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這個內核鏡像是什麼格式的？無法從中提取內核程式碼？

tag-icon • tag-icon linux-kernel android images
這個內核鏡像是什麼格式的？無法從中提取內核程式碼？

我得到了一個 Android 圖像，其中包含：

-rwxr-xr-x 1 root root  69206016 Dec 16 17:01 cache.img
-rwxr-xr-x 1 root root   6024864 Mar 23  2016 Image
-rwxr-xr-x 1 root root   1108329 Mar  7  2016 ramdisk.img
-rwxr-xr-x 1 root root 943718400 Mar  7  2016 system.img
-rwxr-xr-x 1 root root 576716800 Dec 16 17:02 userdata.img

它可以透過 android 模擬器啟動：

./emulator64-ranchu-arm64 -system ./system.img -data ./userdata.img -ramdisk ./ramdisk.img -kernel ./Image -cache ./cache.img     -sysdir ./ -no-window  -verbose -show-kernel

或直接使用qemu：

./qemu/linux-x86_64/qemu-system-aarch64 -cpu cortex-a57 -machine type=ranchu -m 512 -append 'console=ttyAMA0,38400 keep_bootcon earlyprintk=ttyAMA0' -serial mon:stdio -kernel .//Image -initrd .//ramdisk.img -drive index=0,id=sdcard,file=.//system.img -device virtio-blk-device,drive=sdcard -drive index=1,id=userdata,file=.//.//userdata.img -device virtio-blk-device,drive=userdata -drive index=2,id=cache,file=.//cache.img -device virtio-blk-device,drive=cache -drive index=3,id=system,file=.//system.img -device virtio-blk-device,drive=system -netdev user,id=mynet -device virtio-net-device,netdev=mynet -show-cursor -nographic -L lib/pc-bios

現在我想提取內核程式碼，但這個圖像似乎不同。通常的步驟：找到gzip資料的偏移量，使用 分割它dd，使用gzip取得vmlinux，對其不起作用。以下是從該圖像中獲得的資訊：

root@Debian:~$ file Image
Image: data

root@Debian:~$ binwalk Image

DECIMAL       HEXADECIMAL     DESCRIPTION
--------------------------------------------------------------------------------
4395136       0x431080        Linux kernel version "3.10.0+ (root@jiayy) (gcc version 4.9.x-google 20140827 (prerelease) (GCC) ) #63 SMP PREEMPT Wed Mar 23 11:27:47 CST 2016"
4407688       0x434188        gzip compressed data, maximum compression, from Unix, NULL date (1970-01-01 00:00:00)
5270000       0x5069F0        Unix path: /data2/kernel/goldfish/arch/arm64/include/asm/pgalloc.h
5347656       0x519948        Ubiquiti partition header, header size: 56 bytes, name: "PARTNAME=%s", base address: 0x63697479, data size: 0 bytes
5367856       0x51E830        Unix path: /lib/firmware/updates/3.10.0+
5382775       0x522277        Unix path: /net/ethernet/smsc/smc91x.c
5410863       0x52902F        Unix path: /staging/android/ion/ion.c
5412463       0x52966F        Unix path: /staging/android/ion/ion_heap.c
5412663       0x529737        Unix path: /staging/android/ion/ion_page_pool.c
5412823       0x5297D7        Unix path: /staging/android/ion/ion_system_heap.c
5443853       0x53110D        Copyright string: "Copyright (c) 2006-2007 BalaBit IT Ltd."
5483104       0x53AA60        Neighborly text, "NeighborSolicits"
5483128       0x53AA78        Neighborly text, "NeighborAdvertisementsErrors"
5488754       0x53C072        Neighborly text, "neighbor %.2x%.2x.%pM lost rename link %s to %s"
5710184       0x572168        ASCII cpio archive (SVR4 with no CRC), file name: "dev", file name length: "0x00000004", file size: "0x00000000"
5710300       0x5721DC        ASCII cpio archive (SVR4 with no CRC), file name: "dev/console", file name length: "0x0000000C", file size: "0x00000000"
5710424       0x572258        ASCII cpio archive (SVR4 with no CRC), file name: "root", file name length: "0x00000005", file size: "0x00000000"
5710540       0x5722CC        ASCII cpio archive (SVR4 with no CRC), file name: "TRAILER!!!", file name length: "0x0000000B", file size: "0x00000000"
5754880       0x57D000        ELF, 64-bit LSB shared object, version 1 (SYSV)
5760064       0x57E440        CRC32 polynomial table, little endian


root@Debian:~$ xxd -g 1 Image|head
0000000: 10 00 00 14 00 00 00 00 00 00 08 00 00 00 00 00  ................
0000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
0000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
0000030: 00 00 00 00 00 00 00 00 41 52 4d 64 00 00 00 00  ........ARMd....
0000040: f5 03 00 aa 72 00 00 94 0e 00 00 94 16 00 38 d5  ....r.........8.
0000050: e0 03 16 aa fb 00 00 94 f7 03 00 aa 97 1e 00 b4  ................
0000060: 0a 01 00 94 73 00 00 94 9b 1a 00 58 3e 0b 00 10  ....s......X>...
0000070: ec 0a 40 f9 8c 01 1c 8b 80 01 1f d6 1f 20 03 d5  ..@.......... ..
0000080: 40 42 38 d5 1f 20 00 f1 04 18 49 fa 20 17 00 58  @B8.. ....I. ..X
0000090: 00 00 1c 8b 60 00 00 54 1f 00 00 b9 c0 03 5f d6  ....`..T......_.

可以從偏移量0x434188（對應binwalk輸出中的第二段）提取核心設定檔。我還嘗試使用來自 google git 的 extract-vmlinux.sh(https://android.googlesource.com/kernel/goldfish/+/android-goldfish-3.10-m-dev/scripts/extract-vmlinux）但它也不起作用。

那麼這個核心映像是什麼格式以及如何從中提取核心程式碼呢？

答案1

我知道我來晚了一點，但我只是在處理一個與提問者非常相似的 vmlinux 映像。當您擁有的只是aarch64-linux-gnu-objdump -b binary -maarch64 -EL -D vmlinux.

幸運的是，一些美麗的靈魂編寫了一個工具來將原始 vmlinux 映像轉換為 ELF 二進位格式。該映像不可執行，但可以被偵錯器/反組譯器（例如 gdb 或刀具。它還會嘗試尋找嵌入的符號並在輸出 ELF 檔案中解析它們。可以找到名為 vmlinux-to-elf 的工具這裡

連結：

下載切割機

下載 vmlinux-to-elf

答案2

該核心映像是 vmlinux 的可開機原始二進位檔案部分，這意味著它不是完整的 ELF 檔案。只需從頭開始反彙編即可獲得內核程式碼。

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