Whistle's Netgraph link-layer (sometimes more) networking infrastructure.

Been in production for 3 years now. Gives Instant Frame relay to if_sr
and if_ar drivers, and PPPOE support soon. See:
ftp://ftp.whistle.com/pub/archie/netgraph/index.html
for on-line manual pages.

Reviewed by: Doug Rabson (dfr@freebsd.org)
Obtained from:  Whistle CVS tree

1 files changed, 347 insertions, 0 deletions

diff --git a/sys/netgraph/ng_rfc1490.c b/sys/netgraph/ng_rfc1490.c
new file mode 100644
index 0000000..3649476
--- /dev/null
+++ b/sys/netgraph/ng_rfc1490.c
@@ -0,0 +1,347 @@
+
+/*
+ * 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@whistle.com>
+ *
+ * $FreeBSD$
+ * $Whistle: ng_rfc1490.c,v 1.19 1999/01/28 23:54:53 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/conf.h>
+#include <sys/errno.h>
+#include <sys/socket.h>
+#include <sys/syslog.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_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
+
+/* Node private data */
+struct private {
+	hook_p  downlink;
+	hook_p  ppp;
+	hook_p  inet;
+};
+typedef struct private *priv_p;
+
+/* Netgraph node methods */
+static int	ng_rfc1490_constructor(node_p * nodep);
+static int	ng_rfc1490_rcvmsg(node_p node, struct ng_mesg * msg,
+		    const char *retaddr, struct ng_mesg **resp);
+static int	ng_rfc1490_rmnode(node_p node);
+static int	ng_rfc1490_newhook(node_p node, hook_p hook, const char *name);
+static int	ng_rfc1490_rcvdata(hook_p hook, struct mbuf *m, meta_p meta);
+static int	ng_rfc1490_disconnect(hook_p hook);
+
+/* Node type descriptor */
+static struct ng_type typestruct = {
+	NG_VERSION,
+	NG_RFC1490_NODE_TYPE,
+	NULL,
+	ng_rfc1490_constructor,
+	ng_rfc1490_rcvmsg,
+	ng_rfc1490_rmnode,
+	ng_rfc1490_newhook,
+	NULL,
+	NULL,
+	ng_rfc1490_rcvdata,
+	ng_rfc1490_rcvdata,
+	ng_rfc1490_disconnect
+};
+NETGRAPH_INIT(rfc1490, &typestruct);
+
+/************************************************************************
+			NETGRAPH NODE STUFF
+ ************************************************************************/
+
+/*
+ * Node constructor
+ */
+static int
+ng_rfc1490_constructor(node_p *nodep)
+{
+	priv_p priv;
+	int error;
+
+	/* Allocate private structure */
+	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK);
+	if (priv == NULL)
+		return (ENOMEM);
+	bzero(priv, sizeof(*priv));
+
+	/* Call generic node constructor */
+	if ((error = ng_make_node_common(&typestruct, nodep))) {
+		FREE(priv, M_NETGRAPH);
+		return (error);
+	}
+	(*nodep)->private = 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 = node->private;
+
+	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
+		return (EINVAL);
+	return (0);
+}
+
+/*
+ * Receive a control message. We don't support any special ones.
+ */
+static int
+ng_rfc1490_rcvmsg(node_p node, struct ng_mesg *msg,
+		  const char *raddr, struct ng_mesg **rp)
+{
+	FREE(msg, M_NETGRAPH);
+	return (EINVAL);
+}
+
+/*
+ * 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
+ *            |                                          |
+ *      ---------------------------------         --------------
+ *      | 0x08  | 0x81  |0xCC   |0xCF   | 0x00    |..01....    |..10....
+ *      |       |       |       |       | 0x80    |            |
+ *     Q.933   CLNP    IP(*)   PPP(*)  SNAP     ISO 8208    ISO 8208
+ *      |                    (rfc1973)  |       Modulo 8    Modulo 128
+ *      |                               |
+ *      --------------------           OUI
+ *      |                  |            |
+ *     L2 ID              L3 ID      -------------------------
+ *      |               User         |00-80-C2               |00-00-00
+ *      |               specified    |                       |
+ *      |               0x70        PID                     Ethertype
+ *      |                            |                       |
+ *      -------------------        --------------...        ----------
+ *      |0x51 |0x4E |     |0x4C    |0x1   |0xB  |           |0x806   |
+ *      |     |     |     |        |      |     |           |        |
+ *     7776  Q.922 Others 802.2   802.3  802.6 Others       ARP(*)  Others
+ *
+ *
+ */
+
+#define MAX_ENCAPS_HDR	8
+#define ERROUT(x)	do { error = (x); goto done; } while (0)
+#define OUICMP(P,A,B,C)	((P)[0]==(A) && (P)[1]==(B) && (P)[2]==(C))
+
+static int
+ng_rfc1490_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
+{
+	const node_p node = hook->node;
+	const priv_p priv = node->private;
+	int error = 0;
+
+	if (hook == priv->downlink) {
+		u_char *start, *ptr;
+
+		if (!m || !(m = m_pullup(m, MAX_ENCAPS_HDR)))
+			ERROUT(ENOBUFS);
+		ptr = start = mtod(m, u_char *);
+
+		/* 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;
+				etype = ntohs(*((u_int16_t *) ptr));
+				ptr += 2;
+				m_adj(m, ptr - start);
+				switch (etype) {
+				case ETHERTYPE_IP:
+					NG_SEND_DATA(error,
+					    priv->inet, m, meta);
+					break;
+				case ETHERTYPE_ARP:
+				case ETHERTYPE_REVARP:
+				default:
+					ERROUT(0);
+				}
+			} else if (OUICMP(ptr, 0x00, 0x80, 0xc2))	/* 802.1 bridging */
+				ERROUT(0);
+			else	/* Other weird stuff... */
+				ERROUT(0);
+			break;
+		case NLPID_IP:
+			m_adj(m, ptr - start);
+			NG_SEND_DATA(error, priv->inet, m, meta);
+			break;
+		case NLPID_PPP:
+			m_adj(m, ptr - start);
+			NG_SEND_DATA(error, priv->ppp, m, meta);
+			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_SEND_DATA(error, priv->ppp, m, meta);
+			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_SEND_DATA(error, priv->downlink, m, meta);
+	} else if (hook == priv->inet) {
+		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;
+		NG_SEND_DATA(error, priv->downlink, m, meta);
+	} else
+		panic(__FUNCTION__);
+
+done:
+	NG_FREE_DATA(m, meta);
+	return (error);
+}
+
+/*
+ * Nuke node
+ */
+static int
+ng_rfc1490_rmnode(node_p node)
+{
+	const priv_p priv = node->private;
+
+	/* Take down netgraph node */
+	node->flags |= NG_INVALID;
+	ng_cutlinks(node);
+	ng_unname(node);
+	bzero(priv, sizeof(*priv));
+	node->private = NULL;
+	ng_unref(node);		/* let the node escape */
+	return (0);
+}
+
+/*
+ * Hook disconnection
+ */
+static int
+ng_rfc1490_disconnect(hook_p hook)
+{
+	const priv_p priv = hook->node->private;
+
+	if (hook->node->numhooks == 0)
+		ng_rmnode(hook->node);
+	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
+		panic(__FUNCTION__);
+	return (0);
+}
+