netwerk/protocol/data/nsDataChannel.cpp

   1 /* -*- Mode: C++; tab-width: 2; 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 // data implementation
   7
   8 #include "nsDataChannel.h"
   9
  10 #include "mozilla/Base64.h"
  11 #include "mozilla/dom/MimeType.h"
  12 #include "nsDataHandler.h"
  13 #include "nsIInputStream.h"
  14 #include "nsEscape.h"
  15 #include "nsStringStream.h"
  16 #include "nsIObserverService.h"
  17 #include "mozilla/dom/ContentParent.h"
  18
  19 using namespace mozilla;
  20
  21 /**
  22  * Helper for performing a fallible unescape.
  23  *
  24  * @param aStr The string to unescape.
  25  * @param aBuffer Buffer to unescape into if necessary.
  26  * @param rv Out: nsresult indicating success or failure of unescaping.
  27  * @return Reference to the string containing the unescaped data.
  28  */
  29 const nsACString& Unescape(const nsACString& aStr, nsACString& aBuffer,
  30                            nsresult* rv) {
  31   MOZ_ASSERT(rv);
  32
  33   bool appended = false;
  34   *rv = NS_UnescapeURL(aStr.Data(), aStr.Length(), /* aFlags = */ 0, aBuffer,
  35                        appended, mozilla::fallible);
  36   if (NS_FAILED(*rv) || !appended) {
  37     return aStr;
  38   }
  39
  40   return aBuffer;
  41 }
  42
  43 nsresult nsDataChannel::OpenContentStream(bool async, nsIInputStream** result,
  44                                           nsIChannel** channel) {
  45   NS_ENSURE_TRUE(URI(), NS_ERROR_NOT_INITIALIZED);
  46
  47   nsresult rv;
  48
  49   // In order to avoid potentially building up a new path including the
  50   // ref portion of the URI, which we don't care about, we clone a version
  51   // of the URI that does not have a ref and in most cases should share
  52   // string buffers with the original URI.
  53   nsCOMPtr<nsIURI> uri;
  54   rv = NS_GetURIWithoutRef(URI(), getter_AddRefs(uri));
  55   if (NS_FAILED(rv)) return rv;
  56
  57   nsAutoCString path;
  58   rv = uri->GetPathQueryRef(path);
  59   if (NS_FAILED(rv)) return rv;
  60
  61   nsCString contentType, contentCharset;
  62   nsDependentCSubstring dataRange;
  63   RefPtr<CMimeType> fullMimeType;
  64   bool lBase64;
  65   rv = nsDataHandler::ParsePathWithoutRef(path, contentType, &contentCharset,
  66                                           lBase64, &dataRange, &fullMimeType);
  67   if (NS_FAILED(rv)) return rv;
  68
  69   // This will avoid a copy if nothing needs to be unescaped.
  70   nsAutoCString unescapedBuffer;
  71   const nsACString& data = Unescape(dataRange, unescapedBuffer, &rv);
  72   if (NS_FAILED(rv)) {
  73     return rv;
  74   }
  75
  76   if (lBase64 && &data == &unescapedBuffer) {
  77     // Don't allow spaces in base64-encoded content. This is only
  78     // relevant for escaped spaces; other spaces are stripped in
  79     // NewURI. We know there were no escaped spaces if the data buffer
  80     // wasn't used in |Unescape|.
  81     unescapedBuffer.StripWhitespace();
  82   }
  83
  84   nsCOMPtr<nsIInputStream> bufInStream;
  85   uint32_t contentLen;
  86   if (lBase64) {
  87     nsAutoCString decodedData;
  88     rv = Base64Decode(data, decodedData);
  89     if (NS_FAILED(rv)) {
  90       // Returning this error code instead of what Base64Decode returns
  91       // (NS_ERROR_ILLEGAL_VALUE) will prevent rendering of redirect response
  92       // content by HTTP channels.  It's also more logical error to return.
  93       // Here we know the URL is actually corrupted.
  94       return NS_ERROR_MALFORMED_URI;
  95     }
  96
  97     contentLen = decodedData.Length();
  98     rv = NS_NewCStringInputStream(getter_AddRefs(bufInStream), decodedData);
  99   } else {
 100     contentLen = data.Length();
 101     rv = NS_NewCStringInputStream(getter_AddRefs(bufInStream), data);
 102   }
 103
 104   if (NS_FAILED(rv)) return rv;
 105
 106   SetContentType(contentType);
 107   SetContentCharset(contentCharset);
 108   SetFullMimeType(std::move(fullMimeType));
 109   mContentLength = contentLen;
 110
 111   // notify "data-channel-opened" observers
 112   MaybeSendDataChannelOpenNotification();
 113
 114   bufInStream.forget(result);
 115
 116   return NS_OK;
 117 }
 118
 119 nsresult nsDataChannel::MaybeSendDataChannelOpenNotification() {
 120   nsCOMPtr<nsIObserverService> obsService = services::GetObserverService();
 121   if (!obsService) {
 122     return NS_OK;
 123   }
 124
 125   nsCOMPtr<nsILoadInfo> loadInfo;
 126   nsresult rv = GetLoadInfo(getter_AddRefs(loadInfo));
 127   if (NS_FAILED(rv)) {
 128     return rv;
 129   }
 130
 131   bool isTopLevel;
 132   rv = loadInfo->GetIsTopLevelLoad(&isTopLevel);
 133   if (NS_FAILED(rv)) {
 134     return rv;
 135   }
 136
 137   uint64_t browsingContextID;
 138   rv = loadInfo->GetBrowsingContextID(&browsingContextID);
 139   if (NS_FAILED(rv)) {
 140     return rv;
 141   }
 142
 143   if ((browsingContextID != 0 && isTopLevel) ||
 144       !loadInfo->TriggeringPrincipal()->IsSystemPrincipal()) {
 145     obsService->NotifyObservers(static_cast<nsIChannel*>(this),
 146                                 "data-channel-opened", nullptr);
 147   }
 148   return NS_OK;
 149 }