1/*
2* Copyright (C) 2010 Google Inc. All rights reserved.
3*
4* Redistribution and use in source and binary forms, with or without
5* modification, are permitted provided that the following conditions are
6* met:
7*
8* * Redistributions of source code must retain the above copyright
9* notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include <wtf/UUID.h>
33
34#include <mutex>
35#include <wtf/CryptographicallyRandomNumber.h>
36#include <wtf/HexNumber.h>
37#include <wtf/text/StringBuilder.h>
38
39#if OS(DARWIN)
40#include <sys/sysctl.h>
41#endif
42
43namespace WTF {
44
45String createCanonicalUUIDString()
46{
47 unsigned randomData[4];
48 cryptographicallyRandomValues(reinterpret_cast<unsigned char*>(randomData), sizeof(randomData));
49
50 // Format as Version 4 UUID.
51 StringBuilder builder;
52 builder.reserveCapacity(36);
53 appendUnsignedAsHexFixedSize(randomData[0], builder, 8, Lowercase);
54 builder.append('-');
55 appendUnsignedAsHexFixedSize(randomData[1] >> 16, builder, 4, Lowercase);
56 builder.appendLiteral("-4");
57 appendUnsignedAsHexFixedSize(randomData[1] & 0x00000fff, builder, 3, Lowercase);
58 builder.append('-');
59 appendUnsignedAsHexFixedSize((randomData[2] >> 30) | 0x8, builder, 1, Lowercase);
60 appendUnsignedAsHexFixedSize((randomData[2] >> 16) & 0x00000fff, builder, 3, Lowercase);
61 builder.append('-');
62 appendUnsignedAsHexFixedSize(randomData[2] & 0x0000ffff, builder, 4, Lowercase);
63 appendUnsignedAsHexFixedSize(randomData[3], builder, 8, Lowercase);
64 return builder.toString();
65}
66
67String bootSessionUUIDString()
68{
69 static LazyNeverDestroyed<String> bootSessionUUID;
70#if OS(DARWIN)
71 static std::once_flag onceKey;
72 std::call_once(onceKey, [] {
73 size_t uuidLength = 37;
74 char uuid[uuidLength];
75 if (sysctlbyname("kern.bootsessionuuid", uuid, &uuidLength, nullptr, 0))
76 return;
77 bootSessionUUID.construct(static_cast<const char*>(uuid), uuidLength - 1);
78 });
79#endif
80 return bootSessionUUID;
81}
82
83} // namespace WTF
84