xref: /openbmc/u-boot/common/hash.c (revision 412ae53a) 
1 /*
2  * Copyright (c) 2012 The Chromium OS Authors.
3  *
4  * (C) Copyright 2011
5  * Joe Hershberger, National Instruments, joe.hershberger@ni.com
6  *
7  * (C) Copyright 2000
8  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
9  *
10  * SPDX-License-Identifier:	GPL-2.0+
11  */
12 
13 #ifndef USE_HOSTCC
14 #include <common.h>
15 #include <command.h>
16 #include <malloc.h>
17 #include <hw_sha.h>
18 #include <asm/io.h>
19 #include <asm/errno.h>
20 #else
21 #include "mkimage.h"
22 #include <time.h>
23 #include <image.h>
24 #endif /* !USE_HOSTCC*/
25 
26 #include <hash.h>
27 #include <u-boot/crc.h>
28 #include <u-boot/sha1.h>
29 #include <u-boot/sha256.h>
30 #include <u-boot/md5.h>
31 
32 #ifdef CONFIG_SHA1
33 static int hash_init_sha1(struct hash_algo *algo, void **ctxp)
34 {
35 	sha1_context *ctx = malloc(sizeof(sha1_context));
36 	sha1_starts(ctx);
37 	*ctxp = ctx;
38 	return 0;
39 }
40 
41 static int hash_update_sha1(struct hash_algo *algo, void *ctx, const void *buf,
42 			    unsigned int size, int is_last)
43 {
44 	sha1_update((sha1_context *)ctx, buf, size);
45 	return 0;
46 }
47 
48 static int hash_finish_sha1(struct hash_algo *algo, void *ctx, void *dest_buf,
49 			    int size)
50 {
51 	if (size < algo->digest_size)
52 		return -1;
53 
54 	sha1_finish((sha1_context *)ctx, dest_buf);
55 	free(ctx);
56 	return 0;
57 }
58 #endif
59 
60 #ifdef CONFIG_SHA256
61 static int hash_init_sha256(struct hash_algo *algo, void **ctxp)
62 {
63 	sha256_context *ctx = malloc(sizeof(sha256_context));
64 	sha256_starts(ctx);
65 	*ctxp = ctx;
66 	return 0;
67 }
68 
69 static int hash_update_sha256(struct hash_algo *algo, void *ctx,
70 			      const void *buf, unsigned int size, int is_last)
71 {
72 	sha256_update((sha256_context *)ctx, buf, size);
73 	return 0;
74 }
75 
76 static int hash_finish_sha256(struct hash_algo *algo, void *ctx, void
77 			      *dest_buf, int size)
78 {
79 	if (size < algo->digest_size)
80 		return -1;
81 
82 	sha256_finish((sha256_context *)ctx, dest_buf);
83 	free(ctx);
84 	return 0;
85 }
86 #endif
87 
88 static int hash_init_crc32(struct hash_algo *algo, void **ctxp)
89 {
90 	uint32_t *ctx = malloc(sizeof(uint32_t));
91 	*ctx = 0;
92 	*ctxp = ctx;
93 	return 0;
94 }
95 
96 static int hash_update_crc32(struct hash_algo *algo, void *ctx,
97 			     const void *buf, unsigned int size, int is_last)
98 {
99 	*((uint32_t *)ctx) = crc32(*((uint32_t *)ctx), buf, size);
100 	return 0;
101 }
102 
103 static int hash_finish_crc32(struct hash_algo *algo, void *ctx, void *dest_buf,
104 			     int size)
105 {
106 	if (size < algo->digest_size)
107 		return -1;
108 
109 	*((uint32_t *)dest_buf) = *((uint32_t *)ctx);
110 	free(ctx);
111 	return 0;
112 }
113 
114 /*
115  * These are the hash algorithms we support. Chips which support accelerated
116  * crypto could perhaps add named version of these algorithms here. Note that
117  * algorithm names must be in lower case.
118  */
119 static struct hash_algo hash_algo[] = {
120 	/*
121 	 * CONFIG_SHA_HW_ACCEL is defined if hardware acceleration is
122 	 * available.
123 	 */
124 #ifdef CONFIG_SHA_HW_ACCEL
125 	{
126 		"sha1",
127 		SHA1_SUM_LEN,
128 		hw_sha1,
129 		CHUNKSZ_SHA1,
130 #ifdef CONFIG_SHA_PROG_HW_ACCEL
131 		hw_sha_init,
132 		hw_sha_update,
133 		hw_sha_finish,
134 #endif
135 	}, {
136 		"sha256",
137 		SHA256_SUM_LEN,
138 		hw_sha256,
139 		CHUNKSZ_SHA256,
140 #ifdef CONFIG_SHA_PROG_HW_ACCEL
141 		hw_sha_init,
142 		hw_sha_update,
143 		hw_sha_finish,
144 #endif
145 	},
146 #endif
147 #ifdef CONFIG_SHA1
148 	{
149 		"sha1",
150 		SHA1_SUM_LEN,
151 		sha1_csum_wd,
152 		CHUNKSZ_SHA1,
153 		hash_init_sha1,
154 		hash_update_sha1,
155 		hash_finish_sha1,
156 	},
157 #endif
158 #ifdef CONFIG_SHA256
159 	{
160 		"sha256",
161 		SHA256_SUM_LEN,
162 		sha256_csum_wd,
163 		CHUNKSZ_SHA256,
164 		hash_init_sha256,
165 		hash_update_sha256,
166 		hash_finish_sha256,
167 	},
168 #endif
169 	{
170 		"crc32",
171 		4,
172 		crc32_wd_buf,
173 		CHUNKSZ_CRC32,
174 		hash_init_crc32,
175 		hash_update_crc32,
176 		hash_finish_crc32,
177 	},
178 };
179 
180 #if defined(CONFIG_SHA256) || defined(CONFIG_CMD_SHA1SUM)
181 #define MULTI_HASH
182 #endif
183 
184 #if defined(CONFIG_HASH_VERIFY) || defined(CONFIG_CMD_HASH)
185 #define MULTI_HASH
186 #endif
187 
188 /* Try to minimize code size for boards that don't want much hashing */
189 #ifdef MULTI_HASH
190 #define multi_hash()	1
191 #else
192 #define multi_hash()	0
193 #endif
194 
195 int hash_lookup_algo(const char *algo_name, struct hash_algo **algop)
196 {
197 	int i;
198 
199 	for (i = 0; i < ARRAY_SIZE(hash_algo); i++) {
200 		if (!strcmp(algo_name, hash_algo[i].name)) {
201 			*algop = &hash_algo[i];
202 			return 0;
203 		}
204 	}
205 
206 	debug("Unknown hash algorithm '%s'\n", algo_name);
207 	return -EPROTONOSUPPORT;
208 }
209 
210 int hash_progressive_lookup_algo(const char *algo_name,
211 				 struct hash_algo **algop)
212 {
213 	int i;
214 
215 	for (i = 0; i < ARRAY_SIZE(hash_algo); i++) {
216 		if (!strcmp(algo_name, hash_algo[i].name)) {
217 			if (hash_algo[i].hash_init) {
218 				*algop = &hash_algo[i];
219 				return 0;
220 			}
221 		}
222 	}
223 
224 	debug("Unknown hash algorithm '%s'\n", algo_name);
225 	return -EPROTONOSUPPORT;
226 }
227 
228 #ifndef USE_HOSTCC
229 /**
230  * store_result: Store the resulting sum to an address or variable
231  *
232  * @algo:		Hash algorithm being used
233  * @sum:		Hash digest (algo->digest_size bytes)
234  * @dest:		Destination, interpreted as a hex address if it starts
235  *			with * (or allow_env_vars is 0) or otherwise as an
236  *			environment variable.
237  * @allow_env_vars:	non-zero to permit storing the result to an
238  *			variable environment
239  */
240 static void store_result(struct hash_algo *algo, const uint8_t *sum,
241 			 const char *dest, int allow_env_vars)
242 {
243 	unsigned int i;
244 	int env_var = 0;
245 
246 	/*
247 	 * If environment variables are allowed, then we assume that 'dest'
248 	 * is an environment variable, unless it starts with *, in which
249 	 * case we assume it is an address. If not allowed, it is always an
250 	 * address. This is to support the crc32 command.
251 	 */
252 	if (allow_env_vars) {
253 		if (*dest == '*')
254 			dest++;
255 		else
256 			env_var = 1;
257 	}
258 
259 	if (env_var) {
260 		char str_output[HASH_MAX_DIGEST_SIZE * 2 + 1];
261 		char *str_ptr = str_output;
262 
263 		for (i = 0; i < algo->digest_size; i++) {
264 			sprintf(str_ptr, "%02x", sum[i]);
265 			str_ptr += 2;
266 		}
267 		*str_ptr = '\0';
268 		setenv(dest, str_output);
269 	} else {
270 		ulong addr;
271 		void *buf;
272 
273 		addr = simple_strtoul(dest, NULL, 16);
274 		buf = map_sysmem(addr, algo->digest_size);
275 		memcpy(buf, sum, algo->digest_size);
276 		unmap_sysmem(buf);
277 	}
278 }
279 
280 /**
281  * parse_verify_sum: Parse a hash verification parameter
282  *
283  * @algo:		Hash algorithm being used
284  * @verify_str:		Argument to parse. If it starts with * then it is
285  *			interpreted as a hex address containing the hash.
286  *			If the length is exactly the right number of hex digits
287  *			for the digest size, then we assume it is a hex digest.
288  *			Otherwise we assume it is an environment variable, and
289  *			look up its value (it must contain a hex digest).
290  * @vsum:		Returns binary digest value (algo->digest_size bytes)
291  * @allow_env_vars:	non-zero to permit storing the result to an environment
292  *			variable. If 0 then verify_str is assumed to be an
293  *			address, and the * prefix is not expected.
294  * @return 0 if ok, non-zero on error
295  */
296 static int parse_verify_sum(struct hash_algo *algo, char *verify_str,
297 			    uint8_t *vsum, int allow_env_vars)
298 {
299 	int env_var = 0;
300 
301 	/* See comment above in store_result() */
302 	if (allow_env_vars) {
303 		if (*verify_str == '*')
304 			verify_str++;
305 		else
306 			env_var = 1;
307 	}
308 
309 	if (!env_var) {
310 		ulong addr;
311 		void *buf;
312 
313 		addr = simple_strtoul(verify_str, NULL, 16);
314 		buf = map_sysmem(addr, algo->digest_size);
315 		memcpy(vsum, buf, algo->digest_size);
316 	} else {
317 		unsigned int i;
318 		char *vsum_str;
319 		int digits = algo->digest_size * 2;
320 
321 		/*
322 		 * As with the original code from sha1sum.c, we assume that a
323 		 * string which matches the digest size exactly is a hex
324 		 * string and not an environment variable.
325 		 */
326 		if (strlen(verify_str) == digits)
327 			vsum_str = verify_str;
328 		else {
329 			vsum_str = getenv(verify_str);
330 			if (vsum_str == NULL || strlen(vsum_str) != digits) {
331 				printf("Expected %d hex digits in env var\n",
332 				       digits);
333 				return 1;
334 			}
335 		}
336 
337 		for (i = 0; i < algo->digest_size; i++) {
338 			char *nullp = vsum_str + (i + 1) * 2;
339 			char end = *nullp;
340 
341 			*nullp = '\0';
342 			vsum[i] = simple_strtoul(vsum_str + (i * 2), NULL, 16);
343 			*nullp = end;
344 		}
345 	}
346 	return 0;
347 }
348 
349 void hash_show(struct hash_algo *algo, ulong addr, ulong len, uint8_t *output)
350 {
351 	int i;
352 
353 	printf("%s for %08lx ... %08lx ==> ", algo->name, addr, addr + len - 1);
354 	for (i = 0; i < algo->digest_size; i++)
355 		printf("%02x", output[i]);
356 }
357 
358 int hash_block(const char *algo_name, const void *data, unsigned int len,
359 	       uint8_t *output, int *output_size)
360 {
361 	struct hash_algo *algo;
362 	int ret;
363 
364 	ret = hash_lookup_algo(algo_name, &algo);
365 	if (ret)
366 		return ret;
367 
368 	if (output_size && *output_size < algo->digest_size) {
369 		debug("Output buffer size %d too small (need %d bytes)",
370 		      *output_size, algo->digest_size);
371 		return -ENOSPC;
372 	}
373 	if (output_size)
374 		*output_size = algo->digest_size;
375 	algo->hash_func_ws(data, len, output, algo->chunk_size);
376 
377 	return 0;
378 }
379 
380 int hash_command(const char *algo_name, int flags, cmd_tbl_t *cmdtp, int flag,
381 		 int argc, char * const argv[])
382 {
383 	ulong addr, len;
384 
385 	if ((argc < 2) || ((flags & HASH_FLAG_VERIFY) && (argc < 3)))
386 		return CMD_RET_USAGE;
387 
388 	addr = simple_strtoul(*argv++, NULL, 16);
389 	len = simple_strtoul(*argv++, NULL, 16);
390 
391 	if (multi_hash()) {
392 		struct hash_algo *algo;
393 		uint8_t output[HASH_MAX_DIGEST_SIZE];
394 		uint8_t vsum[HASH_MAX_DIGEST_SIZE];
395 		void *buf;
396 
397 		if (hash_lookup_algo(algo_name, &algo)) {
398 			printf("Unknown hash algorithm '%s'\n", algo_name);
399 			return CMD_RET_USAGE;
400 		}
401 		argc -= 2;
402 
403 		if (algo->digest_size > HASH_MAX_DIGEST_SIZE) {
404 			puts("HASH_MAX_DIGEST_SIZE exceeded\n");
405 			return 1;
406 		}
407 
408 		buf = map_sysmem(addr, len);
409 		algo->hash_func_ws(buf, len, output, algo->chunk_size);
410 		unmap_sysmem(buf);
411 
412 		/* Try to avoid code bloat when verify is not needed */
413 #ifdef CONFIG_HASH_VERIFY
414 		if (flags & HASH_FLAG_VERIFY) {
415 #else
416 		if (0) {
417 #endif
418 			if (parse_verify_sum(algo, *argv, vsum,
419 					flags & HASH_FLAG_ENV)) {
420 				printf("ERROR: %s does not contain a valid "
421 					"%s sum\n", *argv, algo->name);
422 				return 1;
423 			}
424 			if (memcmp(output, vsum, algo->digest_size) != 0) {
425 				int i;
426 
427 				hash_show(algo, addr, len, output);
428 				printf(" != ");
429 				for (i = 0; i < algo->digest_size; i++)
430 					printf("%02x", vsum[i]);
431 				puts(" ** ERROR **\n");
432 				return 1;
433 			}
434 		} else {
435 			hash_show(algo, addr, len, output);
436 			printf("\n");
437 
438 			if (argc) {
439 				store_result(algo, output, *argv,
440 					flags & HASH_FLAG_ENV);
441 			}
442 		}
443 
444 	/* Horrible code size hack for boards that just want crc32 */
445 	} else {
446 		ulong crc;
447 		ulong *ptr;
448 
449 		crc = crc32_wd(0, (const uchar *)addr, len, CHUNKSZ_CRC32);
450 
451 		printf("CRC32 for %08lx ... %08lx ==> %08lx\n",
452 				addr, addr + len - 1, crc);
453 
454 		if (argc >= 3) {
455 			ptr = (ulong *)simple_strtoul(argv[0], NULL, 16);
456 			*ptr = crc;
457 		}
458 	}
459 
460 	return 0;
461 }
462 #endif
463