release/src/router/iptables/extensions/libipt_SECMARK.c

   1 /*
   2  * Shared library add-on to iptables to add SECMARK target support.
   3  *
   4  * Based on the MARK target.
   5  *
   6  * Copyright (C) 2006 Red Hat, Inc., James Morris <jmorris@redhat.com>
   7  */
   8 #include <stdio.h>
   9 #include <string.h>
  10 #include <stdlib.h>
  11 #include <getopt.h>
  12 #include <iptables.h>
  13 #include <linux/netfilter/xt_SECMARK.h>
  14
  15 #define PFX "SECMARK target: "
  16
  17 static void help(void)
  18 {
  19         printf(
  20 "SECMARK target v%s options:\n"
  21 "  --selctx value                     Set the SELinux security context\n"
  22 "\n",
  23 IPTABLES_VERSION);
  24 }
  25
  26 static struct option opts[] = {
  27         { "selctx", 1, 0, '1' },
  28         { 0 }
  29 };
  30
  31 /* Initialize the target. */
  32 static void init(struct ipt_entry_target *t, unsigned int *nfcache)
  33 { }
  34
  35 /*
  36  * Function which parses command options; returns true if it
  37  * ate an option.
  38  */
  39 static int parse(int c, char **argv, int invert, unsigned int *flags,
  40                  const struct ipt_entry *entry, struct ipt_entry_target **target)
  41 {
  42         struct xt_secmark_target_info *info =
  43                 (struct xt_secmark_target_info*)(*target)->data;
  44
  45         switch (c) {
  46         case '1':
  47                 if (*flags & SECMARK_MODE_SEL)
  48                         exit_error(PARAMETER_PROBLEM, PFX
  49                                    "Can't specify --selctx twice");
  50                 info->mode = SECMARK_MODE_SEL;
  51
  52                 if (strlen(optarg) > SECMARK_SELCTX_MAX-1)
  53                         exit_error(PARAMETER_PROBLEM, PFX
  54                                    "Maximum length %u exceeded by --selctx"
  55                                    " parameter (%zu)",
  56                                    SECMARK_SELCTX_MAX-1, strlen(optarg));
  57
  58                 strcpy(info->u.sel.selctx, optarg);
  59                 *flags |= SECMARK_MODE_SEL;
  60                 break;
  61         default:
  62                 return 0;
  63         }
  64
  65         return 1;
  66 }
  67
  68 static void final_check(unsigned int flags)
  69 {
  70         if (!flags)
  71                 exit_error(PARAMETER_PROBLEM, PFX "parameter required");
  72 }
  73
  74 static void print_secmark(struct xt_secmark_target_info *info)
  75 {
  76         switch (info->mode) {
  77         case SECMARK_MODE_SEL:
  78                 printf("selctx %s ", info->u.sel.selctx);\
  79                 break;
  80
  81         default:
  82                 exit_error(OTHER_PROBLEM, PFX "invalid mode %hhu\n", info->mode);
  83         }
  84 }
  85
  86 static void print(const struct ipt_ip *ip,
  87                   const struct ipt_entry_target *target, int numeric)
  88 {
  89         struct xt_secmark_target_info *info =
  90                 (struct xt_secmark_target_info*)(target)->data;
  91
  92         printf("SECMARK ");
  93         print_secmark(info);
  94 }
  95
  96 /* Saves the target info in parsable form to stdout. */
  97 static void save(const struct ipt_ip *ip, const struct ipt_entry_target *target)
  98 {
  99         struct xt_secmark_target_info *info =
 100                 (struct xt_secmark_target_info*)target->data;
 101
 102         printf("--");
 103         print_secmark(info);
 104 }
 105
 106 static struct iptables_target secmark = {
 107         .next           = NULL,
 108         .name           = "SECMARK",
 109         .version        = IPTABLES_VERSION,
 110         .revision       = 0,
 111         .size           = IPT_ALIGN(sizeof(struct xt_secmark_target_info)),
 112         .userspacesize  = IPT_ALIGN(sizeof(struct xt_secmark_target_info)),
 113         .help           = &help,
 114         .init           = &init,
 115         .parse          = &parse,
 116         .final_check    = &final_check,
 117         .print          = &print,
 118         .save           = &save,
 119         .extra_opts     = opts
 120 };
 121
 122 void _init(void)
 123 {
 124         register_target(&secmark);
 125 }