-/*
- * Copyright (c) 2006 Patrick McHardy <kaber@trash.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This is a replacement of the old ipt_recent module, which carried the
- * following copyright notice:
- *
- * Author: Stephen Frost <sfrost@snowman.net>
- * Copyright 2002-2003, Stephen Frost, 2.5.x port by laforge@netfilter.org
- */
-#include <linux/init.h>
-#include <linux/moduleparam.h>
+/* Kernel module to check if the source address has been seen recently. */
+/* Copyright 2002-2003, Stephen Frost, 2.5.x port by laforge@netfilter.org */
+/* Author: Stephen Frost <sfrost@snowman.net> */
+/* Project Page: http://snowman.net/projects/ipt_recent/ */
+/* This software is distributed under the terms of the GPL, Version 2 */
+/* This copyright does not cover user programs that use kernel services
+ * by normal system calls. */
+
+#include <linux/module.h>
+#include <linux/skbuff.h>
#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <asm/uaccess.h>
#include <linux/ctype.h>
-#include <linux/list.h>
-#include <linux/random.h>
-#include <linux/jhash.h>
-#include <linux/bitops.h>
-#include <linux/skbuff.h>
-#include <linux/inet.h>
+#include <linux/ip.h>
+#include <linux/vmalloc.h>
+#include <linux/moduleparam.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_recent.h>
-MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
-MODULE_DESCRIPTION("IP tables recently seen matching module");
-MODULE_LICENSE("GPL");
+#undef DEBUG
+#define HASH_LOG 9
+/* Defaults, these can be overridden on the module command-line. */
static unsigned int ip_list_tot = 100;
static unsigned int ip_pkt_list_tot = 20;
static unsigned int ip_list_hash_size = 0;
static unsigned int ip_list_perms = 0644;
+#ifdef DEBUG
+static int debug = 1;
+#endif
+
+static char version[] =
+KERN_INFO RECENT_NAME " " RECENT_VER ": Stephen Frost <sfrost@snowman.net>. http://snowman.net/projects/ipt_recent/\n";
+
+MODULE_AUTHOR("Stephen Frost <sfrost@snowman.net>");
+MODULE_DESCRIPTION("IP tables recently seen matching module " RECENT_VER);
+MODULE_LICENSE("GPL");
module_param(ip_list_tot, uint, 0400);
module_param(ip_pkt_list_tot, uint, 0400);
module_param(ip_list_hash_size, uint, 0400);
module_param(ip_list_perms, uint, 0400);
-MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list");
-MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP to remember (max. 255)");
-MODULE_PARM_DESC(ip_list_hash_size, "size of hash table used to look up IPs");
-MODULE_PARM_DESC(ip_list_perms, "permissions on /proc/net/ipt_recent/* files");
-
-
-struct recent_entry {
- struct list_head list;
- struct list_head lru_list;
- u_int32_t addr;
- u_int8_t ttl;
- u_int8_t index;
- u_int16_t nstamps;
- unsigned long stamps[0];
+#ifdef DEBUG
+module_param(debug, bool, 0600);
+MODULE_PARM_DESC(debug,"enable debugging output");
+#endif
+MODULE_PARM_DESC(ip_list_tot,"number of IPs to remember per list");
+MODULE_PARM_DESC(ip_pkt_list_tot,"number of packets per IP to remember");
+MODULE_PARM_DESC(ip_list_hash_size,"size of hash table used to look up IPs");
+MODULE_PARM_DESC(ip_list_perms,"permissions on /proc/net/ipt_recent/* files");
+
+/* Structure of our list of recently seen addresses. */
+struct recent_ip_list {
+ u_int32_t addr;
+ u_int8_t ttl;
+ unsigned long last_seen;
+ unsigned long *last_pkts;
+ u_int32_t oldest_pkt;
+ u_int32_t hash_entry;
+ u_int32_t time_pos;
+};
+
+struct time_info_list {
+ u_int32_t position;
+ u_int32_t time;
};
-struct recent_table {
- struct list_head list;
- char name[IPT_RECENT_NAME_LEN];
+/* Structure of our linked list of tables of recent lists. */
+struct recent_ip_tables {
+ char name[IPT_RECENT_NAME_LEN];
+ int count;
+ int time_pos;
+ struct recent_ip_list *table;
+ struct recent_ip_tables *next;
+ spinlock_t list_lock;
+ int *hash_table;
+ struct time_info_list *time_info;
#ifdef CONFIG_PROC_FS
- struct proc_dir_entry *proc;
-#endif
- unsigned int refcnt;
- unsigned int entries;
- struct list_head lru_list;
- struct list_head iphash[0];
+ struct proc_dir_entry *status_proc;
+#endif /* CONFIG_PROC_FS */
};
-static LIST_HEAD(tables);
+/* Our current list of addresses we have recently seen.
+ * Only added to on a --set, and only updated on --set || --update
+ */
+static struct recent_ip_tables *r_tables = NULL;
+
+/* We protect r_list with this spinlock so two processors are not modifying
+ * the list at the same time.
+ */
static DEFINE_SPINLOCK(recent_lock);
-static DEFINE_MUTEX(recent_mutex);
#ifdef CONFIG_PROC_FS
-static struct proc_dir_entry *proc_dir;
-static struct file_operations recent_fops;
+/* Our /proc/net/ipt_recent entry */
+static struct proc_dir_entry *proc_net_ipt_recent = NULL;
#endif
-static u_int32_t hash_rnd;
-static int hash_rnd_initted;
-
-static unsigned int recent_entry_hash(u_int32_t addr)
+/* Function declaration for later. */
+static int
+match(const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ const void *matchinfo,
+ int offset,
+ unsigned int protoff,
+ int *hotdrop);
+
+/* Function to hash a given address into the hash table of table_size size */
+static int hash_func(unsigned int addr, int table_size)
{
- if (!hash_rnd_initted) {
- get_random_bytes(&hash_rnd, 4);
- hash_rnd_initted = 1;
- }
- return jhash_1word(addr, hash_rnd) & (ip_list_hash_size - 1);
-}
+ int result = 0;
+ unsigned int value = addr;
+ do { result ^= value; } while((value >>= HASH_LOG));
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": %d = hash_func(%u,%d)\n",
+ result & (table_size - 1),
+ addr,
+ table_size);
+#endif
-static struct recent_entry *
-recent_entry_lookup(const struct recent_table *table, u_int32_t addr, u_int8_t ttl)
-{
- struct recent_entry *e;
- unsigned int h;
-
- h = recent_entry_hash(addr);
- list_for_each_entry(e, &table->iphash[h], list)
- if (e->addr == addr && (ttl == e->ttl || !ttl || !e->ttl))
- return e;
- return NULL;
+ return(result & (table_size - 1));
}
-static void recent_entry_remove(struct recent_table *t, struct recent_entry *e)
+#ifdef CONFIG_PROC_FS
+/* This is the function which produces the output for our /proc output
+ * interface which lists each IP address, the last seen time and the
+ * other recent times the address was seen.
+ */
+
+static int ip_recent_get_info(char *buffer, char **start, off_t offset, int length, int *eof, void *data)
{
- list_del(&e->list);
- list_del(&e->lru_list);
- kfree(e);
- t->entries--;
+ int len = 0, count, last_len = 0, pkt_count;
+ off_t pos = 0;
+ off_t begin = 0;
+ struct recent_ip_tables *curr_table;
+
+ curr_table = (struct recent_ip_tables*) data;
+
+ spin_lock_bh(&curr_table->list_lock);
+ for(count = 0; count < ip_list_tot; count++) {
+ if(!curr_table->table[count].addr) continue;
+ last_len = len;
+ len += sprintf(buffer+len,"src=%u.%u.%u.%u ",NIPQUAD(curr_table->table[count].addr));
+ len += sprintf(buffer+len,"ttl: %u ",curr_table->table[count].ttl);
+ len += sprintf(buffer+len,"last_seen: %lu ",curr_table->table[count].last_seen);
+ len += sprintf(buffer+len,"oldest_pkt: %u ",curr_table->table[count].oldest_pkt);
+ len += sprintf(buffer+len,"last_pkts: %lu",curr_table->table[count].last_pkts[0]);
+ for(pkt_count = 1; pkt_count < ip_pkt_list_tot; pkt_count++) {
+ if(!curr_table->table[count].last_pkts[pkt_count]) break;
+ len += sprintf(buffer+len,", %lu",curr_table->table[count].last_pkts[pkt_count]);
+ }
+ len += sprintf(buffer+len,"\n");
+ pos = begin + len;
+ if(pos < offset) { len = 0; begin = pos; }
+ if(pos > offset + length) { len = last_len; break; }
+ }
+
+ *start = buffer + (offset - begin);
+ len -= (offset - begin);
+ if(len > length) len = length;
+
+ spin_unlock_bh(&curr_table->list_lock);
+ return len;
}
-static struct recent_entry *
-recent_entry_init(struct recent_table *t, u_int32_t addr, u_int8_t ttl)
+/* ip_recent_ctrl provides an interface for users to modify the table
+ * directly. This allows adding entries, removing entries, and
+ * flushing the entire table.
+ * This is done by opening up the appropriate table for writing and
+ * sending one of:
+ * xx.xx.xx.xx -- Add entry to table with current time
+ * +xx.xx.xx.xx -- Add entry to table with current time
+ * -xx.xx.xx.xx -- Remove entry from table
+ * clear -- Flush table, remove all entries
+ */
+
+static int ip_recent_ctrl(struct file *file, const char __user *input, unsigned long size, void *data)
{
- struct recent_entry *e;
+ static const u_int32_t max[4] = { 0xffffffff, 0xffffff, 0xffff, 0xff };
+ u_int32_t val;
+ int base, used = 0;
+ char c, *cp;
+ union iaddr {
+ uint8_t bytes[4];
+ uint32_t word;
+ } res;
+ uint8_t *pp = res.bytes;
+ int digit;
+
+ char buffer[20];
+ int len, check_set = 0, count;
+ u_int32_t addr = 0;
+ struct sk_buff *skb;
+ struct ipt_recent_info *info;
+ struct recent_ip_tables *curr_table;
+
+ curr_table = (struct recent_ip_tables*) data;
+
+ if(size > 20) len = 20; else len = size;
+
+ if(copy_from_user(buffer,input,len)) return -EFAULT;
+
+ if(len < 20) buffer[len] = '\0';
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": ip_recent_ctrl len: %d, input: `%.20s'\n",len,buffer);
+#endif
- if (t->entries >= ip_list_tot) {
- e = list_entry(t->lru_list.next, struct recent_entry, lru_list);
- recent_entry_remove(t, e);
+ cp = buffer;
+ while(isspace(*cp)) { cp++; used++; if(used >= len-5) return used; }
+
+ /* Check if we are asked to flush the entire table */
+ if(!memcmp(cp,"clear",5)) {
+ used += 5;
+ spin_lock_bh(&curr_table->list_lock);
+ curr_table->time_pos = 0;
+ for(count = 0; count < ip_list_hash_size; count++) {
+ curr_table->hash_table[count] = -1;
+ }
+ for(count = 0; count < ip_list_tot; count++) {
+ curr_table->table[count].last_seen = 0;
+ curr_table->table[count].addr = 0;
+ curr_table->table[count].ttl = 0;
+ memset(curr_table->table[count].last_pkts,0,ip_pkt_list_tot*sizeof(unsigned long));
+ curr_table->table[count].oldest_pkt = 0;
+ curr_table->table[count].time_pos = 0;
+ curr_table->time_info[count].position = count;
+ curr_table->time_info[count].time = 0;
+ }
+ spin_unlock_bh(&curr_table->list_lock);
+ return used;
}
- e = kmalloc(sizeof(*e) + sizeof(e->stamps[0]) * ip_pkt_list_tot,
- GFP_ATOMIC);
- if (e == NULL)
- return NULL;
- e->addr = addr;
- e->ttl = ttl;
- e->stamps[0] = jiffies;
- e->nstamps = 1;
- e->index = 1;
- list_add_tail(&e->list, &t->iphash[recent_entry_hash(addr)]);
- list_add_tail(&e->lru_list, &t->lru_list);
- t->entries++;
- return e;
-}
-static void recent_entry_update(struct recent_table *t, struct recent_entry *e)
-{
- e->stamps[e->index++] = jiffies;
- if (e->index > e->nstamps)
- e->nstamps = e->index;
- e->index %= ip_pkt_list_tot;
- list_move_tail(&e->lru_list, &t->lru_list);
-}
+ check_set = IPT_RECENT_SET;
+ switch(*cp) {
+ case '+': check_set = IPT_RECENT_SET; cp++; used++; break;
+ case '-': check_set = IPT_RECENT_REMOVE; cp++; used++; break;
+ default: if(!isdigit(*cp)) return (used+1); break;
+ }
-static struct recent_table *recent_table_lookup(const char *name)
-{
- struct recent_table *t;
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": ip_recent_ctrl cp: `%c', check_set: %d\n",*cp,check_set);
+#endif
+ /* Get addr (effectively inet_aton()) */
+ /* Shamelessly stolen from libc, a function in the kernel for doing
+ * this would, of course, be greatly preferred, but our options appear
+ * to be rather limited, so we will just do it ourselves here.
+ */
+ res.word = 0;
+
+ c = *cp;
+ for(;;) {
+ if(!isdigit(c)) return used;
+ val = 0; base = 10; digit = 0;
+ if(c == '0') {
+ c = *++cp;
+ if(c == 'x' || c == 'X') base = 16, c = *++cp;
+ else { base = 8; digit = 1; }
+ }
+ for(;;) {
+ if(isascii(c) && isdigit(c)) {
+ if(base == 8 && (c == '8' || c == '0')) return used;
+ val = (val * base) + (c - '0');
+ c = *++cp;
+ digit = 1;
+ } else if(base == 16 && isascii(c) && isxdigit(c)) {
+ val = (val << 4) | (c + 10 - (islower(c) ? 'a' : 'A'));
+ c = *++cp;
+ digit = 1;
+ } else break;
+ }
+ if(c == '.') {
+ if(pp > res.bytes + 2 || val > 0xff) return used;
+ *pp++ = val;
+ c = *++cp;
+ } else break;
+ }
+ used = cp - buffer;
+ if(c != '\0' && (!isascii(c) || !isspace(c))) return used;
+ if(c == '\n') used++;
+ if(!digit) return used;
- list_for_each_entry(t, &tables, list)
- if (!strcmp(t->name, name))
- return t;
- return NULL;
-}
+ if(val > max[pp - res.bytes]) return used;
+ addr = res.word | htonl(val);
-static void recent_table_flush(struct recent_table *t)
-{
- struct recent_entry *e, *next;
- unsigned int i;
+ if(!addr && check_set == IPT_RECENT_SET) return used;
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": ip_recent_ctrl c: %c, addr: %u used: %d\n",c,addr,used);
+#endif
- for (i = 0; i < ip_list_hash_size; i++) {
- list_for_each_entry_safe(e, next, &t->iphash[i], list)
- recent_entry_remove(t, e);
+ /* Set up and just call match */
+ info = kmalloc(sizeof(struct ipt_recent_info),GFP_KERNEL);
+ if(!info) { return -ENOMEM; }
+ info->seconds = 0;
+ info->hit_count = 0;
+ info->check_set = check_set;
+ info->invert = 0;
+ info->side = IPT_RECENT_SOURCE;
+ strncpy(info->name,curr_table->name,IPT_RECENT_NAME_LEN);
+ info->name[IPT_RECENT_NAME_LEN-1] = '\0';
+
+ skb = kmalloc(sizeof(struct sk_buff),GFP_KERNEL);
+ if (!skb) {
+ used = -ENOMEM;
+ goto out_free_info;
}
+ skb->nh.iph = kmalloc(sizeof(struct iphdr),GFP_KERNEL);
+ if (!skb->nh.iph) {
+ used = -ENOMEM;
+ goto out_free_skb;
+ }
+
+ skb->nh.iph->saddr = addr;
+ skb->nh.iph->daddr = 0;
+ /* Clear ttl since we have no way of knowing it */
+ skb->nh.iph->ttl = 0;
+ match(skb,NULL,NULL,info,0,0,NULL);
+
+ kfree(skb->nh.iph);
+out_free_skb:
+ kfree(skb);
+out_free_info:
+ kfree(info);
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": Leaving ip_recent_ctrl addr: %u used: %d\n",addr,used);
+#endif
+ return used;
}
+#endif /* CONFIG_PROC_FS */
+
+/* 'match' is our primary function, called by the kernel whenever a rule is
+ * hit with our module as an option to it.
+ * What this function does depends on what was specifically asked of it by
+ * the user:
+ * --set -- Add or update last seen time of the source address of the packet
+ * -- matchinfo->check_set == IPT_RECENT_SET
+ * --rcheck -- Just check if the source address is in the list
+ * -- matchinfo->check_set == IPT_RECENT_CHECK
+ * --update -- If the source address is in the list, update last_seen
+ * -- matchinfo->check_set == IPT_RECENT_UPDATE
+ * --remove -- If the source address is in the list, remove it
+ * -- matchinfo->check_set == IPT_RECENT_REMOVE
+ * --seconds -- Option to --rcheck/--update, only match if last_seen within seconds
+ * -- matchinfo->seconds
+ * --hitcount -- Option to --rcheck/--update, only match if seen hitcount times
+ * -- matchinfo->hit_count
+ * --seconds and --hitcount can be combined
+ */
static int
-ipt_recent_match(const struct sk_buff *skb,
- const struct net_device *in, const struct net_device *out,
- const struct xt_match *match, const void *matchinfo,
- int offset, unsigned int protoff, int *hotdrop)
+match(const struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ const void *matchinfo,
+ int offset,
+ unsigned int protoff,
+ int *hotdrop)
{
+ int pkt_count, hits_found, ans;
+ unsigned long now;
const struct ipt_recent_info *info = matchinfo;
- struct recent_table *t;
- struct recent_entry *e;
- u_int32_t addr;
- u_int8_t ttl;
- int ret = info->invert;
+ u_int32_t addr = 0, time_temp;
+ u_int8_t ttl = skb->nh.iph->ttl;
+ int *hash_table;
+ int orig_hash_result, hash_result, temp, location = 0, time_loc, end_collision_chain = -1;
+ struct time_info_list *time_info;
+ struct recent_ip_tables *curr_table;
+ struct recent_ip_tables *last_table;
+ struct recent_ip_list *r_list;
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match() called\n");
+#endif
+
+ /* Default is false ^ info->invert */
+ ans = info->invert;
- if (info->side == IPT_RECENT_DEST)
- addr = skb->nh.iph->daddr;
- else
- addr = skb->nh.iph->saddr;
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): name = '%s'\n",info->name);
+#endif
- ttl = skb->nh.iph->ttl;
- /* use TTL as seen before forwarding */
- if (out && !skb->sk)
- ttl++;
+ /* if out != NULL then routing has been done and TTL changed.
+ * We change it back here internally for match what came in before routing. */
+ if(out) ttl++;
+ /* Find the right table */
spin_lock_bh(&recent_lock);
- t = recent_table_lookup(info->name);
- e = recent_entry_lookup(t, addr,
- info->check_set & IPT_RECENT_TTL ? ttl : 0);
- if (e == NULL) {
- if (!(info->check_set & IPT_RECENT_SET))
- goto out;
- e = recent_entry_init(t, addr, ttl);
- if (e == NULL)
- *hotdrop = 1;
- ret ^= 1;
- goto out;
+ curr_table = r_tables;
+ while( (last_table = curr_table) && strncmp(info->name,curr_table->name,IPT_RECENT_NAME_LEN) && (curr_table = curr_table->next) );
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): table found('%s')\n",info->name);
+#endif
+
+ spin_unlock_bh(&recent_lock);
+
+ /* Table with this name not found, match impossible */
+ if(!curr_table) { return ans; }
+
+ /* Make sure no one is changing the list while we work with it */
+ spin_lock_bh(&curr_table->list_lock);
+
+ r_list = curr_table->table;
+ if(info->side == IPT_RECENT_DEST) addr = skb->nh.iph->daddr; else addr = skb->nh.iph->saddr;
+
+ if(!addr) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match() address (%u) invalid, leaving.\n",addr);
+#endif
+ spin_unlock_bh(&curr_table->list_lock);
+ return ans;
}
- if (info->check_set & IPT_RECENT_SET)
- ret ^= 1;
- else if (info->check_set & IPT_RECENT_REMOVE) {
- recent_entry_remove(t, e);
- ret ^= 1;
- } else if (info->check_set & (IPT_RECENT_CHECK | IPT_RECENT_UPDATE)) {
- unsigned long t = jiffies - info->seconds * HZ;
- unsigned int i, hits = 0;
-
- for (i = 0; i < e->nstamps; i++) {
- if (info->seconds && time_after(t, e->stamps[i]))
- continue;
- if (++hits >= info->hit_count) {
- ret ^= 1;
- break;
- }
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): checking table, addr: %u, ttl: %u, orig_ttl: %u\n",addr,ttl,skb->nh.iph->ttl);
+#endif
+
+ /* Get jiffies now in case they changed while we were waiting for a lock */
+ now = jiffies;
+ hash_table = curr_table->hash_table;
+ time_info = curr_table->time_info;
+
+ orig_hash_result = hash_result = hash_func(addr,ip_list_hash_size);
+ /* Hash entry at this result used */
+ /* Check for TTL match if requested. If TTL is zero then a match would never
+ * happen, so match regardless of existing TTL in that case. Zero means the
+ * entry was added via the /proc interface anyway, so we will just use the
+ * first TTL we get for that IP address. */
+ if(info->check_set & IPT_RECENT_TTL) {
+ while(hash_table[hash_result] != -1 && !(r_list[hash_table[hash_result]].addr == addr &&
+ (!r_list[hash_table[hash_result]].ttl || r_list[hash_table[hash_result]].ttl == ttl))) {
+ /* Collision in hash table */
+ hash_result = (hash_result + 1) % ip_list_hash_size;
+ }
+ } else {
+ while(hash_table[hash_result] != -1 && r_list[hash_table[hash_result]].addr != addr) {
+ /* Collision in hash table */
+ hash_result = (hash_result + 1) % ip_list_hash_size;
}
}
- if (info->check_set & IPT_RECENT_SET ||
- (info->check_set & IPT_RECENT_UPDATE && ret)) {
- recent_entry_update(t, e);
- e->ttl = ttl;
+ if(hash_table[hash_result] == -1 && !(info->check_set & IPT_RECENT_SET)) {
+ /* IP not in list and not asked to SET */
+ spin_unlock_bh(&curr_table->list_lock);
+ return ans;
}
-out:
- spin_unlock_bh(&recent_lock);
- return ret;
-}
-static int
-ipt_recent_checkentry(const char *tablename, const void *ip,
- const struct xt_match *match, void *matchinfo,
- unsigned int matchsize, unsigned int hook_mask)
-{
- const struct ipt_recent_info *info = matchinfo;
- struct recent_table *t;
- unsigned i;
- int ret = 0;
+ /* Check if we need to handle the collision, do not need to on REMOVE */
+ if(orig_hash_result != hash_result && !(info->check_set & IPT_RECENT_REMOVE)) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): Collision in hash table. (or: %d,hr: %d,oa: %u,ha: %u)\n",
+ orig_hash_result,
+ hash_result,
+ r_list[hash_table[orig_hash_result]].addr,
+ addr);
+#endif
- if (hweight8(info->check_set &
- (IPT_RECENT_SET | IPT_RECENT_REMOVE |
- IPT_RECENT_CHECK | IPT_RECENT_UPDATE)) != 1)
- return 0;
- if ((info->check_set & (IPT_RECENT_SET | IPT_RECENT_REMOVE)) &&
- (info->seconds || info->hit_count))
- return 0;
- if (info->name[0] == '\0' ||
- strnlen(info->name, IPT_RECENT_NAME_LEN) == IPT_RECENT_NAME_LEN)
- return 0;
+ /* We had a collision.
+ * orig_hash_result is where we started, hash_result is where we ended up.
+ * So, swap them because we are likely to see the same guy again sooner */
+#ifdef DEBUG
+ if(debug) {
+ printk(KERN_INFO RECENT_NAME ": match(): Collision; hash_table[orig_hash_result] = %d\n",hash_table[orig_hash_result]);
+ printk(KERN_INFO RECENT_NAME ": match(): Collision; r_list[hash_table[orig_hash_result]].hash_entry = %d\n",
+ r_list[hash_table[orig_hash_result]].hash_entry);
+ }
+#endif
+
+ r_list[hash_table[orig_hash_result]].hash_entry = hash_result;
+
+
+ temp = hash_table[orig_hash_result];
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): Collision; hash_table[hash_result] = %d\n",hash_table[hash_result]);
+#endif
+ hash_table[orig_hash_result] = hash_table[hash_result];
+ hash_table[hash_result] = temp;
+ temp = hash_result;
+ hash_result = orig_hash_result;
+ orig_hash_result = temp;
+ time_info[r_list[hash_table[orig_hash_result]].time_pos].position = hash_table[orig_hash_result];
+ if(hash_table[hash_result] != -1) {
+ r_list[hash_table[hash_result]].hash_entry = hash_result;
+ time_info[r_list[hash_table[hash_result]].time_pos].position = hash_table[hash_result];
+ }
- mutex_lock(&recent_mutex);
- t = recent_table_lookup(info->name);
- if (t != NULL) {
- t->refcnt++;
- ret = 1;
- goto out;
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): Collision handled.\n");
+#endif
}
- t = kzalloc(sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size,
- GFP_KERNEL);
- if (t == NULL)
- goto out;
- t->refcnt = 1;
- strcpy(t->name, info->name);
- INIT_LIST_HEAD(&t->lru_list);
- for (i = 0; i < ip_list_hash_size; i++)
- INIT_LIST_HEAD(&t->iphash[i]);
-#ifdef CONFIG_PROC_FS
- t->proc = create_proc_entry(t->name, ip_list_perms, proc_dir);
- if (t->proc == NULL) {
- kfree(t);
- goto out;
+ if(hash_table[hash_result] == -1) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): New table entry. (hr: %d,ha: %u)\n",
+ hash_result, addr);
+#endif
+
+ /* New item found and IPT_RECENT_SET, so we need to add it */
+ location = time_info[curr_table->time_pos].position;
+ hash_table[r_list[location].hash_entry] = -1;
+ hash_table[hash_result] = location;
+ memset(r_list[location].last_pkts,0,ip_pkt_list_tot*sizeof(unsigned long));
+ r_list[location].time_pos = curr_table->time_pos;
+ r_list[location].addr = addr;
+ r_list[location].ttl = ttl;
+ r_list[location].last_seen = now;
+ r_list[location].oldest_pkt = 1;
+ r_list[location].last_pkts[0] = now;
+ r_list[location].hash_entry = hash_result;
+ time_info[curr_table->time_pos].time = r_list[location].last_seen;
+ curr_table->time_pos = (curr_table->time_pos + 1) % ip_list_tot;
+
+ ans = !info->invert;
+ } else {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): Existing table entry. (hr: %d,ha: %u)\n",
+ hash_result,
+ addr);
+#endif
+
+ /* Existing item found */
+ location = hash_table[hash_result];
+ /* We have a match on address, now to make sure it meets all requirements for a
+ * full match. */
+ if(info->check_set & IPT_RECENT_CHECK || info->check_set & IPT_RECENT_UPDATE) {
+ if(!info->seconds && !info->hit_count) ans = !info->invert; else ans = info->invert;
+ if(info->seconds && !info->hit_count) {
+ if(time_before_eq(now,r_list[location].last_seen+info->seconds*HZ)) ans = !info->invert; else ans = info->invert;
+ }
+ if(info->seconds && info->hit_count) {
+ for(pkt_count = 0, hits_found = 0; pkt_count < ip_pkt_list_tot; pkt_count++) {
+ if(r_list[location].last_pkts[pkt_count] == 0) break;
+ if(time_before_eq(now,r_list[location].last_pkts[pkt_count]+info->seconds*HZ)) hits_found++;
+ }
+ if(hits_found >= info->hit_count) ans = !info->invert; else ans = info->invert;
+ }
+ if(info->hit_count && !info->seconds) {
+ for(pkt_count = 0, hits_found = 0; pkt_count < ip_pkt_list_tot; pkt_count++) {
+ if(r_list[location].last_pkts[pkt_count] == 0) break;
+ hits_found++;
+ }
+ if(hits_found >= info->hit_count) ans = !info->invert; else ans = info->invert;
+ }
+ }
+#ifdef DEBUG
+ if(debug) {
+ if(ans)
+ printk(KERN_INFO RECENT_NAME ": match(): match addr: %u\n",addr);
+ else
+ printk(KERN_INFO RECENT_NAME ": match(): no match addr: %u\n",addr);
+ }
+#endif
+
+ /* If and only if we have been asked to SET, or to UPDATE (on match) do we add the
+ * current timestamp to the last_seen. */
+ if((info->check_set & IPT_RECENT_SET && (ans = !info->invert)) || (info->check_set & IPT_RECENT_UPDATE && ans)) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): SET or UPDATE; updating time info.\n");
+#endif
+ /* Have to update our time info */
+ time_loc = r_list[location].time_pos;
+ time_info[time_loc].time = now;
+ time_info[time_loc].position = location;
+ while((time_info[(time_loc+1) % ip_list_tot].time < time_info[time_loc].time) && ((time_loc+1) % ip_list_tot) != curr_table->time_pos) {
+ time_temp = time_info[time_loc].time;
+ time_info[time_loc].time = time_info[(time_loc+1)%ip_list_tot].time;
+ time_info[(time_loc+1)%ip_list_tot].time = time_temp;
+ time_temp = time_info[time_loc].position;
+ time_info[time_loc].position = time_info[(time_loc+1)%ip_list_tot].position;
+ time_info[(time_loc+1)%ip_list_tot].position = time_temp;
+ r_list[time_info[time_loc].position].time_pos = time_loc;
+ r_list[time_info[(time_loc+1)%ip_list_tot].position].time_pos = (time_loc+1)%ip_list_tot;
+ time_loc = (time_loc+1) % ip_list_tot;
+ }
+ r_list[location].time_pos = time_loc;
+ r_list[location].ttl = ttl;
+ r_list[location].last_pkts[r_list[location].oldest_pkt] = now;
+ r_list[location].oldest_pkt = ++r_list[location].oldest_pkt % ip_pkt_list_tot;
+ r_list[location].last_seen = now;
+ }
+ /* If we have been asked to remove the entry from the list, just set it to 0 */
+ if(info->check_set & IPT_RECENT_REMOVE) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): REMOVE; clearing entry (or: %d, hr: %d).\n",orig_hash_result,hash_result);
+#endif
+ /* Check if this is part of a collision chain */
+ while(hash_table[(orig_hash_result+1) % ip_list_hash_size] != -1) {
+ orig_hash_result++;
+ if(hash_func(r_list[hash_table[orig_hash_result]].addr,ip_list_hash_size) == hash_result) {
+ /* Found collision chain, how deep does this rabbit hole go? */
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): REMOVE; found collision chain.\n");
+#endif
+ end_collision_chain = orig_hash_result;
+ }
+ }
+ if(end_collision_chain != -1) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match(): REMOVE; part of collision chain, moving to end.\n");
+#endif
+ /* Part of a collision chain, swap it with the end of the chain
+ * before removing. */
+ r_list[hash_table[end_collision_chain]].hash_entry = hash_result;
+ temp = hash_table[end_collision_chain];
+ hash_table[end_collision_chain] = hash_table[hash_result];
+ hash_table[hash_result] = temp;
+ time_info[r_list[hash_table[hash_result]].time_pos].position = hash_table[hash_result];
+ hash_result = end_collision_chain;
+ r_list[hash_table[hash_result]].hash_entry = hash_result;
+ time_info[r_list[hash_table[hash_result]].time_pos].position = hash_table[hash_result];
+ }
+ location = hash_table[hash_result];
+ hash_table[r_list[location].hash_entry] = -1;
+ time_loc = r_list[location].time_pos;
+ time_info[time_loc].time = 0;
+ time_info[time_loc].position = location;
+ while((time_info[(time_loc+1) % ip_list_tot].time < time_info[time_loc].time) && ((time_loc+1) % ip_list_tot) != curr_table->time_pos) {
+ time_temp = time_info[time_loc].time;
+ time_info[time_loc].time = time_info[(time_loc+1)%ip_list_tot].time;
+ time_info[(time_loc+1)%ip_list_tot].time = time_temp;
+ time_temp = time_info[time_loc].position;
+ time_info[time_loc].position = time_info[(time_loc+1)%ip_list_tot].position;
+ time_info[(time_loc+1)%ip_list_tot].position = time_temp;
+ r_list[time_info[time_loc].position].time_pos = time_loc;
+ r_list[time_info[(time_loc+1)%ip_list_tot].position].time_pos = (time_loc+1)%ip_list_tot;
+ time_loc = (time_loc+1) % ip_list_tot;
+ }
+ r_list[location].time_pos = time_loc;
+ r_list[location].last_seen = 0;
+ r_list[location].addr = 0;
+ r_list[location].ttl = 0;
+ memset(r_list[location].last_pkts,0,ip_pkt_list_tot*sizeof(unsigned long));
+ r_list[location].oldest_pkt = 0;
+ ans = !info->invert;
+ }
+ spin_unlock_bh(&curr_table->list_lock);
+ return ans;
}
- t->proc->proc_fops = &recent_fops;
- t->proc->data = t;
+
+ spin_unlock_bh(&curr_table->list_lock);
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": match() left.\n");
#endif
- spin_lock_bh(&recent_lock);
- list_add_tail(&t->list, &tables);
- spin_unlock_bh(&recent_lock);
- ret = 1;
-out:
- mutex_unlock(&recent_mutex);
- return ret;
+ return ans;
}
-static void
-ipt_recent_destroy(const struct xt_match *match, void *matchinfo,
- unsigned int matchsize)
+/* This function is to verify that the rule given during the userspace iptables
+ * command is correct.
+ * If the command is valid then we check if the table name referred to by the
+ * rule exists, if not it is created.
+ */
+static int
+checkentry(const char *tablename,
+ const void *ip,
+ void *matchinfo,
+ unsigned int matchsize,
+ unsigned int hook_mask)
{
+ int flag = 0, c;
+ unsigned long *hold;
const struct ipt_recent_info *info = matchinfo;
- struct recent_table *t;
+ struct recent_ip_tables *curr_table, *find_table, *last_table;
- mutex_lock(&recent_mutex);
- t = recent_table_lookup(info->name);
- if (--t->refcnt == 0) {
- spin_lock_bh(&recent_lock);
- list_del(&t->list);
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry() entered.\n");
+#endif
+
+ if (matchsize != IPT_ALIGN(sizeof(struct ipt_recent_info))) return 0;
+
+ /* seconds and hit_count only valid for CHECK/UPDATE */
+ if(info->check_set & IPT_RECENT_SET) { flag++; if(info->seconds || info->hit_count) return 0; }
+ if(info->check_set & IPT_RECENT_REMOVE) { flag++; if(info->seconds || info->hit_count) return 0; }
+ if(info->check_set & IPT_RECENT_CHECK) flag++;
+ if(info->check_set & IPT_RECENT_UPDATE) flag++;
+
+ /* One and only one of these should ever be set */
+ if(flag != 1) return 0;
+
+ /* Name must be set to something */
+ if(!info->name || !info->name[0]) return 0;
+
+ /* Things look good, create a list for this if it does not exist */
+ /* Lock the linked list while we play with it */
+ spin_lock_bh(&recent_lock);
+
+ /* Look for an entry with this name already created */
+ /* Finds the end of the list and the entry before the end if current name does not exist */
+ find_table = r_tables;
+ while( (last_table = find_table) && strncmp(info->name,find_table->name,IPT_RECENT_NAME_LEN) && (find_table = find_table->next) );
+
+ /* If a table already exists just increment the count on that table and return */
+ if(find_table) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry: table found (%s), incrementing count.\n",info->name);
+#endif
+ find_table->count++;
spin_unlock_bh(&recent_lock);
- recent_table_flush(t);
-#ifdef CONFIG_PROC_FS
- remove_proc_entry(t->name, proc_dir);
+ return 1;
+ }
+
+ spin_unlock_bh(&recent_lock);
+
+ /* Table with this name not found */
+ /* Allocate memory for new linked list item */
+
+#ifdef DEBUG
+ if(debug) {
+ printk(KERN_INFO RECENT_NAME ": checkentry: no table found (%s)\n",info->name);
+ printk(KERN_INFO RECENT_NAME ": checkentry: Allocationg %d for link-list entry.\n",sizeof(struct recent_ip_tables));
+ }
+#endif
+
+ curr_table = vmalloc(sizeof(struct recent_ip_tables));
+ if(curr_table == NULL) return 0;
+
+ spin_lock_init(&curr_table->list_lock);
+ curr_table->next = NULL;
+ curr_table->count = 1;
+ curr_table->time_pos = 0;
+ strncpy(curr_table->name,info->name,IPT_RECENT_NAME_LEN);
+ curr_table->name[IPT_RECENT_NAME_LEN-1] = '\0';
+
+ /* Allocate memory for this table and the list of packets in each entry. */
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry: Allocating %d for table (%s).\n",
+ sizeof(struct recent_ip_list)*ip_list_tot,
+ info->name);
+#endif
+
+ curr_table->table = vmalloc(sizeof(struct recent_ip_list)*ip_list_tot);
+ if(curr_table->table == NULL) { vfree(curr_table); return 0; }
+ memset(curr_table->table,0,sizeof(struct recent_ip_list)*ip_list_tot);
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry: Allocating %d for pkt_list.\n",
+ sizeof(unsigned long)*ip_pkt_list_tot*ip_list_tot);
#endif
- kfree(t);
+
+ hold = vmalloc(sizeof(unsigned long)*ip_pkt_list_tot*ip_list_tot);
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry: After pkt_list allocation.\n");
+#endif
+ if(hold == NULL) {
+ printk(KERN_INFO RECENT_NAME ": checkentry: unable to allocate for pkt_list.\n");
+ vfree(curr_table->table);
+ vfree(curr_table);
+ return 0;
+ }
+ for(c = 0; c < ip_list_tot; c++) {
+ curr_table->table[c].last_pkts = hold + c*ip_pkt_list_tot;
}
- mutex_unlock(&recent_mutex);
-}
-#ifdef CONFIG_PROC_FS
-struct recent_iter_state {
- struct recent_table *table;
- unsigned int bucket;
-};
+ /* Allocate memory for the hash table */
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry: Allocating %d for hash_table.\n",
+ sizeof(int)*ip_list_hash_size);
+#endif
-static void *recent_seq_start(struct seq_file *seq, loff_t *pos)
-{
- struct recent_iter_state *st = seq->private;
- struct recent_table *t = st->table;
- struct recent_entry *e;
- loff_t p = *pos;
+ curr_table->hash_table = vmalloc(sizeof(int)*ip_list_hash_size);
+ if(!curr_table->hash_table) {
+ printk(KERN_INFO RECENT_NAME ": checkentry: unable to allocate for hash_table.\n");
+ vfree(hold);
+ vfree(curr_table->table);
+ vfree(curr_table);
+ return 0;
+ }
- spin_lock_bh(&recent_lock);
+ for(c = 0; c < ip_list_hash_size; c++) {
+ curr_table->hash_table[c] = -1;
+ }
- for (st->bucket = 0; st->bucket < ip_list_hash_size; st->bucket++) {
- list_for_each_entry(e, &t->iphash[st->bucket], list) {
- if (p-- == 0)
- return e;
- }
+ /* Allocate memory for the time info */
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry: Allocating %d for time_info.\n",
+ sizeof(struct time_info_list)*ip_list_tot);
+#endif
+
+ curr_table->time_info = vmalloc(sizeof(struct time_info_list)*ip_list_tot);
+ if(!curr_table->time_info) {
+ printk(KERN_INFO RECENT_NAME ": checkentry: unable to allocate for time_info.\n");
+ vfree(curr_table->hash_table);
+ vfree(hold);
+ vfree(curr_table->table);
+ vfree(curr_table);
+ return 0;
+ }
+ for(c = 0; c < ip_list_tot; c++) {
+ curr_table->time_info[c].position = c;
+ curr_table->time_info[c].time = 0;
}
- return NULL;
-}
-static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos)
-{
- struct recent_iter_state *st = seq->private;
- struct recent_table *t = st->table;
- struct recent_entry *e = v;
- struct list_head *head = e->list.next;
-
- while (head == &t->iphash[st->bucket]) {
- if (++st->bucket >= ip_list_hash_size)
- return NULL;
- head = t->iphash[st->bucket].next;
+ /* Put the new table in place */
+ spin_lock_bh(&recent_lock);
+ find_table = r_tables;
+ while( (last_table = find_table) && strncmp(info->name,find_table->name,IPT_RECENT_NAME_LEN) && (find_table = find_table->next) );
+
+ /* If a table already exists just increment the count on that table and return */
+ if(find_table) {
+ find_table->count++;
+ spin_unlock_bh(&recent_lock);
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry: table found (%s), created by other process.\n",info->name);
+#endif
+ vfree(curr_table->time_info);
+ vfree(curr_table->hash_table);
+ vfree(hold);
+ vfree(curr_table->table);
+ vfree(curr_table);
+ return 1;
}
- (*pos)++;
- return list_entry(head, struct recent_entry, list);
-}
+ if(!last_table) r_tables = curr_table; else last_table->next = curr_table;
-static void recent_seq_stop(struct seq_file *s, void *v)
-{
spin_unlock_bh(&recent_lock);
-}
-static int recent_seq_show(struct seq_file *seq, void *v)
-{
- struct recent_entry *e = v;
- unsigned int i;
-
- i = (e->index - 1) % ip_pkt_list_tot;
- seq_printf(seq, "src=%u.%u.%u.%u ttl: %u last_seen: %lu oldest_pkt: %u",
- NIPQUAD(e->addr), e->ttl, e->stamps[i], e->index);
- for (i = 0; i < e->nstamps; i++)
- seq_printf(seq, "%s %lu", i ? "," : "", e->stamps[i]);
- seq_printf(seq, "\n");
- return 0;
-}
+#ifdef CONFIG_PROC_FS
+ /* Create our proc 'status' entry. */
+ curr_table->status_proc = create_proc_entry(curr_table->name, ip_list_perms, proc_net_ipt_recent);
+ if (!curr_table->status_proc) {
+ printk(KERN_INFO RECENT_NAME ": checkentry: unable to allocate for /proc entry.\n");
+ /* Destroy the created table */
+ spin_lock_bh(&recent_lock);
+ last_table = NULL;
+ curr_table = r_tables;
+ if(!curr_table) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry() create_proc failed, no tables.\n");
+#endif
+ spin_unlock_bh(&recent_lock);
+ return 0;
+ }
+ while( strncmp(info->name,curr_table->name,IPT_RECENT_NAME_LEN) && (last_table = curr_table) && (curr_table = curr_table->next) );
+ if(!curr_table) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry() create_proc failed, table already destroyed.\n");
+#endif
+ spin_unlock_bh(&recent_lock);
+ return 0;
+ }
+ if(last_table) last_table->next = curr_table->next; else r_tables = curr_table->next;
+ spin_unlock_bh(&recent_lock);
+ vfree(curr_table->time_info);
+ vfree(curr_table->hash_table);
+ vfree(hold);
+ vfree(curr_table->table);
+ vfree(curr_table);
+ return 0;
+ }
+
+ curr_table->status_proc->owner = THIS_MODULE;
+ curr_table->status_proc->data = curr_table;
+ wmb();
+ curr_table->status_proc->read_proc = ip_recent_get_info;
+ curr_table->status_proc->write_proc = ip_recent_ctrl;
+#endif /* CONFIG_PROC_FS */
-static struct seq_operations recent_seq_ops = {
- .start = recent_seq_start,
- .next = recent_seq_next,
- .stop = recent_seq_stop,
- .show = recent_seq_show,
-};
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": checkentry() left.\n");
+#endif
-static int recent_seq_open(struct inode *inode, struct file *file)
-{
- struct proc_dir_entry *pde = PDE(inode);
- struct seq_file *seq;
- struct recent_iter_state *st;
- int ret;
-
- st = kzalloc(sizeof(*st), GFP_KERNEL);
- if (st == NULL)
- return -ENOMEM;
- ret = seq_open(file, &recent_seq_ops);
- if (ret)
- kfree(st);
- st->table = pde->data;
- seq = file->private_data;
- seq->private = st;
- return ret;
+ return 1;
}
-static ssize_t recent_proc_write(struct file *file, const char __user *input,
- size_t size, loff_t *loff)
+/* This function is called in the event that a rule matching this module is
+ * removed.
+ * When this happens we need to check if there are no other rules matching
+ * the table given. If that is the case then we remove the table and clean
+ * up its memory.
+ */
+static void
+destroy(void *matchinfo, unsigned int matchsize)
{
- struct proc_dir_entry *pde = PDE(file->f_dentry->d_inode);
- struct recent_table *t = pde->data;
- struct recent_entry *e;
- char buf[sizeof("+255.255.255.255")], *c = buf;
- u_int32_t addr;
- int add;
-
- if (size > sizeof(buf))
- size = sizeof(buf);
- if (copy_from_user(buf, input, size))
- return -EFAULT;
- while (isspace(*c))
- c++;
-
- if (size - (c - buf) < 5)
- return c - buf;
- if (!strncmp(c, "clear", 5)) {
- c += 5;
- spin_lock_bh(&recent_lock);
- recent_table_flush(t);
+ const struct ipt_recent_info *info = matchinfo;
+ struct recent_ip_tables *curr_table, *last_table;
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": destroy() entered.\n");
+#endif
+
+ if(matchsize != IPT_ALIGN(sizeof(struct ipt_recent_info))) return;
+
+ /* Lock the linked list while we play with it */
+ spin_lock_bh(&recent_lock);
+
+ /* Look for an entry with this name already created */
+ /* Finds the end of the list and the entry before the end if current name does not exist */
+ last_table = NULL;
+ curr_table = r_tables;
+ if(!curr_table) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": destroy() No tables found, leaving.\n");
+#endif
spin_unlock_bh(&recent_lock);
- return c - buf;
+ return;
}
+ while( strncmp(info->name,curr_table->name,IPT_RECENT_NAME_LEN) && (last_table = curr_table) && (curr_table = curr_table->next) );
- switch (*c) {
- case '-':
- add = 0;
- c++;
- break;
- case '+':
- c++;
- default:
- add = 1;
- break;
+ /* If a table does not exist then do nothing and return */
+ if(!curr_table) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": destroy() table not found, leaving.\n");
+#endif
+ spin_unlock_bh(&recent_lock);
+ return;
}
- addr = in_aton(c);
- spin_lock_bh(&recent_lock);
- e = recent_entry_lookup(t, addr, 0);
- if (e == NULL) {
- if (add)
- recent_entry_init(t, addr, 0);
- } else {
- if (add)
- recent_entry_update(t, e);
- else
- recent_entry_remove(t, e);
+ curr_table->count--;
+
+ /* If count is still non-zero then there are still rules referenceing it so we do nothing */
+ if(curr_table->count) {
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": destroy() table found, non-zero count, leaving.\n");
+#endif
+ spin_unlock_bh(&recent_lock);
+ return;
}
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": destroy() table found, zero count, removing.\n");
+#endif
+
+ /* Count must be zero so we remove this table from the list */
+ if(last_table) last_table->next = curr_table->next; else r_tables = curr_table->next;
+
spin_unlock_bh(&recent_lock);
- return size;
-}
-static struct file_operations recent_fops = {
- .open = recent_seq_open,
- .read = seq_read,
- .write = recent_proc_write,
- .release = seq_release_private,
- .owner = THIS_MODULE,
-};
+ /* lock to make sure any late-runners still using this after we removed it from
+ * the list finish up then remove everything */
+ spin_lock_bh(&curr_table->list_lock);
+ spin_unlock_bh(&curr_table->list_lock);
+
+#ifdef CONFIG_PROC_FS
+ if(curr_table->status_proc) remove_proc_entry(curr_table->name,proc_net_ipt_recent);
#endif /* CONFIG_PROC_FS */
+ vfree(curr_table->table[0].last_pkts);
+ vfree(curr_table->table);
+ vfree(curr_table->hash_table);
+ vfree(curr_table->time_info);
+ vfree(curr_table);
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": destroy() left.\n");
+#endif
-static struct ipt_match recent_match = {
- .name = "recent",
- .match = ipt_recent_match,
- .matchsize = sizeof(struct ipt_recent_info),
- .checkentry = ipt_recent_checkentry,
- .destroy = ipt_recent_destroy,
- .me = THIS_MODULE,
+ return;
+}
+
+/* This is the structure we pass to ipt_register to register our
+ * module with iptables.
+ */
+static struct ipt_match recent_match = {
+ .name = "recent",
+ .match = &match,
+ .checkentry = &checkentry,
+ .destroy = &destroy,
+ .me = THIS_MODULE
};
-static int __init ipt_recent_init(void)
+/* Kernel module initialization. */
+static int __init init(void)
{
- int err;
+ int err, count;
- if (!ip_list_tot || !ip_pkt_list_tot || ip_pkt_list_tot > 255)
- return -EINVAL;
- ip_list_hash_size = 1 << fls(ip_list_tot);
-
- err = ipt_register_match(&recent_match);
+ printk(version);
#ifdef CONFIG_PROC_FS
- if (err)
- return err;
- proc_dir = proc_mkdir("ipt_recent", proc_net);
- if (proc_dir == NULL) {
- ipt_unregister_match(&recent_match);
- err = -ENOMEM;
+ proc_net_ipt_recent = proc_mkdir("ipt_recent",proc_net);
+ if(!proc_net_ipt_recent) return -ENOMEM;
+#endif
+
+ if(ip_list_hash_size && ip_list_hash_size <= ip_list_tot) {
+ printk(KERN_WARNING RECENT_NAME ": ip_list_hash_size too small, resetting to default.\n");
+ ip_list_hash_size = 0;
+ }
+
+ if(!ip_list_hash_size) {
+ ip_list_hash_size = ip_list_tot*3;
+ count = 2*2;
+ while(ip_list_hash_size > count) count = count*2;
+ ip_list_hash_size = count;
}
+
+#ifdef DEBUG
+ if(debug) printk(KERN_INFO RECENT_NAME ": ip_list_hash_size: %d\n",ip_list_hash_size);
#endif
+
+ err = ipt_register_match(&recent_match);
+ if (err)
+ remove_proc_entry("ipt_recent", proc_net);
return err;
}
-static void __exit ipt_recent_exit(void)
+/* Kernel module destruction. */
+static void __exit fini(void)
{
- BUG_ON(!list_empty(&tables));
ipt_unregister_match(&recent_match);
-#ifdef CONFIG_PROC_FS
- remove_proc_entry("ipt_recent", proc_net);
-#endif
+
+ remove_proc_entry("ipt_recent",proc_net);
}
-module_init(ipt_recent_init);
-module_exit(ipt_recent_exit);
+/* Register our module with the kernel. */
+module_init(init);
+module_exit(fini);
git://git.onelab.eu / linux-2.6.git / blobdiff