Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 1 | /* OpenBSC minimal LAPD implementation */ |
| 2 | |
| 3 | /* (C) 2009 by oystein@homelien.no |
| 4 | * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org> |
| 5 | * (C) 2010 by Digium and Matthew Fredrickson <creslin@digium.com> |
| 6 | * (C) 2011 by Harald Welte <laforge@gnumonks.org> |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 7 | * (C) 2011 by Andreas Eversberg <jolly@eversberg.eu> |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 8 | * |
| 9 | * All Rights Reserved |
| 10 | * |
Harald Welte | 323d39d | 2017-11-13 01:09:21 +0900 | [diff] [blame] | 11 | * SPDX-License-Identifier: GPL-2.0+ |
| 12 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 13 | * This program is free software; you can redistribute it and/or modify |
| 14 | * it under the terms of the GNU General Public License as published by |
| 15 | * the Free Software Foundation; either version 2 of the License, or |
| 16 | * (at your option) any later version. |
| 17 | * |
| 18 | * This program is distributed in the hope that it will be useful, |
| 19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 21 | * GNU General Public License for more details. |
| 22 | * |
| 23 | * You should have received a copy of the GNU General Public License along |
| 24 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 25 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 26 | * |
| 27 | */ |
| 28 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 29 | #include "internal.h" |
| 30 | |
| 31 | #include <stdio.h> |
| 32 | #include <string.h> |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 33 | #include <errno.h> |
| 34 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 35 | #include <osmocom/core/linuxlist.h> |
| 36 | #include <osmocom/core/logging.h> |
Harald Welte | 71d87b2 | 2011-07-18 14:49:56 +0200 | [diff] [blame] | 37 | #include <osmocom/core/talloc.h> |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 38 | #include <osmocom/core/msgb.h> |
| 39 | #include <osmocom/core/timer.h> |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 40 | #include <osmocom/abis/lapd.h> |
Pablo Neira Ayuso | 9530600 | 2012-08-22 16:43:59 +0200 | [diff] [blame] | 41 | #include <osmocom/abis/lapd_pcap.h> |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 42 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 43 | #define LAPD_ADDR2(sapi, cr) ((((sapi) & 0x3f) << 2) | (((cr) & 0x1) << 1)) |
| 44 | #define LAPD_ADDR3(tei) ((((tei) & 0x7f) << 1) | 0x1) |
| 45 | |
| 46 | #define LAPD_ADDR_SAPI(addr) ((addr) >> 2) |
| 47 | #define LAPD_ADDR_CR(addr) (((addr) >> 1) & 0x1) |
| 48 | #define LAPD_ADDR_EA(addr) ((addr) & 0x1) |
| 49 | #define LAPD_ADDR_TEI(addr) ((addr) >> 1) |
| 50 | |
| 51 | #define LAPD_CTRL_I4(ns) (((ns) & 0x7f) << 1) |
| 52 | #define LAPD_CTRL_I5(nr, p) ((((nr) & 0x7f) << 1) | ((p) & 0x1)) |
| 53 | #define LAPD_CTRL_S4(s) ((((s) & 0x3) << 2) | 0x1) |
| 54 | #define LAPD_CTRL_S5(nr, p) ((((nr) & 0x7f) << 1) | ((p) & 0x1)) |
| 55 | #define LAPD_CTRL_U4(u, p) ((((u) & 0x1c) << (5-2)) | (((p) & 0x1) << 4) | (((u) & 0x3) << 2) | 0x3) |
| 56 | |
| 57 | #define LAPD_CTRL_is_I(ctrl) (((ctrl) & 0x1) == 0) |
| 58 | #define LAPD_CTRL_is_S(ctrl) (((ctrl) & 0x3) == 1) |
| 59 | #define LAPD_CTRL_is_U(ctrl) (((ctrl) & 0x3) == 3) |
| 60 | |
| 61 | #define LAPD_CTRL_U_BITS(ctrl) ((((ctrl) & 0xC) >> 2) | ((ctrl) & 0xE0) >> 3) |
| 62 | #define LAPD_CTRL_U_PF(ctrl) (((ctrl) >> 4) & 0x1) |
| 63 | |
| 64 | #define LAPD_CTRL_S_BITS(ctrl) (((ctrl) & 0xC) >> 2) |
| 65 | #define LAPD_CTRL_S_PF(ctrl) (ctrl & 0x1) |
| 66 | |
| 67 | #define LAPD_CTRL_I_Ns(ctrl) (((ctrl) & 0xFE) >> 1) |
| 68 | #define LAPD_CTRL_I_P(ctrl) (ctrl & 0x1) |
| 69 | #define LAPD_CTRL_Nr(ctrl) (((ctrl) & 0xFE) >> 1) |
| 70 | |
| 71 | #define LAPD_LEN(len) ((len << 2) | 0x1) |
| 72 | #define LAPD_EL 0x1 |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 73 | |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame] | 74 | #define LAPD_SET_K(n, o) {n,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o} |
| 75 | |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 76 | #define LOGLI(li, level, fmt, args ...) \ |
| 77 | LOGP(DLLAPD, level, "%s: " fmt, (li)->name, ## args) |
| 78 | |
| 79 | #define LOGTEI(teip, level, fmt, args ...) \ |
| 80 | LOGP(DLLAPD, level, "(%s-T%u): " fmt, (teip)->li->name, (teip)->tei, ## args) |
| 81 | |
| 82 | #define LOGSAP(sap, level, fmt, args ...) \ |
| 83 | LOGP(DLLAPD, level, "%s: " fmt, (sap)->dl.name, ## args) |
| 84 | |
Harald Welte | 47c247b | 2020-07-03 19:05:44 +0200 | [diff] [blame] | 85 | #define DLSAP_MSGB_SIZE 128 |
Harald Welte | ea7da44 | 2020-07-03 19:05:07 +0200 | [diff] [blame] | 86 | #define DLSAP_MSGB_HEADROOM 56 |
| 87 | |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 88 | const struct lapd_profile lapd_profile_isdn = { |
Pablo Neira Ayuso | f42280b | 2012-03-12 18:17:31 +0100 | [diff] [blame] | 89 | .k = LAPD_SET_K(7,7), |
| 90 | .n200 = 3, |
| 91 | .n201 = 260, |
| 92 | .n202 = 3, |
| 93 | .t200_sec = 1, .t200_usec = 0, |
| 94 | .t201_sec = 1, .t201_usec = 0, |
| 95 | .t202_sec = 2, .t202_usec = 0, |
| 96 | .t203_sec = 10, .t203_usec = 0, |
| 97 | .short_address = 0 |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 98 | }; |
| 99 | |
| 100 | const struct lapd_profile lapd_profile_abis = { |
Pablo Neira Ayuso | f42280b | 2012-03-12 18:17:31 +0100 | [diff] [blame] | 101 | .k = LAPD_SET_K(2,1), |
| 102 | .n200 = 3, |
| 103 | .n201 = 260, |
| 104 | .n202 = 0, /* infinite */ |
| 105 | .t200_sec = 0, .t200_usec = 240000, |
| 106 | .t201_sec = 1, .t201_usec = 0, |
| 107 | .t202_sec = 2, .t202_usec = 0, |
| 108 | .t203_sec = 10, .t203_usec = 0, |
| 109 | .short_address = 0 |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 110 | }; |
| 111 | |
Philipp | 0c7d5f4 | 2016-10-19 18:38:58 +0200 | [diff] [blame] | 112 | /* Ericssons OM2000 lapd dialect requires a sabm frame retransmission |
| 113 | * timeout of exactly 300 msek. Shorter or longer retransmission will |
| 114 | * cause the link establishment to fail permanently. Since the BTS is |
| 115 | * periodically scanning through all timeslots to find the timeslot |
| 116 | * where the bsc is transmitting its sabm frames the normal maximum |
| 117 | * retransmission (n200) of 3 is not enough. In order not to miss |
Philipp Maier | d75bac4 | 2017-02-01 13:51:03 +0100 | [diff] [blame] | 118 | * the bts, n200 has been increased to 50, which is an educated |
Philipp | 0c7d5f4 | 2016-10-19 18:38:58 +0200 | [diff] [blame] | 119 | * guess. */ |
| 120 | |
| 121 | const struct lapd_profile lapd_profile_abis_ericsson = { |
| 122 | .k = LAPD_SET_K(2,1), |
Philipp Maier | d75bac4 | 2017-02-01 13:51:03 +0100 | [diff] [blame] | 123 | .n200 = 50, |
Philipp | 0c7d5f4 | 2016-10-19 18:38:58 +0200 | [diff] [blame] | 124 | .n201 = 260, |
| 125 | .n202 = 0, /* infinite */ |
| 126 | .t200_sec = 0, .t200_usec = 300000, |
| 127 | .t201_sec = 1, .t201_usec = 0, |
| 128 | .t202_sec = 2, .t202_usec = 0, |
| 129 | .t203_sec = 10, .t203_usec = 0, |
| 130 | .short_address = 0 |
| 131 | }; |
| 132 | |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 133 | const struct lapd_profile lapd_profile_sat = { |
Pablo Neira Ayuso | f42280b | 2012-03-12 18:17:31 +0100 | [diff] [blame] | 134 | .k = LAPD_SET_K(15,15), |
| 135 | .n200 = 5, |
| 136 | .n201 = 260, |
| 137 | .n202 = 5, |
| 138 | .t200_sec = 2, .t200_usec = 400000, |
| 139 | .t201_sec = 2, .t201_usec = 400000, |
| 140 | .t202_sec = 2, .t202_usec = 400000, |
Holger Hans Peter Freyther | 4b6860d | 2013-03-09 17:32:33 +0100 | [diff] [blame] | 141 | .t203_sec = 20, .t203_usec = 0, |
Pablo Neira Ayuso | f42280b | 2012-03-12 18:17:31 +0100 | [diff] [blame] | 142 | .short_address = 1 |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 143 | }; |
| 144 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 145 | typedef enum { |
| 146 | LAPD_TEI_NONE = 0, |
| 147 | LAPD_TEI_ASSIGNED, |
| 148 | LAPD_TEI_ACTIVE, |
| 149 | } lapd_tei_state; |
| 150 | |
| 151 | const char *lapd_tei_states[] = { |
| 152 | "NONE", |
| 153 | "ASSIGNED", |
| 154 | "ACTIVE", |
| 155 | }; |
| 156 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 157 | /* Structure representing an allocated TEI within a LAPD instance. */ |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 158 | struct lapd_tei { |
| 159 | struct llist_head list; |
| 160 | struct lapd_instance *li; |
| 161 | uint8_t tei; |
| 162 | lapd_tei_state state; |
| 163 | |
| 164 | struct llist_head sap_list; |
| 165 | }; |
| 166 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 167 | /* Structure representing a SAP within a TEI. It includes exactly one datalink |
| 168 | * instance. */ |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 169 | struct lapd_sap { |
| 170 | struct llist_head list; |
| 171 | struct lapd_tei *tei; |
| 172 | uint8_t sapi; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 173 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 174 | struct lapd_datalink dl; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 175 | }; |
| 176 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 177 | /* Resolve TEI structure from given numeric TEI */ |
| 178 | static struct lapd_tei *teip_from_tei(struct lapd_instance *li, uint8_t tei) |
| 179 | { |
| 180 | struct lapd_tei *lt; |
| 181 | |
| 182 | llist_for_each_entry(lt, &li->tei_list, list) { |
| 183 | if (lt->tei == tei) |
| 184 | return lt; |
| 185 | } |
| 186 | return NULL; |
| 187 | }; |
| 188 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 189 | /* Change state of TEI */ |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 190 | static void lapd_tei_set_state(struct lapd_tei *teip, int newstate) |
| 191 | { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 192 | LOGTEI(teip, LOGL_INFO, "LAPD state change on TEI %d: %s -> %s\n", |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 193 | teip->tei, lapd_tei_states[teip->state], |
| 194 | lapd_tei_states[newstate]); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 195 | teip->state = newstate; |
| 196 | }; |
| 197 | |
| 198 | /* Allocate a new TEI */ |
| 199 | struct lapd_tei *lapd_tei_alloc(struct lapd_instance *li, uint8_t tei) |
| 200 | { |
| 201 | struct lapd_tei *teip; |
| 202 | |
| 203 | teip = talloc_zero(li, struct lapd_tei); |
| 204 | if (!teip) |
| 205 | return NULL; |
| 206 | |
| 207 | teip->li = li; |
| 208 | teip->tei = tei; |
| 209 | llist_add(&teip->list, &li->tei_list); |
| 210 | INIT_LLIST_HEAD(&teip->sap_list); |
| 211 | |
| 212 | lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED); |
| 213 | |
| 214 | return teip; |
| 215 | } |
| 216 | |
| 217 | /* Find a SAP within a given TEI */ |
| 218 | static struct lapd_sap *lapd_sap_find(struct lapd_tei *teip, uint8_t sapi) |
| 219 | { |
| 220 | struct lapd_sap *sap; |
| 221 | |
| 222 | llist_for_each_entry(sap, &teip->sap_list, list) { |
| 223 | if (sap->sapi == sapi) |
| 224 | return sap; |
| 225 | } |
| 226 | |
| 227 | return NULL; |
| 228 | } |
| 229 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 230 | static int send_ph_data_req(struct lapd_msg_ctx *lctx, struct msgb *msg); |
| 231 | static int send_dlsap(struct osmo_dlsap_prim *dp, struct lapd_msg_ctx *lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 232 | |
| 233 | /* Allocate a new SAP within a given TEI */ |
| 234 | static struct lapd_sap *lapd_sap_alloc(struct lapd_tei *teip, uint8_t sapi) |
| 235 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 236 | struct lapd_sap *sap; |
| 237 | struct lapd_datalink *dl; |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 238 | struct lapd_instance *li = teip->li; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 239 | struct lapd_profile *profile; |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 240 | char name[256]; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 241 | int k; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 242 | |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 243 | snprintf(name, sizeof(name), "(%s-T%u-S%u)", li->name, teip->tei, sapi); |
| 244 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 245 | sap = talloc_zero(teip, struct lapd_sap); |
| 246 | if (!sap) |
| 247 | return NULL; |
| 248 | |
Philipp Maier | 027e119 | 2016-12-08 17:17:33 +0100 | [diff] [blame] | 249 | LOGP(DLLAPD, LOGL_NOTICE, |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 250 | "%s: LAPD Allocating SAP for SAPI=%u / TEI=%u (dl=%p, sap=%p)\n", |
| 251 | name, sapi, teip->tei, &sap->dl, sap); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 252 | |
| 253 | sap->sapi = sapi; |
| 254 | sap->tei = teip; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 255 | dl = &sap->dl; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 256 | profile = &li->profile; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 257 | |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame] | 258 | k = profile->k[sapi & 0x3f]; |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 259 | LOGP(DLLAPD, LOGL_NOTICE, "%s: k=%d N200=%d N201=%d T200=%d.%d T203=%d.%d\n", |
| 260 | name, k, profile->n200, profile->n201, profile->t200_sec, |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame] | 261 | profile->t200_usec, profile->t203_sec, profile->t203_usec); |
Pau Espin Pedrol | ffc92d5 | 2020-07-15 15:27:40 +0200 | [diff] [blame] | 262 | lapd_dl_init2(dl, k, 128, profile->n201, name); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 263 | dl->use_sabme = 1; /* use SABME instead of SABM (GSM) */ |
| 264 | dl->send_ph_data_req = send_ph_data_req; |
| 265 | dl->send_dlsap = send_dlsap; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 266 | dl->n200 = profile->n200; |
| 267 | dl->n200_est_rel = profile->n200; |
| 268 | dl->t200_sec = profile->t200_sec; dl->t200_usec = profile->t200_usec; |
| 269 | dl->t203_sec = profile->t203_sec; dl->t203_usec = profile->t203_usec; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 270 | dl->lctx.dl = &sap->dl; |
| 271 | dl->lctx.sapi = sapi; |
| 272 | dl->lctx.tei = teip->tei; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 273 | dl->lctx.n201 = profile->n201; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 274 | |
| 275 | lapd_set_mode(&sap->dl, (teip->li->network_side) ? LAPD_MODE_NETWORK |
| 276 | : LAPD_MODE_USER); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 277 | |
| 278 | llist_add(&sap->list, &teip->sap_list); |
| 279 | |
| 280 | return sap; |
| 281 | } |
| 282 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 283 | /* Free SAP instance, including the datalink */ |
| 284 | static void lapd_sap_free(struct lapd_sap *sap) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 285 | { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 286 | LOGSAP(sap, LOGL_NOTICE, |
Philipp Maier | 027e119 | 2016-12-08 17:17:33 +0100 | [diff] [blame] | 287 | "LAPD Freeing SAP for SAPI=%u / TEI=%u (dl=%p, sap=%p)\n", |
| 288 | sap->sapi, sap->tei->tei, &sap->dl, sap); |
| 289 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 290 | /* free datalink structures and timers */ |
| 291 | lapd_dl_exit(&sap->dl); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 292 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 293 | llist_del(&sap->list); |
| 294 | talloc_free(sap); |
| 295 | } |
| 296 | |
| 297 | /* Free TEI instance */ |
| 298 | static void lapd_tei_free(struct lapd_tei *teip) |
| 299 | { |
| 300 | struct lapd_sap *sap, *sap2; |
| 301 | |
| 302 | llist_for_each_entry_safe(sap, sap2, &teip->sap_list, list) { |
| 303 | lapd_sap_free(sap); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 304 | } |
| 305 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 306 | llist_del(&teip->list); |
| 307 | talloc_free(teip); |
| 308 | } |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 309 | |
| 310 | /* Input function into TEI manager */ |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 311 | static int lapd_tei_receive(struct lapd_instance *li, uint8_t *data, int len) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 312 | { |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 313 | uint8_t entity; |
| 314 | uint8_t ref; |
| 315 | uint8_t mt; |
| 316 | uint8_t action; |
| 317 | uint8_t e; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 318 | uint8_t resp[8]; |
| 319 | struct lapd_tei *teip; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 320 | struct msgb *msg; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 321 | |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 322 | if (len < 5) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 323 | LOGLI(li, LOGL_ERROR, "LAPD TEIMGR frame receive len %d < 5" |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 324 | ", ignoring\n", len); |
| 325 | return -EINVAL; |
| 326 | }; |
| 327 | |
| 328 | entity = data[0]; |
| 329 | ref = data[1]; |
| 330 | mt = data[3]; |
| 331 | action = data[4] >> 1; |
| 332 | e = data[4] & 1; |
| 333 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 334 | DEBUGP(DLLAPD, "LAPD TEIMGR: entity %x, ref %x, mt %x, action %x, " |
| 335 | "e %x\n", entity, ref, mt, action, e); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 336 | |
| 337 | switch (mt) { |
| 338 | case 0x01: /* IDENTITY REQUEST */ |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 339 | DEBUGP(DLLAPD, "LAPD TEIMGR: identity request for TEI %u\n", |
| 340 | action); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 341 | |
| 342 | teip = teip_from_tei(li, action); |
| 343 | if (!teip) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 344 | LOGLI(li, LOGL_INFO, "TEI MGR: New TEI %u\n", |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 345 | action); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 346 | teip = lapd_tei_alloc(li, action); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 347 | if (!teip) |
| 348 | return -ENOMEM; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 349 | } |
| 350 | |
| 351 | /* Send ACCEPT */ |
| 352 | memmove(resp, "\xfe\xff\x03\x0f\x00\x00\x02\x00", 8); |
| 353 | resp[7] = (action << 1) | 1; |
Harald Welte | ea7da44 | 2020-07-03 19:05:07 +0200 | [diff] [blame] | 354 | msg = msgb_alloc_headroom(DLSAP_MSGB_SIZE, DLSAP_MSGB_HEADROOM, "DL EST"); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 355 | msg->l2h = msgb_push(msg, 8); |
| 356 | memcpy(msg->l2h, resp, 8); |
Pablo Neira Ayuso | 9530600 | 2012-08-22 16:43:59 +0200 | [diff] [blame] | 357 | |
| 358 | /* write to PCAP file, if enabled. */ |
| 359 | osmo_pcap_lapd_write(li->pcap_fd, OSMO_LAPD_PCAP_OUTPUT, msg); |
| 360 | |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 361 | LOGTEI(teip, LOGL_DEBUG, "TX: %s\n", osmo_hexdump(msg->data, msg->len)); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 362 | li->transmit_cb(msg, li->transmit_cbdata); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 363 | |
| 364 | if (teip->state == LAPD_TEI_NONE) |
| 365 | lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED); |
| 366 | break; |
| 367 | default: |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 368 | LOGLI(li, LOGL_NOTICE, "LAPD TEIMGR: unknown mt %x action %x\n", mt, action); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 369 | break; |
| 370 | }; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 371 | |
| 372 | return 0; |
| 373 | } |
| 374 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 375 | /* General input function for any data received for this LAPD instance */ |
| 376 | int lapd_receive(struct lapd_instance *li, struct msgb *msg, int *error) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 377 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 378 | int i; |
| 379 | struct lapd_msg_ctx lctx; |
| 380 | int rc; |
| 381 | struct lapd_sap *sap; |
| 382 | struct lapd_tei *teip; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 383 | |
Pablo Neira Ayuso | 9530600 | 2012-08-22 16:43:59 +0200 | [diff] [blame] | 384 | /* write to PCAP file, if enabled. */ |
| 385 | osmo_pcap_lapd_write(li->pcap_fd, OSMO_LAPD_PCAP_INPUT, msg); |
| 386 | |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 387 | LOGLI(li, LOGL_DEBUG, "RX: %s\n", osmo_hexdump(msg->data, msg->len)); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 388 | if (msg->len < 2) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 389 | LOGLI(li, LOGL_ERROR, "LAPD frame receive len %d < 2, ignoring\n", msg->len); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 390 | *error = LAPD_ERR_BAD_LEN; |
| 391 | return -EINVAL; |
| 392 | }; |
| 393 | msg->l2h = msg->data; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 394 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 395 | memset(&lctx, 0, sizeof(lctx)); |
| 396 | |
| 397 | i = 0; |
| 398 | /* adress field */ |
| 399 | lctx.sapi = LAPD_ADDR_SAPI(msg->l2h[i]); |
| 400 | lctx.cr = LAPD_ADDR_CR(msg->l2h[i]); |
| 401 | lctx.lpd = 0; |
| 402 | if (!LAPD_ADDR_EA(msg->l2h[i])) { |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 403 | if (msg->len < 3) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 404 | LOGLI(li, LOGL_ERROR, "LAPD frame with TEI receive " |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 405 | "len %d < 3, ignoring\n", msg->len); |
| 406 | *error = LAPD_ERR_BAD_LEN; |
| 407 | return -EINVAL; |
| 408 | }; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 409 | i++; |
| 410 | lctx.tei = LAPD_ADDR_TEI(msg->l2h[i]); |
| 411 | } |
| 412 | i++; |
| 413 | /* control field */ |
| 414 | if (LAPD_CTRL_is_I(msg->l2h[i])) { |
| 415 | lctx.format = LAPD_FORM_I; |
| 416 | lctx.n_send = LAPD_CTRL_I_Ns(msg->l2h[i]); |
| 417 | i++; |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 418 | if (msg->len < 3 && i == 2) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 419 | LOGLI(li, LOGL_ERROR, "LAPD I frame without TEI " |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 420 | "receive len %d < 3, ignoring\n", msg->len); |
| 421 | *error = LAPD_ERR_BAD_LEN; |
| 422 | return -EINVAL; |
| 423 | }; |
| 424 | if (msg->len < 4 && i == 3) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 425 | LOGLI(li, LOGL_ERROR, "LAPD I frame with TEI " |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 426 | "receive len %d < 4, ignoring\n", msg->len); |
| 427 | *error = LAPD_ERR_BAD_LEN; |
| 428 | return -EINVAL; |
| 429 | }; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 430 | lctx.n_recv = LAPD_CTRL_Nr(msg->l2h[i]); |
| 431 | lctx.p_f = LAPD_CTRL_I_P(msg->l2h[i]); |
| 432 | } else if (LAPD_CTRL_is_S(msg->l2h[i])) { |
| 433 | lctx.format = LAPD_FORM_S; |
| 434 | lctx.s_u = LAPD_CTRL_S_BITS(msg->l2h[i]); |
| 435 | i++; |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 436 | if (msg->len < 3 && i == 2) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 437 | LOGLI(li, LOGL_ERROR, "LAPD S frame without TEI " |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 438 | "receive len %d < 3, ignoring\n", msg->len); |
| 439 | *error = LAPD_ERR_BAD_LEN; |
| 440 | return -EINVAL; |
| 441 | }; |
| 442 | if (msg->len < 4 && i == 3) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 443 | LOGLI(li, LOGL_ERROR, "LAPD S frame with TEI " |
Andreas Eversberg | 8aaed05 | 2011-10-01 04:10:57 +0200 | [diff] [blame] | 444 | "receive len %d < 4, ignoring\n", msg->len); |
| 445 | *error = LAPD_ERR_BAD_LEN; |
| 446 | return -EINVAL; |
| 447 | }; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 448 | lctx.n_recv = LAPD_CTRL_Nr(msg->l2h[i]); |
| 449 | lctx.p_f = LAPD_CTRL_S_PF(msg->l2h[i]); |
| 450 | } else if (LAPD_CTRL_is_U(msg->l2h[i])) { |
| 451 | lctx.format = LAPD_FORM_U; |
| 452 | lctx.s_u = LAPD_CTRL_U_BITS(msg->l2h[i]); |
| 453 | lctx.p_f = LAPD_CTRL_U_PF(msg->l2h[i]); |
| 454 | } else |
| 455 | lctx.format = LAPD_FORM_UKN; |
| 456 | i++; |
| 457 | /* length */ |
| 458 | msg->l3h = msg->l2h + i; |
| 459 | msgb_pull(msg, i); |
| 460 | lctx.length = msg->len; |
| 461 | |
| 462 | /* perform TEI assignment, if received */ |
| 463 | if (lctx.tei == 127) { |
| 464 | rc = lapd_tei_receive(li, msg->data, msg->len); |
| 465 | msgb_free(msg); |
| 466 | return rc; |
| 467 | } |
| 468 | |
| 469 | /* resolve TEI and SAPI */ |
| 470 | teip = teip_from_tei(li, lctx.tei); |
| 471 | if (!teip) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 472 | LOGLI(li, LOGL_NOTICE, "LAPD Unknown TEI %u\n", lctx.tei); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 473 | *error = LAPD_ERR_UNKNOWN_TEI; |
| 474 | msgb_free(msg); |
| 475 | return -EINVAL; |
| 476 | } |
| 477 | sap = lapd_sap_find(teip, lctx.sapi); |
| 478 | if (!sap) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 479 | LOGTEI(teip, LOGL_INFO, "LAPD No SAP for TEI=%u / SAPI=%u, " |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 480 | "allocating\n", lctx.tei, lctx.sapi); |
| 481 | sap = lapd_sap_alloc(teip, lctx.sapi); |
| 482 | if (!sap) { |
| 483 | *error = LAPD_ERR_NO_MEM; |
| 484 | msgb_free(msg); |
| 485 | return -ENOMEM; |
| 486 | } |
| 487 | } |
| 488 | lctx.dl = &sap->dl; |
| 489 | lctx.n201 = lctx.dl->maxf; |
| 490 | |
| 491 | if (msg->len > lctx.n201) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 492 | LOGSAP(sap, LOGL_ERROR, "message len %d > N201(%d) " |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 493 | "(discarding)\n", msg->len, lctx.n201); |
| 494 | msgb_free(msg); |
| 495 | *error = LAPD_ERR_BAD_LEN; |
| 496 | return -EINVAL; |
| 497 | } |
| 498 | |
| 499 | /* send to LAPD */ |
| 500 | return lapd_ph_data_ind(msg, &lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 501 | } |
| 502 | |
| 503 | /* Start a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */ |
| 504 | int lapd_sap_start(struct lapd_instance *li, uint8_t tei, uint8_t sapi) |
| 505 | { |
| 506 | struct lapd_sap *sap; |
| 507 | struct lapd_tei *teip; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 508 | struct osmo_dlsap_prim dp; |
| 509 | struct msgb *msg; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 510 | |
| 511 | teip = teip_from_tei(li, tei); |
| 512 | if (!teip) |
| 513 | teip = lapd_tei_alloc(li, tei); |
| 514 | |
| 515 | sap = lapd_sap_find(teip, sapi); |
| 516 | if (sap) |
| 517 | return -EEXIST; |
| 518 | |
| 519 | sap = lapd_sap_alloc(teip, sapi); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 520 | if (!sap) |
| 521 | return -ENOMEM; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 522 | |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 523 | LOGSAP(sap, LOGL_NOTICE, "LAPD DL-ESTABLISH request TEI=%d SAPI=%d\n", tei, sapi); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 524 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 525 | /* prepare prim */ |
Harald Welte | ea7da44 | 2020-07-03 19:05:07 +0200 | [diff] [blame] | 526 | msg = msgb_alloc_headroom(DLSAP_MSGB_SIZE, DLSAP_MSGB_HEADROOM, "DL EST"); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 527 | msg->l3h = msg->data; |
| 528 | osmo_prim_init(&dp.oph, 0, PRIM_DL_EST, PRIM_OP_REQUEST, msg); |
| 529 | |
| 530 | /* send to L2 */ |
| 531 | return lapd_recv_dlsap(&dp, &sap->dl.lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 532 | } |
| 533 | |
| 534 | /* Stop a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */ |
| 535 | int lapd_sap_stop(struct lapd_instance *li, uint8_t tei, uint8_t sapi) |
| 536 | { |
| 537 | struct lapd_tei *teip; |
| 538 | struct lapd_sap *sap; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 539 | struct osmo_dlsap_prim dp; |
| 540 | struct msgb *msg; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 541 | |
| 542 | teip = teip_from_tei(li, tei); |
| 543 | if (!teip) |
| 544 | return -ENODEV; |
| 545 | |
| 546 | sap = lapd_sap_find(teip, sapi); |
| 547 | if (!sap) |
| 548 | return -ENODEV; |
| 549 | |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 550 | LOGSAP(sap, LOGL_NOTICE, "LAPD DL-RELEASE request TEI=%d SAPI=%d\n", tei, sapi); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 551 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 552 | /* prepare prim */ |
Harald Welte | ea7da44 | 2020-07-03 19:05:07 +0200 | [diff] [blame] | 553 | msg = msgb_alloc_headroom(DLSAP_MSGB_SIZE, DLSAP_MSGB_HEADROOM, "DL REL"); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 554 | msg->l3h = msg->data; |
| 555 | osmo_prim_init(&dp.oph, 0, PRIM_DL_REL, PRIM_OP_REQUEST, msg); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 556 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 557 | /* send to L2 */ |
| 558 | return lapd_recv_dlsap(&dp, &sap->dl.lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 559 | } |
| 560 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 561 | /* Transmit Data (DL-DATA request) on the given LAPD Instance / TEI / SAPI */ |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 562 | void lapd_transmit(struct lapd_instance *li, uint8_t tei, uint8_t sapi, |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 563 | struct msgb *msg) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 564 | { |
| 565 | struct lapd_tei *teip = teip_from_tei(li, tei); |
| 566 | struct lapd_sap *sap; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 567 | struct osmo_dlsap_prim dp; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 568 | |
| 569 | if (!teip) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 570 | LOGLI(li, LOGL_ERROR, "LAPD Cannot transmit on non-existing TEI %u\n", tei); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 571 | msgb_free(msg); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 572 | return; |
| 573 | } |
| 574 | |
| 575 | sap = lapd_sap_find(teip, sapi); |
| 576 | if (!sap) { |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 577 | LOGTEI(teip, LOGL_INFO, "LAPD Tx on unknown SAPI=%u in TEI=%u\n", sapi, tei); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 578 | msgb_free(msg); |
| 579 | return; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 580 | } |
| 581 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 582 | /* prepare prim */ |
| 583 | msg->l3h = msg->data; |
| 584 | osmo_prim_init(&dp.oph, 0, PRIM_DL_DATA, PRIM_OP_REQUEST, msg); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 585 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 586 | /* send to L2 */ |
| 587 | lapd_recv_dlsap(&dp, &sap->dl.lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 588 | }; |
| 589 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 590 | static int send_ph_data_req(struct lapd_msg_ctx *lctx, struct msgb *msg) |
| 591 | { |
| 592 | struct lapd_datalink *dl = lctx->dl; |
| 593 | struct lapd_sap *sap = |
| 594 | container_of(dl, struct lapd_sap, dl); |
| 595 | struct lapd_instance *li = sap->tei->li; |
| 596 | int format = lctx->format; |
| 597 | int addr_len; |
| 598 | |
| 599 | /* control field */ |
| 600 | switch (format) { |
| 601 | case LAPD_FORM_I: |
| 602 | msg->l2h = msgb_push(msg, 2); |
| 603 | msg->l2h[0] = LAPD_CTRL_I4(lctx->n_send); |
| 604 | msg->l2h[1] = LAPD_CTRL_I5(lctx->n_recv, lctx->p_f); |
| 605 | break; |
| 606 | case LAPD_FORM_S: |
| 607 | msg->l2h = msgb_push(msg, 2); |
| 608 | msg->l2h[0] = LAPD_CTRL_S4(lctx->s_u); |
| 609 | msg->l2h[1] = LAPD_CTRL_S5(lctx->n_recv, lctx->p_f); |
| 610 | break; |
| 611 | case LAPD_FORM_U: |
| 612 | msg->l2h = msgb_push(msg, 1); |
| 613 | msg->l2h[0] = LAPD_CTRL_U4(lctx->s_u, lctx->p_f); |
| 614 | break; |
| 615 | default: |
| 616 | msgb_free(msg); |
| 617 | return -EINVAL; |
| 618 | } |
| 619 | /* address field */ |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 620 | if (li->profile.short_address && lctx->tei == 0) |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 621 | addr_len = 1; |
| 622 | else |
| 623 | addr_len = 2; |
| 624 | msg->l2h = msgb_push(msg, addr_len); |
| 625 | msg->l2h[0] = LAPD_ADDR2(lctx->sapi, lctx->cr); |
| 626 | if (addr_len == 1) |
| 627 | msg->l2h[0] |= 0x1; |
| 628 | else |
| 629 | msg->l2h[1] = LAPD_ADDR3(lctx->tei); |
| 630 | |
Pablo Neira Ayuso | 9530600 | 2012-08-22 16:43:59 +0200 | [diff] [blame] | 631 | /* write to PCAP file, if enabled. */ |
| 632 | osmo_pcap_lapd_write(li->pcap_fd, OSMO_LAPD_PCAP_OUTPUT, msg); |
| 633 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 634 | /* forward frame to L1 */ |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 635 | LOGDL(dl, LOGL_DEBUG, "TX: %s\n", osmo_hexdump(msg->data, msg->len)); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 636 | li->transmit_cb(msg, li->transmit_cbdata); |
| 637 | |
| 638 | return 0; |
| 639 | } |
| 640 | |
| 641 | /* A DL-SAP message is received from datalink instance and forwarded to L3 */ |
| 642 | static int send_dlsap(struct osmo_dlsap_prim *dp, struct lapd_msg_ctx *lctx) |
| 643 | { |
| 644 | struct lapd_datalink *dl = lctx->dl; |
| 645 | struct lapd_sap *sap = |
| 646 | container_of(dl, struct lapd_sap, dl); |
| 647 | struct lapd_instance *li; |
| 648 | uint8_t tei, sapi; |
Pau Espin Pedrol | 6ffeb9a | 2020-07-15 15:27:16 +0200 | [diff] [blame] | 649 | char *op = (dp->oph.operation == PRIM_OP_INDICATION) ? "indication" |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 650 | : "confirm"; |
| 651 | |
| 652 | li = sap->tei->li; |
| 653 | tei = lctx->tei; |
| 654 | sapi = lctx->sapi; |
| 655 | |
| 656 | switch (dp->oph.primitive) { |
| 657 | case PRIM_DL_EST: |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 658 | LOGDL(dl, LOGL_NOTICE, "LAPD DL-ESTABLISH %s TEI=%d " |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 659 | "SAPI=%d\n", op, lctx->tei, lctx->sapi); |
| 660 | break; |
| 661 | case PRIM_DL_REL: |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 662 | LOGDL(dl, LOGL_NOTICE, "LAPD DL-RELEASE %s TEI=%d " |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 663 | "SAPI=%d\n", op, lctx->tei, lctx->sapi); |
| 664 | lapd_sap_free(sap); |
| 665 | /* note: sap and dl is now gone, don't use it anymore */ |
| 666 | break; |
| 667 | default: |
| 668 | ; |
| 669 | } |
| 670 | |
| 671 | li->receive_cb(dp, tei, sapi, li->receive_cbdata); |
| 672 | |
| 673 | return 0; |
| 674 | } |
| 675 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 676 | /* Allocate a new LAPD instance */ |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 677 | struct lapd_instance *lapd_instance_alloc2(int network_side, |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 678 | void (*tx_cb)(struct msgb *msg, void *cbdata), void *tx_cbdata, |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 679 | void (*rx_cb)(struct osmo_dlsap_prim *odp, uint8_t tei, uint8_t sapi, |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 680 | void *rx_cbdata), void *rx_cbdata, |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 681 | const struct lapd_profile *profile, const char *name) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 682 | { |
| 683 | struct lapd_instance *li; |
| 684 | |
| 685 | li = talloc_zero(NULL, struct lapd_instance); |
| 686 | if (!li) |
| 687 | return NULL; |
| 688 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 689 | li->network_side = network_side; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 690 | li->transmit_cb = tx_cb; |
| 691 | li->transmit_cbdata = tx_cbdata; |
| 692 | li->receive_cb = rx_cb; |
| 693 | li->receive_cbdata = rx_cbdata; |
Pablo Neira Ayuso | 9530600 | 2012-08-22 16:43:59 +0200 | [diff] [blame] | 694 | li->pcap_fd = -1; |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 695 | li->name = talloc_strdup(li, name); |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 696 | memcpy(&li->profile, profile, sizeof(li->profile)); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 697 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 698 | INIT_LLIST_HEAD(&li->tei_list); |
| 699 | |
| 700 | return li; |
| 701 | } |
Harald Welte | 14078ea | 2011-08-24 09:45:11 +0200 | [diff] [blame] | 702 | |
Harald Welte | b903188 | 2020-05-02 21:09:15 +0200 | [diff] [blame] | 703 | struct lapd_instance *lapd_instance_alloc(int network_side, |
| 704 | void (*tx_cb)(struct msgb *msg, void *cbdata), void *tx_cbdata, |
| 705 | void (*rx_cb)(struct osmo_dlsap_prim *odp, uint8_t tei, uint8_t sapi, |
| 706 | void *rx_cbdata), void *rx_cbdata, |
| 707 | const struct lapd_profile *profile) |
| 708 | { |
| 709 | return lapd_instance_alloc2(network_side, tx_cbdata, tx_cb, rx_cb, rx_cbdata, profile, NULL); |
| 710 | } |
| 711 | |
| 712 | |
Philipp | 0c7d5f4 | 2016-10-19 18:38:58 +0200 | [diff] [blame] | 713 | /* Change lapd-profile on the fly (use with caution!) */ |
| 714 | void lapd_instance_set_profile(struct lapd_instance *li, |
| 715 | const struct lapd_profile *profile) |
| 716 | { |
| 717 | memcpy(&li->profile, profile, sizeof(li->profile)); |
| 718 | } |
| 719 | |
Harald Welte | 14078ea | 2011-08-24 09:45:11 +0200 | [diff] [blame] | 720 | void lapd_instance_free(struct lapd_instance *li) |
| 721 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 722 | struct lapd_tei *teip, *teip2; |
Harald Welte | f350e25 | 2011-08-26 07:55:26 +0200 | [diff] [blame] | 723 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 724 | /* Free all TEI instances */ |
| 725 | llist_for_each_entry_safe(teip, teip2, &li->tei_list, list) { |
| 726 | lapd_tei_free(teip); |
Harald Welte | f350e25 | 2011-08-26 07:55:26 +0200 | [diff] [blame] | 727 | } |
| 728 | |
Harald Welte | 14078ea | 2011-08-24 09:45:11 +0200 | [diff] [blame] | 729 | talloc_free(li); |
| 730 | } |