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 | * |
| 11 | * This program is free software; you can redistribute it and/or modify |
| 12 | * it under the terms of the GNU General Public License as published by |
| 13 | * the Free Software Foundation; either version 2 of the License, or |
| 14 | * (at your option) any later version. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License along |
| 22 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 23 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 24 | * |
| 25 | */ |
| 26 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 27 | #include "internal.h" |
| 28 | |
| 29 | #include <stdio.h> |
| 30 | #include <string.h> |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 31 | #include <errno.h> |
| 32 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 33 | #include <osmocom/core/linuxlist.h> |
| 34 | #include <osmocom/core/logging.h> |
Harald Welte | 71d87b2 | 2011-07-18 14:49:56 +0200 | [diff] [blame] | 35 | #include <osmocom/core/talloc.h> |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 36 | #include <osmocom/core/msgb.h> |
| 37 | #include <osmocom/core/timer.h> |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 38 | #include <osmocom/abis/lapd.h> |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 39 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 40 | #define LAPD_ADDR2(sapi, cr) ((((sapi) & 0x3f) << 2) | (((cr) & 0x1) << 1)) |
| 41 | #define LAPD_ADDR3(tei) ((((tei) & 0x7f) << 1) | 0x1) |
| 42 | |
| 43 | #define LAPD_ADDR_SAPI(addr) ((addr) >> 2) |
| 44 | #define LAPD_ADDR_CR(addr) (((addr) >> 1) & 0x1) |
| 45 | #define LAPD_ADDR_EA(addr) ((addr) & 0x1) |
| 46 | #define LAPD_ADDR_TEI(addr) ((addr) >> 1) |
| 47 | |
| 48 | #define LAPD_CTRL_I4(ns) (((ns) & 0x7f) << 1) |
| 49 | #define LAPD_CTRL_I5(nr, p) ((((nr) & 0x7f) << 1) | ((p) & 0x1)) |
| 50 | #define LAPD_CTRL_S4(s) ((((s) & 0x3) << 2) | 0x1) |
| 51 | #define LAPD_CTRL_S5(nr, p) ((((nr) & 0x7f) << 1) | ((p) & 0x1)) |
| 52 | #define LAPD_CTRL_U4(u, p) ((((u) & 0x1c) << (5-2)) | (((p) & 0x1) << 4) | (((u) & 0x3) << 2) | 0x3) |
| 53 | |
| 54 | #define LAPD_CTRL_is_I(ctrl) (((ctrl) & 0x1) == 0) |
| 55 | #define LAPD_CTRL_is_S(ctrl) (((ctrl) & 0x3) == 1) |
| 56 | #define LAPD_CTRL_is_U(ctrl) (((ctrl) & 0x3) == 3) |
| 57 | |
| 58 | #define LAPD_CTRL_U_BITS(ctrl) ((((ctrl) & 0xC) >> 2) | ((ctrl) & 0xE0) >> 3) |
| 59 | #define LAPD_CTRL_U_PF(ctrl) (((ctrl) >> 4) & 0x1) |
| 60 | |
| 61 | #define LAPD_CTRL_S_BITS(ctrl) (((ctrl) & 0xC) >> 2) |
| 62 | #define LAPD_CTRL_S_PF(ctrl) (ctrl & 0x1) |
| 63 | |
| 64 | #define LAPD_CTRL_I_Ns(ctrl) (((ctrl) & 0xFE) >> 1) |
| 65 | #define LAPD_CTRL_I_P(ctrl) (ctrl & 0x1) |
| 66 | #define LAPD_CTRL_Nr(ctrl) (((ctrl) & 0xFE) >> 1) |
| 67 | |
| 68 | #define LAPD_LEN(len) ((len << 2) | 0x1) |
| 69 | #define LAPD_EL 0x1 |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 70 | |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 71 | #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} |
| 72 | |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 73 | const struct lapd_profile lapd_profile_isdn = { |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 74 | LAPD_SET_K(7,7), |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 75 | 3, |
| 76 | 260, |
| 77 | 3, |
| 78 | 1,0, |
| 79 | 1,0, |
| 80 | 10,0, |
| 81 | 0 |
| 82 | }; |
| 83 | |
| 84 | const struct lapd_profile lapd_profile_abis = { |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 85 | LAPD_SET_K(2,1), |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 86 | 3, |
| 87 | 260, |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 88 | 0, /* infinite */ |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 89 | 0,240000, |
| 90 | 1,0, |
| 91 | 10,0, |
| 92 | 0 |
| 93 | }; |
| 94 | |
| 95 | const struct lapd_profile lapd_profile_sat = { |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 96 | LAPD_SET_K(15,15), |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 97 | 5, |
| 98 | 260, |
| 99 | 5, |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 100 | 2,400000, |
| 101 | 2,400000, |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 102 | 20,0, |
| 103 | 1 |
| 104 | }; |
| 105 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 106 | typedef enum { |
| 107 | LAPD_TEI_NONE = 0, |
| 108 | LAPD_TEI_ASSIGNED, |
| 109 | LAPD_TEI_ACTIVE, |
| 110 | } lapd_tei_state; |
| 111 | |
| 112 | const char *lapd_tei_states[] = { |
| 113 | "NONE", |
| 114 | "ASSIGNED", |
| 115 | "ACTIVE", |
| 116 | }; |
| 117 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 118 | /* Structure representing an allocated TEI within a LAPD instance. */ |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 119 | struct lapd_tei { |
| 120 | struct llist_head list; |
| 121 | struct lapd_instance *li; |
| 122 | uint8_t tei; |
| 123 | lapd_tei_state state; |
| 124 | |
| 125 | struct llist_head sap_list; |
| 126 | }; |
| 127 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 128 | /* Structure representing a SAP within a TEI. It includes exactly one datalink |
| 129 | * instance. */ |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 130 | struct lapd_sap { |
| 131 | struct llist_head list; |
| 132 | struct lapd_tei *tei; |
| 133 | uint8_t sapi; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 134 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 135 | struct lapd_datalink dl; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 136 | }; |
| 137 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 138 | /* Resolve TEI structure from given numeric TEI */ |
| 139 | static struct lapd_tei *teip_from_tei(struct lapd_instance *li, uint8_t tei) |
| 140 | { |
| 141 | struct lapd_tei *lt; |
| 142 | |
| 143 | llist_for_each_entry(lt, &li->tei_list, list) { |
| 144 | if (lt->tei == tei) |
| 145 | return lt; |
| 146 | } |
| 147 | return NULL; |
| 148 | }; |
| 149 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 150 | /* Change state of TEI */ |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 151 | static void lapd_tei_set_state(struct lapd_tei *teip, int newstate) |
| 152 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 153 | LOGP(DLLAPD, LOGL_INFO, "LAPD state change on TEI %d: %s -> %s\n", |
| 154 | teip->tei, lapd_tei_states[teip->state], |
| 155 | lapd_tei_states[newstate]); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 156 | teip->state = newstate; |
| 157 | }; |
| 158 | |
| 159 | /* Allocate a new TEI */ |
| 160 | struct lapd_tei *lapd_tei_alloc(struct lapd_instance *li, uint8_t tei) |
| 161 | { |
| 162 | struct lapd_tei *teip; |
| 163 | |
| 164 | teip = talloc_zero(li, struct lapd_tei); |
| 165 | if (!teip) |
| 166 | return NULL; |
| 167 | |
| 168 | teip->li = li; |
| 169 | teip->tei = tei; |
| 170 | llist_add(&teip->list, &li->tei_list); |
| 171 | INIT_LLIST_HEAD(&teip->sap_list); |
| 172 | |
| 173 | lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED); |
| 174 | |
| 175 | return teip; |
| 176 | } |
| 177 | |
| 178 | /* Find a SAP within a given TEI */ |
| 179 | static struct lapd_sap *lapd_sap_find(struct lapd_tei *teip, uint8_t sapi) |
| 180 | { |
| 181 | struct lapd_sap *sap; |
| 182 | |
| 183 | llist_for_each_entry(sap, &teip->sap_list, list) { |
| 184 | if (sap->sapi == sapi) |
| 185 | return sap; |
| 186 | } |
| 187 | |
| 188 | return NULL; |
| 189 | } |
| 190 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 191 | static int send_ph_data_req(struct lapd_msg_ctx *lctx, struct msgb *msg); |
| 192 | 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] | 193 | |
| 194 | /* Allocate a new SAP within a given TEI */ |
| 195 | static struct lapd_sap *lapd_sap_alloc(struct lapd_tei *teip, uint8_t sapi) |
| 196 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 197 | struct lapd_sap *sap; |
| 198 | struct lapd_datalink *dl; |
| 199 | struct lapd_instance *li; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 200 | struct lapd_profile *profile; |
| 201 | int k; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 202 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 203 | sap = talloc_zero(teip, struct lapd_sap); |
| 204 | if (!sap) |
| 205 | return NULL; |
| 206 | |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 207 | LOGP(DLLAPD, LOGL_NOTICE, "LAPD Allocating SAP for SAPI=%u / TEI=%u\n", |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 208 | sapi, teip->tei); |
| 209 | |
| 210 | sap->sapi = sapi; |
| 211 | sap->tei = teip; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 212 | dl = &sap->dl; |
| 213 | li = teip->li; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 214 | profile = &li->profile; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 215 | |
Andreas Eversberg | 3c46044 | 2011-09-28 02:46:16 +0200 | [diff] [blame^] | 216 | k = profile->k[sapi & 0x3f]; |
| 217 | LOGP(DLLAPD, LOGL_NOTICE, "k=%d N200=%d N201=%d T200=%d.%d T203=%d.%d" |
| 218 | "\n", k, profile->n200, profile->n201, profile->t200_sec, |
| 219 | profile->t200_usec, profile->t203_sec, profile->t203_usec); |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 220 | lapd_dl_init(dl, k, 128, profile->n201); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 221 | dl->use_sabme = 1; /* use SABME instead of SABM (GSM) */ |
| 222 | dl->send_ph_data_req = send_ph_data_req; |
| 223 | dl->send_dlsap = send_dlsap; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 224 | dl->n200 = profile->n200; |
| 225 | dl->n200_est_rel = profile->n200; |
| 226 | dl->t200_sec = profile->t200_sec; dl->t200_usec = profile->t200_usec; |
| 227 | dl->t203_sec = profile->t203_sec; dl->t203_usec = profile->t203_usec; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 228 | dl->lctx.dl = &sap->dl; |
| 229 | dl->lctx.sapi = sapi; |
| 230 | dl->lctx.tei = teip->tei; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 231 | dl->lctx.n201 = profile->n201; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 232 | |
| 233 | lapd_set_mode(&sap->dl, (teip->li->network_side) ? LAPD_MODE_NETWORK |
| 234 | : LAPD_MODE_USER); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 235 | |
| 236 | llist_add(&sap->list, &teip->sap_list); |
| 237 | |
| 238 | return sap; |
| 239 | } |
| 240 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 241 | /* Free SAP instance, including the datalink */ |
| 242 | static void lapd_sap_free(struct lapd_sap *sap) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 243 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 244 | /* free datalink structures and timers */ |
| 245 | lapd_dl_exit(&sap->dl); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 246 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 247 | llist_del(&sap->list); |
| 248 | talloc_free(sap); |
| 249 | } |
| 250 | |
| 251 | /* Free TEI instance */ |
| 252 | static void lapd_tei_free(struct lapd_tei *teip) |
| 253 | { |
| 254 | struct lapd_sap *sap, *sap2; |
| 255 | |
| 256 | llist_for_each_entry_safe(sap, sap2, &teip->sap_list, list) { |
| 257 | lapd_sap_free(sap); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 258 | } |
| 259 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 260 | llist_del(&teip->list); |
| 261 | talloc_free(teip); |
| 262 | } |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 263 | |
| 264 | /* Input function into TEI manager */ |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 265 | 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] | 266 | { |
| 267 | uint8_t entity = data[0]; |
| 268 | uint8_t ref = data[1]; |
| 269 | uint8_t mt = data[3]; |
| 270 | uint8_t action = data[4] >> 1; |
| 271 | uint8_t e = data[4] & 1; |
| 272 | uint8_t resp[8]; |
| 273 | struct lapd_tei *teip; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 274 | struct msgb *msg; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 275 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 276 | DEBUGP(DLLAPD, "LAPD TEIMGR: entity %x, ref %x, mt %x, action %x, " |
| 277 | "e %x\n", entity, ref, mt, action, e); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 278 | |
| 279 | switch (mt) { |
| 280 | case 0x01: /* IDENTITY REQUEST */ |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 281 | DEBUGP(DLLAPD, "LAPD TEIMGR: identity request for TEI %u\n", |
| 282 | action); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 283 | |
| 284 | teip = teip_from_tei(li, action); |
| 285 | if (!teip) { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 286 | LOGP(DLLAPD, LOGL_INFO, "TEI MGR: New TEI %u\n", |
| 287 | action); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 288 | teip = lapd_tei_alloc(li, action); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 289 | if (!teip) |
| 290 | return -ENOMEM; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 291 | } |
| 292 | |
| 293 | /* Send ACCEPT */ |
| 294 | memmove(resp, "\xfe\xff\x03\x0f\x00\x00\x02\x00", 8); |
| 295 | resp[7] = (action << 1) | 1; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 296 | msg = msgb_alloc_headroom(56, 56, "DL EST"); |
| 297 | msg->l2h = msgb_push(msg, 8); |
| 298 | memcpy(msg->l2h, resp, 8); |
| 299 | LOGP(DLLAPD, LOGL_DEBUG, "TX: %s\n", |
| 300 | osmo_hexdump(msg->data, msg->len)); |
| 301 | li->transmit_cb(msg, li->transmit_cbdata); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 302 | |
| 303 | if (teip->state == LAPD_TEI_NONE) |
| 304 | lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED); |
| 305 | break; |
| 306 | default: |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 307 | LOGP(DLLAPD, LOGL_NOTICE, "LAPD TEIMGR: unknown mt %x " |
| 308 | "action %x\n", mt, action); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 309 | break; |
| 310 | }; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 311 | |
| 312 | return 0; |
| 313 | } |
| 314 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 315 | /* General input function for any data received for this LAPD instance */ |
| 316 | 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] | 317 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 318 | int i; |
| 319 | struct lapd_msg_ctx lctx; |
| 320 | int rc; |
| 321 | struct lapd_sap *sap; |
| 322 | struct lapd_tei *teip; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 323 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 324 | LOGP(DLLAPD, LOGL_DEBUG, "RX: %s\n", osmo_hexdump(msg->data, msg->len)); |
| 325 | if (msg->len < 2) { |
| 326 | LOGP(DLLAPD, LOGL_ERROR, "LAPD receive len %d < 2, ignoring\n", |
| 327 | msg->len); |
| 328 | *error = LAPD_ERR_BAD_LEN; |
| 329 | return -EINVAL; |
| 330 | }; |
| 331 | msg->l2h = msg->data; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 332 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 333 | memset(&lctx, 0, sizeof(lctx)); |
| 334 | |
| 335 | i = 0; |
| 336 | /* adress field */ |
| 337 | lctx.sapi = LAPD_ADDR_SAPI(msg->l2h[i]); |
| 338 | lctx.cr = LAPD_ADDR_CR(msg->l2h[i]); |
| 339 | lctx.lpd = 0; |
| 340 | if (!LAPD_ADDR_EA(msg->l2h[i])) { |
| 341 | i++; |
| 342 | lctx.tei = LAPD_ADDR_TEI(msg->l2h[i]); |
| 343 | } |
| 344 | i++; |
| 345 | /* control field */ |
| 346 | if (LAPD_CTRL_is_I(msg->l2h[i])) { |
| 347 | lctx.format = LAPD_FORM_I; |
| 348 | lctx.n_send = LAPD_CTRL_I_Ns(msg->l2h[i]); |
| 349 | i++; |
| 350 | lctx.n_recv = LAPD_CTRL_Nr(msg->l2h[i]); |
| 351 | lctx.p_f = LAPD_CTRL_I_P(msg->l2h[i]); |
| 352 | } else if (LAPD_CTRL_is_S(msg->l2h[i])) { |
| 353 | lctx.format = LAPD_FORM_S; |
| 354 | lctx.s_u = LAPD_CTRL_S_BITS(msg->l2h[i]); |
| 355 | i++; |
| 356 | lctx.n_recv = LAPD_CTRL_Nr(msg->l2h[i]); |
| 357 | lctx.p_f = LAPD_CTRL_S_PF(msg->l2h[i]); |
| 358 | } else if (LAPD_CTRL_is_U(msg->l2h[i])) { |
| 359 | lctx.format = LAPD_FORM_U; |
| 360 | lctx.s_u = LAPD_CTRL_U_BITS(msg->l2h[i]); |
| 361 | lctx.p_f = LAPD_CTRL_U_PF(msg->l2h[i]); |
| 362 | } else |
| 363 | lctx.format = LAPD_FORM_UKN; |
| 364 | i++; |
| 365 | /* length */ |
| 366 | msg->l3h = msg->l2h + i; |
| 367 | msgb_pull(msg, i); |
| 368 | lctx.length = msg->len; |
| 369 | |
| 370 | /* perform TEI assignment, if received */ |
| 371 | if (lctx.tei == 127) { |
| 372 | rc = lapd_tei_receive(li, msg->data, msg->len); |
| 373 | msgb_free(msg); |
| 374 | return rc; |
| 375 | } |
| 376 | |
| 377 | /* resolve TEI and SAPI */ |
| 378 | teip = teip_from_tei(li, lctx.tei); |
| 379 | if (!teip) { |
| 380 | LOGP(DLLAPD, LOGL_NOTICE, "LAPD Unknown TEI %u\n", lctx.tei); |
| 381 | *error = LAPD_ERR_UNKNOWN_TEI; |
| 382 | msgb_free(msg); |
| 383 | return -EINVAL; |
| 384 | } |
| 385 | sap = lapd_sap_find(teip, lctx.sapi); |
| 386 | if (!sap) { |
| 387 | LOGP(DLLAPD, LOGL_INFO, "LAPD No SAP for TEI=%u / SAPI=%u, " |
| 388 | "allocating\n", lctx.tei, lctx.sapi); |
| 389 | sap = lapd_sap_alloc(teip, lctx.sapi); |
| 390 | if (!sap) { |
| 391 | *error = LAPD_ERR_NO_MEM; |
| 392 | msgb_free(msg); |
| 393 | return -ENOMEM; |
| 394 | } |
| 395 | } |
| 396 | lctx.dl = &sap->dl; |
| 397 | lctx.n201 = lctx.dl->maxf; |
| 398 | |
| 399 | if (msg->len > lctx.n201) { |
| 400 | LOGP(DLLAPD, LOGL_ERROR, "message len %d > N201(%d) " |
| 401 | "(discarding)\n", msg->len, lctx.n201); |
| 402 | msgb_free(msg); |
| 403 | *error = LAPD_ERR_BAD_LEN; |
| 404 | return -EINVAL; |
| 405 | } |
| 406 | |
| 407 | /* send to LAPD */ |
| 408 | return lapd_ph_data_ind(msg, &lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 409 | } |
| 410 | |
| 411 | /* Start a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */ |
| 412 | int lapd_sap_start(struct lapd_instance *li, uint8_t tei, uint8_t sapi) |
| 413 | { |
| 414 | struct lapd_sap *sap; |
| 415 | struct lapd_tei *teip; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 416 | struct osmo_dlsap_prim dp; |
| 417 | struct msgb *msg; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 418 | |
| 419 | teip = teip_from_tei(li, tei); |
| 420 | if (!teip) |
| 421 | teip = lapd_tei_alloc(li, tei); |
| 422 | |
| 423 | sap = lapd_sap_find(teip, sapi); |
| 424 | if (sap) |
| 425 | return -EEXIST; |
| 426 | |
| 427 | sap = lapd_sap_alloc(teip, sapi); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 428 | if (!sap) |
| 429 | return -ENOMEM; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 430 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 431 | LOGP(DLLAPD, LOGL_NOTICE, "LAPD DL-ESTABLISH request TEI=%d SAPI=%d\n", |
| 432 | tei, sapi); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 433 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 434 | /* prepare prim */ |
| 435 | msg = msgb_alloc_headroom(56, 56, "DL EST"); |
| 436 | msg->l3h = msg->data; |
| 437 | osmo_prim_init(&dp.oph, 0, PRIM_DL_EST, PRIM_OP_REQUEST, msg); |
| 438 | |
| 439 | /* send to L2 */ |
| 440 | return lapd_recv_dlsap(&dp, &sap->dl.lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 441 | } |
| 442 | |
| 443 | /* Stop a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */ |
| 444 | int lapd_sap_stop(struct lapd_instance *li, uint8_t tei, uint8_t sapi) |
| 445 | { |
| 446 | struct lapd_tei *teip; |
| 447 | struct lapd_sap *sap; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 448 | struct osmo_dlsap_prim dp; |
| 449 | struct msgb *msg; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 450 | |
| 451 | teip = teip_from_tei(li, tei); |
| 452 | if (!teip) |
| 453 | return -ENODEV; |
| 454 | |
| 455 | sap = lapd_sap_find(teip, sapi); |
| 456 | if (!sap) |
| 457 | return -ENODEV; |
| 458 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 459 | LOGP(DLLAPD, LOGL_NOTICE, "LAPD DL-RELEASE request TEI=%d SAPI=%d\n", |
| 460 | tei, sapi); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 461 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 462 | /* prepare prim */ |
| 463 | msg = msgb_alloc_headroom(56, 56, "DL REL"); |
| 464 | msg->l3h = msg->data; |
| 465 | 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] | 466 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 467 | /* send to L2 */ |
| 468 | return lapd_recv_dlsap(&dp, &sap->dl.lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 469 | } |
| 470 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 471 | /* 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] | 472 | 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] | 473 | struct msgb *msg) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 474 | { |
| 475 | struct lapd_tei *teip = teip_from_tei(li, tei); |
| 476 | struct lapd_sap *sap; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 477 | struct osmo_dlsap_prim dp; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 478 | |
| 479 | if (!teip) { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 480 | LOGP(DLLAPD, LOGL_ERROR, "LAPD Cannot transmit on " |
Harald Welte | 4ca16c7 | 2011-08-16 14:01:49 +0200 | [diff] [blame] | 481 | "non-existing TEI %u\n", tei); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 482 | msgb_free(msg); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 483 | return; |
| 484 | } |
| 485 | |
| 486 | sap = lapd_sap_find(teip, sapi); |
| 487 | if (!sap) { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 488 | LOGP(DLLAPD, LOGL_INFO, "LAPD Tx on unknown SAPI=%u " |
| 489 | "in TEI=%u\n", sapi, tei); |
| 490 | msgb_free(msg); |
| 491 | return; |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 492 | } |
| 493 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 494 | /* prepare prim */ |
| 495 | msg->l3h = msg->data; |
| 496 | 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] | 497 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 498 | /* send to L2 */ |
| 499 | lapd_recv_dlsap(&dp, &sap->dl.lctx); |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 500 | }; |
| 501 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 502 | static int send_ph_data_req(struct lapd_msg_ctx *lctx, struct msgb *msg) |
| 503 | { |
| 504 | struct lapd_datalink *dl = lctx->dl; |
| 505 | struct lapd_sap *sap = |
| 506 | container_of(dl, struct lapd_sap, dl); |
| 507 | struct lapd_instance *li = sap->tei->li; |
| 508 | int format = lctx->format; |
| 509 | int addr_len; |
| 510 | |
| 511 | /* control field */ |
| 512 | switch (format) { |
| 513 | case LAPD_FORM_I: |
| 514 | msg->l2h = msgb_push(msg, 2); |
| 515 | msg->l2h[0] = LAPD_CTRL_I4(lctx->n_send); |
| 516 | msg->l2h[1] = LAPD_CTRL_I5(lctx->n_recv, lctx->p_f); |
| 517 | break; |
| 518 | case LAPD_FORM_S: |
| 519 | msg->l2h = msgb_push(msg, 2); |
| 520 | msg->l2h[0] = LAPD_CTRL_S4(lctx->s_u); |
| 521 | msg->l2h[1] = LAPD_CTRL_S5(lctx->n_recv, lctx->p_f); |
| 522 | break; |
| 523 | case LAPD_FORM_U: |
| 524 | msg->l2h = msgb_push(msg, 1); |
| 525 | msg->l2h[0] = LAPD_CTRL_U4(lctx->s_u, lctx->p_f); |
| 526 | break; |
| 527 | default: |
| 528 | msgb_free(msg); |
| 529 | return -EINVAL; |
| 530 | } |
| 531 | /* address field */ |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 532 | if (li->profile.short_address && lctx->tei == 0) |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 533 | addr_len = 1; |
| 534 | else |
| 535 | addr_len = 2; |
| 536 | msg->l2h = msgb_push(msg, addr_len); |
| 537 | msg->l2h[0] = LAPD_ADDR2(lctx->sapi, lctx->cr); |
| 538 | if (addr_len == 1) |
| 539 | msg->l2h[0] |= 0x1; |
| 540 | else |
| 541 | msg->l2h[1] = LAPD_ADDR3(lctx->tei); |
| 542 | |
| 543 | /* forward frame to L1 */ |
| 544 | LOGP(DLLAPD, LOGL_DEBUG, "TX: %s\n", osmo_hexdump(msg->data, msg->len)); |
| 545 | li->transmit_cb(msg, li->transmit_cbdata); |
| 546 | |
| 547 | return 0; |
| 548 | } |
| 549 | |
| 550 | /* A DL-SAP message is received from datalink instance and forwarded to L3 */ |
| 551 | static int send_dlsap(struct osmo_dlsap_prim *dp, struct lapd_msg_ctx *lctx) |
| 552 | { |
| 553 | struct lapd_datalink *dl = lctx->dl; |
| 554 | struct lapd_sap *sap = |
| 555 | container_of(dl, struct lapd_sap, dl); |
| 556 | struct lapd_instance *li; |
| 557 | uint8_t tei, sapi; |
| 558 | char *op = (dp->oph.operation == PRIM_OP_INDICATION) ? "indication" |
| 559 | : "confirm"; |
| 560 | |
| 561 | li = sap->tei->li; |
| 562 | tei = lctx->tei; |
| 563 | sapi = lctx->sapi; |
| 564 | |
| 565 | switch (dp->oph.primitive) { |
| 566 | case PRIM_DL_EST: |
| 567 | LOGP(DLLAPD, LOGL_NOTICE, "LAPD DL-ESTABLISH %s TEI=%d " |
| 568 | "SAPI=%d\n", op, lctx->tei, lctx->sapi); |
| 569 | break; |
| 570 | case PRIM_DL_REL: |
| 571 | LOGP(DLLAPD, LOGL_NOTICE, "LAPD DL-RELEASE %s TEI=%d " |
| 572 | "SAPI=%d\n", op, lctx->tei, lctx->sapi); |
| 573 | lapd_sap_free(sap); |
| 574 | /* note: sap and dl is now gone, don't use it anymore */ |
| 575 | break; |
| 576 | default: |
| 577 | ; |
| 578 | } |
| 579 | |
| 580 | li->receive_cb(dp, tei, sapi, li->receive_cbdata); |
| 581 | |
| 582 | return 0; |
| 583 | } |
| 584 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 585 | /* Allocate a new LAPD instance */ |
| 586 | struct lapd_instance *lapd_instance_alloc(int network_side, |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 587 | void (*tx_cb)(struct msgb *msg, void *cbdata), void *tx_cbdata, |
| 588 | void (*rx_cb)(struct osmo_dlsap_prim *odp, uint8_t tei, uint8_t sapi, |
| 589 | void *rx_cbdata), void *rx_cbdata, |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 590 | const struct lapd_profile *profile) |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 591 | { |
| 592 | struct lapd_instance *li; |
| 593 | |
| 594 | li = talloc_zero(NULL, struct lapd_instance); |
| 595 | if (!li) |
| 596 | return NULL; |
| 597 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 598 | li->network_side = network_side; |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 599 | li->transmit_cb = tx_cb; |
| 600 | li->transmit_cbdata = tx_cbdata; |
| 601 | li->receive_cb = rx_cb; |
| 602 | li->receive_cbdata = rx_cbdata; |
Andreas Eversberg | 3744b87 | 2011-09-27 12:12:36 +0200 | [diff] [blame] | 603 | memcpy(&li->profile, profile, sizeof(li->profile)); |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 604 | |
Pablo Neira Ayuso | 0ba77d5 | 2011-06-05 18:32:44 +0200 | [diff] [blame] | 605 | INIT_LLIST_HEAD(&li->tei_list); |
| 606 | |
| 607 | return li; |
| 608 | } |
Harald Welte | 14078ea | 2011-08-24 09:45:11 +0200 | [diff] [blame] | 609 | |
| 610 | void lapd_instance_free(struct lapd_instance *li) |
| 611 | { |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 612 | struct lapd_tei *teip, *teip2; |
Harald Welte | f350e25 | 2011-08-26 07:55:26 +0200 | [diff] [blame] | 613 | |
Andreas Eversberg | a7ff001 | 2011-09-26 11:29:30 +0200 | [diff] [blame] | 614 | /* Free all TEI instances */ |
| 615 | llist_for_each_entry_safe(teip, teip2, &li->tei_list, list) { |
| 616 | lapd_tei_free(teip); |
Harald Welte | f350e25 | 2011-08-26 07:55:26 +0200 | [diff] [blame] | 617 | } |
| 618 | |
Harald Welte | 14078ea | 2011-08-24 09:45:11 +0200 | [diff] [blame] | 619 | talloc_free(li); |
| 620 | } |