xref: /rk3399_rockchip-uboot/common/hash.c (revision bd091b67d0ef2959ed0ff2aa6575ddb0d21c1f71)
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  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of
13  * the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23  * MA 02111-1307 USA
24  */
25 
26 #include <common.h>
27 #include <command.h>
28 #include <hash.h>
29 #include <sha1.h>
30 #include <sha256.h>
31 #include <asm/io.h>
32 
33 /*
34  * These are the hash algorithms we support. Chips which support accelerated
35  * crypto could perhaps add named version of these algorithms here.
36  */
37 static struct hash_algo hash_algo[] = {
38 	/*
39 	 * This is CONFIG_CMD_SHA1SUM instead of CONFIG_SHA1 since otherwise
40 	 * it bloats the code for boards which use SHA1 but not the 'hash'
41 	 * or 'sha1sum' commands.
42 	 */
43 #ifdef CONFIG_CMD_SHA1SUM
44 	{
45 		"SHA1",
46 		SHA1_SUM_LEN,
47 		sha1_csum_wd,
48 		CHUNKSZ_SHA1,
49 	},
50 #define MULTI_HASH
51 #endif
52 #ifdef CONFIG_SHA256
53 	{
54 		"SHA256",
55 		SHA256_SUM_LEN,
56 		sha256_csum_wd,
57 		CHUNKSZ_SHA256,
58 	},
59 #define MULTI_HASH
60 #endif
61 	{
62 		"CRC32",
63 		4,
64 		crc32_wd_buf,
65 		CHUNKSZ_CRC32,
66 	},
67 };
68 
69 #if defined(CONFIG_HASH_VERIFY) || defined(CONFIG_CMD_HASH)
70 #define MULTI_HASH
71 #endif
72 
73 /* Try to minimize code size for boards that don't want much hashing */
74 #ifdef MULTI_HASH
75 #define multi_hash()	1
76 #else
77 #define multi_hash()	0
78 #endif
79 
80 /**
81  * store_result: Store the resulting sum to an address or variable
82  *
83  * @algo:		Hash algorithm being used
84  * @sum:		Hash digest (algo->digest_size bytes)
85  * @dest:		Destination, interpreted as a hex address if it starts
86  *			with * (or allow_env_vars is 0) or otherwise as an
87  *			environment variable.
88  * @allow_env_vars:	non-zero to permit storing the result to an
89  *			variable environment
90  */
91 static void store_result(struct hash_algo *algo, const u8 *sum,
92 			 const char *dest, int allow_env_vars)
93 {
94 	unsigned int i;
95 	int env_var = 0;
96 
97 	/*
98 	 * If environment variables are allowed, then we assume that 'dest'
99 	 * is an environment variable, unless it starts with *, in which
100 	 * case we assume it is an address. If not allowed, it is always an
101 	 * address. This is to support the crc32 command.
102 	 */
103 	if (allow_env_vars) {
104 		if (*dest == '*')
105 			dest++;
106 		else
107 			env_var = 1;
108 	}
109 
110 	if (env_var) {
111 		char str_output[HASH_MAX_DIGEST_SIZE * 2 + 1];
112 		char *str_ptr = str_output;
113 
114 		for (i = 0; i < algo->digest_size; i++) {
115 			sprintf(str_ptr, "%02x", sum[i]);
116 			str_ptr += 2;
117 		}
118 		str_ptr = '\0';
119 		setenv(dest, str_output);
120 	} else {
121 		ulong addr;
122 		void *buf;
123 
124 		addr = simple_strtoul(dest, NULL, 16);
125 		buf = map_sysmem(addr, algo->digest_size);
126 		memcpy(buf, sum, algo->digest_size);
127 		unmap_sysmem(buf);
128 	}
129 }
130 
131 /**
132  * parse_verify_sum: Parse a hash verification parameter
133  *
134  * @algo:		Hash algorithm being used
135  * @verify_str:		Argument to parse. If it starts with * then it is
136  *			interpreted as a hex address containing the hash.
137  *			If the length is exactly the right number of hex digits
138  *			for the digest size, then we assume it is a hex digest.
139  *			Otherwise we assume it is an environment variable, and
140  *			look up its value (it must contain a hex digest).
141  * @vsum:		Returns binary digest value (algo->digest_size bytes)
142  * @allow_env_vars:	non-zero to permit storing the result to an environment
143  *			variable. If 0 then verify_str is assumed to be an
144  *			address, and the * prefix is not expected.
145  * @return 0 if ok, non-zero on error
146  */
147 static int parse_verify_sum(struct hash_algo *algo, char *verify_str, u8 *vsum,
148 			    int allow_env_vars)
149 {
150 	int env_var = 0;
151 
152 	/* See comment above in store_result() */
153 	if (allow_env_vars) {
154 		if (*verify_str == '*')
155 			verify_str++;
156 		else
157 			env_var = 1;
158 	}
159 
160 	if (env_var) {
161 		ulong addr;
162 		void *buf;
163 
164 		addr = simple_strtoul(verify_str, NULL, 16);
165 		buf = map_sysmem(addr, algo->digest_size);
166 		memcpy(vsum, buf, algo->digest_size);
167 	} else {
168 		unsigned int i;
169 		char *vsum_str;
170 		int digits = algo->digest_size * 2;
171 
172 		/*
173 		 * As with the original code from sha1sum.c, we assume that a
174 		 * string which matches the digest size exactly is a hex
175 		 * string and not an environment variable.
176 		 */
177 		if (strlen(verify_str) == digits)
178 			vsum_str = verify_str;
179 		else {
180 			vsum_str = getenv(verify_str);
181 			if (vsum_str == NULL || strlen(vsum_str) != digits) {
182 				printf("Expected %d hex digits in env var\n",
183 				       digits);
184 				return 1;
185 			}
186 		}
187 
188 		for (i = 0; i < algo->digest_size; i++) {
189 			char *nullp = vsum_str + (i + 1) * 2;
190 			char end = *nullp;
191 
192 			*nullp = '\0';
193 			vsum[i] = simple_strtoul(vsum_str + (i * 2), NULL, 16);
194 			*nullp = end;
195 		}
196 	}
197 	return 0;
198 }
199 
200 static struct hash_algo *find_hash_algo(const char *name)
201 {
202 	int i;
203 
204 	for (i = 0; i < ARRAY_SIZE(hash_algo); i++) {
205 		if (!strcasecmp(name, hash_algo[i].name))
206 			return &hash_algo[i];
207 	}
208 
209 	return NULL;
210 }
211 
212 static void show_hash(struct hash_algo *algo, ulong addr, ulong len,
213 		      u8 *output)
214 {
215 	int i;
216 
217 	printf("%s for %08lx ... %08lx ==> ", algo->name, addr, addr + len - 1);
218 	for (i = 0; i < algo->digest_size; i++)
219 		printf("%02x", output[i]);
220 }
221 
222 int hash_command(const char *algo_name, int flags, cmd_tbl_t *cmdtp, int flag,
223 		 int argc, char * const argv[])
224 {
225 	ulong addr, len;
226 
227 	if (argc < 2)
228 		return CMD_RET_USAGE;
229 
230 	addr = simple_strtoul(*argv++, NULL, 16);
231 	len = simple_strtoul(*argv++, NULL, 16);
232 
233 	if (multi_hash()) {
234 		struct hash_algo *algo;
235 		u8 output[HASH_MAX_DIGEST_SIZE];
236 		u8 vsum[HASH_MAX_DIGEST_SIZE];
237 		void *buf;
238 
239 		algo = find_hash_algo(algo_name);
240 		if (!algo) {
241 			printf("Unknown hash algorithm '%s'\n", algo_name);
242 			return CMD_RET_USAGE;
243 		}
244 		argc -= 2;
245 
246 		if (algo->digest_size > HASH_MAX_DIGEST_SIZE) {
247 			puts("HASH_MAX_DIGEST_SIZE exceeded\n");
248 			return 1;
249 		}
250 
251 		buf = map_sysmem(addr, len);
252 		algo->hash_func_ws(buf, len, output, algo->chunk_size);
253 		unmap_sysmem(buf);
254 
255 		/* Try to avoid code bloat when verify is not needed */
256 #ifdef CONFIG_HASH_VERIFY
257 		if (flags & HASH_FLAG_VERIFY) {
258 #else
259 		if (0) {
260 #endif
261 			if (!argc)
262 				return CMD_RET_USAGE;
263 			if (parse_verify_sum(algo, *argv, vsum,
264 					flags & HASH_FLAG_ENV)) {
265 				printf("ERROR: %s does not contain a valid "
266 					"%s sum\n", *argv, algo->name);
267 				return 1;
268 			}
269 			if (memcmp(output, vsum, algo->digest_size) != 0) {
270 				int i;
271 
272 				show_hash(algo, addr, len, output);
273 				printf(" != ");
274 				for (i = 0; i < algo->digest_size; i++)
275 					printf("%02x", vsum[i]);
276 				puts(" ** ERROR **\n");
277 				return 1;
278 			}
279 		} else {
280 			show_hash(algo, addr, len, output);
281 			printf("\n");
282 
283 			if (argc) {
284 				store_result(algo, output, *argv,
285 					flags & HASH_FLAG_ENV);
286 			}
287 		}
288 
289 	/* Horrible code size hack for boards that just want crc32 */
290 	} else {
291 		ulong crc;
292 		ulong *ptr;
293 
294 		crc = crc32_wd(0, (const uchar *)addr, len, CHUNKSZ_CRC32);
295 
296 		printf("CRC32 for %08lx ... %08lx ==> %08lx\n",
297 				addr, addr + len - 1, crc);
298 
299 		if (argc > 3) {
300 			ptr = (ulong *)simple_strtoul(argv[3], NULL, 16);
301 			*ptr = crc;
302 		}
303 	}
304 
305 	return 0;
306 }
307