/* ip6tables match extension for limiting packets per destination * * (C) 2003-2004 by Harald Welte <laforge@netfilter.org> * * Development of this code was funded by Astaro AG, http://www.astaro.com/ * * Based on ipt_limit.c by * Jérôme de Vivie <devivie@info.enserb.u-bordeaux.fr> * Hervé Eychenne <rv@wallfire.org> * * Error corections by nmalykh@bilim.com (22.01.2005) */ #define _BSD_SOURCE 1 #define _ISOC99_SOURCE 1 #include <math.h> #include <stdbool.h> #include <stdint.h> #include <stdio.h> #include <string.h> #include <stdlib.h> #include <xtables.h> #include <linux/netfilter/x_tables.h> #include <linux/netfilter/xt_hashlimit.h> #define XT_HASHLIMIT_BURST 5 #define XT_HASHLIMIT_BURST_MAX 10000 #define XT_HASHLIMIT_BYTE_EXPIRE 15 #define XT_HASHLIMIT_BYTE_EXPIRE_BURST 60 /* miliseconds */ #define XT_HASHLIMIT_GCINTERVAL 1000 struct hashlimit_mt_udata { uint32_t mult; }; static void hashlimit_help(void) { printf( "hashlimit match options:\n" "--hashlimit <avg> max average match rate\n" " [Packets per second unless followed by \n" " /sec /minute /hour /day postfixes]\n" "--hashlimit-mode <mode> mode is a comma-separated list of\n" " dstip,srcip,dstport,srcport\n" "--hashlimit-name <name> name for /proc/net/ipt_hashlimit/\n" "[--hashlimit-burst <num>] number to match in a burst, default %u\n" "[--hashlimit-htable-size <num>] number of hashtable buckets\n" "[--hashlimit-htable-max <num>] number of hashtable entries\n" "[--hashlimit-htable-gcinterval] interval between garbage collection runs\n" "[--hashlimit-htable-expire] after which time are idle entries expired?\n", XT_HASHLIMIT_BURST); } enum { O_UPTO = 0, O_ABOVE, O_LIMIT, O_MODE, O_SRCMASK, O_DSTMASK, O_NAME, O_BURST, O_HTABLE_SIZE, O_HTABLE_MAX, O_HTABLE_GCINT, O_HTABLE_EXPIRE, F_BURST = 1 << O_BURST, F_UPTO = 1 << O_UPTO, F_ABOVE = 1 << O_ABOVE, F_HTABLE_EXPIRE = 1 << O_HTABLE_EXPIRE, }; static void hashlimit_mt_help(void) { printf( "hashlimit match options:\n" " --hashlimit-upto <avg> max average match rate\n" " [Packets per second unless followed by \n" " /sec /minute /hour /day postfixes]\n" " --hashlimit-above <avg> min average match rate\n" " --hashlimit-mode <mode> mode is a comma-separated list of\n" " dstip,srcip,dstport,srcport (or none)\n" " --hashlimit-srcmask <length> source address grouping prefix length\n" " --hashlimit-dstmask <length> destination address grouping prefix length\n" " --hashlimit-name <name> name for /proc/net/ipt_hashlimit\n" " --hashlimit-burst <num> number to match in a burst, default %u\n" " --hashlimit-htable-size <num> number of hashtable buckets\n" " --hashlimit-htable-max <num> number of hashtable entries\n" " --hashlimit-htable-gcinterval interval between garbage collection runs\n" " --hashlimit-htable-expire after which time are idle entries expired?\n" "\n", XT_HASHLIMIT_BURST); } #define s struct xt_hashlimit_info static const struct xt_option_entry hashlimit_opts[] = { {.name = "hashlimit", .id = O_UPTO, .excl = F_ABOVE, .type = XTTYPE_STRING}, {.name = "hashlimit-burst", .id = O_BURST, .type = XTTYPE_UINT32, .min = 1, .max = XT_HASHLIMIT_BURST_MAX, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.burst)}, {.name = "hashlimit-htable-size", .id = O_HTABLE_SIZE, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.size)}, {.name = "hashlimit-htable-max", .id = O_HTABLE_MAX, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.max)}, {.name = "hashlimit-htable-gcinterval", .id = O_HTABLE_GCINT, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.gc_interval)}, {.name = "hashlimit-htable-expire", .id = O_HTABLE_EXPIRE, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.expire)}, {.name = "hashlimit-mode", .id = O_MODE, .type = XTTYPE_STRING, .flags = XTOPT_MAND}, {.name = "hashlimit-name", .id = O_NAME, .type = XTTYPE_STRING, .flags = XTOPT_MAND | XTOPT_PUT, XTOPT_POINTER(s, name), .min = 1}, XTOPT_TABLEEND, }; #undef s #define s struct xt_hashlimit_mtinfo1 static const struct xt_option_entry hashlimit_mt_opts[] = { {.name = "hashlimit-upto", .id = O_UPTO, .excl = F_ABOVE, .type = XTTYPE_STRING, .flags = XTOPT_INVERT}, {.name = "hashlimit-above", .id = O_ABOVE, .excl = F_UPTO, .type = XTTYPE_STRING, .flags = XTOPT_INVERT}, {.name = "hashlimit", .id = O_UPTO, .excl = F_ABOVE, .type = XTTYPE_STRING, .flags = XTOPT_INVERT}, /* old name */ {.name = "hashlimit-srcmask", .id = O_SRCMASK, .type = XTTYPE_PLEN}, {.name = "hashlimit-dstmask", .id = O_DSTMASK, .type = XTTYPE_PLEN}, {.name = "hashlimit-burst", .id = O_BURST, .type = XTTYPE_STRING}, {.name = "hashlimit-htable-size", .id = O_HTABLE_SIZE, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.size)}, {.name = "hashlimit-htable-max", .id = O_HTABLE_MAX, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.max)}, {.name = "hashlimit-htable-gcinterval", .id = O_HTABLE_GCINT, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.gc_interval)}, {.name = "hashlimit-htable-expire", .id = O_HTABLE_EXPIRE, .type = XTTYPE_UINT32, .flags = XTOPT_PUT, XTOPT_POINTER(s, cfg.expire)}, {.name = "hashlimit-mode", .id = O_MODE, .type = XTTYPE_STRING}, {.name = "hashlimit-name", .id = O_NAME, .type = XTTYPE_STRING, .flags = XTOPT_MAND | XTOPT_PUT, XTOPT_POINTER(s, name), .min = 1}, XTOPT_TABLEEND, }; #undef s static uint32_t cost_to_bytes(uint32_t cost) { uint32_t r; r = cost ? UINT32_MAX / cost : UINT32_MAX; r = (r - 1) << XT_HASHLIMIT_BYTE_SHIFT; return r; } static uint64_t bytes_to_cost(uint32_t bytes) { uint32_t r = bytes >> XT_HASHLIMIT_BYTE_SHIFT; return UINT32_MAX / (r+1); } static uint32_t get_factor(int chr) { switch (chr) { case 'm': return 1024 * 1024; case 'k': return 1024; } return 1; } static void burst_error(void) { xtables_error(PARAMETER_PROBLEM, "bad value for option " "\"--hashlimit-burst\", or out of range (1-%u).", XT_HASHLIMIT_BURST_MAX); } static uint32_t parse_burst(const char *burst, struct xt_hashlimit_mtinfo1 *info) { uintmax_t v; char *end; if (!xtables_strtoul(burst, &end, &v, 1, UINT32_MAX) || (*end == 0 && v > XT_HASHLIMIT_BURST_MAX)) burst_error(); v *= get_factor(*end); if (v > UINT32_MAX) xtables_error(PARAMETER_PROBLEM, "bad value for option " "\"--hashlimit-burst\", value \"%s\" too large " "(max %umb).", burst, UINT32_MAX/1024/1024); return v; } static bool parse_bytes(const char *rate, uint32_t *val, struct hashlimit_mt_udata *ud) { unsigned int factor = 1; uint64_t tmp; int r; const char *mode = strstr(rate, "b/s"); if (!mode || mode == rate) return false; mode--; r = atoi(rate); if (r == 0) return false; factor = get_factor(*mode); tmp = (uint64_t) r * factor; if (tmp > UINT32_MAX) xtables_error(PARAMETER_PROBLEM, "Rate value too large \"%llu\" (max %u)\n", (unsigned long long)tmp, UINT32_MAX); *val = bytes_to_cost(tmp); if (*val == 0) xtables_error(PARAMETER_PROBLEM, "Rate too high \"%s\"\n", rate); ud->mult = XT_HASHLIMIT_BYTE_EXPIRE; return true; } static int parse_rate(const char *rate, uint32_t *val, struct hashlimit_mt_udata *ud) { const char *delim; uint32_t r; ud->mult = 1; /* Seconds by default. */ delim = strchr(rate, '/'); if (delim) { if (strlen(delim+1) == 0) return 0; if (strncasecmp(delim+1, "second", strlen(delim+1)) == 0) ud->mult = 1; else if (strncasecmp(delim+1, "minute", strlen(delim+1)) == 0) ud->mult = 60; else if (strncasecmp(delim+1, "hour", strlen(delim+1)) == 0) ud->mult = 60*60; else if (strncasecmp(delim+1, "day", strlen(delim+1)) == 0) ud->mult = 24*60*60; else return 0; } r = atoi(rate); if (!r) return 0; *val = XT_HASHLIMIT_SCALE * ud->mult / r; if (*val == 0) /* * The rate maps to infinity. (1/day is the minimum they can * specify, so we are ok at that end). */ xtables_error(PARAMETER_PROBLEM, "Rate too fast \"%s\"\n", rate); return 1; } static void hashlimit_init(struct xt_entry_match *m) { struct xt_hashlimit_info *r = (struct xt_hashlimit_info *)m->data; r->cfg.burst = XT_HASHLIMIT_BURST; r->cfg.gc_interval = XT_HASHLIMIT_GCINTERVAL; } static void hashlimit_mt4_init(struct xt_entry_match *match) { struct xt_hashlimit_mtinfo1 *info = (void *)match->data; info->cfg.mode = 0; info->cfg.burst = XT_HASHLIMIT_BURST; info->cfg.gc_interval = XT_HASHLIMIT_GCINTERVAL; info->cfg.srcmask = 32; info->cfg.dstmask = 32; } static void hashlimit_mt6_init(struct xt_entry_match *match) { struct xt_hashlimit_mtinfo1 *info = (void *)match->data; info->cfg.mode = 0; info->cfg.burst = XT_HASHLIMIT_BURST; info->cfg.gc_interval = XT_HASHLIMIT_GCINTERVAL; info->cfg.srcmask = 128; info->cfg.dstmask = 128; } /* Parse a 'mode' parameter into the required bitmask */ static int parse_mode(uint32_t *mode, const char *option_arg) { char *tok; char *arg = strdup(option_arg); if (!arg) return -1; for (tok = strtok(arg, ",|"); tok; tok = strtok(NULL, ",|")) { if (!strcmp(tok, "dstip")) *mode |= XT_HASHLIMIT_HASH_DIP; else if (!strcmp(tok, "srcip")) *mode |= XT_HASHLIMIT_HASH_SIP; else if (!strcmp(tok, "srcport")) *mode |= XT_HASHLIMIT_HASH_SPT; else if (!strcmp(tok, "dstport")) *mode |= XT_HASHLIMIT_HASH_DPT; else { free(arg); return -1; } } free(arg); return 0; } static void hashlimit_parse(struct xt_option_call *cb) { struct xt_hashlimit_info *info = cb->data; xtables_option_parse(cb); switch (cb->entry->id) { case O_UPTO: if (!parse_rate(cb->arg, &info->cfg.avg, cb->udata)) xtables_param_act(XTF_BAD_VALUE, "hashlimit", "--hashlimit-upto", cb->arg); break; case O_MODE: if (parse_mode(&info->cfg.mode, cb->arg) < 0) xtables_param_act(XTF_BAD_VALUE, "hashlimit", "--hashlimit-mode", cb->arg); break; } } static void hashlimit_mt_parse(struct xt_option_call *cb) { struct xt_hashlimit_mtinfo1 *info = cb->data; xtables_option_parse(cb); switch (cb->entry->id) { case O_BURST: info->cfg.burst = parse_burst(cb->arg, info); break; case O_UPTO: if (cb->invert) info->cfg.mode |= XT_HASHLIMIT_INVERT; if (parse_bytes(cb->arg, &info->cfg.avg, cb->udata)) info->cfg.mode |= XT_HASHLIMIT_BYTES; else if (!parse_rate(cb->arg, &info->cfg.avg, cb->udata)) xtables_param_act(XTF_BAD_VALUE, "hashlimit", "--hashlimit-upto", cb->arg); break; case O_ABOVE: if (!cb->invert) info->cfg.mode |= XT_HASHLIMIT_INVERT; if (parse_bytes(cb->arg, &info->cfg.avg, cb->udata)) info->cfg.mode |= XT_HASHLIMIT_BYTES; else if (!parse_rate(cb->arg, &info->cfg.avg, cb->udata)) xtables_param_act(XTF_BAD_VALUE, "hashlimit", "--hashlimit-above", cb->arg); break; case O_MODE: if (parse_mode(&info->cfg.mode, cb->arg) < 0) xtables_param_act(XTF_BAD_VALUE, "hashlimit", "--hashlimit-mode", cb->arg); break; case O_SRCMASK: info->cfg.srcmask = cb->val.hlen; break; case O_DSTMASK: info->cfg.dstmask = cb->val.hlen; break; } } static void hashlimit_check(struct xt_fcheck_call *cb) { const struct hashlimit_mt_udata *udata = cb->udata; struct xt_hashlimit_info *info = cb->data; if (!(cb->xflags & (F_UPTO | F_ABOVE))) xtables_error(PARAMETER_PROBLEM, "You have to specify --hashlimit"); if (!(cb->xflags & F_HTABLE_EXPIRE)) info->cfg.expire = udata->mult * 1000; /* from s to msec */ } static void hashlimit_mt_check(struct xt_fcheck_call *cb) { const struct hashlimit_mt_udata *udata = cb->udata; struct xt_hashlimit_mtinfo1 *info = cb->data; if (!(cb->xflags & (F_UPTO | F_ABOVE))) xtables_error(PARAMETER_PROBLEM, "You have to specify --hashlimit"); if (!(cb->xflags & F_HTABLE_EXPIRE)) info->cfg.expire = udata->mult * 1000; /* from s to msec */ if (info->cfg.mode & XT_HASHLIMIT_BYTES) { uint32_t burst = 0; if (cb->xflags & F_BURST) { if (info->cfg.burst < cost_to_bytes(info->cfg.avg)) xtables_error(PARAMETER_PROBLEM, "burst cannot be smaller than %ub", cost_to_bytes(info->cfg.avg)); burst = info->cfg.burst; burst /= cost_to_bytes(info->cfg.avg); if (info->cfg.burst % cost_to_bytes(info->cfg.avg)) burst++; if (!(cb->xflags & F_HTABLE_EXPIRE)) info->cfg.expire = XT_HASHLIMIT_BYTE_EXPIRE_BURST * 1000; } info->cfg.burst = burst; } else if (info->cfg.burst > XT_HASHLIMIT_BURST_MAX) burst_error(); } static const struct rates { const char *name; uint32_t mult; } rates[] = { { "day", XT_HASHLIMIT_SCALE*24*60*60 }, { "hour", XT_HASHLIMIT_SCALE*60*60 }, { "min", XT_HASHLIMIT_SCALE*60 }, { "sec", XT_HASHLIMIT_SCALE } }; static uint32_t print_rate(uint32_t period) { unsigned int i; if (period == 0) { printf(" %f", INFINITY); return 0; } for (i = 1; i < ARRAY_SIZE(rates); ++i) if (period > rates[i].mult || rates[i].mult/period < rates[i].mult%period) break; printf(" %u/%s", rates[i-1].mult / period, rates[i-1].name); /* return in msec */ return rates[i-1].mult / XT_HASHLIMIT_SCALE * 1000; } static const struct { const char *name; uint32_t thresh; } units[] = { { "m", 1024 * 1024 }, { "k", 1024 }, { "", 1 }, }; static uint32_t print_bytes(uint32_t avg, uint32_t burst, const char *prefix) { unsigned int i; unsigned long long r; r = cost_to_bytes(avg); for (i = 0; i < ARRAY_SIZE(units) -1; ++i) if (r >= units[i].thresh && bytes_to_cost(r & ~(units[i].thresh - 1)) == avg) break; printf(" %llu%sb/s", r/units[i].thresh, units[i].name); if (burst == 0) return XT_HASHLIMIT_BYTE_EXPIRE * 1000; r *= burst; printf(" %s", prefix); for (i = 0; i < ARRAY_SIZE(units) -1; ++i) if (r >= units[i].thresh) break; printf("burst %llu%sb", r / units[i].thresh, units[i].name); return XT_HASHLIMIT_BYTE_EXPIRE_BURST * 1000; } static void print_mode(unsigned int mode, char separator) { bool prevmode = false; putchar(' '); if (mode & XT_HASHLIMIT_HASH_SIP) { fputs("srcip", stdout); prevmode = 1; } if (mode & XT_HASHLIMIT_HASH_SPT) { if (prevmode) putchar(separator); fputs("srcport", stdout); prevmode = 1; } if (mode & XT_HASHLIMIT_HASH_DIP) { if (prevmode) putchar(separator); fputs("dstip", stdout); prevmode = 1; } if (mode & XT_HASHLIMIT_HASH_DPT) { if (prevmode) putchar(separator); fputs("dstport", stdout); } } static void hashlimit_print(const void *ip, const struct xt_entry_match *match, int numeric) { const struct xt_hashlimit_info *r = (const void *)match->data; uint32_t quantum; fputs(" limit: avg", stdout); quantum = print_rate(r->cfg.avg); printf(" burst %u", r->cfg.burst); fputs(" mode", stdout); print_mode(r->cfg.mode, '-'); if (r->cfg.size) printf(" htable-size %u", r->cfg.size); if (r->cfg.max) printf(" htable-max %u", r->cfg.max); if (r->cfg.gc_interval != XT_HASHLIMIT_GCINTERVAL) printf(" htable-gcinterval %u", r->cfg.gc_interval); if (r->cfg.expire != quantum) printf(" htable-expire %u", r->cfg.expire); } static void hashlimit_mt_print(const struct xt_hashlimit_mtinfo1 *info, unsigned int dmask) { uint32_t quantum; if (info->cfg.mode & XT_HASHLIMIT_INVERT) fputs(" limit: above", stdout); else fputs(" limit: up to", stdout); if (info->cfg.mode & XT_HASHLIMIT_BYTES) { quantum = print_bytes(info->cfg.avg, info->cfg.burst, ""); } else { quantum = print_rate(info->cfg.avg); printf(" burst %u", info->cfg.burst); } if (info->cfg.mode & (XT_HASHLIMIT_HASH_SIP | XT_HASHLIMIT_HASH_SPT | XT_HASHLIMIT_HASH_DIP | XT_HASHLIMIT_HASH_DPT)) { fputs(" mode", stdout); print_mode(info->cfg.mode, '-'); } if (info->cfg.size != 0) printf(" htable-size %u", info->cfg.size); if (info->cfg.max != 0) printf(" htable-max %u", info->cfg.max); if (info->cfg.gc_interval != XT_HASHLIMIT_GCINTERVAL) printf(" htable-gcinterval %u", info->cfg.gc_interval); if (info->cfg.expire != quantum) printf(" htable-expire %u", info->cfg.expire); if (info->cfg.srcmask != dmask) printf(" srcmask %u", info->cfg.srcmask); if (info->cfg.dstmask != dmask) printf(" dstmask %u", info->cfg.dstmask); } static void hashlimit_mt4_print(const void *ip, const struct xt_entry_match *match, int numeric) { const struct xt_hashlimit_mtinfo1 *info = (const void *)match->data; hashlimit_mt_print(info, 32); } static void hashlimit_mt6_print(const void *ip, const struct xt_entry_match *match, int numeric) { const struct xt_hashlimit_mtinfo1 *info = (const void *)match->data; hashlimit_mt_print(info, 128); } static void hashlimit_save(const void *ip, const struct xt_entry_match *match) { const struct xt_hashlimit_info *r = (const void *)match->data; uint32_t quantum; fputs(" --hashlimit", stdout); quantum = print_rate(r->cfg.avg); printf(" --hashlimit-burst %u", r->cfg.burst); fputs(" --hashlimit-mode", stdout); print_mode(r->cfg.mode, ','); printf(" --hashlimit-name %s", r->name); if (r->cfg.size) printf(" --hashlimit-htable-size %u", r->cfg.size); if (r->cfg.max) printf(" --hashlimit-htable-max %u", r->cfg.max); if (r->cfg.gc_interval != XT_HASHLIMIT_GCINTERVAL) printf(" --hashlimit-htable-gcinterval %u", r->cfg.gc_interval); if (r->cfg.expire != quantum) printf(" --hashlimit-htable-expire %u", r->cfg.expire); } static void hashlimit_mt_save(const struct xt_hashlimit_mtinfo1 *info, unsigned int dmask) { uint32_t quantum; if (info->cfg.mode & XT_HASHLIMIT_INVERT) fputs(" --hashlimit-above", stdout); else fputs(" --hashlimit-upto", stdout); if (info->cfg.mode & XT_HASHLIMIT_BYTES) { quantum = print_bytes(info->cfg.avg, info->cfg.burst, "--hashlimit-"); } else { quantum = print_rate(info->cfg.avg); printf(" --hashlimit-burst %u", info->cfg.burst); } if (info->cfg.mode & (XT_HASHLIMIT_HASH_SIP | XT_HASHLIMIT_HASH_SPT | XT_HASHLIMIT_HASH_DIP | XT_HASHLIMIT_HASH_DPT)) { fputs(" --hashlimit-mode", stdout); print_mode(info->cfg.mode, ','); } printf(" --hashlimit-name %s", info->name); if (info->cfg.size != 0) printf(" --hashlimit-htable-size %u", info->cfg.size); if (info->cfg.max != 0) printf(" --hashlimit-htable-max %u", info->cfg.max); if (info->cfg.gc_interval != XT_HASHLIMIT_GCINTERVAL) printf(" --hashlimit-htable-gcinterval %u", info->cfg.gc_interval); if (info->cfg.expire != quantum) printf(" --hashlimit-htable-expire %u", info->cfg.expire); if (info->cfg.srcmask != dmask) printf(" --hashlimit-srcmask %u", info->cfg.srcmask); if (info->cfg.dstmask != dmask) printf(" --hashlimit-dstmask %u", info->cfg.dstmask); } static void hashlimit_mt4_save(const void *ip, const struct xt_entry_match *match) { const struct xt_hashlimit_mtinfo1 *info = (const void *)match->data; hashlimit_mt_save(info, 32); } static void hashlimit_mt6_save(const void *ip, const struct xt_entry_match *match) { const struct xt_hashlimit_mtinfo1 *info = (const void *)match->data; hashlimit_mt_save(info, 128); } static struct xtables_match hashlimit_mt_reg[] = { { .family = NFPROTO_UNSPEC, .name = "hashlimit", .version = XTABLES_VERSION, .revision = 0, .size = XT_ALIGN(sizeof(struct xt_hashlimit_info)), .userspacesize = offsetof(struct xt_hashlimit_info, hinfo), .help = hashlimit_help, .init = hashlimit_init, .x6_parse = hashlimit_parse, .x6_fcheck = hashlimit_check, .print = hashlimit_print, .save = hashlimit_save, .x6_options = hashlimit_opts, .udata_size = sizeof(struct hashlimit_mt_udata), }, { .version = XTABLES_VERSION, .name = "hashlimit", .revision = 1, .family = NFPROTO_IPV4, .size = XT_ALIGN(sizeof(struct xt_hashlimit_mtinfo1)), .userspacesize = offsetof(struct xt_hashlimit_mtinfo1, hinfo), .help = hashlimit_mt_help, .init = hashlimit_mt4_init, .x6_parse = hashlimit_mt_parse, .x6_fcheck = hashlimit_mt_check, .print = hashlimit_mt4_print, .save = hashlimit_mt4_save, .x6_options = hashlimit_mt_opts, .udata_size = sizeof(struct hashlimit_mt_udata), }, { .version = XTABLES_VERSION, .name = "hashlimit", .revision = 1, .family = NFPROTO_IPV6, .size = XT_ALIGN(sizeof(struct xt_hashlimit_mtinfo1)), .userspacesize = offsetof(struct xt_hashlimit_mtinfo1, hinfo), .help = hashlimit_mt_help, .init = hashlimit_mt6_init, .x6_parse = hashlimit_mt_parse, .x6_fcheck = hashlimit_mt_check, .print = hashlimit_mt6_print, .save = hashlimit_mt6_save, .x6_options = hashlimit_mt_opts, .udata_size = sizeof(struct hashlimit_mt_udata), }, }; void _init(void) { xtables_register_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg)); }