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freebsd/sys/netgraph/ng_lmi.c
Julian Elischer 069154d55f Rewrite of netgraph to start getting ready for SMP.
This version is functional and is aproaching solid..
notice I said APROACHING. There are many node types I cannot test
I have tested: echo hole ppp socket vjc iface tee bpf async tty
The rest compile and "Look" right.  More changes to follow.
DEBUGGING is enabled in this code to help if people have problems.
2001-01-06 00:46:47 +00:00

1090 lines
28 KiB
C

/*
* ng_lmi.c
*
* Copyright (c) 1996-1999 Whistle Communications, Inc.
* All rights reserved.
*
* Subject to the following obligations and disclaimer of warranty, use and
* redistribution of this software, in source or object code forms, with or
* without modifications are expressly permitted by Whistle Communications;
* provided, however, that:
* 1. Any and all reproductions of the source or object code must include the
* copyright notice above and the following disclaimer of warranties; and
* 2. No rights are granted, in any manner or form, to use Whistle
* Communications, Inc. trademarks, including the mark "WHISTLE
* COMMUNICATIONS" on advertising, endorsements, or otherwise except as
* such appears in the above copyright notice or in the software.
*
* THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
* TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
* REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
* INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
* WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
* REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
* SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
* IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
* RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
* WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
* PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* Author: Julian Elischer <julian@freebsd.org>
*
* $FreeBSD$
* $Whistle: ng_lmi.c,v 1.38 1999/11/01 09:24:52 julian Exp $
*/
/*
* This node performs the frame relay LMI protocol. It knows how
* to do ITU Annex A, ANSI Annex D, and "Group-of-Four" variants
* of the protocol.
*
* A specific protocol can be forced by connecting the corresponding
* hook to DLCI 0 or 1023 (as appropriate) of a frame relay link.
*
* Alternately, this node can do auto-detection of the LMI protocol
* by connecting hook "auto0" to DLCI 0 and "auto1023" to DLCI 1023.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/syslog.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_lmi.h>
/*
* Human readable names for LMI
*/
#define NAME_ANNEXA NG_LMI_HOOK_ANNEXA
#define NAME_ANNEXD NG_LMI_HOOK_ANNEXD
#define NAME_GROUP4 NG_LMI_HOOK_GROUPOF4
#define NAME_NONE "None"
#define MAX_DLCIS 128
#define MAXDLCI 1023
/*
* DLCI states
*/
#define DLCI_NULL 0
#define DLCI_UP 1
#define DLCI_DOWN 2
/*
* Any received LMI frame should be at least this long
*/
#define LMI_MIN_LENGTH 8 /* XXX verify */
/*
* Netgraph node methods and type descriptor
*/
static ng_constructor_t nglmi_constructor;
static ng_rcvmsg_t nglmi_rcvmsg;
static ng_shutdown_t nglmi_shutdown;
static ng_newhook_t nglmi_newhook;
static ng_rcvdata_t nglmi_rcvdata;
static ng_disconnect_t nglmi_disconnect;
static int nglmi_checkdata(hook_p hook, struct mbuf *m);
static struct ng_type typestruct = {
NG_ABI_VERSION,
NG_LMI_NODE_TYPE,
NULL,
nglmi_constructor,
nglmi_rcvmsg,
nglmi_shutdown,
nglmi_newhook,
NULL,
NULL,
nglmi_rcvdata,
nglmi_disconnect,
NULL
};
NETGRAPH_INIT(lmi, &typestruct);
/*
* Info and status per node
*/
struct nglmi_softc {
node_p node; /* netgraph node */
int flags; /* state */
int poll_count; /* the count of times for autolmi */
int poll_state; /* state of auto detect machine */
u_char remote_seq; /* sequence number the remote sent */
u_char local_seq; /* last sequence number we sent */
u_char protoID; /* 9 for group of 4, 8 otherwise */
u_long seq_retries; /* sent this how many time so far */
struct callout_handle handle; /* see timeout(9) */
int liv_per_full;
int liv_rate;
int livs;
int need_full;
hook_p lmi_channel; /* whatever we ended up using */
hook_p lmi_annexA;
hook_p lmi_annexD;
hook_p lmi_group4;
hook_p lmi_channel0; /* auto-detect on DLCI 0 */
hook_p lmi_channel1023;/* auto-detect on DLCI 1023 */
char *protoname; /* cache protocol name */
u_char dlci_state[MAXDLCI + 1];
int invalidx; /* next dlci's to invalidate */
};
typedef struct nglmi_softc *sc_p;
/*
* Other internal functions
*/
static void LMI_ticker(void *arg);
static void nglmi_startup_fixed(sc_p sc, hook_p hook);
static void nglmi_startup_auto(sc_p sc);
static void nglmi_startup(sc_p sc);
static void nglmi_inquire(sc_p sc, int full);
static void ngauto_state_machine(sc_p sc);
/*
* Values for 'flags' field
* NB: the SCF_CONNECTED flag is set if and only if the timer is running.
*/
#define SCF_CONNECTED 0x01 /* connected to something */
#define SCF_AUTO 0x02 /* we are auto-detecting */
#define SCF_FIXED 0x04 /* we are fixed from the start */
#define SCF_LMITYPE 0x18 /* mask for determining Annex mode */
#define SCF_NOLMI 0x00 /* no LMI type selected yet */
#define SCF_ANNEX_A 0x08 /* running annex A mode */
#define SCF_ANNEX_D 0x10 /* running annex D mode */
#define SCF_GROUP4 0x18 /* running group of 4 */
#define SETLMITYPE(sc, annex) \
do { \
(sc)->flags &= ~SCF_LMITYPE; \
(sc)->flags |= (annex); \
} while (0)
#define NOPROTO(sc) (((sc)->flags & SCF_LMITYPE) == SCF_NOLMI)
#define ANNEXA(sc) (((sc)->flags & SCF_LMITYPE) == SCF_ANNEX_A)
#define ANNEXD(sc) (((sc)->flags & SCF_LMITYPE) == SCF_ANNEX_D)
#define GROUP4(sc) (((sc)->flags & SCF_LMITYPE) == SCF_GROUP4)
#define LMIPOLLSIZE 3
#define LMI_PATIENCE 8 /* declare all DLCI DOWN after N LMI failures */
/*
* Node constructor
*/
static int
nglmi_constructor(node_p node)
{
sc_p sc;
MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (sc == NULL)
return (ENOMEM);
callout_handle_init(&sc->handle);
node->private = sc;
sc->protoname = NAME_NONE;
sc->node = node;
sc->liv_per_full = NG_LMI_SEQ_PER_FULL; /* make this dynamic */
sc->liv_rate = NG_LMI_KEEPALIVE_RATE;
return (0);
}
/*
* The LMI channel has a private pointer which is the same as the
* node private pointer. The debug channel has a NULL private pointer.
*/
static int
nglmi_newhook(node_p node, hook_p hook, const char *name)
{
sc_p sc = node->private;
if (strcmp(name, NG_LMI_HOOK_DEBUG) == 0) {
hook->private = NULL;
return (0);
}
if (sc->flags & SCF_CONNECTED) {
/* already connected, return an error */
return (EINVAL);
}
if (strcmp(name, NG_LMI_HOOK_ANNEXA) == 0) {
sc->lmi_annexA = hook;
hook->private = node->private;
sc->protoID = 8;
SETLMITYPE(sc, SCF_ANNEX_A);
sc->protoname = NAME_ANNEXA;
nglmi_startup_fixed(sc, hook);
} else if (strcmp(name, NG_LMI_HOOK_ANNEXD) == 0) {
sc->lmi_annexD = hook;
hook->private = node->private;
sc->protoID = 8;
SETLMITYPE(sc, SCF_ANNEX_D);
sc->protoname = NAME_ANNEXD;
nglmi_startup_fixed(sc, hook);
} else if (strcmp(name, NG_LMI_HOOK_GROUPOF4) == 0) {
sc->lmi_group4 = hook;
hook->private = node->private;
sc->protoID = 9;
SETLMITYPE(sc, SCF_GROUP4);
sc->protoname = NAME_GROUP4;
nglmi_startup_fixed(sc, hook);
} else if (strcmp(name, NG_LMI_HOOK_AUTO0) == 0) {
/* Note this, and if B is already installed, we're complete */
sc->lmi_channel0 = hook;
sc->protoname = NAME_NONE;
hook->private = node->private;
if (sc->lmi_channel1023)
nglmi_startup_auto(sc);
} else if (strcmp(name, NG_LMI_HOOK_AUTO1023) == 0) {
/* Note this, and if A is already installed, we're complete */
sc->lmi_channel1023 = hook;
sc->protoname = NAME_NONE;
hook->private = node->private;
if (sc->lmi_channel0)
nglmi_startup_auto(sc);
} else
return (EINVAL); /* unknown hook */
return (0);
}
/*
* We have just attached to a live (we hope) node.
* Fire out a LMI inquiry, and then start up the timers.
*/
static void
LMI_ticker(void *arg)
{
sc_p sc = arg;
int s = splnet();
if (sc->flags & SCF_AUTO) {
ngauto_state_machine(sc);
sc->handle = timeout(LMI_ticker, sc, NG_LMI_POLL_RATE * hz);
} else {
if (sc->livs++ >= sc->liv_per_full) {
nglmi_inquire(sc, 1);
/* sc->livs = 0; *//* do this when we get the answer! */
} else {
nglmi_inquire(sc, 0);
}
sc->handle = timeout(LMI_ticker, sc, sc->liv_rate * hz);
}
splx(s);
}
static void
nglmi_startup_fixed(sc_p sc, hook_p hook)
{
sc->flags |= (SCF_FIXED | SCF_CONNECTED);
sc->lmi_channel = hook;
nglmi_startup(sc);
}
static void
nglmi_startup_auto(sc_p sc)
{
sc->flags |= (SCF_AUTO | SCF_CONNECTED);
sc->poll_state = 0; /* reset state machine */
sc->poll_count = 0;
nglmi_startup(sc);
}
static void
nglmi_startup(sc_p sc)
{
sc->remote_seq = 0;
sc->local_seq = 1;
sc->seq_retries = 0;
sc->livs = sc->liv_per_full - 1;
/* start off the ticker in 1 sec */
sc->handle = timeout(LMI_ticker, sc, hz);
}
#define META_PAD 16
static void
nglmi_inquire(sc_p sc, int full)
{
struct mbuf *m;
char *cptr, *start;
int error;
meta_p meta = NULL;
if (sc->lmi_channel == NULL)
return;
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL) {
log(LOG_ERR, "nglmi: unable to start up LMI processing\n");
return;
}
m->m_pkthdr.rcvif = NULL;
/* Allocate a meta struct (and leave some slop for options to be
* added by other modules). */
/* MALLOC(meta, meta_p, sizeof( struct ng_meta) + META_PAD,
* M_NETGRAPH, M_NOWAIT); */
MALLOC(meta, meta_p, sizeof(*meta) + META_PAD, M_NETGRAPH, M_NOWAIT);
if (meta != NULL) { /* if it failed, well, it was optional anyhow */
meta->used_len = (u_short) sizeof(struct ng_meta);
meta->allocated_len
= (u_short) sizeof(struct ng_meta) + META_PAD;
meta->flags = 0;
meta->priority = NG_LMI_LMI_PRIORITY;
meta->discardability = -1;
}
m->m_data += 4; /* leave some room for a header */
cptr = start = mtod(m, char *);
/* add in the header for an LMI inquiry. */
*cptr++ = 0x03; /* UI frame */
if (GROUP4(sc))
*cptr++ = 0x09; /* proto discriminator */
else
*cptr++ = 0x08; /* proto discriminator */
*cptr++ = 0x00; /* call reference */
*cptr++ = 0x75; /* inquiry */
/* If we are Annex-D, there is this extra thing.. */
if (ANNEXD(sc))
*cptr++ = 0x95; /* ??? */
/* Add a request type */
if (ANNEXA(sc))
*cptr++ = 0x51; /* report type */
else
*cptr++ = 0x01; /* report type */
*cptr++ = 0x01; /* size = 1 */
if (full)
*cptr++ = 0x00; /* full */
else
*cptr++ = 0x01; /* partial */
/* Add a link verification IE */
if (ANNEXA(sc))
*cptr++ = 0x53; /* verification IE */
else
*cptr++ = 0x03; /* verification IE */
*cptr++ = 0x02; /* 2 extra bytes */
*cptr++ = sc->local_seq;
*cptr++ = sc->remote_seq;
sc->seq_retries++;
/* Send it */
m->m_len = m->m_pkthdr.len = cptr - start;
NG_SEND_DATA(error, sc->lmi_channel, m, meta);
/* If we've been sending requests for long enough, and there has
* been no response, then mark as DOWN, any DLCIs that are UP. */
if (sc->seq_retries == LMI_PATIENCE) {
int count;
for (count = 0; count < MAXDLCI; count++)
if (sc->dlci_state[count] == DLCI_UP)
sc->dlci_state[count] = DLCI_DOWN;
}
}
/*
* State machine for LMI auto-detect. The transitions are ordered
* to try the more likely possibilities first.
*/
static void
ngauto_state_machine(sc_p sc)
{
if ((sc->poll_count <= 0) || (sc->poll_count > LMIPOLLSIZE)) {
/* time to change states in the auto probe machine */
/* capture wild values of poll_count while we are at it */
sc->poll_count = LMIPOLLSIZE;
sc->poll_state++;
}
switch (sc->poll_state) {
case 7:
log(LOG_WARNING, "nglmi: no response from exchange\n");
default: /* capture bad states */
sc->poll_state = 1;
case 1:
sc->lmi_channel = sc->lmi_channel0;
SETLMITYPE(sc, SCF_ANNEX_D);
break;
case 2:
sc->lmi_channel = sc->lmi_channel1023;
SETLMITYPE(sc, SCF_ANNEX_D);
break;
case 3:
sc->lmi_channel = sc->lmi_channel0;
SETLMITYPE(sc, SCF_ANNEX_A);
break;
case 4:
sc->lmi_channel = sc->lmi_channel1023;
SETLMITYPE(sc, SCF_GROUP4);
break;
case 5:
sc->lmi_channel = sc->lmi_channel1023;
SETLMITYPE(sc, SCF_ANNEX_A);
break;
case 6:
sc->lmi_channel = sc->lmi_channel0;
SETLMITYPE(sc, SCF_GROUP4);
break;
}
/* send an inquirey encoded appropriatly */
nglmi_inquire(sc, 0);
sc->poll_count--;
}
/*
* Receive a netgraph control message.
*/
static int
nglmi_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
sc_p sc = node->private;
struct ng_mesg *resp = NULL;
int error = 0;
struct ng_mesg *msg;
NGI_GET_MSG(item, msg);
switch (msg->header.typecookie) {
case NGM_GENERIC_COOKIE:
switch (msg->header.cmd) {
case NGM_TEXT_STATUS:
{
char *arg;
int pos, count;
NG_MKRESPONSE(resp, msg, NG_TEXTRESPONSE, M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
arg = resp->data;
pos = sprintf(arg, "protocol %s ", sc->protoname);
if (sc->flags & SCF_FIXED)
pos += sprintf(arg + pos, "fixed\n");
else if (sc->flags & SCF_AUTO)
pos += sprintf(arg + pos, "auto-detecting\n");
else
pos += sprintf(arg + pos, "auto on dlci %d\n",
(sc->lmi_channel == sc->lmi_channel0) ?
0 : 1023);
pos += sprintf(arg + pos,
"keepalive period: %d seconds\n", sc->liv_rate);
pos += sprintf(arg + pos,
"unacknowledged keepalives: %ld\n",
sc->seq_retries);
for (count = 0;
((count <= MAXDLCI)
&& (pos < (NG_TEXTRESPONSE - 20)));
count++) {
if (sc->dlci_state[count]) {
pos += sprintf(arg + pos,
"dlci %d %s\n", count,
(sc->dlci_state[count]
== DLCI_UP) ? "up" : "down");
}
}
resp->header.arglen = pos + 1;
break;
}
default:
error = EINVAL;
break;
}
break;
case NGM_LMI_COOKIE:
switch (msg->header.cmd) {
case NGM_LMI_GET_STATUS:
{
struct nglmistat *stat;
int k;
NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
if (!resp) {
error = ENOMEM;
break;
}
stat = (struct nglmistat *) resp->data;
strncpy(stat->proto,
sc->protoname, sizeof(stat->proto) - 1);
strncpy(stat->hook,
sc->protoname, sizeof(stat->hook) - 1);
stat->autod = !!(sc->flags & SCF_AUTO);
stat->fixed = !!(sc->flags & SCF_FIXED);
for (k = 0; k <= MAXDLCI; k++) {
switch (sc->dlci_state[k]) {
case DLCI_UP:
stat->up[k / 8] |= (1 << (k % 8));
/* fall through */
case DLCI_DOWN:
stat->seen[k / 8] |= (1 << (k % 8));
break;
}
}
break;
}
default:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
#define STEPBY(stepsize) \
do { \
packetlen -= (stepsize); \
data += (stepsize); \
} while (0)
/*
* receive data, and use it to update our status.
* Anything coming in on the debug port is discarded.
*/
static int
nglmi_rcvdata(hook_p hook, item_p item)
{
sc_p sc = hook->node->private;
u_char *data;
unsigned short dlci;
u_short packetlen;
int resptype_seen = 0;
int seq_seen = 0;
struct mbuf *m;
NGI_GET_M(item, m);
NG_FREE_ITEM(item);
if (hook->private == NULL) {
goto drop;
}
packetlen = m->m_hdr.mh_len;
/* XXX what if it's more than 1 mbuf? */
if ((packetlen > MHLEN) && !(m->m_flags & M_EXT)) {
log(LOG_WARNING, "nglmi: packetlen (%d) too big\n", packetlen);
goto drop;
}
if (m->m_len < packetlen && (m = m_pullup(m, packetlen)) == NULL) {
log(LOG_WARNING,
"nglmi: m_pullup failed for %d bytes\n", packetlen);
return (0);
}
if (nglmi_checkdata(hook, m) == 0)
return (0);
/* pass the first 4 bytes (already checked in the nglmi_checkdata()) */
data = mtod(m, u_char *);
STEPBY(4);
/* Now check if there is a 'locking shift'. This is only seen in
* Annex D frames. don't bother checking, we already did that. Don't
* increment immediatly as it might not be there. */
if (ANNEXD(sc))
STEPBY(1);
/* If we get this far we should consider that it is a legitimate
* frame and we know what it is. */
if (sc->flags & SCF_AUTO) {
/* note the hook that this valid channel came from and drop
* out of auto probe mode. */
if (ANNEXA(sc))
sc->protoname = NAME_ANNEXA;
else if (ANNEXD(sc))
sc->protoname = NAME_ANNEXD;
else if (GROUP4(sc))
sc->protoname = NAME_GROUP4;
else {
log(LOG_ERR, "nglmi: No known type\n");
goto drop;
}
sc->lmi_channel = hook;
sc->flags &= ~SCF_AUTO;
log(LOG_INFO, "nglmi: auto-detected %s LMI on DLCI %d\n",
sc->protoname, hook == sc->lmi_channel0 ? 0 : 1023);
}
/* While there is more data in the status packet, keep processing
* status items. First make sure there is enough data for the
* segment descriptor's length field. */
while (packetlen >= 2) {
u_int segtype = data[0];
u_int segsize = data[1];
/* Now that we know how long it claims to be, make sure
* there is enough data for the next seg. */
if (packetlen < segsize + 2)
break;
switch (segtype) {
case 0x01:
case 0x51:
if (resptype_seen) {
log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
goto nextIE;
}
resptype_seen++;
/* The remote end tells us what kind of response
* this is. Only expect a type 0 or 1. if we are a
* full status, invalidate a few DLCIs just to see
* that they are still ok. */
if (segsize != 1)
goto nextIE;
switch (data[2]) {
case 1:
/* partial status, do no extra processing */
break;
case 0:
{
int count = 0;
int idx = sc->invalidx;
for (count = 0; count < 10; count++) {
if (idx > MAXDLCI)
idx = 0;
if (sc->dlci_state[idx] == DLCI_UP)
sc->dlci_state[idx] = DLCI_DOWN;
idx++;
}
sc->invalidx = idx;
/* we got and we wanted one. relax
* now.. but don't reset to 0 if it
* was unrequested. */
if (sc->livs > sc->liv_per_full)
sc->livs = 0;
break;
}
}
break;
case 0x03:
case 0x53:
/* The remote tells us what it thinks the sequence
* numbers are. If it's not size 2, it must be a
* duplicate to have gotten this far, skip it. */
if (seq_seen != 0) /* already seen seq numbers */
goto nextIE;
if (segsize != 2)
goto nextIE;
sc->remote_seq = data[2];
if (sc->local_seq == data[3]) {
sc->local_seq++;
sc->seq_retries = 0;
/* Note that all 3 Frame protocols seem to
* not like 0 as a sequence number. */
if (sc->local_seq == 0)
sc->local_seq = 1;
}
break;
case 0x07:
case 0x57:
/* The remote tells us about a DLCI that it knows
* about. There may be many of these in a single
* status response */
switch (segsize) {
case 6:/* only on 'group of 4' */
dlci = ((u_short) data[2] & 0xff) << 8;
dlci |= (data[3] & 0xff);
if ((dlci < 1024) && (dlci > 0)) {
/* XXX */
}
break;
case 3:
dlci = ((u_short) data[2] & 0x3f) << 4;
dlci |= ((data[3] & 0x78) >> 3);
if ((dlci < 1024) && (dlci > 0)) {
/* set up the bottom half of the
* support for that dlci if it's not
* already been done */
/* store this information somewhere */
}
break;
default:
goto nextIE;
}
if (sc->dlci_state[dlci] != DLCI_UP) {
/* bring new DLCI to life */
/* may do more here some day */
if (sc->dlci_state[dlci] != DLCI_DOWN)
log(LOG_INFO,
"nglmi: DLCI %d became active\n",
dlci);
sc->dlci_state[dlci] = DLCI_UP;
}
break;
}
nextIE:
STEPBY(segsize + 2);
}
NG_FREE_M(m);
return (0);
drop:
NG_FREE_M(m);
return (EINVAL);
}
/*
* Check that a packet is entirely kosha.
* return 1 of ok, and 0 if not.
* All data is discarded if a 0 is returned.
*/
static int
nglmi_checkdata(hook_p hook, struct mbuf *m)
{
sc_p sc = hook->node->private;
u_char *data;
u_short packetlen;
unsigned short dlci;
u_char type;
u_char nextbyte;
int seq_seen = 0;
int resptype_seen = 0; /* 0 , 1 (partial) or 2 (full) */
int highest_dlci = 0;
packetlen = m->m_hdr.mh_len;
data = mtod(m, u_char *);
if (*data != 0x03) {
log(LOG_WARNING, "nglmi: unexpected value in LMI(%d)\n", 1);
goto reject;
}
STEPBY(1);
/* look at the protocol ID */
nextbyte = *data;
if (sc->flags & SCF_AUTO) {
SETLMITYPE(sc, SCF_NOLMI); /* start with a clean slate */
switch (nextbyte) {
case 0x8:
sc->protoID = 8;
break;
case 0x9:
SETLMITYPE(sc, SCF_GROUP4);
sc->protoID = 9;
break;
default:
log(LOG_WARNING, "nglmi: bad Protocol ID(%d)\n",
(int) nextbyte);
goto reject;
}
} else {
if (nextbyte != sc->protoID) {
log(LOG_WARNING, "nglmi: unexpected Protocol ID(%d)\n",
(int) nextbyte);
goto reject;
}
}
STEPBY(1);
/* check call reference (always null in non ISDN frame relay) */
if (*data != 0x00) {
log(LOG_WARNING, "nglmi: unexpected Call Reference (0x%x)\n",
data[-1]);
goto reject;
}
STEPBY(1);
/* check message type */
switch ((type = *data)) {
case 0x75: /* Status enquiry */
log(LOG_WARNING, "nglmi: unexpected message type(0x%x)\n",
data[-1]);
goto reject;
case 0x7D: /* Status message */
break;
default:
log(LOG_WARNING,
"nglmi: unexpected msg type(0x%x) \n", (int) type);
goto reject;
}
STEPBY(1);
/* Now check if there is a 'locking shift'. This is only seen in
* Annex D frames. Don't increment immediately as it might not be
* there. */
nextbyte = *data;
if (sc->flags & SCF_AUTO) {
if (!(GROUP4(sc))) {
if (nextbyte == 0x95) {
SETLMITYPE(sc, SCF_ANNEX_D);
STEPBY(1);
} else
SETLMITYPE(sc, SCF_ANNEX_A);
} else if (nextbyte == 0x95) {
log(LOG_WARNING, "nglmi: locking shift seen in G4\n");
goto reject;
}
} else {
if (ANNEXD(sc)) {
if (*data == 0x95)
STEPBY(1);
else {
log(LOG_WARNING,
"nglmi: locking shift missing\n");
goto reject;
}
} else if (*data == 0x95) {
log(LOG_WARNING, "nglmi: locking shift seen\n");
goto reject;
}
}
/* While there is more data in the status packet, keep processing
* status items. First make sure there is enough data for the
* segment descriptor's length field. */
while (packetlen >= 2) {
u_int segtype = data[0];
u_int segsize = data[1];
/* Now that we know how long it claims to be, make sure
* there is enough data for the next seg. */
if (packetlen < (segsize + 2)) {
log(LOG_WARNING, "nglmi: IE longer than packet\n");
break;
}
switch (segtype) {
case 0x01:
case 0x51:
/* According to MCI's HP analyser, we should just
* ignore if there is mor ethan one of these (?). */
if (resptype_seen) {
log(LOG_WARNING, "nglmi: dup MSGTYPE\n");
goto nextIE;
}
if (segsize != 1) {
log(LOG_WARNING, "nglmi: MSGTYPE wrong size\n");
goto reject;
}
/* The remote end tells us what kind of response
* this is. Only expect a type 0 or 1. if it was a
* full (type 0) check we just asked for a type
* full. */
switch (data[2]) {
case 1:/* partial */
if (sc->livs > sc->liv_per_full) {
log(LOG_WARNING,
"nglmi: LIV when FULL expected\n");
goto reject; /* need full */
}
resptype_seen = 1;
break;
case 0:/* full */
/* Full response is always acceptable */
resptype_seen = 2;
break;
default:
log(LOG_WARNING,
"nglmi: Unknown report type %d\n", data[2]);
goto reject;
}
break;
case 0x03:
case 0x53:
/* The remote tells us what it thinks the sequence
* numbers are. I would have thought that there
* needs to be one and only one of these, but MCI
* want us to just ignore extras. (?) */
if (resptype_seen == 0) {
log(LOG_WARNING, "nglmi: no TYPE before SEQ\n");
goto reject;
}
if (seq_seen != 0) /* already seen seq numbers */
goto nextIE;
if (segsize != 2) {
log(LOG_WARNING, "nglmi: bad SEQ sts size\n");
goto reject;
}
if (sc->local_seq != data[3]) {
log(LOG_WARNING, "nglmi: unexpected SEQ\n");
goto reject;
}
seq_seen = 1;
break;
case 0x07:
case 0x57:
/* The remote tells us about a DLCI that it knows
* about. There may be many of these in a single
* status response */
if (seq_seen != 1) { /* already seen seq numbers? */
log(LOG_WARNING,
"nglmi: No sequence before DLCI\n");
goto reject;
}
if (resptype_seen != 2) { /* must be full */
log(LOG_WARNING,
"nglmi: No resp type before DLCI\n");
goto reject;
}
if (GROUP4(sc)) {
if (segsize != 6) {
log(LOG_WARNING,
"nglmi: wrong IE segsize\n");
goto reject;
}
dlci = ((u_short) data[2] & 0xff) << 8;
dlci |= (data[3] & 0xff);
} else {
if (segsize != 3) {
log(LOG_WARNING,
"nglmi: DLCI headersize of %d"
" not supported\n", segsize - 1);
goto reject;
}
dlci = ((u_short) data[2] & 0x3f) << 4;
dlci |= ((data[3] & 0x78) >> 3);
}
/* async can only have one of these */
#if 0 /* async not yet accepted */
if (async && highest_dlci) {
log(LOG_WARNING,
"nglmi: Async with > 1 DLCI\n");
goto reject;
}
#endif
/* Annex D says these will always be Ascending, but
* the HP test for G4 says we should accept
* duplicates, so for now allow that. ( <= vs. < ) */
#if 0
/* MCI tests want us to accept out of order for AnxD */
if ((!GROUP4(sc)) && (dlci < highest_dlci)) {
/* duplicate or mis-ordered dlci */
/* (spec says they will increase in number) */
log(LOG_WARNING, "nglmi: DLCI out of order\n");
goto reject;
}
#endif
if (dlci > 1023) {
log(LOG_WARNING, "nglmi: DLCI out of range\n");
goto reject;
}
highest_dlci = dlci;
break;
default:
log(LOG_WARNING,
"nglmi: unknown LMI segment type %d\n", segtype);
}
nextIE:
STEPBY(segsize + 2);
}
if (packetlen != 0) { /* partial junk at end? */
log(LOG_WARNING,
"nglmi: %d bytes extra at end of packet\n", packetlen);
goto print;
}
if (resptype_seen == 0) {
log(LOG_WARNING, "nglmi: No response type seen\n");
goto reject; /* had no response type */
}
if (seq_seen == 0) {
log(LOG_WARNING, "nglmi: No sequence numbers seen\n");
goto reject; /* had no sequence numbers */
}
return (1);
print:
{
int i, j, k, pos;
char buf[100];
int loc;
u_char *bp = mtod(m, u_char *);
k = i = 0;
loc = (m->m_hdr.mh_len - packetlen);
log(LOG_WARNING, "nglmi: error at location %d\n", loc);
while (k < m->m_hdr.mh_len) {
pos = 0;
j = 0;
while ((j++ < 16) && k < m->m_hdr.mh_len) {
pos += sprintf(buf + pos, "%c%02x",
((loc == k) ? '>' : ' '),
bp[k]);
k++;
}
if (i == 0)
log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
else
log(LOG_WARNING, "%04d :%s\n", k, buf);
i++;
}
}
return (1);
reject:
{
int i, j, k, pos;
char buf[100];
int loc;
u_char *bp = mtod(m, u_char *);
k = i = 0;
loc = (m->m_hdr.mh_len - packetlen);
log(LOG_WARNING, "nglmi: error at location %d\n", loc);
while (k < m->m_hdr.mh_len) {
pos = 0;
j = 0;
while ((j++ < 16) && k < m->m_hdr.mh_len) {
pos += sprintf(buf + pos, "%c%02x",
((loc == k) ? '>' : ' '),
bp[k]);
k++;
}
if (i == 0)
log(LOG_WARNING, "nglmi: packet data:%s\n", buf);
else
log(LOG_WARNING, "%04d :%s\n", k, buf);
i++;
}
}
NG_FREE_M(m);
return (0);
}
/*
* Do local shutdown processing..
* Cut any remaining links and free our local resources.
*/
static int
nglmi_shutdown(node_p node)
{
const sc_p sc = node->private;
node->flags |= NG_INVALID;
node->private = NULL;
ng_unref(sc->node);
FREE(sc, M_NETGRAPH);
return (0);
}
/*
* Hook disconnection
* For this type, removal of any link except "debug" destroys the node.
*/
static int
nglmi_disconnect(hook_p hook)
{
const sc_p sc = hook->node->private;
/* OK to remove debug hook(s) */
if (hook->private == NULL)
return (0);
/* Stop timer if it's currently active */
if (sc->flags & SCF_CONNECTED)
untimeout(LMI_ticker, sc, sc->handle);
/* Self-destruct */
if ((hook->node->flags & NG_INVALID) == 0)
ng_rmnode_self(hook->node);
return (0);
}