summaryrefslogtreecommitdiffstats
path: root/src/commonlib/fsp_relocate.c
blob: 5d326b6290a31c26b43f37bec682ea0a5b05df5b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
/* SPDX-License-Identifier: GPL-2.0-only */

#include <console/console.h>
#include <commonlib/endian.h>
#include <commonlib/fsp.h>
/*
 * Intel's code does not have a handle on changing global packing state.
 * Therefore, one needs to protect against packing policies that are set
 * globally for a compilation unit just by including a header file.
 */
#pragma pack(push)

/* Default bind FSP 1.1 API to edk2 UEFI 2.4 types. */
#include <vendorcode/intel/edk2/uefi_2.4/uefi_types.h>
#include <vendorcode/intel/fsp/fsp1_1/IntelFspPkg/Include/FspInfoHeader.h>

/* Restore original packing policy. */
#pragma pack(pop)

#include <commonlib/helpers.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>

#define FSP_DBG_LVL BIOS_NEVER

/*
 * UEFI defines everything as little endian. However, this piece of code
 * can be integrated in a userland tool. That tool could be on a big endian
 * machine so one needs to access the fields within UEFI structures using
 * endian-aware accesses.
 */

/* Return 0 if equal. Non-zero if not equal. */
static int guid_compare(const EFI_GUID *le_guid, const EFI_GUID *native_guid)
{
	if (read_le32(&le_guid->Data1) != native_guid->Data1)
		return 1;
	if (read_le16(&le_guid->Data2) != native_guid->Data2)
		return 1;
	if (read_le16(&le_guid->Data3) != native_guid->Data3)
		return 1;
	return memcmp(le_guid->Data4, native_guid->Data4,
			ARRAY_SIZE(le_guid->Data4));
}

static const EFI_GUID ffs2_guid = EFI_FIRMWARE_FILE_SYSTEM2_GUID;
static const EFI_GUID fih_guid = FSP_INFO_HEADER_GUID;

struct fsp_patch_table {
	uint32_t signature;
	uint16_t header_length;
	uint8_t header_revision;
	uint8_t reserved;
	uint32_t patch_entry_num;
	uint32_t patch_entries[0];
} __packed;

#define FSPP_SIG 0x50505346

static void *relative_offset(void *base, ssize_t offset)
{
	uintptr_t loc;

	loc = (uintptr_t)base;
	loc += offset;

	return (void *)loc;
}

static uint32_t *fspp_reloc(void *fsp, size_t fsp_size, uint32_t e)
{
	size_t offset;

	/* Offsets live in bits 23:0. */
	offset = e & 0xffffff;

	/* If bit 31 is set then the offset is considered a negative value
	 * relative to the end of the image using 16MiB as the offset's
	 * reference. */
	if (e & (1 << 31))
		offset = fsp_size - (16 * MiB - offset);

	/* Determine if offset falls within fsp_size for a 32 bit relocation. */
	if (offset > fsp_size - sizeof(uint32_t))
		return NULL;

	return relative_offset(fsp, offset);
}

static int reloc_type(uint16_t reloc_entry)
{
	/* Reloc type in upper 4 bits */
	return reloc_entry >> 12;
}

static size_t reloc_offset(uint16_t reloc_entry)
{
	/* Offsets are in low 12 bits. */
	return reloc_entry & ((1 << 12) - 1);
}

static int te_relocate(uintptr_t new_addr, void *te)
{
	EFI_TE_IMAGE_HEADER *teih;
	EFI_IMAGE_DATA_DIRECTORY *relocd;
	EFI_IMAGE_BASE_RELOCATION *relocb;
	uintptr_t image_base;
	size_t fixup_offset;
	size_t num_relocs;
	uint16_t *reloc;
	size_t relocd_offset;
	uint8_t *te_base;
	uint32_t adj;

	teih = te;

	if (read_le16(&teih->Signature) != EFI_TE_IMAGE_HEADER_SIGNATURE) {
		printk(BIOS_ERR, "TE Signature mismatch: %x vs %x\n",
			read_le16(&teih->Signature),
			EFI_TE_IMAGE_HEADER_SIGNATURE);
		return -1;
	}

	/*
	 * A TE image is created by converting a PE file. Because of this
	 * the offsets within the headers are off. In order to calculate
	 * the correct relative offsets one needs to subtract fixup_offset
	 * from the encoded offsets. Similarly, the linked address of the
	 * program is found by adding the fixup_offset to the ImageBase.
	 */
	fixup_offset = read_le16(&teih->StrippedSize);
	fixup_offset -= sizeof(EFI_TE_IMAGE_HEADER);
	/* Keep track of a base that is correctly adjusted so that offsets
	 * can be used directly. */
	te_base = te;
	te_base -= fixup_offset;

	image_base = read_le64(&teih->ImageBase);
	adj = new_addr - (image_base + fixup_offset);

	printk(FSP_DBG_LVL, "TE Image %p -> %p adjust value: %x\n",
		(void *)image_base, (void *)new_addr, adj);

	/* Adjust ImageBase for consistency. */
	write_le64(&teih->ImageBase, (uint32_t)(image_base + adj));

	relocd = &teih->DataDirectory[EFI_TE_IMAGE_DIRECTORY_ENTRY_BASERELOC];

	relocd_offset = 0;
	/* Though the field name is VirtualAddress it's actually relative to
	 * the beginning of the image which is linked at ImageBase. */
	relocb = relative_offset(te,
			read_le32(&relocd->VirtualAddress) - fixup_offset);
	while (relocd_offset < read_le32(&relocd->Size)) {
		size_t rva_offset = read_le32(&relocb->VirtualAddress);

		printk(FSP_DBG_LVL, "Relocs for RVA offset %zx\n", rva_offset);
		num_relocs = read_le32(&relocb->SizeOfBlock) - sizeof(*relocb);
		num_relocs /= sizeof(uint16_t);
		reloc = relative_offset(relocb, sizeof(*relocb));

		printk(FSP_DBG_LVL, "Num relocs in block: %zx\n", num_relocs);

		while (num_relocs > 0) {
			uint16_t reloc_val = read_le16(reloc);
			int type = reloc_type(reloc_val);
			size_t offset = reloc_offset(reloc_val);

			printk(FSP_DBG_LVL, "reloc type %x offset %zx\n",
				type, offset);

			if (type == EFI_IMAGE_REL_BASED_HIGHLOW) {
				uint32_t *reloc_addr;
				uint32_t val;

				offset += rva_offset;
				reloc_addr = (void *)&te_base[offset];
				val = read_le32(reloc_addr);

				printk(FSP_DBG_LVL, "Adjusting %p %x -> %x\n",
					reloc_addr, val, val + adj);
				write_le32(reloc_addr, val + adj);
			} else if (type != EFI_IMAGE_REL_BASED_ABSOLUTE) {
				printk(BIOS_ERR, "Unknown reloc type: %x\n",
					type);
				return -1;
			}
			num_relocs--;
			reloc++;
		}

		/* Track consumption of relocation directory contents. */
		relocd_offset += read_le32(&relocb->SizeOfBlock);
		/* Get next relocation block to process. */
		relocb = relative_offset(relocb,
					read_le32(&relocb->SizeOfBlock));
	}

	return 0;
}

static size_t csh_size(const EFI_COMMON_SECTION_HEADER *csh)
{
	size_t size;

	/* Unpack the array into a type that can be used. */
	size = 0;
	size |= read_le8(&csh->Size[0]) << 0;
	size |= read_le8(&csh->Size[1]) << 8;
	size |= read_le8(&csh->Size[2]) << 16;

	return size;
}

static size_t section_data_offset(const EFI_COMMON_SECTION_HEADER *csh)
{
	if (csh_size(csh) == 0x00ffffff)
		return sizeof(EFI_COMMON_SECTION_HEADER2);
	else
		return sizeof(EFI_COMMON_SECTION_HEADER);
}

static size_t section_data_size(const EFI_COMMON_SECTION_HEADER *csh)
{
	size_t section_size;

	if (csh_size(csh) == 0x00ffffff)
		section_size = read_le32(&SECTION2_SIZE(csh));
	else
		section_size = csh_size(csh);

	return section_size - section_data_offset(csh);
}

static size_t file_section_offset(const EFI_FFS_FILE_HEADER *ffsfh)
{
	if (IS_FFS_FILE2(ffsfh))
		return sizeof(EFI_FFS_FILE_HEADER2);
	else
		return sizeof(EFI_FFS_FILE_HEADER);
}

static size_t ffs_file_size(const EFI_FFS_FILE_HEADER *ffsfh)
{
	size_t size;

	if (IS_FFS_FILE2(ffsfh)) {
		/*
		 * this cast is needed with UEFI 2.6 headers in order
		 * to read the UINT32 value that FFS_FILE2_SIZE converts
		 * the return into
		 */
		uint32_t file2_size = FFS_FILE2_SIZE(ffsfh);
		size = read_le32(&file2_size);
	} else {
		size = read_le8(&ffsfh->Size[0]) << 0;
		size |= read_le8(&ffsfh->Size[1]) << 8;
		size |= read_le8(&ffsfh->Size[2]) << 16;
	}
	return size;
}

static int relocate_patch_table(void *fsp, size_t size, size_t offset,
				ssize_t adjustment)
{
	struct fsp_patch_table *table;
	size_t num;
	size_t num_entries;

	table = relative_offset(fsp, offset);

	if ((offset + sizeof(*table) > size) ||
	    (read_le16(&table->header_length) + offset) > size) {
		printk(BIOS_ERR, "FSPP not entirely contained in region.\n");
		return -1;
	}

	num_entries = read_le32(&table->patch_entry_num);
	printk(FSP_DBG_LVL, "FSPP relocs: %zx\n", num_entries);

	for (num = 0; num < num_entries; num++) {
		uint32_t *reloc;
		uint32_t reloc_val;

		reloc = fspp_reloc(fsp, size,
				read_le32(&table->patch_entries[num]));

		if (reloc == NULL) {
			printk(BIOS_ERR, "Ignoring FSPP entry: %x\n",
				read_le32(&table->patch_entries[num]));
			continue;
		}

		reloc_val = read_le32(reloc);
		printk(FSP_DBG_LVL, "Adjusting %p %x -> %x\n",
			reloc, reloc_val,
			(unsigned int)(reloc_val + adjustment));

		write_le32(reloc, reloc_val + adjustment);
	}

	return 0;
}

static ssize_t relocate_remaining_items(void *fsp, size_t size,
					uintptr_t new_addr, size_t fih_offset)
{
	EFI_FFS_FILE_HEADER *ffsfh;
	EFI_COMMON_SECTION_HEADER *csh;
	FSP_INFO_HEADER *fih;
	ssize_t adjustment;
	size_t offset;

	printk(FSP_DBG_LVL, "FSP_INFO_HEADER offset is %zx\n", fih_offset);

	if (fih_offset == 0) {
		printk(BIOS_ERR, "FSP_INFO_HEADER offset is 0.\n");
		return -1;
	}

	/* FSP_INFO_HEADER at first file in FV within first RAW section. */
	ffsfh = relative_offset(fsp, fih_offset);
	fih_offset += file_section_offset(ffsfh);
	csh = relative_offset(fsp, fih_offset);
	fih_offset += section_data_offset(csh);
	fih = relative_offset(fsp, fih_offset);

	if (guid_compare(&ffsfh->Name, &fih_guid)) {
		printk(BIOS_ERR, "Bad FIH GUID.\n");
		return -1;
	}

	if (read_le8(&csh->Type) != EFI_SECTION_RAW) {
		printk(BIOS_ERR, "FIH file should have raw section: %x\n",
			read_le8(&csh->Type));
		return -1;
	}

	if (read_le32(&fih->Signature) != FSP_SIG) {
		printk(BIOS_ERR, "Unexpected FIH signature: %08x\n",
			read_le32(&fih->Signature));
		return -1;
	}

	adjustment = (intptr_t)new_addr - read_le32(&fih->ImageBase);

	/* Update ImageBase to reflect FSP's new home. */
	write_le32(&fih->ImageBase, adjustment + read_le32(&fih->ImageBase));

	/* Need to find patch table and adjust each entry. The tables
	 * following FSP_INFO_HEADER have a 32-bit signature and header
	 * length. The patch table is denoted as having a 'FSPP' signature;
	 * the table format doesn't follow the other tables. */
	offset = fih_offset + read_le32(&fih->HeaderLength);
	while (offset + 2 * sizeof(uint32_t) <= size) {
		uint32_t *table_headers;

		table_headers = relative_offset(fsp, offset);

		printk(FSP_DBG_LVL, "Checking offset %zx for 'FSPP'\n",
			offset);

		if (read_le32(&table_headers[0]) != FSPP_SIG) {
			offset += read_le32(&table_headers[1]);
			continue;
		}

		if (relocate_patch_table(fsp, size, offset, adjustment)) {
			printk(BIOS_ERR, "FSPP relocation failed.\n");
			return -1;
		}

		return fih_offset;
	}

	printk(BIOS_ERR, "Could not find the FSP patch table.\n");
	return -1;
}

static ssize_t relocate_fvh(uintptr_t new_addr, void *fsp, size_t fsp_size,
				size_t fvh_offset, size_t *fih_offset)
{
	EFI_FIRMWARE_VOLUME_HEADER *fvh;
	EFI_FFS_FILE_HEADER *ffsfh;
	EFI_COMMON_SECTION_HEADER *csh;
	size_t offset;
	size_t file_offset;
	size_t size;
	size_t fv_length;

	offset = fvh_offset;
	fvh = relative_offset(fsp, offset);

	if (read_le32(&fvh->Signature) != EFI_FVH_SIGNATURE)
		return -1;

	fv_length = read_le64(&fvh->FvLength);

	printk(FSP_DBG_LVL, "FVH length: %zx Offset: %zx Mapping length: %zx\n",
		fv_length, offset, fsp_size);

	if (fv_length + offset > fsp_size)
		return -1;

	/* Parse only this FV. However, the algorithm uses offsets into the
	 * entire FSP region so make size include the starting offset. */
	size = fv_length + offset;

	if (guid_compare(&fvh->FileSystemGuid, &ffs2_guid)) {
		printk(BIOS_ERR, "FVH not an FFS2 type.\n");
		return -1;
	}

	if (read_le16(&fvh->ExtHeaderOffset) != 0) {
		EFI_FIRMWARE_VOLUME_EXT_HEADER *fveh;

		offset += read_le16(&fvh->ExtHeaderOffset);
		fveh = relative_offset(fsp, offset);
		printk(FSP_DBG_LVL, "Extended Header Offset: %zx Size: %zx\n",
			(size_t)read_le16(&fvh->ExtHeaderOffset),
			(size_t)read_le32(&fveh->ExtHeaderSize));
		offset += read_le32(&fveh->ExtHeaderSize);
		/* FFS files are 8 byte aligned after extended header. */
		offset = ALIGN_UP(offset, 8);
	} else {
		offset += read_le16(&fvh->HeaderLength);
	}

	file_offset = offset;
	while (file_offset + sizeof(*ffsfh) < size) {
		offset = file_offset;
		printk(FSP_DBG_LVL, "file offset: %zx\n", file_offset);

		/* First file and section should be FSP info header. */
		if (fih_offset != NULL && *fih_offset == 0)
			*fih_offset = file_offset;

		ffsfh = relative_offset(fsp, file_offset);

		printk(FSP_DBG_LVL, "file type = %x\n", read_le8(&ffsfh->Type));
		printk(FSP_DBG_LVL, "file attribs = %x\n",
			read_le8(&ffsfh->Attributes));

		/* Exit FV relocation when empty space found */
		if (read_le8(&ffsfh->Type) == EFI_FV_FILETYPE_FFS_MAX)
			break;

		/* Next file on 8 byte alignment. */
		file_offset += ffs_file_size(ffsfh);
		file_offset = ALIGN_UP(file_offset, 8);

		/* Padding files have no section information. */
		if (read_le8(&ffsfh->Type) == EFI_FV_FILETYPE_FFS_PAD)
			continue;

		offset += file_section_offset(ffsfh);

		while (offset + sizeof(*csh) < file_offset) {
			size_t data_size;
			size_t data_offset;

			csh = relative_offset(fsp, offset);

			printk(FSP_DBG_LVL, "section offset: %zx\n", offset);
			printk(FSP_DBG_LVL, "section type: %x\n",
				read_le8(&csh->Type));

			data_size = section_data_size(csh);
			data_offset = section_data_offset(csh);

			if (data_size + data_offset + offset > file_offset) {
				printk(BIOS_ERR, "Section exceeds FV size.\n");
				return -1;
			}

			/*
			 * The entire FSP image can be thought of as one
			 * program with a single link address even though there
			 * are multiple TEs linked separately. The reason is
			 * that each TE is linked for XIP. So in order to
			 * relocate the TE properly we need to form the
			 * relocated address based on the TE offset within
			 * FSP proper.
			 */
			if (read_le8(&csh->Type) == EFI_SECTION_TE) {
				void *te;
				size_t te_offset = offset + data_offset;
				uintptr_t te_addr = new_addr + te_offset;

				printk(FSP_DBG_LVL, "TE image at offset %zx\n",
					te_offset);
				te = relative_offset(fsp, te_offset);
				te_relocate(te_addr, te);
			}

			offset += data_size + data_offset;
			/* Sections are aligned to 4 bytes. */
			offset = ALIGN_UP(offset, 4);
		}
	}

	/* Return amount of buffer parsed: FV size. */
	return fv_length;
}

ssize_t fsp_component_relocate(uintptr_t new_addr, void *fsp, size_t size)
{
	size_t offset;
	size_t fih_offset;

	offset = 0;
	fih_offset = 0;
	while (offset < size) {
		ssize_t nparsed;

		/* Relocate each FV within the FSP region. The FSP_INFO_HEADER
		 * should only be located in the first FV. */
		if (offset == 0)
			nparsed = relocate_fvh(new_addr, fsp, size, offset,
						&fih_offset);
		else
			nparsed = relocate_fvh(new_addr, fsp, size, offset,
						NULL);

		/* FV should be larger than 0 or failed to parse. */
		if (nparsed <= 0) {
			printk(BIOS_ERR, "FV @ offset %zx relocation failed\n",
				offset);
			return -1;
		}

		offset += nparsed;
	}

	return relocate_remaining_items(fsp, size, new_addr, fih_offset);
}

ssize_t fsp1_1_relocate(uintptr_t new_addr, void *fsp, size_t size)
{
	return fsp_component_relocate(new_addr, fsp, size);
}