HRESULT CStunMessageBuilder::AddRandomTransactionId(StunTransactionId* pTransId)
{
StunTransactionId transid;
uint32_t stun_cookie_nbo = htonl(STUN_COOKIE);
uint32_t entropy=0;
// on x86, the rdtsc instruction is about as good as it gets for a random sequence number
// on linux, there's /dev/urandom
#ifdef _WIN32
// on windows, there's lots of simple stuff we can get at to give us a random number
// the rdtsc instruction is about as good as it gets
uint64_t clock = __rdtsc();
entropy ^= (uint32_t)(clock);
#else
// on linux, /dev/urandom should be sufficient
{
int randomfile = ::open("/dev/urandom", O_RDONLY);
if (randomfile >= 0)
{
int readret = read(randomfile, &entropy, sizeof(entropy));
UNREFERENCED_VARIABLE(readret);
ASSERT(readret > 0);
close(randomfile);
}
}
if (entropy == 0)
{
entropy ^= getpid();
entropy ^= reinterpret_cast<uintptr_t>(this);
entropy ^= time(NULL);
entropy ^= AtomicIncrement(&g_sequence_number);
}
#endif
srand(entropy);
// the first four bytes of the transaction id is always the magic cookie
// followed by 12 bytes of the real transaction id
memcpy(transid.id, &stun_cookie_nbo, sizeof(stun_cookie_nbo));
for (int x = 4; x < (STUN_TRANSACTION_ID_LENGTH-4); x++)
{
transid.id[x] = (uint8_t)(rand() % 256);
}
if (pTransId)
{
*pTransId = transid;
}
return AddTransactionId(transid);
}
HRESULT CStunMessageBuilder::AddMessageIntegrityLongTerm(const char* pszUserName, const char* pszRealm, const char* pszPassword)
{
HRESULT hr = S_OK;
const size_t MAX_KEY_SIZE = MAX_STUN_AUTH_STRING_SIZE*3 + 2;
uint8_t key[MAX_KEY_SIZE + 1]; // long enough for 64-char strings and two semicolons and a null char for debugging
uint8_t hash[MD5_DIGEST_LENGTH] = {};
uint8_t* pResult = NULL;
uint8_t* pDst = key;
size_t lenUserName = pszUserName ? strlen(pszUserName) : 0;
size_t lenRealm = pszRealm ? strlen(pszRealm) : 0;
size_t lenPassword = pszPassword ? strlen(pszPassword) : 0;
size_t lenTotal = lenUserName + lenRealm + lenPassword + 2; // +2 for the two colons
UNREFERENCED_VARIABLE(pResult);
ChkIfA(lenTotal > MAX_KEY_SIZE, E_INVALIDARG); // if we ever hit this limit, just increase MAX_STUN_AUTH_STRING_SIZE
// too bad CDatastream really only works on refcounted buffers. Otherwise, we wouldn't have to do all this messed up pointer math
// We could create a refcounted buffer in this function, but that would mean a call to "new and delete", and we're trying to avoid memory allocations in
// critical code paths because they are a proven perf hit
// TODO - Fix CDataStream and CBuffer so that "ref counted buffers" are no longer needed
pDst = key;
memcpy(pDst, pszUserName, lenUserName);
pDst += lenUserName;
*pDst = ':';
pDst++;
memcpy(pDst, pszRealm, lenRealm);
pDst += lenRealm;
*pDst = ':';
pDst++;
memcpy(pDst, pszPassword, lenPassword);
pDst += lenPassword;
*pDst ='\0'; // null terminate for debugging (this char doesn not get hashed
ASSERT((pDst-key) == lenTotal);
#ifndef __APPLE__
pResult = MD5(key, lenTotal, hash);
#else
pResult = CC_MD5(key, lenTotal, hash);
#endif
ASSERT(pResult != NULL);
hr= AddMessageIntegrityImpl(hash, MD5_DIGEST_LENGTH);
Cleanup:
return hr;
}
HRESULT CStunMessageBuilder::AddMessageIntegrityImpl(uint8_t* key, size_t keysize)
{
HRESULT hr = S_OK;
const size_t c_hmacsize = 20;
uint8_t hmacvaluedummy[c_hmacsize] = {}; // zero-init
unsigned int resultlength = c_hmacsize;
uint8_t* pDstBuf = NULL;
CRefCountedBuffer spBuffer;
void* pData = NULL;
size_t length = 0;
unsigned char* pHashResult = NULL;
UNREFERENCED_VARIABLE(pHashResult);
ChkIfA(key==NULL || keysize <= 0, E_INVALIDARG);
// add in a "zero-init" HMAC value. This adds 24 bytes to the length
Chk(AddAttribute(STUN_ATTRIBUTE_MESSAGEINTEGRITY, hmacvaluedummy, ARRAYSIZE(hmacvaluedummy)));
Chk(FixLengthField());
// now do a SHA1 on everything but the last 24 bytes (4 bytes of the attribute header and 20 bytes for the dummy content)
ChkA(_stream.GetBuffer(&spBuffer));
pData = spBuffer->GetData();
length = spBuffer->GetSize();
ASSERT(length > 24);
length = length-24;
// now do a little pointer math so that HMAC can write exactly to where the hash bytes will appear
pDstBuf = ((uint8_t*)pData) + length + 4;
#ifndef __APPLE__
pHashResult = HMAC(EVP_sha1(), key, keysize, (uint8_t*)pData, length, pDstBuf, &resultlength);
ASSERT(resultlength == 20);
ASSERT(pHashResult != NULL);
#else
CCHmac(kCCHmacAlgSHA1, key, keysize,(uint8_t*)pData, length, pDstBuf);
UNREFERENCED_VARIABLE(resultlength);
#endif
Cleanup:
return hr;
}
void CTestMessageHandler::ToAddr(const char* pszIP, uint16_t port, CSocketAddress* pAddr)
{
sockaddr_in addr={};
int result;
UNREFERENCED_VARIABLE(result);
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
result = ::inet_pton(AF_INET, pszIP, &addr.sin_addr);
ASSERT(result == 1);
*pAddr = addr;
}
// ----------------------------------------------------------------------------------------------
// this function must *always* return a valid Resource, even for 'missing' resources.
Resource* ResourceManager::LoadAsync(const WCHAR* filename, Resource* def)
{
AutoSync sync(&m_criticalSection); // CRITICAL SECTION - ENTIRE FUNCTION
Resource * res = NULL;
// check cache, use if already there.
if(NULL == res)
{
auto it = m_loaded.find(filename);
if(it != m_loaded.end() ) res = it->second;
}
// check pending, use if already there.
if(NULL == res)
{
auto it = m_pending.find(filename);
if(it != m_pending.end() ) res = it->second;
}
// create new info and add it to pending list to be loaded.
if(NULL == res)
{
ResourceFactory * factory = GetFactory(filename);
if (!factory)
{
return NULL;
}
res = factory->CreateResource(def);
m_pending[filename] = res;
BOOL success = SetEvent(m_EventHandle);
#ifdef NDEBUG
UNREFERENCED_VARIABLE(success);
#endif
assert(success);
}
assert(res);
res->AddRef();
return res;
}
// ----------------------------------------------------------------------------------------------
Resource* ColladaModelFactory::CreateResource(Resource* def)
{
UNREFERENCED_VARIABLE(def);
return new Model();
}
