content/base/public/nsContentPolicyUtils.h

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   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
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   8  * http://www.mozilla.org/MPL/
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  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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  13  * License.
  14  *
  15  * The Original Code is Mozilla code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Zero-Knowledge Systems, Inc.
  19  * Portions created by the Initial Developer are Copyright (C) 2000
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Timothy Watt <riceman+moz@mail.rit.edu>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either of the GNU General Public License Version 2 or later (the "GPL"),
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  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 /*
  40  * Utility routines for checking content load/process policy settings,
  41  * and routines helpful for content policy implementors.
  42  *
  43  * XXXbz it would be nice if some of this stuff could be out-of-lined in
  44  * nsContentUtils.  That would work for almost all the callers...
  45  */
  46
  47 #ifndef __nsContentPolicyUtils_h__
  48 #define __nsContentPolicyUtils_h__
  49
  50 #include "nsIContentPolicy.h"
  51 #include "nsIServiceManager.h"
  52 #include "nsIContent.h"
  53 #include "nsIScriptSecurityManager.h"
  54 #include "nsIPrincipal.h"
  55
  56 //XXXtw sadly, this makes consumers of nsContentPolicyUtils depend on widget
  57 #include "nsIDocument.h"
  58 #include "nsPIDOMWindow.h"
  59
  60 class nsACString;
  61
  62 #define NS_CONTENTPOLICY_CONTRACTID   "@mozilla.org/layout/content-policy;1"
  63 #define NS_CONTENTPOLICY_CATEGORY "content-policy"
  64 #define NS_CONTENTPOLICY_CID                              \
  65   {0x0e3afd3d, 0xeb60, 0x4c2b,                            \
  66      { 0x96, 0x3b, 0x56, 0xd7, 0xc4, 0x39, 0xf1, 0x24 }}
  67
  68 /**
  69  * Evaluates to true if val is ACCEPT.
  70  *
  71  * @param val the status returned from shouldProcess/shouldLoad
  72  */
  73 #define NS_CP_ACCEPTED(val) ((val) == nsIContentPolicy::ACCEPT)
  74
  75 /**
  76  * Evaluates to true if val is a REJECT_* status
  77  *
  78  * @param val the status returned from shouldProcess/shouldLoad
  79  */
  80 #define NS_CP_REJECTED(val) ((val) != nsIContentPolicy::ACCEPT)
  81
  82 // Offer convenient translations of constants -> const char*
  83
  84 // convenience macro to reduce some repetative typing...
  85 // name is the name of a constant from this interface
  86 #define CASE_RETURN(name)          \
  87   case nsIContentPolicy:: name :   \
  88     return #name
  89
  90 #ifdef PR_LOGGING
  91 /**
  92  * Returns a string corresponding to the name of the response constant, or
  93  * "<Unknown Response>" if an unknown response value is given.
  94  *
  95  * The return value is static and must not be freed.
  96  *
  97  * @param response the response code
  98  * @return the name of the given response code
  99  */
 100 inline const char *
 101 NS_CP_ResponseName(PRInt16 response)
 102 {
 103   switch (response) {
 104     CASE_RETURN( REJECT_REQUEST );
 105     CASE_RETURN( REJECT_TYPE    );
 106     CASE_RETURN( REJECT_SERVER  );
 107     CASE_RETURN( REJECT_OTHER   );
 108     CASE_RETURN( ACCEPT         );
 109   default:
 110     return "<Unknown Response>";
 111   }
 112 }
 113
 114 /**
 115  * Returns a string corresponding to the name of the content type constant, or
 116  * "<Unknown Type>" if an unknown content type value is given.
 117  *
 118  * The return value is static and must not be freed.
 119  *
 120  * @param contentType the content type code
 121  * @return the name of the given content type code
 122  */
 123 inline const char *
 124 NS_CP_ContentTypeName(PRUint32 contentType)
 125 {
 126   switch (contentType) {
 127     CASE_RETURN( TYPE_OTHER             );
 128     CASE_RETURN( TYPE_SCRIPT            );
 129     CASE_RETURN( TYPE_IMAGE             );
 130     CASE_RETURN( TYPE_STYLESHEET        );
 131     CASE_RETURN( TYPE_OBJECT            );
 132     CASE_RETURN( TYPE_DOCUMENT          );
 133     CASE_RETURN( TYPE_SUBDOCUMENT       );
 134     CASE_RETURN( TYPE_REFRESH           );
 135     CASE_RETURN( TYPE_XBL               );
 136     CASE_RETURN( TYPE_PING              );
 137     CASE_RETURN( TYPE_XMLHTTPREQUEST    );
 138     CASE_RETURN( TYPE_OBJECT_SUBREQUEST );
 139     CASE_RETURN( TYPE_DTD               );
 140     CASE_RETURN( TYPE_FONT              );
 141    default:
 142     return "<Unknown Type>";
 143   }
 144 }
 145
 146 #endif // defined(PR_LOGGING)
 147
 148 #undef CASE_RETURN
 149
 150 /* Passes on parameters from its "caller"'s context. */
 151 #define CHECK_CONTENT_POLICY(action)                                          \
 152   PR_BEGIN_MACRO                                                              \
 153     nsCOMPtr<nsIContentPolicy> policy =                                       \
 154          do_GetService(NS_CONTENTPOLICY_CONTRACTID);                          \
 155     if (!policy)                                                              \
 156         return NS_ERROR_FAILURE;                                              \
 157                                                                               \
 158     return policy-> action (contentType, contentLocation, requestOrigin,      \
 159                             context, mimeType, extra, decision);              \
 160   PR_END_MACRO
 161
 162 /* Passes on parameters from its "caller"'s context. */
 163 #define CHECK_CONTENT_POLICY_WITH_SERVICE(action, _policy)                    \
 164   PR_BEGIN_MACRO                                                              \
 165     return _policy-> action (contentType, contentLocation, requestOrigin,     \
 166                              context, mimeType, extra, decision);             \
 167   PR_END_MACRO
 168
 169 /**
 170  * Check whether we can short-circuit this check and bail out.  If not, get the
 171  * origin URI to use.
 172  *
 173  * Note: requestOrigin is scoped outside the PR_BEGIN_MACRO/PR_END_MACRO on
 174  * purpose */
 175 #define CHECK_PRINCIPAL                                                       \
 176   nsCOMPtr<nsIURI> requestOrigin;                                             \
 177   PR_BEGIN_MACRO                                                              \
 178   if (originPrincipal) {                                                      \
 179       nsCOMPtr<nsIScriptSecurityManager> secMan = aSecMan;                    \
 180       if (!secMan) {                                                          \
 181           secMan = do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID);        \
 182       }                                                                       \
 183       if (secMan) {                                                           \
 184           PRBool isSystem;                                                    \
 185           nsresult rv = secMan->IsSystemPrincipal(originPrincipal,            \
 186                                                   &isSystem);                 \
 187           NS_ENSURE_SUCCESS(rv, rv);                                          \
 188           if (isSystem) {                                                     \
 189               *decision = nsIContentPolicy::ACCEPT;                           \
 190               return NS_OK;                                                   \
 191           }                                                                   \
 192       }                                                                       \
 193       nsresult rv = originPrincipal->GetURI(getter_AddRefs(requestOrigin));   \
 194       NS_ENSURE_SUCCESS(rv, rv);                                              \
 195   }                                                                           \
 196   PR_END_MACRO
 197
 198 /**
 199  * Alias for calling ShouldLoad on the content policy service.  Parameters are
 200  * the same as nsIContentPolicy::shouldLoad, except for the originPrincipal
 201  * parameter, which should be non-null if possible, and the last two
 202  * parameters, which can be used to pass in pointer to some useful services if
 203  * the caller already has them.  The origin URI to pass to shouldLoad will be
 204  * the URI of originPrincipal, unless originPrincipal is null (in which case a
 205  * null origin URI will be passed).
 206  */
 207 inline nsresult
 208 NS_CheckContentLoadPolicy(PRUint32          contentType,
 209                           nsIURI           *contentLocation,
 210                           nsIPrincipal     *originPrincipal,
 211                           nsISupports      *context,
 212                           const nsACString &mimeType,
 213                           nsISupports      *extra,
 214                           PRInt16          *decision,
 215                           nsIContentPolicy *policyService = nsnull,
 216                           nsIScriptSecurityManager* aSecMan = nsnull)
 217 {
 218     CHECK_PRINCIPAL;
 219     if (policyService) {
 220         CHECK_CONTENT_POLICY_WITH_SERVICE(ShouldLoad, policyService);
 221     }
 222     CHECK_CONTENT_POLICY(ShouldLoad);
 223 }
 224
 225 /**
 226  * Alias for calling ShouldProcess on the content policy service.  Parameters
 227  * are the same as nsIContentPolicy::shouldLoad, except for the originPrincipal
 228  * parameter, which should be non-null if possible, and the last two
 229  * parameters, which can be used to pass in pointer to some useful services if
 230  * the caller already has them.  The origin URI to pass to shouldLoad will be
 231  * the URI of originPrincipal, unless originPrincipal is null (in which case a
 232  * null origin URI will be passed).
 233  */
 234 inline nsresult
 235 NS_CheckContentProcessPolicy(PRUint32          contentType,
 236                              nsIURI           *contentLocation,
 237                              nsIPrincipal     *originPrincipal,
 238                              nsISupports      *context,
 239                              const nsACString &mimeType,
 240                              nsISupports      *extra,
 241                              PRInt16          *decision,
 242                              nsIContentPolicy *policyService = nsnull,
 243                              nsIScriptSecurityManager* aSecMan = nsnull)
 244 {
 245     CHECK_PRINCIPAL;
 246     if (policyService) {
 247         CHECK_CONTENT_POLICY_WITH_SERVICE(ShouldProcess, policyService);
 248     }
 249     CHECK_CONTENT_POLICY(ShouldProcess);
 250 }
 251
 252 #undef CHECK_CONTENT_POLICY
 253 #undef CHECK_CONTENT_POLICY_WITH_SERVICE
 254
 255 /**
 256  * Helper function to get an nsIDocShell given a context.
 257  * If the context is a document or window, the corresponding docshell will be
 258  * returned.
 259  * If the context is a non-document DOM node, the docshell of its ownerDocument
 260  * will be returned.
 261  *
 262  * @param aContext the context to find a docshell for (can be null)
 263  * @return a WEAK pointer to the docshell, or nsnull if it could
 264  *     not be obtained
 265  */
 266 inline nsIDocShell*
 267 NS_CP_GetDocShellFromContext(nsISupports *aContext)
 268 {
 269     if (!aContext) {
 270         return nsnull;
 271     }
 272
 273     nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aContext);
 274
 275     if (!window) {
 276         // our context might be a document (which also QIs to nsIDOMNode), so
 277         // try that first
 278         nsCOMPtr<nsIDocument> doc = do_QueryInterface(aContext);
 279         if (!doc) {
 280             // we were not a document after all, get our ownerDocument,
 281             // hopefully
 282             nsCOMPtr<nsIContent> content = do_QueryInterface(aContext);
 283             if (content) {
 284                 doc = content->GetOwnerDoc();
 285             }
 286         }
 287
 288         if (doc) {
 289             window = doc->GetWindow();
 290         }
 291     }
 292
 293     if (!window) {
 294         return nsnull;
 295     }
 296
 297     return window->GetDocShell();
 298 }
 299
 300 #endif /* __nsContentPolicyUtils_h__ */