xref: /openbmc/u-boot/disk/part_efi.c (revision 3c03f492)
1 /*
2  * Copyright (C) 2008 RuggedCom, Inc.
3  * Richard Retanubun <RichardRetanubun@RuggedCom.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /*
9  * NOTE:
10  *   when CONFIG_SYS_64BIT_LBA is not defined, lbaint_t is 32 bits; this
11  *   limits the maximum size of addressable storage to < 2 Terra Bytes
12  */
13 #include <asm/unaligned.h>
14 #include <common.h>
15 #include <command.h>
16 #include <ide.h>
17 #include <inttypes.h>
18 #include <malloc.h>
19 #include <memalign.h>
20 #include <part_efi.h>
21 #include <linux/ctype.h>
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 #ifdef HAVE_BLOCK_DEVICE
26 /**
27  * efi_crc32() - EFI version of crc32 function
28  * @buf: buffer to calculate crc32 of
29  * @len - length of buf
30  *
31  * Description: Returns EFI-style CRC32 value for @buf
32  */
33 static inline u32 efi_crc32(const void *buf, u32 len)
34 {
35 	return crc32(0, buf, len);
36 }
37 
38 /*
39  * Private function prototypes
40  */
41 
42 static int pmbr_part_valid(struct partition *part);
43 static int is_pmbr_valid(legacy_mbr * mbr);
44 static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba,
45 				gpt_header *pgpt_head, gpt_entry **pgpt_pte);
46 static gpt_entry *alloc_read_gpt_entries(struct blk_desc *dev_desc,
47 					 gpt_header *pgpt_head);
48 static int is_pte_valid(gpt_entry * pte);
49 
50 static char *print_efiname(gpt_entry *pte)
51 {
52 	static char name[PARTNAME_SZ + 1];
53 	int i;
54 	for (i = 0; i < PARTNAME_SZ; i++) {
55 		u8 c;
56 		c = pte->partition_name[i] & 0xff;
57 		c = (c && !isprint(c)) ? '.' : c;
58 		name[i] = c;
59 	}
60 	name[PARTNAME_SZ] = 0;
61 	return name;
62 }
63 
64 static efi_guid_t system_guid = PARTITION_SYSTEM_GUID;
65 
66 static inline int is_bootable(gpt_entry *p)
67 {
68 	return p->attributes.fields.legacy_bios_bootable ||
69 		!memcmp(&(p->partition_type_guid), &system_guid,
70 			sizeof(efi_guid_t));
71 }
72 
73 static int validate_gpt_header(gpt_header *gpt_h, lbaint_t lba,
74 		lbaint_t lastlba)
75 {
76 	uint32_t crc32_backup = 0;
77 	uint32_t calc_crc32;
78 
79 	/* Check the GPT header signature */
80 	if (le64_to_cpu(gpt_h->signature) != GPT_HEADER_SIGNATURE) {
81 		printf("%s signature is wrong: 0x%llX != 0x%llX\n",
82 		       "GUID Partition Table Header",
83 		       le64_to_cpu(gpt_h->signature),
84 		       GPT_HEADER_SIGNATURE);
85 		return -1;
86 	}
87 
88 	/* Check the GUID Partition Table CRC */
89 	memcpy(&crc32_backup, &gpt_h->header_crc32, sizeof(crc32_backup));
90 	memset(&gpt_h->header_crc32, 0, sizeof(gpt_h->header_crc32));
91 
92 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
93 		le32_to_cpu(gpt_h->header_size));
94 
95 	memcpy(&gpt_h->header_crc32, &crc32_backup, sizeof(crc32_backup));
96 
97 	if (calc_crc32 != le32_to_cpu(crc32_backup)) {
98 		printf("%s CRC is wrong: 0x%x != 0x%x\n",
99 		       "GUID Partition Table Header",
100 		       le32_to_cpu(crc32_backup), calc_crc32);
101 		return -1;
102 	}
103 
104 	/*
105 	 * Check that the my_lba entry points to the LBA that contains the GPT
106 	 */
107 	if (le64_to_cpu(gpt_h->my_lba) != lba) {
108 		printf("GPT: my_lba incorrect: %llX != " LBAF "\n",
109 		       le64_to_cpu(gpt_h->my_lba),
110 		       lba);
111 		return -1;
112 	}
113 
114 	/*
115 	 * Check that the first_usable_lba and that the last_usable_lba are
116 	 * within the disk.
117 	 */
118 	if (le64_to_cpu(gpt_h->first_usable_lba) > lastlba) {
119 		printf("GPT: first_usable_lba incorrect: %llX > " LBAF "\n",
120 		       le64_to_cpu(gpt_h->first_usable_lba), lastlba);
121 		return -1;
122 	}
123 	if (le64_to_cpu(gpt_h->last_usable_lba) > lastlba) {
124 		printf("GPT: last_usable_lba incorrect: %llX > " LBAF "\n",
125 		       le64_to_cpu(gpt_h->last_usable_lba), lastlba);
126 		return -1;
127 	}
128 
129 	debug("GPT: first_usable_lba: %llX last_usable_lba: %llX last lba: "
130 	      LBAF "\n", le64_to_cpu(gpt_h->first_usable_lba),
131 	      le64_to_cpu(gpt_h->last_usable_lba), lastlba);
132 
133 	return 0;
134 }
135 
136 static int validate_gpt_entries(gpt_header *gpt_h, gpt_entry *gpt_e)
137 {
138 	uint32_t calc_crc32;
139 
140 	/* Check the GUID Partition Table Entry Array CRC */
141 	calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
142 		le32_to_cpu(gpt_h->num_partition_entries) *
143 		le32_to_cpu(gpt_h->sizeof_partition_entry));
144 
145 	if (calc_crc32 != le32_to_cpu(gpt_h->partition_entry_array_crc32)) {
146 		printf("%s: 0x%x != 0x%x\n",
147 		       "GUID Partition Table Entry Array CRC is wrong",
148 		       le32_to_cpu(gpt_h->partition_entry_array_crc32),
149 		       calc_crc32);
150 		return -1;
151 	}
152 
153 	return 0;
154 }
155 
156 static void prepare_backup_gpt_header(gpt_header *gpt_h)
157 {
158 	uint32_t calc_crc32;
159 	uint64_t val;
160 
161 	/* recalculate the values for the Backup GPT Header */
162 	val = le64_to_cpu(gpt_h->my_lba);
163 	gpt_h->my_lba = gpt_h->alternate_lba;
164 	gpt_h->alternate_lba = cpu_to_le64(val);
165 	gpt_h->partition_entry_lba =
166 			cpu_to_le64(le64_to_cpu(gpt_h->last_usable_lba) + 1);
167 	gpt_h->header_crc32 = 0;
168 
169 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
170 			       le32_to_cpu(gpt_h->header_size));
171 	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
172 }
173 
174 #if CONFIG_IS_ENABLED(EFI_PARTITION)
175 /*
176  * Public Functions (include/part.h)
177  */
178 
179 void part_print_efi(struct blk_desc *dev_desc)
180 {
181 	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
182 	gpt_entry *gpt_pte = NULL;
183 	int i = 0;
184 	char uuid[37];
185 	unsigned char *uuid_bin;
186 
187 	/* This function validates AND fills in the GPT header and PTE */
188 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
189 			 gpt_head, &gpt_pte) != 1) {
190 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
191 		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
192 				 gpt_head, &gpt_pte) != 1) {
193 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
194 			       __func__);
195 			return;
196 		} else {
197 			printf("%s: ***        Using Backup GPT ***\n",
198 			       __func__);
199 		}
200 	}
201 
202 	debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
203 
204 	printf("Part\tStart LBA\tEnd LBA\t\tName\n");
205 	printf("\tAttributes\n");
206 	printf("\tType GUID\n");
207 	printf("\tPartition GUID\n");
208 
209 	for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) {
210 		/* Stop at the first non valid PTE */
211 		if (!is_pte_valid(&gpt_pte[i]))
212 			break;
213 
214 		printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1),
215 			le64_to_cpu(gpt_pte[i].starting_lba),
216 			le64_to_cpu(gpt_pte[i].ending_lba),
217 			print_efiname(&gpt_pte[i]));
218 		printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw);
219 		uuid_bin = (unsigned char *)gpt_pte[i].partition_type_guid.b;
220 		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
221 		printf("\ttype:\t%s\n", uuid);
222 #ifdef CONFIG_PARTITION_TYPE_GUID
223 		if (!uuid_guid_get_str(uuid_bin, uuid))
224 			printf("\ttype:\t%s\n", uuid);
225 #endif
226 		uuid_bin = (unsigned char *)gpt_pte[i].unique_partition_guid.b;
227 		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
228 		printf("\tguid:\t%s\n", uuid);
229 	}
230 
231 	/* Remember to free pte */
232 	free(gpt_pte);
233 	return;
234 }
235 
236 int part_get_info_efi(struct blk_desc *dev_desc, int part,
237 		      disk_partition_t *info)
238 {
239 	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
240 	gpt_entry *gpt_pte = NULL;
241 
242 	/* "part" argument must be at least 1 */
243 	if (part < 1) {
244 		printf("%s: Invalid Argument(s)\n", __func__);
245 		return -1;
246 	}
247 
248 	/* This function validates AND fills in the GPT header and PTE */
249 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
250 			gpt_head, &gpt_pte) != 1) {
251 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
252 		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
253 				 gpt_head, &gpt_pte) != 1) {
254 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
255 			       __func__);
256 			return -1;
257 		} else {
258 			printf("%s: ***        Using Backup GPT ***\n",
259 			       __func__);
260 		}
261 	}
262 
263 	if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
264 	    !is_pte_valid(&gpt_pte[part - 1])) {
265 		debug("%s: *** ERROR: Invalid partition number %d ***\n",
266 			__func__, part);
267 		free(gpt_pte);
268 		return -1;
269 	}
270 
271 	/* The 'lbaint_t' casting may limit the maximum disk size to 2 TB */
272 	info->start = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].starting_lba);
273 	/* The ending LBA is inclusive, to calculate size, add 1 to it */
274 	info->size = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1
275 		     - info->start;
276 	info->blksz = dev_desc->blksz;
277 
278 	sprintf((char *)info->name, "%s",
279 			print_efiname(&gpt_pte[part - 1]));
280 	strcpy((char *)info->type, "U-Boot");
281 	info->bootable = is_bootable(&gpt_pte[part - 1]);
282 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
283 	uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid,
284 			UUID_STR_FORMAT_GUID);
285 #endif
286 #ifdef CONFIG_PARTITION_TYPE_GUID
287 	uuid_bin_to_str(gpt_pte[part - 1].partition_type_guid.b,
288 			info->type_guid, UUID_STR_FORMAT_GUID);
289 #endif
290 
291 	debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s\n", __func__,
292 	      info->start, info->size, info->name);
293 
294 	/* Remember to free pte */
295 	free(gpt_pte);
296 	return 0;
297 }
298 
299 static int part_test_efi(struct blk_desc *dev_desc)
300 {
301 	ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz);
302 
303 	/* Read legacy MBR from block 0 and validate it */
304 	if ((blk_dread(dev_desc, 0, 1, (ulong *)legacymbr) != 1)
305 		|| (is_pmbr_valid(legacymbr) != 1)) {
306 		return -1;
307 	}
308 	return 0;
309 }
310 
311 /**
312  * set_protective_mbr(): Set the EFI protective MBR
313  * @param dev_desc - block device descriptor
314  *
315  * @return - zero on success, otherwise error
316  */
317 static int set_protective_mbr(struct blk_desc *dev_desc)
318 {
319 	/* Setup the Protective MBR */
320 	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1);
321 	memset(p_mbr, 0, sizeof(*p_mbr));
322 
323 	if (p_mbr == NULL) {
324 		printf("%s: calloc failed!\n", __func__);
325 		return -1;
326 	}
327 
328 	/* Read MBR to backup boot code if it exists */
329 	if (blk_dread(dev_desc, 0, 1, p_mbr) != 1) {
330 		error("** Can't read from device %d **\n", dev_desc->devnum);
331 		return -1;
332 	}
333 
334 	/* Append signature */
335 	p_mbr->signature = MSDOS_MBR_SIGNATURE;
336 	p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
337 	p_mbr->partition_record[0].start_sect = 1;
338 	p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba - 1;
339 
340 	/* Write MBR sector to the MMC device */
341 	if (blk_dwrite(dev_desc, 0, 1, p_mbr) != 1) {
342 		printf("** Can't write to device %d **\n",
343 			dev_desc->devnum);
344 		return -1;
345 	}
346 
347 	return 0;
348 }
349 
350 int write_gpt_table(struct blk_desc *dev_desc,
351 		gpt_header *gpt_h, gpt_entry *gpt_e)
352 {
353 	const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
354 					   * sizeof(gpt_entry)), dev_desc);
355 	u32 calc_crc32;
356 
357 	debug("max lba: %x\n", (u32) dev_desc->lba);
358 	/* Setup the Protective MBR */
359 	if (set_protective_mbr(dev_desc) < 0)
360 		goto err;
361 
362 	/* Generate CRC for the Primary GPT Header */
363 	calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
364 			      le32_to_cpu(gpt_h->num_partition_entries) *
365 			      le32_to_cpu(gpt_h->sizeof_partition_entry));
366 	gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
367 
368 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
369 			      le32_to_cpu(gpt_h->header_size));
370 	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
371 
372 	/* Write the First GPT to the block right after the Legacy MBR */
373 	if (blk_dwrite(dev_desc, 1, 1, gpt_h) != 1)
374 		goto err;
375 
376 	if (blk_dwrite(dev_desc, 2, pte_blk_cnt, gpt_e)
377 	    != pte_blk_cnt)
378 		goto err;
379 
380 	prepare_backup_gpt_header(gpt_h);
381 
382 	if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->last_usable_lba)
383 		       + 1, pte_blk_cnt, gpt_e) != pte_blk_cnt)
384 		goto err;
385 
386 	if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->my_lba), 1,
387 		       gpt_h) != 1)
388 		goto err;
389 
390 	debug("GPT successfully written to block device!\n");
391 	return 0;
392 
393  err:
394 	printf("** Can't write to device %d **\n", dev_desc->devnum);
395 	return -1;
396 }
397 
398 int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e,
399 		disk_partition_t *partitions, int parts)
400 {
401 	lbaint_t offset = (lbaint_t)le64_to_cpu(gpt_h->first_usable_lba);
402 	lbaint_t start;
403 	lbaint_t last_usable_lba = (lbaint_t)
404 			le64_to_cpu(gpt_h->last_usable_lba);
405 	int i, k;
406 	size_t efiname_len, dosname_len;
407 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
408 	char *str_uuid;
409 	unsigned char *bin_uuid;
410 #endif
411 #ifdef CONFIG_PARTITION_TYPE_GUID
412 	char *str_type_guid;
413 	unsigned char *bin_type_guid;
414 #endif
415 
416 	for (i = 0; i < parts; i++) {
417 		/* partition starting lba */
418 		start = partitions[i].start;
419 		if (start && (start < offset)) {
420 			printf("Partition overlap\n");
421 			return -1;
422 		}
423 		if (start) {
424 			gpt_e[i].starting_lba = cpu_to_le64(start);
425 			offset = start + partitions[i].size;
426 		} else {
427 			gpt_e[i].starting_lba = cpu_to_le64(offset);
428 			offset += partitions[i].size;
429 		}
430 		if (offset > (last_usable_lba + 1)) {
431 			printf("Partitions layout exceds disk size\n");
432 			return -1;
433 		}
434 		/* partition ending lba */
435 		if ((i == parts - 1) && (partitions[i].size == 0))
436 			/* extend the last partition to maximuim */
437 			gpt_e[i].ending_lba = gpt_h->last_usable_lba;
438 		else
439 			gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
440 
441 #ifdef CONFIG_PARTITION_TYPE_GUID
442 		str_type_guid = partitions[i].type_guid;
443 		bin_type_guid = gpt_e[i].partition_type_guid.b;
444 		if (strlen(str_type_guid)) {
445 			if (uuid_str_to_bin(str_type_guid, bin_type_guid,
446 					    UUID_STR_FORMAT_GUID)) {
447 				printf("Partition no. %d: invalid type guid: %s\n",
448 				       i, str_type_guid);
449 				return -1;
450 			}
451 		} else {
452 			/* default partition type GUID */
453 			memcpy(bin_type_guid,
454 			       &PARTITION_BASIC_DATA_GUID, 16);
455 		}
456 #else
457 		/* partition type GUID */
458 		memcpy(gpt_e[i].partition_type_guid.b,
459 			&PARTITION_BASIC_DATA_GUID, 16);
460 #endif
461 
462 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
463 		str_uuid = partitions[i].uuid;
464 		bin_uuid = gpt_e[i].unique_partition_guid.b;
465 
466 		if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_STD)) {
467 			printf("Partition no. %d: invalid guid: %s\n",
468 				i, str_uuid);
469 			return -1;
470 		}
471 #endif
472 
473 		/* partition attributes */
474 		memset(&gpt_e[i].attributes, 0,
475 		       sizeof(gpt_entry_attributes));
476 
477 		if (partitions[i].bootable)
478 			gpt_e[i].attributes.fields.legacy_bios_bootable = 1;
479 
480 		/* partition name */
481 		efiname_len = sizeof(gpt_e[i].partition_name)
482 			/ sizeof(efi_char16_t);
483 		dosname_len = sizeof(partitions[i].name);
484 
485 		memset(gpt_e[i].partition_name, 0,
486 		       sizeof(gpt_e[i].partition_name));
487 
488 		for (k = 0; k < min(dosname_len, efiname_len); k++)
489 			gpt_e[i].partition_name[k] =
490 				(efi_char16_t)(partitions[i].name[k]);
491 
492 		debug("%s: name: %s offset[%d]: 0x" LBAF
493 		      " size[%d]: 0x" LBAF "\n",
494 		      __func__, partitions[i].name, i,
495 		      offset, i, partitions[i].size);
496 	}
497 
498 	return 0;
499 }
500 
501 int gpt_fill_header(struct blk_desc *dev_desc, gpt_header *gpt_h,
502 		char *str_guid, int parts_count)
503 {
504 	gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
505 	gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
506 	gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
507 	gpt_h->my_lba = cpu_to_le64(1);
508 	gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
509 	gpt_h->first_usable_lba = cpu_to_le64(34);
510 	gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
511 	gpt_h->partition_entry_lba = cpu_to_le64(2);
512 	gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
513 	gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
514 	gpt_h->header_crc32 = 0;
515 	gpt_h->partition_entry_array_crc32 = 0;
516 
517 	if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
518 		return -1;
519 
520 	return 0;
521 }
522 
523 int gpt_restore(struct blk_desc *dev_desc, char *str_disk_guid,
524 		disk_partition_t *partitions, int parts_count)
525 {
526 	int ret;
527 
528 	gpt_header *gpt_h = calloc(1, PAD_TO_BLOCKSIZE(sizeof(gpt_header),
529 						       dev_desc));
530 	gpt_entry *gpt_e;
531 
532 	if (gpt_h == NULL) {
533 		printf("%s: calloc failed!\n", __func__);
534 		return -1;
535 	}
536 
537 	gpt_e = calloc(1, PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS
538 					       * sizeof(gpt_entry),
539 					       dev_desc));
540 	if (gpt_e == NULL) {
541 		printf("%s: calloc failed!\n", __func__);
542 		free(gpt_h);
543 		return -1;
544 	}
545 
546 	/* Generate Primary GPT header (LBA1) */
547 	ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
548 	if (ret)
549 		goto err;
550 
551 	/* Generate partition entries */
552 	ret = gpt_fill_pte(gpt_h, gpt_e, partitions, parts_count);
553 	if (ret)
554 		goto err;
555 
556 	/* Write GPT partition table */
557 	ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
558 
559 err:
560 	free(gpt_e);
561 	free(gpt_h);
562 	return ret;
563 }
564 
565 static void gpt_convert_efi_name_to_char(char *s, efi_char16_t *es, int n)
566 {
567 	char *ess = (char *)es;
568 	int i, j;
569 
570 	memset(s, '\0', n);
571 
572 	for (i = 0, j = 0; j < n; i += 2, j++) {
573 		s[j] = ess[i];
574 		if (!ess[i])
575 			return;
576 	}
577 }
578 
579 int gpt_verify_headers(struct blk_desc *dev_desc, gpt_header *gpt_head,
580 		       gpt_entry **gpt_pte)
581 {
582 	/*
583 	 * This function validates AND
584 	 * fills in the GPT header and PTE
585 	 */
586 	if (is_gpt_valid(dev_desc,
587 			 GPT_PRIMARY_PARTITION_TABLE_LBA,
588 			 gpt_head, gpt_pte) != 1) {
589 		printf("%s: *** ERROR: Invalid GPT ***\n",
590 		       __func__);
591 		return -1;
592 	}
593 	if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
594 			 gpt_head, gpt_pte) != 1) {
595 		printf("%s: *** ERROR: Invalid Backup GPT ***\n",
596 		       __func__);
597 		return -1;
598 	}
599 
600 	return 0;
601 }
602 
603 int gpt_verify_partitions(struct blk_desc *dev_desc,
604 			  disk_partition_t *partitions, int parts,
605 			  gpt_header *gpt_head, gpt_entry **gpt_pte)
606 {
607 	char efi_str[PARTNAME_SZ + 1];
608 	u64 gpt_part_size;
609 	gpt_entry *gpt_e;
610 	int ret, i;
611 
612 	ret = gpt_verify_headers(dev_desc, gpt_head, gpt_pte);
613 	if (ret)
614 		return ret;
615 
616 	gpt_e = *gpt_pte;
617 
618 	for (i = 0; i < parts; i++) {
619 		if (i == gpt_head->num_partition_entries) {
620 			error("More partitions than allowed!\n");
621 			return -1;
622 		}
623 
624 		/* Check if GPT and ENV partition names match */
625 		gpt_convert_efi_name_to_char(efi_str, gpt_e[i].partition_name,
626 					     PARTNAME_SZ + 1);
627 
628 		debug("%s: part: %2d name - GPT: %16s, ENV: %16s ",
629 		      __func__, i, efi_str, partitions[i].name);
630 
631 		if (strncmp(efi_str, (char *)partitions[i].name,
632 			    sizeof(partitions->name))) {
633 			error("Partition name: %s does not match %s!\n",
634 			      efi_str, (char *)partitions[i].name);
635 			return -1;
636 		}
637 
638 		/* Check if GPT and ENV sizes match */
639 		gpt_part_size = le64_to_cpu(gpt_e[i].ending_lba) -
640 			le64_to_cpu(gpt_e[i].starting_lba) + 1;
641 		debug("size(LBA) - GPT: %8llu, ENV: %8llu ",
642 		      (unsigned long long)gpt_part_size,
643 		      (unsigned long long)partitions[i].size);
644 
645 		if (le64_to_cpu(gpt_part_size) != partitions[i].size) {
646 			/* We do not check the extend partition size */
647 			if ((i == parts - 1) && (partitions[i].size == 0))
648 				continue;
649 
650 			error("Partition %s size: %llu does not match %llu!\n",
651 			      efi_str, (unsigned long long)gpt_part_size,
652 			      (unsigned long long)partitions[i].size);
653 			return -1;
654 		}
655 
656 		/*
657 		 * Start address is optional - check only if provided
658 		 * in '$partition' variable
659 		 */
660 		if (!partitions[i].start) {
661 			debug("\n");
662 			continue;
663 		}
664 
665 		/* Check if GPT and ENV start LBAs match */
666 		debug("start LBA - GPT: %8llu, ENV: %8llu\n",
667 		      le64_to_cpu(gpt_e[i].starting_lba),
668 		      (unsigned long long)partitions[i].start);
669 
670 		if (le64_to_cpu(gpt_e[i].starting_lba) != partitions[i].start) {
671 			error("Partition %s start: %llu does not match %llu!\n",
672 			      efi_str, le64_to_cpu(gpt_e[i].starting_lba),
673 			      (unsigned long long)partitions[i].start);
674 			return -1;
675 		}
676 	}
677 
678 	return 0;
679 }
680 
681 int is_valid_gpt_buf(struct blk_desc *dev_desc, void *buf)
682 {
683 	gpt_header *gpt_h;
684 	gpt_entry *gpt_e;
685 
686 	/* determine start of GPT Header in the buffer */
687 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
688 		       dev_desc->blksz);
689 	if (validate_gpt_header(gpt_h, GPT_PRIMARY_PARTITION_TABLE_LBA,
690 				dev_desc->lba))
691 		return -1;
692 
693 	/* determine start of GPT Entries in the buffer */
694 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
695 		       dev_desc->blksz);
696 	if (validate_gpt_entries(gpt_h, gpt_e))
697 		return -1;
698 
699 	return 0;
700 }
701 
702 int write_mbr_and_gpt_partitions(struct blk_desc *dev_desc, void *buf)
703 {
704 	gpt_header *gpt_h;
705 	gpt_entry *gpt_e;
706 	int gpt_e_blk_cnt;
707 	lbaint_t lba;
708 	int cnt;
709 
710 	if (is_valid_gpt_buf(dev_desc, buf))
711 		return -1;
712 
713 	/* determine start of GPT Header in the buffer */
714 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
715 		       dev_desc->blksz);
716 
717 	/* determine start of GPT Entries in the buffer */
718 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
719 		       dev_desc->blksz);
720 	gpt_e_blk_cnt = BLOCK_CNT((le32_to_cpu(gpt_h->num_partition_entries) *
721 				   le32_to_cpu(gpt_h->sizeof_partition_entry)),
722 				  dev_desc);
723 
724 	/* write MBR */
725 	lba = 0;	/* MBR is always at 0 */
726 	cnt = 1;	/* MBR (1 block) */
727 	if (blk_dwrite(dev_desc, lba, cnt, buf) != cnt) {
728 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
729 		       __func__, "MBR", cnt, lba);
730 		return 1;
731 	}
732 
733 	/* write Primary GPT */
734 	lba = GPT_PRIMARY_PARTITION_TABLE_LBA;
735 	cnt = 1;	/* GPT Header (1 block) */
736 	if (blk_dwrite(dev_desc, lba, cnt, gpt_h) != cnt) {
737 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
738 		       __func__, "Primary GPT Header", cnt, lba);
739 		return 1;
740 	}
741 
742 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
743 	cnt = gpt_e_blk_cnt;
744 	if (blk_dwrite(dev_desc, lba, cnt, gpt_e) != cnt) {
745 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
746 		       __func__, "Primary GPT Entries", cnt, lba);
747 		return 1;
748 	}
749 
750 	prepare_backup_gpt_header(gpt_h);
751 
752 	/* write Backup GPT */
753 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
754 	cnt = gpt_e_blk_cnt;
755 	if (blk_dwrite(dev_desc, lba, cnt, gpt_e) != cnt) {
756 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
757 		       __func__, "Backup GPT Entries", cnt, lba);
758 		return 1;
759 	}
760 
761 	lba = le64_to_cpu(gpt_h->my_lba);
762 	cnt = 1;	/* GPT Header (1 block) */
763 	if (blk_dwrite(dev_desc, lba, cnt, gpt_h) != cnt) {
764 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
765 		       __func__, "Backup GPT Header", cnt, lba);
766 		return 1;
767 	}
768 
769 	return 0;
770 }
771 #endif
772 
773 /*
774  * Private functions
775  */
776 /*
777  * pmbr_part_valid(): Check for EFI partition signature
778  *
779  * Returns: 1 if EFI GPT partition type is found.
780  */
781 static int pmbr_part_valid(struct partition *part)
782 {
783 	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
784 		get_unaligned_le32(&part->start_sect) == 1UL) {
785 		return 1;
786 	}
787 
788 	return 0;
789 }
790 
791 /*
792  * is_pmbr_valid(): test Protective MBR for validity
793  *
794  * Returns: 1 if PMBR is valid, 0 otherwise.
795  * Validity depends on two things:
796  *  1) MSDOS signature is in the last two bytes of the MBR
797  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
798  */
799 static int is_pmbr_valid(legacy_mbr * mbr)
800 {
801 	int i = 0;
802 
803 	if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
804 		return 0;
805 
806 	for (i = 0; i < 4; i++) {
807 		if (pmbr_part_valid(&mbr->partition_record[i])) {
808 			return 1;
809 		}
810 	}
811 	return 0;
812 }
813 
814 /**
815  * is_gpt_valid() - tests one GPT header and PTEs for validity
816  *
817  * lba is the logical block address of the GPT header to test
818  * gpt is a GPT header ptr, filled on return.
819  * ptes is a PTEs ptr, filled on return.
820  *
821  * Description: returns 1 if valid,  0 on error.
822  * If valid, returns pointers to PTEs.
823  */
824 static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba,
825 			gpt_header *pgpt_head, gpt_entry **pgpt_pte)
826 {
827 	if (!dev_desc || !pgpt_head) {
828 		printf("%s: Invalid Argument(s)\n", __func__);
829 		return 0;
830 	}
831 
832 	/* Read GPT Header from device */
833 	if (blk_dread(dev_desc, (lbaint_t)lba, 1, pgpt_head) != 1) {
834 		printf("*** ERROR: Can't read GPT header ***\n");
835 		return 0;
836 	}
837 
838 	if (validate_gpt_header(pgpt_head, (lbaint_t)lba, dev_desc->lba))
839 		return 0;
840 
841 	/* Read and allocate Partition Table Entries */
842 	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
843 	if (*pgpt_pte == NULL) {
844 		printf("GPT: Failed to allocate memory for PTE\n");
845 		return 0;
846 	}
847 
848 	if (validate_gpt_entries(pgpt_head, *pgpt_pte)) {
849 		free(*pgpt_pte);
850 		return 0;
851 	}
852 
853 	/* We're done, all's well */
854 	return 1;
855 }
856 
857 /**
858  * alloc_read_gpt_entries(): reads partition entries from disk
859  * @dev_desc
860  * @gpt - GPT header
861  *
862  * Description: Returns ptes on success,  NULL on error.
863  * Allocates space for PTEs based on information found in @gpt.
864  * Notes: remember to free pte when you're done!
865  */
866 static gpt_entry *alloc_read_gpt_entries(struct blk_desc *dev_desc,
867 					 gpt_header *pgpt_head)
868 {
869 	size_t count = 0, blk_cnt;
870 	lbaint_t blk;
871 	gpt_entry *pte = NULL;
872 
873 	if (!dev_desc || !pgpt_head) {
874 		printf("%s: Invalid Argument(s)\n", __func__);
875 		return NULL;
876 	}
877 
878 	count = le32_to_cpu(pgpt_head->num_partition_entries) *
879 		le32_to_cpu(pgpt_head->sizeof_partition_entry);
880 
881 	debug("%s: count = %u * %u = %lu\n", __func__,
882 	      (u32) le32_to_cpu(pgpt_head->num_partition_entries),
883 	      (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry),
884 	      (ulong)count);
885 
886 	/* Allocate memory for PTE, remember to FREE */
887 	if (count != 0) {
888 		pte = memalign(ARCH_DMA_MINALIGN,
889 			       PAD_TO_BLOCKSIZE(count, dev_desc));
890 	}
891 
892 	if (count == 0 || pte == NULL) {
893 		printf("%s: ERROR: Can't allocate %#lX bytes for GPT Entries\n",
894 		       __func__, (ulong)count);
895 		return NULL;
896 	}
897 
898 	/* Read GPT Entries from device */
899 	blk = le64_to_cpu(pgpt_head->partition_entry_lba);
900 	blk_cnt = BLOCK_CNT(count, dev_desc);
901 	if (blk_dread(dev_desc, blk, (lbaint_t)blk_cnt, pte) != blk_cnt) {
902 		printf("*** ERROR: Can't read GPT Entries ***\n");
903 		free(pte);
904 		return NULL;
905 	}
906 	return pte;
907 }
908 
909 /**
910  * is_pte_valid(): validates a single Partition Table Entry
911  * @gpt_entry - Pointer to a single Partition Table Entry
912  *
913  * Description: returns 1 if valid,  0 on error.
914  */
915 static int is_pte_valid(gpt_entry * pte)
916 {
917 	efi_guid_t unused_guid;
918 
919 	if (!pte) {
920 		printf("%s: Invalid Argument(s)\n", __func__);
921 		return 0;
922 	}
923 
924 	/* Only one validation for now:
925 	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
926 	 */
927 	memset(unused_guid.b, 0, sizeof(unused_guid.b));
928 
929 	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
930 		sizeof(unused_guid.b)) == 0) {
931 
932 		debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
933 		      (unsigned int)(uintptr_t)pte);
934 
935 		return 0;
936 	} else {
937 		return 1;
938 	}
939 }
940 
941 /*
942  * Add an 'a_' prefix so it comes before 'dos' in the linker list. We need to
943  * check EFI first, since a DOS partition is often used as a 'protective MBR'
944  * with EFI.
945  */
946 U_BOOT_PART_TYPE(a_efi) = {
947 	.name		= "EFI",
948 	.part_type	= PART_TYPE_EFI,
949 	.max_entries	= GPT_ENTRY_NUMBERS,
950 	.get_info	= part_get_info_ptr(part_get_info_efi),
951 	.print		= part_print_ptr(part_print_efi),
952 	.test		= part_test_efi,
953 };
954 #endif
955