NetBSD/sys/netinet6/ipcomp_input.c

395 lines
9.2 KiB
C

/* $NetBSD: ipcomp_input.c,v 1.4 1999/07/06 05:09:22 itojun Exp $ */
/*
* Copyright (C) 1999 WIDE Project.
* 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 project 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 PROJECT 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 PROJECT 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.
*/
/*
* RFC2393 IP payload compression protocol (IPComp).
*/
#if (defined(__FreeBSD__) && __FreeBSD__ >= 3) || defined(__NetBSD__)
#include "opt_inet.h"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/route.h>
#include <net/netisr.h>
#include <net/zlib.h>
#include <machine/cpu.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/ip_ecn.h>
#ifdef INET6
#include <netinet6/in6_systm.h>
#include <netinet6/ip6.h>
#if !defined(__FreeBSD__) || __FreeBSD__ < 3
#include <netinet6/in6_pcb.h>
#endif
#include <netinet6/ip6_var.h>
#endif
#include <netinet6/ipcomp.h>
#include <netinet6/ipsec.h>
#include <netkey/key.h>
#include <netkey/keydb.h>
#include <netkey/key_debug.h>
#include <machine/stdarg.h>
#define IPLEN_FLIPPED
#ifdef __NetBSD__
#define ovbcopy bcopy
#endif
#ifdef INET
extern struct protosw inetsw[];
#if defined(__bsdi__) || defined(__NetBSD__)
extern u_char ip_protox[];
#endif
void
#if __STDC__
ipcomp4_input(struct mbuf *m, ...)
#else
ipcomp4_input(m, va_alist)
struct mbuf *m;
va_dcl
#endif
{
struct ip *ip;
struct ipcomp *ipcomp;
struct ipcomp_algorithm *algo;
u_int16_t cpi; /* host order */
u_int16_t nxt;
size_t hlen;
int error;
size_t newlen, olen;
struct secas *sa = NULL;
int off, proto;
va_list ap;
va_start(ap, m);
off = va_arg(ap, int);
proto = va_arg(ap, int);
va_end(ap);
if (off + sizeof(struct ipcomp) > MHLEN) {
/*XXX the restriction should be relaxed*/
printf("IPv4 IPComp input: assumption failed (header too long)\n");
goto fail;
}
if (m->m_len < off + sizeof(struct ipcomp)) {
m = m_pullup(m, off + sizeof(struct ipcomp));
if (!m) {
printf("IPv4 IPComp input: can't pullup;"
"dropping the packet for simplicity\n");
ipsecstat.in_inval++;
goto fail;
}
} else if (m->m_len > off + sizeof(struct ipcomp)) {
/* chop header part from the packet header chain */
struct mbuf *n;
MGETHDR(n, M_DONTWAIT, MT_HEADER);
if (!n)
goto fail;
M_COPY_PKTHDR(n, m);
MH_ALIGN(n, off + sizeof(struct ipcomp));
n->m_len = off + sizeof(struct ipcomp);
bcopy(mtod(m, caddr_t), mtod(n, caddr_t),
off + sizeof(struct ipcomp));
m_adj(m, off + sizeof(struct ipcomp));
m->m_flags &= ~M_PKTHDR;
n->m_next = m;
m = n;
}
ip = mtod(m, struct ip *);
ipcomp = (struct ipcomp *)(((caddr_t)ip) + off);
nxt = ipcomp->comp_nxt;
#ifdef _IP_VHL
hlen = IP_VHL_HL(ip->ip_vhl) << 2;
#else
hlen = ip->ip_hl << 2;
#endif
cpi = ntohs(ipcomp->comp_cpi);
if (cpi >= IPCOMP_CPI_NEGOTIATE_MIN) {
sa = key_allocsa(AF_INET, (caddr_t)&ip->ip_src,
(caddr_t)&ip->ip_dst, IPPROTO_IPCOMP, htonl(cpi));
if (sa != NULL
&& (sa->state == SADB_SASTATE_MATURE
|| sa->state == SADB_SASTATE_DYING)) {
cpi = sa->alg_enc; /*XXX*/
/* other parameters to look at? */
}
}
if (cpi < IPCOMP_MAX || ipcomp_algorithms[cpi].decompress != NULL)
algo = &ipcomp_algorithms[cpi];
else
algo = NULL;
if (!algo) {
printf("IPv4 IPComp input: unknown cpi %u; "
"dropping the packet for simplicity\n", cpi);
ipsecstat.in_nosa++;
goto fail;
}
/* chop ipcomp header */
ipcomp = NULL;
m->m_len -= sizeof(struct ipcomp);
m->m_pkthdr.len -= sizeof(struct ipcomp);
#ifdef IPLEN_FLIPPED
ip->ip_len -= sizeof(struct ipcomp);
#else
ip->ip_len = htons(ntohs(ip->ip_len) - sizeof(struct ipcomp));
#endif
olen = m->m_pkthdr.len;
newlen = m->m_pkthdr.len - off;
error = (*algo->decompress)(m, m->m_next, &newlen);
if (error != 0) {
m = NULL;
goto fail;
}
/*
* returning decompressed packet onto icmp is meaningless.
* mark it decrypted to prevent icmp from attaching original packet.
*/
m->m_flags |= M_DECRYPTED;
m->m_pkthdr.len = off + newlen;
ip = mtod(m, struct ip *);
{
size_t len;
#ifdef IPLEN_FLIPPED
len = ip->ip_len;
#else
len = ntohs(ip->ip_len);
#endif
/*
* be careful about underflow. also, do not assign exact value
* as ip_len is manipulated differently on *BSDs.
*/
len += m->m_pkthdr.len;
len -= olen;
if (len & ~0xffff) {
/* packet too big after decompress */
ipsecstat.in_inval++;
goto fail;
}
#ifdef IPLEN_FLIPPED
ip->ip_len = len & 0xffff;
#else
ip->ip_len = htons(len & 0xffff);
#endif
ip->ip_p = nxt;
}
if (sa) {
key_sa_recordxfer(sa, m);
key_freesa(sa);
sa = NULL;
}
if (nxt != IPPROTO_DONE)
(*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt);
else
m_freem(m);
m = NULL;
ipsecstat.in_success++;
return;
fail:
if (sa)
key_freesa(sa);
if (m)
m_freem(m);
return;
}
#endif /* INET */
#ifdef INET6
int
ipcomp6_input(mp, offp, proto)
struct mbuf **mp;
int *offp, proto;
{
struct mbuf *m, *md;
int off;
struct ip6_hdr *ip6;
struct mbuf *ipcompm;
struct ipcomp *ipcomp;
struct ipcomp_algorithm *algo;
u_int16_t cpi; /* host order */
u_int16_t nxt;
int error;
size_t newlen;
struct secas *sa = NULL;
m = *mp;
off = *offp;
IP6_EXTHDR_CHECK(m, off, sizeof(struct ipcomp), IPPROTO_DONE);
{
int skip;
struct mbuf *n;
struct mbuf *p, *q;
size_t l;
skip = off;
for (n = m; n && skip > 0; n = n->m_next) {
if (n->m_len <= skip) {
skip -= n->m_len;
continue;
}
break;
}
if (!n) {
printf("IPv6 IPComp input: wrong mbuf chain\n");
goto fail;
}
if (n->m_len < skip + sizeof(struct ipcomp)) {
printf("IPv6 IPComp input: wrong mbuf chain\n");
goto fail;
}
ip6 = mtod(m, struct ip6_hdr *);
ipcompm = n;
ipcomp = (struct ipcomp *)(mtod(n, caddr_t) + skip);
if (n->m_len > skip + sizeof(struct ipcomp)) {
/* split mbuf to ease the following steps*/
l = n->m_len - (skip + sizeof(struct ipcomp));
p = m_copym(n, skip + sizeof(struct ipcomp), l , M_DONTWAIT);
if (!p)
goto fail;
for (q = p; q && q->m_next; q = q->m_next)
;
q->m_next = n->m_next;
n->m_next = p;
n->m_len -= l;
md = p;
} else
md = n->m_next;
}
nxt = ipcomp->comp_nxt;
cpi = ntohs(ipcomp->comp_cpi);
if (cpi >= IPCOMP_CPI_NEGOTIATE_MIN) {
sa = key_allocsa(AF_INET6, (caddr_t)&ip6->ip6_src,
(caddr_t)&ip6->ip6_dst, IPPROTO_IPCOMP, htonl(cpi));
if (sa != NULL
&& (sa->state == SADB_SASTATE_MATURE
|| sa->state == SADB_SASTATE_DYING)) {
cpi = sa->alg_enc; /*XXX*/
/* other parameters to look at? */
}
}
if (cpi < IPCOMP_MAX || ipcomp_algorithms[cpi].decompress != NULL)
algo = &ipcomp_algorithms[cpi];
else
algo = NULL;
if (!algo) {
printf("IPv6 IPComp input: unknown cpi %u; "
"dropping the packet for simplicity\n", cpi);
ipsec6stat.in_nosa++;
goto fail;
}
newlen = m->m_pkthdr.len - off - sizeof(struct ipcomp);
error = (*algo->decompress)(m, md, &newlen);
if (error != 0) {
m = NULL;
goto fail;
}
m->m_pkthdr.len = off + sizeof(struct ipcomp) + newlen;
/*
* returning decompressed packet onto icmp is meaningless.
* mark it decrypted to prevent icmp from attaching original packet.
*/
m->m_flags |= M_DECRYPTED;
{
char *prvnxtp;
/* chop IPComp header */
prvnxtp = ip6_get_prevhdr(m, off);
*prvnxtp = nxt;
ipcompm->m_len -= sizeof(struct ipcomp);
ipcompm->m_pkthdr.len -= sizeof(struct ipcomp);
/* adjust payload length */
ip6 = mtod(m, struct ip6_hdr *);
if (((m->m_pkthdr.len - sizeof(struct ip6_hdr)) & ~0xffff) != 0)
ip6->ip6_plen = 0; /*now a jumbogram*/
else
ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
}
if (sa) {
key_sa_recordxfer(sa, m);
key_freesa(sa);
sa = NULL;
}
*offp = off;
*mp = m;
ipsec6stat.in_success++;
return nxt;
fail:
if (m)
m_freem(m);
if (sa)
key_freesa(sa);
return IPPROTO_DONE;
}
#endif /* INET6 */