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src.rivoreo.one / net / ipfilter / b63f04c0e01ab77e9ec1ccadc787e2136d5d5ee5 / . / ip_proxy.c
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/*
* Copyright (C) 2012 by Darren Reed.
*
* See the IPFILTER.LICENCE file for details on licencing.
*/
#if defined(KERNEL) || defined(_KERNEL)
# undef KERNEL
# undef _KERNEL
# define KERNEL 1
# define _KERNEL 1
#endif
#include <sys/errno.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/file.h>
#if !defined(AIX)
# include <sys/fcntl.h>
#endif
#if !defined(_KERNEL) && !defined(__KERNEL__)
# include <stdio.h>
# include <string.h>
# include <stdlib.h>
# include <ctype.h>
# define _KERNEL
# ifdef __OpenBSD__
struct file;
# endif
# include <sys/uio.h>
# undef _KERNEL
#endif
#if !defined(linux)
# include <sys/protosw.h>
#endif
#include <sys/socket.h>
#if defined(_KERNEL)
# if !defined(__NetBSD__) && !defined(sun) && !defined(__osf__) && \
!defined(__OpenBSD__) && !defined(__hpux) && !defined(__sgi) && \
!defined(AIX)
# include <sys/ctype.h>
# endif
# include <sys/systm.h>
# if !defined(__SVR4) && !defined(__svr4__)
# include <sys/mbuf.h>
# endif
#endif
#if defined(_KERNEL) && (__FreeBSD_version >= 220000)
# include <sys/filio.h>
# include <sys/fcntl.h>
#else
# include <sys/ioctl.h>
#endif
#if defined(__SVR4) || defined(__svr4__)
# include <sys/byteorder.h>
# ifdef _KERNEL
# include <sys/dditypes.h>
# endif
# include <sys/stream.h>
# include <sys/kmem.h>
#endif
#if __FreeBSD__ > 2
# include <sys/queue.h>
#endif
#include <net/if.h>
#ifdef sun
# include <net/af.h>
#endif
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#ifndef linux
# include <netinet/ip_var.h>
#endif
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include "netinet/ip_compat.h"
#include <netinet/tcpip.h>
#include "netinet/ip_fil.h"
#include "netinet/ip_nat.h"
#include "netinet/ip_state.h"
#include "netinet/ip_proxy.h"
#if (__FreeBSD_version >= 300000)
# include <sys/malloc.h>
#endif
/* END OF INCLUDES */
#include "netinet/ip_ftp_pxy.c"
#include "netinet/ip_tftp_pxy.c"
#include "netinet/ip_rcmd_pxy.c"
#include "netinet/ip_pptp_pxy.c"
#if defined(_KERNEL)
# include "netinet/ip_irc_pxy.c"
# include "netinet/ip_raudio_pxy.c"
# include "netinet/ip_netbios_pxy.c"
#endif
#include "netinet/ip_ipsec_pxy.c"
#include "netinet/ip_rpcb_pxy.c"
#if !defined(lint)
static const char rcsid[] = "@(#)$Id$";
#endif
#define AP_SESS_SIZE 53
static int ipf_proxy_fixseqack __P((fr_info_t *, ip_t *, ap_session_t *, int ));
static aproxy_t *ipf_proxy_create_clone __P((ipf_main_softc_t *, aproxy_t *));
typedef struct ipf_proxy_softc_s {
int ips_proxy_debug;
int ips_proxy_session_size;
ap_session_t **ips_sess_tab;
ap_session_t *ips_sess_list;
aproxy_t *ips_proxies;
int ips_init_run;
ipftuneable_t *ipf_proxy_tune;
} ipf_proxy_softc_t;
static ipftuneable_t ipf_proxy_tuneables[] = {
{ { (void *)offsetof(ipf_proxy_softc_t, ips_proxy_debug) },
"proxy_debug", 0, 0x1f,
stsizeof(ipf_proxy_softc_t, ips_proxy_debug),
0, NULL, NULL },
{ { NULL }, NULL, 0, 0,
0,
0, NULL, NULL}
};
static aproxy_t *ap_proxylist = NULL;
static aproxy_t ips_proxies[] = {
#ifdef IPF_FTP_PROXY
{ NULL, NULL, "ftp", (char)IPPROTO_TCP, 0, 0, 0,
ipf_p_ftp_main_load, ipf_p_ftp_main_unload,
ipf_p_ftp_soft_create, ipf_p_ftp_soft_destroy,
NULL, NULL,
ipf_p_ftp_new, ipf_p_ftp_del, ipf_p_ftp_in, ipf_p_ftp_out, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_TFTP_PROXY
{ NULL, NULL, "tftp", (char)IPPROTO_UDP, 0, 0, 0,
ipf_p_tftp_main_load, ipf_p_tftp_main_unload,
ipf_p_tftp_soft_create, ipf_p_tftp_soft_destroy,
NULL, NULL,
ipf_p_tftp_new, ipf_p_tftp_del,
ipf_p_tftp_in, ipf_p_tftp_out, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_IRC_PROXY
{ NULL, NULL, "irc", (char)IPPROTO_TCP, 0, 0, 0,
ipf_p_irc_main_load, ipf_p_irc_main_unload,
NULL, NULL,
NULL, NULL,
ipf_p_irc_new, NULL, NULL, ipf_p_irc_out, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_RCMD_PROXY
{ NULL, NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, 0,
ipf_p_rcmd_main_load, ipf_p_rcmd_main_unload,
NULL, NULL,
NULL, NULL,
ipf_p_rcmd_new, ipf_p_rcmd_del,
ipf_p_rcmd_in, ipf_p_rcmd_out, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_RAUDIO_PROXY
{ NULL, NULL, "raudio", (char)IPPROTO_TCP, 0, 0, 0,
ipf_p_raudio_main_load, ipf_p_raudio_main_unload,
NULL, NULL,
NULL, NULL,
ipf_p_raudio_new, NULL, ipf_p_raudio_in, ipf_p_raudio_out, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_MSNRPC_PROXY
{ NULL, NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, 0,
ipf_p_msnrpc_init, ipf_p_msnrpc_fini,
NULL, NULL,
NULL, NULL,
ipf_p_msnrpc_new, NULL, ipf_p_msnrpc_in, ipf_p_msnrpc_out, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_NETBIOS_PROXY
{ NULL, NULL, "netbios", (char)IPPROTO_UDP, 0, 0, 0,
ipf_p_netbios_main_load, ipf_p_netbios_main_unload,
NULL, NULL,
NULL, NULL,
NULL, NULL, NULL, ipf_p_netbios_out, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_IPSEC_PROXY
{ NULL, NULL, "ipsec", (char)IPPROTO_UDP, 0, 0, 0,
NULL, NULL,
ipf_p_ipsec_soft_create, ipf_p_ipsec_soft_destroy,
ipf_p_ipsec_soft_init, ipf_p_ipsec_soft_fini,
ipf_p_ipsec_new, ipf_p_ipsec_del,
ipf_p_ipsec_inout, ipf_p_ipsec_inout, ipf_p_ipsec_match,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_DNS_PROXY
{ NULL, NULL, "dns", (char)IPPROTO_UDP, 0, 0, 0,
NULL, NULL,
ipf_p_dns_soft_create, ipf_p_dns_soft_destroy,
NULL, NULL,
ipf_p_dns_new, ipf_p_ipsec_del,
ipf_p_dns_inout, ipf_p_dns_inout, ipf_p_dns_match,
ipf_p_dns_ctl, NULL, NULL, NULL },
#endif
#ifdef IPF_PPTP_PROXY
{ NULL, NULL, "pptp", (char)IPPROTO_TCP, 0, 0, 0,
ipf_p_pptp_main_load, ipf_p_pptp_main_unload,
NULL, NULL,
NULL, NULL,
ipf_p_pptp_new, ipf_p_pptp_del,
ipf_p_pptp_inout, ipf_p_pptp_inout, NULL,
NULL, NULL, NULL, NULL },
#endif
#ifdef IPF_RPCB_PROXY
# ifndef _KERNEL
{ NULL, NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0, 0,
NULL, NULL,
NULL, NULL,
NULL, NULL,
ipf_p_rpcb_new, ipf_p_rpcb_del,
ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
NULL, NULL, NULL, NULL },
# endif
{ NULL, NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0, 0,
ipf_p_rpcb_main_load, ipf_p_rpcb_main_unload,
NULL, NULL,
NULL, NULL,
ipf_p_rpcb_new, ipf_p_rpcb_del,
ipf_p_rpcb_in, ipf_p_rpcb_out, NULL,
NULL, NULL, NULL, NULL },
#endif
{ NULL, NULL, "", '\0', 0, 0, 0,
NULL, NULL,
NULL, NULL,
NULL, NULL,
NULL, NULL,
NULL, NULL, NULL,
NULL, NULL, NULL, NULL }
};
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_main_load */
/* Returns: int - 0 == success, else failure. */
/* Parameters: Nil */
/* */
/* Initialise hook for kernel application proxies. */
/* Call the initialise routine for all the compiled in kernel proxies. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_main_load()
{
aproxy_t *ap;
for (ap = ips_proxies; ap->apr_p; ap++) {
if (ap->apr_load != NULL)
(*ap->apr_load)();
}
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_main_unload */
/* Returns: int - 0 == success, else failure. */
/* Parameters: Nil */
/* */
/* Unload hook for kernel application proxies. */
/* Call the finialise routine for all the compiled in kernel proxies. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_main_unload()
{
aproxy_t *ap;
for (ap = ips_proxies; ap->apr_p; ap++)
if (ap->apr_unload != NULL)
(*ap->apr_unload)();
for (ap = ap_proxylist; ap; ap = ap->apr_next)
if (ap->apr_unload != NULL)
(*ap->apr_unload)();
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_soft_create */
/* Returns: void * - */
/* Parameters: softc(I) - pointer to soft context main structure */
/* */
/* Build the structure to hold all of the run time data to support proxies. */
/* ------------------------------------------------------------------------ */
void *
ipf_proxy_soft_create(softc)
ipf_main_softc_t *softc;
{
ipf_proxy_softc_t *softp;
aproxy_t *last;
aproxy_t *apn;
aproxy_t *ap;
KMALLOC(softp, ipf_proxy_softc_t *);
if (softp == NULL)
return softp;
bzero((char *)softp, sizeof(*softp));
#if defined(_KERNEL)
softp->ips_proxy_debug = 0;
#else
softp->ips_proxy_debug = 2;
#endif
softp->ips_proxy_session_size = AP_SESS_SIZE;
softp->ipf_proxy_tune = ipf_tune_array_copy(softp,
sizeof(ipf_proxy_tuneables),
ipf_proxy_tuneables);
if (softp->ipf_proxy_tune == NULL) {
ipf_proxy_soft_destroy(softc, softp);
return NULL;
}
if (ipf_tune_array_link(softc, softp->ipf_proxy_tune) == -1) {
ipf_proxy_soft_destroy(softc, softp);
return NULL;
}
last = NULL;
for (ap = ips_proxies; ap->apr_p; ap++) {
apn = ipf_proxy_create_clone(softc, ap);
if (apn == NULL)
goto failed;
if (last != NULL)
last->apr_next = apn;
else
softp->ips_proxies = apn;
last = apn;
}
for (ap = ips_proxies; ap != NULL; ap = ap->apr_next) {
apn = ipf_proxy_create_clone(softc, ap);
if (apn == NULL)
goto failed;
if (last != NULL)
last->apr_next = apn;
else
softp->ips_proxies = apn;
last = apn;
}
return softp;
failed:
ipf_proxy_soft_destroy(softc, softp);
return NULL;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_soft_create */
/* Returns: void * - */
/* Parameters: softc(I) - pointer to soft context main structure */
/* orig(I) - pointer to proxy definition to copy */
/* */
/* This function clones a proxy definition given by orig and returns a */
/* a pointer to that copy. */
/* ------------------------------------------------------------------------ */
static aproxy_t *
ipf_proxy_create_clone(softc, orig)
ipf_main_softc_t *softc;
aproxy_t *orig;
{
aproxy_t *apn;
KMALLOC(apn, aproxy_t *);
if (apn == NULL)
return NULL;
bcopy((char *)orig, (char *)apn, sizeof(*apn));
apn->apr_next = NULL;
apn->apr_soft = NULL;
if (apn->apr_create != NULL) {
apn->apr_soft = (*apn->apr_create)(softc);
if (apn->apr_soft == NULL) {
KFREE(apn);
return NULL;
}
}
apn->apr_parent = orig;
orig->apr_clones++;
return apn;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_soft_create */
/* Returns: int - 0 == success, else failure. */
/* Parameters: softc(I) - pointer to soft context main structure */
/* arg(I) - pointer to proxy contect data */
/* */
/* Initialise the proxy context and walk through each of the proxies and */
/* call its initialisation function. This allows for proxies to do any */
/* local setup prior to actual use. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_soft_init(softc, arg)
ipf_main_softc_t *softc;
void *arg;
{
ipf_proxy_softc_t *softp;
aproxy_t *ap;
u_int size;
int err;
softp = arg;
size = softp->ips_proxy_session_size * sizeof(ap_session_t *);
KMALLOCS(softp->ips_sess_tab, ap_session_t **, size);
if (softp->ips_sess_tab == NULL)
return -1;
bzero(softp->ips_sess_tab, size);
for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
if (ap->apr_init != NULL) {
err = (*ap->apr_init)(softc, ap->apr_soft);
if (err != 0)
return -2;
}
}
softp->ips_init_run = 1;
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_soft_create */
/* Returns: int - 0 == success, else failure. */
/* Parameters: softc(I) - pointer to soft context main structure */
/* arg(I) - pointer to proxy contect data */
/* */
/* This function should always succeed. It is responsible for ensuring that */
/* the proxy context can be safely called when ipf_proxy_soft_destroy is */
/* called and suring all of the proxies have similarly been instructed. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_soft_fini(softc, arg)
ipf_main_softc_t *softc;
void *arg;
{
ipf_proxy_softc_t *softp = arg;
aproxy_t *ap;
for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next) {
if (ap->apr_fini != NULL) {
(*ap->apr_fini)(softc, ap->apr_soft);
}
}
if (softp->ips_sess_tab != NULL) {
KFREES(softp->ips_sess_tab,
softp->ips_proxy_session_size * sizeof(ap_session_t *));
softp->ips_sess_tab = NULL;
}
softp->ips_init_run = 0;
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_soft_destroy */
/* Returns: Nil */
/* Parameters: softc(I) - pointer to soft context main structure */
/* arg(I) - pointer to proxy contect data */
/* */
/* Free up all of the local data structures allocated during creation. */
/* ------------------------------------------------------------------------ */
void
ipf_proxy_soft_destroy(softc, arg)
ipf_main_softc_t *softc;
void *arg;
{
ipf_proxy_softc_t *softp = arg;
aproxy_t *ap;
while ((ap = softp->ips_proxies) != NULL) {
softp->ips_proxies = ap->apr_next;
if (ap->apr_destroy != NULL)
(*ap->apr_destroy)(softc, ap->apr_soft);
ap->apr_parent->apr_clones--;
KFREE(ap);
}
if (softp->ipf_proxy_tune != NULL) {
ipf_tune_array_unlink(softc, softp->ipf_proxy_tune);
KFREES(softp->ipf_proxy_tune, sizeof(ipf_proxy_tuneables));
softp->ipf_proxy_tune = NULL;
}
KFREE(softp);
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_flush */
/* Returns: Nil */
/* Parameters: arg(I) - pointer to proxy contect data */
/* how(I) - indicates the type of flush operation */
/* */
/* Walk through all of the proxies and pass on the flush command as either */
/* a flush or a clear. */
/* ------------------------------------------------------------------------ */
void
ipf_proxy_flush(arg, how)
void *arg;
int how;
{
ipf_proxy_softc_t *softp = arg;
aproxy_t *ap;
switch (how)
{
case 0 :
for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
if (ap->apr_flush != NULL)
(*ap->apr_flush)(ap, how);
break;
case 1 :
for (ap = softp->ips_proxies; ap; ap = ap->apr_next)
if (ap->apr_clear != NULL)
(*ap->apr_clear)(ap);
break;
default :
break;
}
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_add */
/* Returns: int - 0 == success, else failure. */
/* Parameters: ap(I) - pointer to proxy structure */
/* */
/* Dynamically add a new kernel proxy. Ensure that it is unique in the */
/* collection compiled in and dynamically added. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_add(arg, ap)
void *arg;
aproxy_t *ap;
{
ipf_proxy_softc_t *softp = arg;
aproxy_t *a;
for (a = ips_proxies; a->apr_p; a++)
if ((a->apr_p == ap->apr_p) &&
!strncmp(a->apr_label, ap->apr_label,
sizeof(ap->apr_label))) {
if (softp->ips_proxy_debug & 0x01)
printf("ipf_proxy_add: %s/%d present (B)\n",
a->apr_label, a->apr_p);
return -1;
}
for (a = ap_proxylist; (a != NULL); a = a->apr_next)
if ((a->apr_p == ap->apr_p) &&
!strncmp(a->apr_label, ap->apr_label,
sizeof(ap->apr_label))) {
if (softp->ips_proxy_debug & 0x01)
printf("ipf_proxy_add: %s/%d present (D)\n",
a->apr_label, a->apr_p);
return -1;
}
ap->apr_next = ap_proxylist;
ap_proxylist = ap;
if (ap->apr_load != NULL)
(*ap->apr_load)();
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_ctl */
/* Returns: int - 0 == success, else error */
/* Parameters: softc(I) - pointer to soft context main structure */
/* arg(I) - pointer to proxy context */
/* ctl(I) - pointer to proxy control structure */
/* */
/* Check to see if the proxy this control request has come through for */
/* exists, and if it does and it has a control function then invoke that */
/* control function. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_ctl(softc, arg, ctl)
ipf_main_softc_t *softc;
void *arg;
ap_ctl_t *ctl;
{
ipf_proxy_softc_t *softp = arg;
aproxy_t *a;
int error;
a = ipf_proxy_lookup(arg, ctl->apc_p, ctl->apc_label);
if (a == NULL) {
if (softp->ips_proxy_debug & 0x01)
printf("ipf_proxy_ctl: can't find %s/%d\n",
ctl->apc_label, ctl->apc_p);
IPFERROR(80001);
error = ESRCH;
} else if (a->apr_ctl == NULL) {
if (softp->ips_proxy_debug & 0x01)
printf("ipf_proxy_ctl: no ctl function for %s/%d\n",
ctl->apc_label, ctl->apc_p);
IPFERROR(80002);
error = ENXIO;
} else {
error = (*a->apr_ctl)(softc, a->apr_soft, ctl);
if ((error != 0) && (softp->ips_proxy_debug & 0x02))
printf("ipf_proxy_ctl: %s/%d ctl error %d\n",
a->apr_label, a->apr_p, error);
}
return error;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_del */
/* Returns: int - 0 == success, else failure. */
/* Parameters: ap(I) - pointer to proxy structure */
/* */
/* Delete a proxy that has been added dynamically from those available. */
/* If it is in use, return 1 (do not destroy NOW), not in use 0 or -1 */
/* if it cannot be matched. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_del(ap)
aproxy_t *ap;
{
aproxy_t *a, **app;
for (app = &ap_proxylist; ((a = *app) != NULL); app = &a->apr_next) {
if (a == ap) {
a->apr_flags |= APR_DELETE;
if (ap->apr_ref == 0 && ap->apr_clones == 0) {
*app = a->apr_next;
return 0;
}
return 1;
}
}
return -1;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_ok */
/* Returns: int - 1 == good match else not. */
/* Parameters: fin(I) - pointer to packet information */
/* tcp(I) - pointer to TCP/UDP header */
/* nat(I) - pointer to current NAT session */
/* */
/* This function extends the NAT matching to ensure that a packet that has */
/* arrived matches the proxy information attached to the NAT rule. Notably, */
/* if the proxy is scheduled to be deleted then packets will not match the */
/* rule even if the rule is still active. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_ok(fin, tcp, np)
fr_info_t *fin;
tcphdr_t *tcp;
ipnat_t *np;
{
aproxy_t *apr = np->in_apr;
u_short dport = np->in_odport;
if ((apr == NULL) || (apr->apr_flags & APR_DELETE) ||
(fin->fin_p != apr->apr_p))
return 0;
if ((tcp == NULL) && dport)
return 0;
return 1;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_ioctl */
/* Returns: int - 0 == success, else error */
/* Parameters: softc(I) - pointer to soft context main structure */
/* data(I) - pointer to ioctl data */
/* cmd(I) - ioctl command */
/* mode(I) - mode bits for device */
/* ctx(I) - pointer to context information */
/* */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_ioctl(softc, data, cmd, mode, ctx)
ipf_main_softc_t *softc;
caddr_t data;
ioctlcmd_t cmd;
int mode;
void *ctx;
{
ap_ctl_t ctl;
caddr_t ptr;
int error;
mode = mode; /* LINT */
switch (cmd)
{
case SIOCPROXY :
error = ipf_inobj(softc, data, NULL, &ctl, IPFOBJ_PROXYCTL);
if (error != 0) {
return error;
}
ptr = NULL;
if (ctl.apc_dsize > 0) {
KMALLOCS(ptr, caddr_t, ctl.apc_dsize);
if (ptr == NULL) {
IPFERROR(80003);
error = ENOMEM;
} else {
error = copyinptr(softc, ctl.apc_data, ptr,
ctl.apc_dsize);
if (error == 0)
ctl.apc_data = ptr;
}
} else {
ctl.apc_data = NULL;
error = 0;
}
if (error == 0)
error = ipf_proxy_ctl(softc, softc->ipf_proxy_soft,
&ctl);
if ((error != 0) && (ptr != NULL)) {
KFREES(ptr, ctl.apc_dsize);
}
break;
default :
IPFERROR(80004);
error = EINVAL;
}
return error;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_match */
/* Returns: int - 0 == success, else error */
/* Parameters: fin(I) - pointer to packet information */
/* nat(I) - pointer to current NAT session */
/* */
/* If a proxy has a match function, call that to do extended packet */
/* matching. Whilst other parts of the NAT code are rather lenient when it */
/* comes to the quality of the packet that it will transform, the proxy */
/* matching is not because they need to work with data, not just headers. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_match(fin, nat)
fr_info_t *fin;
nat_t *nat;
{
ipf_main_softc_t *softc = fin->fin_main_soft;
ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
aproxy_t *apr;
ipnat_t *ipn;
int result;
ipn = nat->nat_ptr;
if (softp->ips_proxy_debug & 0x04)
printf("ipf_proxy_match(%lx,%lx) aps %lx ptr %lx\n",
(u_long)fin, (u_long)nat, (u_long)nat->nat_aps,
(u_long)ipn);
if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_match: flx 0x%x (BAD|SHORT)\n",
fin->fin_flx);
return -1;
}
apr = ipn->in_apr;
if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_match:apr %lx apr_flags 0x%x\n",
(u_long)apr, apr ? apr->apr_flags : 0);
return -1;
}
if (apr->apr_match != NULL) {
result = (*apr->apr_match)(fin, nat->nat_aps, nat);
if (result != 0) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_match: result %d\n", result);
return -1;
}
}
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_new */
/* Returns: int - 0 == success, else error */
/* Parameters: fin(I) - pointer to packet information */
/* nat(I) - pointer to current NAT session */
/* */
/* Allocate a new application proxy structure and fill it in with the */
/* relevant details. call the init function once complete, prior to */
/* returning. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_new(fin, nat)
fr_info_t *fin;
nat_t *nat;
{
ipf_main_softc_t *softc = fin->fin_main_soft;
ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
register ap_session_t *aps;
aproxy_t *apr;
if (softp->ips_proxy_debug & 0x04)
printf("ipf_proxy_new(%lx,%lx) \n", (u_long)fin, (u_long)nat);
if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_new: nat_ptr %lx nat_aps %lx\n",
(u_long)nat->nat_ptr, (u_long)nat->nat_aps);
return -1;
}
apr = nat->nat_ptr->in_apr;
if ((apr->apr_flags & APR_DELETE) ||
(fin->fin_p != apr->apr_p)) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_new: apr_flags 0x%x p %d/%d\n",
apr->apr_flags, fin->fin_p, apr->apr_p);
return -1;
}
KMALLOC(aps, ap_session_t *);
if (!aps) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_new: malloc failed (%lu)\n",
(u_long)sizeof(ap_session_t));
return -1;
}
bzero((char *)aps, sizeof(*aps));
aps->aps_data = NULL;
aps->aps_apr = apr;
aps->aps_psiz = 0;
if (apr->apr_new != NULL)
if ((*apr->apr_new)(apr->apr_soft, fin, aps, nat) == -1) {
if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) {
KFREES(aps->aps_data, aps->aps_psiz);
}
KFREE(aps);
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_new: new(%lx) failed\n",
(u_long)apr->apr_new);
return -1;
}
aps->aps_nat = nat;
aps->aps_next = softp->ips_sess_list;
softp->ips_sess_list = aps;
nat->nat_aps = aps;
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_check */
/* Returns: int - -1 == error, 0 == success */
/* Parameters: fin(I) - pointer to packet information */
/* nat(I) - pointer to current NAT session */
/* */
/* Check to see if a packet should be passed through an active proxy */
/* routine if one has been setup for it. We don't need to check the */
/* checksum here if IPFILTER_CKSUM is defined because if it is, a failed */
/* check causes FI_BAD to be set. */
/* ------------------------------------------------------------------------ */
int
ipf_proxy_check(fin, nat)
fr_info_t *fin;
nat_t *nat;
{
ipf_main_softc_t *softc = fin->fin_main_soft;
ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
#if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
mb_t *m;
#endif
tcphdr_t *tcp = NULL;
udphdr_t *udp = NULL;
ap_session_t *aps;
aproxy_t *apr;
short adjlen;
int dosum;
ip_t *ip;
short rv;
int err;
#if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi)
u_32_t s1, s2, sd;
#endif
if (fin->fin_flx & FI_BAD) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_check: flx 0x%x (BAD)\n",
fin->fin_flx);
return -1;
}
#ifndef IPFILTER_CKSUM
if ((fin->fin_out == 0) && (ipf_checkl4sum(fin) == -1)) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_check: l4 checksum failure %d\n",
fin->fin_p);
if (fin->fin_p == IPPROTO_TCP)
softc->ipf_stats[fin->fin_out].fr_tcpbad++;
return -1;
}
#endif
aps = nat->nat_aps;
if (aps != NULL) {
/*
* If there is data in this packet to be proxied then try and
* get it all into the one buffer, else drop it.
*/
#if defined(MENTAT) || defined(HAVE_M_PULLDOWN)
if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE))
if (ipf_coalesce(fin) == -1) {
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_check: %s %x\n",
"coalesce failed", fin->fin_flx);
return -1;
}
#endif
ip = fin->fin_ip;
if (fin->fin_cksum > FI_CK_SUMOK)
dosum = 0;
else
dosum = 1;
switch (fin->fin_p)
{
case IPPROTO_TCP :
tcp = (tcphdr_t *)fin->fin_dp;
#if SOLARIS && defined(_KERNEL) && defined(ICK_VALID)
m = fin->fin_qfm;
if (dohwcksum && (m->b_ick_flag == ICK_VALID))
dosum = 0;
#endif
break;
case IPPROTO_UDP :
udp = (udphdr_t *)fin->fin_dp;
break;
default :
break;
}
apr = aps->aps_apr;
err = 0;
if (fin->fin_out != 0) {
if (apr->apr_outpkt != NULL)
err = (*apr->apr_outpkt)(apr->apr_soft, fin,
aps, nat);
} else {
if (apr->apr_inpkt != NULL)
err = (*apr->apr_inpkt)(apr->apr_soft, fin,
aps, nat);
}
rv = APR_EXIT(err);
if (((softp->ips_proxy_debug & 0x08) && (rv != 0)) ||
(softp->ips_proxy_debug & 0x04))
printf("ipf_proxy_check: out %d err %x rv %d\n",
fin->fin_out, err, rv);
if (rv == 1)
return -1;
if (rv == 2) {
ipf_proxy_deref(apr);
nat->nat_aps = NULL;
return -1;
}
/*
* If err != 0 then the data size of the packet has changed
* so we need to recalculate the header checksums for the
* packet.
*/
adjlen = APR_INC(err);
#if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi)
s1 = LONG_SUM(fin->fin_plen - adjlen);
s2 = LONG_SUM(fin->fin_plen);
CALC_SUMD(s1, s2, sd);
if ((err != 0) && (fin->fin_cksum < FI_CK_L4PART) &&
fin->fin_v == 4)
ipf_fix_outcksum(0, &ip->ip_sum, sd, 0);
#endif
if (fin->fin_flx & FI_DOCKSUM)
dosum = 1;
/*
* For TCP packets, we may need to adjust the sequence and
* acknowledgement numbers to reflect changes in size of the
* data stream.
*
* For both TCP and UDP, recalculate the layer 4 checksum,
* regardless, as we can't tell (here) if data has been
* changed or not.
*/
if (tcp != NULL) {
err = ipf_proxy_fixseqack(fin, ip, aps, adjlen);
if (fin->fin_cksum == FI_CK_L4PART) {
u_short sum = ntohs(tcp->th_sum);
sum += adjlen;
tcp->th_sum = htons(sum);
} else if (fin->fin_cksum < FI_CK_L4PART) {
tcp->th_sum = fr_cksum(fin, ip,
IPPROTO_TCP, tcp);
}
} else if ((udp != NULL) && (udp->uh_sum != 0)) {
if (fin->fin_cksum == FI_CK_L4PART) {
u_short sum = ntohs(udp->uh_sum);
sum += adjlen;
udp->uh_sum = htons(sum);
} else if (dosum) {
udp->uh_sum = fr_cksum(fin, ip,
IPPROTO_UDP, udp);
}
}
aps->aps_bytes += fin->fin_plen;
aps->aps_pkts++;
return 1;
}
return 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_lookup */
/* Returns: int - -1 == error, 0 == success */
/* Parameters: arg(I) - pointer to proxy context information */
/* pr(I) - protocol number for proxy */
/* name(I) - proxy name */
/* */
/* Search for an proxy by the protocol it is being used with and its name. */
/* ------------------------------------------------------------------------ */
aproxy_t *
ipf_proxy_lookup(arg, pr, name)
void *arg;
u_int pr;
char *name;
{
ipf_proxy_softc_t *softp = arg;
aproxy_t *ap;
if (softp->ips_proxy_debug & 0x04)
printf("ipf_proxy_lookup(%d,%s)\n", pr, name);
for (ap = softp->ips_proxies; ap != NULL; ap = ap->apr_next)
if ((ap->apr_p == pr) &&
!strncmp(name, ap->apr_label, sizeof(ap->apr_label))) {
ap->apr_ref++;
return ap;
}
if (softp->ips_proxy_debug & 0x08)
printf("ipf_proxy_lookup: failed for %d/%s\n", pr, name);
return NULL;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_deref */
/* Returns: Nil */
/* Parameters: ap(I) - pointer to proxy structure */
/* */
/* Drop the reference counter associated with the proxy. */
/* ------------------------------------------------------------------------ */
void
ipf_proxy_deref(ap)
aproxy_t *ap;
{
ap->apr_ref--;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_free */
/* Returns: Nil */
/* Parameters: softc(I) - pointer to soft context main structure */
/* aps(I) - pointer to current proxy session */
/* Locks Held: ipf_nat_new, ipf_nat(W) */
/* */
/* Free up proxy session information allocated to be used with a NAT */
/* session. */
/* ------------------------------------------------------------------------ */
void
ipf_proxy_free(softc, aps)
ipf_main_softc_t *softc;
ap_session_t *aps;
{
ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
ap_session_t *a, **ap;
aproxy_t *apr;
if (!aps)
return;
for (ap = &softp->ips_sess_list; ((a = *ap) != NULL); ap = &a->aps_next)
if (a == aps) {
*ap = a->aps_next;
break;
}
apr = aps->aps_apr;
if ((apr != NULL) && (apr->apr_del != NULL))
(*apr->apr_del)(softc, aps);
if ((aps->aps_data != NULL) && (aps->aps_psiz != 0))
KFREES(aps->aps_data, aps->aps_psiz);
KFREE(aps);
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_fixseqack */
/* Returns: int - 2 if TCP ack/seq is changed, else 0 */
/* Parameters: fin(I) - pointer to packet information */
/* ip(I) - pointer to IP header */
/* nat(I) - pointer to current NAT session */
/* inc(I) - delta to apply to TCP sequence numbering */
/* */
/* Adjust the TCP sequence/acknowledge numbers in the TCP header based on */
/* whether or not the new header is past the point at which an adjustment */
/* occurred. This might happen because of (say) an FTP string being changed */
/* and the new string being a different length to the old. */
/* ------------------------------------------------------------------------ */
static int
ipf_proxy_fixseqack(fin, ip, aps, inc)
fr_info_t *fin;
ip_t *ip;
ap_session_t *aps;
int inc;
{
ipf_main_softc_t *softc = fin->fin_main_soft;
ipf_proxy_softc_t *softp = softc->ipf_proxy_soft;
int sel, ch = 0, out, nlen;
u_32_t seq1, seq2;
tcphdr_t *tcp;
short inc2;
tcp = (tcphdr_t *)fin->fin_dp;
out = fin->fin_out;
/*
* ip_len has already been adjusted by 'inc'.
*/
nlen = fin->fin_dlen;
nlen -= (TCP_OFF(tcp) << 2);
inc2 = inc;
inc = (int)inc2;
if (out != 0) {
seq1 = (u_32_t)ntohl(tcp->th_seq);
sel = aps->aps_sel[out];
/* switch to other set ? */
if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
(seq1 > aps->aps_seqmin[!sel])) {
if (softp->ips_proxy_debug & 0x10)
printf("proxy out switch set seq %d -> %d %x > %x\n",
sel, !sel, seq1,
aps->aps_seqmin[!sel]);
sel = aps->aps_sel[out] = !sel;
}
if (aps->aps_seqoff[sel]) {
seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel];
if (seq1 > seq2) {
seq2 = aps->aps_seqoff[sel];
seq1 += seq2;
tcp->th_seq = htonl(seq1);
ch = 1;
}
}
if (inc && (seq1 > aps->aps_seqmin[!sel])) {
aps->aps_seqmin[sel] = seq1 + nlen - 1;
aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc;
if (softp->ips_proxy_debug & 0x10)
printf("proxy seq set %d at %x to %d + %d\n",
sel, aps->aps_seqmin[sel],
aps->aps_seqoff[sel], inc);
}
/***/
seq1 = ntohl(tcp->th_ack);
sel = aps->aps_sel[1 - out];
/* switch to other set ? */
if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
(seq1 > aps->aps_ackmin[!sel])) {
if (softp->ips_proxy_debug & 0x10)
printf("proxy out switch set ack %d -> %d %x > %x\n",
sel, !sel, seq1,
aps->aps_ackmin[!sel]);
sel = aps->aps_sel[1 - out] = !sel;
}
if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) {
seq2 = aps->aps_ackoff[sel];
tcp->th_ack = htonl(seq1 - seq2);
ch = 1;
}
} else {
seq1 = ntohl(tcp->th_seq);
sel = aps->aps_sel[out];
/* switch to other set ? */
if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) &&
(seq1 > aps->aps_ackmin[!sel])) {
if (softp->ips_proxy_debug & 0x10)
printf("proxy in switch set ack %d -> %d %x > %x\n",
sel, !sel, seq1, aps->aps_ackmin[!sel]);
sel = aps->aps_sel[out] = !sel;
}
if (aps->aps_ackoff[sel]) {
seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel];
if (seq1 > seq2) {
seq2 = aps->aps_ackoff[sel];
seq1 += seq2;
tcp->th_seq = htonl(seq1);
ch = 1;
}
}
if (inc && (seq1 > aps->aps_ackmin[!sel])) {
aps->aps_ackmin[!sel] = seq1 + nlen - 1;
aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc;
if (softp->ips_proxy_debug & 0x10)
printf("proxy ack set %d at %x to %d + %d\n",
!sel, aps->aps_seqmin[!sel],
aps->aps_seqoff[sel], inc);
}
/***/
seq1 = ntohl(tcp->th_ack);
sel = aps->aps_sel[1 - out];
/* switch to other set ? */
if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) &&
(seq1 > aps->aps_seqmin[!sel])) {
if (softp->ips_proxy_debug & 0x10)
printf("proxy in switch set seq %d -> %d %x > %x\n",
sel, !sel, seq1, aps->aps_seqmin[!sel]);
sel = aps->aps_sel[1 - out] = !sel;
}
if (aps->aps_seqoff[sel] != 0) {
if (softp->ips_proxy_debug & 0x10)
printf("sel %d seqoff %d seq1 %x seqmin %x\n",
sel, aps->aps_seqoff[sel], seq1,
aps->aps_seqmin[sel]);
if (seq1 > aps->aps_seqmin[sel]) {
seq2 = aps->aps_seqoff[sel];
tcp->th_ack = htonl(seq1 - seq2);
ch = 1;
}
}
}
if (softp->ips_proxy_debug & 0x10)
printf("ipf_proxy_fixseqack: seq %u ack %u\n",
(u_32_t)ntohl(tcp->th_seq), (u_32_t)ntohl(tcp->th_ack));
return ch ? 2 : 0;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_rule_rev */
/* Returns: ipnat_t * - NULL = failure, else pointer to new rule */
/* Parameters: nat(I) - pointer to NAT session to create rule from */
/* */
/* This function creates a NAT rule that is based upon the reverse packet */
/* flow associated with this NAT session. Thus if this NAT session was */
/* created with a map rule then this function will create a rdr rule. */
/* Only address fields and network interfaces are assigned in this function */
/* and the address fields are formed such that an exact is required. If the */
/* original rule had a netmask, that is not replicated here not is it */
/* desired. The ultimate goal here is to create a NAT rule to support a NAT */
/* session being created that does not have a user configured rule. The */
/* classic example is supporting the FTP proxy, where a data channel needs */
/* to be setup, based on the addresses used for the control connection. In */
/* that case, this function is used to handle creating NAT rules to support */
/* data connections with the PORT and EPRT commands. */
/* ------------------------------------------------------------------------ */
ipnat_t *
ipf_proxy_rule_rev(nat)
nat_t *nat;
{
ipnat_t *old;
ipnat_t *ipn;
int size;
old = nat->nat_ptr;
size = old->in_size;
KMALLOCS(ipn, ipnat_t *, size);
if (ipn == NULL)
return NULL;
bzero((char *)ipn, size);
ipn->in_use = 1;
ipn->in_hits = 1;
ipn->in_ippip = 1;
ipn->in_apr = NULL;
ipn->in_size = size;
ipn->in_pr[0] = old->in_pr[1];
ipn->in_pr[1] = old->in_pr[0];
ipn->in_v[0] = old->in_v[1];
ipn->in_v[1] = old->in_v[0];
ipn->in_ifps[0] = old->in_ifps[1];
ipn->in_ifps[1] = old->in_ifps[0];
ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
ipn->in_nsrcip6 = nat->nat_odst6;
ipn->in_osrcip6 = nat->nat_ndst6;
if ((old->in_redir & NAT_REDIRECT) != 0) {
ipn->in_redir = NAT_MAP;
if (ipn->in_v[0] == 4) {
ipn->in_snip = ntohl(nat->nat_odstaddr);
ipn->in_dnip = ntohl(nat->nat_nsrcaddr);
} else {
#ifdef USE_INET6
ipn->in_snip6 = nat->nat_odst6;
ipn->in_dnip6 = nat->nat_nsrc6;
#endif
}
ipn->in_ndstip6 = nat->nat_nsrc6;
ipn->in_odstip6 = nat->nat_osrc6;
} else {
ipn->in_redir = NAT_REDIRECT;
if (ipn->in_v[0] == 4) {
ipn->in_snip = ntohl(nat->nat_odstaddr);
ipn->in_dnip = ntohl(nat->nat_osrcaddr);
} else {
#ifdef USE_INET6
ipn->in_snip6 = nat->nat_odst6;
ipn->in_dnip6 = nat->nat_osrc6;
#endif
}
ipn->in_ndstip6 = nat->nat_osrc6;
ipn->in_odstip6 = nat->nat_nsrc6;
}
IP6_SETONES(&ipn->in_osrcmsk6);
IP6_SETONES(&ipn->in_nsrcmsk6);
IP6_SETONES(&ipn->in_odstmsk6);
IP6_SETONES(&ipn->in_ndstmsk6);
ipn->in_namelen = old->in_namelen;
ipn->in_ifnames[0] = old->in_ifnames[1];
ipn->in_ifnames[1] = old->in_ifnames[0];
bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
MUTEX_INIT(&ipn->in_lock, "ipnat rev rule lock");
return ipn;
}
/* ------------------------------------------------------------------------ */
/* Function: ipf_proxy_rule_fwd */
/* Returns: ipnat_t * - NULL = failure, else pointer to new rule */
/* Parameters: nat(I) - pointer to NAT session to create rule from */
/* */
/* The purpose and rationale of this function is much the same as the above */
/* function, ipf_proxy_rule_rev, except that a rule is created that matches */
/* the same direction as that of the existing NAT session. Thus if this NAT */
/* session was created with a map rule then this function will also create */
/* a data structure to represent a map rule. Whereas ipf_proxy_rule_rev is */
/* used to support PORT/EPRT, this function supports PASV/EPSV. */
/* ------------------------------------------------------------------------ */
ipnat_t *
ipf_proxy_rule_fwd(nat)
nat_t *nat;
{
ipnat_t *old;
ipnat_t *ipn;
int size;
old = nat->nat_ptr;
size = old->in_size;
KMALLOCS(ipn, ipnat_t *, size);
if (ipn == NULL)
return NULL;
bzero((char *)ipn, size);
ipn->in_use = 1;
ipn->in_hits = 1;
ipn->in_ippip = 1;
ipn->in_apr = NULL;
ipn->in_size = size;
ipn->in_pr[0] = old->in_pr[0];
ipn->in_pr[1] = old->in_pr[1];
ipn->in_v[0] = old->in_v[0];
ipn->in_v[1] = old->in_v[1];
ipn->in_ifps[0] = nat->nat_ifps[0];
ipn->in_ifps[1] = nat->nat_ifps[1];
ipn->in_flags = (old->in_flags | IPN_PROXYRULE);
ipn->in_nsrcip6 = nat->nat_nsrc6;
ipn->in_osrcip6 = nat->nat_osrc6;
ipn->in_ndstip6 = nat->nat_ndst6;
ipn->in_odstip6 = nat->nat_odst6;
ipn->in_redir = old->in_redir;
if (ipn->in_v[0] == 4) {
ipn->in_snip = ntohl(nat->nat_nsrcaddr);
ipn->in_dnip = ntohl(nat->nat_ndstaddr);
} else {
#ifdef USE_INET6
ipn->in_snip6 = nat->nat_nsrc6;
ipn->in_dnip6 = nat->nat_ndst6;
#endif
}
IP6_SETONES(&ipn->in_osrcmsk6);
IP6_SETONES(&ipn->in_nsrcmsk6);
IP6_SETONES(&ipn->in_odstmsk6);
IP6_SETONES(&ipn->in_ndstmsk6);
ipn->in_namelen = old->in_namelen;
ipn->in_ifnames[0] = old->in_ifnames[0];
ipn->in_ifnames[1] = old->in_ifnames[1];
bcopy(old->in_names, ipn->in_names, ipn->in_namelen);
MUTEX_INIT(&ipn->in_lock, "ipnat fwd rule lock");
return ipn;
}