Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Added support for Autel encoded firmware #712

Merged
merged 1 commit into from
Oct 25, 2024
Merged

Added support for Autel encoded firmware #712

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 1 addition & 0 deletions src/extractors.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -141,6 +141,7 @@

pub mod androidsparse;
pub mod arcadyan;
pub mod autel;
pub mod bzip2;
pub mod cab;
pub mod common;
Expand Down
340 changes: 340 additions & 0 deletions src/extractors/autel.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,340 @@
use crate::extractors::common::{Chroot, ExtractionResult, Extractor, ExtractorType};
use crate::structures::autel::parse_autel_header;

const BLOCK_SIZE: usize = 256;

/// Defines the internal extractor function for deobfuscating Autel firmware
pub fn autel_extractor() -> Extractor {
Extractor {
utility: ExtractorType::Internal(autel_deobfuscate),
..Default::default()
}
}

/// Internal extractor for obfuscated Autel firmware
/// https://gist.github.com/sector7-nl/3fc815cd2497817ad461bfbd393294cb
pub fn autel_deobfuscate(
file_data: &[u8],
offset: usize,
output_directory: Option<&String>,
) -> ExtractionResult {
const OUTPUT_FILE_NAME: &str = "autel.decoded";

let mut result = ExtractionResult {
..Default::default()
};

// Parse and validate the header
if let Ok(autel_header) = parse_autel_header(&file_data[offset..]) {
// Get the start and end offsets of the actual encoded data
let data_start = offset + autel_header.header_size;
let data_end = data_start + autel_header.data_size;

// Get the encoded data
if let Some(autel_data) = file_data.get(data_start..data_end) {
// Interate through each block of the encoded data
let mut block_iter = autel_data.chunks(BLOCK_SIZE);

loop {
match block_iter.next() {
None => {
// EOF
result.size = Some(autel_header.data_size);
result.success = true;
break;
}
Some(block_bytes) => {
// Decode the data block
let decoded_block = decode_autel_block(block_bytes);

// Write to file, if requested
if output_directory.is_some() {
let chroot = Chroot::new(output_directory);
if !chroot.append_to_file(OUTPUT_FILE_NAME, &decoded_block) {
break;
}
}
}
}
}
}
}

result
}

/// Block decoder for autel encoded firmware.
/// block_data *must* be 256 bytes in size, or less.
fn decode_autel_block(block_data: &[u8]) -> Vec<u8> {
// Lookup table for encoding/decoding bytes
let encoding_table: Vec<(usize, usize)> = vec![
(54, 147),
(96, 129),
(59, 193),
(191, 0),
(45, 130),
(96, 144),
(27, 129),
(152, 0),
(44, 180),
(118, 141),
(115, 129),
(210, 0),
(13, 164),
(27, 133),
(20, 192),
(139, 0),
(28, 166),
(17, 133),
(19, 193),
(224, 0),
(20, 161),
(145, 0),
(14, 193),
(12, 132),
(18, 161),
(17, 140),
(29, 192),
(246, 0),
(115, 178),
(28, 132),
(155, 0),
(12, 132),
(31, 165),
(20, 136),
(27, 193),
(142, 0),
(96, 164),
(18, 133),
(145, 0),
(23, 132),
(13, 165),
(13, 148),
(23, 193),
(19, 132),
(27, 178),
(83, 137),
(146, 0),
(145, 0),
(18, 166),
(96, 148),
(13, 193),
(159, 0),
(96, 166),
(20, 129),
(20, 193),
(27, 132),
(9, 160),
(96, 148),
(13, 192),
(159, 0),
(96, 180),
(142, 0),
(31, 193),
(155, 0),
(7, 166),
(224, 0),
(20, 192),
(27, 132),
(28, 160),
(17, 149),
(19, 193),
(96, 132),
(76, 164),
(208, 0),
(80, 192),
(78, 132),
(96, 160),
(27, 144),
(24, 193),
(140, 0),
(96, 178),
(17, 141),
(12, 193),
(224, 0),
(14, 161),
(17, 141),
(151, 0),
(14, 132),
(16, 165),
(96, 137),
(13, 193),
(155, 0),
(20, 161),
(29, 141),
(23, 192),
(24, 132),
(27, 178),
(10, 133),
(96, 192),
(140, 0),
(14, 180),
(17, 133),
(16, 192),
(144, 0),
(11, 163),
(13, 141),
(96, 192),
(17, 132),
(12, 178),
(96, 141),
(28, 192),
(27, 132),
(27, 130),
(18, 141),
(96, 193),
(31, 132),
(96, 181),
(13, 140),
(23, 193),
(224, 0),
(27, 166),
(142, 0),
(27, 192),
(24, 132),
(12, 183),
(96, 133),
(84, 192),
(14, 132),
(27, 178),
(10, 140),
(155, 0),
(9, 132),
(17, 160),
(56, 133),
(96, 192),
(82, 132),
(13, 160),
(27, 137),
(20, 193),
(139, 0),
(28, 161),
(145, 0),
(19, 192),
(118, 132),
(115, 165),
(20, 132),
(145, 0),
(14, 132),
(12, 167),
(146, 0),
(17, 193),
(29, 132),
(96, 176),
(28, 144),
(27, 193),
(140, 0),
(31, 180),
(148, 0),
(27, 192),
(14, 132),
(83, 160),
(18, 137),
(17, 193),
(23, 132),
(13, 165),
(13, 145),
(151, 0),
(147, 0),
(27, 178),
(96, 137),
(19, 193),
(159, 0),
(14, 160),
(25, 148),
(17, 193),
(142, 0),
(16, 180),
(27, 136),
(14, 193),
(224, 0),
(17, 178),
(12, 144),
(224, 0),
(28, 132),
(27, 160),
(13, 141),
(11, 193),
(96, 132),
(27, 165),
(30, 140),
(224, 0),
(146, 0),
(31, 165),
(29, 129),
(96, 192),
(140, 0),
(31, 161),
(24, 145),
(140, 0),
(96, 132),
(27, 165),
(29, 140),
(31, 192),
(154, 0),
(14, 161),
(27, 145),
(140, 0),
(18, 132),
(23, 167),
(96, 140),
(21, 129),
(14, 132),
(17, 165),
(9, 137),
(12, 193),
(155, 0),
(18, 161),
(96, 141),
(27, 192),
(148, 0),
(29, 178),
(23, 133),
(24, 192),
(155, 0),
(10, 180),
(96, 133),
(28, 192),
(14, 132),
(31, 130),
(28, 129),
(18, 193),
(31, 132),
(12, 180),
(13, 144),
(96, 193),
(31, 132),
(96, 160),
(13, 141),
(27, 193),
(18, 132),
(23, 181),
(26, 140),
(27, 193),
(156, 0),
(96, 166),
(79, 141),
(211, 0),
(76, 132),
(77, 160),
(75, 133),
(206, 0),
(182, 0),
(96, 129),
(59, 133),
(191, 0),
(173, 0),
];

assert!(block_data.len() <= BLOCK_SIZE);

let mut decoded_block: Vec<u8> = vec![];

for (i, byte) in block_data.iter().enumerate() {
let encoding = encoding_table[i];

decoded_block.push(((((*byte as usize) + encoding.0) ^ encoding.1) % 256) as u8);
}

decoded_block
}
11 changes: 11 additions & 0 deletions src/magic.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -888,6 +888,17 @@ pub fn patterns() -> Vec<signatures::common::Signature> {
description: signatures::binhdr::DESCRIPTION.to_string(),
extractor: None,
},
// Autel obfuscated firmware
signatures::common::Signature {
name: "autel".to_string(),
short: false,
magic_offset: 0,
always_display: false,
magic: signatures::autel::autel_magic(),
parser: signatures::autel::autel_parser,
description: signatures::autel::DESCRIPTION.to_string(),
extractor: Some(extractors::autel::autel_extractor()),
},
];

binary_signatures
Expand Down
1 change: 1 addition & 0 deletions src/signatures.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -108,6 +108,7 @@
pub mod aes;
pub mod androidsparse;
pub mod arcadyan;
pub mod autel;
pub mod binhdr;
pub mod bzip2;
pub mod cab;
Expand Down
Loading