public override async Task <ICredential> GenerateCredentialAsync(InputArguments input)
{
ThrowIfDisposed();
Uri uri = input.GetRemoteUri();
// Determine the if the host supports Windows Integration Authentication (WIA)
if (IsWindowsAuthAllowed)
{
if (PlatformUtils.IsWindows())
{
Context.Trace.WriteLine($"Checking host '{uri.AbsoluteUri}' for Windows Integrated Authentication...");
bool isWiaSupported = await _winAuth.GetIsSupportedAsync(uri);
if (!isWiaSupported)
{
Context.Trace.WriteLine("Host does not support WIA.");
}
else
{
Context.Trace.WriteLine("Host supports WIA - generating empty credential...");
// WIA is signaled to Git using an empty username/password
return(new GitCredential(string.Empty, string.Empty));
}
}
else
{
string osType = PlatformUtils.GetPlatformInformation().OperatingSystemType;
Context.Trace.WriteLine($"Skipping check for Windows Integrated Authentication on {osType}.");
}
}
else
{
Context.Trace.WriteLine("Windows Integrated Authentication detection has been disabled.");
}
Context.Trace.WriteLine("Prompting for basic credentials...");
return(_basicAuth.GetCredentials(uri.AbsoluteUri, input.UserName));
}
/// <summary>
/// Return a string that uniquely identifies the service that a credential should be stored against.
/// </summary>
/// <remarks>
/// <para>
/// This key forms part of the identifier used to retrieve and store credentials from the OS secure
/// credential storage system. It is important the returned value is stable over time to avoid any
/// potential re-authentication requests.
/// </para>
/// <para>
/// The default implementation returns the absolute URI formed by from the <see cref="InputArguments"/>
/// without any userinfo component. Any trailing slashes are trimmed.
/// </para>
/// </remarks>
/// <param name="input">Input arguments of a Git credential query.</param>
/// <returns>Credential service name.</returns>
public virtual string GetServiceName(InputArguments input)
{
// By default we assume the service name will be the absolute URI based on the
// input arguments from Git, without any userinfo part.
return(input.GetRemoteUri(includeUser: false).AbsoluteUri.TrimEnd('/'));
}
public async Task <IHostProvider> GetProviderAsync(InputArguments input)
{
IHostProvider provider;
//
// Try and locate a specified provider
//
if (_context.Settings.ProviderOverride is string providerId)
{
_context.Trace.WriteLine($"Host provider override was set id='{providerId}'");
if (!StringComparer.OrdinalIgnoreCase.Equals(Constants.ProviderIdAuto, providerId))
{
provider = _hostProviders
.SelectMany(x => x.Value)
.FirstOrDefault(x => StringComparer.OrdinalIgnoreCase.Equals(x.Id, providerId));
if (provider is null)
{
_context.Trace.WriteLine($"No host provider was found with ID '{providerId}'.. falling back to auto-detection.");
_context.Streams.Error.WriteLine($"warning: a host provider override was set but no such provider '{providerId}' was found. Falling back to auto-detection.");
}
else
{
return(provider);
}
}
}
//
// Try and locate a provider by supported authorities
//
else if (_context.Settings.LegacyAuthorityOverride is string authority)
{
_context.Trace.WriteLine($"Host provider authority override was set authority='{authority}'");
_context.Streams.Error.WriteLine("warning: the `credential.authority` and `GCM_AUTHORITY` settings are deprecated.");
_context.Streams.Error.WriteLine($"warning: see {Constants.HelpUrls.GcmAuthorityDeprecated} for more information.");
if (!StringComparer.OrdinalIgnoreCase.Equals(Constants.AuthorityIdAuto, authority))
{
provider = _hostProviders
.SelectMany(x => x.Value)
.FirstOrDefault(x => x.SupportedAuthorityIds.Contains(authority, StringComparer.OrdinalIgnoreCase));
if (provider is null)
{
_context.Trace.WriteLine($"No host provider was found with authority '{authority}'.. falling back to auto-detection.");
_context.Streams.Error.WriteLine($"warning: a supported authority override was set but no such provider supporting authority '{authority}' was found. Falling back to auto-detection.");
}
else
{
return(provider);
}
}
}
//
// Auto-detection
//
_context.Trace.WriteLine("Performing auto-detection of host provider.");
var uri = input.GetRemoteUri();
var queryResponse = new Lazy <Task <HttpResponseMessage> >(() =>
{
_context.Trace.WriteLine("Querying remote URL for host provider auto-detection.");
return(HttpClient.HeadAsync(uri));
});
async Task <IHostProvider> MatchProviderAsync(HostProviderPriority priority)
{
if (_hostProviders.TryGetValue(priority, out ICollection <IHostProvider> providers))
{
_context.Trace.WriteLine($"Checking against {providers.Count} host providers registered with priority '{priority}'.");
// Try matching using the static Git input arguments first (cheap)
if (providers.TryGetFirst(x => x.IsSupported(input), out IHostProvider match))
{
return(match);
}
HttpResponseMessage response = await queryResponse.Value;
// Try matching using the HTTP response from a query to the remote URL (expensive)
if (providers.TryGetFirst(x => x.IsSupported(response), out match))
{
return(match);
}
}
return(null);
}
// Match providers starting with the highest priority
return(await MatchProviderAsync(HostProviderPriority.High) ??
await MatchProviderAsync(HostProviderPriority.Normal) ??
await MatchProviderAsync(HostProviderPriority.Low) ??
throw new Exception("No host provider available to service this request."));
}
public async Task <IHostProvider> GetProviderAsync(InputArguments input)
{
IHostProvider provider;
//
// Try and locate a specified provider
//
if (_context.Settings.ProviderOverride is string providerId)
{
_context.Trace.WriteLine($"Host provider override was set id='{providerId}'");
if (!StringComparer.OrdinalIgnoreCase.Equals(Constants.ProviderIdAuto, providerId))
{
provider = _hostProviders
.SelectMany(x => x.Value)
.FirstOrDefault(x => StringComparer.OrdinalIgnoreCase.Equals(x.Id, providerId));
if (provider is null)
{
_context.Trace.WriteLine($"No host provider was found with ID '{providerId}'.. falling back to auto-detection.");
_context.Streams.Error.WriteLine($"warning: a host provider override was set but no such provider '{providerId}' was found. Falling back to auto-detection.");
}
else
{
return(provider);
}
}
}
//
// Try and locate a provider by supported authorities
//
else if (_context.Settings.LegacyAuthorityOverride is string authority)
{
_context.Trace.WriteLine($"Host provider authority override was set authority='{authority}'");
_context.Streams.Error.WriteLine("warning: the `credential.authority` and `GCM_AUTHORITY` settings are deprecated.");
_context.Streams.Error.WriteLine($"warning: see {Constants.HelpUrls.GcmAuthorityDeprecated} for more information.");
if (!StringComparer.OrdinalIgnoreCase.Equals(Constants.AuthorityIdAuto, authority))
{
provider = _hostProviders
.SelectMany(x => x.Value)
.FirstOrDefault(x => x.SupportedAuthorityIds.Contains(authority, StringComparer.OrdinalIgnoreCase));
if (provider is null)
{
_context.Trace.WriteLine($"No host provider was found with authority '{authority}'.. falling back to auto-detection.");
_context.Streams.Error.WriteLine($"warning: a supported authority override was set but no such provider supporting authority '{authority}' was found. Falling back to auto-detection.");
}
else
{
return(provider);
}
}
}
//
// Auto-detection
//
_context.Trace.WriteLine("Performing auto-detection of host provider.");
var uri = input.GetRemoteUri();
var probeTimeout = TimeSpan.FromMilliseconds(_context.Settings.AutoDetectProviderTimeout);
_context.Trace.WriteLine($"Auto-detect probe timeout is {probeTimeout.TotalSeconds} ms.");
HttpResponseMessage probeResponse = null;
async Task <IHostProvider> MatchProviderAsync(HostProviderPriority priority)
{
if (_hostProviders.TryGetValue(priority, out ICollection <IHostProvider> providers))
{
_context.Trace.WriteLine($"Checking against {providers.Count} host providers registered with priority '{priority}'.");
// Try matching using the static Git input arguments first (cheap)
if (providers.TryGetFirst(x => x.IsSupported(input), out IHostProvider match))
{
return(match);
}
// Try matching using the HTTP response from a query to the remote URL (expensive).
// The user may have disabled this feature with a zero or negative timeout for performance reasons.
// We only probe the remote once and reuse the same response for all providers.
if (probeTimeout.TotalMilliseconds > 0)
{
if (probeResponse is null)
{
_context.Trace.WriteLine("Querying remote URL for host provider auto-detection.");
using (HttpClient client = _context.HttpClientFactory.CreateClient())
{
client.Timeout = probeTimeout;
try
{
probeResponse = await client.HeadAsync(uri);
}
catch (TaskCanceledException)
{
_context.Streams.Error.WriteLine($"warning: auto-detection of host provider took too long (>{probeTimeout.TotalMilliseconds}ms)");
_context.Streams.Error.WriteLine($"warning: see {Constants.HelpUrls.GcmAutoDetect} for more information.");
}
catch (Exception ex)
{
// The auto detect probing failed for some other reason.
// We don't particular care why, but we should not crash!
_context.Streams.Error.WriteLine($"warning: failed to probe '{uri}' to detect provider");
_context.Streams.Error.WriteLine($"warning: {ex.Message}");
_context.Streams.Error.WriteLine($"warning: see {Constants.HelpUrls.GcmAutoDetect} for more information.");
}
}
}
if (providers.TryGetFirst(x => x.IsSupported(probeResponse), out match))
{
return(match);
}
}
}
return(null);
}
// Match providers starting with the highest priority
return(await MatchProviderAsync(HostProviderPriority.High) ??
await MatchProviderAsync(HostProviderPriority.Normal) ??
await MatchProviderAsync(HostProviderPriority.Low) ??
throw new Exception("No host provider available to service this request."));
}
