//
// Open a listener which will create new links when messages arrive and queue them appropriately.
// Listeners are inherently insecure, as an adversary could easily create many connections that are never closed.
//
static AthenaTransportLink *
_UDPOpenListener(AthenaTransportLinkModule *athenaTransportLinkModule, const char *linkName, struct sockaddr_in *destination, size_t mtu)
{
const char *derivedLinkName;
_UDPLinkData *linkData = _UDPLinkData_Create();
linkData->multiplexTable = parcHashCodeTable_Create(_connectionEquals, _connectionHashCode, NULL, _closeConnection);
assertNotNull(linkData->multiplexTable, "Could not create multiplex table for new listener");
linkData->link.myAddress = *destination;
linkData->link.myAddressLength = sizeof(struct sockaddr_in);
linkData->link.mtu = mtu;
linkData->fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (linkData->fd < 0) {
parcLog_Error(athenaTransportLinkModule_GetLogger(athenaTransportLinkModule),
"socket error (%s)", strerror(errno));
_UDPLinkData_Destroy(&linkData);
return NULL;
}
int result = _setSocketOptions(athenaTransportLinkModule, linkData->fd);
if (result) {
close(linkData->fd);
_UDPLinkData_Destroy(&linkData);
return NULL;
}
// Set non-blocking flag
int flags = fcntl(linkData->fd, F_GETFL, NULL);
if (flags < 0) {
parcLog_Error(athenaTransportLinkModule_GetLogger(athenaTransportLinkModule),
"fcntl failed to get non-blocking flag (%s)", strerror(errno));
close(linkData->fd);
_UDPLinkData_Destroy(&linkData);
return NULL;
}
result = fcntl(linkData->fd, F_SETFL, flags | O_NONBLOCK);
if (result) {
parcLog_Error(athenaTransportLinkModule_GetLogger(athenaTransportLinkModule),
"fcntl failed to set non-blocking flag (%s)", strerror(errno));
close(linkData->fd);
_UDPLinkData_Destroy(&linkData);
return NULL;
}
// bind to listen on requested address
result = bind(linkData->fd, (struct sockaddr *) &linkData->link.myAddress, linkData->link.myAddressLength);
if (result) {
parcLog_Error(athenaTransportLinkModule_GetLogger(athenaTransportLinkModule),
"bind error (%s)", strerror(errno));
close(linkData->fd);
_UDPLinkData_Destroy(&linkData);
return NULL;
}
derivedLinkName = _createNameFromLinkData(&linkData->link);
if (linkName == NULL) {
linkName = derivedLinkName;
}
// Listener doesn't require a send method. The receive method is used to establish new connections.
AthenaTransportLink *athenaTransportLink = athenaTransportLink_Create(linkName,
NULL,
_UDPReceiveListener,
_UDPClose);
if (athenaTransportLink == NULL) {
parcLog_Error(athenaTransportLink_GetLogger(athenaTransportLink),
"athenaTransportLink_Create failed");
parcMemory_Deallocate(&derivedLinkName);
close(linkData->fd);
_UDPLinkData_Destroy(&linkData);
return athenaTransportLink;
}
athenaTransportLink_SetPrivateData(athenaTransportLink, linkData);
athenaTransportLink_SetEventFd(athenaTransportLink, linkData->fd);
// Links established for listening are not used to route messages.
// They can be kept in a listener list that doesn't consume a linkId.
athenaTransportLink_SetRoutable(athenaTransportLink, false);
parcLog_Info(athenaTransportLink_GetLogger(athenaTransportLink),
"new listener established: Name=\"%s\" (%s)", linkName, derivedLinkName);
parcMemory_Deallocate(&derivedLinkName);
return athenaTransportLink;
}
//
// Open a listener which will create new links when messages arrive and queue them appropriately.
// Listeners are inherently insecure, as an adversary could easily create many connections that are never closed.
//
static AthenaTransportLink *
_ETHOpenListener(AthenaTransportLinkModule *athenaTransportLinkModule, const char *linkName, const char *device, struct ether_addr *source, size_t mtu)
{
const char *derivedLinkName;
_ETHLinkData *linkData = _ETHLinkData_Create();
linkData->multiplexTable = parcHashCodeTable_Create(_connectionEquals, _connectionHashCode, NULL, _closeConnection);
assertNotNull(linkData->multiplexTable, "Could not create multiplex table for new listener");
linkData->athenaEthernet = athenaEthernet_Create(athenaTransportLinkModule_GetLogger(athenaTransportLinkModule),
device, CCNX_ETHERTYPE);
if (linkData->athenaEthernet == NULL) {
_ETHLinkData_Destroy(&linkData);
return NULL;
}
// Use specified source MAC address, or default to device MAC
if (source) {
memcpy(&(linkData->link.myAddress), source, sizeof(struct ether_addr));
} else {
athenaEthernet_GetMAC(linkData->athenaEthernet, &(linkData->link.myAddress));
}
linkData->link.myAddressLength = ETHER_ADDR_LEN;
if (linkData->athenaEthernet == NULL) {
parcLog_Error(athenaTransportLinkModule_GetLogger(athenaTransportLinkModule),
"athenaEthernet_Create error");
_ETHLinkData_Destroy(&linkData);
return NULL;
}
derivedLinkName = _createNameFromLinkData(&linkData->link, true);
if (linkName == NULL) {
linkName = derivedLinkName;
}
// Listener doesn't require a send method. The receive method is used to establish new connections.
AthenaTransportLink *athenaTransportLink = athenaTransportLink_Create(linkName,
NULL,
_ETHReceiveListener,
_ETHClose);
if (athenaTransportLink == NULL) {
parcLog_Error(athenaTransportLink_GetLogger(athenaTransportLink),
"athenaTransportLink_Create failed");
parcMemory_Deallocate(&derivedLinkName);
_ETHLinkData_Destroy(&linkData);
return athenaTransportLink;
}
athenaTransportLink_SetPrivateData(athenaTransportLink, linkData);
athenaTransportLink_SetEventFd(athenaTransportLink, athenaEthernet_GetDescriptor(linkData->athenaEthernet));
// Links established for listening are not used to route messages.
// They can be kept in a listener list that doesn't consume a linkId.
athenaTransportLink_SetRoutable(athenaTransportLink, false);
parcLog_Info(athenaTransportLink_GetLogger(athenaTransportLink),
"new listener established: Name=\"%s\" (%s)", linkName, derivedLinkName);
parcMemory_Deallocate(&derivedLinkName);
return athenaTransportLink;
}