NetBSD/sys/netiso/clnp_options.c

/*	$NetBSD: clnp_options.c,v 1.17 2006/11/16 01:33:51 christos Exp $	*/

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON 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 ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)clnp_options.c	8.1 (Berkeley) 6/10/93
 */

/***********************************************************
		Copyright IBM Corporation 1987

                      All Rights Reserved

Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the name of IBM not be
used in advertising or publicity pertaining to distribution of the
software without specific, written prior permission.

IBM DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
IBM BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
SOFTWARE.

******************************************************************/

/*
 * ARGO Project, Computer Sciences Dept., University of Wisconsin - Madison
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: clnp_options.c,v 1.17 2006/11/16 01:33:51 christos Exp $");

#include "opt_iso.h"
#ifdef ISO

#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/systm.h>

#include <net/if.h>
#include <net/route.h>

#include <netiso/iso.h>
#include <netiso/clnp.h>
#include <netiso/clnp_stat.h>
#include <netiso/argo_debug.h>

/*
 * FUNCTION:		clnp_update_srcrt
 *
 * PURPOSE:		Process src rt option accompanying a clnp datagram.
 *			- bump src route ptr if src routing and
 *			we appear current in src route list.
 *
 * RETURNS:		none
 *
 * SIDE EFFECTS:
 *
 * NOTES:		If source routing has been terminated, do nothing.
 */
void
clnp_update_srcrt(
	struct mbuf *options,		/* ptr to options mbuf */
	struct clnp_optidx *oidx)	/* ptr to option index */
{
	u_char          len;	/* length of current address */
	struct iso_addr isoa;	/* copy current address into here */

	if (CLNPSRCRT_TERM(oidx, options)) {
#ifdef ARGO_DEBUG
		if (argo_debug[D_OPTIONS]) {
			printf("clnp_update_srcrt: src rt terminated\n");
		}
#endif
		return;
	}
	len = CLNPSRCRT_CLEN(oidx, options);
	bcopy(CLNPSRCRT_CADDR(oidx, options), (caddr_t) & isoa, len);
	isoa.isoa_len = len;

#ifdef ARGO_DEBUG
	if (argo_debug[D_OPTIONS]) {
		printf("clnp_update_srcrt: current src rt: %s\n",
		    clnp_iso_addrp(&isoa));
	}
#endif

	if (clnp_ours(&isoa)) {
#ifdef ARGO_DEBUG
		if (argo_debug[D_OPTIONS]) {
			printf("clnp_update_srcrt: updating src rt\n");
		}
#endif

		/* update pointer to next src route */
		len++;		/* count length byte too! */
		CLNPSRCRT_OFF(oidx, options) += len;
	}
}

/*
 * FUNCTION:		clnp_dooptions
 *
 * PURPOSE:		Process options accompanying a clnp datagram.
 *			Processing includes
 *			- log our address if recording route
 *
 * RETURNS:			none
 *
 * SIDE EFFECTS:
 *
 * NOTES:
 */
void
clnp_dooptions(
    struct mbuf *options,		/* ptr to options mbuf */
    struct clnp_optidx *oidx,		/* ptr to option index */
    struct ifnet *ifp,		/* ptr to interface pkt is leaving on */
    struct iso_addr *isoa)		/* ptr to our address for this ifp */
{
	/*
	 *	If record route is specified, move all
	 *	existing records over, and insert the address of
	 *	interface passed
	 */
	if (oidx->cni_recrtp) {
		char           *opt;	/* ptr to beginning of recrt option */
		u_char          off;	/* offset from opt of first free byte */
		char           *rec_start;	/* beginning of new rt
						 * recorded */

		opt = CLNP_OFFTOOPT(options, oidx->cni_recrtp);
		off = *(opt + 1);
		rec_start = opt + off - 1;

#ifdef ARGO_DEBUG
		if (argo_debug[D_OPTIONS]) {
			printf("clnp_dooptions: record route: option %p for %d bytes\n",
			    opt, oidx->cni_recrt_len);
			printf("\tfree slot offset x%x\n", off);
			printf("clnp_dooptions: recording %s\n", clnp_iso_addrp(isoa));
			printf("clnp_dooptions: option dump:\n");
			dump_buf(opt, oidx->cni_recrt_len);
		}
#endif

		/* proceed only if recording has not been terminated */
		if (off != 0xff) {
			int             new_addrlen = isoa->isoa_len + 1;
			/*
			 * if there is insufficient room to store the next
			 * address, then terminate recording. Plus 1 on
			 * isoa_len is for the length byte itself
			 */
			if (oidx->cni_recrt_len - (off - 1) < new_addrlen) {
				*(opt + 1) = 0xff;	/* terminate recording */
			} else {
#ifdef ARGO_DEBUG
				if (argo_debug[D_OPTIONS]) {
					printf("clnp_dooptions: new addr at %p for %d\n",
					       rec_start, new_addrlen);
				}
#endif

				bcopy((caddr_t) isoa, rec_start, new_addrlen);

				/* update offset field */
				*(opt + 1) += new_addrlen;

#ifdef ARGO_DEBUG
				if (argo_debug[D_OPTIONS]) {
					printf("clnp_dooptions: new option dump:\n");
					dump_buf(opt, oidx->cni_recrt_len);
				}
#endif
			}
		}
	}
}

/*
 * FUNCTION:		clnp_set_opts
 *
 * PURPOSE:		Check the data mbuf passed for option sanity. If it is
 *			ok, then set the options ptr to address the data mbuf.
 *			If an options mbuf exists, free it. This implies that
 *			any old options will be lost. If data is NULL, simply
 *			free any old options.
 *
 * RETURNS:		unix error code
 *
 * SIDE EFFECTS:
 *
 * NOTES:
 */
int
clnp_set_opts(
	struct mbuf **options,	/* target for option information */
	struct mbuf **data)	/* source of option information */
{
	int             error = 0;	/* error return value */
	struct clnp_optidx dummy;	/* dummy index - not used */

	/*
	 *	remove any existing options
	 */
	if (*options != NULL) {
		m_freem(*options);
		*options = NULL;
	}
	if (*data != NULL) {
		/*
		 *	Insure that the options are reasonable.
		 *
		 *	Also, we do not support security, priority,
		 *	nor do we allow one to send an ER option
		 *
		 *	The QOS parameter is checked for the DECBIT.
		 */
		if ((clnp_opt_sanity(*data, mtod(*data, caddr_t), (*data)->m_len,
				     &dummy) != 0) ||
		    (dummy.cni_securep) ||
		    (dummy.cni_priorp) ||
		    (dummy.cni_er_reason != ER_INVALREAS)) {
			error = EINVAL;
		} else {
			*options = *data;
			*data = NULL;	/* so caller won't free mbuf @ *data */
		}
	}
	return error;
}

/*
 * FUNCTION:		clnp_opt_sanity
 *
 * PURPOSE:		Check the options (beginning at opts for len bytes) for
 *			sanity. In addition, fill in the option index structure
 *			in with information about each option discovered.
 *
 * RETURNS:		success (options check out) - 0
 *			failure - an ER pdu error code describing failure
 *
 * SIDE EFFECTS:
 *
 * NOTES:		Each pointer field of the option index is filled in with
 *			the offset from the beginning of the mbuf data, not the
 *			actual address.
 */
int
clnp_opt_sanity(
	struct mbuf    *m,	/* mbuf options reside in */
	caddr_t         opts,	/* ptr to buffer containing options */
	int             len,	/* length of buffer */
	struct clnp_optidx *oidx)	/* RETURN: filled in with option idx
					 * info */
{
	u_char          opcode = 0;	/* code of particular option */
	u_char          oplen;	/* length of a particular option */
	caddr_t         opts_end;	/* ptr to end of options */
	u_char          pad = 0, secure = 0, srcrt = 0, recrt = 0,
			qos = 0, prior = 0;
	/* flags for catching duplicate options */

#ifdef ARGO_DEBUG
	if (argo_debug[D_OPTIONS]) {
		printf("clnp_opt_sanity: checking %d bytes of data:\n", len);
		dump_buf(opts, len);
	}
#endif

	/* clear option index field if passed */
	bzero((caddr_t) oidx, sizeof(struct clnp_optidx));

	/*
	 *	We need to indicate whether the ER option is present. This is done
	 *	by overloading the er_reason field to also indicate presence of
	 *	the option along with the option value. I would like ER_INVALREAS
	 *	to have value 0, but alas, 0 is a valid er reason...
	 */
	oidx->cni_er_reason = ER_INVALREAS;

	opts_end = opts + len;
	while (opts < opts_end) {
		/* must have at least 2 bytes per option (opcode and len) */
		if (opts + 2 > opts_end)
			return (GEN_INCOMPLETE);

		opcode = *opts++;
		oplen = *opts++;
#ifdef ARGO_DEBUG
		if (argo_debug[D_OPTIONS]) {
			printf("clnp_opt_sanity: opcode is %x and oplen %d\n",
			    opcode, oplen);
			printf("clnp_opt_sanity: clnpoval_SRCRT is %x\n", CLNPOVAL_SRCRT);

			switch (opcode) {
			case CLNPOVAL_PAD:
				printf("CLNPOVAL_PAD\n");
				break;
			case CLNPOVAL_SECURE:
				printf("CLNPOVAL_SECURE\n");
				break;
			case CLNPOVAL_SRCRT:
				printf("CLNPOVAL_SRCRT\n");
				break;
			case CLNPOVAL_RECRT:
				printf("CLNPOVAL_RECRT\n");
				break;
			case CLNPOVAL_QOS:
				printf("CLNPOVAL_QOS\n");
				break;
			case CLNPOVAL_PRIOR:
				printf("CLNPOVAL_PRIOR\n");
				break;
			case CLNPOVAL_ERREAS:
				printf("CLNPOVAL_ERREAS\n");
				break;
			default:
				printf("UNKNOWN option %x\n", opcode);
				break;
			}
		}
#endif

		/* don't allow crazy length values */
		if (opts + oplen > opts_end)
			return (GEN_INCOMPLETE);

		switch (opcode) {
		case CLNPOVAL_PAD:
			/*
			 *	Padding: increment pointer by length of padding
			 */
			if (pad++)	/* duplicate ? */
				return (GEN_DUPOPT);
			opts += oplen;
			break;

		case CLNPOVAL_SECURE:{
				u_char          format = *opts;

				if (secure++)	/* duplicate ? */
					return (GEN_DUPOPT);
				/*
				 *	Security: high 2 bits of first octet indicate format
				 *	(00 in high bits is reserved).
				 *	Remaining bits must be 0. Remaining octets indicate
				 *	actual security
				 */
				if (((format & 0x3f) > 0) ||	/* low 6 bits set ? */
				    ((format & 0xc0) == 0))	/* high 2 bits zero ? */
					return (GEN_HDRSYNTAX);

				oidx->cni_securep = CLNP_OPTTOOFF(m, opts);
				oidx->cni_secure_len = oplen;
				opts += oplen;
			} break;

		case CLNPOVAL_SRCRT:{
				u_char          type, offset;	/* type of rt, offset of
								 * start */
				caddr_t         route_end;	/* address of end of
								 * route option */

#ifdef ARGO_DEBUG
				if (argo_debug[D_OPTIONS]) {
					printf("clnp_opt_sanity: SRC RT\n");
				}
#endif

				if (srcrt++)	/* duplicate ? */
					return (GEN_DUPOPT);
				/*
				 * source route: There must be 2 bytes
				 * following the length field: type and
				 * offset. The type must be either partial
				 * route or complete route. The offset field
				 * must be within the option. A single
				 * exception is made, however. The offset may
				 * be 1 greater than the length. This case
				 * occurs when the last source route record
				 * is consumed. In this case, we ignore the
				 * source route option. RAH? You should be
				 * able to set offset to 'ff' like in record
				 * route! Following this is a series of
				 * address fields. Each address field is
				 * composed of a (length, address) pair.
				 * Insure that the offset and each address
				 * length is reasonable
				 */
				route_end = opts + oplen;

				if (opts + 2 > route_end)
					return (SRCRT_SYNTAX);

				type = *opts;
				offset = *(opts + 1);


				/* type must be partial or complete */
				if (!((type == CLNPOVAL_PARTRT) || (type == CLNPOVAL_COMPRT)))
					return (SRCRT_SYNTAX);

				oidx->cni_srcrt_s = CLNP_OPTTOOFF(m, opts);
				oidx->cni_srcrt_len = oplen;

				opts += offset - 1;	/* set opts to first
							 * addr in rt */

				/*
				 * Offset must be reasonable: less than end
				 * of options, or equal to end of options
				 */
				if (opts >= route_end) {
					if (opts == route_end) {
#ifdef ARGO_DEBUG
						if (argo_debug[D_OPTIONS]) {
							printf("clnp_opt_sanity: end of src route info\n");
						}
#endif
						break;
					} else
						return (SRCRT_SYNTAX);
				}
				while (opts < route_end) {
					u_char          addrlen = *opts++;
					if (opts + addrlen > route_end)
						return (SRCRT_SYNTAX);
					opts += addrlen;
				}
			} break;
		case CLNPOVAL_RECRT:{
				u_char          type, offset;	/* type of rt, offset of
								 * start */
				caddr_t         record_end;	/* address of end of
								 * record option */

				if (recrt++)	/* duplicate ? */
					return (GEN_DUPOPT);
				/*
				 *	record route: after the length field, expect a
				 *	type and offset. Type must be partial or complete.
				 *	Offset indicates where to start recording. Insure it
				 *	is within the option. All ones for offset means
				 *	recording is terminated.
				 */
				record_end = opts + oplen;

				oidx->cni_recrtp = CLNP_OPTTOOFF(m, opts);
				oidx->cni_recrt_len = oplen;

				if (opts + 2 > record_end)
					return (GEN_INCOMPLETE);

				type = *opts;
				offset = *(opts + 1);

				/* type must be partial or complete */
				if (!((type == CLNPOVAL_PARTRT) || (type == CLNPOVAL_COMPRT)))
					return (GEN_HDRSYNTAX);

				/* offset must be reasonable */
				if ((offset < 0xff) && (opts + offset > record_end))
					return (GEN_HDRSYNTAX);
				opts += oplen;
			} break;
		case CLNPOVAL_QOS:{
				u_char          format = *opts;

				if (qos++)	/* duplicate ? */
					return (GEN_DUPOPT);
				/*
				 *	qos: high 2 bits of first octet indicate format
				 *	(00 in high bits is reserved).
				 *	Remaining bits must be 0 (unless format indicates
				 *	globally unique qos, in which case remaining bits indicate
				 *	qos (except bit 6 which is reserved)).  Otherwise,
				 *	remaining octets indicate actual qos.
				 */
				if (((format & 0xc0) == 0) ||	/* high 2 bits zero ? */
				    (((format & 0xc0) != CLNPOVAL_GLOBAL) &&
				     ((format & 0x3f) > 0)))	/* not global,low bits
								 * used ? */
					return (GEN_HDRSYNTAX);

				oidx->cni_qos_formatp = CLNP_OPTTOOFF(m, opts);
				oidx->cni_qos_len = oplen;

				opts += oplen;
			} break;

		case CLNPOVAL_PRIOR:{
				if (prior++)	/* duplicate ? */
					return (GEN_DUPOPT);
				/*
				 *	priority: value must be one byte long
				 */
				if (oplen != 1)
					return (GEN_HDRSYNTAX);

				oidx->cni_priorp = CLNP_OPTTOOFF(m, opts);

				opts += oplen;
			} break;

		case CLNPOVAL_ERREAS:{
				/*
				 *	er reason: value must be two bytes long
				 */
				if (oplen != 2)
					return (GEN_HDRSYNTAX);

				oidx->cni_er_reason = *opts;

				opts += oplen;
			} break;

		default:{
#ifdef ARGO_DEBUG
				if (argo_debug[D_OPTIONS]) {
					printf("clnp_opt_sanity: UNKNOWN OPTION 0x%x\n", opcode);
				}
#endif
				return (DISC_UNSUPPOPT);
			}
		}
	}
#ifdef ARGO_DEBUG
	if (argo_debug[D_OPTIONS]) {
		printf("clnp_opt_sanity: return(0)\n");
	}
#endif
	return (0);
}
#endif /* ISO */