NetBSD/dist/ipf/lib/getport.c

82 lines
1.7 KiB
C

/* $NetBSD: getport.c,v 1.6 2007/04/14 20:34:24 martin Exp $ */
/*
* Copyright (C) 2002-2005 by Darren Reed.
*
* See the IPFILTER.LICENCE file for details on licencing.
*
* Id: getport.c,v 1.1.4.6 2006/06/16 17:21:00 darrenr Exp
*/
#include "ipf.h"
int getport(fr, name, port)
frentry_t *fr;
char *name;
u_short *port;
{
struct protoent *p;
struct servent *s;
u_short p1;
if (fr == NULL || fr->fr_type != FR_T_IPF) {
s = getservbyname(name, NULL);
if (s != NULL) {
*port = s->s_port;
return 0;
}
return -1;
}
/*
* Some people will use port names in rules without specifying
* either TCP or UDP because it is implied by the group head.
* If we don't know the protocol, then the best we can do here is
* to take either only the TCP or UDP mapping (if one or the other
* is missing) or make sure both of them agree.
*/
if (fr->fr_proto == 0) {
s = getservbyname(name, "tcp");
if (s != NULL)
p1 = s->s_port;
else
p1 = 0;
s = getservbyname(name, "udp");
if (s != NULL) {
if (p1 != s->s_port)
return -1;
}
if ((p1 == 0) && (s == NULL))
return -1;
if (p1)
*port = p1;
else
*port = s->s_port;
return 0;
}
if ((fr->fr_flx & FI_TCPUDP) != 0) {
/*
* If a rule is "tcp/udp" then check that both TCP and UDP
* mappings for this protocol name match ports.
*/
s = getservbyname(name, "tcp");
if (s == NULL)
return -1;
p1 = s->s_port;
s = getservbyname(name, "udp");
if (s == NULL || s->s_port != p1)
return -1;
*port = p1;
return 0;
}
p = getprotobynumber(fr->fr_proto);
s = getservbyname(name, p ? p->p_name : NULL);
if (s != NULL) {
*port = s->s_port;
return 0;
}
return -1;
}