FreeBSD-5.3/sys/netgraph/ng_rfc1490.c
/*
* ng_rfc1490.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: src/sys/netgraph/ng_rfc1490.c,v 1.23 2004/06/25 21:11:14 julian Exp $
* $Whistle: ng_rfc1490.c,v 1.22 1999/11/01 09:24:52 julian Exp $
*/
/*
* This node does RFC 1490 multiplexing.
*
* NOTE: RFC 1490 is updated by RFC 2427.
*/
#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/errno.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_rfc1490.h>
/*
* DEFINITIONS
*/
/* Q.922 stuff -- see RFC 1490 */
#define HDLC_UI 0x03
#define NLPID_IP 0xCC
#define NLPID_PPP 0xCF
#define NLPID_SNAP 0x80
#define NLPID_Q933 0x08
#define NLPID_CLNP 0x81
#define NLPID_ESIS 0x82
#define NLPID_ISIS 0x83
#define ERROUT(x) do { error = (x); goto done; } while (0)
/* Encapsulation methods we understand */
enum {
NG_RFC1490_ENCAP_IETF_IP = 1, /* see RFC2427, chapter 7, table 1 */
NG_RFC1490_ENCAP_IETF_SNAP, /* see RFC2427, chapter 7, table 2 */
NG_RFC1490_ENCAP_CISCO, /* Cisco's proprietary encapsulation */
};
struct ng_rfc1490_encap_t {
u_int8_t method;
const char *name;
};
static const struct ng_rfc1490_encap_t ng_rfc1490_encaps[] = {
{ NG_RFC1490_ENCAP_IETF_IP, "ietf-ip" },
{ NG_RFC1490_ENCAP_IETF_SNAP, "ietf-snap" },
{ NG_RFC1490_ENCAP_CISCO, "cisco" },
{ 0, NULL},
};
/* Node private data */
struct ng_rfc1490_private {
hook_p downlink;
hook_p ppp;
hook_p inet;
hook_p ethernet;
const struct ng_rfc1490_encap_t *enc;
};
typedef struct ng_rfc1490_private *priv_p;
/* Netgraph node methods */
static ng_constructor_t ng_rfc1490_constructor;
static ng_rcvmsg_t ng_rfc1490_rcvmsg;
static ng_shutdown_t ng_rfc1490_shutdown;
static ng_newhook_t ng_rfc1490_newhook;
static ng_rcvdata_t ng_rfc1490_rcvdata;
static ng_disconnect_t ng_rfc1490_disconnect;
/* List of commands and how to convert arguments to/from ASCII */
static const struct ng_cmdlist ng_rfc1490_cmds[] = {
{
NGM_RFC1490_COOKIE,
NGM_RFC1490_SET_ENCAP,
"setencap",
&ng_parse_string_type,
NULL
},
{
NGM_RFC1490_COOKIE,
NGM_RFC1490_GET_ENCAP,
"getencap",
NULL,
&ng_parse_string_type
},
{ 0 }
};
/* Node type descriptor */
static struct ng_type typestruct = {
.version = NG_ABI_VERSION,
.name = NG_RFC1490_NODE_TYPE,
.constructor = ng_rfc1490_constructor,
.rcvmsg = ng_rfc1490_rcvmsg,
.shutdown = ng_rfc1490_shutdown,
.newhook = ng_rfc1490_newhook,
.rcvdata = ng_rfc1490_rcvdata,
.disconnect = ng_rfc1490_disconnect,
.cmdlist = ng_rfc1490_cmds,
};
NETGRAPH_INIT(rfc1490, &typestruct);
/************************************************************************
NETGRAPH NODE STUFF
************************************************************************/
/*
* Node constructor
*/
static int
ng_rfc1490_constructor(node_p node)
{
priv_p priv;
/* Allocate private structure */
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (priv == NULL)
return (ENOMEM);
/* Initialize to default encapsulation method - ietf-ip */
priv->enc = ng_rfc1490_encaps;
NG_NODE_SET_PRIVATE(node, priv);
/* Done */
return (0);
}
/*
* Give our ok for a hook to be added
*/
static int
ng_rfc1490_newhook(node_p node, hook_p hook, const char *name)
{
const priv_p priv = NG_NODE_PRIVATE(node);
if (!strcmp(name, NG_RFC1490_HOOK_DOWNSTREAM)) {
if (priv->downlink)
return (EISCONN);
priv->downlink = hook;
} else if (!strcmp(name, NG_RFC1490_HOOK_PPP)) {
if (priv->ppp)
return (EISCONN);
priv->ppp = hook;
} else if (!strcmp(name, NG_RFC1490_HOOK_INET)) {
if (priv->inet)
return (EISCONN);
priv->inet = hook;
} else if (!strcmp(name, NG_RFC1490_HOOK_ETHERNET)) {
if (priv->ethernet)
return (EISCONN);
priv->ethernet = hook;
} else
return (EINVAL);
return (0);
}
/*
* Receive a control message.
*/
static int
ng_rfc1490_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const priv_p priv = NG_NODE_PRIVATE(node);
struct ng_mesg *msg;
struct ng_mesg *resp = NULL;
int error = 0;
NGI_GET_MSG(item, msg);
if (msg->header.typecookie == NGM_RFC1490_COOKIE) {
switch (msg->header.cmd) {
case NGM_RFC1490_SET_ENCAP:
{
const struct ng_rfc1490_encap_t *enc;
char *s;
size_t len;
if (msg->header.arglen == 0)
ERROUT(EINVAL);
s = (char *)msg->data;
len = msg->header.arglen - 1;
/* Search for matching encapsulation method */
for (enc = ng_rfc1490_encaps; enc->method != 0; enc++ )
if ((strlen(enc->name) == len) &&
!strncmp(enc->name, s, len))
break; /* found */
if (enc->method != 0)
priv->enc = enc;
else
error = EINVAL;
break;
}
case NGM_RFC1490_GET_ENCAP:
NG_MKRESPONSE(resp, msg, strlen(priv->enc->name) + 1, M_NOWAIT);
if (resp == NULL)
ERROUT(ENOMEM);
strlcpy((char *)resp->data, priv->enc->name,
strlen(priv->enc->name) + 1);
break;
default:
error = EINVAL;
break;
}
} else
error = EINVAL;
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Receive data on a hook and encapsulate according to RFC 1490.
* Only those nodes marked (*) are supported by this routine so far.
*
* Q.922 control
* |
* |
* ---------------------------------------------------------------------
* | 0x03 | |
* UI I Frame Cisco
* | | Encapsulation
* --------------------------------- -------------- |
* | 0x08 | 0x81 |0xCC |0xCF | 0x00 |..01.... |..10.... --------------
* | | | | | 0x80 | | |0x800 |
* Q.933 CLNP IP(*) PPP(*) SNAP ISO 8208 ISO 8208 | |
* | (rfc1973) | Modulo 8 Modulo 128 IP(*) Others
* | |
* -------------------- OUI
* | | |
* L2 ID L3 ID -------------------------
* | User |00-80-C2 |00-00-00
* | specified | |
* | 0x70 PID Ethertype
* | | |
* ------------------- -----------------... ----------
* |0x51 |0x4E | |0x4C |0x7 |0xB | |0x806 |
* | | | | | | | | |
* 7776 Q.922 Others 802.2 802.3(*) 802.6 Others IP(*) Others
*
*
*/
#define MAX_ENCAPS_HDR 8
#define OUICMP(P,A,B,C) ((P)[0]==(A) && (P)[1]==(B) && (P)[2]==(C))
static int
ng_rfc1490_rcvdata(hook_p hook, item_p item)
{
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
int error = 0;
struct mbuf *m;
NGI_GET_M(item, m);
if (hook == priv->downlink) {
const u_char *start;
const u_char *ptr;
if (m->m_len < MAX_ENCAPS_HDR
&& !(m = m_pullup(m, MAX_ENCAPS_HDR)))
ERROUT(ENOBUFS);
ptr = start = mtod(m, const u_char *);
if (priv->enc->method == NG_RFC1490_ENCAP_CISCO)
goto switch_on_etype;
/* Must be UI frame */
if (*ptr++ != HDLC_UI)
ERROUT(0);
/* Eat optional zero pad byte */
if (*ptr == 0x00)
ptr++;
/* Multiplex on NLPID */
switch (*ptr++) {
case NLPID_SNAP:
if (OUICMP(ptr, 0, 0, 0)) { /* It's an ethertype */
u_int16_t etype;
ptr += 3;
switch_on_etype: etype = ntohs(*((const u_int16_t *)ptr));
ptr += 2;
m_adj(m, ptr - start);
switch (etype) {
case ETHERTYPE_IP:
NG_FWD_NEW_DATA(error, item,
priv->inet, m);
break;
case ETHERTYPE_ARP:
case ETHERTYPE_REVARP:
default:
ERROUT(0);
}
} else if (OUICMP(ptr, 0x00, 0x80, 0xc2)) {
/* 802.1 bridging */
ptr += 3;
if (*ptr++ != 0x00)
ERROUT(0); /* unknown PID octet 0 */
if (*ptr++ != 0x07)
ERROUT(0); /* not FCS-less 802.3 */
m_adj(m, ptr - start);
NG_FWD_NEW_DATA(error, item, priv->ethernet, m);
} else /* Other weird stuff... */
ERROUT(0);
break;
case NLPID_IP:
m_adj(m, ptr - start);
NG_FWD_NEW_DATA(error, item, priv->inet, m);
break;
case NLPID_PPP:
m_adj(m, ptr - start);
NG_FWD_NEW_DATA(error, item, priv->ppp, m);
break;
case NLPID_Q933:
case NLPID_CLNP:
case NLPID_ESIS:
case NLPID_ISIS:
ERROUT(0);
default: /* Try PPP (see RFC 1973) */
ptr--; /* NLPID becomes PPP proto */
if ((*ptr & 0x01) == 0x01)
ERROUT(0);
m_adj(m, ptr - start);
NG_FWD_NEW_DATA(error, item, priv->ppp, m);
break;
}
} else if (hook == priv->ppp) {
M_PREPEND(m, 2, M_DONTWAIT); /* Prepend PPP NLPID */
if (!m)
ERROUT(ENOBUFS);
mtod(m, u_char *)[0] = HDLC_UI;
mtod(m, u_char *)[1] = NLPID_PPP;
NG_FWD_NEW_DATA(error, item, priv->downlink, m);
} else if (hook == priv->inet) {
switch (priv->enc->method) {
case NG_RFC1490_ENCAP_IETF_IP:
M_PREPEND(m, 2, M_DONTWAIT); /* Prepend IP NLPID */
if (!m)
ERROUT(ENOBUFS);
mtod(m, u_char *)[0] = HDLC_UI;
mtod(m, u_char *)[1] = NLPID_IP;
break;
case NG_RFC1490_ENCAP_IETF_SNAP:
/*
* According to RFC2427 frame should begin with
* HDLC_UI PAD NLIPID OUI PID
* 03 00 80 00 00 00 08 00
*/
M_PREPEND(m, 8, M_DONTWAIT);
if (!m)
ERROUT(ENOBUFS);
mtod(m, u_char *)[0] = HDLC_UI;
mtod(m, u_char *)[1] = 0x00; /* PAD */
mtod(m, u_char *)[2] = NLPID_SNAP;
bzero((char *)(mtod(m, u_char *) + 3), 3); /* OUI 0-0-0 */
*((u_int16_t *)mtod(m, u_int16_t *) + 6/sizeof(u_int16_t))
= htons(ETHERTYPE_IP); /* PID */
break;
case NG_RFC1490_ENCAP_CISCO:
M_PREPEND(m, 2, M_DONTWAIT); /* Prepend IP ethertype */
if (!m)
ERROUT(ENOBUFS);
*((u_int16_t *)mtod(m, u_int16_t *)) = htons(ETHERTYPE_IP);
break;
}
NG_FWD_NEW_DATA(error, item, priv->downlink, m);
} else if (hook == priv->ethernet) {
M_PREPEND(m, 8, M_DONTWAIT); /* Prepend NLPID, OUI, PID */
if (!m)
ERROUT(ENOBUFS);
mtod(m, u_char *)[0] = HDLC_UI;
mtod(m, u_char *)[1] = 0x00; /* pad */
mtod(m, u_char *)[2] = NLPID_SNAP;
mtod(m, u_char *)[3] = 0x00; /* OUI */
mtod(m, u_char *)[4] = 0x80;
mtod(m, u_char *)[5] = 0xc2;
mtod(m, u_char *)[6] = 0x00; /* PID */
mtod(m, u_char *)[7] = 0x07;
NG_FWD_NEW_DATA(error, item, priv->downlink, m);
} else
panic(__func__);
done:
if (item)
NG_FREE_ITEM(item);
NG_FREE_M(m);
return (error);
}
/*
* Nuke node
*/
static int
ng_rfc1490_shutdown(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
/* Take down netgraph node */
bzero(priv, sizeof(*priv));
FREE(priv, M_NETGRAPH);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(node); /* let the node escape */
return (0);
}
/*
* Hook disconnection
*/
static int
ng_rfc1490_disconnect(hook_p hook)
{
const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
ng_rmnode_self(NG_HOOK_NODE(hook));
else if (hook == priv->downlink)
priv->downlink = NULL;
else if (hook == priv->inet)
priv->inet = NULL;
else if (hook == priv->ppp)
priv->ppp = NULL;
else if (hook == priv->ethernet)
priv->ethernet = NULL;
else
panic(__func__);
return (0);
}