blob: 413f178db4883d07abeb6f116fbe7b5dba7beb65 [file] [log] [blame]
/* Shared library add-on to iptables to add multiple TCP port support. */
#include <stdio.h>
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include <getopt.h>
#include <xtables.h>
#include <libiptc/libiptc.h>
#include <libiptc/libip6tc.h>
/* To ensure that iptables compiles with an old kernel */
#include "../include/linux/netfilter/xt_multiport.h"
/* Function which prints out usage message. */
static void multiport_help(void)
{
printf(
"multiport match options:\n"
" --source-ports port[,port,port...]\n"
" --sports ...\n"
" match source port(s)\n"
" --destination-ports port[,port,port...]\n"
" --dports ...\n"
" match destination port(s)\n"
" --ports port[,port,port]\n"
" match both source and destination port(s)\n"
" NOTE: this kernel does not support port ranges in multiport.\n");
}
static void multiport_help_v1(void)
{
printf(
"multiport match options:\n"
" --source-ports [!] port[,port:port,port...]\n"
" --sports ...\n"
" match source port(s)\n"
" --destination-ports [!] port[,port:port,port...]\n"
" --dports ...\n"
" match destination port(s)\n"
" --ports [!] port[,port:port,port]\n"
" match both source and destination port(s)\n");
}
static const struct option multiport_opts[] = {
{ "source-ports", 1, NULL, '1' },
{ "sports", 1, NULL, '1' }, /* synonym */
{ "destination-ports", 1, NULL, '2' },
{ "dports", 1, NULL, '2' }, /* synonym */
{ "ports", 1, NULL, '3' },
{ .name = NULL }
};
static char *
proto_to_name(u_int8_t proto)
{
switch (proto) {
case IPPROTO_TCP:
return "tcp";
case IPPROTO_UDP:
return "udp";
case IPPROTO_UDPLITE:
return "udplite";
case IPPROTO_SCTP:
return "sctp";
case IPPROTO_DCCP:
return "dccp";
default:
return NULL;
}
}
static unsigned int
parse_multi_ports(const char *portstring, u_int16_t *ports, const char *proto)
{
char *buffer, *cp, *next;
unsigned int i;
buffer = strdup(portstring);
if (!buffer) exit_error(OTHER_PROBLEM, "strdup failed");
for (cp=buffer, i=0; cp && i<XT_MULTI_PORTS; cp=next,i++)
{
next=strchr(cp, ',');
if (next) *next++='\0';
ports[i] = parse_port(cp, proto);
}
if (cp) exit_error(PARAMETER_PROBLEM, "too many ports specified");
free(buffer);
return i;
}
static void
parse_multi_ports_v1(const char *portstring,
struct xt_multiport_v1 *multiinfo,
const char *proto)
{
char *buffer, *cp, *next, *range;
unsigned int i;
u_int16_t m;
buffer = strdup(portstring);
if (!buffer) exit_error(OTHER_PROBLEM, "strdup failed");
for (i=0; i<XT_MULTI_PORTS; i++)
multiinfo->pflags[i] = 0;
for (cp=buffer, i=0; cp && i<XT_MULTI_PORTS; cp=next, i++) {
next=strchr(cp, ',');
if (next) *next++='\0';
range = strchr(cp, ':');
if (range) {
if (i == XT_MULTI_PORTS-1)
exit_error(PARAMETER_PROBLEM,
"too many ports specified");
*range++ = '\0';
}
multiinfo->ports[i] = parse_port(cp, proto);
if (range) {
multiinfo->pflags[i] = 1;
multiinfo->ports[++i] = parse_port(range, proto);
if (multiinfo->ports[i-1] >= multiinfo->ports[i])
exit_error(PARAMETER_PROBLEM,
"invalid portrange specified");
m <<= 1;
}
}
multiinfo->count = i;
if (cp) exit_error(PARAMETER_PROBLEM, "too many ports specified");
free(buffer);
}
static const char *
check_proto(u_int16_t pnum, u_int8_t invflags)
{
char *proto;
if (invflags & XT_INV_PROTO)
exit_error(PARAMETER_PROBLEM,
"multiport only works with TCP, UDP, UDPLITE, SCTP and DCCP");
if ((proto = proto_to_name(pnum)) != NULL)
return proto;
else if (!pnum)
exit_error(PARAMETER_PROBLEM,
"multiport needs `-p tcp', `-p udp', `-p udplite', "
"`-p sctp' or `-p dccp'");
else
exit_error(PARAMETER_PROBLEM,
"multiport only works with TCP, UDP, UDPLITE, SCTP and DCCP");
}
/* Function which parses command options; returns true if it
ate an option */
static int
__multiport_parse(int c, char **argv, int invert, unsigned int *flags,
struct xt_entry_match **match, u_int16_t pnum,
u_int8_t invflags)
{
const char *proto;
struct xt_multiport *multiinfo
= (struct xt_multiport *)(*match)->data;
switch (c) {
case '1':
check_inverse(argv[optind-1], &invert, &optind, 0);
proto = check_proto(pnum, invflags);
multiinfo->count = parse_multi_ports(argv[optind-1],
multiinfo->ports, proto);
multiinfo->flags = XT_MULTIPORT_SOURCE;
break;
case '2':
check_inverse(argv[optind-1], &invert, &optind, 0);
proto = check_proto(pnum, invflags);
multiinfo->count = parse_multi_ports(argv[optind-1],
multiinfo->ports, proto);
multiinfo->flags = XT_MULTIPORT_DESTINATION;
break;
case '3':
check_inverse(argv[optind-1], &invert, &optind, 0);
proto = check_proto(pnum, invflags);
multiinfo->count = parse_multi_ports(argv[optind-1],
multiinfo->ports, proto);
multiinfo->flags = XT_MULTIPORT_EITHER;
break;
default:
return 0;
}
if (invert)
exit_error(PARAMETER_PROBLEM,
"multiport does not support invert");
if (*flags)
exit_error(PARAMETER_PROBLEM,
"multiport can only have one option");
*flags = 1;
return 1;
}
static int
multiport_parse(int c, char **argv, int invert, unsigned int *flags,
const void *e, struct xt_entry_match **match)
{
const struct ipt_entry *entry = e;
return __multiport_parse(c, argv, invert, flags, match,
entry->ip.proto, entry->ip.invflags);
}
static int
multiport_parse6(int c, char **argv, int invert, unsigned int *flags,
const void *e, struct xt_entry_match **match)
{
const struct ip6t_entry *entry = (const struct ip6t_entry *)e;
return __multiport_parse(c, argv, invert, flags, match,
entry->ipv6.proto, entry->ipv6.invflags);
}
static int
__multiport_parse_v1(int c, char **argv, int invert, unsigned int *flags,
struct xt_entry_match **match, u_int16_t pnum,
u_int8_t invflags)
{
const char *proto;
struct xt_multiport_v1 *multiinfo
= (struct xt_multiport_v1 *)(*match)->data;
switch (c) {
case '1':
check_inverse(argv[optind-1], &invert, &optind, 0);
proto = check_proto(pnum, invflags);
parse_multi_ports_v1(argv[optind-1], multiinfo, proto);
multiinfo->flags = XT_MULTIPORT_SOURCE;
break;
case '2':
check_inverse(argv[optind-1], &invert, &optind, 0);
proto = check_proto(pnum, invflags);
parse_multi_ports_v1(argv[optind-1], multiinfo, proto);
multiinfo->flags = XT_MULTIPORT_DESTINATION;
break;
case '3':
check_inverse(argv[optind-1], &invert, &optind, 0);
proto = check_proto(pnum, invflags);
parse_multi_ports_v1(argv[optind-1], multiinfo, proto);
multiinfo->flags = XT_MULTIPORT_EITHER;
break;
default:
return 0;
}
if (invert)
multiinfo->invert = 1;
if (*flags)
exit_error(PARAMETER_PROBLEM,
"multiport can only have one option");
*flags = 1;
return 1;
}
static int
multiport_parse_v1(int c, char **argv, int invert, unsigned int *flags,
const void *e, struct xt_entry_match **match)
{
const struct ipt_entry *entry = e;
return __multiport_parse_v1(c, argv, invert, flags, match,
entry->ip.proto, entry->ip.invflags);
}
static int
multiport_parse6_v1(int c, char **argv, int invert, unsigned int *flags,
const void *e, struct xt_entry_match **match)
{
const struct ip6t_entry *entry = (const struct ip6t_entry *)e;
return __multiport_parse_v1(c, argv, invert, flags, match,
entry->ipv6.proto, entry->ipv6.invflags);
}
/* Final check; must specify something. */
static void multiport_check(unsigned int flags)
{
if (!flags)
exit_error(PARAMETER_PROBLEM, "multiport expection an option");
}
static char *
port_to_service(int port, u_int8_t proto)
{
struct servent *service;
if ((service = getservbyport(htons(port), proto_to_name(proto))))
return service->s_name;
return NULL;
}
static void
print_port(u_int16_t port, u_int8_t protocol, int numeric)
{
char *service;
if (numeric || (service = port_to_service(port, protocol)) == NULL)
printf("%u", port);
else
printf("%s", service);
}
/* Prints out the matchinfo. */
static void
__multiport_print(const struct xt_entry_match *match, int numeric,
u_int16_t proto)
{
const struct xt_multiport *multiinfo
= (const struct xt_multiport *)match->data;
unsigned int i;
printf("multiport ");
switch (multiinfo->flags) {
case XT_MULTIPORT_SOURCE:
printf("sports ");
break;
case XT_MULTIPORT_DESTINATION:
printf("dports ");
break;
case XT_MULTIPORT_EITHER:
printf("ports ");
break;
default:
printf("ERROR ");
break;
}
for (i=0; i < multiinfo->count; i++) {
printf("%s", i ? "," : "");
print_port(multiinfo->ports[i], proto, numeric);
}
printf(" ");
}
static void multiport_print(const void *ip_void,
const struct xt_entry_match *match, int numeric)
{
const struct ipt_ip *ip = ip_void;
__multiport_print(match, numeric, ip->proto);
}
static void multiport_print6(const void *ip_void,
const struct xt_entry_match *match, int numeric)
{
const struct ip6t_ip6 *ip = (const struct ip6t_ip6 *)ip_void;
__multiport_print(match, numeric, ip->proto);
}
static void __multiport_print_v1(const struct xt_entry_match *match,
int numeric, u_int16_t proto)
{
const struct xt_multiport_v1 *multiinfo
= (const struct xt_multiport_v1 *)match->data;
unsigned int i;
printf("multiport ");
switch (multiinfo->flags) {
case XT_MULTIPORT_SOURCE:
printf("sports ");
break;
case XT_MULTIPORT_DESTINATION:
printf("dports ");
break;
case XT_MULTIPORT_EITHER:
printf("ports ");
break;
default:
printf("ERROR ");
break;
}
if (multiinfo->invert)
printf("! ");
for (i=0; i < multiinfo->count; i++) {
printf("%s", i ? "," : "");
print_port(multiinfo->ports[i], proto, numeric);
if (multiinfo->pflags[i]) {
printf(":");
print_port(multiinfo->ports[++i], proto, numeric);
}
}
printf(" ");
}
static void multiport_print_v1(const void *ip_void,
const struct xt_entry_match *match, int numeric)
{
const struct ipt_ip *ip = ip_void;
__multiport_print_v1(match, numeric, ip->proto);
}
static void multiport_print6_v1(const void *ip_void,
const struct xt_entry_match *match, int numeric)
{
const struct ip6t_ip6 *ip = (const struct ip6t_ip6 *)ip_void;
__multiport_print_v1(match, numeric, ip->proto);
}
/* Saves the union ipt_matchinfo in parsable form to stdout. */
static void __multiport_save(const struct xt_entry_match *match,
u_int16_t proto)
{
const struct xt_multiport *multiinfo
= (const struct xt_multiport *)match->data;
unsigned int i;
switch (multiinfo->flags) {
case XT_MULTIPORT_SOURCE:
printf("--sports ");
break;
case XT_MULTIPORT_DESTINATION:
printf("--dports ");
break;
case XT_MULTIPORT_EITHER:
printf("--ports ");
break;
}
for (i=0; i < multiinfo->count; i++) {
printf("%s", i ? "," : "");
print_port(multiinfo->ports[i], proto, 1);
}
printf(" ");
}
static void multiport_save(const void *ip_void,
const struct xt_entry_match *match)
{
const struct ipt_ip *ip = ip_void;
__multiport_save(match, ip->proto);
}
static void multiport_save6(const void *ip_void,
const struct xt_entry_match *match)
{
const struct ip6t_ip6 *ip = (const struct ip6t_ip6 *)ip_void;
__multiport_save(match, ip->proto);
}
static void __multiport_save_v1(const struct xt_entry_match *match,
u_int16_t proto)
{
const struct xt_multiport_v1 *multiinfo
= (const struct xt_multiport_v1 *)match->data;
unsigned int i;
switch (multiinfo->flags) {
case XT_MULTIPORT_SOURCE:
printf("--sports ");
break;
case XT_MULTIPORT_DESTINATION:
printf("--dports ");
break;
case XT_MULTIPORT_EITHER:
printf("--ports ");
break;
}
if (multiinfo->invert)
printf("! ");
for (i=0; i < multiinfo->count; i++) {
printf("%s", i ? "," : "");
print_port(multiinfo->ports[i], proto, 1);
if (multiinfo->pflags[i]) {
printf(":");
print_port(multiinfo->ports[++i], proto, 1);
}
}
printf(" ");
}
static void multiport_save_v1(const void *ip_void,
const struct xt_entry_match *match)
{
const struct ipt_ip *ip = ip_void;
__multiport_save_v1(match, ip->proto);
}
static void multiport_save6_v1(const void *ip_void,
const struct xt_entry_match *match)
{
const struct ip6t_ip6 *ip = (const struct ip6t_ip6 *)ip_void;
__multiport_save_v1(match, ip->proto);
}
static struct xtables_match multiport_match = {
.family = AF_INET,
.name = "multiport",
.revision = 0,
.version = XTABLES_VERSION,
.size = XT_ALIGN(sizeof(struct xt_multiport)),
.userspacesize = XT_ALIGN(sizeof(struct xt_multiport)),
.help = multiport_help,
.parse = multiport_parse,
.final_check = multiport_check,
.print = multiport_print,
.save = multiport_save,
.extra_opts = multiport_opts,
};
static struct xtables_match multiport_match6 = {
.family = AF_INET6,
.name = "multiport",
.revision = 0,
.version = XTABLES_VERSION,
.size = XT_ALIGN(sizeof(struct xt_multiport)),
.userspacesize = XT_ALIGN(sizeof(struct xt_multiport)),
.help = multiport_help,
.parse = multiport_parse6,
.final_check = multiport_check,
.print = multiport_print6,
.save = multiport_save6,
.extra_opts = multiport_opts,
};
static struct xtables_match multiport_match_v1 = {
.family = AF_INET,
.name = "multiport",
.version = XTABLES_VERSION,
.revision = 1,
.size = XT_ALIGN(sizeof(struct xt_multiport_v1)),
.userspacesize = XT_ALIGN(sizeof(struct xt_multiport_v1)),
.help = multiport_help_v1,
.parse = multiport_parse_v1,
.final_check = multiport_check,
.print = multiport_print_v1,
.save = multiport_save_v1,
.extra_opts = multiport_opts,
};
static struct xtables_match multiport_match6_v1 = {
.family = AF_INET6,
.name = "multiport",
.version = XTABLES_VERSION,
.revision = 1,
.size = XT_ALIGN(sizeof(struct xt_multiport_v1)),
.userspacesize = XT_ALIGN(sizeof(struct xt_multiport_v1)),
.help = multiport_help_v1,
.parse = multiport_parse6_v1,
.final_check = multiport_check,
.print = multiport_print6_v1,
.save = multiport_save6_v1,
.extra_opts = multiport_opts,
};
void
_init(void)
{
xtables_register_match(&multiport_match);
xtables_register_match(&multiport_match6);
xtables_register_match(&multiport_match_v1);
xtables_register_match(&multiport_match6_v1);
}