release/src/router/iptables/extensions/libip6t_mh.c

   1 /* Shared library add-on to ip6tables to add mobility header support. */
   2 /*
   3  * Copyright (C)2006 USAGI/WIDE Project
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Author:
  10  *      Masahide NAKAMURA @USAGI <masahide.nakamura.cz@hitachi.com>
  11  *
  12  * Based on libip6t_{icmpv6,udp}.c
  13  */
  14 #include <stdio.h>
  15 #include <netdb.h>
  16 #include <string.h>
  17 #include <stdlib.h>
  18 #include <getopt.h>
  19 #include <ip6tables.h>
  20 #include <linux/netfilter_ipv6/ip6_tables.h>
  21 #include <linux/netfilter_ipv6/ip6t_mh.h>
  22
  23 struct mh_name {
  24         const char *name;
  25         u_int8_t type;
  26 };
  27
  28 static const struct mh_name mh_names[] = {
  29         { "binding-refresh-request", 0, },
  30         /* Alias */ { "brr", 0, },
  31         { "home-test-init", 1, },
  32         /* Alias */ { "hoti", 1, },
  33         { "careof-test-init", 2, },
  34         /* Alias */ { "coti", 2, },
  35         { "home-test", 3, },
  36         /* Alias */ { "hot", 3, },
  37         { "careof-test", 4, },
  38         /* Alias */ { "cot", 4, },
  39         { "binding-update", 5, },
  40         /* Alias */ { "bu", 5, },
  41         { "binding-acknowledgement", 6, },
  42         /* Alias */ { "ba", 6, },
  43         { "binding-error", 7, },
  44         /* Alias */ { "be", 7, },
  45 };
  46
  47 static void print_types_all(void)
  48 {
  49         unsigned int i;
  50         printf("Valid MH types:");
  51
  52         for (i = 0; i < sizeof(mh_names)/sizeof(struct mh_name); i++) {
  53                 if (i && mh_names[i].type == mh_names[i-1].type)
  54                         printf(" (%s)", mh_names[i].name);
  55                 else
  56                         printf("\n%s", mh_names[i].name);
  57         }
  58         printf("\n");
  59 }
  60
  61 static void help(void)
  62 {
  63         printf(
  64 "MH v%s options:\n"
  65 " --mh-type [!] type[:type]     match mh type\n",
  66 IPTABLES_VERSION);
  67         print_types_all();
  68 }
  69
  70 static void init(struct ip6t_entry_match *m, unsigned int *nfcache)
  71 {
  72         struct ip6t_mh *mhinfo = (struct ip6t_mh *)m->data;
  73
  74         mhinfo->types[1] = 0xFF;
  75 }
  76
  77 static unsigned int name_to_type(const char *name)
  78 {
  79         int namelen = strlen(name);
  80         unsigned int limit = sizeof(mh_names)/sizeof(struct mh_name);
  81         unsigned int match = limit;
  82         unsigned int i;
  83
  84         for (i = 0; i < limit; i++) {
  85                 if (strncasecmp(mh_names[i].name, name, namelen) == 0) {
  86                         int len = strlen(mh_names[i].name);
  87                         if (match == limit || len == namelen)
  88                                 match = i;
  89                 }
  90         }
  91
  92         if (match != limit) {
  93                 return mh_names[match].type;
  94         } else {
  95                 unsigned int number;
  96
  97                 if (string_to_number(name, 0, 255, &number) == -1)
  98                         exit_error(PARAMETER_PROBLEM,
  99                                    "Invalid MH type `%s'\n", name);
 100                 return number;
 101         }
 102 }
 103
 104 static void parse_mh_types(const char *mhtype, u_int8_t *types)
 105 {
 106         char *buffer;
 107         char *cp;
 108
 109         buffer = strdup(mhtype);
 110         if ((cp = strchr(buffer, ':')) == NULL)
 111                 types[0] = types[1] = name_to_type(buffer);
 112         else {
 113                 *cp = '\0';
 114                 cp++;
 115
 116                 types[0] = buffer[0] ? name_to_type(buffer) : 0;
 117                 types[1] = cp[0] ? name_to_type(cp) : 0xFF;
 118
 119                 if (types[0] > types[1])
 120                         exit_error(PARAMETER_PROBLEM,
 121                                    "Invalid MH type range (min > max)");
 122         }
 123         free(buffer);
 124 }
 125
 126 #define MH_TYPES 0x01
 127
 128 static int parse(int c, char **argv, int invert, unsigned int *flags,
 129                  const struct ip6t_entry *entry,
 130                  unsigned int *nfcache,
 131                  struct ip6t_entry_match **match)
 132 {
 133         struct ip6t_mh *mhinfo = (struct ip6t_mh *)(*match)->data;
 134
 135         switch (c) {
 136         case '1':
 137                 if (*flags & MH_TYPES)
 138                         exit_error(PARAMETER_PROBLEM,
 139                                    "Only one `--mh-type' allowed");
 140                 check_inverse(optarg, &invert, &optind, 0);
 141                 parse_mh_types(argv[optind-1], mhinfo->types);
 142                 if (invert)
 143                         mhinfo->invflags |= IP6T_MH_INV_TYPE;
 144                 *flags |= MH_TYPES;
 145                 break;
 146
 147         default:
 148                 return 0;
 149         }
 150
 151         return 1;
 152 }
 153
 154 /* Final check; we don't care. */
 155 static void final_check(unsigned int flags)
 156 {
 157 }
 158
 159 static const char *type_to_name(u_int8_t type)
 160 {
 161         unsigned int i;
 162
 163         for (i = 0; i < sizeof(mh_names)/sizeof(struct mh_name); i++) {
 164                 if (mh_names[i].type == type)
 165                         return mh_names[i].name;
 166         }
 167
 168         return NULL;
 169 }
 170
 171 static void print_type(u_int8_t type, int numeric)
 172 {
 173         const char *name;
 174         if (numeric || !(name = type_to_name(type)))
 175                 printf("%u", type);
 176         else
 177                 printf("%s", name);
 178 }
 179
 180 static void print_types(u_int8_t min, u_int8_t max, int invert, int numeric)
 181 {
 182         const char *inv = invert ? "!" : "";
 183
 184         if (min != 0 || max != 0xFF || invert) {
 185                 if (min == max) {
 186                         printf("%s", inv);
 187                         print_type(min, numeric);
 188                 } else {
 189                         printf("%s", inv);
 190                         print_type(min, numeric);
 191                         printf(":");
 192                         print_type(max, numeric);
 193                 }
 194                 printf(" ");
 195         }
 196 }
 197
 198 static void print(const struct ip6t_ip6 *ip,
 199                   const struct ip6t_entry_match *match,
 200                   int numeric)
 201 {
 202         const struct ip6t_mh *mhinfo = (struct ip6t_mh *)match->data;
 203
 204         printf("mh ");
 205         print_types(mhinfo->types[0], mhinfo->types[1],
 206                     mhinfo->invflags & IP6T_MH_INV_TYPE,
 207                     numeric);
 208         if (mhinfo->invflags & ~IP6T_MH_INV_MASK)
 209                 printf("Unknown invflags: 0x%X ",
 210                        mhinfo->invflags & ~IP6T_MH_INV_MASK);
 211 }
 212
 213 static void save(const struct ip6t_ip6 *ip,
 214                  const struct ip6t_entry_match *match)
 215 {
 216         const struct ip6t_mh *mhinfo = (struct ip6t_mh *)match->data;
 217
 218         if (mhinfo->types[0] == 0 && mhinfo->types[1] == 0xFF)
 219                 return;
 220
 221         if (mhinfo->invflags & IP6T_MH_INV_TYPE)
 222                 printf("! ");
 223
 224         if (mhinfo->types[0] != mhinfo->types[1])
 225                 printf("--mh-type %u:%u ", mhinfo->types[0], mhinfo->types[1]);
 226         else
 227                 printf("--mh-type %u ", mhinfo->types[0]);
 228 }
 229
 230 static struct option opts[] = {
 231         { "mh-type", 1, 0, '1' },
 232         {0}
 233 };
 234
 235 static struct ip6tables_match mh = {
 236         .name           = "mh",
 237         .version        = IPTABLES_VERSION,
 238         .size           = IP6T_ALIGN(sizeof(struct ip6t_mh)),
 239         .userspacesize  = IP6T_ALIGN(sizeof(struct ip6t_mh)),
 240         .help           = &help,
 241         .init           = &init,
 242         .parse          = &parse,
 243         .final_check    = &final_check,
 244         .print          = &print,
 245         .save           = &save,
 246         .extra_opts     = opts,
 247 };
 248
 249 void _init(void)
 250 {
 251         register_match6(&mh);
 252 }