Let clients list and revoke certs

protos/ezshare.proto

@@ -135,3 +135,27 @@ service UserService {
     rpc Approve(ApproveUserRequest) returns (Empty) {}
     rpc ChangePassword(ChangePasswordRequest) returns (Empty) {}
 }
+
+///////////////////////////////
+// Certificate related stuff //
+///////////////////////////////
+
+// List
+message ListCertificatesResponse {
+    message CertificateInfo {
+        string serial = 1;
+        string owner_id = 2;
+        string owner_username = 3;
+    }
+    repeated CertificateInfo certificates = 1;
+}
+
+// Revoke
+message RevokeCertificateRequest {
+    string serial = 1;
+}
+
+service CertificateService {
+    rpc ListCertificates(Empty) returns (ListCertificatesResponse) {}
+    rpc RevokeCertificate(RevokeCertificateRequest) returns (Empty) {}
+}