xref: /openbmc/u-boot/lib/libavb/avb_sha256.c (revision cbd2fba1) 
1 // SPDX-License-Identifier: BSD-3-Clause
2 /*
3  * Copyright (C) 2005, 2007 Olivier Gay <olivier.gay@a3.epfl.ch>
4  * All rights reserved.
5  *
6  * FIPS 180-2 SHA-224/256/384/512 implementation
7  * Last update: 02/02/2007
8  * Issue date:  04/30/2005
9  */
10 
11 #include "avb_sha.h"
12 
13 #define SHFR(x, n) (x >> n)
14 #define ROTR(x, n) ((x >> n) | (x << ((sizeof(x) << 3) - n)))
15 #define ROTL(x, n) ((x << n) | (x >> ((sizeof(x) << 3) - n)))
16 #define CH(x, y, z) ((x & y) ^ (~x & z))
17 #define MAJ(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
18 
19 #define SHA256_F1(x) (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
20 #define SHA256_F2(x) (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
21 #define SHA256_F3(x) (ROTR(x, 7) ^ ROTR(x, 18) ^ SHFR(x, 3))
22 #define SHA256_F4(x) (ROTR(x, 17) ^ ROTR(x, 19) ^ SHFR(x, 10))
23 
24 #define UNPACK32(x, str)                 \
25   {                                      \
26     *((str) + 3) = (uint8_t)((x));       \
27     *((str) + 2) = (uint8_t)((x) >> 8);  \
28     *((str) + 1) = (uint8_t)((x) >> 16); \
29     *((str) + 0) = (uint8_t)((x) >> 24); \
30   }
31 
32 #define PACK32(str, x)                                                    \
33   {                                                                       \
34     *(x) = ((uint32_t) * ((str) + 3)) | ((uint32_t) * ((str) + 2) << 8) | \
35            ((uint32_t) * ((str) + 1) << 16) |                             \
36            ((uint32_t) * ((str) + 0) << 24);                              \
37   }
38 
39 /* Macros used for loops unrolling */
40 
41 #define SHA256_SCR(i) \
42   { w[i] = SHA256_F4(w[i - 2]) + w[i - 7] + SHA256_F3(w[i - 15]) + w[i - 16]; }
43 
44 #define SHA256_EXP(a, b, c, d, e, f, g, h, j)                               \
45   {                                                                         \
46     t1 = wv[h] + SHA256_F2(wv[e]) + CH(wv[e], wv[f], wv[g]) + sha256_k[j] + \
47          w[j];                                                              \
48     t2 = SHA256_F1(wv[a]) + MAJ(wv[a], wv[b], wv[c]);                       \
49     wv[d] += t1;                                                            \
50     wv[h] = t1 + t2;                                                        \
51   }
52 
53 static const uint32_t sha256_h0[8] = {0x6a09e667,
54                                       0xbb67ae85,
55                                       0x3c6ef372,
56                                       0xa54ff53a,
57                                       0x510e527f,
58                                       0x9b05688c,
59                                       0x1f83d9ab,
60                                       0x5be0cd19};
61 
62 static const uint32_t sha256_k[64] = {
63     0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1,
64     0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
65     0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786,
66     0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
67     0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,
68     0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
69     0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,
70     0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
71     0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a,
72     0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
73     0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2};
74 
75 /* SHA-256 implementation */
76 void avb_sha256_init(AvbSHA256Ctx* ctx) {
77 #ifndef UNROLL_LOOPS
78   int i;
79   for (i = 0; i < 8; i++) {
80     ctx->h[i] = sha256_h0[i];
81   }
82 #else
83   ctx->h[0] = sha256_h0[0];
84   ctx->h[1] = sha256_h0[1];
85   ctx->h[2] = sha256_h0[2];
86   ctx->h[3] = sha256_h0[3];
87   ctx->h[4] = sha256_h0[4];
88   ctx->h[5] = sha256_h0[5];
89   ctx->h[6] = sha256_h0[6];
90   ctx->h[7] = sha256_h0[7];
91 #endif /* !UNROLL_LOOPS */
92 
93   ctx->len = 0;
94   ctx->tot_len = 0;
95 }
96 
97 static void SHA256_transform(AvbSHA256Ctx* ctx,
98                              const uint8_t* message,
99                              unsigned int block_nb) {
100   uint32_t w[64];
101   uint32_t wv[8];
102   uint32_t t1, t2;
103   const unsigned char* sub_block;
104   int i;
105 
106 #ifndef UNROLL_LOOPS
107   int j;
108 #endif
109 
110   for (i = 0; i < (int)block_nb; i++) {
111     sub_block = message + (i << 6);
112 
113 #ifndef UNROLL_LOOPS
114     for (j = 0; j < 16; j++) {
115       PACK32(&sub_block[j << 2], &w[j]);
116     }
117 
118     for (j = 16; j < 64; j++) {
119       SHA256_SCR(j);
120     }
121 
122     for (j = 0; j < 8; j++) {
123       wv[j] = ctx->h[j];
124     }
125 
126     for (j = 0; j < 64; j++) {
127       t1 = wv[7] + SHA256_F2(wv[4]) + CH(wv[4], wv[5], wv[6]) + sha256_k[j] +
128            w[j];
129       t2 = SHA256_F1(wv[0]) + MAJ(wv[0], wv[1], wv[2]);
130       wv[7] = wv[6];
131       wv[6] = wv[5];
132       wv[5] = wv[4];
133       wv[4] = wv[3] + t1;
134       wv[3] = wv[2];
135       wv[2] = wv[1];
136       wv[1] = wv[0];
137       wv[0] = t1 + t2;
138     }
139 
140     for (j = 0; j < 8; j++) {
141       ctx->h[j] += wv[j];
142     }
143 #else
144     PACK32(&sub_block[0], &w[0]);
145     PACK32(&sub_block[4], &w[1]);
146     PACK32(&sub_block[8], &w[2]);
147     PACK32(&sub_block[12], &w[3]);
148     PACK32(&sub_block[16], &w[4]);
149     PACK32(&sub_block[20], &w[5]);
150     PACK32(&sub_block[24], &w[6]);
151     PACK32(&sub_block[28], &w[7]);
152     PACK32(&sub_block[32], &w[8]);
153     PACK32(&sub_block[36], &w[9]);
154     PACK32(&sub_block[40], &w[10]);
155     PACK32(&sub_block[44], &w[11]);
156     PACK32(&sub_block[48], &w[12]);
157     PACK32(&sub_block[52], &w[13]);
158     PACK32(&sub_block[56], &w[14]);
159     PACK32(&sub_block[60], &w[15]);
160 
161     SHA256_SCR(16);
162     SHA256_SCR(17);
163     SHA256_SCR(18);
164     SHA256_SCR(19);
165     SHA256_SCR(20);
166     SHA256_SCR(21);
167     SHA256_SCR(22);
168     SHA256_SCR(23);
169     SHA256_SCR(24);
170     SHA256_SCR(25);
171     SHA256_SCR(26);
172     SHA256_SCR(27);
173     SHA256_SCR(28);
174     SHA256_SCR(29);
175     SHA256_SCR(30);
176     SHA256_SCR(31);
177     SHA256_SCR(32);
178     SHA256_SCR(33);
179     SHA256_SCR(34);
180     SHA256_SCR(35);
181     SHA256_SCR(36);
182     SHA256_SCR(37);
183     SHA256_SCR(38);
184     SHA256_SCR(39);
185     SHA256_SCR(40);
186     SHA256_SCR(41);
187     SHA256_SCR(42);
188     SHA256_SCR(43);
189     SHA256_SCR(44);
190     SHA256_SCR(45);
191     SHA256_SCR(46);
192     SHA256_SCR(47);
193     SHA256_SCR(48);
194     SHA256_SCR(49);
195     SHA256_SCR(50);
196     SHA256_SCR(51);
197     SHA256_SCR(52);
198     SHA256_SCR(53);
199     SHA256_SCR(54);
200     SHA256_SCR(55);
201     SHA256_SCR(56);
202     SHA256_SCR(57);
203     SHA256_SCR(58);
204     SHA256_SCR(59);
205     SHA256_SCR(60);
206     SHA256_SCR(61);
207     SHA256_SCR(62);
208     SHA256_SCR(63);
209 
210     wv[0] = ctx->h[0];
211     wv[1] = ctx->h[1];
212     wv[2] = ctx->h[2];
213     wv[3] = ctx->h[3];
214     wv[4] = ctx->h[4];
215     wv[5] = ctx->h[5];
216     wv[6] = ctx->h[6];
217     wv[7] = ctx->h[7];
218 
219     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 0);
220     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 1);
221     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 2);
222     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 3);
223     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 4);
224     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 5);
225     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 6);
226     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 7);
227     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 8);
228     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 9);
229     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 10);
230     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 11);
231     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 12);
232     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 13);
233     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 14);
234     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 15);
235     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 16);
236     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 17);
237     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 18);
238     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 19);
239     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 20);
240     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 21);
241     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 22);
242     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 23);
243     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 24);
244     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 25);
245     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 26);
246     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 27);
247     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 28);
248     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 29);
249     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 30);
250     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 31);
251     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 32);
252     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 33);
253     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 34);
254     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 35);
255     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 36);
256     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 37);
257     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 38);
258     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 39);
259     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 40);
260     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 41);
261     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 42);
262     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 43);
263     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 44);
264     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 45);
265     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 46);
266     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 47);
267     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 48);
268     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 49);
269     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 50);
270     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 51);
271     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 52);
272     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 53);
273     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 54);
274     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 55);
275     SHA256_EXP(0, 1, 2, 3, 4, 5, 6, 7, 56);
276     SHA256_EXP(7, 0, 1, 2, 3, 4, 5, 6, 57);
277     SHA256_EXP(6, 7, 0, 1, 2, 3, 4, 5, 58);
278     SHA256_EXP(5, 6, 7, 0, 1, 2, 3, 4, 59);
279     SHA256_EXP(4, 5, 6, 7, 0, 1, 2, 3, 60);
280     SHA256_EXP(3, 4, 5, 6, 7, 0, 1, 2, 61);
281     SHA256_EXP(2, 3, 4, 5, 6, 7, 0, 1, 62);
282     SHA256_EXP(1, 2, 3, 4, 5, 6, 7, 0, 63);
283 
284     ctx->h[0] += wv[0];
285     ctx->h[1] += wv[1];
286     ctx->h[2] += wv[2];
287     ctx->h[3] += wv[3];
288     ctx->h[4] += wv[4];
289     ctx->h[5] += wv[5];
290     ctx->h[6] += wv[6];
291     ctx->h[7] += wv[7];
292 #endif /* !UNROLL_LOOPS */
293   }
294 }
295 
296 void avb_sha256_update(AvbSHA256Ctx* ctx, const uint8_t* data, uint32_t len) {
297   unsigned int block_nb;
298   unsigned int new_len, rem_len, tmp_len;
299   const uint8_t* shifted_data;
300 
301   tmp_len = AVB_SHA256_BLOCK_SIZE - ctx->len;
302   rem_len = len < tmp_len ? len : tmp_len;
303 
304   avb_memcpy(&ctx->block[ctx->len], data, rem_len);
305 
306   if (ctx->len + len < AVB_SHA256_BLOCK_SIZE) {
307     ctx->len += len;
308     return;
309   }
310 
311   new_len = len - rem_len;
312   block_nb = new_len / AVB_SHA256_BLOCK_SIZE;
313 
314   shifted_data = data + rem_len;
315 
316   SHA256_transform(ctx, ctx->block, 1);
317   SHA256_transform(ctx, shifted_data, block_nb);
318 
319   rem_len = new_len % AVB_SHA256_BLOCK_SIZE;
320 
321   avb_memcpy(ctx->block, &shifted_data[block_nb << 6], rem_len);
322 
323   ctx->len = rem_len;
324   ctx->tot_len += (block_nb + 1) << 6;
325 }
326 
327 uint8_t* avb_sha256_final(AvbSHA256Ctx* ctx) {
328   unsigned int block_nb;
329   unsigned int pm_len;
330   unsigned int len_b;
331 #ifndef UNROLL_LOOPS
332   int i;
333 #endif
334 
335   block_nb =
336       (1 + ((AVB_SHA256_BLOCK_SIZE - 9) < (ctx->len % AVB_SHA256_BLOCK_SIZE)));
337 
338   len_b = (ctx->tot_len + ctx->len) << 3;
339   pm_len = block_nb << 6;
340 
341   avb_memset(ctx->block + ctx->len, 0, pm_len - ctx->len);
342   ctx->block[ctx->len] = 0x80;
343   UNPACK32(len_b, ctx->block + pm_len - 4);
344 
345   SHA256_transform(ctx, ctx->block, block_nb);
346 
347 #ifndef UNROLL_LOOPS
348   for (i = 0; i < 8; i++) {
349     UNPACK32(ctx->h[i], &ctx->buf[i << 2]);
350   }
351 #else
352   UNPACK32(ctx->h[0], &ctx->buf[0]);
353   UNPACK32(ctx->h[1], &ctx->buf[4]);
354   UNPACK32(ctx->h[2], &ctx->buf[8]);
355   UNPACK32(ctx->h[3], &ctx->buf[12]);
356   UNPACK32(ctx->h[4], &ctx->buf[16]);
357   UNPACK32(ctx->h[5], &ctx->buf[20]);
358   UNPACK32(ctx->h[6], &ctx->buf[24]);
359   UNPACK32(ctx->h[7], &ctx->buf[28]);
360 #endif /* !UNROLL_LOOPS */
361 
362   return ctx->buf;
363 }
364