371 lines
10 KiB
C
371 lines
10 KiB
C
/*
|
|
* OsmoGGSN - Gateway GPRS Support Node
|
|
* Copyright (C) 2002, 2003, 2004 Mondru AB.
|
|
* Copyright (C) 2017 Harald Welte <laforge@gnumonks.org>
|
|
*
|
|
* The contents of this file may be used under the terms of the GNU
|
|
* General Public License Version 2, provided that the above copyright
|
|
* notice and this permission notice is included in all copies or
|
|
* substantial portions of the software.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* pdp.c:
|
|
*
|
|
*/
|
|
|
|
#include <../config.h>
|
|
|
|
#include <osmocom/core/logging.h>
|
|
|
|
#ifdef HAVE_STDINT_H
|
|
#include <stdint.h>
|
|
#endif
|
|
|
|
#include <stdio.h>
|
|
#include <sys/types.h>
|
|
#include <netinet/in.h>
|
|
#include <string.h>
|
|
#include <inttypes.h>
|
|
#include "pdp.h"
|
|
#include "gtp.h"
|
|
#include "lookupa.h"
|
|
#include "queue.h"
|
|
|
|
/* ***********************************************************
|
|
* Functions related to PDP storage
|
|
*
|
|
* Lifecycle
|
|
* For a GGSN pdp context life begins with the reception of a
|
|
* create pdp context request. It normally ends with the reception
|
|
* of a delete pdp context request, but will also end with the
|
|
* reception of an error indication message.
|
|
* Provisions should probably be made for terminating pdp contexts
|
|
* based on either idle timeout, or by sending downlink probe
|
|
* messages (ping?) to see if the MS is still responding.
|
|
*
|
|
* For an SGSN pdp context life begins with the application just
|
|
* before sending off a create pdp context request. It normally
|
|
* ends when a delete pdp context response message is received
|
|
* from the GGSN, but should also end when with the reception of
|
|
* an error indication message.
|
|
*
|
|
*
|
|
* HASH Tables
|
|
*
|
|
* Downlink packets received in the GGSN are identified only by their
|
|
* network interface together with their destination IP address (Two
|
|
* network interfaces can use the same private IP address). Each IMSI
|
|
* (mobile station) can have several PDP contexts using the same IP
|
|
* address. In this case the traffic flow template (TFT) is used to
|
|
* determine the correct PDP context for a particular IMSI. Also it
|
|
* should be possible for each PDP context to use several IP adresses
|
|
* For fixed wireless access a mobile station might need a full class
|
|
* C network. Even in the case of several IP adresses the PDP context
|
|
* should be determined on the basis of the network IP address.
|
|
* Thus we need a hash table based on network interface + IP address.
|
|
*
|
|
* Uplink packets are for GTP0 identified by their IMSI and NSAPI, which
|
|
* is collectively called the tunnel identifier. There is also a 16 bit
|
|
* flow label that can be used for identification of uplink packets. This
|
|
* however is quite useless as it limits the number of contexts to 65536.
|
|
* For GTP1 uplink packets are identified by a Tunnel Endpoint Identifier
|
|
* (32 bit), or in some cases by the combination of IMSI and NSAPI.
|
|
* For GTP1 delete context requests there is a need to find the PDP
|
|
* contexts with the same IP address. This however can be done by using
|
|
* the IP hash table.
|
|
* Thus we need a hash table based on TID (IMSI and NSAPI). The TEID will
|
|
* be used for directly addressing the PDP context.
|
|
|
|
* pdp_newpdp
|
|
* Gives you a pdp context with no hash references In some way
|
|
* this should have a limited lifetime.
|
|
*
|
|
* pdp_freepdp
|
|
* Frees a context that was previously allocated with
|
|
* pdp_newpdp
|
|
*
|
|
*
|
|
* pdp_getpdpIP
|
|
* An incoming IP packet is uniquely identified by a pointer
|
|
* to a network connection (void *) and an IP address
|
|
* (struct in_addr)
|
|
*
|
|
* pdp_getpdpGTP
|
|
* An incoming GTP packet is uniquely identified by a the
|
|
* TID (imsi + nsapi (8 octets)) in or by the Flow Label
|
|
* (2 octets) in gtp0 or by the Tunnel Endpoint Identifier
|
|
* (4 octets) in gtp1.
|
|
*
|
|
* This leads to an architecture where the receiving GSN
|
|
* chooses a Flow Label or a Tunnel Endpoint Identifier
|
|
* when the connection is setup.
|
|
* Thus no hash table is needed for GTP lookups.
|
|
*
|
|
*************************************************************/
|
|
|
|
static struct gsn_t *g_gsn;
|
|
|
|
int pdp_init(struct gsn_t *gsn)
|
|
{
|
|
if (!g_gsn) {
|
|
g_gsn = gsn;
|
|
} else {
|
|
LOGP(DLGTP, LOGL_FATAL, "This interface is depreacted and doesn't support multiple GGSN!");
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int pdp_newpdp(struct pdp_t **pdp, uint64_t imsi, uint8_t nsapi,
|
|
struct pdp_t *pdp_old)
|
|
{
|
|
return gtp_pdp_newpdp(g_gsn, pdp, imsi, nsapi, pdp_old);
|
|
}
|
|
|
|
int gtp_pdp_newpdp(struct gsn_t *gsn, struct pdp_t **pdp, uint64_t imsi, uint8_t nsapi,
|
|
struct pdp_t *pdp_old)
|
|
{
|
|
struct pdp_t *pdpa = gsn->pdpa;
|
|
int n;
|
|
for (n = 0; n < PDP_MAX; n++) { /* TODO: Need to do better than linear search */
|
|
if (pdpa[n].inuse == 0) {
|
|
*pdp = &pdpa[n];
|
|
if (NULL != pdp_old)
|
|
memcpy(*pdp, pdp_old, sizeof(struct pdp_t));
|
|
else
|
|
memset(*pdp, 0, sizeof(struct pdp_t));
|
|
(*pdp)->inuse = 1;
|
|
(*pdp)->gsn = gsn;
|
|
(*pdp)->imsi = imsi;
|
|
(*pdp)->nsapi = nsapi;
|
|
(*pdp)->fllc = (uint16_t) n + 1;
|
|
(*pdp)->fllu = (uint16_t) n + 1;
|
|
(*pdp)->teid_own = (uint32_t) n + 1;
|
|
if (!(*pdp)->secondary)
|
|
(*pdp)->teic_own = (uint32_t) n + 1;
|
|
pdp_tidset(*pdp, pdp_gettid(imsi, nsapi));
|
|
|
|
/* Insert reference in primary context */
|
|
if (((*pdp)->teic_own > 0)
|
|
&& ((*pdp)->teic_own <= PDP_MAX)) {
|
|
pdpa[(*pdp)->teic_own -
|
|
1].secondary_tei[(*pdp)->nsapi & 0x0f] =
|
|
(*pdp)->teid_own;
|
|
}
|
|
/* Default: Generate G-PDU sequence numbers on Tx */
|
|
(*pdp)->tx_gpdu_seq = true;
|
|
INIT_LLIST_HEAD(&(*pdp)->qmsg_list_req);
|
|
return 0;
|
|
}
|
|
}
|
|
return EOF; /* No more available */
|
|
}
|
|
|
|
int pdp_freepdp(struct pdp_t *pdp)
|
|
{
|
|
struct qmsg_t *qmsg, *qmsg2;
|
|
struct pdp_t *pdpa = pdp->gsn->pdpa;
|
|
int rc;
|
|
|
|
/* Remove all enqueued messages belonging to this pdp from req tx transmit
|
|
queue. queue_freemsg will call llist_del(). */
|
|
llist_for_each_entry_safe(qmsg, qmsg2, &pdp->qmsg_list_req, entry) {
|
|
if ((rc = queue_freemsg(pdp->gsn->queue_req, qmsg)))
|
|
LOGP(DLGTP, LOGL_ERROR,
|
|
"Failed freeing qmsg from qmsg_list_req during pdp_freepdp()! %d\n", rc);
|
|
}
|
|
|
|
pdp_tiddel(pdp);
|
|
|
|
/* Remove any references in primary context */
|
|
if ((pdp->secondary) && (pdp->teic_own > 0)
|
|
&& (pdp->teic_own <= PDP_MAX)) {
|
|
pdpa[pdp->teic_own - 1].secondary_tei[pdp->nsapi & 0x0f] = 0;
|
|
}
|
|
|
|
memset(pdp, 0, sizeof(struct pdp_t));
|
|
return 0;
|
|
}
|
|
|
|
int pdp_getpdp(struct pdp_t **pdp)
|
|
{
|
|
*pdp = &g_gsn->pdpa[0];
|
|
return 0;
|
|
}
|
|
|
|
int pdp_getgtp0(struct pdp_t **pdp, uint16_t fl)
|
|
{
|
|
return gtp_pdp_getgtp0(g_gsn, pdp, fl);
|
|
}
|
|
|
|
|
|
int gtp_pdp_getgtp0(struct gsn_t *gsn, struct pdp_t **pdp, uint16_t fl)
|
|
{
|
|
struct pdp_t *pdpa = gsn->pdpa;
|
|
|
|
if ((fl > PDP_MAX) || (fl < 1)) {
|
|
return EOF; /* Not found */
|
|
} else {
|
|
*pdp = &pdpa[fl - 1];
|
|
if ((*pdp)->inuse)
|
|
return 0;
|
|
else
|
|
return EOF;
|
|
/* Context exists. We do no further validity checking. */
|
|
}
|
|
}
|
|
|
|
int pdp_getgtp1(struct pdp_t **pdp, uint32_t tei)
|
|
{
|
|
return gtp_pdp_getgtp1(g_gsn, pdp, tei);
|
|
}
|
|
|
|
int gtp_pdp_getgtp1(struct gsn_t *gsn, struct pdp_t **pdp, uint32_t tei)
|
|
{
|
|
struct pdp_t *pdpa = gsn->pdpa;
|
|
|
|
if ((tei > PDP_MAX) || (tei < 1)) {
|
|
return EOF; /* Not found */
|
|
} else {
|
|
*pdp = &pdpa[tei - 1];
|
|
if ((*pdp)->inuse)
|
|
return 0;
|
|
else
|
|
return EOF;
|
|
/* Context exists. We do no further validity checking. */
|
|
}
|
|
}
|
|
|
|
/* get a PDP based on the *peer* address + TEI-Data. Used for matching inbound Error Ind */
|
|
int pdp_getgtp1_peer_d(struct pdp_t **pdp, const struct sockaddr_in *peer, uint32_t teid_gn)
|
|
{
|
|
return gtp_pdp_getgtp1_peer_d(g_gsn, pdp, peer, teid_gn);
|
|
}
|
|
|
|
int gtp_pdp_getgtp1_peer_d(struct gsn_t *gsn, struct pdp_t **pdp, const struct sockaddr_in *peer, uint32_t teid_gn)
|
|
{
|
|
struct pdp_t *pdpa = gsn->pdpa;
|
|
unsigned int i;
|
|
|
|
/* this is O(n) but we don't have (nor want) another hash... */
|
|
for (i = 0; i < PDP_MAX; i++) {
|
|
struct pdp_t *candidate = &pdpa[i];
|
|
if (candidate->inuse && candidate->teid_gn == teid_gn &&
|
|
candidate->gsnru.l == sizeof(peer->sin_addr) &&
|
|
!memcmp(&peer->sin_addr, candidate->gsnru.v, sizeof(peer->sin_addr))) {
|
|
*pdp = &pdpa[i];
|
|
return 0;
|
|
}
|
|
}
|
|
return EOF;
|
|
}
|
|
|
|
int pdp_tidhash(uint64_t tid)
|
|
{
|
|
return (lookup(&tid, sizeof(tid), 0) % PDP_MAX);
|
|
}
|
|
|
|
int pdp_tidset(struct pdp_t *pdp, uint64_t tid)
|
|
{
|
|
struct pdp_t **hashtid = pdp->gsn->hashtid;
|
|
int hash = pdp_tidhash(tid);
|
|
struct pdp_t *pdp2;
|
|
struct pdp_t *pdp_prev = NULL;
|
|
DEBUGP(DLGTP, "Begin pdp_tidset tid = %"PRIx64"\n", tid);
|
|
pdp->tidnext = NULL;
|
|
pdp->tid = tid;
|
|
for (pdp2 = hashtid[hash]; pdp2; pdp2 = pdp2->tidnext)
|
|
pdp_prev = pdp2;
|
|
if (!pdp_prev)
|
|
hashtid[hash] = pdp;
|
|
else
|
|
pdp_prev->tidnext = pdp;
|
|
DEBUGP(DLGTP, "End pdp_tidset\n");
|
|
return 0;
|
|
}
|
|
|
|
int pdp_tiddel(struct pdp_t *pdp)
|
|
{
|
|
struct pdp_t **hashtid = pdp->gsn->hashtid;
|
|
int hash = pdp_tidhash(pdp->tid);
|
|
struct pdp_t *pdp2;
|
|
struct pdp_t *pdp_prev = NULL;
|
|
DEBUGP(DLGTP, "Begin pdp_tiddel tid = %"PRIx64"\n", pdp->tid);
|
|
for (pdp2 = hashtid[hash]; pdp2; pdp2 = pdp2->tidnext) {
|
|
if (pdp2 == pdp) {
|
|
if (!pdp_prev)
|
|
hashtid[hash] = pdp2->tidnext;
|
|
else
|
|
pdp_prev->tidnext = pdp2->tidnext;
|
|
DEBUGP(DLGTP, "End pdp_tiddel: PDP found\n");
|
|
return 0;
|
|
}
|
|
pdp_prev = pdp2;
|
|
}
|
|
DEBUGP(DLGTP, "End pdp_tiddel: PDP not found\n");
|
|
return EOF; /* End of linked list and not found */
|
|
}
|
|
|
|
int pdp_tidget(struct pdp_t **pdp, uint64_t tid)
|
|
{
|
|
return gtp_pdp_tidget(g_gsn, pdp, tid);
|
|
}
|
|
|
|
int gtp_pdp_tidget(struct gsn_t *gsn, struct pdp_t **pdp, uint64_t tid)
|
|
{
|
|
struct pdp_t **hashtid = gsn->hashtid;
|
|
int hash = pdp_tidhash(tid);
|
|
struct pdp_t *pdp2;
|
|
DEBUGP(DLGTP, "Begin pdp_tidget tid = %"PRIx64"\n", tid);
|
|
for (pdp2 = hashtid[hash]; pdp2; pdp2 = pdp2->tidnext) {
|
|
if (pdp2->tid == tid) {
|
|
*pdp = pdp2;
|
|
DEBUGP(DLGTP, "Begin pdp_tidget. Found\n");
|
|
return 0;
|
|
}
|
|
}
|
|
DEBUGP(DLGTP, "Begin pdp_tidget. Not found\n");
|
|
return EOF; /* End of linked list and not found */
|
|
}
|
|
|
|
int pdp_getimsi(struct pdp_t **pdp, uint64_t imsi, uint8_t nsapi)
|
|
{
|
|
return gtp_pdp_getimsi(g_gsn, pdp, imsi, nsapi);
|
|
}
|
|
|
|
int gtp_pdp_getimsi(struct gsn_t *gsn, struct pdp_t **pdp, uint64_t imsi, uint8_t nsapi)
|
|
{
|
|
return gtp_pdp_tidget(gsn, pdp, pdp_gettid(imsi, nsapi));
|
|
}
|
|
|
|
|
|
/* Various conversion functions */
|
|
|
|
uint64_t pdp_gettid(uint64_t imsi, uint8_t nsapi)
|
|
{
|
|
return (imsi & 0x0fffffffffffffffull) + ((uint64_t) nsapi << 60);
|
|
}
|
|
|
|
void pdp_set_imsi_nsapi(struct pdp_t *pdp, uint64_t teid)
|
|
{
|
|
pdp->imsi = teid & 0x0fffffffffffffffull;
|
|
pdp->nsapi = (teid & 0xf000000000000000ull) >> 60;
|
|
}
|
|
|
|
/* Count amount of secondary PDP contexts linked to this primary PDP context
|
|
* (itself included). Must be called on a primary PDP context. */
|
|
unsigned int pdp_count_secondary(const struct pdp_t *pdp)
|
|
{
|
|
unsigned int n;
|
|
unsigned int count = 0;
|
|
OSMO_ASSERT(!pdp->secondary);
|
|
|
|
for (n = 0; n < PDP_MAXNSAPI; n++)
|
|
if (pdp->secondary_tei[n])
|
|
count++;
|
|
return count;
|
|
}
|