namespace Microshaoft.SharePointApps
{
using Microsoft.IdentityModel;
using Microsoft.IdentityModel.S2S.Protocols.OAuth2;
using Microsoft.IdentityModel.S2S.Tokens;
using Microsoft.SharePoint.Client;
using Microsoft.SharePoint.Client.EventReceivers;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Globalization;
using System.IdentityModel.Selectors;
using System.IdentityModel.Tokens;
using System.IO;
using System.Linq;
using System.Net;
using System.Security.Cryptography.X509Certificates;
using System.Security.Principal;
using System.ServiceModel;
using System.Text;
using System.Web;
using System.Web.Configuration;
using System.Web.Script.Serialization;
using AudienceRestriction = Microsoft.IdentityModel.Tokens.AudienceRestriction;
using AudienceUriValidationFailedException = Microsoft.IdentityModel.Tokens.AudienceUriValidationFailedException;
using SecurityTokenHandlerConfiguration = Microsoft.IdentityModel.Tokens.SecurityTokenHandlerConfiguration;
using X509SigningCredentials = Microsoft.IdentityModel.SecurityTokenService.X509SigningCredentials;
public static class TokenHelper
{
#region public fields
/// <summary>
/// SharePoint principal.
/// </summary>
public const string SharePointPrincipal = "00000003-0000-0ff1-ce00-000000000000";
/// <summary>
/// Lifetime of HighTrust access token, 12 hours.
/// </summary>
public static readonly TimeSpan HighTrustAccessTokenLifetime = TimeSpan.FromHours(12.0);
#endregion public fields
#region public methods
/// <summary>
/// Retrieves the context token string from the specified request by looking for well-known parameter names in the
/// POSTed form parameters and the querystring. Returns null if no context token is found.
/// </summary>
/// <param name="request">HttpRequest in which to look for a context token</param>
/// <returns>The context token string</returns>
public static string GetContextTokenFromRequest(HttpRequest request)
{
return GetContextTokenFromRequest(new HttpRequestWrapper(request));
}
/// <summary>
/// Retrieves the context token string from the specified request by looking for well-known parameter names in the
/// POSTed form parameters and the querystring. Returns null if no context token is found.
/// </summary>
/// <param name="request">HttpRequest in which to look for a context token</param>
/// <returns>The context token string</returns>
public static string GetContextTokenFromRequest(HttpRequestBase request)
{
string[] paramNames = { "AppContext", "AppContextToken", "AccessToken", "SPAppToken" };
foreach (string paramName in paramNames)
{
if (!string.IsNullOrEmpty(request.Form[paramName]))
{
return request.Form[paramName];
}
if (!string.IsNullOrEmpty(request.QueryString[paramName]))
{
return request.QueryString[paramName];
}
}
return null;
}
/// <summary>
/// Validate that a specified context token string is intended for this application based on the parameters
/// specified in web.config. Parameters used from web.config used for validation include ClientId,
/// HostedAppHostNameOverride, HostedAppHostName, ClientSecret, and Realm (if it is specified). If HostedAppHostNameOverride is present,
/// it will be used for validation. Otherwise, if the <paramref name="appHostName"/> is not
/// null, it is used for validation instead of the web.config's HostedAppHostName. If the token is invalid, an
/// exception is thrown. If the token is valid, TokenHelper's static STS metadata url is updated based on the token contents
/// and a JsonWebSecurityToken based on the context token is returned.
/// </summary>
/// <param name="contextTokenString">The context token to validate</param>
/// <param name="appHostName">The URL authority, consisting of Domain Name System (DNS) host name or IP address and the port number, to use for token audience validation.
/// If null, HostedAppHostName web.config setting is used instead. HostedAppHostNameOverride web.config setting, if present, will be used
/// for validation instead of <paramref name="appHostName"/> .</param>
/// <returns>A JsonWebSecurityToken based on the context token.</returns>
public static SharePointContextToken ReadAndValidateContextToken(string contextTokenString, string appHostName = null)
{
JsonWebSecurityTokenHandler tokenHandler = CreateJsonWebSecurityTokenHandler();
SecurityToken securityToken = tokenHandler.ReadToken(contextTokenString);
JsonWebSecurityToken jsonToken = securityToken as JsonWebSecurityToken;
SharePointContextToken token = SharePointContextToken.Create(jsonToken);
string stsAuthority = (new Uri(token.SecurityTokenServiceUri)).Authority;
int firstDot = stsAuthority.IndexOf('.');
GlobalEndPointPrefix = stsAuthority.Substring(0, firstDot);
AcsHostUrl = stsAuthority.Substring(firstDot + 1);
tokenHandler.ValidateToken(jsonToken);
string[] acceptableAudiences;
if (!String.IsNullOrEmpty(HostedAppHostNameOverride))
{
acceptableAudiences = HostedAppHostNameOverride.Split(';');
}
else if (appHostName == null)
{
acceptableAudiences = new[] { HostedAppHostName };
}
else
{
acceptableAudiences = new[] { appHostName };
}
bool validationSuccessful = false;
string realm = Realm ?? token.Realm;
foreach (var audience in acceptableAudiences)
{
string principal = GetFormattedPrincipal(ClientId, audience, realm);
if (StringComparer.OrdinalIgnoreCase.Equals(token.Audience, principal))
{
validationSuccessful = true;
break;
}
}
if (!validationSuccessful)
{
throw new AudienceUriValidationFailedException(
String.Format(CultureInfo.CurrentCulture,
"\"{0}\" is not the intended audience \"{1}\"", String.Join(";", acceptableAudiences), token.Audience));
}
return token;
}
/// <summary>
/// Retrieves an access token from ACS to call the source of the specified context token at the specified
/// targetHost. The targetHost must be registered for the principal that sent the context token.
/// </summary>
/// <param name="contextToken">Context token issued by the intended access token audience</param>
/// <param name="targetHost">Url authority of the target principal</param>
/// <returns>An access token with an audience matching the context token's source</returns>
public static OAuth2AccessTokenResponse GetAccessToken(SharePointContextToken contextToken, string targetHost)
{
string targetPrincipalName = contextToken.TargetPrincipalName;
// Extract the refreshToken from the context token
string refreshToken = contextToken.RefreshToken;
if (String.IsNullOrEmpty(refreshToken))
{
return null;
}
string targetRealm = Realm ?? contextToken.Realm;
return GetAccessToken(refreshToken,
targetPrincipalName,
targetHost,
targetRealm);
}
/// <summary>
/// Uses the specified authorization code to retrieve an access token from ACS to call the specified principal
/// at the specified targetHost. The targetHost must be registered for target principal. If specified realm is
/// null, the "Realm" setting in web.config will be used instead.
/// </summary>
/// <param name="authorizationCode">Authorization code to exchange for access token</param>
/// <param name="targetPrincipalName">Name of the target principal to retrieve an access token for</param>
/// <param name="targetHost">Url authority of the target principal</param>
/// <param name="targetRealm">Realm to use for the access token's nameid and audience</param>
/// <param name="redirectUri">Redirect URI registerd for this app</param>
/// <returns>An access token with an audience of the target principal</returns>
public static OAuth2AccessTokenResponse GetAccessToken(
string authorizationCode,
string targetPrincipalName,
string targetHost,
string targetRealm,
Uri redirectUri)
{
if (targetRealm == null)
{
targetRealm = Realm;
}
string resource = GetFormattedPrincipal(targetPrincipalName, targetHost, targetRealm);
string clientId = GetFormattedPrincipal(ClientId, null, targetRealm);
// Create request for token. The RedirectUri is null here. This will fail if redirect uri is registered
OAuth2AccessTokenRequest oauth2Request =
OAuth2MessageFactory.CreateAccessTokenRequestWithAuthorizationCode(
clientId,
ClientSecret,
authorizationCode,
redirectUri,
resource);
// Get token
OAuth2S2SClient client = new OAuth2S2SClient();
OAuth2AccessTokenResponse oauth2Response;
try
{
oauth2Response =
client.Issue(AcsMetadataParser.GetStsUrl(targetRealm), oauth2Request) as OAuth2AccessTokenResponse;
}
catch (WebException wex)
{
using (StreamReader sr = new StreamReader(wex.Response.GetResponseStream()))
{
string responseText = sr.ReadToEnd();
throw new WebException(wex.Message + " - " + responseText, wex);
}
}
return oauth2Response;
}
/// <summary>
/// Uses the specified refresh token to retrieve an access token from ACS to call the specified principal
/// at the specified targetHost. The targetHost must be registered for target principal. If specified realm is
/// null, the "Realm" setting in web.config will be used instead.
/// </summary>
/// <param name="refreshToken">Refresh token to exchange for access token</param>
/// <param name="targetPrincipalName">Name of the target principal to retrieve an access token for</param>
/// <param name="targetHost">Url authority of the target principal</param>
/// <param name="targetRealm">Realm to use for the access token's nameid and audience</param>
/// <returns>An access token with an audience of the target principal</returns>
public static OAuth2AccessTokenResponse GetAccessToken(
string refreshToken,
string targetPrincipalName,
string targetHost,
string targetRealm)
{
if (targetRealm == null)
{
targetRealm = Realm;
}
string resource = GetFormattedPrincipal(targetPrincipalName, targetHost, targetRealm);
string clientId = GetFormattedPrincipal(ClientId, null, targetRealm);
OAuth2AccessTokenRequest oauth2Request = OAuth2MessageFactory.CreateAccessTokenRequestWithRefreshToken(clientId, ClientSecret, refreshToken, resource);
// Get token
OAuth2S2SClient client = new OAuth2S2SClient();
OAuth2AccessTokenResponse oauth2Response;
try
{
oauth2Response =
client.Issue(AcsMetadataParser.GetStsUrl(targetRealm), oauth2Request) as OAuth2AccessTokenResponse;
}
catch (WebException wex)
{
using (StreamReader sr = new StreamReader(wex.Response.GetResponseStream()))
{
string responseText = sr.ReadToEnd();
throw new WebException(wex.Message + " - " + responseText, wex);
}
}
return oauth2Response;
}
/// <summary>
/// Retrieves an app-only access token from ACS to call the specified principal
/// at the specified targetHost. The targetHost must be registered for target principal. If specified realm is
/// null, the "Realm" setting in web.config will be used instead.
/// </summary>
/// <param name="targetPrincipalName">Name of the target principal to retrieve an access token for</param>
/// <param name="targetHost">Url authority of the target principal</param>
/// <param name="targetRealm">Realm to use for the access token's nameid and audience</param>
/// <returns>An access token with an audience of the target principal</returns>
public static OAuth2AccessTokenResponse GetAppOnlyAccessToken(
string targetPrincipalName,
string targetHost,
string targetRealm)
{
if (targetRealm == null)
{
targetRealm = Realm;
}
string resource = GetFormattedPrincipal(targetPrincipalName, targetHost, targetRealm);
string clientId = GetFormattedPrincipal(ClientId, HostedAppHostName, targetRealm);
OAuth2AccessTokenRequest oauth2Request = OAuth2MessageFactory.CreateAccessTokenRequestWithClientCredentials(clientId, ClientSecret, resource);
oauth2Request.Resource = resource;
// Get token
OAuth2S2SClient client = new OAuth2S2SClient();
OAuth2AccessTokenResponse oauth2Response;
try
{
oauth2Response =
client.Issue(AcsMetadataParser.GetStsUrl(targetRealm), oauth2Request) as OAuth2AccessTokenResponse;
}
catch (WebException wex)
{
using (StreamReader sr = new StreamReader(wex.Response.GetResponseStream()))
{
string responseText = sr.ReadToEnd();
throw new WebException(wex.Message + " - " + responseText, wex);
}
}
return oauth2Response;
}
/// <summary>
/// Creates a client context based on the properties of a remote event receiver
/// </summary>
/// <param name="properties">Properties of a remote event receiver</param>
/// <returns>A ClientContext ready to call the web where the event originated</returns>
public static ClientContext CreateRemoteEventReceiverClientContext(SPRemoteEventProperties properties)
{
Uri sharepointUrl;
if (properties.ListEventProperties != null)
{
sharepointUrl = new Uri(properties.ListEventProperties.WebUrl);
}
else if (properties.ItemEventProperties != null)
{
sharepointUrl = new Uri(properties.ItemEventProperties.WebUrl);
}
else if (properties.WebEventProperties != null)
{
sharepointUrl = new Uri(properties.WebEventProperties.FullUrl);
}
else
{
return null;
}
if (IsHighTrustApp())
{
return GetS2SClientContextWithWindowsIdentity(sharepointUrl, null);
}
return CreateAcsClientContextForUrl(properties, sharepointUrl);
}
/// <summary>
/// Creates a client context based on the properties of an app event
/// </summary>
/// <param name="properties">Properties of an app event</param>
/// <param name="useAppWeb">True to target the app web, false to target the host web</param>
/// <returns>A ClientContext ready to call the app web or the parent web</returns>
public static ClientContext CreateAppEventClientContext(SPRemoteEventProperties properties, bool useAppWeb)
{
if (properties.AppEventProperties == null)
{
return null;
}
Uri sharepointUrl = useAppWeb ? properties.AppEventProperties.AppWebFullUrl : properties.AppEventProperties.HostWebFullUrl;
if (IsHighTrustApp())
{
return GetS2SClientContextWithWindowsIdentity(sharepointUrl, null);
}
return CreateAcsClientContextForUrl(properties, sharepointUrl);
}
/// <summary>
/// Retrieves an access token from ACS using the specified authorization code, and uses that access token to
/// create a client context
/// </summary>
/// <param name="targetUrl">Url of the target SharePoint site</param>
/// <param name="authorizationCode">Authorization code to use when retrieving the access token from ACS</param>
/// <param name="redirectUri">Redirect URI registerd for this app</param>
/// <returns>A ClientContext ready to call targetUrl with a valid access token</returns>
public static ClientContext GetClientContextWithAuthorizationCode(
string targetUrl,
string authorizationCode,
Uri redirectUri)
{
return GetClientContextWithAuthorizationCode(targetUrl, SharePointPrincipal, authorizationCode, GetRealmFromTargetUrl(new Uri(targetUrl)), redirectUri);
}
/// <summary>
/// Retrieves an access token from ACS using the specified authorization code, and uses that access token to
/// create a client context
/// </summary>
/// <param name="targetUrl">Url of the target SharePoint site</param>
/// <param name="targetPrincipalName">Name of the target SharePoint principal</param>
/// <param name="authorizationCode">Authorization code to use when retrieving the access token from ACS</param>
/// <param name="targetRealm">Realm to use for the access token's nameid and audience</param>
/// <param name="redirectUri">Redirect URI registerd for this app</param>
/// <returns>A ClientContext ready to call targetUrl with a valid access token</returns>
public static ClientContext GetClientContextWithAuthorizationCode(
string targetUrl,
string targetPrincipalName,
string authorizationCode,
string targetRealm,
Uri redirectUri)
{
Uri targetUri = new Uri(targetUrl);
string accessToken =
GetAccessToken(authorizationCode, targetPrincipalName, targetUri.Authority, targetRealm, redirectUri).AccessToken;
return GetClientContextWithAccessToken(targetUrl, accessToken);
}
/// <summary>
/// Uses the specified access token to create a client context
/// </summary>
/// <param name="targetUrl">Url of the target SharePoint site</param>
/// <param name="accessToken">Access token to be used when calling the specified targetUrl</param>
/// <returns>A ClientContext ready to call targetUrl with the specified access token</returns>
public static ClientContext GetClientContextWithAccessToken(string targetUrl, string accessToken)
{
ClientContext clientContext = new ClientContext(targetUrl);
clientContext.AuthenticationMode = ClientAuthenticationMode.Anonymous;
clientContext.FormDigestHandlingEnabled = false;
clientContext.ExecutingWebRequest +=
delegate(object oSender, WebRequestEventArgs webRequestEventArgs)
{
webRequestEventArgs.WebRequestExecutor.RequestHeaders["Authorization"] =
"Bearer " + accessToken;
};
return clientContext;
}
/// <summary>
/// Retrieves an access token from ACS using the specified context token, and uses that access token to create
/// a client context
/// </summary>
/// <param name="targetUrl">Url of the target SharePoint site</param>
/// <param name="contextTokenString">Context token received from the target SharePoint site</param>
/// <param name="appHostUrl">Url authority of the hosted app. If this is null, the value in the HostedAppHostName
/// of web.config will be used instead</param>
/// <returns>A ClientContext ready to call targetUrl with a valid access token</returns>
public static ClientContext GetClientContextWithContextToken(
string targetUrl,
string contextTokenString,
string appHostUrl)
{
SharePointContextToken contextToken = ReadAndValidateContextToken(contextTokenString, appHostUrl);
Uri targetUri = new Uri(targetUrl);
string accessToken = GetAccessToken(contextToken, targetUri.Authority).AccessToken;
return GetClientContextWithAccessToken(targetUrl, accessToken);
}
/// <summary>
/// Returns the SharePoint url to which the app should redirect the browser to request consent and get back
/// an authorization code.
/// </summary>
/// <param name="contextUrl">Absolute Url of the SharePoint site</param>
/// <param name="scope">Space-delimited permissions to request from the SharePoint site in "shorthand" format
/// (e.g. "Web.Read Site.Write")</param>
/// <returns>Url of the SharePoint site's OAuth authorization page</returns>
public static string GetAuthorizationUrl(string contextUrl, string scope)
{
return string.Format(
"{0}{1}?IsDlg=1&client_id={2}&scope={3}&response_type=code",
EnsureTrailingSlash(contextUrl),
AuthorizationPage,
ClientId,
scope);
}
/// <summary>
/// Returns the SharePoint url to which the app should redirect the browser to request consent and get back
/// an authorization code.
/// </summary>
/// <param name="contextUrl">Absolute Url of the SharePoint site</param>
/// <param name="scope">Space-delimited permissions to request from the SharePoint site in "shorthand" format
/// (e.g. "Web.Read Site.Write")</param>
/// <param name="redirectUri">Uri to which SharePoint should redirect the browser to after consent is
/// granted</param>
/// <returns>Url of the SharePoint site's OAuth authorization page</returns>
public static string GetAuthorizationUrl(string contextUrl, string scope, string redirectUri)
{
return string.Format(
"{0}{1}?IsDlg=1&client_id={2}&scope={3}&response_type=code&redirect_uri={4}",
EnsureTrailingSlash(contextUrl),
AuthorizationPage,
ClientId,
scope,
redirectUri);
}
/// <summary>
/// Returns the SharePoint url to which the app should redirect the browser to request a new context token.
/// </summary>
/// <param name="contextUrl">Absolute Url of the SharePoint site</param>
/// <param name="redirectUri">Uri to which SharePoint should redirect the browser to with a context token</param>
/// <returns>Url of the SharePoint site's context token redirect page</returns>
public static string GetAppContextTokenRequestUrl(string contextUrl, string redirectUri)
{
return string.Format(
"{0}{1}?client_id={2}&redirect_uri={3}",
EnsureTrailingSlash(contextUrl),
RedirectPage,
ClientId,
redirectUri);
}
/// <summary>
/// Retrieves an S2S access token signed by the application's private certificate on behalf of the specified
/// WindowsIdentity and intended for the SharePoint at the targetApplicationUri. If no Realm is specified in
/// web.config, an auth challenge will be issued to the targetApplicationUri to discover it.
/// </summary>
/// <param name="targetApplicationUri">Url of the target SharePoint site</param>
/// <param name="identity">Windows identity of the user on whose behalf to create the access token</param>
/// <returns>An access token with an audience of the target principal</returns>
public static string GetS2SAccessTokenWithWindowsIdentity(
Uri targetApplicationUri,
WindowsIdentity identity)
{
string realm = string.IsNullOrEmpty(Realm) ? GetRealmFromTargetUrl(targetApplicationUri) : Realm;
JsonWebTokenClaim[] claims = identity != null ? GetClaimsWithWindowsIdentity(identity) : null;
return GetS2SAccessTokenWithClaims(targetApplicationUri.Authority, realm, claims);
}
/// <summary>
/// Retrieves an S2S client context with an access token signed by the application's private certificate on
/// behalf of the specified WindowsIdentity and intended for application at the targetApplicationUri using the
/// targetRealm. If no Realm is specified in web.config, an auth challenge will be issued to the
/// targetApplicationUri to discover it.
/// </summary>
/// <param name="targetApplicationUri">Url of the target SharePoint site</param>
/// <param name="identity">Windows identity of the user on whose behalf to create the access token</param>
/// <returns>A ClientContext using an access token with an audience of the target application</returns>
public static ClientContext GetS2SClientContextWithWindowsIdentity(
Uri targetApplicationUri,
WindowsIdentity identity)
{
string realm = string.IsNullOrEmpty(Realm) ? GetRealmFromTargetUrl(targetApplicationUri) : Realm;
JsonWebTokenClaim[] claims = identity != null ? GetClaimsWithWindowsIdentity(identity) : null;
string accessToken = GetS2SAccessTokenWithClaims(targetApplicationUri.Authority, realm, claims);
return GetClientContextWithAccessToken(targetApplicationUri.ToString(), accessToken);
}
/// <summary>
/// Get authentication realm from SharePoint
/// </summary>
/// <param name="targetApplicationUri">Url of the target SharePoint site</param>
/// <returns>String representation of the realm GUID</returns>
public static string GetRealmFromTargetUrl(Uri targetApplicationUri)
{
WebRequest request = WebRequest.Create(targetApplicationUri + "/_vti_bin/client.svc");
request.Headers.Add("Authorization: Bearer ");
try
{
using (request.GetResponse())
{
}
}
catch (WebException e)
{
if (e.Response == null)
{
return null;
}
string bearerResponseHeader = e.Response.Headers["WWW-Authenticate"];
if (string.IsNullOrEmpty(bearerResponseHeader))
{
return null;
}
const string bearer = "Bearer realm=\"";
int bearerIndex = bearerResponseHeader.IndexOf(bearer, StringComparison.Ordinal);
if (bearerIndex < 0)
{
return null;
}
int realmIndex = bearerIndex + bearer.Length;
if (bearerResponseHeader.Length >= realmIndex + 36)
{
string targetRealm = bearerResponseHeader.Substring(realmIndex, 36);
Guid realmGuid;
if (Guid.TryParse(targetRealm, out realmGuid))
{
return targetRealm;
}
}
}
return null;
}
/// <summary>
/// Determines if this is a high trust app.
/// </summary>
/// <returns>True if this is a high trust app.</returns>
public static bool IsHighTrustApp()
{
return SigningCredentials != null;
}
/// <summary>
/// Ensures that the specified URL ends with '/' if it is not null or empty.
/// </summary>
/// <param name="url">The url.</param>
/// <returns>The url ending with '/' if it is not null or empty.</returns>
public static string EnsureTrailingSlash(string url)
{
if (!string.IsNullOrEmpty(url) && url[url.Length - 1] != '/')
{
return url + "/";
}
return url;
}
#endregion
#region private fields
//
// Configuration Constants
//
private const string AuthorizationPage = "_layouts/15/OAuthAuthorize.aspx";
private const string RedirectPage = "_layouts/15/AppRedirect.aspx";
private const string AcsPrincipalName = "00000001-0000-0000-c000-000000000000";
private const string AcsMetadataEndPointRelativeUrl = "metadata/json/1";
private const string S2SProtocol = "OAuth2";
private const string DelegationIssuance = "DelegationIssuance1.0";
private const string NameIdentifierClaimType = JsonWebTokenConstants.ReservedClaims.NameIdentifier;
private const string TrustedForImpersonationClaimType = "trustedfordelegation";
private const string ActorTokenClaimType = JsonWebTokenConstants.ReservedClaims.ActorToken;
//
// Environment Constants
//
private static string GlobalEndPointPrefix = "accounts";
private static string AcsHostUrl = "accesscontrol.windows.net";
//
// Hosted app configuration
//
private static readonly string ClientId = string.IsNullOrEmpty(WebConfigurationManager.AppSettings.Get("ClientId")) ? WebConfigurationManager.AppSettings.Get("HostedAppName") : WebConfigurationManager.AppSettings.Get("ClientId");
private static readonly string IssuerId = string.IsNullOrEmpty(WebConfigurationManager.AppSettings.Get("IssuerId")) ? ClientId : WebConfigurationManager.AppSettings.Get("IssuerId");
private static readonly string HostedAppHostNameOverride = WebConfigurationManager.AppSettings.Get("HostedAppHostNameOverride");
private static readonly string HostedAppHostName = WebConfigurationManager.AppSettings.Get("HostedAppHostName");
private static readonly string ClientSecret = string.IsNullOrEmpty(WebConfigurationManager.AppSettings.Get("ClientSecret")) ? WebConfigurationManager.AppSettings.Get("HostedAppSigningKey") : WebConfigurationManager.AppSettings.Get("ClientSecret");
private static readonly string SecondaryClientSecret = WebConfigurationManager.AppSettings.Get("SecondaryClientSecret");
private static readonly string Realm = WebConfigurationManager.AppSettings.Get("Realm");
private static readonly string ServiceNamespace = WebConfigurationManager.AppSettings.Get("Realm");
private static readonly string ClientSigningCertificatePath = WebConfigurationManager.AppSettings.Get("ClientSigningCertificatePath");
private static readonly string ClientSigningCertificatePassword = WebConfigurationManager.AppSettings.Get("ClientSigningCertificatePassword");
private static readonly X509Certificate2 ClientCertificate = (string.IsNullOrEmpty(ClientSigningCertificatePath) || string.IsNullOrEmpty(ClientSigningCertificatePassword)) ? null : new X509Certificate2(ClientSigningCertificatePath, ClientSigningCertificatePassword);
private static readonly X509SigningCredentials SigningCredentials = (ClientCertificate == null) ? null : new X509SigningCredentials(ClientCertificate, SecurityAlgorithms.RsaSha256Signature, SecurityAlgorithms.Sha256Digest);
#endregion
#region private methods
private static ClientContext CreateAcsClientContextForUrl(SPRemoteEventProperties properties, Uri sharepointUrl)
{
string contextTokenString = properties.ContextToken;
if (String.IsNullOrEmpty(contextTokenString))
{
return null;
}
SharePointContextToken contextToken = ReadAndValidateContextToken(contextTokenString, OperationContext.Current.IncomingMessageHeaders.To.Host);
string accessToken = GetAccessToken(contextToken, sharepointUrl.Authority).AccessToken;
return GetClientContextWithAccessToken(sharepointUrl.ToString(), accessToken);
}
private static string GetAcsMetadataEndpointUrl()
{
return Path.Combine(GetAcsGlobalEndpointUrl(), AcsMetadataEndPointRelativeUrl);
}
private static string GetFormattedPrincipal(string principalName, string hostName, string realm)
{
if (!String.IsNullOrEmpty(hostName))
{
return String.Format(CultureInfo.InvariantCulture, "{0}/{1}@{2}", principalName, hostName, realm);
}
return String.Format(CultureInfo.InvariantCulture, "{0}@{1}", principalName, realm);
}
private static string GetAcsPrincipalName(string realm)
{
return GetFormattedPrincipal(AcsPrincipalName, new Uri(GetAcsGlobalEndpointUrl()).Host, realm);
}
private static string GetAcsGlobalEndpointUrl()
{
return String.Format(CultureInfo.InvariantCulture, "https://{0}.{1}/", GlobalEndPointPrefix, AcsHostUrl);
}
private static JsonWebSecurityTokenHandler CreateJsonWebSecurityTokenHandler()
{
JsonWebSecurityTokenHandler handler = new JsonWebSecurityTokenHandler();
handler.Configuration = new SecurityTokenHandlerConfiguration();
handler.Configuration.AudienceRestriction = new AudienceRestriction(AudienceUriMode.Never);
handler.Configuration.CertificateValidator = X509CertificateValidator.None;
List<byte[]> securityKeys = new List<byte[]>();
securityKeys.Add(Convert.FromBase64String(ClientSecret));
if (!string.IsNullOrEmpty(SecondaryClientSecret))
{
securityKeys.Add(Convert.FromBase64String(SecondaryClientSecret));
}
List<SecurityToken> securityTokens = new List<SecurityToken>();
securityTokens.Add(new MultipleSymmetricKeySecurityToken(securityKeys));
handler.Configuration.IssuerTokenResolver =
SecurityTokenResolver.CreateDefaultSecurityTokenResolver(
new ReadOnlyCollection<SecurityToken>(securityTokens),
false);
SymmetricKeyIssuerNameRegistry issuerNameRegistry = new SymmetricKeyIssuerNameRegistry();
foreach (byte[] securitykey in securityKeys)
{
issuerNameRegistry.AddTrustedIssuer(securitykey, GetAcsPrincipalName(ServiceNamespace));
}
handler.Configuration.IssuerNameRegistry = issuerNameRegistry;
return handler;
}
private static string GetS2SAccessTokenWithClaims(
string targetApplicationHostName,
string targetRealm,
IEnumerable<JsonWebTokenClaim> claims)
{
return IssueToken(
ClientId,
IssuerId,
targetRealm,
SharePointPrincipal,
targetRealm,
targetApplicationHostName,
true,
claims,
claims == null);
}
private static JsonWebTokenClaim[] GetClaimsWithWindowsIdentity(WindowsIdentity identity)
{
JsonWebTokenClaim[] claims = new JsonWebTokenClaim[]
{
new JsonWebTokenClaim(NameIdentifierClaimType, identity.User.Value.ToLower()),
new JsonWebTokenClaim("nii", "urn:office:idp:activedirectory")
};
return claims;
}
private static string IssueToken(
string sourceApplication,
string issuerApplication,
string sourceRealm,
string targetApplication,
string targetRealm,
string targetApplicationHostName,
bool trustedForDelegation,
IEnumerable<JsonWebTokenClaim> claims,
bool appOnly = false)
{
if (null == SigningCredentials)
{
throw new InvalidOperationException("SigningCredentials was not initialized");
}
#region Actor token
string issuer = string.IsNullOrEmpty(sourceRealm) ? issuerApplication : string.Format("{0}@{1}", issuerApplication, sourceRealm);
string nameid = string.IsNullOrEmpty(sourceRealm) ? sourceApplication : string.Format("{0}@{1}", sourceApplication, sourceRealm);
string audience = string.Format("{0}/{1}@{2}", targetApplication, targetApplicationHostName, targetRealm);
List<JsonWebTokenClaim> actorClaims = new List<JsonWebTokenClaim>();
actorClaims.Add(new JsonWebTokenClaim(JsonWebTokenConstants.ReservedClaims.NameIdentifier, nameid));
if (trustedForDelegation && !appOnly)
{
actorClaims.Add(new JsonWebTokenClaim(TrustedForImpersonationClaimType, "true"));
}
// Create token
JsonWebSecurityToken actorToken = new JsonWebSecurityToken(
issuer: issuer,
audience: audience,
validFrom: DateTime.UtcNow,
validTo: DateTime.UtcNow.Add(HighTrustAccessTokenLifetime),
signingCredentials: SigningCredentials,
claims: actorClaims);
string actorTokenString = new JsonWebSecurityTokenHandler().WriteTokenAsString(actorToken);
if (appOnly)
{
// App-only token is the same as actor token for delegated case
return actorTokenString;
}
#endregion Actor token
#region Outer token
List<JsonWebTokenClaim> outerClaims = null == claims ? new List<JsonWebTokenClaim>() : new List<JsonWebTokenClaim>(claims);
outerClaims.Add(new JsonWebTokenClaim(ActorTokenClaimType, actorTokenString));
JsonWebSecurityToken jsonToken = new JsonWebSecurityToken(
nameid, // outer token issuer should match actor token nameid
audience,
DateTime.UtcNow,
DateTime.UtcNow.Add(HighTrustAccessTokenLifetime),
outerClaims);
string accessToken = new JsonWebSecurityTokenHandler().WriteTokenAsString(jsonToken);
#endregion Outer token
return accessToken;
}
#endregion
#region AcsMetadataParser
// This class is used to get MetaData document from the global STS endpoint. It contains
// methods to parse the MetaData document and get endpoints and STS certificate.
public static class AcsMetadataParser
{
public static X509Certificate2 GetAcsSigningCert(string realm)
{
JsonMetadataDocument document = GetMetadataDocument(realm);
if (null != document.keys && document.keys.Count > 0)
{
JsonKey signingKey = document.keys[0];
if (null != signingKey && null != signingKey.keyValue)
{
return new X509Certificate2(Encoding.UTF8.GetBytes(signingKey.keyValue.value));
}
}
throw new Exception("Metadata document does not contain ACS signing certificate.");
}
public static string GetDelegationServiceUrl(string realm)
{
JsonMetadataDocument document = GetMetadataDocument(realm);
JsonEndpoint delegationEndpoint = document.endpoints.SingleOrDefault(e => e.protocol == DelegationIssuance);
if (null != delegationEndpoint)
{
return delegationEndpoint.location;
}
throw new Exception("Metadata document does not contain Delegation Service endpoint Url");
}
private static JsonMetadataDocument GetMetadataDocument(string realm)
{
string acsMetadataEndpointUrlWithRealm = String.Format(CultureInfo.InvariantCulture, "{0}?realm={1}",
GetAcsMetadataEndpointUrl(),
realm);
byte[] acsMetadata;
using (WebClient webClient = new WebClient())
{
acsMetadata = webClient.DownloadData(acsMetadataEndpointUrlWithRealm);
}
string jsonResponseString = Encoding.UTF8.GetString(acsMetadata);
JavaScriptSerializer serializer = new JavaScriptSerializer();
JsonMetadataDocument document = serializer.Deserialize<JsonMetadataDocument>(jsonResponseString);
if (null == document)
{
throw new Exception("No metadata document found at the global endpoint " + acsMetadataEndpointUrlWithRealm);
}
return document;
}
public static string GetStsUrl(string realm)
{
JsonMetadataDocument document = GetMetadataDocument(realm);
JsonEndpoint s2sEndpoint = document.endpoints.SingleOrDefault(e => e.protocol == S2SProtocol);
if (null != s2sEndpoint)
{
return s2sEndpoint.location;
}
throw new Exception("Metadata document does not contain STS endpoint url");
}
private class JsonMetadataDocument
{
public string serviceName { get; set; }
public List<JsonEndpoint> endpoints { get; set; }
public List<JsonKey> keys { get; set; }
}
private class JsonEndpoint
{
public string location { get; set; }
public string protocol { get; set; }
public string usage { get; set; }
}
private class JsonKeyValue
{
public string type { get; set; }
public string value { get; set; }
}
private class JsonKey
{
public string usage { get; set; }
public JsonKeyValue keyValue { get; set; }
}
}
#endregion
}
/// <summary>
/// A JsonWebSecurityToken generated by SharePoint to authenticate to a 3rd party application and allow callbacks using a refresh token
/// </summary>
public class SharePointContextToken : JsonWebSecurityToken
{
public static SharePointContextToken Create(JsonWebSecurityToken contextToken)
{
return new SharePointContextToken(contextToken.Issuer, contextToken.Audience, contextToken.ValidFrom, contextToken.ValidTo, contextToken.Claims);
}
public SharePointContextToken(string issuer, string audience, DateTime validFrom, DateTime validTo, IEnumerable<JsonWebTokenClaim> claims)
: base(issuer, audience, validFrom, validTo, claims)
{
}
public SharePointContextToken(string issuer, string audience, DateTime validFrom, DateTime validTo, IEnumerable<JsonWebTokenClaim> claims, SecurityToken issuerToken, JsonWebSecurityToken actorToken)
: base(issuer, audience, validFrom, validTo, claims, issuerToken, actorToken)
{
}
public SharePointContextToken(string issuer, string audience, DateTime validFrom, DateTime validTo, IEnumerable<JsonWebTokenClaim> claims, SigningCredentials signingCredentials)
: base(issuer, audience, validFrom, validTo, claims, signingCredentials)
{
}
public string NameId
{
get
{
return GetClaimValue(this, "nameid");
}
}
/// <summary>
/// The principal name portion of the context token's "appctxsender" claim
/// </summary>
public string TargetPrincipalName
{
get
{
string appctxsender = GetClaimValue(this, "appctxsender");
if (appctxsender == null)
{
return null;
}
return appctxsender.Split('@')[0];
}
}
/// <summary>
/// The context token's "refreshtoken" claim
/// </summary>
public string RefreshToken
{
get
{
return GetClaimValue(this, "refreshtoken");
}
}
/// <summary>
/// The context token's "CacheKey" claim
/// </summary>
public string CacheKey
{
get
{
string appctx = GetClaimValue(this, "appctx");
if (appctx == null)
{
return null;
}
ClientContext ctx = new ClientContext("http://tempuri.org");
Dictionary<string, object> dict = (Dictionary<string, object>)ctx.ParseObjectFromJsonString(appctx);
string cacheKey = (string)dict["CacheKey"];
return cacheKey;
}
}
/// <summary>
/// The context token's "SecurityTokenServiceUri" claim
/// </summary>
public string SecurityTokenServiceUri
{
get
{
string appctx = GetClaimValue(this, "appctx");
if (appctx == null)
{
return null;
}
ClientContext ctx = new ClientContext("http://tempuri.org");
Dictionary<string, object> dict = (Dictionary<string, object>)ctx.ParseObjectFromJsonString(appctx);
string securityTokenServiceUri = (string)dict["SecurityTokenServiceUri"];
return securityTokenServiceUri;
}
}
/// <summary>
/// The realm portion of the context token's "audience" claim
/// </summary>
public string Realm
{
get
{
string aud = Audience;
if (aud == null)
{
return null;
}
string tokenRealm = aud.Substring(aud.IndexOf('@') + 1);
return tokenRealm;
}
}
private static string GetClaimValue(JsonWebSecurityToken token, string claimType)
{
if (token == null)
{
throw new ArgumentNullException("token");
}
foreach (JsonWebTokenClaim claim in token.Claims)
{
if (StringComparer.Ordinal.Equals(claim.ClaimType, claimType))
{
return claim.Value;
}
}
return null;
}
}
/// <summary>
/// Represents a security token which contains multiple security keys that are generated using symmetric algorithms.
/// </summary>
public class MultipleSymmetricKeySecurityToken : SecurityToken
{
/// <summary>
/// Initializes a new instance of the MultipleSymmetricKeySecurityToken class.
/// </summary>
/// <param name="keys">An enumeration of Byte arrays that contain the symmetric keys.</param>
public MultipleSymmetricKeySecurityToken(IEnumerable<byte[]> keys)
: this(UniqueId.CreateUniqueId(), keys)
{
}
/// <summary>
/// Initializes a new instance of the MultipleSymmetricKeySecurityToken class.
/// </summary>
/// <param name="tokenId">The unique identifier of the security token.</param>
/// <param name="keys">An enumeration of Byte arrays that contain the symmetric keys.</param>
public MultipleSymmetricKeySecurityToken(string tokenId, IEnumerable<byte[]> keys)
{
if (keys == null)
{
throw new ArgumentNullException("keys");
}
if (String.IsNullOrEmpty(tokenId))
{
throw new ArgumentException("Value cannot be a null or empty string.", "tokenId");
}
foreach (byte[] key in keys)
{
if (key.Length <= 0)
{
throw new ArgumentException("The key length must be greater then zero.", "keys");
}
}
id = tokenId;
effectiveTime = DateTime.UtcNow;
securityKeys = CreateSymmetricSecurityKeys(keys);
}
/// <summary>
/// Gets the unique identifier of the security token.
/// </summary>
public override string Id
{
get
{
return id;
}
}
/// <summary>
/// Gets the cryptographic keys associated with the security token.
/// </summary>
public override ReadOnlyCollection<SecurityKey> SecurityKeys
{
get
{
return securityKeys.AsReadOnly();
}
}
/// <summary>
/// Gets the first instant in time at which this security token is valid.
/// </summary>
public override DateTime ValidFrom
{
get
{
return effectiveTime;
}
}
/// <summary>
/// Gets the last instant in time at which this security token is valid.
/// </summary>
public override DateTime ValidTo
{
get
{
// Never expire
return DateTime.MaxValue;
}
}
/// <summary>
/// Returns a value that indicates whether the key identifier for this instance can be resolved to the specified key identifier.
/// </summary>
/// <param name="keyIdentifierClause">A SecurityKeyIdentifierClause to compare to this instance</param>
/// <returns>true if keyIdentifierClause is a SecurityKeyIdentifierClause and it has the same unique identifier as the Id property; otherwise, false.</returns>
public override bool MatchesKeyIdentifierClause(SecurityKeyIdentifierClause keyIdentifierClause)
{
if (keyIdentifierClause == null)
{
throw new ArgumentNullException("keyIdentifierClause");
}
// Since this is a symmetric token and we do not have IDs to distinguish tokens, we just check for the
// presence of a SymmetricIssuerKeyIdentifier. The actual mapping to the issuer takes place later
// when the key is matched to the issuer.
if (keyIdentifierClause is SymmetricIssuerKeyIdentifierClause)
{
return true;
}
return base.MatchesKeyIdentifierClause(keyIdentifierClause);
}
#region private members
private List<SecurityKey> CreateSymmetricSecurityKeys(IEnumerable<byte[]> keys)
{
List<SecurityKey> symmetricKeys = new List<SecurityKey>();
foreach (byte[] key in keys)
{
symmetricKeys.Add(new InMemorySymmetricSecurityKey(key));
}
return symmetricKeys;
}
private string id;
private DateTime effectiveTime;
private List<SecurityKey> securityKeys;
#endregion
}
}
namespace Microshaoft.SharePointApps
{
using Microsoft.IdentityModel.S2S.Protocols.OAuth2;
using Microsoft.IdentityModel.Tokens;
using Microsoft.SharePoint.Client;
using System;
using System.Net;
using System.Security.Principal;
using System.Web;
using System.Web.Configuration;
/// <summary>
/// Encapsulates all the information from SharePoint.
/// </summary>
public abstract class SharePointContext
{
public const string SPHostUrlKey = "SPHostUrl";
public const string SPAppWebUrlKey = "SPAppWebUrl";
public const string SPLanguageKey = "SPLanguage";
public const string SPClientTagKey = "SPClientTag";
public const string SPProductNumberKey = "SPProductNumber";
protected static readonly TimeSpan AccessTokenLifetimeTolerance = TimeSpan.FromMinutes(5.0);
private readonly Uri spHostUrl;
private readonly Uri spAppWebUrl;
private readonly string spLanguage;
private readonly string spClientTag;
private readonly string spProductNumber;
// <AccessTokenString, UtcExpiresOn>
protected Tuple<string, DateTime> userAccessTokenForSPHost;
protected Tuple<string, DateTime> userAccessTokenForSPAppWeb;
protected Tuple<string, DateTime> appOnlyAccessTokenForSPHost;
protected Tuple<string, DateTime> appOnlyAccessTokenForSPAppWeb;
/// <summary>
/// Gets the SharePoint host url from QueryString of the specified HTTP request.
/// </summary>
/// <param name="httpRequest">The specified HTTP request.</param>
/// <returns>The SharePoint host url. Returns <c>null</c> if the HTTP request doesn't contain the SharePoint host url.</returns>
public static Uri GetSPHostUrl(HttpRequestBase httpRequest)
{
if (httpRequest == null)
{
throw new ArgumentNullException("httpRequest");
}
string spHostUrlString = TokenHelper.EnsureTrailingSlash(httpRequest.QueryString[SPHostUrlKey]);
Uri spHostUrl;
if (Uri.TryCreate(spHostUrlString, UriKind.Absolute, out spHostUrl) &&
(spHostUrl.Scheme == Uri.UriSchemeHttp || spHostUrl.Scheme == Uri.UriSchemeHttps))
{
return spHostUrl;
}
return null;
}
/// <summary>
/// Gets the SharePoint host url from QueryString of the specified HTTP request.
/// </summary>
/// <param name="httpRequest">The specified HTTP request.</param>
/// <returns>The SharePoint host url. Returns <c>null</c> if the HTTP request doesn't contain the SharePoint host url.</returns>
public static Uri GetSPHostUrl(HttpRequest httpRequest)
{
return GetSPHostUrl(new HttpRequestWrapper(httpRequest));
}
/// <summary>
/// The SharePoint host url.
/// </summary>
public Uri SPHostUrl
{
get { return this.spHostUrl; }
}
/// <summary>
/// The SharePoint app web url.
/// </summary>
public Uri SPAppWebUrl
{
get { return this.spAppWebUrl; }
}
/// <summary>
/// The SharePoint language.
/// </summary>
public string SPLanguage
{
get { return this.spLanguage; }
}
/// <summary>
/// The SharePoint client tag.
/// </summary>
public string SPClientTag
{
get { return this.spClientTag; }
}
/// <summary>
/// The SharePoint product number.
/// </summary>
public string SPProductNumber
{
get { return this.spProductNumber; }
}
/// <summary>
/// The user access token for the SharePoint host.
/// </summary>
public abstract string UserAccessTokenForSPHost
{
get;
}
/// <summary>
/// The user access token for the SharePoint app web.
/// </summary>
public abstract string UserAccessTokenForSPAppWeb
{
get;
}
/// <summary>
/// The app only access token for the SharePoint host.
/// </summary>
public abstract string AppOnlyAccessTokenForSPHost
{
get;
}
/// <summary>
/// The app only access token for the SharePoint app web.
/// </summary>
public abstract string AppOnlyAccessTokenForSPAppWeb
{
get;
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="spHostUrl">The SharePoint host url.</param>
/// <param name="spAppWebUrl">The SharePoint app web url.</param>
/// <param name="spLanguage">The SharePoint language.</param>
/// <param name="spClientTag">The SharePoint client tag.</param>
/// <param name="spProductNumber">The SharePoint product number.</param>
protected SharePointContext(Uri spHostUrl, Uri spAppWebUrl, string spLanguage, string spClientTag, string spProductNumber)
{
if (spHostUrl == null)
{
throw new ArgumentNullException("spHostUrl");
}
if (string.IsNullOrEmpty(spLanguage))
{
throw new ArgumentNullException("spLanguage");
}
if (string.IsNullOrEmpty(spClientTag))
{
throw new ArgumentNullException("spClientTag");
}
if (string.IsNullOrEmpty(spProductNumber))
{
throw new ArgumentNullException("spProductNumber");
}
this.spHostUrl = spHostUrl;
this.spAppWebUrl = spAppWebUrl;
this.spLanguage = spLanguage;
this.spClientTag = spClientTag;
this.spProductNumber = spProductNumber;
}
/// <summary>
/// Creates a user ClientContext for the SharePoint host.
/// </summary>
/// <returns>A ClientContext instance.</returns>
public ClientContext CreateUserClientContextForSPHost()
{
return CreateClientContext(this.SPHostUrl, this.UserAccessTokenForSPHost);
}
/// <summary>
/// Creates a user ClientContext for the SharePoint app web.
/// </summary>
/// <returns>A ClientContext instance.</returns>
public ClientContext CreateUserClientContextForSPAppWeb()
{
return CreateClientContext(this.SPAppWebUrl, this.UserAccessTokenForSPAppWeb);
}
/// <summary>
/// Creates app only ClientContext for the SharePoint host.
/// </summary>
/// <returns>A ClientContext instance.</returns>
public ClientContext CreateAppOnlyClientContextForSPHost()
{
return CreateClientContext(this.SPHostUrl, this.AppOnlyAccessTokenForSPHost);
}
/// <summary>
/// Creates an app only ClientContext for the SharePoint app web.
/// </summary>
/// <returns>A ClientContext instance.</returns>
public ClientContext CreateAppOnlyClientContextForSPAppWeb()
{
return CreateClientContext(this.SPAppWebUrl, this.AppOnlyAccessTokenForSPAppWeb);
}
/// <summary>
/// Gets the database connection string from SharePoint for autohosted app.
/// </summary>
/// <returns>The database connection string. Returns <c>null</c> if the app is not autohosted or there is no database.</returns>
public string GetDatabaseConnectionString()
{
string dbConnectionString = null;
using (ClientContext clientContext = CreateAppOnlyClientContextForSPHost())
{
if (clientContext != null)
{
var result = AppInstance.RetrieveAppDatabaseConnectionString(clientContext);
clientContext.ExecuteQuery();
dbConnectionString = result.Value;
}
}
if (dbConnectionString == null)
{
const string LocalDBInstanceForDebuggingKey = "LocalDBInstanceForDebugging";
var dbConnectionStringSettings = WebConfigurationManager.ConnectionStrings[LocalDBInstanceForDebuggingKey];
dbConnectionString = dbConnectionStringSettings != null ? dbConnectionStringSettings.ConnectionString : null;
}
return dbConnectionString;
}
/// <summary>
/// Determines if the specified access token is valid.
/// It considers an access token as not valid if it is null, or it has expired.
/// </summary>
/// <param name="accessToken">The access token to verify.</param>
/// <returns>True if the access token is valid.</returns>
protected static bool IsAccessTokenValid(Tuple<string, DateTime> accessToken)
{
return accessToken != null &&
!string.IsNullOrEmpty(accessToken.Item1) &&
accessToken.Item2 > DateTime.UtcNow;
}
/// <summary>
/// Creates a ClientContext with the specified SharePoint site url and the access token.
/// </summary>
/// <param name="spSiteUrl">The site url.</param>
/// <param name="accessToken">The access token.</param>
/// <returns>A ClientContext instance.</returns>
private static ClientContext CreateClientContext(Uri spSiteUrl, string accessToken)
{
if (spSiteUrl != null && !string.IsNullOrEmpty(accessToken))
{
return TokenHelper.GetClientContextWithAccessToken(spSiteUrl.AbsoluteUri, accessToken);
}
return null;
}
}
/// <summary>
/// Redirection status.
/// </summary>
public enum RedirectionStatus
{
Ok,
ShouldRedirect,
CanNotRedirect
}
/// <summary>
/// Provides SharePointContext instances.
/// </summary>
public abstract class SharePointContextProvider
{
private static SharePointContextProvider current;
/// <summary>
/// The current SharePointContextProvider instance.
/// </summary>
public static SharePointContextProvider Current
{
get { return SharePointContextProvider.current; }
}
/// <summary>
/// Initializes the default SharePointContextProvider instance.
/// </summary>
static SharePointContextProvider()
{
if (!TokenHelper.IsHighTrustApp())
{
SharePointContextProvider.current = new SharePointAcsContextProvider();
}
else
{
SharePointContextProvider.current = new SharePointHighTrustContextProvider();
}
}
/// <summary>
/// Registers the specified SharePointContextProvider instance as current.
/// It should be called by Application_Start() in Global.asax.
/// </summary>
/// <param name="provider">The SharePointContextProvider to be set as current.</param>
public static void Register(SharePointContextProvider provider)
{
if (provider == null)
{
throw new ArgumentNullException("provider");
}
SharePointContextProvider.current = provider;
}
/// <summary>
/// Checks if it is necessary to redirect to SharePoint for user to authenticate.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <param name="redirectUrl">The redirect url to SharePoint if the status is ShouldRedirect. <c>Null</c> if the status is Ok or CanNotRedirect.</param>
/// <returns>Redirection status.</returns>
public static RedirectionStatus CheckRedirectionStatus(HttpContextBase httpContext, out Uri redirectUrl)
{
if (httpContext == null)
{
throw new ArgumentNullException("httpContext");
}
redirectUrl = null;
if (SharePointContextProvider.Current.GetSharePointContext(httpContext) != null)
{
return RedirectionStatus.Ok;
}
const string SPHasRedirectedToSharePointKey = "SPHasRedirectedToSharePoint";
if (!string.IsNullOrEmpty(httpContext.Request.QueryString[SPHasRedirectedToSharePointKey]))
{
return RedirectionStatus.CanNotRedirect;
}
Uri spHostUrl = SharePointContext.GetSPHostUrl(httpContext.Request);
if (spHostUrl == null)
{
return RedirectionStatus.CanNotRedirect;
}
if (StringComparer.OrdinalIgnoreCase.Equals(httpContext.Request.HttpMethod, "POST"))
{
return RedirectionStatus.CanNotRedirect;
}
Uri requestUrl = httpContext.Request.Url;
var queryNameValueCollection = HttpUtility.ParseQueryString(requestUrl.Query);
// Removes the values that are included in {StandardTokens}, as {StandardTokens} will be inserted at the beginning of the query string.
queryNameValueCollection.Remove(SharePointContext.SPHostUrlKey);
queryNameValueCollection.Remove(SharePointContext.SPAppWebUrlKey);
queryNameValueCollection.Remove(SharePointContext.SPLanguageKey);
queryNameValueCollection.Remove(SharePointContext.SPClientTagKey);
queryNameValueCollection.Remove(SharePointContext.SPProductNumberKey);
// Adds SPHasRedirectedToSharePoint=1.
queryNameValueCollection.Add(SPHasRedirectedToSharePointKey, "1");
UriBuilder returnUrlBuilder = new UriBuilder(requestUrl);
returnUrlBuilder.Query = queryNameValueCollection.ToString();
// Inserts StandardTokens.
const string StandardTokens = "{StandardTokens}";
string returnUrlString = returnUrlBuilder.Uri.AbsoluteUri;
returnUrlString = returnUrlString.Insert(returnUrlString.IndexOf("?") + 1, StandardTokens + "&");
// Constructs redirect url.
string redirectUrlString = TokenHelper.GetAppContextTokenRequestUrl(spHostUrl.AbsoluteUri, Uri.EscapeDataString(returnUrlString));
redirectUrl = new Uri(redirectUrlString, UriKind.Absolute);
return RedirectionStatus.ShouldRedirect;
}
/// <summary>
/// Checks if it is necessary to redirect to SharePoint for user to authenticate.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <param name="redirectUrl">The redirect url to SharePoint if the status is ShouldRedirect. <c>Null</c> if the status is Ok or CanNotRedirect.</param>
/// <returns>Redirection status.</returns>
public static RedirectionStatus CheckRedirectionStatus(HttpContext httpContext, out Uri redirectUrl)
{
return CheckRedirectionStatus(new HttpContextWrapper(httpContext), out redirectUrl);
}
/// <summary>
/// Creates a SharePointContext instance with the specified HTTP request.
/// </summary>
/// <param name="httpRequest">The HTTP request.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if errors occur.</returns>
public SharePointContext CreateSharePointContext(HttpRequestBase httpRequest)
{
if (httpRequest == null)
{
throw new ArgumentNullException("httpRequest");
}
// SPHostUrl
Uri spHostUrl = SharePointContext.GetSPHostUrl(httpRequest);
if (spHostUrl == null)
{
return null;
}
// SPAppWebUrl
string spAppWebUrlString = TokenHelper.EnsureTrailingSlash(httpRequest.QueryString[SharePointContext.SPAppWebUrlKey]);
Uri spAppWebUrl;
if (!Uri.TryCreate(spAppWebUrlString, UriKind.Absolute, out spAppWebUrl) ||
!(spAppWebUrl.Scheme == Uri.UriSchemeHttp || spAppWebUrl.Scheme == Uri.UriSchemeHttps))
{
spAppWebUrl = null;
}
// SPLanguage
string spLanguage = httpRequest.QueryString[SharePointContext.SPLanguageKey];
if (string.IsNullOrEmpty(spLanguage))
{
return null;
}
// SPClientTag
string spClientTag = httpRequest.QueryString[SharePointContext.SPClientTagKey];
if (string.IsNullOrEmpty(spClientTag))
{
return null;
}
// SPProductNumber
string spProductNumber = httpRequest.QueryString[SharePointContext.SPProductNumberKey];
if (string.IsNullOrEmpty(spProductNumber))
{
return null;
}
return CreateSharePointContext(spHostUrl, spAppWebUrl, spLanguage, spClientTag, spProductNumber, httpRequest);
}
/// <summary>
/// Creates a SharePointContext instance with the specified HTTP request.
/// </summary>
/// <param name="httpRequest">The HTTP request.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if errors occur.</returns>
public SharePointContext CreateSharePointContext(HttpRequest httpRequest)
{
return CreateSharePointContext(new HttpRequestWrapper(httpRequest));
}
/// <summary>
/// Gets a SharePointContext instance associated with the specified HTTP context.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if not found and a new instance can't be created.</returns>
public SharePointContext GetSharePointContext(HttpContextBase httpContext)
{
if (httpContext == null)
{
throw new ArgumentNullException("httpContext");
}
Uri spHostUrl = SharePointContext.GetSPHostUrl(httpContext.Request);
if (spHostUrl == null)
{
return null;
}
SharePointContext spContext = LoadSharePointContext(httpContext);
if (spContext == null || !ValidateSharePointContext(spContext, httpContext))
{
spContext = CreateSharePointContext(httpContext.Request);
if (spContext != null)
{
SaveSharePointContext(spContext, httpContext);
}
}
return spContext;
}
/// <summary>
/// Gets a SharePointContext instance associated with the specified HTTP context.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if not found and a new instance can't be created.</returns>
public SharePointContext GetSharePointContext(HttpContext httpContext)
{
return GetSharePointContext(new HttpContextWrapper(httpContext));
}
/// <summary>
/// Creates a SharePointContext instance.
/// </summary>
/// <param name="spHostUrl">The SharePoint host url.</param>
/// <param name="spAppWebUrl">The SharePoint app web url.</param>
/// <param name="spLanguage">The SharePoint language.</param>
/// <param name="spClientTag">The SharePoint client tag.</param>
/// <param name="spProductNumber">The SharePoint product number.</param>
/// <param name="httpRequest">The HTTP request.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if errors occur.</returns>
protected abstract SharePointContext CreateSharePointContext(Uri spHostUrl, Uri spAppWebUrl, string spLanguage, string spClientTag, string spProductNumber, HttpRequestBase httpRequest);
/// <summary>
/// Validates if the given SharePointContext can be used with the specified HTTP context.
/// </summary>
/// <param name="spContext">The SharePointContext.</param>
/// <param name="httpContext">The HTTP context.</param>
/// <returns>True if the given SharePointContext can be used with the specified HTTP context.</returns>
protected abstract bool ValidateSharePointContext(SharePointContext spContext, HttpContextBase httpContext);
/// <summary>
/// Loads the SharePointContext instance associated with the specified HTTP context.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <returns>The SharePointContext instance. Returns <c>null</c> if not found.</returns>
protected abstract SharePointContext LoadSharePointContext(HttpContextBase httpContext);
/// <summary>
/// Saves the specified SharePointContext instance associated with the specified HTTP context.
/// <c>null</c> is accepted for clearing the SharePointContext instance associated with the HTTP context.
/// </summary>
/// <param name="spContext">The SharePointContext instance to be saved, or <c>null</c>.</param>
/// <param name="httpContext">The HTTP context.</param>
protected abstract void SaveSharePointContext(SharePointContext spContext, HttpContextBase httpContext);
}
#region ACS
/// <summary>
/// Encapsulates all the information from SharePoint in ACS mode.
/// </summary>
public class SharePointAcsContext : SharePointContext
{
private readonly string contextToken;
private readonly SharePointContextToken contextTokenObj;
/// <summary>
/// The context token.
/// </summary>
public string ContextToken
{
get { return this.contextTokenObj.ValidTo > DateTime.UtcNow ? this.contextToken : null; }
}
/// <summary>
/// The context token's "CacheKey" claim.
/// </summary>
public string CacheKey
{
get { return this.contextTokenObj.ValidTo > DateTime.UtcNow ? this.contextTokenObj.CacheKey : null; }
}
/// <summary>
/// The context token's "refreshtoken" claim.
/// </summary>
public string RefreshToken
{
get { return this.contextTokenObj.ValidTo > DateTime.UtcNow ? this.contextTokenObj.RefreshToken : null; }
}
public override string UserAccessTokenForSPHost
{
get
{
return GetAccessTokenString(ref this.userAccessTokenForSPHost,
() => TokenHelper.GetAccessToken(this.contextTokenObj, this.SPHostUrl.Authority));
}
}
public override string UserAccessTokenForSPAppWeb
{
get
{
if (this.SPAppWebUrl == null)
{
return null;
}
return GetAccessTokenString(ref this.userAccessTokenForSPAppWeb,
() => TokenHelper.GetAccessToken(this.contextTokenObj, this.SPAppWebUrl.Authority));
}
}
public override string AppOnlyAccessTokenForSPHost
{
get
{
return GetAccessTokenString(ref this.appOnlyAccessTokenForSPHost,
() => TokenHelper.GetAppOnlyAccessToken(TokenHelper.SharePointPrincipal, this.SPHostUrl.Authority, TokenHelper.GetRealmFromTargetUrl(this.SPHostUrl)));
}
}
public override string AppOnlyAccessTokenForSPAppWeb
{
get
{
if (this.SPAppWebUrl == null)
{
return null;
}
return GetAccessTokenString(ref this.appOnlyAccessTokenForSPAppWeb,
() => TokenHelper.GetAppOnlyAccessToken(TokenHelper.SharePointPrincipal, this.SPAppWebUrl.Authority, TokenHelper.GetRealmFromTargetUrl(this.SPAppWebUrl)));
}
}
public SharePointAcsContext(Uri spHostUrl, Uri spAppWebUrl, string spLanguage, string spClientTag, string spProductNumber, string contextToken, SharePointContextToken contextTokenObj)
: base(spHostUrl, spAppWebUrl, spLanguage, spClientTag, spProductNumber)
{
if (string.IsNullOrEmpty(contextToken))
{
throw new ArgumentNullException("contextToken");
}
if (contextTokenObj == null)
{
throw new ArgumentNullException("contextTokenObj");
}
this.contextToken = contextToken;
this.contextTokenObj = contextTokenObj;
}
/// <summary>
/// Ensures the access token is valid and returns it.
/// </summary>
/// <param name="accessToken">The access token to verify.</param>
/// <param name="tokenRenewalHandler">The token renewal handler.</param>
/// <returns>The access token string.</returns>
private static string GetAccessTokenString(ref Tuple<string, DateTime> accessToken, Func<OAuth2AccessTokenResponse> tokenRenewalHandler)
{
RenewAccessTokenIfNeeded(ref accessToken, tokenRenewalHandler);
return IsAccessTokenValid(accessToken) ? accessToken.Item1 : null;
}
/// <summary>
/// Renews the access token if it is not valid.
/// </summary>
/// <param name="accessToken">The access token to renew.</param>
/// <param name="tokenRenewalHandler">The token renewal handler.</param>
private static void RenewAccessTokenIfNeeded(ref Tuple<string, DateTime> accessToken, Func<OAuth2AccessTokenResponse> tokenRenewalHandler)
{
if (IsAccessTokenValid(accessToken))
{
return;
}
try
{
OAuth2AccessTokenResponse oAuth2AccessTokenResponse = tokenRenewalHandler();
DateTime expiresOn = oAuth2AccessTokenResponse.ExpiresOn;
if ((expiresOn - oAuth2AccessTokenResponse.NotBefore) > AccessTokenLifetimeTolerance)
{
// Make the access token get renewed a bit earlier than the time when it expires
// so that the calls to SharePoint with it will have enough time to complete successfully.
expiresOn -= AccessTokenLifetimeTolerance;
}
accessToken = Tuple.Create(oAuth2AccessTokenResponse.AccessToken, expiresOn);
}
catch (WebException)
{
}
}
}
/// <summary>
/// Default provider for SharePointAcsContext.
/// </summary>
public class SharePointAcsContextProvider : SharePointContextProvider
{
private const string SPContextKey = "SPContext";
private const string SPCacheKeyKey = "SPCacheKey";
protected override SharePointContext CreateSharePointContext(Uri spHostUrl, Uri spAppWebUrl, string spLanguage, string spClientTag, string spProductNumber, HttpRequestBase httpRequest)
{
string contextTokenString = TokenHelper.GetContextTokenFromRequest(httpRequest);
if (string.IsNullOrEmpty(contextTokenString))
{
return null;
}
SharePointContextToken contextToken = null;
try
{
contextToken = TokenHelper.ReadAndValidateContextToken(contextTokenString, httpRequest.Url.Authority);
}
catch (WebException)
{
return null;
}
catch (AudienceUriValidationFailedException)
{
return null;
}
return new SharePointAcsContext(spHostUrl, spAppWebUrl, spLanguage, spClientTag, spProductNumber, contextTokenString, contextToken);
}
protected override bool ValidateSharePointContext(SharePointContext spContext, HttpContextBase httpContext)
{
SharePointAcsContext spAcsContext = spContext as SharePointAcsContext;
if (spAcsContext != null)
{
Uri spHostUrl = SharePointContext.GetSPHostUrl(httpContext.Request);
string contextToken = TokenHelper.GetContextTokenFromRequest(httpContext.Request);
HttpCookie spCacheKeyCookie = httpContext.Request.Cookies[SPCacheKeyKey];
string spCacheKey = spCacheKeyCookie != null ? spCacheKeyCookie.Value : null;
return spHostUrl == spAcsContext.SPHostUrl &&
!string.IsNullOrEmpty(spAcsContext.CacheKey) &&
spCacheKey == spAcsContext.CacheKey &&
!string.IsNullOrEmpty(spAcsContext.ContextToken) &&
(string.IsNullOrEmpty(contextToken) || contextToken == spAcsContext.ContextToken);
}
return false;
}
protected override SharePointContext LoadSharePointContext(HttpContextBase httpContext)
{
return httpContext.Session[SPContextKey] as SharePointAcsContext;
}
protected override void SaveSharePointContext(SharePointContext spContext, HttpContextBase httpContext)
{
SharePointAcsContext spAcsContext = spContext as SharePointAcsContext;
if (spAcsContext != null)
{
HttpCookie spCacheKeyCookie = new HttpCookie(SPCacheKeyKey)
{
Value = spAcsContext.CacheKey,
Secure = true,
HttpOnly = true
};
httpContext.Response.AppendCookie(spCacheKeyCookie);
}
httpContext.Session[SPContextKey] = spAcsContext;
}
}
#endregion ACS
#region HighTrust
/// <summary>
/// Encapsulates all the information from SharePoint in HighTrust mode.
/// </summary>
public class SharePointHighTrustContext : SharePointContext
{
private readonly WindowsIdentity logonUserIdentity;
/// <summary>
/// The Windows identity for the current user.
/// </summary>
public WindowsIdentity LogonUserIdentity
{
get { return this.logonUserIdentity; }
}
public override string UserAccessTokenForSPHost
{
get
{
return GetAccessTokenString(ref this.userAccessTokenForSPHost,
() => TokenHelper.GetS2SAccessTokenWithWindowsIdentity(this.SPHostUrl, this.LogonUserIdentity));
}
}
public override string UserAccessTokenForSPAppWeb
{
get
{
if (this.SPAppWebUrl == null)
{
return null;
}
return GetAccessTokenString(ref this.userAccessTokenForSPAppWeb,
() => TokenHelper.GetS2SAccessTokenWithWindowsIdentity(this.SPAppWebUrl, this.LogonUserIdentity));
}
}
public override string AppOnlyAccessTokenForSPHost
{
get
{
return GetAccessTokenString(ref this.appOnlyAccessTokenForSPHost,
() => TokenHelper.GetS2SAccessTokenWithWindowsIdentity(this.SPHostUrl, null));
}
}
public override string AppOnlyAccessTokenForSPAppWeb
{
get
{
if (this.SPAppWebUrl == null)
{
return null;
}
return GetAccessTokenString(ref this.appOnlyAccessTokenForSPAppWeb,
() => TokenHelper.GetS2SAccessTokenWithWindowsIdentity(this.SPAppWebUrl, null));
}
}
public SharePointHighTrustContext(Uri spHostUrl, Uri spAppWebUrl, string spLanguage, string spClientTag, string spProductNumber, WindowsIdentity logonUserIdentity)
: base(spHostUrl, spAppWebUrl, spLanguage, spClientTag, spProductNumber)
{
if (logonUserIdentity == null)
{
throw new ArgumentNullException("logonUserIdentity");
}
this.logonUserIdentity = logonUserIdentity;
}
/// <summary>
/// Ensures the access token is valid and returns it.
/// </summary>
/// <param name="accessToken">The access token to verify.</param>
/// <param name="tokenRenewalHandler">The token renewal handler.</param>
/// <returns>The access token string.</returns>
private static string GetAccessTokenString(ref Tuple<string, DateTime> accessToken, Func<string> tokenRenewalHandler)
{
RenewAccessTokenIfNeeded(ref accessToken, tokenRenewalHandler);
return IsAccessTokenValid(accessToken) ? accessToken.Item1 : null;
}
/// <summary>
/// Renews the access token if it is not valid.
/// </summary>
/// <param name="accessToken">The access token to renew.</param>
/// <param name="tokenRenewalHandler">The token renewal handler.</param>
private static void RenewAccessTokenIfNeeded(ref Tuple<string, DateTime> accessToken, Func<string> tokenRenewalHandler)
{
if (IsAccessTokenValid(accessToken))
{
return;
}
DateTime expiresOn = DateTime.UtcNow.Add(TokenHelper.HighTrustAccessTokenLifetime);
if (TokenHelper.HighTrustAccessTokenLifetime > AccessTokenLifetimeTolerance)
{
// Make the access token get renewed a bit earlier than the time when it expires
// so that the calls to SharePoint with it will have enough time to complete successfully.
expiresOn -= AccessTokenLifetimeTolerance;
}
accessToken = Tuple.Create(tokenRenewalHandler(), expiresOn);
}
}
/// <summary>
/// Default provider for SharePointHighTrustContext.
/// </summary>
public class SharePointHighTrustContextProvider : SharePointContextProvider
{
private const string SPContextKey = "SPContext";
protected override SharePointContext CreateSharePointContext(Uri spHostUrl, Uri spAppWebUrl, string spLanguage, string spClientTag, string spProductNumber, HttpRequestBase httpRequest)
{
WindowsIdentity logonUserIdentity = httpRequest.LogonUserIdentity;
if (logonUserIdentity == null || !logonUserIdentity.IsAuthenticated || logonUserIdentity.IsGuest || logonUserIdentity.User == null)
{
return null;
}
return new SharePointHighTrustContext(spHostUrl, spAppWebUrl, spLanguage, spClientTag, spProductNumber, logonUserIdentity);
}
protected override bool ValidateSharePointContext(SharePointContext spContext, HttpContextBase httpContext)
{
SharePointHighTrustContext spHighTrustContext = spContext as SharePointHighTrustContext;
if (spHighTrustContext != null)
{
Uri spHostUrl = SharePointContext.GetSPHostUrl(httpContext.Request);
WindowsIdentity logonUserIdentity = httpContext.Request.LogonUserIdentity;
return spHostUrl == spHighTrustContext.SPHostUrl &&
logonUserIdentity != null &&
logonUserIdentity.IsAuthenticated &&
!logonUserIdentity.IsGuest &&
logonUserIdentity.User == spHighTrustContext.LogonUserIdentity.User;
}
return false;
}
protected override SharePointContext LoadSharePointContext(HttpContextBase httpContext)
{
return httpContext.Session[SPContextKey] as SharePointHighTrustContext;
}
protected override void SaveSharePointContext(SharePointContext spContext, HttpContextBase httpContext)
{
httpContext.Session[SPContextKey] = spContext as SharePointHighTrustContext;
}
}
#endregion HighTrust
}
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