Function is_self_signed

crates/stdlib/src/ssl/cert.rs:1627–1639

Check if a certificate is self-signed by comparing issuer and subject. Returns true if the certificate is self-signed (issuer == subject).

(cert_der: &CertificateDer<'_>)

/// Check if a certificate is self-signed by comparing issuer and subject.
/// Returns true if the certificate is self-signed (issuer == subject).
fn is_self_signed(cert_der: &CertificateDer<'_>) -> bool {
    use x509_parser::prelude::*;

    // Parse the certificate
    let Ok((_, cert)) = X509Certificate::from_der(cert_der.as_ref()) else {
        // If we can't parse it, assume it's not self-signed (conservative approach)
        return false;
    };

    // Compare issuer and subject
    // A certificate is self-signed if issuer == subject
    cert.issuer() == cert.subject()
}

/// Verify that a certificate is valid for the given hostname/IP address.
/// This function checks Subject Alternative Names (SAN) and Common Name (CN).