starred/openwrt-docker
1
0
Fork 0
mirror of https://github.com/AlbrechtL/openwrt-docker.git synced 2026-10-14 00:01:26 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add j2fs file system detection

Browse Source
This commit is contained in:
Albrecht Lohofener
2024-11-13 00:51:59 +01:00
parent 0a740859f6
commit 6ceb88ef2a
2 changed files with 42 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Dockerfile
+1
View File
@@ -67,6 +67,7 @@ RUN echo "Building for platform '$TARGETPLATFORM'" \
uuidgen \
usbutils \
openssh-client \
util-linux-misc \
&& mkdir -p /usr/share/novnc \
&& wget https://github.com/novnc/noVNC/archive/refs/tags/v${NOVNC_VERSION}.tar.gz -O /tmp/novnc.tar.gz -q \
&& tar -xf /tmp/novnc.tar.gz -C /tmp/ \
src/migrate_openwrt_rootfs.sh
+41 -9
View File
@@ -12,7 +12,7 @@ find_squashfs_offset() {
echo >&2 "Start finding start of squashfs file system in file '"$IMAGE_FILE"' ..."
# Use fdisk to find the squashfs partition
local squashfs_start_sectors=`fdisk -l "$IMAGE_FILE" | awk '/^.*squashfs-combined.*.img2/ {print $4}'` # use the 4th ouput as sectors
local squashfs_start_sectors=`fdisk -l "$IMAGE_FILE" | awk '/^.*squashfs-combined.*.img2/ {print $2}'` # use the 4th ouput as sectors
if [ -z "$squashfs_start_sectors" ]; then
echo >&2 "No squashfs-combined*.img2 found"
@@ -57,7 +57,7 @@ find_ext4_offset() {
return 1
fi
actual_offset=$((offset_in_block + OFFSET - SEARCH_BOUNDARY)) # Adjust the offset to the actual position in the original file
local actual_offset=$((offset_in_block + OFFSET - SEARCH_BOUNDARY)) # Adjust the offset to the actual position in the original file
local ext4_start_offset=$((actual_offset - 1080)) # Subtract 1080 bytes from the found offset. ext4 is starting 1080 before 0x53ef
# Show the adjusted actual_offset
@@ -68,24 +68,56 @@ find_ext4_offset() {
echo $ext4_start_offset
}
# Function to find the ext4 file system start offset from a OpenWrt given file
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
local J2FS_MAGIC_KEY="\x10\x20\xf5\xf2" # This is the magic key identifying the ext4 file system (as hex string)
local offset_in_block=`dd if="$IMAGE_FILE" bs=1 skip=$((SQUASHFS_OFFSET + SQUASHFS_SIZE_APPROX)) 2>/dev/null | \
LANG=C grep -obUaPm 1 "$J2FS_MAGIC_KEY" | cut -d: -f1`
if [ -z "$offset_in_block" ]; then
echo >&2 "j2fs magic key not found in the file."
return 1
fi
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 $j2fs_start_offset
}
mount_squashfs_combined_image() {
local IMAGE_FILE="$1"
squashfs_start_offset=$(find_squashfs_offset "$IMAGE_FILE")
ext4_start_offset=$(find_ext4_offset "$IMAGE_FILE")
CPU_ARCH=$(arch)
if [ $CPU_ARCH = "aarch64" ]; then
start_offset=$(find_f2fs_offset "$IMAGE_FILE" "$squashfs_start_offset")
else
start_offset=$(find_ext4_offset "$IMAGE_FILE")
fi
mkdir -p /tmp/squashfs_dir
mkdir -p /tmp/ext4_dir
mkdir -p /tmp/userdata_dir
mount -o offset="$squashfs_start_offset" "$IMAGE_FILE" /tmp/squashfs_dir
mount -o offset="$ext4_start_offset" "$IMAGE_FILE" /tmp/ext4_dir
mount -t overlay -o lowerdir=/tmp/squashfs_dir,upperdir=/tmp/ext4_dir/upper,workdir=/tmp/ext4_dir/work overlay /mnt
mount -o offset="$squashfs_start_offset",sizelimit=$((start_offset-squashfs_start_offset)) "$IMAGE_FILE" /tmp/squashfs_dir
mount -o offset="$start_offset" "$IMAGE_FILE" /tmp/userdata_dir
mount -t overlay -o lowerdir=/tmp/squashfs_dir,upperdir=/tmp/userdata_dir/upper,workdir=/tmp/userdata_dir/work overlay /mnt
}
umount_squashfs_combined_image() {
umount /mnt
umount /tmp/ext4_dir
umount /tmp/userdata_dir
umount /tmp/squashfs_dir
}