Harald Welte | f736559 | 2020-04-15 21:48:45 +0200 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #include <unistd.h> |
| 3 | #include <stdint.h> |
| 4 | #include <stdbool.h> |
| 5 | #include <stdlib.h> |
| 6 | #include <string.h> |
| 7 | #include <stdio.h> |
| 8 | #include <assert.h> |
| 9 | #include <errno.h> |
| 10 | |
| 11 | #include <pthread.h> |
| 12 | |
| 13 | #include <osmocom/core/linuxlist.h> |
| 14 | #include <osmocom/core/talloc.h> |
| 15 | #include <osmocom/core/logging.h> |
| 16 | |
| 17 | #include "internal.h" |
| 18 | |
| 19 | #define LOGT(t, lvl, fmt, args ...) \ |
| 20 | LOGP(DGT, lvl, "%s: " fmt, (t)->name, ## args) |
| 21 | |
| 22 | /*********************************************************************** |
| 23 | * GTP Tunnel |
| 24 | ***********************************************************************/ |
| 25 | struct gtp_tunnel *gtp_tunnel_alloc(struct gtp_daemon *d, const struct gtp_tunnel_params *cpars) |
| 26 | { |
| 27 | struct gtp_tunnel *t; |
| 28 | |
| 29 | t = talloc_zero(d, struct gtp_tunnel); |
| 30 | if (!t) |
| 31 | goto out_unlock; |
| 32 | t->d = d; |
| 33 | t->name = talloc_asprintf(t, "%s-R%08x-T%08x", cpars->tun_name, cpars->rx_teid, cpars->tx_teid); |
| 34 | t->tun_dev = tun_device_find_or_create(d, cpars->tun_name, cpars->tun_netns_name); |
| 35 | if (!t->tun_dev) { |
| 36 | LOGT(t, LOGL_ERROR, "Cannot find or create tun device %s\n", cpars->tun_name); |
| 37 | goto out_free; |
| 38 | } |
| 39 | |
| 40 | t->gtp_ep = gtp_endpoint_find_or_create(d, &cpars->local_udp); |
| 41 | if (!t->gtp_ep) { |
| 42 | LOGT(t, LOGL_ERROR, "Cannot find or create GTP endpoint\n"); |
| 43 | goto out_tun; |
| 44 | } |
| 45 | |
| 46 | pthread_rwlock_wrlock(&d->rwlock); |
| 47 | /* check if we already have a tunnel with same Rx-TEID + endpoint */ |
| 48 | if (_gtp_tunnel_find_r(d, cpars->rx_teid, t->gtp_ep)) { |
| 49 | LOGT(t, LOGL_ERROR, "Error: We already have a tunnel for RxTEID 0x%08x " |
| 50 | "on this endpoint (%s)\n", cpars->rx_teid, t->gtp_ep->name); |
| 51 | goto out_ep; |
| 52 | } |
| 53 | |
| 54 | /* FIXME: check if we already have a tunnel with same Tx-TEID + peer */ |
| 55 | /* FIXME: check if we already have a tunnel with same tun + EUA + filter */ |
| 56 | |
| 57 | t->rx_teid = cpars->rx_teid; |
| 58 | t->tx_teid = cpars->tx_teid; |
| 59 | memcpy(&t->user_addr, &cpars->user_addr, sizeof(t->user_addr)); |
| 60 | memcpy(&t->remote_udp, &cpars->remote_udp, sizeof(t->remote_udp)); |
| 61 | |
| 62 | if (netdev_add_addr(t->tun_dev->nl, t->tun_dev->ifindex, &t->user_addr) < 0) { |
| 63 | LOGT(t, LOGL_ERROR, "Cannot add user addr to tun device: %s\n", |
| 64 | strerror(errno)); |
| 65 | } |
| 66 | |
| 67 | /* TODO: hash table? */ |
| 68 | llist_add_tail(&t->list, &d->gtp_tunnels); |
| 69 | pthread_rwlock_unlock(&d->rwlock); |
| 70 | LOGT(t, LOGL_NOTICE, "Created\n"); |
| 71 | |
| 72 | return t; |
| 73 | |
| 74 | out_ep: |
| 75 | _gtp_endpoint_release(t->gtp_ep); |
| 76 | out_tun: |
| 77 | _tun_device_release(t->tun_dev); |
| 78 | out_free: |
| 79 | talloc_free(t); |
| 80 | out_unlock: |
| 81 | pthread_rwlock_unlock(&d->rwlock); |
| 82 | |
| 83 | return NULL; |
| 84 | } |
| 85 | |
Harald Welte | f23abd7 | 2020-04-20 12:09:32 +0200 | [diff] [blame] | 86 | #if 0 |
Harald Welte | f736559 | 2020-04-15 21:48:45 +0200 | [diff] [blame] | 87 | /* find tunnel by R(x_teid), T(x_teid) + A(ddr) */ |
| 88 | static struct gtp_tunnel * |
| 89 | _gtp_tunnel_find_rta(struct gtp_daemon *d, uint32_t rx_teid, uint32_t tx_teid, |
| 90 | const struct sockaddr_storage *user_addr) |
| 91 | { |
| 92 | struct gtp_tunnel *t; |
| 93 | llist_for_each_entry(t, &d->gtp_tunnels, list) { |
| 94 | if (t->rx_teid == rx_teid && t->tx_teid == tx_teid && |
| 95 | sockaddr_equals((struct sockaddr *) &t->user_addr, (struct sockaddr *)user_addr)) |
| 96 | return t; |
| 97 | } |
| 98 | return NULL; |
| 99 | } |
Harald Welte | f23abd7 | 2020-04-20 12:09:32 +0200 | [diff] [blame] | 100 | #endif |
Harald Welte | f736559 | 2020-04-15 21:48:45 +0200 | [diff] [blame] | 101 | |
| 102 | /* find tunnel by R(x_teid) + optionally local endpoint */ |
| 103 | struct gtp_tunnel * |
| 104 | _gtp_tunnel_find_r(struct gtp_daemon *d, uint32_t rx_teid, struct gtp_endpoint *ep) |
| 105 | { |
| 106 | struct gtp_tunnel *t; |
| 107 | llist_for_each_entry(t, &d->gtp_tunnels, list) { |
| 108 | if (t->rx_teid == rx_teid) { |
| 109 | if (!ep) |
| 110 | return t; |
| 111 | if (t->gtp_ep == ep) |
| 112 | return t; |
| 113 | } |
| 114 | } |
| 115 | return NULL; |
| 116 | } |
| 117 | |
| 118 | /* UNLOCKED find tunnel by tun + EUA ip (+proto/port) */ |
| 119 | struct gtp_tunnel * |
| 120 | _gtp_tunnel_find_eua(struct tun_device *tun, const struct sockaddr *sa, uint8_t proto) |
| 121 | { |
| 122 | struct gtp_daemon *d = tun->d; |
| 123 | struct gtp_tunnel *t; |
| 124 | |
| 125 | llist_for_each_entry(t, &d->gtp_tunnels, list) { |
| 126 | /* TODO: Find best matching filter */ |
| 127 | if (t->tun_dev == tun && sockaddr_equals(sa, (struct sockaddr *) &t->user_addr)) |
| 128 | return t; |
| 129 | } |
| 130 | return NULL; |
| 131 | } |
| 132 | |
| 133 | /* UNLOCKED destroy of tunnel; drops references to EP + TUN */ |
| 134 | void _gtp_tunnel_destroy(struct gtp_tunnel *t) |
| 135 | { |
| 136 | LOGT(t, LOGL_NOTICE, "Destroying\n"); |
| 137 | /* talloc is not thread safe, all alloc/free must come from main thread */ |
| 138 | ASSERT_MAIN_THREAD(t->d); |
| 139 | |
| 140 | if (netdev_del_addr(t->tun_dev->nl, t->tun_dev->ifindex, &t->user_addr) < 0) |
| 141 | LOGT(t, LOGL_ERROR, "Cannot remove user address: %s\n", strerror(errno)); |
| 142 | |
| 143 | llist_del(&t->list); |
| 144 | |
| 145 | /* drop reference to endpoint + tun */ |
| 146 | _gtp_endpoint_release(t->gtp_ep); |
| 147 | _tun_device_release(t->tun_dev); |
| 148 | |
| 149 | talloc_free(t); |
| 150 | } |
| 151 | |
| 152 | bool gtp_tunnel_destroy(struct gtp_daemon *d, const struct sockaddr_storage *bind_addr, uint32_t rx_teid) |
| 153 | { |
| 154 | struct gtp_endpoint *ep; |
| 155 | bool rc = false; |
| 156 | |
| 157 | pthread_rwlock_wrlock(&d->rwlock); |
| 158 | /* find endpoint for bind_addr */ |
| 159 | ep = _gtp_endpoint_find(d, bind_addr); |
| 160 | if (ep) { |
| 161 | /* find tunnel for rx TEID within endpoint */ |
| 162 | struct gtp_tunnel *t = _gtp_tunnel_find_r(d, rx_teid, ep); |
| 163 | if (t) { |
| 164 | _gtp_tunnel_destroy(t); |
| 165 | rc = true; |
| 166 | } |
| 167 | } |
| 168 | pthread_rwlock_unlock(&d->rwlock); |
| 169 | |
| 170 | return rc; |
| 171 | } |