// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (c) 2006 Patrick McHardy <kaber@trash.net> * Copyright © CC Computer Consultants GmbH, 2007 - 2008 * * 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 */#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt#include <linux/init.h>#include <linux/ip.h>#include <linux/ipv6.h>#include <linux/module.h>#include <linux/moduleparam.h>#include <linux/proc_fs.h>#include <linux/seq_file.h>#include <linux/string.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/slab.h>#include <linux/vmalloc.h>#include <net/net_namespace.h>#include <net/netns/generic.h> #include <linux/netfilter/x_tables.h>#include <linux/netfilter/xt_recent.h> MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");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"); static unsigned int ip_list_tot __read_mostly = 100;static unsigned int ip_list_hash_size __read_mostly;static unsigned int ip_list_perms __read_mostly = 0644;static unsigned int ip_list_uid __read_mostly;static unsigned int ip_list_gid __read_mostly;module_param(ip_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, 0644);module_param(ip_list_gid, uint, 0644);MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list");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, "default owner of /proc/net/xt_recent/* files");MODULE_PARM_DESC(ip_list_gid, "default owning group of /proc/net/xt_recent/* files"); /* retained for backwards compatibility */static unsigned int ip_pkt_list_tot __read_mostly;module_param(ip_pkt_list_tot, uint, 0400);MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP address to remember (max. 65535)"); #define XT_RECENT_MAX_NSTAMPS 65536 struct recent_entry { struct list_head list; struct list_head lru_list; union nf_inet_addr addr; u_int16_t family; u_int8_t ttl; u_int16_t index; u_int16_t nstamps; unsigned long stamps[];}; struct recent_table { struct list_head list; char name[XT_RECENT_NAME_LEN]; union nf_inet_addr mask; unsigned int refcnt; unsigned int entries; u_int16_t nstamps_max_mask; struct list_head lru_list; struct list_head iphash[];}; struct recent_net { struct list_head tables;#ifdef CONFIG_PROC_FS struct proc_dir_entry *xt_recent;#endif}; static unsigned int recent_net_id __read_mostly; static inline struct recent_net *recent_pernet(struct net *net){ return net_generic(net, recent_net_id);} static DEFINE_SPINLOCK(recent_lock);static DEFINE_MUTEX(recent_mutex); #ifdef CONFIG_PROC_FSstatic const struct proc_ops recent_mt_proc_ops;#endif static u_int32_t hash_rnd __read_mostly; static inline unsigned int recent_entry_hash4(const union nf_inet_addr *addr){ return jhash_1word((__force u32)addr->ip, hash_rnd) & (ip_list_hash_size - 1);} static inline unsigned int recent_entry_hash6(const union nf_inet_addr *addr){ return jhash2((u32 *)addr->ip6, ARRAY_SIZE(addr->ip6), hash_rnd) & (ip_list_hash_size - 1);} static struct recent_entry *recent_entry_lookup(const struct recent_table *table, const union nf_inet_addr *addrp, u_int16_t family, u_int8_t ttl){ struct recent_entry *e; unsigned int h; if (family == NFPROTO_IPV4) h = recent_entry_hash4(addrp); else h = recent_entry_hash6(addrp); list_for_each_entry(e, &table->iphash[h], list) if (e->family == family && memcmp(&e->addr, addrp, sizeof(e->addr)) == 0 && (ttl == e->ttl || ttl == 0 || e->ttl == 0)) return e; return NULL;} 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--;} /* * Drop entries with timestamps older then 'time'. */static void recent_entry_reap(struct recent_table *t, unsigned long time, struct recent_entry *working, bool update){ 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); /* * Do not reap the entry which are going to be updated. */ if (e == working && update) return; /* * 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){ struct recent_entry *e; unsigned int nstamps_max = t->nstamps_max_mask; if (t->entries >= ip_list_tot) { e = list_entry(t->lru_list.next, struct recent_entry, lru_list); recent_entry_remove(t, e); } nstamps_max += 1; e = kmalloc_flex(*e, stamps, nstamps_max, GFP_ATOMIC); if (e == NULL) return NULL; memcpy(&e->addr, addr, sizeof(e->addr)); e->ttl = ttl; e->stamps[0] = jiffies; e->nstamps = 1; e->index = 1; e->family = family; if (family == NFPROTO_IPV4) list_add_tail(&e->list, &t->iphash[recent_entry_hash4(addr)]); else list_add_tail(&e->list, &t->iphash[recent_entry_hash6(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->index &= t->nstamps_max_mask; e->stamps[e->index++] = jiffies; if (e->index > e->nstamps) e->nstamps = e->index; list_move_tail(&e->lru_list, &t->lru_list);} static struct recent_table *recent_table_lookup(struct recent_net *recent_net, const char *name){ struct recent_table *t; list_for_each_entry(t, &recent_net->tables, list) if (!strcmp(t->name, name)) return t; return NULL;} static void recent_table_flush(struct recent_table *t){ struct recent_entry *e, *next; unsigned int i; 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);} static boolrecent_mt(const struct sk_buff *skb, struct xt_action_param *par){ struct net *net = xt_net(par); struct recent_net *recent_net = recent_pernet(net); const struct xt_recent_mtinfo_v1 *info = par->matchinfo; struct recent_table *t; struct recent_entry *e; union nf_inet_addr addr = {}, addr_mask; u_int8_t ttl; bool ret = info->invert; if (xt_family(par) == NFPROTO_IPV4) { const struct iphdr *iph = ip_hdr(skb); if (info->side == XT_RECENT_DEST) addr.ip = iph->daddr; else addr.ip = iph->saddr; ttl = iph->ttl; } else { const struct ipv6hdr *iph = ipv6_hdr(skb); if (info->side == XT_RECENT_DEST) memcpy(&addr.in6, &iph->daddr, sizeof(addr.in6)); else memcpy(&addr.in6, &iph->saddr, sizeof(addr.in6)); ttl = iph->hop_limit; } /* use TTL as seen before forwarding */ if (xt_out(par) != NULL && (!skb->sk || !net_eq(net, sock_net(skb->sk)))) ttl++; spin_lock_bh(&recent_lock); t = recent_table_lookup(recent_net, info->name); nf_inet_addr_mask(&addr, &addr_mask, &t->mask); e = recent_entry_lookup(t, &addr_mask, xt_family(par), (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_mask, xt_family(par), ttl); if (e == NULL) par->hotdrop = true; ret = !ret; goto out; } if (info->check_set & XT_RECENT_SET) ret = !ret; else if (info->check_set & XT_RECENT_REMOVE) { recent_entry_remove(t, e); ret = !ret; } else if (info->check_set & (XT_RECENT_CHECK | XT_RECENT_UPDATE)) { unsigned long time = jiffies - info->seconds * HZ; unsigned int i, hits = 0; for (i = 0; i < e->nstamps; i++) { if (info->seconds && time_after(time, e->stamps[i])) continue; if (!info->hit_count || ++hits >= info->hit_count) { ret = !ret; break; } } /* info->seconds must be non-zero */ if (info->check_set & XT_RECENT_REAP) recent_entry_reap(t, time, e, info->check_set & XT_RECENT_UPDATE && ret); } if (info->check_set & XT_RECENT_SET || (info->check_set & XT_RECENT_UPDATE && ret)) { recent_entry_update(t, e); e->ttl = ttl; }out: spin_unlock_bh(&recent_lock); return ret;} static void recent_table_free(void *addr){ kvfree(addr);} static int recent_mt_check(const struct xt_mtchk_param *par, const struct xt_recent_mtinfo_v1 *info){ struct recent_net *recent_net = recent_pernet(par->net); struct recent_table *t;#ifdef CONFIG_PROC_FS struct proc_dir_entry *pde; kuid_t uid; kgid_t gid;#endif unsigned int nstamp_mask; unsigned int i; int ret = -EINVAL; net_get_random_once(&hash_rnd, sizeof(hash_rnd)); if (info->check_set & ~XT_RECENT_VALID_FLAGS) { pr_info_ratelimited("Unsupported userspace 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 -EINVAL; if ((info->check_set & (XT_RECENT_SET | XT_RECENT_REMOVE)) && (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 >= XT_RECENT_MAX_NSTAMPS) { pr_info_ratelimited("hitcount (%u) is larger than allowed maximum (%u)\n", info->hit_count, XT_RECENT_MAX_NSTAMPS - 1); return -EINVAL; } ret = xt_check_proc_name(info->name, sizeof(info->name)); if (ret) return ret; if (ip_pkt_list_tot && info->hit_count < ip_pkt_list_tot) nstamp_mask = roundup_pow_of_two(ip_pkt_list_tot) - 1; else if (info->hit_count) nstamp_mask = roundup_pow_of_two(info->hit_count) - 1; else nstamp_mask = 32 - 1; mutex_lock(&recent_mutex); t = recent_table_lookup(recent_net, info->name); if (t != NULL) { if (nstamp_mask > t->nstamps_max_mask) { spin_lock_bh(&recent_lock); recent_table_flush(t); t->nstamps_max_mask = nstamp_mask; spin_unlock_bh(&recent_lock); } t->refcnt++; ret = 0; goto out; } t = kvzalloc_flex(*t, iphash, ip_list_hash_size); if (t == NULL) { ret = -ENOMEM; goto out; } t->refcnt = 1; t->nstamps_max_mask = nstamp_mask; memcpy(&t->mask, &info->mask, sizeof(t->mask)); strscpy(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 uid = make_kuid(&init_user_ns, ip_list_uid); gid = make_kgid(&init_user_ns, ip_list_gid); if (!uid_valid(uid) || !gid_valid(gid)) { recent_table_free(t); ret = -EINVAL; goto out; } pde = proc_create_data(t->name, ip_list_perms, recent_net->xt_recent, &recent_mt_proc_ops, t); if (pde == NULL) { recent_table_free(t); ret = -ENOMEM; goto out; } proc_set_user(pde, uid, gid);#endif spin_lock_bh(&recent_lock); list_add_tail(&t->list, &recent_net->tables); spin_unlock_bh(&recent_lock); ret = 0;out: mutex_unlock(&recent_mutex); return ret;} static int recent_mt_check_v0(const struct xt_mtchk_param *par){ const struct xt_recent_mtinfo_v0 *info_v0 = par->matchinfo; struct xt_recent_mtinfo_v1 info_v1; /* Copy revision 0 structure to revision 1 */ memcpy(&info_v1, info_v0, sizeof(struct xt_recent_mtinfo)); /* Set default mask to ensure backward compatible behaviour */ memset(info_v1.mask.all, 0xFF, sizeof(info_v1.mask.all)); return recent_mt_check(par, &info_v1);} static int recent_mt_check_v1(const struct xt_mtchk_param *par){ return recent_mt_check(par, par->matchinfo);} static void recent_mt_destroy(const struct xt_mtdtor_param *par){ struct recent_net *recent_net = recent_pernet(par->net); const struct xt_recent_mtinfo_v1 *info = par->matchinfo; struct recent_table *t; mutex_lock(&recent_mutex); t = recent_table_lookup(recent_net, info->name); if (--t->refcnt == 0) { spin_lock_bh(&recent_lock); list_del(&t->list); spin_unlock_bh(&recent_lock);#ifdef CONFIG_PROC_FS if (recent_net->xt_recent != NULL) remove_proc_entry(t->name, recent_net->xt_recent);#endif recent_table_flush(t); recent_table_free(t); } mutex_unlock(&recent_mutex);} #ifdef CONFIG_PROC_FSstruct recent_iter_state { const struct recent_table *table; unsigned int bucket;}; static void *recent_seq_start(struct seq_file *seq, loff_t *pos) __acquires(recent_lock){ struct recent_iter_state *st = seq->private; const struct recent_table *t = st->table; struct recent_entry *e; loff_t p = *pos; spin_lock_bh(&recent_lock); 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; return NULL;} static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos){ struct recent_iter_state *st = seq->private; const struct recent_table *t = st->table; const struct recent_entry *e = v;Lines 1–500 of 763. 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// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2006 Patrick McHardy <kaber@trash.net> * Copyright © CC Computer Consultants GmbH, 2007 - 2008 * * 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 */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/init.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/string.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/slab.h> #include <linux/vmalloc.h> #include <net/net_namespace.h> #include <net/netns/generic.h> #include <linux/netfilter/x_tables.h> #include <linux/netfilter/xt_recent.h> MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); 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"); static unsigned int ip_list_tot __read_mostly = 100; static unsigned int ip_list_hash_size __read_mostly; static unsigned int ip_list_perms __read_mostly = 0644; static unsigned int ip_list_uid __read_mostly; static unsigned int ip_list_gid __read_mostly; module_param(ip_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, 0644); module_param(ip_list_gid, uint, 0644); MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list"); 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, "default owner of /proc/net/xt_recent/* files"); MODULE_PARM_DESC(ip_list_gid, "default owning group of /proc/net/xt_recent/* files"); /* retained for backwards compatibility */ static unsigned int ip_pkt_list_tot __read_mostly; module_param(ip_pkt_list_tot, uint, 0400); MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP address to remember (max. 65535)"); #define XT_RECENT_MAX_NSTAMPS 65536 struct recent_entry { struct list_head list; struct list_head lru_list; union nf_inet_addr addr; u_int16_t family; u_int8_t ttl; u_int16_t index; u_int16_t nstamps; unsigned long stamps[]; }; struct recent_table { struct list_head list; char name[XT_RECENT_NAME_LEN]; union nf_inet_addr mask; unsigned int refcnt; unsigned int entries; u_int16_t nstamps_max_mask; struct list_head lru_list; struct list_head iphash[]; }; struct recent_net { struct list_head tables; #ifdef CONFIG_PROC_FS struct proc_dir_entry *xt_recent; #endif }; static unsigned int recent_net_id __read_mostly; static inline struct recent_net *recent_pernet(struct net *net) { return net_generic(net, recent_net_id); } static DEFINE_SPINLOCK(recent_lock); static DEFINE_MUTEX(recent_mutex); #ifdef CONFIG_PROC_FS static const struct proc_ops recent_mt_proc_ops; #endif static u_int32_t hash_rnd __read_mostly; static inline unsigned int recent_entry_hash4(const union nf_inet_addr *addr) { return jhash_1word((__force u32)addr->ip, hash_rnd) & (ip_list_hash_size - 1); } static inline unsigned int recent_entry_hash6(const union nf_inet_addr *addr) { return jhash2((u32 *)addr->ip6, ARRAY_SIZE(addr->ip6), hash_rnd) & (ip_list_hash_size - 1); } static struct recent_entry * recent_entry_lookup(const struct recent_table *table, const union nf_inet_addr *addrp, u_int16_t family, u_int8_t ttl) { struct recent_entry *e; unsigned int h; if (family == NFPROTO_IPV4) h = recent_entry_hash4(addrp); else h = recent_entry_hash6(addrp); list_for_each_entry(e, &table->iphash[h], list) if (e->family == family && memcmp(&e->addr, addrp, sizeof(e->addr)) == 0 && (ttl == e->ttl || ttl == 0 || e->ttl == 0)) return e; return NULL; } 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--; } /* * Drop entries with timestamps older then 'time'. */ static void recent_entry_reap(struct recent_table *t, unsigned long time, struct recent_entry *working, bool update) { 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); /* * Do not reap the entry which are going to be updated. */ if (e == working && update) return; /* * 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) { struct recent_entry *e; unsigned int nstamps_max = t->nstamps_max_mask; if (t->entries >= ip_list_tot) { e = list_entry(t->lru_list.next, struct recent_entry, lru_list); recent_entry_remove(t, e); } nstamps_max += 1; e = kmalloc_flex(*e, stamps, nstamps_max, GFP_ATOMIC); if (e == NULL) return NULL; memcpy(&e->addr, addr, sizeof(e->addr)); e->ttl = ttl; e->stamps[0] = jiffies; e->nstamps = 1; e->index = 1; e->family = family; if (family == NFPROTO_IPV4) list_add_tail(&e->list, &t->iphash[recent_entry_hash4(addr)]); else list_add_tail(&e->list, &t->iphash[recent_entry_hash6(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->index &= t->nstamps_max_mask; e->stamps[e->index++] = jiffies; if (e->index > e->nstamps) e->nstamps = e->index; list_move_tail(&e->lru_list, &t->lru_list); } static struct recent_table *recent_table_lookup(struct recent_net *recent_net, const char *name) { struct recent_table *t; list_for_each_entry(t, &recent_net->tables, list) if (!strcmp(t->name, name)) return t; return NULL; } static void recent_table_flush(struct recent_table *t) { struct recent_entry *e, *next; unsigned int i; 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); } static bool recent_mt(const struct sk_buff *skb, struct xt_action_param *par) { struct net *net = xt_net(par); struct recent_net *recent_net = recent_pernet(net); const struct xt_recent_mtinfo_v1 *info = par->matchinfo; struct recent_table *t; struct recent_entry *e; union nf_inet_addr addr = {}, addr_mask; u_int8_t ttl; bool ret = info->invert; if (xt_family(par) == NFPROTO_IPV4) { const struct iphdr *iph = ip_hdr(skb); if (info->side == XT_RECENT_DEST) addr.ip = iph->daddr; else addr.ip = iph->saddr; ttl = iph->ttl; } else { const struct ipv6hdr *iph = ipv6_hdr(skb); if (info->side == XT_RECENT_DEST) memcpy(&addr.in6, &iph->daddr, sizeof(addr.in6)); else memcpy(&addr.in6, &iph->saddr, sizeof(addr.in6)); ttl = iph->hop_limit; } /* use TTL as seen before forwarding */ if (xt_out(par) != NULL && (!skb->sk || !net_eq(net, sock_net(skb->sk)))) ttl++; spin_lock_bh(&recent_lock); t = recent_table_lookup(recent_net, info->name); nf_inet_addr_mask(&addr, &addr_mask, &t->mask); e = recent_entry_lookup(t, &addr_mask, xt_family(par), (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_mask, xt_family(par), ttl); if (e == NULL) par->hotdrop = true; ret = !ret; goto out; } if (info->check_set & XT_RECENT_SET) ret = !ret; else if (info->check_set & XT_RECENT_REMOVE) { recent_entry_remove(t, e); ret = !ret; } else if (info->check_set & (XT_RECENT_CHECK | XT_RECENT_UPDATE)) { unsigned long time = jiffies - info->seconds * HZ; unsigned int i, hits = 0; for (i = 0; i < e->nstamps; i++) { if (info->seconds && time_after(time, e->stamps[i])) continue; if (!info->hit_count || ++hits >= info->hit_count) { ret = !ret; break; } } /* info->seconds must be non-zero */ if (info->check_set & XT_RECENT_REAP) recent_entry_reap(t, time, e, info->check_set & XT_RECENT_UPDATE && ret); } if (info->check_set & XT_RECENT_SET || (info->check_set & XT_RECENT_UPDATE && ret)) { recent_entry_update(t, e); e->ttl = ttl; } out: spin_unlock_bh(&recent_lock); return ret; } static void recent_table_free(void *addr) { kvfree(addr); } static int recent_mt_check(const struct xt_mtchk_param *par, const struct xt_recent_mtinfo_v1 *info) { struct recent_net *recent_net = recent_pernet(par->net); struct recent_table *t; #ifdef CONFIG_PROC_FS struct proc_dir_entry *pde; kuid_t uid; kgid_t gid; #endif unsigned int nstamp_mask; unsigned int i; int ret = -EINVAL; net_get_random_once(&hash_rnd, sizeof(hash_rnd)); if (info->check_set & ~XT_RECENT_VALID_FLAGS) { pr_info_ratelimited("Unsupported userspace 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 -EINVAL; if ((info->check_set & (XT_RECENT_SET | XT_RECENT_REMOVE)) && (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 >= XT_RECENT_MAX_NSTAMPS) { pr_info_ratelimited("hitcount (%u) is larger than allowed maximum (%u)\n", info->hit_count, XT_RECENT_MAX_NSTAMPS - 1); return -EINVAL; } ret = xt_check_proc_name(info->name, sizeof(info->name)); if (ret) return ret; if (ip_pkt_list_tot && info->hit_count < ip_pkt_list_tot) nstamp_mask = roundup_pow_of_two(ip_pkt_list_tot) - 1; else if (info->hit_count) nstamp_mask = roundup_pow_of_two(info->hit_count) - 1; else nstamp_mask = 32 - 1; mutex_lock(&recent_mutex); t = recent_table_lookup(recent_net, info->name); if (t != NULL) { if (nstamp_mask > t->nstamps_max_mask) { spin_lock_bh(&recent_lock); recent_table_flush(t); t->nstamps_max_mask = nstamp_mask; spin_unlock_bh(&recent_lock); } t->refcnt++; ret = 0; goto out; } t = kvzalloc_flex(*t, iphash, ip_list_hash_size); if (t == NULL) { ret = -ENOMEM; goto out; } t->refcnt = 1; t->nstamps_max_mask = nstamp_mask; memcpy(&t->mask, &info->mask, sizeof(t->mask)); strscpy(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 uid = make_kuid(&init_user_ns, ip_list_uid); gid = make_kgid(&init_user_ns, ip_list_gid); if (!uid_valid(uid) || !gid_valid(gid)) { recent_table_free(t); ret = -EINVAL; goto out; } pde = proc_create_data(t->name, ip_list_perms, recent_net->xt_recent, &recent_mt_proc_ops, t); if (pde == NULL) { recent_table_free(t); ret = -ENOMEM; goto out; } proc_set_user(pde, uid, gid); #endif spin_lock_bh(&recent_lock); list_add_tail(&t->list, &recent_net->tables); spin_unlock_bh(&recent_lock); ret = 0; out: mutex_unlock(&recent_mutex); return ret; } static int recent_mt_check_v0(const struct xt_mtchk_param *par) { const struct xt_recent_mtinfo_v0 *info_v0 = par->matchinfo; struct xt_recent_mtinfo_v1 info_v1; /* Copy revision 0 structure to revision 1 */ memcpy(&info_v1, info_v0, sizeof(struct xt_recent_mtinfo)); /* Set default mask to ensure backward compatible behaviour */ memset(info_v1.mask.all, 0xFF, sizeof(info_v1.mask.all)); return recent_mt_check(par, &info_v1); } static int recent_mt_check_v1(const struct xt_mtchk_param *par) { return recent_mt_check(par, par->matchinfo); } static void recent_mt_destroy(const struct xt_mtdtor_param *par) { struct recent_net *recent_net = recent_pernet(par->net); const struct xt_recent_mtinfo_v1 *info = par->matchinfo; struct recent_table *t; mutex_lock(&recent_mutex); t = recent_table_lookup(recent_net, info->name); if (--t->refcnt == 0) { spin_lock_bh(&recent_lock); list_del(&t->list); spin_unlock_bh(&recent_lock); #ifdef CONFIG_PROC_FS if (recent_net->xt_recent != NULL) remove_proc_entry(t->name, recent_net->xt_recent); #endif recent_table_flush(t); recent_table_free(t); } mutex_unlock(&recent_mutex); } #ifdef CONFIG_PROC_FS struct recent_iter_state { const struct recent_table *table; unsigned int bucket; }; static void *recent_seq_start(struct seq_file *seq, loff_t *pos) __acquires(recent_lock) { struct recent_iter_state *st = seq->private; const struct recent_table *t = st->table; struct recent_entry *e; loff_t p = *pos; spin_lock_bh(&recent_lock); 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; return NULL; } static void *recent_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct recent_iter_state *st = seq->private; const struct recent_table *t = st->table; const struct recent_entry *e = v;