/* Wait up to a minute for an in-coming connection.
*
* @param sd The listening socket or -1.
* @retval > 0 In-coming connection.
* @retval 0 No in-coming connection.
* @retval -1 Error (other than interrupt).
* @retval < -1 Interrupted while waiting.
*/
static int WaitForIncoming(int sd)
{
Log(LOG_LEVEL_DEBUG, "Waiting at incoming select...");
struct timeval timeout = { .tv_sec = 60 };
int signal_pipe = GetSignalPipe();
fd_set rset;
FD_ZERO(&rset);
FD_SET(signal_pipe, &rset);
/* sd might be -1 if "listen" attribute in body server control is set
* to off (enterprise feature for call-collected clients). */
if (sd != -1)
{
FD_SET(sd, &rset);
}
int result = select(MAX(sd, signal_pipe) + 1,
&rset, NULL, NULL, &timeout);
if (result == -1)
{
return (errno == EINTR) ? -2 : -1;
}
assert(result >= 0);
/* Empty the signal pipe, it is there to only detect missed
* signals in-between checking IsPendingTermination() and calling
* select(). */
unsigned char buf;
while (recv(signal_pipe, &buf, 1, 0) > 0)
{
/* skip */
}
/* We have an incoming connection if select() marked sd as ready: */
if (sd != -1 && result > 0 && FD_ISSET(sd, &rset))
{
return 1;
}
return 0;
}
/* Check for new policy just before spawning a thread.
*
* Server reconfiguration can only happen when no threads are active,
* so this is a good time to do it; but we do still have to check for
* running threads. */
static void PolicyUpdateIfSafe(EvalContext *ctx, Policy **policy,
GenericAgentConfig *config)
{
if (ThreadLock(cft_server_children))
{
int prior = COLLECT_INTERVAL;
if (ACTIVE_THREADS == 0)
{
CheckFileChanges(ctx, policy, config);
}
ThreadUnlock(cft_server_children);
/* Check for change in call-collect interval: */
if (prior != COLLECT_INTERVAL)
{
/* Start, stop or change schedule, as appropriate. */
CollectCallStart(COLLECT_INTERVAL);
}
}
}
/* Try to accept a connection; handle if we get one. */
static void AcceptAndHandle(EvalContext *ctx, int sd)
{
/* TODO embed ConnectionInfo into ServerConnectionState. */
ConnectionInfo *info = ConnectionInfoNew(); /* Uses xcalloc() */
info->ss_len = sizeof(info->ss);
info->sd = accept(sd, (struct sockaddr *) &info->ss, &info->ss_len);
if (info->sd == -1)
{
Log(LOG_LEVEL_INFO, "Error accepting connection (%s)", GetErrorStr());
ConnectionInfoDestroy(&info);
return;
}
Log(LOG_LEVEL_DEBUG, "Socket descriptor returned from accept(): %d",
info->sd);
/* Just convert IP address to string, no DNS lookup. */
char ipaddr[CF_MAX_IP_LEN] = "";
getnameinfo((const struct sockaddr *) &info->ss, info->ss_len,
ipaddr, sizeof(ipaddr),
NULL, 0, NI_NUMERICHOST);
/* IPv4 mapped addresses (e.g. "::ffff:192.168.1.2") are
* hereby represented with their IPv4 counterpart. */
ServerEntryPoint(ctx, MapAddress(ipaddr), info);
}
/**
* @retval >0 Number of threads still working
* @retval 0 All threads are done
* @retval -1 Server didn't run
*/
int StartServer(EvalContext *ctx, Policy **policy, GenericAgentConfig *config)
{
InitSignals();
ServerTLSInitialize();
int sd = SetServerListenState(ctx, QUEUESIZE, SERVER_LISTEN, &InitServer);
/* Necessary for our use of select() to work in WaitForIncoming(): */
assert(sd < sizeof(fd_set) * CHAR_BIT &&
GetSignalPipe() < sizeof(fd_set) * CHAR_BIT);
Policy *server_cfengine_policy = PolicyNew();
CfLock thislock = AcquireServerLock(ctx, config, server_cfengine_policy);
if (thislock.lock == NULL)
{
PolicyDestroy(server_cfengine_policy);
if (sd >= 0)
{
cf_closesocket(sd);
}
return -1;
}
PrepareServer(sd);
CollectCallStart(COLLECT_INTERVAL);
while (!IsPendingTermination())
{
CollectCallIfDue(ctx);
int selected = WaitForIncoming(sd);
Log(LOG_LEVEL_DEBUG, "select(): %d", selected);
if (selected == -1)
{
Log(LOG_LEVEL_ERR,
"Error while waiting for connections. (select: %s)",
GetErrorStr());
break;
}
else if (selected >= 0) /* timeout or success */
{
PolicyUpdateIfSafe(ctx, policy, config);
/* Is there a new connection pending at our listening socket? */
if (selected > 0)
{
AcceptAndHandle(ctx, sd);
}
} /* else: interrupted, maybe pending termination. */
}
Log(LOG_LEVEL_NOTICE, "Cleaning up and exiting...");
CollectCallStop();
if (sd != -1)
{
Log(LOG_LEVEL_VERBOSE, "Closing listening socket");
cf_closesocket(sd); /* Close listening socket */
}
/* This is a graceful exit, give 2 seconds chance to threads. */
int threads_left = WaitOnThreads();
YieldCurrentLock(thislock);
PolicyDestroy(server_cfengine_policy);
return threads_left;
}
void StartServer(EvalContext *ctx, Policy **policy, GenericAgentConfig *config)
{
int sd = -1;
fd_set rset;
int ret_val;
CfLock thislock;
time_t last_policy_reload = 0;
extern int COLLECT_WINDOW;
struct sockaddr_storage cin;
socklen_t addrlen = sizeof(cin);
MakeSignalPipe();
signal(SIGINT, HandleSignalsForDaemon);
signal(SIGTERM, HandleSignalsForDaemon);
signal(SIGHUP, SIG_IGN);
signal(SIGPIPE, SIG_IGN);
signal(SIGUSR1, HandleSignalsForDaemon);
signal(SIGUSR2, HandleSignalsForDaemon);
ServerTLSInitialize();
sd = SetServerListenState(ctx, QUEUESIZE, SERVER_LISTEN, &InitServer);
TransactionContext tc = {
.ifelapsed = 0,
.expireafter = 1,
};
Policy *server_cfengine_policy = PolicyNew();
Promise *pp = NULL;
{
Bundle *bp = PolicyAppendBundle(server_cfengine_policy, NamespaceDefault(), "server_cfengine_bundle", "agent", NULL, NULL);
PromiseType *tp = BundleAppendPromiseType(bp, "server_cfengine");
pp = PromiseTypeAppendPromise(tp, config->input_file, (Rval) { NULL, RVAL_TYPE_NOPROMISEE }, NULL);
}
assert(pp);
thislock = AcquireLock(ctx, pp->promiser, VUQNAME, CFSTARTTIME, tc, pp, false);
if (thislock.lock == NULL)
{
PolicyDestroy(server_cfengine_policy);
return;
}
if (sd != -1)
{
Log(LOG_LEVEL_VERBOSE, "Listening for connections ...");
}
#ifdef __MINGW32__
if (!NO_FORK)
{
Log(LOG_LEVEL_VERBOSE, "Windows does not support starting processes in the background - starting in foreground");
}
#else /* !__MINGW32__ */
if ((!NO_FORK) && (fork() != 0))
{
_exit(EXIT_SUCCESS);
}
if (!NO_FORK)
{
ActAsDaemon();
}
#endif /* !__MINGW32__ */
WritePID("cf-serverd.pid");
/* Andrew Stribblehill <*****@*****.**> -- close sd on exec */
#ifndef __MINGW32__
fcntl(sd, F_SETFD, FD_CLOEXEC);
#endif
CollectCallStart(COLLECT_INTERVAL);
while (!IsPendingTermination())
{
/* Note that this loop logic is single threaded, but ACTIVE_THREADS
might still change in threads pertaining to service handling */
if (ThreadLock(cft_server_children))
{
if (ACTIVE_THREADS == 0)
{
CheckFileChanges(ctx, policy, config, &last_policy_reload);
}
ThreadUnlock(cft_server_children);
}
// Check whether we have established peering with a hub
if (CollectCallHasPending())
{
int waiting_queue = 0;
int new_client = CollectCallGetPending(&waiting_queue);
if (waiting_queue > COLLECT_WINDOW)
{
Log(LOG_LEVEL_INFO, "Closing collect call because it would take"
"longer than the allocated window [%d]", COLLECT_WINDOW);
}
ConnectionInfo *info = ConnectionInfoNew();
if (info)
{
ConnectionInfoSetSocket(info, new_client);
ServerEntryPoint(ctx, POLICY_SERVER, info);
CollectCallMarkProcessed();
}
}
else
{
/* check if listening is working */
if (sd != -1)
{
// Look for normal incoming service requests
int signal_pipe = GetSignalPipe();
FD_ZERO(&rset);
FD_SET(sd, &rset);
FD_SET(signal_pipe, &rset);
Log(LOG_LEVEL_DEBUG, "Waiting at incoming select...");
struct timeval timeout = {
.tv_sec = 60,
.tv_usec = 0
};
int max_fd = (sd > signal_pipe) ? (sd + 1) : (signal_pipe + 1);
ret_val = select(max_fd, &rset, NULL, NULL, &timeout);
// Empty the signal pipe. We don't need the values.
unsigned char buf;
while (recv(signal_pipe, &buf, 1, 0) > 0) {}
if (ret_val == -1) /* Error received from call to select */
{
if (errno == EINTR)
{
continue;
}
else
{
Log(LOG_LEVEL_ERR, "select failed. (select: %s)", GetErrorStr());
exit(1);
}
}
else if (!ret_val) /* No data waiting, we must have timed out! */
{
continue;
}
if (FD_ISSET(sd, &rset))
{
int new_client = accept(sd, (struct sockaddr *)&cin, &addrlen);
if (new_client == -1)
{
continue;
}
/* Just convert IP address to string, no DNS lookup. */
char ipaddr[CF_MAX_IP_LEN] = "";
getnameinfo((struct sockaddr *) &cin, addrlen,
ipaddr, sizeof(ipaddr),
NULL, 0, NI_NUMERICHOST);
ConnectionInfo *info = ConnectionInfoNew();
if (info)
{
ConnectionInfoSetSocket(info, new_client);
ServerEntryPoint(ctx, ipaddr, info);
}
}
}
}
}
CollectCallStop();
PolicyDestroy(server_cfengine_policy);
}
/*********************************************************************/
/* Level 2 */
/*********************************************************************/
int InitServer(size_t queue_size)
{
int sd = -1;
if ((sd = OpenReceiverChannel()) == -1)
{
Log(LOG_LEVEL_ERR, "Unable to start server");
exit(EXIT_FAILURE);
}
if (listen(sd, queue_size) == -1)
{
Log(LOG_LEVEL_ERR, "listen failed. (listen: %s)", GetErrorStr());
exit(EXIT_FAILURE);
}
return sd;
}
