libipt_DNAT: use guided option parser

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

diff --git a/extensions/libipt_DNAT.c b/extensions/libipt_DNAT.c
index 49c74e103ef6a742d166bb7407e93ea23f4e47f4..e7fd7c92e538986b81244ba256e9bbd5107b155c 100644 (file)
--- a/extensions/libipt_DNAT.c
+++ b/extensions/libipt_DNAT.c
@@ -1,18 +1,20 @@
-/* Shared library add-on to iptables to add destination-NAT support. */
-#include <stdbool.h>
 #include <stdio.h>
 #include <netdb.h>
 #include <string.h>
 #include <stdlib.h>
-#include <getopt.h>
 #include <xtables.h>
 #include <iptables.h> /* get_kernel_version */
 #include <limits.h> /* INT_MAX in ip_tables.h */
 #include <linux/netfilter_ipv4/ip_tables.h>
 #include <net/netfilter/nf_nat.h>
 
-#define IPT_DNAT_OPT_DEST 0x1
-#define IPT_DNAT_OPT_RANDOM 0x2
+enum {
+       O_TO_DEST = 0,
+       O_RANDOM,
+       O_PERSISTENT,
+       F_TO_DEST = 1 << O_TO_DEST,
+       F_RANDOM  = 1 << O_RANDOM,
+};
 
 /* Dest NAT data consists of a multi-range, indicating where to map
    to. */
@@ -31,11 +33,12 @@ static void DNAT_help(void)
 "[--random] [--persistent]\n");
 }
 
-static const struct option DNAT_opts[] = {
-       {.name = "to-destination", .has_arg = true,  .val = '1'},
-       {.name = "random",         .has_arg = false, .val = '2'},
-       {.name = "persistent",     .has_arg = false, .val = '3'},
-       XT_GETOPT_TABLEEND,
+static const struct xt_option_entry DNAT_opts[] = {
+       {.name = "to-destination", .id = O_TO_DEST, .type = XTTYPE_STRING,
+        .flags = XTOPT_MAND | XTOPT_MULTI},
+       {.name = "random", .id = O_RANDOM, .type = XTTYPE_NONE},
+       {.name = "persistent", .id = O_PERSISTENT, .type = XTTYPE_NONE},
+       XTOPT_TABLEEND,
 };
 
 static struct ipt_natinfo *
@@ -59,12 +62,15 @@ append_range(struct ipt_natinfo *info, const struct nf_nat_range *range)
 
 /* Ranges expected in network order. */
 static struct xt_entry_target *
-parse_to(char *arg, int portok, struct ipt_natinfo *info)
+parse_to(const char *orig_arg, int portok, struct ipt_natinfo *info)
 {
        struct nf_nat_range range;
-       char *colon, *dash, *error;
+       char *arg, *colon, *dash, *error;
        const struct in_addr *ip;
 
+       arg = strdup(orig_arg);
+       if (arg == NULL)
+               xtables_error(RESOURCE_PROBLEM, "strdup");
        memset(&range, 0, sizeof(range));
        colon = strchr(arg, ':');
 
@@ -107,8 +113,10 @@ parse_to(char *arg, int portok, struct ipt_natinfo *info)
                        range.max.tcp.port = htons(maxport);
                }
                /* Starts with a colon? No IP info...*/
-               if (colon == arg)
+               if (colon == arg) {
+                       free(arg);
                        return &(append_range(info, &range)->t);
+               }
                *colon = '\0';
        }
 
@@ -134,14 +142,14 @@ parse_to(char *arg, int portok, struct ipt_natinfo *info)
        } else
                range.max_ip = range.min_ip;
 
+       free(arg);
        return &(append_range(info, &range)->t);
 }
 
-static int DNAT_parse(int c, char **argv, int invert, unsigned int *flags,
-                      const void *e, struct xt_entry_target **target)
+static void DNAT_parse(struct xt_option_call *cb)
 {
-       const struct ipt_entry *entry = e;
-       struct ipt_natinfo *info = (void *)*target;
+       const struct ipt_entry *entry = cb->xt_entry;
+       struct ipt_natinfo *info = (void *)(*cb->target);
        int portok;
 
        if (entry->ip.proto == IPPROTO_TCP
@@ -153,46 +161,29 @@ static int DNAT_parse(int c, char **argv, int invert, unsigned int *flags,
        else
                portok = 0;
 
-       switch (c) {
-       case '1':
-               if (xtables_check_inverse(optarg, &invert, NULL, 0, argv))
-                       xtables_error(PARAMETER_PROBLEM,
-                                  "Unexpected `!' after --to-destination");
-
-               if (*flags & IPT_DNAT_OPT_DEST) {
+       xtables_option_parse(cb);
+       switch (cb->entry->id) {
+       case O_TO_DEST:
+               if (cb->xflags & F_TO_DEST) {
                        if (!kernel_version)
                                get_kernel_version();
                        if (kernel_version > LINUX_VERSION(2, 6, 10))
                                xtables_error(PARAMETER_PROBLEM,
                                           "Multiple --to-destination not supported");
                }
-               *target = parse_to(optarg, portok, info);
+               *cb->target = parse_to(cb->arg, portok, info);
                /* WTF do we need this for?? */
-               if (*flags & IPT_DNAT_OPT_RANDOM)
+               if (cb->xflags & F_RANDOM)
                        info->mr.range[0].flags |= IP_NAT_RANGE_PROTO_RANDOM;
-               *flags |= IPT_DNAT_OPT_DEST;
-               return 1;
-
-       case '2':
-               if (*flags & IPT_DNAT_OPT_DEST) {
+               break;
+       case O_RANDOM:
+               if (cb->xflags & F_TO_DEST)
                        info->mr.range[0].flags |= IP_NAT_RANGE_PROTO_RANDOM;
-                       *flags |= IPT_DNAT_OPT_RANDOM;
-               } else
-                       *flags |= IPT_DNAT_OPT_RANDOM;
-               return 1;
-
-       case '3':
+               break;
+       case O_PERSISTENT:
                info->mr.range[0].flags |= IP_NAT_RANGE_PERSISTENT;
-               return 1;
+               break;
        }
-       return 0;
-}
-
-static void DNAT_check(unsigned int flags)
-{
-       if (!(flags & IPT_DNAT_OPT_DEST))
-               xtables_error(PARAMETER_PROBLEM,
-                          "You must specify --to-destination");
 }
 
 static void print_range(const struct nf_nat_range *r)
@@ -253,11 +244,10 @@ static struct xtables_target dnat_tg_reg = {
        .size           = XT_ALIGN(sizeof(struct nf_nat_multi_range)),
        .userspacesize  = XT_ALIGN(sizeof(struct nf_nat_multi_range)),
        .help           = DNAT_help,
-       .parse          = DNAT_parse,
-       .final_check    = DNAT_check,
+       .x6_parse       = DNAT_parse,
        .print          = DNAT_print,
        .save           = DNAT_save,
-       .extra_opts     = DNAT_opts,
+       .x6_options     = DNAT_opts,
 };
 
 void _init(void)