/ util / cbfstool / cbfs_image.c
cbfs_image.c
   1  /* CBFS Image Manipulation */
   2  /* SPDX-License-Identifier: GPL-2.0-only */
   3  
   4  #include <inttypes.h>
   5  #include <libgen.h>
   6  #include <stddef.h>
   7  #include <stdio.h>
   8  #include <stdlib.h>
   9  #include <string.h>
  10  #include <strings.h>
  11  #include <commonlib/endian.h>
  12  #include <vb2_sha.h>
  13  
  14  #include "common.h"
  15  #include "cbfs_image.h"
  16  #include "elfparsing.h"
  17  #include "rmodule.h"
  18  
  19  /* Even though the file-adding functions---cbfs_add_entry() and
  20   * cbfs_add_entry_at()---perform their sizing checks against the beginning of
  21   * the subsequent section rather than a stable recorded value such as an empty
  22   * file header's len field, it's possible to prove two interesting properties
  23   * about their behavior:
  24   *  - Placing a new file within an empty entry located below an existing file
  25   *    entry will never leave an aligned flash address containing neither the
  26   *    beginning of a file header nor part of a file.
  27   *  - Placing a new file in an empty entry at the very end of the image such
  28   *    that it fits, but leaves no room for a final header, is guaranteed not to
  29   *    change the total amount of space for entries, even if that new file is
  30   *    later removed from the CBFS.
  31   * These properties are somewhat nonobvious from the implementation, so the
  32   * reader is encouraged to blame this comment and examine the full proofs
  33   * in the commit message before making significant changes that would risk
  34   * removing said guarantees.
  35   */
  36  
  37  static const char *lookup_name_by_type(const struct typedesc_t *desc, uint32_t type,
  38  				const char *default_value)
  39  {
  40  	int i;
  41  	for (i = 0; desc[i].name; i++)
  42  		if (desc[i].type == type)
  43  			return desc[i].name;
  44  	return default_value;
  45  }
  46  
  47  static int lookup_type_by_name(const struct typedesc_t *desc, const char *name)
  48  {
  49  	int i;
  50  	for (i = 0; desc[i].name && strcasecmp(name, desc[i].name); ++i);
  51  	return desc[i].name ? (int)desc[i].type : -1;
  52  }
  53  
  54  static const char *get_cbfs_entry_type_name(uint32_t type)
  55  {
  56  	return lookup_name_by_type(filetypes, type, "(unknown)");
  57  }
  58  
  59  int cbfs_parse_comp_algo(const char *name)
  60  {
  61  	return lookup_type_by_name(types_cbfs_compression, name);
  62  }
  63  
  64  /* CBFS image */
  65  
  66  size_t cbfs_calculate_file_header_size(const char *name)
  67  {
  68  	return (sizeof(struct cbfs_file) +
  69  		align_up(strlen(name) + 1, CBFS_ATTRIBUTE_ALIGN));
  70  }
  71  
  72  /* Only call on legacy CBFSes possessing a master header. */
  73  static int cbfs_fix_legacy_size(struct cbfs_image *image, char *hdr_loc)
  74  {
  75  	assert(image);
  76  	assert(cbfs_is_legacy_cbfs(image));
  77  	// A bug in old cbfstool may produce extra few bytes (by alignment) and
  78  	// cause cbfstool to overwrite things after free space -- which is
  79  	// usually CBFS header on x86. We need to workaround that.
  80  	// Except when we run across a file that contains the actual header,
  81  	// in which case this image is a safe, new-style
  82  	// `cbfstool add-master-header` based image.
  83  
  84  	struct cbfs_file *entry, *first = NULL, *last = NULL;
  85  	for (first = entry = cbfs_find_first_entry(image);
  86  	     entry && cbfs_is_valid_entry(image, entry);
  87  	     entry = cbfs_find_next_entry(image, entry)) {
  88  		/* Is the header guarded by a CBFS file entry? Then exit */
  89  		if (((char *)entry) + be32toh(entry->offset) == hdr_loc)
  90  			return 0;
  91  		last = entry;
  92  	}
  93  	if ((char *)first < (char *)hdr_loc &&
  94  	    (char *)entry > (char *)hdr_loc) {
  95  		WARN("CBFS image was created with old cbfstool with size bug. "
  96  		     "Fixing size in last entry...\n");
  97  		last->len = htobe32(be32toh(last->len) - image->header.align);
  98  		DEBUG("Last entry has been changed from 0x%x to 0x%x.\n",
  99  		      cbfs_get_entry_addr(image, entry),
 100  		      cbfs_get_entry_addr(image,
 101  					  cbfs_find_next_entry(image, last)));
 102  	}
 103  	return 0;
 104  }
 105  
 106  void cbfs_put_header(void *dest, const struct cbfs_header *header)
 107  {
 108  	struct buffer outheader;
 109  
 110  	outheader.data = dest;
 111  	outheader.size = 0;
 112  
 113  	xdr_be.put32(&outheader, header->magic);
 114  	xdr_be.put32(&outheader, header->version);
 115  	xdr_be.put32(&outheader, header->romsize);
 116  	xdr_be.put32(&outheader, header->bootblocksize);
 117  	xdr_be.put32(&outheader, header->align);
 118  	xdr_be.put32(&outheader, header->offset);
 119  	xdr_be.put32(&outheader, header->architecture);
 120  }
 121  
 122  static void cbfs_decode_payload_segment(struct cbfs_payload_segment *output,
 123  					struct cbfs_payload_segment *input)
 124  {
 125  	struct buffer seg = {
 126  		.data = (void *)input,
 127  		.size = sizeof(*input),
 128  	};
 129  	output->type = xdr_be.get32(&seg);
 130  	output->compression = xdr_be.get32(&seg);
 131  	output->offset = xdr_be.get32(&seg);
 132  	output->load_addr = xdr_be.get64(&seg);
 133  	output->len = xdr_be.get32(&seg);
 134  	output->mem_len = xdr_be.get32(&seg);
 135  	assert(seg.size == 0);
 136  }
 137  
 138  static int cbfs_file_get_compression_info(struct cbfs_file *entry,
 139  	uint32_t *decompressed_size)
 140  {
 141  	unsigned int compression = CBFS_COMPRESS_NONE;
 142  	if (decompressed_size)
 143  		*decompressed_size = be32toh(entry->len);
 144  	for (struct cbfs_file_attribute *attr = cbfs_file_first_attr(entry);
 145  	     attr != NULL;
 146  	     attr = cbfs_file_next_attr(entry, attr)) {
 147  		if (be32toh(attr->tag) == CBFS_FILE_ATTR_TAG_COMPRESSION) {
 148  			struct cbfs_file_attr_compression *ac =
 149  				(struct cbfs_file_attr_compression *)attr;
 150  			compression = be32toh(ac->compression);
 151  			if (decompressed_size)
 152  				*decompressed_size =
 153  					be32toh(ac->decompressed_size);
 154  		}
 155  	}
 156  	return compression;
 157  }
 158  
 159  static struct cbfs_file_attr_hash *cbfs_file_get_next_hash(
 160  	struct cbfs_file *entry, struct cbfs_file_attr_hash *cur)
 161  {
 162  	struct cbfs_file_attribute *attr = (struct cbfs_file_attribute *)cur;
 163  	if (attr == NULL) {
 164  		attr = cbfs_file_first_attr(entry);
 165  		if (attr == NULL)
 166  			return NULL;
 167  		if (be32toh(attr->tag) == CBFS_FILE_ATTR_TAG_HASH)
 168  			return (struct cbfs_file_attr_hash *)attr;
 169  	}
 170  	while ((attr = cbfs_file_next_attr(entry, attr)) != NULL) {
 171  		if (be32toh(attr->tag) == CBFS_FILE_ATTR_TAG_HASH)
 172  			return (struct cbfs_file_attr_hash *)attr;
 173  	};
 174  	return NULL;
 175  }
 176  
 177  void cbfs_get_header(struct cbfs_header *header, void *src)
 178  {
 179  	struct buffer outheader;
 180  
 181  	outheader.data = src;	/* We're not modifying the data */
 182  	outheader.size = 0;
 183  
 184  	header->magic = xdr_be.get32(&outheader);
 185  	header->version = xdr_be.get32(&outheader);
 186  	header->romsize = xdr_be.get32(&outheader);
 187  	header->bootblocksize = xdr_be.get32(&outheader);
 188  	header->align = xdr_be.get32(&outheader);
 189  	header->offset = xdr_be.get32(&outheader);
 190  	header->architecture = xdr_be.get32(&outheader);
 191  }
 192  
 193  int cbfs_image_create(struct cbfs_image *image, size_t entries_size)
 194  {
 195  	assert(image);
 196  	assert(image->buffer.data);
 197  
 198  	size_t empty_header_len = cbfs_calculate_file_header_size("");
 199  	uint32_t entries_offset = 0;
 200  	uint32_t align = CBFS_ALIGNMENT;
 201  	if (image->has_header) {
 202  		entries_offset = image->header.offset;
 203  
 204  		if (entries_offset > image->buffer.size) {
 205  			ERROR("CBFS file entries are located outside CBFS itself\n");
 206  			return -1;
 207  		}
 208  
 209  		align = image->header.align;
 210  	}
 211  
 212  	// This attribute must be given in order to prove that this module
 213  	// correctly preserves certain CBFS properties. See the block comment
 214  	// near the top of this file (and the associated commit message).
 215  	if (align < empty_header_len) {
 216  		ERROR("CBFS must be aligned to at least %zu bytes\n",
 217  							empty_header_len);
 218  		return -1;
 219  	}
 220  
 221  	if (entries_size > image->buffer.size - entries_offset) {
 222  		ERROR("CBFS doesn't have enough space to fit its file entries\n");
 223  		return -1;
 224  	}
 225  
 226  	if (empty_header_len > entries_size) {
 227  		ERROR("CBFS is too small to fit any header\n");
 228  		return -1;
 229  	}
 230  	struct cbfs_file *entry_header =
 231  		(struct cbfs_file *)(image->buffer.data + entries_offset);
 232  	// This alignment is necessary in order to prove that this module
 233  	// correctly preserves certain CBFS properties. See the block comment
 234  	// near the top of this file (and the associated commit message).
 235  	entries_size -= entries_size % align;
 236  
 237  	size_t capacity = entries_size - empty_header_len;
 238  	LOG("Created CBFS (capacity = %zu bytes)\n", capacity);
 239  	return cbfs_create_empty_entry(entry_header, CBFS_TYPE_NULL,
 240  		capacity, "");
 241  }
 242  
 243  int cbfs_legacy_image_create(struct cbfs_image *image,
 244  			     uint32_t architecture,
 245  			     uint32_t align,
 246  			     struct buffer *bootblock,
 247  			     uint32_t bootblock_offset,
 248  			     uint32_t header_offset,
 249  			     uint32_t entries_offset)
 250  {
 251  	assert(image);
 252  	assert(image->buffer.data);
 253  	assert(bootblock);
 254  
 255  	int32_t *rel_offset;
 256  	uint32_t cbfs_len;
 257  	void *header_loc;
 258  	size_t size = image->buffer.size;
 259  
 260  	DEBUG("cbfs_image_create: bootblock=0x%x+0x%zx, "
 261  	      "header=0x%x+0x%zx, entries_offset=0x%x\n",
 262  	      bootblock_offset, bootblock->size, header_offset,
 263  	      sizeof(image->header), entries_offset);
 264  
 265  	DEBUG("cbfs_create_image: (real offset) bootblock=0x%x, "
 266  	      "header=0x%x, entries_offset=0x%x\n",
 267  	      bootblock_offset, header_offset, entries_offset);
 268  
 269  	// Prepare bootblock
 270  	if (bootblock_offset + bootblock->size > size) {
 271  		ERROR("Bootblock (0x%x+0x%zx) exceed ROM size (0x%zx)\n",
 272  		      bootblock_offset, bootblock->size, size);
 273  		return -1;
 274  	}
 275  	if (entries_offset > bootblock_offset &&
 276  	    entries_offset < bootblock->size) {
 277  		ERROR("Bootblock (0x%x+0x%zx) overlap CBFS data (0x%x)\n",
 278  		      bootblock_offset, bootblock->size, entries_offset);
 279  		return -1;
 280  	}
 281  	memcpy(image->buffer.data + bootblock_offset, bootblock->data,
 282  	       bootblock->size);
 283  
 284  	// Prepare header
 285  	if (header_offset + sizeof(image->header) > size - sizeof(int32_t)) {
 286  		ERROR("Header (0x%x+0x%zx) exceed ROM size (0x%zx)\n",
 287  		      header_offset, sizeof(image->header), size);
 288  		return -1;
 289  	}
 290  	image->header.magic = CBFS_HEADER_MAGIC;
 291  	image->header.version = CBFS_HEADER_VERSION;
 292  	image->header.romsize = size;
 293  	image->header.bootblocksize = bootblock->size;
 294  	image->header.align = align;
 295  	image->header.offset = entries_offset;
 296  	image->header.architecture = architecture;
 297  
 298  	header_loc = (image->buffer.data + header_offset);
 299  	cbfs_put_header(header_loc, &image->header);
 300  	image->has_header = true;
 301  
 302  	// The last 4 byte of the image contain the relative offset from the end
 303  	// of the image to the master header as a 32-bit signed integer. x86
 304  	// relies on this also being its (memory-mapped, top-aligned) absolute
 305  	// 32-bit address by virtue of how two's complement numbers work.
 306  	assert(size % sizeof(int32_t) == 0);
 307  	rel_offset = (int32_t *)(image->buffer.data + size - sizeof(int32_t));
 308  	*rel_offset = header_offset - size;
 309  
 310  	// Prepare entries
 311  	if (align_up(entries_offset, align) != entries_offset) {
 312  		ERROR("Offset (0x%x) must be aligned to 0x%x.\n",
 313  		      entries_offset, align);
 314  		return -1;
 315  	}
 316  	// To calculate available length, find
 317  	//   e = min(bootblock, header, rel_offset) where e > entries_offset.
 318  	cbfs_len = size - sizeof(int32_t);
 319  	if (bootblock_offset > entries_offset && bootblock_offset < cbfs_len)
 320  		cbfs_len = bootblock_offset;
 321  	if (header_offset > entries_offset && header_offset < cbfs_len)
 322  		cbfs_len = header_offset;
 323  
 324  	if (cbfs_image_create(image, cbfs_len - entries_offset))
 325  		return -1;
 326  	return 0;
 327  }
 328  
 329  int cbfs_image_from_buffer(struct cbfs_image *out, struct buffer *in,
 330  			   uint32_t offset)
 331  {
 332  	assert(out);
 333  	assert(in);
 334  	assert(in->data);
 335  
 336  	buffer_clone(&out->buffer, in);
 337  	out->has_header = false;
 338  
 339  	if (cbfs_is_valid_cbfs(out)) {
 340  		return 0;
 341  	}
 342  
 343  	void *header_loc = cbfs_find_header(in->data, in->size, offset);
 344  	if (header_loc) {
 345  		cbfs_get_header(&out->header, header_loc);
 346  		out->has_header = true;
 347  		cbfs_fix_legacy_size(out, header_loc);
 348  		return 0;
 349  	} else if (offset != HEADER_OFFSET_UNKNOWN) {
 350  		ERROR("The -H switch is only valid on legacy images having CBFS master headers.\n");
 351  	}
 352  	ERROR("Selected image region is not a valid CBFS.\n");
 353  	return 1;
 354  }
 355  
 356  int cbfs_copy_instance(struct cbfs_image *image, struct buffer *dst)
 357  {
 358  	assert(image);
 359  
 360  	struct cbfs_file *src_entry, *dst_entry;
 361  	size_t align;
 362  	ssize_t last_entry_size;
 363  
 364  	size_t copy_end = buffer_size(dst);
 365  
 366  	align = CBFS_ALIGNMENT;
 367  
 368  	dst_entry = (struct cbfs_file *)buffer_get(dst);
 369  
 370  	/* Copy non-empty files */
 371  	for (src_entry = cbfs_find_first_entry(image);
 372  	     src_entry && cbfs_is_valid_entry(image, src_entry);
 373  	     src_entry = cbfs_find_next_entry(image, src_entry)) {
 374  		size_t entry_size;
 375  
 376  		if ((src_entry->type == htobe32(CBFS_TYPE_NULL)) ||
 377  		    (src_entry->type == htobe32(CBFS_TYPE_CBFSHEADER)) ||
 378  		    (src_entry->type == htobe32(CBFS_TYPE_DELETED)))
 379  			continue;
 380  
 381  		entry_size = htobe32(src_entry->len) + htobe32(src_entry->offset);
 382  		memcpy(dst_entry, src_entry, entry_size);
 383  		dst_entry = (struct cbfs_file *)(
 384  			(uintptr_t)dst_entry + align_up(entry_size, align));
 385  
 386  		if ((size_t)((uint8_t *)dst_entry - (uint8_t *)buffer_get(dst))
 387  					>= copy_end) {
 388  			ERROR("Ran out of room in copy region.\n");
 389  			return 1;
 390  		}
 391  	}
 392  
 393  	/* Last entry size is all the room above it, except for top 4 bytes
 394  	 * which may be used by the master header pointer. This messes with
 395  	 * the ability to stash something "top-aligned" into the region, but
 396  	 * keeps things simpler. */
 397  	last_entry_size = copy_end -
 398  		((uint8_t *)dst_entry - (uint8_t *)buffer_get(dst)) -
 399  		cbfs_calculate_file_header_size("") - sizeof(int32_t);
 400  
 401  	if (last_entry_size < 0)
 402  		WARN("No room to create the last entry!\n");
 403  	else
 404  		return cbfs_create_empty_entry(dst_entry, CBFS_TYPE_NULL,
 405  					       last_entry_size, "");
 406  
 407  	return 0;
 408  }
 409  
 410  int cbfs_expand_to_region(struct buffer *region)
 411  {
 412  	if (buffer_get(region) == NULL)
 413  		return 1;
 414  
 415  	struct cbfs_image image;
 416  	memset(&image, 0, sizeof(image));
 417  	if (cbfs_image_from_buffer(&image, region, HEADER_OFFSET_UNKNOWN)) {
 418  		ERROR("reading CBFS failed!\n");
 419  		return 1;
 420  	}
 421  
 422  	uint32_t region_sz = buffer_size(region);
 423  
 424  	struct cbfs_file *entry;
 425  	for (entry = buffer_get(region);
 426  	     cbfs_is_valid_entry(&image, entry);
 427  	     entry = cbfs_find_next_entry(&image, entry)) {
 428  	     /* just iterate through */
 429  	}
 430  
 431  	/* entry now points to the first aligned address after the last valid
 432  	 * file header. That's either outside the image or exactly the place
 433  	 * where we need to create a new file.
 434  	 */
 435  	int last_entry_size = region_sz -
 436  		((uint8_t *)entry - (uint8_t *)buffer_get(region)) -
 437  		cbfs_calculate_file_header_size("") - sizeof(int32_t);
 438  
 439  	if (last_entry_size > 0) {
 440  		if (cbfs_create_empty_entry(entry, CBFS_TYPE_NULL,
 441  					    last_entry_size, ""))
 442  			return 1;
 443  
 444  		/* If the last entry was an empty file, merge them. */
 445  		cbfs_legacy_walk(&image, cbfs_merge_empty_entry, NULL);
 446  	}
 447  
 448  	return 0;
 449  }
 450  
 451  int cbfs_truncate_space(struct buffer *region, uint32_t *size)
 452  {
 453  	if (buffer_get(region) == NULL)
 454  		return 1;
 455  
 456  	struct cbfs_image image;
 457  	memset(&image, 0, sizeof(image));
 458  	if (cbfs_image_from_buffer(&image, region, HEADER_OFFSET_UNKNOWN)) {
 459  		ERROR("reading CBFS failed!\n");
 460  		return 1;
 461  	}
 462  
 463  	struct cbfs_file *entry, *trailer;
 464  	for (trailer = entry = buffer_get(region);
 465  	     cbfs_is_valid_entry(&image, entry);
 466  	     trailer = entry,
 467  	     entry = cbfs_find_next_entry(&image, entry)) {
 468  	     /* just iterate through */
 469  	}
 470  
 471  	/* trailer now points to the last valid CBFS entry's header.
 472  	 * If that file is empty, remove it and report its header's offset as
 473  	 * maximum size.
 474  	 */
 475  	if ((strlen(trailer->filename) != 0) &&
 476  	    (trailer->type != htobe32(CBFS_TYPE_NULL)) &&
 477  	    (trailer->type != htobe32(CBFS_TYPE_DELETED))) {
 478  		/* nothing to truncate. Return de-facto CBFS size in case it
 479  		 * was already truncated. */
 480  		*size = (uint8_t *)entry - (uint8_t *)buffer_get(region);
 481  		return 0;
 482  	}
 483  	*size = (uint8_t *)trailer - (uint8_t *)buffer_get(region);
 484  	memset(trailer, 0xff, buffer_size(region) - *size);
 485  
 486  	return 0;
 487  }
 488  
 489  static size_t cbfs_file_entry_metadata_size(const struct cbfs_file *f)
 490  {
 491  	return be32toh(f->offset);
 492  }
 493  
 494  static size_t cbfs_file_entry_data_size(const struct cbfs_file *f)
 495  {
 496  	return be32toh(f->len);
 497  }
 498  
 499  static size_t cbfs_file_entry_size(const struct cbfs_file *f)
 500  {
 501  	return cbfs_file_entry_metadata_size(f) + cbfs_file_entry_data_size(f);
 502  }
 503  
 504  int cbfs_compact_instance(struct cbfs_image *image)
 505  {
 506  	assert(image);
 507  
 508  	struct cbfs_file *prev;
 509  	struct cbfs_file *cur;
 510  
 511  	/* The prev entry will always be an empty entry. */
 512  	prev = NULL;
 513  
 514  	/*
 515  	 * Note: this function does not honor alignment or fixed location files.
 516  	 * It's behavior is akin to cbfs_copy_instance() in that it expects
 517  	 * the caller to understand the ramifications of compacting a
 518  	 * fragmented CBFS image.
 519  	 */
 520  
 521  	for (cur = cbfs_find_first_entry(image);
 522  	     cur && cbfs_is_valid_entry(image, cur);
 523  	     cur = cbfs_find_next_entry(image, cur)) {
 524  		size_t prev_size;
 525  		size_t cur_size;
 526  		size_t empty_metadata_size;
 527  		size_t spill_size;
 528  
 529  		/* Current entry is empty. Kepp track of it. */
 530  		if (cur->type == CBFS_TYPE_NULL || cur->type == CBFS_TYPE_DELETED) {
 531  			prev = cur;
 532  			continue;
 533  		}
 534  
 535  		/* Need to ensure the previous entry is an empty one. */
 536  		if (prev == NULL)
 537  			continue;
 538  
 539  		/* At this point prev is an empty entry. Put the non-empty
 540  		 * file in prev's location. Then add a new empty entry. This
 541  		 * essentialy bubbles empty entries towards the end. */
 542  
 543  		prev_size = cbfs_file_entry_size(prev);
 544  		cur_size = cbfs_file_entry_size(cur);
 545  
 546  		/*
 547  		 * Adjust the empty file size by the actual space occupied
 548  		 * bewtween the beginning of the empty file and the non-empty
 549  		 * file.
 550  		 */
 551  		prev_size += (cbfs_get_entry_addr(image, cur) -
 552  				cbfs_get_entry_addr(image, prev)) - prev_size;
 553  
 554  		/* Move the non-empty file over the empty file. */
 555  		memmove(prev, cur, cur_size);
 556  
 557  		/*
 558  		 * Get location of the empty file. Note that since prev was
 559  		 * overwritten with the non-empty file the previously moved
 560  		 * file needs to be used to calculate the empty file's location.
 561  		 */
 562  		cur = cbfs_find_next_entry(image, prev);
 563  
 564  		/*
 565  		 * The total space to work with for swapping the 2 entries
 566  		 * consists of the 2 files' sizes combined. However, the
 567  		 * cbfs_file entries start on CBFS_ALIGNMENT boundaries.
 568  		 * Because of this the empty file size may end up smaller
 569  		 * because of the non-empty file's metadata and data length.
 570  		 *
 571  		 * Calculate the spill size which is the amount of data lost
 572  		 * due to the alignment constraints after moving the non-empty
 573  		 * file.
 574  		 */
 575  		spill_size = (cbfs_get_entry_addr(image, cur) -
 576  				cbfs_get_entry_addr(image, prev)) - cur_size;
 577  
 578  		empty_metadata_size = cbfs_calculate_file_header_size("");
 579  
 580  		/* Check if new empty size can contain the metadata. */
 581  		if (empty_metadata_size + spill_size > prev_size) {
 582  			ERROR("Unable to swap '%s' with prev empty entry.\n",
 583  				prev->filename);
 584  			return 1;
 585  		}
 586  
 587  		/* Update the empty file's size. */
 588  		prev_size -= spill_size + empty_metadata_size;
 589  
 590  		/* Create new empty file. */
 591  		if (cbfs_create_empty_entry(cur, CBFS_TYPE_NULL,
 592  					    prev_size, ""))
 593  			return 1;
 594  
 595  		/* Merge any potential empty entries together. */
 596  		cbfs_legacy_walk(image, cbfs_merge_empty_entry, NULL);
 597  
 598  		/*
 599  		 * Since current switched to an empty file keep track of it.
 600  		 * Even if any empty files were merged the empty entry still
 601  		 * starts at previously calculated location.
 602  		 */
 603  		prev = cur;
 604  	}
 605  
 606  	return 0;
 607  }
 608  
 609  int cbfs_image_delete(struct cbfs_image *image)
 610  {
 611  	if (image == NULL)
 612  		return 0;
 613  
 614  	buffer_delete(&image->buffer);
 615  	return 0;
 616  }
 617  
 618  /* Tries to add an entry with its data (CBFS_SUBHEADER) at given offset. */
 619  static int cbfs_add_entry_at(struct cbfs_image *image,
 620  			     struct cbfs_file *entry,
 621  			     const void *data,
 622  			     uint32_t content_offset,
 623  			     const struct cbfs_file *header,
 624  			     const size_t len_align)
 625  {
 626  	struct cbfs_file *next = cbfs_find_next_entry(image, entry);
 627  	uint32_t addr = cbfs_get_entry_addr(image, entry),
 628  		 addr_next = cbfs_get_entry_addr(image, next);
 629  	uint32_t min_entry_size = cbfs_calculate_file_header_size("");
 630  	uint32_t len, header_offset;
 631  	uint32_t align = image->has_header ? image->header.align :
 632  							CBFS_ALIGNMENT;
 633  	uint32_t header_size = be32toh(header->offset);
 634  
 635  	header_offset = content_offset - header_size;
 636  	if (header_offset % align)
 637  		header_offset -= header_offset % align;
 638  	if (header_offset < addr) {
 639  		ERROR("No space to hold cbfs_file header.");
 640  		return -1;
 641  	}
 642  
 643  	// Process buffer BEFORE content_offset.
 644  	if (header_offset - addr > min_entry_size) {
 645  		DEBUG("|min|...|header|content|... <create new entry>\n");
 646  		len = header_offset - addr - min_entry_size;
 647  		if (cbfs_create_empty_entry(entry, CBFS_TYPE_NULL, len, ""))
 648  			return -1;
 649  		if (verbose > 1) cbfs_print_entry_info(image, entry, stderr);
 650  		entry = cbfs_find_next_entry(image, entry);
 651  		addr = cbfs_get_entry_addr(image, entry);
 652  	}
 653  
 654  	len = content_offset - addr - header_size;
 655  	memcpy(entry, header, header_size);
 656  	if (len != 0) {
 657  		/*
 658  		 * The header moved backwards a bit to accommodate cbfs_file
 659  		 * alignment requirements, so patch up ->offset to still point
 660  		 * to file data. Move attributes forward so the end of the
 661  		 * attribute list still matches the end of the metadata.
 662  		 */
 663  		uint32_t offset = be32toh(entry->offset);
 664  		uint32_t attrs = be32toh(entry->attributes_offset);
 665  		DEBUG("|..|header|content|... <use offset to create entry>\n");
 666  		DEBUG("before: attr_offset=0x%x, offset=0x%x\n", attrs, offset);
 667  		if (attrs == 0) {
 668  			memset((uint8_t *)entry + offset, 0, len);
 669  		} else {
 670  			uint8_t *p = (uint8_t *)entry + attrs;
 671  			memmove(p + len, p, offset - attrs);
 672  			memset(p, 0, len);
 673  			attrs += len;
 674  			entry->attributes_offset = htobe32(attrs);
 675  		}
 676  		offset += len;
 677  		entry->offset = htobe32(offset);
 678  		DEBUG("after: attr_offset=0x%x, offset=0x%x\n", attrs, offset);
 679  	}
 680  
 681  	// Ready to fill data into entry.
 682  	DEBUG("content_offset: 0x%x, entry location: %x\n",
 683  	      content_offset, (int)((char*)CBFS_SUBHEADER(entry) -
 684  				    image->buffer.data));
 685  	assert((char*)CBFS_SUBHEADER(entry) - image->buffer.data ==
 686  	       (ptrdiff_t)content_offset);
 687  	memcpy(CBFS_SUBHEADER(entry), data, be32toh(entry->len));
 688  	if (verbose > 1) cbfs_print_entry_info(image, entry, stderr);
 689  
 690  	// Align the length to a multiple of len_align
 691  	if (len_align &&
 692  	    ((be32toh(entry->offset) + be32toh(entry->len)) % len_align)) {
 693  		size_t off = (be32toh(entry->offset) + be32toh(entry->len)) % len_align;
 694  		entry->len = htobe32(be32toh(entry->len) + len_align - off);
 695  	}
 696  
 697  	// Process buffer AFTER entry.
 698  	entry = cbfs_find_next_entry(image, entry);
 699  	addr = cbfs_get_entry_addr(image, entry);
 700  	if (addr == addr_next)
 701  		return 0;
 702  
 703  	assert(addr < addr_next);
 704  	if (addr_next - addr < min_entry_size) {
 705  		DEBUG("No need for new \"empty\" entry\n");
 706  		/* No need to increase the size of the just
 707  		 * stored file to extend to next file. Alignment
 708  		 * of next file takes care of this.
 709  		 */
 710  		return 0;
 711  	}
 712  
 713  	len = addr_next - addr - min_entry_size;
 714  	/* keep space for master header pointer */
 715  	if ((uint8_t *)entry + min_entry_size + len >
 716  			(uint8_t *)buffer_get(&image->buffer) +
 717  			buffer_size(&image->buffer) - sizeof(int32_t)) {
 718  		len -= sizeof(int32_t);
 719  	}
 720  	if (cbfs_create_empty_entry(entry, CBFS_TYPE_NULL, len, ""))
 721  		return -1;
 722  	if (verbose > 1) cbfs_print_entry_info(image, entry, stderr);
 723  	return 0;
 724  }
 725  
 726  int cbfs_add_entry(struct cbfs_image *image, struct buffer *buffer,
 727  		   uint32_t content_offset,
 728  		   struct cbfs_file *header,
 729  		   const size_t len_align)
 730  {
 731  	assert(image);
 732  	assert(buffer);
 733  	assert(buffer->data);
 734  	assert(!IS_HOST_SPACE_ADDRESS(content_offset));
 735  
 736  	const char *name = header->filename;
 737  
 738  	/* This is so special rows in cbfstool print -k -v output stay unambiguous. */
 739  	if (name[0] == '[') {
 740  		ERROR("CBFS file name `%s` must not start with `[`\n", name);
 741  		return -1;
 742  	}
 743  
 744  	uint32_t entry_type;
 745  	uint32_t addr, addr_next;
 746  	uint32_t entry_size;
 747  	uint32_t max_null_entry_size = 0;
 748  	struct cbfs_file *entry, *next;
 749  	uint32_t need_size;
 750  	uint32_t header_size = be32toh(header->offset);
 751  
 752  	need_size = header_size + buffer->size;
 753  	DEBUG("cbfs_add_entry('%s'@0x%x) => need_size = %u+%zu=%u\n",
 754  	      name, content_offset, header_size, buffer->size, need_size);
 755  
 756  	// Merge empty entries.
 757  	DEBUG("(trying to merge empty entries...)\n");
 758  	cbfs_legacy_walk(image, cbfs_merge_empty_entry, NULL);
 759  
 760  	for (entry = cbfs_find_first_entry(image);
 761  	     entry && cbfs_is_valid_entry(image, entry);
 762  	     entry = cbfs_find_next_entry(image, entry)) {
 763  
 764  		entry_type = be32toh(entry->type);
 765  		if (entry_type != CBFS_TYPE_NULL)
 766  			continue;
 767  
 768  		addr = cbfs_get_entry_addr(image, entry);
 769  		next = cbfs_find_next_entry(image, entry);
 770  		addr_next = cbfs_get_entry_addr(image, next);
 771  		entry_size = addr_next - addr;
 772  		max_null_entry_size = MAX(max_null_entry_size, entry_size);
 773  
 774  		DEBUG("cbfs_add_entry: space at 0x%x+0x%x(%d) bytes\n",
 775  		      addr, entry_size, entry_size);
 776  
 777  		/* Will the file fit? Don't yet worry if we have space for a new
 778  		 * "empty" entry. We take care of that later.
 779  		 */
 780  		if (addr + need_size > addr_next)
 781  			continue;
 782  
 783  		// Test for complicated cases
 784  		if (content_offset > 0) {
 785  			if (addr_next < content_offset) {
 786  				DEBUG("Not for specified offset yet");
 787  				continue;
 788  			} else if (addr > content_offset) {
 789  				DEBUG("Exceed specified content_offset.");
 790  				break;
 791  			} else if (addr + header_size > content_offset) {
 792  				ERROR("Not enough space for header.\n");
 793  				break;
 794  			} else if (content_offset + buffer->size > addr_next) {
 795  				ERROR("Not enough space for content.\n");
 796  				break;
 797  			}
 798  		}
 799  
 800  		// TODO there are more few tricky cases that we may
 801  		// want to fit by altering offset.
 802  
 803  		if (content_offset == 0) {
 804  			// we tested every condition earlier under which
 805  			// placing the file there might fail
 806  			content_offset = addr + header_size;
 807  		}
 808  
 809  		DEBUG("section 0x%x+0x%x for content_offset 0x%x.\n",
 810  		      addr, entry_size, content_offset);
 811  
 812  		if (cbfs_add_entry_at(image, entry, buffer->data,
 813  				      content_offset, header, len_align) == 0) {
 814  			return 0;
 815  		}
 816  		break;
 817  	}
 818  
 819  	ERROR("Could not add %s [header %d + content %zd bytes (%zd KB)] @0x%x; "
 820  	      "Largest empty slot: %d bytes\n",
 821  	      buffer->name, header_size, buffer->size, buffer->size / 1024, content_offset,
 822  	      max_null_entry_size);
 823  	return -1;
 824  }
 825  
 826  struct cbfs_file *cbfs_get_entry(struct cbfs_image *image, const char *name)
 827  {
 828  	struct cbfs_file *entry;
 829  	for (entry = cbfs_find_first_entry(image);
 830  	     entry && cbfs_is_valid_entry(image, entry);
 831  	     entry = cbfs_find_next_entry(image, entry)) {
 832  		if (strcasecmp(entry->filename, name) == 0) {
 833  			DEBUG("cbfs_get_entry: found %s\n", name);
 834  			return entry;
 835  		}
 836  	}
 837  	return NULL;
 838  }
 839  
 840  static int cbfs_payload_decompress(struct cbfs_payload_segment *segments,
 841  		struct buffer *buff, int num_seg)
 842  {
 843  	struct buffer new_buffer;
 844  	struct buffer seg_buffer;
 845  	size_t new_buff_sz;
 846  	char *in_ptr;
 847  	char *out_ptr;
 848  	size_t new_offset;
 849  	decomp_func_ptr decompress;
 850  
 851  	new_offset = num_seg * sizeof(*segments);
 852  	new_buff_sz = num_seg * sizeof(*segments);
 853  
 854  	/* Find out and allocate the amount of memory occupied
 855  	 * by the binary data */
 856  	for (int i = 0; i < num_seg; i++)
 857  		new_buff_sz += segments[i].mem_len;
 858  
 859  	if (buffer_create(&new_buffer, new_buff_sz, "decompressed_buff"))
 860  		return -1;
 861  
 862  	in_ptr = buffer_get(buff) + new_offset;
 863  	out_ptr = buffer_get(&new_buffer) + new_offset;
 864  
 865  	for (int i = 0; i < num_seg; i++) {
 866  		struct buffer tbuff;
 867  		size_t decomp_size;
 868  
 869  		/* Segments BSS and ENTRY do not have binary data. */
 870  		if (segments[i].type == PAYLOAD_SEGMENT_BSS ||
 871  				segments[i].type == PAYLOAD_SEGMENT_ENTRY) {
 872  			continue;
 873  		} else if (segments[i].type == PAYLOAD_SEGMENT_DEPRECATED_PARAMS) {
 874  			memcpy(out_ptr, in_ptr, segments[i].len);
 875  			segments[i].offset = new_offset;
 876  			new_offset += segments[i].len;
 877  			in_ptr += segments[i].len;
 878  			out_ptr += segments[i].len;
 879  			segments[i].compression = CBFS_COMPRESS_NONE;
 880  			continue;
 881  		}
 882  
 883  		/* The payload uses an unknown compression algorithm. */
 884  		decompress = decompression_function(segments[i].compression);
 885  		if (decompress == NULL) {
 886  			ERROR("Unknown decompression algorithm: %u\n",
 887  					segments[i].compression);
 888  			return -1;
 889  		}
 890  
 891  		if (buffer_create(&tbuff, segments[i].mem_len, "segment")) {
 892  			buffer_delete(&new_buffer);
 893  			return -1;
 894  		}
 895  
 896  		if (decompress(in_ptr, segments[i].len, buffer_get(&tbuff),
 897  					(int) buffer_size(&tbuff),
 898  					&decomp_size)) {
 899  			ERROR("Couldn't decompress payload segment %u\n", i);
 900  			buffer_delete(&new_buffer);
 901  			buffer_delete(&tbuff);
 902  			return -1;
 903  		}
 904  
 905  		memcpy(out_ptr, buffer_get(&tbuff), decomp_size);
 906  
 907  		in_ptr += segments[i].len;
 908  
 909  		/* Update the offset of the segment. */
 910  		segments[i].offset = new_offset;
 911  		/* True decompressed size is just the data size. No metadata */
 912  		segments[i].len = decomp_size;
 913  		/* Segment is not compressed. */
 914  		segments[i].compression = CBFS_COMPRESS_NONE;
 915  
 916  		/* Update the offset and output buffer pointer. */
 917  		new_offset += decomp_size;
 918  		out_ptr += decomp_size;
 919  
 920  		buffer_delete(&tbuff);
 921  	}
 922  
 923  	buffer_splice(&seg_buffer, &new_buffer, 0, 0);
 924  	xdr_segs(&seg_buffer, segments, num_seg);
 925  
 926  	buffer_delete(buff);
 927  	*buff = new_buffer;
 928  
 929  	return 0;
 930  }
 931  
 932  static int init_elf_from_arch(Elf64_Ehdr *ehdr, uint32_t cbfs_arch)
 933  {
 934  	int endian;
 935  	int nbits;
 936  	int machine;
 937  
 938  	switch (cbfs_arch) {
 939  	case CBFS_ARCHITECTURE_X86:
 940  		endian = ELFDATA2LSB;
 941  		nbits = ELFCLASS32;
 942  		machine = EM_386;
 943  		break;
 944  	case CBFS_ARCHITECTURE_ARM:
 945  		endian = ELFDATA2LSB;
 946  		nbits = ELFCLASS32;
 947  		machine = EM_ARM;
 948  		break;
 949  	case CBFS_ARCHITECTURE_AARCH64:
 950  		endian = ELFDATA2LSB;
 951  		nbits = ELFCLASS64;
 952  		machine = EM_AARCH64;
 953  		break;
 954  	case CBFS_ARCHITECTURE_MIPS:
 955  		endian = ELFDATA2LSB;
 956  		nbits = ELFCLASS32;
 957  		machine = EM_MIPS;
 958  		break;
 959  	case CBFS_ARCHITECTURE_RISCV:
 960  		endian = ELFDATA2LSB;
 961  		nbits = ELFCLASS32;
 962  		machine = EM_RISCV;
 963  		break;
 964  	default:
 965  		ERROR("Unsupported arch: %x\n", cbfs_arch);
 966  		return -1;
 967  	}
 968  
 969  	elf_init_eheader(ehdr, machine, nbits, endian);
 970  	return 0;
 971  }
 972  
 973  static int cbfs_stage_make_elf(struct buffer *buff, uint32_t arch,
 974  			       struct cbfs_file *entry)
 975  {
 976  	Elf64_Ehdr ehdr;
 977  	Elf64_Shdr shdr;
 978  	struct elf_writer *ew;
 979  	struct buffer elf_out;
 980  	size_t empty_sz;
 981  	int rmod_ret;
 982  
 983  	if (arch == CBFS_ARCHITECTURE_UNKNOWN) {
 984  		ERROR("You need to specify -m ARCH.\n");
 985  		return -1;
 986  	}
 987  
 988  	struct cbfs_file_attr_stageheader *stage = NULL;
 989  	for (struct cbfs_file_attribute *attr = cbfs_file_first_attr(entry);
 990  	     attr != NULL; attr = cbfs_file_next_attr(entry, attr)) {
 991  		if (be32toh(attr->tag) == CBFS_FILE_ATTR_TAG_STAGEHEADER) {
 992  			stage = (struct cbfs_file_attr_stageheader *)attr;
 993  			break;
 994  		}
 995  	}
 996  
 997  	if (stage == NULL) {
 998  		ERROR("Stage header not found for %s\n", entry->filename);
 999  		return -1;
1000  	}
1001  
1002  	if (init_elf_from_arch(&ehdr, arch))
1003  		return -1;
1004  
1005  	/* Attempt rmodule translation first. */
1006  	rmod_ret = rmodule_stage_to_elf(&ehdr, buff);
1007  
1008  	if (rmod_ret < 0) {
1009  		ERROR("rmodule parsing failed\n");
1010  		return -1;
1011  	} else if (rmod_ret == 0)
1012  		return 0;
1013  
1014  	/* Rmodule couldn't do anything with the data. Continue on with SELF. */
1015  
1016  	ehdr.e_entry = be64toh(stage->loadaddr) + be32toh(stage->entry_offset);
1017  
1018  	ew = elf_writer_init(&ehdr);
1019  	if (ew == NULL) {
1020  		ERROR("Unable to init ELF writer.\n");
1021  		return -1;
1022  	}
1023  
1024  	memset(&shdr, 0, sizeof(shdr));
1025  	shdr.sh_type = SHT_PROGBITS;
1026  	shdr.sh_flags = SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR;
1027  	shdr.sh_addr = be64toh(stage->loadaddr);
1028  	shdr.sh_size = buffer_size(buff);
1029  	empty_sz = be32toh(stage->memlen) - buffer_size(buff);
1030  
1031  	if (elf_writer_add_section(ew, &shdr, buff, ".program")) {
1032  		ERROR("Unable to add ELF section: .program\n");
1033  		elf_writer_destroy(ew);
1034  		return -1;
1035  	}
1036  
1037  	if (empty_sz != 0) {
1038  		struct buffer b;
1039  
1040  		buffer_init(&b, NULL, NULL, 0);
1041  		memset(&shdr, 0, sizeof(shdr));
1042  		shdr.sh_type = SHT_NOBITS;
1043  		shdr.sh_flags = SHF_WRITE | SHF_ALLOC;
1044  		shdr.sh_addr = be64toh(stage->loadaddr) + buffer_size(buff);
1045  		shdr.sh_size = empty_sz;
1046  		if (elf_writer_add_section(ew, &shdr, &b, ".empty")) {
1047  			ERROR("Unable to add ELF section: .empty\n");
1048  			elf_writer_destroy(ew);
1049  			return -1;
1050  		}
1051  	}
1052  
1053  	if (elf_writer_serialize(ew, &elf_out)) {
1054  		ERROR("Unable to create ELF file from stage.\n");
1055  		elf_writer_destroy(ew);
1056  		return -1;
1057  	}
1058  
1059  	/* Flip buffer with the created ELF one. */
1060  	buffer_delete(buff);
1061  	*buff = elf_out;
1062  
1063  	elf_writer_destroy(ew);
1064  
1065  	return 0;
1066  }
1067  
1068  static int cbfs_payload_make_elf(struct buffer *buff, uint32_t arch,
1069  				 unused struct cbfs_file *entry)
1070  {
1071  	Elf64_Ehdr ehdr;
1072  	Elf64_Shdr shdr;
1073  	struct cbfs_payload_segment *segs = NULL;
1074  	struct elf_writer *ew = NULL;
1075  	struct buffer elf_out;
1076  	int segments = 0;
1077  	int retval = -1;
1078  
1079  	if (arch == CBFS_ARCHITECTURE_UNKNOWN) {
1080  		ERROR("You need to specify -m ARCH.\n");
1081  		goto out;
1082  	}
1083  
1084  	/* Count the number of segments inside buffer */
1085  	while (true) {
1086  		uint32_t payload_type = 0;
1087  
1088  		struct cbfs_payload_segment *seg;
1089  
1090  		seg = buffer_get(buff);
1091  		payload_type = read_be32(&seg[segments].type);
1092  
1093  		if (payload_type == PAYLOAD_SEGMENT_CODE) {
1094  			segments++;
1095  		} else if (payload_type == PAYLOAD_SEGMENT_DATA) {
1096  			segments++;
1097  		} else if (payload_type == PAYLOAD_SEGMENT_BSS) {
1098  			segments++;
1099  		} else if (payload_type == PAYLOAD_SEGMENT_DEPRECATED_PARAMS) {
1100  			segments++;
1101  		} else if (payload_type == PAYLOAD_SEGMENT_ENTRY) {
1102  			/* The last segment in a payload is always ENTRY as
1103  			 * specified by the  parse_elf_to_payload() function.
1104  			 * Therefore there is no need to continue looking for
1105  			 * segments.*/
1106  			segments++;
1107  			break;
1108  		} else {
1109  			ERROR("Unknown payload segment type: %x\n",
1110  					payload_type);
1111  			goto out;
1112  		}
1113  	}
1114  
1115  	segs = malloc(segments * sizeof(*segs));
1116  
1117  	/* Decode xdr segments */
1118  	for (int i = 0; i < segments; i++) {
1119  		struct cbfs_payload_segment *serialized_seg = buffer_get(buff);
1120  		xdr_get_seg(&segs[i], &serialized_seg[i]);
1121  	}
1122  
1123  	if (cbfs_payload_decompress(segs, buff, segments)) {
1124  		ERROR("Failed to decompress payload.\n");
1125  		goto out;
1126  	}
1127  
1128  	if (init_elf_from_arch(&ehdr, arch))
1129  		goto out;
1130  
1131  	ehdr.e_entry = segs[segments-1].load_addr;
1132  
1133  	ew = elf_writer_init(&ehdr);
1134  	if (ew == NULL) {
1135  		ERROR("Unable to init ELF writer.\n");
1136  		goto out;
1137  	}
1138  
1139  	for (int i = 0; i < segments; i++) {
1140  		struct buffer tbuff;
1141  		size_t empty_sz = 0;
1142  
1143  		memset(&shdr, 0, sizeof(shdr));
1144  		char *name = NULL;
1145  
1146  		if (segs[i].type == PAYLOAD_SEGMENT_CODE) {
1147  			shdr.sh_type = SHT_PROGBITS;
1148  			shdr.sh_flags = SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR;
1149  			shdr.sh_addr = segs[i].load_addr;
1150  			shdr.sh_size = segs[i].len;
1151  			empty_sz = segs[i].mem_len - segs[i].len;
1152  			name = strdup(".text");
1153  			buffer_splice(&tbuff, buff, segs[i].offset,
1154  				       segs[i].len);
1155  		} else if (segs[i].type == PAYLOAD_SEGMENT_DATA) {
1156  			shdr.sh_type = SHT_PROGBITS;
1157  			shdr.sh_flags = SHF_ALLOC | SHF_WRITE;
1158  			shdr.sh_addr = segs[i].load_addr;
1159  			shdr.sh_size = segs[i].len;
1160  			empty_sz = segs[i].mem_len - segs[i].len;
1161  			name = strdup(".data");
1162  			buffer_splice(&tbuff, buff, segs[i].offset,
1163  				       segs[i].len);
1164  		} else if (segs[i].type == PAYLOAD_SEGMENT_BSS) {
1165  			shdr.sh_type = SHT_NOBITS;
1166  			shdr.sh_flags = SHF_ALLOC | SHF_WRITE;
1167  			shdr.sh_addr = segs[i].load_addr;
1168  			shdr.sh_size = segs[i].len;
1169  			name = strdup(".bss");
1170  			buffer_splice(&tbuff, buff, 0, 0);
1171  		} else if (segs[i].type == PAYLOAD_SEGMENT_DEPRECATED_PARAMS) {
1172  			shdr.sh_type = SHT_NOTE;
1173  			shdr.sh_flags = 0;
1174  			shdr.sh_size = segs[i].len;
1175  			name = strdup(".note.pinfo");
1176  			buffer_splice(&tbuff, buff, segs[i].offset,
1177  				       segs[i].len);
1178  		} else if (segs[i].type == PAYLOAD_SEGMENT_ENTRY) {
1179  			break;
1180  		} else {
1181  			ERROR("unknown ELF segment type\n");
1182  			goto out;
1183  		}
1184  
1185  		if (!name) {
1186  			ERROR("out of memory\n");
1187  			goto out;
1188  		}
1189  
1190  		if (elf_writer_add_section(ew, &shdr, &tbuff, name)) {
1191  			ERROR("Unable to add ELF section: %s\n", name);
1192  			free(name);
1193  			goto out;
1194  		}
1195  		free(name);
1196  
1197  		if (empty_sz != 0) {
1198  			struct buffer b;
1199  
1200  			buffer_init(&b, NULL, NULL, 0);
1201  			memset(&shdr, 0, sizeof(shdr));
1202  			shdr.sh_type = SHT_NOBITS;
1203  			shdr.sh_flags = SHF_WRITE | SHF_ALLOC;
1204  			shdr.sh_addr = segs[i].load_addr + segs[i].len;
1205  			shdr.sh_size = empty_sz;
1206  			name = strdup(".empty");
1207  			if (!name) {
1208  				ERROR("out of memory\n");
1209  				goto out;
1210  			}
1211  			if (elf_writer_add_section(ew, &shdr, &b, name)) {
1212  				ERROR("Unable to add ELF section: %s\n", name);
1213  				free(name);
1214  				goto out;
1215  			}
1216  			free(name);
1217  		}
1218  	}
1219  
1220  	if (elf_writer_serialize(ew, &elf_out)) {
1221  		ERROR("Unable to create ELF file from payload.\n");
1222  		goto out;
1223  	}
1224  
1225  	/* Flip buffer with the created ELF one. */
1226  	buffer_delete(buff);
1227  	*buff = elf_out;
1228  	retval = 0;
1229  
1230  out:
1231  	free(segs);
1232  	elf_writer_destroy(ew);
1233  	return retval;
1234  }
1235  
1236  int cbfs_export_entry(struct cbfs_image *image, const char *entry_name,
1237  		      const char *filename, uint32_t arch, bool do_processing)
1238  {
1239  	struct cbfs_file *entry = cbfs_get_entry(image, entry_name);
1240  	struct buffer buffer;
1241  	if (!entry) {
1242  		ERROR("File not found: %s\n", entry_name);
1243  		return -1;
1244  	}
1245  
1246  	unsigned int compressed_size = be32toh(entry->len);
1247  	unsigned int decompressed_size = 0;
1248  	unsigned int compression = cbfs_file_get_compression_info(entry,
1249  		&decompressed_size);
1250  	unsigned int buffer_len;
1251  	decomp_func_ptr decompress;
1252  
1253  	if (do_processing) {
1254  		decompress = decompression_function(compression);
1255  		if (!decompress) {
1256  			ERROR("looking up decompression routine failed\n");
1257  			return -1;
1258  		}
1259  		buffer_len = decompressed_size;
1260  	} else {
1261  		/* Force nop decompression */
1262  		decompress = decompression_function(CBFS_COMPRESS_NONE);
1263  		buffer_len = compressed_size;
1264  	}
1265  
1266  	LOG("Found file %.30s at 0x%x, type %.12s, compressed %d, size %d\n",
1267  	    entry_name, cbfs_get_entry_addr(image, entry),
1268  	    get_cbfs_entry_type_name(be32toh(entry->type)), compressed_size,
1269  	    decompressed_size);
1270  
1271  	buffer_init(&buffer, strdup("(cbfs_export_entry)"), NULL, 0);
1272  	buffer.data = malloc(buffer_len);
1273  	buffer.size = buffer_len;
1274  
1275  	if (decompress(CBFS_SUBHEADER(entry), compressed_size,
1276  		       buffer.data, buffer.size, NULL)) {
1277  		ERROR("decompression failed for %s\n", entry_name);
1278  		buffer_delete(&buffer);
1279  		return -1;
1280  	}
1281  
1282  	/*
1283  	 * We want to export stages and payloads as ELFs, not with coreboot's
1284  	 * custom stage/SELF binary formats, so we need to do extra processing
1285  	 * to turn them back into an ELF.
1286  	 */
1287  	if (do_processing) {
1288  		int (*make_elf)(struct buffer *, uint32_t,
1289  				struct cbfs_file *) = NULL;
1290  		switch (be32toh(entry->type)) {
1291  		case CBFS_TYPE_STAGE:
1292  			make_elf = cbfs_stage_make_elf;
1293  			break;
1294  		case CBFS_TYPE_SELF:
1295  			make_elf = cbfs_payload_make_elf;
1296  			break;
1297  		}
1298  		if (make_elf && make_elf(&buffer, arch, entry)) {
1299  			ERROR("Failed to write %s into %s.\n",
1300  			      entry_name, filename);
1301  			buffer_delete(&buffer);
1302  			return -1;
1303  		}
1304  	}
1305  
1306  	if (buffer_write_file(&buffer, filename) != 0) {
1307  		ERROR("Failed to write %s into %s.\n",
1308  		      entry_name, filename);
1309  		buffer_delete(&buffer);
1310  		return -1;
1311  	}
1312  
1313  	buffer_delete(&buffer);
1314  	INFO("Successfully dumped the file to: %s\n", filename);
1315  	return 0;
1316  }
1317  
1318  int cbfs_remove_entry(struct cbfs_image *image, const char *name)
1319  {
1320  	struct cbfs_file *entry;
1321  	entry = cbfs_get_entry(image, name);
1322  	if (!entry) {
1323  		ERROR("CBFS file %s not found.\n", name);
1324  		return -1;
1325  	}
1326  	DEBUG("cbfs_remove_entry: Removed %s @ 0x%x\n",
1327  	      entry->filename, cbfs_get_entry_addr(image, entry));
1328  	entry->type = htobe32(CBFS_TYPE_DELETED);
1329  	cbfs_legacy_walk(image, cbfs_merge_empty_entry, NULL);
1330  	return 0;
1331  }
1332  
1333  int cbfs_print_header_info(struct cbfs_image *image)
1334  {
1335  	char *name = strdup(image->buffer.name);
1336  	assert(image);
1337  	printf("%s: %zd kB, bootblocksize %d, romsize %d, offset 0x%x\n"
1338  	       "alignment: %d bytes, architecture: %s\n\n",
1339  	       basename(name),
1340  	       image->buffer.size / 1024,
1341  	       image->header.bootblocksize,
1342  	       image->header.romsize,
1343  	       image->header.offset,
1344  	       image->header.align,
1345  	       arch_to_string(image->header.architecture));
1346  	free(name);
1347  	return 0;
1348  }
1349  
1350  static int cbfs_print_stage_info(struct cbfs_file *entry, FILE* fp)
1351  {
1352  
1353  	struct cbfs_file_attr_stageheader *stage = NULL;
1354  	for (struct cbfs_file_attribute *attr = cbfs_file_first_attr(entry);
1355  	     attr != NULL; attr = cbfs_file_next_attr(entry, attr)) {
1356  		if (be32toh(attr->tag) == CBFS_FILE_ATTR_TAG_STAGEHEADER) {
1357  			stage = (struct cbfs_file_attr_stageheader *)attr;
1358  			break;
1359  		}
1360  	}
1361  
1362  	if (stage == NULL) {
1363  		fprintf(fp, "    ERROR: stage header not found!\n");
1364  		return -1;
1365  	}
1366  
1367  	fprintf(fp,
1368  		"    entry: 0x%" PRIx64 ", load: 0x%" PRIx64 ", "
1369  		"memlen: %d\n",
1370  		be64toh(stage->loadaddr) + be32toh(stage->entry_offset),
1371  		be64toh(stage->loadaddr),
1372  		be32toh(stage->memlen));
1373  	return 0;
1374  }
1375  
1376  static int cbfs_print_decoded_payload_segment_info(
1377  		struct cbfs_payload_segment *seg, FILE *fp)
1378  {
1379  	/* The input (seg) must be already decoded by
1380  	 * cbfs_decode_payload_segment.
1381  	 */
1382  	switch (seg->type) {
1383  	case PAYLOAD_SEGMENT_CODE:
1384  	case PAYLOAD_SEGMENT_DATA:
1385  		fprintf(fp, "    %s (%s compression, offset: 0x%x, "
1386  			"load: 0x%" PRIx64 ", length: %d/%d)\n",
1387  			(seg->type == PAYLOAD_SEGMENT_CODE ?
1388  			 "code " : "data"),
1389  			lookup_name_by_type(types_cbfs_compression,
1390  					    seg->compression,
1391  					    "(unknown)"),
1392  			seg->offset, seg->load_addr, seg->len,
1393  			seg->mem_len);
1394  		break;
1395  
1396  	case PAYLOAD_SEGMENT_ENTRY:
1397  		fprintf(fp, "    entry (0x%" PRIx64 ")\n",
1398  			seg->load_addr);
1399  		break;
1400  
1401  	case PAYLOAD_SEGMENT_BSS:
1402  		fprintf(fp, "    BSS (address 0x%016" PRIx64 ", "
1403  			"length 0x%x)\n",
1404  			seg->load_addr, seg->len);
1405  		break;
1406  
1407  	case PAYLOAD_SEGMENT_DEPRECATED_PARAMS:
1408  		fprintf(fp, "    parameters (deprecated)\n");
1409  		break;
1410  
1411  	default:
1412  		fprintf(fp, "   0x%x (%s compression, offset: 0x%x, "
1413  			"load: 0x%" PRIx64 ", length: %d/%d\n",
1414  			seg->type,
1415  			lookup_name_by_type(types_cbfs_compression,
1416  					    seg->compression,
1417  					    "(unknown)"),
1418  			seg->offset, seg->load_addr, seg->len,
1419  			seg->mem_len);
1420  		break;
1421  	}
1422  	return 0;
1423  }
1424  
1425  int cbfs_print_entry_info(struct cbfs_image *image, struct cbfs_file *entry,
1426  			  void *arg)
1427  {
1428  	const char *name = entry->filename;
1429  	struct cbfs_payload_segment *payload;
1430  	FILE *fp = (FILE *)arg;
1431  
1432  	if (!cbfs_is_valid_entry(image, entry)) {
1433  		ERROR("cbfs_print_entry_info: Invalid entry at 0x%x\n",
1434  		      cbfs_get_entry_addr(image, entry));
1435  		return -1;
1436  	}
1437  	if (!fp)
1438  		fp = stdout;
1439  
1440  	unsigned int decompressed_size = 0;
1441  	unsigned int compression = cbfs_file_get_compression_info(entry,
1442  		&decompressed_size);
1443  	const char *compression_name = lookup_name_by_type(
1444  			types_cbfs_compression, compression, "????");
1445  
1446  	if (compression == CBFS_COMPRESS_NONE)
1447  		fprintf(fp, "%-30s 0x%-8x %-12s %8d %-4s\n",
1448  			*name ? name : "(empty)",
1449  			cbfs_get_entry_addr(image, entry),
1450  			get_cbfs_entry_type_name(be32toh(entry->type)),
1451  			be32toh(entry->len),
1452  			compression_name
1453  			);
1454  	else
1455  		fprintf(fp, "%-30s 0x%-8x %-12s %8d %-4s (%d decompressed)\n",
1456  			*name ? name : "(empty)",
1457  			cbfs_get_entry_addr(image, entry),
1458  			get_cbfs_entry_type_name(be32toh(entry->type)),
1459  			be32toh(entry->len),
1460  			compression_name,
1461  			decompressed_size
1462  			);
1463  
1464  	if (!verbose)
1465  		return 0;
1466  
1467  	struct cbfs_file_attr_hash *attr = NULL;
1468  	while ((attr = cbfs_file_get_next_hash(entry, attr)) != NULL) {
1469  		size_t hash_len = vb2_digest_size(attr->hash.algo);
1470  		if (!hash_len) {
1471  			fprintf(fp, "invalid/unsupported hash algorithm: %d\n",
1472  				attr->hash.algo);
1473  			break;
1474  		}
1475  		char *hash_str = bintohex(attr->hash.raw, hash_len);
1476  		int valid = vb2_hash_verify(false, CBFS_SUBHEADER(entry),
1477  			be32toh(entry->len), &attr->hash) == VB2_SUCCESS;
1478  		const char *valid_str = valid ? "valid" : "invalid";
1479  
1480  		fprintf(fp, "    hash %s:%s %s\n",
1481  			vb2_get_hash_algorithm_name(attr->hash.algo),
1482  			hash_str, valid_str);
1483  		free(hash_str);
1484  	}
1485  
1486  	DEBUG(" cbfs_file=0x%x, offset=0x%x, content_address=0x%x+0x%x\n",
1487  	      cbfs_get_entry_addr(image, entry), be32toh(entry->offset),
1488  	      cbfs_get_entry_addr(image, entry) + be32toh(entry->offset),
1489  	      be32toh(entry->len));
1490  
1491  	/* note the components of the subheader may be in host order ... */
1492  	switch (be32toh(entry->type)) {
1493  	case CBFS_TYPE_STAGE:
1494  		cbfs_print_stage_info(entry, fp);
1495  		break;
1496  
1497  	case CBFS_TYPE_SELF:
1498  		payload = (struct cbfs_payload_segment *)
1499  				CBFS_SUBHEADER(entry);
1500  		while (payload) {
1501  			struct cbfs_payload_segment seg;
1502  			cbfs_decode_payload_segment(&seg, payload);
1503  			cbfs_print_decoded_payload_segment_info(
1504  					&seg, fp);
1505  			if (seg.type == PAYLOAD_SEGMENT_ENTRY)
1506  				break;
1507  			else
1508  			payload ++;
1509  		}
1510  		break;
1511  	default:
1512  		break;
1513  	}
1514  	return 0;
1515  }
1516  
1517  /*
1518   * The format of this output has been stable for many years. Since it is meant
1519   * to be parsed by scripts, we should probably not lightly make changes to it as
1520   * that could break older scripts expecting a different format.
1521   *
1522   * Until CB:41119, the `-v` flag made no difference when `-k` was selected, so
1523   * presumably no scripts were using that combination. That's why that patch left
1524   * the output for `-k` by itself alone to avoid breaking legacy scripts, and
1525   * expanded `-k -v` to allow an arbitrary number of `<key>:<value>` tokens at
1526   * the end of each row behind the legacy column output. So the new output format
1527   * stability rules should be that `-k` will stay as it is, and `-k -v` may be
1528   * expanded to add more `<key>:<value>` tokens to the end of a row. Scripts that
1529   * want to parse `-k -v` output should be written to gracefully ignore any extra
1530   * such tokens where they don't recognize the key.
1531   *
1532   * The `-k -v` output may also include extra rows that start with a `[`. These
1533   * do not represent a CBFS file and can instead be used to display data that is
1534   * associated with the CBFS as a whole and not any single file. Currently
1535   * defined are `[FMAP REGION]\t<region name>` and
1536   * `[METADATA HASH]\t<hash>:<algo>`. More may be defined in the future and
1537   * scripts parsing `-k -v` output should be written to gracefully ignore any
1538   * rows starting with `[` that they don't recognize.
1539   *
1540   * The format for existing `<key:value>` tokens or `[` rows should never be
1541   * changed once they are added.
1542   */
1543  static int cbfs_print_parseable_entry_info(struct cbfs_image *image,
1544  					struct cbfs_file *entry, void *arg)
1545  {
1546  	FILE *fp = (FILE *)arg;
1547  	const char *name;
1548  	const char *type;
1549  	size_t offset;
1550  	size_t metadata_size;
1551  	size_t data_size;
1552  	const char *sep = "\t";
1553  
1554  	if (!cbfs_is_valid_entry(image, entry)) {
1555  		ERROR("cbfs_print_entry_info: Invalid entry at 0x%x\n",
1556  		      cbfs_get_entry_addr(image, entry));
1557  		return -1;
1558  	}
1559  
1560  	name = entry->filename;
1561  	if (*name == '\0')
1562  		name = "(empty)";
1563  	type = get_cbfs_entry_type_name(be32toh(entry->type)),
1564  	metadata_size = be32toh(entry->offset);
1565  	data_size = be32toh(entry->len);
1566  	offset = cbfs_get_entry_addr(image, entry);
1567  
1568  	fprintf(fp, "%s%s", name, sep);
1569  	fprintf(fp, "0x%zx%s", offset, sep);
1570  	fprintf(fp, "%s%s", type, sep);
1571  	fprintf(fp, "0x%zx%s", metadata_size, sep);
1572  	fprintf(fp, "0x%zx%s", data_size, sep);
1573  	fprintf(fp, "0x%zx", metadata_size + data_size);
1574  
1575  	if (verbose) {
1576  		unsigned int decompressed_size = 0;
1577  		unsigned int compression = cbfs_file_get_compression_info(entry,
1578  			&decompressed_size);
1579  		if (compression != CBFS_COMPRESS_NONE)
1580  			fprintf(fp, "%scomp:%s:0x%x", sep, lookup_name_by_type(
1581  				types_cbfs_compression, compression, "????"),
1582  				decompressed_size);
1583  
1584  		struct cbfs_file_attr_hash *attr = NULL;
1585  		while ((attr = cbfs_file_get_next_hash(entry, attr)) != NULL) {
1586  			size_t hash_len = vb2_digest_size(attr->hash.algo);
1587  			if (!hash_len)
1588  				continue;
1589  			char *hash_str = bintohex(attr->hash.raw, hash_len);
1590  			int valid = vb2_hash_verify(false, CBFS_SUBHEADER(entry),
1591  				be32toh(entry->len), &attr->hash) == VB2_SUCCESS;
1592  			fprintf(fp, "%shash:%s:%s:%s", sep,
1593  				vb2_get_hash_algorithm_name(attr->hash.algo),
1594  				hash_str, valid ? "valid" : "invalid");
1595  			free(hash_str);
1596  		}
1597  	}
1598  	fprintf(fp, "\n");
1599  
1600  	return 0;
1601  }
1602  
1603  void cbfs_print_directory(struct cbfs_image *image)
1604  {
1605  	if (cbfs_is_legacy_cbfs(image))
1606  		cbfs_print_header_info(image);
1607  	printf("%-30s %-10s %-12s   Size   Comp\n", "Name", "Offset", "Type");
1608  	cbfs_legacy_walk(image, cbfs_print_entry_info, NULL);
1609  }
1610  
1611  void cbfs_print_parseable_directory(struct cbfs_image *image)
1612  {
1613  	size_t i;
1614  	const char *header[] = {
1615  		"Name",
1616  		"Offset",
1617  		"Type",
1618  		"Metadata Size",
1619  		"Data Size",
1620  		"Total Size",
1621  	};
1622  	const char *sep = "\t";
1623  
1624  	for (i = 0; i < ARRAY_SIZE(header) - 1; i++)
1625  		fprintf(stdout, "%s%s", header[i], sep);
1626  	fprintf(stdout, "%s\n", header[i]);
1627  	cbfs_legacy_walk(image, cbfs_print_parseable_entry_info, stdout);
1628  }
1629  
1630  int cbfs_merge_empty_entry(struct cbfs_image *image, struct cbfs_file *entry,
1631  			   unused void *arg)
1632  {
1633  	struct cbfs_file *next;
1634  	uint32_t next_addr = 0;
1635  
1636  	/* We don't return here even if this entry is already empty because we
1637  	   want to merge the empty entries following after it. */
1638  
1639  	/* Loop until non-empty entry is found, starting from the current entry.
1640  	   After the loop, next_addr points to the next non-empty entry. */
1641  	next = entry;
1642  	while (be32toh(next->type) == CBFS_TYPE_DELETED ||
1643  			be32toh(next->type) == CBFS_TYPE_NULL) {
1644  		next = cbfs_find_next_entry(image, next);
1645  		if (!next)
1646  			break;
1647  		next_addr = cbfs_get_entry_addr(image, next);
1648  		if (!cbfs_is_valid_entry(image, next))
1649  			/* 'next' could be the end of cbfs */
1650  			break;
1651  	}
1652  
1653  	if (!next_addr)
1654  		/* Nothing to empty */
1655  		return 0;
1656  
1657  	/* We can return here if we find only a single empty entry.
1658  	   For simplicity, we just proceed (and make it empty again). */
1659  
1660  	/* We're creating one empty entry for combined empty spaces */
1661  	uint32_t addr = cbfs_get_entry_addr(image, entry);
1662  	size_t len = next_addr - addr - cbfs_calculate_file_header_size("");
1663  	DEBUG("join_empty_entry: [0x%x, 0x%x) len=%zu\n", addr, next_addr, len);
1664  	return cbfs_create_empty_entry(entry, CBFS_TYPE_NULL, len, "");
1665  }
1666  
1667  int cbfs_legacy_walk(struct cbfs_image *image, cbfs_entry_callback callback,
1668  	      void *arg)
1669  {
1670  	int count = 0;
1671  	struct cbfs_file *entry;
1672  	for (entry = cbfs_find_first_entry(image);
1673  	     entry && cbfs_is_valid_entry(image, entry);
1674  	     entry = cbfs_find_next_entry(image, entry)) {
1675  		count ++;
1676  		if (callback(image, entry, arg) != 0)
1677  			break;
1678  	}
1679  	return count;
1680  }
1681  
1682  static int cbfs_header_valid(struct cbfs_header *header)
1683  {
1684  	if ((be32toh(header->magic) == CBFS_HEADER_MAGIC) &&
1685  	    ((be32toh(header->version) == CBFS_HEADER_VERSION1) ||
1686  	     (be32toh(header->version) == CBFS_HEADER_VERSION2)) &&
1687  	    (be32toh(header->offset) < be32toh(header->romsize)))
1688  		return 1;
1689  	return 0;
1690  }
1691  
1692  struct cbfs_header *cbfs_find_header(char *data, size_t size,
1693  				     uint32_t forced_offset)
1694  {
1695  	size_t offset;
1696  	int found = 0;
1697  	int32_t rel_offset;
1698  	struct cbfs_header *header, *result = NULL;
1699  
1700  	if (forced_offset < (size - sizeof(struct cbfs_header))) {
1701  		/* Check if the forced header is valid. */
1702  		header = (struct cbfs_header *)(data + forced_offset);
1703  		if (cbfs_header_valid(header))
1704  			return header;
1705  		return NULL;
1706  	}
1707  
1708  	// Try finding relative offset of master header at end of file first.
1709  	rel_offset = *(int32_t *)(data + size - sizeof(int32_t));
1710  	offset = size + rel_offset;
1711  	DEBUG("relative offset: %#zx(-%#zx), offset: %#zx\n",
1712  	      (size_t)rel_offset, (size_t)-rel_offset, offset);
1713  
1714  	if (offset >= size - sizeof(*header) ||
1715  	    !cbfs_header_valid((struct cbfs_header *)(data + offset))) {
1716  		// Some use cases append non-CBFS data to the end of the ROM.
1717  		DEBUG("relative offset seems wrong, scanning whole image...\n");
1718  		offset = 0;
1719  	}
1720  
1721  	for (; offset + sizeof(*header) < size; offset++) {
1722  		header = (struct cbfs_header *)(data + offset);
1723  		if (!cbfs_header_valid(header))
1724  			continue;
1725  		if (!found++)
1726  			result = header;
1727  	}
1728  	if (found > 1)
1729  		// Top-aligned images usually have a working relative offset
1730  		// field, so this is more likely to happen on bottom-aligned
1731  		// ones (where the first header is the "outermost" one)
1732  		WARN("Multiple (%d) CBFS headers found, using the first one.\n",
1733  		       found);
1734  	return result;
1735  }
1736  
1737  
1738  struct cbfs_file *cbfs_find_first_entry(struct cbfs_image *image)
1739  {
1740  	assert(image);
1741  	if (image->has_header)
1742  		/* header.offset is relative to start of flash, not
1743  		 * start of region, so use it with the full image.
1744  		 */
1745  		return (struct cbfs_file *)
1746  			(buffer_get_original_backing(&image->buffer) +
1747  			image->header.offset);
1748  	else
1749  		return (struct cbfs_file *)buffer_get(&image->buffer);
1750  }
1751  
1752  struct cbfs_file *cbfs_find_next_entry(struct cbfs_image *image,
1753  				       struct cbfs_file *entry)
1754  {
1755  	uint32_t addr = cbfs_get_entry_addr(image, entry);
1756  	int align = image->has_header ? image->header.align : CBFS_ALIGNMENT;
1757  	assert(entry && cbfs_is_valid_entry(image, entry));
1758  	addr += be32toh(entry->offset) + be32toh(entry->len);
1759  	addr = align_up(addr, align);
1760  	return (struct cbfs_file *)(image->buffer.data + addr);
1761  }
1762  
1763  uint32_t cbfs_get_entry_addr(struct cbfs_image *image, struct cbfs_file *entry)
1764  {
1765  	assert(image && image->buffer.data && entry);
1766  	return (int32_t)((char *)entry - image->buffer.data);
1767  }
1768  
1769  int cbfs_is_valid_cbfs(struct cbfs_image *image)
1770  {
1771  	return buffer_check_magic(&image->buffer, CBFS_FILE_MAGIC,
1772  						strlen(CBFS_FILE_MAGIC));
1773  }
1774  
1775  int cbfs_is_legacy_cbfs(struct cbfs_image *image)
1776  {
1777  	return image->has_header;
1778  }
1779  
1780  int cbfs_is_valid_entry(struct cbfs_image *image, struct cbfs_file *entry)
1781  {
1782  	uint32_t offset = cbfs_get_entry_addr(image, entry);
1783  
1784  	if (offset >= image->buffer.size)
1785  		return 0;
1786  
1787  	struct buffer entry_data;
1788  	buffer_clone(&entry_data, &image->buffer);
1789  	buffer_seek(&entry_data, offset);
1790  	return buffer_check_magic(&entry_data, CBFS_FILE_MAGIC,
1791  						strlen(CBFS_FILE_MAGIC));
1792  }
1793  
1794  struct cbfs_file *cbfs_create_file_header(int type,
1795  			    size_t len, const char *name)
1796  {
1797  	size_t header_size = cbfs_calculate_file_header_size(name);
1798  	if (header_size > CBFS_METADATA_MAX_SIZE) {
1799  		ERROR("'%s' name too long to fit in CBFS header\n", name);
1800  		return NULL;
1801  	}
1802  
1803  	struct cbfs_file *entry = malloc(CBFS_METADATA_MAX_SIZE);
1804  	memset(entry, CBFS_CONTENT_DEFAULT_VALUE, CBFS_METADATA_MAX_SIZE);
1805  	memcpy(entry->magic, CBFS_FILE_MAGIC, sizeof(entry->magic));
1806  	entry->type = htobe32(type);
1807  	entry->len = htobe32(len);
1808  	entry->attributes_offset = 0;
1809  	entry->offset = htobe32(header_size);
1810  	memset(entry->filename, 0, be32toh(entry->offset) - sizeof(*entry));
1811  	strcpy(entry->filename, name);
1812  	return entry;
1813  }
1814  
1815  int cbfs_create_empty_entry(struct cbfs_file *entry, int type,
1816  			    size_t len, const char *name)
1817  {
1818  	struct cbfs_file *tmp = cbfs_create_file_header(type, len, name);
1819  	if (!tmp)
1820  		return -1;
1821  
1822  	memcpy(entry, tmp, be32toh(tmp->offset));
1823  	free(tmp);
1824  	memset(CBFS_SUBHEADER(entry), CBFS_CONTENT_DEFAULT_VALUE, len);
1825  	return 0;
1826  }
1827  
1828  struct cbfs_file_attribute *cbfs_file_first_attr(struct cbfs_file *file)
1829  {
1830  	/* attributes_offset should be 0 when there is no attribute, but all
1831  	 * values that point into the cbfs_file header are invalid, too. */
1832  	if (be32toh(file->attributes_offset) <= sizeof(*file))
1833  		return NULL;
1834  
1835  	/* There needs to be enough space for the file header and one
1836  	 * attribute header for this to make sense. */
1837  	if (be32toh(file->offset) <=
1838  		sizeof(*file) + sizeof(struct cbfs_file_attribute))
1839  		return NULL;
1840  
1841  	return (struct cbfs_file_attribute *)
1842  		(((uint8_t *)file) + be32toh(file->attributes_offset));
1843  }
1844  
1845  struct cbfs_file_attribute *cbfs_file_next_attr(struct cbfs_file *file,
1846  	struct cbfs_file_attribute *attr)
1847  {
1848  	/* ex falso sequitur quodlibet */
1849  	if (attr == NULL)
1850  		return NULL;
1851  
1852  	/* Is there enough space for another attribute? */
1853  	if ((uint8_t *)attr + be32toh(attr->len) +
1854  		sizeof(struct cbfs_file_attribute) >
1855  		(uint8_t *)file + be32toh(file->offset))
1856  		return NULL;
1857  
1858  	struct cbfs_file_attribute *next = (struct cbfs_file_attribute *)
1859  		(((uint8_t *)attr) + be32toh(attr->len));
1860  	/* If any, "unused" attributes must come last. */
1861  	if (be32toh(next->tag) == CBFS_FILE_ATTR_TAG_UNUSED)
1862  		return NULL;
1863  	if (be32toh(next->tag) == CBFS_FILE_ATTR_TAG_UNUSED2)
1864  		return NULL;
1865  
1866  	return next;
1867  }
1868  
1869  struct cbfs_file_attribute *cbfs_add_file_attr(struct cbfs_file *header,
1870  					       uint32_t tag,
1871  					       uint32_t size)
1872  {
1873  	assert(IS_ALIGNED(size, CBFS_ATTRIBUTE_ALIGN));
1874  	struct cbfs_file_attribute *attr, *next;
1875  	next = cbfs_file_first_attr(header);
1876  	do {
1877  		attr = next;
1878  		next = cbfs_file_next_attr(header, attr);
1879  	} while (next != NULL);
1880  	uint32_t header_size = be32toh(header->offset) + size;
1881  	if (header_size > CBFS_METADATA_MAX_SIZE) {
1882  		DEBUG("exceeding allocated space for cbfs_file headers");
1883  		return NULL;
1884  	}
1885  	/* attr points to the last valid attribute now.
1886  	 * If NULL, we have to create the first one. */
1887  	if (attr == NULL) {
1888  		/* New attributes start where the header ends.
1889  		 * header->offset is later set to accommodate the
1890  		 * additional structure.
1891  		 * No endianness translation necessary here, because both
1892  		 * fields are encoded the same way. */
1893  		header->attributes_offset = header->offset;
1894  		attr = (struct cbfs_file_attribute *)
1895  			(((uint8_t *)header) +
1896  			be32toh(header->attributes_offset));
1897  	} else {
1898  		attr = (struct cbfs_file_attribute *)
1899  			(((uint8_t *)attr) +
1900  			be32toh(attr->len));
1901  	}
1902  	header->offset = htobe32(header_size);
1903  	/* Attributes are expected to be small (much smaller than a flash page)
1904  	   and not really meant to be overwritten in-place. To avoid surprising
1905  	   values in reserved fields of attribute structures, initialize them to
1906  	   0, not 0xff. */
1907  	memset(attr, 0, size);
1908  	attr->tag = htobe32(tag);
1909  	attr->len = htobe32(size);
1910  	return attr;
1911  }
1912  
1913  int cbfs_add_file_hash(struct cbfs_file *header, struct buffer *buffer,
1914  	enum vb2_hash_algorithm alg)
1915  {
1916  	if (!vb2_digest_size(alg))
1917  		return -1;
1918  
1919  	struct cbfs_file_attr_hash *attr =
1920  		(struct cbfs_file_attr_hash *)cbfs_add_file_attr(header,
1921  			CBFS_FILE_ATTR_TAG_HASH, cbfs_file_attr_hash_size(alg));
1922  
1923  	if (attr == NULL)
1924  		return -1;
1925  
1926  	if (vb2_hash_calculate(false, buffer_get(buffer), buffer_size(buffer),
1927  			       alg, &attr->hash) != VB2_SUCCESS)
1928  		return -1;
1929  
1930  	return 0;
1931  }
1932  
1933  /* Finds a place to hold whole data in same memory page. */
1934  static int is_in_same_page(uint32_t start, uint32_t size, uint32_t page)
1935  {
1936  	if (!page)
1937  		return 1;
1938  	return (start / page) == (start + size - 1) / page;
1939  }
1940  
1941  /* Tests if data can fit in a range by given offset:
1942   *  start ->| metadata_size | offset (+ size) |<- end
1943   */
1944  static int is_in_range(size_t start, size_t end, size_t metadata_size,
1945  		       size_t offset, size_t size)
1946  {
1947  	return (offset >= start + metadata_size && offset + size <= end);
1948  }
1949  
1950  static size_t absolute_align(const struct cbfs_image *image, size_t val,
1951  				size_t align)
1952  {
1953  	const size_t region_offset = buffer_offset(&image->buffer);
1954  	/* To perform alignment on absolute address, take the region offset */
1955  	/* of the image into account.					    */
1956  	return align_up(val + region_offset, align) - region_offset;
1957  
1958  }
1959  
1960  int32_t cbfs_locate_entry(struct cbfs_image *image, size_t size,
1961  			  size_t page_size, size_t align, size_t metadata_size)
1962  {
1963  	struct cbfs_file *entry;
1964  	size_t need_len;
1965  	size_t addr, addr_next, addr2, addr3, offset;
1966  
1967  	/* Default values: allow fitting anywhere in ROM. */
1968  	if (!page_size)
1969  		page_size = image->has_header ? image->header.romsize :
1970  							image->buffer.size;
1971  	if (!align)
1972  		align = 1;
1973  
1974  	if (size > page_size)
1975  		ERROR("Input file size (%zd) greater than page size (%zd).\n",
1976  		      size, page_size);
1977  
1978  	size_t image_align = image->has_header ? image->header.align :
1979  							CBFS_ALIGNMENT;
1980  	if (page_size % image_align)
1981  		WARN("%s: Page size (%#zx) not aligned with CBFS image (%#zx).\n",
1982  		     __func__, page_size, image_align);
1983  
1984  	need_len = metadata_size + size;
1985  
1986  	// Merge empty entries to build get max available space.
1987  	cbfs_legacy_walk(image, cbfs_merge_empty_entry, NULL);
1988  
1989  	/* Three cases of content location on memory page:
1990  	 * case 1.
1991  	 *          |  PAGE 1  |   PAGE 2  |
1992  	 *          |     <header><content>| Fit. Return start of content.
1993  	 *
1994  	 * case 2.
1995  	 *          |  PAGE 1  |   PAGE 2  |
1996  	 *          | <header><content>    | Fits when we shift content to align
1997  	 *  shift-> |  <header>|<content>  | at starting of PAGE 2.
1998  	 *
1999  	 * case 3. (large content filling whole page)
2000  	 *  | PAGE 1 |  PAGE 2  | PAGE 3 |
2001  	 *  |  <header>< content >       | Can't fit. If we shift content to
2002  	 *  |trial-> <header>< content > | PAGE 2, header can't fit in free
2003  	 *  |  shift->  <header><content> space, so we must use PAGE 3.
2004  	 *
2005  	 * The returned address can be then used as "base-address" (-b) in add-*
2006  	 * commands (will be re-calculated and positioned by cbfs_add_entry_at).
2007  	 * For stage targets, the address is also used to re-link stage before
2008  	 * being added into CBFS.
2009  	 */
2010  	for (entry = cbfs_find_first_entry(image);
2011  	     entry && cbfs_is_valid_entry(image, entry);
2012  	     entry = cbfs_find_next_entry(image, entry)) {
2013  
2014  		uint32_t type = be32toh(entry->type);
2015  		if (type != CBFS_TYPE_NULL)
2016  			continue;
2017  
2018  		addr = cbfs_get_entry_addr(image, entry);
2019  		addr_next = cbfs_get_entry_addr(image, cbfs_find_next_entry(
2020  				image, entry));
2021  		if (addr_next - addr < need_len)
2022  			continue;
2023  
2024  		offset = absolute_align(image, addr + metadata_size, align);
2025  		if (is_in_same_page(offset, size, page_size) &&
2026  		    is_in_range(addr, addr_next, metadata_size, offset, size)) {
2027  			DEBUG("cbfs_locate_entry: FIT (PAGE1).");
2028  			return offset;
2029  		}
2030  
2031  		addr2 = align_up(addr, page_size);
2032  		offset = absolute_align(image, addr2, align);
2033  		if (is_in_range(addr, addr_next, metadata_size, offset, size)) {
2034  			DEBUG("cbfs_locate_entry: OVERLAP (PAGE2).");
2035  			return offset;
2036  		}
2037  
2038  		/* Assume page_size >= metadata_size so adding one page will
2039  		 * definitely provide the space for header. */
2040  		assert(page_size >= metadata_size);
2041  		addr3 = addr2 + page_size;
2042  		offset = absolute_align(image, addr3, align);
2043  		if (is_in_range(addr, addr_next, metadata_size, offset, size)) {
2044  			DEBUG("cbfs_locate_entry: OVERLAP+ (PAGE3).");
2045  			return offset;
2046  		}
2047  	}
2048  	return -1;
2049  }