1 /*
2 * SPDX-License-Identifier: Apache-2.0
3 *
4 * Copyright (c) 2017-2020 Linaro LTD
5 * Copyright (c) 2017-2019 JUUL Labs
6 * Copyright (c) 2019-2021 Arm Limited
7 *
8 * Original license:
9 *
10 * Licensed to the Apache Software Foundation (ASF) under one
11 * or more contributor license agreements. See the NOTICE file
12 * distributed with this work for additional information
13 * regarding copyright ownership. The ASF licenses this file
14 * to you under the Apache License, Version 2.0 (the
15 * "License"); you may not use this file except in compliance
16 * with the License. You may obtain a copy of the License at
17 *
18 * http://www.apache.org/licenses/LICENSE-2.0
19 *
20 * Unless required by applicable law or agreed to in writing,
21 * software distributed under the License is distributed on an
22 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
23 * KIND, either express or implied. See the License for the
24 * specific language governing permissions and limitations
25 * under the License.
26 */
27
28 #ifndef H_BOOTUTIL_PRIV_
29 #define H_BOOTUTIL_PRIV_
30
31 #include <string.h>
32
33 #include "sysflash/sysflash.h"
34
35 #include <flash_map_backend/flash_map_backend.h>
36
37 #include "bootutil/bootutil.h"
38 #include "bootutil/image.h"
39 #include "bootutil/fault_injection_hardening.h"
40 #include "mcuboot_config/mcuboot_config.h"
41
42 #ifdef MCUBOOT_ENC_IMAGES
43 #include "bootutil/enc_key.h"
44 #endif
45
46 #ifdef __cplusplus
47 extern "C" {
48 #endif
49
50 struct flash_area;
51
52 #define BOOT_TMPBUF_SZ 256
53
54 /** Number of image slots in flash; currently limited to two. */
55 #define BOOT_NUM_SLOTS 2
56
57 #if (defined(MCUBOOT_OVERWRITE_ONLY) + \
58 defined(MCUBOOT_SWAP_USING_MOVE) + \
59 defined(MCUBOOT_DIRECT_XIP) + \
60 defined(MCUBOOT_RAM_LOAD)) > 1
61 #error "Please enable only one of MCUBOOT_OVERWRITE_ONLY, MCUBOOT_SWAP_USING_MOVE, MCUBOOT_DIRECT_XIP or MCUBOOT_RAM_LOAD"
62 #endif
63
64 #if !defined(MCUBOOT_OVERWRITE_ONLY) && \
65 !defined(MCUBOOT_SWAP_USING_MOVE) && \
66 !defined(MCUBOOT_DIRECT_XIP) && \
67 !defined(MCUBOOT_RAM_LOAD) && \
68 !defined(MCUBOOT_SINGLE_APPLICATION_SLOT)
69 #define MCUBOOT_SWAP_USING_SCRATCH 1
70 #endif
71
72 #define BOOT_STATUS_OP_MOVE 1
73 #define BOOT_STATUS_OP_SWAP 2
74
75 /*
76 * Maintain state of copy progress.
77 */
78 struct boot_status {
79 uint32_t idx; /* Which area we're operating on */
80 uint8_t state; /* Which part of the swapping process are we at */
81 uint8_t op; /* What operation are we performing? */
82 uint8_t use_scratch; /* Are status bytes ever written to scratch? */
83 uint8_t swap_type; /* The type of swap in effect */
84 uint32_t swap_size; /* Total size of swapped image */
85 #ifdef MCUBOOT_ENC_IMAGES
86 uint8_t enckey[BOOT_NUM_SLOTS][BOOT_ENC_KEY_ALIGN_SIZE];
87 #if MCUBOOT_SWAP_SAVE_ENCTLV
88 uint8_t enctlv[BOOT_NUM_SLOTS][BOOT_ENC_TLV_ALIGN_SIZE];
89 #endif
90 #endif
91 int source; /* Which slot contains swap status metadata */
92 };
93
94 #define BOOT_STATUS_IDX_0 1
95
96 #define BOOT_STATUS_STATE_0 1
97 #define BOOT_STATUS_STATE_1 2
98 #define BOOT_STATUS_STATE_2 3
99
100 /**
101 * End-of-image slot structure.
102 *
103 * 0 1 2 3
104 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
105 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
106 * ~ ~
107 * ~ Swap status (BOOT_MAX_IMG_SECTORS * min-write-size * 3) ~
108 * ~ ~
109 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
110 * | Encryption key 0 (16 octets) [*] |
111 * | |
112 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
113 * | 0xff padding as needed |
114 * | (BOOT_MAX_ALIGN minus 16 octets from Encryption key 0) [*] |
115 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
116 * | Encryption key 1 (16 octets) [*] |
117 * | |
118 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
119 * | 0xff padding as needed |
120 * | (BOOT_MAX_ALIGN minus 16 octets from Encryption key 1) [*] |
121 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
122 * | Swap size (4 octets) |
123 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
124 * | 0xff padding as needed |
125 * | (BOOT_MAX_ALIGN minus 4 octets from Swap size) |
126 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
127 * | Swap info | 0xff padding (BOOT_MAX_ALIGN minus 1 octet) |
128 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
129 * | Copy done | 0xff padding (BOOT_MAX_ALIGN minus 1 octet) |
130 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
131 * | Image OK | 0xff padding (BOOT_MAX_ALIGN minus 1 octet) |
132 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
133 * | 0xff padding as needed |
134 * | (BOOT_MAX_ALIGN minus 16 octets from MAGIC) |
135 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
136 * | MAGIC (16 octets) |
137 * | |
138 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
139 *
140 * [*]: Only present if the encryption option is enabled
141 * (`MCUBOOT_ENC_IMAGES`).
142 */
143
144 union boot_img_magic_t
145 {
146 struct {
147 uint16_t align;
148 uint8_t magic[14];
149 };
150 uint8_t val[16];
151 };
152
153 extern const union boot_img_magic_t boot_img_magic;
154
155 #define BOOT_IMG_MAGIC (boot_img_magic.val)
156
157 #if BOOT_MAX_ALIGN == 8
158 #define BOOT_IMG_ALIGN (BOOT_MAX_ALIGN)
159 #else
160 #define BOOT_IMG_ALIGN (boot_img_magic.align)
161 #endif
162
163 _Static_assert(sizeof(boot_img_magic) == BOOT_MAGIC_SZ, "Invalid size for image magic");
164
165 #if !defined(MCUBOOT_DIRECT_XIP) && !defined(MCUBOOT_RAM_LOAD)
166 #define ARE_SLOTS_EQUIVALENT() 0
167 #else
168 #define ARE_SLOTS_EQUIVALENT() 1
169
170 #if defined(MCUBOOT_DIRECT_XIP) && defined(MCUBOOT_ENC_IMAGES)
171 #error "Image encryption (MCUBOOT_ENC_IMAGES) is not supported when MCUBOOT_DIRECT_XIP is selected."
172 #endif /* MCUBOOT_DIRECT_XIP && MCUBOOT_ENC_IMAGES */
173 #endif /* MCUBOOT_DIRECT_XIP || MCUBOOT_RAM_LOAD */
174
175 #define BOOT_MAX_IMG_SECTORS MCUBOOT_MAX_IMG_SECTORS
176
177 #define BOOT_LOG_IMAGE_INFO(slot, hdr) \
178 BOOT_LOG_INF("%-9s slot: version=%u.%u.%u+%u", \
179 ((slot) == BOOT_PRIMARY_SLOT) ? "Primary" : "Secondary", \
180 (hdr)->ih_ver.iv_major, \
181 (hdr)->ih_ver.iv_minor, \
182 (hdr)->ih_ver.iv_revision, \
183 (hdr)->ih_ver.iv_build_num)
184
185 #if MCUBOOT_SWAP_USING_MOVE
186 #define BOOT_STATUS_MOVE_STATE_COUNT 1
187 #define BOOT_STATUS_SWAP_STATE_COUNT 2
188 #define BOOT_STATUS_STATE_COUNT (BOOT_STATUS_MOVE_STATE_COUNT + BOOT_STATUS_SWAP_STATE_COUNT)
189 #else
190 #define BOOT_STATUS_STATE_COUNT 3
191 #endif
192
193 /** Maximum number of image sectors supported by the bootloader. */
194 #define BOOT_STATUS_MAX_ENTRIES BOOT_MAX_IMG_SECTORS
195
196 #define BOOT_PRIMARY_SLOT 0
197 #define BOOT_SECONDARY_SLOT 1
198
199 #define BOOT_STATUS_SOURCE_NONE 0
200 #define BOOT_STATUS_SOURCE_SCRATCH 1
201 #define BOOT_STATUS_SOURCE_PRIMARY_SLOT 2
202
203 /**
204 * Compatibility shim for flash sector type.
205 *
206 * This can be deleted when flash_area_to_sectors() is removed.
207 */
208 #ifdef MCUBOOT_USE_FLASH_AREA_GET_SECTORS
209 typedef struct flash_sector boot_sector_t;
210 #else
211 typedef struct flash_area boot_sector_t;
212 #endif
213
214 /** Private state maintained during boot. */
215 struct boot_loader_state {
216 struct {
217 struct image_header hdr;
218 const struct flash_area *area;
219 boot_sector_t *sectors;
220 uint32_t num_sectors;
221 } imgs[BOOT_IMAGE_NUMBER][BOOT_NUM_SLOTS];
222
223 #if MCUBOOT_SWAP_USING_SCRATCH
224 struct {
225 const struct flash_area *area;
226 boot_sector_t *sectors;
227 uint32_t num_sectors;
228 } scratch;
229 #endif
230
231 uint8_t swap_type[BOOT_IMAGE_NUMBER];
232 uint32_t write_sz;
233
234 #if defined(MCUBOOT_ENC_IMAGES)
235 struct enc_key_data enc[BOOT_IMAGE_NUMBER][BOOT_NUM_SLOTS];
236 #endif
237
238 #if (BOOT_IMAGE_NUMBER > 1)
239 uint8_t curr_img_idx;
240 bool img_mask[BOOT_IMAGE_NUMBER];
241 #endif
242
243 #if defined(MCUBOOT_DIRECT_XIP) || defined(MCUBOOT_RAM_LOAD)
244 struct slot_usage_t {
245 /* Index of the slot chosen to be loaded */
246 uint32_t active_slot;
247 bool slot_available[BOOT_NUM_SLOTS];
248 #if defined(MCUBOOT_RAM_LOAD)
249 /* Image destination and size for the active slot */
250 uint32_t img_dst;
251 uint32_t img_sz;
252 #elif defined(MCUBOOT_DIRECT_XIP_REVERT)
253 /* Swap status for the active slot */
254 struct boot_swap_state swap_state;
255 #endif
256 } slot_usage[BOOT_IMAGE_NUMBER];
257 #endif /* MCUBOOT_DIRECT_XIP || MCUBOOT_RAM_LOAD */
258 };
259
260 fih_ret bootutil_verify_sig(uint8_t *hash, uint32_t hlen, uint8_t *sig,
261 size_t slen, uint8_t key_id);
262
263 fih_ret boot_fih_memequal(const void *s1, const void *s2, size_t n);
264
265 int boot_find_status(int image_index, const struct flash_area **fap);
266 int boot_magic_compatible_check(uint8_t tbl_val, uint8_t val);
267 uint32_t boot_status_sz(uint32_t min_write_sz);
268 uint32_t boot_trailer_sz(uint32_t min_write_sz);
269 int boot_status_entries(int image_index, const struct flash_area *fap);
270 uint32_t boot_status_off(const struct flash_area *fap);
271 int boot_read_swap_state(const struct flash_area *fap,
272 struct boot_swap_state *state);
273 int boot_read_swap_state_by_id(int flash_area_id,
274 struct boot_swap_state *state);
275 int boot_write_magic(const struct flash_area *fap);
276 int boot_write_status(const struct boot_loader_state *state, struct boot_status *bs);
277 int boot_write_copy_done(const struct flash_area *fap);
278 int boot_write_image_ok(const struct flash_area *fap);
279 int boot_write_swap_info(const struct flash_area *fap, uint8_t swap_type,
280 uint8_t image_num);
281 int boot_write_swap_size(const struct flash_area *fap, uint32_t swap_size);
282 int boot_write_trailer(const struct flash_area *fap, uint32_t off,
283 const uint8_t *inbuf, uint8_t inlen);
284 int boot_write_trailer_flag(const struct flash_area *fap, uint32_t off,
285 uint8_t flag_val);
286 int boot_read_swap_size(const struct flash_area *fap, uint32_t *swap_size);
287 int boot_slots_compatible(struct boot_loader_state *state);
288 uint32_t boot_status_internal_off(const struct boot_status *bs, int elem_sz);
289 int boot_read_image_header(struct boot_loader_state *state, int slot,
290 struct image_header *out_hdr, struct boot_status *bs);
291 int boot_copy_region(struct boot_loader_state *state,
292 const struct flash_area *fap_src,
293 const struct flash_area *fap_dst,
294 uint32_t off_src, uint32_t off_dst, uint32_t sz);
295 int boot_erase_region(const struct flash_area *fap, uint32_t off, uint32_t sz);
296 bool boot_status_is_reset(const struct boot_status *bs);
297
298 #ifdef MCUBOOT_ENC_IMAGES
299 int boot_write_enc_key(const struct flash_area *fap, uint8_t slot,
300 const struct boot_status *bs);
301 int boot_read_enc_key(const struct flash_area *fap, uint8_t slot,
302 struct boot_status *bs);
303 #endif
304
305 /**
306 * Checks that a buffer is erased according to what the erase value for the
307 * flash device provided in `flash_area` is.
308 *
309 * @returns true if the buffer is erased; false if any of the bytes is not
310 * erased, or when buffer is NULL, or when len == 0.
311 */
312 bool bootutil_buffer_is_erased(const struct flash_area *area,
313 const void *buffer, size_t len);
314
315 /**
316 * Safe (non-overflowing) uint32_t addition. Returns true, and stores
317 * the result in *dest if it can be done without overflow. Otherwise,
318 * returns false.
319 */
boot_u32_safe_add(uint32_t * dest,uint32_t a,uint32_t b)320 static inline bool boot_u32_safe_add(uint32_t *dest, uint32_t a, uint32_t b)
321 {
322 /*
323 * "a + b <= UINT32_MAX", subtract 'b' from both sides to avoid
324 * the overflow.
325 */
326 if (a > UINT32_MAX - b) {
327 return false;
328 } else {
329 *dest = a + b;
330 return true;
331 }
332 }
333
334 /**
335 * Safe (non-overflowing) uint16_t addition. Returns true, and stores
336 * the result in *dest if it can be done without overflow. Otherwise,
337 * returns false.
338 */
boot_u16_safe_add(uint16_t * dest,uint16_t a,uint16_t b)339 static inline bool boot_u16_safe_add(uint16_t *dest, uint16_t a, uint16_t b)
340 {
341 uint32_t tmp = a + b;
342 if (tmp > UINT16_MAX) {
343 return false;
344 } else {
345 *dest = tmp;
346 return true;
347 }
348 }
349
350 /*
351 * Accessors for the contents of struct boot_loader_state.
352 */
353
354 /* These are macros so they can be used as lvalues. */
355 #if (BOOT_IMAGE_NUMBER > 1)
356 #define BOOT_CURR_IMG(state) ((state)->curr_img_idx)
357 #else
358 #define BOOT_CURR_IMG(state) 0
359 #endif
360 #ifdef MCUBOOT_ENC_IMAGES
361 #define BOOT_CURR_ENC(state) ((state)->enc[BOOT_CURR_IMG(state)])
362 #else
363 #define BOOT_CURR_ENC(state) NULL
364 #endif
365 #define BOOT_IMG(state, slot) ((state)->imgs[BOOT_CURR_IMG(state)][(slot)])
366 #define BOOT_IMG_AREA(state, slot) (BOOT_IMG(state, slot).area)
367 #define BOOT_WRITE_SZ(state) ((state)->write_sz)
368 #define BOOT_SWAP_TYPE(state) ((state)->swap_type[BOOT_CURR_IMG(state)])
369 #define BOOT_TLV_OFF(hdr) ((hdr)->ih_hdr_size + (hdr)->ih_img_size)
370
371 #define BOOT_IS_UPGRADE(swap_type) \
372 (((swap_type) == BOOT_SWAP_TYPE_TEST) || \
373 ((swap_type) == BOOT_SWAP_TYPE_REVERT) || \
374 ((swap_type) == BOOT_SWAP_TYPE_PERM))
375
376 static inline struct image_header*
boot_img_hdr(struct boot_loader_state * state,size_t slot)377 boot_img_hdr(struct boot_loader_state *state, size_t slot)
378 {
379 return &BOOT_IMG(state, slot).hdr;
380 }
381
382 static inline size_t
boot_img_num_sectors(const struct boot_loader_state * state,size_t slot)383 boot_img_num_sectors(const struct boot_loader_state *state, size_t slot)
384 {
385 return BOOT_IMG(state, slot).num_sectors;
386 }
387
388 /*
389 * Offset of the slot from the beginning of the flash device.
390 */
391 static inline uint32_t
boot_img_slot_off(struct boot_loader_state * state,size_t slot)392 boot_img_slot_off(struct boot_loader_state *state, size_t slot)
393 {
394 return flash_area_get_off(BOOT_IMG(state, slot).area);
395 }
396
397 #ifndef MCUBOOT_USE_FLASH_AREA_GET_SECTORS
398
399 static inline size_t
boot_img_sector_size(const struct boot_loader_state * state,size_t slot,size_t sector)400 boot_img_sector_size(const struct boot_loader_state *state,
401 size_t slot, size_t sector)
402 {
403 return flash_area_get_size(&BOOT_IMG(state, slot).sectors[sector]);
404 }
405
406 /*
407 * Offset of the sector from the beginning of the image, NOT the flash
408 * device.
409 */
410 static inline uint32_t
boot_img_sector_off(const struct boot_loader_state * state,size_t slot,size_t sector)411 boot_img_sector_off(const struct boot_loader_state *state, size_t slot,
412 size_t sector)
413 {
414 return flash_area_get_off(&BOOT_IMG(state, slot).sectors[sector]) -
415 flash_area_get_off(&BOOT_IMG(state, slot).sectors[0]);
416 }
417
418 #else /* defined(MCUBOOT_USE_FLASH_AREA_GET_SECTORS) */
419
420 static inline size_t
boot_img_sector_size(const struct boot_loader_state * state,size_t slot,size_t sector)421 boot_img_sector_size(const struct boot_loader_state *state,
422 size_t slot, size_t sector)
423 {
424 return flash_sector_get_size(&BOOT_IMG(state, slot).sectors[sector]);
425 }
426
427 static inline uint32_t
boot_img_sector_off(const struct boot_loader_state * state,size_t slot,size_t sector)428 boot_img_sector_off(const struct boot_loader_state *state, size_t slot,
429 size_t sector)
430 {
431 return flash_sector_get_off(&BOOT_IMG(state, slot).sectors[sector]) -
432 flash_sector_get_off(&BOOT_IMG(state, slot).sectors[0]);
433 }
434
435 #endif /* !defined(MCUBOOT_USE_FLASH_AREA_GET_SECTORS) */
436
437 #ifdef MCUBOOT_RAM_LOAD
438 # ifdef __BOOTSIM__
439
440 /* Query for the layout of a RAM buffer appropriate for holding the
441 * image. This will be per-test-thread, and therefore must be queried
442 * through this call. */
443 struct bootsim_ram_info {
444 uint32_t start;
445 uint32_t size;
446 uintptr_t base;
447 };
448 struct bootsim_ram_info *bootsim_get_ram_info(void);
449
450 #define IMAGE_GET_FIELD(field) (bootsim_get_ram_info()->field)
451 #define IMAGE_RAM_BASE IMAGE_GET_FIELD(base)
452 #define IMAGE_EXECUTABLE_RAM_START IMAGE_GET_FIELD(start)
453 #define IMAGE_EXECUTABLE_RAM_SIZE IMAGE_GET_FIELD(size)
454
455 # else
456 # define IMAGE_RAM_BASE ((uintptr_t)0)
457 # endif
458
459 #define LOAD_IMAGE_DATA(hdr, fap, start, output, size) \
460 (memcpy((output),(void*)(IMAGE_RAM_BASE + (hdr)->ih_load_addr + (start)), \
461 (size)), 0)
462 #else
463 #define IMAGE_RAM_BASE ((uintptr_t)0)
464
465 #define LOAD_IMAGE_DATA(hdr, fap, start, output, size) \
466 (flash_area_read((fap), (start), (output), (size)))
467 #endif /* MCUBOOT_RAM_LOAD */
468
469 uint32_t bootutil_max_image_size(const struct flash_area *fap);
470
471 #ifdef __cplusplus
472 }
473 #endif
474
475 #endif
476
