Fail authentication instead of closing connection when try to authori…

…ze with empty user name or password. (cosullivan#65)
dosper7 · May 29, 2018 · 58555f1 · 58555f1
1 parent 89edf00
commit 58555f1
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Showing 2 changed files with 30 additions and 1 deletion.
diff --git a/Src/SmtpServer.Tests/SmtpServerTests.cs b/Src/SmtpServer.Tests/SmtpServerTests.cs
@@ -87,6 +87,35 @@ public void CanAuthenticateUser()
             }
         }
 
+        [Theory]
+        [InlineData("",     ""        )]
+        [InlineData("user", ""        )]
+        [InlineData("",     "password")]
+        public void CanFailAuthenticationEmptyUserOrPassword(string user, string password)
+        {
+            // arrange
+            string actualUser = null;
+            string actualPassword = null;
+            var userAuthenticator = new DelegatingUserAuthenticator((u, p) =>
+            {
+                actualUser = u;
+                actualPassword = p;
+
+                return false;
+            });
+
+            using (CreateServer(options => options.AllowUnsecureAuthentication().UserAuthenticator(userAuthenticator)))
+            {
+                // act and assert
+                Assert.Throws<MailKit.Security.AuthenticationException>(() => MailClient.Send(user: user, password: password));
+
+                // assert
+                Assert.Equal(0, MessageStore.Messages.Count);
+                Assert.Equal(user, actualUser);
+                Assert.Equal(password, actualPassword);
+            }
+        }
+
         [Fact]
         public void CanReceiveBccInMessageTransaction()
         {

diff --git a/Src/SmtpServer/Protocol/AuthCommand.cs b/Src/SmtpServer/Protocol/AuthCommand.cs
@@ -157,7 +157,7 @@ async Task<string> ReadBase64EncodedLineAsync(INetworkClient client, Cancellatio
         {
             var text = await client.ReadLineAsync(Encoding.ASCII, cancellationToken).ReturnOnAnyThread();
 
-            return Encoding.UTF8.GetString(Convert.FromBase64String(text));
+            return Encoding.UTF8.GetString(Convert.FromBase64String(text ?? ""));
         }
 
         /// <summary>