static int
protohandler(struct libalias *la, struct ip *pip, struct alias_data *ah)
{
AliasHandleIrcOut(la, pip, ah->lnk, ah->maxpktsize);
return (0);
}
static int
protohandler(struct libalias *la, struct ip *pip, struct alias_data *ah)
{
newpacket = malloc(PKTSIZE);
if (newpacket) {
AliasHandleIrcOut(la, pip, ah->lnk, ah->maxpktsize);
free(newpacket);
}
return (0);
}
static int
protohandler(struct libalias *la, struct ip *pip, struct alias_data *ah)
{
newpacket = kmalloc(PKTSIZE,M_ALIAS, M_WAITOK | M_ZERO);
if (newpacket) {
AliasHandleIrcOut(la, pip, ah->lnk, ah->maxpktsize);
kfree(newpacket,M_ALIAS);
}
return (0);
}
static int
TcpAliasOut(struct ip *pip, int maxpacketsize)
{
int proxy_type;
u_short dest_port;
u_short proxy_server_port;
struct in_addr dest_address;
struct in_addr proxy_server_address;
struct tcphdr *tc;
struct alias_link *link;
tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
proxy_type = ProxyCheck(pip, &proxy_server_address, &proxy_server_port);
if (proxy_type == 0 && (packetAliasMode & PKT_ALIAS_PROXY_ONLY))
return PKT_ALIAS_OK;
/* If this is a transparent proxy, save original destination,
then alter the destination and adjust checksums */
dest_port = tc->th_dport;
dest_address = pip->ip_dst;
if (proxy_type != 0)
{
int accumulate;
u_short *sptr;
accumulate = tc->th_dport;
tc->th_dport = proxy_server_port;
accumulate -= tc->th_dport;
sptr = (u_short *) &(pip->ip_dst);
accumulate += *sptr++;
accumulate += *sptr;
sptr = (u_short *) &proxy_server_address;
accumulate -= *sptr++;
accumulate -= *sptr;
ADJUST_CHECKSUM(accumulate, tc->th_sum);
sptr = (u_short *) &(pip->ip_dst);
accumulate = *sptr++;
accumulate += *sptr;
pip->ip_dst = proxy_server_address;
sptr = (u_short *) &(pip->ip_dst);
accumulate -= *sptr++;
accumulate -= *sptr;
ADJUST_CHECKSUM(accumulate, pip->ip_sum);
}
link = FindUdpTcpOut(pip->ip_src, pip->ip_dst,
tc->th_sport, tc->th_dport,
IPPROTO_TCP, 1);
if (link !=NULL)
{
u_short alias_port;
struct in_addr alias_address;
int accumulate;
u_short *sptr;
/* Save original destination address, if this is a proxy packet.
Also modify packet to include destination encoding. This may
change the size of IP header. */
if (proxy_type != 0)
{
SetProxyPort(link, dest_port);
SetProxyAddress(link, dest_address);
ProxyModify(link, pip, maxpacketsize, proxy_type);
tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
}
/* Get alias address and port */
alias_port = GetAliasPort(link);
alias_address = GetAliasAddress(link);
/* Monitor TCP connection state */
TcpMonitorOut(pip, link);
/* Special processing for IP encoding protocols */
if (ntohs(tc->th_dport) == FTP_CONTROL_PORT_NUMBER
|| ntohs(tc->th_sport) == FTP_CONTROL_PORT_NUMBER)
AliasHandleFtpOut(pip, link, maxpacketsize);
else if (ntohs(tc->th_dport) == IRC_CONTROL_PORT_NUMBER_1
|| ntohs(tc->th_dport) == IRC_CONTROL_PORT_NUMBER_2)
AliasHandleIrcOut(pip, link, maxpacketsize);
else if (ntohs(tc->th_dport) == RTSP_CONTROL_PORT_NUMBER_1
|| ntohs(tc->th_sport) == RTSP_CONTROL_PORT_NUMBER_1
|| ntohs(tc->th_dport) == RTSP_CONTROL_PORT_NUMBER_2
|| ntohs(tc->th_sport) == RTSP_CONTROL_PORT_NUMBER_2)
AliasHandleRtspOut(pip, link, maxpacketsize);
else if (ntohs(tc->th_dport) == PPTP_CONTROL_PORT_NUMBER
|| ntohs(tc->th_sport) == PPTP_CONTROL_PORT_NUMBER)
AliasHandlePptpOut(pip, link);
/* Adjust TCP checksum since source port is being aliased */
/* and source address is being altered */
accumulate = tc->th_sport;
tc->th_sport = alias_port;
accumulate -= tc->th_sport;
sptr = (u_short *) &(pip->ip_src);
accumulate += *sptr++;
accumulate += *sptr;
sptr = (u_short *) &alias_address;
accumulate -= *sptr++;
accumulate -= *sptr;
/* Modify sequence number if necessary */
if (GetAckModified(link) == 1)
{
int delta;
delta = GetDeltaSeqOut(pip, link);
if (delta != 0)
{
sptr = (u_short *) &tc->th_seq;
accumulate += *sptr++;
accumulate += *sptr;
tc->th_seq = htonl(ntohl(tc->th_seq) + delta);
sptr = (u_short *) &tc->th_seq;
accumulate -= *sptr++;
accumulate -= *sptr;
}
}
ADJUST_CHECKSUM(accumulate, tc->th_sum);
/* Change source address */
sptr = (u_short *) &(pip->ip_src);
accumulate = *sptr++;
accumulate += *sptr;
pip->ip_src = alias_address;
sptr = (u_short *) &(pip->ip_src);
accumulate -= *sptr++;
accumulate -= *sptr;
ADJUST_CHECKSUM(accumulate, pip->ip_sum);
return(PKT_ALIAS_OK);
}
return(PKT_ALIAS_IGNORED);
}
