content/common/child_process_sandbox_support_impl_linux.cc

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/common/child_process_sandbox_support_impl_linux.h"
   6
   7 #include <sys/stat.h>
   8
   9 #include "base/eintr_wrapper.h"
  10 #include "base/global_descriptors_posix.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/pickle.h"
  13 #include "content/common/chrome_descriptors.h"
  14 #include "content/common/sandbox_methods_linux.h"
  15 #include "content/common/unix_domain_socket_posix.h"
  16 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/linux/WebFontFamily.h"
  17 #include "third_party/WebKit/Source/WebKit/chromium/public/linux/WebFontRenderStyle.h"
  18
  19 static int GetSandboxFD() {
  20   return kSandboxIPCChannel + base::GlobalDescriptors::kBaseDescriptor;
  21 }
  22
  23 namespace content {
  24
  25 void GetFontFamilyForCharacters(const uint16_t* utf16,
  26                                 size_t num_utf16,
  27                                 const char* preferred_locale,
  28                                 WebKit::WebFontFamily* family) {
  29   Pickle request;
  30   request.WriteInt(LinuxSandbox::METHOD_GET_FONT_FAMILY_FOR_CHARS);
  31   request.WriteInt(num_utf16);
  32   for (size_t i = 0; i < num_utf16; ++i)
  33     request.WriteUInt32(utf16[i]);
  34   request.WriteString(preferred_locale);
  35
  36   uint8_t buf[512];
  37   const ssize_t n = UnixDomainSocket::SendRecvMsg(GetSandboxFD(), buf,
  38                                                   sizeof(buf), NULL, request);
  39
  40   std::string family_name;
  41   bool isBold = false;
  42   bool isItalic = false;
  43   if (n != -1) {
  44     Pickle reply(reinterpret_cast<char*>(buf), n);
  45     void* pickle_iter = NULL;
  46     if (reply.ReadString(&pickle_iter, &family_name) &&
  47         reply.ReadBool(&pickle_iter, &isBold) &&
  48         reply.ReadBool(&pickle_iter, &isItalic)) {
  49       family->name = family_name;
  50       family->isBold = isBold;
  51       family->isItalic = isItalic;
  52     }
  53   }
  54 }
  55
  56 void GetRenderStyleForStrike(const char* family, int sizeAndStyle,
  57                              WebKit::WebFontRenderStyle* out) {
  58   Pickle request;
  59   request.WriteInt(LinuxSandbox::METHOD_GET_STYLE_FOR_STRIKE);
  60   request.WriteString(family);
  61   request.WriteInt(sizeAndStyle);
  62
  63   uint8_t buf[512];
  64   const ssize_t n = UnixDomainSocket::SendRecvMsg(GetSandboxFD(), buf,
  65                                                   sizeof(buf), NULL, request);
  66
  67   out->setDefaults();
  68   if (n == -1) {
  69     return;
  70   }
  71
  72   Pickle reply(reinterpret_cast<char*>(buf), n);
  73   void* pickle_iter = NULL;
  74   int useBitmaps, useAutoHint, useHinting, hintStyle, useAntiAlias, useSubpixel;
  75   if (reply.ReadInt(&pickle_iter, &useBitmaps) &&
  76       reply.ReadInt(&pickle_iter, &useAutoHint) &&
  77       reply.ReadInt(&pickle_iter, &useHinting) &&
  78       reply.ReadInt(&pickle_iter, &hintStyle) &&
  79       reply.ReadInt(&pickle_iter, &useAntiAlias) &&
  80       reply.ReadInt(&pickle_iter, &useSubpixel)) {
  81     out->useBitmaps = useBitmaps;
  82     out->useAutoHint = useAutoHint;
  83     out->useHinting = useHinting;
  84     out->hintStyle = hintStyle;
  85     out->useAntiAlias = useAntiAlias;
  86     out->useSubpixel = useSubpixel;
  87   }
  88 }
  89
  90 int MakeSharedMemorySegmentViaIPC(size_t length, bool executable) {
  91   Pickle request;
  92   request.WriteInt(LinuxSandbox::METHOD_MAKE_SHARED_MEMORY_SEGMENT);
  93   request.WriteUInt32(length);
  94   request.WriteBool(executable);
  95   uint8_t reply_buf[10];
  96   int result_fd;
  97   ssize_t result = UnixDomainSocket::SendRecvMsg(GetSandboxFD(),
  98                                                  reply_buf, sizeof(reply_buf),
  99                                                  &result_fd, request);
 100   if (result == -1)
 101     return -1;
 102   return result_fd;
 103 }
 104
 105 int MatchFontWithFallback(const std::string& face, bool bold,
 106                           bool italic, int charset) {
 107   Pickle request;
 108   request.WriteInt(LinuxSandbox::METHOD_MATCH_WITH_FALLBACK);
 109   request.WriteString(face);
 110   request.WriteBool(bold);
 111   request.WriteBool(italic);
 112   request.WriteUInt32(charset);
 113   uint8_t reply_buf[64];
 114   int fd = -1;
 115   UnixDomainSocket::SendRecvMsg(GetSandboxFD(), reply_buf, sizeof(reply_buf),
 116                                 &fd, request);
 117   return fd;
 118 }
 119
 120 bool GetFontTable(int fd, uint32_t table, uint8_t* output,
 121                   size_t* output_length) {
 122   if (table == 0) {
 123     struct stat st;
 124     if (fstat(fd, &st) < 0)
 125       return false;
 126     size_t length = st.st_size;
 127     if (!output) {
 128       *output_length = length;
 129       return true;
 130     }
 131     if (*output_length < length)
 132       return false;
 133     *output_length = length;
 134     ssize_t n = HANDLE_EINTR(pread(fd, output, length, 0));
 135     if (n != static_cast<ssize_t>(length))
 136       return false;
 137     return true;
 138   }
 139
 140   unsigned num_tables;
 141   uint8_t num_tables_buf[2];
 142
 143   ssize_t n = HANDLE_EINTR(pread(fd, &num_tables_buf, sizeof(num_tables_buf),
 144                            4 /* skip the font type */));
 145   if (n != sizeof(num_tables_buf))
 146     return false;
 147
 148   num_tables = static_cast<unsigned>(num_tables_buf[0]) << 8 |
 149                num_tables_buf[1];
 150
 151   // The size in bytes of an entry in the table directory.
 152   static const unsigned kTableEntrySize = 16;
 153   scoped_array<uint8_t> table_entries(
 154       new uint8_t[num_tables * kTableEntrySize]);
 155   n = HANDLE_EINTR(pread(fd, table_entries.get(), num_tables * kTableEntrySize,
 156                          12 /* skip the SFNT header */));
 157   if (n != static_cast<ssize_t>(num_tables * kTableEntrySize))
 158     return false;
 159
 160   size_t offset;
 161   size_t length = 0;
 162   for (unsigned i = 0; i < num_tables; i++) {
 163     const uint8_t* entry = table_entries.get() + i * kTableEntrySize;
 164     if (memcmp(entry, &table, sizeof(table)) == 0) {
 165       offset = static_cast<size_t>(entry[8]) << 24 |
 166                static_cast<size_t>(entry[9]) << 16 |
 167                static_cast<size_t>(entry[10]) << 8  |
 168                static_cast<size_t>(entry[11]);
 169       length = static_cast<size_t>(entry[12]) << 24 |
 170                static_cast<size_t>(entry[13]) << 16 |
 171                static_cast<size_t>(entry[14]) << 8  |
 172                static_cast<size_t>(entry[15]);
 173
 174       break;
 175     }
 176   }
 177
 178   if (!length)
 179     return false;
 180
 181   if (!output) {
 182     *output_length = length;
 183     return true;
 184   }
 185
 186   if (*output_length < length)
 187     return false;
 188
 189   *output_length = length;
 190   n = HANDLE_EINTR(pread(fd, output, length, offset));
 191   if (n != static_cast<ssize_t>(length))
 192     return false;
 193
 194   return true;
 195 }
 196
 197 }  // namespace content