use std::{
borrow::Cow,
env,
error::Error,
ffi::OsStr,
fs,
io::Cursor,
path::{Path, PathBuf},
};
use flate2::read::GzDecoder;
use reqwest::blocking::Response;
use sigstore_trust_root::{TrustedRoot, SIGSTORE_PRODUCTION_TRUSTED_ROOT};
use sigstore_types::Bundle;
use sigstore_verify::{verify, VerificationPolicy};
use tar::{Archive, EntryType};
const DEFAULT_PDFIUM_BUILD_ID: &str = "7802";
const PDFIUM_ATTESTATION_NAME: &str = "pdfium-attestation.json";
const PDFIUM_CERTIFICATE_ISSUER: &str = "https://token.actions.githubusercontent.com";
const VERIFIED_MARKER_FILE: &str = ".sigstore-verified";
#[allow(dead_code)]
fn try_link_pdfium() -> Result<(), Box<dyn Error>> {
let bin_ext = [
OsStr::new("dll"),
OsStr::new("lib"),
OsStr::new("so"),
OsStr::new("a"),
];
let build_id = env::var("WINPRINT_PDFIUM_BUILD_ID")
.unwrap_or_else(|_| DEFAULT_PDFIUM_BUILD_ID.to_string());
let mut target_path = PathBuf::from(env::var("OUT_DIR")?);
target_path.push(format!("pdfium_binaries_{}", build_id));
fs::create_dir_all(target_path.as_path())?;
let has_bin = fs::read_dir(target_path.as_path())?.any(|x| {
bin_ext.iter().any(|s| {
x.as_ref()
.ok()
.and_then(|d| {
if Path::new(d.file_name().as_os_str()).extension() == Some(s) {
Some(())
} else {
None
}
})
.is_some()
})
});
let verified_marker = target_path.join(VERIFIED_MARKER_FILE);
if !has_bin || !verified_marker.exists() {
let platform_name = match (
env::var("CARGO_CFG_TARGET_OS")?.as_str(),
env::var("CARGO_CFG_TARGET_ARCH")?.as_str(),
) {
("windows", "x86") => "win-x86",
("windows", "x86_64") => "win-x64",
("windows", "aarch64") => "win-arm64",
_ => return Err("Unsupported target arch".into()),
};
let binary_package_name = format!("pdfium-{}.tgz", platform_name);
let binary_package_url = release_asset_url(&build_id, &binary_package_name);
let binary_package = download_asset(binary_package_url.as_str())?;
let attestation_url = release_asset_url(&build_id, PDFIUM_ATTESTATION_NAME);
let attestation = download_asset(attestation_url.as_str())?;
verify_pdfium_attestation(binary_package.as_slice(), attestation.as_slice())?;
fs::remove_dir_all(target_path.as_path())?;
fs::create_dir_all(target_path.as_path())?;
unpack_pdfium_archive(binary_package.as_slice(), target_path.as_path(), &bin_ext)?;
fs::write(
verified_marker,
format!(
"Verified {} with {}\n",
binary_package_name, PDFIUM_ATTESTATION_NAME
),
)?;
}
println!(
"cargo:rustc-link-search=native={}",
target_path.to_str().unwrap()
);
println!("cargo:rustc-link-lib=dylib=pdfium");
Ok(())
}
fn release_asset_url(build_id: &str, file_name: &str) -> String {
format!(
"https://github.com/bblanchon/pdfium-binaries/releases/download/chromium/{}/{}",
build_id, file_name
)
}
fn download_asset(url: &str) -> Result<Vec<u8>, Box<dyn Error>> {
let resp = reqwest::blocking::get(url)?;
ensure_success(resp, url)
}
fn ensure_success(resp: Response, url: &str) -> Result<Vec<u8>, Box<dyn Error>> {
if !resp.status().is_success() {
return Err(format!("Failed to download asset from {}", url).into());
}
Ok(resp.bytes()?.to_vec())
}
fn verify_pdfium_attestation(
binary_package: &[u8],
attestation_json: &[u8],
) -> Result<(), Box<dyn Error>> {
let bundle = Bundle::from_json(std::str::from_utf8(attestation_json)?)?;
let trusted_root = TrustedRoot::from_json(SIGSTORE_PRODUCTION_TRUSTED_ROOT)?;
let policy = VerificationPolicy::default().require_issuer(PDFIUM_CERTIFICATE_ISSUER);
verify(binary_package, &bundle, &policy, &trusted_root)
.map_err(|err| format!("Failed to verify PDFium Sigstore attestation: {err}"))?;
Ok(())
}
fn unpack_pdfium_archive(
archive_bytes: &[u8],
target_path: &Path,
bin_ext: &[&OsStr],
) -> Result<(), Box<dyn Error>> {
let tar = GzDecoder::new(Cursor::new(archive_bytes));
let mut archive = Archive::new(tar);
for entry in archive.entries()? {
let mut file = entry?;
if file.header().entry_type() == EntryType::Regular {
let file_path = file.path()?;
let file_extension = file_path.extension();
let is_bin = bin_ext.iter().any(|s| file_extension == Some(s));
if is_bin {
if let Some(file_name_raw) = file_path.file_name() {
let mut file_name_str = file_name_raw.to_string_lossy();
if let Some(s) = file_name_str.strip_suffix(".dll.lib") {
file_name_str = Cow::Owned(s.to_owned() + ".lib");
}
let output_path = target_path.join(file_name_str.as_ref());
file.unpack(output_path.as_path())?;
}
}
}
}
Ok(())
}
fn main() {
println!("cargo:rerun-if-env-changed=WINPRINT_PDFIUM_BUILD_ID");
if std::env::var("DOCS_RS").is_ok() {
return;
}
let target_windows = env::var("CARGO_CFG_TARGET_OS").unwrap();
if target_windows == "windows" {
#[cfg(feature = "pdfium")]
try_link_pdfium().unwrap();
}
}