1 /* Firmware Interface Table support */
2 /* SPDX-License-Identifier: GPL-2.0-only */
12 /* FIXME: This code assumes it is being executed on a little endian machine. */
14 #define FIT_POINTER_LOCATION 0xffffffc0
15 #define FIT_TABLE_LOWEST_ADDRESS ((uint32_t)(-(16 << 20)))
16 #define FIT_ENTRY_CHECKSUM_VALID 0x80
17 #define FIT_HEADER_VERSION 0x0100
18 #define FIT_HEADER_ADDRESS "_FIT_ "
19 #define FIT_MICROCODE_VERSION 0x0100
20 #define FIT_TXT_VERSION 0x0100
22 #define FIT_SIZE_ALIGNMENT 16
26 * Address is the base address of the firmware component
27 * must be aligned on 16 byte boundary
31 * Size is the span of the component in multiple of 16 bytes
32 * Bits [24:31] are reserved and must be set to 0
34 uint32_t size_reserved
;
36 * Component's version number in binary coded decimal (BCD) format.
37 * For the FIT header entry, the value in this field will indicate the
38 * revision number of the FIT data structure. The upper byte of the
39 * revision field indicates the major revision and the lower byte
40 * indicates the minor revision.
44 * FIT types 0x00 to 0x7F
45 * Bit 7 (C_V) indicates whether component has valid checksum.
47 uint8_t type_checksum_valid
;
49 * Component's checksum. The modulo sum of all the bytes in the
50 * component and the value in this field (Chksum) must add up to zero.
51 * This field is only valid if the C_V flag is non-zero.
57 struct fit_entry header
;
58 struct fit_entry entries
[];
61 struct microcode_header
{
65 uint32_t processor_signature
;
67 uint32_t loader_revision
;
68 uint32_t processor_flags
;
74 struct microcode_entry
{
79 static inline void *rom_buffer_pointer(struct buffer
*buffer
, int offset
)
81 return &buffer
->data
[offset
];
84 static inline size_t fit_entry_size_bytes(const struct fit_entry
*entry
)
86 return (entry
->size_reserved
& 0xffffff) << 4;
89 static inline void fit_entry_update_size(struct fit_entry
*entry
,
92 /* Size is multiples of 16 bytes. */
93 entry
->size_reserved
= (size_bytes
>> 4) & 0xffffff;
96 static inline void fit_entry_add_size(struct fit_entry
*entry
,
99 int size
= fit_entry_size_bytes(entry
);
101 fit_entry_update_size(entry
, size
);
104 static inline int fit_entry_type(struct fit_entry
*entry
)
106 return entry
->type_checksum_valid
& ~FIT_ENTRY_CHECKSUM_VALID
;
110 * Get an offset from a host pointer. This function assumes the ROM is located
111 * in the host address space at [4G - romsize -> 4G). It also assume all
112 * pointers have values within this address range.
114 static inline int ptr_to_offset(fit_offset_converter_t helper
,
115 const struct buffer
*region
, uint32_t host_ptr
)
117 return helper(region
, -host_ptr
);
121 * Get a pointer from an offset. This function assumes the ROM is located
122 * in the host address space at [4G - romsize -> 4G). It also assume all
123 * pointers have values within this address range.
125 static inline uint32_t offset_to_ptr(fit_offset_converter_t helper
,
126 const struct buffer
*region
, int offset
)
128 return -helper(region
, offset
);
132 * Return the number of FIT entries.
134 static inline size_t fit_table_entries(const struct fit_table
*fit
)
139 return (fit_entry_size_bytes(&fit
->header
) / FIT_SIZE_ALIGNMENT
) - 1;
143 * Return the number of unused entries.
145 static inline size_t fit_free_space(struct fit_table
*fit
,
146 const size_t max_entries
)
151 return max_entries
- fit_table_entries(fit
);
155 * Sort entries by type and fill gaps (entries with type unused).
156 * To be called after adding or deleting entries.
158 * This one is critical, as mentioned in Chapter 1.2.1 "FIT Ordering Rules"
159 * "Firmware Interface Table BIOS Specification".
161 * We need to use a stable sorting algorithm, as the order of
162 * FIT_TYPE_BIOS_STARTUP matter for measurements.
164 static void sort_fit_table(struct fit_table
*fit
)
166 struct fit_entry tmp
;
170 /* Bubble sort entries */
171 for (j
= 0; j
< fit_table_entries(fit
) - 1; j
++) {
173 for (i
= 0; i
< fit_table_entries(fit
) - j
- 1; i
++) {
174 if (fit
->entries
[i
].type_checksum_valid
<=
175 fit
->entries
[i
+ 1].type_checksum_valid
)
178 memcpy(&tmp
, &fit
->entries
[i
], sizeof(tmp
));
179 memcpy(&fit
->entries
[i
], &fit
->entries
[i
+ 1],
180 sizeof(fit
->entries
[i
]));
181 memcpy(&fit
->entries
[i
+ 1], &tmp
,
182 sizeof(fit
->entries
[i
+ 1]));
190 static int fit_table_verified(struct fit_table
*table
)
195 /* Check that the address field has the proper signature. */
196 if (strncmp((const char *)&table
->header
.address
, FIT_HEADER_ADDRESS
,
197 sizeof(table
->header
.address
)))
200 if (table
->header
.version
!= FIT_HEADER_VERSION
)
203 if (fit_entry_type(&table
->header
) != FIT_TYPE_HEADER
)
206 /* Assume that the FIT table contains at least the header */
207 if (fit_entry_size_bytes(&table
->header
) < sizeof(struct fit_entry
))
214 * Update the FIT checksum.
215 * To be called after modifiying the table.
217 static void update_fit_checksum(struct fit_table
*fit
)
227 fit
->header
.checksum
= 0;
228 size_bytes
= fit_entry_size_bytes(&fit
->header
);
230 buffer
= (void *)fit
;
231 for (i
= 0; i
< size_bytes
; i
++)
233 fit
->header
.checksum
= -result
;
237 * Return a pointer to the next free entry.
238 * Caller must take care if enough space is available.
240 static struct fit_entry
*get_next_free_entry(struct fit_table
*fit
)
242 return &fit
->entries
[fit_table_entries(fit
)];
245 static void fit_location_from_cbfs_header(uint32_t *current_offset
,
246 uint32_t *file_length
, void *ptr
)
249 struct cbfs_file header
;
250 memset(&buf
, 0, sizeof(buf
));
253 buf
.size
= sizeof(header
);
255 bgets(&buf
, header
.magic
, sizeof(header
.magic
));
256 header
.len
= xdr_be
.get32(&buf
);
257 header
.type
= xdr_be
.get32(&buf
);
258 header
.attributes_offset
= xdr_be
.get32(&buf
);
259 header
.offset
= xdr_be
.get32(&buf
);
261 *current_offset
= header
.offset
;
262 *file_length
= header
.len
;
266 parse_microcode_blob(struct cbfs_image
*image
,
267 const char *blob_name
,
269 struct microcode_entry
*mcus
,
270 const size_t max_fit_entries
)
273 uint32_t current_offset
;
274 uint32_t file_length
;
275 struct cbfs_file
*mcode_file
;
277 mcode_file
= cbfs_get_entry(image
, blob_name
);
279 ERROR("Couldn't find microcode blob.\n");
283 fit_location_from_cbfs_header(¤t_offset
, &file_length
,
285 current_offset
+= cbfs_get_entry_addr(image
, mcode_file
);
288 while (file_length
> sizeof(struct microcode_header
)) {
289 const struct microcode_header
*mcu_header
;
291 mcu_header
= rom_buffer_pointer(&image
->buffer
, current_offset
);
293 ERROR("Couldn't parse microcode header.\n");
297 /* Newer microcode updates include a size field, whereas older
298 * containers set it at 0 and are exactly 2048 bytes long */
299 uint32_t total_size
= mcu_header
->total_size
?: 2048;
301 /* Quickly sanity check a prospective microcode update. */
302 if (total_size
< sizeof(*mcu_header
) ||
303 total_size
> file_length
)
306 if (num_mcus
== max_fit_entries
) {
307 ERROR("Maximum of FIT entries reached.\n");
311 /* FIXME: Should the checksum be validated? */
312 mcus
[num_mcus
].offset
= current_offset
;
313 mcus
[num_mcus
].size
= total_size
;
315 /* Proceed to next payload. */
316 current_offset
+= mcus
[num_mcus
].size
;
317 file_length
-= mcus
[num_mcus
].size
;
319 if (file_length
< sizeof(struct microcode_header
))
323 /* Update how many microcode updates we found. */
324 *mcus_found
= num_mcus
;
329 /* There can be zero or more FIT_TYPE_MICROCODE entries */
330 static void update_fit_ucode_entry(struct fit_table
*fit
,
331 struct fit_entry
*entry
,
332 const uint64_t mcu_addr
)
334 entry
->address
= mcu_addr
;
336 * While loading MCU, its size is not referred from FIT and
337 * rather from the MCU header, hence we can assign zero here.
339 entry
->size_reserved
= 0;
340 entry
->type_checksum_valid
= FIT_TYPE_MICROCODE
;
341 entry
->version
= FIT_MICROCODE_VERSION
;
343 fit_entry_add_size(&fit
->header
, sizeof(struct fit_entry
));
347 * There can be zero or one FIT_TYPE_BIOS_ACM entry per table.
348 * In case there's a FIT_TYPE_BIOS_ACM entry, at least one
349 * FIT_TYPE_BIOS_STARTUP entry must exist.
351 * The caller has to provide valid arguments as those aren't verfied.
353 static void update_fit_bios_acm_entry(struct fit_table
*fit
,
354 struct fit_entry
*entry
,
355 const uint64_t acm_addr
)
357 entry
->address
= acm_addr
;
359 * The Address field points to a BIOS ACM. The Address field points to
360 * the first byte of the AC module header. When BIOS ACM is loaded in
361 * Authenticated Code RAM, one MTRR base/limit pair is used to map it.
363 entry
->size_reserved
= 0;
364 entry
->type_checksum_valid
= FIT_TYPE_BIOS_ACM
;
365 entry
->version
= FIT_TXT_VERSION
;
367 fit_entry_add_size(&fit
->header
, sizeof(struct fit_entry
));
371 * In case there's a FIT_TYPE_BIOS_ACM entry, at least one
372 * FIT_TYPE_BIOS_STARTUP entry must exist.
374 * The caller has to provide valid arguments as those aren't verfied.
376 static void update_fit_bios_startup_entry(struct fit_table
*fit
,
377 struct fit_entry
*entry
,
378 const uint64_t sm_addr
,
379 const uint32_t sm_size
)
381 entry
->address
= sm_addr
;
382 assert(sm_size
% 16 == 0);
384 * BIOS Startup code is defined as the code that gets control at the
385 * reset vector and continues the chain of trust in TCG-compliant
386 * fashion. In addition, this code may also configure memory and SMRAM.
388 fit_entry_update_size(entry
, sm_size
);
389 entry
->type_checksum_valid
= FIT_TYPE_BIOS_STARTUP
;
390 entry
->version
= FIT_TXT_VERSION
;
392 fit_entry_add_size(&fit
->header
, sizeof(struct fit_entry
));
396 * There can be zero or one FIT_TYPE_BIOS_POLICY Record in the FIT.
397 * If the platform uses the hash comparison method and employs a
398 * failsafe bootblock, one FIT_TYPE_BIOS_POLICY entry is needed to
399 * contain the failsafe hash.
400 * If the platform uses the Signature verification method, one
401 * FIT_TYPE_BIOS_POLICY entry is needed. In this case, the entry
402 * contains the OEM key, hash of the BIOS and signature over the hash
404 * In all other cases, the FIT_TYPE_BIOS_POLICY record is not required.
406 * The caller has to provide valid arguments as those aren't verfied.
408 static void update_fit_bios_policy_entry(struct fit_table
*fit
,
409 struct fit_entry
*entry
,
410 const uint64_t lcp_policy_addr
,
411 const uint32_t lcp_policy_size
)
413 entry
->address
= lcp_policy_addr
;
414 fit_entry_update_size(entry
, lcp_policy_size
);
415 entry
->type_checksum_valid
= FIT_TYPE_BIOS_POLICY
;
416 entry
->version
= FIT_TXT_VERSION
;
418 fit_entry_add_size(&fit
->header
, sizeof(struct fit_entry
));
422 * There can be zero or one FIT_TYPE_TXT_POLICY entries
424 * The caller has to provide valid arguments as those aren't verfied.
426 static void update_fit_txt_policy_entry(struct fit_table
*fit
,
427 struct fit_entry
*entry
,
428 uint64_t txt_policy_addr
)
430 entry
->address
= txt_policy_addr
;
432 * Points to the flag indicating if TXT is enabled on this platform.
433 * If not present, TXT is not disabled by FIT.
435 entry
->size_reserved
= 0;
436 entry
->type_checksum_valid
= FIT_TYPE_TXT_POLICY
;
437 entry
->version
= 0x1;
439 fit_entry_add_size(&fit
->header
, sizeof(struct fit_entry
));
443 * There can be zero or one FIT_TYPE_BOOT_POLICY entries
445 * The caller has to provide valid arguments as those aren't verified.
447 static void update_fit_boot_policy_entry(struct fit_table
*fit
,
448 struct fit_entry
*entry
,
449 uint64_t boot_policy_addr
,
450 uint32_t boot_policy_size
)
452 entry
->address
= boot_policy_addr
;
453 entry
->type_checksum_valid
= FIT_TYPE_BOOT_POLICY
;
454 entry
->size_reserved
= boot_policy_size
;
455 entry
->version
= FIT_TXT_VERSION
;
457 fit_entry_add_size(&fit
->header
, sizeof(struct fit_entry
));
461 * There can be zero or one FIT_TYPE_KEY_MANIFEST entries
463 * The caller has to provide valid arguments as those aren't verified.
465 static void update_fit_key_manifest_entry(struct fit_table
*fit
,
466 struct fit_entry
*entry
,
467 uint64_t key_manifest_addr
,
468 uint32_t key_manifest_size
)
470 entry
->address
= key_manifest_addr
;
472 entry
->type_checksum_valid
= FIT_TYPE_KEY_MANIFEST
;
473 entry
->size_reserved
= key_manifest_size
;
474 entry
->version
= FIT_TXT_VERSION
;
476 fit_entry_add_size(&fit
->header
, sizeof(struct fit_entry
));
479 /* Special case for ucode CBFS file, as it might contain more than one ucode */
480 int fit_add_microcode_file(struct fit_table
*fit
,
481 struct cbfs_image
*image
,
482 const char *blob_name
,
483 fit_offset_converter_t offset_helper
,
484 const size_t max_fit_entries
)
486 struct microcode_entry
*mcus
;
491 mcus
= malloc(sizeof(*mcus
) * max_fit_entries
);
493 ERROR("Couldn't allocate memory for microcode entries.\n");
497 if (parse_microcode_blob(image
, blob_name
, &mcus_found
, mcus
,
503 for (i
= 0; i
< mcus_found
; i
++) {
504 if (fit_add_entry(fit
,
505 offset_to_ptr(offset_helper
, &image
->buffer
,
520 static uint32_t *get_fit_ptr(struct buffer
*bootblock
, fit_offset_converter_t offset_fn
,
521 uint32_t topswap_size
)
523 return rom_buffer_pointer(bootblock
,
524 ptr_to_offset(offset_fn
, bootblock
,
525 FIT_POINTER_LOCATION
- topswap_size
));
528 /* Set the FIT pointer to a FIT table. */
529 int set_fit_pointer(struct buffer
*bootblock
,
530 const uint32_t fit_address
,
531 fit_offset_converter_t offset_fn
,
532 uint32_t topswap_size
)
534 struct fit_table
*fit
;
535 uint32_t *fit_pointer
= get_fit_ptr(bootblock
, offset_fn
, topswap_size
);
537 fit
= rom_buffer_pointer(bootblock
, ptr_to_offset(offset_fn
, bootblock
, fit_address
));
539 if (fit_address
< FIT_TABLE_LOWEST_ADDRESS
) {
540 ERROR("FIT must be reside in the top 16MiB.\n");
544 if (!fit_table_verified(fit
)) {
545 ERROR("FIT not found at address.\n");
549 fit_pointer
[0] = fit_address
;
555 * Return a pointer to the active FIT.
557 struct fit_table
*fit_get_table(struct buffer
*bootblock
,
558 fit_offset_converter_t offset_fn
,
559 uint32_t topswap_size
)
561 struct fit_table
*fit
;
562 uint32_t *fit_pointer
= get_fit_ptr(bootblock
, offset_fn
, topswap_size
);
564 /* Ensure pointer is below 4GiB and within 16MiB of 4GiB */
565 if (fit_pointer
[1] != 0 || fit_pointer
[0] < FIT_TABLE_LOWEST_ADDRESS
) {
566 ERROR("FIT not found.\n");
570 fit
= rom_buffer_pointer(bootblock
,
571 ptr_to_offset(offset_fn
, bootblock
, *fit_pointer
));
572 if (!fit_table_verified(fit
)) {
573 ERROR("FIT not found.\n");
581 * Dump the current FIT in human readable format to stdout.
583 int fit_dump(struct fit_table
*fit
)
591 printf(" FIT table:\n");
593 if (fit_table_entries(fit
) < 1) {
594 printf(" empty\n\n");
598 printf(" %-6s %-20s %-16s %-8s\n", "Index", "Type", "Addr", "Size");
600 for (i
= 0; i
< fit_table_entries(fit
); i
++) {
603 switch (fit
->entries
[i
].type_checksum_valid
) {
604 case FIT_TYPE_MICROCODE
:
607 case FIT_TYPE_BIOS_ACM
:
610 case FIT_TYPE_BIOS_STARTUP
:
611 name
= "BIOS Startup Module";
613 case FIT_TYPE_TPM_POLICY
:
616 case FIT_TYPE_BIOS_POLICY
:
617 name
= "BIOS Policy";
619 case FIT_TYPE_TXT_POLICY
:
622 case FIT_TYPE_KEY_MANIFEST
:
623 name
= "Key Manifest";
625 case FIT_TYPE_BOOT_POLICY
:
626 name
= "Boot Policy";
628 case FIT_TYPE_CSE_SECURE_BOOT
:
629 name
= "CSE SecureBoot";
631 case FIT_TYPE_TXTSX_POLICY
:
632 name
= "TXTSX policy";
634 case FIT_TYPE_JMP_DEBUG_POLICY
:
635 name
= "JMP debug policy";
637 case FIT_TYPE_UNUSED
:
644 printf(" %6zd %-20s 0x%08"PRIx64
" 0x%08zx\n", i
, name
,
645 fit
->entries
[i
].address
,
646 fit_entry_size_bytes(&fit
->entries
[i
]));
653 * Remove all entries from table.
655 int fit_clear_table(struct fit_table
*fit
)
660 memset(fit
->entries
, 0,
661 sizeof(struct fit_entry
) * fit_table_entries(fit
));
663 /* Reset entry counter in header */
664 fit_entry_update_size(&fit
->header
, sizeof(fit
->header
));
666 update_fit_checksum(fit
);
672 * Returns true if the FIT type is know and can be added to the table.
674 int fit_is_supported_type(const enum fit_type type
)
677 case FIT_TYPE_MICROCODE
:
678 case FIT_TYPE_BIOS_ACM
:
679 case FIT_TYPE_BIOS_STARTUP
:
680 case FIT_TYPE_BIOS_POLICY
:
681 case FIT_TYPE_TXT_POLICY
:
682 case FIT_TYPE_KEY_MANIFEST
:
683 case FIT_TYPE_BOOT_POLICY
:
685 case FIT_TYPE_TPM_POLICY
:
692 * Adds an known entry to the FIT.
693 * len is optional for same types and might be zero.
694 * offset is an absolute address in 32-bit protected mode address space.
696 int fit_add_entry(struct fit_table
*fit
,
697 const uint32_t offset
,
699 const enum fit_type type
,
700 const size_t max_fit_entries
)
702 struct fit_entry
*entry
;
705 ERROR("Internal error.");
709 if (fit_free_space(fit
, max_fit_entries
) < 1) {
710 ERROR("No space left in FIT.");
714 if (!fit_is_supported_type(type
)) {
715 ERROR("Unsupported FIT type %u\n", type
);
719 DEBUG("Adding new entry type %u at offset %zd\n", type
,
720 fit_table_entries(fit
));
722 entry
= get_next_free_entry(fit
);
725 case FIT_TYPE_MICROCODE
:
726 update_fit_ucode_entry(fit
, entry
, offset
);
728 case FIT_TYPE_BIOS_ACM
:
729 update_fit_bios_acm_entry(fit
, entry
, offset
);
731 case FIT_TYPE_BIOS_STARTUP
:
732 update_fit_bios_startup_entry(fit
, entry
, offset
, len
);
734 case FIT_TYPE_BIOS_POLICY
:
735 update_fit_bios_policy_entry(fit
, entry
, offset
, len
);
737 case FIT_TYPE_TXT_POLICY
:
738 update_fit_txt_policy_entry(fit
, entry
, offset
);
740 case FIT_TYPE_KEY_MANIFEST
:
741 update_fit_key_manifest_entry(fit
, entry
, offset
, len
);
743 case FIT_TYPE_BOOT_POLICY
:
744 update_fit_boot_policy_entry(fit
, entry
, offset
, len
);
752 update_fit_checksum(fit
);
758 * Delete one entry from table.
760 int fit_delete_entry(struct fit_table
*fit
,
764 ERROR("Internal error.");
768 if (idx
>= fit_table_entries(fit
)) {
769 ERROR("Index out of range.");
773 memset(&fit
->entries
[idx
], 0, sizeof(struct fit_entry
));
775 fit
->entries
[idx
].type_checksum_valid
= FIT_TYPE_UNUSED
;
779 /* The unused entry is now the last one */
780 fit_entry_add_size(&fit
->header
, -(int)sizeof(struct fit_entry
));
782 update_fit_checksum(fit
);