libxt_string: use guided option parser

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

diff --git a/extensions/libxt_string.c b/extensions/libxt_string.c
index 1030d2e308c587dbc1758d1a994e08c4907d143a..eef0b081b1f541aa850e73fbf5bc7587adcf109f 100644 (file)
--- a/extensions/libxt_string.c
+++ b/extensions/libxt_string.c
@@ -20,18 +20,25 @@
  *             updated to work with slightly modified
  *             ipt_string_info.
  */
-#define _GNU_SOURCE 1
-#include <stdbool.h>
 #include <stdio.h>
-#include <netdb.h>
 #include <string.h>
 #include <stdlib.h>
-#include <getopt.h>
 #include <ctype.h>
 #include <xtables.h>
-#include <stddef.h>
 #include <linux/netfilter/xt_string.h>
 
+enum {
+       O_FROM = 0,
+       O_TO,
+       O_ALGO,
+       O_ICASE,
+       O_STRING,
+       O_HEX_STRING,
+       F_STRING     = 1 << O_STRING,
+       F_HEX_STRING = 1 << O_HEX_STRING,
+       F_OP_ANY     = F_STRING | F_HEX_STRING,
+};
+
 static void string_help(void)
 {
        printf(
@@ -44,15 +51,22 @@ static void string_help(void)
 "[!] --hex-string string      Match a hex string in a packet\n");
 }
 
-static const struct option string_opts[] = {
-       {.name = "from",       .has_arg = true,  .val = '1'},
-       {.name = "to",         .has_arg = true,  .val = '2'},
-       {.name = "algo",       .has_arg = true,  .val = '3'},
-       {.name = "string",     .has_arg = true,  .val = '4'},
-       {.name = "hex-string", .has_arg = true,  .val = '5'},
-       {.name = "icase",      .has_arg = false, .val = '6'},
-       XT_GETOPT_TABLEEND,
+#define s struct xt_string_info
+static const struct xt_option_entry string_opts[] = {
+       {.name = "from", .id = O_FROM, .type = XTTYPE_UINT16,
+        .flags = XTOPT_PUT, XTOPT_POINTER(s, from_offset)},
+       {.name = "to", .id = O_TO, .type = XTTYPE_UINT16,
+        .flags = XTOPT_PUT, XTOPT_POINTER(s, to_offset)},
+       {.name = "algo", .id = O_ALGO, .type = XTTYPE_STRING,
+        .flags = XTOPT_MAND | XTOPT_PUT, XTOPT_POINTER(s, algo)},
+       {.name = "string", .id = O_STRING, .type = XTTYPE_STRING,
+        .flags = XTOPT_INVERT, .excl = F_HEX_STRING},
+       {.name = "hex-string", .id = O_HEX_STRING, .type = XTTYPE_STRING,
+        .flags = XTOPT_INVERT, .excl = F_STRING},
+       {.name = "icase", .id = O_ICASE, .type = XTTYPE_NONE},
+       XTOPT_TABLEEND,
 };
+#undef s
 
 static void string_init(struct xt_entry_match *m)
 {
@@ -73,17 +87,6 @@ parse_string(const char *s, struct xt_string_info *info)
        xtables_error(PARAMETER_PROBLEM, "STRING too long \"%s\"", s);
 }
 
-static void
-parse_algo(const char *s, struct xt_string_info *info)
-{
-       /* xt_string needs \0 for algo name */
-       if (strlen(s) < XT_STRING_MAX_ALGO_NAME_SIZE) {
-               strncpy(info->algo, s, XT_STRING_MAX_ALGO_NAME_SIZE);
-               return;
-       }
-       xtables_error(PARAMETER_PROBLEM, "ALGO too long \"%s\"", s);
-}
-
 static void
 parse_hex_string(const char *s, struct xt_string_info *info)
 {
@@ -162,94 +165,47 @@ parse_hex_string(const char *s, struct xt_string_info *info)
        info->patlen = sindex;
 }
 
-#define STRING 0x1
-#define ALGO   0x2
-#define FROM   0x4
-#define TO     0x8
-#define ICASE  0x10
-
-static int
-string_parse(int c, char **argv, int invert, unsigned int *flags,
-             const void *entry, struct xt_entry_match **match)
+static void string_parse(struct xt_option_call *cb)
 {
-       struct xt_string_info *stringinfo =
-           (struct xt_string_info *)(*match)->data;
-       const int revision = (*match)->u.user.revision;
+       struct xt_string_info *stringinfo = cb->data;
+       const unsigned int revision = (*cb->match)->u.user.revision;
 
-       switch (c) {
-       case '1':
-               if (*flags & FROM)
-                       xtables_error(PARAMETER_PROBLEM,
-                                  "Can't specify multiple --from");
-               stringinfo->from_offset = atoi(optarg);
-               *flags |= FROM;
-               break;
-       case '2':
-               if (*flags & TO)
-                       xtables_error(PARAMETER_PROBLEM,
-                                  "Can't specify multiple --to");
-               stringinfo->to_offset = atoi(optarg);
-               *flags |= TO;
-               break;
-       case '3':
-               if (*flags & ALGO)
-                       xtables_error(PARAMETER_PROBLEM,
-                                  "Can't specify multiple --algo");
-               parse_algo(optarg, stringinfo);
-               *flags |= ALGO;
-               break;
-       case '4':
-               if (*flags & STRING)
-                       xtables_error(PARAMETER_PROBLEM,
-                                  "Can't specify multiple --string");
-               xtables_check_inverse(optarg, &invert, &optind, 0, argv);
-               parse_string(optarg, stringinfo);
-               if (invert) {
+       xtables_option_parse(cb);
+       switch (cb->entry->id) {
+       case O_STRING:
+               parse_string(cb->arg, stringinfo);
+               if (cb->invert) {
                        if (revision == 0)
                                stringinfo->u.v0.invert = 1;
                        else
                                stringinfo->u.v1.flags |= XT_STRING_FLAG_INVERT;
                }
-               *flags |= STRING;
                break;
-
-       case '5':
-               if (*flags & STRING)
-                       xtables_error(PARAMETER_PROBLEM,
-                                  "Can't specify multiple --hex-string");
-
-               xtables_check_inverse(optarg, &invert, &optind, 0, argv);
-               parse_hex_string(optarg, stringinfo);  /* sets length */
-               if (invert) {
+       case O_HEX_STRING:
+               parse_hex_string(cb->arg, stringinfo);  /* sets length */
+               if (cb->invert) {
                        if (revision == 0)
                                stringinfo->u.v0.invert = 1;
                        else
                                stringinfo->u.v1.flags |= XT_STRING_FLAG_INVERT;
                }
-               *flags |= STRING;
                break;
-
-       case '6':
+       case O_ICASE:
                if (revision == 0)
                        xtables_error(VERSION_PROBLEM,
                                   "Kernel doesn't support --icase");
 
                stringinfo->u.v1.flags |= XT_STRING_FLAG_IGNORECASE;
-               *flags |= ICASE;
                break;
        }
-       return 1;
 }
 
-static void string_check(unsigned int flags)
+static void string_check(struct xt_fcheck_call *cb)
 {
-       if (!(flags & STRING))
+       if (!(cb->xflags & F_OP_ANY))
                xtables_error(PARAMETER_PROBLEM,
                           "STRING match: You must specify `--string' or "
                           "`--hex-string'");
-       if (!(flags & ALGO))
-               xtables_error(PARAMETER_PROBLEM,
-                          "STRING match: You must specify `--algo'");
 }
 
 /* Test to see if the string contains non-printable chars or quotes */
@@ -357,11 +313,11 @@ static struct xtables_match string_mt_reg[] = {
                .userspacesize = offsetof(struct xt_string_info, config),
                .help          = string_help,
                .init          = string_init,
-               .parse         = string_parse,
-               .final_check   = string_check,
                .print         = string_print,
                .save          = string_save,
-               .extra_opts    = string_opts,
+               .x6_parse      = string_parse,
+               .x6_fcheck     = string_check,
+               .x6_options    = string_opts,
        },
        {
                .name          = "string",
@@ -372,11 +328,11 @@ static struct xtables_match string_mt_reg[] = {
                .userspacesize = offsetof(struct xt_string_info, config),
                .help          = string_help,
                .init          = string_init,
-               .parse         = string_parse,
-               .final_check   = string_check,
                .print         = string_print,
                .save          = string_save,
-               .extra_opts    = string_opts,
+               .x6_parse      = string_parse,
+               .x6_fcheck     = string_check,
+               .x6_options    = string_opts,
        },
 };