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

   1 /* Shared library add-on to iptables to add CLUSTERIP target support.
   2  * (C) 2003 by Harald Welte <laforge@gnumonks.org>
   3  *
   4  * Development of this code was funded by SuSE AG, http://www.suse.com/
   5  */
   6 #include <stdio.h>
   7 #include <string.h>
   8 #include <stdlib.h>
   9 #include <getopt.h>
  10 #include <stddef.h>
  11
  12 #if defined(__GLIBC__) && __GLIBC__ == 2
  13 #include <net/ethernet.h>
  14 #else
  15 #include <linux/if_ether.h>
  16 #endif
  17
  18 #include <iptables.h>
  19 #include <linux/netfilter_ipv4/ip_tables.h>
  20 #include "../include/linux/netfilter_ipv4/ipt_CLUSTERIP.h"
  21
  22 static void
  23 help(void)
  24 {
  25         printf(
  26 "CLUSTERIP target v%s options:\n"
  27 "  --new                         Create a new ClusterIP\n"
  28 "  --hashmode <mode>             Specify hashing mode\n"
  29 "                                       sourceip\n"
  30 "                                       sourceip-sourceport\n"
  31 "                                       sourceip-sourceport-destport\n"
  32 "  --clustermac <mac>            Set clusterIP MAC address\n"
  33 "  --total-nodes <num>           Set number of total nodes in cluster\n"
  34 "  --local-node <num>            Set the local node number\n"
  35 "  --hash-init <num>             Set init value of the Jenkins hash\n"
  36 "\n",
  37 IPTABLES_VERSION);
  38 }
  39
  40 #define PARAM_NEW       0x0001
  41 #define PARAM_HMODE     0x0002
  42 #define PARAM_MAC       0x0004
  43 #define PARAM_TOTALNODE 0x0008
  44 #define PARAM_LOCALNODE 0x0010
  45 #define PARAM_HASHINIT  0x0020
  46
  47 static struct option opts[] = {
  48         { "new", 0, 0, '1' },
  49         { "hashmode", 1, 0, '2' },
  50         { "clustermac", 1, 0, '3' },
  51         { "total-nodes", 1, 0, '4' },
  52         { "local-node", 1, 0, '5' },
  53         { "hash-init", 1, 0, '6' },
  54         { 0 }
  55 };
  56
  57 static void
  58 init(struct ipt_entry_target *t, unsigned int *nfcache)
  59 {
  60 }
  61
  62 static void
  63 parse_mac(const char *mac, char *macbuf)
  64 {
  65         unsigned int i = 0;
  66
  67         if (strlen(mac) != ETH_ALEN*3-1)
  68                 exit_error(PARAMETER_PROBLEM, "Bad mac address `%s'", mac);
  69
  70         for (i = 0; i < ETH_ALEN; i++) {
  71                 long number;
  72                 char *end;
  73
  74                 number = strtol(mac + i*3, &end, 16);
  75
  76                 if (end == mac + i*3 + 2
  77                     && number >= 0
  78                     && number <= 255)
  79                         macbuf[i] = number;
  80                 else
  81                         exit_error(PARAMETER_PROBLEM,
  82                                    "Bad mac address `%s'", mac);
  83         }
  84 }
  85
  86 static int
  87 parse(int c, char **argv, int invert, unsigned int *flags,
  88       const struct ipt_entry *entry,
  89       struct ipt_entry_target **target)
  90 {
  91         struct ipt_clusterip_tgt_info *cipinfo
  92                 = (struct ipt_clusterip_tgt_info *)(*target)->data;
  93
  94         switch (c) {
  95                 unsigned int num;
  96         case '1':
  97                 cipinfo->flags |= CLUSTERIP_FLAG_NEW;
  98                 if (*flags & PARAM_NEW)
  99                         exit_error(PARAMETER_PROBLEM, "Can only specify `--new' once\n");
 100                 *flags |= PARAM_NEW;
 101                 break;
 102         case '2':
 103                 if (!(*flags & PARAM_NEW))
 104                         exit_error(PARAMETER_PROBLEM, "Can only specify hashmode combined with `--new'\n");
 105                 if (*flags & PARAM_HMODE)
 106                         exit_error(PARAMETER_PROBLEM, "Can only specify hashmode once\n");
 107                 if (!strcmp(optarg, "sourceip"))
 108                         cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP;
 109                 else if (!strcmp(optarg, "sourceip-sourceport"))
 110                         cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP_SPT;
 111                 else if (!strcmp(optarg, "sourceip-sourceport-destport"))
 112                         cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP_SPT_DPT;
 113                 else
 114                         exit_error(PARAMETER_PROBLEM, "Unknown hashmode `%s'\n",
 115                                    optarg);
 116                 *flags |= PARAM_HMODE;
 117                 break;
 118         case '3':
 119                 if (!(*flags & PARAM_NEW))
 120                         exit_error(PARAMETER_PROBLEM, "Can only specify MAC combined with `--new'\n");
 121                 if (*flags & PARAM_MAC)
 122                         exit_error(PARAMETER_PROBLEM, "Can only specify MAC once\n");
 123                 parse_mac(optarg, (char *)cipinfo->clustermac);
 124                 if (!(cipinfo->clustermac[0] & 0x01))
 125                         exit_error(PARAMETER_PROBLEM, "MAC has to be a multicast ethernet address\n");
 126                 *flags |= PARAM_MAC;
 127                 break;
 128         case '4':
 129                 if (!(*flags & PARAM_NEW))
 130                         exit_error(PARAMETER_PROBLEM, "Can only specify node number combined with `--new'\n");
 131                 if (*flags & PARAM_TOTALNODE)
 132                         exit_error(PARAMETER_PROBLEM, "Can only specify total node number once\n");
 133                 if (string_to_number(optarg, 1, CLUSTERIP_MAX_NODES, &num) < 0)
 134                         exit_error(PARAMETER_PROBLEM, "Unable to parse `%s'\n", optarg);
 135                 cipinfo->num_total_nodes = (u_int16_t)num;
 136                 *flags |= PARAM_TOTALNODE;
 137                 break;
 138         case '5':
 139                 if (!(*flags & PARAM_NEW))
 140                         exit_error(PARAMETER_PROBLEM, "Can only specify node number combined with `--new'\n");
 141                 if (*flags & PARAM_LOCALNODE)
 142                         exit_error(PARAMETER_PROBLEM, "Can only specify local node number once\n");
 143                 if (string_to_number(optarg, 1, CLUSTERIP_MAX_NODES, &num) < 0)
 144                         exit_error(PARAMETER_PROBLEM, "Unable to parse `%s'\n", optarg);
 145                 cipinfo->num_local_nodes = 1;
 146                 cipinfo->local_nodes[0] = (u_int16_t)num;
 147                 *flags |= PARAM_LOCALNODE;
 148                 break;
 149         case '6':
 150                 if (!(*flags & PARAM_NEW))
 151                         exit_error(PARAMETER_PROBLEM, "Can only specify hash init value combined with `--new'\n");
 152                 if (*flags & PARAM_HASHINIT)
 153                         exit_error(PARAMETER_PROBLEM, "Can specify hash init value only once\n");
 154                 if (string_to_number(optarg, 0, UINT_MAX, &num) < 0)
 155                         exit_error(PARAMETER_PROBLEM, "Unable to parse `%s'\n", optarg);
 156                 cipinfo->hash_initval = num;
 157                 *flags |= PARAM_HASHINIT;
 158                 break;
 159         default:
 160                 return 0;
 161         }
 162
 163         return 1;
 164 }
 165
 166 static void
 167 final_check(unsigned int flags)
 168 {
 169         if (flags == 0)
 170                 return;
 171
 172         if ((flags & (PARAM_NEW|PARAM_HMODE|PARAM_MAC|PARAM_TOTALNODE|PARAM_LOCALNODE))
 173                 == (PARAM_NEW|PARAM_HMODE|PARAM_MAC|PARAM_TOTALNODE|PARAM_LOCALNODE))
 174                 return;
 175
 176         exit_error(PARAMETER_PROBLEM, "CLUSTERIP target: Invalid parameter combination\n");
 177 }
 178
 179 static char *hashmode2str(enum clusterip_hashmode mode)
 180 {
 181         char *retstr;
 182         switch (mode) {
 183                 case CLUSTERIP_HASHMODE_SIP:
 184                         retstr = "sourceip";
 185                         break;
 186                 case CLUSTERIP_HASHMODE_SIP_SPT:
 187                         retstr = "sourceip-sourceport";
 188                         break;
 189                 case CLUSTERIP_HASHMODE_SIP_SPT_DPT:
 190                         retstr = "sourceip-sourceport-destport";
 191                         break;
 192                 default:
 193                         retstr = "unknown-error";
 194                         break;
 195         }
 196         return retstr;
 197 }
 198
 199 static char *mac2str(const u_int8_t mac[ETH_ALEN])
 200 {
 201         static char buf[ETH_ALEN*3];
 202         sprintf(buf, "%02X:%02X:%02X:%02X:%02X:%02X",
 203                 mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
 204         return buf;
 205 }
 206
 207
 208 /* Prints out the targinfo. */
 209 static void
 210 print(const struct ipt_ip *ip,
 211       const struct ipt_entry_target *target,
 212       int numeric)
 213 {
 214         const struct ipt_clusterip_tgt_info *cipinfo =
 215                 (const struct ipt_clusterip_tgt_info *)target->data;
 216
 217         if (!cipinfo->flags & CLUSTERIP_FLAG_NEW) {
 218                 printf("CLUSTERIP");
 219                 return;
 220         }
 221
 222         printf("CLUSTERIP hashmode=%s clustermac=%s total_nodes=%u local_node=%u hash_init=%u",
 223                 hashmode2str(cipinfo->hash_mode),
 224                 mac2str(cipinfo->clustermac),
 225                 cipinfo->num_total_nodes,
 226                 cipinfo->local_nodes[0],
 227                 cipinfo->hash_initval);
 228 }
 229
 230 /* Saves the union ipt_targinfo in parsable form to stdout. */
 231 static void
 232 save(const struct ipt_ip *ip, const struct ipt_entry_target *target)
 233 {
 234         const struct ipt_clusterip_tgt_info *cipinfo =
 235                 (const struct ipt_clusterip_tgt_info *)target->data;
 236
 237         /* if this is not a new entry, we don't need to save target
 238          * parameters */
 239         if (!cipinfo->flags & CLUSTERIP_FLAG_NEW)
 240                 return;
 241
 242         printf("--new --hashmode %s --clustermac %s --total-nodes %d --local-node %d --hash-init %u",
 243                hashmode2str(cipinfo->hash_mode),
 244                mac2str(cipinfo->clustermac),
 245                cipinfo->num_total_nodes,
 246                cipinfo->local_nodes[0],
 247                cipinfo->hash_initval);
 248 }
 249
 250 static struct iptables_target clusterip = {
 251         .next           = NULL,
 252         .name           = "CLUSTERIP",
 253         .version        = IPTABLES_VERSION,
 254         .size           = IPT_ALIGN(sizeof(struct ipt_clusterip_tgt_info)),
 255         .userspacesize  = offsetof(struct ipt_clusterip_tgt_info, config),
 256         .help           = &help,
 257         .init           = &init,
 258         .parse          = &parse,
 259         .final_check    = &final_check,
 260         .print          = &print,
 261         .save           = &save,
 262         .extra_opts     = opts
 263 };
 264
 265 void _init(void)
 266 {
 267         register_target(&clusterip);
 268 }