xref: /openbmc/u-boot/lib/sha256.c (revision 9fc2ed40)
1 /*
2  * FIPS-180-2 compliant SHA-256 implementation
3  *
4  * Copyright (C) 2001-2003  Christophe Devine
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 #ifndef USE_HOSTCC
10 #include <common.h>
11 #endif /* USE_HOSTCC */
12 #include <watchdog.h>
13 #include <linux/string.h>
14 #include <sha256.h>
15 
16 /*
17  * 32-bit integer manipulation macros (big endian)
18  */
19 #ifndef GET_UINT32_BE
20 #define GET_UINT32_BE(n,b,i) {				\
21 	(n) = ( (unsigned long) (b)[(i)    ] << 24 )	\
22 	    | ( (unsigned long) (b)[(i) + 1] << 16 )	\
23 	    | ( (unsigned long) (b)[(i) + 2] <<  8 )	\
24 	    | ( (unsigned long) (b)[(i) + 3]       );	\
25 }
26 #endif
27 #ifndef PUT_UINT32_BE
28 #define PUT_UINT32_BE(n,b,i) {				\
29 	(b)[(i)    ] = (unsigned char) ( (n) >> 24 );	\
30 	(b)[(i) + 1] = (unsigned char) ( (n) >> 16 );	\
31 	(b)[(i) + 2] = (unsigned char) ( (n) >>  8 );	\
32 	(b)[(i) + 3] = (unsigned char) ( (n)       );	\
33 }
34 #endif
35 
36 void sha256_starts(sha256_context * ctx)
37 {
38 	ctx->total[0] = 0;
39 	ctx->total[1] = 0;
40 
41 	ctx->state[0] = 0x6A09E667;
42 	ctx->state[1] = 0xBB67AE85;
43 	ctx->state[2] = 0x3C6EF372;
44 	ctx->state[3] = 0xA54FF53A;
45 	ctx->state[4] = 0x510E527F;
46 	ctx->state[5] = 0x9B05688C;
47 	ctx->state[6] = 0x1F83D9AB;
48 	ctx->state[7] = 0x5BE0CD19;
49 }
50 
51 static void sha256_process(sha256_context *ctx, const uint8_t data[64])
52 {
53 	uint32_t temp1, temp2;
54 	uint32_t W[64];
55 	uint32_t A, B, C, D, E, F, G, H;
56 
57 	GET_UINT32_BE(W[0], data, 0);
58 	GET_UINT32_BE(W[1], data, 4);
59 	GET_UINT32_BE(W[2], data, 8);
60 	GET_UINT32_BE(W[3], data, 12);
61 	GET_UINT32_BE(W[4], data, 16);
62 	GET_UINT32_BE(W[5], data, 20);
63 	GET_UINT32_BE(W[6], data, 24);
64 	GET_UINT32_BE(W[7], data, 28);
65 	GET_UINT32_BE(W[8], data, 32);
66 	GET_UINT32_BE(W[9], data, 36);
67 	GET_UINT32_BE(W[10], data, 40);
68 	GET_UINT32_BE(W[11], data, 44);
69 	GET_UINT32_BE(W[12], data, 48);
70 	GET_UINT32_BE(W[13], data, 52);
71 	GET_UINT32_BE(W[14], data, 56);
72 	GET_UINT32_BE(W[15], data, 60);
73 
74 #define SHR(x,n) ((x & 0xFFFFFFFF) >> n)
75 #define ROTR(x,n) (SHR(x,n) | (x << (32 - n)))
76 
77 #define S0(x) (ROTR(x, 7) ^ ROTR(x,18) ^ SHR(x, 3))
78 #define S1(x) (ROTR(x,17) ^ ROTR(x,19) ^ SHR(x,10))
79 
80 #define S2(x) (ROTR(x, 2) ^ ROTR(x,13) ^ ROTR(x,22))
81 #define S3(x) (ROTR(x, 6) ^ ROTR(x,11) ^ ROTR(x,25))
82 
83 #define F0(x,y,z) ((x & y) | (z & (x | y)))
84 #define F1(x,y,z) (z ^ (x & (y ^ z)))
85 
86 #define R(t)					\
87 (						\
88 	W[t] = S1(W[t - 2]) + W[t - 7] +	\
89 		S0(W[t - 15]) + W[t - 16]	\
90 )
91 
92 #define P(a,b,c,d,e,f,g,h,x,K) {		\
93 	temp1 = h + S3(e) + F1(e,f,g) + K + x;	\
94 	temp2 = S2(a) + F0(a,b,c);		\
95 	d += temp1; h = temp1 + temp2;		\
96 }
97 
98 	A = ctx->state[0];
99 	B = ctx->state[1];
100 	C = ctx->state[2];
101 	D = ctx->state[3];
102 	E = ctx->state[4];
103 	F = ctx->state[5];
104 	G = ctx->state[6];
105 	H = ctx->state[7];
106 
107 	P(A, B, C, D, E, F, G, H, W[0], 0x428A2F98);
108 	P(H, A, B, C, D, E, F, G, W[1], 0x71374491);
109 	P(G, H, A, B, C, D, E, F, W[2], 0xB5C0FBCF);
110 	P(F, G, H, A, B, C, D, E, W[3], 0xE9B5DBA5);
111 	P(E, F, G, H, A, B, C, D, W[4], 0x3956C25B);
112 	P(D, E, F, G, H, A, B, C, W[5], 0x59F111F1);
113 	P(C, D, E, F, G, H, A, B, W[6], 0x923F82A4);
114 	P(B, C, D, E, F, G, H, A, W[7], 0xAB1C5ED5);
115 	P(A, B, C, D, E, F, G, H, W[8], 0xD807AA98);
116 	P(H, A, B, C, D, E, F, G, W[9], 0x12835B01);
117 	P(G, H, A, B, C, D, E, F, W[10], 0x243185BE);
118 	P(F, G, H, A, B, C, D, E, W[11], 0x550C7DC3);
119 	P(E, F, G, H, A, B, C, D, W[12], 0x72BE5D74);
120 	P(D, E, F, G, H, A, B, C, W[13], 0x80DEB1FE);
121 	P(C, D, E, F, G, H, A, B, W[14], 0x9BDC06A7);
122 	P(B, C, D, E, F, G, H, A, W[15], 0xC19BF174);
123 	P(A, B, C, D, E, F, G, H, R(16), 0xE49B69C1);
124 	P(H, A, B, C, D, E, F, G, R(17), 0xEFBE4786);
125 	P(G, H, A, B, C, D, E, F, R(18), 0x0FC19DC6);
126 	P(F, G, H, A, B, C, D, E, R(19), 0x240CA1CC);
127 	P(E, F, G, H, A, B, C, D, R(20), 0x2DE92C6F);
128 	P(D, E, F, G, H, A, B, C, R(21), 0x4A7484AA);
129 	P(C, D, E, F, G, H, A, B, R(22), 0x5CB0A9DC);
130 	P(B, C, D, E, F, G, H, A, R(23), 0x76F988DA);
131 	P(A, B, C, D, E, F, G, H, R(24), 0x983E5152);
132 	P(H, A, B, C, D, E, F, G, R(25), 0xA831C66D);
133 	P(G, H, A, B, C, D, E, F, R(26), 0xB00327C8);
134 	P(F, G, H, A, B, C, D, E, R(27), 0xBF597FC7);
135 	P(E, F, G, H, A, B, C, D, R(28), 0xC6E00BF3);
136 	P(D, E, F, G, H, A, B, C, R(29), 0xD5A79147);
137 	P(C, D, E, F, G, H, A, B, R(30), 0x06CA6351);
138 	P(B, C, D, E, F, G, H, A, R(31), 0x14292967);
139 	P(A, B, C, D, E, F, G, H, R(32), 0x27B70A85);
140 	P(H, A, B, C, D, E, F, G, R(33), 0x2E1B2138);
141 	P(G, H, A, B, C, D, E, F, R(34), 0x4D2C6DFC);
142 	P(F, G, H, A, B, C, D, E, R(35), 0x53380D13);
143 	P(E, F, G, H, A, B, C, D, R(36), 0x650A7354);
144 	P(D, E, F, G, H, A, B, C, R(37), 0x766A0ABB);
145 	P(C, D, E, F, G, H, A, B, R(38), 0x81C2C92E);
146 	P(B, C, D, E, F, G, H, A, R(39), 0x92722C85);
147 	P(A, B, C, D, E, F, G, H, R(40), 0xA2BFE8A1);
148 	P(H, A, B, C, D, E, F, G, R(41), 0xA81A664B);
149 	P(G, H, A, B, C, D, E, F, R(42), 0xC24B8B70);
150 	P(F, G, H, A, B, C, D, E, R(43), 0xC76C51A3);
151 	P(E, F, G, H, A, B, C, D, R(44), 0xD192E819);
152 	P(D, E, F, G, H, A, B, C, R(45), 0xD6990624);
153 	P(C, D, E, F, G, H, A, B, R(46), 0xF40E3585);
154 	P(B, C, D, E, F, G, H, A, R(47), 0x106AA070);
155 	P(A, B, C, D, E, F, G, H, R(48), 0x19A4C116);
156 	P(H, A, B, C, D, E, F, G, R(49), 0x1E376C08);
157 	P(G, H, A, B, C, D, E, F, R(50), 0x2748774C);
158 	P(F, G, H, A, B, C, D, E, R(51), 0x34B0BCB5);
159 	P(E, F, G, H, A, B, C, D, R(52), 0x391C0CB3);
160 	P(D, E, F, G, H, A, B, C, R(53), 0x4ED8AA4A);
161 	P(C, D, E, F, G, H, A, B, R(54), 0x5B9CCA4F);
162 	P(B, C, D, E, F, G, H, A, R(55), 0x682E6FF3);
163 	P(A, B, C, D, E, F, G, H, R(56), 0x748F82EE);
164 	P(H, A, B, C, D, E, F, G, R(57), 0x78A5636F);
165 	P(G, H, A, B, C, D, E, F, R(58), 0x84C87814);
166 	P(F, G, H, A, B, C, D, E, R(59), 0x8CC70208);
167 	P(E, F, G, H, A, B, C, D, R(60), 0x90BEFFFA);
168 	P(D, E, F, G, H, A, B, C, R(61), 0xA4506CEB);
169 	P(C, D, E, F, G, H, A, B, R(62), 0xBEF9A3F7);
170 	P(B, C, D, E, F, G, H, A, R(63), 0xC67178F2);
171 
172 	ctx->state[0] += A;
173 	ctx->state[1] += B;
174 	ctx->state[2] += C;
175 	ctx->state[3] += D;
176 	ctx->state[4] += E;
177 	ctx->state[5] += F;
178 	ctx->state[6] += G;
179 	ctx->state[7] += H;
180 }
181 
182 void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length)
183 {
184 	uint32_t left, fill;
185 
186 	if (!length)
187 		return;
188 
189 	left = ctx->total[0] & 0x3F;
190 	fill = 64 - left;
191 
192 	ctx->total[0] += length;
193 	ctx->total[0] &= 0xFFFFFFFF;
194 
195 	if (ctx->total[0] < length)
196 		ctx->total[1]++;
197 
198 	if (left && length >= fill) {
199 		memcpy((void *) (ctx->buffer + left), (void *) input, fill);
200 		sha256_process(ctx, ctx->buffer);
201 		length -= fill;
202 		input += fill;
203 		left = 0;
204 	}
205 
206 	while (length >= 64) {
207 		sha256_process(ctx, input);
208 		length -= 64;
209 		input += 64;
210 	}
211 
212 	if (length)
213 		memcpy((void *) (ctx->buffer + left), (void *) input, length);
214 }
215 
216 static uint8_t sha256_padding[64] = {
217 	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
218 	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
219 	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
220 	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
221 };
222 
223 void sha256_finish(sha256_context * ctx, uint8_t digest[32])
224 {
225 	uint32_t last, padn;
226 	uint32_t high, low;
227 	uint8_t msglen[8];
228 
229 	high = ((ctx->total[0] >> 29)
230 		| (ctx->total[1] << 3));
231 	low = (ctx->total[0] << 3);
232 
233 	PUT_UINT32_BE(high, msglen, 0);
234 	PUT_UINT32_BE(low, msglen, 4);
235 
236 	last = ctx->total[0] & 0x3F;
237 	padn = (last < 56) ? (56 - last) : (120 - last);
238 
239 	sha256_update(ctx, sha256_padding, padn);
240 	sha256_update(ctx, msglen, 8);
241 
242 	PUT_UINT32_BE(ctx->state[0], digest, 0);
243 	PUT_UINT32_BE(ctx->state[1], digest, 4);
244 	PUT_UINT32_BE(ctx->state[2], digest, 8);
245 	PUT_UINT32_BE(ctx->state[3], digest, 12);
246 	PUT_UINT32_BE(ctx->state[4], digest, 16);
247 	PUT_UINT32_BE(ctx->state[5], digest, 20);
248 	PUT_UINT32_BE(ctx->state[6], digest, 24);
249 	PUT_UINT32_BE(ctx->state[7], digest, 28);
250 }
251 
252 /*
253  * Output = SHA-256( input buffer ). Trigger the watchdog every 'chunk_sz'
254  * bytes of input processed.
255  */
256 void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
257 		unsigned char *output, unsigned int chunk_sz)
258 {
259 	sha256_context ctx;
260 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
261 	const unsigned char *end;
262 	unsigned char *curr;
263 	int chunk;
264 #endif
265 
266 	sha256_starts(&ctx);
267 
268 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
269 	curr = (unsigned char *)input;
270 	end = input + ilen;
271 	while (curr < end) {
272 		chunk = end - curr;
273 		if (chunk > chunk_sz)
274 			chunk = chunk_sz;
275 		sha256_update(&ctx, curr, chunk);
276 		curr += chunk;
277 		WATCHDOG_RESET();
278 	}
279 #else
280 	sha256_update(&ctx, input, ilen);
281 #endif
282 
283 	sha256_finish(&ctx, output);
284 }
285