Add support for running the NaCl plugin in the Linux SUID sandbox

chrome/renderer/renderer_sandbox_support_linux.cc

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.  Use of this
 // source code is governed by a BSD-style license that can be found in the
 // LICENSE file.
 
 #include "chrome/renderer/renderer_sandbox_support_linux.h"
 
 #include "base/global_descriptors_posix.h"
 #include "base/pickle.h"
 #include "base/unix_domain_socket_posix.h"
 #include "chrome/common/chrome_descriptors.h"
 #include "chrome/common/sandbox_methods_linux.h"
 
 #include "third_party/WebKit/WebKit/chromium/public/linux/WebFontRenderStyle.h"
 
+static int GetSandboxFD() {
+  return kSandboxIPCChannel + base::GlobalDescriptors::kBaseDescriptor;
+}
+
 namespace renderer_sandbox_support {
 
 std::string getFontFamilyForCharacters(const uint16_t* utf16, size_t num_utf16) {
   Pickle request;
   request.WriteInt(LinuxSandbox::METHOD_GET_FONT_FAMILY_FOR_CHARS);
   request.WriteInt(num_utf16);
   for (size_t i = 0; i < num_utf16; ++i)
     request.WriteUInt32(utf16[i]);
 
   uint8_t buf[512];
-  const int sandbox_fd =
-    kSandboxIPCChannel + base::GlobalDescriptors::kBaseDescriptor;
-  const ssize_t n = base::SendRecvMsg(sandbox_fd, buf, sizeof(buf), NULL,
+  const ssize_t n = base::SendRecvMsg(GetSandboxFD(), buf, sizeof(buf), NULL,
                                       request);
 
   std::string family_name;
   if (n != -1) {
     Pickle reply(reinterpret_cast<char*>(buf), n);
     void* pickle_iter = NULL;
     reply.ReadString(&pickle_iter, &family_name);
   }
 
   return family_name;
 }
 
 void getRenderStyleForStrike(const char* family, int sizeAndStyle,
                              WebKit::WebFontRenderStyle* out) {
   Pickle request;
   request.WriteInt(LinuxSandbox::METHOD_GET_STYLE_FOR_STRIKE);
   request.WriteString(family);
   request.WriteInt(sizeAndStyle);
 
   uint8_t buf[512];
-  const int sandbox_fd =
-    kSandboxIPCChannel + base::GlobalDescriptors::kBaseDescriptor;
-  const ssize_t n = base::SendRecvMsg(sandbox_fd, buf, sizeof(buf), NULL,
+  const ssize_t n = base::SendRecvMsg(GetSandboxFD(), buf, sizeof(buf), NULL,
                                       request);
 
   out->setDefaults();
   if (n == -1) {
     return;
   }
 
   Pickle reply(reinterpret_cast<char*>(buf), n);
   void* pickle_iter = NULL;
   int useBitmaps, useAutoHint, useHinting, hintStyle, useAntiAlias, useSubpixel;
   if (reply.ReadInt(&pickle_iter, &useBitmaps) &&
       reply.ReadInt(&pickle_iter, &useAutoHint) &&
       reply.ReadInt(&pickle_iter, &useHinting) &&
       reply.ReadInt(&pickle_iter, &hintStyle) &&
       reply.ReadInt(&pickle_iter, &useAntiAlias) &&
       reply.ReadInt(&pickle_iter, &useSubpixel)) {
     out->useBitmaps = useBitmaps;
     out->useAutoHint = useAutoHint;
     out->useHinting = useHinting;
     out->hintStyle = hintStyle;
     out->useAntiAlias = useAntiAlias;
     out->useSubpixel = useSubpixel;
   }
 }
 
+int MakeSharedMemorySegmentViaIPC(size_t length) {
+  Pickle request;
+  request.WriteInt(LinuxSandbox::METHOD_MAKE_SHARED_MEMORY_SEGMENT);
+  request.WriteUInt32(length);
+  uint8_t reply_buf[10];
+  int result_fd;
+  ssize_t result = base::SendRecvMsg(GetSandboxFD(),
+                                     reply_buf, sizeof(reply_buf),
+                                     &result_fd, request);
+  if (result == -1)
+    return -1;
+  return result_fd;
+}
+
 }  // namespace render_sandbox_support