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use {
anyhow::{anyhow, Result},
chrono::SubsecRound,
std::{
io::Read,
path::{Path, PathBuf},
},
};
#[derive(Clone, Debug)]
pub struct FileBasedX509SigningCertificate {
path: PathBuf,
password: Option<String>,
}
impl FileBasedX509SigningCertificate {
pub fn new(path: impl AsRef<Path>) -> Self {
Self {
path: path.as_ref().to_path_buf(),
password: None,
}
}
pub fn path(&self) -> &Path {
&self.path
}
pub fn password(&self) -> &Option<String> {
&self.password
}
pub fn set_password(&mut self, password: impl ToString) {
self.password = Some(password.to_string());
}
}
#[derive(Clone, Debug)]
pub enum X509SigningCertificate {
Auto,
File(FileBasedX509SigningCertificate),
SubjectName(String),
}
impl From<FileBasedX509SigningCertificate> for X509SigningCertificate {
fn from(v: FileBasedX509SigningCertificate) -> Self {
Self::File(v)
}
}
pub fn create_self_signed_code_signing_certificate_params(
subject_name: &str,
) -> rcgen::CertificateParams {
let mut params = rcgen::CertificateParams::new(vec![]);
params.alg = &rcgen::PKCS_ECDSA_P256_SHA256;
params.key_identifier_method = rcgen::KeyIdMethod::Sha256;
params.distinguished_name = rcgen::DistinguishedName::new();
params
.subject_alt_names
.push(rcgen::SanType::DnsName(subject_name.to_string()));
params
.distinguished_name
.push(rcgen::DnType::CommonName, subject_name);
params
.extended_key_usages
.push(rcgen::ExtendedKeyUsagePurpose::CodeSigning);
params.is_ca = rcgen::IsCa::Ca(rcgen::BasicConstraints::Unconstrained);
params.not_after = chrono::Utc::now()
.checked_add_signed(chrono::Duration::days(365))
.unwrap()
.trunc_subsecs(0);
let mut key_usage =
rcgen::CustomExtension::from_oid_content(&[2, 5, 29, 15], vec![3, 2, 7, 128]);
key_usage.set_criticality(true);
params.custom_extensions.push(key_usage);
params
}
pub fn create_self_signed_code_signing_certificate(
subject_name: &str,
) -> std::result::Result<rcgen::Certificate, rcgen::RcgenError> {
let params = create_self_signed_code_signing_certificate_params(subject_name);
rcgen::Certificate::from_params(params)
}
pub fn certificate_to_pfx(
cert: &rcgen::Certificate,
password: &str,
name: &str,
) -> Result<Vec<u8>> {
let cert_der = cert.serialize_der()?;
let key_der = cert.serialize_private_key_der();
let pfx = p12::PFX::new(&cert_der, &key_der, None, password, name)
.ok_or_else(|| anyhow!("unable to convert to pfx"))?;
let buffer = yasna::construct_der(|writer| {
pfx.write(writer);
});
Ok(buffer)
}
const CFB_MAGIC_NUMBER: [u8; 8] = [0xd0, 0xcf, 0x11, 0xe0, 0xa1, 0xb1, 0x1a, 0xe1];
#[allow(clippy::if_same_then_else)]
pub fn is_signable_binary_header(data: &[u8]) -> bool {
if data.len() < 16 {
false
} else if data[0] == 0x4d && data[1] == 0x5a {
true
} else {
data[0..CFB_MAGIC_NUMBER.len()] == CFB_MAGIC_NUMBER
}
}
pub fn is_file_signable(path: impl AsRef<Path>) -> Result<bool> {
let path = path.as_ref();
if path.metadata()?.len() < 16 {
return Ok(false);
}
let mut fh = std::fs::File::open(&path)?;
let mut buffer: [u8; 16] = [0; 16];
fh.read_exact(&mut buffer)?;
Ok(is_signable_binary_header(&buffer))
}
#[cfg(test)]
mod tests {
use {
super::*,
anyhow::Result,
der_parser::oid,
std::{collections::BTreeMap, iter::FromIterator},
};
const POWERSHELL_CERTIFICATE_PUBLIC_PEM: &str = "-----BEGIN CERTIFICATE-----\n\
MIIBnzCCAUagAwIBAgIQSE/jLE4ZZYtHZ1e/Uh5IKTAKBggqhkjOPQQDAjAeMRww\n\
GgYDVQQDDBN0ZXN0aW5nQGV4YW1wbGUuY29tMB4XDTIwMTEyNjIxMjIyOFoXDTIx\n\
MTEyNjIxNDIyOFowHjEcMBoGA1UEAwwTdGVzdGluZ0BleGFtcGxlLmNvbTBZMBMG\n\
ByqGSM49AgEGCCqGSM49AwEHA0IABG50cCwrBbSYIHjakucfkFQwBxyELaqq36a5\n\
l33+zC5ugnh/zDNp/txhOEHoWb7KxgeeLsDU5fnE5o7LWMweHF6jZjBkMA4GA1Ud\n\
DwEB/wQEAwIHgDATBgNVHSUEDDAKBggrBgEFBQcDAzAeBgNVHREEFzAVghN0ZXN0\n\
aW5nQGV4YW1wbGUuY29tMB0GA1UdDgQWBBQTIsJVQaqqlRroqvxjrQxdaPWF2zAK\n\
BggqhkjOPQQDAgNHADBEAiBW6XrjErz6HAyJk/lhyhAfpYiQBKc+74dBaBFRccbd\n\
HgIgWCs4HPGhR1KmUEvjOLZLxsph/SZ1omQt8QQQYsUn1m4=\n\
-----END CERTIFICATE-----\n";
const POWERSHELL_CERTIFICATE_PRIVATE_PEM: &str = "-----BEGIN PRIVATE KEY-----\n\
MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQg9mPzM4rZBqtjLuWZ\n\
rWiPM5PgwTcsYMm6ojX9OAz1AIehRANCAARudHAsKwW0mCB42pLnH5BUMAcchC2q\n\
qt+muZd9/swuboJ4f8wzaf7cYThB6Fm+ysYHni7A1OX5xOaOy1jMHhxe\n\
-----END PRIVATE KEY-----\n";
#[test]
fn test_create_self_signed_certificate() -> Result<()> {
let powershell_pem = x509_parser::pem::Pem::read(std::io::Cursor::new(
POWERSHELL_CERTIFICATE_PUBLIC_PEM.as_bytes(),
))?
.0;
let powershell = powershell_pem.parse_x509()?;
rcgen::KeyPair::from_pem(POWERSHELL_CERTIFICATE_PRIVATE_PEM)?;
let cert = create_self_signed_code_signing_certificate("testing@example.com")?;
let cert_der = cert.serialize_der()?;
let generated = x509_parser::parse_x509_certificate(&cert_der)?.1;
assert_eq!(generated.subject(), powershell.subject(), "subject matches");
assert_eq!(
generated.signature_algorithm, powershell.signature_algorithm,
"signature algorithm matches"
);
let subject_key_identifier_oid = oid!(2.5.29 .14);
let basic_constraints_oid = oid!(2.5.29 .19);
let subject_alternative_name_oid = oid!(2.5.29 .17);
let extended_usage_oid = oid!(2.5.29 .37);
let key_usage_oid = oid!(2.5.29 .15);
assert!(generated
.extensions()
.contains_key(&subject_key_identifier_oid));
assert_ne!(
generated.extensions().get(&subject_key_identifier_oid),
powershell.extensions().get(&subject_key_identifier_oid),
"subject key identifier extension differs"
);
assert!(generated.extensions().contains_key(&basic_constraints_oid));
assert!(!powershell.extensions().contains_key(&basic_constraints_oid));
assert!(generated
.extensions()
.contains_key(&subject_alternative_name_oid));
assert_eq!(
generated.extensions().get(&subject_alternative_name_oid),
powershell.extensions().get(&subject_alternative_name_oid),
"subject alternative name extension identical"
);
assert!(generated.extensions().contains_key(&extended_usage_oid));
assert_eq!(
generated.extensions().get(&extended_usage_oid),
powershell.extensions().get(&extended_usage_oid),
"extended key usage extension identical"
);
assert!(generated.extensions().contains_key(&key_usage_oid));
assert_eq!(
generated.extensions().get(&key_usage_oid),
powershell.extensions().get(&key_usage_oid),
"key usage extension identical"
);
let generated_filtered =
BTreeMap::from_iter(generated.extensions().iter().filter_map(|(k, ext)| {
if k != &subject_key_identifier_oid && k != &basic_constraints_oid {
Some((k.to_id_string(), ext.clone()))
} else {
None
}
}));
let powershell_filtered =
BTreeMap::from_iter(powershell.extensions().iter().filter_map(|(k, ext)| {
if k != &subject_key_identifier_oid {
Some((k.to_id_string(), ext.clone()))
} else {
None
}
}));
assert_eq!(generated_filtered, powershell_filtered, "extensions match");
Ok(())
}
#[test]
fn test_serialize_pfx() -> Result<()> {
let cert = create_self_signed_code_signing_certificate("someone@example.com")?;
certificate_to_pfx(&cert, "password", "name")?;
Ok(())
}
#[test]
fn test_is_signable() -> Result<()> {
let exe = std::env::current_exe()?;
let is_signable = is_file_signable(&exe)?;
if cfg!(target_family = "windows") {
assert!(is_signable);
} else {
assert!(!is_signable);
}
Ok(())
}
}