blob: 3f9b20a3cfa6d9e26aa2e3493e9c12148904adb1 [file] [log] [blame] [raw]
/*
* Copyright (C) 1997-2003 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>
# if (__FreeBSD_version >= 300000) && !defined(IPFILTER_LKM)
# include "opt_ipfilter.h"
# endif
#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_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_h323_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
static int appr_fixseqack __P((fr_info_t *, ip_t *, ap_session_t *, int ));
#define AP_SESS_SIZE 53
#if defined(_KERNEL)
int ipf_proxy_debug = 0;
#else
int ipf_proxy_debug = 2;
#endif
ap_session_t *ap_sess_tab[AP_SESS_SIZE];
ap_session_t *ap_sess_list = NULL;
aproxy_t *ap_proxylist = NULL;
aproxy_t ap_proxies[] = {
#ifdef IPF_FTP_PROXY
{ NULL, "ftp", (char)IPPROTO_TCP, 0, 0, ippr_ftp_init, ippr_ftp_fini,
ippr_ftp_new, NULL, ippr_ftp_in, ippr_ftp_out, NULL, NULL },
#endif
#ifdef IPF_IRC_PROXY
{ NULL, "irc", (char)IPPROTO_TCP, 0, 0, ippr_irc_init, ippr_irc_fini,
ippr_irc_new, NULL, NULL, ippr_irc_out, NULL, NULL },
#endif
#ifdef IPF_RCMD_PROXY
{ NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, ippr_rcmd_init, ippr_rcmd_fini,
ippr_rcmd_new, NULL, ippr_rcmd_in, ippr_rcmd_out, NULL, NULL },
#endif
#ifdef IPF_RAUDIO_PROXY
{ NULL, "raudio", (char)IPPROTO_TCP, 0, 0, ippr_raudio_init, ippr_raudio_fini,
ippr_raudio_new, NULL, ippr_raudio_in, ippr_raudio_out, NULL, NULL },
#endif
#ifdef IPF_MSNRPC_PROXY
{ NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, ippr_msnrpc_init, ippr_msnrpc_fini,
ippr_msnrpc_new, NULL, ippr_msnrpc_in, ippr_msnrpc_out, NULL, NULL },
#endif
#ifdef IPF_NETBIOS_PROXY
{ NULL, "netbios", (char)IPPROTO_UDP, 0, 0, ippr_netbios_init, ippr_netbios_fini,
NULL, NULL, NULL, ippr_netbios_out, NULL, NULL },
#endif
#ifdef IPF_IPSEC_PROXY
{ NULL, "ipsec", (char)IPPROTO_UDP, 0, 0,
ippr_ipsec_init, ippr_ipsec_fini, ippr_ipsec_new, ippr_ipsec_del,
ippr_ipsec_inout, ippr_ipsec_inout, ippr_ipsec_match, NULL },
#endif
#ifdef IPF_PPTP_PROXY
{ NULL, "pptp", (char)IPPROTO_TCP, 0, 0,
ippr_pptp_init, ippr_pptp_fini, ippr_pptp_new, ippr_pptp_del,
ippr_pptp_inout, ippr_pptp_inout, NULL, NULL },
#endif
#ifdef IPF_H323_PROXY
{ NULL, "h323", (char)IPPROTO_TCP, 0, 0, ippr_h323_init, ippr_h323_fini,
ippr_h323_new, ippr_h323_del, ippr_h323_in, NULL, NULL, NULL },
{ NULL, "h245", (char)IPPROTO_TCP, 0, 0, NULL, NULL,
ippr_h245_new, NULL, NULL, ippr_h245_out, NULL, NULL },
#endif
#ifdef IPF_RPCB_PROXY
# if 0
{ NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0,
ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del,
ippr_rpcb_in, ippr_rpcb_out, NULL, NULL },
# endif
{ NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0,
ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del,
ippr_rpcb_in, ippr_rpcb_out, NULL, NULL },
#endif
{ NULL, "", '\0', 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL }
};
/*
* Dynamically add a new kernel proxy. Ensure that it is unique in the
* collection compiled in and dynamically added.
*/
int appr_add(ap)
aproxy_t *ap;
{
aproxy_t *a;
for (a = ap_proxies; a->apr_p; a++)
if ((a->apr_p == ap->apr_p) &&
!strncmp(a->apr_label, ap->apr_label,
sizeof(ap->apr_label))) {
if (ipf_proxy_debug > 1)
printf("appr_add: %s/%d already 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 (ipf_proxy_debug > 1)
printf("appr_add: %s/%d already present (D)\n",
a->apr_label, a->apr_p);
return -1;
}
ap->apr_next = ap_proxylist;
ap_proxylist = ap;
if (ap->apr_init != NULL)
return (*ap->apr_init)();
return 0;
}
/*
* 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 appr_ctl(ctl)
ap_ctl_t *ctl;
{
aproxy_t *a;
int error;
a = appr_lookup(ctl->apc_p, ctl->apc_label);
if (a == NULL) {
if (ipf_proxy_debug > 1)
printf("appr_ctl: can't find %s/%d\n",
ctl->apc_label, ctl->apc_p);
error = ESRCH;
} else if (a->apr_ctl == NULL) {
if (ipf_proxy_debug > 1)
printf("appr_ctl: no ctl function for %s/%d\n",
ctl->apc_label, ctl->apc_p);
error = ENXIO;
} else {
error = (*a->apr_ctl)(a, ctl);
if ((error != 0) && (ipf_proxy_debug > 1))
printf("appr_ctl: %s/%d ctl error %d\n",
a->apr_label, a->apr_p, error);
}
return error;
}
/*
* 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 appr_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;
*app = a->apr_next;
if (ap->apr_ref != 0) {
if (ipf_proxy_debug > 2)
printf("appr_del: orphaning %s/%d\n",
ap->apr_label, ap->apr_p);
return 1;
}
return 0;
}
if (ipf_proxy_debug > 1)
printf("appr_del: proxy %lx not found\n", (u_long)ap);
return -1;
}
/*
* Return 1 if the packet is a good match against a proxy, else 0.
*/
int appr_ok(fin, tcp, nat)
fr_info_t *fin;
tcphdr_t *tcp;
ipnat_t *nat;
{
aproxy_t *apr = nat->in_apr;
u_short dport = nat->in_dport;
if ((apr == NULL) || (apr->apr_flags & APR_DELETE) ||
(fin->fin_p != apr->apr_p))
return 0;
if ((tcp == NULL) && dport)
return 0;
return 1;
}
int appr_ioctl(data, cmd, mode, ctx)
caddr_t data;
ioctlcmd_t cmd;
int mode;
void *ctx;
{
ap_ctl_t ctl;
u_char *ptr;
int error;
mode = mode; /* LINT */
switch (cmd)
{
case SIOCPROXY :
error = BCOPYIN(data, &ctl, sizeof(ctl));
if (error != 0)
return EFAULT;
ptr = NULL;
if (ctl.apc_dsize > 0) {
KMALLOCS(ptr, u_char *, ctl.apc_dsize);
if (ptr == NULL)
error = ENOMEM;
else {
error = copyinptr(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 = appr_ctl(&ctl);
if (ptr != NULL) {
KFREES(ptr, ctl.apc_dsize);
}
break;
default :
error = EINVAL;
}
return error;
}
/*
* If a proxy has a match function, call that to do extended packet
* matching.
*/
int appr_match(fin, nat)
fr_info_t *fin;
nat_t *nat;
{
aproxy_t *apr;
ipnat_t *ipn;
int result;
ipn = nat->nat_ptr;
if (ipf_proxy_debug > 8)
printf("appr_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 (ipf_proxy_debug > 0)
printf("appr_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 (ipf_proxy_debug > 0)
printf("appr_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 (ipf_proxy_debug > 4)
printf("appr_match: result %d\n", result);
return -1;
}
}
return 0;
}
/*
* Allocate a new application proxy structure and fill it in with the
* relevant details. call the init function once complete, prior to
* returning.
*/
int appr_new(fin, nat)
fr_info_t *fin;
nat_t *nat;
{
register ap_session_t *aps;
aproxy_t *apr;
if (ipf_proxy_debug > 8)
printf("appr_new(%lx,%lx) \n", (u_long)fin, (u_long)nat);
if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) {
if (ipf_proxy_debug > 0)
printf("appr_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 (ipf_proxy_debug > 2)
printf("appr_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 (ipf_proxy_debug > 0)
printf("appr_new: malloc failed (%lu)\n",
(u_long)sizeof(ap_session_t));
return -1;
}
bzero((char *)aps, sizeof(*aps));
aps->aps_p = fin->fin_p;
aps->aps_data = NULL;
aps->aps_apr = apr;
aps->aps_psiz = 0;
if (apr->apr_new != NULL)
if ((*apr->apr_new)(fin, aps, nat) == -1) {
if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) {
KFREES(aps->aps_data, aps->aps_psiz);
}
KFREE(aps);
if (ipf_proxy_debug > 2)
printf("appr_new: new(%lx) failed\n",
(u_long)apr->apr_new);
return -1;
}
aps->aps_nat = nat;
aps->aps_next = ap_sess_list;
ap_sess_list = aps;
nat->nat_aps = aps;
return 0;
}
/*
* 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 appr_check(fin, nat)
fr_info_t *fin;
nat_t *nat;
{
#if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6)
# if defined(ICK_VALID)
mb_t *m;
# endif
int dosum = 1;
#endif
tcphdr_t *tcp = NULL;
udphdr_t *udp = NULL;
ap_session_t *aps;
aproxy_t *apr;
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 (ipf_proxy_debug > 0)
printf("appr_check: flx 0x%x (BAD)\n", fin->fin_flx);
return -1;
}
#ifndef IPFILTER_CKSUM
if ((fin->fin_out == 0) && (fr_checkl4sum(fin) == -1)) {
if (ipf_proxy_debug > 0)
printf("appr_check: l4 checksum failure %d\n",
fin->fin_p);
if (fin->fin_p == IPPROTO_TCP)
frstats[fin->fin_out].fr_tcpbad++;
return -1;
}
#endif
aps = nat->nat_aps;
if ((aps != NULL) && (aps->aps_p == fin->fin_p)) {
/*
* 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 (fr_coalesce(fin) == -1) {
if (ipf_proxy_debug > 0)
printf("appr_check: fr_coalesce failed %x\n", fin->fin_flx);
return -1;
}
#endif
ip = fin->fin_ip;
switch (fin->fin_p)
{
case IPPROTO_TCP :
tcp = (tcphdr_t *)fin->fin_dp;
#if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID)
m = fin->fin_qfm;
if (dohwcksum && (m->b_ick_flag == ICK_VALID))
dosum = 0;
#endif
/*
* Don't bother the proxy with these...or in fact,
* should we free up proxy stuff when seen?
*/
if ((fin->fin_tcpf & TH_RST) != 0)
break;
/*FALLTHROUGH*/
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)(fin, aps, nat);
} else {
if (apr->apr_inpkt != NULL)
err = (*apr->apr_inpkt)(fin, aps, nat);
}
rv = APR_EXIT(err);
if (((ipf_proxy_debug > 0) && (rv != 0)) ||
(ipf_proxy_debug > 8))
printf("appr_check: out %d err %x rv %d\n",
fin->fin_out, err, rv);
if (rv == 1)
return -1;
if (rv == 2) {
appr_free(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.
*/
#if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi)
if (err != 0) {
short adjlen = err & 0xffff;
s1 = LONG_SUM(fin->fin_plen - adjlen);
s2 = LONG_SUM(fin->fin_plen);
CALC_SUMD(s1, s2, sd);
fix_outcksum(fin, &ip->ip_sum, sd);
}
#endif
/*
* 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 = appr_fixseqack(fin, ip, aps, APR_INC(err));
#if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6)
if (dosum)
tcp->th_sum = fr_cksum(fin->fin_qfm, ip,
IPPROTO_TCP, tcp,
fin->fin_plen);
#else
tcp->th_sum = fr_cksum(fin->fin_m, ip,
IPPROTO_TCP, tcp,
fin->fin_plen);
#endif
} else if ((udp != NULL) && (udp->uh_sum != 0)) {
#if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6)
if (dosum)
udp->uh_sum = fr_cksum(fin->fin_qfm, ip,
IPPROTO_UDP, udp,
fin->fin_plen);
#else
udp->uh_sum = fr_cksum(fin->fin_m, ip,
IPPROTO_UDP, udp,
fin->fin_plen);
#endif
}
aps->aps_bytes += fin->fin_plen;
aps->aps_pkts++;
return 1;
}
return 0;
}
/*
* Search for an proxy by the protocol it is being used with and its name.
*/
aproxy_t *appr_lookup(pr, name)
u_int pr;
char *name;
{
aproxy_t *ap;
if (ipf_proxy_debug > 8)
printf("appr_lookup(%d,%s)\n", pr, name);
for (ap = ap_proxies; ap->apr_p; ap++)
if ((ap->apr_p == pr) &&
!strncmp(name, ap->apr_label, sizeof(ap->apr_label))) {
ap->apr_ref++;
return ap;
}
for (ap = ap_proxylist; ap; ap = ap->apr_next)
if ((ap->apr_p == pr) &&
!strncmp(name, ap->apr_label, sizeof(ap->apr_label))) {
ap->apr_ref++;
return ap;
}
if (ipf_proxy_debug > 2)
printf("appr_lookup: failed for %d/%s\n", pr, name);
return NULL;
}
void appr_free(ap)
aproxy_t *ap;
{
ap->apr_ref--;
}
void aps_free(aps)
ap_session_t *aps;
{
ap_session_t *a, **ap;
aproxy_t *apr;
if (!aps)
return;
for (ap = &ap_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)(aps);
if ((aps->aps_data != NULL) && (aps->aps_psiz != 0))
KFREES(aps->aps_data, aps->aps_psiz);
KFREE(aps);
}
/*
* returns 2 if ack or seq number in TCP header is changed, returns 0 otherwise
*/
static int appr_fixseqack(fin, ip, aps, inc)
fr_info_t *fin;
ip_t *ip;
ap_session_t *aps;
int inc;
{
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;
/*
* fin->fin_plen has already been adjusted by 'inc'.
*/
nlen = fin->fin_plen;
nlen -= (IP_HL(ip) << 2) + (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 (ipf_proxy_debug > 7)
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 (ipf_proxy_debug > 7)
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 (ipf_proxy_debug > 7)
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 (ipf_proxy_debug > 7)
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 (ipf_proxy_debug > 7)
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 (ipf_proxy_debug > 7)
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 (ipf_proxy_debug > 7)
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 (ipf_proxy_debug > 8)
printf("appr_fixseqack: seq %x ack %x\n",
(u_32_t)ntohl(tcp->th_seq), (u_32_t)ntohl(tcp->th_ack));
return ch ? 2 : 0;
}
/*
* Initialise hook for kernel application proxies.
* Call the initialise routine for all the compiled in kernel proxies.
*/
int appr_init()
{
aproxy_t *ap;
int err = 0;
for (ap = ap_proxies; ap->apr_p; ap++) {
if (ap->apr_init != NULL) {
err = (*ap->apr_init)();
if (err != 0)
break;
}
}
return err;
}
/*
* Unload hook for kernel application proxies.
* Call the finialise routine for all the compiled in kernel proxies.
*/
void appr_unload()
{
aproxy_t *ap;
for (ap = ap_proxies; ap->apr_p; ap++)
if (ap->apr_fini != NULL)
(*ap->apr_fini)();
for (ap = ap_proxylist; ap; ap = ap->apr_next)
if (ap->apr_fini != NULL)
(*ap->apr_fini)();
}