Add an example of making a CA and certs and verifying.

openssl/examples/mk_certs.rs

@@ -0,0 +1,153 @@
+//! A program that generates ca certs, certs verified by the ca, and public
+//! and private keys.
+
+extern crate openssl;
+
+use openssl::asn1::Asn1Time;
+use openssl::bn::BigNum;
+use openssl::error::ErrorStack;
+use openssl::hash::MessageDigest;
+use openssl::pkey::{PKey, PKeyRef};
+use openssl::rand::rand_bytes;
+use openssl::rsa::Rsa;
+use openssl::x509::{X509, X509Ref};
+use openssl::x509::{X509NameBuilder, X509Req, X509ReqBuilder};
+use openssl::x509::extension::{AuthorityKeyIdentifier, BasicConstraints, KeyUsage,
+                               SubjectAlternativeName, SubjectKeyIdentifier};
+
+/// Make a CA certificate and private key
+fn mk_ca_cert() -> Result<(X509, PKey), ErrorStack> {
+    let rsa = Rsa::generate(2048)?;
+    let privkey = PKey::from_rsa(rsa)?;
+
+    let mut x509_name = X509NameBuilder::new()?;
+    x509_name.append_entry_by_text("C", "US")?;
+    x509_name.append_entry_by_text("ST", "TX")?;
+    x509_name.append_entry_by_text("O", "Some CA organization")?;
+    x509_name.append_entry_by_text("CN", "ca test")?;
+    let x509_name = x509_name.build();
+
+    let mut cert_builder = X509::builder()?;
+    cert_builder.set_version(2)?;
+    let serial_number = {
+        let mut buf = [0;20];
+        rand_bytes(&mut buf)?;
+        BigNum::from_slice(&buf)?.to_asn1_integer()?
+    };
+    cert_builder.set_serial_number(&serial_number)?;
+    cert_builder.set_subject_name(&x509_name)?;
+    cert_builder.set_issuer_name(&x509_name)?;
+    cert_builder.set_pubkey(&privkey)?;
+    let not_before = Asn1Time::days_from_now(0)?;
+    cert_builder.set_not_before(&not_before)?;
+    let not_after = Asn1Time::days_from_now(365)?;
+    cert_builder.set_not_after(&not_after)?;
+
+    cert_builder.append_extension(BasicConstraints::new().critical().ca().build()?)?;
+    cert_builder.append_extension(KeyUsage::new()
+        .critical()
+        .key_cert_sign()
+        .crl_sign()
+        .build()?)?;
+
+    let subject_key_identifier =
+        SubjectKeyIdentifier::new().build(&cert_builder.x509v3_context(None, None))?;
+    cert_builder.append_extension(subject_key_identifier)?;
+
+    cert_builder.sign(&privkey, MessageDigest::sha256())?;
+    let cert = cert_builder.build();
+
+    Ok((cert, privkey))
+}
+
+/// Make a X509 request with the given private key
+fn mk_request(privkey: &PKey) -> Result<(X509Req), ErrorStack> {
+    let mut req_builder = X509ReqBuilder::new()?;
+    req_builder.set_pubkey(&privkey)?;
+
+    let mut x509_name = X509NameBuilder::new()?;
+    x509_name.append_entry_by_text("C", "US")?;
+    x509_name.append_entry_by_text("ST", "TX")?;
+    x509_name.append_entry_by_text("O", "Some organization")?;
+    x509_name.append_entry_by_text("CN", "www.example.com")?;
+    let x509_name = x509_name.build();
+    req_builder.set_subject_name(&x509_name)?;
+
+    req_builder.sign(&privkey, MessageDigest::sha256())?;
+    let req = req_builder.build();
+    Ok(req)
+}
+
+/// Make a certificate and private key signed by the given CA cert and private key
+fn mk_ca_signed_cert(ca_cert: &X509Ref, ca_privkey: &PKeyRef) -> Result<(X509, PKey), ErrorStack> {
+    let rsa = Rsa::generate(2048)?;
+    let privkey = PKey::from_rsa(rsa)?;
+
+    let req = mk_request(&privkey)?;
+
+    let mut cert_builder = X509::builder()?;
+    cert_builder.set_version(2)?;
+    let serial_number = {
+        let mut buf = [0;20];
+        rand_bytes(&mut buf)?;
+        BigNum::from_slice(&buf)?.to_asn1_integer()?
+    };
+    cert_builder.set_serial_number(&serial_number)?;
+    cert_builder.set_subject_name(req.subject_name())?;
+    cert_builder.set_issuer_name(ca_cert.subject_name())?;
+    cert_builder.set_pubkey(&privkey)?;
+    let not_before = Asn1Time::days_from_now(0)?;
+    cert_builder.set_not_before(&not_before)?;
+    let not_after = Asn1Time::days_from_now(365)?;
+    cert_builder.set_not_after(&not_after)?;
+
+    cert_builder.append_extension(BasicConstraints::new().build()?)?;
+
+    cert_builder.append_extension(KeyUsage::new()
+        .critical()
+        .non_repudiation()
+        .digital_signature()
+        .key_encipherment()
+        .build()?)?;
+
+    let subject_key_identifier = SubjectKeyIdentifier::new()
+        .build(&cert_builder.x509v3_context(Some(ca_cert), None))?;
+    cert_builder.append_extension(subject_key_identifier)?;
+
+    let auth_key_identifier = AuthorityKeyIdentifier::new()
+        .keyid(false)
+        .issuer(false)
+        .build(&cert_builder.x509v3_context(Some(ca_cert), None))?;
+    cert_builder.append_extension(auth_key_identifier)?;
+
+    let subject_alt_name = SubjectAlternativeName::new()
+        .dns("*.example.com")
+        .dns("hello.com")
+        .build(&cert_builder.x509v3_context(Some(ca_cert), None))?;
+    cert_builder.append_extension(subject_alt_name)?;
+
+    cert_builder.sign(&ca_privkey, MessageDigest::sha256())?;
+    let cert = cert_builder.build();
+
+    Ok((cert, privkey))
+}
+
+fn real_main() -> Result<(), ErrorStack> {
+    let (ca_cert, ca_privkey) = mk_ca_cert()?;
+    let (cert, _privkey) = mk_ca_signed_cert(&ca_cert, &ca_privkey)?;
+
+    // Verify that this cert was issued by this ca
+    match ca_cert.issued(&cert) {
+        Err(ver_err) => println!("Failed to verify certificate: {}", ver_err),
+        Ok(()) => println!("Certificate verified!"),
+    };
+
+    Ok(())
+}
+
+fn main() {
+    match real_main() {
+        Ok(()) => println!("Finished."),
+        Err(e) => println!("Error: {}", e),
+    };
+}