blob: f6c1ecffcb1b6453f5864aee2a8150581802981d [file] [log] [blame] [raw]
/*
* Copyright (C) 1993-2003 by Darren Reed.
*
* See the IPFILTER.LICENCE file for details on licencing.
*/
#if !defined(lint)
static const char sccsid[] = "@(#)ip_fil.c 2.41 6/5/96 (C) 1993-2000 Darren Reed";
static const char rcsid[] = "@(#)$Id$";
#endif
#if defined(KERNEL) || defined(_KERNEL)
# undef KERNEL
# undef _KERNEL
# define KERNEL 1
# define _KERNEL 1
#endif
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/types.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/systm.h>
#include <sys/dir.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if.h>
#include <sys/debug.h>
#ifdef IFF_DRVRLOCK /* IRIX6 */
# include <sys/hashing.h>
#endif
#include <net/route.h>
#include <netinet/in.h>
#if !defined(IFF_DRVRLOCK) /* IRIX < 6 */
# include <netinet/in_var.h>
#endif
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_timer.h>
#include <netinet/udp.h>
#include <netinet/tcpip.h>
#include <netinet/ip_icmp.h>
#include "netinet/ip_compat.h"
#ifdef USE_INET6
# include <netinet/icmp6.h>
#endif
#include "netinet/ip_fil.h"
#include "netinet/ip_nat.h"
#include "netinet/ip_frag.h"
#include "netinet/ip_state.h"
#include "netinet/ip_proxy.h"
#include "netinet/ip_auth.h"
#include "netinet/ip_sync.h"
#ifdef IPFILTER_SCAN
#include "netinet/ip_scan.h"
#endif
#include "md5.h"
extern int tcp_mtudisc;
extern int ipforwarding;
extern struct protosw inetsw[];
extern int tcp_ttl;
#if IRIX >= 60500
extern toid_t ipf_timer_id;
#endif
static int (*ipf_savep)(ip_t *, int, void *, int, struct mbuf **);
static int ipf_send_ip(fr_info_t *, struct mbuf *, struct mbuf **);
static int ipfopen(dev_t *, int, int, cred_t *);
static int ipfclose(dev_t *, int, int, cred_t *);
static int ipfread(dev_t, struct uio *, cred_t *);
int
ipf_attach()
{
int error = 0, s;
SPL_NET(s);
if (ipf_running > 0) {
SPL_X(s);
return EBUSY;
}
if (ipf_initialise() < 0)
return -1;
error = ipf_ipfilter_attach();
if (error) {
ipf_deinitialise();
SPL_X(s);
return error;
}
if (ipf_checkp != ipf_check) {
ipf_savep = ipf_checkp;
ipf_checkp = ipf_check;
}
if (ipf_control_forwarding & 1)
ipforwarding = 1;
SPL_X(s);
#if IRIX >= 60500
ipf_timer_id = timeout(ipf_slowtimer, &ipfmain, hz/2);
#else
timeout(ipf_slowtimer, &ipfmain, hz/2);
#endif
return 0;
}
/*
* Disable the filter by removing the hooks from the IP input/output
* stream.
*/
int
ipf_detach()
{
int s, error = 0;
SPL_NET(s);
#if IRIX >= 60500
if (ipf_timer_id != 0) {
/* error = untimeout(ipf_timer_id); XXX - does not work with */
/* timeout() return value, only itimeout() and dtimeout(). */
ipf_timer_id = 0;
}
#else
untimeout(ipf_slowtimer);
#endif
if (ipf_control_forwarding & 2)
ipforwarding = 0;
ipf_deinitialise();
if (ipf_savep != NULL)
ipf_checkp = ipf_savep;
ipf_savep = NULL;
(void) frflush(&ipfmain, IPL_LOGIPF, FR_INQUE|FR_OUTQUE|FR_INACTIVE);
(void) frflush(&ipfmain, IPL_LOGIPF, FR_INQUE|FR_OUTQUE);
ipf_ipfilter_detach();
SPL_X(s);
return 0;
}
/*
* Filter ioctl interface.
*/
int
ipfioctl(dev, cmd, data, mode, cp, rp)
dev_t dev;
int cmd;
caddr_t data;
int mode;
cred_t *cp;
int *rp;
{
int error = 0, unit = 0;
SPL_INT(s);
unit = GET_MINOR(dev);
if ((IPL_LOGMAX < unit) || (unit < 0)) {
ipfmain.ipf_interror = 130002;
return ENXIO;
}
if (ipf_running <= 0) {
if (unit != IPL_LOGIPF) {
ipfmain.ipf_interror = 130003;
return EIO;
}
if (cmd != SIOCIPFGETNEXT && cmd != SIOCIPFGET &&
cmd != SIOCIPFSET && cmd != SIOCFRENB &&
cmd != SIOCGETFS && cmd != SIOCGETFF &&
cmd != SIOCIPFINTERROR) {
ipfmain.ipf_interror = 130004;
return EIO;
}
}
SPL_NET(s);
error = ipf_ioctlswitch(&ipfmain, unit, data, cmd, mode,
cp->cr_uid, curproc);
if (error != -1) {
SPL_X(s);
return error;
}
error = 0;
SPL_X(s);
return error;
}
/*
* routines below for saving IP headers to buffer
*/
static int
ipfopen(pdev, flags, devtype, cp)
dev_t *pdev;
int flags, devtype;
cred_t *cp;
{
u_int unit = geteminor(*pdev);
int error;
if (IPL_LOGMAX < unit) {
error = ENXIO;
} else {
switch (unit)
{
case IPL_LOGIPF :
case IPL_LOGNAT :
case IPL_LOGSTATE :
case IPL_LOGAUTH :
case IPL_LOGLOOKUP :
case IPL_LOGSYNC :
#ifdef IPFILTER_SCAN
case IPL_LOGSCAN :
#endif
error = 0;
break;
default :
error = ENXIO;
break;
}
}
return error;
}
static int
ipfclose(dev, flags, devtype, cp)
dev_t dev;
int flags, devtype;
cred_t *cp;
{
u_int unit = GET_MINOR(dev);
if (IPL_LOGMAX < unit)
unit = ENXIO;
else
unit = 0;
return unit;
}
/*
* ipfread/ipflog
* both of these must operate with at least splnet() lest they be
* called during packet processing and cause an inconsistancy to appear in
* the filter lists.
*/
static int
ipfread(dev, uio, crp)
dev_t dev;
register struct uio *uio;
cred_t *crp;
{
if (ipf_running < 1) {
ipfmain.ipf_interror = 130006;
return EIO;
}
#ifdef IPFILTER_LOG
return ipflog_read(GET_MINOR(dev), uio);
#else
ipfmain.ipf_interror = 130007;
return ENXIO;
#endif
}
/*
* ipf_send_reset - this could conceivably be a call to tcp_respond(), but that
* requires a large amount of setting up and isn't any more efficient.
*/
int
ipf_send_reset(fin)
fr_info_t *fin;
{
struct tcphdr *tcp, *tcp2;
int tlen = 0, hlen;
struct mbuf *m;
#ifdef USE_INET6
ip6_t *ip6;
#endif
ip_t *ip;
tcp = fin->fin_dp;
if (tcp->th_flags & TH_RST)
return -1; /* feedback loop */
if (ipf_checkl4sum(fin) == -1)
return -1;
m = m_get(M_DONTWAIT, MT_HEADER);
if (m == NULL)
return -1;
tlen = fin->fin_dlen - (TCP_OFF(tcp) << 2) +
((tcp->th_flags & TH_SYN) ? 1 : 0) +
((tcp->th_flags & TH_FIN) ? 1 : 0);
#ifdef USE_INET6
hlen = (fin->fin_v == 6) ? sizeof(ip6_t) : sizeof(ip_t);
#else
hlen = sizeof(ip_t);
#endif
m->m_len = sizeof(*tcp2) + hlen;
# if (BSD >= 199103)
m->m_data += max_linkhdr;
m->m_pkthdr.len = m->m_len;
m->m_pkthdr.rcvif = (struct ifnet *)0;
# endif
ip = mtod(m, struct ip *);
bzero((char *)ip, hlen);
# ifdef USE_INET6
ip6 = (ip6_t *)ip;
# endif
tcp2 = (struct tcphdr *)((char *)ip + hlen);
tcp2->th_sport = tcp->th_dport;
tcp2->th_dport = tcp->th_sport;
if (tcp->th_flags & TH_ACK) {
tcp2->th_seq = tcp->th_ack;
tcp2->th_flags = TH_RST;
tcp2->th_ack = 0;
} else {
tcp2->th_seq = 0;
tcp2->th_ack = ntohl(tcp->th_seq);
tcp2->th_ack += tlen;
tcp2->th_ack = htonl(tcp2->th_ack);
tcp2->th_flags = TH_RST|TH_ACK;
}
TCP_X2_A(tcp2, 0);
TCP_OFF_A(tcp2, sizeof(*tcp2) >> 2);
tcp2->th_win = tcp->th_win;
tcp->th_sum = 0;
tcp->th_urp = 0;
# ifdef USE_INET6
if (fin->fin_v == 6) {
ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
ip6->ip6_plen = htons(sizeof(struct tcphdr));
ip6->ip6_nxt = IPPROTO_TCP;
ip6->ip6_hlim = 0;
ip6->ip6_src = fin->fin_dst6;
ip6->ip6_dst = fin->fin_src6;
tcp2->th_sum = in6_cksum(m, IPPROTO_TCP,
sizeof(*ip6), sizeof(*tcp2));
return ipf_send_ip(fin, m, &m);
}
# endif
ip->ip_p = IPPROTO_TCP;
ip->ip_len = htons(sizeof(struct tcphdr));
ip->ip_src.s_addr = fin->fin_daddr;
ip->ip_dst.s_addr = fin->fin_saddr;
tcp2->th_sum = in_cksum(m, hlen + sizeof(*tcp2));
ip->ip_len = hlen + sizeof(*tcp2);
return ipf_send_ip(fin, m, &m);
}
static int
ipf_send_ip(fin, m, mpp)
fr_info_t *fin;
struct mbuf *m, **mpp;
{
fr_info_t fnew;
ip_t *ip;
int hlen;
ip = mtod(m, ip_t *);
bzero((char *)&fnew, sizeof(fnew));
IP_V_A(ip, fin->fin_v);
switch (fin->fin_v)
{
case 4 :
fnew.fin_v = 4;
IP_HL_A(ip, sizeof(ip_t) >> 2);
ip->ip_tos = fin->fin_ip->ip_tos;
ip->ip_id = fin->fin_ip->ip_id;
if (ip->ip_p == IPPROTO_TCP && tcp_mtudisc != 0)
ip->ip_off = htons(IP_DF);
ip->ip_ttl = tcp_ttl;
ip->ip_sum = 0;
ip->ip_len = htons(ip->ip_len);
hlen = sizeof(*ip);
break;
#ifdef USE_INET6
case 6 :
{
ip6_t *ip6 = (ip6_t *)ip;
ip6->ip6_hlim = 127;
m = *mpp;
*mpp = NULL;
return ip6_output(m, NULL, NULL, 0, NULL, NULL);
}
#endif
default :
return EINVAL;
}
#ifdef IPSEC
m->m_pkthdr.rcvif = NULL;
#endif
fnew.fin_ifp = fin->fin_ifp;
fnew.fin_flx = FI_NOCKSUM;
fnew.fin_m = m;
fnew.fin_ip = ip;
fnew.fin_mp = mpp;
fnew.fin_hlen = hlen;
fnew.fin_dp = (char *)ip + hlen;
(void) ipf_makefrip(hlen, ip, &fnew);
if (fin->fin_fr != NULL && fin->fin_fr->fr_type == FR_T_IPF) {
frdest_t *fdp = &fin->fin_fr->fr_rif;
if ((fdp->fd_ptr != NULL) &&
(fdp->fd_ptr != (struct ifnet *)-1))
return ipf_fastroute(m, mpp, &fnew, fdp);
}
return ipf_fastroute(m, mpp, &fnew, NULL);
}
int
ipf_send_icmp_err(type, fin, dst)
int type;
fr_info_t *fin;
int dst;
{
int err, hlen = 0, xtra = 0, iclen, ohlen = 0, avail;
struct in_addr dst4;
struct icmp *icmp;
struct mbuf *m;
i6addr_t dst6;
void *ifp;
#ifdef USE_INET6
ip6_t *ip6, *ip62;
int code;
#endif
ip_t *ip, *ip2;
if ((type < 0) || (type > ICMP_MAXTYPE))
return -1;
#ifdef USE_INET6
code = fin->fin_icode;
if ((code < 0) || (code > sizeof(icmptoicmp6unreach)/sizeof(int)))
return -1;
#endif
if (ipf_checkl4sum(fin) == -1)
return -1;
avail = 0;
ifp = fin->fin_ifp;
if (fin->fin_v == 4) {
if ((fin->fin_p == IPPROTO_ICMP) && !(fin->fin_flx & FI_SHORT))
switch (ntohs(fin->fin_data[0]) >> 8)
{
case ICMP_ECHO :
case ICMP_TSTAMP :
case ICMP_IREQ :
case ICMP_MASKREQ :
break;
default :
return 0;
}
avail = MLEN;
m = m_get(M_DONTWAIT, MT_HEADER);
if (m == NULL)
return -1;
if (dst == 0) {
if (ipf_ifpaddr(softc, 4, FRI_NORMAL, ifp,
&dst6, NULL) == -1) {
FREE_MB_T(m);
return -1;
}
dst4 = dst6.in4;
} else
dst4.s_addr = fin->fin_daddr;
hlen = sizeof(ip_t);
if (fin->fin_hlen < fin->fin_plen)
xtra = MIN(fin->fin_dlen, 8);
else
xtra = 0;
}
#ifdef USE_INET6
else if (fin->fin_v == 6) {
hlen = sizeof(ip6_t);
ohlen = sizeof(ip6_t);
type = icmptoicmp6types[type];
if (type == ICMP6_DST_UNREACH)
code = icmptoicmp6unreach[code];
MGETHDR(m, M_DONTWAIT, MT_HEADER);
if (m == NULL)
return -1;
MCLGET(m, M_DONTWAIT);
if (m == NULL)
return -1;
avail = (m->m_flags & M_EXT) ? MCLBYTES : MHLEN;
xtra = MIN(fin->fin_plen,
avail - hlen - sizeof(*icmp) - max_linkhdr);
if (dst == 0) {
if (ipf_ifpaddr(softc, 6, FRI_NORMAL, ifp,
&dst6, NULL) == -1) {
FREE_MB_T(m);
return -1;
}
} else
dst6 = fin->fin_dst6;
}
#endif
else {
FREE_MB_T(m);
return -1;
}
iclen = hlen + sizeof(*icmp);
# if (BSD >= 199103)
avail -= (max_linkhdr + iclen);
if (avail < 0) {
FREE_MB_T(m);
return -1;
}
m->m_data += max_linkhdr;
m->m_pkthdr.rcvif = (struct ifnet *)0;
iclen += xtra;
m->m_pkthdr.len = iclen;
#else
avail -= (m->m_off + iclen);
if (avail < 0) {
FREE_MB_T(m);
return -1;
}
iclen += xtra;
#endif
m->m_len = iclen;
ip = mtod(m, ip_t *);
icmp = (struct icmp *)((char *)ip + hlen);
ip2 = (ip_t *)&icmp->icmp_ip;
icmp->icmp_type = type;
icmp->icmp_code = fin->fin_icode;
icmp->icmp_cksum = 0;
#ifdef icmp_nextmtu
if (type == ICMP_UNREACH && fin->fin_icode == ICMP_UNREACH_NEEDFRAG) {
if (fin->fin_mtu != 0) {
icmp->icmp_nextmtu = htons(fin->fin_mtu);
} else if (ifp != NULL) {
icmp->icmp_nextmtu = htons(GETIFMTU_4(ifp));
} else { /* make up a number... */
icmp->icmp_nextmtu = htons(fin->fin_plen - 20);
}
}
#endif
bcopy((char *)fin->fin_ip, (char *)ip2, ohlen);
#ifdef USE_INET6
ip6 = (ip6_t *)ip;
if (fin->fin_v == 6) {
ip62 = (ip6_t *)ip2;
ip62->ip6_plen = htons(ip62->ip6_plen);
ip6->ip6_flow = ((ip6_t *)fin->fin_ip)->ip6_flow;
ip6->ip6_plen = htons(iclen - hlen);
ip6->ip6_nxt = IPPROTO_ICMPV6;
ip6->ip6_hlim = 0;
ip6->ip6_src = dst6;
ip6->ip6_dst = fin->fin_src6;
if (xtra > 0)
bcopy((char *)fin->fin_ip + fin->fin_hlen,
(char *)&icmp->icmp_ip + fin->fin_hlen, xtra);
icmp->icmp_cksum = in6_cksum(m, IPPROTO_ICMPV6,
sizeof(*ip6), iclen - hlen);
} else
#endif
{
ip->ip_p = IPPROTO_ICMP;
ip->ip_src.s_addr = dst4.s_addr;
ip->ip_dst.s_addr = fin->fin_saddr;
if (xtra > 0)
bcopy((char *)fin->fin_ip + fin->fin_hlen,
(char *)&icmp->icmp_ip + fin->fin_hlen, xtra);
icmp->icmp_cksum = ipf_cksum((u_short *)icmp,
sizeof(*icmp) + 8);
ip->ip_len = iclen;
ip->ip_p = IPPROTO_ICMP;
}
err = ipf_send_ip(fin, m, &m);
return err;
}
void
ipfinit(void)
{
int i;
for (i = 0; i < 256; i++)
if (cdevsw[i].d_open == ipfopen) {
printf("ipfinit:ipfilter @%d\n", i); break;
}
if (i == 256)
printf("ipfinit:ipfilter not found\n");
if (ipf_attach() != 0)
printf("IP Filter failed to attach\n");
else
ip_init();
}
int
ipfattach(void)
{
int i;
for (i = 0; i < 256; i++)
if (cdevsw[i].d_open == ipfopen) {
printf("ipfattach:ipfilter @%d\n", i); break;
}
if (i == 256)
printf("ipfattach:ipfilter not found\n");
return 0;
}
void
ipfstart(void)
{
int i;
for (i = 0; i < 256; i++)
if (cdevsw[i].d_open == ipfopen) {
printf("ipfstart:ipfilter @%d\n", i);
break;
}
if (i==256)
printf("ipfstart:ipfilter not found\n");
}
size_t
mbufchainlen(m0)
register struct mbuf *m0;
{
register size_t len = 0;
for (; m0; m0 = m0->m_next)
len += m0->m_len;
return len;
}
/*
* m0 - pointer to mbuf where the IP packet starts
* mpp - pointer to the mbuf pointer that is the start of the mbuf chain
*/
int
ipf_fastroute(m0, mpp, fin, fdp)
struct mbuf *m0, **mpp;
fr_info_t *fin;
frdest_t *fdp;
{
register struct ip *ip, *mhip;
register struct mbuf *m = *mpp;
register struct route *ro;
int len, off, error = 0, hlen, code;
struct ifnet *ifp, *sifp;
struct sockaddr_in *dst;
struct route iproute;
frentry_t *fr;
hlen = fin->fin_hlen;
ip = mtod(m0, struct ip *);
#ifdef USE_INET6
if (fin->fin_v == 6) {
/*
* currently "to <if>" and "to <if>:ip#" are not supported
* for IPv6
*/
return ip6_output(m0, NULL, NULL, 0, NULL, NULL);
}
#endif
/*
* Route packet.
*/
ROUTE_RDLOCK();
ro = &iproute;
bzero((caddr_t)ro, sizeof (*ro));
dst = (struct sockaddr_in *)&ro->ro_dst;
dst->sin_family = AF_INET;
dst->sin_addr = ip->ip_dst;
fr = fin->fin_fr;
if (fdp != NULL)
ifp = fdp->fd_ptr;
else
ifp = fin->fin_ifp;
if ((fdp != NULL) && (fdp->fd_ip.s_addr != 0))
dst->sin_addr = fdp->fd_ip.s_addr;
rtalloc(ro);
ROUTE_UNLOCK();
if (!ifp) {
if (!fr || !(fr->fr_flags & FR_FASTROUTE)) {
error = -2;
goto bad;
}
if (ro->ro_rt == 0 || (ifp = ro->ro_rt->rt_ifp) == 0) {
if (in_localaddr(ip->ip_dst))
error = EHOSTUNREACH;
else
error = ENETUNREACH;
goto bad;
}
if (ro->ro_rt->rt_flags & RTF_GATEWAY)
dst = (struct sockaddr_in *)&ro->ro_rt->rt_gateway;
}
if (ro->ro_rt)
ro->ro_rt->rt_use++;
/*
* For input packets which are being "fastrouted", they won't
* go back through output filtering and miss their chance to get
* NAT'd and counted. Duplicated packets aren't considered to be
* part of the normal packet stream, so do not NAT them or pass
* them through stateful checking, etc.
*/
if ((fdp != &fr->fr_dif) && (fin->fin_out == 0)) {
sifp = fin->fin_ifp;
fin->fin_ifp = ifp;
fin->fin_out = 1;
(void) ipf_acctpkt(fin, NULL);
fin->fin_fr = NULL;
if (!fr || !(fr->fr_flags & FR_RETMASK)) {
u_32_t pass;
(void) ipf_state_check(fin, &pass);
}
switch (ipf_nat_checkout(fin, NULL))
{
case 0 :
break;
case 1 :
ip->ip_sum = 0;
break;
case -1 :
error = -1;
goto bad;
break;
}
fin->fin_ifp = sifp;
fin->fin_out = 0;
} else
ip->ip_sum = 0;
/*
* If small enough for interface, can just send directly.
*/
if (ntohs(ip->ip_len) <= ifp->if_mtu) {
if (!ip->ip_sum)
ip->ip_sum = in_cksum(m, hlen);
#if IRIX >= 60500
error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst,
NULL);
#else
error = (*ifp->if_output)(ifp, m, (struct sockaddr *)dst);
#endif
goto done;
}
/*
* Too large for interface; fragment if possible.
* Must be able to put at least 8 bytes per fragment.
*/
if (ip->ip_off & htons(IP_DF)) {
error = EMSGSIZE;
goto bad;
}
len = (ifp->if_mtu - hlen) &~ 7;
if (len < 8) {
error = EMSGSIZE;
goto bad;
}
{
int mhlen, firstlen = len;
struct mbuf **mnext = &m->m_act;
/*
* Loop through length of segment after first fragment,
* make new header and copy data of each part and link onto chain.
*/
m0 = m;
mhlen = sizeof (struct ip);
for (off = hlen + len; off < ntohs(ip->ip_len); off += len) {
u_short ipoff, iplen;
#ifdef MGETHDR
MGETHDR(m, M_DONTWAIT, MT_HEADER);
#else
MGET(m, M_DONTWAIT, MT_HEADER);
#endif
if (m == 0) {
error = ENOBUFS;
goto bad;
}
#if (BSD >= 199103)
m->m_data += max_linkhdr;
#else
m->m_off = MMAXOFF - hlen;
#endif
mhip = mtod(m, struct ip *);
bcopy((char *)ip, (char *)mhip, sizeof(*ip));
if (hlen > sizeof (struct ip)) {
mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
IP_HL_A(mhip, mhlen >> 2);
}
m->m_len = mhlen;
ipoff = ntohs(ip->ip_off);
iplen = ntohs(ip->ip_len);
mhip->ip_off = ((off - hlen) >> 3) + (ipoff & ~IP_MF);
if (ipoff & IP_MF)
mhip->ip_off |= IP_MF;
if (off + len >= iplen)
len = iplen - off;
else
mhip->ip_off |= IP_MF;
mhip->ip_len = htons((u_short)(len + mhlen));
m->m_next = m_copy(m0, off, len);
if (m->m_next == 0) {
error = ENOBUFS; /* ??? */
goto sendorfree;
}
#if (BSD >= 199103)
m->m_pkthdr.len = mhlen + len;
m->m_pkthdr.rcvif = NULL;
#endif
mhip->ip_off = htons((u_short)mhip->ip_off);
mhip->ip_sum = 0;
mhip->ip_sum = in_cksum(m, mhlen);
*mnext = m;
mnext = &m->m_act;
}
/*
* Update first fragment by trimming what's been copied out
* and updating header, then send each fragment (in order).
*/
m_adj(m0, hlen + firstlen - ntohs(ip->ip_len));
ip->ip_len = htons((u_short)(hlen + firstlen));
ip->ip_off = htons(IP_MF);
ip->ip_sum = 0;
ip->ip_sum = in_cksum(m0, hlen);
sendorfree:
for (m = m0; m; m = m0) {
m0 = m->m_act;
m->m_act = 0;
if (error == 0)
#if IRIX >= 60500
error = (*ifp->if_output)(ifp, m,
(struct sockaddr *)dst, ro->ro_rt);
#else
error = (*ifp->if_output)(ifp, m,
(struct sockaddr *)dst);
#endif
else
m_freem(m);
}
}
done:
if (!error)
ipf_frouteok[0]++;
else
ipf_frouteok[1]++;
if (ro->ro_rt)
RTFREE(ro->ro_rt);
*mpp = NULL;
return 0;
bad:
if (error == EMSGSIZE) {
sifp = fin->fin_ifp;
code = fin->fin_icode;
fin->fin_icode = ICMP_UNREACH_NEEDFRAG;
fin->fin_ifp = ifp;
(void) ipf_send_icmp_err(ICMP_UNREACH, fin, 1);
fin->fin_ifp = sifp;
fin->fin_icode = code;
}
m_freem(m);
goto done;
}
int
ipf_verifysrc(fin)
fr_info_t *fin;
{
struct sockaddr_in *dst;
struct route iproute;
bzero((char *)&iproute, sizeof(iproute));
dst = (struct sockaddr_in *)&iproute.ro_dst;
dst->sin_family = AF_INET;
dst->sin_addr.s_addr = fin->fin_saddr;
rtalloc(&iproute);
if (iproute.ro_rt == NULL)
return 0;
return (fin->fin_ifp == iproute.ro_rt->rt_ifp);
}
/*
* return the first IP Address associated with an interface
*/
int
ipf_ifpaddr(softc, v, atype, ifptr, inp, inpmask)
ipf_main_softc_t *softc;
int v, atype;
void *ifptr;
i6addr_t *inp, *inpmask;
{
#ifdef USE_INET6
struct in6_addr *inp6 = NULL;
#endif
struct sockaddr_in *sin, *mask;
struct ifaddr *ifa;
struct in_addr in;
struct ifnet *ifp;
if ((ifptr == NULL) || (ifptr == (void *)-1))
return -1;
mask = NULL;
ifp = ifptr;
if (v == 4)
inp->s_addr = 0;
#ifdef USE_INET6
else if (v == 6)
bzero((char *)inp, sizeof(*inp));
#endif
#if defined(IFF_DRVRLOCK) /* IRIX 6 */
ifa = &((struct in_ifaddr *)ifp->in_ifaddr)->ia_ifa;
#else
ifa = ifp->if_addrlist;
#endif
sin = (struct sockaddr_in *)ifa->ifa_addr;
while (sin && ifa) {
if ((v == 4) && (sin->sin_family == AF_INET))
break;
# ifdef USE_INET6
if ((v == 6) && (sin->sin_family == AF_INET6)) {
inp6 = &((struct sockaddr_in6 *)sin)->sin6_addr;
if (!IN6_IS_ADDR_LINKLOCAL(inp6) &&
!IN6_IS_ADDR_LOOPBACK(inp6))
break;
}
# endif
ifa = ifa->ifa_next;
if (ifa != NULL)
sin = (struct sockaddr_in *)ifa->ifa_addr;
}
if (ifa == NULL || sin == NULL)
return -1;
mask = (struct sockaddr_in *)ifa->ifa_netmask;
if (atype == FRI_BROADCAST)
sin = (struct sockaddr_in *)ifa->ifa_broadaddr;
else if (atype == FRI_PEERADDR)
sin = (struct sockaddr_in *)ifa->ifa_dstaddr;
#ifdef USE_INET6
if (v == 6)
return ipf_ifpfillv6addr(atype, (struct sockaddr_in6 *)sin,
(struct sockaddr_in6 *)mask,
inp, inpmask);
#endif
return ipf_ifpfillv4addr(atype, sin, mask, &inp->in4, &inpmask->in4);
}
void
#if IRIX >= 60500
ipf_slowtimer(void *arg)
#else
ipf_slowtimer()
#endif
{
if (ipf_running <= 0) {
#if IRIX >= 60500
ipf_timer_id = 0;
#endif
return;
}
READ_ENTER(&ipf_global);
if (ipf_running <= 0) {
#if IRIX >= 60500
ipf_timer_id = 0;
#endif
RWLOCK_EXIT(&ipf_global);
return;
}
ipf_ipfilter_intfsync();
ipf_expiretokens(&ipfmain);
ipf_frag_expire(&ipfmain);
ipf_state_expire(&ipfmain);
ipf_nat_expire(&ipfmain);
ipf_auth_expire(&ipfmain);
ipf_lookup_expire(&ipfmain);
ipf_rule_expire(&ipfmain);
ipf_ticks++;
#if IRIX >= 60500
ipf_timer_id = timeout(ipf_slowtimer, NULL, hz/2);
#else
timeout(ipf_slowtimer, NULL, hz/2);
#endif
RWLOCK_EXIT(&ipf_global);
}
u_32_t
ipf_newisn(fin)
fr_info_t *fin;
{
static iss_seq_off = 0;
u_char hash[16];
u_32_t newiss;
MD5_CTX ctx;
/*
* Compute the base value of the ISS. It is a hash
* of (saddr, sport, daddr, dport, secret).
*/
MD5Init(&ctx);
MD5Update(&ctx, (u_char *) &fin->fin_fi.fi_src,
sizeof(fin->fin_fi.fi_src));
MD5Update(&ctx, (u_char *) &fin->fin_fi.fi_dst,
sizeof(fin->fin_fi.fi_dst));
MD5Update(&ctx, (u_char *) &fin->fin_dat, sizeof(fin->fin_dat));
MD5Update(&ctx, ipf_iss_secret, sizeof(ipf_iss_secret));
MD5Final(hash, &ctx);
bcopy(hash, &newiss, sizeof(newiss));
/*
* Now increment our "timer", and add it in to
* the computed value.
*
* XXX Use `addin'?
* XXX TCP_ISSINCR too large to use?
*/
iss_seq_off += 0x00010000;
newiss += iss_seq_off;
return newiss;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_nextipid */
/* Returns: int - 0 == success, -1 == error (packet should be droppped) */
/* Parameters: fin(I) - pointer to packet information */
/* */
/* Returns the next IPv4 ID to use for this packet. */
/* ------------------------------------------------------------------------ */
u_short
ipf_nextipid(fin)
fr_info_t *fin;
{
static u_short ipid = 0;
u_short id;
MUTEX_ENTER(&ipf_rw);
id = ipid++;
MUTEX_EXIT(&ipf_rw);
return id;
}
void
ipf_checkv4sum(fin)
fr_info_t *fin;
{
#ifdef IPFILTER_CKSUM
if (ipf_checkl4sum(fin) == -1)
fin->fin_flx |= FI_BAD;
#endif
}
#ifdef USE_INET6
INLINE void
ipf_checkv6sum(fin)
fr_info_t *fin;
{
#ifdef IPFILTER_CKSUM
if (ipf_checkl4sum(fin) == -1)
fin->fin_flx |= FI_BAD;
#endif
}
#endif /* USE_INET6 */
/* ------------------------------------------------------------------------ */
/* Function: ipf_pullup */
/* Returns: NULL == pullup failed, else pointer to protocol header */
/* Parameters: xmin(I)- pointer to buffer where data packet starts */
/* fin(I) - pointer to packet information */
/* len(I) - number of bytes to pullup */
/* */
/* Attempt to move at least len bytes (from the start of the buffer) into a */
/* single buffer for ease of access. Operating system native functions are */
/* used to manage buffers - if necessary. If the entire packet ends up in */
/* a single buffer, set the FI_COALESCE flag even though ipf_coalesce() has */
/* not been called. Both fin_ip and fin_dp are updated before exiting _IF_ */
/* and ONLY if the pullup succeeds. */
/* */
/* We assume that 'min' is a pointer to a buffer that is part of the chain */
/* of buffers that starts at *fin->fin_mp. */
/* ------------------------------------------------------------------------ */
void *
ipf_pullup(xmin, fin, len)
mb_t *xmin;
fr_info_t *fin;
int len;
{
int out = fin->fin_out, dpoff;
mb_t *m = xmin, *n;
char *ip;
if (m == NULL)
return NULL;
ip = (char *)fin->fin_ip;
if ((fin->fin_flx & FI_COALESCE) != 0)
return ip;
if (fin->fin_dp != NULL)
dpoff = (char *)fin->fin_dp - (char *)ip;
else
dpoff = 0;
if (M_LEN(m) < len) {
KMALLOCS(fin->fin_hbuf, void *, fin->fin_plen);
if (fin->fin_hbuf == NULL) {
return NULL;
}
m_copydata(m, 0, fin->fin_plen, fin->fin_hbuf);
ip = fin->fin_hbuf;
fin->fin_flx |= FI_COALESCE;
} else if (len == fin->fin_plen) {
fin->fin_flx |= FI_COALESCE;
}
fin->fin_ip = (ip_t *)ip;
if (fin->fin_dp != NULL)
fin->fin_dp = (char *)fin->fin_ip + dpoff;
return ip;
}
int
ipf_inject(fin, m)
fr_info_t *fin;
mb_t *m;
{
int error;
if (fin->fin_out == 0) {
struct ifqueue *ifq;
#if (IRIX >= 60516)
ifq = &((struct ifnet *)fin->fin_ifp)->if_snd;
#else
ifq = &ipintrq;
#endif
if (IF_QFULL(ifq)) {
IF_DROP(ifq);
FREE_MB_T(m);
error = ENOBUFS;
} else {
IF_ENQUEUE(ifq, m);
#if IRIX < 60500
schednetisr(NETISR_IP);
#endif
error = 0;
}
} else {
#if IRIX >= 60500
error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL, NULL);
#else
error = ip_output(m, NULL, NULL, IP_FORWARDING, NULL);
#endif
}
return error;
}
/*
* In the face of no kernel random function, this is implemented...it is
* not meant to be random, just a fill in.
*/
int
ipf_random()
{
static int last = 0;
static int calls = 0;
struct timeval tv;
int number;
GETKTIME(&tv);
last *= tv.tv_usec + calls++;
last += (int)&range * ipf_ticks;
number = last + tv.tv_sec;
return number;
}