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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /net/netfilter/xt_recent.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'net/netfilter/xt_recent.c')
-rw-r--r--net/netfilter/xt_recent.c763
1 files changed, 763 insertions, 0 deletions
diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
new file mode 100644
index 000000000..7ddb9a78e
--- /dev/null
+++ b/net/netfilter/xt_recent.c
@@ -0,0 +1,763 @@
+// 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. 255)");
+
+#define XT_RECENT_MAX_NSTAMPS 256
+
+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_int8_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;
+ u8 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(struct_size(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(struct_size(t, iphash, ip_list_hash_size), GFP_KERNEL);
+ if (t == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ t->refcnt = 1;
+ t->nstamps_max_mask = nstamp_mask;
+
+ memcpy(&t->mask, &info->mask, sizeof(t->mask));
+ 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
+ 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;
+ const struct list_head *head = e->list.next;
+
+ (*pos)++;
+ while (head == &t->iphash[st->bucket]) {
+ if (++st->bucket >= ip_list_hash_size)
+ return NULL;
+ head = t->iphash[st->bucket].next;
+ }
+ return list_entry(head, struct recent_entry, list);
+}
+
+static void recent_seq_stop(struct seq_file *s, void *v)
+ __releases(recent_lock)
+{
+ spin_unlock_bh(&recent_lock);
+}
+
+static int recent_seq_show(struct seq_file *seq, void *v)
+{
+ const struct recent_entry *e = v;
+ struct recent_iter_state *st = seq->private;
+ const struct recent_table *t = st->table;
+ unsigned int i;
+
+ i = (e->index - 1) & t->nstamps_max_mask;
+
+ if (e->family == NFPROTO_IPV4)
+ seq_printf(seq, "src=%pI4 ttl: %u last_seen: %lu oldest_pkt: %u",
+ &e->addr.ip, e->ttl, e->stamps[i], e->index);
+ else
+ seq_printf(seq, "src=%pI6 ttl: %u last_seen: %lu oldest_pkt: %u",
+ &e->addr.in6, e->ttl, e->stamps[i], e->index);
+ for (i = 0; i < e->nstamps; i++)
+ seq_printf(seq, "%s %lu", i ? "," : "", e->stamps[i]);
+ seq_putc(seq, '\n');
+ return 0;
+}
+
+static const struct seq_operations recent_seq_ops = {
+ .start = recent_seq_start,
+ .next = recent_seq_next,
+ .stop = recent_seq_stop,
+ .show = recent_seq_show,
+};
+
+static int recent_seq_open(struct inode *inode, struct file *file)
+{
+ struct recent_iter_state *st;
+
+ st = __seq_open_private(file, &recent_seq_ops, sizeof(*st));
+ if (st == NULL)
+ return -ENOMEM;
+
+ st->table = pde_data(inode);
+ return 0;
+}
+
+static ssize_t
+recent_mt_proc_write(struct file *file, const char __user *input,
+ size_t size, loff_t *loff)
+{
+ struct recent_table *t = pde_data(file_inode(file));
+ struct recent_entry *e;
+ char buf[sizeof("+b335:1d35:1e55:dead:c0de:1715:5afe:c0de")];
+ const char *c = buf;
+ union nf_inet_addr addr = {};
+ u_int16_t family;
+ bool add, succ;
+
+ if (size == 0)
+ return 0;
+ if (size > sizeof(buf))
+ size = sizeof(buf);
+ if (copy_from_user(buf, input, size) != 0)
+ return -EFAULT;
+
+ /* Strict protocol! */
+ if (*loff != 0)
+ return -ESPIPE;
+ switch (*c) {
+ case '/': /* flush table */
+ spin_lock_bh(&recent_lock);
+ recent_table_flush(t);
+ spin_unlock_bh(&recent_lock);
+ return size;
+ case '-': /* remove address */
+ add = false;
+ break;
+ case '+': /* add address */
+ add = true;
+ break;
+ default:
+ pr_info_ratelimited("Need \"+ip\", \"-ip\" or \"/\"\n");
+ return -EINVAL;
+ }
+
+ ++c;
+ --size;
+ if (strnchr(c, size, ':') != NULL) {
+ family = NFPROTO_IPV6;
+ succ = in6_pton(c, size, (void *)&addr, '\n', NULL);
+ } else {
+ family = NFPROTO_IPV4;
+ succ = in4_pton(c, size, (void *)&addr, '\n', NULL);
+ }
+
+ if (!succ)
+ return -EINVAL;
+
+ spin_lock_bh(&recent_lock);
+ e = recent_entry_lookup(t, &addr, family, 0);
+ if (e == NULL) {
+ if (add)
+ recent_entry_init(t, &addr, family, 0);
+ } else {
+ if (add)
+ recent_entry_update(t, e);
+ else
+ recent_entry_remove(t, e);
+ }
+ spin_unlock_bh(&recent_lock);
+ /* Note we removed one above */
+ *loff += size + 1;
+ return size + 1;
+}
+
+static const struct proc_ops recent_mt_proc_ops = {
+ .proc_open = recent_seq_open,
+ .proc_read = seq_read,
+ .proc_write = recent_mt_proc_write,
+ .proc_release = seq_release_private,
+ .proc_lseek = seq_lseek,
+};
+
+static int __net_init recent_proc_net_init(struct net *net)
+{
+ struct recent_net *recent_net = recent_pernet(net);
+
+ recent_net->xt_recent = proc_mkdir("xt_recent", net->proc_net);
+ if (!recent_net->xt_recent)
+ return -ENOMEM;
+ return 0;
+}
+
+static void __net_exit recent_proc_net_exit(struct net *net)
+{
+ struct recent_net *recent_net = recent_pernet(net);
+ struct recent_table *t;
+
+ /* recent_net_exit() is called before recent_mt_destroy(). Make sure
+ * that the parent xt_recent proc entry is empty before trying to
+ * remove it.
+ */
+ spin_lock_bh(&recent_lock);
+ list_for_each_entry(t, &recent_net->tables, list)
+ remove_proc_entry(t->name, recent_net->xt_recent);
+
+ recent_net->xt_recent = NULL;
+ spin_unlock_bh(&recent_lock);
+
+ remove_proc_entry("xt_recent", net->proc_net);
+}
+#else
+static inline int recent_proc_net_init(struct net *net)
+{
+ return 0;
+}
+
+static inline void recent_proc_net_exit(struct net *net)
+{
+}
+#endif /* CONFIG_PROC_FS */
+
+static int __net_init recent_net_init(struct net *net)
+{
+ struct recent_net *recent_net = recent_pernet(net);
+
+ INIT_LIST_HEAD(&recent_net->tables);
+ return recent_proc_net_init(net);
+}
+
+static void __net_exit recent_net_exit(struct net *net)
+{
+ recent_proc_net_exit(net);
+}
+
+static struct pernet_operations recent_net_ops = {
+ .init = recent_net_init,
+ .exit = recent_net_exit,
+ .id = &recent_net_id,
+ .size = sizeof(struct recent_net),
+};
+
+static struct xt_match recent_mt_reg[] __read_mostly = {
+ {
+ .name = "recent",
+ .revision = 0,
+ .family = NFPROTO_IPV4,
+ .match = recent_mt,
+ .matchsize = sizeof(struct xt_recent_mtinfo),
+ .checkentry = recent_mt_check_v0,
+ .destroy = recent_mt_destroy,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "recent",
+ .revision = 0,
+ .family = NFPROTO_IPV6,
+ .match = recent_mt,
+ .matchsize = sizeof(struct xt_recent_mtinfo),
+ .checkentry = recent_mt_check_v0,
+ .destroy = recent_mt_destroy,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "recent",
+ .revision = 1,
+ .family = NFPROTO_IPV4,
+ .match = recent_mt,
+ .matchsize = sizeof(struct xt_recent_mtinfo_v1),
+ .checkentry = recent_mt_check_v1,
+ .destroy = recent_mt_destroy,
+ .me = THIS_MODULE,
+ },
+ {
+ .name = "recent",
+ .revision = 1,
+ .family = NFPROTO_IPV6,
+ .match = recent_mt,
+ .matchsize = sizeof(struct xt_recent_mtinfo_v1),
+ .checkentry = recent_mt_check_v1,
+ .destroy = recent_mt_destroy,
+ .me = THIS_MODULE,
+ }
+};
+
+static int __init recent_mt_init(void)
+{
+ int err;
+
+ BUILD_BUG_ON_NOT_POWER_OF_2(XT_RECENT_MAX_NSTAMPS);
+
+ if (!ip_list_tot || ip_pkt_list_tot >= XT_RECENT_MAX_NSTAMPS)
+ return -EINVAL;
+ ip_list_hash_size = 1 << fls(ip_list_tot);
+
+ err = register_pernet_subsys(&recent_net_ops);
+ if (err)
+ return err;
+ err = xt_register_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
+ if (err)
+ unregister_pernet_subsys(&recent_net_ops);
+ return err;
+}
+
+static void __exit recent_mt_exit(void)
+{
+ xt_unregister_matches(recent_mt_reg, ARRAY_SIZE(recent_mt_reg));
+ unregister_pernet_subsys(&recent_net_ops);
+}
+
+module_init(recent_mt_init);
+module_exit(recent_mt_exit);