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-rw-r--r--openbsc/src/libabis/input/lapd.c730
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diff --git a/openbsc/src/libabis/input/lapd.c b/openbsc/src/libabis/input/lapd.c
deleted file mode 100644
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--- a/openbsc/src/libabis/input/lapd.c
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@@ -1,730 +0,0 @@
-/* OpenBSC minimal LAPD implementation */
-
-/* (C) 2009 by oystein@homelien.no
- * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
- * (C) 2010 by Digium and Matthew Fredrickson <creslin@digium.com>
- * (C) 2011 by Harald Welte <laforge@gnumonks.org>
- *
- * All Rights Reserved
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- */
-
-/* TODO:
- * detect RR timeout and set SAP state back to SABM_RETRANSMIT
- * use of value_string
- * further code cleanup (spaghetti)
- */
-
-#include <stdio.h>
-#include <string.h>
-#include <errno.h>
-
-#include "lapd.h"
-
-#include <osmocom/core/linuxlist.h>
-#include <osmocom/core/talloc.h>
-#include <osmocom/core/msgb.h>
-#include <osmocom/core/timer.h>
-#include <openbsc/debug.h>
-
-#define SABM_INTERVAL 0, 300000
-
-typedef enum {
- LAPD_TEI_NONE = 0,
- LAPD_TEI_ASSIGNED,
- LAPD_TEI_ACTIVE,
-} lapd_tei_state;
-
-const char *lapd_tei_states[] = {
- "NONE",
- "ASSIGNED",
- "ACTIVE",
-};
-
-typedef enum {
- LAPD_TYPE_NONE = 0,
-
- LAPD_TYPE_I,
- LAPD_TYPE_S,
- LAPD_TYPE_U,
-} lapd_msg_type;
-
-typedef enum {
- /* commands/responses */
- LAPD_CMD_NONE = 0,
-
- LAPD_CMD_I,
- LAPD_CMD_RR,
- LAPD_CMD_RNR,
- LAPD_CMD_REJ,
-
- LAPD_CMD_SABME,
- LAPD_CMD_DM,
- LAPD_CMD_UI,
- LAPD_CMD_DISC,
- LAPD_CMD_UA,
- LAPD_CMD_FRMR,
- LAPD_CMD_XID,
-} lapd_cmd_type;
-
-const char *lapd_cmd_types[] = {
- "NONE",
-
- "I",
- "RR",
- "RNR",
- "REJ",
-
- "SABME",
- "DM",
- "UI",
- "DISC",
- "UA",
- "FRMR",
- "XID",
-
-};
-
-enum lapd_sap_state {
- SAP_STATE_INACTIVE,
- SAP_STATE_SABM_RETRANS,
- SAP_STATE_ACTIVE,
-};
-
-const char *lapd_sap_states[] = {
- "INACTIVE",
- "SABM_RETRANS",
- "ACTIVE",
-};
-
-const char *lapd_msg_types = "?ISU";
-
-/* structure representing an allocated TEI within a LAPD instance */
-struct lapd_tei {
- struct llist_head list;
- struct lapd_instance *li;
- uint8_t tei;
- lapd_tei_state state;
-
- struct llist_head sap_list;
-};
-
-/* Structure representing a SAP within a TEI. We use this for TE-mode to
- * re-transmit SABM */
-struct lapd_sap {
- struct llist_head list;
- struct lapd_tei *tei;
- uint8_t sapi;
- enum lapd_sap_state state;
-
- /* A valid N(R) value is one that is in the range V(A) ≤ N(R) ≤ V(S). */
- int vs; /* next to be transmitted */
- int va; /* last acked by peer */
- int vr; /* next expected to be received */
-
- struct osmo_timer_list sabme_timer; /* timer to re-transmit SABM message */
-};
-
-/* 3.5.2.2 Send state variable V(S)
- * Each point-to-point data link connection endpoint shall have an associated V(S) when using I frame
- * commands. V(S) denotes the sequence number of the next I frame to be transmitted. The V(S) can
- * take on the value 0 through n minus 1. The value of V(S) shall be incremented by 1 with each
- * successive I frame transmission, and shall not exceed V(A) by more than the maximum number of
- * outstanding I frames k. The value of k may be in the range of 1 ≤ k ≤ 127.
- *
- * 3.5.2.3 Acknowledge state variable V(A)
- * Each point-to-point data link connection endpoint shall have an associated V(A) when using I frame
- * commands and supervisory frame commands/responses. V(A) identifies the last I frame that has been
- * acknowledged by its peer [V(A) − 1 equals the N(S) of the last acknowledged I frame]. V(A) can
- * take on the value 0 through n minus 1. The value of V(A) shall be updated by the valid N(R) values
- * received from its peer (see 3.5.2.6). A valid N(R) value is one that is in the range V(A) ≤ N(R) ≤
- * V(S).
- *
- * 3.5.2.5 Receive state variable V(R)
- * Each point-to-point data link connection endpoint shall have an associated V(R) when using I frame
- * commands and supervisory frame commands/responses. V(R) denotes the sequence number of the
- * next in-sequence I frame expected to be received. V(R) can take on the value 0 through n minus 1.
- * The value of V(R) shall be incremented by one with the receipt of an error-free, in-sequence I frame
- * whose N(S) equals V(R).
- */
-#define LAPD_NS(sap) (sap->vs)
-#define LAPD_NR(sap) (sap->vr)
-
-/* 3.5.2.4 Send sequence number N(S)
- * Only I frames contain N(S), the send sequence number of transmitted I frames. At the time that an in-
- * sequence I frame is designated for transmission, the value of N(S) is set equal to V(S).
- *
- * 3.5.2.6 Receive sequence number N(R)
- * All I frames and supervisory frames contain N(R), the expected send sequence number of the next
- * received I frame. At the time that a frame of the above types is designated for transmission, the value
- * of N(R) is set equal to V(R). N(R) indicates that the data link layer entity transmitting the N(R) has
- * correctly received all I frames numbered up to and including N(R) − 1.
- */
-
-/* Resolve TEI structure from given numeric TEI */
-static struct lapd_tei *teip_from_tei(struct lapd_instance *li, uint8_t tei)
-{
- struct lapd_tei *lt;
-
- llist_for_each_entry(lt, &li->tei_list, list) {
- if (lt->tei == tei)
- return lt;
- }
- return NULL;
-};
-
-static void lapd_tei_set_state(struct lapd_tei *teip, int newstate)
-{
- LOGP(DMI, LOGL_INFO, "LAPD state change on TEI %d: %s -> %s\n", teip->tei,
- lapd_tei_states[teip->state], lapd_tei_states[newstate]);
- teip->state = newstate;
-};
-
-/* Allocate a new TEI */
-struct lapd_tei *lapd_tei_alloc(struct lapd_instance *li, uint8_t tei)
-{
- struct lapd_tei *teip;
-
- teip = talloc_zero(li, struct lapd_tei);
- if (!teip)
- return NULL;
-
- teip->li = li;
- teip->tei = tei;
- llist_add(&teip->list, &li->tei_list);
- INIT_LLIST_HEAD(&teip->sap_list);
-
- lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
-
- return teip;
-}
-
-/* Find a SAP within a given TEI */
-static struct lapd_sap *lapd_sap_find(struct lapd_tei *teip, uint8_t sapi)
-{
- struct lapd_sap *sap;
-
- llist_for_each_entry(sap, &teip->sap_list, list) {
- if (sap->sapi == sapi)
- return sap;
- }
-
- return NULL;
-}
-
-static void sabme_timer_cb(void *_sap);
-
-/* Allocate a new SAP within a given TEI */
-static struct lapd_sap *lapd_sap_alloc(struct lapd_tei *teip, uint8_t sapi)
-{
- struct lapd_sap *sap = talloc_zero(teip, struct lapd_sap);
-
- LOGP(DMI, LOGL_INFO, "LAPD Allocating SAP for SAPI=%u / TEI=%u\n",
- sapi, teip->tei);
-
- sap->sapi = sapi;
- sap->tei = teip;
- sap->sabme_timer.cb = &sabme_timer_cb;
- sap->sabme_timer.data = sap;
-
- llist_add(&sap->list, &teip->sap_list);
-
- return sap;
-}
-
-static void lapd_sap_set_state(struct lapd_tei *teip, uint8_t sapi,
- enum lapd_sap_state newstate)
-{
- struct lapd_sap *sap = lapd_sap_find(teip, sapi);
- if (!sap)
- return;
-
- LOGP(DMI, LOGL_INFO, "LAPD state change on TEI %u / SAPI %u: "
- "%s -> %s\n", teip->tei, sapi,
- lapd_sap_states[sap->state], lapd_sap_states[newstate]);
- switch (sap->state) {
- case SAP_STATE_SABM_RETRANS:
- if (newstate != SAP_STATE_SABM_RETRANS)
- osmo_timer_del(&sap->sabme_timer);
- break;
- default:
- if (newstate == SAP_STATE_SABM_RETRANS)
- osmo_timer_schedule(&sap->sabme_timer, SABM_INTERVAL);
- break;
- }
-
- sap->state = newstate;
-};
-
-/* Input function into TEI manager */
-static void lapd_tei_receive(struct lapd_instance *li, uint8_t *data, int len)
-{
- uint8_t entity = data[0];
- uint8_t ref = data[1];
- uint8_t mt = data[3];
- uint8_t action = data[4] >> 1;
- uint8_t e = data[4] & 1;
- uint8_t resp[8];
- struct lapd_tei *teip;
-
- DEBUGP(DMI, "LAPD TEIMGR: entity %x, ref %x, mt %x, action %x, e %x\n",
- entity, ref, mt, action, e);
-
- switch (mt) {
- case 0x01: /* IDENTITY REQUEST */
- DEBUGP(DMI, "LAPD TEIMGR: identity request for TEI %u\n", action);
-
- teip = teip_from_tei(li, action);
- if (!teip) {
- LOGP(DMI, LOGL_INFO, "TEI MGR: New TEI %u\n", action);
- teip = lapd_tei_alloc(li, action);
- }
-
- /* Send ACCEPT */
- memmove(resp, "\xfe\xff\x03\x0f\x00\x00\x02\x00", 8);
- resp[7] = (action << 1) | 1;
- li->transmit_cb(resp, 8, li->cbdata);
-
- if (teip->state == LAPD_TEI_NONE)
- lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
- break;
- default:
- LOGP(DMI, LOGL_NOTICE, "LAPD TEIMGR: unknown mt %x action %x\n",
- mt, action);
- break;
- };
-};
-
-/* General input function for any data received for this LAPD instance */
-uint8_t *
-lapd_receive(struct lapd_instance *li, uint8_t * data, unsigned int len,
- int *ilen, lapd_mph_type *prim, int *error)
-{
- uint8_t sapi, cr, tei, command;
- int pf, ns, nr;
- uint8_t *contents;
- struct lapd_tei *teip;
- struct lapd_sap *sap;
-
- uint8_t resp[8];
- int l = 0;
-
- *ilen = 0;
- *prim = 0;
-
- if (len < 2) {
- LOGP(DMI, LOGL_ERROR, "LAPD receive len %d < 2, ignoring\n", len);
- *error = LAPD_ERR_BAD_LEN;
- return NULL;
- };
-
- if ((data[0] & 1) != 0 || (data[1] & 1) != 1) {
- LOGP(DMI, LOGL_ERROR, "LAPD address field %x/%x not well formed\n",
- data[0], data[1]);
- *error = LAPD_ERR_BAD_ADDR;
- return NULL;
- };
-
- sapi = data[0] >> 2;
- cr = (data[0] >> 1) & 1;
- tei = data[1] >> 1;
- command = li->network_side ^ cr;
- //DEBUGP(DMI, " address sapi %x tei %d cmd %d cr %d\n", sapi, tei, command, cr);
-
- if (len < 3) {
- LOGP(DMI, LOGL_ERROR, "LAPD receive len %d < 3, ignoring\n", len);
- *error = LAPD_ERR_BAD_LEN;
- return NULL;
- };
-
- lapd_msg_type typ = 0;
- lapd_cmd_type cmd = 0;
- pf = -1;
- ns = -1;
- nr = -1;
- if ((data[2] & 1) == 0) {
- typ = LAPD_TYPE_I;
- if (len < 4) {
- LOGP(DMI, LOGL_ERROR, "LAPD I frame, len %d < 4\n", len);
- *error = LAPD_ERR_BAD_LEN;
- return NULL;
- }
- ns = data[2] >> 1;
- nr = data[3] >> 1;
- pf = data[3] & 1;
- cmd = LAPD_CMD_I;
- } else if ((data[2] & 3) == 1) {
- typ = LAPD_TYPE_S;
- if (len < 4) {
- LOGP(DMI, LOGL_ERROR, "LAPD S frame, len %d < 4\n", len);
- *error = LAPD_ERR_BAD_LEN;
- return NULL;
- }
- nr = data[3] >> 1;
- pf = data[3] & 1;
- switch (data[2]) {
- case 0x1:
- cmd = LAPD_CMD_RR;
- break;
- case 0x5:
- cmd = LAPD_CMD_RNR;
- break;
- case 0x9:
- cmd = LAPD_CMD_REJ;
- break;
- default:
- LOGP(DMI, LOGL_ERROR, "LAPD unknown S cmd %x\n", data[2]);
- *error = LAPD_ERR_UNKNOWN_S_CMD;
- return NULL;
- };
- } else if ((data[2] & 3) == 3) {
- typ = LAPD_TYPE_U;
- pf = (data[2] >> 4) & 1;
- int val = data[2] & ~(1 << 4);
- switch (val) {
- case 0x6f:
- cmd = LAPD_CMD_SABME;
- break;
- case 0x0f:
- cmd = LAPD_CMD_DM;
- break;
- case 0x03:
- cmd = LAPD_CMD_UI;
- break;
- case 0x43:
- cmd = LAPD_CMD_DISC;
- break;
- case 0x63:
- cmd = LAPD_CMD_UA;
- break;
- case 0x87:
- cmd = LAPD_CMD_FRMR;
- break;
- case 0xaf:
- cmd = LAPD_CMD_XID;
- break;
-
- default:
- LOGP(DMI, LOGL_ERROR, "LAPD unknown U cmd %x "
- "(pf %x data %x)\n", val, pf, data[2]);
- *error = LAPD_ERR_UNKNOWN_U_CMD;
- return NULL;
- };
- };
-
- contents = &data[4];
- if (typ == LAPD_TYPE_U)
- contents--;
- *ilen = len - (contents - data);
-
- if (tei == 127)
- lapd_tei_receive(li, contents, *ilen);
-
- teip = teip_from_tei(li, tei);
- if (!teip) {
- LOGP(DMI, LOGL_NOTICE, "LAPD Unknown TEI %u\n", tei);
- *error = LAPD_ERR_UNKNOWN_TEI;
- return NULL;
- }
-
- sap = lapd_sap_find(teip, sapi);
- if (!sap) {
- LOGP(DMI, LOGL_INFO, "LAPD No SAP for TEI=%u / SAPI=%u, "
- "allocating\n", tei, sapi);
- sap = lapd_sap_alloc(teip, sapi);
- }
-
- DEBUGP(DMI, "<- %c %s sapi %x tei %3d cmd %x pf %x ns %3d nr %3d "
- "ilen %d teip %p vs %d va %d vr %d len %d\n",
- lapd_msg_types[typ], lapd_cmd_types[cmd], sapi, tei, command, pf,
- ns, nr, *ilen, teip, sap->vs, sap->va, sap->vr, len);
-
- switch (cmd) {
- case LAPD_CMD_I:
- if (ns != sap->vr) {
- DEBUGP(DMI, "LAPD ns %d != vr %d\n", ns, sap->vr);
- if (ns == ((sap->vr - 1) & 0x7f)) {
- LOGP(DMI, LOGL_NOTICE, "LAPD double frame, "
- "ignoring\n");
- cmd = 0; // ignore
- } else {
- LOGP(DMI, LOGL_ERROR, "LAPD Out of order "
- "ns %d != vr %d, ignoring\n", ns, sap->vr);
- return NULL;
- };
- } else {
- //printf("IN SEQUENCE\n");
- sap->vr = (ns + 1) & 0x7f; // FIXME: hack!
- };
-
- break;
- case LAPD_CMD_UI:
- break;
- case LAPD_CMD_SABME:
- sap->vs = 0;
- sap->vr = 0;
- sap->va = 0;
-
- // ua
- resp[l++] = data[0];
- resp[l++] = (tei << 1) | 1;
- resp[l++] = 0x73;
- li->transmit_cb(resp, l, li->cbdata);
- if (teip->state != LAPD_TEI_ACTIVE) {
- if (teip->state == LAPD_TEI_ASSIGNED) {
- lapd_tei_set_state(teip,
- LAPD_TEI_ACTIVE);
- //printf("ASSIGNED and ACTIVE\n");
- } else {
-#if 0
- DEBUGP(DMI, "rr in strange state, send rej\n");
-
- // rej
- resp[l++] = (sap-> sapi << 2) | (li->network_side ? 0 : 2);
- resp[l++] = (tei << 1) | 1;
- resp[l++] = 0x09; //rej
- resp[l++] = ((sap->vr + 1) << 1) | 0;
- li->transmit_cb(resp, l, li->cbdata);
- pf = 0; // dont reply
-#endif
- };
- };
-
- *prim = LAPD_MPH_ACTIVATE_IND;
- break;
- case LAPD_CMD_UA:
- sap->vs = 0;
- sap->vr = 0;
- sap->va = 0;
- lapd_tei_set_state(teip, LAPD_TEI_ACTIVE);
- lapd_sap_set_state(teip, sapi, SAP_STATE_ACTIVE);
- *prim = LAPD_MPH_ACTIVATE_IND;
- break;
- case LAPD_CMD_RR:
- sap->va = (nr & 0x7f);
-#if 0
- if (teip->state != LAPD_TEI_ACTIVE) {
- if (teip->state == LAPD_TEI_ASSIGNED) {
- lapd_tei_set_state(teip, LAPD_TEI_ACTIVE);
- *prim = LAPD_MPH_ACTIVATE_IND;
- //printf("ASSIGNED and ACTIVE\n");
- } else {
-#if 0
- DEBUGP(DMI, "rr in strange " "state, send rej\n");
-
- // rej
- resp[l++] = (sap-> sapi << 2) | (li->network_side ? 0 : 2);
- resp[l++] = (tei << 1) | 1;
- resp[l++] = 0x09; //rej
- resp[l++] =
- ((sap->vr + 1) << 1) | 0;
- li->transmit_cb(resp, l, li->cbdata);
- pf = 0; // dont reply
-#endif
- };
- };
-#endif
- if (pf) {
- // interrogating us, send rr
- resp[l++] = data[0];
- resp[l++] = (tei << 1) | 1;
- resp[l++] = 0x01; // rr
- resp[l++] = (LAPD_NR(sap) << 1) | (data[3] & 1); // pf bit from req
-
- li->transmit_cb(resp, l, li->cbdata);
-
- };
- break;
- case LAPD_CMD_FRMR:
- // frame reject
-#if 0
- if (teip->state == LAPD_TEI_ACTIVE)
- *prim = LAPD_MPH_DEACTIVATE_IND;
- lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
-#endif
- LOGP(DMI, LOGL_NOTICE, "frame reject, ignoring\n");
- break;
- case LAPD_CMD_DISC:
- // disconnect
- resp[l++] = data[0];
- resp[l++] = (tei << 1) | 1;
- resp[l++] = 0x73;
- li->transmit_cb(resp, l, li->cbdata);
- lapd_tei_set_state(teip, LAPD_TEI_NONE);
- break;
- default:
- LOGP(DMI, LOGL_NOTICE, "unknown cmd for tei %d (cmd %x)\n",
- tei, cmd);
- break;
- }
-
- if (typ == LAPD_TYPE_I) {
- /* send rr
- * Thu Jan 22 19:17:13 2009 <4000> sangoma.c:340 read (62/25) 4: fa 33 01 0a
- * lapd <- S RR sapi 3e tei 25 cmd 0 pf 0 ns -1 nr 5 ilen 0 teip 0x613800 vs 7 va 5 vr 2 len 4
- */
-
- /* interrogating us, send rr */
- DEBUGP(DMI, "LAPD Sending RR response\n");
- resp[l++] = data[0];
- resp[l++] = (tei << 1) | 1;
- resp[l++] = 0x01; // rr
- resp[l++] = (LAPD_NR(sap) << 1) | (data[3] & 1); // pf bit from req
-
- li->transmit_cb(resp, l, li->cbdata);
-
- if (cmd != 0) {
- *prim = LAPD_DL_DATA_IND;
- return contents;
- }
- } else if (tei != 127 && typ == LAPD_TYPE_U && cmd == LAPD_CMD_UI) {
- *prim = LAPD_DL_UNITDATA_IND;
- return contents;
- }
-
- *error = LAPD_ERR_BAD_CMD;
- return NULL;
-};
-
-/* low-level function to send a single SABM message */
-static int lapd_send_sabm(struct lapd_instance *li, uint8_t tei, uint8_t sapi)
-{
- struct msgb *msg = msgb_alloc_headroom(1024, 128, "LAPD SABM");
- if (!msg)
- return -ENOMEM;
-
- LOGP(DMI, LOGL_INFO, "LAPD Sending SABM for TEI=%u, SAPI=%u\n", tei, sapi);
-
- msgb_put_u8(msg, (sapi << 2) | (li->network_side ? 2 : 0));
- msgb_put_u8(msg, (tei << 1) | 1);
- msgb_put_u8(msg, 0x7F);
-
- li->transmit_cb(msg->data, msg->len, li->cbdata);
-
- msgb_free(msg);
-
- return 0;
-}
-
-/* timer call-back function for SABM re-transmission */
-static void sabme_timer_cb(void *_sap)
-{
- struct lapd_sap *sap = _sap;
-
- lapd_send_sabm(sap->tei->li, sap->tei->tei, sap->sapi);
-
- if (sap->state == SAP_STATE_SABM_RETRANS)
- osmo_timer_schedule(&sap->sabme_timer, SABM_INTERVAL);
-}
-
-/* Start a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */
-int lapd_sap_start(struct lapd_instance *li, uint8_t tei, uint8_t sapi)
-{
- struct lapd_sap *sap;
- struct lapd_tei *teip;
-
- teip = teip_from_tei(li, tei);
- if (!teip)
- teip = lapd_tei_alloc(li, tei);
-
- sap = lapd_sap_find(teip, sapi);
- if (sap)
- return -EEXIST;
-
- sap = lapd_sap_alloc(teip, sapi);
-
- lapd_sap_set_state(teip, sapi, SAP_STATE_SABM_RETRANS);
-
- return 0;
-}
-
-/* Stop a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */
-int lapd_sap_stop(struct lapd_instance *li, uint8_t tei, uint8_t sapi)
-{
- struct lapd_tei *teip;
- struct lapd_sap *sap;
-
- teip = teip_from_tei(li, tei);
- if (!teip)
- return -ENODEV;
-
- sap = lapd_sap_find(teip, sapi);
- if (!sap)
- return -ENODEV;
-
- lapd_sap_set_state(teip, sapi, SAP_STATE_INACTIVE);
-
- llist_del(&sap->list);
- talloc_free(sap);
-
- return 0;
-}
-
-/* Transmit Data (I-Frame) on the given LAPD Instance / TEI / SAPI */
-void lapd_transmit(struct lapd_instance *li, uint8_t tei, uint8_t sapi,
- uint8_t *data, unsigned int len)
-{
- struct lapd_tei *teip = teip_from_tei(li, tei);
- struct lapd_sap *sap;
-
- if (!teip) {
- LOGP(DMI, LOGL_ERROR, "LAPD Cannot transmit on "
- "non-existing TEI %u\n", tei);
- return;
- }
-
- sap = lapd_sap_find(teip, sapi);
- if (!sap) {
- LOGP(DMI, LOGL_INFO, "LAPD Tx on unknown SAPI=%u "
- "in TEI=%u, allocating\n", sapi, tei);
- sap = lapd_sap_alloc(teip, sapi);
- }
-
- /* prepend stuff */
- uint8_t buf[10000];
- memset(buf, 0, sizeof(buf));
- memmove(buf + 4, data, len);
- len += 4;
-
- buf[0] = (sapi << 2) | (li->network_side ? 2 : 0);
- buf[1] = (tei << 1) | 1;
- buf[2] = (LAPD_NS(sap) << 1);
- buf[3] = (LAPD_NR(sap) << 1) | 0;
-
- sap->vs = (sap->vs + 1) & 0x7f;
-
- li->transmit_cb(buf, len, li->cbdata);
-};
-
-/* Allocate a new LAPD instance */
-struct lapd_instance *lapd_instance_alloc(int network_side,
- void (*tx_cb)(uint8_t *data, int len,
- void *cbdata), void *cbdata)
-{
- struct lapd_instance *li;
-
- li = talloc_zero(NULL, struct lapd_instance);
- if (!li)
- return NULL;
-
- li->transmit_cb = tx_cb;
- li->cbdata = cbdata;
- li->network_side = network_side;
- INIT_LLIST_HEAD(&li->tei_list);
-
- return li;
-}