parser/html/nsParserUtils.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsParserUtils.h"
   7 #include "mozilla/NullPrincipal.h"
   8 #include "mozilla/UniquePtr.h"
   9 #include "mozilla/dom/DocumentFragment.h"
  10 #include "mozilla/dom/Element.h"
  11 #include "mozilla/dom/ScriptLoader.h"
  12 #include "nsAttrName.h"
  13 #include "nsCOMPtr.h"
  14 #include "nsContentUtils.h"
  15 #include "nsEscape.h"
  16 #include "nsHTMLParts.h"
  17 #include "nsHtml5Module.h"
  18 #include "nsIContent.h"
  19 #include "nsIContentSink.h"
  20 #include "nsIDTD.h"
  21 #include "mozilla/dom/Document.h"
  22 #include "nsIDocumentEncoder.h"
  23 #include "nsIFragmentContentSink.h"
  24 #include "nsIParser.h"
  25 #include "nsNetCID.h"
  26 #include "nsNetUtil.h"
  27 #include "nsString.h"
  28 #include "nsTreeSanitizer.h"
  29 #include "nsXPCOM.h"
  30
  31 #define XHTML_DIV_TAG u"div xmlns=\"http://www.w3.org/1999/xhtml\""
  32
  33 using namespace mozilla::dom;
  34
  35 NS_IMPL_ISUPPORTS(nsParserUtils, nsIParserUtils)
  36
  37 NS_IMETHODIMP
  38 nsParserUtils::ConvertToPlainText(const nsAString& aFromStr, uint32_t aFlags,
  39                                   uint32_t aWrapCol, nsAString& aToStr) {
  40   return nsContentUtils::ConvertToPlainText(aFromStr, aToStr, aFlags, aWrapCol);
  41 }
  42
  43 template <typename Callable>
  44 static nsresult SanitizeWith(const nsAString& aInput, nsAString& aOutput,
  45                              Callable aDoSanitize) {
  46   RefPtr<Document> document = nsContentUtils::CreateInertHTMLDocument(nullptr);
  47   if (!document) {
  48     return NS_ERROR_FAILURE;
  49   }
  50
  51   nsresult rv = nsContentUtils::ParseDocumentHTML(aInput, document, false);
  52   NS_ENSURE_SUCCESS(rv, rv);
  53
  54   aDoSanitize(document.get());
  55
  56   nsCOMPtr<nsIDocumentEncoder> encoder = do_createDocumentEncoder("text/html");
  57   encoder->NativeInit(document, u"text/html"_ns,
  58                       nsIDocumentEncoder::OutputDontRewriteEncodingDeclaration |
  59                           nsIDocumentEncoder::OutputNoScriptContent |
  60                           nsIDocumentEncoder::OutputEncodeBasicEntities |
  61                           nsIDocumentEncoder::OutputLFLineBreak |
  62                           nsIDocumentEncoder::OutputRaw);
  63   return encoder->EncodeToString(aOutput);
  64 }
  65
  66 NS_IMETHODIMP
  67 nsParserUtils::Sanitize(const nsAString& aFromStr, uint32_t aFlags,
  68                         nsAString& aToStr) {
  69   return SanitizeWith(aFromStr, aToStr, [&](Document* aDocument) {
  70     nsTreeSanitizer sanitizer(aFlags);
  71     sanitizer.Sanitize(aDocument);
  72   });
  73 }
  74
  75 NS_IMETHODIMP
  76 nsParserUtils::RemoveConditionalCSS(const nsAString& aFromStr,
  77                                     nsAString& aToStr) {
  78   return SanitizeWith(aFromStr, aToStr, [](Document* aDocument) {
  79     nsTreeSanitizer::RemoveConditionalCSSFromSubtree(aDocument);
  80   });
  81 }
  82
  83 NS_IMETHODIMP
  84 nsParserUtils::ParseFragment(const nsAString& aFragment, uint32_t aFlags,
  85                              bool aIsXML, nsIURI* aBaseURI,
  86                              Element* aContextElement,
  87                              DocumentFragment** aReturn) {
  88   NS_ENSURE_ARG(aContextElement);
  89   *aReturn = nullptr;
  90
  91   RefPtr<Document> document = aContextElement->OwnerDoc();
  92
  93   nsAutoScriptBlockerSuppressNodeRemoved autoBlocker;
  94
  95   // stop scripts
  96   RefPtr<ScriptLoader> loader = document->ScriptLoader();
  97   bool scripts_enabled = loader->GetEnabled();
  98   if (scripts_enabled) {
  99     loader->SetEnabled(false);
 100   }
 101
 102   // Wrap things in a div or body for parsing, but it won't show up in
 103   // the fragment.
 104   nsresult rv = NS_OK;
 105   AutoTArray<nsString, 2> tagStack;
 106   RefPtr<DocumentFragment> fragment;
 107   if (aIsXML) {
 108     // XHTML
 109     tagStack.AppendElement(nsLiteralString(XHTML_DIV_TAG));
 110     rv = nsContentUtils::ParseFragmentXML(aFragment, document, tagStack, true,
 111                                           aFlags, getter_AddRefs(fragment));
 112   } else {
 113     fragment = new (document->NodeInfoManager())
 114         DocumentFragment(document->NodeInfoManager());
 115     rv = nsContentUtils::ParseFragmentHTML(aFragment, fragment, nsGkAtoms::body,
 116                                            kNameSpaceID_XHTML, false, true,
 117                                            aFlags);
 118   }
 119
 120   if (scripts_enabled) {
 121     loader->SetEnabled(true);
 122   }
 123
 124   fragment.forget(aReturn);
 125   return rv;
 126 }