Merge pull request #217 from mjcheetham/ntlm-proxy-auth

Treat empty credential proxy configuration as use system default credentials

Author: mjcheetham

src/shared/Microsoft.Git.CredentialManager.Tests/HttpClientFactoryTests.cs

@@ -118,6 +118,104 @@ public void HttpClientFactory_TryCreateProxy_ProxyWithCredentials_ReturnsTrueOut
             Assert.Equal(proxyPass, configuredCredentials.Password);
         }
 
+        [Fact]
+        public void HttpClientFactory_TryCreateProxy_ProxyWithNonEmptyUserAndEmptyPass_ReturnsTrueOutProxyWithUrlConfiguredCredentials()
+        {
+            const string proxyScheme = "https";
+            const string proxyUser   = "john.doe";
+            const string proxyHost   = "proxy.example.com/git";
+            const string repoPath    = "/tmp/repos/foo";
+            const string repoRemote  = "https://remote.example.com/foo.git";
+
+            string proxyConfigString = $"{proxyScheme}://{proxyUser}:@{proxyHost}";
+            string expectedProxyUrl  = $"{proxyScheme}://{proxyHost}";
+            var repoRemoteUri = new Uri(repoRemote);
+
+            var settings = new TestSettings
+            {
+                RemoteUri = repoRemoteUri,
+                RepositoryPath = repoPath,
+                ProxyConfiguration = new Uri(proxyConfigString)
+            };
+            var httpFactory = new HttpClientFactory(Mock.Of<ITrace>(), settings, Mock.Of<IStandardStreams>());
+
+            bool result = httpFactory.TryCreateProxy(out IWebProxy proxy);
+
+            Assert.True(result);
+            Assert.NotNull(proxy);
+            var configuredProxyUrl = proxy.GetProxy(repoRemoteUri);
+            Assert.Equal(expectedProxyUrl, configuredProxyUrl.ToString());
+
+            Assert.NotNull(proxy.Credentials);
+            Assert.IsType<NetworkCredential>(proxy.Credentials);
+            var configuredCredentials = (NetworkCredential) proxy.Credentials;
+            Assert.Equal(proxyUser, configuredCredentials.UserName);
+            Assert.True(string.IsNullOrWhiteSpace(configuredCredentials.Password));
+        }
+
+        [Fact]
+        public void HttpClientFactory_TryCreateProxy_ProxyWithEmptyUserAndNonEmptyPass_ReturnsTrueOutProxyWithUrlConfiguredCredentials()
+        {
+            const string proxyScheme = "https";
+            const string proxyPass   = "letmein";
+            const string proxyHost   = "proxy.example.com/git";
+            const string repoPath    = "/tmp/repos/foo";
+            const string repoRemote  = "https://remote.example.com/foo.git";
+
+            string proxyConfigString = $"{proxyScheme}://:{proxyPass}@{proxyHost}";
+            string expectedProxyUrl  = $"{proxyScheme}://{proxyHost}";
+            var repoRemoteUri = new Uri(repoRemote);
+
+            var settings = new TestSettings
+            {
+                RemoteUri = repoRemoteUri,
+                RepositoryPath = repoPath,
+                ProxyConfiguration = new Uri(proxyConfigString)
+            };
+            var httpFactory = new HttpClientFactory(Mock.Of<ITrace>(), settings, Mock.Of<IStandardStreams>());
+
+            bool result = httpFactory.TryCreateProxy(out IWebProxy proxy);
+
+            Assert.True(result);
+            Assert.NotNull(proxy);
+            var configuredProxyUrl = proxy.GetProxy(repoRemoteUri);
+            Assert.Equal(expectedProxyUrl, configuredProxyUrl.ToString());
+
+            Assert.NotNull(proxy.Credentials);
+            Assert.IsType<NetworkCredential>(proxy.Credentials);
+            var configuredCredentials = (NetworkCredential) proxy.Credentials;
+            Assert.True(string.IsNullOrWhiteSpace(configuredCredentials.UserName));
+            Assert.Equal(proxyPass, configuredCredentials.Password);
+        }
+
+        [Fact]
+        public void HttpClientFactory_TryCreateProxy_ProxyEmptyUserAndEmptyPass_ReturnsTrueOutProxyWithUrlDefaultCredentials()
+        {
+            const string repoPath = "/tmp/repos/foo";
+            const string repoRemote = "https://remote.example.com/foo.git";
+            var repoRemoteUri = new Uri(repoRemote);
+
+            string proxyConfigString = "https://:@proxy.example.com/git";
+            string expectedProxyUrl = "https://proxy.example.com/git";
+
+            var settings = new TestSettings
+            {
+                RemoteUri = repoRemoteUri,
+                RepositoryPath = repoPath,
+                ProxyConfiguration = new Uri(proxyConfigString)
+            };
+            var httpFactory = new HttpClientFactory(Mock.Of<ITrace>(), settings, Mock.Of<IStandardStreams>());
+
+            bool result = httpFactory.TryCreateProxy(out IWebProxy proxy);
+
+            Assert.True(result);
+            Assert.NotNull(proxy);
+            var configuredProxyUrl = proxy.GetProxy(repoRemoteUri);
+            Assert.Equal(expectedProxyUrl, configuredProxyUrl.ToString());
+
+            AssertDefaultCredentials(proxy.Credentials);
+        }
+
         private static void AssertDefaultCredentials(ICredentials credentials)
         {
             var netCred = (NetworkCredential) credentials;

src/shared/Microsoft.Git.CredentialManager/HttpClientFactory.cs

@@ -120,24 +120,30 @@ public bool TryCreateProxy(out IWebProxy proxy)
                 // Dictionary of proxy info for tracing
                 var dict = new Dictionary<string, string> {["uri"] = proxyUri.ToString()};
 
-                // Try to extract and configure proxy credentials from the configured URI
-                if (proxyConfig.TryGetUserInfo(out string userName, out string password))
+                // Try to extract and configure proxy credentials from the configured URI.
+                // For an empty username AND password we should use the system default credentials
+                // (for example for Windows Integrated Authentication-based proxies).
+                if (proxyConfig.TryGetUserInfo(out string userName, out string password) &&
+                    !(string.IsNullOrEmpty(userName) && string.IsNullOrEmpty(password)))
                 {
                     proxy = new WebProxy(proxyUri)
                     {
                         Credentials = new NetworkCredential(userName, password)
                     };
 
                     // Add user/pass info to the trace dictionary
-                    if (!string.IsNullOrWhiteSpace(userName)) dict["username"] = userName;
-                    if (!string.IsNullOrEmpty(password))      dict["password"] = password;
+                    dict["username"] = userName;
+                    dict["password"] = password;
                 }
                 else
                 {
                     proxy = new WebProxy(proxyUri)
                     {
                         UseDefaultCredentials = true
                     };
+
+                    // Trace the use of system default credentials
+                    dict["useDefaultCredentials"] = "true";
                 }
 
                 // Tracer out proxy info dictionary