xref: /openbmc/u-boot/disk/part_efi.c (revision 9017d932)
1 /*
2  * Copyright (C) 2008 RuggedCom, Inc.
3  * Richard Retanubun <RichardRetanubun@RuggedCom.com>
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 /*
25  * Problems with CONFIG_SYS_64BIT_LBA:
26  *
27  * struct disk_partition.start in include/part.h is sized as ulong.
28  * When CONFIG_SYS_64BIT_LBA is activated, lbaint_t changes from ulong to uint64_t.
29  * For now, it is cast back to ulong at assignment.
30  *
31  * This limits the maximum size of addressable storage to < 2 Terra Bytes
32  */
33 #include <common.h>
34 #include <command.h>
35 #include <ide.h>
36 #include <malloc.h>
37 #include "part_efi.h"
38 
39 #if defined(CONFIG_CMD_IDE) || \
40     defined(CONFIG_CMD_SATA) || \
41     defined(CONFIG_CMD_SCSI) || \
42     defined(CONFIG_CMD_USB) || \
43     defined(CONFIG_MMC) || \
44     defined(CONFIG_SYSTEMACE)
45 
46 /* Convert char[2] in little endian format to the host format integer
47  */
48 static inline unsigned short le16_to_int(unsigned char *le16)
49 {
50 	return ((le16[1] << 8) + le16[0]);
51 }
52 
53 /* Convert char[4] in little endian format to the host format integer
54  */
55 static inline unsigned long le32_to_int(unsigned char *le32)
56 {
57 	return ((le32[3] << 24) + (le32[2] << 16) + (le32[1] << 8) + le32[0]);
58 }
59 
60 /* Convert char[8] in little endian format to the host format integer
61  */
62 static inline unsigned long long le64_to_int(unsigned char *le64)
63 {
64 	return (((unsigned long long)le64[7] << 56) +
65 		((unsigned long long)le64[6] << 48) +
66 		((unsigned long long)le64[5] << 40) +
67 		((unsigned long long)le64[4] << 32) +
68 		((unsigned long long)le64[3] << 24) +
69 		((unsigned long long)le64[2] << 16) +
70 		((unsigned long long)le64[1] << 8) +
71 		(unsigned long long)le64[0]);
72 }
73 
74 /**
75  * efi_crc32() - EFI version of crc32 function
76  * @buf: buffer to calculate crc32 of
77  * @len - length of buf
78  *
79  * Description: Returns EFI-style CRC32 value for @buf
80  */
81 static inline unsigned long efi_crc32(const void *buf, unsigned long len)
82 {
83 	return crc32(0, buf, len);
84 }
85 
86 /*
87  * Private function prototypes
88  */
89 
90 static int pmbr_part_valid(struct partition *part);
91 static int is_pmbr_valid(legacy_mbr * mbr);
92 
93 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
94 				gpt_header * pgpt_head, gpt_entry ** pgpt_pte);
95 
96 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
97 				gpt_header * pgpt_head);
98 
99 static int is_pte_valid(gpt_entry * pte);
100 
101 /*
102  * Public Functions (include/part.h)
103  */
104 
105 void print_part_efi(block_dev_desc_t * dev_desc)
106 {
107 	gpt_header gpt_head;
108 	gpt_entry **pgpt_pte = NULL;
109 	int i = 0;
110 
111 	if (!dev_desc) {
112 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
113 		return;
114 	}
115 	/* This function validates AND fills in the GPT header and PTE */
116 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
117 			 &(gpt_head), pgpt_pte) != 1) {
118 		printf("%s: *** ERROR: Invalid GPT ***\n", __FUNCTION__);
119 		return;
120 	}
121 
122 	debug("%s: gpt-entry at 0x%08X\n", __FUNCTION__, (unsigned int)*pgpt_pte);
123 
124 	printf("Part  Start LBA  End LBA\n");
125 	for (i = 0; i < le32_to_int(gpt_head.num_partition_entries); i++) {
126 
127 		if (is_pte_valid(&(*pgpt_pte)[i])) {
128 			printf("%s%d  0x%llX    0x%llX\n", GPT_ENTRY_NAME,
129 				(i + 1),
130 				le64_to_int((*pgpt_pte)[i].starting_lba),
131 				le64_to_int((*pgpt_pte)[i].ending_lba));
132 		} else {
133 			break;	/* Stop at the first non valid PTE */
134 		}
135 	}
136 
137 	/* Remember to free pte */
138 	if (*pgpt_pte != NULL) {
139 		debug("%s: Freeing pgpt_pte\n", __FUNCTION__);
140 		free(*pgpt_pte);
141 	}
142 	return;
143 }
144 
145 int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
146 				disk_partition_t * info)
147 {
148 	gpt_header gpt_head;
149 	gpt_entry **pgpt_pte = NULL;
150 
151 	/* "part" argument must be at least 1 */
152 	if (!dev_desc || !info || part < 1) {
153 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
154 		return -1;
155 	}
156 
157 	/* This function validates AND fills in the GPT header and PTE */
158 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
159 			&(gpt_head), pgpt_pte) != 1) {
160 		printf("%s: *** ERROR: Invalid GPT ***\n", __FUNCTION__);
161 		return -1;
162 	}
163 
164 	/* The ulong casting limits the maximum disk size to 2 TB */
165 	info->start = (ulong) le64_to_int((*pgpt_pte)[part - 1].starting_lba);
166 	/* The ending LBA is inclusive, to calculate size, add 1 to it */
167 	info->size = ((ulong)le64_to_int((*pgpt_pte)[part - 1].ending_lba) + 1)
168 		     - info->start;
169 	info->blksz = GPT_BLOCK_SIZE;
170 
171 	sprintf((char *)info->name, "%s%d\n", GPT_ENTRY_NAME, part);
172 	sprintf((char *)info->type, "U-Boot");
173 
174 	debug("%s: start 0x%lX, size 0x%lX, name %s", __FUNCTION__,
175 		info->start, info->size, info->name);
176 
177 	/* Remember to free pte */
178 	if (*pgpt_pte != NULL) {
179 		debug("%s: Freeing pgpt_pte\n", __FUNCTION__);
180 		free(*pgpt_pte);
181 	}
182 	return 0;
183 }
184 
185 int test_part_efi(block_dev_desc_t * dev_desc)
186 {
187 	legacy_mbr legacymbr;
188 
189 	/* Read legacy MBR from block 0 and validate it */
190 	if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *) & legacymbr) != 1)
191 		|| (is_pmbr_valid(&legacymbr) != 1)) {
192 		return -1;
193 	}
194 	return 0;
195 }
196 
197 /*
198  * Private functions
199  */
200 /*
201  * pmbr_part_valid(): Check for EFI partition signature
202  *
203  * Returns: 1 if EFI GPT partition type is found.
204  */
205 static int pmbr_part_valid(struct partition *part)
206 {
207 	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
208 		le32_to_int(part->start_sect) == 1UL) {
209 		return 1;
210 	}
211 
212 	return 0;
213 }
214 
215 /*
216  * is_pmbr_valid(): test Protective MBR for validity
217  *
218  * Returns: 1 if PMBR is valid, 0 otherwise.
219  * Validity depends on two things:
220  *  1) MSDOS signature is in the last two bytes of the MBR
221  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
222  */
223 static int is_pmbr_valid(legacy_mbr * mbr)
224 {
225 	int i = 0;
226 
227 	if (!mbr || le16_to_int(mbr->signature) != MSDOS_MBR_SIGNATURE) {
228 		return 0;
229 	}
230 
231 	for (i = 0; i < 4; i++) {
232 		if (pmbr_part_valid(&mbr->partition_record[i])) {
233 			return 1;
234 		}
235 	}
236 	return 0;
237 }
238 
239 /**
240  * is_gpt_valid() - tests one GPT header and PTEs for validity
241  *
242  * lba is the logical block address of the GPT header to test
243  * gpt is a GPT header ptr, filled on return.
244  * ptes is a PTEs ptr, filled on return.
245  *
246  * Description: returns 1 if valid,  0 on error.
247  * If valid, returns pointers to PTEs.
248  */
249 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
250 			gpt_header * pgpt_head, gpt_entry ** pgpt_pte)
251 {
252 	unsigned char crc32_backup[4] = { 0 };
253 	unsigned long calc_crc32;
254 	unsigned long long lastlba;
255 
256 	if (!dev_desc || !pgpt_head) {
257 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
258 		return 0;
259 	}
260 
261 	/* Read GPT Header from device */
262 	if (dev_desc->block_read(dev_desc->dev, lba, 1, pgpt_head) != 1) {
263 		printf("*** ERROR: Can't read GPT header ***\n");
264 		return 0;
265 	}
266 
267 	/* Check the GPT header signature */
268 	if (le64_to_int(pgpt_head->signature) != GPT_HEADER_SIGNATURE) {
269 		printf("GUID Partition Table Header signature is wrong:"
270 			"0x%llX != 0x%llX\n",
271 			(unsigned long long)le64_to_int(pgpt_head->signature),
272 			(unsigned long long)GPT_HEADER_SIGNATURE);
273 		return 0;
274 	}
275 
276 	/* Check the GUID Partition Table CRC */
277 	memcpy(crc32_backup, pgpt_head->header_crc32, sizeof(crc32_backup));
278 	memset(pgpt_head->header_crc32, 0, sizeof(pgpt_head->header_crc32));
279 
280 	calc_crc32 = efi_crc32((const unsigned char *)pgpt_head,
281 		le32_to_int(pgpt_head->header_size));
282 
283 	memcpy(pgpt_head->header_crc32, crc32_backup, sizeof(crc32_backup));
284 
285 	if (calc_crc32 != le32_to_int(crc32_backup)) {
286 		printf("GUID Partition Table Header CRC is wrong:"
287 			"0x%08lX != 0x%08lX\n",
288 			le32_to_int(crc32_backup), calc_crc32);
289 		return 0;
290 	}
291 
292 	/* Check that the my_lba entry points to the LBA that contains the GPT */
293 	if (le64_to_int(pgpt_head->my_lba) != lba) {
294 		printf("GPT: my_lba incorrect: %llX != %llX\n",
295 			(unsigned long long)le64_to_int(pgpt_head->my_lba),
296 			(unsigned long long)lba);
297 		return 0;
298 	}
299 
300 	/* Check the first_usable_lba and last_usable_lba are within the disk. */
301 	lastlba = (unsigned long long)dev_desc->lba;
302 	if (le64_to_int(pgpt_head->first_usable_lba) > lastlba) {
303 		printf("GPT: first_usable_lba incorrect: %llX > %llX\n",
304 			le64_to_int(pgpt_head->first_usable_lba), lastlba);
305 		return 0;
306 	}
307 	if (le64_to_int(pgpt_head->last_usable_lba) > lastlba) {
308 		printf("GPT: last_usable_lba incorrect: %llX > %llX\n",
309 			le64_to_int(pgpt_head->last_usable_lba), lastlba);
310 		return 0;
311 	}
312 
313 	debug("GPT: first_usable_lba: %llX last_usable_lba %llX last lba %llX\n",
314 		le64_to_int(pgpt_head->first_usable_lba),
315 		le64_to_int(pgpt_head->last_usable_lba), lastlba);
316 
317 	/* Read and allocate Partition Table Entries */
318 	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
319 	if (*pgpt_pte == NULL) {
320 		printf("GPT: Failed to allocate memory for PTE\n");
321 		return 0;
322 	}
323 
324 	/* Check the GUID Partition Table Entry Array CRC */
325 	calc_crc32 = efi_crc32((const unsigned char *)*pgpt_pte,
326 		le32_to_int(pgpt_head->num_partition_entries) *
327 		le32_to_int(pgpt_head->sizeof_partition_entry));
328 
329 	if (calc_crc32 != le32_to_int(pgpt_head->partition_entry_array_crc32)) {
330 		printf("GUID Partition Table Entry Array CRC is wrong:"
331 			"0x%08lX != 0x%08lX\n",
332 			le32_to_int(pgpt_head->partition_entry_array_crc32),
333 			calc_crc32);
334 
335 		if (*pgpt_pte != NULL) {
336 			free(*pgpt_pte);
337 		}
338 		return 0;
339 	}
340 
341 	/* We're done, all's well */
342 	return 1;
343 }
344 
345 /**
346  * alloc_read_gpt_entries(): reads partition entries from disk
347  * @dev_desc
348  * @gpt - GPT header
349  *
350  * Description: Returns ptes on success,  NULL on error.
351  * Allocates space for PTEs based on information found in @gpt.
352  * Notes: remember to free pte when you're done!
353  */
354 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
355 					 gpt_header * pgpt_head)
356 {
357 	size_t count = 0;
358 	gpt_entry *pte = NULL;
359 
360 	if (!dev_desc || !pgpt_head) {
361 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
362 		return NULL;
363 	}
364 
365 	count = le32_to_int(pgpt_head->num_partition_entries) *
366 		le32_to_int(pgpt_head->sizeof_partition_entry);
367 
368 	debug("%s: count = %lu * %lu = %u\n", __FUNCTION__,
369 		le32_to_int(pgpt_head->num_partition_entries),
370 		le32_to_int(pgpt_head->sizeof_partition_entry), count);
371 
372 	/* Allocate memory for PTE, remember to FREE */
373 	if (count != 0) {
374 		pte = malloc(count);
375 	}
376 
377 	if (count == 0 || pte == NULL) {
378 		printf("%s: ERROR: Can't allocate 0x%X bytes for GPT Entries\n",
379 			__FUNCTION__, count);
380 		return NULL;
381 	}
382 
383 	/* Read GPT Entries from device */
384 	if (dev_desc->block_read (dev_desc->dev,
385 		(unsigned long)le64_to_int(pgpt_head->partition_entry_lba),
386 		(lbaint_t) (count / GPT_BLOCK_SIZE), pte)
387 		!= (count / GPT_BLOCK_SIZE)) {
388 
389 		printf("*** ERROR: Can't read GPT Entries ***\n");
390 		free(pte);
391 		return NULL;
392 	}
393 	return pte;
394 }
395 
396 /**
397  * is_pte_valid(): validates a single Partition Table Entry
398  * @gpt_entry - Pointer to a single Partition Table Entry
399  *
400  * Description: returns 1 if valid,  0 on error.
401  */
402 static int is_pte_valid(gpt_entry * pte)
403 {
404 	efi_guid_t unused_guid;
405 
406 	if (!pte) {
407 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
408 		return 0;
409 	}
410 
411 	/* Only one validation for now:
412 	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
413 	 */
414 	memset(unused_guid.b, 0, sizeof(unused_guid.b));
415 
416 	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
417 		sizeof(unused_guid.b)) == 0) {
418 
419 		debug("%s: Found an unused PTE GUID at 0x%08X\n", __FUNCTION__,
420 		(unsigned int)pte);
421 
422 		return 0;
423 	} else {
424 		return 1;
425 	}
426 }
427 #endif
428