The Tor Browser: image/decoders/icon/mac/nsIconChannelCocoa.mm@ac0c01689b40 (annotated)

image/decoders/icon/mac/nsIconChannelCocoa.mm@ac0c01689b40 (annotated)

image/decoders/icon/mac/nsIconChannelCocoa.mm

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rw-r--r--

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*-
  *
  * 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 "nsIconChannel.h"
 #include "mozilla/Endian.h"
 #include "nsIIconURI.h"
 #include "nsIServiceManager.h"
 #include "nsIInterfaceRequestor.h"
 #include "nsIInterfaceRequestorUtils.h"
 #include "nsXPIDLString.h"
 #include "nsMimeTypes.h"
 #include "nsMemory.h"
 #include "nsIStringStream.h"
 #include "nsIURL.h"
 #include "nsNetUtil.h"
 #include "nsIMIMEService.h"
 #include "nsCExternalHandlerService.h"
 #include "nsILocalFileMac.h"
 #include "nsIFileURL.h"
 #include "nsTArray.h"
 #include "nsObjCExceptions.h"
 #include <Cocoa/Cocoa.h>
 // nsIconChannel methods
 nsIconChannel::nsIconChannel()
 {
 }
 nsIconChannel::~nsIconChannel()
 {}
 NS_IMPL_ISUPPORTS(nsIconChannel,
                   nsIChannel,
                   nsIRequest,
 			       nsIRequestObserver,
 			       nsIStreamListener)
 nsresult nsIconChannel::Init(nsIURI* uri)
 {
   NS_ASSERTION(uri, "no uri");
   mUrl = uri;
   mOriginalURI = uri;
   nsresult rv;
   mPump = do_CreateInstance(NS_INPUTSTREAMPUMP_CONTRACTID, &rv);
   return rv;
 }
 ////////////////////////////////////////////////////////////////////////////////
 // nsIRequest methods:
 NS_IMETHODIMP nsIconChannel::GetName(nsACString &result)
 {
   return mUrl->GetSpec(result);
 }
 NS_IMETHODIMP nsIconChannel::IsPending(bool *result)
 {
   return mPump->IsPending(result);
 }
 NS_IMETHODIMP nsIconChannel::GetStatus(nsresult *status)
 {
   return mPump->GetStatus(status);
 }
 NS_IMETHODIMP nsIconChannel::Cancel(nsresult status)
 {
   return mPump->Cancel(status);
 }
 NS_IMETHODIMP nsIconChannel::Suspend(void)
 {
   return mPump->Suspend();
 }
 NS_IMETHODIMP nsIconChannel::Resume(void)
 {
   return mPump->Resume();
 }
 // nsIRequestObserver methods
 NS_IMETHODIMP nsIconChannel::OnStartRequest(nsIRequest* aRequest, nsISupports* aContext)
 {
   if (mListener)
     return mListener->OnStartRequest(this, aContext);
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::OnStopRequest(nsIRequest* aRequest, nsISupports* aContext, nsresult aStatus)
 {
   if (mListener) {
     mListener->OnStopRequest(this, aContext, aStatus);
     mListener = nullptr;
   }
   // Remove from load group
   if (mLoadGroup)
     mLoadGroup->RemoveRequest(this, nullptr, aStatus);
   return NS_OK;
 }
 // nsIStreamListener methods
 NS_IMETHODIMP nsIconChannel::OnDataAvailable(nsIRequest* aRequest,
                                              nsISupports* aContext,
                                              nsIInputStream* aStream,
                                              uint64_t aOffset,
                                              uint32_t aCount)
 {
   if (mListener)
     return mListener->OnDataAvailable(this, aContext, aStream, aOffset, aCount);
   return NS_OK;
 }
 ////////////////////////////////////////////////////////////////////////////////
 // nsIChannel methods:
 NS_IMETHODIMP nsIconChannel::GetOriginalURI(nsIURI* *aURI)
 {
   *aURI = mOriginalURI;
   NS_ADDREF(*aURI);
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::SetOriginalURI(nsIURI* aURI)
 {
   NS_ENSURE_ARG_POINTER(aURI);
   mOriginalURI = aURI;
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::GetURI(nsIURI* *aURI)
 {
   *aURI = mUrl;
   NS_IF_ADDREF(*aURI);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsIconChannel::Open(nsIInputStream **_retval)
 {
   return MakeInputStream(_retval, false);
 }
 nsresult nsIconChannel::ExtractIconInfoFromUrl(nsIFile ** aLocalFile, uint32_t * aDesiredImageSize, nsACString &aContentType, nsACString &aFileExtension)
 {
   nsresult rv = NS_OK;
   nsCOMPtr<nsIMozIconURI> iconURI (do_QueryInterface(mUrl, &rv));
   NS_ENSURE_SUCCESS(rv, rv);
   iconURI->GetImageSize(aDesiredImageSize);
   iconURI->GetContentType(aContentType);
   iconURI->GetFileExtension(aFileExtension);
   nsCOMPtr<nsIURL> url;
   rv = iconURI->GetIconURL(getter_AddRefs(url));
   if (NS_FAILED(rv) || !url) return NS_OK;
   nsCOMPtr<nsIFileURL> fileURL = do_QueryInterface(url, &rv);
   if (NS_FAILED(rv) || !fileURL) return NS_OK;
   nsCOMPtr<nsIFile> file;
   rv = fileURL->GetFile(getter_AddRefs(file));
   if (NS_FAILED(rv) || !file) return NS_OK;
   nsCOMPtr<nsILocalFileMac> localFileMac (do_QueryInterface(file, &rv));
   if (NS_FAILED(rv) || !localFileMac) return NS_OK;
   *aLocalFile = file;
   NS_IF_ADDREF(*aLocalFile);
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::AsyncOpen(nsIStreamListener *aListener, nsISupports *ctxt)
 {
   nsCOMPtr<nsIInputStream> inStream;
   nsresult rv = MakeInputStream(getter_AddRefs(inStream), true);
   NS_ENSURE_SUCCESS(rv, rv);
   // Init our stream pump
   rv = mPump->Init(inStream, int64_t(-1), int64_t(-1), 0, 0, false);
   NS_ENSURE_SUCCESS(rv, rv);
   rv = mPump->AsyncRead(this, ctxt);
   if (NS_SUCCEEDED(rv)) {
     // Store our real listener
     mListener = aListener;
     // Add ourself to the load group, if available
     if (mLoadGroup)
       mLoadGroup->AddRequest(this, nullptr);
   }
   return rv;
 }
 nsresult nsIconChannel::MakeInputStream(nsIInputStream** _retval, bool nonBlocking)
 {
   NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;
   nsXPIDLCString contentType;
   nsAutoCString fileExt;
   nsCOMPtr<nsIFile> fileloc; // file we want an icon for
   uint32_t desiredImageSize;
   nsresult rv = ExtractIconInfoFromUrl(getter_AddRefs(fileloc), &desiredImageSize, contentType, fileExt);
   NS_ENSURE_SUCCESS(rv, rv);
   bool fileExists = false;
   if (fileloc) {
     // ensure that we DO NOT resolve aliases, very important for file views
     fileloc->SetFollowLinks(false);
     fileloc->Exists(&fileExists);
   }
   NSImage* iconImage = nil;
   // first try to get the icon from the file if it exists
   if (fileExists) {
     nsCOMPtr<nsILocalFileMac> localFileMac(do_QueryInterface(fileloc, &rv));
     NS_ENSURE_SUCCESS(rv, rv);
     CFURLRef macURL;
     if (NS_SUCCEEDED(localFileMac->GetCFURL(&macURL))) {
       iconImage = [[NSWorkspace sharedWorkspace] iconForFile:[(NSURL*)macURL path]];
       ::CFRelease(macURL);
     }
   }
   // if we don't have an icon yet try to get one by extension
   if (!iconImage && !fileExt.IsEmpty()) {
     NSString* fileExtension = [NSString stringWithUTF8String:fileExt.get()];
     iconImage = [[NSWorkspace sharedWorkspace] iconForFileType:fileExtension];
   }
   // If we still don't have an icon, get the generic document icon.
   if (!iconImage)
     iconImage = [[NSWorkspace sharedWorkspace] iconForFileType:NSFileTypeUnknown];
   if (!iconImage)
     return NS_ERROR_FAILURE;
   // we have an icon now, size it
   NSRect desiredSizeRect = NSMakeRect(0, 0, desiredImageSize, desiredImageSize);
   [iconImage setSize:desiredSizeRect.size];
   [iconImage lockFocus];
   NSBitmapImageRep* bitmapRep = [[[NSBitmapImageRep alloc] initWithFocusedViewRect:desiredSizeRect] autorelease];
   [iconImage unlockFocus];
   // we expect the following things to be true about our bitmapRep
   NS_ENSURE_TRUE(![bitmapRep isPlanar] &&
                  // Not necessarily: on a HiDPI-capable system, we'll get a 2x bitmap
                  // (unsigned int)[bitmapRep bytesPerPlane] == desiredImageSize * desiredImageSize * 4 &&
                  [bitmapRep bitsPerPixel] == 32 &&
                  [bitmapRep samplesPerPixel] == 4 &&
                  [bitmapRep hasAlpha] == YES,
                  NS_ERROR_UNEXPECTED);
   // check what size we actually got, and ensure it isn't too big to return
   uint32_t actualImageSize = [bitmapRep bytesPerRow] / 4;
   NS_ENSURE_TRUE(actualImageSize < 256, NS_ERROR_UNEXPECTED);
   // now we can validate the amount of data
   NS_ENSURE_TRUE((unsigned int)[bitmapRep bytesPerPlane] == actualImageSize * actualImageSize * 4,
                  NS_ERROR_UNEXPECTED);
   // rgba, pre-multiplied data
   uint8_t* bitmapRepData = (uint8_t*)[bitmapRep bitmapData];
   // create our buffer
   int32_t bufferCapacity = 2 + [bitmapRep bytesPerPlane];
   nsAutoTArray<uint8_t, 3 + 16 * 16 * 5> iconBuffer; // initial size is for 16x16
   iconBuffer.SetLength(bufferCapacity);
   uint8_t* iconBufferPtr = iconBuffer.Elements();
   // write header data into buffer
   *iconBufferPtr++ = actualImageSize;
   *iconBufferPtr++ = actualImageSize;
   uint32_t dataCount = [bitmapRep bytesPerPlane];
   uint32_t index = 0;
   while (index < dataCount) {
     // get data from the bitmap
     uint8_t r = bitmapRepData[index++];
     uint8_t g = bitmapRepData[index++];
     uint8_t b = bitmapRepData[index++];
     uint8_t a = bitmapRepData[index++];
     // write data out to our buffer
     // non-cairo uses native image format, but the A channel is ignored.
     // cairo uses ARGB (highest to lowest bits)
 #if MOZ_LITTLE_ENDIAN
     *iconBufferPtr++ = b;
     *iconBufferPtr++ = g;
     *iconBufferPtr++ = r;
     *iconBufferPtr++ = a;
 #else
     *iconBufferPtr++ = a;
     *iconBufferPtr++ = r;
     *iconBufferPtr++ = g;
     *iconBufferPtr++ = b;
 #endif
   }
   NS_ASSERTION(iconBufferPtr == iconBuffer.Elements() + bufferCapacity,
                "buffer size miscalculation");
   // Now, create a pipe and stuff our data into it
   nsCOMPtr<nsIInputStream> inStream;
   nsCOMPtr<nsIOutputStream> outStream;
   rv = NS_NewPipe(getter_AddRefs(inStream), getter_AddRefs(outStream),
                   bufferCapacity, bufferCapacity, nonBlocking);
   if (NS_SUCCEEDED(rv)) {
     uint32_t written;
     rv = outStream->Write((char*)iconBuffer.Elements(), bufferCapacity, &written);
     if (NS_SUCCEEDED(rv))
       NS_IF_ADDREF(*_retval = inStream);
   }
   // Drop notification callbacks to prevent cycles.
   mCallbacks = nullptr;
   return NS_OK;
   NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
 }
 NS_IMETHODIMP nsIconChannel::GetLoadFlags(uint32_t *aLoadAttributes)
 {
   return mPump->GetLoadFlags(aLoadAttributes);
 }
 NS_IMETHODIMP nsIconChannel::SetLoadFlags(uint32_t aLoadAttributes)
 {
   return mPump->SetLoadFlags(aLoadAttributes);
 }
 NS_IMETHODIMP nsIconChannel::GetContentType(nsACString &aContentType)
 {
   aContentType.AssignLiteral(IMAGE_ICON_MS);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsIconChannel::SetContentType(const nsACString &aContentType)
 {
   //It doesn't make sense to set the content-type on this type
   // of channel...
   return NS_ERROR_FAILURE;
 }
 NS_IMETHODIMP nsIconChannel::GetContentCharset(nsACString &aContentCharset)
 {
   aContentCharset.AssignLiteral(IMAGE_ICON_MS);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsIconChannel::SetContentCharset(const nsACString &aContentCharset)
 {
   //It doesn't make sense to set the content-type on this type
   // of channel...
   return NS_ERROR_FAILURE;
 }
 NS_IMETHODIMP
 nsIconChannel::GetContentDisposition(uint32_t *aContentDisposition)
 {
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP
 nsIconChannel::SetContentDisposition(uint32_t aContentDisposition)
 {
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP
 nsIconChannel::GetContentDispositionFilename(nsAString &aContentDispositionFilename)
 {
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP
 nsIconChannel::SetContentDispositionFilename(const nsAString &aContentDispositionFilename)
 {
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP
 nsIconChannel::GetContentDispositionHeader(nsACString &aContentDispositionHeader)
 {
   return NS_ERROR_NOT_AVAILABLE;
 }
 NS_IMETHODIMP nsIconChannel::GetContentLength(int64_t *aContentLength)
 {
   *aContentLength = mContentLength;
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::SetContentLength(int64_t aContentLength)
 {
   NS_NOTREACHED("nsIconChannel::SetContentLength");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 NS_IMETHODIMP nsIconChannel::GetLoadGroup(nsILoadGroup* *aLoadGroup)
 {
   *aLoadGroup = mLoadGroup;
   NS_IF_ADDREF(*aLoadGroup);
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::SetLoadGroup(nsILoadGroup* aLoadGroup)
 {
   mLoadGroup = aLoadGroup;
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::GetOwner(nsISupports* *aOwner)
 {
   *aOwner = mOwner.get();
   NS_IF_ADDREF(*aOwner);
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::SetOwner(nsISupports* aOwner)
 {
   mOwner = aOwner;
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::GetNotificationCallbacks(nsIInterfaceRequestor* *aNotificationCallbacks)
 {
   *aNotificationCallbacks = mCallbacks.get();
   NS_IF_ADDREF(*aNotificationCallbacks);
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::SetNotificationCallbacks(nsIInterfaceRequestor* aNotificationCallbacks)
 {
   mCallbacks = aNotificationCallbacks;
   return NS_OK;
 }
 NS_IMETHODIMP nsIconChannel::GetSecurityInfo(nsISupports * *aSecurityInfo)
 {
   *aSecurityInfo = nullptr;
   return NS_OK;
 }

The Tor Browser / annotate

image/decoders/icon/mac/nsIconChannelCocoa.mm@ac0c01689b40 (annotated)

image/decoders/icon/mac/nsIconChannelCocoa.mm