--- /dev/null
+/* Shared library add-on to iptables to add UDP support. */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <xtables.h>
+#include <linux/netfilter/xt_tcpudp.h>
+
+/* Function which prints out usage message. */
+static void udp_help(void)
+{
+ printf(
+"udp match options:\n"
+" --source-port [!] port[:port]\n"
+" --sport ...\n"
+" match source port(s)\n"
+" --destination-port [!] port[:port]\n"
+" --dport ...\n"
+" match destination port(s)\n");
+}
+
+static const struct option udp_opts[] = {
+ { "source-port", 1, NULL, '1' },
+ { "sport", 1, NULL, '1' }, /* synonym */
+ { "destination-port", 1, NULL, '2' },
+ { "dport", 1, NULL, '2' }, /* synonym */
+ { .name = NULL }
+};
+
+static void
+parse_udp_ports(const char *portstring, u_int16_t *ports)
+{
+ char *buffer;
+ char *cp;
+
+ buffer = strdup(portstring);
+ if ((cp = strchr(buffer, ':')) == NULL)
+ ports[0] = ports[1] = parse_port(buffer, "udp");
+ else {
+ *cp = '\0';
+ cp++;
+
+ ports[0] = buffer[0] ? parse_port(buffer, "udp") : 0;
+ ports[1] = cp[0] ? parse_port(cp, "udp") : 0xFFFF;
+
+ if (ports[0] > ports[1])
+ exit_error(PARAMETER_PROBLEM,
+ "invalid portrange (min > max)");
+ }
+ free(buffer);
+}
+
+/* Initialize the match. */
+static void udp_init(struct xt_entry_match *m)
+{
+ struct xt_udp *udpinfo = (struct xt_udp *)m->data;
+
+ udpinfo->spts[1] = udpinfo->dpts[1] = 0xFFFF;
+}
+
+#define UDP_SRC_PORTS 0x01
+#define UDP_DST_PORTS 0x02
+
+/* Function which parses command options; returns true if it
+ ate an option */
+static int
+udp_parse(int c, char **argv, int invert, unsigned int *flags,
+ const void *entry, struct xt_entry_match **match)
+{
+ struct xt_udp *udpinfo = (struct xt_udp *)(*match)->data;
+
+ switch (c) {
+ case '1':
+ if (*flags & UDP_SRC_PORTS)
+ exit_error(PARAMETER_PROBLEM,
+ "Only one `--source-port' allowed");
+ check_inverse(optarg, &invert, &optind, 0);
+ parse_udp_ports(argv[optind-1], udpinfo->spts);
+ if (invert)
+ udpinfo->invflags |= XT_UDP_INV_SRCPT;
+ *flags |= UDP_SRC_PORTS;
+ break;
+
+ case '2':
+ if (*flags & UDP_DST_PORTS)
+ exit_error(PARAMETER_PROBLEM,
+ "Only one `--destination-port' allowed");
+ check_inverse(optarg, &invert, &optind, 0);
+ parse_udp_ports(argv[optind-1], udpinfo->dpts);
+ if (invert)
+ udpinfo->invflags |= XT_UDP_INV_DSTPT;
+ *flags |= UDP_DST_PORTS;
+ break;
+
+ default:
+ return 0;
+ }
+
+ return 1;
+}
+
+static char *
+port_to_service(int port)
+{
+ struct servent *service;
+
+ if ((service = getservbyport(htons(port), "udp")))
+ return service->s_name;
+
+ return NULL;
+}
+
+static void
+print_port(u_int16_t port, int numeric)
+{
+ char *service;
+
+ if (numeric || (service = port_to_service(port)) == NULL)
+ printf("%u", port);
+ else
+ printf("%s", service);
+}
+
+static void
+print_ports(const char *name, u_int16_t min, u_int16_t max,
+ int invert, int numeric)
+{
+ const char *inv = invert ? "!" : "";
+
+ if (min != 0 || max != 0xFFFF || invert) {
+ printf("%s", name);
+ if (min == max) {
+ printf(":%s", inv);
+ print_port(min, numeric);
+ } else {
+ printf("s:%s", inv);
+ print_port(min, numeric);
+ printf(":");
+ print_port(max, numeric);
+ }
+ printf(" ");
+ }
+}
+
+/* Prints out the union ipt_matchinfo. */
+static void
+udp_print(const void *ip, const struct xt_entry_match *match, int numeric)
+{
+ const struct xt_udp *udp = (struct xt_udp *)match->data;
+
+ printf("udp ");
+ print_ports("spt", udp->spts[0], udp->spts[1],
+ udp->invflags & XT_UDP_INV_SRCPT,
+ numeric);
+ print_ports("dpt", udp->dpts[0], udp->dpts[1],
+ udp->invflags & XT_UDP_INV_DSTPT,
+ numeric);
+ if (udp->invflags & ~XT_UDP_INV_MASK)
+ printf("Unknown invflags: 0x%X ",
+ udp->invflags & ~XT_UDP_INV_MASK);
+}
+
+/* Saves the union ipt_matchinfo in parsable form to stdout. */
+static void udp_save(const void *ip, const struct xt_entry_match *match)
+{
+ const struct xt_udp *udpinfo = (struct xt_udp *)match->data;
+
+ if (udpinfo->spts[0] != 0
+ || udpinfo->spts[1] != 0xFFFF) {
+ if (udpinfo->invflags & XT_UDP_INV_SRCPT)
+ printf("! ");
+ if (udpinfo->spts[0]
+ != udpinfo->spts[1])
+ printf("--sport %u:%u ",
+ udpinfo->spts[0],
+ udpinfo->spts[1]);
+ else
+ printf("--sport %u ",
+ udpinfo->spts[0]);
+ }
+
+ if (udpinfo->dpts[0] != 0
+ || udpinfo->dpts[1] != 0xFFFF) {
+ if (udpinfo->invflags & XT_UDP_INV_DSTPT)
+ printf("! ");
+ if (udpinfo->dpts[0]
+ != udpinfo->dpts[1])
+ printf("--dport %u:%u ",
+ udpinfo->dpts[0],
+ udpinfo->dpts[1]);
+ else
+ printf("--dport %u ",
+ udpinfo->dpts[0]);
+ }
+}
+
+static struct xtables_match udp_match = {
+ .family = AF_INET,
+ .name = "udp",
+ .version = XTABLES_VERSION,
+ .size = XT_ALIGN(sizeof(struct xt_udp)),
+ .userspacesize = XT_ALIGN(sizeof(struct xt_udp)),
+ .help = udp_help,
+ .init = udp_init,
+ .parse = udp_parse,
+ .print = udp_print,
+ .save = udp_save,
+ .extra_opts = udp_opts,
+};
+
+static struct xtables_match udp_match6 = {
+ .family = AF_INET6,
+ .name = "udp",
+ .version = XTABLES_VERSION,
+ .size = XT_ALIGN(sizeof(struct xt_udp)),
+ .userspacesize = XT_ALIGN(sizeof(struct xt_udp)),
+ .help = udp_help,
+ .init = udp_init,
+ .parse = udp_parse,
+ .print = udp_print,
+ .save = udp_save,
+ .extra_opts = udp_opts,
+};
+
+void
+_init(void)
+{
+ xtables_register_match(&udp_match);
+ xtables_register_match(&udp_match6);
+}
git://git.onelab.eu / iptables.git / blobdiff