| /* |
| * OsmoGGSN - Gateway GPRS Support Node |
| * Copyright (C) 2002, 2003, 2004 Mondru AB. |
| * Copyright (C) 2017-2019 by Harald Welte <laforge@gnumonks.org> |
| * |
| * 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 <getopt.h> |
| #include <ctype.h> |
| #include <signal.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <inttypes.h> |
| #include <errno.h> |
| #include <sys/types.h> |
| #include <sys/ioctl.h> |
| |
| #include <net/if.h> |
| #include <arpa/inet.h> |
| #include <netinet/in.h> |
| #include <netinet/ip.h> |
| #include <netinet/ip6.h> |
| |
| #include <osmocom/core/timer.h> |
| #include <osmocom/ctrl/control_if.h> |
| #include <osmocom/gsm/apn.h> |
| |
| #include "../lib/tun.h" |
| #include "../lib/ippool.h" |
| #include "../lib/syserr.h" |
| #include "../lib/in46_addr.h" |
| #include "../lib/gtp-kernel.h" |
| #include "../lib/util.h" |
| #include "../gtp/pdp.h" |
| #include "../gtp/gtp.h" |
| #include "../lib/icmpv6.h" |
| #include "pco.h" |
| #include "ggsn.h" |
| |
| static int ggsn_tun_fd_cb(struct osmo_fd *fd, unsigned int what); |
| static int cb_tun_ind(struct tun_t *tun, void *pack, unsigned len); |
| |
| void ggsn_close_one_pdp(struct pdp_t *pdp) |
| { |
| LOGPPDP(LOGL_DEBUG, pdp, "Sending DELETE PDP CTX due to shutdown\n"); |
| gtp_delete_context_req2(pdp->gsn, pdp, NULL, 1); |
| /* We have nothing more to do with pdp ctx, free it. Upon cb_delete_context |
| called during this call we'll clean up ggsn related stuff attached to this |
| pdp context. After this call, ippool member is cleared so |
| data is no longer valid and should not be accessed anymore. */ |
| gtp_freepdp_teardown(pdp->gsn, pdp); |
| } |
| |
| static void pool_close_all_pdp(struct ippool_t *pool) |
| { |
| unsigned int i; |
| |
| if (!pool) |
| return; |
| |
| for (i = 0; i < pool->listsize; i++) { |
| struct ippoolm_t *member = &pool->member[i]; |
| struct pdp_t *pdp; |
| |
| if (!member->inuse) |
| continue; |
| pdp = member->peer; |
| if (!pdp) |
| continue; |
| ggsn_close_one_pdp(pdp); |
| } |
| } |
| |
| int apn_stop(struct apn_ctx *apn) |
| { |
| LOGPAPN(LOGL_NOTICE, apn, "Stopping\n"); |
| /* check if pools have any active PDP contexts and bail out */ |
| pool_close_all_pdp(apn->v4.pool); |
| pool_close_all_pdp(apn->v6.pool); |
| |
| /* shutdown whatever old state might be left */ |
| if (apn->tun.tun) { |
| /* run ip-down script */ |
| if (apn->tun.cfg.ipdown_script) { |
| LOGPAPN( LOGL_INFO, apn, "Running %s\n", apn->tun.cfg.ipdown_script); |
| tun_runscript(apn->tun.tun, apn->tun.cfg.ipdown_script); |
| } |
| if (apn->cfg.gtpu_mode == APN_GTPU_MODE_TUN) { |
| /* release tun device */ |
| LOGPAPN(LOGL_INFO, apn, "Closing TUN device %s\n", apn->tun.tun->devname); |
| osmo_fd_unregister(&apn->tun.fd); |
| } |
| tun_free(apn->tun.tun); |
| apn->tun.tun = NULL; |
| } |
| |
| if (apn->v4.pool) { |
| LOGPAPN(LOGL_INFO, apn, "Releasing IPv4 pool\n"); |
| ippool_free(apn->v4.pool); |
| apn->v4.pool = NULL; |
| } |
| if (apn->v6.pool) { |
| LOGPAPN(LOGL_INFO, apn, "Releasing IPv6 pool\n"); |
| ippool_free(apn->v6.pool); |
| apn->v6.pool = NULL; |
| } |
| |
| apn->started = false; |
| return 0; |
| } |
| |
| |
| static int alloc_ippool_blacklist(struct apn_ctx *apn, struct in46_prefix **blacklist, bool ipv6) |
| { |
| |
| int flags, len, len2, i; |
| |
| *blacklist = NULL; |
| |
| if (ipv6) |
| flags = IP_TYPE_IPv6_NONLINK; |
| else |
| flags = IP_TYPE_IPv4; |
| |
| while (1) { |
| len = netdev_ip_local_get(apn->tun.cfg.dev_name, NULL, 0, flags); |
| if (len < 1) |
| return len; |
| |
| *blacklist = talloc_zero_size(apn, len * sizeof(struct in46_prefix)); |
| len2 = netdev_ip_local_get(apn->tun.cfg.dev_name, *blacklist, len, flags); |
| if (len2 < 1) { |
| talloc_free(*blacklist); |
| *blacklist = NULL; |
| return len2; |
| } |
| |
| if (len2 > len) { /* iface was added between 2 calls, repeat operation */ |
| talloc_free(*blacklist); |
| *blacklist = NULL; |
| } else |
| break; |
| } |
| |
| for (i = 0; i < len2; i++) |
| LOGPAPN(LOGL_INFO, apn, "Blacklist tun IP %s\n", |
| in46p_ntoa(&(*blacklist)[i])); |
| |
| return len2; |
| } |
| |
| /* actually start the APN with its current config */ |
| int apn_start(struct apn_ctx *apn) |
| { |
| int ippool_flags = IPPOOL_NONETWORK | IPPOOL_NOBROADCAST; |
| struct in46_prefix ipv6_tun_linklocal_ip; |
| struct in46_prefix *blacklist; |
| int blacklist_size; |
| struct gsn_t *gsn = apn->ggsn->gsn; |
| int rc; |
| |
| if (apn->started) |
| return 0; |
| |
| LOGPAPN(LOGL_INFO, apn, "Starting\n"); |
| switch (apn->cfg.gtpu_mode) { |
| case APN_GTPU_MODE_TUN: |
| LOGPAPN(LOGL_INFO, apn, "Opening TUN device %s\n", apn->tun.cfg.dev_name); |
| if (tun_new(&apn->tun.tun, apn->tun.cfg.dev_name, false, -1, -1)) { |
| LOGPAPN(LOGL_ERROR, apn, "Failed to configure tun device\n"); |
| return -1; |
| } |
| LOGPAPN(LOGL_INFO, apn, "Opened TUN device %s\n", apn->tun.tun->devname); |
| |
| /* Register with libosmcoore */ |
| osmo_fd_setup(&apn->tun.fd, apn->tun.tun->fd, OSMO_FD_READ, ggsn_tun_fd_cb, apn, 0); |
| osmo_fd_register(&apn->tun.fd); |
| |
| /* Set TUN library callback */ |
| tun_set_cb_ind(apn->tun.tun, cb_tun_ind); |
| break; |
| case APN_GTPU_MODE_KERNEL_GTP: |
| LOGPAPN(LOGL_INFO, apn, "Opening Kernel GTP device %s\n", apn->tun.cfg.dev_name); |
| if (apn->cfg.apn_type_mask & (APN_TYPE_IPv6|APN_TYPE_IPv4v6)) { |
| LOGPAPN(LOGL_ERROR, apn, "Kernel GTP currently supports only IPv4\n"); |
| apn_stop(apn); |
| return -1; |
| } |
| if (gsn == NULL) { |
| /* skip bringing up the APN now if the GSN is not initialized yet. |
| * This happens during initial load of the config file, as the |
| * "no shutdown" in the ggsn node only happens after the "apn" nodes |
| * are brought up */ |
| LOGPAPN(LOGL_NOTICE, apn, "Skipping APN start\n"); |
| return 0; |
| } |
| /* use GTP kernel module for data packet encapsulation */ |
| if (tun_new(&apn->tun.tun, apn->tun.cfg.dev_name, true, gsn->fd0, gsn->fd1u)) { |
| LOGPAPN(LOGL_ERROR, apn, "Failed to configure Kernel GTP device\n"); |
| return -1; |
| } |
| break; |
| default: |
| LOGPAPN(LOGL_ERROR, apn, "Unknown GTPU Mode %d\n", apn->cfg.gtpu_mode); |
| return -1; |
| } |
| |
| /* common initialization below */ |
| |
| /* set back-pointer from TUN device to APN */ |
| apn->tun.tun->priv = apn; |
| |
| if (apn->v4.cfg.ifconfig_prefix.addr.len) { |
| LOGPAPN(LOGL_INFO, apn, "Setting tun IP address %s\n", |
| in46p_ntoa(&apn->v4.cfg.ifconfig_prefix)); |
| if (tun_addaddr(apn->tun.tun, &apn->v4.cfg.ifconfig_prefix.addr, NULL, |
| apn->v4.cfg.ifconfig_prefix.prefixlen)) { |
| LOGPAPN(LOGL_ERROR, apn, "Failed to set tun IPv4 address %s: %s\n", |
| in46p_ntoa(&apn->v4.cfg.ifconfig_prefix), strerror(errno)); |
| apn_stop(apn); |
| return -1; |
| } |
| } |
| |
| if (apn->v6.cfg.ifconfig_prefix.addr.len) { |
| LOGPAPN(LOGL_INFO, apn, "Setting tun IPv6 address %s\n", |
| in46p_ntoa(&apn->v6.cfg.ifconfig_prefix)); |
| if (tun_addaddr(apn->tun.tun, &apn->v6.cfg.ifconfig_prefix.addr, NULL, |
| apn->v6.cfg.ifconfig_prefix.prefixlen)) { |
| LOGPAPN(LOGL_ERROR, apn, "Failed to set tun IPv6 address %s: %s. " |
| "Ensure you have ipv6 support and not used the disable_ipv6 sysctl?\n", |
| in46p_ntoa(&apn->v6.cfg.ifconfig_prefix), strerror(errno)); |
| apn_stop(apn); |
| return -1; |
| } |
| } |
| |
| if (apn->v6.cfg.ll_prefix.addr.len) { |
| LOGPAPN(LOGL_INFO, apn, "Setting tun IPv6 link-local address %s\n", |
| in46p_ntoa(&apn->v6.cfg.ll_prefix)); |
| if (tun_addaddr(apn->tun.tun, &apn->v6.cfg.ll_prefix.addr, NULL, |
| apn->v6.cfg.ll_prefix.prefixlen)) { |
| LOGPAPN(LOGL_ERROR, apn, "Failed to set tun IPv6 link-local address %s: %s. " |
| "Ensure you have ipv6 support and not used the disable_ipv6 sysctl?\n", |
| in46p_ntoa(&apn->v6.cfg.ll_prefix), strerror(errno)); |
| apn_stop(apn); |
| return -1; |
| } |
| apn->v6_lladdr = apn->v6.cfg.ll_prefix.addr.v6; |
| } |
| |
| if (apn->tun.cfg.ipup_script) { |
| LOGPAPN(LOGL_INFO, apn, "Running ip-up script %s\n", |
| apn->tun.cfg.ipup_script); |
| tun_runscript(apn->tun.tun, apn->tun.cfg.ipup_script); |
| } |
| |
| if (apn->cfg.apn_type_mask & (APN_TYPE_IPv6|APN_TYPE_IPv4v6) && |
| apn->v6.cfg.ll_prefix.addr.len == 0) { |
| rc = tun_ip_local_get(apn->tun.tun, &ipv6_tun_linklocal_ip, 1, IP_TYPE_IPv6_LINK); |
| if (rc < 1) { |
| LOGPAPN(LOGL_ERROR, apn, "Cannot obtain IPv6 link-local address of interface: %s\n", |
| rc ? strerror(errno) : "tun interface has no link-local IP assigned"); |
| apn_stop(apn); |
| return -1; |
| } |
| apn->v6_lladdr = ipv6_tun_linklocal_ip.addr.v6; |
| } |
| |
| /* Create IPv4 pool */ |
| if (apn->v4.cfg.dynamic_prefix.addr.len) { |
| LOGPAPN(LOGL_INFO, apn, "Creating IPv4 pool %s\n", |
| in46p_ntoa(&apn->v4.cfg.dynamic_prefix)); |
| if ((blacklist_size = alloc_ippool_blacklist(apn, &blacklist, false)) < 0) |
| LOGPAPN(LOGL_ERROR, apn, "Failed obtaining IPv4 tun IPs\n"); |
| if (ippool_new(&apn->v4.pool, &apn->v4.cfg.dynamic_prefix, |
| &apn->v4.cfg.static_prefix, ippool_flags, |
| blacklist, blacklist_size)) { |
| LOGPAPN(LOGL_ERROR, apn, "Failed to create IPv4 pool\n"); |
| talloc_free(blacklist); |
| apn_stop(apn); |
| return -1; |
| } |
| talloc_free(blacklist); |
| } |
| |
| /* Create IPv6 pool */ |
| if (apn->v6.cfg.dynamic_prefix.addr.len) { |
| LOGPAPN(LOGL_INFO, apn, "Creating IPv6 pool %s\n", |
| in46p_ntoa(&apn->v6.cfg.dynamic_prefix)); |
| if ((blacklist_size = alloc_ippool_blacklist(apn, &blacklist, true)) < 0) |
| LOGPAPN(LOGL_ERROR, apn, "Failed obtaining IPv6 tun IPs\n"); |
| if (ippool_new(&apn->v6.pool, &apn->v6.cfg.dynamic_prefix, |
| &apn->v6.cfg.static_prefix, ippool_flags, |
| blacklist, blacklist_size)) { |
| LOGPAPN(LOGL_ERROR, apn, "Failed to create IPv6 pool\n"); |
| talloc_free(blacklist); |
| apn_stop(apn); |
| return -1; |
| } |
| talloc_free(blacklist); |
| } |
| |
| LOGPAPN(LOGL_NOTICE, apn, "Successfully started\n"); |
| apn->started = true; |
| return 0; |
| } |
| |
| static bool send_trap(const struct gsn_t *gsn, const struct pdp_t *pdp, const struct ippoolm_t *member, const char *var) |
| { |
| char addrbuf[256]; |
| char val[NAMESIZE]; |
| |
| const char *addrstr = in46a_ntop(&member->addr, addrbuf, sizeof(addrbuf)); |
| |
| snprintf(val, sizeof(val), "%s,%s", imsi_gtp2str(&pdp->imsi), addrstr); |
| |
| if (ctrl_cmd_send_trap(g_ctrlh, var, val) < 0) { |
| LOGPPDP(LOGL_ERROR, pdp, "Failed to create and send TRAP %s\n", var); |
| return false; |
| } |
| return true; |
| } |
| |
| static int delete_context(struct pdp_t *pdp) |
| { |
| struct gsn_t *gsn = pdp->gsn; |
| struct pdp_priv_t *pdp_priv = pdp->priv; |
| struct apn_ctx *apn; |
| struct ippoolm_t *member; |
| int i; |
| |
| LOGPPDP(LOGL_INFO, pdp, "Deleting PDP context\n"); |
| |
| for (i = 0; i < 2; i++) { |
| if (pdp->peer[i]) { |
| member = pdp->peer[i]; |
| send_trap(gsn, pdp, member, "imsi-rem-ip"); /* TRAP with IP removal */ |
| ippool_freeip(member->pool, member); |
| } else if (i == 0) { |
| LOGPPDP(LOGL_ERROR, pdp, "Cannot find/free IP Pool member\n"); |
| } |
| } |
| |
| if (!pdp_priv) { |
| LOGPPDP(LOGL_NOTICE, pdp, "Deleting PDP context: without private structure!\n"); |
| return 0; |
| } |
| |
| /* Remove from SGSN */ |
| sgsn_peer_remove_pdp_priv(pdp_priv); |
| |
| apn = pdp_priv->apn; |
| if (apn && apn->cfg.gtpu_mode == APN_GTPU_MODE_KERNEL_GTP) { |
| if (gtp_kernel_tunnel_del(pdp, apn->tun.cfg.dev_name)) { |
| LOGPPDP(LOGL_ERROR, pdp, "Cannot delete tunnel from kernel:%s\n", |
| strerror(errno)); |
| } |
| } |
| |
| talloc_free(pdp_priv); |
| |
| return 0; |
| } |
| |
| static bool apn_supports_ipv4(const struct apn_ctx *apn) |
| { |
| if (apn->v4.cfg.static_prefix.addr.len || apn->v4.cfg.dynamic_prefix.addr.len) |
| return true; |
| return false; |
| } |
| |
| static bool apn_supports_ipv6(const struct apn_ctx *apn) |
| { |
| if (apn->v6.cfg.static_prefix.addr.len || apn->v6.cfg.dynamic_prefix.addr.len) |
| return true; |
| return false; |
| } |
| |
| static struct sgsn_peer* ggsn_find_sgsn(struct ggsn_ctx *ggsn, struct in_addr *peer_addr) |
| { |
| struct sgsn_peer *sgsn; |
| |
| llist_for_each_entry(sgsn, &ggsn->sgsn_list, entry) { |
| if (memcmp(&sgsn->addr, peer_addr, sizeof(*peer_addr)) == 0) |
| return sgsn; |
| } |
| return NULL; |
| } |
| |
| static struct sgsn_peer* ggsn_find_or_create_sgsn(struct ggsn_ctx *ggsn, struct pdp_t *pdp) |
| { |
| struct sgsn_peer *sgsn; |
| struct in_addr ia; |
| |
| if (gsna2in_addr(&ia, &pdp->gsnrc)) { |
| LOGPPDP(LOGL_ERROR, pdp, "Failed parsing gsnrc (len=%u) to discover SGSN\n", |
| pdp->gsnrc.l); |
| return NULL; |
| } |
| |
| if ((sgsn = ggsn_find_sgsn(ggsn, &ia))) |
| return sgsn; |
| |
| sgsn = sgsn_peer_allocate(ggsn, &ia, pdp->version); |
| llist_add(&sgsn->entry, &ggsn->sgsn_list); |
| return sgsn; |
| } |
| |
| int create_context_ind(struct pdp_t *pdp) |
| { |
| static char name_buf[256]; |
| struct gsn_t *gsn = pdp->gsn; |
| struct ggsn_ctx *ggsn = gsn->priv; |
| struct in46_addr addr[2]; |
| struct ippoolm_t *member = NULL, *addrv4 = NULL, *addrv6 = NULL; |
| char straddrv4[INET_ADDRSTRLEN], straddrv6[INET6_ADDRSTRLEN]; |
| struct apn_ctx *apn = NULL; |
| int rc, num_addr, i; |
| char *apn_name; |
| struct sgsn_peer *sgsn; |
| struct pdp_priv_t *pdp_priv; |
| |
| apn_name = osmo_apn_to_str(name_buf, pdp->apn_req.v, pdp->apn_req.l); |
| LOGPPDP(LOGL_DEBUG, pdp, "Processing create PDP context request for APN '%s'\n", |
| apn_name ? name_buf : "(NONE)"); |
| |
| /* First find an exact APN name match */ |
| if (apn_name != NULL) |
| apn = ggsn_find_apn(ggsn, name_buf); |
| /* ignore if the APN has not been started */ |
| if (apn && !apn->started) |
| apn = NULL; |
| |
| /* then try default (if any) */ |
| if (!apn) |
| apn = ggsn->cfg.default_apn; |
| /* ignore if the APN has not been started */ |
| if (apn && !apn->started) |
| apn = NULL; |
| |
| if (!apn) { |
| /* no APN found for what user requested */ |
| LOGPPDP(LOGL_NOTICE, pdp, "Unknown APN '%s', rejecting\n", name_buf); |
| gtp_create_context_resp(gsn, pdp, GTPCAUSE_MISSING_APN); |
| return 0; |
| } |
| |
| /* FIXME: implement context request for static IP addresses! */ |
| if (pdp->eua.l > 2) { |
| LOGPPDP(LOGL_ERROR, pdp, "Static IP addresses not supported: %s\n", |
| osmo_hexdump(pdp->eua.v, pdp->eua.l)); |
| gtp_create_context_resp(gsn, pdp, GTPCAUSE_NOT_SUPPORTED); |
| return 0; |
| } |
| |
| memcpy(pdp->qos_neg0, pdp->qos_req0, sizeof(pdp->qos_req0)); |
| |
| memcpy(pdp->qos_neg.v, pdp->qos_req.v, pdp->qos_req.l); /* TODO */ |
| pdp->qos_neg.l = pdp->qos_req.l; |
| |
| memset(addr, 0, sizeof(addr)); |
| if ((num_addr = in46a_from_eua(&pdp->eua, addr)) < 0) { |
| LOGPPDP(LOGL_ERROR, pdp, "Cannot decode EUA from MS/SGSN: %s\n", |
| osmo_hexdump(pdp->eua.v, pdp->eua.l)); |
| gtp_create_context_resp(gsn, pdp, GTPCAUSE_UNKNOWN_PDP); |
| return 0; |
| } |
| |
| /* Store the actual APN for logging and the VTY */ |
| rc = osmo_apn_from_str(pdp->apn_use.v, sizeof(pdp->apn_use.v), apn->cfg.name); |
| if (rc < 0) /* Unlikely this would happen, but anyway... */ |
| LOGPPDP(LOGL_ERROR, pdp, "Failed to store APN '%s'\n", apn->cfg.name); |
| pdp->apn_use.l = rc; |
| |
| /* Allocate dynamic addresses from the pool */ |
| for (i = 0; i < num_addr; i++) { |
| if (in46a_is_v4(&addr[i])) { |
| /* does this APN actually have an IPv4 pool? */ |
| if (!apn_supports_ipv4(apn)) |
| goto err_wrong_af; |
| |
| rc = ippool_newip(apn->v4.pool, &member, &addr[i], 0); |
| if (rc < 0) |
| goto err_pool_full; |
| /* copy back */ |
| memcpy(&addr[i].v4.s_addr, &member->addr.v4, 4); |
| |
| addrv4 = member; |
| |
| } else if (in46a_is_v6(&addr[i])) { |
| |
| /* does this APN actually have an IPv6 pool? */ |
| if (!apn_supports_ipv6(apn)) |
| goto err_wrong_af; |
| |
| rc = ippool_newip(apn->v6.pool, &member, &addr[i], 0); |
| if (rc < 0) |
| goto err_pool_full; |
| |
| /* IPv6 doesn't really send the real/allocated address at this point, but just |
| * the link-identifier which the MS shall use for router solicitation */ |
| /* initialize upper 64 bits to prefix, they are discarded by MS anyway */ |
| memcpy(addr[i].v6.s6_addr, &member->addr.v6, 8); |
| /* use allocated 64bit prefix as lower 64bit, used as link id by MS */ |
| memcpy(addr[i].v6.s6_addr+8, &member->addr.v6, 8); |
| |
| addrv6 = member; |
| } else |
| OSMO_ASSERT(0); |
| |
| pdp->peer[i] = member; |
| member->peer = pdp; |
| } |
| |
| in46a_to_eua(addr, num_addr, &pdp->eua); |
| |
| if (apn->cfg.gtpu_mode == APN_GTPU_MODE_KERNEL_GTP && apn_supports_ipv4(apn)) { |
| /* TODO: In IPv6, EUA doesn't contain the actual IP addr/prefix! */ |
| if (gtp_kernel_tunnel_add(pdp, apn->tun.cfg.dev_name) < 0) { |
| LOGPPDP(LOGL_ERROR, pdp, "Cannot add tunnel to kernel: %s\n", strerror(errno)); |
| gtp_create_context_resp(gsn, pdp, GTPCAUSE_SYS_FAIL); |
| return 0; |
| } |
| } |
| |
| pdp->ipif = apn->tun.tun; /* TODO */ |
| |
| pdp_priv = talloc_zero(ggsn, struct pdp_priv_t); |
| pdp->priv = pdp_priv; |
| pdp_priv->lib = pdp; |
| /* Create sgsn and assign pdp to it */ |
| sgsn = ggsn_find_or_create_sgsn(ggsn, pdp); |
| sgsn_peer_add_pdp_priv(sgsn, pdp_priv); |
| pdp_priv->apn = apn; |
| |
| /* TODO: change trap to send 2 IPs */ |
| if (!send_trap(gsn, pdp, member, "imsi-ass-ip")) { /* TRAP with IP assignment */ |
| gtp_create_context_resp(gsn, pdp, GTPCAUSE_NO_RESOURCES); |
| return 0; |
| } |
| |
| process_pco(apn, pdp); |
| |
| /* Transmit G-PDU sequence numbers (only) if configured in APN */ |
| pdp->tx_gpdu_seq = apn->cfg.tx_gpdu_seq; |
| |
| LOGPPDP(LOGL_INFO, pdp, "Successful PDP Context Creation: APN=%s(%s), TEIC=%u, IPv4=%s, IPv6=%s\n", |
| name_buf, apn->cfg.name, pdp->teic_own, |
| addrv4 ? inet_ntop(AF_INET, &addrv4->addr.v4, straddrv4, sizeof(straddrv4)) : "none", |
| addrv6 ? inet_ntop(AF_INET6, &addrv6->addr.v6, straddrv6, sizeof(straddrv6)) : "none"); |
| gtp_create_context_resp(gsn, pdp, GTPCAUSE_ACC_REQ); |
| return 0; /* Success */ |
| |
| err_pool_full: |
| LOGPPDP(LOGL_ERROR, pdp, "Cannot allocate IP address from pool (full!)\n"); |
| gtp_create_context_resp(gsn, pdp, -rc); |
| return 0; /* Already in use, or no more available */ |
| |
| err_wrong_af: |
| LOGPPDP(LOGL_ERROR, pdp, "APN doesn't support requested EUA / AF type\n"); |
| gtp_create_context_resp(gsn, pdp, GTPCAUSE_UNKNOWN_PDP); |
| return 0; |
| } |
| |
| /* Internet-originated IP packet, needs to be sent via GTP towards MS */ |
| static int cb_tun_ind(struct tun_t *tun, void *pack, unsigned len) |
| { |
| struct apn_ctx *apn = tun->priv; |
| struct ippoolm_t *ipm; |
| struct in46_addr dst; |
| struct iphdr *iph = (struct iphdr *)pack; |
| struct ip6_hdr *ip6h = (struct ip6_hdr *)pack; |
| struct ippool_t *pool; |
| char straddr[INET6_ADDRSTRLEN]; |
| uint8_t pref_offset; |
| |
| switch (iph->version) { |
| case 4: |
| if (len < sizeof(*iph) || len < 4*iph->ihl) |
| return -1; |
| dst.len = 4; |
| dst.v4.s_addr = iph->daddr; |
| pool = apn->v4.pool; |
| break; |
| case 6: |
| /* Due to the fact that 3GPP requires an allocation of a |
| * /64 prefix to each MS, we must instruct |
| * ippool_getip() below to match only the leading /64 |
| * prefix, i.e. the first 8 bytes of the address. If the ll addr |
| * is used, then the match should be done on the trailing 64 |
| * bits. */ |
| dst.len = 8; |
| pref_offset = IN6_IS_ADDR_LINKLOCAL(&ip6h->ip6_dst) ? 8 : 0; |
| memcpy(&dst.v6, ((uint8_t*)&ip6h->ip6_dst) + pref_offset, 8); |
| pool = apn->v6.pool; |
| break; |
| default: |
| LOGTUN(LOGL_NOTICE, tun, "non-IPv%u packet received\n", iph->version); |
| return -1; |
| } |
| |
| /* IPv6 packet but no IPv6 pool, or IPv4 packet with no IPv4 pool */ |
| if (!pool) |
| return 0; |
| |
| if (ippool_getip(pool, &ipm, &dst)) { |
| LOGTUN(LOGL_DEBUG, tun, "Received packet for APN(%s) with no PDP contex! (%s)\n", |
| apn->cfg.name, |
| iph->version == 4 ? |
| inet_ntop(AF_INET, &iph->saddr, straddr, sizeof(straddr)) : |
| inet_ntop(AF_INET6, &ip6h->ip6_src, straddr, sizeof(straddr))); |
| return 0; |
| } |
| LOGTUN(LOGL_DEBUG, tun, "Received packet for APN(%s)\n", apn->cfg.name); |
| |
| if (ipm->peer) /* Check if a peer protocol is defined */ |
| gtp_data_req(apn->ggsn->gsn, (struct pdp_t *)ipm->peer, pack, len); |
| return 0; |
| } |
| |
| /* MS-originated GTP1-U packet, needs to be sent via TUN device */ |
| static int encaps_tun(struct pdp_t *pdp, void *pack, unsigned len) |
| { |
| struct iphdr *iph = (struct iphdr *)pack; |
| struct ip6_hdr *ip6h = (struct ip6_hdr *)pack; |
| struct tun_t *tun = (struct tun_t *)pdp->ipif; |
| struct apn_ctx *apn = tun->priv; |
| char straddr[INET6_ADDRSTRLEN]; |
| struct ippoolm_t *peer; |
| uint8_t pref_offset; |
| |
| OSMO_ASSERT(tun); |
| OSMO_ASSERT(apn); |
| |
| LOGPPDP(LOGL_DEBUG, pdp, "Packet received on APN(%s): forwarding to tun %s\n", apn->cfg.name, tun->devname); |
| |
| switch (iph->version) { |
| case 6: |
| peer = pdp_get_peer_ipv(pdp, true); |
| if (!peer) { |
| LOGPPDP(LOGL_ERROR, pdp, "Packet from MS IPv6 with unassigned EUA: %s\n", |
| osmo_hexdump(pack, len)); |
| return -1; |
| } |
| |
| /* Validate packet comes from IPaddr assigned to the pdp ctx. |
| If packet is a LL addr, then EUA is in the lower 64 bits, |
| otherwise it's used as the 64 prefix */ |
| pref_offset = IN6_IS_ADDR_LINKLOCAL(&ip6h->ip6_src) ? 8 : 0; |
| if (memcmp(((uint8_t*)&ip6h->ip6_src) + pref_offset, &peer->addr.v6, 8)) { |
| LOGPPDP(LOGL_ERROR, pdp, "Packet from MS using unassigned src IPv6: %s\n", |
| inet_ntop(AF_INET6, &ip6h->ip6_src, straddr, sizeof(straddr))); |
| return -1; |
| } |
| |
| /* daddr: all-routers multicast addr */ |
| if (IN6_ARE_ADDR_EQUAL(&ip6h->ip6_dst, &all_router_mcast_addr)) |
| return handle_router_mcast(pdp->gsn, pdp, &peer->addr.v6, |
| &apn->v6_lladdr, pack, len); |
| break; |
| case 4: |
| peer = pdp_get_peer_ipv(pdp, false); |
| if (!peer) { |
| LOGPPDP(LOGL_ERROR, pdp, "Packet from MS IPv4 with unassigned EUA: %s\n", |
| osmo_hexdump(pack, len)); |
| return -1; |
| } |
| |
| /* Validate packet comes from IPaddr assigned to the pdp ctx */ |
| if (memcmp(&iph->saddr, &peer->addr.v4, sizeof(peer->addr.v4))) { |
| LOGPPDP(LOGL_ERROR, pdp, "Packet from MS using unassigned src IPv4: %s\n", |
| inet_ntop(AF_INET, &iph->saddr, straddr, sizeof(straddr))); |
| return -1; |
| } |
| break; |
| default: |
| LOGPPDP(LOGL_ERROR, pdp, "Packet from MS is neither IPv4 nor IPv6: %s\n", |
| osmo_hexdump(pack, len)); |
| return -1; |
| } |
| return tun_encaps((struct tun_t *)pdp->ipif, pack, len); |
| } |
| |
| /* callback for tun device osmocom select loop integration */ |
| static int ggsn_tun_fd_cb(struct osmo_fd *fd, unsigned int what) |
| { |
| struct apn_ctx *apn = fd->data; |
| |
| OSMO_ASSERT(what & OSMO_FD_READ); |
| |
| return tun_decaps(apn->tun.tun); |
| } |
| |
| /* callback for libgtp osmocom select loop integration */ |
| static int ggsn_gtp_fd_cb(struct osmo_fd *fd, unsigned int what) |
| { |
| struct ggsn_ctx *ggsn = fd->data; |
| int rc; |
| |
| OSMO_ASSERT(what & OSMO_FD_READ); |
| |
| switch (fd->priv_nr) { |
| case 0: |
| rc = gtp_decaps0(ggsn->gsn); |
| break; |
| case 1: |
| rc = gtp_decaps1c(ggsn->gsn); |
| break; |
| case 2: |
| rc = gtp_decaps1u(ggsn->gsn); |
| break; |
| default: |
| OSMO_ASSERT(0); |
| break; |
| } |
| return rc; |
| } |
| |
| /* libgtp callback for confirmations */ |
| static int cb_conf(int type, int cause, struct pdp_t *pdp, void *cbp) |
| { |
| struct sgsn_peer *sgsn; |
| int rc = 0; |
| |
| if (cause == EOF) |
| LOGP(DGGSN, LOGL_NOTICE, "libgtp EOF (type=%u, pdp=%p, cbp=%p)\n", |
| type, pdp, cbp); |
| |
| switch (type) { |
| case GTP_DELETE_PDP_REQ: |
| /* Remark: We actually never reach this path nowadays because |
| only place where we call gtp_delete_context_req2() is during |
| ggsn_close_one_pdp() path, and in that case we free all pdp |
| contexts immediatelly without waiting for confirmation |
| (through gtp_freepdp_teardown()) since we want to tear down |
| the whole APN anyways. As a result, DeleteCtxResponse will |
| never reach here since it will be dropped at some point in |
| lower layers in the Rx path. This code is nevertheless left |
| here in order to ease future developent and avoid possible |
| future memleaks once more scenarios where GGSN sends a |
| DeleteCtxRequest are introduced. */ |
| if (pdp) |
| rc = gtp_freepdp(pdp->gsn, pdp); |
| break; |
| case GTP_ECHO_REQ: |
| sgsn = (struct sgsn_peer *)cbp; |
| sgsn_peer_echo_resp(sgsn, cause == EOF); |
| break; |
| } |
| return rc; |
| } |
| |
| static int cb_recovery3(struct gsn_t *gsn, struct sockaddr_in *peer, struct pdp_t *pdp, uint8_t recovery) |
| { |
| struct ggsn_ctx *ggsn = (struct ggsn_ctx *)gsn->priv; |
| struct sgsn_peer *sgsn; |
| |
| sgsn = ggsn_find_sgsn(ggsn, &peer->sin_addr); |
| if (!sgsn) { |
| LOGPGGSN(LOGL_NOTICE, ggsn, "Received Recovery IE for unknown SGSN (no PDP contexts active)\n"); |
| return -EINVAL; |
| } |
| |
| return sgsn_peer_handle_recovery(sgsn, pdp, recovery); |
| } |
| |
| /* Start a given GGSN */ |
| int ggsn_start(struct ggsn_ctx *ggsn) |
| { |
| struct apn_ctx *apn; |
| int rc; |
| |
| if (ggsn->started) |
| return 0; |
| |
| LOGPGGSN(LOGL_INFO, ggsn, "Starting GGSN\n"); |
| |
| /* Start libgtp listener */ |
| if (gtp_new(&ggsn->gsn, ggsn->cfg.state_dir, &ggsn->cfg.listen_addr.v4, GTP_MODE_GGSN)) { |
| LOGPGGSN(LOGL_ERROR, ggsn, "Failed to create GTP: %s\n", strerror(errno)); |
| return -1; |
| } |
| ggsn->gsn->priv = ggsn; |
| |
| /* patch in different addresses to use (in case we're behind NAT, the listen |
| * address is different from what we advertise externally) */ |
| if (ggsn->cfg.gtpc_addr.v4.s_addr) |
| ggsn->gsn->gsnc = ggsn->cfg.gtpc_addr.v4; |
| |
| if (ggsn->cfg.gtpu_addr.v4.s_addr) |
| ggsn->gsn->gsnu = ggsn->cfg.gtpu_addr.v4; |
| |
| /* Register File Descriptors */ |
| osmo_fd_setup(&ggsn->gtp_fd0, ggsn->gsn->fd0, OSMO_FD_READ, ggsn_gtp_fd_cb, ggsn, 0); |
| rc = osmo_fd_register(&ggsn->gtp_fd0); |
| OSMO_ASSERT(rc == 0); |
| |
| osmo_fd_setup(&ggsn->gtp_fd1c, ggsn->gsn->fd1c, OSMO_FD_READ, ggsn_gtp_fd_cb, ggsn, 1); |
| rc = osmo_fd_register(&ggsn->gtp_fd1c); |
| OSMO_ASSERT(rc == 0); |
| |
| osmo_fd_setup(&ggsn->gtp_fd1u, ggsn->gsn->fd1u, OSMO_FD_READ, ggsn_gtp_fd_cb, ggsn, 2); |
| rc = osmo_fd_register(&ggsn->gtp_fd1u); |
| OSMO_ASSERT(rc == 0); |
| |
| gtp_set_cb_data_ind(ggsn->gsn, encaps_tun); |
| gtp_set_cb_delete_context(ggsn->gsn, delete_context); |
| gtp_set_cb_create_context_ind(ggsn->gsn, create_context_ind); |
| gtp_set_cb_conf(ggsn->gsn, cb_conf); |
| gtp_set_cb_recovery3(ggsn->gsn, cb_recovery3); |
| |
| LOGPGGSN(LOGL_NOTICE, ggsn, "Successfully started\n"); |
| ggsn->started = true; |
| |
| llist_for_each_entry(apn, &ggsn->apn_list, list) |
| apn_start(apn); |
| |
| return 0; |
| } |
| |
| /* Stop a given GGSN */ |
| int ggsn_stop(struct ggsn_ctx *ggsn) |
| { |
| struct apn_ctx *apn; |
| |
| if (!ggsn->started) |
| return 0; |
| |
| /* iterate over all APNs and stop them */ |
| llist_for_each_entry(apn, &ggsn->apn_list, list) |
| apn_stop(apn); |
| |
| osmo_fd_unregister(&ggsn->gtp_fd1u); |
| osmo_fd_unregister(&ggsn->gtp_fd1c); |
| osmo_fd_unregister(&ggsn->gtp_fd0); |
| |
| if (ggsn->gsn) { |
| gtp_free(ggsn->gsn); |
| ggsn->gsn = NULL; |
| } |
| |
| ggsn->started = false; |
| return 0; |
| } |