/* * Copyright (c) 2002 - 2003 * NetGroup, Politecnico di Torino (Italy) * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the Politecnico di Torino nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ #ifdef HAVE_CONFIG_H #include #endif #ifdef _WIN32 #define USE_THREADS // threads vs. subprocesses #endif #include "ftmacros.h" #include // for the errno variable #include // for strtok, etc #include // for malloc(), free(), ... #include // for PCAP_ERRBUF_SIZE #include // for signal() #include #include "sockutils.h" // for socket calls #include "portability.h" #include "rpcapd.h" #include "fileconf.h" // for the configuration file management #include "rpcap-protocol.h" #include "pcap-rpcap-int.h" #include "daemon.h" // the true main() method of this daemon #include "utils.h" // Missing calls and such #ifdef _WIN32 #include "win32-svc.h" // for Win32 service stuff #else #include // for exit() #include // waitpid() #endif // Global variables char hostlist[MAX_HOST_LIST + 1]; //!< Keeps the list of the hosts that are allowed to connect to this server struct active_pars activelist[MAX_ACTIVE_LIST]; //!< Keeps the list of the hosts (host, port) on which I want to connect to (active mode) int nullAuthAllowed; //!< '1' if we permit NULL authentication, '0' otherwise static SOCKET sockmain; //!< keeps the main socket identifier char loadfile[MAX_LINE + 1]; //!< Name of the file from which we have to load the configuration int passivemode = 1; //!< '1' if we want to run in passive mode as well struct addrinfo mainhints; //!< temporary struct to keep settings needed to open the new socket char address[MAX_LINE + 1]; //!< keeps the network address (either numeric or literal) to bind to char port[MAX_LINE + 1]; //!< keeps the network port to bind to extern char *optarg; // for getopt() // Function definition static void main_passive(void *ptr); static void main_active(void *ptr); #ifndef _WIN32 static void main_cleanup_childs(int sign); #endif #define RPCAP_ACTIVE_WAIT 30 /* Waiting time between two attempts to open a connection, in active mode (default: 30 sec) */ /*! \brief Prints the usage screen if it is launched in console mode. */ static void printusage(void) { char *usagetext = "USAGE:\n" " " PROGRAM_NAME " [-b
] [-p ] [-6] [-l ] [-a ]\n" " [-n] [-v] [-d] [-s ] [-f ]\n" " -b
: the address to bind to (either numeric or literal).\n" " Default: it binds to all local IPv4 addresses\n" " -p : the port to bind to. Default: it binds to port " RPCAP_DEFAULT_NETPORT "\n" " -4: use only IPv4 (default both IPv4 and IPv6 waiting sockets are used)\n" " -l : a file that keeps the list of the hosts which are allowed\n" " to connect to this server (if more than one, list them one per line).\n" " We suggest to use literal names (instead of numeric ones) in order to\n" " avoid problems with different address families\n" " -n: permit NULL authentication (usually used with '-l')\n" " -a : run in active mode when connecting to 'host' on port 'port'\n" " In case 'port' is omitted, the default port (" RPCAP_DEFAULT_NETPORT_ACTIVE ") is used\n" " -v: run in active mode only (default: if '-a' is specified, it accepts\n" " passive connections as well\n" " -d: run in daemon mode (UNIX only) or as a service (Win32 only)\n" " Warning (Win32): this switch is provided automatically when the service\n" " is started from the control panel\n" " -s : save the current configuration to file\n" " -f : load the current configuration from file; all the switches\n" " specified from the command line are ignored\n" " -h: print this help screen\n\n"; printf("%s", usagetext); } //! Program main int main(int argc, char *argv[], char *envp[]) { char savefile[MAX_LINE + 1]; // name of the file on which we have to save the configuration int isdaemon = 0; // Not null if the user wants to run this program as a daemon int retval; // keeps the returning value from several functions char errbuf[PCAP_ERRBUF_SIZE + 1]; // keeps the error string, prior to be printed savefile[0] = 0; loadfile[0] = 0; hostlist[0] = 0; // Initialize errbuf memset(errbuf, 0, sizeof(errbuf)); if (sock_init(errbuf, PCAP_ERRBUF_SIZE) == -1) { SOCK_ASSERT(errbuf, 1); exit(-1); } strncpy(address, RPCAP_DEFAULT_NETADDR, MAX_LINE); strncpy(port, RPCAP_DEFAULT_NETPORT, MAX_LINE); // Prepare to open a new server socket memset(&mainhints, 0, sizeof(struct addrinfo)); mainhints.ai_family = PF_UNSPEC; mainhints.ai_flags = AI_PASSIVE; // Ready to a bind() socket mainhints.ai_socktype = SOCK_STREAM; // Getting the proper command line options while ((retval = getopt(argc, argv, "b:dhp:4l:na:s:f:v")) != -1) { switch (retval) { case 'b': strncpy(address, optarg, MAX_LINE); break; case 'p': strncpy(port, optarg, MAX_LINE); break; case '4': mainhints.ai_family = PF_INET; // IPv4 server only break; case 'd': isdaemon = 1; break; case 'n': nullAuthAllowed = 1; break; case 'v': passivemode = 0; break; case 'l': { strncpy(hostlist, optarg, sizeof(hostlist)); break; } case 'a': { char *tmpaddress, *tmpport; char *lasts; int i = 0; tmpaddress = pcap_strtok_r(optarg, RPCAP_HOSTLIST_SEP, &lasts); while ((tmpaddress != NULL) && (i < MAX_ACTIVE_LIST)) { tmpport = pcap_strtok_r(NULL, RPCAP_HOSTLIST_SEP, &lasts); strlcpy(activelist[i].address, tmpaddress, MAX_LINE); if ((tmpport == NULL) || (strcmp(tmpport, "DEFAULT") == 0)) // the user choose a custom port strlcpy(activelist[i].port, RPCAP_DEFAULT_NETPORT_ACTIVE, MAX_LINE); else strlcpy(activelist[i].port, tmpport, MAX_LINE); tmpaddress = pcap_strtok_r(NULL, RPCAP_HOSTLIST_SEP, &lasts); i++; } if (i > MAX_ACTIVE_LIST) SOCK_ASSERT("Only MAX_ACTIVE_LIST active connections are currently supported.", 1); // I don't initialize the remaining part of the structure, since // it is already zeroed (it is a global var) break; } case 'f': strlcpy(loadfile, optarg, MAX_LINE); break; case 's': strlcpy(savefile, optarg, MAX_LINE); break; case 'h': printusage(); exit(0); default: break; } } if (savefile[0]) { if (fileconf_save(savefile)) SOCK_ASSERT("Error when saving the configuration to file", 1); } // If the file does not exist, it keeps the settings provided by the command line if (loadfile[0]) fileconf_read(0); #ifndef _WIN32 // SIGTERM (i.e. kill -15) is not generated in Win32, although it is included for ANSI compatibility signal(SIGTERM, main_cleanup); signal(SIGCHLD, main_cleanup_childs); #endif // forking a daemon, if it is needed if (isdaemon) { #ifndef _WIN32 int pid; // Unix Network Programming, pg 336 if ((pid = fork()) != 0) exit(0); // Parent terminates // First child continues // Set daemon mode setsid(); // generated under unix with 'kill -HUP', needed to reload the configuration signal(SIGHUP, fileconf_read); if ((pid = fork()) != 0) exit(0); // First child terminates // LINUX WARNING: the current linux implementation of pthreads requires a management thread // to handle some hidden stuff. So, as soon as you create the first thread, two threads are // created. Fom this point on, the number of threads active are always one more compared // to the number you're expecting // Second child continues // umask(0); // chdir("/"); #else // We use the SIGABRT signal to kill the Win32 service signal(SIGABRT, main_cleanup); // If this call succeeds, it is blocking on Win32 if (svc_start() != 1) SOCK_ASSERT("Unable to start the service", 1); // When the previous call returns, the entire application has to be stopped. exit(0); #endif } else // Console mode { // Enable the catching of Ctrl+C signal(SIGINT, main_cleanup); #ifndef _WIN32 // generated under unix with 'kill -HUP', needed to reload the configuration // We do not have this kind of signal in Win32 signal(SIGHUP, fileconf_read); #endif printf("Press CTRL + C to stop the server...\n"); } // If we're a Win32 service, we have already called this function in the service_main main_startup(); // The code should never arrive here (since the main_startup is blocking) // however this avoids a compiler warning exit(0); } void main_startup(void) { char errbuf[PCAP_ERRBUF_SIZE + 1]; // keeps the error string, prior to be printed struct addrinfo *addrinfo; // keeps the addrinfo chain; required to open a new socket int i; #ifdef USE_THREADS pthread_t threadId; // Pthread variable that keeps the thread structures pthread_attr_t detachedAttribute; // PThread attribute needed to create the thread as detached #else pid_t pid; #endif i = 0; addrinfo = NULL; memset(errbuf, 0, sizeof(errbuf)); // Starts all the active threads while ((activelist[i].address[0] != 0) && (i < MAX_ACTIVE_LIST)) { activelist[i].ai_family = mainhints.ai_family; #ifdef USE_THREADS /* GV we need this to create the thread as detached. */ /* GV otherwise, the thread handle is not destroyed */ pthread_attr_init(&detachedAttribute); pthread_attr_setdetachstate(&detachedAttribute, PTHREAD_CREATE_DETACHED); if (pthread_create(&threadId, &detachedAttribute, (void *) &main_active, (void *) &activelist[i])) { SOCK_ASSERT("Error creating the active child thread", 1); pthread_attr_destroy(&detachedAttribute); continue; } pthread_attr_destroy(&detachedAttribute); #else if ((pid = fork()) == 0) // I am the child { main_active((void *) &activelist[i]); exit(0); } #endif i++; } /* * The code that manages the active connections is not blocking; * the code that manages the passive connection is blocking. * So, if the user does not want to run in passive mode, we have * to block the main thread here, otherwise the program ends and * all threads are stopped. * * WARNING: this means that in case we have only active mode, * the program does not terminate even if all the child thread * terminates. The user has always to press Ctrl+C (or send a * SIGTERM) to terminate the program. */ if (passivemode) { struct addrinfo *tempaddrinfo; // Do the work if (sock_initaddress((address[0]) ? address : NULL, port, &mainhints, &addrinfo, errbuf, PCAP_ERRBUF_SIZE) == -1) { SOCK_ASSERT(errbuf, 1); return; } tempaddrinfo = addrinfo; while (tempaddrinfo) { SOCKET *socktemp; if ((sockmain = sock_open(tempaddrinfo, SOCKOPEN_SERVER, SOCKET_MAXCONN, errbuf, PCAP_ERRBUF_SIZE)) == -1) { SOCK_ASSERT(errbuf, 1); tempaddrinfo = tempaddrinfo->ai_next; continue; } // This trick is needed in order to allow the child thread to save the 'sockmain' variable // withouth getting it overwritten by the sock_open, in case we want to open more than one waiting sockets // For instance, the pthread_create() will accept the socktemp variable, and it will deallocate immediately that variable socktemp = (SOCKET *) malloc (sizeof (SOCKET)); if (socktemp == NULL) exit(0); *socktemp = sockmain; #ifdef USE_THREADS /* GV we need this to create the thread as detached. */ /* GV otherwise, the thread handle is not destroyed */ pthread_attr_init(&detachedAttribute); pthread_attr_setdetachstate(&detachedAttribute, PTHREAD_CREATE_DETACHED); if (pthread_create(&threadId, &detachedAttribute, (void *) &main_passive, (void *) socktemp)) { SOCK_ASSERT("Error creating the passive child thread", 1); pthread_attr_destroy(&detachedAttribute); continue; } pthread_attr_destroy(&detachedAttribute); #else if ((pid = fork()) == 0) // I am the child { main_passive((void *) socktemp); return; } #endif tempaddrinfo = tempaddrinfo->ai_next; } freeaddrinfo(addrinfo); } // All the previous calls are no blocking, so the main line of execution goes here // and I have to avoid that the program terminates while (1) pthread_suspend(10*60*1000); // it wakes up every 10 minutes; it seems to me reasonable } /* \brief Closes gracefully (more or less) the program. This function is called: - when we're running in console - when we're running as a Win32 service (in case we press STOP) It is not called when we are running as a daemon on UNIX, since we do not define a signal in order to terminate gracefully the daemon. This function makes a fast cleanup (it does not clean everything, as you can see from the fact that it uses kill() on UNIX), closes the main socket, free winsock resources (on Win32) and exits the program. */ void main_cleanup(int sign) { #ifndef _WIN32 // Sends a KILL signal to all the processes // that share the same process group (i.e. kills all the childs) kill(0, SIGKILL); #endif SOCK_ASSERT(PROGRAM_NAME " is closing.\n", 1); // FULVIO (bug) // Here we close only the latest 'sockmain' created; if we opened more than one waiting sockets, // only the latest one is closed correctly. if (sockmain) closesocket(sockmain); sock_cleanup(); /* This code is executed under the following conditions: - SIGTERM: we're under UNIX, and the user kills us with 'kill -15' (no matter is we're a daemon or in a console mode) - SIGINT: we're in console mode and the user sends us a Ctrl+C (SIGINT signal), no matter if we're UNIX or Win32 In all these cases, we have to terminate the program. The case that still remains is if we're a Win32 service: in this case, we're a child thread, and we want just to terminate ourself. This is because the exit(0) will be invoked by the main thread, which is blocked waiting that all childs terminates. We are forced to call exit from the main thread otherwise the Win32 service control manager (SCM) does not work well. */ if ((sign == SIGTERM) || (sign == SIGINT)) exit(0); else return; } #ifndef _WIN32 static void main_cleanup_childs(int sign) { pid_t pid; int stat; // For reference, Stevens, pg 128 while ((pid = waitpid(-1, &stat, WNOHANG)) > 0) SOCK_ASSERT("Child terminated", 1); return; } #endif /*! \brief 'true' main of the program. It must be in a separate function because: - if we're in 'console' mode, we have to put the main thread waiting for a Ctrl+C (in order to be able to stop everything) - if we're in daemon mode, the main program must terminate and a new child must be created in order to create the daemon \param ptr: it keeps the main socket handler (what's called 'sockmain' in the main()), that represents the socket used in the main connection. It is a 'void *' just because pthreads want this format. */ static void main_passive(void *ptr) { char errbuf[PCAP_ERRBUF_SIZE + 1]; // keeps the error string, prior to be printed SOCKET sockctrl; // keeps the socket ID for this control connection struct sockaddr_storage from; // generic sockaddr_storage variable socklen_t fromlen; // keeps the length of the sockaddr_storage variable SOCKET sockmain; #ifndef USE_THREADS pid_t pid; #endif sockmain = *((SOCKET *) ptr); // Delete the pointer (which has been allocated in the main) free(ptr); // Initialize errbuf memset(errbuf, 0, sizeof(errbuf)); // main thread loop while (1) { #ifdef USE_THREADS pthread_t threadId; // Pthread variable that keeps the thread structures pthread_attr_t detachedAttribute; #endif struct daemon_slpars *pars; // parameters needed by the daemon_serviceloop() // Connection creation fromlen = sizeof(struct sockaddr_storage); sockctrl = accept(sockmain, (struct sockaddr *) &from, &fromlen); if (sockctrl == -1) { // The accept() call can return this error when a signal is catched // In this case, we have simply to ignore this error code // Stevens, pg 124 #ifdef _WIN32 if (WSAGetLastError() == WSAEINTR) #else if (errno == EINTR) #endif continue; // Don't check for errors here, since the error can be due to the fact that the thread // has been killed sock_geterror("accept(): ", errbuf, PCAP_ERRBUF_SIZE); SOCK_ASSERT(errbuf, 1); continue; } // checks if the connecting host is among the ones allowed if (sock_check_hostlist(hostlist, RPCAP_HOSTLIST_SEP, &from, errbuf, PCAP_ERRBUF_SIZE) < 0) { rpcap_senderror(sockctrl, errbuf, PCAP_ERR_HOSTNOAUTH, NULL); sock_close(sockctrl, NULL, 0); continue; } #ifdef USE_THREADS // in case of passive mode, this variable is deallocated by the daemon_serviceloop() pars = (struct daemon_slpars *) malloc (sizeof(struct daemon_slpars)); if (pars == NULL) { snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc() failed: %s", pcap_strerror(errno)); continue; } pars->sockctrl = sockctrl; pars->activeclose = 0; // useless in passive mode pars->isactive = 0; pars->nullAuthAllowed = nullAuthAllowed; /* GV we need this to create the thread as detached. */ /* GV otherwise, the thread handle is not destroyed */ pthread_attr_init(&detachedAttribute); pthread_attr_setdetachstate(&detachedAttribute, PTHREAD_CREATE_DETACHED); if (pthread_create(&threadId, &detachedAttribute, (void *) &daemon_serviceloop, (void *) pars)) { SOCK_ASSERT("Error creating the child thread", 1); pthread_attr_destroy(&detachedAttribute); continue; } pthread_attr_destroy(&detachedAttribute); #else if ((pid = fork()) == 0) // I am the child { // in case of passive mode, this variable is deallocated by the daemon_serviceloop() pars = (struct daemon_slpars *) malloc (sizeof(struct daemon_slpars)); if (pars == NULL) { snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc() failed: %s", pcap_strerror(errno)); exit(0); } pars->sockctrl = sockctrl; pars->activeclose = 0; // useless in passive mode pars->isactive = 0; pars->nullAuthAllowed = nullAuthAllowed; // Close the main socket (must be open only in the parent) closesocket(sockmain); daemon_serviceloop((void *) pars); exit(0); } // I am the parent // Close the childsocket (must be open only in the child) closesocket(sockctrl); #endif // loop forever, until interrupted } } /*! \brief 'true' main of the program in case the active mode is turned on. It does not have any return value nor parameters. This function loops forever trying to connect to the remote host, until the daemon is turned down. \param ptr: it keeps the 'activepars' parameters. It is a 'void *' just because pthreads want this format. */ static void main_active(void *ptr) { char errbuf[PCAP_ERRBUF_SIZE + 1]; // keeps the error string, prior to be printed SOCKET sockctrl; // keeps the socket ID for this control connection struct addrinfo hints; // temporary struct to keep settings needed to open the new socket struct addrinfo *addrinfo; // keeps the addrinfo chain; required to open a new socket struct active_pars *activepars; struct daemon_slpars *pars; // parameters needed by the daemon_serviceloop() activepars = (struct active_pars *) ptr; // Prepare to open a new server socket memset(&hints, 0, sizeof(struct addrinfo)); // WARNING Currently it supports only ONE socket family among IPv4 and IPv6 hints.ai_family = AF_INET; // PF_UNSPEC to have both IPv4 and IPv6 server hints.ai_socktype = SOCK_STREAM; hints.ai_family = activepars->ai_family; snprintf(errbuf, PCAP_ERRBUF_SIZE, "Connecting to host %s, port %s, using protocol %s", activepars->address, activepars->port, (hints.ai_family == AF_INET) ? "IPv4": (hints.ai_family == AF_INET6) ? "IPv6" : "Unspecified"); SOCK_ASSERT(errbuf, 1); // Initialize errbuf memset(errbuf, 0, sizeof(errbuf)); // Do the work if (sock_initaddress(activepars->address, activepars->port, &hints, &addrinfo, errbuf, PCAP_ERRBUF_SIZE) == -1) { SOCK_ASSERT(errbuf, 1); return; } while (1) { int activeclose; if ((sockctrl = sock_open(addrinfo, SOCKOPEN_CLIENT, 0, errbuf, PCAP_ERRBUF_SIZE)) == -1) { SOCK_ASSERT(errbuf, 1); snprintf(errbuf, PCAP_ERRBUF_SIZE, "Error connecting to host %s, port %s, using protocol %s", activepars->address, activepars->port, (hints.ai_family == AF_INET) ? "IPv4": (hints.ai_family == AF_INET6) ? "IPv6" : "Unspecified"); SOCK_ASSERT(errbuf, 1); pthread_suspend(RPCAP_ACTIVE_WAIT * 1000); continue; } pars = (struct daemon_slpars *) malloc (sizeof(struct daemon_slpars)); if (pars == NULL) { snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc() failed: %s", pcap_strerror(errno)); continue; } pars->sockctrl = sockctrl; pars->activeclose = 0; pars->isactive = 1; pars->nullAuthAllowed = nullAuthAllowed; daemon_serviceloop((void *) pars); activeclose = pars->activeclose; free(pars); // If the connection is closed by the user explicitely, don't try to connect to it again // just exit the program if (activeclose == 1) break; } }