DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (426e37b06a75)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * Utility routines for checking content load/process policy settings,
 * and routines helpful for content policy implementors.
 *
 * XXXbz it would be nice if some of this stuff could be out-of-lined in
 * nsContentUtils.  That would work for almost all the callers...
 */

#ifndef __nsContentPolicyUtils_h__
#define __nsContentPolicyUtils_h__

#include "mozilla/BasePrincipal.h"

#include "nsContentUtils.h"
#include "nsIContentPolicy.h"
#include "nsIContent.h"
#include "nsIScriptSecurityManager.h"
#include "nsIURI.h"
#include "nsServiceManagerUtils.h"
#include "nsStringFwd.h"

// XXXtw sadly, this makes consumers of nsContentPolicyUtils depend on widget
#include "mozilla/dom/Document.h"
#include "nsPIDOMWindow.h"

#define NS_CONTENTPOLICY_CONTRACTID "@mozilla.org/layout/content-policy;1"
#define NS_CONTENTPOLICY_CATEGORY "content-policy"
#define NS_CONTENTPOLICY_CID                         \
  {                                                  \
    0x0e3afd3d, 0xeb60, 0x4c2b, {                    \
      0x96, 0x3b, 0x56, 0xd7, 0xc4, 0x39, 0xf1, 0x24 \
    }                                                \
  }

/**
 * Evaluates to true if val is ACCEPT.
 *
 * @param val the status returned from shouldProcess/shouldLoad
 */
#define NS_CP_ACCEPTED(val) ((val) == nsIContentPolicy::ACCEPT)

/**
 * Evaluates to true if val is a REJECT_* status
 *
 * @param val the status returned from shouldProcess/shouldLoad
 */
#define NS_CP_REJECTED(val) ((val) != nsIContentPolicy::ACCEPT)

// Offer convenient translations of constants -> const char*

// convenience macro to reduce some repetative typing...
// name is the name of a constant from this interface
#define CASE_RETURN(name)      \
  case nsIContentPolicy::name: \
    return #name

/**
 * Returns a string corresponding to the name of the response constant, or
 * "<Unknown Response>" if an unknown response value is given.
 *
 * The return value is static and must not be freed.
 *
 * @param response the response code
 * @return the name of the given response code
 */
inline const char* NS_CP_ResponseName(int16_t response) {
  switch (response) {
    CASE_RETURN(REJECT_REQUEST);
    CASE_RETURN(REJECT_TYPE);
    CASE_RETURN(REJECT_SERVER);
    CASE_RETURN(REJECT_OTHER);
    CASE_RETURN(ACCEPT);
    default:
      return "<Unknown Response>";
  }
}

/**
 * Returns a string corresponding to the name of the content type constant, or
 * "<Unknown Type>" if an unknown content type value is given.
 *
 * The return value is static and must not be freed.
 *
 * @param contentType the content type code
 * @return the name of the given content type code
 */
inline const char* NS_CP_ContentTypeName(uint32_t contentType) {
  switch (contentType) {
    CASE_RETURN(TYPE_OTHER);
    CASE_RETURN(TYPE_SCRIPT);
    CASE_RETURN(TYPE_IMAGE);
    CASE_RETURN(TYPE_STYLESHEET);
    CASE_RETURN(TYPE_OBJECT);
    CASE_RETURN(TYPE_DOCUMENT);
    CASE_RETURN(TYPE_SUBDOCUMENT);
    CASE_RETURN(TYPE_REFRESH);
    CASE_RETURN(TYPE_XBL);
    CASE_RETURN(TYPE_PING);
    CASE_RETURN(TYPE_XMLHTTPREQUEST);
    CASE_RETURN(TYPE_OBJECT_SUBREQUEST);
    CASE_RETURN(TYPE_DTD);
    CASE_RETURN(TYPE_FONT);
    CASE_RETURN(TYPE_MEDIA);
    CASE_RETURN(TYPE_WEBSOCKET);
    CASE_RETURN(TYPE_CSP_REPORT);
    CASE_RETURN(TYPE_XSLT);
    CASE_RETURN(TYPE_BEACON);
    CASE_RETURN(TYPE_FETCH);
    CASE_RETURN(TYPE_IMAGESET);
    CASE_RETURN(TYPE_WEB_MANIFEST);
    CASE_RETURN(TYPE_INTERNAL_SCRIPT);
    CASE_RETURN(TYPE_INTERNAL_WORKER);
    CASE_RETURN(TYPE_INTERNAL_SHARED_WORKER);
    CASE_RETURN(TYPE_INTERNAL_EMBED);
    CASE_RETURN(TYPE_INTERNAL_OBJECT);
    CASE_RETURN(TYPE_INTERNAL_FRAME);
    CASE_RETURN(TYPE_INTERNAL_IFRAME);
    CASE_RETURN(TYPE_INTERNAL_AUDIO);
    CASE_RETURN(TYPE_INTERNAL_VIDEO);
    CASE_RETURN(TYPE_INTERNAL_TRACK);
    CASE_RETURN(TYPE_INTERNAL_XMLHTTPREQUEST);
    CASE_RETURN(TYPE_INTERNAL_EVENTSOURCE);
    CASE_RETURN(TYPE_INTERNAL_SERVICE_WORKER);
    CASE_RETURN(TYPE_INTERNAL_SCRIPT_PRELOAD);
    CASE_RETURN(TYPE_INTERNAL_IMAGE);
    CASE_RETURN(TYPE_INTERNAL_IMAGE_PRELOAD);
    CASE_RETURN(TYPE_INTERNAL_IMAGE_FAVICON);
    CASE_RETURN(TYPE_INTERNAL_STYLESHEET);
    CASE_RETURN(TYPE_INTERNAL_STYLESHEET_PRELOAD);
    CASE_RETURN(TYPE_INTERNAL_WORKER_IMPORT_SCRIPTS);
    CASE_RETURN(TYPE_SAVEAS_DOWNLOAD);
    CASE_RETURN(TYPE_SPECULATIVE);
    CASE_RETURN(TYPE_INTERNAL_MODULE);
    CASE_RETURN(TYPE_INTERNAL_MODULE_PRELOAD);
    default:
      return "<Unknown Type>";
  }
}

#undef CASE_RETURN

/* Passes on parameters from its "caller"'s context. */
#define CHECK_CONTENT_POLICY(action)                                    \
  PR_BEGIN_MACRO                                                        \
  nsCOMPtr<nsIContentPolicy> policy =                                   \
      do_GetService(NS_CONTENTPOLICY_CONTRACTID);                       \
  if (!policy) return NS_ERROR_FAILURE;                                 \
                                                                        \
  return policy->action(contentLocation, loadInfo, mimeType, decision); \
  PR_END_MACRO

/* Passes on parameters from its "caller"'s context. */
#define CHECK_CONTENT_POLICY_WITH_SERVICE(action, _policy)               \
  PR_BEGIN_MACRO                                                         \
  return _policy->action(contentLocation, loadInfo, mimeType, decision); \
  PR_END_MACRO

/**
 * Check whether we can short-circuit this check and bail out.  If not, get the
 * origin URI to use.
 *
 * Note: requestOrigin is scoped outside the PR_BEGIN_MACRO/PR_END_MACRO on
 * purpose */
#define CHECK_PRINCIPAL_AND_DATA(action)                                       \
  nsCOMPtr<nsIURI> requestOrigin;                                              \
  PR_BEGIN_MACRO                                                               \
  if (loadingPrincipal) {                                                      \
    /* We exempt most loads into any document with the system principal        \
     * from content policy checks, mostly as an optimization. Which means      \
     * that we need to apply this check to the loading principal, not the      \
     * principal that triggered the load. */                                   \
    bool isSystem = loadingPrincipal->IsSystemPrincipal();                     \
    if (isSystem && contentType != nsIContentPolicy::TYPE_DOCUMENT) {          \
      *decision = nsIContentPolicy::ACCEPT;                                    \
      nsCOMPtr<nsINode> n = do_QueryInterface(context);                        \
      if (!n) {                                                                \
        nsCOMPtr<nsPIDOMWindowOuter> win = do_QueryInterface(context);         \
        n = win ? win->GetExtantDoc() : nullptr;                               \
      }                                                                        \
      if (n) {                                                                 \
        mozilla::dom::Document* d = n->OwnerDoc();                             \
        if (d->IsLoadedAsData() || d->IsBeingUsedAsImage() ||                  \
            d->IsResourceDoc()) {                                              \
          nsCOMPtr<nsIContentPolicy> dataPolicy =                              \
              do_GetService("@mozilla.org/data-document-content-policy;1");    \
          if (dataPolicy) {                                                    \
            dataPolicy->action(contentLocation, loadInfo, mimeType, decision); \
          }                                                                    \
        }                                                                      \
      }                                                                        \
      return NS_OK;                                                            \
    }                                                                          \
    nsresult rv = loadingPrincipal->GetURI(getter_AddRefs(requestOrigin));     \
    NS_ENSURE_SUCCESS(rv, rv);                                                 \
  }                                                                            \
  PR_END_MACRO

/**
 * Alias for calling ShouldLoad on the content policy service.  Parameters are
 * the same as nsIContentPolicy::shouldLoad, except for the loadingPrincipal
 * and triggeringPrincipal parameters (which should be non-null if possible,
 * and have the same semantics as in nsLoadInfo), and the last parameter,
 * which can be used to pass in a pointer to a useful service if the caller
 * already has it.  The origin URI to pass to shouldLoad will be the URI of
 * loadingPrincipal, unless loadingPrincipal is null (in which case a null
 * origin URI will be passed).
 */
inline nsresult NS_CheckContentLoadPolicy(
    nsIURI* contentLocation, nsILoadInfo* loadInfo, const nsACString& mimeType,
    int16_t* decision, nsIContentPolicy* policyService = nullptr) {
  nsIPrincipal* loadingPrincipal = loadInfo->LoadingPrincipal();
  nsCOMPtr<nsISupports> context = loadInfo->GetLoadingContext();
  nsContentPolicyType contentType = loadInfo->InternalContentPolicyType();
  CHECK_PRINCIPAL_AND_DATA(ShouldLoad);
  if (policyService) {
    CHECK_CONTENT_POLICY_WITH_SERVICE(ShouldLoad, policyService);
  }
  CHECK_CONTENT_POLICY(ShouldLoad);
}

/**
 * Alias for calling ShouldProcess on the content policy service.
 */
inline nsresult NS_CheckContentProcessPolicy(
    nsIURI* contentLocation, nsILoadInfo* loadInfo, const nsACString& mimeType,
    int16_t* decision, nsIContentPolicy* policyService = nullptr) {
  nsIPrincipal* loadingPrincipal = loadInfo->LoadingPrincipal();
  nsCOMPtr<nsISupports> context = loadInfo->GetLoadingContext();
  nsContentPolicyType contentType = loadInfo->InternalContentPolicyType();
  CHECK_PRINCIPAL_AND_DATA(ShouldProcess);
  if (policyService) {
    CHECK_CONTENT_POLICY_WITH_SERVICE(ShouldProcess, policyService);
  }
  CHECK_CONTENT_POLICY(ShouldProcess);
}

#undef CHECK_CONTENT_POLICY
#undef CHECK_CONTENT_POLICY_WITH_SERVICE

/**
 * Helper function to get an nsIDocShell given a context.
 * If the context is a document or window, the corresponding docshell will be
 * returned.
 * If the context is a non-document DOM node, the docshell of its ownerDocument
 * will be returned.
 *
 * @param aContext the context to find a docshell for (can be null)
 *
 * @return a WEAK pointer to the docshell, or nullptr if it could
 *     not be obtained
 *
 * @note  As of this writing, calls to nsIContentPolicy::Should{Load,Process}
 * for TYPE_DOCUMENT and TYPE_SUBDOCUMENT pass in an aContext that either
 * points to the frameElement of the window the load is happening in
 * (in which case NS_CP_GetDocShellFromContext will return the parent of the
 * docshell the load is happening in), or points to the window the load is
 * happening in (in which case NS_CP_GetDocShellFromContext will return
 * the docshell the load is happening in).  It's up to callers to QI aContext
 * and handle things accordingly if they want the docshell the load is
 * happening in.  These are somewhat odd semantics, and bug 466687 has been
 * filed to consider improving them.
 */
inline nsIDocShell* NS_CP_GetDocShellFromContext(nsISupports* aContext) {
  if (!aContext) {
    return nullptr;
  }

  nsCOMPtr<nsPIDOMWindowOuter> window = do_QueryInterface(aContext);

  if (!window) {
    // Our context might be a document.
    nsCOMPtr<mozilla::dom::Document> doc = do_QueryInterface(aContext);
    if (!doc) {
      // we were not a document after all, get our ownerDocument,
      // hopefully
      nsCOMPtr<nsIContent> content = do_QueryInterface(aContext);
      if (content) {
        doc = content->OwnerDoc();
      }
    }

    if (doc) {
      if (doc->GetDisplayDocument()) {
        doc = doc->GetDisplayDocument();
      }

      window = doc->GetWindow();
    }
  }

  if (!window) {
    return nullptr;
  }

  return window->GetDocShell();
}

#endif /* __nsContentPolicyUtils_h__ */