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denoland-deno/cli/standalone/binary.rs
Bartek Iwańczuk 2bb013f9ba
refactor: version module exports a single const struct (#25014)
This commit rewrites the internal `version` module that exported
various information about the current executable. Instead of exporting
several consts, we are now exporting a single const structure that 
contains all the necessary information.

This is the first step towards cleaning up how we use this information
and should allow us to use SUI to be able to patch this information
in already produced binary making it easier to cut new releases.

---------

Co-authored-by: Divy Srivastava <dj.srivastava23@gmail.com>
2024-08-15 23:47:16 +02:00

806 lines
26 KiB
Rust

// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
use std::borrow::Cow;
use std::collections::BTreeMap;
use std::collections::HashMap;
use std::collections::VecDeque;
use std::env::current_exe;
use std::ffi::OsString;
use std::fs;
use std::fs::File;
use std::future::Future;
use std::io::Read;
use std::io::Seek;
use std::io::SeekFrom;
use std::io::Write;
use std::path::Path;
use std::path::PathBuf;
use std::process::Command;
use deno_ast::ModuleSpecifier;
use deno_config::workspace::PackageJsonDepResolution;
use deno_config::workspace::ResolverWorkspaceJsrPackage;
use deno_config::workspace::Workspace;
use deno_config::workspace::WorkspaceResolver;
use deno_core::anyhow::bail;
use deno_core::anyhow::Context;
use deno_core::error::AnyError;
use deno_core::futures::io::AllowStdIo;
use deno_core::futures::AsyncReadExt;
use deno_core::futures::AsyncSeekExt;
use deno_core::serde_json;
use deno_core::url::Url;
use deno_npm::NpmSystemInfo;
use deno_runtime::deno_node::PackageJson;
use deno_semver::npm::NpmVersionReqParseError;
use deno_semver::package::PackageReq;
use deno_semver::Version;
use deno_semver::VersionReqSpecifierParseError;
use eszip::EszipRelativeFileBaseUrl;
use indexmap::IndexMap;
use log::Level;
use serde::Deserialize;
use serde::Serialize;
use crate::args::CaData;
use crate::args::CliOptions;
use crate::args::CompileFlags;
use crate::args::PackageJsonInstallDepsProvider;
use crate::args::PermissionFlags;
use crate::args::UnstableConfig;
use crate::cache::DenoDir;
use crate::file_fetcher::FileFetcher;
use crate::http_util::HttpClientProvider;
use crate::npm::CliNpmResolver;
use crate::npm::InnerCliNpmResolverRef;
use crate::shared::ReleaseChannel;
use crate::standalone::virtual_fs::VfsEntry;
use crate::util::archive;
use crate::util::fs::canonicalize_path_maybe_not_exists;
use crate::util::progress_bar::ProgressBar;
use crate::util::progress_bar::ProgressBarStyle;
use super::virtual_fs::FileBackedVfs;
use super::virtual_fs::VfsBuilder;
use super::virtual_fs::VfsRoot;
use super::virtual_fs::VirtualDirectory;
const MAGIC_TRAILER: &[u8; 8] = b"d3n0l4nd";
#[derive(Deserialize, Serialize)]
pub enum NodeModules {
Managed {
/// Relative path for the node_modules directory in the vfs.
node_modules_dir: Option<String>,
},
Byonm {
root_node_modules_dir: Option<String>,
},
}
#[derive(Deserialize, Serialize)]
pub struct SerializedWorkspaceResolverImportMap {
pub specifier: String,
pub json: String,
}
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub struct SerializedResolverWorkspaceJsrPackage {
pub relative_base: String,
pub name: String,
pub version: Option<Version>,
pub exports: IndexMap<String, String>,
}
#[derive(Deserialize, Serialize)]
pub struct SerializedWorkspaceResolver {
pub import_map: Option<SerializedWorkspaceResolverImportMap>,
pub jsr_pkgs: Vec<SerializedResolverWorkspaceJsrPackage>,
pub package_jsons: BTreeMap<String, serde_json::Value>,
pub pkg_json_resolution: PackageJsonDepResolution,
}
#[derive(Deserialize, Serialize)]
pub struct Metadata {
pub argv: Vec<String>,
pub seed: Option<u64>,
pub permissions: PermissionFlags,
pub location: Option<Url>,
pub v8_flags: Vec<String>,
pub log_level: Option<Level>,
pub ca_stores: Option<Vec<String>>,
pub ca_data: Option<Vec<u8>>,
pub unsafely_ignore_certificate_errors: Option<Vec<String>>,
pub env_vars_from_env_file: HashMap<String, String>,
pub workspace_resolver: SerializedWorkspaceResolver,
pub entrypoint_key: String,
pub node_modules: Option<NodeModules>,
pub disable_deprecated_api_warning: bool,
pub unstable_config: UnstableConfig,
}
pub fn load_npm_vfs(root_dir_path: PathBuf) -> Result<FileBackedVfs, AnyError> {
let data = libsui::find_section("d3n0l4nd").unwrap();
// We do the first part sync so it can complete quickly
let trailer: [u8; TRAILER_SIZE] = data[0..TRAILER_SIZE].try_into().unwrap();
let trailer = match Trailer::parse(&trailer)? {
None => panic!("Could not find trailer"),
Some(trailer) => trailer,
};
let data = &data[TRAILER_SIZE..];
let vfs_data =
&data[trailer.npm_vfs_pos as usize..trailer.npm_files_pos as usize];
let mut dir: VirtualDirectory = serde_json::from_slice(vfs_data)?;
// align the name of the directory with the root dir
dir.name = root_dir_path
.file_name()
.unwrap()
.to_string_lossy()
.to_string();
let fs_root = VfsRoot {
dir,
root_path: root_dir_path,
start_file_offset: trailer.npm_files_pos,
};
Ok(FileBackedVfs::new(data.to_vec(), fs_root))
}
fn write_binary_bytes(
mut file_writer: File,
original_bin: Vec<u8>,
metadata: &Metadata,
eszip: eszip::EszipV2,
npm_vfs: Option<&VirtualDirectory>,
npm_files: &Vec<Vec<u8>>,
compile_flags: &CompileFlags,
) -> Result<(), AnyError> {
let metadata = serde_json::to_string(metadata)?.as_bytes().to_vec();
let npm_vfs = serde_json::to_string(&npm_vfs)?.as_bytes().to_vec();
let eszip_archive = eszip.into_bytes();
let mut writer = Vec::new();
// write the trailer, which includes the positions
// of the data blocks in the file
writer.write_all(&{
let metadata_pos = eszip_archive.len() as u64;
let npm_vfs_pos = metadata_pos + (metadata.len() as u64);
let npm_files_pos = npm_vfs_pos + (npm_vfs.len() as u64);
Trailer {
eszip_pos: 0,
metadata_pos,
npm_vfs_pos,
npm_files_pos,
}
.as_bytes()
})?;
writer.write_all(&eszip_archive)?;
writer.write_all(&metadata)?;
writer.write_all(&npm_vfs)?;
for file in npm_files {
writer.write_all(file)?;
}
let target = compile_flags.resolve_target();
if target.contains("linux") {
libsui::Elf::new(&original_bin).append(
"d3n0l4nd",
&writer,
&mut file_writer,
)?;
} else if target.contains("windows") {
let mut pe = libsui::PortableExecutable::from(&original_bin)?;
if let Some(icon) = compile_flags.icon.as_ref() {
let icon = std::fs::read(icon)?;
pe = pe.set_icon(&icon)?;
}
pe.write_resource("d3n0l4nd", writer)?
.build(&mut file_writer)?;
} else if target.contains("darwin") {
libsui::Macho::from(original_bin)?
.write_section("d3n0l4nd", writer)?
.build_and_sign(&mut file_writer)?;
}
Ok(())
}
pub fn is_standalone_binary(exe_path: &Path) -> bool {
let Ok(data) = std::fs::read(exe_path) else {
return false;
};
libsui::utils::is_elf(&data)
|| libsui::utils::is_pe(&data)
|| libsui::utils::is_macho(&data)
}
/// This function will try to run this binary as a standalone binary
/// produced by `deno compile`. It determines if this is a standalone
/// binary by skipping over the trailer width at the end of the file,
/// then checking for the magic trailer string `d3n0l4nd`. If found,
/// the bundle is executed. If not, this function exits with `Ok(None)`.
pub fn extract_standalone(
cli_args: Cow<Vec<OsString>>,
) -> Result<
Option<impl Future<Output = Result<(Metadata, eszip::EszipV2), AnyError>>>,
AnyError,
> {
let Some(data) = libsui::find_section("d3n0l4nd") else {
return Ok(None);
};
// We do the first part sync so it can complete quickly
let trailer = match Trailer::parse(&data[0..TRAILER_SIZE])? {
None => return Ok(None),
Some(trailer) => trailer,
};
let cli_args = cli_args.into_owned();
// If we have an eszip, read it out
Ok(Some(async move {
let bufreader =
deno_core::futures::io::BufReader::new(&data[TRAILER_SIZE..]);
let (eszip, loader) = eszip::EszipV2::parse(bufreader)
.await
.context("Failed to parse eszip header")?;
let bufreader = loader.await.context("Failed to parse eszip archive")?;
let mut metadata = String::new();
bufreader
.take(trailer.metadata_len())
.read_to_string(&mut metadata)
.await
.context("Failed to read metadata from the current executable")?;
let mut metadata: Metadata = serde_json::from_str(&metadata).unwrap();
metadata.argv.reserve(cli_args.len() - 1);
for arg in cli_args.into_iter().skip(1) {
metadata.argv.push(arg.into_string().unwrap());
}
Ok((metadata, eszip))
}))
}
const TRAILER_SIZE: usize = std::mem::size_of::<Trailer>() + 8; // 8 bytes for the magic trailer string
struct Trailer {
eszip_pos: u64,
metadata_pos: u64,
npm_vfs_pos: u64,
npm_files_pos: u64,
}
impl Trailer {
pub fn parse(trailer: &[u8]) -> Result<Option<Trailer>, AnyError> {
let (magic_trailer, rest) = trailer.split_at(8);
if magic_trailer != MAGIC_TRAILER {
return Ok(None);
}
let (eszip_archive_pos, rest) = rest.split_at(8);
let (metadata_pos, rest) = rest.split_at(8);
let (npm_vfs_pos, npm_files_pos) = rest.split_at(8);
let eszip_archive_pos = u64_from_bytes(eszip_archive_pos)?;
let metadata_pos = u64_from_bytes(metadata_pos)?;
let npm_vfs_pos = u64_from_bytes(npm_vfs_pos)?;
let npm_files_pos = u64_from_bytes(npm_files_pos)?;
Ok(Some(Trailer {
eszip_pos: eszip_archive_pos,
metadata_pos,
npm_vfs_pos,
npm_files_pos,
}))
}
pub fn metadata_len(&self) -> u64 {
self.npm_vfs_pos - self.metadata_pos
}
pub fn npm_vfs_len(&self) -> u64 {
self.npm_files_pos - self.npm_vfs_pos
}
pub fn as_bytes(&self) -> Vec<u8> {
let mut trailer = MAGIC_TRAILER.to_vec();
trailer.write_all(&self.eszip_pos.to_be_bytes()).unwrap();
trailer.write_all(&self.metadata_pos.to_be_bytes()).unwrap();
trailer.write_all(&self.npm_vfs_pos.to_be_bytes()).unwrap();
trailer
.write_all(&self.npm_files_pos.to_be_bytes())
.unwrap();
trailer
}
}
fn u64_from_bytes(arr: &[u8]) -> Result<u64, AnyError> {
let fixed_arr: &[u8; 8] = arr
.try_into()
.context("Failed to convert the buffer into a fixed-size array")?;
Ok(u64::from_be_bytes(*fixed_arr))
}
pub struct DenoCompileBinaryWriter<'a> {
deno_dir: &'a DenoDir,
file_fetcher: &'a FileFetcher,
http_client_provider: &'a HttpClientProvider,
npm_resolver: &'a dyn CliNpmResolver,
workspace_resolver: &'a WorkspaceResolver,
npm_system_info: NpmSystemInfo,
}
impl<'a> DenoCompileBinaryWriter<'a> {
#[allow(clippy::too_many_arguments)]
pub fn new(
deno_dir: &'a DenoDir,
file_fetcher: &'a FileFetcher,
http_client_provider: &'a HttpClientProvider,
npm_resolver: &'a dyn CliNpmResolver,
workspace_resolver: &'a WorkspaceResolver,
npm_system_info: NpmSystemInfo,
) -> Self {
Self {
deno_dir,
file_fetcher,
http_client_provider,
npm_resolver,
workspace_resolver,
npm_system_info,
}
}
pub async fn write_bin(
&self,
writer: File,
eszip: eszip::EszipV2,
root_dir_url: EszipRelativeFileBaseUrl<'_>,
entrypoint: &ModuleSpecifier,
compile_flags: &CompileFlags,
cli_options: &CliOptions,
) -> Result<(), AnyError> {
// Select base binary based on target
let mut original_binary = self.get_base_binary(compile_flags).await?;
if compile_flags.no_terminal {
let target = compile_flags.resolve_target();
if !target.contains("windows") {
bail!(
"The `--no-terminal` flag is only available when targeting Windows (current: {})",
target,
)
}
set_windows_binary_to_gui(&mut original_binary)?;
}
if compile_flags.icon.is_some() {
let target = compile_flags.resolve_target();
if !target.contains("windows") {
bail!(
"The `--icon` flag is only available when targeting Windows (current: {})",
target,
)
}
}
self.write_standalone_binary(
writer,
original_binary,
eszip,
root_dir_url,
entrypoint,
cli_options,
compile_flags,
)
}
async fn get_base_binary(
&self,
compile_flags: &CompileFlags,
) -> Result<Vec<u8>, AnyError> {
// Used for testing.
//
// Phase 2 of the 'min sized' deno compile RFC talks
// about adding this as a flag.
if let Some(path) = std::env::var_os("DENORT_BIN") {
return std::fs::read(&path).with_context(|| {
format!("Could not find denort at '{}'", path.to_string_lossy())
});
}
let target = compile_flags.resolve_target();
let binary_name = format!("denort-{target}.zip");
let binary_path_suffix =
match crate::version::DENO_VERSION_INFO.release_channel {
ReleaseChannel::Canary => {
format!(
"canary/{}/{}",
crate::version::DENO_VERSION_INFO.git_hash,
binary_name
)
}
ReleaseChannel::Stable => {
format!("release/v{}/{}", env!("CARGO_PKG_VERSION"), binary_name)
}
_ => bail!(
"`deno compile` current doesn't support {} release channel",
crate::version::DENO_VERSION_INFO.release_channel.name()
),
};
let download_directory = self.deno_dir.dl_folder_path();
let binary_path = download_directory.join(&binary_path_suffix);
if !binary_path.exists() {
self
.download_base_binary(&download_directory, &binary_path_suffix)
.await?;
}
let archive_data = std::fs::read(binary_path)?;
let temp_dir = tempfile::TempDir::new()?;
let base_binary_path = archive::unpack_into_dir(archive::UnpackArgs {
exe_name: "denort",
archive_name: &binary_name,
archive_data: &archive_data,
is_windows: target.contains("windows"),
dest_path: temp_dir.path(),
})?;
let base_binary = std::fs::read(base_binary_path)?;
drop(temp_dir); // delete the temp dir
Ok(base_binary)
}
async fn download_base_binary(
&self,
output_directory: &Path,
binary_path_suffix: &str,
) -> Result<(), AnyError> {
let download_url = format!("https://dl.deno.land/{binary_path_suffix}");
let maybe_bytes = {
let progress_bars = ProgressBar::new(ProgressBarStyle::DownloadBars);
let progress = progress_bars.update(&download_url);
self
.http_client_provider
.get_or_create()?
.download_with_progress(download_url.parse()?, None, &progress)
.await?
};
let bytes = match maybe_bytes {
Some(bytes) => bytes,
None => {
log::info!("Download could not be found, aborting");
std::process::exit(1)
}
};
std::fs::create_dir_all(output_directory)?;
let output_path = output_directory.join(binary_path_suffix);
std::fs::create_dir_all(output_path.parent().unwrap())?;
tokio::fs::write(output_path, bytes).await?;
Ok(())
}
/// This functions creates a standalone deno binary by appending a bundle
/// and magic trailer to the currently executing binary.
#[allow(clippy::too_many_arguments)]
fn write_standalone_binary(
&self,
writer: File,
original_bin: Vec<u8>,
mut eszip: eszip::EszipV2,
root_dir_url: EszipRelativeFileBaseUrl<'_>,
entrypoint: &ModuleSpecifier,
cli_options: &CliOptions,
compile_flags: &CompileFlags,
) -> Result<(), AnyError> {
let ca_data = match cli_options.ca_data() {
Some(CaData::File(ca_file)) => Some(
std::fs::read(ca_file)
.with_context(|| format!("Reading: {ca_file}"))?,
),
Some(CaData::Bytes(bytes)) => Some(bytes.clone()),
None => None,
};
let root_path = root_dir_url.inner().to_file_path().unwrap();
let (npm_vfs, npm_files, node_modules) = match self.npm_resolver.as_inner()
{
InnerCliNpmResolverRef::Managed(managed) => {
let snapshot =
managed.serialized_valid_snapshot_for_system(&self.npm_system_info);
if !snapshot.as_serialized().packages.is_empty() {
let (root_dir, files) = self
.build_vfs(&root_path, cli_options)?
.into_dir_and_files();
eszip.add_npm_snapshot(snapshot);
(
Some(root_dir),
files,
Some(NodeModules::Managed {
node_modules_dir: self.npm_resolver.root_node_modules_path().map(
|path| {
root_dir_url
.specifier_key(
&ModuleSpecifier::from_directory_path(path).unwrap(),
)
.into_owned()
},
),
}),
)
} else {
(None, Vec::new(), None)
}
}
InnerCliNpmResolverRef::Byonm(resolver) => {
let (root_dir, files) = self
.build_vfs(&root_path, cli_options)?
.into_dir_and_files();
(
Some(root_dir),
files,
Some(NodeModules::Byonm {
root_node_modules_dir: resolver.root_node_modules_path().map(
|node_modules_dir| {
root_dir_url
.specifier_key(
&ModuleSpecifier::from_directory_path(node_modules_dir)
.unwrap(),
)
.into_owned()
},
),
}),
)
}
};
let env_vars_from_env_file = match cli_options.env_file_name() {
Some(env_filename) => {
log::info!("{} Environment variables from the file \"{}\" were embedded in the generated executable file", crate::colors::yellow("Warning"), env_filename);
get_file_env_vars(env_filename.to_string())?
}
None => Default::default(),
};
let metadata = Metadata {
argv: compile_flags.args.clone(),
seed: cli_options.seed(),
location: cli_options.location_flag().clone(),
permissions: cli_options.permission_flags().clone(),
v8_flags: cli_options.v8_flags().clone(),
unsafely_ignore_certificate_errors: cli_options
.unsafely_ignore_certificate_errors()
.clone(),
log_level: cli_options.log_level(),
ca_stores: cli_options.ca_stores().clone(),
ca_data,
env_vars_from_env_file,
entrypoint_key: root_dir_url.specifier_key(entrypoint).into_owned(),
workspace_resolver: SerializedWorkspaceResolver {
import_map: self.workspace_resolver.maybe_import_map().map(|i| {
SerializedWorkspaceResolverImportMap {
specifier: if i.base_url().scheme() == "file" {
root_dir_url.specifier_key(i.base_url()).into_owned()
} else {
// just make a remote url local
"deno.json".to_string()
},
json: i.to_json(),
}
}),
jsr_pkgs: self
.workspace_resolver
.jsr_packages()
.map(|pkg| SerializedResolverWorkspaceJsrPackage {
relative_base: root_dir_url.specifier_key(&pkg.base).into_owned(),
name: pkg.name.clone(),
version: pkg.version.clone(),
exports: pkg.exports.clone(),
})
.collect(),
package_jsons: self
.workspace_resolver
.package_jsons()
.map(|pkg_json| {
(
root_dir_url
.specifier_key(&pkg_json.specifier())
.into_owned(),
serde_json::to_value(pkg_json).unwrap(),
)
})
.collect(),
pkg_json_resolution: self.workspace_resolver.pkg_json_dep_resolution(),
},
node_modules,
disable_deprecated_api_warning: cli_options
.disable_deprecated_api_warning,
unstable_config: UnstableConfig {
legacy_flag_enabled: cli_options.legacy_unstable_flag(),
bare_node_builtins: cli_options.unstable_bare_node_builtins(),
byonm: cli_options.use_byonm(),
sloppy_imports: cli_options.unstable_sloppy_imports(),
features: cli_options.unstable_features(),
},
};
write_binary_bytes(
writer,
original_bin,
&metadata,
eszip,
npm_vfs.as_ref(),
&npm_files,
compile_flags,
)
}
fn build_vfs(
&self,
root_path: &Path,
cli_options: &CliOptions,
) -> Result<VfsBuilder, AnyError> {
fn maybe_warn_different_system(system_info: &NpmSystemInfo) {
if system_info != &NpmSystemInfo::default() {
log::warn!("{} The node_modules directory may be incompatible with the target system.", crate::colors::yellow("Warning"));
}
}
match self.npm_resolver.as_inner() {
InnerCliNpmResolverRef::Managed(npm_resolver) => {
if let Some(node_modules_path) = npm_resolver.root_node_modules_path() {
maybe_warn_different_system(&self.npm_system_info);
let mut builder = VfsBuilder::new(root_path.to_path_buf())?;
builder.add_dir_recursive(node_modules_path)?;
Ok(builder)
} else {
// DO NOT include the user's registry url as it may contain credentials,
// but also don't make this dependent on the registry url
let root_path = npm_resolver.global_cache_root_folder();
let mut builder = VfsBuilder::new(root_path)?;
for package in npm_resolver.all_system_packages(&self.npm_system_info)
{
let folder =
npm_resolver.resolve_pkg_folder_from_pkg_id(&package.id)?;
builder.add_dir_recursive(&folder)?;
}
// Flatten all the registries folders into a single "node_modules/localhost" folder
// that will be used by denort when loading the npm cache. This avoids us exposing
// the user's private registry information and means we don't have to bother
// serializing all the different registry config into the binary.
builder.with_root_dir(|root_dir| {
root_dir.name = "node_modules".to_string();
let mut new_entries = Vec::with_capacity(root_dir.entries.len());
let mut localhost_entries = IndexMap::new();
for entry in std::mem::take(&mut root_dir.entries) {
match entry {
VfsEntry::Dir(dir) => {
for entry in dir.entries {
log::debug!(
"Flattening {} into node_modules",
entry.name()
);
if let Some(existing) =
localhost_entries.insert(entry.name().to_string(), entry)
{
panic!(
"Unhandled scenario where a duplicate entry was found: {:?}",
existing
);
}
}
}
VfsEntry::File(_) | VfsEntry::Symlink(_) => {
new_entries.push(entry);
}
}
}
new_entries.push(VfsEntry::Dir(VirtualDirectory {
name: "localhost".to_string(),
entries: localhost_entries.into_iter().map(|(_, v)| v).collect(),
}));
// needs to be sorted by name
new_entries.sort_by(|a, b| a.name().cmp(b.name()));
root_dir.entries = new_entries;
});
Ok(builder)
}
}
InnerCliNpmResolverRef::Byonm(_) => {
maybe_warn_different_system(&self.npm_system_info);
let mut builder = VfsBuilder::new(root_path.to_path_buf())?;
for pkg_json in cli_options.workspace().package_jsons() {
builder.add_file_at_path(&pkg_json.path)?;
}
// traverse and add all the node_modules directories in the workspace
let mut pending_dirs = VecDeque::new();
pending_dirs.push_back(
cli_options.workspace().root_dir().to_file_path().unwrap(),
);
while let Some(pending_dir) = pending_dirs.pop_front() {
let entries = fs::read_dir(&pending_dir).with_context(|| {
format!("Failed reading: {}", pending_dir.display())
})?;
for entry in entries {
let entry = entry?;
let path = entry.path();
if !path.is_dir() {
continue;
}
if path.ends_with("node_modules") {
builder.add_dir_recursive(&path)?;
} else {
pending_dirs.push_back(path);
}
}
}
Ok(builder)
}
}
}
}
/// This function returns the environment variables specified
/// in the passed environment file.
fn get_file_env_vars(
filename: String,
) -> Result<HashMap<String, String>, dotenvy::Error> {
let mut file_env_vars = HashMap::new();
for item in dotenvy::from_filename_iter(filename)? {
let Ok((key, val)) = item else {
continue; // this failure will be warned about on load
};
file_env_vars.insert(key, val);
}
Ok(file_env_vars)
}
/// This function sets the subsystem field in the PE header to 2 (GUI subsystem)
/// For more information about the PE header: https://learn.microsoft.com/en-us/windows/win32/debug/pe-format
fn set_windows_binary_to_gui(bin: &mut [u8]) -> Result<(), AnyError> {
// Get the PE header offset located in an i32 found at offset 60
// See: https://learn.microsoft.com/en-us/windows/win32/debug/pe-format#ms-dos-stub-image-only
let start_pe = u32::from_le_bytes((bin[60..64]).try_into()?);
// Get image type (PE32 or PE32+) indicates whether the binary is 32 or 64 bit
// The used offset and size values can be found here:
// https://learn.microsoft.com/en-us/windows/win32/debug/pe-format#optional-header-image-only
let start_32 = start_pe as usize + 28;
let magic_32 =
u16::from_le_bytes(bin[(start_32)..(start_32 + 2)].try_into()?);
let start_64 = start_pe as usize + 24;
let magic_64 =
u16::from_le_bytes(bin[(start_64)..(start_64 + 2)].try_into()?);
// Take the standard fields size for the current architecture (32 or 64 bit)
// This is the ofset for the Windows-Specific fields
let standard_fields_size = if magic_32 == 0x10b {
28
} else if magic_64 == 0x20b {
24
} else {
bail!("Could not find a matching magic field in the PE header")
};
// Set the subsystem field (offset 68) to 2 (GUI subsystem)
// For all possible options, see: https://learn.microsoft.com/en-us/windows/win32/debug/pe-format#optional-header-windows-specific-fields-image-only
let subsystem_offset = 68;
let subsystem_start =
start_pe as usize + standard_fields_size + subsystem_offset;
let subsystem: u16 = 2;
bin[(subsystem_start)..(subsystem_start + 2)]
.copy_from_slice(&subsystem.to_le_bytes());
Ok(())
}