Files
XSnap/native/rust/src/sig.rs
2026-01-13 23:41:29 +05:30

148 lines
4.6 KiB
Rust

use std::{fs::File, os::unix::io::AsRawFd, sync::Mutex};
use nix::libc;
use procfs::process::MMPermissions;
use crate::mapped_lib::MappedLib;
static SIGNATURE_CACHE: Mutex<Vec<(String, Vec<usize>)>> = Mutex::new(Vec::new());
pub fn add_signatures(signatures: Vec<(String, Vec<usize>)>) {
SIGNATURE_CACHE.lock().unwrap().extend(signatures);
}
pub fn get_signatures() -> Vec<(String, Vec<usize>)> {
SIGNATURE_CACHE.lock().unwrap().clone()
}
fn read_region_bytes(start: usize, size: usize) -> Option<Vec<u8>> {
let file = File::open("/proc/self/mem").ok();
if let Some(file) = file {
let fd = file.as_raw_fd();
let mut buffer = vec![0u8; size];
let mut offset = 0usize;
while offset < size {
let read = unsafe {
libc::pread(
fd,
buffer[offset..].as_mut_ptr() as *mut libc::c_void,
(size - offset) as libc::size_t,
(start + offset) as libc::off_t,
)
};
if read < 0 {
warn!(
"Failed to read /proc/self/mem at {:#x}: {}",
start,
std::io::Error::last_os_error()
);
return None;
}
if read == 0 {
break;
}
offset += read as usize;
}
if offset == size {
return Some(buffer);
}
warn!("Short read from /proc/self/mem at {:#x}: {} < {}", start, offset, size);
}
None
}
pub fn find_signatures(module_base: usize, bytes_buffer: &[u8], pattern: &str, once: bool) -> Vec<usize> {
let mut results = Vec::new();
let mut bytes = Vec::new();
let mut mask = Vec::new();
let mut i = 0;
if let Some(cache) = SIGNATURE_CACHE.lock().unwrap().iter().find(|(sig, _)| sig == pattern) {
return cache.1.clone().into_iter().map(|offset| module_base + offset).collect();
}
while i < pattern.len() {
if pattern.chars().nth(i).unwrap() == '?' {
bytes.push(0);
mask.push('?');
} else {
bytes.push(u8::from_str_radix(&pattern[i..i+2], 16).unwrap());
mask.push('x');
}
i += 3;
}
let mut i = 0;
let size = bytes_buffer.len().saturating_sub(bytes.len());
while i < size {
let mut found = true;
let mut j = 0;
while j < bytes.len() {
if mask[j] == '?' || bytes[j] == bytes_buffer[i + j] {
j += 1;
continue;
}
found = false;
break;
}
if found {
if once {
SIGNATURE_CACHE.lock().unwrap().push((pattern.to_string(), vec![i]));
return vec![module_base + i];
}
results.push(module_base + i);
}
i += 1;
}
SIGNATURE_CACHE.lock().unwrap().push((pattern.to_string(), results.clone()));
results
}
pub fn find_signature_executable(mapped_lib: &MappedLib, pattern: &str) -> Option<usize> {
let executable_regions = mapped_lib.regions.iter().filter(|region| {
region.perms.contains(MMPermissions::EXECUTE)
}).collect::<Vec<_>>();
for region in executable_regions {
let size = (region.end - region.start) as usize;
let module_base = region.start as usize;
if size > 0 {
let bytes_buffer = match read_region_bytes(module_base, size) {
Some(buffer) => buffer,
None => {
warn!("Unable to read executable region: {:#x} - {:#x}", region.start, region.end);
continue;
}
};
let results = find_signatures(module_base, &bytes_buffer, pattern, true);
if results.is_empty() {
warn!("Signature not found in region: {:#x} - {:#x}", region.start, region.end);
} else {
debug!("Found {} results in region: {:#x} - {:#x}", results.len(), region.start, region.end);
return Some(results[0]);
}
}
}
None
}
pub fn find_signature(mapped_lib: &MappedLib, _arm64_pattern: &str, _arm64_offset: i64, _arm32_pattern: &str, _arm32_offset: i64) -> Option<usize> {
#[cfg(target_arch = "aarch64")]
{
return find_signature_executable(mapped_lib, _arm64_pattern).map(|address| (address as i64 + _arm64_offset) as usize);
}
#[cfg(target_arch = "arm")]
{
return find_signature_executable(mapped_lib, _arm32_pattern).map(|address| (address as i64 + _arm32_offset) as usize);
}
}