/* -*- Mode: C; tab-width: 4 -*-
*
* Copyright (c) 2015 Apple Inc. All rights reserved.
*
* dnsctl_server.c
* mDNSResponder
*
* XPC as an IPC mechanism to communicate with dnsctl. Open only to Apple OSX/iOS clients
*/
#include "xpc_services.h"
#include "dns_xpc.h"
#include "mDNSMacOSX.h" // KQueueLock/KQueueUnlock
#include "helper.h" // mDNSResponderHelper tests
#include <xpc/xpc.h>
// ***************************************************************************
// Globals
extern mDNS mDNSStorage;
static dispatch_queue_t dnsctlserver_queue = NULL;
// ***************************************************************************
mDNSlocal void handle_logging(mDNSu32 log_level)
{
KQueueLock();
switch (log_level)
{
case log_level1:
mDNS_LoggingEnabled = mDNS_PacketLoggingEnabled = 0;
LogMsg("USR1 Logging:[%s] USR2 Logging:[%s]", mDNS_LoggingEnabled ? "Enabled" : "Disabled", mDNS_PacketLoggingEnabled ? "Enabled" : "Disabled");
break;
case log_level2:
mDNS_LoggingEnabled = 1;
LogMsg("USR1 Logging %s", mDNS_LoggingEnabled ? "Enabled" : "Disabled");
break;
case log_level3:
mDNS_PacketLoggingEnabled = 1;
LogMsg("USR2 Logging %s", mDNS_PacketLoggingEnabled ? "Enabled" : "Disabled");
break;
case log_level4:
mDNS_LoggingEnabled = 1 ;
mDNS_PacketLoggingEnabled = 1;
LogMsg("USR1 Logging:%s USR2 Logging:%s", mDNS_LoggingEnabled ? "Enabled" : "Disabled", mDNS_PacketLoggingEnabled ? "Enabled" : "Disabled");
break;
default:
mDNS_LoggingEnabled = 0 ;
mDNS_PacketLoggingEnabled = 0;
break;
}
UpdateDebugState();
KQueueUnlock("LogLevel changed");
}
mDNSlocal void handle_stateinfo(mDNSu32 state_level)
{
KQueueLock();
switch (state_level)
{
case full_state:
INFOCallback();
break;
default:
INFOCallback();
break;
}
KQueueUnlock("StateInfo dumped");
}
mDNSlocal void handle_test_mode(mDNSu32 test_mode)
{
KQueueLock();
switch (test_mode)
{
case test_helper_ipc:
mDNSNotify("mDNSResponderHelperTest", "This is just a test message to mDNSResponderHelper. This is NOT an actual alert");
break;
case test_mDNS_log:
LogInfo("LogInfo: Should be logged at INFO level");
LogOperation("LogOperation: Should be logged at INFO level");
LogMsg("LogMsg: Should be logged at DEFAULT level");
LogSPS("LogSPS: Should be logged at INFO level");
break;
default:
LogMsg("Unidentified Test mode: Please add this test");
break;
}
KQueueUnlock("Test Msg to mDNSResponderHelper");
}
mDNSlocal void handle_terminate()
{
LogInfo("handle_terminate: Client terminated connection.");
}
mDNSlocal void handle_requests(xpc_object_t req)
{
mDNSu32 log_level, state_level, test_mode;
xpc_connection_t remote_conn = xpc_dictionary_get_remote_connection(req);
LogInfo("handle_requests: Handler for dnsctl requests");
xpc_object_t response = xpc_dictionary_create_reply(req);
// Return Success Status to the client (essentially ACKing the request)
if (response)
{
xpc_dictionary_set_uint64(response, kDNSDaemonReply, kDNSMsg_NoError);
xpc_connection_send_message(remote_conn, response);
xpc_release(response);
}
else
{
LogMsg("handle_requests: Response Dictionary could not be created");
return;
}
// switch here based on dictionary
// to handle various different requests like logging, INFO snapshot, etc..
if ((xpc_dictionary_get_uint64(req, kDNSLogLevel)))
{
log_level = (mDNSu32)(xpc_dictionary_get_uint64(req, kDNSLogLevel));
handle_logging(log_level);
}
else if ((xpc_dictionary_get_uint64(req, kDNSStateInfo)))
{
state_level = (mDNSu32)(xpc_dictionary_get_uint64(req, kDNSStateInfo));
handle_stateinfo(state_level);
}
else if ((xpc_dictionary_get_uint64(req, kmDNSResponderTests)))
{
test_mode = (mDNSu32)(xpc_dictionary_get_uint64(req, kmDNSResponderTests));
handle_test_mode(test_mode);
}
}
mDNSlocal void accept_client(xpc_connection_t conn)
{
uid_t c_euid;
int c_pid;
c_euid = xpc_connection_get_euid(conn);
c_pid = xpc_connection_get_pid(conn);
if (c_euid != 0 || !IsEntitled(conn, kDNSCTLService))
{
LogMsg("accept_client: Client PID[%d] is missing Entitlement or is NOT running as root!", c_pid);
xpc_connection_cancel(conn);
return;
}
xpc_retain(conn);
xpc_connection_set_target_queue(conn, dnsctlserver_queue);
xpc_connection_set_event_handler(conn, ^(xpc_object_t req_msg)
{
xpc_type_t type = xpc_get_type(req_msg);
if (type == XPC_TYPE_DICTIONARY)
{
handle_requests(req_msg);
}
else // We hit this case ONLY if Client Terminated Connection OR Crashed
{
LogInfo("accept_client: Client %p teared down the connection", (void *) conn);
handle_terminate();
xpc_release(conn);
}
});
xpc_connection_resume(conn);
}
mDNSexport void init_dnsctl_service(void)
{
xpc_connection_t dnsctl_listener = xpc_connection_create_mach_service(kDNSCTLService, NULL, XPC_CONNECTION_MACH_SERVICE_LISTENER);
if (!dnsctl_listener || xpc_get_type(dnsctl_listener) != XPC_TYPE_CONNECTION)
{
LogMsg("init_dnsctl_service: Error Creating XPC Listener for DNSCTL Server!");
return;
}
dnsctlserver_queue = dispatch_queue_create("com.apple.mDNSResponder.dnsctlserver_queue", NULL);
xpc_connection_set_event_handler(dnsctl_listener, ^(xpc_object_t eventmsg)
{
xpc_type_t type = xpc_get_type(eventmsg);
if (type == XPC_TYPE_CONNECTION)
{
LogInfo("init_dnsctl_service: New DNSCTL Client %p", eventmsg);
accept_client(eventmsg);
}
else if (type == XPC_TYPE_ERROR) // Ideally, we would never hit these cases
{
LogMsg("init_dnsctl_service: XPCError: %s", xpc_dictionary_get_string(eventmsg, XPC_ERROR_KEY_DESCRIPTION));
}
else
{
LogMsg("init_dnsctl_service: Unknown EventMsg type");
}
});
xpc_connection_resume(dnsctl_listener);
}