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 <xtables.h>
  19 #include <linux/netfilter_ipv4/ipt_CLUSTERIP.h>
  20
  21 static void CLUSTERIP_help(void)
  22 {
  23         printf(
  24 "CLUSTERIP target options:\n"
  25 "  --new                         Create a new ClusterIP\n"
  26 "  --hashmode <mode>             Specify hashing mode\n"
  27 "                                       sourceip\n"
  28 "                                       sourceip-sourceport\n"
  29 "                                       sourceip-sourceport-destport\n"
  30 "  --clustermac <mac>            Set clusterIP MAC address\n"
  31 "  --total-nodes <num>           Set number of total nodes in cluster\n"
  32 "  --local-node <num>            Set the local node number\n"
  33 "  --hash-init <num>             Set init value of the Jenkins hash\n");
  34 }
  35
  36 #define PARAM_NEW       0x0001
  37 #define PARAM_HMODE     0x0002
  38 #define PARAM_MAC       0x0004
  39 #define PARAM_TOTALNODE 0x0008
  40 #define PARAM_LOCALNODE 0x0010
  41 #define PARAM_HASHINIT  0x0020
  42
  43 static const struct option CLUSTERIP_opts[] = {
  44         { "new", 0, NULL, '1' },
  45         { "hashmode", 1, NULL, '2' },
  46         { "clustermac", 1, NULL, '3' },
  47         { "total-nodes", 1, NULL, '4' },
  48         { "local-node", 1, NULL, '5' },
  49         { "hash-init", 1, NULL, '6' },
  50         { .name = NULL }
  51 };
  52
  53 static void
  54 parse_mac(const char *mac, char *macbuf)
  55 {
  56         unsigned int i = 0;
  57
  58         if (strlen(mac) != ETH_ALEN*3-1)
  59                 xtables_error(PARAMETER_PROBLEM, "Bad mac address \"%s\"", mac);
  60
  61         for (i = 0; i < ETH_ALEN; i++) {
  62                 long number;
  63                 char *end;
  64
  65                 number = strtol(mac + i*3, &end, 16);
  66
  67                 if (end == mac + i*3 + 2
  68                     && number >= 0
  69                     && number <= 255)
  70                         macbuf[i] = number;
  71                 else
  72                         xtables_error(PARAMETER_PROBLEM,
  73                                    "Bad mac address `%s'", mac);
  74         }
  75 }
  76
  77 static int CLUSTERIP_parse(int c, char **argv, int invert, unsigned int *flags,
  78                            const void *entry, struct xt_entry_target **target)
  79 {
  80         struct ipt_clusterip_tgt_info *cipinfo
  81                 = (struct ipt_clusterip_tgt_info *)(*target)->data;
  82
  83         switch (c) {
  84                 unsigned int num;
  85         case '1':
  86                 cipinfo->flags |= CLUSTERIP_FLAG_NEW;
  87                 if (*flags & PARAM_NEW)
  88                         xtables_error(PARAMETER_PROBLEM, "Can only specify \"--new\" once\n");
  89                 *flags |= PARAM_NEW;
  90                 break;
  91         case '2':
  92                 if (!(*flags & PARAM_NEW))
  93                         xtables_error(PARAMETER_PROBLEM, "Can only specify hashmode combined with \"--new\"\n");
  94                 if (*flags & PARAM_HMODE)
  95                         xtables_error(PARAMETER_PROBLEM, "Can only specify hashmode once\n");
  96                 if (!strcmp(optarg, "sourceip"))
  97                         cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP;
  98                 else if (!strcmp(optarg, "sourceip-sourceport"))
  99                         cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP_SPT;
 100                 else if (!strcmp(optarg, "sourceip-sourceport-destport"))
 101                         cipinfo->hash_mode = CLUSTERIP_HASHMODE_SIP_SPT_DPT;
 102                 else
 103                         xtables_error(PARAMETER_PROBLEM, "Unknown hashmode \"%s\"\n",
 104                                    optarg);
 105                 *flags |= PARAM_HMODE;
 106                 break;
 107         case '3':
 108                 if (!(*flags & PARAM_NEW))
 109                         xtables_error(PARAMETER_PROBLEM, "Can only specify MAC combined with \"--new\"\n");
 110                 if (*flags & PARAM_MAC)
 111                         xtables_error(PARAMETER_PROBLEM, "Can only specify MAC once\n");
 112                 parse_mac(optarg, (char *)cipinfo->clustermac);
 113                 if (!(cipinfo->clustermac[0] & 0x01))
 114                         xtables_error(PARAMETER_PROBLEM, "MAC has to be a multicast ethernet address\n");
 115                 *flags |= PARAM_MAC;
 116                 break;
 117         case '4':
 118                 if (!(*flags & PARAM_NEW))
 119                         xtables_error(PARAMETER_PROBLEM, "Can only specify node number combined with \"--new\"\n");
 120                 if (*flags & PARAM_TOTALNODE)
 121                         xtables_error(PARAMETER_PROBLEM, "Can only specify total node number once\n");
 122                 if (!xtables_strtoui(optarg, NULL, &num, 1, CLUSTERIP_MAX_NODES))
 123                         xtables_error(PARAMETER_PROBLEM, "Unable to parse \"%s\"\n", optarg);
 124                 cipinfo->num_total_nodes = num;
 125                 *flags |= PARAM_TOTALNODE;
 126                 break;
 127         case '5':
 128                 if (!(*flags & PARAM_NEW))
 129                         xtables_error(PARAMETER_PROBLEM, "Can only specify node number combined with \"--new\"\n");
 130                 if (*flags & PARAM_LOCALNODE)
 131                         xtables_error(PARAMETER_PROBLEM, "Can only specify local node number once\n");
 132                 if (!xtables_strtoui(optarg, NULL, &num, 1, CLUSTERIP_MAX_NODES))
 133                         xtables_error(PARAMETER_PROBLEM, "Unable to parse \"%s\"\n", optarg);
 134                 cipinfo->num_local_nodes = 1;
 135                 cipinfo->local_nodes[0] = num;
 136                 *flags |= PARAM_LOCALNODE;
 137                 break;
 138         case '6':
 139                 if (!(*flags & PARAM_NEW))
 140                         xtables_error(PARAMETER_PROBLEM, "Can only specify hash init value combined with \"--new\"\n");
 141                 if (*flags & PARAM_HASHINIT)
 142                         xtables_error(PARAMETER_PROBLEM, "Can specify hash init value only once\n");
 143                 if (!xtables_strtoui(optarg, NULL, &num, 0, UINT_MAX))
 144                         xtables_error(PARAMETER_PROBLEM, "Unable to parse \"%s\"\n", optarg);
 145                 cipinfo->hash_initval = num;
 146                 *flags |= PARAM_HASHINIT;
 147                 break;
 148         default:
 149                 return 0;
 150         }
 151
 152         return 1;
 153 }
 154
 155 static void CLUSTERIP_check(unsigned int flags)
 156 {
 157         if (flags == 0)
 158                 return;
 159
 160         if ((flags & (PARAM_NEW|PARAM_HMODE|PARAM_MAC|PARAM_TOTALNODE|PARAM_LOCALNODE))
 161                 == (PARAM_NEW|PARAM_HMODE|PARAM_MAC|PARAM_TOTALNODE|PARAM_LOCALNODE))
 162                 return;
 163
 164         xtables_error(PARAMETER_PROBLEM, "CLUSTERIP target: Invalid parameter combination\n");
 165 }
 166
 167 static char *hashmode2str(enum clusterip_hashmode mode)
 168 {
 169         char *retstr;
 170         switch (mode) {
 171                 case CLUSTERIP_HASHMODE_SIP:
 172                         retstr = "sourceip";
 173                         break;
 174                 case CLUSTERIP_HASHMODE_SIP_SPT:
 175                         retstr = "sourceip-sourceport";
 176                         break;
 177                 case CLUSTERIP_HASHMODE_SIP_SPT_DPT:
 178                         retstr = "sourceip-sourceport-destport";
 179                         break;
 180                 default:
 181                         retstr = "unknown-error";
 182                         break;
 183         }
 184         return retstr;
 185 }
 186
 187 static char *mac2str(const u_int8_t mac[ETH_ALEN])
 188 {
 189         static char buf[ETH_ALEN*3];
 190         sprintf(buf, "%02X:%02X:%02X:%02X:%02X:%02X",
 191                 mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
 192         return buf;
 193 }
 194
 195 static void CLUSTERIP_print(const void *ip,
 196                             const struct xt_entry_target *target, int numeric)
 197 {
 198         const struct ipt_clusterip_tgt_info *cipinfo =
 199                 (const struct ipt_clusterip_tgt_info *)target->data;
 200
 201         if (!cipinfo->flags & CLUSTERIP_FLAG_NEW) {
 202                 printf("CLUSTERIP");
 203                 return;
 204         }
 205
 206         printf("CLUSTERIP hashmode=%s clustermac=%s total_nodes=%u local_node=%u hash_init=%u",
 207                 hashmode2str(cipinfo->hash_mode),
 208                 mac2str(cipinfo->clustermac),
 209                 cipinfo->num_total_nodes,
 210                 cipinfo->local_nodes[0],
 211                 cipinfo->hash_initval);
 212 }
 213
 214 static void CLUSTERIP_save(const void *ip, const struct xt_entry_target *target)
 215 {
 216         const struct ipt_clusterip_tgt_info *cipinfo =
 217                 (const struct ipt_clusterip_tgt_info *)target->data;
 218
 219         /* if this is not a new entry, we don't need to save target
 220          * parameters */
 221         if (!cipinfo->flags & CLUSTERIP_FLAG_NEW)
 222                 return;
 223
 224         printf("--new --hashmode %s --clustermac %s --total-nodes %d --local-node %d --hash-init %u",
 225                hashmode2str(cipinfo->hash_mode),
 226                mac2str(cipinfo->clustermac),
 227                cipinfo->num_total_nodes,
 228                cipinfo->local_nodes[0],
 229                cipinfo->hash_initval);
 230 }
 231
 232 static struct xtables_target clusterip_tg_reg = {
 233         .name           = "CLUSTERIP",
 234         .version        = XTABLES_VERSION,
 235         .family         = NFPROTO_IPV4,
 236         .size           = XT_ALIGN(sizeof(struct ipt_clusterip_tgt_info)),
 237         .userspacesize  = offsetof(struct ipt_clusterip_tgt_info, config),
 238         .help           = CLUSTERIP_help,
 239         .parse          = CLUSTERIP_parse,
 240         .final_check    = CLUSTERIP_check,
 241         .print          = CLUSTERIP_print,
 242         .save           = CLUSTERIP_save,
 243         .extra_opts     = CLUSTERIP_opts,
 244 };
 245
 246 void _init(void)
 247 {
 248         xtables_register_target(&clusterip_tg_reg);
 249 }