/// <summary>
/// Returns an AuthenticationResult object corresponding to the result of authentication done
/// using the client supplied artifacts in the HTTP authorization header in hawk scheme.
/// </summary>
/// <param name="now">Current UNIX time in milliseconds.</param>
/// <param name="request">Request object.</param>
/// <param name="options">Hawk authentication options</param>
/// <returns></returns>
internal static async Task <AuthenticationResult> AuthenticateAsync(ulong now, IRequestMessage request, Options options)
{
ArtifactsContainer artifacts = null;
Credential credential = null;
if (request.HasValidHawkScheme())
{
if (ArtifactsContainer.TryParse(request.Authorization.Parameter, out artifacts))
{
if (artifacts != null && artifacts.AreClientArtifactsValid)
{
credential = options.CredentialsCallback(artifacts.Id);
if (credential != null && credential.IsValid)
{
var normalizedRequest = new NormalizedRequest(request, artifacts, options.HostNameSource);
var crypto = new Cryptographer(normalizedRequest, artifacts, credential);
// Request body is needed only when payload hash is present in the request
string body = null;
if (artifacts.PayloadHash != null && artifacts.PayloadHash.Length > 0)
{
body = await request.ReadBodyAsStringAsync();
}
if (crypto.IsSignatureValid(body, request.ContentType)) // MAC and hash checks
{
if (IsTimestampFresh(now, artifacts, options))
{
// If you get this far, you are authentic. Welcome and thanks for flying Hawk!
return(new AuthenticationResult()
{
IsAuthentic = true,
Artifacts = artifacts,
Credential = credential,
ApplicationSpecificData = artifacts.ApplicationSpecificData
});
}
else
{
// Authentic but for the timestamp freshness.
// Give a chance to the client to correct the clocks skew.
var timestamp = new NormalizedTimestamp(DateTime.UtcNow, credential, options.LocalTimeOffsetMillis);
request.ChallengeParameter = timestamp.ToWwwAuthenticateHeaderParameter();
}
}
}
}
}
}
return(new AuthenticationResult()
{
IsAuthentic = false
});
}
/// <summary>
/// Returns an AuthenticationResult object corresponding to the result of authentication done
/// using the client supplied artifacts in the HTTP authorization header in hawk scheme.
/// </summary>
/// <param name="now">Current UNIX time in milliseconds.</param>
/// <param name="request">Request object.</param>
/// <param name="options">Hawk authentication options</param>
/// <returns></returns>
internal static async Task<AuthenticationResult> AuthenticateAsync(ulong now, IRequestMessage request, Options options)
{
ArtifactsContainer artifacts = null;
Credential credential = null;
if (request.HasValidHawkScheme())
{
if (ArtifactsContainer.TryParse(request.Authorization.Parameter, out artifacts))
{
if (artifacts != null && artifacts.AreClientArtifactsValid)
{
credential = options.CredentialsCallback(artifacts.Id);
if (credential != null && credential.IsValid)
{
var normalizedRequest = new NormalizedRequest(request, artifacts);
var crypto = new Cryptographer(normalizedRequest, artifacts, credential);
// Request body is needed only when payload hash is present in the request
string body = null;
if (artifacts.PayloadHash != null && artifacts.PayloadHash.Length > 0)
{
body = await request.ReadBodyAsStringAsync();
}
if (crypto.IsSignatureValid(body, request.ContentType)) // MAC and hash checks
{
if (IsTimestampFresh(now, artifacts, options))
{
// If you get this far, you are authentic. Welcome and thanks for flying Hawk!
return new AuthenticationResult()
{
IsAuthentic = true,
Artifacts = artifacts,
Credential = credential,
ApplicationSpecificData = artifacts.ApplicationSpecificData
};
}
else
{
// Authentic but for the timestamp freshness.
// Give a chance to the client to correct the clocks skew.
var timestamp = new NormalizedTimestamp(DateTime.UtcNow, credential, options.LocalTimeOffsetMillis);
request.ChallengeParameter = timestamp.ToWwwAuthenticateHeaderParameter();
}
}
}
}
}
}
return new AuthenticationResult() { IsAuthentic = false };
}
/// <summary>
/// Returns true if the server response HMAC cannot be validated, indicating possible tampering.
/// </summary>
private async Task<bool> IsResponseTamperedAsync(ArtifactsContainer artifacts, Cryptographer crypto,
IResponseMessage response)
{
if (response.Headers.ContainsKey(HawkConstants.ServerAuthorizationHeaderName))
{
string header = response.Headers[HawkConstants.ServerAuthorizationHeaderName].FirstOrDefault();
if (!String.IsNullOrWhiteSpace(header) &&
header.Substring(0, HawkConstants.Scheme.Length).ToLower() == HawkConstants.Scheme)
{
ArtifactsContainer serverAuthorizationArtifacts;
if (ArtifactsContainer.TryParse(header.Substring(HawkConstants.Scheme.Length + " ".Length),
out serverAuthorizationArtifacts))
{
// To validate response, ext, hash, and mac in the request artifacts must be
// replaced with the ones from the server.
artifacts.ApplicationSpecificData = serverAuthorizationArtifacts.ApplicationSpecificData;
artifacts.PayloadHash = serverAuthorizationArtifacts.PayloadHash;
artifacts.Mac = serverAuthorizationArtifacts.Mac;
// Response body is needed only if payload hash is present in the server response.
string body = null;
if (artifacts.PayloadHash != null && artifacts.PayloadHash.Length > 0)
{
body = await response.ReadBodyAsStringAsync();
}
bool isValid = crypto.IsSignatureValid(body, response.ContentType);
if (isValid)
{
string appSpecificData = serverAuthorizationArtifacts.ApplicationSpecificData;
isValid = options.VerificationCallback == null ||
options.VerificationCallback(response, appSpecificData);
}
return !isValid;
}
}
}
return true; // Missing header means possible tampered response (to err on the side of caution).
}
/// <summary>
/// Returns an AuthenticationResult object corresponding to the result of authentication done
/// using the client supplied artifacts in the HTTP authorization header in hawk scheme.
/// </summary>
/// <param name="now">Current UNIX time in milliseconds.</param>
/// <param name="request">Request object.</param>
/// <param name="options">Hawk authentication options</param>
/// <returns></returns>
internal static async Task<AuthenticationResult> AuthenticateAsync(ulong now, IRequestMessage request, Options options)
{
ArtifactsContainer artifacts = null;
Credential credential = null;
if (request.HasValidHawkScheme())
{
if (ArtifactsContainer.TryParse(request.Authorization.Parameter, out artifacts))
{
if (artifacts != null && artifacts.AreClientArtifactsValid)
{
string lastUsedBy = options.DetermineNonceReplayCallback(artifacts.Nonce);
if (String.IsNullOrEmpty(lastUsedBy)) // Not an old nonce, and hence not a replay.
{
credential = options.CredentialsCallback(artifacts.Id);
if (credential != null && credential.IsValid)
{
HawkEventSource.Log.Debug(
String.Format("Algorithm={0} Key={1} ID={2}",
credential.Algorithm.ToString(),
Convert.ToBase64String(credential.Key),
credential.Id));
Tuple<string, string> hostAndPort = options.DetermineHostDetailsCallback(request);
var normalizedRequest = new NormalizedRequest(request, artifacts, hostAndPort.Item1, hostAndPort.Item2);
var crypto = new Cryptographer(normalizedRequest, artifacts, credential);
// Request body is needed only when payload hash is present in the request
string body = null;
if (artifacts.PayloadHash != null && artifacts.PayloadHash.Length > 0)
{
body = await request.ReadBodyAsStringAsync();
}
if (crypto.IsSignatureValid(body, request.ContentType)) // MAC and hash checks
{
if (IsTimestampFresh(now, artifacts, options))
{
// If you get this far, you are authentic. Welcome and thanks for flying Hawk!
// Before returning the result, store nonce to detect replays.
options.StoreNonceCallback(artifacts.Nonce, credential.Id, options.ClockSkewSeconds);
return new AuthenticationResult()
{
IsAuthentic = true,
Artifacts = artifacts,
Credential = credential,
ApplicationSpecificData = artifacts.ApplicationSpecificData
};
}
else
{
// Authentic but for the timestamp freshness.
// Give a chance to the client to correct the clocks skew.
var timestamp = new NormalizedTimestamp(DateTime.UtcNow, credential, options.LocalTimeOffsetMillis);
request.ChallengeParameter = timestamp.ToWwwAuthenticateHeaderParameter();
}
}
}
}
else
{
HawkEventSource.Log.NonceReplay(artifacts.Nonce, lastUsedBy);
}
}
}
}
return new AuthenticationResult() { IsAuthentic = false };
}
/// <summary>
/// Returns an AuthenticationResult object corresponding to the result of authentication done
/// using the client supplied artifacts in the bewit query string parameter.
/// </summary>
/// <param name="bewit">Value of the query string parameter with the name of 'bewit'.</param>
/// <param name="now">Date and time in UTC to be used as the base for computing bewit life.</param>
/// <param name="request">Request object.</param>
/// <param name="options">Hawk authentication options</param>
internal static AuthenticationResult Authenticate(string bewit, ulong now, IRequestMessage request, Options options)
{
if (!String.IsNullOrWhiteSpace(bewit))
{
if (request.Method == HttpMethod.Get)
{
if (options != null && options.CredentialsCallback != null)
{
var parts = bewit.ToUtf8StringFromBase64Url().Split('\\');
if (parts.Length == 4)
{
ulong timestamp = 0;
if (UInt64.TryParse(parts[1], out timestamp) && timestamp * 1000 > now)
{
string id = parts[0];
string mac = parts[2];
string ext = parts[3];
if (!String.IsNullOrWhiteSpace(id) && !String.IsNullOrWhiteSpace(mac))
{
RemoveBewitFromUri(request);
Credential credential = options.CredentialsCallback(id);
if (credential != null && credential.IsValid)
{
var artifacts = new ArtifactsContainer()
{
Id = id,
Nonce = String.Empty,
Timestamp = timestamp,
Mac = mac.ToBytesFromBase64(),
ApplicationSpecificData = ext ?? String.Empty
};
var normalizedRequest = new NormalizedRequest(request, artifacts) { IsBewit = true };
var crypto = new Cryptographer(normalizedRequest, artifacts, credential);
if (crypto.IsSignatureValid()) // Bewit is for GET and GET must have no request body
{
return new AuthenticationResult()
{
IsAuthentic = true,
Credential = credential,
Artifacts = artifacts,
ApplicationSpecificData = ext
};
}
}
}
}
}
}
}
}
return new AuthenticationResult() { IsAuthentic = false };
}
/// <summary>
/// Returns an AuthenticationResult object corresponding to the result of authentication done
/// using the client supplied artifacts in the bewit query string parameter.
/// </summary>
/// <param name="bewit">Value of the query string parameter with the name of 'bewit'.</param>
/// <param name="now">Date and time in UTC to be used as the base for computing bewit life.</param>
/// <param name="request">Request object.</param>
/// <param name="options">Hawk authentication options</param>
internal static AuthenticationResult Authenticate(string bewit, ulong now, IRequestMessage request, Options options)
{
if (!String.IsNullOrWhiteSpace(bewit))
{
if (request.Method == HttpMethod.Get)
{
if (options != null && options.CredentialsCallback != null)
{
var parts = bewit.ToUtf8StringFromBase64Url().Split('\\');
if (parts.Length == 4)
{
ulong timestamp = 0;
if (UInt64.TryParse(parts[1], out timestamp) && timestamp * 1000 > now)
{
string id = parts[0];
string mac = parts[2];
string ext = parts[3];
if (!String.IsNullOrWhiteSpace(id) && !String.IsNullOrWhiteSpace(mac))
{
RemoveBewitFromUri(request);
Credential credential = options.CredentialsCallback(id);
if (credential != null && credential.IsValid)
{
var artifacts = new ArtifactsContainer()
{
Id = id,
Nonce = String.Empty,
Timestamp = timestamp,
Mac = mac.ToBytesFromBase64(),
ApplicationSpecificData = ext ?? String.Empty
};
var normalizedRequest = new NormalizedRequest(request, artifacts)
{
IsBewit = true
};
var crypto = new Cryptographer(normalizedRequest, artifacts, credential);
if (crypto.IsSignatureValid()) // Bewit is for GET and GET must have no request body
{
return(new AuthenticationResult()
{
IsAuthentic = true,
Credential = credential,
Artifacts = artifacts,
ApplicationSpecificData = ext
});
}
}
}
}
}
}
}
}
return(new AuthenticationResult()
{
IsAuthentic = false
});
}
/// <summary>
/// Returns an AuthenticationResult object corresponding to the result of authentication done
/// using the client supplied artifacts in the HTTP authorization header in hawk scheme.
/// </summary>
/// <param name="now">Current UNIX time in milliseconds.</param>
/// <param name="request">Request object.</param>
/// <param name="options">Hawk authentication options</param>
/// <returns></returns>
internal static async Task <AuthenticationResult> AuthenticateAsync(ulong now, IRequestMessage request, Options options)
{
ArtifactsContainer artifacts = null;
Credential credential = null;
if (request.HasValidHawkScheme())
{
if (ArtifactsContainer.TryParse(request.Authorization.Parameter, out artifacts))
{
if (artifacts != null && artifacts.AreClientArtifactsValid)
{
string lastUsedBy = options.DetermineNonceReplayCallback(artifacts.Nonce);
if (String.IsNullOrEmpty(lastUsedBy)) // Not an old nonce, and hence not a replay.
{
credential = options.CredentialsCallback(artifacts.Id);
if (credential != null && credential.IsValid)
{
HawkEventSource.Log.Debug(
String.Format("Algorithm={0} Key={1} ID={2}",
credential.Algorithm.ToString(),
Convert.ToBase64String(credential.Key),
credential.Id));
Tuple <string, string> hostAndPort = options.DetermineHostDetailsCallback(request);
var normalizedRequest = new NormalizedRequest(request, artifacts, hostAndPort.Item1, hostAndPort.Item2);
var crypto = new Cryptographer(normalizedRequest, artifacts, credential);
// Request body is needed only when payload hash is present in the request
string body = null;
if (artifacts.PayloadHash != null && artifacts.PayloadHash.Length > 0)
{
body = await request.ReadBodyAsStringAsync();
}
if (crypto.IsSignatureValid(body, request.ContentType)) // MAC and hash checks
{
if (IsTimestampFresh(now, artifacts, options))
{
// If you get this far, you are authentic. Welcome and thanks for flying Hawk!
// Before returning the result, store nonce to detect replays.
options.StoreNonceCallback(artifacts.Nonce, credential.Id, options.ClockSkewSeconds);
return(new AuthenticationResult()
{
IsAuthentic = true,
Artifacts = artifacts,
Credential = credential,
ApplicationSpecificData = artifacts.ApplicationSpecificData
});
}
else
{
// Authentic but for the timestamp freshness.
// Give a chance to the client to correct the clocks skew.
var timestamp = new NormalizedTimestamp(DateTime.UtcNow, credential, options.LocalTimeOffsetMillis);
request.ChallengeParameter = timestamp.ToWwwAuthenticateHeaderParameter();
}
}
}
}
else
{
HawkEventSource.Log.NonceReplay(artifacts.Nonce, lastUsedBy);
}
}
}
}
return(new AuthenticationResult()
{
IsAuthentic = false
});
}
