mozilla
/
pjs
зеркало из https://github.com/mozilla/pjs.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность
pjs/netwerk/streamconv/converters/nsUnknownDecoder.cpp

738 строки
22 KiB
C++
Исходник Ответственный История

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsUnknownDecoder.h"
#include "nsIServiceManager.h"
#include "nsIStreamConverterService.h"
#include "nsIPipe.h"
#include "nsIInputStream.h"
#include "nsIOutputStream.h"
#include "nsMimeTypes.h"
#include "netCore.h"
#include "nsXPIDLString.h"
#include "nsIPrefService.h"
#include "nsIPrefBranch.h"
#include "nsICategoryManager.h"
#include "nsISupportsPrimitives.h"
#include "nsIContentSniffer.h"
#include "nsCRT.h"
#include "nsIMIMEService.h"
#include "nsIViewSourceChannel.h"
#include "nsIHttpChannel.h"
#include "nsNetCID.h"
#define MAX_BUFFER_SIZE 512
nsUnknownDecoder::nsUnknownDecoder()
: mBuffer(nsnull)
, mBufferLen(0)
, mRequireHTMLsuffix(PR_FALSE)
{
nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
if (prefs) {
PRBool val;
if (NS_SUCCEEDED(prefs->GetBoolPref("security.requireHTMLsuffix", &val)))
mRequireHTMLsuffix = val;
}
}
nsUnknownDecoder::~nsUnknownDecoder()
{
if (mBuffer) {
delete [] mBuffer;
mBuffer = nsnull;
}
}
// ----
//
// nsISupports implementation...
//
// ----
NS_IMPL_ADDREF(nsUnknownDecoder)
NS_IMPL_RELEASE(nsUnknownDecoder)
NS_INTERFACE_MAP_BEGIN(nsUnknownDecoder)
NS_INTERFACE_MAP_ENTRY(nsIStreamConverter)
NS_INTERFACE_MAP_ENTRY(nsIStreamListener)
NS_INTERFACE_MAP_ENTRY(nsIRequestObserver)
NS_INTERFACE_MAP_ENTRY(nsIContentSniffer)
NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIStreamListener)
NS_INTERFACE_MAP_END
// ----
//
// nsIStreamConverter methods...
//
// ----
NS_IMETHODIMP
nsUnknownDecoder::Convert(nsIInputStream *aFromStream,
const char *aFromType,
const char *aToType,
nsISupports *aCtxt,
nsIInputStream **aResultStream)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsUnknownDecoder::AsyncConvertData(const char *aFromType,
const char *aToType,
nsIStreamListener *aListener,
nsISupports *aCtxt)
{
NS_ASSERTION(aListener && aFromType && aToType,
"null pointer passed into multi mixed converter");
// hook up our final listener. this guy gets the various On*() calls we want to throw
// at him.
//
mNextListener = aListener;
return (aListener) ? NS_OK : NS_ERROR_FAILURE;
}
// ----
//
// nsIStreamListener methods...
//
// ----
NS_IMETHODIMP
nsUnknownDecoder::OnDataAvailable(nsIRequest* request,
nsISupports *aCtxt,
nsIInputStream *aStream,
PRUint32 aSourceOffset,
PRUint32 aCount)
{
nsresult rv = NS_OK;
if (!mNextListener) return NS_ERROR_FAILURE;
if (mContentType.IsEmpty()) {
PRUint32 count, len;
// If the buffer has not been allocated by now, just fail...
if (!mBuffer) return NS_ERROR_OUT_OF_MEMORY;
//
// Determine how much of the stream should be read to fill up the
// sniffer buffer...
//
if (mBufferLen + aCount >= MAX_BUFFER_SIZE) {
count = MAX_BUFFER_SIZE-mBufferLen;
} else {
count = aCount;
}
// Read the data into the buffer...
rv = aStream->Read((mBuffer+mBufferLen), count, &len);
if (NS_FAILED(rv)) return rv;
mBufferLen += len;
aCount -= len;
if (aCount) {
//
// Adjust the source offset... The call to FireListenerNotifications(...)
// will make the first OnDataAvailable(...) call with an offset of 0.
// So, this offset needs to be adjusted to reflect that...
//
aSourceOffset += mBufferLen;
DetermineContentType(request);
rv = FireListenerNotifications(request, aCtxt);
}
}
// Must not fire ODA again if it failed once
if (aCount && NS_SUCCEEDED(rv)) {
NS_ASSERTION(!mContentType.IsEmpty(),
"Content type should be known by now.");
rv = mNextListener->OnDataAvailable(request, aCtxt, aStream,
aSourceOffset, aCount);
}
return rv;
}
// ----
//
// nsIRequestObserver methods...
//
// ----
NS_IMETHODIMP
nsUnknownDecoder::OnStartRequest(nsIRequest* request, nsISupports *aCtxt)
{
nsresult rv = NS_OK;
if (!mNextListener) return NS_ERROR_FAILURE;
// Allocate the sniffer buffer...
if (NS_SUCCEEDED(rv) && !mBuffer) {
mBuffer = new char[MAX_BUFFER_SIZE];
if (!mBuffer) {
rv = NS_ERROR_OUT_OF_MEMORY;
}
}
// Do not pass the OnStartRequest on to the next listener (yet)...
return rv;
}
NS_IMETHODIMP
nsUnknownDecoder::OnStopRequest(nsIRequest* request, nsISupports *aCtxt,
nsresult aStatus)
{
nsresult rv = NS_OK;
if (!mNextListener) return NS_ERROR_FAILURE;
//
// The total amount of data is less than the size of the sniffer buffer.
// Analyze the buffer now...
//
if (mContentType.IsEmpty()) {
DetermineContentType(request);
rv = FireListenerNotifications(request, aCtxt);
if (NS_FAILED(rv)) {
aStatus = rv;
}
}
rv = mNextListener->OnStopRequest(request, aCtxt, aStatus);
mNextListener = 0;
return rv;
}
// ----
//
// nsIContentSniffer methods...
//
// ----
NS_IMETHODIMP
nsUnknownDecoder::GetMIMETypeFromContent(nsIRequest* aRequest,
const PRUint8* aData,
PRUint32 aLength,
nsACString& type)
{
mBuffer = const_cast<char*>(reinterpret_cast<const char*>(aData));
mBufferLen = aLength;
DetermineContentType(aRequest);
mBuffer = nsnull;
mBufferLen = 0;
type.Assign(mContentType);
mContentType.Truncate();
return type.IsEmpty() ? NS_ERROR_NOT_AVAILABLE : NS_OK;
}
// Actual sniffing code
PRBool nsUnknownDecoder::AllowSniffing(nsIRequest* aRequest)
{
if (!mRequireHTMLsuffix) {
return PR_TRUE;
}
nsCOMPtr<nsIChannel> channel = do_QueryInterface(aRequest);
if (!channel) {
NS_ERROR("QI failed");
return PR_FALSE;
}
nsCOMPtr<nsIURI> uri;
if (NS_FAILED(channel->GetURI(getter_AddRefs(uri))) || !uri) {
return PR_FALSE;
}
PRBool isLocalFile = PR_FALSE;
if (NS_FAILED(uri->SchemeIs("file", &isLocalFile)) || isLocalFile) {
return PR_FALSE;
}
return PR_TRUE;
}
/**
* This is the array of sniffer entries that depend on "magic numbers"
* in the file. Each entry has either a type associated with it (set
* these with the SNIFFER_ENTRY macro) or a function to be executed
* (set these with the SNIFFER_ENTRY_WITH_FUNC macro). The function
* should take a single nsIRequest* and returns PRBool -- PR_TRUE if
* it sets mContentType, PR_FALSE otherwise
*/
nsUnknownDecoder::nsSnifferEntry nsUnknownDecoder::sSnifferEntries[] = {
SNIFFER_ENTRY("%PDF-", APPLICATION_PDF),
SNIFFER_ENTRY("%!PS-Adobe-", APPLICATION_POSTSCRIPT),
// Files that start with mailbox delimiters let's provisionally call
// text/plain
SNIFFER_ENTRY("From", TEXT_PLAIN),
SNIFFER_ENTRY(">From", TEXT_PLAIN),
// If the buffer begins with "#!" or "%!" then it is a script of
// some sort... "Scripts" can include arbitrary data to be passed
// to an interpreter, so we need to decide whether we can call this
// text or whether it's data.
SNIFFER_ENTRY_WITH_FUNC("#!", &nsUnknownDecoder::LastDitchSniff),
// XXXbz should (and can) we also include the various ways that <?xml can
// appear as UTF-16 and such? See http://www.w3.org/TR/REC-xml#sec-guessing
SNIFFER_ENTRY_WITH_FUNC("<?xml", &nsUnknownDecoder::SniffForXML)
};
PRUint32 nsUnknownDecoder::sSnifferEntryNum =
sizeof(nsUnknownDecoder::sSnifferEntries) /
sizeof(nsUnknownDecoder::nsSnifferEntry);
void nsUnknownDecoder::DetermineContentType(nsIRequest* aRequest)
{
NS_ASSERTION(mContentType.IsEmpty(), "Content type is already known.");
if (!mContentType.IsEmpty()) return;
// First, run through all the types we can detect reliably based on
// magic numbers
PRUint32 i;
for (i = 0; i < sSnifferEntryNum; ++i) {
if (mBufferLen >= sSnifferEntries[i].mByteLen && // enough data
memcmp(mBuffer, sSnifferEntries[i].mBytes, sSnifferEntries[i].mByteLen) == 0) { // and type matches
NS_ASSERTION(sSnifferEntries[i].mMimeType ||
sSnifferEntries[i].mContentTypeSniffer,
"Must have either a type string or a function to set the type");
NS_ASSERTION(sSnifferEntries[i].mMimeType == nsnull ||
sSnifferEntries[i].mContentTypeSniffer == nsnull,
"Both a type string and a type sniffing function set;"
" using type string");
if (sSnifferEntries[i].mMimeType) {
mContentType = sSnifferEntries[i].mMimeType;
NS_ASSERTION(!mContentType.IsEmpty(),
"Content type should be known by now.");
return;
}
if ((this->*(sSnifferEntries[i].mContentTypeSniffer))(aRequest)) {
NS_ASSERTION(!mContentType.IsEmpty(),
"Content type should be known by now.");
return;
}
}
}
if (TryContentSniffers(aRequest)) {
NS_ASSERTION(!mContentType.IsEmpty(),
"Content type should be known by now.");
return;
}
if (SniffForHTML(aRequest)) {
NS_ASSERTION(!mContentType.IsEmpty(),
"Content type should be known by now.");
return;
}
// We don't know what this is yet. Before we just give up, try
// the URI from the request.
if (SniffURI(aRequest)) {
NS_ASSERTION(!mContentType.IsEmpty(),
"Content type should be known by now.");
return;
}
LastDitchSniff(aRequest);
NS_ASSERTION(!mContentType.IsEmpty(),
"Content type should be known by now.");
}
PRBool nsUnknownDecoder::TryContentSniffers(nsIRequest* aRequest)
{
// Enumerate content sniffers
nsCOMPtr<nsICategoryManager> catMan(do_GetService("@mozilla.org/categorymanager;1"));
if (!catMan) {
return PR_FALSE;
}
nsCOMPtr<nsISimpleEnumerator> sniffers;
catMan->EnumerateCategory("content-sniffing-services", getter_AddRefs(sniffers));
if (!sniffers) {
return PR_FALSE;
}
PRBool hasMore;
while (NS_SUCCEEDED(sniffers->HasMoreElements(&hasMore)) && hasMore) {
nsCOMPtr<nsISupports> elem;
sniffers->GetNext(getter_AddRefs(elem));
NS_ASSERTION(elem, "No element even though hasMore returned true!?");
nsCOMPtr<nsISupportsCString> sniffer_id(do_QueryInterface(elem));
NS_ASSERTION(sniffer_id, "element is no nsISupportsCString!?");
nsCAutoString contractid;
nsresult rv = sniffer_id->GetData(contractid);
if (NS_FAILED(rv)) {
continue;
}
nsCOMPtr<nsIContentSniffer> sniffer(do_GetService(contractid.get()));
if (!sniffer) {
continue;
}
rv = sniffer->GetMIMETypeFromContent(aRequest, (const PRUint8*)mBuffer,
mBufferLen, mContentType);
if (NS_SUCCEEDED(rv)) {
return PR_TRUE;
}
}
return PR_FALSE;
}
PRBool nsUnknownDecoder::SniffForHTML(nsIRequest* aRequest)
{
/*
* To prevent a possible attack, we will not consider this to be
* html content if it comes from the local file system and our prefs
* are set right
*/
if (!AllowSniffing(aRequest)) {
return PR_FALSE;
}
// Now look for HTML.
const char* str = mBuffer;
const char* end = mBuffer + mBufferLen;
// skip leading whitespace
while (str != end && nsCRT::IsAsciiSpace(*str)) {
++str;
}
// did we find something like a start tag?
if (str == end || *str != '<' || ++str == end) {
return PR_FALSE;
}
// If we seem to be SGML or XML and we got down here, just pretend we're HTML
if (*str == '!' || *str == '?') {
mContentType = TEXT_HTML;
return PR_TRUE;
}
PRUint32 bufSize = end - str;
// We use sizeof(_tagstr) below because that's the length of _tagstr
// with the one char " " or ">" appended.
#define MATCHES_TAG(_tagstr) \
(bufSize >= sizeof(_tagstr) && \
(PL_strncasecmp(str, _tagstr " ", sizeof(_tagstr)) == 0 || \
PL_strncasecmp(str, _tagstr ">", sizeof(_tagstr)) == 0))
if (MATCHES_TAG("html") ||
MATCHES_TAG("frameset") ||
MATCHES_TAG("body") ||
MATCHES_TAG("head") ||
MATCHES_TAG("script") ||
MATCHES_TAG("iframe") ||
MATCHES_TAG("a") ||
MATCHES_TAG("img") ||
MATCHES_TAG("table") ||
MATCHES_TAG("title") ||
MATCHES_TAG("link") ||
MATCHES_TAG("base") ||
MATCHES_TAG("style") ||
MATCHES_TAG("div") ||
MATCHES_TAG("p") ||
MATCHES_TAG("font") ||
MATCHES_TAG("applet") ||
MATCHES_TAG("meta") ||
MATCHES_TAG("center") ||
MATCHES_TAG("form") ||
MATCHES_TAG("isindex") ||
MATCHES_TAG("h1") ||
MATCHES_TAG("h2") ||
MATCHES_TAG("h3") ||
MATCHES_TAG("h4") ||
MATCHES_TAG("h5") ||
MATCHES_TAG("h6") ||
MATCHES_TAG("b") ||
MATCHES_TAG("pre")) {
mContentType = TEXT_HTML;
return PR_TRUE;
}
#undef MATCHES_TAG
return PR_FALSE;
}
PRBool nsUnknownDecoder::SniffForXML(nsIRequest* aRequest)
{
// Just like HTML, this should be able to be shut off.
if (!AllowSniffing(aRequest)) {
return PR_FALSE;
}
// First see whether we can glean anything from the uri...
if (!SniffURI(aRequest)) {
// Oh well; just generic XML will have to do
mContentType = TEXT_XML;
}
return PR_TRUE;
}
PRBool nsUnknownDecoder::SniffURI(nsIRequest* aRequest)
{
nsCOMPtr<nsIMIMEService> mimeService(do_GetService("@mozilla.org/mime;1"));
if (mimeService) {
nsCOMPtr<nsIChannel> channel = do_QueryInterface(aRequest);
if (channel) {
nsCOMPtr<nsIURI> uri;
nsresult result = channel->GetURI(getter_AddRefs(uri));
if (NS_SUCCEEDED(result) && uri) {
nsCAutoString type;
result = mimeService->GetTypeFromURI(uri, type);
if (NS_SUCCEEDED(result)) {
mContentType = type;
return PR_TRUE;
}
}
}
}
return PR_FALSE;
}
// This macro is based on RFC 2046 Section 4.1.2. Treat any char 0-31
// except the 9-13 range (\t, \n, \v, \f, \r) and char 27 (used by
// encodings like Shift_JIS) as non-text
#define IS_TEXT_CHAR(ch) \
(((unsigned char)(ch)) > 31 || (9 <= (ch) && (ch) <= 13) || (ch) == 27)
PRBool nsUnknownDecoder::LastDitchSniff(nsIRequest* aRequest)
{
// All we can do now is try to guess whether this is text/plain or
// application/octet-stream
// First, check for a BOM. If we see one, assume this is text/plain
// in whatever encoding. If there is a BOM _and_ text we will
// always have at least 4 bytes in the buffer (since the 2-byte BOMs
// are for 2-byte encodings and the UTF-8 BOM is 3 bytes).
if (mBufferLen >= 4) {
const unsigned char* buf = (const unsigned char*)mBuffer;
if ((buf[0] == 0xFE && buf[1] == 0xFF) || // UTF-16, Big Endian
(buf[0] == 0xFF && buf[1] == 0xFE) || // UTF-16 or UCS-4, Little Endian
(buf[0] == 0xEF && buf[1] == 0xBB && buf[2] == 0xBF) || // UTF-8
(buf[0] == 0 && buf[1] == 0 && buf[2] == 0xFE && buf[3] == 0xFF)) { // UCS-4, Big Endian
mContentType = TEXT_PLAIN;
return PR_TRUE;
}
}
// Now see whether the buffer has any non-text chars. If not, then let's
// just call it text/plain...
//
PRUint32 i;
for (i=0; i<mBufferLen && IS_TEXT_CHAR(mBuffer[i]); i++);
if (i == mBufferLen) {
mContentType = TEXT_PLAIN;
}
else {
mContentType = APPLICATION_OCTET_STREAM;
}
return PR_TRUE;
}
nsresult nsUnknownDecoder::FireListenerNotifications(nsIRequest* request,
nsISupports *aCtxt)
{
nsresult rv = NS_OK;
if (!mNextListener) return NS_ERROR_FAILURE;
if (!mContentType.IsEmpty()) {
nsCOMPtr<nsIViewSourceChannel> viewSourceChannel =
do_QueryInterface(request);
if (viewSourceChannel) {
rv = viewSourceChannel->SetOriginalContentType(mContentType);
} else {
nsCOMPtr<nsIChannel> channel = do_QueryInterface(request, &rv);
if (NS_SUCCEEDED(rv)) {
// Set the new content type on the channel...
rv = channel->SetContentType(mContentType);
}
}
NS_ASSERTION(NS_SUCCEEDED(rv), "Unable to set content type on channel!");
if (NS_FAILED(rv)) {
// Cancel the request to make sure it has the correct status if
// mNextListener looks at it.
request->Cancel(rv);
mNextListener->OnStartRequest(request, aCtxt);
return rv;
}
}
// Fire the OnStartRequest(...)
rv = mNextListener->OnStartRequest(request, aCtxt);
if (!mBuffer) return NS_ERROR_OUT_OF_MEMORY;
// If the request was canceled, then we need to treat that equivalently
// to an error returned by OnStartRequest.
if (NS_SUCCEEDED(rv))
request->GetStatus(&rv);
// Fire the first OnDataAvailable for the data that was read from the
// stream into the sniffer buffer...
if (NS_SUCCEEDED(rv) && (mBufferLen > 0)) {
PRUint32 len = 0;
nsCOMPtr<nsIInputStream> in;
nsCOMPtr<nsIOutputStream> out;
// Create a pipe and fill it with the data from the sniffer buffer.
rv = NS_NewPipe(getter_AddRefs(in), getter_AddRefs(out),
MAX_BUFFER_SIZE, MAX_BUFFER_SIZE);
if (NS_SUCCEEDED(rv)) {
rv = out->Write(mBuffer, mBufferLen, &len);
if (NS_SUCCEEDED(rv)) {
if (len == mBufferLen) {
rv = mNextListener->OnDataAvailable(request, aCtxt, in, 0, len);
} else {
NS_ERROR("Unable to write all the data into the pipe.");
rv = NS_ERROR_FAILURE;
}
}
}
}
delete [] mBuffer;
mBuffer = nsnull;
mBufferLen = 0;
return rv;
}
void
nsBinaryDetector::DetermineContentType(nsIRequest* aRequest)
{
nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(aRequest);
if (!httpChannel) {
return;
}
// It's an HTTP channel. Check for the text/plain mess
nsCAutoString contentTypeHdr;
httpChannel->GetResponseHeader(NS_LITERAL_CSTRING("Content-Type"),
contentTypeHdr);
nsCAutoString contentType;
httpChannel->GetContentType(contentType);
// Make sure to do a case-sensitive exact match comparison here. Apache
// 1.x just sends text/plain for "unknown", while Apache 2.x sends
// text/plain with a ISO-8859-1 charset. Debian's Apache version, just to
// be different, sends text/plain with iso-8859-1 charset. For extra fun,
// FC7, RHEL4, and Ubuntu Feisty send charset=UTF-8. Don't do general
// case-insensitive comparison, since we really want to apply this crap as
// rarely as we can.
if (!contentType.EqualsLiteral("text/plain") ||
(!contentTypeHdr.EqualsLiteral("text/plain") &&
!contentTypeHdr.EqualsLiteral("text/plain; charset=ISO-8859-1") &&
!contentTypeHdr.EqualsLiteral("text/plain; charset=iso-8859-1") &&
!contentTypeHdr.EqualsLiteral("text/plain; charset=UTF-8"))) {
return;
}
// Check whether we have content-encoding. If we do, don't try to
// detect the type.
// XXXbz we could improve this by doing a local decompress if we
// wanted, I'm sure.
nsCAutoString contentEncoding;
httpChannel->GetResponseHeader(NS_LITERAL_CSTRING("Content-Encoding"),
contentEncoding);
if (!contentEncoding.IsEmpty()) {
return;
}
LastDitchSniff(aRequest);
if (mContentType.Equals(APPLICATION_OCTET_STREAM)) {
// We want to guess at it instead
mContentType = APPLICATION_GUESS_FROM_EXT;
} else {
// Let the text/plain type we already have be, so that other content
// sniffers can also get a shot at this data.
mContentType.Truncate();
}
}
NS_METHOD
nsBinaryDetector::Register(nsIComponentManager* compMgr, nsIFile* path,
const char* registryLocation,
const char* componentType,
const nsModuleComponentInfo *info)
{
nsresult rv;
nsCOMPtr<nsICategoryManager> catman =
do_GetService(NS_CATEGORYMANAGER_CONTRACTID, &rv);
if (NS_FAILED(rv))
return rv;
return catman->AddCategoryEntry(NS_CONTENT_SNIFFER_CATEGORY,
"Binary Detector",
NS_BINARYDETECTOR_CONTRACTID,
PR_TRUE, PR_TRUE, nsnull);
}
Ссылка в новой задаче Показать git blame Копировать постоянную ссылку