From 404bdbfd242cb99ca0e9d3eb5fbb5bcd54123081 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Mon, 29 May 2006 18:21:34 -0700 Subject: [PATCH] [NETFILTER]: recent match: replace by rewritten version Replace the unmaintainable ipt_recent match by a rewritten version that should be fully compatible. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/ipv4/netfilter/ipt_recent.c | 1268 +++++++++---------------------- 1 file changed, 377 insertions(+), 891 deletions(-) diff --git a/net/ipv4/netfilter/ipt_recent.c b/net/ipv4/netfilter/ipt_recent.c index b847ee409e..9686c4d205 100644 --- a/net/ipv4/netfilter/ipt_recent.c +++ b/net/ipv4/netfilter/ipt_recent.c @@ -1,1007 +1,493 @@ -/* 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 */ -/* 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 -#include +/* + * Copyright (c) 2006 Patrick McHardy + * + * 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 + * Copyright 2002-2003, Stephen Frost, 2.5.x port by laforge@netfilter.org + */ +#include +#include #include -#include -#include -#include +#include +#include #include -#include -#include -#include +#include +#include +#include +#include +#include +#include #include #include -#undef DEBUG -#define HASH_LOG 9 +MODULE_AUTHOR("Patrick McHardy "); +MODULE_DESCRIPTION("IP tables recently seen matching module"); +MODULE_LICENSE("GPL"); -/* 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 . http://snowman.net/projects/ipt_recent/\n"; - -MODULE_AUTHOR("Stephen Frost "); -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); -#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; +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]; }; -/* 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; +struct recent_table { + struct list_head list; + char name[IPT_RECENT_NAME_LEN]; #ifdef CONFIG_PROC_FS - struct proc_dir_entry *status_proc; -#endif /* 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]; }; -/* 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 LIST_HEAD(tables); static DEFINE_SPINLOCK(recent_lock); #ifdef CONFIG_PROC_FS -/* Our /proc/net/ipt_recent entry */ -static struct proc_dir_entry *proc_net_ipt_recent = NULL; -#endif - -/* Function declaration for later. */ -static int -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); - -/* Function to hash a given address into the hash table of table_size size */ -static int hash_func(unsigned int addr, int table_size) -{ - 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); +static struct proc_dir_entry *proc_dir; +static struct file_operations recent_fops; #endif - return(result & (table_size - 1)); -} +static u_int32_t hash_rnd; +static int hash_rnd_initted; -#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) +static unsigned int recent_entry_hash(u_int32_t addr) { - 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; } + if (!hash_rnd_initted) { + get_random_bytes(&hash_rnd, 4); + hash_rnd_initted = 1; } - - *start = buffer + (offset - begin); - len -= (offset - begin); - if(len > length) len = length; - - spin_unlock_bh(&curr_table->list_lock); - return len; + return jhash_1word(addr, hash_rnd) & (ip_list_hash_size - 1); } -/* 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) +static struct recent_entry * +recent_entry_lookup(const struct recent_table *table, u_int32_t addr, u_int8_t ttl) { - 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 + 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; +} - cp = buffer; - while(isspace(*cp)) { cp++; used++; if(used >= len-5) return used; } +static void recent_entry_remove(struct recent_table *t, struct recent_entry *e) +{ + list_del(&e->list); + list_del(&e->lru_list); + kfree(e); + t->entries--; +} - /* 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; - } +static struct recent_entry * +recent_entry_init(struct recent_table *t, u_int32_t addr, u_int8_t ttl) +{ + struct recent_entry *e; - 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; + if (t->entries >= ip_list_tot) { + e = list_entry(t->lru_list.next, struct recent_entry, lru_list); + recent_entry_remove(t, e); } + 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; +} -#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; +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); +} - if(val > max[pp - res.bytes]) return used; - addr = res.word | htonl(val); +static struct recent_table *recent_table_lookup(const char *name) +{ + struct recent_table *t; - if(!addr && check_set == IPT_RECENT_SET) return used; + list_for_each_entry(t, &tables, list) + if (!strcmp(t->name, name)) + return t; + return NULL; +} -#ifdef DEBUG - if(debug) printk(KERN_INFO RECENT_NAME ": ip_recent_ctrl c: %c, addr: %u used: %d\n",c,addr,used); -#endif +static void recent_table_flush(struct recent_table *t) +{ + struct recent_entry *e, *next; + unsigned int i; - /* 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; + 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); } - - 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,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 -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) +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) { - int pkt_count, hits_found, ans; - unsigned long now; const struct ipt_recent_info *info = matchinfo; - 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; + struct recent_table *t; + struct recent_entry *e; + u_int32_t addr; + u_int8_t ttl; + int ret = info->invert; -#ifdef DEBUG - if(debug) printk(KERN_INFO RECENT_NAME ": match(): name = '%s'\n",info->name); -#endif + if (info->side == IPT_RECENT_DEST) + addr = skb->nh.iph->daddr; + else + addr = skb->nh.iph->saddr; - /* 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++; + ttl = skb->nh.iph->ttl; + /* use TTL as seen before forwarding */ + if (out && !skb->sk) + ttl++; - /* Find the right table */ spin_lock_bh(&recent_lock); - 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; + 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; } -#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(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; - } - - /* 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 - - /* 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]; - } - -#ifdef DEBUG - if(debug) printk(KERN_INFO RECENT_NAME ": match(): Collision handled.\n"); -#endif - } - - 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; + 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; } - 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; } - spin_unlock_bh(&curr_table->list_lock); -#ifdef DEBUG - if(debug) printk(KERN_INFO RECENT_NAME ": match() left.\n"); -#endif - return ans; + if (info->check_set & IPT_RECENT_SET || + (info->check_set & IPT_RECENT_UPDATE && ret)) { + recent_entry_update(t, e); + e->ttl = ttl; + } +out: + spin_unlock_bh(&recent_lock); + return ret; } -/* 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, - const struct xt_match *match, - void *matchinfo, - unsigned int matchsize, - unsigned int hook_mask) +ipt_recent_checkentry(const char *tablename, const void *ip, + const struct xt_match *match, 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_ip_tables *curr_table, *find_table, *last_table; - -#ifdef DEBUG - if(debug) printk(KERN_INFO RECENT_NAME ": checkentry() entered.\n"); -#endif - - /* 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; + struct recent_table *t; + unsigned i; + int ret = 0; - /* Name must be set to something */ - if(!info->name || !info->name[0]) return 0; + 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; - /* 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); - return 1; + t = recent_table_lookup(info->name); + if (t != NULL) { + t->refcnt++; + ret = 1; + goto out; } - 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)); + t = kzalloc(sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size, + GFP_ATOMIC); + if (t == NULL) + goto out; + 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; } + t->proc->proc_fops = &recent_fops; + t->proc->data = t; #endif + list_add_tail(&t->list, &tables); + ret = 1; +out: + spin_unlock_bh(&recent_lock); + return ret; +} - 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 - - 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; - } +static void +ipt_recent_destroy(const struct xt_match *match, void *matchinfo, + unsigned int matchsize) +{ + const struct ipt_recent_info *info = matchinfo; + struct recent_table *t; - /* 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); + spin_lock_bh(&recent_lock); + t = recent_table_lookup(info->name); + if (--t->refcnt == 0) { + list_del(&t->list); + recent_table_flush(t); +#ifdef CONFIG_PROC_FS + remove_proc_entry(t->name, proc_dir); #endif - - 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; - } - - for(c = 0; c < ip_list_hash_size; c++) { - curr_table->hash_table[c] = -1; + kfree(t); } + spin_unlock_bh(&recent_lock); +} - /* 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 +#ifdef CONFIG_PROC_FS +struct recent_iter_state { + struct recent_table *table; + unsigned int bucket; +}; - 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; - } +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; - /* 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; - } - if(!last_table) r_tables = curr_table; else last_table->next = curr_table; - spin_unlock_bh(&recent_lock); - -#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) { - vfree(hold); - 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; + 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; } - 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(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 */ - -#ifdef DEBUG - if(debug) printk(KERN_INFO RECENT_NAME ": checkentry() left.\n"); -#endif + return NULL; +} - return 1; +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; + } + (*pos)++; + return list_entry(head, struct recent_entry, list); } -/* 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(const struct xt_match *match, void *matchinfo, unsigned int matchsize) +static void recent_seq_stop(struct seq_file *s, void *v) { - const struct ipt_recent_info *info = matchinfo; - struct recent_ip_tables *curr_table, *last_table; + spin_unlock_bh(&recent_lock); +} -#ifdef DEBUG - if(debug) printk(KERN_INFO RECENT_NAME ": destroy() entered.\n"); -#endif +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; +} - if(matchsize != IPT_ALIGN(sizeof(struct ipt_recent_info))) return; +static struct seq_operations recent_seq_ops = { + .start = recent_seq_start, + .next = recent_seq_next, + .stop = recent_seq_stop, + .show = recent_seq_show, +}; - /* Lock the linked list while we play with it */ - spin_lock_bh(&recent_lock); +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; +} - /* 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 +static ssize_t recent_proc_write(struct file *file, const char __user *input, + size_t size, loff_t *loff) +{ + 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); spin_unlock_bh(&recent_lock); - return; + return c - buf; } - while( strncmp(info->name,curr_table->name,IPT_RECENT_NAME_LEN) && (last_table = curr_table) && (curr_table = curr_table->next) ); - /* 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; + switch (*c) { + case '-': + add = 0; + c++; + break; + case '+': + c++; + default: + add = 1; + break; } + addr = in_aton(c); - 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; + 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); } - -#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; +} - /* 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); +static struct file_operations recent_fops = { + .open = recent_seq_open, + .read = seq_read, + .write = recent_proc_write, + .release = seq_release_private, + .owner = THIS_MODULE, +}; #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 - 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, + .match = ipt_recent_match, .matchsize = sizeof(struct ipt_recent_info), - .checkentry = checkentry, - .destroy = destroy, - .me = THIS_MODULE + .checkentry = ipt_recent_checkentry, + .destroy = ipt_recent_destroy, + .me = THIS_MODULE, }; -/* Kernel module initialization. */ static int __init ipt_recent_init(void) { - int err, count; + int err; - printk(version); -#ifdef CONFIG_PROC_FS - 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 + 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); +#ifdef CONFIG_PROC_FS if (err) - remove_proc_entry("ipt_recent", proc_net); + return err; + proc_dir = proc_mkdir("ipt_recent", proc_net); + if (proc_dir == NULL) { + ipt_unregister_match(&recent_match); + err = -ENOMEM; + } +#endif return err; } -/* Kernel module destruction. */ -static void __exit ipt_recent_fini(void) +static void __exit ipt_recent_exit(void) { + BUG_ON(!list_empty(&tables)); ipt_unregister_match(&recent_match); - - remove_proc_entry("ipt_recent",proc_net); +#ifdef CONFIG_PROC_FS + remove_proc_entry("ipt_recent", proc_net); +#endif } -/* Register our module with the kernel. */ module_init(ipt_recent_init); -module_exit(ipt_recent_fini); +module_exit(ipt_recent_exit); -- 2.39.5