+++ /dev/null
-/* Shared library add-on to iptables to add redirect support. */
-#include <stdio.h>
-#include <netdb.h>
-#include <string.h>
-#include <stdlib.h>
-#include <getopt.h>
-#include <iptables.h>
-#include <linux/netfilter_ipv4/ip_tables.h>
-#include <linux/netfilter/nf_nat.h>
-
-#define IPT_REDIRECT_OPT_DEST 0x01
-#define IPT_REDIRECT_OPT_RANDOM 0x02
-
-/* Function which prints out usage message. */
-static void REDIRECT_help(void)
-{
- printf(
-"REDIRECT target options:\n"
-" --to-ports <port>[-<port>]\n"
-" Port (range) to map to.\n");
-}
-
-static const struct option REDIRECT_opts[] = {
- { "to-ports", 1, NULL, '1' },
- { "random", 0, NULL, '2' },
- { .name = NULL }
-};
-
-/* Initialize the target. */
-static void REDIRECT_init(struct xt_entry_target *t)
-{
- struct ip_nat_multi_range *mr = (struct ip_nat_multi_range *)t->data;
-
- /* Actually, it's 0, but it's ignored at the moment. */
- mr->rangesize = 1;
-
-}
-
-/* Parses ports */
-static void
-parse_ports(const char *arg, struct ip_nat_multi_range *mr)
-{
- const char *dash;
- int port;
-
- mr->range[0].flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
-
- if (strchr(arg, '.'))
- exit_error(PARAMETER_PROBLEM, "IP address not permitted\n");
-
- port = atoi(arg);
- if (port == 0)
- port = service_to_port(arg, NULL);
-
- if (port == 0 || port > 65535)
- exit_error(PARAMETER_PROBLEM, "Port `%s' not valid\n", arg);
-
- dash = strchr(arg, '-');
- if (!dash) {
- mr->range[0].min.tcp.port
- = mr->range[0].max.tcp.port
- = htons(port);
- } else {
- int maxport;
-
- maxport = atoi(dash + 1);
- if (maxport == 0 || maxport > 65535)
- exit_error(PARAMETER_PROBLEM,
- "Port `%s' not valid\n", dash+1);
- if (maxport < port)
- /* People are stupid. */
- exit_error(PARAMETER_PROBLEM,
- "Port range `%s' funky\n", arg);
- mr->range[0].min.tcp.port = htons(port);
- mr->range[0].max.tcp.port = htons(maxport);
- }
-}
-
-/* Function which parses command options; returns true if it
- ate an option */
-static int REDIRECT_parse(int c, char **argv, int invert, unsigned int *flags,
- const void *e, struct xt_entry_target **target)
-{
- const struct ipt_entry *entry = e;
- struct ip_nat_multi_range *mr
- = (struct ip_nat_multi_range *)(*target)->data;
- int portok;
-
- if (entry->ip.proto == IPPROTO_TCP
- || entry->ip.proto == IPPROTO_UDP
- || entry->ip.proto == IPPROTO_ICMP)
- portok = 1;
- else
- portok = 0;
-
- switch (c) {
- case '1':
- if (!portok)
- exit_error(PARAMETER_PROBLEM,
- "Need TCP or UDP with port specification");
-
- if (check_inverse(optarg, &invert, NULL, 0))
- exit_error(PARAMETER_PROBLEM,
- "Unexpected `!' after --to-ports");
-
- parse_ports(optarg, mr);
- if (*flags & IPT_REDIRECT_OPT_RANDOM)
- mr->range[0].flags |= IP_NAT_RANGE_PROTO_RANDOM;
- *flags |= IPT_REDIRECT_OPT_DEST;
- return 1;
-
- case '2':
- if (*flags & IPT_REDIRECT_OPT_DEST) {
- mr->range[0].flags |= IP_NAT_RANGE_PROTO_RANDOM;
- *flags |= IPT_REDIRECT_OPT_RANDOM;
- } else
- *flags |= IPT_REDIRECT_OPT_RANDOM;
- return 1;
-
- default:
- return 0;
- }
-}
-
-/* Prints out the targinfo. */
-static void REDIRECT_print(const void *ip, const struct xt_entry_target *target,
- int numeric)
-{
- struct ip_nat_multi_range *mr
- = (struct ip_nat_multi_range *)target->data;
- struct ip_nat_range *r = &mr->range[0];
-
- if (r->flags & IP_NAT_RANGE_PROTO_SPECIFIED) {
- printf("redir ports ");
- printf("%hu", ntohs(r->min.tcp.port));
- if (r->max.tcp.port != r->min.tcp.port)
- printf("-%hu", ntohs(r->max.tcp.port));
- printf(" ");
- if (mr->range[0].flags & IP_NAT_RANGE_PROTO_RANDOM)
- printf("random ");
- }
-}
-
-/* Saves the union ipt_targinfo in parsable form to stdout. */
-static void REDIRECT_save(const void *ip, const struct xt_entry_target *target)
-{
- struct ip_nat_multi_range *mr
- = (struct ip_nat_multi_range *)target->data;
- struct ip_nat_range *r = &mr->range[0];
-
- if (r->flags & IP_NAT_RANGE_PROTO_SPECIFIED) {
- printf("--to-ports ");
- printf("%hu", ntohs(r->min.tcp.port));
- if (r->max.tcp.port != r->min.tcp.port)
- printf("-%hu", ntohs(r->max.tcp.port));
- printf(" ");
- if (mr->range[0].flags & IP_NAT_RANGE_PROTO_RANDOM)
- printf("--random ");
- }
-}
-
-static struct xtables_target redirect_tg_reg = {
- .name = "REDIRECT",
- .version = XTABLES_VERSION,
- .family = PF_INET,
- .size = XT_ALIGN(sizeof(struct ip_nat_multi_range)),
- .userspacesize = XT_ALIGN(sizeof(struct ip_nat_multi_range)),
- .help = REDIRECT_help,
- .init = REDIRECT_init,
- .parse = REDIRECT_parse,
- .print = REDIRECT_print,
- .save = REDIRECT_save,
- .extra_opts = REDIRECT_opts,
-};
-
-void _init(void)
-{
- xtables_register_target(&redirect_tg_reg);
-}
git://git.onelab.eu / iptables.git / blobdiff