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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /net/netfilter/xt_recent.c | |
download | linux-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.c | 763 |
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); |