xref: /openbmc/u-boot/disk/part_efi.c (revision 702e6014)
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 #include <linux/ctype.h>
39 
40 #if defined(CONFIG_CMD_IDE) || \
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 static char *print_efiname(gpt_entry *pte)
103 {
104 	static char name[PARTNAME_SZ + 1];
105 	int i;
106 	for (i = 0; i < PARTNAME_SZ; i++) {
107 		u8 c;
108 		c = pte->partition_name[i] & 0xff;
109 		c = (c && !isprint(c)) ? '.' : c;
110 		name[i] = c;
111 	}
112 	name[PARTNAME_SZ] = 0;
113 	return name;
114 }
115 
116 /*
117  * Public Functions (include/part.h)
118  */
119 
120 void print_part_efi(block_dev_desc_t * dev_desc)
121 {
122 	ALLOC_CACHE_ALIGN_BUFFER(gpt_header, gpt_head, 1);
123 	gpt_entry *gpt_pte = NULL;
124 	int i = 0;
125 
126 	if (!dev_desc) {
127 		printf("%s: Invalid Argument(s)\n", __func__);
128 		return;
129 	}
130 	/* This function validates AND fills in the GPT header and PTE */
131 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
132 			 gpt_head, &gpt_pte) != 1) {
133 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
134 		return;
135 	}
136 
137 	debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
138 
139 	printf("Part\tName\t\t\tStart LBA\tEnd LBA\n");
140 	for (i = 0; i < le32_to_int(gpt_head->num_partition_entries); i++) {
141 
142 		if (is_pte_valid(&gpt_pte[i])) {
143 			printf("%3d\t%-18s\t0x%08llX\t0x%08llX\n", (i + 1),
144 				print_efiname(&gpt_pte[i]),
145 				le64_to_int(gpt_pte[i].starting_lba),
146 				le64_to_int(gpt_pte[i].ending_lba));
147 		} else {
148 			break;	/* Stop at the first non valid PTE */
149 		}
150 	}
151 
152 	/* Remember to free pte */
153 	free(gpt_pte);
154 	return;
155 }
156 
157 int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
158 				disk_partition_t * info)
159 {
160 	ALLOC_CACHE_ALIGN_BUFFER(gpt_header, gpt_head, 1);
161 	gpt_entry *gpt_pte = NULL;
162 
163 	/* "part" argument must be at least 1 */
164 	if (!dev_desc || !info || part < 1) {
165 		printf("%s: Invalid Argument(s)\n", __func__);
166 		return -1;
167 	}
168 
169 	/* This function validates AND fills in the GPT header and PTE */
170 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
171 			gpt_head, &gpt_pte) != 1) {
172 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
173 		return -1;
174 	}
175 
176 	/* The ulong casting limits the maximum disk size to 2 TB */
177 	info->start = (ulong) le64_to_int(gpt_pte[part - 1].starting_lba);
178 	/* The ending LBA is inclusive, to calculate size, add 1 to it */
179 	info->size = ((ulong)le64_to_int(gpt_pte[part - 1].ending_lba) + 1)
180 		     - info->start;
181 	info->blksz = GPT_BLOCK_SIZE;
182 
183 	sprintf((char *)info->name, "%s",
184 			print_efiname(&gpt_pte[part - 1]));
185 	sprintf((char *)info->type, "U-Boot");
186 
187 	debug("%s: start 0x%lX, size 0x%lX, name %s", __func__,
188 		info->start, info->size, info->name);
189 
190 	/* Remember to free pte */
191 	free(gpt_pte);
192 	return 0;
193 }
194 
195 int test_part_efi(block_dev_desc_t * dev_desc)
196 {
197 	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, legacymbr, 1);
198 
199 	/* Read legacy MBR from block 0 and validate it */
200 	if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)legacymbr) != 1)
201 		|| (is_pmbr_valid(legacymbr) != 1)) {
202 		return -1;
203 	}
204 	return 0;
205 }
206 
207 /*
208  * Private functions
209  */
210 /*
211  * pmbr_part_valid(): Check for EFI partition signature
212  *
213  * Returns: 1 if EFI GPT partition type is found.
214  */
215 static int pmbr_part_valid(struct partition *part)
216 {
217 	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
218 		le32_to_int(part->start_sect) == 1UL) {
219 		return 1;
220 	}
221 
222 	return 0;
223 }
224 
225 /*
226  * is_pmbr_valid(): test Protective MBR for validity
227  *
228  * Returns: 1 if PMBR is valid, 0 otherwise.
229  * Validity depends on two things:
230  *  1) MSDOS signature is in the last two bytes of the MBR
231  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
232  */
233 static int is_pmbr_valid(legacy_mbr * mbr)
234 {
235 	int i = 0;
236 
237 	if (!mbr || le16_to_int(mbr->signature) != MSDOS_MBR_SIGNATURE) {
238 		return 0;
239 	}
240 
241 	for (i = 0; i < 4; i++) {
242 		if (pmbr_part_valid(&mbr->partition_record[i])) {
243 			return 1;
244 		}
245 	}
246 	return 0;
247 }
248 
249 /**
250  * is_gpt_valid() - tests one GPT header and PTEs for validity
251  *
252  * lba is the logical block address of the GPT header to test
253  * gpt is a GPT header ptr, filled on return.
254  * ptes is a PTEs ptr, filled on return.
255  *
256  * Description: returns 1 if valid,  0 on error.
257  * If valid, returns pointers to PTEs.
258  */
259 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
260 			gpt_header * pgpt_head, gpt_entry ** pgpt_pte)
261 {
262 	unsigned char crc32_backup[4] = { 0 };
263 	unsigned long calc_crc32;
264 	unsigned long long lastlba;
265 
266 	if (!dev_desc || !pgpt_head) {
267 		printf("%s: Invalid Argument(s)\n", __func__);
268 		return 0;
269 	}
270 
271 	/* Read GPT Header from device */
272 	if (dev_desc->block_read(dev_desc->dev, lba, 1, pgpt_head) != 1) {
273 		printf("*** ERROR: Can't read GPT header ***\n");
274 		return 0;
275 	}
276 
277 	/* Check the GPT header signature */
278 	if (le64_to_int(pgpt_head->signature) != GPT_HEADER_SIGNATURE) {
279 		printf("GUID Partition Table Header signature is wrong:"
280 			"0x%llX != 0x%llX\n",
281 			(unsigned long long)le64_to_int(pgpt_head->signature),
282 			(unsigned long long)GPT_HEADER_SIGNATURE);
283 		return 0;
284 	}
285 
286 	/* Check the GUID Partition Table CRC */
287 	memcpy(crc32_backup, pgpt_head->header_crc32, sizeof(crc32_backup));
288 	memset(pgpt_head->header_crc32, 0, sizeof(pgpt_head->header_crc32));
289 
290 	calc_crc32 = efi_crc32((const unsigned char *)pgpt_head,
291 		le32_to_int(pgpt_head->header_size));
292 
293 	memcpy(pgpt_head->header_crc32, crc32_backup, sizeof(crc32_backup));
294 
295 	if (calc_crc32 != le32_to_int(crc32_backup)) {
296 		printf("GUID Partition Table Header CRC is wrong:"
297 			"0x%08lX != 0x%08lX\n",
298 			le32_to_int(crc32_backup), calc_crc32);
299 		return 0;
300 	}
301 
302 	/* Check that the my_lba entry points to the LBA that contains the GPT */
303 	if (le64_to_int(pgpt_head->my_lba) != lba) {
304 		printf("GPT: my_lba incorrect: %llX != %llX\n",
305 			(unsigned long long)le64_to_int(pgpt_head->my_lba),
306 			(unsigned long long)lba);
307 		return 0;
308 	}
309 
310 	/* Check the first_usable_lba and last_usable_lba are within the disk. */
311 	lastlba = (unsigned long long)dev_desc->lba;
312 	if (le64_to_int(pgpt_head->first_usable_lba) > lastlba) {
313 		printf("GPT: first_usable_lba incorrect: %llX > %llX\n",
314 			le64_to_int(pgpt_head->first_usable_lba), lastlba);
315 		return 0;
316 	}
317 	if (le64_to_int(pgpt_head->last_usable_lba) > lastlba) {
318 		printf("GPT: last_usable_lba incorrect: %llX > %llX\n",
319 			le64_to_int(pgpt_head->last_usable_lba), lastlba);
320 		return 0;
321 	}
322 
323 	debug("GPT: first_usable_lba: %llX last_usable_lba %llX last lba %llX\n",
324 		le64_to_int(pgpt_head->first_usable_lba),
325 		le64_to_int(pgpt_head->last_usable_lba), lastlba);
326 
327 	/* Read and allocate Partition Table Entries */
328 	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
329 	if (*pgpt_pte == NULL) {
330 		printf("GPT: Failed to allocate memory for PTE\n");
331 		return 0;
332 	}
333 
334 	/* Check the GUID Partition Table Entry Array CRC */
335 	calc_crc32 = efi_crc32((const unsigned char *)*pgpt_pte,
336 		le32_to_int(pgpt_head->num_partition_entries) *
337 		le32_to_int(pgpt_head->sizeof_partition_entry));
338 
339 	if (calc_crc32 != le32_to_int(pgpt_head->partition_entry_array_crc32)) {
340 		printf("GUID Partition Table Entry Array CRC is wrong:"
341 			"0x%08lX != 0x%08lX\n",
342 			le32_to_int(pgpt_head->partition_entry_array_crc32),
343 			calc_crc32);
344 
345 		free(*pgpt_pte);
346 		return 0;
347 	}
348 
349 	/* We're done, all's well */
350 	return 1;
351 }
352 
353 /**
354  * alloc_read_gpt_entries(): reads partition entries from disk
355  * @dev_desc
356  * @gpt - GPT header
357  *
358  * Description: Returns ptes on success,  NULL on error.
359  * Allocates space for PTEs based on information found in @gpt.
360  * Notes: remember to free pte when you're done!
361  */
362 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
363 					 gpt_header * pgpt_head)
364 {
365 	size_t count = 0;
366 	gpt_entry *pte = NULL;
367 
368 	if (!dev_desc || !pgpt_head) {
369 		printf("%s: Invalid Argument(s)\n", __func__);
370 		return NULL;
371 	}
372 
373 	count = le32_to_int(pgpt_head->num_partition_entries) *
374 		le32_to_int(pgpt_head->sizeof_partition_entry);
375 
376 	debug("%s: count = %lu * %lu = %u\n", __func__,
377 		le32_to_int(pgpt_head->num_partition_entries),
378 		le32_to_int(pgpt_head->sizeof_partition_entry), count);
379 
380 	/* Allocate memory for PTE, remember to FREE */
381 	if (count != 0) {
382 		pte = memalign(ARCH_DMA_MINALIGN, count);
383 	}
384 
385 	if (count == 0 || pte == NULL) {
386 		printf("%s: ERROR: Can't allocate 0x%X bytes for GPT Entries\n",
387 			__func__, count);
388 		return NULL;
389 	}
390 
391 	/* Read GPT Entries from device */
392 	if (dev_desc->block_read (dev_desc->dev,
393 		(unsigned long)le64_to_int(pgpt_head->partition_entry_lba),
394 		(lbaint_t) (count / GPT_BLOCK_SIZE), pte)
395 		!= (count / GPT_BLOCK_SIZE)) {
396 
397 		printf("*** ERROR: Can't read GPT Entries ***\n");
398 		free(pte);
399 		return NULL;
400 	}
401 	return pte;
402 }
403 
404 /**
405  * is_pte_valid(): validates a single Partition Table Entry
406  * @gpt_entry - Pointer to a single Partition Table Entry
407  *
408  * Description: returns 1 if valid,  0 on error.
409  */
410 static int is_pte_valid(gpt_entry * pte)
411 {
412 	efi_guid_t unused_guid;
413 
414 	if (!pte) {
415 		printf("%s: Invalid Argument(s)\n", __func__);
416 		return 0;
417 	}
418 
419 	/* Only one validation for now:
420 	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
421 	 */
422 	memset(unused_guid.b, 0, sizeof(unused_guid.b));
423 
424 	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
425 		sizeof(unused_guid.b)) == 0) {
426 
427 		debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
428 		(unsigned int)pte);
429 
430 		return 0;
431 	} else {
432 		return 1;
433 	}
434 }
435 #endif
436