1 files changed, 247 insertions, 0 deletions
diff --git a/netwerk/protocol/data/nsDataHandler.cpp b/netwerk/protocol/data/nsDataHandler.cpp
new file mode 100644
index 0000000000..09ba7584a3
--- /dev/null
+++ b/netwerk/protocol/data/nsDataHandler.cpp
@@ -0,0 +1,247 @@
+/* -*- Mode: C++; tab-width: 2; 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/. */
+
+#include "nsDataChannel.h"
+#include "nsDataHandler.h"
+#include "nsNetCID.h"
+#include "nsError.h"
+#include "nsIOService.h"
+#include "DataChannelChild.h"
+#include "nsSimpleURI.h"
+#include "mozilla/dom/MimeType.h"
+#include "mozilla/StaticPrefs_network.h"
+
+using namespace mozilla;
+
+////////////////////////////////////////////////////////////////////////////////
+
+NS_IMPL_ISUPPORTS(nsDataHandler, nsIProtocolHandler, nsISupportsWeakReference)
+
+nsresult nsDataHandler::Create(const nsIID& aIID, void** aResult) {
+  RefPtr<nsDataHandler> ph = new nsDataHandler();
+  return ph->QueryInterface(aIID, aResult);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsIProtocolHandler methods:
+
+NS_IMETHODIMP
+nsDataHandler::GetScheme(nsACString& result) {
+  result.AssignLiteral("data");
+  return NS_OK;
+}
+
+/* static */ nsresult nsDataHandler::CreateNewURI(const nsACString& aSpec,
+                                                  const char* aCharset,
+                                                  nsIURI* aBaseURI,
+                                                  nsIURI** result) {
+  nsCOMPtr<nsIURI> uri;
+  nsAutoCString contentType;
+  bool base64;
+  MOZ_TRY(ParseURI(aSpec, contentType, /* contentCharset = */ nullptr, base64,
+                   /* dataBuffer = */ nullptr));
+
+  // Strip whitespace unless this is text, where whitespace is important
+  // Don't strip escaped whitespace though (bug 391951)
+  nsresult rv;
+  if (base64 || (StaticPrefs::network_url_strip_data_url_whitespace() &&
+                 strncmp(contentType.get(), "text/", 5) != 0 &&
+                 contentType.Find("xml") == kNotFound)) {
+    // it's ascii encoded binary, don't let any spaces in
+    rv = NS_MutateURI(new mozilla::net::nsSimpleURI::Mutator())
+             .Apply(&nsISimpleURIMutator::SetSpecAndFilterWhitespace, aSpec,
+                    nullptr)
+             .Finalize(uri);
+  } else {
+    rv = NS_MutateURI(new mozilla::net::nsSimpleURI::Mutator())
+             .SetSpec(aSpec)
+             .Finalize(uri);
+  }
+
+  if (NS_FAILED(rv)) return rv;
+
+  uri.forget(result);
+  return rv;
+}
+
+NS_IMETHODIMP
+nsDataHandler::NewChannel(nsIURI* uri, nsILoadInfo* aLoadInfo,
+                          nsIChannel** result) {
+  NS_ENSURE_ARG_POINTER(uri);
+  RefPtr<nsDataChannel> channel;
+  if (XRE_IsParentProcess()) {
+    channel = new nsDataChannel(uri);
+  } else {
+    channel = new mozilla::net::DataChannelChild(uri);
+  }
+
+  // set the loadInfo on the new channel
+  nsresult rv = channel->SetLoadInfo(aLoadInfo);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  channel.forget(result);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsDataHandler::AllowPort(int32_t port, const char* scheme, bool* _retval) {
+  // don't override anything.
+  *_retval = false;
+  return NS_OK;
+}
+
+/**
+ * Helper that performs a case insensitive match to find the offset of a given
+ * pattern in a nsACString.
+ * The search is performed starting from the end of the string; if the string
+ * contains more than one match, the rightmost (last) match will be returned.
+ */
+static bool FindOffsetOf(const nsACString& aPattern, const nsACString& aSrc,
+                         nsACString::size_type& aOffset) {
+  nsACString::const_iterator begin, end;
+  aSrc.BeginReading(begin);
+  aSrc.EndReading(end);
+  if (!RFindInReadable(aPattern, begin, end,
+                       nsCaseInsensitiveCStringComparator)) {
+    return false;
+  }
+
+  // FindInReadable updates |begin| and |end| to the match coordinates.
+  aOffset = nsACString::size_type(begin.get() - aSrc.Data());
+  return true;
+}
+
+nsresult nsDataHandler::ParsePathWithoutRef(
+    const nsACString& aPath, nsCString& aContentType,
+    nsCString* aContentCharset, bool& aIsBase64,
+    nsDependentCSubstring* aDataBuffer) {
+  static constexpr auto kBase64 = "base64"_ns;
+  static constexpr auto kCharset = "charset"_ns;
+
+  aIsBase64 = false;
+
+  // First, find the start of the data
+  int32_t commaIdx = aPath.FindChar(',');
+
+  // This is a hack! When creating a URL using the DOM API we want to ignore
+  // if a comma is missing. But if we're actually loading a data: URI, in which
+  // case aContentCharset is not null, then we want to return an error if a
+  // comma is missing.
+  if (aContentCharset && commaIdx == kNotFound) {
+    return NS_ERROR_MALFORMED_URI;
+  }
+  if (commaIdx == 0 || commaIdx == kNotFound) {
+    // Nothing but data.
+    aContentType.AssignLiteral("text/plain");
+    if (aContentCharset) {
+      aContentCharset->AssignLiteral("US-ASCII");
+    }
+  } else {
+    auto mediaType = Substring(aPath, 0, commaIdx);
+
+    // Determine if the data is base64 encoded.
+    nsACString::size_type base64;
+    if (FindOffsetOf(kBase64, mediaType, base64) && base64 > 0) {
+      nsACString::size_type offset = base64 + kBase64.Length();
+      // Per the RFC 2397 grammar, "base64" MUST be at the end of the
+      // non-data part.
+      //
+      // But we also allow it in between parameters so a subsequent ";"
+      // is ok as well (this deals with *broken* data URIs, see bug
+      // 781693 for an example). Anything after "base64" in the non-data
+      // part will be discarded in this case, however.
+      if (offset == mediaType.Length() || mediaType[offset] == ';' ||
+          mediaType[offset] == ' ') {
+        MOZ_DIAGNOSTIC_ASSERT(base64 > 0, "Did someone remove the check?");
+        // Index is on the first character of matched "base64" so we
+        // move to the preceding character
+        base64--;
+        // Skip any preceding spaces, searching for a semicolon
+        while (base64 > 0 && mediaType[base64] == ' ') {
+          base64--;
+        }
+        if (mediaType[base64] == ';') {
+          aIsBase64 = true;
+          // Trim the base64 part off.
+          mediaType.Rebind(aPath, 0, base64);
+        }
+      }
+    }
+
+    // Skip any leading spaces
+    nsACString::size_type startIndex = 0;
+    while (startIndex < mediaType.Length() && mediaType[startIndex] == ' ') {
+      startIndex++;
+    }
+
+    nsAutoCString mediaTypeBuf;
+    // If the mimetype starts with ';' we assume text/plain
+    if (startIndex < mediaType.Length() && mediaType[startIndex] == ';') {
+      mediaTypeBuf.AssignLiteral("text/plain");
+      mediaTypeBuf.Append(mediaType);
+      mediaType.Rebind(mediaTypeBuf, 0, mediaTypeBuf.Length());
+    }
+
+    // Everything else is content type.
+    if (mozilla::UniquePtr<CMimeType> parsed = CMimeType::Parse(mediaType)) {
+      parsed->GetFullType(aContentType);
+      if (aContentCharset) {
+        parsed->GetParameterValue(kCharset, *aContentCharset);
+      }
+    } else {
+      // Mime Type parsing failed
+      aContentType.AssignLiteral("text/plain");
+      if (aContentCharset) {
+        aContentCharset->AssignLiteral("US-ASCII");
+      }
+    }
+  }
+
+  if (aDataBuffer) {
+    aDataBuffer->Rebind(aPath, commaIdx + 1);
+  }
+
+  return NS_OK;
+}
+
+static inline char ToLower(const char c) {
+  if (c >= 'A' && c <= 'Z') {
+    return char(c + ('a' - 'A'));
+  }
+  return c;
+}
+
+nsresult nsDataHandler::ParseURI(const nsACString& spec, nsCString& contentType,
+                                 nsCString* contentCharset, bool& isBase64,
+                                 nsCString* dataBuffer) {
+  static constexpr auto kDataScheme = "data:"_ns;
+
+  // move past "data:"
+  const char* pos = std::search(
+      spec.BeginReading(), spec.EndReading(), kDataScheme.BeginReading(),
+      kDataScheme.EndReading(),
+      [](const char a, const char b) { return ToLower(a) == ToLower(b); });
+  if (pos == spec.EndReading()) {
+    return NS_ERROR_MALFORMED_URI;
+  }
+
+  uint32_t scheme = pos - spec.BeginReading();
+  scheme += kDataScheme.Length();
+
+  // Find the start of the hash ref if present.
+  int32_t hash = spec.FindChar('#', scheme);
+
+  auto pathWithoutRef = Substring(spec, scheme, hash != kNotFound ? hash : -1);
+  nsDependentCSubstring dataRange;
+  nsresult rv = ParsePathWithoutRef(pathWithoutRef, contentType, contentCharset,
+                                    isBase64, &dataRange);
+  if (NS_SUCCEEDED(rv) && dataBuffer) {
+    if (!dataBuffer->Assign(dataRange, mozilla::fallible)) {
+      rv = NS_ERROR_OUT_OF_MEMORY;
+    }
+  }
+
+  return rv;
+}