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freebsd-nq/sbin/ipfw/ipfw.c
Julian Elischer 135a88d805 Allow ipfw to look up service names from /etc/services (or NIS if turned on) 
note.. this would be dangerous if your ipfw was blocking NIS access :)

Submitted by: archie@whistle.com (Archie Cobbs)
1997-06-23 22:32:13 +00:00

1203 lines
27 KiB
C
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/*
* Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
* Copyright (c) 1994 Ugen J.S.Antsilevich
*
* Idea and grammar partially left from:
* Copyright (c) 1993 Daniel Boulet
*
* Redistribution and use in source forms, with and without modification,
* are permitted provided that this entire comment appears intact.
*
* Redistribution in binary form may occur without any restrictions.
* Obviously, it would be nice if you gave credit where credit is due
* but requiring it would be too onerous.
*
* This software is provided ``AS IS'' without any warranties of any kind.
*
* NEW command line interface for IP firewall facility
*
* $Id: ipfw.c,v 1.44 1997/06/13 06:27:12 charnier Exp $
*
*/
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/time.h>
#include <ctype.h>
#include <err.h>
#include <limits.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip_var.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip_fw.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
int lineno = -1;
int s; /* main RAW socket */
int do_resolv=0; /* Would try to resolv all */
int do_acct=0; /* Show packet/byte count */
int do_time=0; /* Show time stamps */
int do_quiet=0; /* Be quiet in add and flush */
int do_force=0; /* Don't ask for confirmation */
struct icmpcode {
int code;
char *str;
};
static struct icmpcode icmpcodes[] = {
{ ICMP_UNREACH_NET, "net" },
{ ICMP_UNREACH_HOST, "host" },
{ ICMP_UNREACH_PROTOCOL, "protocol" },
{ ICMP_UNREACH_PORT, "port" },
{ ICMP_UNREACH_NEEDFRAG, "needfrag" },
{ ICMP_UNREACH_SRCFAIL, "srcfail" },
{ ICMP_UNREACH_NET_UNKNOWN, "net-unknown" },
{ ICMP_UNREACH_HOST_UNKNOWN, "host-unknown" },
{ ICMP_UNREACH_ISOLATED, "isolated" },
{ ICMP_UNREACH_NET_PROHIB, "net-prohib" },
{ ICMP_UNREACH_HOST_PROHIB, "host-prohib" },
{ ICMP_UNREACH_TOSNET, "tosnet" },
{ ICMP_UNREACH_TOSHOST, "toshost" },
{ ICMP_UNREACH_FILTER_PROHIB, "filter-prohib" },
{ ICMP_UNREACH_HOST_PRECEDENCE, "host-precedence" },
{ ICMP_UNREACH_PRECEDENCE_CUTOFF, "precedence-cutoff" },
{ 0, NULL }
};
static int
mask_bits(struct in_addr m_ad)
{
int h_fnd=0,h_num=0,i;
u_long mask;
mask=ntohl(m_ad.s_addr);
for (i=0;i<sizeof(u_long)*CHAR_BIT;i++) {
if (mask & 1L) {
h_fnd=1;
h_num++;
} else {
if (h_fnd)
return -1;
}
mask=mask>>1;
}
return h_num;
}
void
print_port(prot, port, comma)
u_char prot;
u_short port;
const char *comma;
{
struct servent *se;
struct protoent *pe;
const char *protocol;
int printed = 0;
if (do_resolv) {
pe = getprotobynumber(prot);
if (pe)
protocol = pe->p_name;
else
protocol = NULL;
se = getservbyport(htons(port), protocol);
if (se) {
printf("%s%s", comma, se->s_name);
printed = 1;
}
}
if (!printed)
printf("%s%d",comma,port);
}
static void
print_iface(char *key, union ip_fw_if *un, int byname)
{
char ifnb[FW_IFNLEN+1];
if (byname) {
strncpy(ifnb, un->fu_via_if.name, FW_IFNLEN);
ifnb[FW_IFNLEN]='\0';
if (un->fu_via_if.unit == -1)
printf(" %s %s*", key, ifnb);
else
printf(" %s %s%d", key, ifnb, un->fu_via_if.unit);
} else if (un->fu_via_ip.s_addr != 0) {
printf(" %s %s", key, inet_ntoa(un->fu_via_ip));
} else
printf(" %s any", key);
}
static void
print_reject_code(int code)
{
struct icmpcode *ic;
for (ic = icmpcodes; ic->str; ic++)
if (ic->code == code) {
printf("%s", ic->str);
return;
}
printf("%u", code);
}
static void
show_ipfw(struct ip_fw *chain)
{
char *comma;
u_long adrt;
struct hostent *he;
struct protoent *pe;
int i, mb;
int nsp = IP_FW_GETNSRCP(chain);
int ndp = IP_FW_GETNDSTP(chain);
if (do_resolv)
setservent(1/*stayopen*/);
printf("%05u ", chain->fw_number);
if (do_acct)
printf("%10lu %10lu ",chain->fw_pcnt,chain->fw_bcnt);
if (do_time)
{
if (chain->timestamp)
{
char timestr[30];
strcpy(timestr, ctime((time_t *)&chain->timestamp));
*strchr(timestr, '\n') = '\0';
printf("%s ", timestr);
}
else
printf(" ");
}
switch (chain->fw_flg & IP_FW_F_COMMAND)
{
case IP_FW_F_ACCEPT:
printf("allow");
break;
case IP_FW_F_DENY:
printf("deny");
break;
case IP_FW_F_COUNT:
printf("count");
break;
case IP_FW_F_DIVERT:
printf("divert %u", chain->fw_divert_port);
break;
case IP_FW_F_TEE:
printf("tee %u", chain->fw_divert_port);
break;
case IP_FW_F_SKIPTO:
printf("skipto %u", chain->fw_skipto_rule);
break;
case IP_FW_F_REJECT:
if (chain->fw_reject_code == IP_FW_REJECT_RST)
printf("reset");
else {
printf("unreach ");
print_reject_code(chain->fw_reject_code);
}
break;
default:
errx(1, "impossible");
}
if (chain->fw_flg & IP_FW_F_PRN)
printf(" log");
pe = getprotobynumber(chain->fw_prot);
if (pe)
printf(" %s", pe->p_name);
else
printf(" %u", chain->fw_prot);
printf(" from %s", chain->fw_flg & IP_FW_F_INVSRC ? "not " : "");
adrt=ntohl(chain->fw_smsk.s_addr);
if (adrt==ULONG_MAX && do_resolv) {
adrt=(chain->fw_src.s_addr);
he=gethostbyaddr((char *)&adrt,sizeof(u_long),AF_INET);
if (he==NULL) {
printf(inet_ntoa(chain->fw_src));
} else
printf("%s",he->h_name);
} else {
if (adrt!=ULONG_MAX) {
mb=mask_bits(chain->fw_smsk);
if (mb == 0) {
printf("any");
} else {
if (mb > 0) {
printf(inet_ntoa(chain->fw_src));
printf("/%d",mb);
} else {
printf(inet_ntoa(chain->fw_src));
printf(":");
printf(inet_ntoa(chain->fw_smsk));
}
}
} else
printf(inet_ntoa(chain->fw_src));
}
if (chain->fw_prot == IPPROTO_TCP || chain->fw_prot == IPPROTO_UDP) {
comma = " ";
for (i = 0; i < nsp; i++) {
print_port(chain->fw_prot, chain->fw_pts[i], comma);
if (i==0 && (chain->fw_flg & IP_FW_F_SRNG))
comma = "-";
else
comma = ",";
}
}
printf(" to %s", chain->fw_flg & IP_FW_F_INVDST ? "not " : "");
adrt=ntohl(chain->fw_dmsk.s_addr);
if (adrt==ULONG_MAX && do_resolv) {
adrt=(chain->fw_dst.s_addr);
he=gethostbyaddr((char *)&adrt,sizeof(u_long),AF_INET);
if (he==NULL) {
printf(inet_ntoa(chain->fw_dst));
} else
printf("%s",he->h_name);
} else {
if (adrt!=ULONG_MAX) {
mb=mask_bits(chain->fw_dmsk);
if (mb == 0) {
printf("any");
} else {
if (mb > 0) {
printf(inet_ntoa(chain->fw_dst));
printf("/%d",mb);
} else {
printf(inet_ntoa(chain->fw_dst));
printf(":");
printf(inet_ntoa(chain->fw_dmsk));
}
}
} else
printf(inet_ntoa(chain->fw_dst));
}
if (chain->fw_prot == IPPROTO_TCP || chain->fw_prot == IPPROTO_UDP) {
comma = " ";
for (i = 0; i < ndp; i++) {
print_port(chain->fw_prot, chain->fw_pts[nsp+i], comma);
if (i==0 && (chain->fw_flg & IP_FW_F_DRNG))
comma = "-";
else
comma = ",";
}
}
/* Direction */
if ((chain->fw_flg & IP_FW_F_IN) && !(chain->fw_flg & IP_FW_F_OUT))
printf(" in");
if (!(chain->fw_flg & IP_FW_F_IN) && (chain->fw_flg & IP_FW_F_OUT))
printf(" out");
/* Handle hack for "via" backwards compatibility */
if ((chain->fw_flg & IF_FW_F_VIAHACK) == IF_FW_F_VIAHACK) {
print_iface("via",
&chain->fw_in_if, chain->fw_flg & IP_FW_F_IIFNAME);
} else {
/* Receive interface specified */
if (chain->fw_flg & IP_FW_F_IIFACE)
print_iface("recv", &chain->fw_in_if,
chain->fw_flg & IP_FW_F_IIFNAME);
/* Transmit interface specified */
if (chain->fw_flg & IP_FW_F_OIFACE)
print_iface("xmit", &chain->fw_out_if,
chain->fw_flg & IP_FW_F_OIFNAME);
}
if (chain->fw_flg & IP_FW_F_FRAG)
printf(" frag");
if (chain->fw_ipopt || chain->fw_ipnopt) {
int _opt_printed = 0;
#define PRINTOPT(x) {if (_opt_printed) printf(",");\
printf(x); _opt_printed = 1;}
printf(" ipopt ");
if (chain->fw_ipopt & IP_FW_IPOPT_SSRR) PRINTOPT("ssrr");
if (chain->fw_ipnopt & IP_FW_IPOPT_SSRR) PRINTOPT("!ssrr");
if (chain->fw_ipopt & IP_FW_IPOPT_LSRR) PRINTOPT("lsrr");
if (chain->fw_ipnopt & IP_FW_IPOPT_LSRR) PRINTOPT("!lsrr");
if (chain->fw_ipopt & IP_FW_IPOPT_RR) PRINTOPT("rr");
if (chain->fw_ipnopt & IP_FW_IPOPT_RR) PRINTOPT("!rr");
if (chain->fw_ipopt & IP_FW_IPOPT_TS) PRINTOPT("ts");
if (chain->fw_ipnopt & IP_FW_IPOPT_TS) PRINTOPT("!ts");
}
if (chain->fw_tcpf & IP_FW_TCPF_ESTAB)
printf(" established");
else if (chain->fw_tcpf == IP_FW_TCPF_SYN &&
chain->fw_tcpnf == IP_FW_TCPF_ACK)
printf(" setup");
else if (chain->fw_tcpf || chain->fw_tcpnf) {
int _flg_printed = 0;
#define PRINTFLG(x) {if (_flg_printed) printf(",");\
printf(x); _flg_printed = 1;}
printf(" tcpflg ");
if (chain->fw_tcpf & IP_FW_TCPF_FIN) PRINTFLG("fin");
if (chain->fw_tcpnf & IP_FW_TCPF_FIN) PRINTFLG("!fin");
if (chain->fw_tcpf & IP_FW_TCPF_SYN) PRINTFLG("syn");
if (chain->fw_tcpnf & IP_FW_TCPF_SYN) PRINTFLG("!syn");
if (chain->fw_tcpf & IP_FW_TCPF_RST) PRINTFLG("rst");
if (chain->fw_tcpnf & IP_FW_TCPF_RST) PRINTFLG("!rst");
if (chain->fw_tcpf & IP_FW_TCPF_PSH) PRINTFLG("psh");
if (chain->fw_tcpnf & IP_FW_TCPF_PSH) PRINTFLG("!psh");
if (chain->fw_tcpf & IP_FW_TCPF_ACK) PRINTFLG("ack");
if (chain->fw_tcpnf & IP_FW_TCPF_ACK) PRINTFLG("!ack");
if (chain->fw_tcpf & IP_FW_TCPF_URG) PRINTFLG("urg");
if (chain->fw_tcpnf & IP_FW_TCPF_URG) PRINTFLG("!urg");
}
if (chain->fw_flg & IP_FW_F_ICMPBIT) {
int type_index;
int first = 1;
printf(" icmptype");
for (type_index = 0; type_index < 256; ++type_index)
if (chain->fw_icmptypes[type_index / (sizeof(unsigned) * 8)] &
(1U << (type_index % (sizeof(unsigned) * 8)))) {
printf("%c%d", first == 1 ? ' ' : ',', type_index);
first = 0;
}
}
printf("\n");
if (do_resolv)
endservent();
}
void
list(ac, av)
int ac;
char **av;
{
struct ip_fw *r;
struct ip_fw rules[1024];
int l,i;
memset(rules,0,sizeof rules);
l = sizeof rules;
i = getsockopt(s, IPPROTO_IP, IP_FW_GET, rules, &l);
if (i < 0)
err(2,"getsockopt(IP_FW_GET)");
for (r=rules; l >= sizeof rules[0]; r++, l-=sizeof rules[0])
show_ipfw(r);
}
static void
show_usage(const char *fmt, ...)
{
if (fmt) {
char buf[100];
va_list args;
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
warnx("error: %s", buf);
}
fprintf(stderr, "usage: ipfw [options]\n"
" flush\n"
" add [number] rule\n"
" delete number ...\n"
" list [number]\n"
" show [number]\n"
" zero [number ...]\n"
" rule: action proto src dst extras...\n"
" action:\n"
" {allow|permit|accept|pass|deny|drop|reject|unreach code|\n"
" reset|count|skipto num|divert port|tee port} [log]\n"
" proto: {ip|tcp|udp|icmp|<number>}\n"
" src: from [not] {any|ip[{/bits|:mask}]} [{port|port-port},[port],...]\n"
" dst: to [not] {any|ip[{/bits|:mask}]} [{port|port-port},[port],...]\n"
" extras:\n"
" fragment\n"
" in\n"
" out\n"
" {xmit|recv|via} {iface|ip|any}\n"
" {established|setup}\n"
" tcpflags [!]{syn|fin|rst|ack|psh|urg},...\n"
" ipoptions [!]{ssrr|lsrr|rr|ts},...\n"
" icmptypes {type[,type]}...\n");
exit(1);
}
static int
lookup_host (host, ipaddr)
char *host;
struct in_addr *ipaddr;
{
struct hostent *he = gethostbyname(host);
if (!he)
return(-1);
*ipaddr = *(struct in_addr *)he->h_addr_list[0];
return(0);
}
void
fill_ip(ipno, mask, acp, avp)
struct in_addr *ipno, *mask;
int *acp;
char ***avp;
{
int ac = *acp;
char **av = *avp;
char *p = 0, md = 0;
if (ac && !strncmp(*av,"any",strlen(*av))) {
ipno->s_addr = mask->s_addr = 0; av++; ac--;
} else {
p = strchr(*av, '/');
if (!p)
p = strchr(*av, ':');
if (p) {
md = *p;
*p++ = '\0';
}
if (lookup_host(*av, ipno) != 0)
show_usage("hostname ``%s'' unknown", *av);
switch (md) {
case ':':
if (!inet_aton(p,mask))
show_usage("bad netmask ``%s''", p);
break;
case '/':
if (atoi(p) == 0) {
mask->s_addr = 0;
} else if (atoi(p) > 32) {
show_usage("bad width ``%s''", p);
} else {
mask->s_addr =
htonl(~0 << (32 - atoi(p)));
}
break;
default:
mask->s_addr = htonl(~0);
break;
}
ipno->s_addr &= mask->s_addr;
av++;
ac--;
}
*acp = ac;
*avp = av;
}
static void
fill_reject_code(u_short *codep, char *str)
{
struct icmpcode *ic;
u_long val;
char *s;
val = strtoul(str, &s, 0);
if (s != str && *s == '\0' && val < 0x100) {
*codep = val;
return;
}
for (ic = icmpcodes; ic->str; ic++)
if (!strcasecmp(str, ic->str)) {
*codep = ic->code;
return;
}
show_usage("unknown ICMP unreachable code ``%s''", str);
}
static void
add_port(cnt, ptr, off, port)
u_short *cnt, *ptr, off, port;
{
if (off + *cnt >= IP_FW_MAX_PORTS)
errx(1, "too many ports (max is %d)", IP_FW_MAX_PORTS);
ptr[off+*cnt] = port;
(*cnt)++;
}
static int
lookup_port(const char *arg, int test, int nodash)
{
int val;
char *earg, buf[32];
struct servent *s;
snprintf(buf, sizeof(buf), "%s", arg);
buf[strcspn(arg, nodash ? "-," : ",")] = 0;
val = (int) strtoul(buf, &earg, 0);
if (!*buf || *earg) {
setservent(1);
if ((s = getservbyname(buf, NULL))) {
val = htons(s->s_port);
} else {
if (!test) {
errx(1, "unknown port ``%s''", arg);
}
val = -1;
}
} else {
if (val < 0 || val > 0xffff) {
if (!test) {
errx(1, "port ``%s'' out of range", arg);
}
val = -1;
}
}
return(val);
}
int
fill_port(cnt, ptr, off, arg)
u_short *cnt, *ptr, off;
char *arg;
{
char *s;
int initial_range = 0;
s = arg + strcspn(arg, "-,"); /* first port name can't have a dash */
if (*s == '-') {
*s++ = '\0';
if (strchr(arg, ','))
errx(1, "port range must be first in list");
add_port(cnt, ptr, off, *arg ? lookup_port(arg, 0, 0) : 0x0000);
arg = s;
s = strchr(arg,',');
if (s)
*s++ = '\0';
add_port(cnt, ptr, off, *arg ? lookup_port(arg, 0, 0) : 0xffff);
arg = s;
initial_range = 1;
}
while (arg != NULL) {
s = strchr(arg,',');
if (s)
*s++ = '\0';
add_port(cnt, ptr, off, lookup_port(arg, 0, 0));
arg = s;
}
return initial_range;
}
void
fill_tcpflag(set, reset, vp)
u_char *set, *reset;
char **vp;
{
char *p = *vp,*q;
u_char *d;
while (p && *p) {
struct tpcflags {
char * name;
u_char value;
} flags[] = {
{ "syn", IP_FW_TCPF_SYN },
{ "fin", IP_FW_TCPF_FIN },
{ "ack", IP_FW_TCPF_ACK },
{ "psh", IP_FW_TCPF_PSH },
{ "rst", IP_FW_TCPF_RST },
{ "urg", IP_FW_TCPF_URG }
};
int i;
if (*p == '!') {
p++;
d = reset;
} else {
d = set;
}
q = strchr(p, ',');
if (q)
*q++ = '\0';
for (i = 0; i < sizeof(flags) / sizeof(flags[0]); ++i)
if (!strncmp(p, flags[i].name, strlen(p))) {
*d |= flags[i].value;
break;
}
if (i == sizeof(flags) / sizeof(flags[0]))
show_usage("invalid tcp flag ``%s''", p);
p = q;
}
}
static void
fill_ipopt(u_char *set, u_char *reset, char **vp)
{
char *p = *vp,*q;
u_char *d;
while (p && *p) {
if (*p == '!') {
p++;
d = reset;
} else {
d = set;
}
q = strchr(p, ',');
if (q)
*q++ = '\0';
if (!strncmp(p,"ssrr",strlen(p))) *d |= IP_FW_IPOPT_SSRR;
if (!strncmp(p,"lsrr",strlen(p))) *d |= IP_FW_IPOPT_LSRR;
if (!strncmp(p,"rr",strlen(p))) *d |= IP_FW_IPOPT_RR;
if (!strncmp(p,"ts",strlen(p))) *d |= IP_FW_IPOPT_TS;
p = q;
}
}
void
fill_icmptypes(types, vp, fw_flg)
u_long *types;
char **vp;
u_short *fw_flg;
{
char *c = *vp;
while (*c)
{
unsigned long icmptype;
if ( *c == ',' )
++c;
icmptype = strtoul(c, &c, 0);
if ( *c != ',' && *c != '\0' )
show_usage("invalid ICMP type");
if (icmptype > 255)
show_usage("ICMP types are between 0 and 255 inclusive");
types[icmptype / (sizeof(unsigned) * 8)] |=
1 << (icmptype % (sizeof(unsigned) * 8));
*fw_flg |= IP_FW_F_ICMPBIT;
}
}
void
delete(ac,av)
int ac;
char **av;
{
struct ip_fw rule;
int i;
memset(&rule, 0, sizeof rule);
av++; ac--;
/* Rule number */
while (ac && isdigit(**av)) {
rule.fw_number = atoi(*av); av++; ac--;
i = setsockopt(s, IPPROTO_IP, IP_FW_DEL, &rule, sizeof rule);
if (i)
warn("setsockopt(%s)", "IP_FW_DEL");
}
}
static void
verify_interface(union ip_fw_if *ifu)
{
struct ifreq ifr;
/*
* If a unit was specified, check for that exact interface.
* If a wildcard was specified, check for unit 0.
*/
snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d",
ifu->fu_via_if.name,
ifu->fu_via_if.unit == -1 ? 0 : ifu->fu_via_if.unit);
if (ioctl(s, SIOCGIFFLAGS, &ifr) < 0)
warnx("warning: interface ``%s'' does not exist", ifr.ifr_name);
}
static void
fill_iface(char *which, union ip_fw_if *ifu, int *byname, int ac, char *arg)
{
if (!ac)
show_usage("missing argument for ``%s''", which);
/* Parse the interface or address */
if (!strcmp(arg, "any")) {
ifu->fu_via_ip.s_addr = 0;
*byname = 0;
} else if (!isdigit(*arg)) {
char *q;
*byname = 1;
strncpy(ifu->fu_via_if.name, arg, sizeof(ifu->fu_via_if.name));
ifu->fu_via_if.name[sizeof(ifu->fu_via_if.name) - 1] = '\0';
for (q = ifu->fu_via_if.name;
*q && !isdigit(*q) && *q != '*'; q++)
continue;
ifu->fu_via_if.unit = (*q == '*') ? -1 : atoi(q);
*q = '\0';
verify_interface(ifu);
} else if (!inet_aton(arg, &ifu->fu_via_ip)) {
show_usage("bad ip address ``%s''", arg);
} else
*byname = 0;
}
static void
add(ac,av)
int ac;
char **av;
{
struct ip_fw rule;
int i;
u_char proto;
struct protoent *pe;
int saw_xmrc = 0, saw_via = 0;
memset(&rule, 0, sizeof rule);
av++; ac--;
/* Rule number */
if (ac && isdigit(**av)) {
rule.fw_number = atoi(*av); av++; ac--;
}
/* Action */
if (ac == 0)
show_usage("missing action");
if (!strncmp(*av,"accept",strlen(*av))
|| !strncmp(*av,"pass",strlen(*av))
|| !strncmp(*av,"allow",strlen(*av))
|| !strncmp(*av,"permit",strlen(*av))) {
rule.fw_flg |= IP_FW_F_ACCEPT; av++; ac--;
} else if (!strncmp(*av,"count",strlen(*av))) {
rule.fw_flg |= IP_FW_F_COUNT; av++; ac--;
} else if (!strncmp(*av,"divert",strlen(*av))) {
rule.fw_flg |= IP_FW_F_DIVERT; av++; ac--;
if (!ac)
show_usage("missing divert port");
rule.fw_divert_port = strtoul(*av, NULL, 0); av++; ac--;
if (rule.fw_divert_port == 0)
show_usage("illegal divert port");
} else if (!strncmp(*av,"tee",strlen(*av))) {
rule.fw_flg |= IP_FW_F_TEE; av++; ac--;
if (!ac)
show_usage("missing divert port");
rule.fw_divert_port = strtoul(*av, NULL, 0); av++; ac--;
if (rule.fw_divert_port == 0)
show_usage("illegal divert port");
} else if (!strncmp(*av,"skipto",strlen(*av))) {
rule.fw_flg |= IP_FW_F_SKIPTO; av++; ac--;
if (!ac)
show_usage("missing skipto rule number");
rule.fw_skipto_rule = strtoul(*av, NULL, 0); av++; ac--;
} else if ((!strncmp(*av,"deny",strlen(*av))
|| !strncmp(*av,"drop",strlen(*av)))) {
rule.fw_flg |= IP_FW_F_DENY; av++; ac--;
} else if (!strncmp(*av,"reject",strlen(*av))) {
rule.fw_flg |= IP_FW_F_REJECT; av++; ac--;
rule.fw_reject_code = ICMP_UNREACH_HOST;
} else if (!strncmp(*av,"reset",strlen(*av))) {
rule.fw_flg |= IP_FW_F_REJECT; av++; ac--;
rule.fw_reject_code = IP_FW_REJECT_RST; /* check TCP later */
} else if (!strncmp(*av,"unreach",strlen(*av))) {
rule.fw_flg |= IP_FW_F_REJECT; av++; ac--;
fill_reject_code(&rule.fw_reject_code, *av); av++; ac--;
} else {
show_usage("invalid action ``%s''", *av);
}
/* [log] */
if (ac && !strncmp(*av,"log",strlen(*av))) {
rule.fw_flg |= IP_FW_F_PRN; av++; ac--;
}
/* protocol */
if (ac == 0)
show_usage("missing protocol");
if ((proto = atoi(*av)) > 0) {
rule.fw_prot = proto; av++; ac--;
} else if (!strncmp(*av,"all",strlen(*av))) {
rule.fw_prot = IPPROTO_IP; av++; ac--;
} else if ((pe = getprotobyname(*av)) != NULL) {
rule.fw_prot = pe->p_proto; av++; ac--;
} else {
show_usage("invalid protocol ``%s''", *av);
}
if (rule.fw_prot != IPPROTO_TCP
&& (rule.fw_flg & IP_FW_F_COMMAND) == IP_FW_F_REJECT
&& rule.fw_reject_code == IP_FW_REJECT_RST)
show_usage("``reset'' is only valid for tcp packets");
/* from */
if (ac && !strncmp(*av,"from",strlen(*av))) { av++; ac--; }
else
show_usage("missing ``from''");
if (ac && !strncmp(*av,"not",strlen(*av))) {
rule.fw_flg |= IP_FW_F_INVSRC;
av++; ac--;
}
if (!ac)
show_usage("missing arguments");
fill_ip(&rule.fw_src, &rule.fw_smsk, &ac, &av);
if (ac && (isdigit(**av) || lookup_port(*av, 1, 1) >= 0)) {
u_short nports = 0;
if (fill_port(&nports, rule.fw_pts, 0, *av))
rule.fw_flg |= IP_FW_F_SRNG;
IP_FW_SETNSRCP(&rule, nports);
av++; ac--;
}
/* to */
if (ac && !strncmp(*av,"to",strlen(*av))) { av++; ac--; }
else
show_usage("missing ``to''");
if (ac && !strncmp(*av,"not",strlen(*av))) {
rule.fw_flg |= IP_FW_F_INVDST;
av++; ac--;
}
if (!ac)
show_usage("missing arguments");
fill_ip(&rule.fw_dst, &rule.fw_dmsk, &ac, &av);
if (ac && (isdigit(**av) || lookup_port(*av, 1, 1) >= 0)) {
u_short nports = 0;
if (fill_port(&nports,
rule.fw_pts, IP_FW_GETNSRCP(&rule), *av))
rule.fw_flg |= IP_FW_F_DRNG;
IP_FW_SETNDSTP(&rule, nports);
av++; ac--;
}
if ((rule.fw_prot != IPPROTO_TCP) && (rule.fw_prot != IPPROTO_UDP)
&& (IP_FW_GETNSRCP(&rule) || IP_FW_GETNDSTP(&rule))) {
show_usage("only TCP and UDP protocols are valid"
" with port specifications");
}
while (ac) {
if (!strncmp(*av,"in",strlen(*av))) {
rule.fw_flg |= IP_FW_F_IN;
av++; ac--; continue;
}
if (!strncmp(*av,"out",strlen(*av))) {
rule.fw_flg |= IP_FW_F_OUT;
av++; ac--; continue;
}
if (ac && !strncmp(*av,"xmit",strlen(*av))) {
union ip_fw_if ifu;
int byname;
if (saw_via) {
badviacombo:
show_usage("``via'' is incompatible"
" with ``xmit'' and ``recv''");
}
saw_xmrc = 1;
av++; ac--;
fill_iface("xmit", &ifu, &byname, ac, *av);
rule.fw_out_if = ifu;
rule.fw_flg |= IP_FW_F_OIFACE;
if (byname)
rule.fw_flg |= IP_FW_F_OIFNAME;
av++; ac--; continue;
}
if (ac && !strncmp(*av,"recv",strlen(*av))) {
union ip_fw_if ifu;
int byname;
if (saw_via)
goto badviacombo;
saw_xmrc = 1;
av++; ac--;
fill_iface("recv", &ifu, &byname, ac, *av);
rule.fw_in_if = ifu;
rule.fw_flg |= IP_FW_F_IIFACE;
if (byname)
rule.fw_flg |= IP_FW_F_IIFNAME;
av++; ac--; continue;
}
if (ac && !strncmp(*av,"via",strlen(*av))) {
union ip_fw_if ifu;
int byname = 0;
if (saw_xmrc)
goto badviacombo;
saw_via = 1;
av++; ac--;
fill_iface("via", &ifu, &byname, ac, *av);
rule.fw_out_if = rule.fw_in_if = ifu;
if (byname)
rule.fw_flg |=
(IP_FW_F_IIFNAME | IP_FW_F_OIFNAME);
av++; ac--; continue;
}
if (!strncmp(*av,"fragment",strlen(*av))) {
rule.fw_flg |= IP_FW_F_FRAG;
av++; ac--; continue;
}
if (!strncmp(*av,"ipoptions",strlen(*av))) {
av++; ac--;
if (!ac)
show_usage("missing argument"
" for ``ipoptions''");
fill_ipopt(&rule.fw_ipopt, &rule.fw_ipnopt, av);
av++; ac--; continue;
}
if (rule.fw_prot == IPPROTO_TCP) {
if (!strncmp(*av,"established",strlen(*av))) {
rule.fw_tcpf |= IP_FW_TCPF_ESTAB;
av++; ac--; continue;
}
if (!strncmp(*av,"setup",strlen(*av))) {
rule.fw_tcpf |= IP_FW_TCPF_SYN;
rule.fw_tcpnf |= IP_FW_TCPF_ACK;
av++; ac--; continue;
}
if (!strncmp(*av,"tcpflags",strlen(*av))) {
av++; ac--;
if (!ac)
show_usage("missing argument"
" for ``tcpflags''");
fill_tcpflag(&rule.fw_tcpf, &rule.fw_tcpnf, av);
av++; ac--; continue;
}
}
if (rule.fw_prot == IPPROTO_ICMP) {
if (!strncmp(*av,"icmptypes",strlen(*av))) {
av++; ac--;
if (!ac)
show_usage("missing argument"
" for ``icmptypes''");
fill_icmptypes(rule.fw_icmptypes,
av, &rule.fw_flg);
av++; ac--; continue;
}
}
show_usage("unknown argument ``%s''", *av);
}
/* No direction specified -> do both directions */
if (!(rule.fw_flg & (IP_FW_F_OUT|IP_FW_F_IN)))
rule.fw_flg |= (IP_FW_F_OUT|IP_FW_F_IN);
/* Sanity check interface check, but handle "via" case separately */
if (saw_via) {
if (rule.fw_flg & IP_FW_F_IN)
rule.fw_flg |= IP_FW_F_IIFACE;
if (rule.fw_flg & IP_FW_F_OUT)
rule.fw_flg |= IP_FW_F_OIFACE;
} else if ((rule.fw_flg & IP_FW_F_OIFACE) && (rule.fw_flg & IP_FW_F_IN))
show_usage("can't check xmit interface of incoming packets");
if (!do_quiet)
show_ipfw(&rule);
i = setsockopt(s, IPPROTO_IP, IP_FW_ADD, &rule, sizeof rule);
if (i)
err(1, "setsockopt(%s)", "IP_FW_ADD");
}
static void
zero (ac, av)
int ac;
char **av;
{
av++; ac--;
if (!ac) {
/* clear all entries */
if (setsockopt(s,IPPROTO_IP,IP_FW_ZERO,NULL,0)<0)
err(1, "setsockopt(%s)", "IP_FW_ZERO");
if (!do_quiet)
printf("Accounting cleared.\n");
} else {
struct ip_fw rule;
memset(&rule, 0, sizeof rule);
while (ac) {
/* Rule number */
if (isdigit(**av)) {
rule.fw_number = atoi(*av); av++; ac--;
if (setsockopt(s, IPPROTO_IP,
IP_FW_ZERO, &rule, sizeof rule))
warn("setsockopt(%s)", "IP_FW_ZERO");
else
printf("Entry %d cleared\n",
rule.fw_number);
} else
show_usage("invalid rule number ``%s''", *av);
}
}
}
int
ipfw_main(ac,av)
int ac;
char **av;
{
char ch;
extern int optind;
if ( ac == 1 ) {
show_usage(NULL);
}
/* Set the force flag for non-interactive processes */
do_force = !isatty(STDIN_FILENO);
while ((ch = getopt(ac, av ,"afqtN")) != -1)
switch(ch) {
case 'a':
do_acct=1;
break;
case 'f':
do_force=1;
break;
case 'q':
do_quiet=1;
break;
case 't':
do_time=1;
break;
case 'N':
do_resolv=1;
break;
default:
show_usage(NULL);
}
ac -= optind;
if (*(av+=optind)==NULL) {
show_usage("Bad arguments");
}
if (!strncmp(*av, "add", strlen(*av))) {
add(ac,av);
} else if (!strncmp(*av, "delete", strlen(*av))) {
delete(ac,av);
} else if (!strncmp(*av, "flush", strlen(*av))) {
int do_flush = 0;
if ( do_force || do_quiet )
do_flush = 1;
else {
int c;
/* Ask the user */
printf("Are you sure? [yn] ");
do {
fflush(stdout);
c = toupper(getc(stdin));
while (c != '\n' && getc(stdin) != '\n')
if (feof(stdin))
return (0);
} while (c != 'Y' && c != 'N');
printf("\n");
if (c == 'Y')
do_flush = 1;
}
if ( do_flush ) {
if (setsockopt(s,IPPROTO_IP,IP_FW_FLUSH,NULL,0) < 0)
err(1, "setsockopt(%s)", "IP_FW_FLUSH");
if (!do_quiet)
printf("Flushed all rules.\n");
}
} else if (!strncmp(*av, "zero", strlen(*av))) {
zero(ac,av);
} else if (!strncmp(*av, "print", strlen(*av))) {
list(--ac,++av);
} else if (!strncmp(*av, "list", strlen(*av))) {
list(--ac,++av);
} else if (!strncmp(*av, "show", strlen(*av))) {
do_acct++;
list(--ac,++av);
} else {
show_usage("Bad arguments");
}
return 0;
}
int
main(ac, av)
int ac;
char **av;
{
#define MAX_ARGS 32
#define WHITESP " \t\f\v\n\r"
char buf[BUFSIZ];
char *a, *args[MAX_ARGS];
char linename[10];
int i;
FILE *f;
s = socket( AF_INET, SOCK_RAW, IPPROTO_RAW );
if ( s < 0 )
err(1, "socket");
setbuf(stdout,0);
if (av[1] && !access(av[1], R_OK)) {
lineno = 0;
if ((f = fopen(av[1], "r")) == NULL)
err(1, "fopen: %s", av[1]);
while (fgets(buf, BUFSIZ, f)) {
lineno++;
sprintf(linename, "Line %d", lineno);
args[0] = linename;
for (i = 1, a = strtok(buf, WHITESP);
a && i < MAX_ARGS; a = strtok(NULL, WHITESP), i++)
args[i] = a;
if (i == MAX_ARGS)
errx(1, "%s: too many arguments", linename);
args[i] = NULL;
ipfw_main(i, args);
}
fclose(f);
} else
ipfw_main(ac,av);
return 0;
}
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