[LAPD] Support multiple instances of LAPD
We cannot afford static/global state, as we may have multiple E1
lines, each having its own LAPD instance. Furthermore, we might
even have multiple LAPD instances on the same E1 line (think of
a multi-drop setup).
This also implements dynamic TEI allocation, i.e. no hardcoded
TEI list anymore.
diff --git a/openbsc/include/openbsc/e1_input.h b/openbsc/include/openbsc/e1_input.h
index ca8d5a6..95b9dd1 100644
--- a/openbsc/include/openbsc/e1_input.h
+++ b/openbsc/include/openbsc/e1_input.h
@@ -87,7 +87,11 @@
/* ip.access driver has one fd for each ts */
struct bsc_fd fd;
} ipaccess;
-
+ struct {
+ /* DAHDI driver has one fd for each ts */
+ struct bsc_fd fd;
+ struct lapd_instance *lapd;
+ } dahdi;
} driver;
};
diff --git a/openbsc/src/input/dahdi.c b/openbsc/src/input/dahdi.c
index ebdaccf..7a3c2be 100644
--- a/openbsc/src/input/dahdi.c
+++ b/openbsc/src/input/dahdi.c
@@ -63,6 +63,7 @@
lapd_mph_type prim;
unsigned int sapi, tei;
int ilen, ret;
+ uint8_t *idata;
if (!msg)
return -ENOMEM;
@@ -81,7 +82,9 @@
DEBUGP(DMI, "<= len = %d, sapi(%d) tei(%d)", ret, sapi, tei);
- uint8_t *idata = lapd_receive(msg->data, msg->len, &ilen, &prim, bfd);
+ idata = lapd_receive(e1i_ts->driver.dahdi.lapd, msg->data, msg->len, &ilen, &prim);
+ if (!idata)
+ return -EIO;
msgb_pull(msg, 2);
@@ -126,7 +129,7 @@
return 0;
}
- e1i_ts->driver.misdn.fd.when |= BSC_FD_WRITE;
+ e1i_ts->driver.dahdi.fd.when |= BSC_FD_WRITE;
return 0;
}
@@ -167,7 +170,7 @@
return 0;
}
- lapd_transmit(sign_link->tei, msg->data, msg->len, bfd);
+ lapd_transmit(e1i_ts->driver.dahdi.lapd, sign_link->tei, msg->data, msg->len);
msgb_free(msg);
/* set tx delay timer for next event */
@@ -353,7 +356,7 @@
}
-static int dahdi_e1_setup(struct e1inp_line *line, int release_l2)
+static int dahdi_e1_setup(struct e1inp_line *line)
{
int ts, ret;
@@ -362,7 +365,7 @@
unsigned int idx = ts-1;
char openstr[128];
struct e1inp_ts *e1i_ts = &line->ts[idx];
- struct bsc_fd *bfd = &e1i_ts->driver.misdn.fd;
+ struct bsc_fd *bfd = &e1i_ts->driver.dahdi.fd;
bfd->data = line;
bfd->priv_nr = ts;
@@ -382,6 +385,7 @@
}
bfd->when = BSC_FD_READ;
dahdi_set_bufinfo(bfd->fd, 1);
+ e1i_ts->driver.dahdi.lapd = lapd_instance_alloc(dahdi_write_msg, bfd);
break;
case E1INP_TS_TYPE_TRAU:
bfd->fd = open(openstr, O_RDWR | O_NONBLOCK);
@@ -417,24 +421,16 @@
static int dahdi_e1_line_update(struct e1inp_line *line)
{
- int ret;
-
if (line->driver != &dahdi_driver)
return -EINVAL;
- init_flip_bits();
-
- ret = dahdi_e1_setup(line, 1);
- if (ret)
- return ret;
-
- lapd_transmit_cb = dahdi_write_msg;
-
- return 0;
+ return dahdi_e1_setup(line);
}
int e1inp_dahdi_init(void)
{
+ init_flip_bits();
+
/* register the driver with the core */
return e1inp_driver_register(&dahdi_driver);
}
diff --git a/openbsc/src/input/lapd.c b/openbsc/src/input/lapd.c
index 99069b4..d488bfd 100644
--- a/openbsc/src/input/lapd.c
+++ b/openbsc/src/input/lapd.c
@@ -1,7 +1,26 @@
+/* OpenBSC minimal LAPD implementation */
-/*
- * minimal standalone network-side lap-d implementation
- * oystein@homelien.no, 2009
+/* (C) 2009 by oystein@homelien.no
+ * (C) 2011 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2010 by Digium and Matthew Fredrickson <creslin@digium.com>
+ *
+ * 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.
+ *
*/
#include <stdio.h>
@@ -9,7 +28,10 @@
#include <assert.h>
#include "lapd.h"
-#include "openbsc/debug.h"
+
+#include <osmocore/linuxlist.h>
+#include <osmocore/talloc.h>
+#include <openbsc/debug.h>
typedef enum {
LAPD_TEI_NONE = 0,
@@ -70,17 +92,18 @@
};
const char *lapd_msg_types = "?ISU";
-const int network_side = 1; /* 0 for user side */
-typedef struct {
- int tei;
- int sapi;
+struct lapd_tei {
+ struct llist_head list;
+
+ uint8_t tei;
+ uint8_t sapi;
/* 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 */
lapd_tei_state state;
-} lapd_tei_t;
+};
/* 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
@@ -117,63 +140,59 @@
* 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.
*/
-void (*lapd_transmit_cb) (uint8_t * data, int len, void *cbdata);
-static lapd_tei_t tei_list[] = {
- {25, 62,},
- {1, 0,},
- {-1},
-};
-
-static lapd_tei_t *teip_from_tei(int tei)
+static struct lapd_tei *teip_from_tei(struct lapd_instance *li, uint8_t tei)
{
- lapd_tei_t *p;
- for (p = tei_list; p->tei != -1; p++) {
- if (p->tei == tei)
- return p;
- };
+ 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(lapd_tei_t * teip, int newstate)
+static void lapd_tei_set_state(struct lapd_tei *teip, int newstate)
{
DEBUGP(DMI, "state change on tei %d: %s -> %s\n", teip->tei,
lapd_tei_states[teip->state], lapd_tei_states[newstate]);
teip->state = newstate;
};
-static void lapd_tei_receive(uint8_t * data, int len, void *cbdata)
+static void lapd_tei_receive(struct lapd_instance *li, uint8_t *data, int len)
{
int entity = data[0];
int ref = data[1];
int mt = data[3];
int action = data[4] >> 1;
int e = data[4] & 1;
+ int tei;
+ uint8_t resp[8];
+ struct lapd_tei *teip;
+
DEBUGP(DMI, "tei mgmt: entity %x, ref %x, mt %x, action %x, e %x\n", entity, ref, mt, action, e);
switch (mt) {
- case 0x01:{ // identity request
- int tei = action;
- uint8_t resp[8];
- lapd_tei_t *teip;
+ case 0x01: /* IDENTITY REQUEST */
+ DEBUGP(DMI, "TEIMGR: identity request for TEI %u\n", tei);
- DEBUGP(DMI, "tei mgmt: identity request, accepting "
- "tei %d\n", tei);
- memmove(resp, "\xfe\xff\x03\x0f\x00\x00\x02\x00", 8);
- resp[7] = (tei << 1) | 1;
- lapd_transmit_cb(resp, 8, cbdata);
-
- teip = teip_from_tei(tei);
- if (!teip) {
- LOGP(DMI, LOGL_NOTICE, "Message for unknown "
- "TEI %u, LAPD code supports only "
- "TEI 25, 1, 2\n", tei);
- return;
- }
- if (teip->state == LAPD_TEI_NONE)
- lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
- break;
+ teip = teip_from_tei(li, tei);
+ if (!teip) {
+ LOGP(DMI, LOGL_INFO, "TEI MGR: New TEI %u\n", tei);
+ teip = talloc_zero(li, struct lapd_tei);
+ teip->tei = tei;
+ llist_add(&teip->list, &li->tei_list);
+ lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
}
+
+ /* Send ACCEPT */
+ memmove(resp, "\xfe\xff\x03\x0f\x00\x00\x02\x00", 8);
+ resp[7] = (tei << 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, "tei mgmt: unknown mt %x action %x\n",
mt, action);
@@ -181,13 +200,13 @@
};
};
-uint8_t *lapd_receive(uint8_t * data, int len, int *ilen, lapd_mph_type * prim,
- void *cbdata)
+uint8_t *lapd_receive(struct lapd_instance *li, uint8_t * data, unsigned int len,
+ int *ilen, lapd_mph_type *prim)
{
uint8_t sapi, cr, tei, command;
int pf, ns, nr;
uint8_t *contents;
- lapd_tei_t *teip;
+ struct lapd_tei *teip;
uint8_t resp[8];
int l = 0;
@@ -209,7 +228,7 @@
sapi = data[0] >> 2;
cr = (data[0] >> 1) & 1;
tei = data[1] >> 1;
- command = network_side ^ cr;
+ command = li->network_side ^ cr;
//DEBUGP(DMI, " address sapi %x tei %d cmd %d cr %d\n", sapi, tei, command, cr);
if (len < 3) {
@@ -288,9 +307,9 @@
*ilen = len - (contents - data);
if (tei == 127)
- lapd_tei_receive(contents, *ilen, cbdata);
+ lapd_tei_receive(li, contents, *ilen);
- teip = teip_from_tei(tei);
+ teip = teip_from_tei(li, tei);
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",
@@ -330,7 +349,7 @@
resp[l++] = data[0];
resp[l++] = (tei << 1) | 1;
resp[l++] = 0x73;
- lapd_transmit_cb(resp, l, cbdata);
+ li->transmit_cb(resp, l, li->cbdata);
if (teip->state != LAPD_TEI_ACTIVE) {
if (teip->state == LAPD_TEI_ASSIGNED) {
lapd_tei_set_state(teip,
@@ -341,11 +360,11 @@
DEBUGP(DMI, "rr in strange state, send rej\n");
// rej
- resp[l++] = (teip-> sapi << 2) | (network_side ? 0 : 2);
+ resp[l++] = (teip-> sapi << 2) | (li->network_side ? 0 : 2);
resp[l++] = (tei << 1) | 1;
resp[l++] = 0x09; //rej
resp[l++] = ((teip->vr + 1) << 1) | 0;
- lapd_transmit_cb(resp, l, cbdata);
+ li->transmit_cb(resp, l, li->cbdata);
pf = 0; // dont reply
#endif
};
@@ -366,13 +385,12 @@
DEBUGP(DMI, "rr in strange " "state, send rej\n");
// rej
- resp[l++] = (teip-> sapi << 2) | (network_side ? 0 : 2);
+ resp[l++] = (teip-> sapi << 2) | (li->network_side ? 0 : 2);
resp[l++] = (tei << 1) | 1;
resp[l++] = 0x09; //rej
resp[l++] =
((teip->vr + 1) << 1) | 0;
- lapd_transmit_cb(resp, l,
- cbdata);
+ li->transmit_cb(resp, l, li->cbdata);
pf = 0; // dont reply
#endif
};
@@ -385,7 +403,7 @@
resp[l++] = 0x01; // rr
resp[l++] = (LAPD_NR(teip) << 1) | (data[3] & 1); // pf bit from req
- lapd_transmit_cb(resp, l, cbdata);
+ li->transmit_cb(resp, l, li->cbdata);
};
break;
@@ -403,7 +421,7 @@
resp[l++] = data[0];
resp[l++] = (tei << 1) | 1;
resp[l++] = 0x73;
- lapd_transmit_cb(resp, l, cbdata);
+ li->transmit_cb(resp, l, li->cbdata);
lapd_tei_set_state(teip, LAPD_TEI_NONE);
break;
default:
@@ -425,7 +443,7 @@
resp[l++] = 0x01; // rr
resp[l++] = (LAPD_NR(teip) << 1) | (data[3] & 1); // pf bit from req
- lapd_transmit_cb(resp, l, cbdata);
+ li->transmit_cb(resp, l, li->cbdata);
if (cmd != 0) {
*prim = LAPD_DL_DATA_IND;
@@ -439,12 +457,18 @@
return NULL;
};
-void lapd_transmit(int tei, uint8_t * data, int len, void *cbdata)
+void lapd_transmit(struct lapd_instance *li, uint8_t tei,
+ uint8_t *data, unsigned int len)
{
//printf("lapd_transmit %d, %d\n", tei, len);
//hexdump(data, len);
- lapd_tei_t *teip = teip_from_tei(tei);
- //printf("teip %p\n", teip);
+ struct lapd_tei *teip = teip_from_tei(li, tei);
+
+ if (!teip) {
+ LOGP(DMI, LOGL_ERROR, "Cannot transmit on non-existing "
+ "TEI %u\n", tei);
+ return;
+ }
/* prepend stuff */
uint8_t buf[10000];
@@ -452,12 +476,29 @@
memmove(buf + 4, data, len);
len += 4;
- buf[0] = (teip->sapi << 2) | (network_side ? 2 : 0);
+ buf[0] = (teip->sapi << 2) | (li->network_side ? 2 : 0);
buf[1] = (teip->tei << 1) | 1;
buf[2] = (LAPD_NS(teip) << 1);
buf[3] = (LAPD_NR(teip) << 1) | 0;
teip->vs = (teip->vs + 1) & 0x7f;
- lapd_transmit_cb(buf, len, cbdata);
+ li->transmit_cb(buf, len, li->cbdata);
};
+
+struct lapd_instance *lapd_instance_alloc(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 = 1;
+ INIT_LLIST_HEAD(&li->tei_list);
+
+ return li;
+}
diff --git a/openbsc/src/input/lapd.h b/openbsc/src/input/lapd.h
index b0e6e6f..f79d84f 100644
--- a/openbsc/src/input/lapd.h
+++ b/openbsc/src/input/lapd.h
@@ -3,6 +3,8 @@
#include <stdint.h>
+#include <osmocore/linuxlist.h>
+
typedef enum {
LAPD_MPH_NONE = 0,
@@ -14,10 +16,22 @@
} lapd_mph_type;
-extern uint8_t *lapd_receive(uint8_t *data, int len, int *ilen, lapd_mph_type *prim, void *cbdata);
+struct lapd_instance {
+ struct llist_head list; /* list of LAPD instances */
+ int network_side;
-extern void (*lapd_transmit_cb)(uint8_t *data, int len, void *cbdata);
+ void (*transmit_cb)(uint8_t *data, int len, void *cbdata);
+ void *cbdata;
-extern void lapd_transmit(int tei, uint8_t *data, int len, void *cbdata);
+ struct llist_head tei_list; /* list of TEI in this LAPD instance */
+};
+
+extern uint8_t *lapd_receive(struct lapd_instance *li, uint8_t *data, unsigned int len,
+ int *ilen, lapd_mph_type *prim);
+
+extern void lapd_transmit(struct lapd_instance *li, uint8_t tei, uint8_t *data, unsigned int len);
+
+struct lapd_instance *lapd_instance_alloc(void (*tx_cb)(uint8_t *data, int len,
+ void *cbdata), void *cbdata);
#endif /* OPENBSC_LAPD_H */