GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/net/ip6opt.c Lines: 0 95 0.0 %
Date: 2017-11-13 Branches: 0 77 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: ip6opt.c,v 1.9 2017/04/27 23:52:35 millert Exp $	*/
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/*	$KAME: ip6opt.c,v 1.18 2005/06/15 07:11:35 keiichi Exp $	*/
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/*
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 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
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 * All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the project nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <netinet/in.h>
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#include <netinet/ip6.h>
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#include <string.h>
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#include <stdio.h>
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static int ip6optlen(u_int8_t *opt, u_int8_t *lim);
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/*
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 * Calculate the length of a given IPv6 option. Also checks
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 * if the option is safely stored in user's buffer according to the
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 * calculated length and the limitation of the buffer.
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 */
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static int
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ip6optlen(u_int8_t *opt, u_int8_t *lim)
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{
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	int optlen;
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	if (*opt == IP6OPT_PAD1)
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		optlen = 1;
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	else {
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		/* is there enough space to store type and len? */
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		if (opt + 2 > lim)
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			return (0);
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		optlen = *(opt + 1) + 2;
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	}
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	if (opt + optlen <= lim)
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		return (optlen);
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	return (0);
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}
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/*
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 * The following functions are defined in RFC3542, which is a successor
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 * of RFC2292.
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 */
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int
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inet6_opt_init(void *extbuf, socklen_t extlen)
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{
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	struct ip6_ext *ext = (struct ip6_ext *)extbuf;
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	if (ext) {
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		if (extlen <= 0 || (extlen % 8))
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			return (-1);
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		ext->ip6e_len = (extlen >> 3) - 1;
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	}
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	return (2);		/* sizeof the next and the length fields */
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}
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int
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inet6_opt_append(void *extbuf, socklen_t extlen, int offset, u_int8_t type,
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		 socklen_t len, u_int8_t align, void **databufp)
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{
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	int currentlen = offset, padlen = 0;
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	/*
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	 * The option type must have a value from 2 to 255, inclusive.
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	 * (0 and 1 are reserved for the Pad1 and PadN options, respectively.)
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	 */
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#if 0 /* always false */
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	if (type < 2 || type > 255)
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#else
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	if (type < 2)
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#endif
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		return (-1);
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	/*
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	 * The option data length must have a value between 0 and 255,
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	 * inclusive, and is the length of the option data that follows.
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	 */
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	if (len > 255)
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		return (-1);
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	/*
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	 * The align parameter must have a value of 1, 2, 4, or 8.
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	 * The align value can not exceed the value of len.
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	 */
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	if (align != 1 && align != 2 && align != 4 && align != 8)
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		return (-1);
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	if (align > len)
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		return (-1);
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	/* Calculate the padding length. */
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	currentlen += 2 + len;	/* 2 means "type + len" */
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	if (currentlen % align)
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		padlen = align - (currentlen % align);
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	/* The option must fit in the extension header buffer. */
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	currentlen += padlen;
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	if (extlen &&		/* XXX: right? */
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	    currentlen > extlen)
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		return (-1);
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	if (extbuf) {
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		u_int8_t *optp = (u_int8_t *)extbuf + offset;
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		if (padlen == 1) {
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			/* insert a Pad1 option */
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			*optp = IP6OPT_PAD1;
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			optp++;
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		} else if (padlen > 0) {
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			/* insert a PadN option for alignment */
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			*optp++ = IP6OPT_PADN;
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			*optp++ = padlen - 2;
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			memset(optp, 0, padlen - 2);
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			optp += (padlen - 2);
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		}
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		*optp++ = type;
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		*optp++ = len;
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		*databufp = optp;
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	}
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	return (currentlen);
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}
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int
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inet6_opt_finish(void *extbuf, socklen_t extlen, int offset)
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{
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	int updatelen = offset > 0 ? (1 + ((offset - 1) | 7)) : 0;;
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	if (extbuf) {
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		u_int8_t *padp;
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		int padlen = updatelen - offset;
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		if (updatelen > extlen)
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			return (-1);
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		padp = (u_int8_t *)extbuf + offset;
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		if (padlen == 1)
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			*padp = IP6OPT_PAD1;
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		else if (padlen > 0) {
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			*padp++ = IP6OPT_PADN;
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			*padp++ = (padlen - 2);
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			memset(padp, 0, padlen - 2);
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		}
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	}
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	return (updatelen);
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}
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int
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inet6_opt_set_val(void *databuf, int offset, void *val, socklen_t vallen)
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{
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	memcpy((u_int8_t *)databuf + offset, val, vallen);
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	return (offset + vallen);
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}
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int
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inet6_opt_next(void *extbuf, socklen_t extlen, int offset, u_int8_t *typep,
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	       socklen_t *lenp, void **databufp)
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{
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	u_int8_t *optp, *lim;
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	int optlen;
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	/* Validate extlen. XXX: is the variable really necessary?? */
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	if (extlen == 0 || (extlen % 8))
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		return (-1);
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	lim = (u_int8_t *)extbuf + extlen;
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	/*
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	 * If this is the first time this function called for this options
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	 * header, simply return the 1st option.
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	 * Otherwise, search the option list for the next option.
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	 */
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	if (offset == 0)
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		optp = (u_int8_t *)((struct ip6_hbh *)extbuf + 1);
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	else
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		optp = (u_int8_t *)extbuf + offset;
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	/* Find the next option skipping any padding options. */
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	while (optp < lim) {
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		switch(*optp) {
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		case IP6OPT_PAD1:
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			optp++;
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			break;
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		case IP6OPT_PADN:
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			if ((optlen = ip6optlen(optp, lim)) == 0)
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				goto optend;
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			optp += optlen;
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			break;
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		default:	/* found */
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			if ((optlen = ip6optlen(optp, lim)) == 0)
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				goto optend;
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			*typep = *optp;
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			*lenp = optlen - 2;
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			*databufp = optp + 2;
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			return (optp + optlen - (u_int8_t *)extbuf);
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		}
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	}
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  optend:
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	*databufp = NULL; /* for safety */
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	return (-1);
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}
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int
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inet6_opt_find(void *extbuf, socklen_t extlen, int offset, u_int8_t type,
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	       socklen_t *lenp, void **databufp)
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{
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	u_int8_t *optp, *lim;
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	int optlen;
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	/* Validate extlen. XXX: is the variable really necessary?? */
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	if (extlen == 0 || (extlen % 8))
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		return (-1);
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	lim = (u_int8_t *)extbuf + extlen;
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	/*
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	 * If this is the first time this function called for this options
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	 * header, simply return the 1st option.
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	 * Otherwise, search the option list for the next option.
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	 */
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	if (offset == 0)
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		optp = (u_int8_t *)((struct ip6_hbh *)extbuf + 1);
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	else
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		optp = (u_int8_t *)extbuf + offset;
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	/* Find the specified option */
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	while (optp < lim) {
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		if ((optlen = ip6optlen(optp, lim)) == 0)
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			goto optend;
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		if (*optp == type) { /* found */
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			*lenp = optlen - 2;
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			*databufp = optp + 2;
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			return (optp + optlen - (u_int8_t *)extbuf);
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		}
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		optp += optlen;
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	}
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  optend:
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	*databufp = NULL; /* for safety */
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	return (-1);
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}
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int
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inet6_opt_get_val(void *databuf, int offset, void *val, socklen_t vallen)
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{
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	/* we can't assume alignment here */
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	memcpy(val, (u_int8_t *)databuf + offset, vallen);
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	return (offset + vallen);
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}