25b + W[4];
73 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
74 	t1 = c + e1(h) + Ch(h, a, b) + 0x59f111f1 + W[5];
75 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
76 	t1 = b + e1(g) + Ch(g, h, a) + 0x923f82a4 + W[6];
77 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
78 	t1 = a + e1(f) + Ch(f, g, h) + 0xab1c5ed5 + W[7];
79 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
80 
81 	t1 = h + e1(e) + Ch(e, f, g) + 0xd807aa98 + W[8];
82 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
83 	t1 = g + e1(d) + Ch(d, e, f) + 0x12835b01 + W[9];
84 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
85 	t1 = f + e1(c) + Ch(c, d, e) + 0x243185be + W[10];
86 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
87 	t1 = e + e1(b) + Ch(b, c, d) + 0x550c7dc3 + W[11];
88 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
89 	t1 = d + e1(a) + Ch(a, b, c) + 0x72be5d74 + W[12];
90 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
91 	t1 = c + e1(h) + Ch(h, a, b) + 0x80deb1fe + W[13];
92 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
93 	t1 = b + e1(g) + Ch(g, h, a) + 0x9bdc06a7 + W[14];
94 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
95 	t1 = a + e1(f) + Ch(f, g, h) + 0xc19bf174 + W[15];
96 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
97 
98 	t1 = h + e1(e) + Ch(e, f, g) + 0xe49b69c1 + W[16];
99 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
100 	t1 = g + e1(d) + Ch(d, e, f) + 0xefbe4786 + W[17];
101 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
102 	t1 = f + e1(c) + Ch(c, d, e) + 0x0fc19dc6 + W[18];
103 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
104 	t1 = e + e1(b) + Ch(b, c, d) + 0x240ca1cc + W[19];
105 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
106 	t1 = d + e1(a) + Ch(a, b, c) + 0x2de92c6f + W[20];
107 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
108 	t1 = c + e1(h) + Ch(h, a, b) + 0x4a7484aa + W[21];
109 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
110 	t1 = b + e1(g) + Ch(g, h, a) + 0x5cb0a9dc + W[22];
111 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
112 	t1 = a + e1(f) + Ch(f, g, h) + 0x76f988da + W[23];
113 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
114 
115 	t1 = h + e1(e) + Ch(e, f, g) + 0x983e5152 + W[24];
116 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
117 	t1 = g + e1(d) + Ch(d, e, f) + 0xa831c66d + W[25];
118 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
119 	t1 = f + e1(c) + Ch(c, d, e) + 0xb00327c8 + W[26];
120 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
121 	t1 = e + e1(b) + Ch(b, c, d) + 0xbf597fc7 + W[27];
122 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
123 	t1 = d + e1(a) + Ch(a, b, c) + 0xc6e00bf3 + W[28];
124 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
125 	t1 = c + e1(h) + Ch(h, a, b) + 0xd5a79147 + W[29];
126 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
127 	t1 = b + e1(g) + Ch(g, h, a) + 0x06ca6351 + W[30];
128 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
129 	t1 = a + e1(f) + Ch(f, g, h) + 0x14292967 + W[31];
130 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
131 
132 	t1 = h + e1(e) + Ch(e, f, g) + 0x27b70a85 + W[32];
133 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
134 	t1 = g + e1(d) + Ch(d, e, f) + 0x2e1b2138 + W[33];
135 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
136 	t1 = f + e1(c) + Ch(c, d, e) + 0x4d2c6dfc + W[34];
137 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
138 	t1 = e + e1(b) + Ch(b, c, d) + 0x53380d13 + W[35];
139 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
140 	t1 = d + e1(a) + Ch(a, b, c) + 0x650a7354 + W[36];
141 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
142 	t1 = c + e1(h) + Ch(h, a, b) + 0x766a0abb + W[37];
143 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
144 	t1 = b + e1(g) + Ch(g, h, a) + 0x81c2c92e + W[38];
145 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
146 	t1 = a + e1(f) + Ch(f, g, h) + 0x92722c85 + W[39];
147 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
148 
149 	t1 = h + e1(e) + Ch(e, f, g) + 0xa2bfe8a1 + W[40];
150 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
151 	t1 = g + e1(d) + Ch(d, e, f) + 0xa81a664b + W[41];
152 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
153 	t1 = f + e1(c) + Ch(c, d, e) + 0xc24b8b70 + W[42];
154 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
155 	t1 = e + e1(b) + Ch(b, c, d) + 0xc76c51a3 + W[43];
156 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
157 	t1 = d + e1(a) + Ch(a, b, c) + 0xd192e819 + W[44];
158 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
159 	t1 = c + e1(h) + Ch(h, a, b) + 0xd6990624 + W[45];
160 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
161 	t1 = b + e1(g) + Ch(g, h, a) + 0xf40e3585 + W[46];
162 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
163 	t1 = a + e1(f) + Ch(f, g, h) + 0x106aa070 + W[47];
164 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
165 
166 	t1 = h + e1(e) + Ch(e, f, g) + 0x19a4c116 + W[48];
167 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
168 	t1 = g + e1(d) + Ch(d, e, f) + 0x1e376c08 + W[49];
169 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
170 	t1 = f + e1(c) + Ch(c, d, e) + 0x2748774c + W[50];
171 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
172 	t1 = e + e1(b) + Ch(b, c, d) + 0x34b0bcb5 + W[51];
173 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
174 	t1 = d + e1(a) + Ch(a, b, c) + 0x391c0cb3 + W[52];
175 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
176 	t1 = c + e1(h) + Ch(h, a, b) + 0x4ed8aa4a + W[53];
177 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
178 	t1 = b + e1(g) + Ch(g, h, a) + 0x5b9cca4f + W[54];
179 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
180 	t1 = a + e1(f) + Ch(f, g, h) + 0x682e6ff3 + W[55];
181 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
182 
183 	t1 = h + e1(e) + Ch(e, f, g) + 0x748f82ee + W[56];
184 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
185 	t1 = g + e1(d) + Ch(d, e, f) + 0x78a5636f + W[57];
186 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
187 	t1 = f + e1(c) + Ch(c, d, e) + 0x84c87814 + W[58];
188 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
189 	t1 = e + e1(b) + Ch(b, c, d) + 0x8cc70208 + W[59];
190 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
191 	t1 = d + e1(a) + Ch(a, b, c) + 0x90befffa + W[60];
192 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
193 	t1 = c + e1(h) + Ch(h, a, b) + 0xa4506ceb + W[61];
194 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
195 	t1 = b + e1(g) + Ch(g, h, a) + 0xbef9a3f7 + W[62];
196 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
197 	t1 = a + e1(f) + Ch(f, g, h) + 0xc67178f2 + W[63];
198 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;
199 
200 	state[0] += a; state[1] += b; state[2] += c; state[3] += d;
201 	state[4] += e; state[5] += f; state[6] += g; state[7] += h;
202 }
203 
204 void sha256_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
205 {
206 	unsigned int partial, done;
207 	const u8 *src;
208 	u32 W[64];
209 
210 	partial = sctx->count & 0x3f;
211 	sctx->count += len;
212 	done = 0;
213 	src = data;
214 
215 	if ((partial + len) > 63) {
216 		if (partial) {
217 			done = -partial;
218 			memcpy(sctx->buf + partial, data, done + 64);
219 			src = sctx->buf;
220 		}
221 
222 		do {
223 			sha256_transform(sctx->state, src, W);
224 			done += 64;
225 			src = data + done;
226 		} while (done + 63 < len);
227 
228 		memzero_explicit(W, sizeof(W));
229 
230 		partial = 0;
231 	}
232 	memcpy(sctx->buf + partial, src, len - done);
233 }
234 EXPORT_SYMBOL(sha256_update);
235 
236 void sha224_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
237 {
238 	sha256_update(sctx, data, len);
239 }
240 EXPORT_SYMBOL(sha224_update);
241 
242 static void __sha256_final(struct sha256_state *sctx, u8 *out, int digest_words)
243 {
244 	__be32 *dst = (__be32 *)out;
245 	__be64 bits;
246 	unsigned int index, pad_len;
247 	int i;
248 	static const u8 padding[64] = { 0x80, };
249 
250 	/* Save number of bits */
251 	bits = cpu_to_be64(sctx->count << 3);
252 
253 	/* Pad out to 56 mod 64. */
254 	index = sctx->count & 0x3f;
255 	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
256 	sha256_update(sctx, padding, pad_len);
257 
258 	/* Append length (before padding) */
259 	sha256_update(sctx, (const u8 *)&bits, sizeof(bits));
260 
261 	/* Store state in digest */
262 	for (i = 0; i < digest_words; i++)
263 		put_unaligned_be32(sctx->state[i], &dst[i]);
264 
265 	/* Zeroize sensitive information. */
266 	memzero_explicit(sctx, sizeof(*sctx));
267 }
268 
269 void sha256_final(struct sha256_state *sctx, u8 *out)
270 {
271 	__sha256_final(sctx, out, 8);
272 }
273 EXPORT_SYMBOL(sha256_final);
274 
275 void sha224_final(struct sha256_state *sctx, u8 *out)
276 {
277 	__sha256_final(sctx, out, 7);
278 }
279 EXPORT_SYMBOL(sha224_final);
280 
281 void sha256(const u8 *data, unsigned int len, u8 *out)
282 {
283 	struct sha256_state sctx;
284 
285 	sha256_init(&sctx);
286 	sha256_update(&sctx, data, len);
287 	sha256_final(&sctx, out);
288 }
289 EXPORT_SYMBOL(sha256);
290 
291 MODULE_LICENSE("GPL");
292