cbfstool: add a command to duplicate a cbfs instance

The new command allows to create a file where the original CBFS image
is duplicated at a different offset.

The required options of the new command are -D, the offset where the
copy CBFS header is placed, and -s, the size of the new CBFS copy.

When a CBFS is copied, the bootblock area of the source CBFS is
ignored, as well as empty and deleted files in the source CBFS. The
size of the destination CBFS is calculated as the rombase size of the
source CBFS less the bootblock size.

The copy instance can be created in the image only above the original,
which rules out the use of this new command for x86 images. If
necessary, this limitation could be addressed later.

As with other cbfstool commands, unless explicitly specified the
lowest CBFS instance in the image is considered the source. If
necessary, the user can specify the source CBFS using the -H option.

BRANCH=storm
BUG=chrome-os-partner:34161, chromium:445938
TEST=run multiple cbfstool commands on a storm image:
  $ cd /tmp
  $ cp /build/storm/firmware/image.serial.bin storm.bin
  $ cbfstool storm.bin print
  storm.bin: 8192 kB, bootblocksize 34472, romsize 458752, offset 0x8700
  alignment: 64 bytes, architecture: arm

  Name                           Offset     Type         Size
  cdt.mbn                        0x8700     raw          416
  ddr.mbn                        0x8900     raw          25836
  rpm.mbn                        0xee40     raw          78576
  tz.mbn                         0x22180    raw          85360
  fallback/verstage              0x36f40    stage        41620
  fallback/romstage              0x41240    stage        19556
  fallback/ramstage              0x45f00    stage        25579
  config                         0x4c340    raw          2878
  fallback/payload               0x4cec0    payload      64811
  u-boot.dtb                     0x5cc40    (unknown)    2993
  (empty)                        0x5d840    null         75608
  $ cbfstool storm.bin copy -D 0x420000
  E: You need to specify -s/--size.
  $ cbfstool  storm.bin copy -D 0x420000 -s 0x70000
  $ cbfstool  storm.bin print
  W: Multiple (2) CBFS headers found, using the first one.
  storm.bin: 8192 kB, bootblocksize 34472, romsize 458752, offset 0x8700
  alignment: 64 bytes, architecture: arm

  Name                           Offset     Type         Size
  cdt.mbn                        0x8700     raw          416
  ddr.mbn                        0x8900     raw          25836
  rpm.mbn                        0xee40     raw          78576
  tz.mbn                         0x22180    raw          85360
  fallback/verstage              0x36f40    stage        41620
  fallback/romstage              0x41240    stage        19556
  fallback/ramstage              0x45f00    stage        25579
  config                         0x4c340    raw          2878
  fallback/payload               0x4cec0    payload      64811
  u-boot.dtb                     0x5cc40    (unknown)    2993
  (empty)                        0x5d840    null         75608
  cbfstool  storm.bin print  -H 0x420000
  storm.bin: 8192 kB, bootblocksize 0, romsize 4784128, offset 0x420040
  alignment: 64 bytes, architecture: arm

  Name                           Offset     Type         Size
  cdt.mbn                        0x420040   raw          416
  ddr.mbn                        0x420240   raw          25836
  rpm.mbn                        0x426780   raw          78576
  tz.mbn                         0x439ac0   raw          85360
  fallback/verstage              0x44e880   stage        41620
  fallback/romstage              0x458b80   stage        19556
  fallback/ramstage              0x45d840   stage        25579
  config                         0x463c80   raw          2878
  fallback/payload               0x464800   payload      64811
  u-boot.dtb                     0x474580   (unknown)    2993
  (empty)                        0x475180   null         110168
  $ cbfstool storm.bin remove -n config -H 0x420000
  $ cbfstool  storm.bin copy  -H 0x420000 -D 0x620000 -s 0x70000
  $ cbfstool  storm.bin print -H 0x620000
  storm.bin: 8192 kB, bootblocksize 0, romsize 6881280, offset 0x620040
  alignment: 64 bytes, architecture: arm

  Name                           Offset     Type         Size
  cdt.mbn                        0x620040   raw          416
  ddr.mbn                        0x620240   raw          25836
  rpm.mbn                        0x626780   raw          78576
  tz.mbn                         0x639ac0   raw          85360
  fallback/verstage              0x64e880   stage        41620
  fallback/romstage              0x658b80   stage        19556
  fallback/ramstage              0x65d840   stage        25579
  fallback/payload               0x663c80   payload      64811
  u-boot.dtb                     0x673a00   (unknown)    2993
  (empty)                        0x674600   null         113112

  $ cbfstool /build/storm/firmware/image.serial.bin extract -n fallback/payload -f payload1
  [..]
  $ cbfstool storm.bin extract -H 0x620000  -n fallback/payload -f payload2
  [..]
  $ diff payload1 payload2

Change-Id: Ieb9205848aec361bb870de0d284dff06c597564f
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: b8d3c1b09a47ca24d2d2effc6de0e89d1b0a8903
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Change-Id: I227e607ccf7a9a8e2a1f3c6bbc506b8d29a35b1b
Original-Reviewed-on: https://chromium-review.googlesource.com/237561
Reviewed-on: http://review.coreboot.org/9742
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 82 insertions, 0 deletions

diff --git a/util/cbfstool/cbfs_image.c b/util/cbfstool/cbfs_image.c
index 621a35d16f..9df2030679 100644
--- a/util/cbfstool/cbfs_image.c
+++ b/util/cbfstool/cbfs_image.c
@@ -294,6 +294,88 @@ int cbfs_image_from_file(struct cbfs_image *image,
 	return 0;
 }
 
+int cbfs_copy_instance(struct cbfs_image *image, size_t copy_offset,
+			size_t copy_size)
+{
+	struct cbfs_file *src_entry, *dst_entry;
+	struct cbfs_header *copy_header;
+	size_t align, entry_offset;
+	ssize_t last_entry_size;
+
+	size_t header_offset, header_end;
+	size_t cbfs_offset, cbfs_end;
+	size_t copy_end = copy_offset + copy_size;
+
+	align = htonl(image->header->align);
+
+	header_offset = (char *)image->header - image->buffer.data;
+	header_end = header_offset + sizeof(image->header);
+
+	cbfs_offset = htonl(image->header->offset);
+	cbfs_end = htonl(image->header->romsize);
+
+	if (copy_end > image->buffer.size) {
+		ERROR("Copy offset out of range: [%zx:%zx)\n",
+			copy_offset, copy_end);
+		return 1;
+	}
+
+	/* Range check requested copy region with header and source cbfs. */
+	if ((copy_offset >= header_offset && copy_offset < header_end) ||
+	    (copy_end >= header_offset && copy_end <= header_end)) {
+		ERROR("New image would overlap old header.\n");
+	}
+
+	if ((copy_offset >= cbfs_offset && copy_offset < cbfs_end) ||
+	    (copy_end >= cbfs_offset && copy_end <= cbfs_end)) {
+		ERROR("New image would overlap old one.\n");
+		return 1;
+	}
+
+	/* This will work, let's create a copy. */
+	copy_header = (struct cbfs_header *)(image->buffer.data + copy_offset);
+	*copy_header = *image->header;
+
+	copy_header->bootblocksize = 0;
+	/* Romsize is a misnomer. It's the absolute limit of cbfs content.*/
+	copy_header->romsize = htonl(copy_end);
+	entry_offset = align_up(copy_offset + sizeof(*copy_header), align);
+	copy_header->offset = htonl(entry_offset);
+	dst_entry = (struct cbfs_file *)(image->buffer.data + entry_offset);
+
+	/* Copy non-empty files */
+	for (src_entry = cbfs_find_first_entry(image);
+	     src_entry && cbfs_is_valid_entry(image, src_entry);
+	     src_entry = cbfs_find_next_entry(image, src_entry)) {
+		size_t entry_size;
+
+		if ((src_entry->type == htonl(CBFS_COMPONENT_NULL)) ||
+		    (src_entry->type == htonl(CBFS_COMPONENT_DELETED)))
+			continue;
+
+		entry_size = htonl(src_entry->len) + htonl(src_entry->offset);
+		memcpy(dst_entry, src_entry, entry_size);
+		dst_entry = (struct cbfs_file *)(
+			(uintptr_t)dst_entry + align_up(entry_size, align));
+
+		if (((char *)dst_entry - image->buffer.data) >= copy_end) {
+			ERROR("Ran out of room in copy region.\n");
+			return 1;
+		}
+	}
+
+	/* Last entry size is all the room above it. */
+	last_entry_size = copy_end - ((char *)dst_entry - image->buffer.data)
+		- cbfs_calculate_file_header_size("");
+
+	if (last_entry_size < 0)
+		WARN("No room to create the last entry!\n")
+	else
+		cbfs_create_empty_entry(image, dst_entry, last_entry_size, "");
+
+	return 0;
+}
+
 int cbfs_image_write_file(struct cbfs_image *image, const char *filename)
 {
 	assert(image && image->buffer.data);