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openggsn/ggsn/ggsn.c

527 lines
15 KiB
C

/*
* OpenGGSN - Gateway GPRS Support Node
* Copyright (C) 2002, 2003, 2004 Mondru AB.
*
* The contents of this file may be used under the terms of the GNU
* General Public License Version 2, provided that the above copyright
* notice and this permission notice is included in all copies or
* substantial portions of the software.
*
*/
/* ggsn.c
*
*/
#ifdef __linux__
#define _GNU_SOURCE 1 /* strdup() prototype, broken arpa/inet.h */
#endif
#include "../config.h"
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif
#include <syslog.h>
#include <ctype.h>
#include <netdb.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <errno.h>
#include <time.h>
#include "tun.h"
#include "ippool.h"
#include "syserr.h"
#include "../gtp/pdp.h"
#include "../gtp/gtp.h"
#include "cmdline.h"
int maxfd = 0; /* For select() */
struct in_addr listen_;
struct in_addr netaddr, destaddr, net, mask; /* Network interface */
struct in_addr dns1, dns2; /* PCO DNS address */
char *ipup, *ipdown; /* Filename of scripts */
int debug; /* Print debug output */
struct ul255_t pco;
struct ul255_t qos;
struct ul255_t apn;
struct gsn_t *gsn; /* GSN instance */
struct tun_t *tun; /* TUN instance */
struct ippool_t *ippool; /* Pool of IP addresses */
/* Used to write process ID to file. Assume someone else will delete */
void log_pid(char *pidfile) {
FILE *file;
mode_t oldmask;
oldmask = umask(022);
file = fopen(pidfile, "w");
umask(oldmask);
if(!file) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to create process ID file: %s!", pidfile);
return;
}
fprintf(file, "%d\n", (int) getpid());
fclose(file);
}
#if defined(_sun__)
int daemon(int nochdir, int noclose) {
int fd;
switch (fork()) {
case -1:
return (-1);
case 0:
break;
default:
_exit(0);
}
if (setsid() == -1)
return (-1);
if (!nochdir) chdir("/");
if (!noclose && (fd = open("/dev/null", O_RDWR, 0)) != -1) {
dup2(fd, STDIN_FILENO);
dup2(fd, STDOUT_FILENO);
dup2(fd, STDERR_FILENO);
if (fd > 2) close (fd);
}
return (0);
}
#endif
int encaps_printf(void *p, void *packet, unsigned len)
{
int i;
if (debug) {
printf("The packet looks like this:\n");
for( i=0; i<len; i++) {
printf("%02x ", (unsigned char)*(char *)(packet+i));
if (!((i+1)%16)) printf("\n");
};
printf("\n");
}
return 0;
}
int delete_context(struct pdp_t *pdp) {
if (debug) printf("Deleting PDP context\n");
if (pdp->peer)
ippool_freeip(ippool, (struct ippoolm_t *) pdp->peer);
else
sys_err(LOG_ERR, __FILE__, __LINE__, 0, "Peer not defined!");
return 0;
}
int create_context_ind(struct pdp_t *pdp) {
struct in_addr addr;
struct ippoolm_t *member;
if (debug) printf("Received create PDP context request\n");
pdp->eua.l=0; /* TODO: Indicates dynamic IP */
/* ulcpy(&pdp->qos_neg, &pdp->qos_req, sizeof(pdp->qos_req.v)); */
memcpy(pdp->qos_neg0, pdp->qos_req0, sizeof(pdp->qos_req0));
memcpy(&pdp->pco_neg, &pco, sizeof(pdp->pco_neg));
memcpy(pdp->qos_neg.v, pdp->qos_req.v, pdp->qos_req.l); /* TODO */
pdp->qos_neg.l = pdp->qos_req.l;
if (pdp_euaton(&pdp->eua, &addr)) {
addr.s_addr = 0; /* Request dynamic */
}
if (ippool_newip(ippool, &member, &addr)) {
gtp_create_context_resp(gsn, pdp, GTPCAUSE_NO_RESOURCES);
return 0; /* Allready in use, or no more available */
}
pdp_ntoeua(&member->addr, &pdp->eua);
pdp->peer = member;
pdp->ipif = tun; /* TODO */
member->peer = pdp;
gtp_create_context_resp(gsn, pdp, GTPCAUSE_ACC_REQ);
return 0; /* Success */
}
/* Callback for receiving messages from tun */
int cb_tun_ind(struct tun_t *tun, void *pack, unsigned len) {
struct ippoolm_t *ipm;
struct in_addr dst;
struct tun_packet_t *iph = (struct tun_packet_t*) pack;
dst.s_addr = iph->dst;
if (debug) printf("Received packet from tun!\n");
if (ippool_getip(ippool, &ipm, &dst)) {
if (debug) printf("Received packet with no destination!!!\n");
return 0;
}
if (ipm->peer) /* Check if a peer protocol is defined */
gtp_data_req(gsn, (struct pdp_t*) ipm->peer, pack, len);
return 0;
}
int encaps_tun(struct pdp_t *pdp, void *pack, unsigned len) {
if (debug) printf("encaps_tun. Packet received: forwarding to tun\n");
return tun_encaps((struct tun_t*) pdp->ipif, pack, len);
}
int main(int argc, char **argv)
{
/* gengeopt declarations */
struct gengetopt_args_info args_info;
struct hostent *host;
fd_set fds; /* For select() */
struct timeval idleTime; /* How long to select() */
int timelimit; /* Number of seconds to be connected */
int starttime; /* Time program was started */
/* open a connection to the syslog daemon */
/*openlog(PACKAGE, LOG_PID, LOG_DAEMON);*/
/* TODO: Only use LOG__PERROR for linux */
#ifdef __linux__
openlog(PACKAGE, (LOG_PID | LOG_PERROR), LOG_DAEMON);
#else
openlog(PACKAGE, (LOG_PID), LOG_DAEMON);
#endif
if (cmdline_parser (argc, argv, &args_info) != 0)
exit(1);
if (args_info.debug_flag) {
printf("listen: %s\n", args_info.listen_arg);
if (args_info.conf_arg) printf("conf: %s\n", args_info.conf_arg);
printf("fg: %d\n", args_info.fg_flag);
printf("debug: %d\n", args_info.debug_flag);
printf("qos: %#08x\n", args_info.qos_arg);
if (args_info.apn_arg) printf("apn: %s\n", args_info.apn_arg);
if (args_info.net_arg) printf("net: %s\n", args_info.net_arg);
if (args_info.dynip_arg) printf("dynip: %s\n", args_info.dynip_arg);
if (args_info.statip_arg) printf("statip: %s\n", args_info.statip_arg);
if (args_info.ipup_arg) printf("ipup: %s\n", args_info.ipup_arg);
if (args_info.ipdown_arg) printf("ipdown: %s\n", args_info.ipdown_arg);
if (args_info.pidfile_arg) printf("pidfile: %s\n", args_info.pidfile_arg);
if (args_info.statedir_arg) printf("statedir: %s\n", args_info.statedir_arg);
printf("timelimit: %d\n", args_info.timelimit_arg);
}
/* Try out our new parser */
if (cmdline_parser_configfile (args_info.conf_arg, &args_info, 0) != 0)
exit(1);
if (args_info.debug_flag) {
printf("cmdline_parser_configfile\n");
printf("listen: %s\n", args_info.listen_arg);
printf("conf: %s\n", args_info.conf_arg);
printf("fg: %d\n", args_info.fg_flag);
printf("debug: %d\n", args_info.debug_flag);
printf("qos: %#08x\n", args_info.qos_arg);
if (args_info.apn_arg) printf("apn: %s\n", args_info.apn_arg);
if (args_info.net_arg) printf("net: %s\n", args_info.net_arg);
if (args_info.dynip_arg) printf("dynip: %s\n", args_info.dynip_arg);
if (args_info.statip_arg) printf("statip: %s\n", args_info.statip_arg);
if (args_info.ipup_arg) printf("ipup: %s\n", args_info.ipup_arg);
if (args_info.ipdown_arg) printf("ipdown: %s\n", args_info.ipdown_arg);
if (args_info.pidfile_arg) printf("pidfile: %s\n", args_info.pidfile_arg);
if (args_info.statedir_arg) printf("statedir: %s\n", args_info.statedir_arg);
printf("timelimit: %d\n", args_info.timelimit_arg);
}
/* Handle each option */
/* debug */
debug = args_info.debug_flag;
/* listen */
/* Do hostname lookup to translate hostname to IP address */
/* Any port listening is not possible as a valid address is */
/* required for create_pdp_context_response messages */
if (args_info.listen_arg) {
if (!(host = gethostbyname(args_info.listen_arg))) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Invalid listening address: %s!", args_info.listen_arg);
exit(1);
}
else {
memcpy(&listen_.s_addr, host->h_addr, host->h_length);
}
}
else {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Listening address must be specified! "
"Please use command line option --listen or "
"edit %s configuration file\n", args_info.conf_arg);
exit(1);
}
/* net */
/* Store net as in_addr net and mask */
if (args_info.net_arg) {
if(ippool_aton(&net, &mask, args_info.net_arg, 0)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Invalid network address: %s!", args_info.net_arg);
exit(1);
}
netaddr.s_addr = htonl(ntohl(net.s_addr) + 1);
destaddr.s_addr = htonl(ntohl(net.s_addr) + 1);
}
else {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Network address must be specified: %s!", args_info.net_arg);
exit(1);
}
/* dynip */
if (!args_info.dynip_arg) {
if (ippool_new(&ippool, args_info.net_arg, NULL, 1, 0,
IPPOOL_NONETWORK | IPPOOL_NOGATEWAY | IPPOOL_NOBROADCAST)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to allocate IP pool!");
exit(1);
}
}
else {
if (ippool_new(&ippool, args_info.dynip_arg, NULL, 1 ,0,
IPPOOL_NONETWORK | IPPOOL_NOGATEWAY | IPPOOL_NOBROADCAST)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to allocate IP pool!");
exit(1);
}
}
/* DNS1 and DNS2 */
#ifdef HAVE_INET_ATON
dns1.s_addr = 0;
if (args_info.pcodns1_arg) {
if (0 == inet_aton(args_info.pcodns1_arg, &dns1)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to convert pcodns1!");
exit(1);
}
}
dns2.s_addr = 0;
if (args_info.pcodns2_arg) {
if (0 == inet_aton(args_info.pcodns2_arg, &dns2)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to convert pcodns2!");
exit(1);
}
}
#else
dns1.s_addr = 0;
if (args_info.pcodns1_arg) {
dns1.s_addr = inet_addr(args_info.pcodns1_arg);
if (dns1.s_addr == -1) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to convert pcodns1!");
exit(1);
}
}
dns2.s_addr = 0;
if (args_info.pcodns2_arg) {
dns2.s_addr = inet_addr(args_info.pcodns2_arg);
if (dns2.s_addr == -1) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to convert pcodns2!");
exit(1);
}
}
#endif
pco.l = 20;
pco.v[0] = 0x80; /* x0000yyy x=1, yyy=000: PPP */
pco.v[1] = 0x80; /* IPCP */
pco.v[2] = 0x21;
pco.v[3] = 0x10; /* Length of contents */
pco.v[4] = 0x02; /* ACK */
pco.v[5] = 0x00; /* ID: Need to match request */
pco.v[6] = 0x00; /* Length */
pco.v[7] = 0x10;
pco.v[8] = 0x81; /* DNS 1 */
pco.v[9] = 0x06;
memcpy(&pco.v[10], &dns1, sizeof(dns1));
pco.v[14] = 0x83;
pco.v[15] = 0x06; /* DNS 2 */
memcpy(&pco.v[16], &dns2, sizeof(dns2));
/* ipup */
ipup = args_info.ipup_arg;
/* ipdown */
ipdown = args_info.ipdown_arg;
/* Timelimit */
timelimit = args_info.timelimit_arg;
starttime = time(NULL);
/* qos */
qos.l = 3;
qos.v[2] = (args_info.qos_arg) & 0xff;
qos.v[1] = ((args_info.qos_arg) >> 8) & 0xff;
qos.v[0] = ((args_info.qos_arg) >> 16) & 0xff;
/* apn */
if (strlen(args_info.apn_arg) > (sizeof(apn.v)-1)) {
printf("Invalid APN\n");
return -1;
}
apn.l = strlen(args_info.apn_arg) + 1;
apn.v[0] = (char) strlen(args_info.apn_arg);
strncpy(&apn.v[1], args_info.apn_arg, sizeof(apn.v)-1);
/* foreground */
/* If flag not given run as a daemon */
if (!args_info.fg_flag)
{
closelog();
/* Close the standard file descriptors. */
/* Is this really needed ? */
freopen("/dev/null", "w", stdout);
freopen("/dev/null", "w", stderr);
freopen("/dev/null", "r", stdin);
daemon(0, 0);
/* Open log again. This time with new pid */
openlog(PACKAGE, LOG_PID, LOG_DAEMON);
}
/* pidfile */
/* This has to be done after we have our final pid */
if (args_info.pidfile_arg) {
log_pid(args_info.pidfile_arg);
}
if (debug) printf("gtpclient: Initialising GTP tunnel\n");
if (gtp_new(&gsn, args_info.statedir_arg, &listen_, GTP_MODE_GGSN)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to create gtp");
exit(1);
}
if (gsn->fd0 > maxfd) maxfd = gsn->fd0;
if (gsn->fd1c > maxfd) maxfd = gsn->fd1c;
if (gsn->fd1u > maxfd) maxfd = gsn->fd1u;
gtp_set_cb_data_ind(gsn, encaps_tun);
gtp_set_cb_delete_context(gsn, delete_context);
gtp_set_cb_create_context_ind(gsn, create_context_ind);
/* Create a tunnel interface */
if (debug) printf("Creating tun interface\n");
if (tun_new((struct tun_t**) &tun)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to create tun");
if (debug) printf("Failed to create tun\n");
exit(1);
}
if (debug) printf("Setting tun IP address\n");
if (tun_setaddr(tun, &netaddr, &destaddr, &mask)) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"Failed to set tun IP address");
if (debug) printf("Failed to set tun IP address\n");
exit(1);
}
tun_set_cb_ind(tun, cb_tun_ind);
if (tun->fd > maxfd) maxfd = tun->fd;
if (ipup) tun_runscript(tun, ipup);
/******************************************************************/
/* Main select loop */
/******************************************************************/
while (((starttime + timelimit) > time(NULL)) || (0 == timelimit)) {
FD_ZERO(&fds);
if (tun) FD_SET(tun->fd, &fds);
FD_SET(gsn->fd0, &fds);
FD_SET(gsn->fd1c, &fds);
FD_SET(gsn->fd1u, &fds);
gtp_retranstimeout(gsn, &idleTime);
switch (select(maxfd + 1, &fds, NULL, NULL, &idleTime)) {
case -1: /* errno == EINTR : unblocked signal */
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"select() returned -1");
break;
case 0:
/* printf("Select returned 0\n"); */
gtp_retrans(gsn); /* Only retransmit if nothing else */
break;
default:
break;
}
if (tun->fd != -1 && FD_ISSET(tun->fd, &fds) &&
tun_decaps(tun) < 0) {
sys_err(LOG_ERR, __FILE__, __LINE__, 0,
"TUN read failed (fd)=(%d)", tun->fd);
}
if (FD_ISSET(gsn->fd0, &fds))
gtp_decaps0(gsn);
if (FD_ISSET(gsn->fd1c, &fds))
gtp_decaps1c(gsn);
if (FD_ISSET(gsn->fd1u, &fds))
gtp_decaps1u(gsn);
}
gtp_free(gsn);
tun_free(tun);
return 1;
}