1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2011 Calxeda, Inc.
4  */
5 
6 #include <common.h>
7 #include <command.h>
8 #include <env.h>
9 #include <rand.h>
10 #include <time.h>
11 #include <uuid.h>
12 #include <linux/ctype.h>
13 #include <errno.h>
14 #include <common.h>
15 #include <asm/io.h>
16 #include <part_efi.h>
17 #include <malloc.h>
18 #include <dm/uclass.h>
19 #include <rng.h>
20 
21 /*
22  * UUID - Universally Unique IDentifier - 128 bits unique number.
23  *        There are 5 versions and one variant of UUID defined by RFC4122
24  *        specification. A UUID contains a set of fields. The set varies
25  *        depending on the version of the UUID, as shown below:
26  *        - time, MAC address(v1),
27  *        - user ID(v2),
28  *        - MD5 of name or URL(v3),
29  *        - random data(v4),
30  *        - SHA-1 of name or URL(v5),
31  *
32  * Layout of UUID:
33  * timestamp - 60-bit: time_low, time_mid, time_hi_and_version
34  * version   - 4 bit (bit 4 through 7 of the time_hi_and_version)
35  * clock seq - 14 bit: clock_seq_hi_and_reserved, clock_seq_low
36  * variant:  - bit 6 and 7 of clock_seq_hi_and_reserved
37  * node      - 48 bit
38  *
39  * source: https://www.ietf.org/rfc/rfc4122.txt
40  *
41  * UUID binary format (16 bytes):
42  *
43  * 4B-2B-2B-2B-6B (big endian - network byte order)
44  *
45  * UUID string is 36 length of characters (36 bytes):
46  *
47  * 0        9    14   19   24
48  * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
49  *    be     be   be   be       be
50  *
51  * where x is a hexadecimal character. Fields are separated by '-'s.
52  * When converting to a binary UUID, le means the field should be converted
53  * to little endian and be means it should be converted to big endian.
54  *
55  * UUID is also used as GUID (Globally Unique Identifier) with the same binary
56  * format but it differs in string format like below.
57  *
58  * GUID:
59  * 0        9    14   19   24
60  * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
61  *    le     le   le   be       be
62  *
63  * GUID is used e.g. in GPT (GUID Partition Table) as a partiions unique id.
64  */
uuid_str_valid(const char * uuid)65 int uuid_str_valid(const char *uuid)
66 {
67 	int i, valid;
68 
69 	if (uuid == NULL)
70 		return 0;
71 
72 	for (i = 0, valid = 1; uuid[i] && valid; i++) {
73 		switch (i) {
74 		case 8: case 13: case 18: case 23:
75 			valid = (uuid[i] == '-');
76 			break;
77 		default:
78 			valid = isxdigit(uuid[i]);
79 			break;
80 		}
81 	}
82 
83 	if (i != UUID_STR_LEN || !valid)
84 		return 0;
85 
86 	return 1;
87 }
88 
89 #ifdef CONFIG_PARTITION_TYPE_GUID
90 static const struct {
91 	const char *string;
92 	efi_guid_t guid;
93 } list_guid[] = {
94 	{"system",	PARTITION_SYSTEM_GUID},
95 	{"mbr",		LEGACY_MBR_PARTITION_GUID},
96 	{"msft",	PARTITION_MSFT_RESERVED_GUID},
97 	{"data",	PARTITION_BASIC_DATA_GUID},
98 	{"linux",	PARTITION_LINUX_FILE_SYSTEM_DATA_GUID},
99 	{"raid",	PARTITION_LINUX_RAID_GUID},
100 	{"swap",	PARTITION_LINUX_SWAP_GUID},
101 	{"lvm",		PARTITION_LINUX_LVM_GUID},
102 	{"u-boot-env",	PARTITION_U_BOOT_ENVIRONMENT},
103 };
104 
105 /*
106  * uuid_guid_get_bin() - this function get GUID bin for string
107  *
108  * @param guid_str - pointer to partition type string
109  * @param guid_bin - pointer to allocated array for big endian output [16B]
110  */
uuid_guid_get_bin(const char * guid_str,unsigned char * guid_bin)111 int uuid_guid_get_bin(const char *guid_str, unsigned char *guid_bin)
112 {
113 	int i;
114 
115 	for (i = 0; i < ARRAY_SIZE(list_guid); i++) {
116 		if (!strcmp(list_guid[i].string, guid_str)) {
117 			memcpy(guid_bin, &list_guid[i].guid, 16);
118 			return 0;
119 		}
120 	}
121 	return -ENODEV;
122 }
123 
124 /*
125  * uuid_guid_get_str() - this function get string for GUID.
126  *
127  * @param guid_bin - pointer to string with partition type guid [16B]
128  *
129  * Returns NULL if the type GUID is not known.
130  */
uuid_guid_get_str(const unsigned char * guid_bin)131 const char *uuid_guid_get_str(const unsigned char *guid_bin)
132 {
133 	int i;
134 
135 	for (i = 0; i < ARRAY_SIZE(list_guid); i++) {
136 		if (!memcmp(list_guid[i].guid.b, guid_bin, 16)) {
137 			return list_guid[i].string;
138 		}
139 	}
140 	return NULL;
141 }
142 #endif
143 
144 /*
145  * uuid_str_to_bin() - convert string UUID or GUID to big endian binary data.
146  *
147  * @param uuid_str - pointer to UUID or GUID string [37B] or GUID shorcut
148  * @param uuid_bin - pointer to allocated array for big endian output [16B]
149  * @str_format     - UUID string format: 0 - UUID; 1 - GUID
150  */
uuid_str_to_bin(const char * uuid_str,unsigned char * uuid_bin,int str_format)151 int uuid_str_to_bin(const char *uuid_str, unsigned char *uuid_bin,
152 		    int str_format)
153 {
154 	uint16_t tmp16;
155 	uint32_t tmp32;
156 	uint64_t tmp64;
157 
158 	if (!uuid_str_valid(uuid_str)) {
159 #ifdef CONFIG_PARTITION_TYPE_GUID
160 		if (!uuid_guid_get_bin(uuid_str, uuid_bin))
161 			return 0;
162 #endif
163 		return -EINVAL;
164 	}
165 
166 	if (str_format == UUID_STR_FORMAT_STD) {
167 		tmp32 = cpu_to_be32(simple_strtoul(uuid_str, NULL, 16));
168 		memcpy(uuid_bin, &tmp32, 4);
169 
170 		tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 9, NULL, 16));
171 		memcpy(uuid_bin + 4, &tmp16, 2);
172 
173 		tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 14, NULL, 16));
174 		memcpy(uuid_bin + 6, &tmp16, 2);
175 	} else {
176 		tmp32 = cpu_to_le32(simple_strtoul(uuid_str, NULL, 16));
177 		memcpy(uuid_bin, &tmp32, 4);
178 
179 		tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 9, NULL, 16));
180 		memcpy(uuid_bin + 4, &tmp16, 2);
181 
182 		tmp16 = cpu_to_le16(simple_strtoul(uuid_str + 14, NULL, 16));
183 		memcpy(uuid_bin + 6, &tmp16, 2);
184 	}
185 
186 	tmp16 = cpu_to_be16(simple_strtoul(uuid_str + 19, NULL, 16));
187 	memcpy(uuid_bin + 8, &tmp16, 2);
188 
189 	tmp64 = cpu_to_be64(simple_strtoull(uuid_str + 24, NULL, 16));
190 	memcpy(uuid_bin + 10, (char *)&tmp64 + 2, 6);
191 
192 	return 0;
193 }
194 
195 /*
196  * uuid_bin_to_str() - convert big endian binary data to string UUID or GUID.
197  *
198  * @param uuid_bin:	pointer to binary data of UUID (big endian) [16B]
199  * @param uuid_str:	pointer to allocated array for output string [37B]
200  * @str_format:		bit 0: 0 - UUID; 1 - GUID
201  *			bit 1: 0 - lower case; 2 - upper case
202  */
uuid_bin_to_str(const unsigned char * uuid_bin,char * uuid_str,int str_format)203 void uuid_bin_to_str(const unsigned char *uuid_bin, char *uuid_str,
204 		     int str_format)
205 {
206 	const u8 uuid_char_order[UUID_BIN_LEN] = {0, 1, 2, 3, 4, 5, 6, 7, 8,
207 						  9, 10, 11, 12, 13, 14, 15};
208 	const u8 guid_char_order[UUID_BIN_LEN] = {3, 2, 1, 0, 5, 4, 7, 6, 8,
209 						  9, 10, 11, 12, 13, 14, 15};
210 	const u8 *char_order;
211 	const char *format;
212 	int i;
213 
214 	/*
215 	 * UUID and GUID bin data - always in big endian:
216 	 * 4B-2B-2B-2B-6B
217 	 * be be be be be
218 	 */
219 	if (str_format & UUID_STR_FORMAT_GUID)
220 		char_order = guid_char_order;
221 	else
222 		char_order = uuid_char_order;
223 	if (str_format & UUID_STR_UPPER_CASE)
224 		format = "%02X";
225 	else
226 		format = "%02x";
227 
228 	for (i = 0; i < 16; i++) {
229 		sprintf(uuid_str, format, uuid_bin[char_order[i]]);
230 		uuid_str += 2;
231 		switch (i) {
232 		case 3:
233 		case 5:
234 		case 7:
235 		case 9:
236 			*uuid_str++ = '-';
237 			break;
238 		}
239 	}
240 }
241 
242 /*
243  * gen_rand_uuid() - this function generates a random binary UUID version 4.
244  *                   In this version all fields beside 4 bits of version and
245  *                   2 bits of variant are randomly generated.
246  *
247  * @param uuid_bin - pointer to allocated array [16B]. Output is in big endian.
248 */
249 #if defined(CONFIG_RANDOM_UUID) || defined(CONFIG_CMD_UUID)
gen_rand_uuid(unsigned char * uuid_bin)250 void gen_rand_uuid(unsigned char *uuid_bin)
251 {
252 	u32 ptr[4];
253 	struct uuid *uuid = (struct uuid *)ptr;
254 	int i, ret;
255 	struct udevice *devp;
256 	u32 randv = 0;
257 
258 	if (IS_ENABLED(CONFIG_DM_RNG)) {
259 		ret = uclass_get_device(UCLASS_RNG, 0, &devp);
260 		if (ret) {
261 			ret = dm_rng_read(devp, &randv, sizeof(randv));
262 			if (ret < 0)
263 				randv = 0;
264 		}
265 	}
266 	if (randv)
267 		srand(randv);
268 	else
269 		srand(get_ticks() + rand());
270 
271 	/* Set all fields randomly */
272 	for (i = 0; i < 4; i++)
273 		ptr[i] = rand();
274 
275 	clrsetbits_be16(&uuid->time_hi_and_version,
276 			UUID_VERSION_MASK,
277 			UUID_VERSION << UUID_VERSION_SHIFT);
278 
279 	clrsetbits_8(&uuid->clock_seq_hi_and_reserved,
280 		     UUID_VARIANT_MASK,
281 		     UUID_VARIANT << UUID_VARIANT_SHIFT);
282 
283 	memcpy(uuid_bin, uuid, 16);
284 }
285 
286 /*
287  * gen_rand_uuid_str() - this function generates UUID v4 (random) in two string
288  *                       formats UUID or GUID.
289  *
290  * @param uuid_str - pointer to allocated array [37B].
291  * @param          - uuid output type: UUID - 0, GUID - 1
292  */
gen_rand_uuid_str(char * uuid_str,int str_format)293 void gen_rand_uuid_str(char *uuid_str, int str_format)
294 {
295 	unsigned char uuid_bin[UUID_BIN_LEN];
296 
297 	/* Generate UUID (big endian) */
298 	gen_rand_uuid(uuid_bin);
299 
300 	/* Convert UUID bin to UUID or GUID formated STRING  */
301 	uuid_bin_to_str(uuid_bin, uuid_str, str_format);
302 }
303 
304 #if !defined(CONFIG_SPL_BUILD) && defined(CONFIG_CMD_UUID)
do_uuid(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])305 int do_uuid(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
306 {
307 	char uuid[UUID_STR_LEN + 1];
308 	int str_format;
309 
310 	if (!strcmp(argv[0], "uuid"))
311 		str_format = UUID_STR_FORMAT_STD;
312 	else
313 		str_format = UUID_STR_FORMAT_GUID;
314 
315 	if (argc > 2)
316 		return CMD_RET_USAGE;
317 
318 	gen_rand_uuid_str(uuid, str_format);
319 
320 	if (argc == 1)
321 		printf("%s\n", uuid);
322 	else
323 		env_set(argv[1], uuid);
324 
325 	return CMD_RET_SUCCESS;
326 }
327 
328 U_BOOT_CMD(uuid, CONFIG_SYS_MAXARGS, 1, do_uuid,
329 	   "UUID - generate random Universally Unique Identifier",
330 	   "[<varname>]\n"
331 	   "Argument:\n"
332 	   "varname: for set result in a environment variable\n"
333 	   "e.g. uuid uuid_env"
334 );
335 
336 U_BOOT_CMD(guid, CONFIG_SYS_MAXARGS, 1, do_uuid,
337 	   "GUID - generate Globally Unique Identifier based on random UUID",
338 	   "[<varname>]\n"
339 	   "Argument:\n"
340 	   "varname: for set result in a environment variable\n"
341 	   "e.g. guid guid_env"
342 );
343 #endif /* CONFIG_CMD_UUID */
344 #endif /* CONFIG_RANDOM_UUID || CONFIG_CMD_UUID */
345