1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
|
// 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 <sys/stat.h>
#include "base/debug/trace_event.h"
#include "base/memory/scoped_ptr.h"
#include "base/pickle.h"
#include "base/posix/eintr_wrapper.h"
#include "base/posix/unix_domain_socket_linux.h"
#include "base/safe_numerics.h"
#include "base/sys_byteorder.h"
#include "content/common/sandbox_linux.h"
#include "third_party/WebKit/public/platform/linux/WebFontFamily.h"
#include "third_party/WebKit/public/platform/linux/WebFontRenderStyle.h"
namespace content {
void GetFontFamilyForCharacter(int32_t character,
const char* preferred_locale,
WebKit::WebFontFamily* family) {
TRACE_EVENT0("sandbox_ipc", "GetFontFamilyForCharacter");
Pickle request;
request.WriteInt(LinuxSandbox::METHOD_GET_FONT_FAMILY_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;
bool isBold = false;
bool isItalic = false;
if (n != -1) {
Pickle reply(reinterpret_cast<char*>(buf), n);
PickleIterator pickle_iter(reply);
if (reply.ReadString(&pickle_iter, &family_name) &&
reply.ReadBool(&pickle_iter, &isBold) &&
reply.ReadBool(&pickle_iter, &isItalic)) {
family->name = family_name;
family->isBold = isBold;
family->isItalic = isItalic;
}
}
}
void GetRenderStyleForStrike(const char* family, int sizeAndStyle,
WebKit::WebFontRenderStyle* out) {
TRACE_EVENT0("sandbox_ipc", "GetRenderStyleForStrike");
Pickle request;
request.WriteInt(LinuxSandbox::METHOD_GET_STYLE_FOR_STRIKE);
request.WriteString(family);
request.WriteInt(sizeAndStyle);
uint8_t buf[512];
const ssize_t n = UnixDomainSocket::SendRecvMsg(GetSandboxFD(), buf,
sizeof(buf), NULL, request);
out->setDefaults();
if (n == -1) {
return;
}
Pickle reply(reinterpret_cast<char*>(buf), n);
PickleIterator pickle_iter(reply);
int useBitmaps, useAutoHint, useHinting, hintStyle, useAntiAlias;
int useSubpixelRendering, useSubpixelPositioning;
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, &useSubpixelRendering) &&
reply.ReadInt(&pickle_iter, &useSubpixelPositioning)) {
out->useBitmaps = useBitmaps;
out->useAutoHint = useAutoHint;
out->useHinting = useHinting;
out->hintStyle = hintStyle;
out->useAntiAlias = useAntiAlias;
out->useSubpixelRendering = useSubpixelRendering;
out->useSubpixelPositioning = useSubpixelPositioning;
}
}
int MatchFontWithFallback(const std::string& face, bool bold,
bool italic, int charset) {
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);
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_numeric_cast<size_t>(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<uint8_t[]> 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_numeric_cast<ssize_t>(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<uint32_t*>(entry);
if (tag == table_tag) {
// Font data is stored in net (big-endian) order.
data_offset =
base::NetToHost32(*reinterpret_cast<uint32_t*>(entry + 8));
data_length =
base::NetToHost32(*reinterpret_cast<uint32_t*>(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_numeric_cast<off_t>(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_numeric_cast<ssize_t>(data_length))
return false;
}
*output_length = data_length;
return true;
}
} // namespace content
|
