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osmo-msc/openbsc/src/gprs/gprs_llc.c

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Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
2010-03-14 07:45:01 +00:00
/* GPRS LLC protocol implementation as per 3GPP TS 04.64 */
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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/* (C) 2009-2010 by Harald Welte <laforge@gnumonks.org>
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*
* 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 <errno.h>
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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#include <stdint.h>
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#include <osmocore/msgb.h>
#include <osmocore/linuxlist.h>
#include <osmocore/timer.h>
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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#include <osmocore/talloc.h>
#include <openbsc/gsm_data.h>
#include <openbsc/debug.h>
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#include <openbsc/gprs_bssgp.h>
#include <openbsc/gprs_llc.h>
#include <openbsc/crc24.h>
/* Section 4.5.2 Logical Link States + Annex C.2 */
enum gprs_llc_ll_state {
GPRS_LLS_UNASSIGNED = 1, /* No TLLI yet */
GPRS_LLS_ASSIGNED_ADM = 2, /* TLLI assigned */
GPRS_LLS_LOCAL_EST = 3, /* Local Establishment */
GPRS_LLS_REMOTE_EST = 4, /* Remote Establishment */
GPRS_LLS_ABM = 5,
GPRS_LLS_LOCAL_REL = 6, /* Local Release */
GPRS_LLS_TIMER_REC = 7, /* Timer Recovery */
};
/* Section 4.7.1: Logical Link Entity: One per DLCI (TLLI + SAPI) */
struct gprs_llc_lle {
struct llist_head list;
struct timer_list t200;
struct timer_list t201; /* wait for acknowledgement */
enum gprs_llc_ll_state state;
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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uint32_t tlli;
uint32_t sapi;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
2010-03-14 07:45:01 +00:00
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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uint8_t v_sent;
uint8_t v_ack;
uint8_t v_recv;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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unsigned int n200;
unsigned int retrans_ctr;
[gprs] SGSN: Expect all Identifiers to be stored at highest level We now expect the highest level (actual SGSN GMM code) to know all identifiers for every element in the protocol stack, i.e. TLLI, SAPI, BVCI and NSEI. The layer-inetrnal state is looked up based on those identifiers. The reason for this is to ensure only the highest level state needs to be persistent, while everything else can be regenerated dynamically (e.g. in a SGSN restart)
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/* over which BSSGP BTS ctx do we need to transmit */
uint16_t bvci;
uint16_t nsei;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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};
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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static LLIST_HEAD(gprs_llc_lles);
void *llc_tall_ctx;
/* lookup LLC Entity based on DLCI (TLLI+SAPI tuple) */
static struct gprs_llc_lle *lle_by_tlli_sapi(uint32_t tlli, uint32_t sapi)
{
struct gprs_llc_lle *lle;
llist_for_each_entry(lle, &gprs_llc_lles, list) {
if (lle->tlli == tlli && lle->sapi == sapi)
return lle;
}
return NULL;
}
static struct gprs_llc_lle *lle_alloc(uint32_t tlli, uint32_t sapi)
{
struct gprs_llc_lle *lle;
lle = talloc_zero(llc_tall_ctx, struct gprs_llc_lle);
if (!lle)
return NULL;
lle->tlli = tlli;
lle->sapi = sapi;
lle->state = GPRS_LLS_UNASSIGNED;
llist_add(&lle->list, &gprs_llc_lles);
return lle;
}
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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enum gprs_llc_cmd {
GPRS_LLC_NULL,
GPRS_LLC_RR,
GPRS_LLC_ACK,
GPRS_LLC_RNR,
GPRS_LLC_SACK,
GPRS_LLC_DM,
GPRS_LLC_DISC,
GPRS_LLC_UA,
GPRS_LLC_SABM,
GPRS_LLC_FRMR,
GPRS_LLC_XID,
};
struct gprs_llc_hdr_parsed {
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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uint8_t sapi;
uint8_t is_cmd:1,
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ack_req:1,
is_encrypted:1;
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uint32_t seq_rx;
uint32_t seq_tx;
uint32_t fcs;
uint32_t fcs_calc;
uint8_t *data;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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uint16_t data_len;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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enum gprs_llc_cmd cmd;
};
#define LLC_ALLOC_SIZE 16384
#define UI_HDR_LEN 3
#define N202 4
#define CRC24_LENGTH 3
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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static int gprs_llc_fcs(uint8_t *data, unsigned int len)
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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{
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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uint32_t fcs_calc;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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fcs_calc = crc24_calc(INIT_CRC24, data, len);
fcs_calc = ~fcs_calc;
fcs_calc &= 0xffffff;
return fcs_calc;
}
static void t200_expired(void *data)
{
struct gprs_llc_lle *lle = data;
/* 8.5.1.3: Expiry of T200 */
if (lle->retrans_ctr >= lle->n200) {
/* FIXME: LLGM-STATUS-IND, LL-RELEASE-IND/CNF */
lle->state = GPRS_LLS_ASSIGNED_ADM;
}
switch (lle->state) {
case GPRS_LLS_LOCAL_EST:
/* retransmit SABM */
/* re-start T200 */
lle->retrans_ctr++;
break;
case GPRS_LLS_LOCAL_REL:
/* retransmit DISC */
/* re-start T200 */
lle->retrans_ctr++;
break;
}
}
static void t201_expired(void *data)
{
struct gprs_llc_lle *lle = data;
if (lle->retrans_ctr < lle->n200) {
/* transmit apropriate supervisory frame (8.6.4.1) */
/* set timer T201 */
lle->retrans_ctr++;
}
}
[gprs] LLC: API to send XID responses to XID commands
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int gprs_llc_tx_u(struct msgb *msg, uint8_t sapi, int command,
enum gprs_llc_u_cmd u_cmd, int pf_bit)
{
uint8_t *fcs, *llch;
uint8_t addr, ctrl;
uint32_t fcs_calc;
/* Identifiers from UP: (TLLI, SAPI) + (BVCI, NSEI) */
/* Address Field */
addr = sapi & 0xf;
if (command)
addr |= 0x40;
/* 6.3 Figure 8 */
ctrl = 0xe0 | u_cmd;
if (pf_bit)
ctrl |= 0x10;
/* prepend LLC UI header */
llch = msgb_push(msg, 2);
llch[0] = addr;
llch[1] = ctrl;
/* append FCS to end of frame */
fcs = msgb_put(msg, 3);
fcs_calc = gprs_llc_fcs(llch, fcs - llch);
fcs[0] = fcs_calc & 0xff;
fcs[1] = (fcs_calc >> 8) & 0xff;
fcs[2] = (fcs_calc >> 16) & 0xff;
/* Identifiers passed down: (BVCI, NSEI) */
return gprs_bssgp_tx_dl_ud(msg);
}
/* Send XID response to LLE */
static int gprs_llc_tx_xid(struct gprs_llc_lle *lle, struct msgb *msg)
{
/* copy identifiers from LLE to ensure lower layers can route */
msgb_tlli(msg) = lle->tlli;
msgb_bvci(msg) = lle->bvci;
msgb_nsei(msg) = lle->nsei;
return gprs_llc_tx_u(msg, lle->sapi, 0, GPRS_LLC_U_XID, 1);
}
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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/* Transmit a UI frame over the given SAPI */
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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int gprs_llc_tx_ui(struct msgb *msg, uint8_t sapi, int command)
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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{
[gprs] SGSN: Expect all Identifiers to be stored at highest level We now expect the highest level (actual SGSN GMM code) to know all identifiers for every element in the protocol stack, i.e. TLLI, SAPI, BVCI and NSEI. The layer-inetrnal state is looked up based on those identifiers. The reason for this is to ensure only the highest level state needs to be persistent, while everything else can be regenerated dynamically (e.g. in a SGSN restart)
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struct gprs_llc_lle *lle;
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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uint8_t *fcs, *llch;
uint8_t addr, ctrl[2];
uint32_t fcs_calc;
uint16_t nu = 0;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
2010-03-14 07:45:01 +00:00
[gprs] SGSN: Expect all Identifiers to be stored at highest level We now expect the highest level (actual SGSN GMM code) to know all identifiers for every element in the protocol stack, i.e. TLLI, SAPI, BVCI and NSEI. The layer-inetrnal state is looked up based on those identifiers. The reason for this is to ensure only the highest level state needs to be persistent, while everything else can be regenerated dynamically (e.g. in a SGSN restart)
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/* Identifiers from UP: (TLLI, SAPI) + (BVCI, NSEI) */
/* look-up or create the LL Entity for this (TLLI, SAPI) tuple */
lle = lle_by_tlli_sapi(msgb_tlli(msg), sapi);
if (!lle)
lle = lle_alloc(msgb_tlli(msg), sapi);
/* Update LLE's (BVCI, NSEI) tuple */
lle->bvci = msgb_bvci(msg);
lle->nsei = msgb_nsei(msg);
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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/* Address Field */
addr = sapi & 0xf;
if (command)
addr |= 0x40;
/* Control Field */
ctrl[0] = 0xc0;
ctrl[0] |= nu >> 6;
ctrl[1] = (nu << 2) & 0xfc;
ctrl[1] |= 0x01; /* Protected Mode */
/* prepend LLC UI header */
llch = msgb_push(msg, 3);
llch[0] = addr;
llch[1] = ctrl[0];
llch[2] = ctrl[1];
/* append FCS to end of frame */
fcs = msgb_put(msg, 3);
fcs_calc = gprs_llc_fcs(llch, fcs - llch);
fcs[0] = fcs_calc & 0xff;
fcs[1] = (fcs_calc >> 8) & 0xff;
fcs[2] = (fcs_calc >> 16) & 0xff;
[gprs] SGSN: Expect all Identifiers to be stored at highest level We now expect the highest level (actual SGSN GMM code) to know all identifiers for every element in the protocol stack, i.e. TLLI, SAPI, BVCI and NSEI. The layer-inetrnal state is looked up based on those identifiers. The reason for this is to ensure only the highest level state needs to be persistent, while everything else can be regenerated dynamically (e.g. in a SGSN restart)
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/* Identifiers passed down: (BVCI, NSEI) */
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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return gprs_bssgp_tx_dl_ud(msg);
}
static int gprs_llc_hdr_dump(struct gprs_llc_hdr_parsed *gph)
{
DEBUGP(DGPRS, "LLC SAPI=%u %c %c FCS=0x%06x(%s) ",
gph->sapi, gph->is_cmd ? 'C' : 'R', gph->ack_req ? 'A' : ' ',
gph->fcs, gph->fcs_calc == gph->fcs ? "correct" : "WRONG");
if (gph->cmd)
DEBUGPC(DGPRS, "CMD=%u ", gph->cmd);
if (gph->data)
DEBUGPC(DGPRS, "DATA ");
DEBUGPC(DGPRS, "\n");
}
static int gprs_llc_hdr_rx(struct gprs_llc_hdr_parsed *gph,
struct gprs_llc_lle *lle)
{
switch (gph->cmd) {
case GPRS_LLC_SABM: /* Section 6.4.1.1 */
lle->v_sent = lle->v_ack = lle->v_recv = 0;
if (lle->state == GPRS_LLS_ASSIGNED_ADM) {
/* start re-establishment (8.7.1) */
}
lle->state = GPRS_LLS_REMOTE_EST;
/* FIXME: Send UA */
lle->state = GPRS_LLS_ABM;
/* FIXME: process data */
break;
case GPRS_LLC_DISC: /* Section 6.4.1.2 */
/* FIXME: Send UA */
/* terminate ABM */
lle->state = GPRS_LLS_ASSIGNED_ADM;
break;
case GPRS_LLC_UA: /* Section 6.4.1.3 */
if (lle->state == GPRS_LLS_LOCAL_EST)
lle->state = GPRS_LLS_ABM;
break;
case GPRS_LLC_DM: /* Section 6.4.1.4: ABM cannot be performed */
if (lle->state == GPRS_LLS_LOCAL_EST)
lle->state = GPRS_LLS_ASSIGNED_ADM;
break;
case GPRS_LLC_FRMR: /* Section 6.4.1.5 */
break;
case GPRS_LLC_XID: /* Section 6.4.1.6 */
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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/* FIXME: implement XID negotiation using SNDCP */
{
struct msgb *resp;
uint8_t *xid;
resp = msgb_alloc_headroom(4096, 1024, "LLC_XID");
xid = msgb_put(resp, gph->data_len);
memcpy(xid, gph->data, gph->data_len);
gprs_llc_tx_xid(lle, resp);
}
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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break;
}
return 0;
}
/* parse a GPRS LLC header, also check for invalid frames */
static int gprs_llc_hdr_parse(struct gprs_llc_hdr_parsed *ghp,
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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const uint8_t *llc_hdr, int len)
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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{
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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uint8_t *ctrl = llc_hdr+1;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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int is_sack = 0;
unsigned int crc_length;
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
2010-05-02 09:26:34 +00:00
uint32_t fcs_calc;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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if (len <= CRC24_LENGTH)
return -EIO;
crc_length = len - CRC24_LENGTH;
ghp->ack_req = 0;
/* Section 5.5: FCS */
ghp->fcs = *(llc_hdr + len - 3);
ghp->fcs |= *(llc_hdr + len - 2) << 8;
ghp->fcs |= *(llc_hdr + len - 1) << 16;
/* Section 6.2.1: invalid PD field */
if (llc_hdr[0] & 0x80)
return -EIO;
/* This only works for the MS->SGSN direction */
if (llc_hdr[0] & 0x40)
ghp->is_cmd = 0;
else
ghp->is_cmd = 1;
ghp->sapi = llc_hdr[0] & 0xf;
/* Section 6.2.3: check for reserved SAPI */
switch (ghp->sapi) {
case 0:
case 4:
case 6:
case 0xa:
case 0xc:
case 0xd:
case 0xf:
return -EINVAL;
}
if ((ctrl[0] & 0x80) == 0) {
/* I (Information transfer + Supervisory) format */
[gprs] Use stdint.h types (uintXX_t instead of u_intXX_t) libosmocore already uses them, it's time (at least for new code) in openbsc to do the same.
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uint8_t k;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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ghp->data = ctrl + 3;
if (ctrl[0] & 0x40)
ghp->ack_req = 1;
ghp->seq_tx = (ctrl[0] & 0x1f) << 4;
ghp->seq_tx |= (ctrl[1] >> 4);
ghp->seq_rx = (ctrl[1] & 0x7) << 6;
ghp->seq_rx |= (ctrl[2] >> 2);
switch (ctrl[2] & 0x03) {
case 0:
ghp->cmd = GPRS_LLC_RR;
break;
case 1:
ghp->cmd = GPRS_LLC_ACK;
break;
case 2:
ghp->cmd = GPRS_LLC_RNR;
break;
case 3:
ghp->cmd = GPRS_LLC_SACK;
k = ctrl[3] & 0x1f;
ghp->data += 1 + k;
break;
}
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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ghp->data_len = (llc_hdr + len - 3) - ghp->data;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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} else if ((ctrl[0] & 0xc0) == 0x80) {
/* S (Supervisory) format */
ghp->data = NULL;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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ghp->data_len = 0;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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if (ctrl[0] & 0x20)
ghp->ack_req = 1;
ghp->seq_rx = (ctrl[0] & 0x7) << 6;
ghp->seq_rx |= (ctrl[1] >> 2);
switch (ctrl[1] & 0x03) {
case 0:
ghp->cmd = GPRS_LLC_RR;
break;
case 1:
ghp->cmd = GPRS_LLC_ACK;
break;
case 2:
ghp->cmd = GPRS_LLC_RNR;
break;
case 3:
ghp->cmd = GPRS_LLC_SACK;
break;
}
} else if ((ctrl[0] & 0xe0) == 0xc0) {
/* UI (Unconfirmed Inforamtion) format */
ghp->data = ctrl + 2;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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ghp->data_len = (llc_hdr + len - 3) - ghp->data;
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ghp->seq_tx = (ctrl[0] & 0x7) << 6;
ghp->seq_tx |= (ctrl[1] >> 2);
if (ctrl[1] & 0x02) {
ghp->is_encrypted = 1;
/* FIXME: encryption */
}
if (ctrl[1] & 0x01) {
/* FCS over hdr + all inf fields */
} else {
/* FCS over hdr + N202 octets (4) */
if (crc_length > UI_HDR_LEN + N202)
crc_length = UI_HDR_LEN + N202;
}
} else {
/* U (Unnumbered) format: 1 1 1 P/F M4 M3 M2 M1 */
ghp->data = NULL;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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ghp->data_len = 0;
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switch (ctrl[0] & 0xf) {
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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case GPRS_LLC_U_NULL_CMD:
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ghp->cmd = GPRS_LLC_NULL;
break;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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case GPRS_LLC_U_DM_RESP:
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ghp->cmd = GPRS_LLC_DM;
break;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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case GPRS_LLC_U_DISC_CMD:
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ghp->cmd = GPRS_LLC_DISC;
break;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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case GPRS_LLC_U_UA_RESP:
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ghp->cmd = GPRS_LLC_UA;
break;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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case GPRS_LLC_U_SABM_CMD:
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ghp->cmd = GPRS_LLC_SABM;
break;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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case GPRS_LLC_U_FRMR_RESP:
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ghp->cmd = GPRS_LLC_FRMR;
break;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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case GPRS_LLC_U_XID:
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ghp->cmd = GPRS_LLC_XID;
[gprs] LLC: Echo back the XID parameters that the MS requested In order to finish PDP context activation and start the transfer of SNDCP N-PDUs, we simply confirm to the MS whatever XID parameters it requests. This of course has to be implemented with a proper XID handshake at some other point.
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ghp->data = ctrl + 1;
ghp->data_len = (llc_hdr + len - 3) - ghp->data;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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break;
default:
return -EIO;
}
}
/* calculate what FCS we expect */
ghp->fcs_calc = gprs_llc_fcs(llc_hdr, crc_length);
/* FIXME: parse sack frame */
}
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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/* receive an incoming LLC PDU (BSSGP-UL-UNITDATA-IND, 7.2.4.2) */
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int gprs_llc_rcvmsg(struct msgb *msg, struct tlv_parsed *tv)
{
[gprs] Ensure msgb->l3h points to Layer3 (04.08) In the old code l3h = BSSGP, l4h = LLC, cb[gmmh] = 04.08 Now, this has been changed to cb[bssgph] = BSSGP, cb[llch] = LLC, l3h = 04.08 This way, GSM general 04.08 and GPRS 04.08 code can expect a GSM 04.08 header at msgb->l3h
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struct bssgp_ud_hdr *udh = (struct bssgp_ud_hdr *) msgb_bssgph(msg);
gprs: Update gprs-sgsn branch to use new msgb->cb layout The explicit 'tlli, gmmh' members of struct msgb are gone from current libosmocore and have been replaced by the more generic 'control buffer' mechanism.
2010-04-30 14:33:12 +00:00
struct gprs_llc_hdr *lh = msgb_llch(msg);
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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struct gprs_llc_hdr_parsed llhp;
[gprs] LLC: API to send XID responses to XID commands
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struct gprs_llc_lle *lle;
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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int rc = 0;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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[gprs] pass BSSGP UL-UNITDATA Cell ID up into GMM layer BSSGP stores a pointer to the Cell Identifier IE in msgb->cb, which is later used by the GMM layer to identify the cell that has sent a given message. This now also means that the gsm_04_08_gprs.c code is free of any legacy references to msg->trx or struct gsm_bts.
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/* Identifiers from DOWN: NSEI, BVCI, TLLI */
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rc = gprs_llc_hdr_parse(&llhp, lh, TLVP_LEN(tv, BSSGP_IE_LLC_PDU));
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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/* FIXME */
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gprs_llc_hdr_dump(&llhp);
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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/* find the LLC Entity for this TLLI+SAPI tuple */
lle = lle_by_tlli_sapi(msgb_tlli(msg), llhp.sapi);
/* allocate a new LLE if needed */
if (!lle)
lle = lle_alloc(msgb_tlli(msg), llhp.sapi);
[gprs] LLC: API to send XID responses to XID commands
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/* Update LLE's (BVCI, NSEI) tuple */
lle->bvci = msgb_bvci(msg);
lle->nsei = msgb_nsei(msg);
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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rc = gprs_llc_hdr_rx(&llhp, lle);
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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/* FIXME */
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if (llhp.data) {
gprs: Update gprs-sgsn branch to use new msgb->cb layout The explicit 'tlli, gmmh' members of struct msgb are gone from current libosmocore and have been replaced by the more generic 'control buffer' mechanism.
2010-04-30 14:33:12 +00:00
msgb_gmmh(msg) = llhp.data;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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switch (llhp.sapi) {
case GPRS_SAPI_GMM:
rc = gsm0408_gprs_rcvmsg(msg);
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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break;
case GPRS_SAPI_TOM2:
case GPRS_SAPI_TOM8:
/* FIXME */
case GPRS_SAPI_SNDCP3:
case GPRS_SAPI_SNDCP5:
case GPRS_SAPI_SNDCP9:
case GPRS_SAPI_SNDCP11:
/* FIXME */
case GPRS_SAPI_SMS:
/* FIXME */
default:
LOGP(DGPRS, LOGL_NOTICE, "Unsupported SAPI %u\n", llhp.sapi);
rc = -EINVAL;
break;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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}
}
[gprs] LLC: Introduce the allocation and lookup of LLC Entities (LLE)
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return rc;
Create new 'gprs-sgsn' branch on top of 'gprs-conf' This branch contains the partial SGSN/GGSN implementation that was originally developed as part of the gprs branch.
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}