--- /dev/null
+/* iptables 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)
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <iptables.h>
+#include <stddef.h>
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_ipv4/ipt_hashlimit.h>
+
+#define IPT_HASHLIMIT_BURST 5
+
+/* miliseconds */
+#define IPT_HASHLIMIT_GCINTERVAL 1000
+#define IPT_HASHLIMIT_EXPIRE 10000
+
+/* Function which prints out usage message. */
+static void
+help(void)
+{
+ printf(
+"hashlimit v%s 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"
+"\n", IPTABLES_VERSION, IPT_HASHLIMIT_BURST);
+}
+
+static struct option opts[] = {
+ { "hashlimit", 1, 0, '%' },
+ { "hashlimit-burst", 1, 0, '$' },
+ { "hashlimit-htable-size", 1, 0, '&' },
+ { "hashlimit-htable-max", 1, 0, '*' },
+ { "hashlimit-htable-gcinterval", 1, 0, '(' },
+ { "hashlimit-htable-expire", 1, 0, ')' },
+ { "hashlimit-mode", 1, 0, '_' },
+ { "hashlimit-name", 1, 0, '"' },
+ { 0 }
+};
+
+static
+int parse_rate(const char *rate, u_int32_t *val)
+{
+ const char *delim;
+ u_int32_t r;
+ u_int32_t 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)
+ mult = 1;
+ else if (strncasecmp(delim+1, "minute", strlen(delim+1)) == 0)
+ mult = 60;
+ else if (strncasecmp(delim+1, "hour", strlen(delim+1)) == 0)
+ mult = 60*60;
+ else if (strncasecmp(delim+1, "day", strlen(delim+1)) == 0)
+ mult = 24*60*60;
+ else
+ return 0;
+ }
+ r = atoi(rate);
+ if (!r)
+ return 0;
+
+ /* This would get mapped to infinite (1/day is minimum they
+ can specify, so we're ok at that end). */
+ if (r / mult > IPT_HASHLIMIT_SCALE)
+ exit_error(PARAMETER_PROBLEM, "Rate too fast `%s'\n", rate);
+
+ *val = IPT_HASHLIMIT_SCALE * mult / r;
+ return 1;
+}
+
+/* Initialize the match. */
+static void
+init(struct ipt_entry_match *m, unsigned int *nfcache)
+{
+ struct ipt_hashlimit_info *r = (struct ipt_hashlimit_info *)m->data;
+
+ r->cfg.burst = IPT_HASHLIMIT_BURST;
+ r->cfg.gc_interval = IPT_HASHLIMIT_GCINTERVAL;
+ r->cfg.expire = IPT_HASHLIMIT_EXPIRE;
+
+}
+
+
+/* Parse a 'mode' parameter into the required bitmask */
+static int parse_mode(struct ipt_hashlimit_info *r, char *optarg)
+{
+ char *tok;
+ char *arg = strdup(optarg);
+
+ if (!arg)
+ return -1;
+
+ r->cfg.mode = 0;
+
+ for (tok = strtok(arg, ",|");
+ tok;
+ tok = strtok(NULL, ",|")) {
+ if (!strcmp(tok, "dstip"))
+ r->cfg.mode |= IPT_HASHLIMIT_HASH_DIP;
+ else if (!strcmp(tok, "srcip"))
+ r->cfg.mode |= IPT_HASHLIMIT_HASH_SIP;
+ else if (!strcmp(tok, "srcport"))
+ r->cfg.mode |= IPT_HASHLIMIT_HASH_SPT;
+ else if (!strcmp(tok, "dstport"))
+ r->cfg.mode |= IPT_HASHLIMIT_HASH_DPT;
+ else {
+ free(arg);
+ return -1;
+ }
+ }
+ free(arg);
+ return 0;
+}
+
+#define PARAM_LIMIT 0x00000001
+#define PARAM_BURST 0x00000002
+#define PARAM_MODE 0x00000004
+#define PARAM_NAME 0x00000008
+#define PARAM_SIZE 0x00000010
+#define PARAM_MAX 0x00000020
+#define PARAM_GCINTERVAL 0x00000040
+#define PARAM_EXPIRE 0x00000080
+
+/* Function which parses command options; returns true if it
+ ate an option */
+static int
+parse(int c, char **argv, int invert, unsigned int *flags,
+ const struct ipt_entry *entry,
+ unsigned int *nfcache,
+ struct ipt_entry_match **match)
+{
+ struct ipt_hashlimit_info *r =
+ (struct ipt_hashlimit_info *)(*match)->data;
+ unsigned int num;
+
+ switch(c) {
+ case '%':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (!parse_rate(optarg, &r->cfg.avg))
+ exit_error(PARAMETER_PROBLEM,
+ "bad rate `%s'", optarg);
+ *flags |= PARAM_LIMIT;
+ break;
+
+ case '$':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (string_to_number(optarg, 0, 10000, &num) == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "bad --hashlimit-burst `%s'", optarg);
+ r->cfg.burst = num;
+ *flags |= PARAM_BURST;
+ break;
+ case '&':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (string_to_number(optarg, 0, 0xffffffff, &num) == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "bad --hashlimit-htable-size: `%s'", optarg);
+ r->cfg.size = num;
+ *flags |= PARAM_SIZE;
+ break;
+ case '*':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (string_to_number(optarg, 0, 0xffffffff, &num) == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "bad --hashlimit-htable-max: `%s'", optarg);
+ r->cfg.max = num;
+ *flags |= PARAM_MAX;
+ break;
+ case '(':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (string_to_number(optarg, 0, 0xffffffff, &num) == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "bad --hashlimit-htable-gcinterval: `%s'",
+ optarg);
+ /* FIXME: not HZ dependent!! */
+ r->cfg.gc_interval = num;
+ *flags |= PARAM_GCINTERVAL;
+ break;
+ case ')':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (string_to_number(optarg, 0, 0xffffffff, &num) == -1)
+ exit_error(PARAMETER_PROBLEM,
+ "bad --hashlimit-htable-expire: `%s'", optarg);
+ /* FIXME: not HZ dependent */
+ r->cfg.expire = num;
+ *flags |= PARAM_EXPIRE;
+ break;
+ case '_':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (parse_mode(r, optarg) < 0)
+ exit_error(PARAMETER_PROBLEM,
+ "bad --hashlimit-mode: `%s'\n", optarg);
+ *flags |= PARAM_MODE;
+ break;
+ case '"':
+ if (check_inverse(argv[optind-1], &invert, &optind, 0)) break;
+ if (strlen(optarg) == 0)
+ exit_error(PARAMETER_PROBLEM, "Zero-length name?");
+ strncpy(r->name, optarg, sizeof(r->name));
+ *flags |= PARAM_NAME;
+ break;
+ default:
+ return 0;
+ }
+
+ if (invert)
+ exit_error(PARAMETER_PROBLEM,
+ "hashlimit does not support invert");
+
+ return 1;
+}
+
+/* Final check; nothing. */
+static void final_check(unsigned int flags)
+{
+ if (!(flags & PARAM_LIMIT))
+ exit_error(PARAMETER_PROBLEM,
+ "You have to specify --hashlimit");
+ if (!(flags & PARAM_MODE))
+ exit_error(PARAMETER_PROBLEM,
+ "You have to specify --hashlimit-mode");
+ if (!(flags & PARAM_NAME))
+ exit_error(PARAMETER_PROBLEM,
+ "You have to specify --hashlimit-name");
+}
+
+static struct rates
+{
+ const char *name;
+ u_int32_t mult;
+} rates[] = { { "day", IPT_HASHLIMIT_SCALE*24*60*60 },
+ { "hour", IPT_HASHLIMIT_SCALE*60*60 },
+ { "min", IPT_HASHLIMIT_SCALE*60 },
+ { "sec", IPT_HASHLIMIT_SCALE } };
+
+static void print_rate(u_int32_t period)
+{
+ unsigned int i;
+
+ for (i = 1; i < sizeof(rates)/sizeof(struct 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);
+}
+
+static void print_mode(const struct ipt_hashlimit_info *r, char separator)
+{
+ int prevmode = 0;
+
+ if (r->cfg.mode & IPT_HASHLIMIT_HASH_SIP) {
+ if (prevmode)
+ putchar(separator);
+ fputs("srcip", stdout);
+ prevmode = 1;
+ }
+ if (r->cfg.mode & IPT_HASHLIMIT_HASH_SPT) {
+ if (prevmode)
+ putchar(separator);
+ fputs("srcport", stdout);
+ prevmode = 1;
+ }
+ if (r->cfg.mode & IPT_HASHLIMIT_HASH_DIP) {
+ if (prevmode)
+ putchar(separator);
+ fputs("dstip", stdout);
+ prevmode = 1;
+ }
+ if (r->cfg.mode & IPT_HASHLIMIT_HASH_DPT) {
+ if (prevmode)
+ putchar(separator);
+ fputs("dstport", stdout);
+ }
+ putchar(' ');
+}
+
+/* Prints out the matchinfo. */
+static void
+print(const struct ipt_ip *ip,
+ const struct ipt_entry_match *match,
+ int numeric)
+{
+ struct ipt_hashlimit_info *r =
+ (struct ipt_hashlimit_info *)match->data;
+ fputs("limit: avg ", stdout); print_rate(r->cfg.avg);
+ printf("burst %u ", r->cfg.burst);
+ fputs("mode ", stdout);
+ print_mode(r, '-');
+ 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 != IPT_HASHLIMIT_GCINTERVAL)
+ printf("htable-gcinterval %u ", r->cfg.gc_interval);
+ if (r->cfg.expire != IPT_HASHLIMIT_EXPIRE)
+ printf("htable-expire %u ", r->cfg.expire);
+}
+
+/* FIXME: Make minimalist: only print rate if not default --RR */
+static void save(const struct ipt_ip *ip, const struct ipt_entry_match *match)
+{
+ struct ipt_hashlimit_info *r =
+ (struct ipt_hashlimit_info *)match->data;
+
+ fputs("--hashlimit ", stdout); print_rate(r->cfg.avg);
+ if (r->cfg.burst != IPT_HASHLIMIT_BURST)
+ printf("--hashlimit-burst %u ", r->cfg.burst);
+
+ fputs("--hashlimit-mode ", stdout);
+ print_mode(r, ',');
+
+ 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 != IPT_HASHLIMIT_GCINTERVAL)
+ printf("--hashlimit-htable-gcinterval %u", r->cfg.gc_interval);
+ if (r->cfg.expire != IPT_HASHLIMIT_EXPIRE)
+ printf("--hashlimit-htable-expire %u ", r->cfg.expire);
+}
+
+static struct iptables_match hashlimit = { NULL,
+ .name = "hashlimit",
+ .version = IPTABLES_VERSION,
+ .size = IPT_ALIGN(sizeof(struct ipt_hashlimit_info)),
+ .userspacesize = offsetof(struct ipt_hashlimit_info, hinfo),
+ .help = &help,
+ .init = &init,
+ .parse = &parse,
+ .final_check = &final_check,
+ .print = &print,
+ .save = &save,
+ .extra_opts = opts
+};
+
+void _init(void)
+{
+ register_match(&hashlimit);
+}
git://git.onelab.eu / iptables.git / blobdiff