xref: /openbmc/u-boot/disk/part_efi.c (revision 44da3a17)
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(block_dev_desc_t *dev_desc, u64 lba,
45 				gpt_header *pgpt_head, gpt_entry **pgpt_pte);
46 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * 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 #ifdef CONFIG_EFI_PARTITION
175 /*
176  * Public Functions (include/part.h)
177  */
178 
179 void print_part_efi(block_dev_desc_t * 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 	if (!dev_desc) {
188 		printf("%s: Invalid Argument(s)\n", __func__);
189 		return;
190 	}
191 	/* This function validates AND fills in the GPT header and PTE */
192 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
193 			 gpt_head, &gpt_pte) != 1) {
194 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
195 		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
196 				 gpt_head, &gpt_pte) != 1) {
197 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
198 			       __func__);
199 			return;
200 		} else {
201 			printf("%s: ***        Using Backup GPT ***\n",
202 			       __func__);
203 		}
204 	}
205 
206 	debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
207 
208 	printf("Part\tStart LBA\tEnd LBA\t\tName\n");
209 	printf("\tAttributes\n");
210 	printf("\tType GUID\n");
211 	printf("\tPartition GUID\n");
212 
213 	for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) {
214 		/* Stop at the first non valid PTE */
215 		if (!is_pte_valid(&gpt_pte[i]))
216 			break;
217 
218 		printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1),
219 			le64_to_cpu(gpt_pte[i].starting_lba),
220 			le64_to_cpu(gpt_pte[i].ending_lba),
221 			print_efiname(&gpt_pte[i]));
222 		printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw);
223 		uuid_bin = (unsigned char *)gpt_pte[i].partition_type_guid.b;
224 		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
225 		printf("\ttype:\t%s\n", uuid);
226 #ifdef CONFIG_PARTITION_TYPE_GUID
227 		if (!uuid_guid_get_str(uuid_bin, uuid))
228 			printf("\ttype:\t%s\n", uuid);
229 #endif
230 		uuid_bin = (unsigned char *)gpt_pte[i].unique_partition_guid.b;
231 		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
232 		printf("\tguid:\t%s\n", uuid);
233 	}
234 
235 	/* Remember to free pte */
236 	free(gpt_pte);
237 	return;
238 }
239 
240 int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
241 				disk_partition_t * info)
242 {
243 	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
244 	gpt_entry *gpt_pte = NULL;
245 
246 	/* "part" argument must be at least 1 */
247 	if (!dev_desc || !info || part < 1) {
248 		printf("%s: Invalid Argument(s)\n", __func__);
249 		return -1;
250 	}
251 
252 	/* This function validates AND fills in the GPT header and PTE */
253 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
254 			gpt_head, &gpt_pte) != 1) {
255 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
256 		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
257 				 gpt_head, &gpt_pte) != 1) {
258 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
259 			       __func__);
260 			return -1;
261 		} else {
262 			printf("%s: ***        Using Backup GPT ***\n",
263 			       __func__);
264 		}
265 	}
266 
267 	if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
268 	    !is_pte_valid(&gpt_pte[part - 1])) {
269 		debug("%s: *** ERROR: Invalid partition number %d ***\n",
270 			__func__, part);
271 		free(gpt_pte);
272 		return -1;
273 	}
274 
275 	/* The 'lbaint_t' casting may limit the maximum disk size to 2 TB */
276 	info->start = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].starting_lba);
277 	/* The ending LBA is inclusive, to calculate size, add 1 to it */
278 	info->size = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1
279 		     - info->start;
280 	info->blksz = dev_desc->blksz;
281 
282 	sprintf((char *)info->name, "%s",
283 			print_efiname(&gpt_pte[part - 1]));
284 	strcpy((char *)info->type, "U-Boot");
285 	info->bootable = is_bootable(&gpt_pte[part - 1]);
286 #ifdef CONFIG_PARTITION_UUIDS
287 	uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid,
288 			UUID_STR_FORMAT_GUID);
289 #endif
290 #ifdef CONFIG_PARTITION_TYPE_GUID
291 	uuid_bin_to_str(gpt_pte[part - 1].partition_type_guid.b,
292 			info->type_guid, UUID_STR_FORMAT_GUID);
293 #endif
294 
295 	debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s\n", __func__,
296 	      info->start, info->size, info->name);
297 
298 	/* Remember to free pte */
299 	free(gpt_pte);
300 	return 0;
301 }
302 
303 int get_partition_info_efi_by_name(block_dev_desc_t *dev_desc,
304 	const char *name, disk_partition_t *info)
305 {
306 	int ret;
307 	int i;
308 	for (i = 1; i < GPT_ENTRY_NUMBERS; i++) {
309 		ret = get_partition_info_efi(dev_desc, i, info);
310 		if (ret != 0) {
311 			/* no more entries in table */
312 			return -1;
313 		}
314 		if (strcmp(name, (const char *)info->name) == 0) {
315 			/* matched */
316 			return 0;
317 		}
318 	}
319 	return -2;
320 }
321 
322 int test_part_efi(block_dev_desc_t * dev_desc)
323 {
324 	ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz);
325 
326 	/* Read legacy MBR from block 0 and validate it */
327 	if ((dev_desc->block_read(dev_desc, 0, 1, (ulong *)legacymbr) != 1)
328 		|| (is_pmbr_valid(legacymbr) != 1)) {
329 		return -1;
330 	}
331 	return 0;
332 }
333 
334 /**
335  * set_protective_mbr(): Set the EFI protective MBR
336  * @param dev_desc - block device descriptor
337  *
338  * @return - zero on success, otherwise error
339  */
340 static int set_protective_mbr(block_dev_desc_t *dev_desc)
341 {
342 	/* Setup the Protective MBR */
343 	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1);
344 	memset(p_mbr, 0, sizeof(*p_mbr));
345 
346 	if (p_mbr == NULL) {
347 		printf("%s: calloc failed!\n", __func__);
348 		return -1;
349 	}
350 	/* Append signature */
351 	p_mbr->signature = MSDOS_MBR_SIGNATURE;
352 	p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
353 	p_mbr->partition_record[0].start_sect = 1;
354 	p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba - 1;
355 
356 	/* Write MBR sector to the MMC device */
357 	if (dev_desc->block_write(dev_desc, 0, 1, p_mbr) != 1) {
358 		printf("** Can't write to device %d **\n",
359 			dev_desc->dev);
360 		return -1;
361 	}
362 
363 	return 0;
364 }
365 
366 int write_gpt_table(block_dev_desc_t *dev_desc,
367 		gpt_header *gpt_h, gpt_entry *gpt_e)
368 {
369 	const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
370 					   * sizeof(gpt_entry)), dev_desc);
371 	u32 calc_crc32;
372 
373 	debug("max lba: %x\n", (u32) dev_desc->lba);
374 	/* Setup the Protective MBR */
375 	if (set_protective_mbr(dev_desc) < 0)
376 		goto err;
377 
378 	/* Generate CRC for the Primary GPT Header */
379 	calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
380 			      le32_to_cpu(gpt_h->num_partition_entries) *
381 			      le32_to_cpu(gpt_h->sizeof_partition_entry));
382 	gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
383 
384 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
385 			      le32_to_cpu(gpt_h->header_size));
386 	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
387 
388 	/* Write the First GPT to the block right after the Legacy MBR */
389 	if (dev_desc->block_write(dev_desc, 1, 1, gpt_h) != 1)
390 		goto err;
391 
392 	if (dev_desc->block_write(dev_desc, 2, pte_blk_cnt, gpt_e)
393 	    != pte_blk_cnt)
394 		goto err;
395 
396 	prepare_backup_gpt_header(gpt_h);
397 
398 	if (dev_desc->block_write(dev_desc,
399 				  (lbaint_t)le64_to_cpu(gpt_h->last_usable_lba)
400 				  + 1,
401 				  pte_blk_cnt, gpt_e) != pte_blk_cnt)
402 		goto err;
403 
404 	if (dev_desc->block_write(dev_desc,
405 				  (lbaint_t)le64_to_cpu(gpt_h->my_lba), 1,
406 				  gpt_h) != 1)
407 		goto err;
408 
409 	debug("GPT successfully written to block device!\n");
410 	return 0;
411 
412  err:
413 	printf("** Can't write to device %d **\n", dev_desc->dev);
414 	return -1;
415 }
416 
417 int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e,
418 		disk_partition_t *partitions, int parts)
419 {
420 	lbaint_t offset = (lbaint_t)le64_to_cpu(gpt_h->first_usable_lba);
421 	lbaint_t start;
422 	lbaint_t last_usable_lba = (lbaint_t)
423 			le64_to_cpu(gpt_h->last_usable_lba);
424 	int i, k;
425 	size_t efiname_len, dosname_len;
426 #ifdef CONFIG_PARTITION_UUIDS
427 	char *str_uuid;
428 	unsigned char *bin_uuid;
429 #endif
430 #ifdef CONFIG_PARTITION_TYPE_GUID
431 	char *str_type_guid;
432 	unsigned char *bin_type_guid;
433 #endif
434 
435 	for (i = 0; i < parts; i++) {
436 		/* partition starting lba */
437 		start = partitions[i].start;
438 		if (start && (start < offset)) {
439 			printf("Partition overlap\n");
440 			return -1;
441 		}
442 		if (start) {
443 			gpt_e[i].starting_lba = cpu_to_le64(start);
444 			offset = start + partitions[i].size;
445 		} else {
446 			gpt_e[i].starting_lba = cpu_to_le64(offset);
447 			offset += partitions[i].size;
448 		}
449 		if (offset >= last_usable_lba) {
450 			printf("Partitions layout exceds disk size\n");
451 			return -1;
452 		}
453 		/* partition ending lba */
454 		if ((i == parts - 1) && (partitions[i].size == 0))
455 			/* extend the last partition to maximuim */
456 			gpt_e[i].ending_lba = gpt_h->last_usable_lba;
457 		else
458 			gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
459 
460 #ifdef CONFIG_PARTITION_TYPE_GUID
461 		str_type_guid = partitions[i].type_guid;
462 		bin_type_guid = gpt_e[i].partition_type_guid.b;
463 		if (strlen(str_type_guid)) {
464 			if (uuid_str_to_bin(str_type_guid, bin_type_guid,
465 					    UUID_STR_FORMAT_GUID)) {
466 				printf("Partition no. %d: invalid type guid: %s\n",
467 				       i, str_type_guid);
468 				return -1;
469 			}
470 		} else {
471 			/* default partition type GUID */
472 			memcpy(bin_type_guid,
473 			       &PARTITION_BASIC_DATA_GUID, 16);
474 		}
475 #else
476 		/* partition type GUID */
477 		memcpy(gpt_e[i].partition_type_guid.b,
478 			&PARTITION_BASIC_DATA_GUID, 16);
479 #endif
480 
481 #ifdef CONFIG_PARTITION_UUIDS
482 		str_uuid = partitions[i].uuid;
483 		bin_uuid = gpt_e[i].unique_partition_guid.b;
484 
485 		if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_STD)) {
486 			printf("Partition no. %d: invalid guid: %s\n",
487 				i, str_uuid);
488 			return -1;
489 		}
490 #endif
491 
492 		/* partition attributes */
493 		memset(&gpt_e[i].attributes, 0,
494 		       sizeof(gpt_entry_attributes));
495 
496 		if (partitions[i].bootable)
497 			gpt_e[i].attributes.fields.legacy_bios_bootable = 1;
498 
499 		/* partition name */
500 		efiname_len = sizeof(gpt_e[i].partition_name)
501 			/ sizeof(efi_char16_t);
502 		dosname_len = sizeof(partitions[i].name);
503 
504 		memset(gpt_e[i].partition_name, 0,
505 		       sizeof(gpt_e[i].partition_name));
506 
507 		for (k = 0; k < min(dosname_len, efiname_len); k++)
508 			gpt_e[i].partition_name[k] =
509 				(efi_char16_t)(partitions[i].name[k]);
510 
511 		debug("%s: name: %s offset[%d]: 0x" LBAF
512 		      " size[%d]: 0x" LBAF "\n",
513 		      __func__, partitions[i].name, i,
514 		      offset, i, partitions[i].size);
515 	}
516 
517 	return 0;
518 }
519 
520 int gpt_fill_header(block_dev_desc_t *dev_desc, gpt_header *gpt_h,
521 		char *str_guid, int parts_count)
522 {
523 	gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
524 	gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
525 	gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
526 	gpt_h->my_lba = cpu_to_le64(1);
527 	gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
528 	gpt_h->first_usable_lba = cpu_to_le64(34);
529 	gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
530 	gpt_h->partition_entry_lba = cpu_to_le64(2);
531 	gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
532 	gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
533 	gpt_h->header_crc32 = 0;
534 	gpt_h->partition_entry_array_crc32 = 0;
535 
536 	if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
537 		return -1;
538 
539 	return 0;
540 }
541 
542 int gpt_restore(block_dev_desc_t *dev_desc, char *str_disk_guid,
543 		disk_partition_t *partitions, int parts_count)
544 {
545 	int ret;
546 
547 	gpt_header *gpt_h = calloc(1, PAD_TO_BLOCKSIZE(sizeof(gpt_header),
548 						       dev_desc));
549 	gpt_entry *gpt_e;
550 
551 	if (gpt_h == NULL) {
552 		printf("%s: calloc failed!\n", __func__);
553 		return -1;
554 	}
555 
556 	gpt_e = calloc(1, PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS
557 					       * sizeof(gpt_entry),
558 					       dev_desc));
559 	if (gpt_e == NULL) {
560 		printf("%s: calloc failed!\n", __func__);
561 		free(gpt_h);
562 		return -1;
563 	}
564 
565 	/* Generate Primary GPT header (LBA1) */
566 	ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
567 	if (ret)
568 		goto err;
569 
570 	/* Generate partition entries */
571 	ret = gpt_fill_pte(gpt_h, gpt_e, partitions, parts_count);
572 	if (ret)
573 		goto err;
574 
575 	/* Write GPT partition table */
576 	ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
577 
578 err:
579 	free(gpt_e);
580 	free(gpt_h);
581 	return ret;
582 }
583 
584 static void gpt_convert_efi_name_to_char(char *s, efi_char16_t *es, int n)
585 {
586 	char *ess = (char *)es;
587 	int i, j;
588 
589 	memset(s, '\0', n);
590 
591 	for (i = 0, j = 0; j < n; i += 2, j++) {
592 		s[j] = ess[i];
593 		if (!ess[i])
594 			return;
595 	}
596 }
597 
598 int gpt_verify_headers(block_dev_desc_t *dev_desc, gpt_header *gpt_head,
599 		       gpt_entry **gpt_pte)
600 {
601 	/*
602 	 * This function validates AND
603 	 * fills in the GPT header and PTE
604 	 */
605 	if (is_gpt_valid(dev_desc,
606 			 GPT_PRIMARY_PARTITION_TABLE_LBA,
607 			 gpt_head, gpt_pte) != 1) {
608 		printf("%s: *** ERROR: Invalid GPT ***\n",
609 		       __func__);
610 		return -1;
611 	}
612 	if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
613 			 gpt_head, gpt_pte) != 1) {
614 		printf("%s: *** ERROR: Invalid Backup GPT ***\n",
615 		       __func__);
616 		return -1;
617 	}
618 
619 	return 0;
620 }
621 
622 int gpt_verify_partitions(block_dev_desc_t *dev_desc,
623 			  disk_partition_t *partitions, int parts,
624 			  gpt_header *gpt_head, gpt_entry **gpt_pte)
625 {
626 	char efi_str[PARTNAME_SZ + 1];
627 	u64 gpt_part_size;
628 	gpt_entry *gpt_e;
629 	int ret, i;
630 
631 	ret = gpt_verify_headers(dev_desc, gpt_head, gpt_pte);
632 	if (ret)
633 		return ret;
634 
635 	gpt_e = *gpt_pte;
636 
637 	for (i = 0; i < parts; i++) {
638 		if (i == gpt_head->num_partition_entries) {
639 			error("More partitions than allowed!\n");
640 			return -1;
641 		}
642 
643 		/* Check if GPT and ENV partition names match */
644 		gpt_convert_efi_name_to_char(efi_str, gpt_e[i].partition_name,
645 					     PARTNAME_SZ + 1);
646 
647 		debug("%s: part: %2d name - GPT: %16s, ENV: %16s ",
648 		      __func__, i, efi_str, partitions[i].name);
649 
650 		if (strncmp(efi_str, (char *)partitions[i].name,
651 			    sizeof(partitions->name))) {
652 			error("Partition name: %s does not match %s!\n",
653 			      efi_str, (char *)partitions[i].name);
654 			return -1;
655 		}
656 
657 		/* Check if GPT and ENV sizes match */
658 		gpt_part_size = le64_to_cpu(gpt_e[i].ending_lba) -
659 			le64_to_cpu(gpt_e[i].starting_lba) + 1;
660 		debug("size(LBA) - GPT: %8llu, ENV: %8llu ",
661 		      gpt_part_size, (u64) partitions[i].size);
662 
663 		if (le64_to_cpu(gpt_part_size) != partitions[i].size) {
664 			error("Partition %s size: %llu does not match %llu!\n",
665 			      efi_str, gpt_part_size, (u64) partitions[i].size);
666 			return -1;
667 		}
668 
669 		/*
670 		 * Start address is optional - check only if provided
671 		 * in '$partition' variable
672 		 */
673 		if (!partitions[i].start) {
674 			debug("\n");
675 			continue;
676 		}
677 
678 		/* Check if GPT and ENV start LBAs match */
679 		debug("start LBA - GPT: %8llu, ENV: %8llu\n",
680 		      le64_to_cpu(gpt_e[i].starting_lba),
681 		      (u64) partitions[i].start);
682 
683 		if (le64_to_cpu(gpt_e[i].starting_lba) != partitions[i].start) {
684 			error("Partition %s start: %llu does not match %llu!\n",
685 			      efi_str, le64_to_cpu(gpt_e[i].starting_lba),
686 			      (u64) partitions[i].start);
687 			return -1;
688 		}
689 	}
690 
691 	return 0;
692 }
693 
694 int is_valid_gpt_buf(block_dev_desc_t *dev_desc, void *buf)
695 {
696 	gpt_header *gpt_h;
697 	gpt_entry *gpt_e;
698 
699 	/* determine start of GPT Header in the buffer */
700 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
701 		       dev_desc->blksz);
702 	if (validate_gpt_header(gpt_h, GPT_PRIMARY_PARTITION_TABLE_LBA,
703 				dev_desc->lba))
704 		return -1;
705 
706 	/* determine start of GPT Entries in the buffer */
707 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
708 		       dev_desc->blksz);
709 	if (validate_gpt_entries(gpt_h, gpt_e))
710 		return -1;
711 
712 	return 0;
713 }
714 
715 int write_mbr_and_gpt_partitions(block_dev_desc_t *dev_desc, void *buf)
716 {
717 	gpt_header *gpt_h;
718 	gpt_entry *gpt_e;
719 	int gpt_e_blk_cnt;
720 	lbaint_t lba;
721 	int cnt;
722 
723 	if (is_valid_gpt_buf(dev_desc, buf))
724 		return -1;
725 
726 	/* determine start of GPT Header in the buffer */
727 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
728 		       dev_desc->blksz);
729 
730 	/* determine start of GPT Entries in the buffer */
731 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
732 		       dev_desc->blksz);
733 	gpt_e_blk_cnt = BLOCK_CNT((le32_to_cpu(gpt_h->num_partition_entries) *
734 				   le32_to_cpu(gpt_h->sizeof_partition_entry)),
735 				  dev_desc);
736 
737 	/* write MBR */
738 	lba = 0;	/* MBR is always at 0 */
739 	cnt = 1;	/* MBR (1 block) */
740 	if (dev_desc->block_write(dev_desc, lba, cnt, buf) != cnt) {
741 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
742 		       __func__, "MBR", cnt, lba);
743 		return 1;
744 	}
745 
746 	/* write Primary GPT */
747 	lba = GPT_PRIMARY_PARTITION_TABLE_LBA;
748 	cnt = 1;	/* GPT Header (1 block) */
749 	if (dev_desc->block_write(dev_desc, lba, cnt, gpt_h) != cnt) {
750 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
751 		       __func__, "Primary GPT Header", cnt, lba);
752 		return 1;
753 	}
754 
755 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
756 	cnt = gpt_e_blk_cnt;
757 	if (dev_desc->block_write(dev_desc, lba, cnt, gpt_e) != cnt) {
758 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
759 		       __func__, "Primary GPT Entries", cnt, lba);
760 		return 1;
761 	}
762 
763 	prepare_backup_gpt_header(gpt_h);
764 
765 	/* write Backup GPT */
766 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
767 	cnt = gpt_e_blk_cnt;
768 	if (dev_desc->block_write(dev_desc, lba, cnt, gpt_e) != cnt) {
769 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
770 		       __func__, "Backup GPT Entries", cnt, lba);
771 		return 1;
772 	}
773 
774 	lba = le64_to_cpu(gpt_h->my_lba);
775 	cnt = 1;	/* GPT Header (1 block) */
776 	if (dev_desc->block_write(dev_desc, lba, cnt, gpt_h) != cnt) {
777 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
778 		       __func__, "Backup GPT Header", cnt, lba);
779 		return 1;
780 	}
781 
782 	return 0;
783 }
784 #endif
785 
786 /*
787  * Private functions
788  */
789 /*
790  * pmbr_part_valid(): Check for EFI partition signature
791  *
792  * Returns: 1 if EFI GPT partition type is found.
793  */
794 static int pmbr_part_valid(struct partition *part)
795 {
796 	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
797 		get_unaligned_le32(&part->start_sect) == 1UL) {
798 		return 1;
799 	}
800 
801 	return 0;
802 }
803 
804 /*
805  * is_pmbr_valid(): test Protective MBR for validity
806  *
807  * Returns: 1 if PMBR is valid, 0 otherwise.
808  * Validity depends on two things:
809  *  1) MSDOS signature is in the last two bytes of the MBR
810  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
811  */
812 static int is_pmbr_valid(legacy_mbr * mbr)
813 {
814 	int i = 0;
815 
816 	if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
817 		return 0;
818 
819 	for (i = 0; i < 4; i++) {
820 		if (pmbr_part_valid(&mbr->partition_record[i])) {
821 			return 1;
822 		}
823 	}
824 	return 0;
825 }
826 
827 /**
828  * is_gpt_valid() - tests one GPT header and PTEs for validity
829  *
830  * lba is the logical block address of the GPT header to test
831  * gpt is a GPT header ptr, filled on return.
832  * ptes is a PTEs ptr, filled on return.
833  *
834  * Description: returns 1 if valid,  0 on error.
835  * If valid, returns pointers to PTEs.
836  */
837 static int is_gpt_valid(block_dev_desc_t *dev_desc, u64 lba,
838 			gpt_header *pgpt_head, gpt_entry **pgpt_pte)
839 {
840 	if (!dev_desc || !pgpt_head) {
841 		printf("%s: Invalid Argument(s)\n", __func__);
842 		return 0;
843 	}
844 
845 	/* Read GPT Header from device */
846 	if (dev_desc->block_read(dev_desc, (lbaint_t)lba, 1, pgpt_head) != 1) {
847 		printf("*** ERROR: Can't read GPT header ***\n");
848 		return 0;
849 	}
850 
851 	if (validate_gpt_header(pgpt_head, (lbaint_t)lba, dev_desc->lba))
852 		return 0;
853 
854 	/* Read and allocate Partition Table Entries */
855 	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
856 	if (*pgpt_pte == NULL) {
857 		printf("GPT: Failed to allocate memory for PTE\n");
858 		return 0;
859 	}
860 
861 	if (validate_gpt_entries(pgpt_head, *pgpt_pte)) {
862 		free(*pgpt_pte);
863 		return 0;
864 	}
865 
866 	/* We're done, all's well */
867 	return 1;
868 }
869 
870 /**
871  * alloc_read_gpt_entries(): reads partition entries from disk
872  * @dev_desc
873  * @gpt - GPT header
874  *
875  * Description: Returns ptes on success,  NULL on error.
876  * Allocates space for PTEs based on information found in @gpt.
877  * Notes: remember to free pte when you're done!
878  */
879 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
880 					 gpt_header * pgpt_head)
881 {
882 	size_t count = 0, blk_cnt;
883 	lbaint_t blk;
884 	gpt_entry *pte = NULL;
885 
886 	if (!dev_desc || !pgpt_head) {
887 		printf("%s: Invalid Argument(s)\n", __func__);
888 		return NULL;
889 	}
890 
891 	count = le32_to_cpu(pgpt_head->num_partition_entries) *
892 		le32_to_cpu(pgpt_head->sizeof_partition_entry);
893 
894 	debug("%s: count = %u * %u = %zu\n", __func__,
895 	      (u32) le32_to_cpu(pgpt_head->num_partition_entries),
896 	      (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry), count);
897 
898 	/* Allocate memory for PTE, remember to FREE */
899 	if (count != 0) {
900 		pte = memalign(ARCH_DMA_MINALIGN,
901 			       PAD_TO_BLOCKSIZE(count, dev_desc));
902 	}
903 
904 	if (count == 0 || pte == NULL) {
905 		printf("%s: ERROR: Can't allocate 0x%zX "
906 		       "bytes for GPT Entries\n",
907 			__func__, count);
908 		return NULL;
909 	}
910 
911 	/* Read GPT Entries from device */
912 	blk = le64_to_cpu(pgpt_head->partition_entry_lba);
913 	blk_cnt = BLOCK_CNT(count, dev_desc);
914 	if (dev_desc->block_read(dev_desc, blk, (lbaint_t)blk_cnt, pte)
915 	    != blk_cnt) {
916 		printf("*** ERROR: Can't read GPT Entries ***\n");
917 		free(pte);
918 		return NULL;
919 	}
920 	return pte;
921 }
922 
923 /**
924  * is_pte_valid(): validates a single Partition Table Entry
925  * @gpt_entry - Pointer to a single Partition Table Entry
926  *
927  * Description: returns 1 if valid,  0 on error.
928  */
929 static int is_pte_valid(gpt_entry * pte)
930 {
931 	efi_guid_t unused_guid;
932 
933 	if (!pte) {
934 		printf("%s: Invalid Argument(s)\n", __func__);
935 		return 0;
936 	}
937 
938 	/* Only one validation for now:
939 	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
940 	 */
941 	memset(unused_guid.b, 0, sizeof(unused_guid.b));
942 
943 	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
944 		sizeof(unused_guid.b)) == 0) {
945 
946 		debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
947 		      (unsigned int)(uintptr_t)pte);
948 
949 		return 0;
950 	} else {
951 		return 1;
952 	}
953 }
954 #endif
955