Check whether or not a certificate is self-signed.

net/cert/x509_certificate_nss.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/cert/x509_certificate.h"
 
 #include <cert.h>
 #include <cryptohi.h>
 #include <keyhi.h>
 #include <nss.h>
@@ skipping 248 matching lines @@
       cert_handle->derCert.len);
 }
 
 // static
 void X509Certificate::GetPublicKeyInfo(OSCertHandle cert_handle,
                                        size_t* size_bits,
                                        PublicKeyType* type) {
   x509_util::GetPublicKeyInfo(cert_handle, size_bits, type);
 }
 
+// static
+bool X509Certificate::IsSelfSigned(OSCertHandle cert_handle) {
+  SECKEYPublicKey* public_key = CERT_ExtractPublicKey(cert_handle);
+  if (!public_key)
+    return false;
+
+  SECStatus verified = CERT_VerifySignedDataWithPublicKey(
+      &cert_handle->signatureWrap, public_key, NULL);
+  return verified == SECSuccess;
+}
+
 }  // namespace net