release/src/router/iptables/extensions/libip6t_fuzzy.c

   1 /*
   2    Shared library add-on to iptables to add match support for the fuzzy match.
   3
   4    This file is distributed under the terms of the GNU General Public
   5    License (GPL). Copies of the GPL can be obtained from:
   6    ftp://prep.ai.mit.edu/pub/gnu/GPL
   7
   8 2002-08-07 Hime Aguiar e Oliveira Jr. <hime@engineer.com> : Initial version.
   9 2003-04-08 Maciej Soltysiak <solt@dns.toxicfilms.tv> : IPv6 Port
  10 2003-06-09 Hime Aguiar e Oliveira Jr. <hime@engineer.com> : Bug corrections in
  11 the save function , thanks to information given by Jean-Francois Patenaude.
  12
  13 */
  14
  15 #include <stdio.h>
  16 #include <netdb.h>
  17 #include <string.h>
  18 #include <stdlib.h>
  19 #include <syslog.h>
  20 #include <getopt.h>
  21 #include <ip6tables.h>
  22 #include <linux/netfilter_ipv6/ip6_tables.h>
  23 #include <linux/netfilter_ipv6/ip6t_fuzzy.h>
  24
  25
  26 static void
  27 help(void)
  28 {
  29         printf(
  30 "fuzzy v%s options:\n"
  31 "                      --lower-limit number (in packets per second)\n"
  32 "                      --upper-limit number\n"
  33 ,IPTABLES_VERSION);
  34 };
  35
  36 static struct option opts[] = {
  37         { .name = "lower-limit", .has_arg = 1, .flag = 0, .val = '1' },
  38         { .name = "upper-limit", .has_arg = 1, .flag = 0, .val = '2' },
  39         { .name = 0 }
  40 };
  41
  42 /* Initialize data structures */
  43 static void
  44 init(struct ip6t_entry_match *m, unsigned int *nfcache)
  45 {
  46         struct ip6t_fuzzy_info *presentinfo = (struct ip6t_fuzzy_info *)(m)->data;
  47         /*
  48          * Default rates ( I'll improve this very soon with something based
  49          * on real statistics of the running machine ) .
  50         */
  51
  52         presentinfo->minimum_rate = 1000;
  53         presentinfo->maximum_rate = 2000;
  54 }
  55
  56 #define IP6T_FUZZY_OPT_MINIMUM  0x01
  57 #define IP6T_FUZZY_OPT_MAXIMUM  0x02
  58
  59 static int
  60 parse(int c, char **argv, int invert, unsigned int *flags,
  61       const struct ip6t_entry *entry,
  62       unsigned int *nfcache,
  63       struct ip6t_entry_match **match)
  64 {
  65         struct ip6t_fuzzy_info *fuzzyinfo =
  66                 (struct ip6t_fuzzy_info *)(*match)->data;
  67
  68         u_int32_t num;
  69
  70         switch (c) {
  71
  72         case '1':
  73
  74         if (invert)
  75                 exit_error(PARAMETER_PROBLEM,"Can't specify ! --lower-limit");
  76
  77         if (*flags & IP6T_FUZZY_OPT_MINIMUM)
  78               exit_error(PARAMETER_PROBLEM,"Can't specify --lower-limit twice");
  79
  80         if (string_to_number(optarg,1,MAXFUZZYRATE,&num) == -1 || num < 1)
  81                         exit_error(PARAMETER_PROBLEM,"BAD --lower-limit");
  82
  83                 fuzzyinfo->minimum_rate = num ;
  84
  85                 *flags |= IP6T_FUZZY_OPT_MINIMUM;
  86
  87                 break;
  88
  89         case '2':
  90
  91         if (invert)
  92                 exit_error(PARAMETER_PROBLEM,"Can't specify ! --upper-limit");
  93
  94         if (*flags & IP6T_FUZZY_OPT_MAXIMUM)
  95            exit_error(PARAMETER_PROBLEM,"Can't specify --upper-limit twice");
  96
  97         if (string_to_number(optarg,1,MAXFUZZYRATE,&num) == -1 || num < 1)
  98                 exit_error(PARAMETER_PROBLEM,"BAD --upper-limit");
  99
 100                 fuzzyinfo->maximum_rate = num;
 101
 102                 *flags |= IP6T_FUZZY_OPT_MAXIMUM;
 103
 104                 break ;
 105
 106         default:
 107                 return 0;
 108         }
 109         return 1;
 110 }
 111
 112 static void final_check(unsigned int flags)
 113 {
 114 }
 115
 116 static void
 117 print(const struct ip6t_ip6 *ipv6,
 118       const struct ip6t_entry_match *match,
 119       int numeric)
 120 {
 121         const struct ip6t_fuzzy_info *fuzzyinfo
 122                 = (const struct ip6t_fuzzy_info *)match->data;
 123
 124         printf(" fuzzy: lower limit = %u pps - upper limit = %u pps ",
 125                 fuzzyinfo->minimum_rate, fuzzyinfo->maximum_rate);
 126 }
 127
 128 /* Saves the union ip6t_targinfo in parsable form to stdout. */
 129 static void
 130 save(const struct ip6t_ip6 *ipv6, const struct ip6t_entry_match *match)
 131 {
 132         const struct ip6t_fuzzy_info *fuzzyinfo
 133                 = (const struct ip6t_fuzzy_info *)match->data;
 134
 135         printf("--lower-limit %u --upper-limit %u ",
 136                 fuzzyinfo->minimum_rate, fuzzyinfo->maximum_rate);
 137 }
 138
 139 struct ip6tables_match fuzzy_match = {
 140         .name          = "fuzzy",
 141         .version       = IPTABLES_VERSION,
 142         .size          = IP6T_ALIGN(sizeof(struct ip6t_fuzzy_info)),
 143         .userspacesize = IP6T_ALIGN(sizeof(struct ip6t_fuzzy_info)),
 144         .help          = &help,
 145         .init          = &init,
 146         .parse         = &parse,
 147         .final_check   = &final_check,
 148         .print         = &print,
 149         .save          = &save,
 150         .extra_opts    = opts
 151 };
 152
 153 void _init(void)
 154 {
 155         register_match6(&fuzzy_match);
 156 }