| /* |
| * OpenGGSN - Gateway GPRS Support Node |
| * Copyright (C) 2002 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. |
| * |
| * The initial developer of the original code is |
| * Jens Jakobsen <jj@openggsn.org> |
| * |
| * Contributor(s): |
| * |
| */ |
| |
| /* ggsn.c |
| * |
| */ |
| |
| #ifdef __linux__ |
| #define _GNU_SOURCE 1 /* strdup() prototype, broken arpa/inet.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 <unistd.h> |
| |
| #include <sys/socket.h> |
| #include <sys/ioctl.h> |
| #include <net/if.h> |
| #include <features.h> |
| |
| #include <errno.h> |
| |
| #include <asm/types.h> |
| #include <sys/socket.h> |
| #include <linux/netlink.h> |
| |
| #include <time.h> |
| |
| #include "tun.h" |
| #include "../gtp/pdp.h" |
| #include "../gtp/gtp.h" |
| #include "cmdline.h" |
| |
| |
| int maxfd = 0; /* For select() */ |
| int tun_fd = -1; /* Network file descriptor */ |
| struct tun_t *tun; /* TUN instance */ |
| struct in_addr net, mask; /* Network interface */ |
| int debug; /* Print debug output */ |
| |
| |
| /* 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) |
| return; |
| fprintf(file, "%d\n", getpid()); |
| fclose(file); |
| } |
| |
| |
| 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 getip(struct pdp_t *pdp, void* ipif, struct ul66_t *eua, |
| struct in_addr *net, struct in_addr *mask) { |
| struct in_addr addr; |
| uint32_t ip_start, ip_end, ip_cur; |
| struct pdp_t *pdp_; |
| struct ul66_t eua_; |
| |
| if (debug) { |
| printf("Begin getip %d %d %2x%2x%2x%2x\n", (unsigned)ipif, eua->l, |
| eua->v[2],eua->v[3],eua->v[4],eua->v[5]); |
| } |
| |
| ip_start = ntoh32(net->s_addr & mask->s_addr); |
| ip_end = ntoh32(hton32(ip_start) | ~mask->s_addr); |
| |
| /* By convention the first address is the network address, and the last */ |
| /* address is the broadcast address. This way two IP addresses are "lost" */ |
| ip_start++; |
| |
| if (eua->l == 0) { /* No address supplied. Find one that is available! */ |
| /* This routine does linear search. In order to support millions of |
| * addresses we should instead keep a linked list of available adresses */ |
| for (ip_cur = ip_start; ip_cur < ip_end; ip_cur++) { |
| addr.s_addr = hton32(ip_cur); |
| pdp_ntoeua(&addr, &eua_); |
| if (pdp_ipget(&pdp_, ipif, &eua_) == -1) { |
| pdp_ntoeua(&addr, &pdp->eua); |
| pdp->ipif = ipif; |
| return 0; |
| }; |
| } |
| return EOF; /* No addresses available */ |
| } |
| else { /* Address supplied */ |
| if (pdp_ipget(&pdp_, ipif, eua) == -1) { |
| pdp->ipif = ipif; |
| pdp->eua.l = eua->l; |
| memcpy(pdp->eua.v, eua->v, eua->l); |
| return 0; |
| } |
| else return EOF; /* Specified address not available */ |
| } |
| } |
| |
| |
| int delete_context(struct pdp_t *pdp) { |
| if (debug) printf("Deleting PDP context\n"); |
| pdp_ipdel(pdp); |
| return 0; |
| } |
| |
| |
| |
| int create_context(struct pdp_t *pdp) { |
| |
| 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_neg)); |
| |
| getip(pdp, tun, &pdp->eua, &net, &mask); |
| pdp_ipset(pdp, pdp->ipif, &pdp->eua); |
| |
| return 0; /* Success */ |
| } |
| |
| |
| |
| int create_tun() { |
| char buf[1024]; |
| char snet[100], smask[100]; |
| |
| if ((tun_fd = tun_newtun((struct tun_t**) &tun)) > maxfd) |
| maxfd = tun_fd; |
| |
| if (tun_fd == -1) { |
| printf("Failed to open tun\n"); |
| exit(1); |
| } |
| |
| strncpy(snet, inet_ntoa(net), 100); |
| strncpy(smask, inet_ntoa(mask), 100); |
| |
| sprintf(buf, "/sbin/ifconfig %s %s mtu 1450 netmask %s", |
| tun->devname, snet, smask); |
| if (debug) printf("%s\n", buf); |
| system(buf); |
| |
| system("echo 1 > /proc/sys/net/ipv4/ip_forward"); |
| |
| return 0; |
| } |
| |
| |
| int encaps_gtp(void *gsn, struct tun_t *tun, void *pack, unsigned len) { |
| struct pdp_t *pdp; |
| struct in_addr addr; |
| struct ul66_t eua; |
| /*printf("encaps_gtp. Packet received: forwarding to gtp.\n");*/ |
| /* First we need to extract the IP destination address */ |
| memcpy(&addr.s_addr, pack+16, 4); /* This ought to be dest addr */ |
| pdp_ntoeua(&addr, &eua); |
| if (pdp_ipget(&pdp, tun, &eua) == 0) { |
| return gtp_gpdu((struct gsn_t*) gsn, pdp, pack, len); |
| } |
| else { |
| if (debug) printf("Received packet with no destination!!!\n"); |
| return 0; |
| } |
| } |
| |
| |
| int encaps_tun(struct pdp_t *pdp, void *pack, unsigned len) { |
| /* 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; |
| |
| struct in_addr listen; |
| |
| int gtpfd = -1; /* Network file descriptor */ |
| struct gsn_t *gsn; /* GSN instance */ |
| |
| fd_set fds; /* For select() */ |
| struct timeval idleTime; /* How long to select() */ |
| |
| struct ul_t qos, apn; |
| unsigned char qosh[3], apnh[256]; |
| |
| 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);*/ |
| openlog(PACKAGE, (LOG_PID | LOG_PERROR), LOG_DAEMON); |
| |
| if (cmdline_parser (argc, argv, &args_info) != 0) |
| exit(1); |
| if (args_info.debug_flag) { |
| 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); |
| printf("apn: %s\n", args_info.apn_arg); |
| printf("net: %s\n", args_info.net_arg); |
| printf("mask: %s\n", args_info.mask_arg); |
| printf("pidfile: %s\n", args_info.pidfile_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); |
| printf("apn: %s\n", args_info.apn_arg); |
| printf("net: %s\n", args_info.net_arg); |
| printf("mask: %s\n", args_info.mask_arg); |
| printf("pidfile: %s\n", args_info.pidfile_arg); |
| printf("statedir: %s\n", args_info.statedir_arg); |
| printf("timelimit: %d\n", args_info.timelimit_arg); |
| } |
| |
| /* Handle each option */ |
| |
| /* 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); |
| } |
| |
| /* debug */ |
| debug = args_info.debug_flag; |
| |
| /* pidfile */ |
| /* This has to be done after we have our final pid */ |
| if (args_info.pidfile_arg) { |
| log_pid(args_info.pidfile_arg); |
| } |
| |
| /* listen */ |
| /* If no listen option is specified listen to any local port */ |
| /* Do hostname lookup to translate hostname to IP address */ |
| if (args_info.listen_arg) { |
| if (!(host = gethostbyname(args_info.listen_arg))) { |
| fprintf(stderr, "%s: Invalid listening address: %s!\n", |
| PACKAGE, args_info.listen_arg); |
| syslog(LOG_ERR, "Invalid listening address: %s!", |
| args_info.listen_arg); |
| return 1; |
| } |
| else { |
| memcpy(&listen.s_addr, host->h_addr, host->h_length); |
| } |
| } |
| else { |
| listen.s_addr = htonl(INADDR_ANY); |
| } |
| |
| /* net */ |
| /* Store net as in_addr */ |
| if (args_info.net_arg) { |
| if (!inet_aton(args_info.net_arg, &net)) { |
| fprintf(stderr, "%s: Invalid network address: %s!\n", |
| PACKAGE, args_info.net_arg); |
| syslog(LOG_ERR, "Invalid network address: %s!", |
| args_info.net_arg); |
| return 1; |
| } |
| } |
| |
| /* mask */ |
| /* Store mask as in_addr */ |
| if (args_info.mask_arg) { |
| if (!inet_aton(args_info.mask_arg, &mask)) { |
| fprintf(stderr, "%s: Invalid network mask: %s!\n", |
| PACKAGE, args_info.mask_arg); |
| syslog(LOG_ERR, "Invalid network mask: %s!", |
| args_info.mask_arg); |
| return 1; |
| } |
| } |
| |
| /* Timelimit */ |
| timelimit = args_info.timelimit_arg; |
| starttime = time(NULL); |
| |
| /* qos */ |
| qos.l = 3; |
| qos.v = qosh; |
| 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)>255) { |
| printf("invalid APN\n"); |
| exit(1); |
| } |
| apn.l = strlen(args_info.apn_arg) + 1; |
| apn.v = apnh; |
| apn.v[0] = (char) strlen(args_info.apn_arg); |
| strncpy(&apn.v[1], args_info.apn_arg, 255); |
| |
| if (debug) printf("gtpclient: Initialising GTP tunnel\n"); |
| |
| if ((gtpfd = gtp_new(&gsn, args_info.statedir_arg, &listen)) > maxfd) |
| maxfd = gtpfd; |
| |
| if ((gtpfd = gtp_fd(gsn)) > maxfd) |
| maxfd = gtpfd; |
| |
| |
| gtp_set_cb_gpdu(gsn, encaps_tun); |
| gtp_set_cb_delete_context(gsn, delete_context); |
| |
| gtp_set_cb_create_context(gsn, create_context); |
| create_tun(); |
| |
| /******************************************************************/ |
| /* Main select loop */ |
| /******************************************************************/ |
| |
| while (((starttime + timelimit) > time(NULL)) || (0 == timelimit)) { |
| |
| FD_ZERO(&fds); |
| if (tun_fd != -1) FD_SET(tun_fd, &fds); |
| if (gtpfd != -1) FD_SET(gtpfd, &fds); |
| |
| gtp_retranstimeout(gsn, &idleTime); |
| switch (select(maxfd + 1, &fds, NULL, NULL, &idleTime)) { |
| case -1: /* Error with select() * |
| if (errno != EINTR) |
| syslog(LOG_ERR, "CTRL: Error with select(), quitting"); |
| *goto leave_clear_call;*/ |
| syslog(LOG_ERR, "GGSN: select = -1"); |
| break; |
| case 0: |
| gtp_retrans(gsn); /* Only retransmit if nothing else */ |
| break; |
| default: |
| break; |
| } |
| |
| if (tun_fd != -1 && FD_ISSET(tun_fd, &fds) && |
| tun_decaps(tun, encaps_gtp, gsn) < 0) { |
| syslog(LOG_ERR, "TUN read failed (fd)=(%d)", tun_fd); |
| } |
| |
| if (gtpfd != -1 && FD_ISSET(gtpfd, &fds) && |
| gtp_decaps(gsn) < 0) { |
| syslog(LOG_ERR, "GTP read failed (gre)=(%d)", gtpfd); |
| } |
| |
| |
| } |
| |
| gtp_free(gsn); |
| |
| return 1; |
| |
| } |
| |