mirror of
https://github.com/freebsd/freebsd-src
synced 2024-09-06 17:18:32 +00:00
502 lines
13 KiB
C
502 lines
13 KiB
C
/*
|
|
* ng_frame_relay.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>
|
|
* $Whistle: ng_frame_relay.c,v 1.20 1999/11/01 09:24:51 julian Exp $
|
|
*/
|
|
|
|
/*
|
|
* This node implements the frame relay protocol, not including
|
|
* the LMI line management. This means basically keeping track
|
|
* of which DLCI's are active, doing frame (de)multiplexing, etc.
|
|
*
|
|
* It has a 'downstream' hook that goes to the line, and a
|
|
* hook for each DLCI (eg, 'dlci16').
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/errno.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/syslog.h>
|
|
#include <sys/ctype.h>
|
|
|
|
#include <netgraph/ng_message.h>
|
|
#include <netgraph/netgraph.h>
|
|
#include <netgraph/ng_frame_relay.h>
|
|
|
|
/*
|
|
* Line info, and status per channel.
|
|
*/
|
|
struct ctxinfo { /* one per active hook */
|
|
u_int flags;
|
|
#define CHAN_VALID 0x01 /* assigned to a channel */
|
|
#define CHAN_ACTIVE 0x02 /* bottom level active */
|
|
int dlci; /* the dlci assigned to this context */
|
|
hook_p hook; /* if there's a hook assigned.. */
|
|
};
|
|
|
|
#define MAX_CT 16 /* # of dlci's active at a time (POWER OF 2!) */
|
|
struct frmrel_softc {
|
|
int unit; /* which card are we? */
|
|
int datahooks; /* number of data hooks attached */
|
|
node_p node; /* netgraph node */
|
|
int addrlen; /* address header length */
|
|
int flags; /* state */
|
|
int mtu; /* guess */
|
|
u_char remote_seq; /* sequence number the remote sent */
|
|
u_char local_seq; /* sequence number the remote rcvd */
|
|
u_short ALT[1024]; /* map DLCIs to CTX */
|
|
#define CTX_VALID 0x8000 /* this bit means it's a valid CTX */
|
|
#define CTX_VALUE (MAX_CT - 1) /* mask for context part */
|
|
struct ctxinfo channel[MAX_CT];
|
|
struct ctxinfo downstream;
|
|
};
|
|
typedef struct frmrel_softc *sc_p;
|
|
|
|
#define BYTEX_EA 0x01 /* End Address. Always 0 on byte1 */
|
|
#define BYTE1_C_R 0x02
|
|
#define BYTE2_FECN 0x08 /* forwards congestion notification */
|
|
#define BYTE2_BECN 0x04 /* Backward congestion notification */
|
|
#define BYTE2_DE 0x02 /* Discard elligability */
|
|
#define LASTBYTE_D_C 0x02 /* last byte is dl_core or dlci info */
|
|
|
|
/* Used to do headers */
|
|
const static struct segment {
|
|
u_char mask;
|
|
u_char shift;
|
|
u_char width;
|
|
} makeup[] = {
|
|
{ 0xfc, 2, 6 },
|
|
{ 0xf0, 4, 4 },
|
|
{ 0xfe, 1, 7 },
|
|
{ 0xfc, 2, 6 }
|
|
};
|
|
|
|
#define SHIFTIN(segment, byte, dlci) \
|
|
{ \
|
|
(dlci) <<= (segment)->width; \
|
|
(dlci) |= \
|
|
(((byte) & (segment)->mask) >> (segment)->shift); \
|
|
}
|
|
|
|
#define SHIFTOUT(segment, byte, dlci) \
|
|
{ \
|
|
(byte) |= (((dlci) << (segment)->shift) & (segment)->mask); \
|
|
(dlci) >>= (segment)->width; \
|
|
}
|
|
|
|
/* Netgraph methods */
|
|
static ng_constructor_t ngfrm_constructor;
|
|
static ng_shutdown_t ngfrm_shutdown;
|
|
static ng_newhook_t ngfrm_newhook;
|
|
static ng_rcvdata_t ngfrm_rcvdata;
|
|
static ng_disconnect_t ngfrm_disconnect;
|
|
|
|
/* Other internal functions */
|
|
static int ngfrm_decode(node_p node, item_p item);
|
|
static int ngfrm_addrlen(char *hdr);
|
|
static int ngfrm_allocate_CTX(sc_p sc, int dlci);
|
|
|
|
/* Netgraph type */
|
|
static struct ng_type typestruct = {
|
|
.version = NG_ABI_VERSION,
|
|
.name = NG_FRAMERELAY_NODE_TYPE,
|
|
.constructor = ngfrm_constructor,
|
|
.shutdown = ngfrm_shutdown,
|
|
.newhook = ngfrm_newhook,
|
|
.rcvdata = ngfrm_rcvdata,
|
|
.disconnect = ngfrm_disconnect,
|
|
};
|
|
NETGRAPH_INIT(framerelay, &typestruct);
|
|
|
|
#define ERROUT(x) do { error = (x); goto done; } while (0)
|
|
|
|
/*
|
|
* Given a DLCI, return the index of the context table entry for it,
|
|
* Allocating a new one if needs be, or -1 if none available.
|
|
*/
|
|
static int
|
|
ngfrm_allocate_CTX(sc_p sc, int dlci)
|
|
{
|
|
u_int ctxnum = -1; /* what ctx number we are using */
|
|
volatile struct ctxinfo *CTXp = NULL;
|
|
|
|
/* Sanity check the dlci value */
|
|
if (dlci > 1023)
|
|
return (-1);
|
|
|
|
/* Check to see if we already have an entry for this DLCI */
|
|
if (sc->ALT[dlci]) {
|
|
if ((ctxnum = sc->ALT[dlci] & CTX_VALUE) < MAX_CT) {
|
|
CTXp = sc->channel + ctxnum;
|
|
} else {
|
|
ctxnum = -1;
|
|
sc->ALT[dlci] = 0; /* paranoid but... */
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If the index has no valid entry yet, then we need to allocate a
|
|
* CTX number to it
|
|
*/
|
|
if (CTXp == NULL) {
|
|
for (ctxnum = 0; ctxnum < MAX_CT; ctxnum++) {
|
|
/*
|
|
* If the VALID flag is empty it is unused
|
|
*/
|
|
if ((sc->channel[ctxnum].flags & CHAN_VALID) == 0) {
|
|
bzero(sc->channel + ctxnum,
|
|
sizeof(struct ctxinfo));
|
|
CTXp = sc->channel + ctxnum;
|
|
sc->ALT[dlci] = ctxnum | CTX_VALID;
|
|
sc->channel[ctxnum].dlci = dlci;
|
|
sc->channel[ctxnum].flags = CHAN_VALID;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we still don't have a CTX pointer, then we never found a free
|
|
* spot so give up now..
|
|
*/
|
|
if (!CTXp) {
|
|
log(LOG_ERR, "No CTX available for dlci %d\n", dlci);
|
|
return (-1);
|
|
}
|
|
return (ctxnum);
|
|
}
|
|
|
|
/*
|
|
* Node constructor
|
|
*/
|
|
static int
|
|
ngfrm_constructor(node_p node)
|
|
{
|
|
sc_p sc;
|
|
|
|
sc = malloc(sizeof(*sc), M_NETGRAPH, M_WAITOK | M_ZERO);
|
|
sc->addrlen = 2; /* default */
|
|
|
|
/* Link the node and our private info */
|
|
NG_NODE_SET_PRIVATE(node, sc);
|
|
sc->node = node;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Add a new hook
|
|
*
|
|
* We allow hooks called "debug", "downstream" and dlci[0-1023]
|
|
* The hook's private info points to our stash of info about that
|
|
* channel. A NULL pointer is debug and a DLCI of -1 means downstream.
|
|
*/
|
|
static int
|
|
ngfrm_newhook(node_p node, hook_p hook, const char *name)
|
|
{
|
|
const sc_p sc = NG_NODE_PRIVATE(node);
|
|
const char *cp;
|
|
char *eptr;
|
|
int dlci = 0;
|
|
int ctxnum;
|
|
|
|
/* Check if it's our friend the control hook */
|
|
if (strcmp(name, NG_FRAMERELAY_HOOK_DEBUG) == 0) {
|
|
NG_HOOK_SET_PRIVATE(hook, NULL); /* paranoid */
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* All other hooks either start with 'dlci' and have a decimal
|
|
* trailing channel number up to 4 digits, or are the downstream
|
|
* hook.
|
|
*/
|
|
if (strncmp(name, NG_FRAMERELAY_HOOK_DLCI,
|
|
strlen(NG_FRAMERELAY_HOOK_DLCI)) != 0) {
|
|
/* It must be the downstream connection */
|
|
if (strcmp(name, NG_FRAMERELAY_HOOK_DOWNSTREAM) != 0)
|
|
return EINVAL;
|
|
|
|
/* Make sure we haven't already got one (paranoid) */
|
|
if (sc->downstream.hook)
|
|
return (EADDRINUSE);
|
|
|
|
/* OK add it */
|
|
NG_HOOK_SET_PRIVATE(hook, &sc->downstream);
|
|
sc->downstream.hook = hook;
|
|
sc->downstream.dlci = -1;
|
|
sc->downstream.flags |= CHAN_ACTIVE;
|
|
sc->datahooks++;
|
|
return (0);
|
|
}
|
|
|
|
/* Must be a dlci hook at this point */
|
|
cp = name + strlen(NG_FRAMERELAY_HOOK_DLCI);
|
|
if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
|
|
return (EINVAL);
|
|
dlci = (int)strtoul(cp, &eptr, 10);
|
|
if (*eptr != '\0' || dlci < 0 || dlci > 1023)
|
|
return (EINVAL);
|
|
|
|
/*
|
|
* We have a dlci, now either find it, or allocate it. It's possible
|
|
* that we might have seen packets for it already and made an entry
|
|
* for it.
|
|
*/
|
|
ctxnum = ngfrm_allocate_CTX(sc, dlci);
|
|
if (ctxnum == -1)
|
|
return (ENOBUFS);
|
|
|
|
/*
|
|
* Be paranoid: if it's got a hook already, that dlci is in use .
|
|
* Generic code can not catch all the synonyms (e.g. dlci016 vs
|
|
* dlci16)
|
|
*/
|
|
if (sc->channel[ctxnum].hook != NULL)
|
|
return (EADDRINUSE);
|
|
|
|
/*
|
|
* Put our hooks into it (pun not intended)
|
|
*/
|
|
sc->channel[ctxnum].flags |= CHAN_ACTIVE;
|
|
NG_HOOK_SET_PRIVATE(hook, sc->channel + ctxnum);
|
|
sc->channel[ctxnum].hook = hook;
|
|
sc->datahooks++;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Count up the size of the address header if we don't already know
|
|
*/
|
|
int
|
|
ngfrm_addrlen(char *hdr)
|
|
{
|
|
if (hdr[0] & BYTEX_EA)
|
|
return 0;
|
|
if (hdr[1] & BYTEX_EA)
|
|
return 2;
|
|
if (hdr[2] & BYTEX_EA)
|
|
return 3;
|
|
if (hdr[3] & BYTEX_EA)
|
|
return 4;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Receive data packet
|
|
*/
|
|
static int
|
|
ngfrm_rcvdata(hook_p hook, item_p item)
|
|
{
|
|
struct ctxinfo *const ctxp = NG_HOOK_PRIVATE(hook);
|
|
struct mbuf *m = NULL;
|
|
int error = 0;
|
|
int dlci;
|
|
sc_p sc;
|
|
int alen;
|
|
char *data;
|
|
|
|
/* Data doesn't come in from just anywhere (e.g debug hook) */
|
|
if (ctxp == NULL)
|
|
ERROUT(ENETDOWN);
|
|
|
|
/* If coming from downstream, decode it to a channel */
|
|
dlci = ctxp->dlci;
|
|
if (dlci == -1)
|
|
return (ngfrm_decode(NG_HOOK_NODE(hook), item));
|
|
|
|
NGI_GET_M(item, m);
|
|
/* Derive the softc we will need */
|
|
sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
|
|
|
|
/* If there is no live channel, throw it away */
|
|
if ((sc->downstream.hook == NULL)
|
|
|| ((ctxp->flags & CHAN_ACTIVE) == 0))
|
|
ERROUT(ENETDOWN);
|
|
|
|
/* Store the DLCI on the front of the packet */
|
|
alen = sc->addrlen;
|
|
if (alen == 0)
|
|
alen = 2; /* default value for transmit */
|
|
M_PREPEND(m, alen, M_NOWAIT);
|
|
if (m == NULL)
|
|
ERROUT(ENOBUFS);
|
|
data = mtod(m, char *);
|
|
|
|
/*
|
|
* Shift the lowest bits into the address field until we are done.
|
|
* First byte is MSBits of addr so work backwards.
|
|
*/
|
|
switch (alen) {
|
|
case 2:
|
|
data[0] = data[1] = '\0';
|
|
SHIFTOUT(makeup + 1, data[1], dlci);
|
|
SHIFTOUT(makeup + 0, data[0], dlci);
|
|
data[1] |= BYTEX_EA;
|
|
break;
|
|
case 3:
|
|
data[0] = data[1] = data[2] = '\0';
|
|
SHIFTOUT(makeup + 3, data[2], dlci); /* 3 and 2 is correct */
|
|
SHIFTOUT(makeup + 1, data[1], dlci);
|
|
SHIFTOUT(makeup + 0, data[0], dlci);
|
|
data[2] |= BYTEX_EA;
|
|
break;
|
|
case 4:
|
|
data[0] = data[1] = data[2] = data[3] = '\0';
|
|
SHIFTOUT(makeup + 3, data[3], dlci);
|
|
SHIFTOUT(makeup + 2, data[2], dlci);
|
|
SHIFTOUT(makeup + 1, data[1], dlci);
|
|
SHIFTOUT(makeup + 0, data[0], dlci);
|
|
data[3] |= BYTEX_EA;
|
|
break;
|
|
default:
|
|
panic("%s", __func__);
|
|
}
|
|
|
|
/* Send it */
|
|
NG_FWD_NEW_DATA(error, item, sc->downstream.hook, m);
|
|
return (error);
|
|
|
|
done:
|
|
NG_FREE_ITEM(item);
|
|
NG_FREE_M(m);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Decode an incoming frame coming from the switch
|
|
*/
|
|
static int
|
|
ngfrm_decode(node_p node, item_p item)
|
|
{
|
|
const sc_p sc = NG_NODE_PRIVATE(node);
|
|
char *data;
|
|
int alen;
|
|
u_int dlci = 0;
|
|
int error = 0;
|
|
int ctxnum;
|
|
struct mbuf *m;
|
|
|
|
NGI_GET_M(item, m);
|
|
if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL)
|
|
ERROUT(ENOBUFS);
|
|
data = mtod(m, char *);
|
|
if ((alen = sc->addrlen) == 0) {
|
|
sc->addrlen = alen = ngfrm_addrlen(data);
|
|
}
|
|
switch (alen) {
|
|
case 2:
|
|
SHIFTIN(makeup + 0, data[0], dlci);
|
|
SHIFTIN(makeup + 1, data[1], dlci);
|
|
break;
|
|
case 3:
|
|
SHIFTIN(makeup + 0, data[0], dlci);
|
|
SHIFTIN(makeup + 1, data[1], dlci);
|
|
SHIFTIN(makeup + 3, data[2], dlci); /* 3 and 2 is correct */
|
|
break;
|
|
case 4:
|
|
SHIFTIN(makeup + 0, data[0], dlci);
|
|
SHIFTIN(makeup + 1, data[1], dlci);
|
|
SHIFTIN(makeup + 2, data[2], dlci);
|
|
SHIFTIN(makeup + 3, data[3], dlci);
|
|
break;
|
|
default:
|
|
ERROUT(EINVAL);
|
|
}
|
|
|
|
if (dlci > 1023)
|
|
ERROUT(EINVAL);
|
|
ctxnum = sc->ALT[dlci];
|
|
if ((ctxnum & CTX_VALID) && sc->channel[ctxnum &= CTX_VALUE].hook) {
|
|
/* Send it */
|
|
m_adj(m, alen);
|
|
NG_FWD_NEW_DATA(error, item, sc->channel[ctxnum].hook, m);
|
|
return (error);
|
|
} else {
|
|
error = ENETDOWN;
|
|
}
|
|
done:
|
|
NG_FREE_ITEM(item);
|
|
NG_FREE_M(m);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Shutdown node
|
|
*/
|
|
static int
|
|
ngfrm_shutdown(node_p node)
|
|
{
|
|
const sc_p sc = NG_NODE_PRIVATE(node);
|
|
|
|
NG_NODE_SET_PRIVATE(node, NULL);
|
|
free(sc, M_NETGRAPH);
|
|
NG_NODE_UNREF(node);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Hook disconnection
|
|
*
|
|
* Invalidate the private data associated with this dlci.
|
|
* For this type, removal of the last link resets tries to destroy the node.
|
|
*/
|
|
static int
|
|
ngfrm_disconnect(hook_p hook)
|
|
{
|
|
const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
|
|
struct ctxinfo *const cp = NG_HOOK_PRIVATE(hook);
|
|
int dlci;
|
|
|
|
/* If it's a regular dlci hook, then free resources etc.. */
|
|
if (cp != NULL) {
|
|
cp->hook = NULL;
|
|
dlci = cp->dlci;
|
|
if (dlci != -1)
|
|
sc->ALT[dlci] = 0;
|
|
cp->flags = 0;
|
|
sc->datahooks--;
|
|
}
|
|
if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
|
|
&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
|
|
ng_rmnode_self(NG_HOOK_NODE(hook));
|
|
return (0);
|
|
}
|