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authorrusty <rusty>2000-06-04 17:38:47 +0000
committerrusty <rusty>2000-06-04 17:38:47 +0000
commit029ab3acbe586115a9ffede96a2d2e265a366c1d (patch)
tree5146bd31539a11b1fdc3f16e3a381269e7756aac /extensions/libip6t_udp.c
parentafd3df140f8565e57ef1d2bf222b47939a346bc3 (diff)
Phil Blundell's new ipv6 extensions.
Diffstat (limited to 'extensions/libip6t_udp.c')
-rw-r--r--extensions/libip6t_udp.c253
1 files changed, 253 insertions, 0 deletions
diff --git a/extensions/libip6t_udp.c b/extensions/libip6t_udp.c
new file mode 100644
index 0000000..f2c0b6a
--- /dev/null
+++ b/extensions/libip6t_udp.c
@@ -0,0 +1,253 @@
+/* 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 <ip6tables.h>
+#include <linux/netfilter_ipv6/ip6_tables.h>
+
+/* Function which prints out usage message. */
+static void
+help(void)
+{
+ printf(
+"UDP v%s 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",
+NETFILTER_VERSION);
+}
+
+static struct option opts[] = {
+ { "source-port", 1, 0, '1' },
+ { "sport", 1, 0, '1' }, /* synonym */
+ { "destination-port", 1, 0, '2' },
+ { "dport", 1, 0, '2' }, /* synonym */
+ {0}
+};
+
+static int
+service_to_port(const char *name)
+{
+ struct servent *service;
+
+ if ((service = getservbyname(name, "udp")) != NULL)
+ return ntohs((unsigned short) service->s_port);
+
+ return -1;
+}
+
+static u_int16_t
+parse_udp_port(const char *port)
+{
+ int portnum;
+
+ if ((portnum = string_to_number(port, 0, 65535)) != -1 ||
+ (portnum = service_to_port(port)) != -1)
+ return (u_int16_t)portnum;
+
+ exit_error(PARAMETER_PROBLEM,
+ "invalid UDP port/service `%s' specified", port);
+ }
+
+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_udp_port(buffer);
+ else {
+ *cp = '\0';
+ cp++;
+
+ ports[0] = buffer[0] ? parse_udp_port(buffer) : 0;
+ ports[1] = cp[0] ? parse_udp_port(cp) : 0xFFFF;
+ }
+ free(buffer);
+}
+
+/* Initialize the match. */
+static void
+init(struct ip6t_entry_match *m, unsigned int *nfcache)
+{
+ struct ip6t_udp *udpinfo = (struct ip6t_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
+parse(int c, char **argv, int invert, unsigned int *flags,
+ const struct ip6t_entry *entry,
+ unsigned int *nfcache,
+ struct ip6t_entry_match **match)
+{
+ struct ip6t_udp *udpinfo = (struct ip6t_udp *)(*match)->data;
+
+ switch (c) {
+ case '1':
+ if (*flags & UDP_SRC_PORTS)
+ exit_error(PARAMETER_PROBLEM,
+ "Only one `--source-port' allowed");
+ if (check_inverse(optarg, &invert))
+ optind++;
+ parse_udp_ports(argv[optind-1], udpinfo->spts);
+ if (invert)
+ udpinfo->invflags |= IP6T_UDP_INV_SRCPT;
+ *flags |= UDP_SRC_PORTS;
+ *nfcache |= NFC_IP6_SRC_PT;
+ break;
+
+ case '2':
+ if (*flags & UDP_DST_PORTS)
+ exit_error(PARAMETER_PROBLEM,
+ "Only one `--destination-port' allowed");
+ if (check_inverse(optarg, &invert))
+ optind++;
+ parse_udp_ports(argv[optind-1], udpinfo->dpts);
+ if (invert)
+ udpinfo->invflags |= IP6T_UDP_INV_DSTPT;
+ *flags |= UDP_DST_PORTS;
+ *nfcache |= NFC_IP6_DST_PT;
+ break;
+
+ default:
+ return 0;
+ }
+
+ return 1;
+}
+
+/* Final check; we don't care. */
+static void
+final_check(unsigned int flags)
+{
+}
+
+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
+print(const struct ip6t_ip6 *ip,
+ const struct ip6t_entry_match *match, int numeric)
+{
+ const struct ip6t_udp *udp = (struct ip6t_udp *)match->data;
+
+ printf("udp ");
+ print_ports("spt", udp->spts[0], udp->spts[1],
+ udp->invflags & IP6T_UDP_INV_SRCPT,
+ numeric);
+ print_ports("dpt", udp->dpts[0], udp->dpts[1],
+ udp->invflags & IP6T_UDP_INV_DSTPT,
+ numeric);
+ if (udp->invflags & ~IP6T_UDP_INV_MASK)
+ printf("Unknown invflags: 0x%X ",
+ udp->invflags & ~IP6T_UDP_INV_MASK);
+}
+
+/* Saves the union ipt_matchinfo in parsable form to stdout. */
+static void save(const struct ip6t_ip6 *ip, const struct ip6t_entry_match *match)
+{
+ const struct ip6t_udp *udpinfo = (struct ip6t_udp *)match->data;
+
+ if (udpinfo->spts[0] != 0
+ && udpinfo->spts[1] != 0xFFFF) {
+ if (udpinfo->invflags & IP6T_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 & IP6T_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]);
+ }
+}
+
+struct ip6tables_match udp
+= { NULL,
+ "udp",
+ NETFILTER_VERSION,
+ sizeof(struct ip6t_udp),
+ sizeof(struct ip6t_udp),
+ &help,
+ &init,
+ &parse,
+ &final_check,
+ &print,
+ &save,
+ opts
+};
+
+void
+_init(void)
+{
+ register_match6(&udp);
+}