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/* $OpenBSD: ip_ah.c,v 1.7 1997/07/01 22:12:41 provos Exp $ */
/*
* The author of this code is John Ioannidis, ji@tla.org,
* (except when noted otherwise).
*
* This code was written for BSD/OS in Athens, Greece, in November 1995.
*
* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
* by Angelos D. Keromytis, kermit@forthnet.gr.
*
* Copyright (C) 1995, 1996, 1997 by John Ioannidis and Angelos D. Keromytis.
*
* Permission to use, copy, and modify this software without fee
* is hereby granted, provided that this entire notice is included in
* all copies of any software which is or includes a copy or
* modification of this software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NEITHER AUTHOR MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
/*
* Authentication Header Processing
* Per RFC1826 (Atkinson, 1995)
*/
#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 <machine/cpu.h>
#include <net/if.h>
#include <net/route.h>
#include <net/netisr.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#include <netinet/ip_icmp.h>
#include <sys/socketvar.h>
#include <net/raw_cb.h>
#include <net/encap.h>
#include <netinet/ip_ipsp.h>
#include <netinet/ip_ah.h>
void ah_input __P((struct mbuf *, int));
/*
* ah_input gets called when we receive an packet with an AH.
*/
void
ah_input(register struct mbuf *m, int iphlen)
{
struct ip *ipo;
struct ah *ahp;
struct tdb *tdbp;
struct ifqueue *ifq = NULL;
int s;
ahstat.ahs_input++;
#if 0 /* We need them to verify the packet */
/*
* Strip IP options, if any.
*/
if (iphlen > sizeof (struct ip))
{
ip_stripoptions(m, (struct mbuf *)0);
iphlen = sizeof (struct ip);
}
#endif
/*
* Make sure that at least the fixed part of the AH header is
* in the first mbuf.
*/
ipo = mtod(m, struct ip *);
if (m->m_len < iphlen + AH_FLENGTH)
{
if ((m = m_pullup(m, iphlen + AH_FLENGTH)) == 0)
{
ahstat.ahs_hdrops++;
return;
}
ipo = mtod(m, struct ip *);
}
ahp = (struct ah *)((caddr_t)ipo + iphlen);
/*
* Find tunnel control block and (indirectly) call the appropriate
* tranform routine. The resulting mbuf chain is a valid
* IP packet ready to go through input processing.
*/
tdbp = gettdb(ahp->ah_spi, ipo->ip_dst);
if (tdbp == NULL)
{
#ifdef ENCDEBUG
if (encdebug)
printf("ah_input: no tdb for spi=%x\n", ahp->ah_spi);
#endif ENCDEBUG
m_freem(m);
ahstat.ahs_notdb++;
return;
}
if (tdbp->tdb_flags & TDBF_INVALID)
{
#ifdef ENCDEBUG
if (encdebug)
printf("ah_input: spi=%x is no longer/yet valid\n", ahp->ah_spi);
#endif /* ENCDEBUG */
m_freem(m);
ahstat.ahs_invalid++;
return;
}
if (tdbp->tdb_xform == NULL)
{
#ifdef ENCDEBUG
if (encdebug)
printf("ah_input: no xform for spi=%x\n", ahp->ah_spi);
#endif ENCDEBUG
m_freem(m);
ahstat.ahs_noxform++;
return;
}
m->m_pkthdr.rcvif = &enc_softc;
/* Register first use */
if (tdbp->tdb_first_use == 0)
tdbp->tdb_first_use = time.tv_sec;
m = (*(tdbp->tdb_xform->xf_input))(m, tdbp);
if (m == NULL)
{
ahstat.ahs_badkcr++;
return;
}
/*
* Interface pointer is already in first mbuf; chop off the
* `outer' header and reschedule.
*/
ifq = &ipintrq;
s = splimp(); /* isn't it already? */
if (IF_QFULL(ifq))
{
IF_DROP(ifq);
m_freem(m);
ahstat.ahs_qfull++;
splx(s);
return;
}
IF_ENQUEUE(ifq, m);
schednetisr(NETISR_IP);
splx(s);
return;
}
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