greenshot/GreenshotPlugin/Core/OAuthHelper.cs

1249 lines
45 KiB
C#

/*
* Greenshot - a free and open source screenshot tool
* Copyright (C) 2007-2016 Thomas Braun, Jens Klingen, Robin Krom
*
* For more information see: http://getgreenshot.org/
* The Greenshot project is hosted on GitHub https://github.com/greenshot/greenshot
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
using GreenshotPlugin.Controls;
using log4net;
using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Diagnostics;
using System.Drawing;
using System.Globalization;
using System.Net;
using System.Net.Sockets;
using System.Security.Cryptography;
using System.Text;
using System.Threading;
namespace GreenshotPlugin.Core {
/// <summary>
/// Provides a predefined set of algorithms that are supported officially by the OAuth 1.x protocol
/// </summary>
public enum OAuthSignatureTypes {
HMACSHA1,
PLAINTEXT,
}
/// <summary>
/// Specify the autorize mode that is used to get the token from the cloud service.
/// </summary>
public enum OAuth2AuthorizeMode {
Unknown, // Will give an exception, caller needs to specify another value
LocalServer, // Will specify a redirect URL to http://localhost:port/authorize, while having a HttpListener
MonitorTitle, // Not implemented yet: Will monitor for title changes
Pin, // Not implemented yet: Will ask the user to enter the shown PIN
EmbeddedBrowser // Will open into an embedded _browser (OAuthLoginForm), and catch the redirect
}
/// <summary>
/// Settings for the OAuth 2 protocol
/// </summary>
public class OAuth2Settings {
public OAuth2Settings() {
AdditionalAttributes = new Dictionary<string, string>();
// Create a default state
State = Guid.NewGuid().ToString();
AuthorizeMode = OAuth2AuthorizeMode.Unknown;
}
public OAuth2AuthorizeMode AuthorizeMode {
get;
set;
}
/// <summary>
/// Specify the name of the cloud service, so it can be used in window titles, logs etc
/// </summary>
public string CloudServiceName {
get;
set;
}
/// <summary>
/// Specify the size of the embedded Browser, if using this
/// </summary>
public Size BrowserSize {
get;
set;
}
/// <summary>
/// The OAuth 2 client id
/// </summary>
public string ClientId {
get;
set;
}
/// <summary>
/// The OAuth 2 client secret
/// </summary>
public string ClientSecret {
get;
set;
}
/// <summary>
/// The OAuth 2 state, this is something that is passed to the server, is not processed but returned back to the client.
/// e.g. a correlation ID
/// Default this is filled with a new Guid
/// </summary>
public string State {
get;
set;
}
/// <summary>
/// The autorization URL where the values of this class can be "injected"
/// </summary>
public string AuthUrlPattern {
get;
set;
}
/// <summary>
/// Get formatted Auth url (this will call a FormatWith(this) on the AuthUrlPattern
/// </summary>
public string FormattedAuthUrl => AuthUrlPattern.FormatWith(this);
/// <summary>
/// The URL to get a Token
/// </summary>
public string TokenUrl {
get;
set;
}
/// <summary>
/// This is the redirect URL, in some implementations this is automatically set (LocalServerCodeReceiver)
/// In some implementations this could be e.g. urn:ietf:wg:oauth:2.0:oob or urn:ietf:wg:oauth:2.0:oob:auto
/// </summary>
public string RedirectUrl {
get;
set;
}
/// <summary>
/// Bearer token for accessing OAuth 2 services
/// </summary>
public string AccessToken {
get;
set;
}
/// <summary>
/// Expire time for the AccessToken, this this time (-60 seconds) is passed a new AccessToken needs to be generated with the RefreshToken
/// </summary>
public DateTimeOffset AccessTokenExpires {
get;
set;
}
/// <summary>
/// Return true if the access token is expired.
/// Important "side-effect": if true is returned the AccessToken will be set to null!
/// </summary>
public bool IsAccessTokenExpired {
get {
bool expired = true;
if (!string.IsNullOrEmpty(AccessToken)) {
expired = DateTimeOffset.Now.AddSeconds(60) > AccessTokenExpires;
}
// Make sure the token is not usable
if (expired) {
AccessToken = null;
}
return expired;
}
}
/// <summary>
/// Token used to get a new Access Token
/// </summary>
public string RefreshToken {
get;
set;
}
/// <summary>
/// Put anything in here which is needed for the OAuth 2 implementation of this specific service but isn't generic, e.g. for Google there is a "scope"
/// </summary>
public IDictionary<string, string> AdditionalAttributes {
get;
set;
}
/// <summary>
/// This contains the code returned from the authorization, but only shortly after it was received.
/// It will be cleared as soon as it was used.
/// </summary>
public string Code {
get;
set;
}
}
/// <summary>
/// An OAuth 1 session object
/// </summary>
public class OAuthSession {
private static readonly ILog Log = LogManager.GetLogger(typeof(OAuthSession));
protected const string OAUTH_VERSION = "1.0";
protected const string OAUTH_PARAMETER_PREFIX = "oauth_";
//
// List of know and used oauth parameters' names
//
protected const string OAUTH_CONSUMER_KEY_KEY = "oauth_consumer_key";
protected const string OAUTH_CALLBACK_KEY = "oauth_callback";
protected const string OAUTH_VERSION_KEY = "oauth_version";
protected const string OAUTH_SIGNATURE_METHOD_KEY = "oauth_signature_method";
protected const string OAUTH_TIMESTAMP_KEY = "oauth_timestamp";
protected const string OAUTH_NONCE_KEY = "oauth_nonce";
protected const string OAUTH_TOKEN_KEY = "oauth_token";
protected const string OAUTH_VERIFIER_KEY = "oauth_verifier";
protected const string OAUTH_TOKEN_SECRET_KEY = "oauth_token_secret";
protected const string OAUTH_SIGNATURE_KEY = "oauth_signature";
protected const string HMACSHA1SignatureType = "HMAC-SHA1";
protected const string PlainTextSignatureType = "PLAINTEXT";
protected static Random random = new Random();
protected const string UnreservedChars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_.~";
private string _userAgent = "Greenshot";
private IDictionary<string, string> _requestTokenResponseParameters;
public IDictionary<string, object> RequestTokenParameters { get; } = new Dictionary<string, object>();
/// <summary>
/// Parameters of the last called getAccessToken
/// </summary>
public IDictionary<string, string> AccessTokenResponseParameters { get; private set; }
/// <summary>
/// Parameters of the last called getRequestToken
/// </summary>
public IDictionary<string, string> RequestTokenResponseParameters => _requestTokenResponseParameters;
private readonly string _consumerKey;
private readonly string _consumerSecret;
// default _browser size
#region PublicProperties
public HTTPMethod RequestTokenMethod {
get;
set;
}
public HTTPMethod AccessTokenMethod {
get;
set;
}
public string RequestTokenUrl {
get;
set;
}
public string AuthorizeUrl {
get;
set;
}
public string AccessTokenUrl {
get;
set;
}
public string Token {
get;
set;
}
public string TokenSecret {
get;
set;
}
public string Verifier {
get;
set;
}
public OAuthSignatureTypes SignatureType {
get;
set;
}
public bool UseMultipartFormData { get; set; }
public string UserAgent {
get {
return _userAgent;
}
set {
_userAgent = value;
}
}
public string CallbackUrl { get; set; } = "http://getgreenshot.org";
public bool CheckVerifier { get; set; } = true;
public Size BrowserSize { get; set; } = new Size(864, 587);
public string LoginTitle { get; set; } = "Authorize Greenshot access";
public bool UseHttpHeadersForAuthorization { get; set; } = true;
public bool AutoLogin {
get;
set;
}
#endregion
/// <summary>
/// Create an OAuthSession with the consumerKey / consumerSecret
/// </summary>
/// <param name="consumerKey">"Public" key for the encoding. When using RSASHA1 this is the path to the private key file</param>
/// <param name="consumerSecret">"Private" key for the encoding. when usin RSASHA1 this is the password for the private key file</param>
public OAuthSession(string consumerKey, string consumerSecret) {
_consumerKey = consumerKey;
_consumerSecret = consumerSecret;
UseMultipartFormData = true;
RequestTokenMethod = HTTPMethod.GET;
AccessTokenMethod = HTTPMethod.GET;
SignatureType = OAuthSignatureTypes.HMACSHA1;
AutoLogin = true;
}
/// <summary>
/// Helper function to compute a hash value
/// </summary>
/// <param name="hashAlgorithm">The hashing algorithm used. If that algorithm needs some initialization, like HMAC and its derivatives, they should be initialized prior to passing it to this function</param>
/// <param name="data">The data to hash</param>
/// <returns>a Base64 string of the hash value</returns>
private static string ComputeHash(HashAlgorithm hashAlgorithm, string data) {
if (hashAlgorithm == null) {
throw new ArgumentNullException(nameof(hashAlgorithm));
}
if (string.IsNullOrEmpty(data)) {
throw new ArgumentNullException(nameof(data));
}
byte[] dataBuffer = Encoding.UTF8.GetBytes(data);
byte[] hashBytes = hashAlgorithm.ComputeHash(dataBuffer);
return Convert.ToBase64String(hashBytes);
}
/// <summary>
/// Generate the normalized paramter string
/// </summary>
/// <param name="queryParameters">the list of query parameters</param>
/// <returns>a string with the normalized query parameters</returns>
private static string GenerateNormalizedParametersString(IDictionary<string, object> queryParameters) {
if (queryParameters == null || queryParameters.Count == 0) {
return string.Empty;
}
queryParameters = new SortedDictionary<string, object>(queryParameters);
StringBuilder sb = new StringBuilder();
foreach (string key in queryParameters.Keys) {
if (queryParameters[key] is string) {
sb.AppendFormat(CultureInfo.InvariantCulture, "{0}={1}&", key, UrlEncode3986($"{queryParameters[key]}"));
}
}
sb.Remove(sb.Length - 1, 1);
return sb.ToString();
}
/// <summary>
/// This is a different Url Encode implementation since the default .NET one outputs the percent encoding in lower case.
/// While this is not a problem with the percent encoding spec, it is used in upper case throughout OAuth
/// The resulting string is for UTF-8 encoding!
/// </summary>
/// <param name="value">The value to Url encode</param>
/// <returns>Returns a Url encoded string (unicode) with UTF-8 encoded % values</returns>
public static string UrlEncode3986(string value) {
StringBuilder result = new StringBuilder();
foreach (char symbol in value) {
if (UnreservedChars.IndexOf(symbol) != -1) {
result.Append(symbol);
} else {
byte[] utf8Bytes = Encoding.UTF8.GetBytes(symbol.ToString());
foreach(byte utf8Byte in utf8Bytes) {
result.AppendFormat("%{0:X2}", utf8Byte);
}
}
}
return result.ToString();
}
/// <summary>
/// Generate the timestamp for the signature
/// </summary>
/// <returns></returns>
public static string GenerateTimeStamp() {
// Default implementation of UNIX time of the current UTC time
TimeSpan ts = DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0);
return Convert.ToInt64(ts.TotalSeconds).ToString();
}
/// <summary>
/// Generate a nonce
/// </summary>
/// <returns></returns>
public static string GenerateNonce() {
// Just a simple implementation of a random number between 123400 and 9999999
return random.Next(123400, 9999999).ToString();
}
/// <summary>
/// Get the request token using the consumer key and secret. Also initializes tokensecret
/// </summary>
/// <returns>response, this doesn't need to be used!!</returns>
private string GetRequestToken() {
IDictionary<string, object> parameters = new Dictionary<string, object>();
foreach(var value in RequestTokenParameters) {
parameters.Add(value);
}
Sign(RequestTokenMethod, RequestTokenUrl, parameters);
string response = MakeRequest(RequestTokenMethod, RequestTokenUrl, null, parameters, null);
if (!string.IsNullOrEmpty(response)) {
response = NetworkHelper.UrlDecode(response);
Log.DebugFormat("Request token response: {0}", response);
_requestTokenResponseParameters = NetworkHelper.ParseQueryString(response);
string value;
if (_requestTokenResponseParameters.TryGetValue(OAUTH_TOKEN_KEY, out value)) {
Token = value;
TokenSecret = _requestTokenResponseParameters[OAUTH_TOKEN_SECRET_KEY];
}
}
return response;
}
/// <summary>
/// Authorize the token by showing the dialog
/// </summary>
/// <param name="requestTokenResponse">Pass the response from the server's request token, so if there is something wrong we can show it.</param>
/// <returns>The request token.</returns>
private string GetAuthorizeToken(string requestTokenResponse) {
if (string.IsNullOrEmpty(Token)) {
Exception e = new Exception("The request token is not set, service responded with: " + requestTokenResponse);
throw e;
}
Log.DebugFormat("Opening AuthorizationLink: {0}", AuthorizationLink);
OAuthLoginForm oAuthLoginForm = new OAuthLoginForm(LoginTitle, BrowserSize, AuthorizationLink, CallbackUrl);
oAuthLoginForm.ShowDialog();
if (oAuthLoginForm.IsOk) {
if (oAuthLoginForm.CallbackParameters != null) {
string tokenValue;
if (oAuthLoginForm.CallbackParameters.TryGetValue(OAUTH_TOKEN_KEY, out tokenValue)) {
Token = tokenValue;
}
string verifierValue;
if (oAuthLoginForm.CallbackParameters.TryGetValue(OAUTH_VERIFIER_KEY, out verifierValue)) {
Verifier = verifierValue;
}
}
}
if (CheckVerifier) {
if (!string.IsNullOrEmpty(Verifier)) {
return Token;
}
return null;
}
return Token;
}
/// <summary>
/// Get the access token
/// </summary>
/// <returns>The access token.</returns>
private string GetAccessToken() {
if (string.IsNullOrEmpty(Token) || (CheckVerifier && string.IsNullOrEmpty(Verifier))) {
Exception e = new Exception("The request token and verifier were not set");
throw e;
}
IDictionary<string, object> parameters = new Dictionary<string, object>();
Sign(AccessTokenMethod, AccessTokenUrl, parameters);
string response = MakeRequest(AccessTokenMethod, AccessTokenUrl, null, parameters, null);
if (!string.IsNullOrEmpty(response)) {
response = NetworkHelper.UrlDecode(response);
Log.DebugFormat("Access token response: {0}", response);
AccessTokenResponseParameters = NetworkHelper.ParseQueryString(response);
string tokenValue;
if (AccessTokenResponseParameters.TryGetValue(OAUTH_TOKEN_KEY, out tokenValue) && tokenValue != null) {
Token = tokenValue;
}
string secretValue;
if (AccessTokenResponseParameters.TryGetValue(OAUTH_TOKEN_SECRET_KEY, out secretValue) && secretValue != null) {
TokenSecret = secretValue;
}
}
return Token;
}
/// <summary>
/// This method goes through the whole authorize process, including a Authorization window.
/// </summary>
/// <returns>true if the process is completed</returns>
public bool Authorize() {
Token = null;
TokenSecret = null;
Verifier = null;
Log.Debug("Creating Token");
string requestTokenResponse;
try {
requestTokenResponse = GetRequestToken();
} catch (Exception ex) {
Log.Error(ex);
throw new NotSupportedException("Service is not available: " + ex.Message);
}
if (string.IsNullOrEmpty(GetAuthorizeToken(requestTokenResponse))) {
Log.Debug("User didn't authenticate!");
return false;
}
try {
Thread.Sleep(1000);
return GetAccessToken() != null;
} catch (Exception ex) {
Log.Error(ex);
throw;
}
}
/// <summary>
/// Get the link to the authorization page for this application.
/// </summary>
/// <returns>The url with a valid request token, or a null string.</returns>
private string AuthorizationLink => AuthorizeUrl + "?" + OAUTH_TOKEN_KEY + "=" + Token + "&" + OAUTH_CALLBACK_KEY + "=" + UrlEncode3986(CallbackUrl);
/// <summary>
/// Submit a web request using oAuth.
/// </summary>
/// <param name="method">GET or POST</param>
/// <param name="requestUrl">The full url, including the querystring for the signing/request</param>
/// <param name="parametersToSign">Parameters for the request, which need to be signed</param>
/// <param name="additionalParameters">Parameters for the request, which do not need to be signed</param>
/// <param name="postData">Data to post (MemoryStream)</param>
/// <returns>The web server response.</returns>
public string MakeOAuthRequest(HTTPMethod method, string requestUrl, IDictionary<string, object> parametersToSign, IDictionary<string, object> additionalParameters, IBinaryContainer postData) {
return MakeOAuthRequest(method, requestUrl, requestUrl, null, parametersToSign, additionalParameters, postData);
}
/// <summary>
/// Submit a web request using oAuth.
/// </summary>
/// <param name="method">GET or POST</param>
/// <param name="requestUrl">The full url, including the querystring for the signing/request</param>
/// <param name="headers">Header values</param>
/// <param name="parametersToSign">Parameters for the request, which need to be signed</param>
/// <param name="additionalParameters">Parameters for the request, which do not need to be signed</param>
/// <param name="postData">Data to post (MemoryStream)</param>
/// <returns>The web server response.</returns>
public string MakeOAuthRequest(HTTPMethod method, string requestUrl, IDictionary<string, string> headers, IDictionary<string, object> parametersToSign, IDictionary<string, object> additionalParameters, IBinaryContainer postData) {
return MakeOAuthRequest(method, requestUrl, requestUrl, headers, parametersToSign, additionalParameters, postData);
}
/// <summary>
/// Submit a web request using oAuth.
/// </summary>
/// <param name="method">GET or POST</param>
/// <param name="signUrl">The full url, including the querystring for the signing</param>
/// <param name="requestUrl">The full url, including the querystring for the request</param>
/// <param name="parametersToSign">Parameters for the request, which need to be signed</param>
/// <param name="additionalParameters">Parameters for the request, which do not need to be signed</param>
/// <param name="postData">Data to post (MemoryStream)</param>
/// <returns>The web server response.</returns>
public string MakeOAuthRequest(HTTPMethod method, string signUrl, string requestUrl, IDictionary<string, object> parametersToSign, IDictionary<string, object> additionalParameters, IBinaryContainer postData) {
return MakeOAuthRequest(method, signUrl, requestUrl, null, parametersToSign, additionalParameters, postData);
}
/// <summary>
/// Submit a web request using oAuth.
/// </summary>
/// <param name="method">GET or POST</param>
/// <param name="signUrl">The full url, including the querystring for the signing</param>
/// <param name="requestUrl">The full url, including the querystring for the request</param>
/// <param name="headers">Headers for the request</param>
/// <param name="parametersToSign">Parameters for the request, which need to be signed</param>
/// <param name="additionalParameters">Parameters for the request, which do not need to be signed</param>
/// <param name="postData">Data to post (MemoryStream)</param>
/// <returns>The web server response.</returns>
public string MakeOAuthRequest(HTTPMethod method, string signUrl, string requestUrl, IDictionary<string, string> headers, IDictionary<string, object> parametersToSign, IDictionary<string, object> additionalParameters, IBinaryContainer postData) {
if (parametersToSign == null) {
parametersToSign = new Dictionary<string, object>();
}
int retries = 2;
Exception lastException = null;
while (retries-- > 0) {
// If we are not trying to get a Authorization or Accestoken, and we don't have a token, create one
if (string.IsNullOrEmpty(Token)) {
if (!AutoLogin || !Authorize()) {
throw new Exception("Not authorized");
}
}
try {
Sign(method, signUrl, parametersToSign);
// Join all parameters
IDictionary<string, object> newParameters = new Dictionary<string, object>();
foreach (var parameter in parametersToSign) {
newParameters.Add(parameter);
}
if (additionalParameters != null) {
foreach (var parameter in additionalParameters) {
newParameters.Add(parameter);
}
}
return MakeRequest(method, requestUrl, headers, newParameters, postData);
} catch (UnauthorizedAccessException uaEx) {
lastException = uaEx;
Token = null;
TokenSecret = null;
// Remove oauth keys, so they aren't added double
List<string> keysToDelete = new List<string>();
foreach (string parameterKey in parametersToSign.Keys)
{
if (parameterKey.StartsWith(OAUTH_PARAMETER_PREFIX))
{
keysToDelete.Add(parameterKey);
}
}
foreach (string keyToDelete in keysToDelete)
{
parametersToSign.Remove(keyToDelete);
}
}
}
if (lastException != null) {
throw lastException;
}
throw new Exception("Not authorized");
}
/// <summary>
/// OAuth sign the parameters, meaning all oauth parameters are added to the supplied dictionary.
/// And additionally a signature is added.
/// </summary>
/// <param name="method">Method (POST,PUT,GET)</param>
/// <param name="requestUrl">Url to call</param>
/// <param name="parameters">IDictionary of string and string</param>
private void Sign(HTTPMethod method, string requestUrl, IDictionary<string, object> parameters) {
if (parameters == null) {
throw new ArgumentNullException(nameof(parameters));
}
// Build the signature base
StringBuilder signatureBase = new StringBuilder();
// Add Method to signature base
signatureBase.Append(method).Append("&");
// Add normalized URL
Uri url = new Uri(requestUrl);
string normalizedUrl = string.Format(CultureInfo.InvariantCulture, "{0}://{1}", url.Scheme, url.Host);
if (!((url.Scheme == "http" && url.Port == 80) || (url.Scheme == "https" && url.Port == 443))) {
normalizedUrl += ":" + url.Port;
}
normalizedUrl += url.AbsolutePath;
signatureBase.Append(UrlEncode3986(normalizedUrl)).Append("&");
// Add normalized parameters
parameters.Add(OAUTH_VERSION_KEY, OAUTH_VERSION);
parameters.Add(OAUTH_NONCE_KEY, GenerateNonce());
parameters.Add(OAUTH_TIMESTAMP_KEY, GenerateTimeStamp());
switch(SignatureType) {
case OAuthSignatureTypes.PLAINTEXT:
parameters.Add(OAUTH_SIGNATURE_METHOD_KEY, PlainTextSignatureType);
break;
default:
parameters.Add(OAUTH_SIGNATURE_METHOD_KEY, HMACSHA1SignatureType);
break;
}
parameters.Add(OAUTH_CONSUMER_KEY_KEY, _consumerKey);
if (CallbackUrl != null && RequestTokenUrl != null && requestUrl.StartsWith(RequestTokenUrl)) {
parameters.Add(OAUTH_CALLBACK_KEY, CallbackUrl);
}
if (!string.IsNullOrEmpty(Verifier)) {
parameters.Add(OAUTH_VERIFIER_KEY, Verifier);
}
if (!string.IsNullOrEmpty(Token)) {
parameters.Add(OAUTH_TOKEN_KEY, Token);
}
signatureBase.Append(UrlEncode3986(GenerateNormalizedParametersString(parameters)));
Log.DebugFormat("Signature base: {0}", signatureBase);
string key = string.Format(CultureInfo.InvariantCulture, "{0}&{1}", UrlEncode3986(_consumerSecret), string.IsNullOrEmpty(TokenSecret) ? string.Empty : UrlEncode3986(TokenSecret));
switch (SignatureType) {
case OAuthSignatureTypes.PLAINTEXT:
parameters.Add(OAUTH_SIGNATURE_KEY, key);
break;
default:
// Generate Signature and add it to the parameters
HMACSHA1 hmacsha1 = new HMACSHA1 {Key = Encoding.UTF8.GetBytes(key)};
string signature = ComputeHash(hmacsha1, signatureBase.ToString());
parameters.Add(OAUTH_SIGNATURE_KEY, signature);
break;
}
}
/// <summary>
/// Make the actual OAuth request, all oauth parameters are passed as header (default) and the others are placed in the url or post data.
/// Any additional parameters added after the Sign call are not in the signature, this could be by design!
/// </summary>
/// <param name="method"></param>
/// <param name="requestUrl"></param>
/// <param name="headers"></param>
/// <param name="parameters"></param>
/// <param name="postData">IBinaryParameter</param>
/// <returns>Response from server</returns>
private string MakeRequest(HTTPMethod method, string requestUrl, IDictionary<string, string> headers, IDictionary<string, object> parameters, IBinaryContainer postData) {
if (parameters == null) {
throw new ArgumentNullException(nameof(parameters));
}
IDictionary<string, object> requestParameters;
// Add oAuth values as HTTP headers, if this is allowed
StringBuilder authHeader = null;
if (UseHttpHeadersForAuthorization) {
authHeader = new StringBuilder();
requestParameters = new Dictionary<string, object>();
foreach (string parameterKey in parameters.Keys) {
if (parameterKey.StartsWith(OAUTH_PARAMETER_PREFIX)) {
authHeader.AppendFormat(CultureInfo.InvariantCulture, "{0}=\"{1}\", ", parameterKey, UrlEncode3986($"{parameters[parameterKey]}"));
} else if (!requestParameters.ContainsKey(parameterKey)) {
requestParameters.Add(parameterKey, parameters[parameterKey]);
}
}
// Remove trailing comma and space and add it to the headers
if (authHeader.Length > 0) {
authHeader.Remove(authHeader.Length - 2, 2);
}
} else {
requestParameters = parameters;
}
if (HTTPMethod.GET == method || postData != null) {
if (requestParameters.Count > 0) {
// Add the parameters to the request
requestUrl += "?" + NetworkHelper.GenerateQueryParameters(requestParameters);
}
}
// Create webrequest
HttpWebRequest webRequest = NetworkHelper.CreateWebRequest(requestUrl, method);
webRequest.ServicePoint.Expect100Continue = false;
webRequest.UserAgent = _userAgent;
if (UseHttpHeadersForAuthorization && authHeader != null) {
Log.DebugFormat("Authorization: OAuth {0}", authHeader);
webRequest.Headers.Add("Authorization: OAuth " + authHeader);
}
if (headers != null) {
foreach(string key in headers.Keys) {
webRequest.Headers.Add(key, headers[key]);
}
}
if ((HTTPMethod.POST == method || HTTPMethod.PUT == method) && postData == null && requestParameters.Count > 0) {
if (UseMultipartFormData) {
NetworkHelper.WriteMultipartFormData(webRequest, requestParameters);
} else {
StringBuilder form = new StringBuilder();
foreach (string parameterKey in requestParameters.Keys)
{
var binaryParameter = parameters[parameterKey] as IBinaryContainer;
form.AppendFormat(CultureInfo.InvariantCulture, "{0}={1}&", UrlEncode3986(parameterKey), binaryParameter != null ? UrlEncode3986(binaryParameter.ToBase64String(Base64FormattingOptions.None)) : UrlEncode3986($"{parameters[parameterKey]}"));
}
// Remove trailing &
if (form.Length > 0) {
form.Remove(form.Length - 1, 1);
}
webRequest.ContentType = "application/x-www-form-urlencoded";
byte[] data = Encoding.UTF8.GetBytes(form.ToString());
using (var requestStream = webRequest.GetRequestStream()) {
requestStream.Write(data, 0, data.Length);
}
}
} else if (postData != null) {
postData.Upload(webRequest);
} else {
webRequest.ContentLength = 0;
}
string responseData;
try {
responseData = NetworkHelper.GetResponseAsString(webRequest);
Log.DebugFormat("Response: {0}", responseData);
} catch (Exception ex) {
Log.Error("Couldn't retrieve response: ", ex);
throw;
}
return responseData;
}
}
/// <summary>
/// OAuth 2.0 verification code receiver that runs a local server on a free port
/// and waits for a call with the authorization verification code.
/// </summary>
public class LocalServerCodeReceiver {
private static readonly ILog Log = LogManager.GetLogger(typeof(LocalServerCodeReceiver));
private readonly ManualResetEvent _ready = new ManualResetEvent(true);
/// <summary>
/// The call back format. Expects one port parameter.
/// Default: http://localhost:{0}/authorize/
/// </summary>
public string LoopbackCallbackUrl { get; set; } = "http://localhost:{0}/authorize/";
/// <summary>
/// HTML code to to return the _browser, default it will try to close the _browser / tab, this won't always work.
/// You can use CloudServiceName where you want to show the CloudServiceName from your OAuth2 settings
/// </summary>
public string ClosePageResponse { get; set; } = @"<html>
<head><title>OAuth 2.0 Authentication CloudServiceName</title></head>
<body>
Greenshot received information from CloudServiceName. You can close this browser / tab if it is not closed itself...
<script type='text/javascript'>
window.setTimeout(function() {
window.open('', '_self', '');
window.close();
}, 1000);
if (window.opener) {
window.opener.checkToken();
}
</script>
</body>
</html>";
private string _redirectUri;
/// <summary>
/// The URL to redirect to
/// </summary>
protected string RedirectUri {
get {
if (!string.IsNullOrEmpty(_redirectUri)) {
return _redirectUri;
}
return _redirectUri = string.Format(LoopbackCallbackUrl, GetRandomUnusedPort());
}
}
private string _cloudServiceName;
private readonly IDictionary<string, string> _returnValues = new Dictionary<string, string>();
/// <summary>
/// The OAuth code receiver
/// </summary>
/// <param name="oauth2Settings"></param>
/// <returns>Dictionary with values</returns>
public IDictionary<string, string> ReceiveCode(OAuth2Settings oauth2Settings) {
// Set the redirect URL on the settings
oauth2Settings.RedirectUrl = RedirectUri;
_cloudServiceName = oauth2Settings.CloudServiceName;
using (var listener = new HttpListener()) {
listener.Prefixes.Add(oauth2Settings.RedirectUrl);
try {
listener.Start();
// Get the formatted FormattedAuthUrl
string authorizationUrl = oauth2Settings.FormattedAuthUrl;
Log.DebugFormat("Open a browser with: {0}", authorizationUrl);
Process.Start(authorizationUrl);
// Wait to get the authorization code response.
var context = listener.BeginGetContext(ListenerCallback, listener);
_ready.Reset();
while (!context.AsyncWaitHandle.WaitOne(1000, true)) {
Log.Debug("Waiting for response");
}
} catch (Exception) {
// Make sure we can clean up, also if the thead is aborted
_ready.Set();
throw;
} finally {
_ready.WaitOne();
listener.Close();
}
}
return _returnValues;
}
/// <summary>
/// Handle a connection async, this allows us to break the waiting
/// </summary>
/// <param name="result">IAsyncResult</param>
private void ListenerCallback(IAsyncResult result) {
HttpListener listener = (HttpListener)result.AsyncState;
//If not listening return immediately as this method is called one last time after Close()
if (!listener.IsListening) {
return;
}
// Use EndGetContext to complete the asynchronous operation.
HttpListenerContext context = listener.EndGetContext(result);
// Handle request
HttpListenerRequest request = context.Request;
try {
NameValueCollection nameValueCollection = request.QueryString;
// Get response object.
using (HttpListenerResponse response = context.Response) {
// Write a "close" response.
byte[] buffer = Encoding.UTF8.GetBytes(ClosePageResponse.Replace("CloudServiceName", _cloudServiceName));
// Write to response stream.
response.ContentLength64 = buffer.Length;
using (var stream = response.OutputStream) {
stream.Write(buffer, 0, buffer.Length);
}
}
// Create a new response URL with a dictionary that contains all the response query parameters.
foreach (var name in nameValueCollection.AllKeys) {
if (!_returnValues.ContainsKey(name)) {
_returnValues.Add(name, nameValueCollection[name]);
}
}
} catch (Exception) {
context.Response.OutputStream.Close();
throw;
}
_ready.Set();
}
/// <summary>
/// Returns a random, unused port.
/// </summary>
/// <returns>port to use</returns>
private static int GetRandomUnusedPort() {
var listener = new TcpListener(IPAddress.Loopback, 0);
try {
listener.Start();
return ((IPEndPoint)listener.LocalEndpoint).Port;
} finally {
listener.Stop();
}
}
}
/// <summary>
/// Code to simplify OAuth 2
/// </summary>
public static class OAuth2Helper {
private const string RefreshToken = "refresh_token";
private const string AccessToken = "access_token";
private const string Code = "code";
private const string ClientId = "client_id";
private const string ClientSecret = "client_secret";
private const string GrantType = "grant_type";
private const string AuthorizationCode = "authorization_code";
private const string RedirectUri = "redirect_uri";
private const string ExpiresIn = "expires_in";
/// <summary>
/// Generate an OAuth 2 Token by using the supplied code
/// </summary>
/// <param name="settings">OAuth2Settings to update with the information that was retrieved</param>
public static void GenerateRefreshToken(OAuth2Settings settings) {
IDictionary<string, object> data = new Dictionary<string, object>();
// Use the returned code to get a refresh code
data.Add(Code, settings.Code);
data.Add(ClientId, settings.ClientId);
data.Add(RedirectUri, settings.RedirectUrl);
data.Add(ClientSecret, settings.ClientSecret);
data.Add(GrantType, AuthorizationCode);
foreach (string key in settings.AdditionalAttributes.Keys) {
data.Add(key, settings.AdditionalAttributes[key]);
}
HttpWebRequest webRequest = NetworkHelper.CreateWebRequest(settings.TokenUrl, HTTPMethod.POST);
NetworkHelper.UploadFormUrlEncoded(webRequest, data);
string accessTokenJsonResult = NetworkHelper.GetResponseAsString(webRequest, true);
IDictionary<string, object> refreshTokenResult = JSONHelper.JsonDecode(accessTokenJsonResult);
if (refreshTokenResult.ContainsKey("error"))
{
if (refreshTokenResult.ContainsKey("error_description")) {
throw new Exception($"{refreshTokenResult["error"]} - {refreshTokenResult["error_description"]}");
}
throw new Exception((string)refreshTokenResult["error"]);
}
// gives as described here: https://developers.google.com/identity/protocols/OAuth2InstalledApp
// "access_token":"1/fFAGRNJru1FTz70BzhT3Zg",
// "expires_in":3920,
// "token_type":"Bearer",
// "refresh_token":"1/xEoDL4iW3cxlI7yDbSRFYNG01kVKM2C-259HOF2aQbI"
if (refreshTokenResult.ContainsKey(AccessToken))
{
settings.AccessToken = (string)refreshTokenResult[AccessToken];
}
if (refreshTokenResult.ContainsKey(RefreshToken))
{
settings.RefreshToken = (string)refreshTokenResult[RefreshToken];
}
if (refreshTokenResult.ContainsKey(ExpiresIn))
{
object seconds = refreshTokenResult[ExpiresIn];
if (seconds != null)
{
settings.AccessTokenExpires = DateTimeOffset.Now.AddSeconds((double)seconds);
}
}
settings.Code = null;
}
/// <summary>
/// Used to update the settings with the callback information
/// </summary>
/// <param name="settings">OAuth2Settings</param>
/// <param name="callbackParameters">IDictionary</param>
/// <returns>true if the access token is already in the callback</returns>
private static bool UpdateFromCallback(OAuth2Settings settings, IDictionary<string, string> callbackParameters)
{
if (!callbackParameters.ContainsKey(AccessToken))
{
return false;
}
if (callbackParameters.ContainsKey(RefreshToken))
{
// Refresh the refresh token :)
settings.RefreshToken = callbackParameters[RefreshToken];
}
if (callbackParameters.ContainsKey(ExpiresIn))
{
var expiresIn = callbackParameters[ExpiresIn];
settings.AccessTokenExpires = DateTimeOffset.MaxValue;
if (expiresIn != null)
{
double seconds;
if (double.TryParse(expiresIn, out seconds))
{
settings.AccessTokenExpires = DateTimeOffset.Now.AddSeconds(seconds);
}
}
}
settings.AccessToken = callbackParameters[AccessToken];
return true;
}
/// <summary>
/// Go out and retrieve a new access token via refresh-token with the TokenUrl in the settings
/// Will upate the access token, refresh token, expire date
/// </summary>
/// <param name="settings"></param>
public static void GenerateAccessToken(OAuth2Settings settings) {
IDictionary<string, object> data = new Dictionary<string, object>();
data.Add(RefreshToken, settings.RefreshToken);
data.Add(ClientId, settings.ClientId);
data.Add(ClientSecret, settings.ClientSecret);
data.Add(GrantType, RefreshToken);
foreach (string key in settings.AdditionalAttributes.Keys) {
data.Add(key, settings.AdditionalAttributes[key]);
}
HttpWebRequest webRequest = NetworkHelper.CreateWebRequest(settings.TokenUrl, HTTPMethod.POST);
NetworkHelper.UploadFormUrlEncoded(webRequest, data);
string accessTokenJsonResult = NetworkHelper.GetResponseAsString(webRequest, true);
// gives as described here: https://developers.google.com/identity/protocols/OAuth2InstalledApp
// "access_token":"1/fFAGRNJru1FTz70BzhT3Zg",
// "expires_in":3920,
// "token_type":"Bearer",
IDictionary<string, object> accessTokenResult = JSONHelper.JsonDecode(accessTokenJsonResult);
if (accessTokenResult.ContainsKey("error")) {
if ("invalid_grant" == (string)accessTokenResult["error"]) {
// Refresh token has also expired, we need a new one!
settings.RefreshToken = null;
settings.AccessToken = null;
settings.AccessTokenExpires = DateTimeOffset.MinValue;
settings.Code = null;
return;
} else {
if (accessTokenResult.ContainsKey("error_description")) {
throw new Exception($"{accessTokenResult["error"]} - {accessTokenResult["error_description"]}");
} else {
throw new Exception((string)accessTokenResult["error"]);
}
}
}
if (accessTokenResult.ContainsKey(AccessToken))
{
settings.AccessToken = (string) accessTokenResult[AccessToken];
settings.AccessTokenExpires = DateTimeOffset.MaxValue;
}
if (accessTokenResult.ContainsKey(RefreshToken)) {
// Refresh the refresh token :)
settings.RefreshToken = (string)accessTokenResult[RefreshToken];
}
if (accessTokenResult.ContainsKey(ExpiresIn))
{
object seconds = accessTokenResult[ExpiresIn];
if (seconds != null)
{
settings.AccessTokenExpires = DateTimeOffset.Now.AddSeconds((double) seconds);
}
}
}
/// <summary>
/// Authenticate by using the mode specified in the settings
/// </summary>
/// <param name="settings">OAuth2Settings</param>
/// <returns>false if it was canceled, true if it worked, exception if not</returns>
public static bool Authenticate(OAuth2Settings settings) {
bool completed;
switch (settings.AuthorizeMode) {
case OAuth2AuthorizeMode.LocalServer:
completed = AuthenticateViaLocalServer(settings);
break;
case OAuth2AuthorizeMode.EmbeddedBrowser:
completed = AuthenticateViaEmbeddedBrowser(settings);
break;
default:
throw new NotImplementedException($"Authorize mode '{settings.AuthorizeMode}' is not 'yet' implemented.");
}
return completed;
}
/// <summary>
/// Authenticate via an embedded browser
/// If this works, return the code
/// </summary>
/// <param name="settings">OAuth2Settings with the Auth / Token url etc</param>
/// <returns>true if completed, false if canceled</returns>
private static bool AuthenticateViaEmbeddedBrowser(OAuth2Settings settings) {
if (string.IsNullOrEmpty(settings.CloudServiceName)) {
throw new ArgumentNullException(nameof(settings.CloudServiceName));
}
if (settings.BrowserSize == Size.Empty) {
throw new ArgumentNullException(nameof(settings.BrowserSize));
}
OAuthLoginForm loginForm = new OAuthLoginForm($"Authorize {settings.CloudServiceName}", settings.BrowserSize, settings.FormattedAuthUrl, settings.RedirectUrl);
loginForm.ShowDialog();
if (loginForm.IsOk) {
string code;
if (loginForm.CallbackParameters.TryGetValue(Code, out code) && !string.IsNullOrEmpty(code)) {
settings.Code = code;
GenerateRefreshToken(settings);
return true;
}
return UpdateFromCallback(settings, loginForm.CallbackParameters);
}
return false;
}
/// <summary>
/// Authenticate via a local server by using the LocalServerCodeReceiver
/// If this works, return the code
/// </summary>
/// <param name="settings">OAuth2Settings with the Auth / Token url etc</param>
/// <returns>true if completed</returns>
private static bool AuthenticateViaLocalServer(OAuth2Settings settings) {
var codeReceiver = new LocalServerCodeReceiver();
IDictionary<string, string> result = codeReceiver.ReceiveCode(settings);
string code;
if (result.TryGetValue(Code, out code) && !string.IsNullOrEmpty(code)) {
settings.Code = code;
GenerateRefreshToken(settings);
return true;
}
string error;
if (result.TryGetValue("error", out error)) {
string errorDescription;
if (result.TryGetValue("error_description", out errorDescription)) {
throw new Exception(errorDescription);
}
if ("access_denied" == error) {
throw new UnauthorizedAccessException("Access denied");
}
throw new Exception(error);
}
return false;
}
/// <summary>
/// Simple helper to add the Authorization Bearer header
/// </summary>
/// <param name="webRequest">WebRequest</param>
/// <param name="settings">OAuth2Settings</param>
public static void AddOAuth2Credentials(HttpWebRequest webRequest, OAuth2Settings settings) {
if (!string.IsNullOrEmpty(settings.AccessToken)) {
webRequest.Headers.Add("Authorization", "Bearer " + settings.AccessToken);
}
}
/// <summary>
/// Check and authenticate or refresh tokens
/// </summary>
/// <param name="settings">OAuth2Settings</param>
public static void CheckAndAuthenticateOrRefresh(OAuth2Settings settings) {
// Get Refresh / Access token
if (string.IsNullOrEmpty(settings.RefreshToken)) {
if (!Authenticate(settings)) {
throw new Exception("Authentication cancelled");
}
}
if (settings.IsAccessTokenExpired) {
GenerateAccessToken(settings);
// Get Refresh / Access token
if (string.IsNullOrEmpty(settings.RefreshToken)) {
if (!Authenticate(settings)) {
throw new Exception("Authentication cancelled");
}
GenerateAccessToken(settings);
}
}
if (settings.IsAccessTokenExpired) {
throw new Exception("Authentication failed");
}
}
/// <summary>
/// CreateWebRequest ready for OAuth 2 access
/// </summary>
/// <param name="method">HTTPMethod</param>
/// <param name="url"></param>
/// <param name="settings">OAuth2Settings</param>
/// <returns>HttpWebRequest</returns>
public static HttpWebRequest CreateOAuth2WebRequest(HTTPMethod method, string url, OAuth2Settings settings) {
CheckAndAuthenticateOrRefresh(settings);
HttpWebRequest webRequest = NetworkHelper.CreateWebRequest(url, method);
AddOAuth2Credentials(webRequest, settings);
return webRequest;
}
}
}