该仓库包含基于 Kaitai 的、与 MediaTek modem 固件相关的文件格式定义,以及一些用于处理这些文件类型的基本命令行工具。也可以使用 Kaitai IDE 通过 Kaitai 定义(位于 mtk_structs 目录中的 *.ksy 文件)交互式地探索文件。
基于这些定义的 md1img 文件的 Ghidra 加载器可在 https://github.com/nccgroup/ghidra-mtk-loader 获取。
以来自 https://mirrors.lolinet.com/firmware/lenomola/tesla/official/TMO/ 的 XT2205-1_TESLA_TMO_12_S2STS32.71-118-4-2-6-3_subsidy-TMO_UNI_RSU_QCOM_regulatory-DEFAULT_cid50_CFC.xml.zip 为例:
md1img 容器md1_extract.py 提取 md1img 中包含的文件:
$ ./md1_extract.py ../XT2205-1_TESLA_TMO_12_S2STS32.71-118-4-2-6-3_subsidy-TMO_UNI_RSU_QCOM_regulatory-DEFAULT_cid50_CFC/md1img.img --outdir ./md1img_out/
extracting files to: ./md1img_out
md1rom: addr=0x00000000, size=43084864
extracted to 000_md1rom
cert1md: addr=0x12345678, size=1781
extracted to 001_cert1md
cert2: addr=0x12345678, size=988
extracted to 002_cert2
md1drdi: addr=0x00000000, size=12289536
extracted to 003_md1drdi
cert1md: addr=0x12345678, size=1781
extracted to 004_cert1md
cert2: addr=0x12345678, size=988
extracted to 005_cert2
md1dsp: addr=0x00000000, size=6776460
extracted to 006_md1dsp
cert1md: addr=0x12345678, size=1781
extracted to 007_cert1md
cert2: addr=0x12345678, size=988
extracted to 008_cert2
md1_filter: addr=0xffffffff, size=300
extracted to 009_md1_filter
md1_filter_PLS_PS_ONLY: addr=0xffffffff, size=300
extracted to 010_md1_filter_PLS_PS_ONLY
md1_filter_1_Moderate: addr=0xffffffff, size=300
extracted to 011_md1_filter_1_Moderate
md1_filter_2_Standard: addr=0xffffffff, size=300
extracted to 012_md1_filter_2_Standard
md1_filter_3_Slim: addr=0xffffffff, size=300
extracted to 013_md1_filter_3_Slim
md1_filter_4_UltraSlim: addr=0xffffffff, size=300
extracted to 014_md1_filter_4_UltraSlim
md1_filter_LowPowerMonitor: addr=0xffffffff, size=300
extracted to 015_md1_filter_LowPowerMonitor
md1_emfilter: addr=0xffffffff, size=2252
extracted to 016_md1_emfilter
md1_dbginfodsp: addr=0xffffffff, size=1635062
extracted to 017_md1_dbginfodsp
md1_dbginfo: addr=0xffffffff, size=1332720
extracted to 018_md1_dbginfo
md1_mddbmeta: addr=0xffffffff, size=899538
extracted to 019_md1_mddbmeta
md1_mddbmetaodb: addr=0xffffffff, size=562654
extracted to 020_md1_mddbmetaodb
md1_mddb: addr=0xffffffff, size=12280622
extracted to 021_md1_mddb
md1_mdmlayout: addr=0xffffffff, size=8341403
extracted to 022_md1_mdmlayout
md1_file_map: addr=0xffffffff, size=889
extracted to 023_md1_file_map
主 modem 固件位于 md1rom 文件(000_md1rom)中。如需对 nanoMIPS 二进制进行逆向工程,请参阅 nanoMIPS Ghidra 扩展。
mtk_dbg_extract.py 从 md1_dbginfo(完整文件名由 md1_file_map 给出)提取符号,并以文本格式输出,该格式可通过 Ghidra 的 ImportSymbolsScript.py 脚本导入。
$ ./mtk_dbg_extract.py symbols DbgInfo_NR16.R2.MT6879.TC2.PR1.SP_LENOVO_S0MP1_K6879V1_64_MT6879_NR16_TC2_PR1_SP_V17_P38_03_24_03R_2023_05_19_22_31 | tee debug_symbols.txt
INT_Vectors 0x0000084c f
brom_ext_main 0x00000860 f
INT_SetPLL_Gen98 0x00000866 f
PLL_Set_CLK_To_26M 0x000009a2 f
PLL_MD_Pll_Init 0x000009da f
INT_SetPLL 0x000009dc f
INT_Initialize_Phase1 0x027b5c80 f
INT_Initialize_Phase2 0x027b617c f
init_cm 0x027b6384 f
init_cm_wt 0x027b641e f
...
某些调试信息文件(例如示例固件中的 md1_dbginfodsp)包含多个文件的符号。目前,每个文件的符号将按顺序打印,并用以 # 开头的分隔行隔开,例如:
# 0x000010 DSP_USIP0
_ss_reset_entry 0x00000000 l
_vector_excpetion_veneer 0x00000404 l
...
# 0x081c4b DSP_USIP1
_ss_reset_entry 0x00000000 l
_vector_excpetion_veneer 0x00000404 l
...
# 0x2cb407 DSP_SCQ16 SCQ16_LTE_ROCODE
void_lte_dmrs_comm_cell_info_trace___uint___uint 0x0003aff8 l
void_inv_cholesky_4x4_vst_func_Q3_VMLmvpvHalf_Q3_VMLmvpvHalf_Q3_VMLmvpvcHalf_Q3_VMLmvpvcHalf_Q3_VMLmvpvcHalf_Q3_VMLmvpvcHalf_Q3_VMLmvpvcHalf_Q3_VMLmvpvHalf_Q3_VMLmvpvHalf_Q3_VMLmvpvcHalf_Q3_VMLmvpsHalf___uint___uint___uint___uint___uint___uint___uint___uint___uint___uint___uint___uint___uint___uint___uint___uint 0x0004a5ab l
...
ImportSymbolsScript.py 不支持这些注释行,因此必须手动拆分。(TODO:增加为每个条目输出符号文本文件的选项。)