// Copyright (c) 2012 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 "content/common/child_process_sandbox_support_impl_linux.h" #include #include #include "base/basictypes.h" #include "base/memory/scoped_ptr.h" #include "base/numerics/safe_conversions.h" #include "base/pickle.h" #include "base/posix/eintr_wrapper.h" #include "base/posix/unix_domain_socket_linux.h" #include "base/sys_byteorder.h" #include "base/trace_event/trace_event.h" #include "content/common/sandbox_linux/sandbox_linux.h" #include "third_party/WebKit/public/platform/linux/WebFallbackFont.h" #include "third_party/WebKit/public/platform/linux/WebFontRenderStyle.h" namespace content { void GetFallbackFontForCharacter(int32_t character, const char* preferred_locale, blink::WebFallbackFont* fallbackFont) { TRACE_EVENT0("sandbox_ipc", "GetFontFamilyForCharacter"); Pickle request; request.WriteInt(LinuxSandbox::METHOD_GET_FALLBACK_FONT_FOR_CHAR); request.WriteInt(character); request.WriteString(preferred_locale); uint8_t buf[512]; const ssize_t n = UnixDomainSocket::SendRecvMsg(GetSandboxFD(), buf, sizeof(buf), NULL, request); std::string family_name; std::string filename; int fontconfigInterfaceId = 0; int ttcIndex = 0; bool isBold = false; bool isItalic = false; if (n != -1) { Pickle reply(reinterpret_cast(buf), n); PickleIterator pickle_iter(reply); if (pickle_iter.ReadString(&family_name) && pickle_iter.ReadString(&filename) && pickle_iter.ReadInt(&fontconfigInterfaceId) && pickle_iter.ReadInt(&ttcIndex) && pickle_iter.ReadBool(&isBold) && pickle_iter.ReadBool(&isItalic)) { fallbackFont->name = family_name; fallbackFont->filename = filename; fallbackFont->fontconfigInterfaceId = fontconfigInterfaceId; fallbackFont->ttcIndex = ttcIndex; fallbackFont->isBold = isBold; fallbackFont->isItalic = isItalic; } } } void GetRenderStyleForStrike(const char* family, int size_and_style, blink::WebFontRenderStyle* out) { TRACE_EVENT0("sandbox_ipc", "GetRenderStyleForStrike"); out->setDefaults(); if (size_and_style < 0) return; const bool bold = size_and_style & 1; const bool italic = size_and_style & 2; const int pixel_size = size_and_style >> 2; if (pixel_size > std::numeric_limits::max()) return; Pickle request; request.WriteInt(LinuxSandbox::METHOD_GET_STYLE_FOR_STRIKE); request.WriteString(family); request.WriteBool(bold); request.WriteBool(italic); request.WriteUInt16(pixel_size); uint8_t buf[512]; const ssize_t n = UnixDomainSocket::SendRecvMsg(GetSandboxFD(), buf, sizeof(buf), NULL, request); if (n == -1) return; Pickle reply(reinterpret_cast(buf), n); PickleIterator pickle_iter(reply); int use_bitmaps, use_autohint, use_hinting, hint_style, use_antialias; int use_subpixel_rendering, use_subpixel_positioning; if (pickle_iter.ReadInt(&use_bitmaps) && pickle_iter.ReadInt(&use_autohint) && pickle_iter.ReadInt(&use_hinting) && pickle_iter.ReadInt(&hint_style) && pickle_iter.ReadInt(&use_antialias) && pickle_iter.ReadInt(&use_subpixel_rendering) && pickle_iter.ReadInt(&use_subpixel_positioning)) { out->useBitmaps = use_bitmaps; out->useAutoHint = use_autohint; out->useHinting = use_hinting; out->hintStyle = hint_style; out->useAntiAlias = use_antialias; out->useSubpixelRendering = use_subpixel_rendering; out->useSubpixelPositioning = use_subpixel_positioning; } } int MatchFontWithFallback(const std::string& face, bool bold, bool italic, int charset, PP_BrowserFont_Trusted_Family fallback_family) { TRACE_EVENT0("sandbox_ipc", "MatchFontWithFallback"); Pickle request; request.WriteInt(LinuxSandbox::METHOD_MATCH_WITH_FALLBACK); request.WriteString(face); request.WriteBool(bold); request.WriteBool(italic); request.WriteUInt32(charset); request.WriteUInt32(fallback_family); uint8_t reply_buf[64]; int fd = -1; UnixDomainSocket::SendRecvMsg(GetSandboxFD(), reply_buf, sizeof(reply_buf), &fd, request); return fd; } bool GetFontTable(int fd, uint32_t table_tag, off_t offset, uint8_t* output, size_t* output_length) { if (offset < 0) return false; size_t data_length = 0; // the length of the file data. off_t data_offset = 0; // the offset of the data in the file. if (table_tag == 0) { // Get the entire font file. struct stat st; if (fstat(fd, &st) < 0) return false; data_length = base::checked_cast(st.st_size); } else { // Get a font table. Read the header to find its offset in the file. uint16_t num_tables; ssize_t n = HANDLE_EINTR(pread(fd, &num_tables, sizeof(num_tables), 4 /* skip the font type */)); if (n != sizeof(num_tables)) return false; // Font data is stored in net (big-endian) order. num_tables = base::NetToHost16(num_tables); // Read the table directory. static const size_t kTableEntrySize = 16; const size_t directory_size = num_tables * kTableEntrySize; scoped_ptr table_entries(new uint8_t[directory_size]); n = HANDLE_EINTR(pread(fd, table_entries.get(), directory_size, 12 /* skip the SFNT header */)); if (n != base::checked_cast(directory_size)) return false; for (uint16_t i = 0; i < num_tables; ++i) { uint8_t* entry = table_entries.get() + i * kTableEntrySize; uint32_t tag = *reinterpret_cast(entry); if (tag == table_tag) { // Font data is stored in net (big-endian) order. data_offset = base::NetToHost32(*reinterpret_cast(entry + 8)); data_length = base::NetToHost32(*reinterpret_cast(entry + 12)); break; } } } if (!data_length) return false; // Clamp |offset| inside the allowable range. This allows the read to succeed // but return 0 bytes. offset = std::min(offset, base::checked_cast(data_length)); // Make sure it's safe to add the data offset and the caller's logical offset. // Define the maximum positive offset on 32 bit systems. static const off_t kMaxPositiveOffset32 = 0x7FFFFFFF; // 2 GB - 1. if ((offset > kMaxPositiveOffset32 / 2) || (data_offset > kMaxPositiveOffset32 / 2)) return false; data_offset += offset; data_length -= offset; if (output) { // 'output_length' holds the maximum amount of data the caller can accept. data_length = std::min(data_length, *output_length); ssize_t n = HANDLE_EINTR(pread(fd, output, data_length, data_offset)); if (n != base::checked_cast(data_length)) return false; } *output_length = data_length; return true; } } // namespace content