libipt_realm: use guided option parser

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

diff --git a/extensions/libipt_realm.c b/extensions/libipt_realm.c
index 17b1754e69a99e31b3efd8b1a2d69013f0404ca3..b60c57eeaa32661c4996d8a139c1349caf2a990b 100644 (file)
--- a/extensions/libipt_realm.c
+++ b/extensions/libipt_realm.c
@@ -1,12 +1,7 @@
-/* Shared library add-on to iptables to add realm matching support. */
-#include <stdbool.h>
 #include <stdio.h>
-#include <netdb.h>
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
-#include <ctype.h>
-#include <getopt.h>
 #if defined(__GLIBC__) && __GLIBC__ == 2
 #include <net/ethernet.h>
 #else
@@ -15,6 +10,10 @@
 #include <xtables.h>
 #include <linux/netfilter_ipv4/ipt_realm.h>
 
+enum {
+       O_REALM = 0,
+};
+
 static void realm_help(void)
 {
        printf(
@@ -23,165 +22,49 @@ static void realm_help(void)
 "                              Match realm\n");
 }
 
-static const struct option realm_opts[] = {
-       {.name = "realm", .has_arg = true, .val = '1'},
-       XT_GETOPT_TABLEEND,
-};
-
-struct realmname { 
-       int     id;
-       char*   name;
-       int     len;
-       struct realmname* next;
+static const struct xt_option_entry realm_opts[] = {
+       {.name = "realm", .id = O_REALM, .type = XTTYPE_STRING,
+        .flags = XTOPT_MAND | XTOPT_INVERT},
+       XTOPT_TABLEEND,
 };
 
 /* array of realms from /etc/iproute2/rt_realms */
-static struct realmname *realms;
-/* 1 if loading failed */
-static int rdberr;
+static struct xtables_lmap *realms;
 
-static void load_realms(void)
+static void realm_init(struct xt_entry_match *m)
 {
-       const char* rfnm = "/etc/iproute2/rt_realms";
-       char buf[512];
-       FILE *fil;
-       char *cur, *nxt;
-       int id;
-       struct realmname *oldnm = NULL, *newnm = NULL;
-
-       fil = fopen(rfnm, "re");
-       if (!fil) {
-               rdberr = 1;
-               return;
-       }
-
-       while (fgets(buf, sizeof(buf), fil)) {
-               cur = buf;
-               while ((*cur == ' ') || (*cur == '\t'))
-                       cur++;
-               if ((*cur == '#') || (*cur == '\n') || (*cur == 0))
-                       continue;
-
-               /* iproute2 allows hex and dec format */
-               errno = 0;
-               id = strtoul(cur, &nxt, strncmp(cur, "0x", 2) ? 10 : 16);
-               if ((nxt == cur) || errno)
-                       continue;
-
-               /* same boundaries as in iproute2 */
-               if (id < 0 || id > 255)
-                       continue;
-               cur = nxt;
-
-               if (!isspace(*cur))
-                       continue;
-               while ((*cur == ' ') || (*cur == '\t'))
-                       cur++;
-               if ((*cur == '#') || (*cur == '\n') || (*cur == 0))
-                       continue;
-               nxt = cur;
-               while ((*nxt != 0) && !isspace(*nxt))
-                       nxt++;
-               if (nxt == cur)
-                       continue;
-
-               /* found valid data */
-               newnm = malloc(sizeof(struct realmname));
-               if (newnm == NULL) {
-                       perror("libipt_realm: malloc failed");
-                       exit(1);
-               }
-               newnm->id = id;
-               newnm->len = nxt - cur;
-               newnm->name = malloc(newnm->len + 1);
-               if (newnm->name == NULL) {
-                       perror("libipt_realm: malloc failed");
-                       exit(1);
-               }
-               strncpy(newnm->name, cur, newnm->len);
-               newnm->name[newnm->len] = 0;
-               newnm->next = NULL;
-
-               if (oldnm)
-                       oldnm->next = newnm;
-               else
-                       realms = newnm;
-               oldnm = newnm;
-       }
-
-       fclose(fil);
+       const char file[] = "/etc/iproute2/rt_realms";
+       realms = xtables_lmap_init(file);
+       if (realms == NULL && errno != ENOENT)
+               fprintf(stderr, "Warning: %s: %s\n", file, strerror(errno));
 }
 
-/* get realm id for name, -1 if error/not found */
-static int realm_name2id(const char* name)
+static void realm_parse(struct xt_option_call *cb)
 {
-       struct realmname* cur;
-
-       if ((realms == NULL) && (rdberr == 0))
-               load_realms();
-       cur = realms;
-       if (cur == NULL)
-               return -1;
-       while (cur) {
-               if (!strncmp(name, cur->name, cur->len + 1))
-                       return cur->id;
-               cur = cur->next;
-       }
-       return -1;
-}
-
-/* get realm name for id, NULL if error/not found */
-static const char *realm_id2name(int id)
-{
-       struct realmname* cur;
-
-       if ((realms == NULL) && (rdberr == 0))
-               load_realms();
-       cur = realms;
-       if (cur == NULL)
-               return NULL;
-       while (cur) {
-               if (id == cur->id)
-                       return cur->name;
-               cur = cur->next;
-       }
-       return NULL;
-}
-
-static int realm_parse(int c, char **argv, int invert, unsigned int *flags,
-                       const void *entry, struct xt_entry_match **match)
-{
-       struct ipt_realm_info *realminfo = (struct ipt_realm_info *)(*match)->data;
+       struct ipt_realm_info *realminfo = cb->data;
        int id;
+       char *end;
 
-       switch (c) {
-               char *end;
-       case '1':
-               xtables_check_inverse(optarg, &invert, &optind, 0, argv);
-               end = optarg = optarg;
-               realminfo->id = strtoul(optarg, &end, 0);
-               if (end != optarg && (*end == '/' || *end == '\0')) {
-                       if (*end == '/')
-                               realminfo->mask = strtoul(end+1, &end, 0);
-                       else
-                               realminfo->mask = 0xffffffff;
-                       if (*end != '\0' || end == optarg)
-                               xtables_error(PARAMETER_PROBLEM,
-                                          "Bad realm value `%s'", optarg);
-               } else {
-                       id = realm_name2id(optarg);
-                       if (id == -1)
-                               xtables_error(PARAMETER_PROBLEM,
-                                          "Realm `%s' not found", optarg);
-                       realminfo->id = id;
+       xtables_option_parse(cb);
+       realminfo->id = strtoul(cb->arg, &end, 0);
+       if (end != cb->arg && (*end == '/' || *end == '\0')) {
+               if (*end == '/')
+                       realminfo->mask = strtoul(end+1, &end, 0);
+               else
                        realminfo->mask = 0xffffffff;
-               }
-               if (invert)
-                       realminfo->invert = 1;
-               *flags = 1;
-               break;
+               if (*end != '\0' || end == cb->arg)
+                       xtables_error(PARAMETER_PROBLEM,
+                                  "Bad realm value \"%s\"", cb->arg);
+       } else {
+               id = xtables_lmap_name2id(realms, cb->arg);
+               if (id == -1)
+                       xtables_error(PARAMETER_PROBLEM,
+                                  "Realm \"%s\" not found", cb->arg);
+               realminfo->id = id;
+               realminfo->mask = 0xffffffff;
        }
-       return 1;
+       if (cb->invert)
+               realminfo->invert = 1;
 }
 
 static void
@@ -193,7 +76,7 @@ print_realm(unsigned long id, unsigned long mask, int numeric)
                printf(" 0x%lx/0x%lx", id, mask);
        else {
                if (numeric == 0)
-                       name = realm_id2name(id);
+                       name = xtables_lmap_id2name(realms, id);
                if (name)
                        printf(" %s", name);
                else
@@ -224,13 +107,6 @@ static void realm_save(const void *ip, const struct xt_entry_match *match)
        print_realm(ri->id, ri->mask, 0);
 }
 
-static void realm_check(unsigned int flags)
-{
-       if (!flags)
-               xtables_error(PARAMETER_PROBLEM,
-                          "realm match: You must specify `--realm'");
-}
-
 static struct xtables_match realm_mt_reg = {
        .name           = "realm",
        .version        = XTABLES_VERSION,
@@ -238,11 +114,11 @@ static struct xtables_match realm_mt_reg = {
        .size           = XT_ALIGN(sizeof(struct ipt_realm_info)),
        .userspacesize  = XT_ALIGN(sizeof(struct ipt_realm_info)),
        .help           = realm_help,
-       .parse          = realm_parse,
-       .final_check    = realm_check,
+       .init           = realm_init,
        .print          = realm_print,
        .save           = realm_save,
-       .extra_opts     = realm_opts,
+       .x6_parse       = realm_parse,
+       .x6_options     = realm_opts,
 };
 
 void _init(void)