starred/openwrt-docker
1
0
Fork 0
mirror of https://github.com/AlbrechtL/openwrt-docker.git synced 2026-10-14 08:01:25 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add option "-o, --offsets Give offsets (comma-separated <squashfs>,<ext4 or f2fs>)"

Browse Source
This commit is contained in:
Albrecht Lohofener
2024-11-16 21:41:48 +01:00
parent 3f5b98a011
commit 6b817060d9
1 changed files with 27 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/mount_openwrt_squashfs_combined.sh
+27 -10
View File
@@ -32,6 +32,7 @@ show_help() {
echo
echo "Options:"
echo " -u, --umount Unmounts a previous mounted image"
echo " -o, --offsets Give offsets (comma-separated <squashfs>,<ext4 or f2fs>)"
echo " -h, --help Display this help message"
echo
echo "Example:"
@@ -52,7 +53,7 @@ find_squashfs_offset() {
local squashfs_offset=$(( squashfs_start_sectors * 512 )) # Each sector has 512 bytes
echo >&2 "squashfs file system start at offset 0x$(printf '%x' "$squashfs_offset")"
echo >&2 "squashfs file system start at offset 0x$(printf '%x' "$squashfs_offset") ($squashfs_offset)"
echo $squashfs_offset
}
@@ -75,7 +76,7 @@ find_ext4_offset() {
fi
# Output OFFSET in hexadecimal format
echo >&2 "Found volume name '$ROOTFS_PATTERN' at offset: 0x$(printf '%x' "$OFFSET")"
echo >&2 "Found volume name '$ROOTFS_PATTERN' at offset: 0x$(printf '%x' "$OFFSET") ($OFFSET)"
# Step 2: Use dd to extract the bytes and search for the EXT4_MAGIC_KEY
# Extract the byte offset from the grep result (this is relative to the start of the dd block)
@@ -92,8 +93,8 @@ find_ext4_offset() {
# Show the adjusted actual_offset
#echo >&2 "Offset in dd block: 0x$(printf '%x' "$offset_in_block")"
echo >&2 "Found ext4 magic key '$EXT4_MAGIC_KEY' at offset: 0x$(printf '%x' "$actual_offset")"
echo >&2 "ext4 file system start at offset: 0x$(printf '%x' "$ext4_start_offset")"
echo >&2 "Found ext4 magic key '$EXT4_MAGIC_KEY' at offset: 0x$(printf '%x' "$actual_offset") ($actual_offset)"
echo >&2 "ext4 file system start at offset: 0x$(printf '%x' "$ext4_start_offset") ($ext4_start_offset)"
echo $ext4_start_offset
}
@@ -102,7 +103,6 @@ find_ext4_offset() {
find_f2fs_offset() {
local IMAGE_FILE="$1"
local SQUASHFS_OFFSET="$2"
echo >&2 "Start finding start of j2fs file system in file '$IMAGE_FILE' ..."
# Define the search boundary (in bytes)
local SQUASHFS_SIZE_APPROX=4000000 # This is the size assumtion of squashfs file system that is located before the j2fs
@@ -119,8 +119,8 @@ find_f2fs_offset() {
local actual_offset=$((offset_in_block + SQUASHFS_OFFSET + SQUASHFS_SIZE_APPROX)) # Adjust the offset to the actual position in the original file
local j2fs_start_offset=$((actual_offset - 1024)) # Subtract 1024 bytes from the found offset. j2fs is starting 1024 before 0x1020f5f2
echo >&2 "Found j2fs magic key '$J2FS_MAGIC_KEY' at offset: 0x$(printf '%x' "$actual_offset")"
echo >&2 "j2fs file system start at offset: 0x$(printf '%x' "$j2fs_start_offset")"
echo >&2 "Found j2fs magic key '$J2FS_MAGIC_KEY' at offset: 0x$(printf '%x' "$actual_offset") ($actual_offset)"
echo >&2 "j2fs file system start at offset: 0x$(printf '%x' "$j2fs_start_offset") ($j2fs_start_offset)"
echo $j2fs_start_offset
}
@@ -140,12 +140,29 @@ if [[ "$1" == "-h" || "$1" == "--help" ]]; then
exit 0
fi
# Check for help option
# Check for umount option
if [[ "$1" == "-u" || "$1" == "--umount" ]]; then
umount_squashfs_combined_image
exit 0
fi
# Check for give offsets option
if [[ "$1" == "-o" || "$1" == "--offsets" ]]; then
IMAGE_FILE="$2"
CPU_ARCH="$3"
squashfs_start_offset=$(find_squashfs_offset "$IMAGE_FILE")
if [ $CPU_ARCH = "aarch64" ]; then
start_offset=$(find_f2fs_offset "$IMAGE_FILE" "$squashfs_start_offset")
else
start_offset=$(find_ext4_offset "$IMAGE_FILE")
fi
echo "$squashfs_start_offset,$start_offset"
exit 0
fi
# Check for the correct number of arguments
if [[ $# -ne 2 ]]; then
echo "Error: Exactly two arguments are required."
@@ -164,9 +181,9 @@ echo >&2 "Start finding file system offsets in file '"$IMAGE_FILE"' ..."
squashfs_start_offset=$(find_squashfs_offset "$IMAGE_FILE")
if [ $CPU_ARCH = "aarch64" ]; then
start_offset=$(find_f2fs_offset "$IMAGE_FILE" "$squashfs_start_offset")
start_offset=$(find_f2fs_offset "$IMAGE_FILE" "$squashfs_start_offset")
else
start_offset=$(find_ext4_offset "$IMAGE_FILE")
start_offset=$(find_ext4_offset "$IMAGE_FILE")
fi
mkdir -p /tmp/squashfs_dir