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 "nsContentCID.h"
  15 #include "nsContentUtils.h"
  16 #include "nsEscape.h"
  17 #include "nsHTMLParts.h"
  18 #include "nsHtml5Module.h"
  19 #include "nsIContent.h"
  20 #include "nsIContentSink.h"
  21 #include "nsIDTD.h"
  22 #include "mozilla/dom/Document.h"
  23 #include "nsIDocumentEncoder.h"
  24 #include "nsIFragmentContentSink.h"
  25 #include "nsIParser.h"
  26 #include "nsNetCID.h"
  27 #include "nsNetUtil.h"
  28 #include "nsString.h"
  29 #include "nsTreeSanitizer.h"
  30 #include "nsXPCOM.h"
  31
  32 #define XHTML_DIV_TAG u"div xmlns=\"http://www.w3.org/1999/xhtml\""
  33
  34 using namespace mozilla::dom;
  35
  36 NS_IMPL_ISUPPORTS(nsParserUtils, nsIParserUtils)
  37
  38 NS_IMETHODIMP
  39 nsParserUtils::ConvertToPlainText(const nsAString& aFromStr, uint32_t aFlags,
  40                                   uint32_t aWrapCol, nsAString& aToStr) {
  41   return nsContentUtils::ConvertToPlainText(aFromStr, aToStr, aFlags, aWrapCol);
  42 }
  43
  44 template <typename Callable>
  45 static nsresult SanitizeWith(const nsAString& aInput, nsAString& aOutput,
  46                              Callable aDoSanitize) {
  47   RefPtr<Document> document = nsContentUtils::CreateInertHTMLDocument(nullptr);
  48   if (!document) {
  49     return NS_ERROR_FAILURE;
  50   }
  51
  52   nsresult rv = nsContentUtils::ParseDocumentHTML(aInput, document, false);
  53   NS_ENSURE_SUCCESS(rv, rv);
  54
  55   aDoSanitize(document.get());
  56
  57   nsCOMPtr<nsIDocumentEncoder> encoder = do_createDocumentEncoder("text/html");
  58   encoder->NativeInit(document, u"text/html"_ns,
  59                       nsIDocumentEncoder::OutputDontRewriteEncodingDeclaration |
  60                           nsIDocumentEncoder::OutputNoScriptContent |
  61                           nsIDocumentEncoder::OutputEncodeBasicEntities |
  62                           nsIDocumentEncoder::OutputLFLineBreak |
  63                           nsIDocumentEncoder::OutputRaw);
  64   return encoder->EncodeToString(aOutput);
  65 }
  66
  67 NS_IMETHODIMP
  68 nsParserUtils::Sanitize(const nsAString& aFromStr, uint32_t aFlags,
  69                         nsAString& aToStr) {
  70   return SanitizeWith(aFromStr, aToStr, [&](Document* aDocument) {
  71     nsTreeSanitizer sanitizer(aFlags);
  72     sanitizer.Sanitize(aDocument);
  73   });
  74 }
  75
  76 NS_IMETHODIMP
  77 nsParserUtils::RemoveConditionalCSS(const nsAString& aFromStr,
  78                                     nsAString& aToStr) {
  79   return SanitizeWith(aFromStr, aToStr, [](Document* aDocument) {
  80     nsTreeSanitizer::RemoveConditionalCSSFromSubtree(aDocument);
  81   });
  82 }
  83
  84 NS_IMETHODIMP
  85 nsParserUtils::ParseFragment(const nsAString& aFragment, uint32_t aFlags,
  86                              bool aIsXML, nsIURI* aBaseURI,
  87                              Element* aContextElement,
  88                              DocumentFragment** aReturn) {
  89   NS_ENSURE_ARG(aContextElement);
  90   *aReturn = nullptr;
  91
  92   RefPtr<Document> document = aContextElement->OwnerDoc();
  93
  94   nsAutoScriptBlockerSuppressNodeRemoved autoBlocker;
  95
  96   // stop scripts
  97   RefPtr<ScriptLoader> loader = document->ScriptLoader();
  98   bool scripts_enabled = loader->GetEnabled();
  99   if (scripts_enabled) {
 100     loader->SetEnabled(false);
 101   }
 102
 103   // Wrap things in a div or body for parsing, but it won't show up in
 104   // the fragment.
 105   nsresult rv = NS_OK;
 106   AutoTArray<nsString, 2> tagStack;
 107   RefPtr<DocumentFragment> fragment;
 108   if (aIsXML) {
 109     // XHTML
 110     tagStack.AppendElement(nsLiteralString(XHTML_DIV_TAG));
 111     rv = nsContentUtils::ParseFragmentXML(aFragment, document, tagStack, true,
 112                                           aFlags, getter_AddRefs(fragment));
 113   } else {
 114     fragment = new (document->NodeInfoManager())
 115         DocumentFragment(document->NodeInfoManager());
 116     rv = nsContentUtils::ParseFragmentHTML(aFragment, fragment, nsGkAtoms::body,
 117                                            kNameSpaceID_XHTML, false, true,
 118                                            aFlags);
 119   }
 120
 121   if (scripts_enabled) {
 122     loader->SetEnabled(true);
 123   }
 124
 125   fragment.forget(aReturn);
 126   return rv;
 127 }