Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1 | /* NS-over-IP proxy */ |
| 2 | |
| 3 | /* (C) 2010 by Harald Welte <laforge@gnumonks.org> |
| 4 | * (C) 2010-2013 by On-Waves |
| 5 | * (C) 2013 by Holger Hans Peter Freyther |
| 6 | * All Rights Reserved |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU Affero General Public License as published by |
| 10 | * the Free Software Foundation; either version 3 of the License, or |
| 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU Affero General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Affero General Public License |
| 19 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 20 | * |
| 21 | */ |
| 22 | |
| 23 | #include <unistd.h> |
| 24 | #include <stdio.h> |
| 25 | #include <stdlib.h> |
| 26 | #include <string.h> |
| 27 | #include <getopt.h> |
| 28 | #include <errno.h> |
| 29 | #include <sys/fcntl.h> |
| 30 | #include <sys/stat.h> |
| 31 | #include <arpa/inet.h> |
| 32 | #include <time.h> |
| 33 | |
| 34 | #include <osmocom/core/talloc.h> |
| 35 | #include <osmocom/core/select.h> |
| 36 | #include <osmocom/core/rate_ctr.h> |
| 37 | #include <osmocom/core/stats.h> |
| 38 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 39 | #include <osmocom/gprs/gprs_ns2.h> |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 40 | #include <osmocom/gprs/gprs_bssgp.h> |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 41 | #include <osmocom/gprs/gprs_bssgp_bss.h> |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 42 | |
| 43 | #include <osmocom/gsm/gsm_utils.h> |
| 44 | |
| 45 | #include <osmocom/sgsn/signal.h> |
| 46 | #include <osmocom/sgsn/debug.h> |
| 47 | #include <osmocom/sgsn/gprs_gb_parse.h> |
| 48 | #include <osmocom/sgsn/gb_proxy.h> |
| 49 | |
| 50 | #include <osmocom/sgsn/gprs_llc.h> |
| 51 | #include <osmocom/gsm/protocol/gsm_04_08_gprs.h> |
| 52 | #include <osmocom/sgsn/gprs_utils.h> |
| 53 | |
| 54 | extern void *tall_sgsn_ctx; |
| 55 | |
| 56 | static const struct rate_ctr_desc global_ctr_description[] = { |
| 57 | { "inv-bvci", "Invalid BVC Identifier " }, |
| 58 | { "inv-lai", "Invalid Location Area Identifier" }, |
| 59 | { "inv-rai", "Invalid Routing Area Identifier " }, |
| 60 | { "inv-nsei", "No BVC established for NSEI " }, |
| 61 | { "proto-err:bss", "BSSGP protocol error (BSS )" }, |
| 62 | { "proto-err:sgsn", "BSSGP protocol error (SGSN)" }, |
| 63 | { "not-supp:bss", "Feature not supported (BSS )" }, |
| 64 | { "not-supp:sgsn", "Feature not supported (SGSN)" }, |
| 65 | { "restart:sgsn", "Restarted RESET procedure (SGSN)" }, |
| 66 | { "tx-err:sgsn", "NS Transmission error (SGSN)" }, |
| 67 | { "error", "Other error " }, |
| 68 | { "mod-peer-err", "Patch error: no peer " }, |
| 69 | }; |
| 70 | |
| 71 | static const struct rate_ctr_group_desc global_ctrg_desc = { |
| 72 | .group_name_prefix = "gbproxy:global", |
| 73 | .group_description = "GBProxy Global Statistics", |
| 74 | .num_ctr = ARRAY_SIZE(global_ctr_description), |
| 75 | .ctr_desc = global_ctr_description, |
| 76 | .class_id = OSMO_STATS_CLASS_GLOBAL, |
| 77 | }; |
| 78 | |
| 79 | static int gbprox_relay2peer(struct msgb *old_msg, struct gbproxy_peer *peer, |
Daniel Willmann | 35f7d33 | 2020-11-03 21:11:45 +0100 | [diff] [blame] | 80 | uint16_t ns_bvci); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 81 | static int gbprox_relay2sgsn(struct gbproxy_config *cfg, struct msgb *old_msg, |
| 82 | uint16_t ns_bvci, uint16_t sgsn_nsei); |
| 83 | static void gbproxy_reset_imsi_acquisition(struct gbproxy_link_info* link_info); |
| 84 | |
| 85 | static int check_peer_nsei(struct gbproxy_peer *peer, uint16_t nsei) |
| 86 | { |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 87 | OSMO_ASSERT(peer->nse); |
| 88 | |
| 89 | if (peer->nse->nsei != nsei) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 90 | LOGP(DGPRS, LOGL_NOTICE, "Peer entry doesn't match current NSEI " |
| 91 | "BVCI=%u via NSEI=%u (expected NSEI=%u)\n", |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 92 | peer->bvci, nsei, peer->nse->nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 93 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_INV_NSEI]); |
| 94 | return 0; |
| 95 | } |
| 96 | |
| 97 | return 1; |
| 98 | } |
| 99 | |
| 100 | /* strip off the NS header */ |
| 101 | static void strip_ns_hdr(struct msgb *msg) |
| 102 | { |
| 103 | int strip_len = msgb_bssgph(msg) - msg->data; |
| 104 | msgb_pull(msg, strip_len); |
| 105 | } |
| 106 | |
| 107 | /* Transmit Chapter 9.2.10 Identity Request */ |
| 108 | static void gprs_put_identity_req(struct msgb *msg, uint8_t id_type) |
| 109 | { |
| 110 | struct gsm48_hdr *gh; |
| 111 | |
| 112 | id_type &= GSM_MI_TYPE_MASK; |
| 113 | |
| 114 | gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1); |
| 115 | gh->proto_discr = GSM48_PDISC_MM_GPRS; |
| 116 | gh->msg_type = GSM48_MT_GMM_ID_REQ; |
| 117 | gh->data[0] = id_type; |
| 118 | } |
| 119 | |
| 120 | /* Transmit Chapter 9.4.6.2 Detach Accept (mobile originated detach) */ |
| 121 | static void gprs_put_mo_detach_acc(struct msgb *msg) |
| 122 | { |
| 123 | struct gsm48_hdr *gh; |
| 124 | |
| 125 | gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1); |
| 126 | gh->proto_discr = GSM48_PDISC_MM_GPRS; |
| 127 | gh->msg_type = GSM48_MT_GMM_DETACH_ACK; |
| 128 | gh->data[0] = 0; /* no force to standby */ |
| 129 | } |
| 130 | |
| 131 | static void gprs_push_llc_ui(struct msgb *msg, |
| 132 | int is_uplink, unsigned sapi, unsigned nu) |
| 133 | { |
| 134 | const uint8_t e_bit = 0; |
| 135 | const uint8_t pm_bit = 1; |
| 136 | const uint8_t cr_bit = is_uplink ? 0 : 1; |
| 137 | uint8_t *llc; |
| 138 | uint8_t *fcs_field; |
| 139 | uint32_t fcs; |
| 140 | |
| 141 | nu &= 0x01ff; /* 9 Bit */ |
| 142 | |
| 143 | llc = msgb_push(msg, 3); |
| 144 | llc[0] = (cr_bit << 6) | (sapi & 0x0f); |
| 145 | llc[1] = 0xc0 | (nu >> 6); /* UI frame */ |
| 146 | llc[2] = (nu << 2) | ((e_bit & 1) << 1) | (pm_bit & 1); |
| 147 | |
| 148 | fcs = gprs_llc_fcs(llc, msgb_length(msg)); |
| 149 | fcs_field = msgb_put(msg, 3); |
| 150 | fcs_field[0] = (uint8_t)(fcs >> 0); |
| 151 | fcs_field[1] = (uint8_t)(fcs >> 8); |
| 152 | fcs_field[2] = (uint8_t)(fcs >> 16); |
| 153 | } |
| 154 | |
| 155 | static void gprs_push_bssgp_dl_unitdata(struct msgb *msg, |
| 156 | uint32_t tlli) |
| 157 | { |
| 158 | struct bssgp_ud_hdr *budh; |
| 159 | uint8_t *llc = msgb_data(msg); |
| 160 | size_t llc_size = msgb_length(msg); |
| 161 | const size_t llc_ie_hdr_size = 3; |
| 162 | const uint8_t qos_profile[] = {0x00, 0x50, 0x20}; /* hard-coded */ |
| 163 | const uint8_t lifetime[] = {0x02, 0x58}; /* 6s hard-coded */ |
| 164 | |
| 165 | const size_t bssgp_overhead = sizeof(*budh) + |
| 166 | TVLV_GROSS_LEN(sizeof(lifetime)) + llc_ie_hdr_size; |
| 167 | uint8_t *ie; |
| 168 | uint32_t tlli_be = htonl(tlli); |
| 169 | |
| 170 | budh = (struct bssgp_ud_hdr *)msgb_push(msg, bssgp_overhead); |
| 171 | |
| 172 | budh->pdu_type = BSSGP_PDUT_DL_UNITDATA; |
| 173 | memcpy(&budh->tlli, &tlli_be, sizeof(budh->tlli)); |
| 174 | memcpy(&budh->qos_profile, qos_profile, sizeof(budh->qos_profile)); |
| 175 | |
| 176 | ie = budh->data; |
| 177 | tvlv_put(ie, BSSGP_IE_PDU_LIFETIME, sizeof(lifetime), lifetime); |
| 178 | ie += TVLV_GROSS_LEN(sizeof(lifetime)); |
| 179 | |
| 180 | /* Note: Add alignment before the LLC IE if inserting other IE */ |
| 181 | |
| 182 | *(ie++) = BSSGP_IE_LLC_PDU; |
| 183 | *(ie++) = llc_size / 256; |
| 184 | *(ie++) = llc_size % 256; |
| 185 | |
| 186 | OSMO_ASSERT(ie == llc); |
| 187 | |
| 188 | msgb_bssgph(msg) = (uint8_t *)budh; |
| 189 | msgb_tlli(msg) = tlli; |
| 190 | } |
| 191 | |
| 192 | /* update peer according to the BSS message */ |
| 193 | static void gbprox_update_current_raid(uint8_t *raid_enc, |
| 194 | struct gbproxy_peer *peer, |
| 195 | const char *log_text) |
| 196 | { |
| 197 | struct gbproxy_patch_state *state = &peer->patch_state; |
| 198 | const struct osmo_plmn_id old_plmn = state->local_plmn; |
| 199 | struct gprs_ra_id raid; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 200 | OSMO_ASSERT(peer->nse); |
| 201 | struct gbproxy_config *cfg = peer->nse->cfg; |
| 202 | OSMO_ASSERT(cfg); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 203 | |
| 204 | if (!raid_enc) |
| 205 | return; |
| 206 | |
| 207 | gsm48_parse_ra(&raid, raid_enc); |
| 208 | |
| 209 | /* save source side MCC/MNC */ |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 210 | if (!cfg->core_plmn.mcc || raid.mcc == cfg->core_plmn.mcc) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 211 | state->local_plmn.mcc = 0; |
| 212 | } else { |
| 213 | state->local_plmn.mcc = raid.mcc; |
| 214 | } |
| 215 | |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 216 | if (!cfg->core_plmn.mnc |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 217 | || !osmo_mnc_cmp(raid.mnc, raid.mnc_3_digits, |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 218 | cfg->core_plmn.mnc, cfg->core_plmn.mnc_3_digits)) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 219 | state->local_plmn.mnc = 0; |
| 220 | state->local_plmn.mnc_3_digits = false; |
| 221 | } else { |
| 222 | state->local_plmn.mnc = raid.mnc; |
| 223 | state->local_plmn.mnc_3_digits = raid.mnc_3_digits; |
| 224 | } |
| 225 | |
| 226 | if (osmo_plmn_cmp(&old_plmn, &state->local_plmn)) |
| 227 | LOGP(DGPRS, LOGL_NOTICE, |
| 228 | "Patching RAID %sactivated, msg: %s, " |
| 229 | "local: %s, core: %s\n", |
| 230 | state->local_plmn.mcc || state->local_plmn.mnc ? |
| 231 | "" : "de", |
| 232 | log_text, |
| 233 | osmo_plmn_name(&state->local_plmn), |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 234 | osmo_plmn_name2(&cfg->core_plmn)); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 235 | } |
| 236 | |
| 237 | uint32_t gbproxy_make_bss_ptmsi(struct gbproxy_peer *peer, |
| 238 | uint32_t sgsn_ptmsi) |
| 239 | { |
| 240 | uint32_t bss_ptmsi; |
| 241 | int max_retries = 23, rc = 0; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 242 | if (!peer->nse->cfg->patch_ptmsi) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 243 | bss_ptmsi = sgsn_ptmsi; |
| 244 | } else { |
| 245 | do { |
| 246 | rc = osmo_get_rand_id((uint8_t *) &bss_ptmsi, sizeof(bss_ptmsi)); |
| 247 | if (rc < 0) { |
| 248 | bss_ptmsi = GSM_RESERVED_TMSI; |
| 249 | break; |
| 250 | } |
| 251 | |
| 252 | bss_ptmsi = bss_ptmsi | GSM23003_TMSI_SGSN_MASK; |
| 253 | |
| 254 | if (gbproxy_link_info_by_ptmsi(peer, bss_ptmsi)) |
| 255 | bss_ptmsi = GSM_RESERVED_TMSI; |
| 256 | } while (bss_ptmsi == GSM_RESERVED_TMSI && max_retries--); |
| 257 | } |
| 258 | |
| 259 | if (bss_ptmsi == GSM_RESERVED_TMSI) |
| 260 | LOGP(DGPRS, LOGL_ERROR, "Failed to allocate a BSS P-TMSI: %d (%s)\n", rc, strerror(-rc)); |
| 261 | |
| 262 | return bss_ptmsi; |
| 263 | } |
| 264 | |
| 265 | uint32_t gbproxy_make_sgsn_tlli(struct gbproxy_peer *peer, |
| 266 | struct gbproxy_link_info *link_info, |
| 267 | uint32_t bss_tlli) |
| 268 | { |
| 269 | uint32_t sgsn_tlli; |
| 270 | int max_retries = 23, rc = 0; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 271 | if (!peer->nse->cfg->patch_ptmsi) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 272 | sgsn_tlli = bss_tlli; |
| 273 | } else if (link_info->sgsn_tlli.ptmsi != GSM_RESERVED_TMSI && |
| 274 | gprs_tlli_type(bss_tlli) == TLLI_FOREIGN) { |
| 275 | sgsn_tlli = gprs_tmsi2tlli(link_info->sgsn_tlli.ptmsi, |
| 276 | TLLI_FOREIGN); |
| 277 | } else if (link_info->sgsn_tlli.ptmsi != GSM_RESERVED_TMSI && |
| 278 | gprs_tlli_type(bss_tlli) == TLLI_LOCAL) { |
| 279 | sgsn_tlli = gprs_tmsi2tlli(link_info->sgsn_tlli.ptmsi, |
| 280 | TLLI_LOCAL); |
| 281 | } else { |
| 282 | do { |
| 283 | /* create random TLLI, 0b01111xxx... */ |
| 284 | rc = osmo_get_rand_id((uint8_t *) &sgsn_tlli, sizeof(sgsn_tlli)); |
| 285 | if (rc < 0) { |
| 286 | sgsn_tlli = 0; |
| 287 | break; |
| 288 | } |
| 289 | |
| 290 | sgsn_tlli = (sgsn_tlli & 0x7fffffff) | 0x78000000; |
| 291 | |
| 292 | if (gbproxy_link_info_by_any_sgsn_tlli(peer, sgsn_tlli)) |
| 293 | sgsn_tlli = 0; |
| 294 | } while (!sgsn_tlli && max_retries--); |
| 295 | } |
| 296 | |
| 297 | if (!sgsn_tlli) |
| 298 | LOGP(DGPRS, LOGL_ERROR, "Failed to allocate an SGSN TLLI: %d (%s)\n", rc, strerror(-rc)); |
| 299 | |
| 300 | return sgsn_tlli; |
| 301 | } |
| 302 | |
| 303 | void gbproxy_reset_link(struct gbproxy_link_info *link_info) |
| 304 | { |
| 305 | gbproxy_reset_imsi_acquisition(link_info); |
| 306 | } |
| 307 | |
| 308 | /* Returns != 0 iff IMSI acquisition was in progress */ |
| 309 | static int gbproxy_restart_imsi_acquisition(struct gbproxy_link_info* link_info) |
| 310 | { |
| 311 | int in_progress = 0; |
| 312 | if (!link_info) |
| 313 | return 0; |
| 314 | |
| 315 | if (link_info->imsi_acq_pending) |
| 316 | in_progress = 1; |
| 317 | |
| 318 | gbproxy_link_info_discard_messages(link_info); |
| 319 | link_info->imsi_acq_pending = false; |
| 320 | |
| 321 | return in_progress; |
| 322 | } |
| 323 | |
| 324 | static void gbproxy_reset_imsi_acquisition(struct gbproxy_link_info* link_info) |
| 325 | { |
| 326 | gbproxy_restart_imsi_acquisition(link_info); |
| 327 | link_info->vu_gen_tx_bss = GBPROXY_INIT_VU_GEN_TX; |
| 328 | } |
| 329 | |
| 330 | /* Got identity response with IMSI, assuming the request had |
| 331 | * been generated by the gbproxy */ |
| 332 | static int gbproxy_flush_stored_messages(struct gbproxy_peer *peer, |
| 333 | time_t now, |
| 334 | struct gbproxy_link_info* link_info) |
| 335 | { |
| 336 | int rc; |
| 337 | struct msgb *stored_msg; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 338 | OSMO_ASSERT(peer->nse); |
| 339 | struct gbproxy_config *cfg = peer->nse->cfg; |
| 340 | OSMO_ASSERT(cfg); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 341 | |
| 342 | /* Patch and flush stored messages towards the SGSN */ |
| 343 | while ((stored_msg = msgb_dequeue_count(&link_info->stored_msgs, |
| 344 | &link_info->stored_msgs_len))) { |
| 345 | struct gprs_gb_parse_context tmp_parse_ctx = {0}; |
| 346 | tmp_parse_ctx.to_bss = 0; |
| 347 | tmp_parse_ctx.peer_nsei = msgb_nsei(stored_msg); |
| 348 | int len_change = 0; |
| 349 | |
| 350 | gprs_gb_parse_bssgp(msgb_bssgph(stored_msg), |
| 351 | msgb_bssgp_len(stored_msg), |
| 352 | &tmp_parse_ctx); |
| 353 | gbproxy_patch_bssgp(stored_msg, msgb_bssgph(stored_msg), |
| 354 | msgb_bssgp_len(stored_msg), |
| 355 | peer, link_info, &len_change, |
| 356 | &tmp_parse_ctx); |
| 357 | |
| 358 | rc = gbproxy_update_link_state_after(peer, link_info, now, |
| 359 | &tmp_parse_ctx); |
| 360 | if (rc == 1) { |
| 361 | LOGP(DLLC, LOGL_NOTICE, "link_info deleted while flushing stored messages\n"); |
| 362 | msgb_free(stored_msg); |
| 363 | return -1; |
| 364 | } |
| 365 | |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 366 | rc = gbprox_relay2sgsn(cfg, stored_msg, |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 367 | msgb_bvci(stored_msg), link_info->sgsn_nsei); |
| 368 | |
| 369 | if (rc < 0) |
| 370 | LOGP(DLLC, LOGL_ERROR, |
| 371 | "NSEI=%d(BSS) failed to send stored message " |
| 372 | "(%s)\n", |
| 373 | tmp_parse_ctx.peer_nsei, |
| 374 | tmp_parse_ctx.llc_msg_name ? |
| 375 | tmp_parse_ctx.llc_msg_name : "BSSGP"); |
| 376 | msgb_free(stored_msg); |
| 377 | } |
| 378 | |
| 379 | return 0; |
| 380 | } |
| 381 | |
| 382 | static int gbproxy_gsm48_to_peer(struct gbproxy_peer *peer, |
| 383 | struct gbproxy_link_info* link_info, |
| 384 | uint16_t bvci, |
| 385 | struct msgb *msg /* Takes msg ownership */) |
| 386 | { |
| 387 | int rc; |
| 388 | |
| 389 | /* Workaround to avoid N(U) collisions and to enable a restart |
| 390 | * of the IMSI acquisition procedure. This will work unless the |
| 391 | * SGSN has an initial V(UT) within [256-32, 256+n_retries] |
| 392 | * (see GSM 04.64, 8.4.2). */ |
| 393 | gprs_push_llc_ui(msg, 0, GPRS_SAPI_GMM, link_info->vu_gen_tx_bss); |
| 394 | link_info->vu_gen_tx_bss = (link_info->vu_gen_tx_bss + 1) % 512; |
| 395 | |
| 396 | gprs_push_bssgp_dl_unitdata(msg, link_info->tlli.current); |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 397 | msg->l3h = msg->data; |
| 398 | |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 399 | rc = gbprox_relay2peer(msg, peer, bvci); |
| 400 | msgb_free(msg); |
| 401 | return rc; |
| 402 | } |
| 403 | |
| 404 | static void gbproxy_acquire_imsi(struct gbproxy_peer *peer, |
| 405 | struct gbproxy_link_info* link_info, |
| 406 | uint16_t bvci) |
| 407 | { |
| 408 | struct msgb *idreq_msg; |
| 409 | |
| 410 | /* Send IDENT REQ */ |
| 411 | idreq_msg = gsm48_msgb_alloc_name("GSM 04.08 ACQ IMSI"); |
| 412 | gprs_put_identity_req(idreq_msg, GSM_MI_TYPE_IMSI); |
| 413 | gbproxy_gsm48_to_peer(peer, link_info, bvci, idreq_msg); |
| 414 | } |
| 415 | |
| 416 | static void gbproxy_tx_detach_acc(struct gbproxy_peer *peer, |
| 417 | struct gbproxy_link_info* link_info, |
| 418 | uint16_t bvci) |
| 419 | { |
| 420 | struct msgb *detacc_msg; |
| 421 | |
| 422 | /* Send DETACH ACC */ |
| 423 | detacc_msg = gsm48_msgb_alloc_name("GSM 04.08 DET ACC"); |
| 424 | gprs_put_mo_detach_acc(detacc_msg); |
| 425 | gbproxy_gsm48_to_peer(peer, link_info, bvci, detacc_msg); |
| 426 | } |
| 427 | |
| 428 | /* Return != 0 iff msg still needs to be processed */ |
| 429 | static int gbproxy_imsi_acquisition(struct gbproxy_peer *peer, |
| 430 | struct msgb *msg, |
| 431 | time_t now, |
| 432 | struct gbproxy_link_info* link_info, |
| 433 | struct gprs_gb_parse_context *parse_ctx) |
| 434 | { |
| 435 | struct msgb *stored_msg; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 436 | OSMO_ASSERT(peer->nse); |
| 437 | struct gbproxy_config *cfg = peer->nse->cfg; |
| 438 | OSMO_ASSERT(cfg); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 439 | |
| 440 | if (!link_info) |
| 441 | return 1; |
| 442 | |
| 443 | if (!link_info->imsi_acq_pending && link_info->imsi_len > 0) |
| 444 | return 1; |
| 445 | |
| 446 | if (parse_ctx->g48_hdr) |
| 447 | switch (parse_ctx->g48_hdr->msg_type) |
| 448 | { |
| 449 | case GSM48_MT_GMM_RA_UPD_REQ: |
| 450 | case GSM48_MT_GMM_ATTACH_REQ: |
| 451 | if (gbproxy_restart_imsi_acquisition(link_info)) { |
| 452 | LOGP(DLLC, LOGL_INFO, |
| 453 | "NSEI=%d(BSS) IMSI acquisition was in progress " |
| 454 | "when receiving an %s.\n", |
| 455 | msgb_nsei(msg), parse_ctx->llc_msg_name); |
| 456 | } |
| 457 | break; |
| 458 | case GSM48_MT_GMM_DETACH_REQ: |
| 459 | /* Nothing has been sent to the SGSN yet */ |
| 460 | if (link_info->imsi_acq_pending) { |
| 461 | LOGP(DLLC, LOGL_INFO, |
| 462 | "NSEI=%d(BSS) IMSI acquisition was in progress " |
| 463 | "when receiving a DETACH_REQ.\n", |
| 464 | msgb_nsei(msg)); |
| 465 | } |
| 466 | if (!parse_ctx->invalidate_tlli) { |
| 467 | LOGP(DLLC, LOGL_INFO, |
| 468 | "NSEI=%d(BSS) IMSI not yet acquired, " |
| 469 | "faking a DETACH_ACC.\n", |
| 470 | msgb_nsei(msg)); |
| 471 | gbproxy_tx_detach_acc(peer, link_info, msgb_bvci(msg)); |
| 472 | parse_ctx->invalidate_tlli = 1; |
| 473 | } |
| 474 | gbproxy_reset_imsi_acquisition(link_info); |
| 475 | gbproxy_update_link_state_after(peer, link_info, now, |
| 476 | parse_ctx); |
| 477 | return 0; |
| 478 | } |
| 479 | |
| 480 | if (link_info->imsi_acq_pending && link_info->imsi_len > 0) { |
| 481 | int is_ident_resp = |
| 482 | parse_ctx->g48_hdr && |
| 483 | gsm48_hdr_pdisc(parse_ctx->g48_hdr) == GSM48_PDISC_MM_GPRS && |
| 484 | gsm48_hdr_msg_type(parse_ctx->g48_hdr) == GSM48_MT_GMM_ID_RESP; |
| 485 | |
| 486 | LOGP(DLLC, LOGL_DEBUG, |
| 487 | "NSEI=%d(BSS) IMSI acquisition succeeded, " |
| 488 | "flushing stored messages\n", |
| 489 | msgb_nsei(msg)); |
| 490 | /* The IMSI is now available. If flushing the messages fails, |
| 491 | * then link_info has been deleted and we should return |
| 492 | * immediately. */ |
| 493 | if (gbproxy_flush_stored_messages(peer, now, link_info) < 0) |
| 494 | return 0; |
| 495 | |
| 496 | gbproxy_reset_imsi_acquisition(link_info); |
| 497 | |
| 498 | /* This message is most probably the response to the ident |
| 499 | * request sent by gbproxy_acquire_imsi(). Don't forward it to |
| 500 | * the SGSN. */ |
| 501 | return !is_ident_resp; |
| 502 | } |
| 503 | |
| 504 | /* The message cannot be processed since the IMSI is still missing */ |
| 505 | |
| 506 | /* If queue is getting too large, drop oldest msgb before adding new one */ |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 507 | if (cfg->stored_msgs_max_len > 0) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 508 | int exceeded_max_len = link_info->stored_msgs_len |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 509 | + 1 - cfg->stored_msgs_max_len; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 510 | |
| 511 | for (; exceeded_max_len > 0; exceeded_max_len--) { |
| 512 | struct msgb *msgb_drop; |
| 513 | msgb_drop = msgb_dequeue_count(&link_info->stored_msgs, |
| 514 | &link_info->stored_msgs_len); |
| 515 | LOGP(DLLC, LOGL_INFO, |
| 516 | "NSEI=%d(BSS) Dropping stored msgb from list " |
| 517 | "(!acq imsi, length %d, max_len exceeded)\n", |
| 518 | msgb_nsei(msgb_drop), link_info->stored_msgs_len); |
| 519 | |
| 520 | msgb_free(msgb_drop); |
| 521 | } |
| 522 | } |
| 523 | |
| 524 | /* Enqueue unpatched messages */ |
| 525 | LOGP(DLLC, LOGL_INFO, |
| 526 | "NSEI=%d(BSS) IMSI acquisition in progress, " |
| 527 | "storing message (%s)\n", |
| 528 | msgb_nsei(msg), |
| 529 | parse_ctx->llc_msg_name ? parse_ctx->llc_msg_name : "BSSGP"); |
| 530 | |
| 531 | stored_msg = bssgp_msgb_copy(msg, "process_bssgp_ul"); |
| 532 | msgb_enqueue_count(&link_info->stored_msgs, stored_msg, |
| 533 | &link_info->stored_msgs_len); |
| 534 | |
| 535 | if (!link_info->imsi_acq_pending) { |
| 536 | LOGP(DLLC, LOGL_INFO, |
| 537 | "NSEI=%d(BSS) IMSI is required but not available, " |
| 538 | "initiating identification procedure (%s)\n", |
| 539 | msgb_nsei(msg), |
| 540 | parse_ctx->llc_msg_name ? parse_ctx->llc_msg_name : "BSSGP"); |
| 541 | |
| 542 | gbproxy_acquire_imsi(peer, link_info, msgb_bvci(msg)); |
| 543 | |
| 544 | /* There is no explicit retransmission handling, the |
| 545 | * implementation relies on the MS doing proper retransmissions |
| 546 | * of the triggering message instead */ |
| 547 | |
| 548 | link_info->imsi_acq_pending = true; |
| 549 | } |
| 550 | |
| 551 | return 0; |
| 552 | } |
| 553 | |
| 554 | struct gbproxy_peer *gbproxy_find_peer(struct gbproxy_config *cfg, |
| 555 | struct msgb *msg, |
| 556 | struct gprs_gb_parse_context *parse_ctx) |
| 557 | { |
| 558 | struct gbproxy_peer *peer = NULL; |
| 559 | |
| 560 | if (msgb_bvci(msg) >= 2) |
| 561 | peer = gbproxy_peer_by_bvci(cfg, msgb_bvci(msg)); |
| 562 | |
| 563 | if (!peer && !parse_ctx->to_bss) |
| 564 | peer = gbproxy_peer_by_nsei(cfg, msgb_nsei(msg)); |
| 565 | |
| 566 | if (!peer) |
| 567 | peer = gbproxy_peer_by_bssgp_tlv(cfg, &parse_ctx->bssgp_tp); |
| 568 | |
| 569 | if (!peer) { |
| 570 | LOGP(DLLC, LOGL_INFO, |
| 571 | "NSEI=%d(%s) patching: didn't find peer for message, " |
| 572 | "PDU %d\n", |
| 573 | msgb_nsei(msg), parse_ctx->to_bss ? "BSS" : "SGSN", |
| 574 | parse_ctx->pdu_type); |
| 575 | /* Increment counter */ |
| 576 | rate_ctr_inc(&cfg->ctrg->ctr[GBPROX_GLOB_CTR_PATCH_PEER_ERR]); |
| 577 | } |
| 578 | return peer; |
| 579 | } |
| 580 | |
| 581 | /* patch BSSGP message */ |
| 582 | static int gbprox_process_bssgp_ul(struct gbproxy_config *cfg, |
| 583 | struct msgb *msg, |
| 584 | struct gbproxy_peer *peer) |
| 585 | { |
| 586 | struct gprs_gb_parse_context parse_ctx = {0}; |
| 587 | int rc; |
| 588 | int len_change = 0; |
| 589 | time_t now; |
| 590 | struct timespec ts = {0,}; |
| 591 | struct gbproxy_link_info *link_info = NULL; |
| 592 | uint32_t sgsn_nsei = cfg->nsip_sgsn_nsei; |
| 593 | |
| 594 | if (!cfg->core_plmn.mcc && !cfg->core_plmn.mnc && !cfg->core_apn && |
| 595 | !cfg->acquire_imsi && !cfg->patch_ptmsi && !cfg->route_to_sgsn2) |
| 596 | return 1; |
| 597 | |
| 598 | parse_ctx.to_bss = 0; |
| 599 | parse_ctx.peer_nsei = msgb_nsei(msg); |
| 600 | |
| 601 | /* Parse BSSGP/LLC */ |
| 602 | rc = gprs_gb_parse_bssgp(msgb_bssgph(msg), msgb_bssgp_len(msg), |
| 603 | &parse_ctx); |
| 604 | |
| 605 | if (!rc && !parse_ctx.need_decryption) { |
| 606 | LOGP(DGPRS, LOGL_ERROR, |
| 607 | "NSEI=%u(BSS) patching: failed to parse invalid %s message\n", |
| 608 | msgb_nsei(msg), gprs_gb_message_name(&parse_ctx, "NS_UNITDATA")); |
| 609 | gprs_gb_log_parse_context(LOGL_NOTICE, &parse_ctx, "NS_UNITDATA"); |
| 610 | LOGP(DGPRS, LOGL_NOTICE, |
| 611 | "NSEI=%u(BSS) invalid message was: %s\n", |
| 612 | msgb_nsei(msg), msgb_hexdump(msg)); |
| 613 | return 0; |
| 614 | } |
| 615 | |
| 616 | /* Get peer */ |
| 617 | if (!peer) |
| 618 | peer = gbproxy_find_peer(cfg, msg, &parse_ctx); |
| 619 | |
| 620 | if (!peer) |
| 621 | return 0; |
| 622 | |
| 623 | |
| 624 | osmo_clock_gettime(CLOCK_MONOTONIC, &ts); |
| 625 | now = ts.tv_sec; |
| 626 | |
| 627 | gbprox_update_current_raid(parse_ctx.bssgp_raid_enc, peer, |
| 628 | parse_ctx.llc_msg_name); |
| 629 | |
| 630 | gprs_gb_log_parse_context(LOGL_DEBUG, &parse_ctx, "NS_UNITDATA"); |
| 631 | |
| 632 | link_info = gbproxy_update_link_state_ul(peer, now, &parse_ctx); |
| 633 | |
| 634 | if (parse_ctx.g48_hdr) { |
| 635 | switch (parse_ctx.g48_hdr->msg_type) { |
| 636 | case GSM48_MT_GMM_ATTACH_REQ: |
| 637 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_ATTACH_REQS]); |
| 638 | break; |
| 639 | case GSM48_MT_GMM_DETACH_REQ: |
| 640 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_DETACH_REQS]); |
| 641 | break; |
| 642 | case GSM48_MT_GMM_ATTACH_COMPL: |
| 643 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_ATTACH_COMPLS]); |
| 644 | break; |
| 645 | case GSM48_MT_GMM_RA_UPD_REQ: |
| 646 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_RA_UPD_REQS]); |
| 647 | break; |
| 648 | case GSM48_MT_GMM_RA_UPD_COMPL: |
| 649 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_RA_UPD_COMPLS]); |
| 650 | break; |
| 651 | case GSM48_MT_GMM_STATUS: |
| 652 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_GMM_STATUS_BSS]); |
| 653 | break; |
| 654 | case GSM48_MT_GSM_ACT_PDP_REQ: |
| 655 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_PDP_ACT_REQS]); |
| 656 | break; |
| 657 | case GSM48_MT_GSM_DEACT_PDP_REQ: |
| 658 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_PDP_DEACT_REQS]); |
| 659 | break; |
| 660 | |
| 661 | default: |
| 662 | break; |
| 663 | } |
| 664 | } |
| 665 | |
| 666 | if (link_info && cfg->route_to_sgsn2) { |
| 667 | if (cfg->acquire_imsi && link_info->imsi_len == 0) |
| 668 | sgsn_nsei = 0xffff; |
| 669 | else if (gbproxy_imsi_matches(cfg, GBPROX_MATCH_ROUTING, |
| 670 | link_info)) |
| 671 | sgsn_nsei = cfg->nsip_sgsn2_nsei; |
| 672 | } |
| 673 | |
| 674 | if (link_info) |
| 675 | link_info->sgsn_nsei = sgsn_nsei; |
| 676 | |
| 677 | /* Handle IMSI acquisition */ |
| 678 | if (cfg->acquire_imsi) { |
| 679 | rc = gbproxy_imsi_acquisition(peer, msg, now, link_info, |
| 680 | &parse_ctx); |
| 681 | if (rc <= 0) |
| 682 | return rc; |
| 683 | } |
| 684 | |
| 685 | gbproxy_patch_bssgp(msg, msgb_bssgph(msg), msgb_bssgp_len(msg), |
| 686 | peer, link_info, &len_change, &parse_ctx); |
| 687 | |
| 688 | gbproxy_update_link_state_after(peer, link_info, now, &parse_ctx); |
| 689 | |
| 690 | if (sgsn_nsei != cfg->nsip_sgsn_nsei) { |
| 691 | /* Send message directly to the selected SGSN */ |
| 692 | rc = gbprox_relay2sgsn(cfg, msg, msgb_bvci(msg), sgsn_nsei); |
| 693 | /* Don't let the calling code handle the transmission */ |
| 694 | return 0; |
| 695 | } |
| 696 | |
| 697 | return 1; |
| 698 | } |
| 699 | |
| 700 | /* patch BSSGP message to use core_plmn.mcc/mnc on the SGSN side */ |
| 701 | static void gbprox_process_bssgp_dl(struct gbproxy_config *cfg, |
| 702 | struct msgb *msg, |
| 703 | struct gbproxy_peer *peer) |
| 704 | { |
| 705 | struct gprs_gb_parse_context parse_ctx = {0}; |
| 706 | int rc; |
| 707 | int len_change = 0; |
| 708 | time_t now; |
| 709 | struct timespec ts = {0,}; |
| 710 | struct gbproxy_link_info *link_info = NULL; |
| 711 | |
| 712 | if (!cfg->core_plmn.mcc && !cfg->core_plmn.mnc && !cfg->core_apn && |
| 713 | !cfg->acquire_imsi && !cfg->patch_ptmsi && !cfg->route_to_sgsn2) |
| 714 | return; |
| 715 | |
| 716 | parse_ctx.to_bss = 1; |
| 717 | parse_ctx.peer_nsei = msgb_nsei(msg); |
| 718 | |
| 719 | rc = gprs_gb_parse_bssgp(msgb_bssgph(msg), msgb_bssgp_len(msg), |
| 720 | &parse_ctx); |
| 721 | |
| 722 | if (!rc && !parse_ctx.need_decryption) { |
| 723 | LOGP(DGPRS, LOGL_ERROR, |
| 724 | "NSEI=%u(SGSN) patching: failed to parse invalid %s message\n", |
| 725 | msgb_nsei(msg), gprs_gb_message_name(&parse_ctx, "NS_UNITDATA")); |
| 726 | gprs_gb_log_parse_context(LOGL_NOTICE, &parse_ctx, "NS_UNITDATA"); |
| 727 | LOGP(DGPRS, LOGL_NOTICE, |
| 728 | "NSEI=%u(SGSN) invalid message was: %s\n", |
| 729 | msgb_nsei(msg), msgb_hexdump(msg)); |
| 730 | return; |
| 731 | } |
| 732 | |
| 733 | /* Get peer */ |
| 734 | if (!peer) |
| 735 | peer = gbproxy_find_peer(cfg, msg, &parse_ctx); |
| 736 | |
| 737 | if (!peer) |
| 738 | return; |
| 739 | |
| 740 | osmo_clock_gettime(CLOCK_MONOTONIC, &ts); |
| 741 | now = ts.tv_sec; |
| 742 | |
| 743 | if (parse_ctx.g48_hdr) { |
| 744 | switch (parse_ctx.g48_hdr->msg_type) { |
| 745 | case GSM48_MT_GMM_ATTACH_ACK: |
| 746 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_ATTACH_ACKS]); |
| 747 | break; |
| 748 | case GSM48_MT_GMM_ATTACH_REJ: |
| 749 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_ATTACH_REJS]); |
| 750 | break; |
| 751 | case GSM48_MT_GMM_DETACH_ACK: |
| 752 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_DETACH_ACKS]); |
| 753 | break; |
| 754 | case GSM48_MT_GMM_RA_UPD_ACK: |
| 755 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_RA_UPD_ACKS]); |
| 756 | break; |
| 757 | case GSM48_MT_GMM_RA_UPD_REJ: |
| 758 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_RA_UPD_REJS]); |
| 759 | break; |
| 760 | case GSM48_MT_GMM_STATUS: |
| 761 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_GMM_STATUS_SGSN]); |
| 762 | break; |
| 763 | case GSM48_MT_GSM_ACT_PDP_ACK: |
| 764 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_PDP_ACT_ACKS]); |
| 765 | break; |
| 766 | case GSM48_MT_GSM_ACT_PDP_REJ: |
| 767 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_PDP_ACT_REJS]); |
| 768 | break; |
| 769 | case GSM48_MT_GSM_DEACT_PDP_ACK: |
| 770 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_PDP_DEACT_ACKS]); |
| 771 | break; |
| 772 | |
| 773 | default: |
| 774 | break; |
| 775 | } |
| 776 | } |
| 777 | |
| 778 | gprs_gb_log_parse_context(LOGL_DEBUG, &parse_ctx, "NS_UNITDATA"); |
| 779 | |
| 780 | link_info = gbproxy_update_link_state_dl(peer, now, &parse_ctx); |
| 781 | |
| 782 | gbproxy_patch_bssgp(msg, msgb_bssgph(msg), msgb_bssgp_len(msg), |
| 783 | peer, link_info, &len_change, &parse_ctx); |
| 784 | |
| 785 | gbproxy_update_link_state_after(peer, link_info, now, &parse_ctx); |
| 786 | |
| 787 | return; |
| 788 | } |
| 789 | |
| 790 | /* feed a message down the NS-VC associated with the specified peer */ |
| 791 | static int gbprox_relay2sgsn(struct gbproxy_config *cfg, struct msgb *old_msg, |
| 792 | uint16_t ns_bvci, uint16_t sgsn_nsei) |
| 793 | { |
| 794 | /* create a copy of the message so the old one can |
| 795 | * be free()d safely when we return from gbprox_rcvmsg() */ |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 796 | struct gprs_ns2_inst *nsi = cfg->nsi; |
| 797 | struct osmo_gprs_ns2_prim nsp = {}; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 798 | struct msgb *msg = bssgp_msgb_copy(old_msg, "msgb_relay2sgsn"); |
| 799 | int rc; |
| 800 | |
| 801 | DEBUGP(DGPRS, "NSEI=%u proxying BTS->SGSN (NS_BVCI=%u, NSEI=%u)\n", |
| 802 | msgb_nsei(msg), ns_bvci, sgsn_nsei); |
| 803 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 804 | nsp.bvci = ns_bvci; |
| 805 | nsp.nsei = sgsn_nsei; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 806 | |
| 807 | strip_ns_hdr(msg); |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 808 | osmo_prim_init(&nsp.oph, SAP_NS, PRIM_NS_UNIT_DATA, |
| 809 | PRIM_OP_REQUEST, msg); |
| 810 | rc = gprs_ns2_recv_prim(nsi, &nsp.oph); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 811 | if (rc < 0) |
| 812 | rate_ctr_inc(&cfg->ctrg->ctr[GBPROX_GLOB_CTR_TX_ERR_SGSN]); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 813 | return rc; |
| 814 | } |
| 815 | |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 816 | /* feed a message down the NSE */ |
| 817 | static int gbprox_relay2nse(struct msgb *old_msg, struct gbproxy_nse *nse, |
Daniel Willmann | 35f7d33 | 2020-11-03 21:11:45 +0100 | [diff] [blame] | 818 | uint16_t ns_bvci) |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 819 | { |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 820 | OSMO_ASSERT(nse); |
| 821 | OSMO_ASSERT(nse->cfg); |
| 822 | |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 823 | /* create a copy of the message so the old one can |
| 824 | * be free()d safely when we return from gbprox_rcvmsg() */ |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 825 | struct gprs_ns2_inst *nsi = nse->cfg->nsi; |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 826 | struct osmo_gprs_ns2_prim nsp = {}; |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 827 | struct msgb *msg = bssgp_msgb_copy(old_msg, "msgb_relay2nse"); |
Harald Welte | fe05958 | 2020-11-18 12:01:46 +0100 | [diff] [blame] | 828 | uint32_t tlli; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 829 | int rc; |
| 830 | |
| 831 | DEBUGP(DGPRS, "NSEI=%u proxying SGSN->BSS (NS_BVCI=%u, NSEI=%u)\n", |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 832 | msgb_nsei(msg), ns_bvci, nse->nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 833 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 834 | nsp.bvci = ns_bvci; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 835 | nsp.nsei = nse->nsei; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 836 | |
| 837 | /* Strip the old NS header, it will be replaced with a new one */ |
| 838 | strip_ns_hdr(msg); |
| 839 | |
Harald Welte | fe05958 | 2020-11-18 12:01:46 +0100 | [diff] [blame] | 840 | /* TS 48.018 Section 5.4.2: The link selector parameter is |
| 841 | * defined in 3GPP TS 48.016. At one side of the Gb interface, |
| 842 | * all BSSGP UNITDATA PDUs related to an MS shall be passed with |
| 843 | * the same LSP, e.g. the LSP contains the MS's TLLI, to the |
| 844 | * underlying network service. */ |
| 845 | if (gprs_gb_parse_tlli(msgb_data(msg), msgb_length(msg), &tlli) == 1) |
| 846 | nsp.u.unitdata.link_selector = tlli; |
| 847 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 848 | osmo_prim_init(&nsp.oph, SAP_NS, PRIM_NS_UNIT_DATA, |
| 849 | PRIM_OP_REQUEST, msg); |
| 850 | rc = gprs_ns2_recv_prim(nsi, &nsp.oph); |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 851 | /* FIXME: We need a counter group for gbproxy_nse */ |
| 852 | //if (rc < 0) |
| 853 | // rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_TX_ERR]); |
| 854 | |
| 855 | return rc; |
| 856 | } |
| 857 | |
| 858 | /* feed a message down the NS-VC associated with the specified peer */ |
| 859 | static int gbprox_relay2peer(struct msgb *old_msg, struct gbproxy_peer *peer, |
| 860 | uint16_t ns_bvci) |
| 861 | { |
| 862 | int rc; |
| 863 | struct gbproxy_nse *nse = peer->nse; |
| 864 | OSMO_ASSERT(nse); |
| 865 | |
| 866 | rc = gbprox_relay2nse(old_msg, nse, ns_bvci); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 867 | if (rc < 0) |
| 868 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_TX_ERR]); |
| 869 | |
| 870 | return rc; |
| 871 | } |
| 872 | |
| 873 | static int block_unblock_peer(struct gbproxy_config *cfg, uint16_t ptp_bvci, uint8_t pdu_type) |
| 874 | { |
| 875 | struct gbproxy_peer *peer; |
| 876 | |
| 877 | peer = gbproxy_peer_by_bvci(cfg, ptp_bvci); |
| 878 | if (!peer) { |
| 879 | LOGP(DGPRS, LOGL_ERROR, "BVCI=%u: Cannot find BSS\n", |
| 880 | ptp_bvci); |
| 881 | rate_ctr_inc(&cfg->ctrg->ctr[GBPROX_GLOB_CTR_INV_BVCI]); |
| 882 | return -ENOENT; |
| 883 | } |
| 884 | |
| 885 | switch (pdu_type) { |
| 886 | case BSSGP_PDUT_BVC_BLOCK_ACK: |
| 887 | peer->blocked = true; |
| 888 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_BLOCKED]); |
| 889 | break; |
| 890 | case BSSGP_PDUT_BVC_UNBLOCK_ACK: |
| 891 | peer->blocked = false; |
| 892 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_UNBLOCKED]); |
| 893 | break; |
| 894 | default: |
| 895 | break; |
| 896 | } |
| 897 | return 0; |
| 898 | } |
| 899 | |
| 900 | /* Send a message to a peer identified by ptp_bvci but using ns_bvci |
| 901 | * in the NS hdr */ |
| 902 | static int gbprox_relay2bvci(struct gbproxy_config *cfg, struct msgb *msg, uint16_t ptp_bvci, |
| 903 | uint16_t ns_bvci) |
| 904 | { |
| 905 | struct gbproxy_peer *peer; |
| 906 | |
| 907 | peer = gbproxy_peer_by_bvci(cfg, ptp_bvci); |
| 908 | if (!peer) { |
| 909 | LOGP(DGPRS, LOGL_ERROR, "BVCI=%u: Cannot find BSS\n", |
| 910 | ptp_bvci); |
| 911 | rate_ctr_inc(&cfg->ctrg->ctr[GBPROX_GLOB_CTR_INV_BVCI]); |
| 912 | return -ENOENT; |
| 913 | } |
| 914 | |
| 915 | return gbprox_relay2peer(msg, peer, ns_bvci); |
| 916 | } |
| 917 | |
| 918 | int bssgp_prim_cb(struct osmo_prim_hdr *oph, void *ctx) |
| 919 | { |
| 920 | return 0; |
| 921 | } |
| 922 | |
| 923 | /* Receive an incoming PTP message from a BSS-side NS-VC */ |
| 924 | static int gbprox_rx_ptp_from_bss(struct gbproxy_config *cfg, |
| 925 | struct msgb *msg, uint16_t nsei, |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 926 | uint16_t ns_bvci) |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 927 | { |
| 928 | struct gbproxy_peer *peer; |
| 929 | struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg); |
| 930 | uint8_t pdu_type = bgph->pdu_type; |
| 931 | int rc; |
| 932 | |
| 933 | peer = gbproxy_peer_by_bvci(cfg, ns_bvci); |
| 934 | if (!peer) { |
| 935 | LOGP(DGPRS, LOGL_NOTICE, "Didn't find peer for " |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 936 | "BVCI=%u for PTP message from NSEI=%u (BSS), " |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 937 | "discarding message\n", |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 938 | ns_bvci, nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 939 | return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, |
| 940 | &ns_bvci, msg); |
| 941 | } |
| 942 | |
| 943 | check_peer_nsei(peer, nsei); |
| 944 | |
| 945 | rc = gbprox_process_bssgp_ul(cfg, msg, peer); |
| 946 | if (!rc) |
| 947 | return 0; |
| 948 | |
| 949 | switch (pdu_type) { |
| 950 | case BSSGP_PDUT_FLOW_CONTROL_BVC: |
| 951 | if (!cfg->route_to_sgsn2) |
| 952 | break; |
| 953 | |
| 954 | /* Send a copy to the secondary SGSN */ |
| 955 | gbprox_relay2sgsn(cfg, msg, ns_bvci, cfg->nsip_sgsn2_nsei); |
| 956 | break; |
| 957 | default: |
| 958 | break; |
| 959 | } |
| 960 | |
| 961 | |
| 962 | return gbprox_relay2sgsn(cfg, msg, ns_bvci, cfg->nsip_sgsn_nsei); |
| 963 | } |
| 964 | |
| 965 | /* Receive an incoming PTP message from a SGSN-side NS-VC */ |
| 966 | static int gbprox_rx_ptp_from_sgsn(struct gbproxy_config *cfg, |
| 967 | struct msgb *msg, uint16_t nsei, |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 968 | uint16_t ns_bvci) |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 969 | { |
| 970 | struct gbproxy_peer *peer; |
| 971 | struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg); |
| 972 | uint8_t pdu_type = bgph->pdu_type; |
| 973 | |
| 974 | peer = gbproxy_peer_by_bvci(cfg, ns_bvci); |
| 975 | |
| 976 | /* Send status messages before patching */ |
| 977 | |
| 978 | if (!peer) { |
| 979 | LOGP(DGPRS, LOGL_INFO, "Didn't find peer for " |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 980 | "BVCI=%u for message from NSEI=%u (SGSN)\n", |
| 981 | ns_bvci, nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 982 | rate_ctr_inc(&cfg->ctrg-> |
| 983 | ctr[GBPROX_GLOB_CTR_INV_BVCI]); |
| 984 | return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, |
| 985 | &ns_bvci, msg); |
| 986 | } |
| 987 | |
| 988 | if (peer->blocked) { |
| 989 | LOGP(DGPRS, LOGL_NOTICE, "Dropping PDU for " |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 990 | "blocked BVCI=%u via NSEI=%u\n", |
| 991 | ns_bvci, nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 992 | rate_ctr_inc(&peer->ctrg->ctr[GBPROX_PEER_CTR_DROPPED]); |
| 993 | return bssgp_tx_status(BSSGP_CAUSE_BVCI_BLOCKED, &ns_bvci, msg); |
| 994 | } |
| 995 | |
| 996 | switch (pdu_type) { |
| 997 | case BSSGP_PDUT_FLOW_CONTROL_BVC_ACK: |
| 998 | case BSSGP_PDUT_BVC_BLOCK_ACK: |
| 999 | case BSSGP_PDUT_BVC_UNBLOCK_ACK: |
| 1000 | if (cfg->route_to_sgsn2 && nsei == cfg->nsip_sgsn2_nsei) |
| 1001 | /* Hide ACKs from the secondary SGSN, the primary SGSN |
| 1002 | * is responsible to send them. */ |
| 1003 | return 0; |
| 1004 | break; |
| 1005 | default: |
| 1006 | break; |
| 1007 | } |
| 1008 | |
| 1009 | /* Optionally patch the message */ |
| 1010 | gbprox_process_bssgp_dl(cfg, msg, peer); |
| 1011 | |
| 1012 | return gbprox_relay2peer(msg, peer, ns_bvci); |
| 1013 | } |
| 1014 | |
| 1015 | /* Receive an incoming signalling message from a BSS-side NS-VC */ |
| 1016 | static int gbprox_rx_sig_from_bss(struct gbproxy_config *cfg, |
| 1017 | struct msgb *msg, uint16_t nsei, |
| 1018 | uint16_t ns_bvci) |
| 1019 | { |
| 1020 | struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg); |
| 1021 | struct tlv_parsed tp; |
| 1022 | uint8_t pdu_type = bgph->pdu_type; |
| 1023 | int data_len = msgb_bssgp_len(msg) - sizeof(*bgph); |
| 1024 | struct gbproxy_peer *from_peer = NULL; |
| 1025 | struct gprs_ra_id raid; |
| 1026 | int copy_to_sgsn2 = 0; |
| 1027 | int rc; |
| 1028 | |
| 1029 | if (ns_bvci != 0 && ns_bvci != 1) { |
| 1030 | LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u BVCI=%u is not signalling\n", |
| 1031 | nsei, ns_bvci); |
| 1032 | return -EINVAL; |
| 1033 | } |
| 1034 | |
| 1035 | /* we actually should never see those two for BVCI == 0, but double-check |
| 1036 | * just to make sure */ |
| 1037 | if (pdu_type == BSSGP_PDUT_UL_UNITDATA || |
| 1038 | pdu_type == BSSGP_PDUT_DL_UNITDATA) { |
| 1039 | LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u UNITDATA not allowed in " |
| 1040 | "signalling\n", nsei); |
| 1041 | return -EINVAL; |
| 1042 | } |
| 1043 | |
| 1044 | bssgp_tlv_parse(&tp, bgph->data, data_len); |
| 1045 | |
| 1046 | switch (pdu_type) { |
| 1047 | case BSSGP_PDUT_SUSPEND: |
| 1048 | case BSSGP_PDUT_RESUME: |
| 1049 | /* We implement RAI snooping during SUSPEND/RESUME, since it |
| 1050 | * establishes a relationsip between BVCI/peer and the routeing |
| 1051 | * area identification. The snooped information is then used |
| 1052 | * for routing the {SUSPEND,RESUME}_[N]ACK back to the correct |
| 1053 | * BSSGP */ |
| 1054 | if (!TLVP_PRESENT(&tp, BSSGP_IE_ROUTEING_AREA)) |
| 1055 | goto err_mand_ie; |
| 1056 | from_peer = gbproxy_peer_by_nsei(cfg, nsei); |
| 1057 | if (!from_peer) |
| 1058 | goto err_no_peer; |
| 1059 | memcpy(from_peer->ra, TLVP_VAL(&tp, BSSGP_IE_ROUTEING_AREA), |
| 1060 | sizeof(from_peer->ra)); |
| 1061 | gsm48_parse_ra(&raid, from_peer->ra); |
| 1062 | LOGP(DGPRS, LOGL_INFO, "NSEI=%u BSSGP SUSPEND/RESUME " |
| 1063 | "RAI snooping: RAI %s behind BVCI=%u\n", |
| 1064 | nsei, osmo_rai_name(&raid), from_peer->bvci); |
| 1065 | /* FIXME: This only supports one BSS per RA */ |
| 1066 | break; |
| 1067 | case BSSGP_PDUT_BVC_RESET: |
| 1068 | /* If we receive a BVC reset on the signalling endpoint, we |
| 1069 | * don't want the SGSN to reset, as the signalling endpoint |
| 1070 | * is common for all point-to-point BVCs (and thus all BTS) */ |
| 1071 | if (TLVP_PRESENT(&tp, BSSGP_IE_BVCI)) { |
| 1072 | uint16_t bvci = ntohs(tlvp_val16_unal(&tp, BSSGP_IE_BVCI)); |
| 1073 | LOGP(DGPRS, LOGL_INFO, "NSEI=%u Rx BVC RESET (BVCI=%u)\n", |
| 1074 | nsei, bvci); |
| 1075 | if (bvci == 0) { |
Daniel Willmann | af7398a | 2020-11-30 14:28:52 +0100 | [diff] [blame] | 1076 | struct gbproxy_nse *nse; |
| 1077 | /* Ensure the NSE peer is there and clear all PtP BVCs */ |
| 1078 | nse = gbproxy_nse_by_nsei_or_new(cfg, nsei); |
| 1079 | if (!nse) |
| 1080 | LOGP(DGPRS, LOGL_ERROR, "Could not allocate NSE for NSEI=%u\n", nsei); |
| 1081 | |
| 1082 | gbproxy_cleanup_peers(cfg, nsei, 0); |
| 1083 | |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1084 | /* FIXME: only do this if SGSN is alive! */ |
| 1085 | LOGP(DGPRS, LOGL_INFO, "NSEI=%u Tx fake " |
| 1086 | "BVC RESET ACK of BVCI=0\n", nsei); |
| 1087 | return bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_RESET_ACK, |
| 1088 | nsei, 0, ns_bvci); |
| 1089 | } |
| 1090 | from_peer = gbproxy_peer_by_bvci(cfg, bvci); |
| 1091 | if (!from_peer) { |
Daniel Willmann | af7398a | 2020-11-30 14:28:52 +0100 | [diff] [blame] | 1092 | struct gbproxy_nse *nse = gbproxy_nse_by_nsei(cfg, nsei); |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1093 | if (!nse) { |
Daniel Willmann | af7398a | 2020-11-30 14:28:52 +0100 | [diff] [blame] | 1094 | LOGP(DGPRS, LOGL_NOTICE, "Got PtP BVC reset before signalling reset for " |
| 1095 | "BVCI=%u NSEI=%u\n", bvci, nsei); |
| 1096 | return bssgp_tx_status(BSSGP_CAUSE_PDU_INCOMP_STATE, NULL, msg); |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1097 | } |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1098 | /* if a PTP-BVC is reset, and we don't know that |
| 1099 | * PTP-BVCI yet, we should allocate a new peer */ |
| 1100 | LOGP(DGPRS, LOGL_INFO, "Allocationg new peer for BVCI=%u via NSEI=%u\n", bvci, nsei); |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1101 | from_peer = gbproxy_peer_alloc(nse, bvci); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1102 | OSMO_ASSERT(from_peer); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1103 | } |
| 1104 | |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1105 | /* Could have moved to a different NSE */ |
| 1106 | if (!check_peer_nsei(from_peer, nsei)) { |
| 1107 | struct gbproxy_nse *nse_old = from_peer->nse; |
Daniel Willmann | af7398a | 2020-11-30 14:28:52 +0100 | [diff] [blame] | 1108 | struct gbproxy_nse *nse_new = gbproxy_nse_by_nsei(cfg, nsei); |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1109 | if (!nse_new) { |
Daniel Willmann | af7398a | 2020-11-30 14:28:52 +0100 | [diff] [blame] | 1110 | LOGP(DGPRS, LOGL_NOTICE, "Got PtP BVC reset before signalling reset for " |
| 1111 | "BVCI=%u NSEI=%u\n", bvci, nsei); |
| 1112 | return bssgp_tx_status(BSSGP_CAUSE_PDU_INCOMP_STATE, NULL, msg); |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1113 | } |
| 1114 | LOGP(DGPRS, LOGL_NOTICE, "Peer for BVCI=%u moved from NSEI=%u to NSEI=%u\n", bvci, nse_old->nsei, nsei); |
| 1115 | |
| 1116 | /* Move peer to different NSE */ |
Daniel Willmann | 559edac | 2020-11-30 17:14:24 +0100 | [diff] [blame] | 1117 | gbproxy_peer_move(from_peer, nse_new); |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1118 | } |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1119 | |
| 1120 | if (TLVP_PRESENT(&tp, BSSGP_IE_CELL_ID)) { |
| 1121 | struct gprs_ra_id raid; |
| 1122 | /* We have a Cell Identifier present in this |
| 1123 | * PDU, this means we can extend our local |
| 1124 | * state information about this particular cell |
| 1125 | * */ |
| 1126 | memcpy(from_peer->ra, |
| 1127 | TLVP_VAL(&tp, BSSGP_IE_CELL_ID), |
| 1128 | sizeof(from_peer->ra)); |
| 1129 | gsm48_parse_ra(&raid, from_peer->ra); |
| 1130 | LOGP(DGPRS, LOGL_INFO, "NSEI=%u/BVCI=%u Cell ID %s\n", |
| 1131 | nsei, bvci, osmo_rai_name(&raid)); |
| 1132 | } |
| 1133 | if (cfg->route_to_sgsn2) |
| 1134 | copy_to_sgsn2 = 1; |
| 1135 | } |
| 1136 | break; |
| 1137 | } |
| 1138 | |
| 1139 | /* Normally, we can simply pass on all signalling messages from BSS to |
| 1140 | * SGSN */ |
| 1141 | rc = gbprox_process_bssgp_ul(cfg, msg, from_peer); |
| 1142 | if (!rc) |
| 1143 | return 0; |
| 1144 | |
| 1145 | if (copy_to_sgsn2) |
| 1146 | gbprox_relay2sgsn(cfg, msg, ns_bvci, cfg->nsip_sgsn2_nsei); |
| 1147 | |
| 1148 | return gbprox_relay2sgsn(cfg, msg, ns_bvci, cfg->nsip_sgsn_nsei); |
| 1149 | err_no_peer: |
| 1150 | LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(BSS) cannot find peer based on NSEI\n", |
| 1151 | nsei); |
| 1152 | rate_ctr_inc(&cfg->ctrg->ctr[GBPROX_GLOB_CTR_INV_NSEI]); |
| 1153 | return bssgp_tx_status(BSSGP_CAUSE_INV_MAND_INF, NULL, msg); |
| 1154 | err_mand_ie: |
| 1155 | LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(BSS) missing mandatory RA IE\n", |
| 1156 | nsei); |
| 1157 | rate_ctr_inc(&cfg->ctrg->ctr[GBPROX_GLOB_CTR_PROTO_ERR_BSS]); |
| 1158 | return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg); |
| 1159 | } |
| 1160 | |
| 1161 | /* Receive paging request from SGSN, we need to relay to proper BSS */ |
| 1162 | static int gbprox_rx_paging(struct gbproxy_config *cfg, struct msgb *msg, struct tlv_parsed *tp, |
| 1163 | uint32_t nsei, uint16_t ns_bvci) |
| 1164 | { |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1165 | struct gbproxy_nse *nse; |
Harald Welte | 3d1bd4d | 2020-11-23 15:14:20 +0100 | [diff] [blame] | 1166 | struct gbproxy_peer *peer; |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 1167 | unsigned int n_nses = 0; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1168 | int errctr = GBPROX_GLOB_CTR_PROTO_ERR_SGSN; |
| 1169 | |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1170 | /* FIXME: Handle paging logic to only page each matching NSE */ |
| 1171 | |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1172 | LOGP(DGPRS, LOGL_INFO, "NSEI=%u(SGSN) BSSGP PAGING ", |
| 1173 | nsei); |
| 1174 | if (TLVP_PRESENT(tp, BSSGP_IE_BVCI)) { |
| 1175 | uint16_t bvci = ntohs(tlvp_val16_unal(tp, BSSGP_IE_BVCI)); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1176 | errctr = GBPROX_GLOB_CTR_OTHER_ERR; |
Harald Welte | 3d1bd4d | 2020-11-23 15:14:20 +0100 | [diff] [blame] | 1177 | peer = gbproxy_peer_by_bvci(cfg, bvci); |
| 1178 | LOGPC(DGPRS, LOGL_INFO, "routing by BVCI to peer BVCI=%u\n", bvci); |
| 1179 | if (!peer) { |
| 1180 | LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u(SGSN) BSSGP PAGING: " |
| 1181 | "unable to route: BVCI=%u unknown\n", nsei, bvci); |
| 1182 | rate_ctr_inc(&cfg->ctrg->ctr[errctr]); |
| 1183 | return -EINVAL; |
| 1184 | } |
| 1185 | return gbprox_relay2peer(msg, peer, ns_bvci); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1186 | } else if (TLVP_PRESENT(tp, BSSGP_IE_ROUTEING_AREA)) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1187 | errctr = GBPROX_GLOB_CTR_INV_RAI; |
Harald Welte | 3d1bd4d | 2020-11-23 15:14:20 +0100 | [diff] [blame] | 1188 | /* iterate over all peers and dispatch the paging to each matching one */ |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1189 | llist_for_each_entry(nse, &cfg->nse_peers, list) { |
| 1190 | llist_for_each_entry(peer, &nse->bts_peers, list) { |
| 1191 | if (!memcmp(peer->ra, TLVP_VAL(tp, BSSGP_IE_ROUTEING_AREA), 6)) { |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 1192 | LOGPC(DGPRS, LOGL_INFO, "routing by RAI to peer NSEI=%u\n", peer->bvci); |
| 1193 | gbprox_relay2nse(msg, nse, ns_bvci); |
| 1194 | n_nses++; |
| 1195 | /* Only send it once to each NSE */ |
| 1196 | break; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1197 | } |
Harald Welte | 3d1bd4d | 2020-11-23 15:14:20 +0100 | [diff] [blame] | 1198 | } |
| 1199 | } |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1200 | } else if (TLVP_PRESENT(tp, BSSGP_IE_LOCATION_AREA)) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1201 | errctr = GBPROX_GLOB_CTR_INV_LAI; |
Harald Welte | 3d1bd4d | 2020-11-23 15:14:20 +0100 | [diff] [blame] | 1202 | /* iterate over all peers and dispatch the paging to each matching one */ |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1203 | llist_for_each_entry(nse, &cfg->nse_peers, list) { |
| 1204 | llist_for_each_entry(peer, &nse->bts_peers, list) { |
| 1205 | if (!memcmp(peer->ra, TLVP_VAL(tp, BSSGP_IE_LOCATION_AREA), 5)) { |
| 1206 | LOGPC(DGPRS, LOGL_INFO, "routing by LAI to peer BVCI=%u\n", peer->bvci); |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 1207 | gbprox_relay2nse(msg, nse, ns_bvci); |
| 1208 | n_nses++; |
| 1209 | /* Only send it once to each NSE */ |
| 1210 | break; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1211 | } |
Harald Welte | 3d1bd4d | 2020-11-23 15:14:20 +0100 | [diff] [blame] | 1212 | } |
| 1213 | } |
Harald Welte | 53ee206 | 2020-11-24 11:31:13 +0100 | [diff] [blame] | 1214 | } else if (TLVP_PRESENT(tp, BSSGP_IE_BSS_AREA_ID)) { |
| 1215 | /* iterate over all peers and dispatch the paging to each matching one */ |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1216 | llist_for_each_entry(nse, &cfg->nse_peers, list) { |
| 1217 | llist_for_each_entry(peer, &nse->bts_peers, list) { |
| 1218 | LOGPC(DGPRS, LOGL_INFO, "broadcasting to peer BVCI=%u\n", peer->bvci); |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 1219 | gbprox_relay2nse(msg, nse, ns_bvci); |
| 1220 | n_nses++; |
| 1221 | /* Only send it once to each NSE */ |
| 1222 | break; |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1223 | } |
Harald Welte | 53ee206 | 2020-11-24 11:31:13 +0100 | [diff] [blame] | 1224 | } |
| 1225 | } else { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1226 | LOGPC(DGPRS, LOGL_INFO, "\n"); |
Harald Welte | 53ee206 | 2020-11-24 11:31:13 +0100 | [diff] [blame] | 1227 | LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(SGSN) BSSGP PAGING: " |
| 1228 | "unable to route, missing IE\n", nsei); |
| 1229 | rate_ctr_inc(&cfg->ctrg->ctr[errctr]); |
| 1230 | } |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1231 | |
Daniel Willmann | 7620571 | 2020-11-30 17:08:58 +0100 | [diff] [blame] | 1232 | if (n_nses == 0) { |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1233 | LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(SGSN) BSSGP PAGING: " |
Harald Welte | 53ee206 | 2020-11-24 11:31:13 +0100 | [diff] [blame] | 1234 | "unable to route, no destination found\n", nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1235 | rate_ctr_inc(&cfg->ctrg->ctr[errctr]); |
| 1236 | return -EINVAL; |
| 1237 | } |
Harald Welte | 3d1bd4d | 2020-11-23 15:14:20 +0100 | [diff] [blame] | 1238 | return 0; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1239 | } |
| 1240 | |
| 1241 | /* Receive an incoming BVC-RESET message from the SGSN */ |
| 1242 | static int rx_reset_from_sgsn(struct gbproxy_config *cfg, |
| 1243 | struct msgb *orig_msg, |
| 1244 | struct msgb *msg, struct tlv_parsed *tp, |
| 1245 | uint32_t nsei, uint16_t ns_bvci) |
| 1246 | { |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1247 | struct gbproxy_nse *nse; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1248 | struct gbproxy_peer *peer; |
| 1249 | uint16_t ptp_bvci; |
| 1250 | |
| 1251 | if (!TLVP_PRESENT(tp, BSSGP_IE_BVCI)) { |
| 1252 | rate_ctr_inc(&cfg->ctrg-> |
| 1253 | ctr[GBPROX_GLOB_CTR_PROTO_ERR_SGSN]); |
| 1254 | return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, |
| 1255 | NULL, orig_msg); |
| 1256 | } |
| 1257 | ptp_bvci = ntohs(tlvp_val16_unal(tp, BSSGP_IE_BVCI)); |
| 1258 | |
| 1259 | if (ptp_bvci >= 2) { |
| 1260 | /* A reset for a PTP BVC was received, forward it to its |
| 1261 | * respective peer */ |
| 1262 | peer = gbproxy_peer_by_bvci(cfg, ptp_bvci); |
| 1263 | if (!peer) { |
| 1264 | LOGP(DGPRS, LOGL_ERROR, "NSEI=%u BVCI=%u: Cannot find BSS\n", |
| 1265 | nsei, ptp_bvci); |
| 1266 | rate_ctr_inc(&cfg->ctrg-> |
| 1267 | ctr[GBPROX_GLOB_CTR_INV_BVCI]); |
| 1268 | return bssgp_tx_status(BSSGP_CAUSE_UNKNOWN_BVCI, |
| 1269 | &ptp_bvci, orig_msg); |
| 1270 | } |
| 1271 | return gbprox_relay2peer(msg, peer, ns_bvci); |
| 1272 | } |
| 1273 | |
| 1274 | /* A reset for the Signalling entity has been received |
| 1275 | * from the SGSN. As the signalling BVCI is shared |
| 1276 | * among all the BSS's that we multiplex, it needs to |
| 1277 | * be relayed */ |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1278 | llist_for_each_entry(nse, &cfg->nse_peers, list) { |
| 1279 | llist_for_each_entry(peer, &nse->bts_peers, list) |
| 1280 | gbprox_relay2peer(msg, peer, ns_bvci); |
| 1281 | } |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1282 | |
| 1283 | return 0; |
| 1284 | } |
| 1285 | |
| 1286 | /* Receive an incoming signalling message from the SGSN-side NS-VC */ |
| 1287 | static int gbprox_rx_sig_from_sgsn(struct gbproxy_config *cfg, |
| 1288 | struct msgb *orig_msg, uint32_t nsei, |
| 1289 | uint16_t ns_bvci) |
| 1290 | { |
| 1291 | struct bssgp_normal_hdr *bgph = |
| 1292 | (struct bssgp_normal_hdr *) msgb_bssgph(orig_msg); |
| 1293 | struct tlv_parsed tp; |
| 1294 | uint8_t pdu_type = bgph->pdu_type; |
| 1295 | int data_len; |
| 1296 | struct gbproxy_peer *peer; |
| 1297 | uint16_t bvci; |
| 1298 | struct msgb *msg; |
| 1299 | int rc = 0; |
| 1300 | int cause; |
| 1301 | |
| 1302 | if (ns_bvci != 0 && ns_bvci != 1) { |
| 1303 | LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u(SGSN) BVCI=%u is not " |
| 1304 | "signalling\n", nsei, ns_bvci); |
| 1305 | /* FIXME: Send proper error message */ |
| 1306 | return -EINVAL; |
| 1307 | } |
| 1308 | |
| 1309 | /* we actually should never see those two for BVCI == 0, but double-check |
| 1310 | * just to make sure */ |
| 1311 | if (pdu_type == BSSGP_PDUT_UL_UNITDATA || |
| 1312 | pdu_type == BSSGP_PDUT_DL_UNITDATA) { |
| 1313 | LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u(SGSN) UNITDATA not allowed in " |
| 1314 | "signalling\n", nsei); |
| 1315 | return bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, orig_msg); |
| 1316 | } |
| 1317 | |
| 1318 | msg = bssgp_msgb_copy(orig_msg, "rx_sig_from_sgsn"); |
| 1319 | gbprox_process_bssgp_dl(cfg, msg, NULL); |
| 1320 | /* Update message info */ |
| 1321 | bgph = (struct bssgp_normal_hdr *) msgb_bssgph(msg); |
| 1322 | data_len = msgb_bssgp_len(orig_msg) - sizeof(*bgph); |
| 1323 | rc = bssgp_tlv_parse(&tp, bgph->data, data_len); |
| 1324 | |
| 1325 | switch (pdu_type) { |
| 1326 | case BSSGP_PDUT_BVC_RESET: |
| 1327 | rc = rx_reset_from_sgsn(cfg, msg, orig_msg, &tp, nsei, ns_bvci); |
| 1328 | break; |
| 1329 | case BSSGP_PDUT_BVC_RESET_ACK: |
| 1330 | if (cfg->route_to_sgsn2 && nsei == cfg->nsip_sgsn2_nsei) |
| 1331 | break; |
Daniel Willmann | 8489e7a | 2020-11-03 21:12:42 +0100 | [diff] [blame] | 1332 | /* simple case: BVCI IE is mandatory */ |
| 1333 | if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI)) |
| 1334 | goto err_mand_ie; |
| 1335 | bvci = ntohs(tlvp_val16_unal(&tp, BSSGP_IE_BVCI)); |
| 1336 | if (bvci == BVCI_SIGNALLING) { |
| 1337 | /* TODO: Reset all PTP BVCIs */ |
| 1338 | } else { |
| 1339 | rc = gbprox_relay2bvci(cfg, msg, bvci, ns_bvci); |
| 1340 | } |
| 1341 | break; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1342 | case BSSGP_PDUT_FLUSH_LL: |
| 1343 | /* simple case: BVCI IE is mandatory */ |
| 1344 | if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI)) |
| 1345 | goto err_mand_ie; |
| 1346 | bvci = ntohs(tlvp_val16_unal(&tp, BSSGP_IE_BVCI)); |
| 1347 | rc = gbprox_relay2bvci(cfg, msg, bvci, ns_bvci); |
| 1348 | break; |
| 1349 | case BSSGP_PDUT_PAGING_PS: |
| 1350 | case BSSGP_PDUT_PAGING_CS: |
| 1351 | /* process the paging request (LAI/RAI lookup) */ |
| 1352 | rc = gbprox_rx_paging(cfg, msg, &tp, nsei, ns_bvci); |
| 1353 | break; |
| 1354 | case BSSGP_PDUT_STATUS: |
| 1355 | /* Some exception has occurred */ |
| 1356 | LOGP(DGPRS, LOGL_NOTICE, |
| 1357 | "NSEI=%u(SGSN) BSSGP STATUS ", nsei); |
| 1358 | if (!TLVP_PRESENT(&tp, BSSGP_IE_CAUSE)) { |
| 1359 | LOGPC(DGPRS, LOGL_NOTICE, "\n"); |
| 1360 | goto err_mand_ie; |
| 1361 | } |
| 1362 | cause = *TLVP_VAL(&tp, BSSGP_IE_CAUSE); |
| 1363 | LOGPC(DGPRS, LOGL_NOTICE, |
| 1364 | "cause=0x%02x(%s) ", *TLVP_VAL(&tp, BSSGP_IE_CAUSE), |
| 1365 | bssgp_cause_str(cause)); |
| 1366 | if (TLVP_PRESENT(&tp, BSSGP_IE_BVCI)) { |
| 1367 | bvci = ntohs(tlvp_val16_unal(&tp, BSSGP_IE_BVCI)); |
| 1368 | LOGPC(DGPRS, LOGL_NOTICE, "BVCI=%u\n", bvci); |
| 1369 | |
| 1370 | if (cause == BSSGP_CAUSE_UNKNOWN_BVCI) |
| 1371 | rc = gbprox_relay2bvci(cfg, msg, bvci, ns_bvci); |
| 1372 | } else |
| 1373 | LOGPC(DGPRS, LOGL_NOTICE, "\n"); |
| 1374 | break; |
| 1375 | /* those only exist in the SGSN -> BSS direction */ |
| 1376 | case BSSGP_PDUT_SUSPEND_ACK: |
| 1377 | case BSSGP_PDUT_SUSPEND_NACK: |
| 1378 | case BSSGP_PDUT_RESUME_ACK: |
| 1379 | case BSSGP_PDUT_RESUME_NACK: |
| 1380 | /* RAI IE is mandatory */ |
| 1381 | if (!TLVP_PRESENT(&tp, BSSGP_IE_ROUTEING_AREA)) |
| 1382 | goto err_mand_ie; |
| 1383 | peer = gbproxy_peer_by_rai(cfg, TLVP_VAL(&tp, BSSGP_IE_ROUTEING_AREA)); |
| 1384 | if (!peer) |
| 1385 | goto err_no_peer; |
| 1386 | rc = gbprox_relay2peer(msg, peer, ns_bvci); |
| 1387 | break; |
| 1388 | case BSSGP_PDUT_BVC_BLOCK_ACK: |
| 1389 | case BSSGP_PDUT_BVC_UNBLOCK_ACK: |
| 1390 | if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI)) |
| 1391 | goto err_mand_ie; |
| 1392 | bvci = ntohs(tlvp_val16_unal(&tp, BSSGP_IE_BVCI)); |
| 1393 | if (bvci == 0) { |
| 1394 | LOGP(DGPRS, LOGL_NOTICE, "NSEI=%u(SGSN) BSSGP " |
| 1395 | "%sBLOCK_ACK for signalling BVCI ?!?\n", nsei, |
| 1396 | pdu_type == BSSGP_PDUT_BVC_UNBLOCK_ACK ? "UN":""); |
| 1397 | /* should we send STATUS ? */ |
| 1398 | rate_ctr_inc(&cfg->ctrg-> |
| 1399 | ctr[GBPROX_GLOB_CTR_INV_BVCI]); |
| 1400 | } else { |
| 1401 | /* Mark BVC as (un)blocked */ |
| 1402 | block_unblock_peer(cfg, bvci, pdu_type); |
| 1403 | } |
| 1404 | rc = gbprox_relay2bvci(cfg, msg, bvci, ns_bvci); |
| 1405 | break; |
| 1406 | case BSSGP_PDUT_SGSN_INVOKE_TRACE: |
| 1407 | LOGP(DGPRS, LOGL_ERROR, |
| 1408 | "NSEI=%u(SGSN) BSSGP INVOKE TRACE not supported\n",nsei); |
| 1409 | rate_ctr_inc(&cfg->ctrg-> |
| 1410 | ctr[GBPROX_GLOB_CTR_NOT_SUPPORTED_SGSN]); |
| 1411 | rc = bssgp_tx_status(BSSGP_CAUSE_PDU_INCOMP_FEAT, NULL, orig_msg); |
| 1412 | break; |
| 1413 | default: |
| 1414 | LOGP(DGPRS, LOGL_NOTICE, "BSSGP PDU type %s not supported\n", bssgp_pdu_str(pdu_type)); |
| 1415 | rate_ctr_inc(&cfg->ctrg-> |
| 1416 | ctr[GBPROX_GLOB_CTR_PROTO_ERR_SGSN]); |
| 1417 | rc = bssgp_tx_status(BSSGP_CAUSE_PROTO_ERR_UNSPEC, NULL, orig_msg); |
| 1418 | break; |
| 1419 | } |
| 1420 | |
| 1421 | msgb_free(msg); |
| 1422 | |
| 1423 | return rc; |
| 1424 | err_mand_ie: |
| 1425 | LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(SGSN) missing mandatory IE\n", |
| 1426 | nsei); |
| 1427 | rate_ctr_inc(&cfg->ctrg-> |
| 1428 | ctr[GBPROX_GLOB_CTR_PROTO_ERR_SGSN]); |
| 1429 | msgb_free(msg); |
| 1430 | return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, orig_msg); |
| 1431 | err_no_peer: |
| 1432 | LOGP(DGPRS, LOGL_ERROR, "NSEI=%u(SGSN) cannot find peer based on RAI\n", |
| 1433 | nsei); |
| 1434 | rate_ctr_inc(&cfg->ctrg-> ctr[GBPROX_GLOB_CTR_INV_RAI]); |
| 1435 | msgb_free(msg); |
| 1436 | return bssgp_tx_status(BSSGP_CAUSE_INV_MAND_INF, NULL, orig_msg); |
| 1437 | } |
| 1438 | |
| 1439 | static int gbproxy_is_sgsn_nsei(struct gbproxy_config *cfg, uint16_t nsei) |
| 1440 | { |
| 1441 | return nsei == cfg->nsip_sgsn_nsei || |
| 1442 | (cfg->route_to_sgsn2 && nsei == cfg->nsip_sgsn2_nsei); |
| 1443 | } |
| 1444 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1445 | int gbprox_bssgp_send_cb(void *ctx, struct msgb *msg) |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1446 | { |
| 1447 | int rc; |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1448 | struct gbproxy_config *cfg = (struct gbproxy_config *) ctx; |
| 1449 | struct gprs_ns2_inst *nsi = cfg->nsi; |
| 1450 | struct osmo_gprs_ns2_prim nsp = {}; |
| 1451 | |
| 1452 | nsp.bvci = msgb_bvci(msg); |
| 1453 | nsp.nsei = msgb_nsei(msg); |
| 1454 | |
| 1455 | osmo_prim_init(&nsp.oph, SAP_NS, PRIM_NS_UNIT_DATA, PRIM_OP_REQUEST, msg); |
| 1456 | rc = gprs_ns2_recv_prim(nsi, &nsp.oph); |
| 1457 | |
| 1458 | return rc; |
| 1459 | } |
| 1460 | |
| 1461 | /* Main input function for Gb proxy */ |
| 1462 | int gbprox_rcvmsg(void *ctx, struct msgb *msg) |
| 1463 | { |
| 1464 | int rc; |
| 1465 | uint16_t nsei = msgb_nsei(msg); |
| 1466 | uint16_t ns_bvci = msgb_bvci(msg); |
| 1467 | struct gbproxy_config *cfg = (struct gbproxy_config *) ctx; |
| 1468 | |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1469 | int remote_end_is_sgsn = gbproxy_is_sgsn_nsei(cfg, nsei); |
| 1470 | |
| 1471 | /* Only BVCI=0 messages need special treatment */ |
| 1472 | if (ns_bvci == 0 || ns_bvci == 1) { |
| 1473 | if (remote_end_is_sgsn) |
| 1474 | rc = gbprox_rx_sig_from_sgsn(cfg, msg, nsei, ns_bvci); |
| 1475 | else |
| 1476 | rc = gbprox_rx_sig_from_bss(cfg, msg, nsei, ns_bvci); |
| 1477 | } else { |
| 1478 | /* All other BVCI are PTP */ |
| 1479 | if (remote_end_is_sgsn) |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1480 | rc = gbprox_rx_ptp_from_sgsn(cfg, msg, nsei, |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1481 | ns_bvci); |
| 1482 | else |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1483 | rc = gbprox_rx_ptp_from_bss(cfg, msg, nsei, |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1484 | ns_bvci); |
| 1485 | } |
| 1486 | |
| 1487 | return rc; |
| 1488 | } |
| 1489 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1490 | /* TODO: What about handling: |
| 1491 | * NS_AFF_CAUSE_VC_FAILURE, |
| 1492 | NS_AFF_CAUSE_VC_RECOVERY, |
| 1493 | NS_AFF_CAUSE_FAILURE, |
| 1494 | NS_AFF_CAUSE_RECOVERY, |
| 1495 | osmocom own causes |
| 1496 | NS_AFF_CAUSE_SNS_CONFIGURED, |
| 1497 | NS_AFF_CAUSE_SNS_FAILURE, |
| 1498 | */ |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1499 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1500 | void gprs_ns_prim_status_cb(struct gbproxy_config *cfg, struct osmo_gprs_ns2_prim *nsp) |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1501 | { |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1502 | /* TODO: bss nsei available/unavailable bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_BLOCK, nsvc->nsei, peer->bvci, 0); |
| 1503 | * TODO: sgsn nsei available/unavailable |
| 1504 | */ |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1505 | struct gbproxy_peer *peer; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1506 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1507 | switch (nsp->u.status.cause) { |
| 1508 | case NS_AFF_CAUSE_SNS_FAILURE: |
| 1509 | case NS_AFF_CAUSE_SNS_CONFIGURED: |
| 1510 | break; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1511 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1512 | case NS_AFF_CAUSE_RECOVERY: |
| 1513 | LOGP(DPCU, LOGL_NOTICE, "NS-NSE %d became available\n", nsp->nsei); |
| 1514 | if (nsp->nsei == cfg->nsip_sgsn_nsei) { |
| 1515 | /* look-up or create the BTS context for this BVC */ |
| 1516 | struct bssgp_bvc_ctx *bctx = btsctx_by_bvci_nsei(nsp->bvci, nsp->nsei); |
| 1517 | if (!bctx) |
| 1518 | bctx = btsctx_alloc(nsp->bvci, nsp->nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1519 | |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1520 | bssgp_tx_bvc_reset_nsei_bvci(cfg->nsip_sgsn_nsei, 0, BSSGP_CAUSE_OML_INTERV, NULL, 0); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1521 | } |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1522 | break; |
| 1523 | case NS_AFF_CAUSE_FAILURE: |
| 1524 | if (nsp->nsei == cfg->nsip_sgsn_nsei) { |
| 1525 | /* sgsn */ |
| 1526 | /* TODO: BSVC: block all PtP towards bss */ |
| 1527 | rate_ctr_inc(&cfg->ctrg-> |
| 1528 | ctr[GBPROX_GLOB_CTR_RESTART_RESET_SGSN]); |
| 1529 | } else { |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1530 | /* bss became unavailable |
| 1531 | * TODO: Block all BVC belonging to that NSE */ |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1532 | peer = gbproxy_peer_by_nsei(cfg, nsp->nsei); |
| 1533 | if (!peer) { |
| 1534 | /* TODO: use primitive name + status cause name */ |
| 1535 | LOGP(DGPRS, LOGL_NOTICE, "Received ns2 primitive %d for unknown peer NSEI=%u\n", |
| 1536 | nsp->u.status.cause, nsp->nsei); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1537 | break; |
| 1538 | } |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1539 | |
| 1540 | if (!peer->blocked) |
| 1541 | break; |
| 1542 | bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_BLOCK, cfg->nsip_sgsn_nsei, |
| 1543 | peer->bvci, 0); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1544 | } |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1545 | LOGP(DPCU, LOGL_NOTICE, "NS-NSE %d became unavailable\n", nsp->nsei); |
| 1546 | break; |
| 1547 | default: |
Harald Welte | 95cf9fb | 2020-11-30 10:55:22 +0100 | [diff] [blame] | 1548 | LOGP(DPCU, LOGL_NOTICE, "NS: Unknown NS-STATUS.ind cause=%s from NS\n", |
| 1549 | gprs_ns2_aff_cause_prim_str(nsp->u.status.cause)); |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1550 | break; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1551 | } |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1552 | } |
| 1553 | |
| 1554 | |
| 1555 | /* called by the ns layer */ |
| 1556 | int gprs_ns2_prim_cb(struct osmo_prim_hdr *oph, void *ctx) |
| 1557 | { |
| 1558 | struct osmo_gprs_ns2_prim *nsp; |
| 1559 | struct gbproxy_config *cfg = (struct gbproxy_config *) ctx; |
| 1560 | int rc = 0; |
| 1561 | |
| 1562 | if (oph->sap != SAP_NS) |
| 1563 | return 0; |
| 1564 | |
| 1565 | nsp = container_of(oph, struct osmo_gprs_ns2_prim, oph); |
| 1566 | |
| 1567 | if (oph->operation != PRIM_OP_INDICATION) { |
Harald Welte | 95cf9fb | 2020-11-30 10:55:22 +0100 | [diff] [blame] | 1568 | LOGP(DPCU, LOGL_NOTICE, "NS: Unexpected primitive operation %s from NS\n", |
| 1569 | get_value_string(osmo_prim_op_names, oph->operation)); |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1570 | return 0; |
| 1571 | } |
| 1572 | |
| 1573 | switch (oph->primitive) { |
| 1574 | case PRIM_NS_UNIT_DATA: |
| 1575 | /* hand the message into the BSSGP implementation */ |
| 1576 | msgb_bssgph(oph->msg) = oph->msg->l3h; |
| 1577 | msgb_bvci(oph->msg) = nsp->bvci; |
| 1578 | msgb_nsei(oph->msg) = nsp->nsei; |
| 1579 | |
| 1580 | rc = gbprox_rcvmsg(cfg, oph->msg); |
Daniel Willmann | b655010 | 2020-11-04 17:32:56 +0100 | [diff] [blame] | 1581 | msgb_free(oph->msg); |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1582 | break; |
| 1583 | case PRIM_NS_STATUS: |
| 1584 | gprs_ns_prim_status_cb(cfg, nsp); |
| 1585 | break; |
| 1586 | default: |
Harald Welte | 95cf9fb | 2020-11-30 10:55:22 +0100 | [diff] [blame] | 1587 | LOGP(DPCU, LOGL_NOTICE, "NS: Unknown prim %s %s from NS\n", |
| 1588 | gprs_ns2_prim_str(oph->primitive), |
| 1589 | get_value_string(osmo_prim_op_names, oph->operation)); |
Alexander Couzens | 951e133 | 2020-09-22 13:21:46 +0200 | [diff] [blame] | 1590 | break; |
| 1591 | } |
| 1592 | |
| 1593 | return rc; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1594 | } |
| 1595 | |
| 1596 | void gbprox_reset(struct gbproxy_config *cfg) |
| 1597 | { |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1598 | struct gbproxy_nse *nse, *ntmp; |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1599 | |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1600 | llist_for_each_entry_safe(nse, ntmp, &cfg->nse_peers, list) { |
| 1601 | struct gbproxy_peer *peer, *tmp; |
| 1602 | llist_for_each_entry_safe(peer, tmp, &nse->bts_peers, list) |
| 1603 | gbproxy_peer_free(peer); |
| 1604 | |
| 1605 | gbproxy_nse_free(nse); |
| 1606 | } |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1607 | |
| 1608 | rate_ctr_group_free(cfg->ctrg); |
| 1609 | gbproxy_init_config(cfg); |
| 1610 | } |
| 1611 | |
| 1612 | int gbproxy_init_config(struct gbproxy_config *cfg) |
| 1613 | { |
| 1614 | struct timespec tp; |
| 1615 | |
Daniel Willmann | e50550e | 2020-11-26 18:19:21 +0100 | [diff] [blame] | 1616 | INIT_LLIST_HEAD(&cfg->nse_peers); |
Pau Espin Pedrol | 1ddefb1 | 2019-08-30 19:48:34 +0200 | [diff] [blame] | 1617 | cfg->ctrg = rate_ctr_group_alloc(tall_sgsn_ctx, &global_ctrg_desc, 0); |
| 1618 | if (!cfg->ctrg) { |
| 1619 | LOGP(DGPRS, LOGL_ERROR, "Cannot allocate global counter group!\n"); |
| 1620 | return -1; |
| 1621 | } |
| 1622 | osmo_clock_gettime(CLOCK_REALTIME, &tp); |
| 1623 | |
| 1624 | return 0; |
| 1625 | } |