diff options
Diffstat (limited to 'net/netfilter/xt_recent.c')
-rw-r--r-- | net/netfilter/xt_recent.c | 185 |
1 files changed, 57 insertions, 128 deletions
diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index 834b736..b88d63b 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -12,6 +12,7 @@ * Author: Stephen Frost <sfrost@snowman.net> * Copyright 2002-2003, Stephen Frost, 2.5.x port by laforge@netfilter.org */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/init.h> #include <linux/ip.h> #include <linux/ipv6.h> @@ -35,8 +36,8 @@ #include <linux/netfilter/xt_recent.h> MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); -MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>"); -MODULE_DESCRIPTION("Xtables: \"recently-seen\" host matching for IPv4"); +MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>"); +MODULE_DESCRIPTION("Xtables: \"recently-seen\" host matching"); MODULE_LICENSE("GPL"); MODULE_ALIAS("ipt_recent"); MODULE_ALIAS("ip6t_recent"); @@ -51,14 +52,14 @@ 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_param(ip_list_uid, uint, 0400); -module_param(ip_list_gid, uint, 0400); +module_param(ip_list_uid, uint, S_IRUGO | S_IWUSR); +module_param(ip_list_gid, uint, S_IRUGO | S_IWUSR); 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 address 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/xt_recent/* files"); -MODULE_PARM_DESC(ip_list_uid,"owner of /proc/net/xt_recent/* files"); -MODULE_PARM_DESC(ip_list_gid,"owning group of /proc/net/xt_recent/* files"); +MODULE_PARM_DESC(ip_list_uid, "default owner of /proc/net/xt_recent/* files"); +MODULE_PARM_DESC(ip_list_gid, "default owning group of /proc/net/xt_recent/* files"); struct recent_entry { struct list_head list; @@ -84,9 +85,6 @@ struct recent_net { struct list_head tables; #ifdef CONFIG_PROC_FS struct proc_dir_entry *xt_recent; -#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT - struct proc_dir_entry *ipt_recent; -#endif #endif }; @@ -147,6 +145,25 @@ static void recent_entry_remove(struct recent_table *t, struct recent_entry *e) t->entries--; } +/* + * Drop entries with timestamps older then 'time'. + */ +static void recent_entry_reap(struct recent_table *t, unsigned long time) +{ + struct recent_entry *e; + + /* + * The head of the LRU list is always the oldest entry. + */ + e = list_entry(t->lru_list.next, struct recent_entry, lru_list); + + /* + * The last time stamp is the most recent. + */ + if (time_after(time, e->stamps[e->index-1])) + recent_entry_remove(t, e); +} + static struct recent_entry * recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr, u_int16_t family, u_int8_t ttl) @@ -218,7 +235,7 @@ recent_mt(const struct sk_buff *skb, const struct xt_match_param *par) u_int8_t ttl; bool ret = info->invert; - if (par->match->family == NFPROTO_IPV4) { + if (par->family == NFPROTO_IPV4) { const struct iphdr *iph = ip_hdr(skb); if (info->side == XT_RECENT_DEST) @@ -244,12 +261,12 @@ recent_mt(const struct sk_buff *skb, const struct xt_match_param *par) spin_lock_bh(&recent_lock); t = recent_table_lookup(recent_net, info->name); - e = recent_entry_lookup(t, &addr, par->match->family, + e = recent_entry_lookup(t, &addr, par->family, (info->check_set & XT_RECENT_TTL) ? ttl : 0); if (e == NULL) { if (!(info->check_set & XT_RECENT_SET)) goto out; - e = recent_entry_init(t, &addr, par->match->family, ttl); + e = recent_entry_init(t, &addr, par->family, ttl); if (e == NULL) *par->hotdrop = true; ret = !ret; @@ -273,6 +290,10 @@ recent_mt(const struct sk_buff *skb, const struct xt_match_param *par) break; } } + + /* info->seconds must be non-zero */ + if (info->check_set & XT_RECENT_REAP) + recent_entry_reap(t, time); } if (info->check_set & XT_RECENT_SET || @@ -285,7 +306,7 @@ out: return ret; } -static bool recent_mt_check(const struct xt_mtchk_param *par) +static int recent_mt_check(const struct xt_mtchk_param *par) { struct recent_net *recent_net = recent_pernet(par->net); const struct xt_recent_mtinfo *info = par->matchinfo; @@ -294,41 +315,51 @@ static bool recent_mt_check(const struct xt_mtchk_param *par) struct proc_dir_entry *pde; #endif unsigned i; - bool ret = false; + int ret = -EINVAL; if (unlikely(!hash_rnd_inited)) { get_random_bytes(&hash_rnd, sizeof(hash_rnd)); hash_rnd_inited = true; } + if (info->check_set & ~XT_RECENT_VALID_FLAGS) { + pr_info("Unsupported user space flags (%08x)\n", + info->check_set); + return -EINVAL; + } if (hweight8(info->check_set & (XT_RECENT_SET | XT_RECENT_REMOVE | XT_RECENT_CHECK | XT_RECENT_UPDATE)) != 1) - return false; + return -EINVAL; if ((info->check_set & (XT_RECENT_SET | XT_RECENT_REMOVE)) && - (info->seconds || info->hit_count)) - return false; + (info->seconds || info->hit_count || + (info->check_set & XT_RECENT_MODIFIERS))) + return -EINVAL; + if ((info->check_set & XT_RECENT_REAP) && !info->seconds) + return -EINVAL; if (info->hit_count > ip_pkt_list_tot) { - pr_info(KBUILD_MODNAME ": hitcount (%u) is larger than " + pr_info("hitcount (%u) is larger than " "packets to be remembered (%u)\n", info->hit_count, ip_pkt_list_tot); - return false; + return -EINVAL; } if (info->name[0] == '\0' || strnlen(info->name, XT_RECENT_NAME_LEN) == XT_RECENT_NAME_LEN) - return false; + return -EINVAL; mutex_lock(&recent_mutex); t = recent_table_lookup(recent_net, info->name); if (t != NULL) { t->refcnt++; - ret = true; + ret = 0; goto out; } t = kzalloc(sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size, GFP_KERNEL); - if (t == NULL) + if (t == NULL) { + ret = -ENOMEM; goto out; + } t->refcnt = 1; strcpy(t->name, info->name); INIT_LIST_HEAD(&t->lru_list); @@ -339,26 +370,16 @@ static bool recent_mt_check(const struct xt_mtchk_param *par) &recent_mt_fops, t); if (pde == NULL) { kfree(t); - goto out; - } - pde->uid = ip_list_uid; - pde->gid = ip_list_gid; -#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT - pde = proc_create_data(t->name, ip_list_perms, recent_net->ipt_recent, - &recent_old_fops, t); - if (pde == NULL) { - remove_proc_entry(t->name, recent_net->xt_recent); - kfree(t); + ret = -ENOMEM; goto out; } pde->uid = ip_list_uid; pde->gid = ip_list_gid; #endif -#endif spin_lock_bh(&recent_lock); list_add_tail(&t->list, &recent_net->tables); spin_unlock_bh(&recent_lock); - ret = true; + ret = 0; out: mutex_unlock(&recent_mutex); return ret; @@ -377,9 +398,6 @@ static void recent_mt_destroy(const struct xt_mtdtor_param *par) list_del(&t->list); spin_unlock_bh(&recent_lock); #ifdef CONFIG_PROC_FS -#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT - remove_proc_entry(t->name, recent_net->ipt_recent); -#endif remove_proc_entry(t->name, recent_net->xt_recent); #endif recent_table_flush(t); @@ -471,84 +489,6 @@ static int recent_seq_open(struct inode *inode, struct file *file) return 0; } -#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT -static int recent_old_seq_open(struct inode *inode, struct file *filp) -{ - static bool warned_of_old; - - if (unlikely(!warned_of_old)) { - printk(KERN_INFO KBUILD_MODNAME ": Use of /proc/net/ipt_recent" - " is deprecated; use /proc/net/xt_recent.\n"); - warned_of_old = true; - } - return recent_seq_open(inode, filp); -} - -static ssize_t recent_old_proc_write(struct file *file, - const char __user *input, - size_t size, loff_t *loff) -{ - const struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode); - struct recent_table *t = pde->data; - struct recent_entry *e; - char buf[sizeof("+255.255.255.255")], *c = buf; - union nf_inet_addr addr = {}; - int add; - - if (size > sizeof(buf)) - size = sizeof(buf); - if (copy_from_user(buf, input, size)) - return -EFAULT; - - c = skip_spaces(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 c - buf; - } - - switch (*c) { - case '-': - add = 0; - c++; - break; - case '+': - c++; - default: - add = 1; - break; - } - addr.ip = in_aton(c); - - spin_lock_bh(&recent_lock); - e = recent_entry_lookup(t, &addr, NFPROTO_IPV4, 0); - if (e == NULL) { - if (add) - recent_entry_init(t, &addr, NFPROTO_IPV4, 0); - } else { - if (add) - recent_entry_update(t, e); - else - recent_entry_remove(t, e); - } - spin_unlock_bh(&recent_lock); - return size; -} - -static const struct file_operations recent_old_fops = { - .open = recent_old_seq_open, - .read = seq_read, - .write = recent_old_proc_write, - .release = seq_release_private, - .owner = THIS_MODULE, -}; -#endif - static ssize_t recent_mt_proc_write(struct file *file, const char __user *input, size_t size, loff_t *loff) @@ -585,7 +525,7 @@ recent_mt_proc_write(struct file *file, const char __user *input, add = true; break; default: - printk(KERN_INFO KBUILD_MODNAME ": Need +ip, -ip or /\n"); + pr_info("Need \"+ip\", \"-ip\" or \"/\"\n"); return -EINVAL; } @@ -600,8 +540,7 @@ recent_mt_proc_write(struct file *file, const char __user *input, } if (!succ) { - printk(KERN_INFO KBUILD_MODNAME ": illegal address written " - "to procfs\n"); + pr_info("illegal address written to procfs\n"); return -EINVAL; } @@ -637,21 +576,11 @@ static int __net_init recent_proc_net_init(struct net *net) recent_net->xt_recent = proc_mkdir("xt_recent", net->proc_net); if (!recent_net->xt_recent) return -ENOMEM; -#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT - recent_net->ipt_recent = proc_mkdir("ipt_recent", net->proc_net); - if (!recent_net->ipt_recent) { - proc_net_remove(net, "xt_recent"); - return -ENOMEM; - } -#endif return 0; } static void __net_exit recent_proc_net_exit(struct net *net) { -#ifdef CONFIG_NETFILTER_XT_MATCH_RECENT_PROC_COMPAT - proc_net_remove(net, "ipt_recent"); -#endif proc_net_remove(net, "xt_recent"); } #else |