1 : /* -*- Mode: C++; tab-width: 50; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 : /* ***** BEGIN LICENSE BLOCK *****
3 : * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4 : *
5 : * The contents of this file are subject to the Mozilla Public License Version
6 : * 1.1 (the "License"); you may not use this file except in compliance with
7 : * the License. You may obtain a copy of the License at
8 : * http://www.mozilla.org/MPL/
9 : *
10 : * Software distributed under the License is distributed on an "AS IS" basis,
11 : * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12 : * for the specific language governing rights and limitations under the
13 : * License.
14 : *
15 : * The Original Code is mozilla.org code.
16 : *
17 : * The Initial Developer of the Original Code is
18 : * mozilla.org
19 : * Portions created by the Initial Developer are Copyright (C) 2005
20 : * the Initial Developer. All Rights Reserved.
21 : *
22 : * Contributor(s):
23 : * Vladimir Vukicevic <vladimir@pobox.com> (original author)
24 : *
25 : * Alternatively, the contents of this file may be used under the terms of
26 : * either of the GNU General Public License Version 2 or later (the "GPL"),
27 : * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
28 : * in which case the provisions of the GPL or the LGPL are applicable instead
29 : * of those above. If you wish to allow use of your version of this file only
30 : * under the terms of either the GPL or the LGPL, and not to allow others to
31 : * use your version of this file under the terms of the MPL, indicate your
32 : * decision by deleting the provisions above and replace them with the notice
33 : * and other provisions required by the GPL or the LGPL. If you do not delete
34 : * the provisions above, a recipient may use your version of this file under
35 : * the terms of any one of the MPL, the GPL or the LGPL.
36 : *
37 : * ***** END LICENSE BLOCK ***** */
38 :
39 : #if defined(XP_WIN)
40 : #include <windows.h>
41 : #include <objbase.h>
42 : #elif defined(XP_MACOSX)
43 : #include <CoreFoundation/CoreFoundation.h>
44 : #else
45 : #include <stdlib.h>
46 : #include "prrng.h"
47 : #endif
48 :
49 : #include "nsMemory.h"
50 :
51 : #include "nsUUIDGenerator.h"
52 :
53 : using namespace mozilla;
54 :
55 32073 : NS_IMPL_THREADSAFE_ISUPPORTS1(nsUUIDGenerator, nsIUUIDGenerator)
56 :
57 1404 : nsUUIDGenerator::nsUUIDGenerator()
58 1404 : : mLock("nsUUIDGenerator.mLock")
59 : {
60 1404 : }
61 :
62 1404 : nsUUIDGenerator::~nsUUIDGenerator()
63 : {
64 1404 : }
65 :
66 : nsresult
67 1404 : nsUUIDGenerator::Init()
68 : {
69 : // We're a service, so we're guaranteed that Init() is not going
70 : // to be reentered while we're inside Init().
71 :
72 : #if !defined(XP_WIN) && !defined(XP_MACOSX) && !defined(ANDROID)
73 : /* initialize random number generator using NSPR random noise */
74 : unsigned int seed;
75 :
76 1404 : PRSize bytes = 0;
77 4212 : while (bytes < sizeof(seed)) {
78 1404 : PRSize nbytes = PR_GetRandomNoise(((unsigned char *)&seed)+bytes,
79 2808 : sizeof(seed)-bytes);
80 1404 : if (nbytes == 0) {
81 0 : return NS_ERROR_FAILURE;
82 : }
83 1404 : bytes += nbytes;
84 : }
85 :
86 : /* Initialize a new RNG state, and immediately switch
87 : * back to the previous one -- we want to use mState
88 : * only for our own calls to random().
89 : */
90 1404 : mSavedState = initstate(seed, mState, sizeof(mState));
91 1404 : setstate(mSavedState);
92 :
93 1404 : mRBytes = 4;
94 : #ifdef RAND_MAX
95 : if ((unsigned long) RAND_MAX < (unsigned long)0xffffffff)
96 1404 : mRBytes = 3;
97 : if ((unsigned long) RAND_MAX < (unsigned long)0x00ffffff)
98 : mRBytes = 2;
99 : if ((unsigned long) RAND_MAX < (unsigned long)0x0000ffff)
100 : mRBytes = 1;
101 : if ((unsigned long) RAND_MAX < (unsigned long)0x000000ff)
102 : return NS_ERROR_FAILURE;
103 : #endif
104 :
105 : #endif /* non XP_WIN and non XP_MACOSX */
106 :
107 1404 : return NS_OK;
108 : }
109 :
110 : NS_IMETHODIMP
111 1395 : nsUUIDGenerator::GenerateUUID(nsID** ret)
112 : {
113 1395 : nsID *id = static_cast<nsID*>(NS_Alloc(sizeof(nsID)));
114 1395 : if (id == nsnull)
115 0 : return NS_ERROR_OUT_OF_MEMORY;
116 :
117 1395 : nsresult rv = GenerateUUIDInPlace(id);
118 1395 : if (NS_FAILED(rv)) {
119 0 : NS_Free(id);
120 0 : return rv;
121 : }
122 :
123 1395 : *ret = id;
124 1395 : return rv;
125 : }
126 :
127 : NS_IMETHODIMP
128 5477 : nsUUIDGenerator::GenerateUUIDInPlace(nsID* id)
129 : {
130 : // The various code in this method is probably not threadsafe, so lock
131 : // across the whole method.
132 10954 : MutexAutoLock lock(mLock);
133 :
134 : #if defined(XP_WIN)
135 : HRESULT hr = CoCreateGuid((GUID*)id);
136 : if (NS_FAILED(hr))
137 : return NS_ERROR_FAILURE;
138 : #elif defined(XP_MACOSX)
139 : CFUUIDRef uuid = CFUUIDCreate(kCFAllocatorDefault);
140 : if (!uuid)
141 : return NS_ERROR_FAILURE;
142 :
143 : CFUUIDBytes bytes = CFUUIDGetUUIDBytes(uuid);
144 : memcpy(id, &bytes, sizeof(nsID));
145 :
146 : CFRelease(uuid);
147 : #else /* not windows or OS X; generate randomness using random(). */
148 : /* XXX we should be saving the return of setstate here and switching
149 : * back to it; instead, we use the value returned when we called
150 : * initstate, since older glibc's have broken setstate() return values
151 : */
152 : #ifndef ANDROID
153 5477 : setstate(mState);
154 : #endif
155 :
156 5477 : PRSize bytesLeft = sizeof(nsID);
157 43816 : while (bytesLeft > 0) {
158 : #ifdef ANDROID
159 : long rval = arc4random();
160 : const int mRBytes = 4;
161 : #else
162 32862 : long rval = random();
163 : #endif
164 :
165 :
166 32862 : PRUint8 *src = (PRUint8*)&rval;
167 : // We want to grab the mRBytes least significant bytes of rval, since
168 : // mRBytes less than sizeof(rval) means the high bytes are 0.
169 : #ifdef IS_BIG_ENDIAN
170 : src += sizeof(rval) - mRBytes;
171 : #endif
172 32862 : PRUint8 *dst = ((PRUint8*) id) + (sizeof(nsID) - bytesLeft);
173 32862 : PRSize toWrite = (bytesLeft < mRBytes ? bytesLeft : mRBytes);
174 120494 : for (PRSize i = 0; i < toWrite; i++)
175 87632 : dst[i] = src[i];
176 :
177 32862 : bytesLeft -= toWrite;
178 : }
179 :
180 : /* Put in the version */
181 5477 : id->m2 &= 0x0fff;
182 5477 : id->m2 |= 0x4000;
183 :
184 : /* Put in the variant */
185 5477 : id->m3[0] &= 0x3f;
186 5477 : id->m3[0] |= 0x80;
187 :
188 : #ifndef ANDROID
189 : /* Restore the previous RNG state */
190 5477 : setstate(mSavedState);
191 : #endif
192 : #endif
193 :
194 5477 : return NS_OK;
195 : }
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