diff --git a/base/fakesslidentity.h b/base/fakesslidentity.h
index 69d590b..ec603a5 100644
--- a/base/fakesslidentity.h
+++ b/base/fakesslidentity.h
@@ -25,9 +25,11 @@
   // SHA-1 is the default digest algorithm because it is available in all build
   // configurations used for unit testing.
   explicit FakeSSLCertificate(const std::string& data)
-      : data_(data), digest_algorithm_(DIGEST_SHA_1) {}
+      : data_(data), digest_algorithm_(DIGEST_SHA_1), expiration_time_(-1) {}
   explicit FakeSSLCertificate(const std::vector<std::string>& certs)
-      : data_(certs.front()), digest_algorithm_(DIGEST_SHA_1) {
+      : data_(certs.front()),
+        digest_algorithm_(DIGEST_SHA_1),
+        expiration_time_(-1) {
     std::vector<std::string>::const_iterator it;
     // Skip certs[0].
     for (it = certs.begin() + 1; it != certs.end(); ++it) {
@@ -45,7 +47,12 @@
     VERIFY(SSLIdentity::PemToDer(kPemTypeCertificate, data_, &der_string));
     der_buffer->SetData(der_string.c_str(), der_string.size());
   }
-  int64_t CertificateExpirationTime() const override { return -1; }
+  int64_t CertificateExpirationTime() const override {
+    return expiration_time_;
+  }
+  void SetCertificateExpirationTime(int64_t expiration_time) {
+    expiration_time_ = expiration_time;
+  }
   void set_digest_algorithm(const std::string& algorithm) {
     digest_algorithm_ = algorithm;
   }
@@ -79,6 +86,8 @@
   std::string data_;
   std::vector<FakeSSLCertificate> certs_;
   std::string digest_algorithm_;
+  // Expiration time in seconds relative to epoch, 1970-01-01T00:00:00Z (UTC).
+  int64_t expiration_time_;
 };
 
 class FakeSSLIdentity : public rtc::SSLIdentity {