net/http/http_auth_sspi_win.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // This file contains common routines used by NTLM and Negotiate authentication
   6 // using the SSPI API on Windows.
   7
   8 #ifndef NET_HTTP_HTTP_AUTH_SSPI_WIN_H_
   9 #define NET_HTTP_HTTP_AUTH_SSPI_WIN_H_
  10
  11 // security.h needs to be included for CredHandle. Unfortunately CredHandle
  12 // is a typedef and can't be forward declared.
  13 #define SECURITY_WIN32 1
  14 #include <windows.h>
  15 #include <security.h>
  16
  17 #include <string>
  18
  19 #include "base/strings/string16.h"
  20 #include "net/base/net_export.h"
  21 #include "net/http/http_auth.h"
  22
  23 namespace net {
  24
  25 // SSPILibrary is introduced so unit tests can mock the calls to Windows' SSPI
  26 // implementation. The default implementation simply passes the arguments on to
  27 // the SSPI implementation provided by Secur32.dll.
  28 // NOTE(cbentzel): I considered replacing the Secur32.dll with a mock DLL, but
  29 // decided that it wasn't worth the effort as this is unlikely to be performance
  30 // sensitive code.
  31 class SSPILibrary {
  32  public:
  33   virtual ~SSPILibrary() {}
  34
  35   virtual SECURITY_STATUS AcquireCredentialsHandle(LPWSTR pszPrincipal,
  36                                                    LPWSTR pszPackage,
  37                                                    unsigned long fCredentialUse,
  38                                                    void* pvLogonId,
  39                                                    void* pvAuthData,
  40                                                    SEC_GET_KEY_FN pGetKeyFn,
  41                                                    void* pvGetKeyArgument,
  42                                                    PCredHandle phCredential,
  43                                                    PTimeStamp ptsExpiry) = 0;
  44
  45   virtual SECURITY_STATUS InitializeSecurityContext(PCredHandle phCredential,
  46                                                     PCtxtHandle phContext,
  47                                                     SEC_WCHAR* pszTargetName,
  48                                                     unsigned long fContextReq,
  49                                                     unsigned long Reserved1,
  50                                                     unsigned long TargetDataRep,
  51                                                     PSecBufferDesc pInput,
  52                                                     unsigned long Reserved2,
  53                                                     PCtxtHandle phNewContext,
  54                                                     PSecBufferDesc pOutput,
  55                                                     unsigned long* contextAttr,
  56                                                     PTimeStamp ptsExpiry) = 0;
  57
  58   virtual SECURITY_STATUS QuerySecurityPackageInfo(LPWSTR pszPackageName,
  59                                                    PSecPkgInfoW *pkgInfo) = 0;
  60
  61   virtual SECURITY_STATUS FreeCredentialsHandle(PCredHandle phCredential) = 0;
  62
  63   virtual SECURITY_STATUS DeleteSecurityContext(PCtxtHandle phContext) = 0;
  64
  65   virtual SECURITY_STATUS FreeContextBuffer(PVOID pvContextBuffer) = 0;
  66 };
  67
  68 class SSPILibraryDefault : public SSPILibrary {
  69  public:
  70   SSPILibraryDefault() {}
  71   virtual ~SSPILibraryDefault() {}
  72
  73   virtual SECURITY_STATUS AcquireCredentialsHandle(LPWSTR pszPrincipal,
  74                                                    LPWSTR pszPackage,
  75                                                    unsigned long fCredentialUse,
  76                                                    void* pvLogonId,
  77                                                    void* pvAuthData,
  78                                                    SEC_GET_KEY_FN pGetKeyFn,
  79                                                    void* pvGetKeyArgument,
  80                                                    PCredHandle phCredential,
  81                                                    PTimeStamp ptsExpiry) {
  82     return ::AcquireCredentialsHandle(pszPrincipal, pszPackage, fCredentialUse,
  83                                       pvLogonId, pvAuthData, pGetKeyFn,
  84                                       pvGetKeyArgument, phCredential,
  85                                       ptsExpiry);
  86   }
  87
  88   virtual SECURITY_STATUS InitializeSecurityContext(PCredHandle phCredential,
  89                                                     PCtxtHandle phContext,
  90                                                     SEC_WCHAR* pszTargetName,
  91                                                     unsigned long fContextReq,
  92                                                     unsigned long Reserved1,
  93                                                     unsigned long TargetDataRep,
  94                                                     PSecBufferDesc pInput,
  95                                                     unsigned long Reserved2,
  96                                                     PCtxtHandle phNewContext,
  97                                                     PSecBufferDesc pOutput,
  98                                                     unsigned long* contextAttr,
  99                                                     PTimeStamp ptsExpiry) {
 100     return ::InitializeSecurityContext(phCredential, phContext, pszTargetName,
 101                                        fContextReq, Reserved1, TargetDataRep,
 102                                        pInput, Reserved2, phNewContext, pOutput,
 103                                        contextAttr, ptsExpiry);
 104   }
 105
 106   virtual SECURITY_STATUS QuerySecurityPackageInfo(LPWSTR pszPackageName,
 107                                                    PSecPkgInfoW *pkgInfo) {
 108     return ::QuerySecurityPackageInfo(pszPackageName, pkgInfo);
 109   }
 110
 111   virtual SECURITY_STATUS FreeCredentialsHandle(PCredHandle phCredential) {
 112     return ::FreeCredentialsHandle(phCredential);
 113   }
 114
 115   virtual SECURITY_STATUS DeleteSecurityContext(PCtxtHandle phContext) {
 116     return ::DeleteSecurityContext(phContext);
 117   }
 118
 119   virtual SECURITY_STATUS FreeContextBuffer(PVOID pvContextBuffer) {
 120     return ::FreeContextBuffer(pvContextBuffer);
 121   }
 122 };
 123
 124 class NET_EXPORT_PRIVATE HttpAuthSSPI {
 125  public:
 126   HttpAuthSSPI(SSPILibrary* sspi_library,
 127                const std::string& scheme,
 128                const SEC_WCHAR* security_package,
 129                ULONG max_token_length);
 130   ~HttpAuthSSPI();
 131
 132   bool NeedsIdentity() const;
 133
 134   bool AllowsExplicitCredentials() const;
 135
 136   HttpAuth::AuthorizationResult ParseChallenge(
 137       HttpAuth::ChallengeTokenizer* tok);
 138
 139   // Generates an authentication token for the service specified by the
 140   // Service Principal Name |spn| and stores the value in |*auth_token|.
 141   // If the return value is not |OK|, then the value of |*auth_token| is
 142   // unspecified. ERR_IO_PENDING is not a valid return code.
 143   // If this is the first round of a multiple round scheme, credentials are
 144   // obtained using |*credentials|. If |credentials| is NULL, the credentials
 145   // for the currently logged in user are used instead.
 146   int GenerateAuthToken(const AuthCredentials* credentials,
 147                         const std::wstring& spn,
 148                         std::string* auth_token);
 149
 150   // Delegation is allowed on the Kerberos ticket. This allows certain servers
 151   // to act as the user, such as an IIS server retrieiving data from a
 152   // Kerberized MSSQL server.
 153   void Delegate();
 154
 155  private:
 156   int OnFirstRound(const AuthCredentials* credentials);
 157
 158   int GetNextSecurityToken(
 159       const std::wstring& spn,
 160       const void* in_token,
 161       int in_token_len,
 162       void** out_token,
 163       int* out_token_len);
 164
 165   void ResetSecurityContext();
 166
 167   SSPILibrary* library_;
 168   std::string scheme_;
 169   const SEC_WCHAR* security_package_;
 170   std::string decoded_server_auth_token_;
 171   ULONG max_token_length_;
 172   CredHandle cred_;
 173   CtxtHandle ctxt_;
 174   bool can_delegate_;
 175 };
 176
 177 // Splits |combined| into domain and username.
 178 // If |combined| is of form "FOO\bar", |domain| will contain "FOO" and |user|
 179 // will contain "bar".
 180 // If |combined| is of form "bar", |domain| will be empty and |user| will
 181 // contain "bar".
 182 // |domain| and |user| must be non-NULL.
 183 NET_EXPORT_PRIVATE void SplitDomainAndUser(const base::string16& combined,
 184                                            base::string16* domain,
 185                                            base::string16* user);
 186
 187 // Determines the maximum token length in bytes for a particular SSPI package.
 188 //
 189 // |library| and |max_token_length| must be non-NULL pointers to valid objects.
 190 //
 191 // If the return value is OK, |*max_token_length| contains the maximum token
 192 // length in bytes.
 193 //
 194 // If the return value is ERR_UNSUPPORTED_AUTH_SCHEME, |package| is not an
 195 // known SSPI authentication scheme on this system. |*max_token_length| is not
 196 // changed.
 197 //
 198 // If the return value is ERR_UNEXPECTED, there was an unanticipated problem
 199 // in the underlying SSPI call. The details are logged, and |*max_token_length|
 200 // is not changed.
 201 NET_EXPORT_PRIVATE int DetermineMaxTokenLength(SSPILibrary* library,
 202                                                const std::wstring& package,
 203                                                ULONG* max_token_length);
 204
 205 }  // namespace net
 206
 207 #endif  // NET_HTTP_HTTP_AUTH_SSPI_WIN_H_