[fix] make sure Cert#tbs_bytes is up-to-date

src/main/java/org/jruby/ext/openssl/X509Cert.java

@@ -55,13 +55,20 @@
 
 import org.bouncycastle.asn1.ASN1Encodable;
 import org.bouncycastle.asn1.ASN1EncodableVector;
+import org.bouncycastle.asn1.ASN1Encoding;
+import org.bouncycastle.asn1.ASN1Integer;
 import org.bouncycastle.asn1.ASN1ObjectIdentifier;
+import org.bouncycastle.asn1.ASN1Primitive;
 import org.bouncycastle.asn1.ASN1Sequence;
 import org.bouncycastle.asn1.DLSequence;
+import org.bouncycastle.asn1.DERTaggedObject;
 import org.bouncycastle.asn1.x509.GeneralName;
 import org.bouncycastle.asn1.x509.GeneralNames;
 
 import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
+import org.bouncycastle.asn1.x509.TBSCertificate;
+import org.bouncycastle.asn1.x509.Time;
+import org.bouncycastle.asn1.x509.Validity;
 import org.bouncycastle.cert.X509CertificateHolder;
 import org.bouncycastle.cert.X509v3CertificateBuilder;
 import org.bouncycastle.operator.ContentSigner;
@@ -352,14 +359,57 @@ public IRubyObject tbs_bytes() {
         if ( cert == null ) {
             throw newCertificateError(getRuntime(), "no certificate");
         }
+
+        final SubjectPublicKeyInfo publicKeyInfo;
         try {
-            return StringHelper.newString(getRuntime(), cert.getTBSCertificate());
+            publicKeyInfo = SubjectPublicKeyInfo.getInstance(ASN1Primitive.fromByteArray(getPublicKey().getEncoded()));
         }
-        catch (CertificateEncodingException ex) {
+        catch (Exception e) {
+            throw newCertificateError(getRuntime(), "invalid public key data", e);
+        }
+
+        try {
+            return StringHelper.newString(getRuntime(), buildTBSCertificate(publicKeyInfo));
+        }
+        catch (IOException|CertificateEncodingException ex) {
             throw newCertificateError(getRuntime(), ex);
         }
     }
 
+    private byte[] buildTBSCertificate(final SubjectPublicKeyInfo publicKeyInfo)
+        throws IOException, CertificateEncodingException {
+
+        final TBSCertificate certTBS =
+            new X509CertificateHolder(cert.getEncoded()).toASN1Structure().getTBSCertificate();
+
+        final int version = this.version == null ? 0 : RubyNumeric.fix2int(this.version);
+        final ASN1EncodableVector vec = new ASN1EncodableVector(10);
+        if ( version != 0 ) vec.add(new DERTaggedObject(true, 0, new ASN1Integer(version)));
+        vec.add(new ASN1Integer(serial));
+        vec.add(certTBS.getSignature());
+        vec.add(issuer == null ? certTBS.getIssuer() : ((X509Name) issuer).getX500Name());
+        vec.add(new Validity(
+            new Time(not_before != null ? not_before.getJavaDate() : new Date(0)),
+            new Time(not_after != null ? not_after.getJavaDate() : new Date(0)))
+        );
+        vec.add(subject == null ? certTBS.getSubject() : ((X509Name) subject).getX500Name());
+        vec.add(publicKeyInfo);
+
+        if ( certTBS.getIssuerUniqueId() != null ) {
+            vec.add(new DERTaggedObject(false, 1, certTBS.getIssuerUniqueId()));
+        }
+        if ( certTBS.getSubjectUniqueId() != null ) {
+            vec.add(new DERTaggedObject(false, 2, certTBS.getSubjectUniqueId()));
+        }
+        if ( extensions.size() > 0 ) {
+            final ASN1EncodableVector extVec = new ASN1EncodableVector(extensions.size());
+            for ( X509Extension ext : extensions ) extVec.add(ext.toASN1Sequence());
+            vec.add(new DERTaggedObject(true, 3, new DLSequence(extVec)));
+        }
+
+        return new DLSequence(vec).getEncoded(ASN1Encoding.DER);
+    }
+
     @Override
     @JRubyMethod(name = "==")
     public IRubyObject op_equal(ThreadContext context, IRubyObject obj) {
@@ -613,7 +663,9 @@ public IRubyObject set_public_key(IRubyObject public_key) {
     }
 
     private PublicKey getPublicKey() {
-        if ( public_key == null ) initializePublicKey();
+        if (public_key == null) {
+            return cert.getPublicKey();
+        }
         return public_key.getPublicKey();
     }
 

src/test/ruby/x509/test_x509cert.rb

@@ -494,6 +494,61 @@ def test_tbs_precert_bytes
     assert_equal 7, seq.value.size
   end
 
+  def test_tbs_bytes_reflects_current_extensions
+    ca = OpenSSL::X509::Name.parse('/DC=org/DC=ruby-lang/CN=CA')
+    cert = issue_cert(ca, OpenSSL::PKey::RSA.new(TEST_KEY_RSA1024), 1,
+                      [['basicConstraints', 'CA:TRUE', true]], nil, nil)
+
+    assert_equal 8, OpenSSL::ASN1.decode(cert.tbs_bytes).value.size
+
+    cert.extensions = []
+    seq = OpenSSL::ASN1.decode(cert.tbs_bytes)
+
+    assert_equal 7, seq.value.size
+    assert_equal false, seq.value.any? { |val| val.tag_class == :CONTEXT_SPECIFIC && val.tag == 3 }
+  end
+
+  def test_tbs_bytes_reflects_extensions_removal
+    cert = File.expand_path('digicert.pem', File.dirname(__FILE__))
+    cert = OpenSSL::X509::Certificate.new(File.read(cert))
+
+    assert cert.extensions.size > 1
+    original = cert.tbs_bytes
+
+    dup = cert.dup
+    removed_oid = cert.extensions.first.oid
+    dup.extensions = dup.extensions.reject { |ext| ext.oid == removed_oid }
+
+    mutated = dup.tbs_bytes
+    refute_equal original, mutated, 'tbs_bytes must reflect extensions= mutation'
+    assert mutated.bytesize < original.bytesize, 'removing an extension must shrink tbs_bytes'
+
+    expected = cert.extensions.map(&:oid).reject { |oid| oid == removed_oid }
+                   .map { |oid| OpenSSL::ASN1::ObjectId.new(oid).oid } # OID name -> identifier
+    assert_equal expected, tbs_extension_oids(mutated)
+  end
+
+  # Extract the extension OIDs (in order) from a DER-encoded TBSCertificate
+  def tbs_extension_oids(tbs_der)
+    tbs = OpenSSL::ASN1.decode(tbs_der)
+    assert_equal OpenSSL::ASN1::Sequence, tbs.class
+
+    holder = tbs.value.find do |e|
+      e.respond_to?(:tag) && e.tag == 3 && e.tag_class == :CONTEXT_SPECIFIC
+    end
+
+    holder ? holder.value[0].value.map { |ext| ext.value[0].oid } : []
+  end
+
+  def test_tbs_bytes_unchanged_after_assigning_same_extensions
+    cert = File.expand_path('digicert.pem', File.dirname(__FILE__))
+    cert = OpenSSL::X509::Certificate.new(File.read(cert))
+
+    dup = cert.dup
+    dup.extensions = dup.extensions # reassign the same set
+    assert_equal cert.tbs_bytes, dup.tbs_bytes
+  end
+
   def test_eq
     now = Time.now
     ca = OpenSSL::X509::Name.parse('/DC=org/DC=ruby-lang/CN=CA')