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freebsd/ip_h323_pxy.c
Cy Schubert f27f47054d As per the developers handbook (5.3.1 step 1), prepare the vendor trees for
import of new ipfilter vendor sources by flattening them.

To keep the tags consistent with dist, the tags are also flattened.

Approved by:	glebius (Mentor)
2013-07-19 05:41:57 +00:00

297 lines
6.9 KiB
C

/* $NetBSD$ */
/*
* 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
#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;
}