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/* -*- 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 "nsNetUtil.h"
#include "nsSimpleURI.h"
#include "nsUnicharUtils.h"
#include "mozilla/dom/MimeType.h"
#include "mozilla/StaticPrefs_network.h"
#include "mozilla/Try.h"
#include "DefaultURI.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;
// use DefaultURI to check for validity when we have possible hostnames
// since nsSimpleURI doesn't know about hostnames
auto pos = aSpec.Find("data:");
if (pos != kNotFound) {
nsDependentCSubstring rest(aSpec, pos + sizeof("data:") - 1, -1);
if (StringBeginsWith(rest, "//"_ns)) {
nsCOMPtr<nsIURI> uriWithHost;
rv = NS_MutateURI(new mozilla::net::DefaultURI::Mutator())
.SetSpec(aSpec)
.Finalize(uriWithHost);
NS_ENSURE_SUCCESS(rv, 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;
}
namespace {
bool TrimSpacesAndBase64(nsACString& aMimeType) {
const char* beg = aMimeType.BeginReading();
const char* end = aMimeType.EndReading();
// trim leading and trailing spaces
while (beg < end && NS_IsHTTPWhitespace(*beg)) {
++beg;
}
if (beg == end) {
aMimeType.Truncate();
return false;
}
while (end > beg && NS_IsHTTPWhitespace(*(end - 1))) {
--end;
}
if (beg == end) {
aMimeType.Truncate();
return false;
}
// trim trailing `; base64` (if any) and remember it
const char* pos = end - 1;
bool foundBase64 = false;
if (pos > beg && *pos == '4' && --pos > beg && *pos == '6' && --pos > beg &&
ToLowerCaseASCII(*pos) == 'e' && --pos > beg &&
ToLowerCaseASCII(*pos) == 's' && --pos > beg &&
ToLowerCaseASCII(*pos) == 'a' && --pos > beg &&
ToLowerCaseASCII(*pos) == 'b') {
while (--pos > beg && NS_IsHTTPWhitespace(*pos)) {
}
if (pos >= beg && *pos == ';') {
end = pos;
foundBase64 = true;
}
}
// actually trim off the spaces and trailing base64, returning if we found it.
const char* s = aMimeType.BeginReading();
aMimeType.Assign(Substring(aMimeType, beg - s, end - s));
return foundBase64;
}
} // namespace
nsresult nsDataHandler::ParsePathWithoutRef(const nsACString& aPath,
nsCString& aContentType,
nsCString* aContentCharset,
bool& aIsBase64,
nsDependentCSubstring* aDataBuffer,
nsCString* aMimeType) {
static constexpr auto kCharset = "charset"_ns;
// It also returns the full mimeType in aMimeType so fetch/XHR may access it
// for content-length headers. The contentType and charset parameters retain
// our legacy behavior, as much Gecko code generally expects GetContentType
// to yield only the MimeType's essence, not its full value with parameters.
aIsBase64 = false;
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;
}
// "Let mimeType be the result of collecting a sequence of code points that
// are not equal to U+002C (,), given position."
nsCString mimeType(Substring(aPath, 0, commaIdx));
// "Strip leading and trailing ASCII whitespace from mimeType."
// "If mimeType ends with U+003B (;), followed by zero or more U+0020 SPACE,
// followed by an ASCII case-insensitive match for "base64", then ..."
aIsBase64 = TrimSpacesAndBase64(mimeType);
// "If mimeType starts with ";", then prepend "text/plain" to mimeType."
if (mimeType.Length() > 0 && mimeType.CharAt(0) == ';') {
mimeType = "text/plain"_ns + mimeType;
}
// "Let mimeTypeRecord be the result of parsing mimeType."
// This also checks for instances of ;base64 in the middle of the MimeType.
// This is against the current spec, but we're doing it because we have
// historically seen webcompat issues relying on this (see bug 781693).
if (mozilla::UniquePtr<CMimeType> parsed = CMimeType::Parse(mimeType)) {
parsed->GetEssence(aContentType);
if (aContentCharset) {
parsed->GetParameterValue(kCharset, *aContentCharset);
}
if (aMimeType) {
parsed->Serialize(*aMimeType);
}
if (parsed->IsBase64() &&
!StaticPrefs::network_url_strict_data_url_base64_placement()) {
aIsBase64 = true;
}
} else {
// "If mimeTypeRecord is failure, then set mimeTypeRecord to
// text/plain;charset=US-ASCII."
aContentType.AssignLiteral("text/plain");
if (aContentCharset) {
aContentCharset->AssignLiteral("US-ASCII");
}
if (aMimeType) {
aMimeType->AssignLiteral("text/plain;charset=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;
}