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// nonce.cpp
/* Copyright 2009 10gen Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "pch.h"
#include "nonce.h"
#include "../util/time_support.h"
extern int do_md5_test(void);
namespace mongo {
BOOST_STATIC_ASSERT( sizeof(nonce64) == 8 );
static Security security; // needs to be static so _initialized is preset to false (see initsafe below)
Security::Security() {
static int n;
massert( 10352 , "Security is a singleton class", ++n == 1);
init();
}
NOINLINE_DECL void Security::init() {
if( _initialized ) return;
_initialized = true;
#if defined(__linux__) || defined(__sunos__) || defined(__APPLE__)
_devrandom = new ifstream("/dev/urandom", ios::binary|ios::in);
massert( 10353 , "can't open dev/urandom", _devrandom->is_open() );
#elif defined(_WIN32)
srand(curTimeMicros()); // perhaps not relevant for rand_s but we might want elsewhere anyway
#else
srandomdev();
#endif
#ifndef NDEBUG
if ( do_md5_test() )
massert( 10354 , "md5 unit test fails", false);
#endif
}
nonce64 Security::__getNonce() {
dassert( _initialized );
nonce64 n;
#if defined(__linux__) || defined(__sunos__) || defined(__APPLE__)
_devrandom->read((char*)&n, sizeof(n));
massert(10355 , "devrandom failed", !_devrandom->fail());
#elif defined(_WIN32)
unsigned a=0, b=0;
assert( rand_s(&a) == 0 );
assert( rand_s(&b) == 0 );
n = (((unsigned long long)a)<<32) | b;
#else
n = (((unsigned long long)random())<<32) | random();
#endif
return n;
}
SimpleMutex nonceMutex("nonce");
nonce64 Security::_getNonce() {
// not good this is a static as gcc will mutex protect it which costs time
SimpleMutex::scoped_lock lk(nonceMutex);
if( !_initialized )
init();
return __getNonce();
}
nonce64 Security::getNonceDuringInit() {
// the mutex might not be inited yet. init phase should be one thread anyway (hopefully we don't spawn threads therein)
if( !security._initialized )
security.init();
return security.__getNonce();
}
nonce64 Security::getNonce() {
return security._getNonce();
}
// name warns us this might be a little slow (see code above)
unsigned goodRandomNumberSlow() { return (unsigned) Security::getNonce(); }
} // namespace mongo
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