xref: /openbmc/u-boot/disk/part_efi.c (revision 84bf7ca5)
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_MG_DISK) || \
41     defined(CONFIG_CMD_SATA) || \
42     defined(CONFIG_CMD_SCSI) || \
43     defined(CONFIG_CMD_USB) || \
44     defined(CONFIG_MMC) || \
45     defined(CONFIG_SYSTEMACE)
46 
47 /* Convert char[2] in little endian format to the host format integer
48  */
49 static inline unsigned short le16_to_int(unsigned char *le16)
50 {
51 	return ((le16[1] << 8) + le16[0]);
52 }
53 
54 /* Convert char[4] in little endian format to the host format integer
55  */
56 static inline unsigned long le32_to_int(unsigned char *le32)
57 {
58 	return ((le32[3] << 24) + (le32[2] << 16) + (le32[1] << 8) + le32[0]);
59 }
60 
61 /* Convert char[8] in little endian format to the host format integer
62  */
63 static inline unsigned long long le64_to_int(unsigned char *le64)
64 {
65 	return (((unsigned long long)le64[7] << 56) +
66 		((unsigned long long)le64[6] << 48) +
67 		((unsigned long long)le64[5] << 40) +
68 		((unsigned long long)le64[4] << 32) +
69 		((unsigned long long)le64[3] << 24) +
70 		((unsigned long long)le64[2] << 16) +
71 		((unsigned long long)le64[1] << 8) +
72 		(unsigned long long)le64[0]);
73 }
74 
75 /**
76  * efi_crc32() - EFI version of crc32 function
77  * @buf: buffer to calculate crc32 of
78  * @len - length of buf
79  *
80  * Description: Returns EFI-style CRC32 value for @buf
81  */
82 static inline unsigned long efi_crc32(const void *buf, unsigned long len)
83 {
84 	return crc32(0, buf, len);
85 }
86 
87 /*
88  * Private function prototypes
89  */
90 
91 static int pmbr_part_valid(struct partition *part);
92 static int is_pmbr_valid(legacy_mbr * mbr);
93 
94 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
95 				gpt_header * pgpt_head, gpt_entry ** pgpt_pte);
96 
97 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
98 				gpt_header * pgpt_head);
99 
100 static int is_pte_valid(gpt_entry * pte);
101 
102 /*
103  * Public Functions (include/part.h)
104  */
105 
106 void print_part_efi(block_dev_desc_t * dev_desc)
107 {
108 	gpt_header gpt_head;
109 	gpt_entry **pgpt_pte = NULL;
110 	int i = 0;
111 
112 	if (!dev_desc) {
113 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
114 		return;
115 	}
116 	/* This function validates AND fills in the GPT header and PTE */
117 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
118 			 &(gpt_head), pgpt_pte) != 1) {
119 		printf("%s: *** ERROR: Invalid GPT ***\n", __FUNCTION__);
120 		return;
121 	}
122 
123 	debug("%s: gpt-entry at 0x%08X\n", __FUNCTION__, (unsigned int)*pgpt_pte);
124 
125 	printf("Part  Start LBA  End LBA\n");
126 	for (i = 0; i < le32_to_int(gpt_head.num_partition_entries); i++) {
127 
128 		if (is_pte_valid(&(*pgpt_pte)[i])) {
129 			printf("%s%d  0x%llX    0x%llX\n", GPT_ENTRY_NAME,
130 				(i + 1),
131 				le64_to_int((*pgpt_pte)[i].starting_lba),
132 				le64_to_int((*pgpt_pte)[i].ending_lba));
133 		} else {
134 			break;	/* Stop at the first non valid PTE */
135 		}
136 	}
137 
138 	/* Remember to free pte */
139 	if (*pgpt_pte != NULL) {
140 		debug("%s: Freeing pgpt_pte\n", __FUNCTION__);
141 		free(*pgpt_pte);
142 	}
143 	return;
144 }
145 
146 int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
147 				disk_partition_t * info)
148 {
149 	gpt_header gpt_head;
150 	gpt_entry **pgpt_pte = NULL;
151 
152 	/* "part" argument must be at least 1 */
153 	if (!dev_desc || !info || part < 1) {
154 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
155 		return -1;
156 	}
157 
158 	/* This function validates AND fills in the GPT header and PTE */
159 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
160 			&(gpt_head), pgpt_pte) != 1) {
161 		printf("%s: *** ERROR: Invalid GPT ***\n", __FUNCTION__);
162 		return -1;
163 	}
164 
165 	/* The ulong casting limits the maximum disk size to 2 TB */
166 	info->start = (ulong) le64_to_int((*pgpt_pte)[part - 1].starting_lba);
167 	/* The ending LBA is inclusive, to calculate size, add 1 to it */
168 	info->size = ((ulong)le64_to_int((*pgpt_pte)[part - 1].ending_lba) + 1)
169 		     - info->start;
170 	info->blksz = GPT_BLOCK_SIZE;
171 
172 	sprintf((char *)info->name, "%s%d\n", GPT_ENTRY_NAME, part);
173 	sprintf((char *)info->type, "U-Boot");
174 
175 	debug("%s: start 0x%lX, size 0x%lX, name %s", __FUNCTION__,
176 		info->start, info->size, info->name);
177 
178 	/* Remember to free pte */
179 	if (*pgpt_pte != NULL) {
180 		debug("%s: Freeing pgpt_pte\n", __FUNCTION__);
181 		free(*pgpt_pte);
182 	}
183 	return 0;
184 }
185 
186 int test_part_efi(block_dev_desc_t * dev_desc)
187 {
188 	legacy_mbr legacymbr;
189 
190 	/* Read legacy MBR from block 0 and validate it */
191 	if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *) & legacymbr) != 1)
192 		|| (is_pmbr_valid(&legacymbr) != 1)) {
193 		return -1;
194 	}
195 	return 0;
196 }
197 
198 /*
199  * Private functions
200  */
201 /*
202  * pmbr_part_valid(): Check for EFI partition signature
203  *
204  * Returns: 1 if EFI GPT partition type is found.
205  */
206 static int pmbr_part_valid(struct partition *part)
207 {
208 	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
209 		le32_to_int(part->start_sect) == 1UL) {
210 		return 1;
211 	}
212 
213 	return 0;
214 }
215 
216 /*
217  * is_pmbr_valid(): test Protective MBR for validity
218  *
219  * Returns: 1 if PMBR is valid, 0 otherwise.
220  * Validity depends on two things:
221  *  1) MSDOS signature is in the last two bytes of the MBR
222  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
223  */
224 static int is_pmbr_valid(legacy_mbr * mbr)
225 {
226 	int i = 0;
227 
228 	if (!mbr || le16_to_int(mbr->signature) != MSDOS_MBR_SIGNATURE) {
229 		return 0;
230 	}
231 
232 	for (i = 0; i < 4; i++) {
233 		if (pmbr_part_valid(&mbr->partition_record[i])) {
234 			return 1;
235 		}
236 	}
237 	return 0;
238 }
239 
240 /**
241  * is_gpt_valid() - tests one GPT header and PTEs for validity
242  *
243  * lba is the logical block address of the GPT header to test
244  * gpt is a GPT header ptr, filled on return.
245  * ptes is a PTEs ptr, filled on return.
246  *
247  * Description: returns 1 if valid,  0 on error.
248  * If valid, returns pointers to PTEs.
249  */
250 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
251 			gpt_header * pgpt_head, gpt_entry ** pgpt_pte)
252 {
253 	unsigned char crc32_backup[4] = { 0 };
254 	unsigned long calc_crc32;
255 	unsigned long long lastlba;
256 
257 	if (!dev_desc || !pgpt_head) {
258 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
259 		return 0;
260 	}
261 
262 	/* Read GPT Header from device */
263 	if (dev_desc->block_read(dev_desc->dev, lba, 1, pgpt_head) != 1) {
264 		printf("*** ERROR: Can't read GPT header ***\n");
265 		return 0;
266 	}
267 
268 	/* Check the GPT header signature */
269 	if (le64_to_int(pgpt_head->signature) != GPT_HEADER_SIGNATURE) {
270 		printf("GUID Partition Table Header signature is wrong:"
271 			"0x%llX != 0x%llX\n",
272 			(unsigned long long)le64_to_int(pgpt_head->signature),
273 			(unsigned long long)GPT_HEADER_SIGNATURE);
274 		return 0;
275 	}
276 
277 	/* Check the GUID Partition Table CRC */
278 	memcpy(crc32_backup, pgpt_head->header_crc32, sizeof(crc32_backup));
279 	memset(pgpt_head->header_crc32, 0, sizeof(pgpt_head->header_crc32));
280 
281 	calc_crc32 = efi_crc32((const unsigned char *)pgpt_head,
282 		le32_to_int(pgpt_head->header_size));
283 
284 	memcpy(pgpt_head->header_crc32, crc32_backup, sizeof(crc32_backup));
285 
286 	if (calc_crc32 != le32_to_int(crc32_backup)) {
287 		printf("GUID Partition Table Header CRC is wrong:"
288 			"0x%08lX != 0x%08lX\n",
289 			le32_to_int(crc32_backup), calc_crc32);
290 		return 0;
291 	}
292 
293 	/* Check that the my_lba entry points to the LBA that contains the GPT */
294 	if (le64_to_int(pgpt_head->my_lba) != lba) {
295 		printf("GPT: my_lba incorrect: %llX != %llX\n",
296 			(unsigned long long)le64_to_int(pgpt_head->my_lba),
297 			(unsigned long long)lba);
298 		return 0;
299 	}
300 
301 	/* Check the first_usable_lba and last_usable_lba are within the disk. */
302 	lastlba = (unsigned long long)dev_desc->lba;
303 	if (le64_to_int(pgpt_head->first_usable_lba) > lastlba) {
304 		printf("GPT: first_usable_lba incorrect: %llX > %llX\n",
305 			le64_to_int(pgpt_head->first_usable_lba), lastlba);
306 		return 0;
307 	}
308 	if (le64_to_int(pgpt_head->last_usable_lba) > lastlba) {
309 		printf("GPT: last_usable_lba incorrect: %llX > %llX\n",
310 			le64_to_int(pgpt_head->last_usable_lba), lastlba);
311 		return 0;
312 	}
313 
314 	debug("GPT: first_usable_lba: %llX last_usable_lba %llX last lba %llX\n",
315 		le64_to_int(pgpt_head->first_usable_lba),
316 		le64_to_int(pgpt_head->last_usable_lba), lastlba);
317 
318 	/* Read and allocate Partition Table Entries */
319 	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
320 	if (*pgpt_pte == NULL) {
321 		printf("GPT: Failed to allocate memory for PTE\n");
322 		return 0;
323 	}
324 
325 	/* Check the GUID Partition Table Entry Array CRC */
326 	calc_crc32 = efi_crc32((const unsigned char *)*pgpt_pte,
327 		le32_to_int(pgpt_head->num_partition_entries) *
328 		le32_to_int(pgpt_head->sizeof_partition_entry));
329 
330 	if (calc_crc32 != le32_to_int(pgpt_head->partition_entry_array_crc32)) {
331 		printf("GUID Partition Table Entry Array CRC is wrong:"
332 			"0x%08lX != 0x%08lX\n",
333 			le32_to_int(pgpt_head->partition_entry_array_crc32),
334 			calc_crc32);
335 
336 		if (*pgpt_pte != NULL) {
337 			free(*pgpt_pte);
338 		}
339 		return 0;
340 	}
341 
342 	/* We're done, all's well */
343 	return 1;
344 }
345 
346 /**
347  * alloc_read_gpt_entries(): reads partition entries from disk
348  * @dev_desc
349  * @gpt - GPT header
350  *
351  * Description: Returns ptes on success,  NULL on error.
352  * Allocates space for PTEs based on information found in @gpt.
353  * Notes: remember to free pte when you're done!
354  */
355 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
356 					 gpt_header * pgpt_head)
357 {
358 	size_t count = 0;
359 	gpt_entry *pte = NULL;
360 
361 	if (!dev_desc || !pgpt_head) {
362 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
363 		return NULL;
364 	}
365 
366 	count = le32_to_int(pgpt_head->num_partition_entries) *
367 		le32_to_int(pgpt_head->sizeof_partition_entry);
368 
369 	debug("%s: count = %lu * %lu = %u\n", __FUNCTION__,
370 		le32_to_int(pgpt_head->num_partition_entries),
371 		le32_to_int(pgpt_head->sizeof_partition_entry), count);
372 
373 	/* Allocate memory for PTE, remember to FREE */
374 	if (count != 0) {
375 		pte = malloc(count);
376 	}
377 
378 	if (count == 0 || pte == NULL) {
379 		printf("%s: ERROR: Can't allocate 0x%X bytes for GPT Entries\n",
380 			__FUNCTION__, count);
381 		return NULL;
382 	}
383 
384 	/* Read GPT Entries from device */
385 	if (dev_desc->block_read (dev_desc->dev,
386 		(unsigned long)le64_to_int(pgpt_head->partition_entry_lba),
387 		(lbaint_t) (count / GPT_BLOCK_SIZE), pte)
388 		!= (count / GPT_BLOCK_SIZE)) {
389 
390 		printf("*** ERROR: Can't read GPT Entries ***\n");
391 		free(pte);
392 		return NULL;
393 	}
394 	return pte;
395 }
396 
397 /**
398  * is_pte_valid(): validates a single Partition Table Entry
399  * @gpt_entry - Pointer to a single Partition Table Entry
400  *
401  * Description: returns 1 if valid,  0 on error.
402  */
403 static int is_pte_valid(gpt_entry * pte)
404 {
405 	efi_guid_t unused_guid;
406 
407 	if (!pte) {
408 		printf("%s: Invalid Argument(s)\n", __FUNCTION__);
409 		return 0;
410 	}
411 
412 	/* Only one validation for now:
413 	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
414 	 */
415 	memset(unused_guid.b, 0, sizeof(unused_guid.b));
416 
417 	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
418 		sizeof(unused_guid.b)) == 0) {
419 
420 		debug("%s: Found an unused PTE GUID at 0x%08X\n", __FUNCTION__,
421 		(unsigned int)pte);
422 
423 		return 0;
424 	} else {
425 		return 1;
426 	}
427 }
428 #endif
429