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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
use std::{
convert::TryInto,
ffi::OsString,
mem::{size_of, MaybeUninit},
os::windows::ffi::OsStringExt,
ptr::null_mut,
};
use windows_sys::Win32::{
Foundation::{FALSE, HMODULE, MAX_PATH},
System::{
Diagnostics::Debug::ReadProcessMemory,
ProcessStatus::{
K32EnumProcessModules, K32GetModuleBaseNameW, K32GetModuleInformation, MODULEINFO,
},
},
};
use crate::{
error::{ProcessReaderError, ReadError},
ProcessHandle, ProcessReader,
};
impl ProcessReader {
pub fn new(process: ProcessHandle) -> Result<ProcessReader, ProcessReaderError> {
Ok(ProcessReader { process })
}
pub fn find_module(&self, module_name: &str) -> Result<usize, ProcessReaderError> {
let modules = self.get_module_list()?;
let module = modules.iter().find_map(|&module| {
let name = self.get_module_name(module);
// Crude way of mimicking Windows lower-case comparisons but
// sufficient for our use-cases.
if name.is_some_and(|name| name.eq_ignore_ascii_case(module_name)) {
self.get_module_info(module)
.map(|module| module.lpBaseOfDll as usize)
} else {
None
}
});
module.ok_or(ProcessReaderError::ModuleNotFound)
}
pub fn find_section(
&self,
module_address: usize,
section_name: &[u8; 8],
) -> Result<usize, ProcessReaderError> {
// We read only the first page from the module, this should be more than
// enough to read the header and section list. In the future we might do
// this incrementally but for now goblin requires an array to parse
// so we can't do it just yet.
const PAGE_SIZE: usize = 4096;
let bytes = self.copy_array(module_address as _, PAGE_SIZE)?;
let header = goblin::pe::header::Header::parse(&bytes)?;
// Skip the PE header so we can parse the sections
let optional_header_offset = header.dos_header.pe_pointer as usize
+ goblin::pe::header::SIZEOF_PE_MAGIC
+ goblin::pe::header::SIZEOF_COFF_HEADER;
let offset =
&mut (optional_header_offset + header.coff_header.size_of_optional_header as usize);
let sections = header.coff_header.sections(&bytes, offset)?;
for section in sections {
if section.name.eq(section_name) {
let address = module_address.checked_add(section.virtual_address as usize);
return address.ok_or(ProcessReaderError::InvalidAddress);
}
}
Err(ProcessReaderError::SectionNotFound)
}
fn get_module_list(&self) -> Result<Vec<HMODULE>, ProcessReaderError> {
let mut module_num: usize = 100;
let mut required_buffer_size: u32 = 0;
let mut module_array = Vec::<HMODULE>::with_capacity(module_num);
loop {
let buffer_size: u32 = (module_num * size_of::<HMODULE>()).try_into()?;
let res = unsafe {
K32EnumProcessModules(
self.process,
module_array.as_mut_ptr() as *mut _,
buffer_size,
&mut required_buffer_size as *mut _,
)
};
module_num = required_buffer_size as usize / size_of::<HMODULE>();
if res == 0 {
if required_buffer_size > buffer_size {
module_array = Vec::<HMODULE>::with_capacity(module_num);
} else {
return Err(ProcessReaderError::EnumProcessModulesError);
}
} else {
break;
}
}
// SAFETY: module_array has been filled by K32EnumProcessModules()
unsafe {
module_array.set_len(module_num);
};
Ok(module_array)
}
fn get_module_name(&self, module: HMODULE) -> Option<String> {
let mut path: [u16; MAX_PATH as usize] = [0; MAX_PATH as usize];
let res = unsafe {
K32GetModuleBaseNameW(self.process, module, (&mut path).as_mut_ptr(), MAX_PATH)
};
if res == 0 {
None
} else {
let name = OsString::from_wide(&path[0..res as usize]);
let name = name.to_str()?;
Some(name.to_string())
}
}
fn get_module_info(&self, module: HMODULE) -> Option<MODULEINFO> {
let mut info: MaybeUninit<MODULEINFO> = MaybeUninit::uninit();
let res = unsafe {
K32GetModuleInformation(
self.process,
module,
info.as_mut_ptr(),
size_of::<MODULEINFO>() as u32,
)
};
if res == 0 {
None
} else {
let info = unsafe { info.assume_init() };
Some(info)
}
}
pub fn copy_object_shallow<T>(&self, src: usize) -> Result<MaybeUninit<T>, ReadError> {
let mut object = MaybeUninit::<T>::uninit();
let res = unsafe {
ReadProcessMemory(
self.process,
src as _,
object.as_mut_ptr() as _,
size_of::<T>(),
null_mut(),
)
};
if res != FALSE {
Ok(object)
} else {
Err(ReadError::ReadProcessMemoryError)
}
}
pub fn copy_object<T>(&self, src: usize) -> Result<T, ReadError> {
let object = self.copy_object_shallow(src)?;
Ok(unsafe { object.assume_init() })
}
pub fn copy_array<T>(&self, src: usize, num: usize) -> Result<Vec<T>, ReadError> {
let num_of_bytes = num * size_of::<T>();
let mut array: Vec<T> = Vec::with_capacity(num);
let res = unsafe {
ReadProcessMemory(
self.process,
src as _,
array.as_mut_ptr() as _,
num_of_bytes,
null_mut(),
)
};
if res != FALSE {
unsafe {
array.set_len(num);
}
Ok(array)
} else {
Err(ReadError::ReadProcessMemoryError)
}
}
}