xref: /openbmc/u-boot/lib/sha256.c (revision 225f5eec)
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 #include <linux/string.h>
12 #else
13 #include <string.h>
14 #endif /* USE_HOSTCC */
15 #include <watchdog.h>
16 #include <u-boot/sha256.h>
17 
18 /*
19  * 32-bit integer manipulation macros (big endian)
20  */
21 #ifndef GET_UINT32_BE
22 #define GET_UINT32_BE(n,b,i) {				\
23 	(n) = ( (unsigned long) (b)[(i)    ] << 24 )	\
24 	    | ( (unsigned long) (b)[(i) + 1] << 16 )	\
25 	    | ( (unsigned long) (b)[(i) + 2] <<  8 )	\
26 	    | ( (unsigned long) (b)[(i) + 3]       );	\
27 }
28 #endif
29 #ifndef PUT_UINT32_BE
30 #define PUT_UINT32_BE(n,b,i) {				\
31 	(b)[(i)    ] = (unsigned char) ( (n) >> 24 );	\
32 	(b)[(i) + 1] = (unsigned char) ( (n) >> 16 );	\
33 	(b)[(i) + 2] = (unsigned char) ( (n) >>  8 );	\
34 	(b)[(i) + 3] = (unsigned char) ( (n)       );	\
35 }
36 #endif
37 
38 void sha256_starts(sha256_context * ctx)
39 {
40 	ctx->total[0] = 0;
41 	ctx->total[1] = 0;
42 
43 	ctx->state[0] = 0x6A09E667;
44 	ctx->state[1] = 0xBB67AE85;
45 	ctx->state[2] = 0x3C6EF372;
46 	ctx->state[3] = 0xA54FF53A;
47 	ctx->state[4] = 0x510E527F;
48 	ctx->state[5] = 0x9B05688C;
49 	ctx->state[6] = 0x1F83D9AB;
50 	ctx->state[7] = 0x5BE0CD19;
51 }
52 
53 static void sha256_process(sha256_context *ctx, const uint8_t data[64])
54 {
55 	uint32_t temp1, temp2;
56 	uint32_t W[64];
57 	uint32_t A, B, C, D, E, F, G, H;
58 
59 	GET_UINT32_BE(W[0], data, 0);
60 	GET_UINT32_BE(W[1], data, 4);
61 	GET_UINT32_BE(W[2], data, 8);
62 	GET_UINT32_BE(W[3], data, 12);
63 	GET_UINT32_BE(W[4], data, 16);
64 	GET_UINT32_BE(W[5], data, 20);
65 	GET_UINT32_BE(W[6], data, 24);
66 	GET_UINT32_BE(W[7], data, 28);
67 	GET_UINT32_BE(W[8], data, 32);
68 	GET_UINT32_BE(W[9], data, 36);
69 	GET_UINT32_BE(W[10], data, 40);
70 	GET_UINT32_BE(W[11], data, 44);
71 	GET_UINT32_BE(W[12], data, 48);
72 	GET_UINT32_BE(W[13], data, 52);
73 	GET_UINT32_BE(W[14], data, 56);
74 	GET_UINT32_BE(W[15], data, 60);
75 
76 #define SHR(x,n) ((x & 0xFFFFFFFF) >> n)
77 #define ROTR(x,n) (SHR(x,n) | (x << (32 - n)))
78 
79 #define S0(x) (ROTR(x, 7) ^ ROTR(x,18) ^ SHR(x, 3))
80 #define S1(x) (ROTR(x,17) ^ ROTR(x,19) ^ SHR(x,10))
81 
82 #define S2(x) (ROTR(x, 2) ^ ROTR(x,13) ^ ROTR(x,22))
83 #define S3(x) (ROTR(x, 6) ^ ROTR(x,11) ^ ROTR(x,25))
84 
85 #define F0(x,y,z) ((x & y) | (z & (x | y)))
86 #define F1(x,y,z) (z ^ (x & (y ^ z)))
87 
88 #define R(t)					\
89 (						\
90 	W[t] = S1(W[t - 2]) + W[t - 7] +	\
91 		S0(W[t - 15]) + W[t - 16]	\
92 )
93 
94 #define P(a,b,c,d,e,f,g,h,x,K) {		\
95 	temp1 = h + S3(e) + F1(e,f,g) + K + x;	\
96 	temp2 = S2(a) + F0(a,b,c);		\
97 	d += temp1; h = temp1 + temp2;		\
98 }
99 
100 	A = ctx->state[0];
101 	B = ctx->state[1];
102 	C = ctx->state[2];
103 	D = ctx->state[3];
104 	E = ctx->state[4];
105 	F = ctx->state[5];
106 	G = ctx->state[6];
107 	H = ctx->state[7];
108 
109 	P(A, B, C, D, E, F, G, H, W[0], 0x428A2F98);
110 	P(H, A, B, C, D, E, F, G, W[1], 0x71374491);
111 	P(G, H, A, B, C, D, E, F, W[2], 0xB5C0FBCF);
112 	P(F, G, H, A, B, C, D, E, W[3], 0xE9B5DBA5);
113 	P(E, F, G, H, A, B, C, D, W[4], 0x3956C25B);
114 	P(D, E, F, G, H, A, B, C, W[5], 0x59F111F1);
115 	P(C, D, E, F, G, H, A, B, W[6], 0x923F82A4);
116 	P(B, C, D, E, F, G, H, A, W[7], 0xAB1C5ED5);
117 	P(A, B, C, D, E, F, G, H, W[8], 0xD807AA98);
118 	P(H, A, B, C, D, E, F, G, W[9], 0x12835B01);
119 	P(G, H, A, B, C, D, E, F, W[10], 0x243185BE);
120 	P(F, G, H, A, B, C, D, E, W[11], 0x550C7DC3);
121 	P(E, F, G, H, A, B, C, D, W[12], 0x72BE5D74);
122 	P(D, E, F, G, H, A, B, C, W[13], 0x80DEB1FE);
123 	P(C, D, E, F, G, H, A, B, W[14], 0x9BDC06A7);
124 	P(B, C, D, E, F, G, H, A, W[15], 0xC19BF174);
125 	P(A, B, C, D, E, F, G, H, R(16), 0xE49B69C1);
126 	P(H, A, B, C, D, E, F, G, R(17), 0xEFBE4786);
127 	P(G, H, A, B, C, D, E, F, R(18), 0x0FC19DC6);
128 	P(F, G, H, A, B, C, D, E, R(19), 0x240CA1CC);
129 	P(E, F, G, H, A, B, C, D, R(20), 0x2DE92C6F);
130 	P(D, E, F, G, H, A, B, C, R(21), 0x4A7484AA);
131 	P(C, D, E, F, G, H, A, B, R(22), 0x5CB0A9DC);
132 	P(B, C, D, E, F, G, H, A, R(23), 0x76F988DA);
133 	P(A, B, C, D, E, F, G, H, R(24), 0x983E5152);
134 	P(H, A, B, C, D, E, F, G, R(25), 0xA831C66D);
135 	P(G, H, A, B, C, D, E, F, R(26), 0xB00327C8);
136 	P(F, G, H, A, B, C, D, E, R(27), 0xBF597FC7);
137 	P(E, F, G, H, A, B, C, D, R(28), 0xC6E00BF3);
138 	P(D, E, F, G, H, A, B, C, R(29), 0xD5A79147);
139 	P(C, D, E, F, G, H, A, B, R(30), 0x06CA6351);
140 	P(B, C, D, E, F, G, H, A, R(31), 0x14292967);
141 	P(A, B, C, D, E, F, G, H, R(32), 0x27B70A85);
142 	P(H, A, B, C, D, E, F, G, R(33), 0x2E1B2138);
143 	P(G, H, A, B, C, D, E, F, R(34), 0x4D2C6DFC);
144 	P(F, G, H, A, B, C, D, E, R(35), 0x53380D13);
145 	P(E, F, G, H, A, B, C, D, R(36), 0x650A7354);
146 	P(D, E, F, G, H, A, B, C, R(37), 0x766A0ABB);
147 	P(C, D, E, F, G, H, A, B, R(38), 0x81C2C92E);
148 	P(B, C, D, E, F, G, H, A, R(39), 0x92722C85);
149 	P(A, B, C, D, E, F, G, H, R(40), 0xA2BFE8A1);
150 	P(H, A, B, C, D, E, F, G, R(41), 0xA81A664B);
151 	P(G, H, A, B, C, D, E, F, R(42), 0xC24B8B70);
152 	P(F, G, H, A, B, C, D, E, R(43), 0xC76C51A3);
153 	P(E, F, G, H, A, B, C, D, R(44), 0xD192E819);
154 	P(D, E, F, G, H, A, B, C, R(45), 0xD6990624);
155 	P(C, D, E, F, G, H, A, B, R(46), 0xF40E3585);
156 	P(B, C, D, E, F, G, H, A, R(47), 0x106AA070);
157 	P(A, B, C, D, E, F, G, H, R(48), 0x19A4C116);
158 	P(H, A, B, C, D, E, F, G, R(49), 0x1E376C08);
159 	P(G, H, A, B, C, D, E, F, R(50), 0x2748774C);
160 	P(F, G, H, A, B, C, D, E, R(51), 0x34B0BCB5);
161 	P(E, F, G, H, A, B, C, D, R(52), 0x391C0CB3);
162 	P(D, E, F, G, H, A, B, C, R(53), 0x4ED8AA4A);
163 	P(C, D, E, F, G, H, A, B, R(54), 0x5B9CCA4F);
164 	P(B, C, D, E, F, G, H, A, R(55), 0x682E6FF3);
165 	P(A, B, C, D, E, F, G, H, R(56), 0x748F82EE);
166 	P(H, A, B, C, D, E, F, G, R(57), 0x78A5636F);
167 	P(G, H, A, B, C, D, E, F, R(58), 0x84C87814);
168 	P(F, G, H, A, B, C, D, E, R(59), 0x8CC70208);
169 	P(E, F, G, H, A, B, C, D, R(60), 0x90BEFFFA);
170 	P(D, E, F, G, H, A, B, C, R(61), 0xA4506CEB);
171 	P(C, D, E, F, G, H, A, B, R(62), 0xBEF9A3F7);
172 	P(B, C, D, E, F, G, H, A, R(63), 0xC67178F2);
173 
174 	ctx->state[0] += A;
175 	ctx->state[1] += B;
176 	ctx->state[2] += C;
177 	ctx->state[3] += D;
178 	ctx->state[4] += E;
179 	ctx->state[5] += F;
180 	ctx->state[6] += G;
181 	ctx->state[7] += H;
182 }
183 
184 void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length)
185 {
186 	uint32_t left, fill;
187 
188 	if (!length)
189 		return;
190 
191 	left = ctx->total[0] & 0x3F;
192 	fill = 64 - left;
193 
194 	ctx->total[0] += length;
195 	ctx->total[0] &= 0xFFFFFFFF;
196 
197 	if (ctx->total[0] < length)
198 		ctx->total[1]++;
199 
200 	if (left && length >= fill) {
201 		memcpy((void *) (ctx->buffer + left), (void *) input, fill);
202 		sha256_process(ctx, ctx->buffer);
203 		length -= fill;
204 		input += fill;
205 		left = 0;
206 	}
207 
208 	while (length >= 64) {
209 		sha256_process(ctx, input);
210 		length -= 64;
211 		input += 64;
212 	}
213 
214 	if (length)
215 		memcpy((void *) (ctx->buffer + left), (void *) input, length);
216 }
217 
218 static uint8_t sha256_padding[64] = {
219 	0x80, 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 	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
222 	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
223 };
224 
225 void sha256_finish(sha256_context * ctx, uint8_t digest[32])
226 {
227 	uint32_t last, padn;
228 	uint32_t high, low;
229 	uint8_t msglen[8];
230 
231 	high = ((ctx->total[0] >> 29)
232 		| (ctx->total[1] << 3));
233 	low = (ctx->total[0] << 3);
234 
235 	PUT_UINT32_BE(high, msglen, 0);
236 	PUT_UINT32_BE(low, msglen, 4);
237 
238 	last = ctx->total[0] & 0x3F;
239 	padn = (last < 56) ? (56 - last) : (120 - last);
240 
241 	sha256_update(ctx, sha256_padding, padn);
242 	sha256_update(ctx, msglen, 8);
243 
244 	PUT_UINT32_BE(ctx->state[0], digest, 0);
245 	PUT_UINT32_BE(ctx->state[1], digest, 4);
246 	PUT_UINT32_BE(ctx->state[2], digest, 8);
247 	PUT_UINT32_BE(ctx->state[3], digest, 12);
248 	PUT_UINT32_BE(ctx->state[4], digest, 16);
249 	PUT_UINT32_BE(ctx->state[5], digest, 20);
250 	PUT_UINT32_BE(ctx->state[6], digest, 24);
251 	PUT_UINT32_BE(ctx->state[7], digest, 28);
252 }
253 
254 /*
255  * Output = SHA-256( input buffer ). Trigger the watchdog every 'chunk_sz'
256  * bytes of input processed.
257  */
258 void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
259 		unsigned char *output, unsigned int chunk_sz)
260 {
261 	sha256_context ctx;
262 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
263 	const unsigned char *end;
264 	unsigned char *curr;
265 	int chunk;
266 #endif
267 
268 	sha256_starts(&ctx);
269 
270 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
271 	curr = (unsigned char *)input;
272 	end = input + ilen;
273 	while (curr < end) {
274 		chunk = end - curr;
275 		if (chunk > chunk_sz)
276 			chunk = chunk_sz;
277 		sha256_update(&ctx, curr, chunk);
278 		curr += chunk;
279 		WATCHDOG_RESET();
280 	}
281 #else
282 	sha256_update(&ctx, input, ilen);
283 #endif
284 
285 	sha256_finish(&ctx, output);
286 }
287