dom/security/SecFetch.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "SecFetch.h"
   8 #include "nsIHttpChannel.h"
   9 #include "nsContentUtils.h"
  10 #include "nsIRedirectHistoryEntry.h"
  11 #include "nsIReferrerInfo.h"
  12 #include "mozIThirdPartyUtil.h"
  13 #include "nsMixedContentBlocker.h"
  14 #include "nsNetUtil.h"
  15 #include "mozilla/BasePrincipal.h"
  16 #include "mozilla/StaticPrefs_dom.h"
  17
  18 // Helper function which maps an internal content policy type
  19 // to the corresponding destination for the context of SecFetch.
  20 nsCString MapInternalContentPolicyTypeToDest(nsContentPolicyType aType) {
  21   switch (aType) {
  22     case nsIContentPolicy::TYPE_OTHER:
  23       return "empty"_ns;
  24     case nsIContentPolicy::TYPE_INTERNAL_SCRIPT:
  25     case nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD:
  26     case nsIContentPolicy::TYPE_INTERNAL_MODULE:
  27     case nsIContentPolicy::TYPE_INTERNAL_MODULE_PRELOAD:
  28     case nsIContentPolicy::TYPE_INTERNAL_WORKER_IMPORT_SCRIPTS:
  29     case nsIContentPolicy::TYPE_INTERNAL_CHROMEUTILS_COMPILED_SCRIPT:
  30     case nsIContentPolicy::TYPE_INTERNAL_FRAME_MESSAGEMANAGER_SCRIPT:
  31     case nsIContentPolicy::TYPE_SCRIPT:
  32       return "script"_ns;
  33     case nsIContentPolicy::TYPE_INTERNAL_WORKER:
  34       return "worker"_ns;
  35     case nsIContentPolicy::TYPE_INTERNAL_SHARED_WORKER:
  36       return "sharedworker"_ns;
  37     case nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER:
  38       return "serviceworker"_ns;
  39     case nsIContentPolicy::TYPE_INTERNAL_AUDIOWORKLET:
  40       return "audioworklet"_ns;
  41     case nsIContentPolicy::TYPE_INTERNAL_PAINTWORKLET:
  42       return "paintworklet"_ns;
  43     case nsIContentPolicy::TYPE_IMAGESET:
  44     case nsIContentPolicy::TYPE_INTERNAL_IMAGE:
  45     case nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD:
  46     case nsIContentPolicy::TYPE_INTERNAL_IMAGE_FAVICON:
  47     case nsIContentPolicy::TYPE_IMAGE:
  48       return "image"_ns;
  49     case nsIContentPolicy::TYPE_STYLESHEET:
  50     case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET:
  51     case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD:
  52       return "style"_ns;
  53     case nsIContentPolicy::TYPE_OBJECT:
  54     case nsIContentPolicy::TYPE_INTERNAL_OBJECT:
  55       return "object"_ns;
  56     case nsIContentPolicy::TYPE_INTERNAL_EMBED:
  57       return "embed"_ns;
  58     case nsIContentPolicy::TYPE_DOCUMENT:
  59       return "document"_ns;
  60     case nsIContentPolicy::TYPE_SUBDOCUMENT:
  61     case nsIContentPolicy::TYPE_INTERNAL_IFRAME:
  62       return "iframe"_ns;
  63     case nsIContentPolicy::TYPE_INTERNAL_FRAME:
  64       return "frame"_ns;
  65     case nsIContentPolicy::TYPE_PING:
  66       return "empty"_ns;
  67     case nsIContentPolicy::TYPE_XMLHTTPREQUEST:
  68     case nsIContentPolicy::TYPE_INTERNAL_XMLHTTPREQUEST:
  69       return "empty"_ns;
  70     case nsIContentPolicy::TYPE_INTERNAL_EVENTSOURCE:
  71       return "empty"_ns;
  72     case nsIContentPolicy::TYPE_OBJECT_SUBREQUEST:
  73       return "empty"_ns;
  74     case nsIContentPolicy::TYPE_DTD:
  75     case nsIContentPolicy::TYPE_INTERNAL_DTD:
  76     case nsIContentPolicy::TYPE_INTERNAL_FORCE_ALLOWED_DTD:
  77       return "empty"_ns;
  78     case nsIContentPolicy::TYPE_FONT:
  79     case nsIContentPolicy::TYPE_INTERNAL_FONT_PRELOAD:
  80     case nsIContentPolicy::TYPE_UA_FONT:
  81       return "font"_ns;
  82     case nsIContentPolicy::TYPE_MEDIA:
  83       return "empty"_ns;
  84     case nsIContentPolicy::TYPE_INTERNAL_AUDIO:
  85       return "audio"_ns;
  86     case nsIContentPolicy::TYPE_INTERNAL_VIDEO:
  87       return "video"_ns;
  88     case nsIContentPolicy::TYPE_INTERNAL_TRACK:
  89       return "track"_ns;
  90     case nsIContentPolicy::TYPE_WEBSOCKET:
  91       return "websocket"_ns;
  92     case nsIContentPolicy::TYPE_CSP_REPORT:
  93       return "report"_ns;
  94     case nsIContentPolicy::TYPE_XSLT:
  95       return "xslt"_ns;
  96     case nsIContentPolicy::TYPE_BEACON:
  97       return "empty"_ns;
  98     case nsIContentPolicy::TYPE_FETCH:
  99     case nsIContentPolicy::TYPE_INTERNAL_FETCH_PRELOAD:
 100       return "empty"_ns;
 101     case nsIContentPolicy::TYPE_WEB_MANIFEST:
 102       return "manifest"_ns;
 103     case nsIContentPolicy::TYPE_SAVEAS_DOWNLOAD:
 104       return "empty"_ns;
 105     case nsIContentPolicy::TYPE_SPECULATIVE:
 106       return "empty"_ns;
 107     case nsIContentPolicy::TYPE_PROXIED_WEBRTC_MEDIA:
 108       return "empty"_ns;
 109     case nsIContentPolicy::TYPE_WEB_IDENTITY:
 110       return "webidentity"_ns;
 111     case nsIContentPolicy::TYPE_INVALID:
 112       break;
 113       // Do not add default: so that compilers can catch the missing case.
 114   }
 115
 116   MOZ_CRASH("Unhandled nsContentPolicyType value");
 117 }
 118
 119 // Helper function to determine if a ExpandedPrincipal is of the same-origin as
 120 // a URI in the sec-fetch context.
 121 void IsExpandedPrincipalSameOrigin(
 122     nsCOMPtr<nsIExpandedPrincipal> aExpandedPrincipal, nsIURI* aURI,
 123     bool* aRes) {
 124   *aRes = false;
 125   for (const auto& principal : aExpandedPrincipal->AllowList()) {
 126     // Ignore extension principals to continue treating
 127     // "moz-extension:"-requests as not "same-origin".
 128     if (!mozilla::BasePrincipal::Cast(principal)->AddonPolicy()) {
 129       // A ExpandedPrincipal usually has at most one ContentPrincipal, so we can
 130       // check IsSameOrigin on it here and return early.
 131       mozilla::BasePrincipal::Cast(principal)->IsSameOrigin(aURI, aRes);
 132       return;
 133     }
 134   }
 135 }
 136
 137 // Helper function to determine whether a request (including involved
 138 // redirects) is same-origin in the context of SecFetch.
 139 bool IsSameOrigin(nsIHttpChannel* aHTTPChannel) {
 140   nsCOMPtr<nsIURI> channelURI;
 141   NS_GetFinalChannelURI(aHTTPChannel, getter_AddRefs(channelURI));
 142
 143   nsCOMPtr<nsILoadInfo> loadInfo = aHTTPChannel->LoadInfo();
 144
 145   if (mozilla::BasePrincipal::Cast(loadInfo->TriggeringPrincipal())
 146           ->AddonPolicy()) {
 147     // If an extension triggered the load that has access to the URI then the
 148     // load is considered as same-origin.
 149     return mozilla::BasePrincipal::Cast(loadInfo->TriggeringPrincipal())
 150         ->AddonAllowsLoad(channelURI);
 151   }
 152
 153   bool isSameOrigin = false;
 154   if (nsContentUtils::IsExpandedPrincipal(loadInfo->TriggeringPrincipal())) {
 155     nsCOMPtr<nsIExpandedPrincipal> ep =
 156         do_QueryInterface(loadInfo->TriggeringPrincipal());
 157     IsExpandedPrincipalSameOrigin(ep, channelURI, &isSameOrigin);
 158   } else {
 159     isSameOrigin = loadInfo->TriggeringPrincipal()->IsSameOrigin(channelURI);
 160   }
 161
 162   // if the initial request is not same-origin, we can return here
 163   // because we already know it's not a same-origin request
 164   if (!isSameOrigin) {
 165     return false;
 166   }
 167
 168   // let's further check all the hoops in the redirectChain to
 169   // ensure all involved redirects are same-origin
 170   nsCOMPtr<nsIPrincipal> redirectPrincipal;
 171   for (nsIRedirectHistoryEntry* entry : loadInfo->RedirectChain()) {
 172     entry->GetPrincipal(getter_AddRefs(redirectPrincipal));
 173     if (redirectPrincipal && !redirectPrincipal->IsSameOrigin(channelURI)) {
 174       return false;
 175     }
 176   }
 177
 178   // must be a same-origin request
 179   return true;
 180 }
 181
 182 // Helper function to determine whether a request (including involved
 183 // redirects) is same-site in the context of SecFetch.
 184 bool IsSameSite(nsIChannel* aHTTPChannel) {
 185   nsCOMPtr<mozIThirdPartyUtil> thirdPartyUtil =
 186       do_GetService(THIRDPARTYUTIL_CONTRACTID);
 187   if (!thirdPartyUtil) {
 188     return false;
 189   }
 190
 191   nsAutoCString hostDomain;
 192   nsCOMPtr<nsILoadInfo> loadInfo = aHTTPChannel->LoadInfo();
 193   nsresult rv = loadInfo->TriggeringPrincipal()->GetBaseDomain(hostDomain);
 194   mozilla::Unused << NS_WARN_IF(NS_FAILED(rv));
 195
 196   nsAutoCString channelDomain;
 197   nsCOMPtr<nsIURI> channelURI;
 198   NS_GetFinalChannelURI(aHTTPChannel, getter_AddRefs(channelURI));
 199   rv = thirdPartyUtil->GetBaseDomain(channelURI, channelDomain);
 200   mozilla::Unused << NS_WARN_IF(NS_FAILED(rv));
 201
 202   // if the initial request is not same-site, or not https, we can
 203   // return here because we already know it's not a same-site request
 204   if (!hostDomain.Equals(channelDomain) ||
 205       (!loadInfo->TriggeringPrincipal()->SchemeIs("https") &&
 206        !nsMixedContentBlocker::IsPotentiallyTrustworthyLoopbackHost(
 207            hostDomain))) {
 208     return false;
 209   }
 210
 211   // let's further check all the hoops in the redirectChain to
 212   // ensure all involved redirects are same-site and https
 213   nsCOMPtr<nsIPrincipal> redirectPrincipal;
 214   for (nsIRedirectHistoryEntry* entry : loadInfo->RedirectChain()) {
 215     entry->GetPrincipal(getter_AddRefs(redirectPrincipal));
 216     if (redirectPrincipal) {
 217       redirectPrincipal->GetBaseDomain(hostDomain);
 218       if (!hostDomain.Equals(channelDomain) ||
 219           !redirectPrincipal->SchemeIs("https")) {
 220         return false;
 221       }
 222     }
 223   }
 224
 225   // must be a same-site request
 226   return true;
 227 }
 228
 229 // Helper function to determine whether a request was triggered
 230 // by the end user in the context of SecFetch.
 231 bool IsUserTriggeredForSecFetchSite(nsIHttpChannel* aHTTPChannel) {
 232   /*
 233    * The goal is to distinguish between "webby" navigations that are controlled
 234    * by a given website (e.g. links, the window.location setter,form
 235    * submissions, etc.), and those that are not (e.g. user interaction with a
 236    * user agent’s address bar, bookmarks, etc).
 237    */
 238   nsCOMPtr<nsILoadInfo> loadInfo = aHTTPChannel->LoadInfo();
 239   ExtContentPolicyType contentType = loadInfo->GetExternalContentPolicyType();
 240
 241   // A request issued by the browser is always user initiated.
 242   if (loadInfo->TriggeringPrincipal()->IsSystemPrincipal() &&
 243       contentType == ExtContentPolicy::TYPE_OTHER) {
 244     return true;
 245   }
 246
 247   // only requests wich result in type "document" are subject to
 248   // user initiated actions in the context of SecFetch.
 249   if (contentType != ExtContentPolicy::TYPE_DOCUMENT &&
 250       contentType != ExtContentPolicy::TYPE_SUBDOCUMENT) {
 251     return false;
 252   }
 253
 254   // The load is considered user triggered if it was triggered by an external
 255   // application.
 256   if (loadInfo->GetLoadTriggeredFromExternal()) {
 257     return true;
 258   }
 259
 260   // sec-fetch-site can only be user triggered if the load was user triggered.
 261   if (!loadInfo->GetHasValidUserGestureActivation()) {
 262     return false;
 263   }
 264
 265   // We can assert that the navigation must be "webby" if the load was triggered
 266   // by a meta refresh. See also Bug 1647128.
 267   if (loadInfo->GetIsMetaRefresh()) {
 268     return false;
 269   }
 270
 271   // All web requests have a valid "original" referrer set in the
 272   // ReferrerInfo which we can use to determine whether a request
 273   // was triggered by a user or not.
 274   nsCOMPtr<nsIReferrerInfo> referrerInfo = aHTTPChannel->GetReferrerInfo();
 275   if (referrerInfo) {
 276     nsCOMPtr<nsIURI> originalReferrer;
 277     referrerInfo->GetOriginalReferrer(getter_AddRefs(originalReferrer));
 278     if (originalReferrer) {
 279       return false;
 280     }
 281   }
 282
 283   return true;
 284 }
 285
 286 void mozilla::dom::SecFetch::AddSecFetchDest(nsIHttpChannel* aHTTPChannel) {
 287   nsCOMPtr<nsILoadInfo> loadInfo = aHTTPChannel->LoadInfo();
 288   nsContentPolicyType contentType = loadInfo->InternalContentPolicyType();
 289   nsCString dest = MapInternalContentPolicyTypeToDest(contentType);
 290
 291   nsresult rv =
 292       aHTTPChannel->SetRequestHeader("Sec-Fetch-Dest"_ns, dest, false);
 293   mozilla::Unused << NS_WARN_IF(NS_FAILED(rv));
 294 }
 295
 296 void mozilla::dom::SecFetch::AddSecFetchMode(nsIHttpChannel* aHTTPChannel) {
 297   nsAutoCString mode("no-cors");
 298
 299   nsCOMPtr<nsILoadInfo> loadInfo = aHTTPChannel->LoadInfo();
 300   uint32_t securityMode = loadInfo->GetSecurityMode();
 301   ExtContentPolicyType externalType = loadInfo->GetExternalContentPolicyType();
 302
 303   if (securityMode ==
 304           nsILoadInfo::SEC_REQUIRE_SAME_ORIGIN_INHERITS_SEC_CONTEXT ||
 305       securityMode == nsILoadInfo::SEC_REQUIRE_SAME_ORIGIN_DATA_IS_BLOCKED) {
 306     mode = "same-origin"_ns;
 307   } else if (securityMode ==
 308              nsILoadInfo::SEC_REQUIRE_CORS_INHERITS_SEC_CONTEXT) {
 309     mode = "cors"_ns;
 310   } else {
 311     // If it's not one of the security modes above, then we ensure it's
 312     // at least one of the others defined in nsILoadInfo
 313     MOZ_ASSERT(
 314         securityMode ==
 315                 nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_INHERITS_SEC_CONTEXT ||
 316             securityMode ==
 317                 nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
 318         "unhandled security mode");
 319   }
 320
 321   if (externalType == ExtContentPolicy::TYPE_DOCUMENT ||
 322       externalType == ExtContentPolicy::TYPE_SUBDOCUMENT ||
 323       externalType == ExtContentPolicy::TYPE_OBJECT) {
 324     mode = "navigate"_ns;
 325   } else if (externalType == ExtContentPolicy::TYPE_WEBSOCKET) {
 326     mode = "websocket"_ns;
 327   }
 328
 329   nsresult rv =
 330       aHTTPChannel->SetRequestHeader("Sec-Fetch-Mode"_ns, mode, false);
 331   mozilla::Unused << NS_WARN_IF(NS_FAILED(rv));
 332 }
 333
 334 void mozilla::dom::SecFetch::AddSecFetchSite(nsIHttpChannel* aHTTPChannel) {
 335   nsAutoCString site("same-origin");
 336
 337   bool isSameOrigin = IsSameOrigin(aHTTPChannel);
 338   if (!isSameOrigin) {
 339     bool isSameSite = IsSameSite(aHTTPChannel);
 340     if (isSameSite) {
 341       site = "same-site"_ns;
 342     } else {
 343       site = "cross-site"_ns;
 344     }
 345   }
 346
 347   if (IsUserTriggeredForSecFetchSite(aHTTPChannel)) {
 348     site = "none"_ns;
 349   }
 350
 351   nsresult rv =
 352       aHTTPChannel->SetRequestHeader("Sec-Fetch-Site"_ns, site, false);
 353   mozilla::Unused << NS_WARN_IF(NS_FAILED(rv));
 354 }
 355
 356 void mozilla::dom::SecFetch::AddSecFetchUser(nsIHttpChannel* aHTTPChannel) {
 357   nsCOMPtr<nsILoadInfo> loadInfo = aHTTPChannel->LoadInfo();
 358   ExtContentPolicyType externalType = loadInfo->GetExternalContentPolicyType();
 359
 360   // sec-fetch-user only applies to loads of type document or subdocument
 361   if (externalType != ExtContentPolicy::TYPE_DOCUMENT &&
 362       externalType != ExtContentPolicy::TYPE_SUBDOCUMENT) {
 363     return;
 364   }
 365
 366   // sec-fetch-user only applies if the request is user triggered.
 367   // requests triggered by an external application are considerd user triggered.
 368   if (!loadInfo->GetLoadTriggeredFromExternal() &&
 369       !loadInfo->GetHasValidUserGestureActivation()) {
 370     return;
 371   }
 372
 373   nsAutoCString user("?1");
 374   nsresult rv =
 375       aHTTPChannel->SetRequestHeader("Sec-Fetch-User"_ns, user, false);
 376   mozilla::Unused << NS_WARN_IF(NS_FAILED(rv));
 377 }
 378
 379 void mozilla::dom::SecFetch::AddSecFetchHeader(nsIHttpChannel* aHTTPChannel) {
 380   // if sec-fetch-* is prefed off, then there is nothing to do
 381   if (!StaticPrefs::dom_security_secFetch_enabled()) {
 382     return;
 383   }
 384
 385   nsCOMPtr<nsIURI> uri;
 386   nsresult rv = aHTTPChannel->GetURI(getter_AddRefs(uri));
 387   if (NS_WARN_IF(NS_FAILED(rv))) {
 388     return;
 389   }
 390
 391   // if we are not dealing with a potentially trustworthy URL, then
 392   // there is nothing to do here
 393   if (!nsMixedContentBlocker::IsPotentiallyTrustworthyOrigin(uri)) {
 394     return;
 395   }
 396
 397   AddSecFetchDest(aHTTPChannel);
 398   AddSecFetchMode(aHTTPChannel);
 399   AddSecFetchSite(aHTTPChannel);
 400   AddSecFetchUser(aHTTPChannel);
 401 }