303 lines
7.1 KiB
C
303 lines
7.1 KiB
C
/* $NetBSD: ip_h323_pxy.c,v 1.1 2004/10/02 07:51:53 christos Exp $ */
|
|
|
|
/*
|
|
* Copyright 2001, QNX Software Systems Ltd. All Rights Reserved
|
|
*
|
|
* This source code has been published by QNX Software Systems Ltd. (QSSL).
|
|
* However, any use, reproduction, modification, distribution or transfer of
|
|
* this software, or any software which includes or is based upon any of this
|
|
* code, is only permitted under the terms of the QNX Open Community License
|
|
* version 1.0 (see licensing.qnx.com for details) or as otherwise expressly
|
|
* authorized by a written license agreement from QSSL. For more information,
|
|
* please email licensing@qnx.com.
|
|
*
|
|
* For more details, see QNX_OCL.txt provided with this distribution.
|
|
*/
|
|
|
|
/*
|
|
* Simple H.323 proxy
|
|
*
|
|
* by xtang@canada.com
|
|
* ported to ipfilter 3.4.20 by Michael Grant mg-ipf@grant.org
|
|
*/
|
|
|
|
#if __FreeBSD_version >= 220000 && defined(_KERNEL)
|
|
# include <sys/fcntl.h>
|
|
# include <sys/filio.h>
|
|
#else
|
|
# ifndef linux
|
|
# include <sys/ioctl.h>
|
|
# endif
|
|
#endif
|
|
|
|
#ifdef _KERNEL_OPT
|
|
#include "opt_ipfilter_log.h"
|
|
#endif
|
|
|
|
__KERNEL_RCSID(1, "$NetBSD: ip_h323_pxy.c,v 1.1 2004/10/02 07:51:53 christos Exp $");
|
|
|
|
#define IPF_H323_PROXY
|
|
|
|
int ippr_h323_init __P((void));
|
|
void ippr_h323_fini __P((void));
|
|
int ippr_h323_new __P((fr_info_t *, ap_session_t *, nat_t *));
|
|
void ippr_h323_del __P((ap_session_t *));
|
|
int ippr_h323_out __P((fr_info_t *, ap_session_t *, nat_t *));
|
|
int ippr_h323_in __P((fr_info_t *, ap_session_t *, nat_t *));
|
|
|
|
int ippr_h245_new __P((fr_info_t *, ap_session_t *, nat_t *));
|
|
int ippr_h245_out __P((fr_info_t *, ap_session_t *, nat_t *));
|
|
int ippr_h245_in __P((fr_info_t *, ap_session_t *, nat_t *));
|
|
|
|
static frentry_t h323_fr;
|
|
|
|
int h323_proxy_init = 0;
|
|
|
|
static int find_port __P((int, caddr_t, int datlen, int *, u_short *));
|
|
|
|
|
|
static int find_port(ipaddr, data, datlen, off, port)
|
|
int ipaddr;
|
|
caddr_t data;
|
|
int datlen, *off;
|
|
unsigned short *port;
|
|
{
|
|
u_32_t addr, netaddr;
|
|
u_char *dp;
|
|
int offset;
|
|
|
|
if (datlen < 6)
|
|
return -1;
|
|
|
|
*port = 0;
|
|
offset = *off;
|
|
dp = (u_char *)data;
|
|
netaddr = ntohl(ipaddr);
|
|
|
|
for (offset = 0; offset <= datlen - 6; offset++, dp++) {
|
|
addr = (dp[0] << 24) | (dp[1] << 16) | (dp[2] << 8) | dp[3];
|
|
if (netaddr == addr)
|
|
{
|
|
*port = (*(dp + 4) << 8) | *(dp + 5);
|
|
break;
|
|
}
|
|
}
|
|
*off = offset;
|
|
return (offset > datlen - 6) ? -1 : 0;
|
|
}
|
|
|
|
/*
|
|
* Initialize local structures.
|
|
*/
|
|
int ippr_h323_init()
|
|
{
|
|
bzero((char *)&h323_fr, sizeof(h323_fr));
|
|
h323_fr.fr_ref = 1;
|
|
h323_fr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
|
|
MUTEX_INIT(&h323_fr.fr_lock, "H323 proxy rule lock");
|
|
h323_proxy_init = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void ippr_h323_fini()
|
|
{
|
|
if (h323_proxy_init == 1) {
|
|
MUTEX_DESTROY(&h323_fr.fr_lock);
|
|
h323_proxy_init = 0;
|
|
}
|
|
}
|
|
|
|
|
|
int ippr_h323_new(fin, aps, nat)
|
|
fr_info_t *fin;
|
|
ap_session_t *aps;
|
|
nat_t *nat;
|
|
{
|
|
fin = fin; /* LINT */
|
|
nat = nat; /* LINT */
|
|
|
|
aps->aps_data = NULL;
|
|
aps->aps_psiz = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void ippr_h323_del(aps)
|
|
ap_session_t *aps;
|
|
{
|
|
int i;
|
|
ipnat_t *ipn;
|
|
|
|
if (aps->aps_data) {
|
|
for (i = 0, ipn = aps->aps_data;
|
|
i < (aps->aps_psiz / sizeof(ipnat_t));
|
|
i++, ipn = (ipnat_t *)((char *)ipn + sizeof(*ipn)))
|
|
{
|
|
/*
|
|
* Check the comment in ippr_h323_in() function,
|
|
* just above fr_nat_ioctl() call.
|
|
* We are lucky here because this function is not
|
|
* called with ipf_nat locked.
|
|
*/
|
|
if (fr_nat_ioctl((caddr_t)ipn, SIOCRMNAT, NAT_SYSSPACE|
|
|
NAT_LOCKHELD|FWRITE) == -1) {
|
|
/*EMPTY*/;
|
|
/* log the error */
|
|
}
|
|
}
|
|
KFREES(aps->aps_data, aps->aps_psiz);
|
|
/* avoid double free */
|
|
aps->aps_data = NULL;
|
|
aps->aps_psiz = 0;
|
|
}
|
|
return;
|
|
}
|
|
|
|
|
|
int ippr_h323_in(fin, aps, nat)
|
|
fr_info_t *fin;
|
|
ap_session_t *aps;
|
|
nat_t *nat;
|
|
{
|
|
int ipaddr, off, datlen;
|
|
unsigned short port;
|
|
caddr_t data;
|
|
tcphdr_t *tcp;
|
|
ip_t *ip;
|
|
|
|
ip = fin->fin_ip;
|
|
tcp = (tcphdr_t *)fin->fin_dp;
|
|
ipaddr = ip->ip_src.s_addr;
|
|
|
|
data = (caddr_t)tcp + (TCP_OFF(tcp) << 2);
|
|
datlen = fin->fin_dlen - (TCP_OFF(tcp) << 2);
|
|
if (find_port(ipaddr, data, datlen, &off, &port) == 0) {
|
|
ipnat_t *ipn;
|
|
char *newarray;
|
|
|
|
/* setup a nat rule to set a h245 proxy on tcp-port "port"
|
|
* it's like:
|
|
* map <if> <inter_ip>/<mask> -> <gate_ip>/<mask> proxy port <port> <port>/tcp
|
|
*/
|
|
KMALLOCS(newarray, char *, aps->aps_psiz + sizeof(*ipn));
|
|
if (newarray == NULL) {
|
|
return -1;
|
|
}
|
|
ipn = (ipnat_t *)&newarray[aps->aps_psiz];
|
|
bcopy((caddr_t)nat->nat_ptr, (caddr_t)ipn, sizeof(ipnat_t));
|
|
(void) strncpy(ipn->in_plabel, "h245", APR_LABELLEN);
|
|
|
|
ipn->in_inip = nat->nat_inip.s_addr;
|
|
ipn->in_inmsk = 0xffffffff;
|
|
ipn->in_dport = htons(port);
|
|
/*
|
|
* we got a problem here. we need to call fr_nat_ioctl() to add
|
|
* the h245 proxy rule, but since we already hold (READ locked)
|
|
* the nat table rwlock (ipf_nat), if we go into fr_nat_ioctl(),
|
|
* it will try to WRITE lock it. This will causing dead lock
|
|
* on RTP.
|
|
*
|
|
* The quick & dirty solution here is release the read lock,
|
|
* call fr_nat_ioctl() and re-lock it.
|
|
* A (maybe better) solution is do a UPGRADE(), and instead
|
|
* of calling fr_nat_ioctl(), we add the nat rule ourself.
|
|
*/
|
|
RWLOCK_EXIT(&ipf_nat);
|
|
if (fr_nat_ioctl((caddr_t)ipn, SIOCADNAT,
|
|
NAT_SYSSPACE|FWRITE) == -1) {
|
|
READ_ENTER(&ipf_nat);
|
|
return -1;
|
|
}
|
|
READ_ENTER(&ipf_nat);
|
|
if (aps->aps_data != NULL && aps->aps_psiz > 0) {
|
|
bcopy(aps->aps_data, newarray, aps->aps_psiz);
|
|
KFREES(aps->aps_data, aps->aps_psiz);
|
|
}
|
|
aps->aps_data = newarray;
|
|
aps->aps_psiz += sizeof(*ipn);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
int ippr_h245_new(fin, aps, nat)
|
|
fr_info_t *fin;
|
|
ap_session_t *aps;
|
|
nat_t *nat;
|
|
{
|
|
fin = fin; /* LINT */
|
|
nat = nat; /* LINT */
|
|
|
|
aps->aps_data = NULL;
|
|
aps->aps_psiz = 0;
|
|
return 0;
|
|
}
|
|
|
|
|
|
int ippr_h245_out(fin, aps, nat)
|
|
fr_info_t *fin;
|
|
ap_session_t *aps;
|
|
nat_t *nat;
|
|
{
|
|
int ipaddr, off, datlen;
|
|
tcphdr_t *tcp;
|
|
caddr_t data;
|
|
u_short port;
|
|
ip_t *ip;
|
|
|
|
aps = aps; /* LINT */
|
|
|
|
ip = fin->fin_ip;
|
|
tcp = (tcphdr_t *)fin->fin_dp;
|
|
ipaddr = nat->nat_inip.s_addr;
|
|
data = (caddr_t)tcp + (TCP_OFF(tcp) << 2);
|
|
datlen = ip->ip_len - fin->fin_hlen - (TCP_OFF(tcp) << 2);
|
|
if (find_port(ipaddr, data, datlen, &off, &port) == 0) {
|
|
fr_info_t fi;
|
|
nat_t *nat2;
|
|
|
|
/* port = htons(port); */
|
|
nat2 = nat_outlookup(fin->fin_ifp, IPN_UDP, IPPROTO_UDP,
|
|
ip->ip_src, ip->ip_dst);
|
|
if (nat2 == NULL) {
|
|
struct ip newip;
|
|
struct udphdr udp;
|
|
|
|
bcopy((caddr_t)ip, (caddr_t)&newip, sizeof(newip));
|
|
newip.ip_len = fin->fin_hlen + sizeof(udp);
|
|
newip.ip_p = IPPROTO_UDP;
|
|
newip.ip_src = nat->nat_inip;
|
|
|
|
bzero((char *)&udp, sizeof(udp));
|
|
udp.uh_sport = port;
|
|
|
|
bcopy((caddr_t)fin, (caddr_t)&fi, sizeof(fi));
|
|
fi.fin_fi.fi_p = IPPROTO_UDP;
|
|
fi.fin_data[0] = port;
|
|
fi.fin_data[1] = 0;
|
|
fi.fin_dp = (char *)&udp;
|
|
|
|
nat2 = nat_new(&fi, nat->nat_ptr, NULL,
|
|
NAT_SLAVE|IPN_UDP|SI_W_DPORT,
|
|
NAT_OUTBOUND);
|
|
if (nat2 != NULL) {
|
|
(void) nat_proto(&fi, nat2, IPN_UDP);
|
|
nat_update(&fi, nat2, nat2->nat_ptr);
|
|
|
|
nat2->nat_ptr->in_hits++;
|
|
#ifdef IPFILTER_LOG
|
|
nat_log(nat2, (u_int)(nat->nat_ptr->in_redir));
|
|
#endif
|
|
bcopy((caddr_t)&ip->ip_src.s_addr,
|
|
data + off, 4);
|
|
bcopy((caddr_t)&nat2->nat_outport,
|
|
data + off + 4, 2);
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|