1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991001011021031041051061071081091101111121131141151161171181191201211221231241251261271281291301311321331341351361371381391401411421431441451461471481491501511521531541551561571581591601611621631641651661671681691701711721731741751761771781791801811821831841851861871881891901911921931941951961971981992002012022032042052062072082092102112122132142152162172182192202212222232242252262272282292302312322332342352362372382392402412422432442452462472482492502512522532542552562572582592602612622632642652662672682692702712722732742752762772782792802812822832842852862872882892902912922932942952962972982993003013023033043053063073083093103113123133143153163173183193203213223233243253263273283293303313323333343353363373383393403413423433443453463473483493503513523533543553563573583593603613623633643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943953963973983994004014024034044054064074084094104114124134144154164174184194204214224234244254264274284294304314324334344354364374384394404414424434444454464474484494504514524534544554564574584594604614624634644654664674684694704714724734744754764774784794804814824834844854864874884894904914924934944954964974984995005015025035045055065075085095105115125135145155165175185195205215225235245255265275285295305315325335345355365375385395405415425435445455465475485495505515525535545555565575585595605615625635645655665675685695705715725735745755765775785795805815825835845855865875885895905915925935945955965975985996006016026036046056066076086096106116126136146156166176186196206216226236246256266276286296306316326336346356366376386396406416426436446456466476486496506516526536546556566576586596606616626636646656666676686696706716726736746756766776786796806816826836846856866876886896906916926936946956966976986997007017027037047057067077087097107117127137147157167177187197207217227237247257267277287297307317327337347357367377387397407417427437447457467477487497507517527537547557567577587597607617627637647657667677687697707717727737747757767777787797807817827837847857867877887897907917927937947957967977987998008018028038048058068078088098108118128138148158168178188198208218228238248258268278288298308318328338348358368378388398408418428438448458468478488498508518528538548558568578588598608618628638648658668678688698708718728738748758768778788798808818828838848858868878888898908918928938948958968978988999009019029039049059069079089099109119129139149159169179189199209219229239249259269279289299309319329339349359369379389399409419429439449459469479489499509519529539549559569579589599609619629639649659669679689699709719729739749759769779789799809819829839849859869879889899909919929939949959969979989991000100110021003100410051006100710081009101010111012101310141015101610171018101910201021102210231024102510261027102810291030103110321033103410351036103710381039104010411042104310441045104610471048104910501051105210531054105510561057105810591060106110621063106410651066106710681069107010711072107310741075107610771078107910801081108210831084108510861087108810891090109110921093109410951096109710981099110011011102110311041105110611071108110911101111111211131114111511161117111811191120112111221123112411251126112711281129113011311132113311341135113611371138113911401141114211431144 |
- /*
- * This is a module which is used for queueing packets and communicating with
- * userspace via nfetlink.
- *
- * (C) 2005 by Harald Welte <laforge@netfilter.org>
- *
- * Based on the old ipv4-only ip_queue.c:
- * (C) 2000-2002 James Morris <jmorris@intercode.com.au>
- * (C) 2003-2005 Netfilter Core Team <coreteam@netfilter.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- */
- #include <linux/module.h>
- #include <linux/skbuff.h>
- #include <linux/init.h>
- #include <linux/spinlock.h>
- #include <linux/notifier.h>
- #include <linux/netdevice.h>
- #include <linux/netfilter.h>
- #include <linux/proc_fs.h>
- #include <linux/netfilter_ipv4.h>
- #include <linux/netfilter_ipv6.h>
- #include <linux/netfilter/nfnetlink.h>
- #include <linux/netfilter/nfnetlink_queue.h>
- #include <linux/list.h>
- #include <net/sock.h>
- #include <asm/atomic.h>
- #ifdef CONFIG_BRIDGE_NETFILTER
- #include "../bridge/br_private.h"
- #endif
- #define NFQNL_QMAX_DEFAULT 1024
- #if 0
- #define QDEBUG(x, args ...) printk(KERN_DEBUG "%s(%d):%s(): " x, \
- __FILE__, __LINE__, __FUNCTION__, \
- ## args)
- #else
- #define QDEBUG(x, ...)
- #endif
- struct nfqnl_queue_entry {
- struct list_head list;
- struct nf_info *info;
- struct sk_buff *skb;
- unsigned int id;
- };
- struct nfqnl_instance {
- struct hlist_node hlist; /* global list of queues */
- atomic_t use;
- int peer_pid;
- unsigned int queue_maxlen;
- unsigned int copy_range;
- unsigned int queue_total;
- unsigned int queue_dropped;
- unsigned int queue_user_dropped;
- atomic_t id_sequence; /* 'sequence' of pkt ids */
- u_int16_t queue_num; /* number of this queue */
- u_int8_t copy_mode;
- spinlock_t lock;
- struct list_head queue_list; /* packets in queue */
- };
- typedef int (*nfqnl_cmpfn)(struct nfqnl_queue_entry *, unsigned long);
- static DEFINE_RWLOCK(instances_lock);
- #define INSTANCE_BUCKETS 16
- static struct hlist_head instance_table[INSTANCE_BUCKETS];
- static inline u_int8_t instance_hashfn(u_int16_t queue_num)
- {
- return ((queue_num >> 8) | queue_num) % INSTANCE_BUCKETS;
- }
- static struct nfqnl_instance *
- __instance_lookup(u_int16_t queue_num)
- {
- struct hlist_head *head;
- struct hlist_node *pos;
- struct nfqnl_instance *inst;
- head = &instance_table[instance_hashfn(queue_num)];
- hlist_for_each_entry(inst, pos, head, hlist) {
- if (inst->queue_num == queue_num)
- return inst;
- }
- return NULL;
- }
- static struct nfqnl_instance *
- instance_lookup_get(u_int16_t queue_num)
- {
- struct nfqnl_instance *inst;
- read_lock_bh(&instances_lock);
- inst = __instance_lookup(queue_num);
- if (inst)
- atomic_inc(&inst->use);
- read_unlock_bh(&instances_lock);
- return inst;
- }
- static void
- instance_put(struct nfqnl_instance *inst)
- {
- if (inst && atomic_dec_and_test(&inst->use)) {
- QDEBUG("kfree(inst=%p)\n", inst);
- kfree(inst);
- }
- }
- static struct nfqnl_instance *
- instance_create(u_int16_t queue_num, int pid)
- {
- struct nfqnl_instance *inst;
- QDEBUG("entering for queue_num=%u, pid=%d\n", queue_num, pid);
- write_lock_bh(&instances_lock);
- if (__instance_lookup(queue_num)) {
- inst = NULL;
- QDEBUG("aborting, instance already exists\n");
- goto out_unlock;
- }
- inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
- if (!inst)
- goto out_unlock;
- inst->queue_num = queue_num;
- inst->peer_pid = pid;
- inst->queue_maxlen = NFQNL_QMAX_DEFAULT;
- inst->copy_range = 0xfffff;
- inst->copy_mode = NFQNL_COPY_NONE;
- atomic_set(&inst->id_sequence, 0);
- /* needs to be two, since we _put() after creation */
- atomic_set(&inst->use, 2);
- spin_lock_init(&inst->lock);
- INIT_LIST_HEAD(&inst->queue_list);
- if (!try_module_get(THIS_MODULE))
- goto out_free;
- hlist_add_head(&inst->hlist,
- &instance_table[instance_hashfn(queue_num)]);
- write_unlock_bh(&instances_lock);
- QDEBUG("successfully created new instance\n");
- return inst;
- out_free:
- kfree(inst);
- out_unlock:
- write_unlock_bh(&instances_lock);
- return NULL;
- }
- static void nfqnl_flush(struct nfqnl_instance *queue, int verdict);
- static void
- _instance_destroy2(struct nfqnl_instance *inst, int lock)
- {
- /* first pull it out of the global list */
- if (lock)
- write_lock_bh(&instances_lock);
- QDEBUG("removing instance %p (queuenum=%u) from hash\n",
- inst, inst->queue_num);
- hlist_del(&inst->hlist);
- if (lock)
- write_unlock_bh(&instances_lock);
- /* then flush all pending skbs from the queue */
- nfqnl_flush(inst, NF_DROP);
- /* and finally put the refcount */
- instance_put(inst);
- module_put(THIS_MODULE);
- }
- static inline void
- __instance_destroy(struct nfqnl_instance *inst)
- {
- _instance_destroy2(inst, 0);
- }
- static inline void
- instance_destroy(struct nfqnl_instance *inst)
- {
- _instance_destroy2(inst, 1);
- }
- static void
- issue_verdict(struct nfqnl_queue_entry *entry, int verdict)
- {
- QDEBUG("entering for entry %p, verdict %u\n", entry, verdict);
- /* TCP input path (and probably other bits) assume to be called
- * from softirq context, not from syscall, like issue_verdict is
- * called. TCP input path deadlocks with locks taken from timer
- * softirq, e.g. We therefore emulate this by local_bh_disable() */
- local_bh_disable();
- nf_reinject(entry->skb, entry->info, verdict);
- local_bh_enable();
- kfree(entry);
- }
- static inline void
- __enqueue_entry(struct nfqnl_instance *queue,
- struct nfqnl_queue_entry *entry)
- {
- list_add(&entry->list, &queue->queue_list);
- queue->queue_total++;
- }
- /*
- * Find and return a queued entry matched by cmpfn, or return the last
- * entry if cmpfn is NULL.
- */
- static inline struct nfqnl_queue_entry *
- __find_entry(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
- unsigned long data)
- {
- struct list_head *p;
- list_for_each_prev(p, &queue->queue_list) {
- struct nfqnl_queue_entry *entry = (struct nfqnl_queue_entry *)p;
- if (!cmpfn || cmpfn(entry, data))
- return entry;
- }
- return NULL;
- }
- static inline void
- __dequeue_entry(struct nfqnl_instance *q, struct nfqnl_queue_entry *entry)
- {
- list_del(&entry->list);
- q->queue_total--;
- }
- static inline struct nfqnl_queue_entry *
- __find_dequeue_entry(struct nfqnl_instance *queue,
- nfqnl_cmpfn cmpfn, unsigned long data)
- {
- struct nfqnl_queue_entry *entry;
- entry = __find_entry(queue, cmpfn, data);
- if (entry == NULL)
- return NULL;
- __dequeue_entry(queue, entry);
- return entry;
- }
- static inline void
- __nfqnl_flush(struct nfqnl_instance *queue, int verdict)
- {
- struct nfqnl_queue_entry *entry;
- while ((entry = __find_dequeue_entry(queue, NULL, 0)))
- issue_verdict(entry, verdict);
- }
- static inline int
- __nfqnl_set_mode(struct nfqnl_instance *queue,
- unsigned char mode, unsigned int range)
- {
- int status = 0;
- switch (mode) {
- case NFQNL_COPY_NONE:
- case NFQNL_COPY_META:
- queue->copy_mode = mode;
- queue->copy_range = 0;
- break;
- case NFQNL_COPY_PACKET:
- queue->copy_mode = mode;
- /* we're using struct nfattr which has 16bit nfa_len */
- if (range > 0xffff)
- queue->copy_range = 0xffff;
- else
- queue->copy_range = range;
- break;
- default:
- status = -EINVAL;
- }
- return status;
- }
- static struct nfqnl_queue_entry *
- find_dequeue_entry(struct nfqnl_instance *queue,
- nfqnl_cmpfn cmpfn, unsigned long data)
- {
- struct nfqnl_queue_entry *entry;
- spin_lock_bh(&queue->lock);
- entry = __find_dequeue_entry(queue, cmpfn, data);
- spin_unlock_bh(&queue->lock);
- return entry;
- }
- static void
- nfqnl_flush(struct nfqnl_instance *queue, int verdict)
- {
- spin_lock_bh(&queue->lock);
- __nfqnl_flush(queue, verdict);
- spin_unlock_bh(&queue->lock);
- }
- static struct sk_buff *
- nfqnl_build_packet_message(struct nfqnl_instance *queue,
- struct nfqnl_queue_entry *entry, int *errp)
- {
- unsigned char *old_tail;
- size_t size;
- size_t data_len = 0;
- struct sk_buff *skb;
- struct nfqnl_msg_packet_hdr pmsg;
- struct nlmsghdr *nlh;
- struct nfgenmsg *nfmsg;
- struct nf_info *entinf = entry->info;
- struct sk_buff *entskb = entry->skb;
- struct net_device *indev;
- struct net_device *outdev;
- __be32 tmp_uint;
- QDEBUG("entered\n");
- /* all macros expand to constant values at compile time */
- size = NLMSG_SPACE(sizeof(struct nfgenmsg)) +
- + NFA_SPACE(sizeof(struct nfqnl_msg_packet_hdr))
- + NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
- + NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
- #ifdef CONFIG_BRIDGE_NETFILTER
- + NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
- + NFA_SPACE(sizeof(u_int32_t)) /* ifindex */
- #endif
- + NFA_SPACE(sizeof(u_int32_t)) /* mark */
- + NFA_SPACE(sizeof(struct nfqnl_msg_packet_hw))
- + NFA_SPACE(sizeof(struct nfqnl_msg_packet_timestamp));
- outdev = entinf->outdev;
- spin_lock_bh(&queue->lock);
- switch (queue->copy_mode) {
- case NFQNL_COPY_META:
- case NFQNL_COPY_NONE:
- data_len = 0;
- break;
- case NFQNL_COPY_PACKET:
- if ((entskb->ip_summed == CHECKSUM_PARTIAL ||
- entskb->ip_summed == CHECKSUM_COMPLETE) &&
- (*errp = skb_checksum_help(entskb))) {
- spin_unlock_bh(&queue->lock);
- return NULL;
- }
- if (queue->copy_range == 0
- || queue->copy_range > entskb->len)
- data_len = entskb->len;
- else
- data_len = queue->copy_range;
- size += NFA_SPACE(data_len);
- break;
- default:
- *errp = -EINVAL;
- spin_unlock_bh(&queue->lock);
- return NULL;
- }
- spin_unlock_bh(&queue->lock);
- skb = alloc_skb(size, GFP_ATOMIC);
- if (!skb)
- goto nlmsg_failure;
- old_tail= skb->tail;
- nlh = NLMSG_PUT(skb, 0, 0,
- NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
- sizeof(struct nfgenmsg));
- nfmsg = NLMSG_DATA(nlh);
- nfmsg->nfgen_family = entinf->pf;
- nfmsg->version = NFNETLINK_V0;
- nfmsg->res_id = htons(queue->queue_num);
- pmsg.packet_id = htonl(entry->id);
- pmsg.hw_protocol = entskb->protocol;
- pmsg.hook = entinf->hook;
- NFA_PUT(skb, NFQA_PACKET_HDR, sizeof(pmsg), &pmsg);
- indev = entinf->indev;
- if (indev) {
- tmp_uint = htonl(indev->ifindex);
- #ifndef CONFIG_BRIDGE_NETFILTER
- NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint), &tmp_uint);
- #else
- if (entinf->pf == PF_BRIDGE) {
- /* Case 1: indev is physical input device, we need to
- * look for bridge group (when called from
- * netfilter_bridge) */
- NFA_PUT(skb, NFQA_IFINDEX_PHYSINDEV, sizeof(tmp_uint),
- &tmp_uint);
- /* this is the bridge group "brX" */
- tmp_uint = htonl(indev->br_port->br->dev->ifindex);
- NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint),
- &tmp_uint);
- } else {
- /* Case 2: indev is bridge group, we need to look for
- * physical device (when called from ipv4) */
- NFA_PUT(skb, NFQA_IFINDEX_INDEV, sizeof(tmp_uint),
- &tmp_uint);
- if (entskb->nf_bridge
- && entskb->nf_bridge->physindev) {
- tmp_uint = htonl(entskb->nf_bridge->physindev->ifindex);
- NFA_PUT(skb, NFQA_IFINDEX_PHYSINDEV,
- sizeof(tmp_uint), &tmp_uint);
- }
- }
- #endif
- }
- if (outdev) {
- tmp_uint = htonl(outdev->ifindex);
- #ifndef CONFIG_BRIDGE_NETFILTER
- NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint), &tmp_uint);
- #else
- if (entinf->pf == PF_BRIDGE) {
- /* Case 1: outdev is physical output device, we need to
- * look for bridge group (when called from
- * netfilter_bridge) */
- NFA_PUT(skb, NFQA_IFINDEX_PHYSOUTDEV, sizeof(tmp_uint),
- &tmp_uint);
- /* this is the bridge group "brX" */
- tmp_uint = htonl(outdev->br_port->br->dev->ifindex);
- NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint),
- &tmp_uint);
- } else {
- /* Case 2: outdev is bridge group, we need to look for
- * physical output device (when called from ipv4) */
- NFA_PUT(skb, NFQA_IFINDEX_OUTDEV, sizeof(tmp_uint),
- &tmp_uint);
- if (entskb->nf_bridge
- && entskb->nf_bridge->physoutdev) {
- tmp_uint = htonl(entskb->nf_bridge->physoutdev->ifindex);
- NFA_PUT(skb, NFQA_IFINDEX_PHYSOUTDEV,
- sizeof(tmp_uint), &tmp_uint);
- }
- }
- #endif
- }
- if (entskb->mark) {
- tmp_uint = htonl(entskb->mark);
- NFA_PUT(skb, NFQA_MARK, sizeof(u_int32_t), &tmp_uint);
- }
- if (indev && entskb->dev
- && entskb->dev->hard_header_parse) {
- struct nfqnl_msg_packet_hw phw;
- int len = entskb->dev->hard_header_parse(entskb,
- phw.hw_addr);
- phw.hw_addrlen = htons(len);
- NFA_PUT(skb, NFQA_HWADDR, sizeof(phw), &phw);
- }
- if (entskb->tstamp.off_sec) {
- struct nfqnl_msg_packet_timestamp ts;
- ts.sec = cpu_to_be64(entskb->tstamp.off_sec);
- ts.usec = cpu_to_be64(entskb->tstamp.off_usec);
- NFA_PUT(skb, NFQA_TIMESTAMP, sizeof(ts), &ts);
- }
- if (data_len) {
- struct nfattr *nfa;
- int size = NFA_LENGTH(data_len);
- if (skb_tailroom(skb) < (int)NFA_SPACE(data_len)) {
- printk(KERN_WARNING "nf_queue: no tailroom!\n");
- goto nlmsg_failure;
- }
- nfa = (struct nfattr *)skb_put(skb, NFA_ALIGN(size));
- nfa->nfa_type = NFQA_PAYLOAD;
- nfa->nfa_len = size;
- if (skb_copy_bits(entskb, 0, NFA_DATA(nfa), data_len))
- BUG();
- }
- nlh->nlmsg_len = skb->tail - old_tail;
- return skb;
- nlmsg_failure:
- nfattr_failure:
- if (skb)
- kfree_skb(skb);
- *errp = -EINVAL;
- if (net_ratelimit())
- printk(KERN_ERR "nf_queue: error creating packet message\n");
- return NULL;
- }
- static int
- nfqnl_enqueue_packet(struct sk_buff *skb, struct nf_info *info,
- unsigned int queuenum, void *data)
- {
- int status = -EINVAL;
- struct sk_buff *nskb;
- struct nfqnl_instance *queue;
- struct nfqnl_queue_entry *entry;
- QDEBUG("entered\n");
- queue = instance_lookup_get(queuenum);
- if (!queue) {
- QDEBUG("no queue instance matching\n");
- return -EINVAL;
- }
- if (queue->copy_mode == NFQNL_COPY_NONE) {
- QDEBUG("mode COPY_NONE, aborting\n");
- status = -EAGAIN;
- goto err_out_put;
- }
- entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
- if (entry == NULL) {
- if (net_ratelimit())
- printk(KERN_ERR
- "nf_queue: OOM in nfqnl_enqueue_packet()\n");
- status = -ENOMEM;
- goto err_out_put;
- }
- entry->info = info;
- entry->skb = skb;
- entry->id = atomic_inc_return(&queue->id_sequence);
- nskb = nfqnl_build_packet_message(queue, entry, &status);
- if (nskb == NULL)
- goto err_out_free;
- spin_lock_bh(&queue->lock);
- if (!queue->peer_pid)
- goto err_out_free_nskb;
- if (queue->queue_total >= queue->queue_maxlen) {
- queue->queue_dropped++;
- status = -ENOSPC;
- if (net_ratelimit())
- printk(KERN_WARNING "nf_queue: full at %d entries, "
- "dropping packets(s). Dropped: %d\n",
- queue->queue_total, queue->queue_dropped);
- goto err_out_free_nskb;
- }
- /* nfnetlink_unicast will either free the nskb or add it to a socket */
- status = nfnetlink_unicast(nskb, queue->peer_pid, MSG_DONTWAIT);
- if (status < 0) {
- queue->queue_user_dropped++;
- goto err_out_unlock;
- }
- __enqueue_entry(queue, entry);
- spin_unlock_bh(&queue->lock);
- instance_put(queue);
- return status;
- err_out_free_nskb:
- kfree_skb(nskb);
- err_out_unlock:
- spin_unlock_bh(&queue->lock);
- err_out_free:
- kfree(entry);
- err_out_put:
- instance_put(queue);
- return status;
- }
- static int
- nfqnl_mangle(void *data, int data_len, struct nfqnl_queue_entry *e)
- {
- int diff;
- diff = data_len - e->skb->len;
- if (diff < 0) {
- if (pskb_trim(e->skb, data_len))
- return -ENOMEM;
- } else if (diff > 0) {
- if (data_len > 0xFFFF)
- return -EINVAL;
- if (diff > skb_tailroom(e->skb)) {
- struct sk_buff *newskb;
- newskb = skb_copy_expand(e->skb,
- skb_headroom(e->skb),
- diff,
- GFP_ATOMIC);
- if (newskb == NULL) {
- printk(KERN_WARNING "nf_queue: OOM "
- "in mangle, dropping packet\n");
- return -ENOMEM;
- }
- if (e->skb->sk)
- skb_set_owner_w(newskb, e->skb->sk);
- kfree_skb(e->skb);
- e->skb = newskb;
- }
- skb_put(e->skb, diff);
- }
- if (!skb_make_writable(&e->skb, data_len))
- return -ENOMEM;
- memcpy(e->skb->data, data, data_len);
- e->skb->ip_summed = CHECKSUM_NONE;
- return 0;
- }
- static inline int
- id_cmp(struct nfqnl_queue_entry *e, unsigned long id)
- {
- return (id == e->id);
- }
- static int
- nfqnl_set_mode(struct nfqnl_instance *queue,
- unsigned char mode, unsigned int range)
- {
- int status;
- spin_lock_bh(&queue->lock);
- status = __nfqnl_set_mode(queue, mode, range);
- spin_unlock_bh(&queue->lock);
- return status;
- }
- static int
- dev_cmp(struct nfqnl_queue_entry *entry, unsigned long ifindex)
- {
- struct nf_info *entinf = entry->info;
- if (entinf->indev)
- if (entinf->indev->ifindex == ifindex)
- return 1;
- if (entinf->outdev)
- if (entinf->outdev->ifindex == ifindex)
- return 1;
- #ifdef CONFIG_BRIDGE_NETFILTER
- if (entry->skb->nf_bridge) {
- if (entry->skb->nf_bridge->physindev &&
- entry->skb->nf_bridge->physindev->ifindex == ifindex)
- return 1;
- if (entry->skb->nf_bridge->physoutdev &&
- entry->skb->nf_bridge->physoutdev->ifindex == ifindex)
- return 1;
- }
- #endif
- return 0;
- }
- /* drop all packets with either indev or outdev == ifindex from all queue
- * instances */
- static void
- nfqnl_dev_drop(int ifindex)
- {
- int i;
- QDEBUG("entering for ifindex %u\n", ifindex);
- /* this only looks like we have to hold the readlock for a way too long
- * time, issue_verdict(), nf_reinject(), ... - but we always only
- * issue NF_DROP, which is processed directly in nf_reinject() */
- read_lock_bh(&instances_lock);
- for (i = 0; i < INSTANCE_BUCKETS; i++) {
- struct hlist_node *tmp;
- struct nfqnl_instance *inst;
- struct hlist_head *head = &instance_table[i];
- hlist_for_each_entry(inst, tmp, head, hlist) {
- struct nfqnl_queue_entry *entry;
- while ((entry = find_dequeue_entry(inst, dev_cmp,
- ifindex)) != NULL)
- issue_verdict(entry, NF_DROP);
- }
- }
- read_unlock_bh(&instances_lock);
- }
- #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
- static int
- nfqnl_rcv_dev_event(struct notifier_block *this,
- unsigned long event, void *ptr)
- {
- struct net_device *dev = ptr;
- /* Drop any packets associated with the downed device */
- if (event == NETDEV_DOWN)
- nfqnl_dev_drop(dev->ifindex);
- return NOTIFY_DONE;
- }
- static struct notifier_block nfqnl_dev_notifier = {
- .notifier_call = nfqnl_rcv_dev_event,
- };
- static int
- nfqnl_rcv_nl_event(struct notifier_block *this,
- unsigned long event, void *ptr)
- {
- struct netlink_notify *n = ptr;
- if (event == NETLINK_URELEASE &&
- n->protocol == NETLINK_NETFILTER && n->pid) {
- int i;
- /* destroy all instances for this pid */
- write_lock_bh(&instances_lock);
- for (i = 0; i < INSTANCE_BUCKETS; i++) {
- struct hlist_node *tmp, *t2;
- struct nfqnl_instance *inst;
- struct hlist_head *head = &instance_table[i];
- hlist_for_each_entry_safe(inst, tmp, t2, head, hlist) {
- if (n->pid == inst->peer_pid)
- __instance_destroy(inst);
- }
- }
- write_unlock_bh(&instances_lock);
- }
- return NOTIFY_DONE;
- }
- static struct notifier_block nfqnl_rtnl_notifier = {
- .notifier_call = nfqnl_rcv_nl_event,
- };
- static const int nfqa_verdict_min[NFQA_MAX] = {
- [NFQA_VERDICT_HDR-1] = sizeof(struct nfqnl_msg_verdict_hdr),
- [NFQA_MARK-1] = sizeof(u_int32_t),
- [NFQA_PAYLOAD-1] = 0,
- };
- static int
- nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb,
- struct nlmsghdr *nlh, struct nfattr *nfqa[], int *errp)
- {
- struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
- u_int16_t queue_num = ntohs(nfmsg->res_id);
- struct nfqnl_msg_verdict_hdr *vhdr;
- struct nfqnl_instance *queue;
- unsigned int verdict;
- struct nfqnl_queue_entry *entry;
- int err;
- if (nfattr_bad_size(nfqa, NFQA_MAX, nfqa_verdict_min)) {
- QDEBUG("bad attribute size\n");
- return -EINVAL;
- }
- queue = instance_lookup_get(queue_num);
- if (!queue)
- return -ENODEV;
- if (queue->peer_pid != NETLINK_CB(skb).pid) {
- err = -EPERM;
- goto err_out_put;
- }
- if (!nfqa[NFQA_VERDICT_HDR-1]) {
- err = -EINVAL;
- goto err_out_put;
- }
- vhdr = NFA_DATA(nfqa[NFQA_VERDICT_HDR-1]);
- verdict = ntohl(vhdr->verdict);
- if ((verdict & NF_VERDICT_MASK) > NF_MAX_VERDICT) {
- err = -EINVAL;
- goto err_out_put;
- }
- entry = find_dequeue_entry(queue, id_cmp, ntohl(vhdr->id));
- if (entry == NULL) {
- err = -ENOENT;
- goto err_out_put;
- }
- if (nfqa[NFQA_PAYLOAD-1]) {
- if (nfqnl_mangle(NFA_DATA(nfqa[NFQA_PAYLOAD-1]),
- NFA_PAYLOAD(nfqa[NFQA_PAYLOAD-1]), entry) < 0)
- verdict = NF_DROP;
- }
- if (nfqa[NFQA_MARK-1])
- entry->skb->mark = ntohl(*(__be32 *)
- NFA_DATA(nfqa[NFQA_MARK-1]));
- issue_verdict(entry, verdict);
- instance_put(queue);
- return 0;
- err_out_put:
- instance_put(queue);
- return err;
- }
- static int
- nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
- struct nlmsghdr *nlh, struct nfattr *nfqa[], int *errp)
- {
- return -ENOTSUPP;
- }
- static const int nfqa_cfg_min[NFQA_CFG_MAX] = {
- [NFQA_CFG_CMD-1] = sizeof(struct nfqnl_msg_config_cmd),
- [NFQA_CFG_PARAMS-1] = sizeof(struct nfqnl_msg_config_params),
- };
- static struct nf_queue_handler nfqh = {
- .name = "nf_queue",
- .outfn = &nfqnl_enqueue_packet,
- };
- static int
- nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
- struct nlmsghdr *nlh, struct nfattr *nfqa[], int *errp)
- {
- struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
- u_int16_t queue_num = ntohs(nfmsg->res_id);
- struct nfqnl_instance *queue;
- int ret = 0;
- QDEBUG("entering for msg %u\n", NFNL_MSG_TYPE(nlh->nlmsg_type));
- if (nfattr_bad_size(nfqa, NFQA_CFG_MAX, nfqa_cfg_min)) {
- QDEBUG("bad attribute size\n");
- return -EINVAL;
- }
- queue = instance_lookup_get(queue_num);
- if (nfqa[NFQA_CFG_CMD-1]) {
- struct nfqnl_msg_config_cmd *cmd;
- cmd = NFA_DATA(nfqa[NFQA_CFG_CMD-1]);
- QDEBUG("found CFG_CMD\n");
- switch (cmd->command) {
- case NFQNL_CFG_CMD_BIND:
- if (queue)
- return -EBUSY;
- queue = instance_create(queue_num, NETLINK_CB(skb).pid);
- if (!queue)
- return -EINVAL;
- break;
- case NFQNL_CFG_CMD_UNBIND:
- if (!queue)
- return -ENODEV;
- if (queue->peer_pid != NETLINK_CB(skb).pid) {
- ret = -EPERM;
- goto out_put;
- }
- instance_destroy(queue);
- break;
- case NFQNL_CFG_CMD_PF_BIND:
- QDEBUG("registering queue handler for pf=%u\n",
- ntohs(cmd->pf));
- ret = nf_register_queue_handler(ntohs(cmd->pf), &nfqh);
- break;
- case NFQNL_CFG_CMD_PF_UNBIND:
- QDEBUG("unregistering queue handler for pf=%u\n",
- ntohs(cmd->pf));
- /* This is a bug and a feature. We can unregister
- * other handlers(!) */
- ret = nf_unregister_queue_handler(ntohs(cmd->pf));
- break;
- default:
- ret = -EINVAL;
- break;
- }
- } else {
- if (!queue) {
- QDEBUG("no config command, and no instance ENOENT\n");
- ret = -ENOENT;
- goto out_put;
- }
- if (queue->peer_pid != NETLINK_CB(skb).pid) {
- QDEBUG("no config command, and wrong pid\n");
- ret = -EPERM;
- goto out_put;
- }
- }
- if (nfqa[NFQA_CFG_PARAMS-1]) {
- struct nfqnl_msg_config_params *params;
- if (!queue) {
- ret = -ENOENT;
- goto out_put;
- }
- params = NFA_DATA(nfqa[NFQA_CFG_PARAMS-1]);
- nfqnl_set_mode(queue, params->copy_mode,
- ntohl(params->copy_range));
- }
- if (nfqa[NFQA_CFG_QUEUE_MAXLEN-1]) {
- __be32 *queue_maxlen;
- queue_maxlen = NFA_DATA(nfqa[NFQA_CFG_QUEUE_MAXLEN-1]);
- spin_lock_bh(&queue->lock);
- queue->queue_maxlen = ntohl(*queue_maxlen);
- spin_unlock_bh(&queue->lock);
- }
- out_put:
- instance_put(queue);
- return ret;
- }
- static struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = {
- [NFQNL_MSG_PACKET] = { .call = nfqnl_recv_unsupp,
- .attr_count = NFQA_MAX, },
- [NFQNL_MSG_VERDICT] = { .call = nfqnl_recv_verdict,
- .attr_count = NFQA_MAX, },
- [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config,
- .attr_count = NFQA_CFG_MAX, },
- };
- static struct nfnetlink_subsystem nfqnl_subsys = {
- .name = "nf_queue",
- .subsys_id = NFNL_SUBSYS_QUEUE,
- .cb_count = NFQNL_MSG_MAX,
- .cb = nfqnl_cb,
- };
- #ifdef CONFIG_PROC_FS
- struct iter_state {
- unsigned int bucket;
- };
- static struct hlist_node *get_first(struct seq_file *seq)
- {
- struct iter_state *st = seq->private;
- if (!st)
- return NULL;
- for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
- if (!hlist_empty(&instance_table[st->bucket]))
- return instance_table[st->bucket].first;
- }
- return NULL;
- }
- static struct hlist_node *get_next(struct seq_file *seq, struct hlist_node *h)
- {
- struct iter_state *st = seq->private;
- h = h->next;
- while (!h) {
- if (++st->bucket >= INSTANCE_BUCKETS)
- return NULL;
- h = instance_table[st->bucket].first;
- }
- return h;
- }
- static struct hlist_node *get_idx(struct seq_file *seq, loff_t pos)
- {
- struct hlist_node *head;
- head = get_first(seq);
- if (head)
- while (pos && (head = get_next(seq, head)))
- pos--;
- return pos ? NULL : head;
- }
- static void *seq_start(struct seq_file *seq, loff_t *pos)
- {
- read_lock_bh(&instances_lock);
- return get_idx(seq, *pos);
- }
- static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
- {
- (*pos)++;
- return get_next(s, v);
- }
- static void seq_stop(struct seq_file *s, void *v)
- {
- read_unlock_bh(&instances_lock);
- }
- static int seq_show(struct seq_file *s, void *v)
- {
- const struct nfqnl_instance *inst = v;
- return seq_printf(s, "%5d %6d %5d %1d %5d %5d %5d %8d %2d\n",
- inst->queue_num,
- inst->peer_pid, inst->queue_total,
- inst->copy_mode, inst->copy_range,
- inst->queue_dropped, inst->queue_user_dropped,
- atomic_read(&inst->id_sequence),
- atomic_read(&inst->use));
- }
- static struct seq_operations nfqnl_seq_ops = {
- .start = seq_start,
- .next = seq_next,
- .stop = seq_stop,
- .show = seq_show,
- };
- static int nfqnl_open(struct inode *inode, struct file *file)
- {
- struct seq_file *seq;
- struct iter_state *is;
- int ret;
- is = kzalloc(sizeof(*is), GFP_KERNEL);
- if (!is)
- return -ENOMEM;
- ret = seq_open(file, &nfqnl_seq_ops);
- if (ret < 0)
- goto out_free;
- seq = file->private_data;
- seq->private = is;
- return ret;
- out_free:
- kfree(is);
- return ret;
- }
- static const struct file_operations nfqnl_file_ops = {
- .owner = THIS_MODULE,
- .open = nfqnl_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release_private,
- };
- #endif /* PROC_FS */
- static int __init nfnetlink_queue_init(void)
- {
- int i, status = -ENOMEM;
- #ifdef CONFIG_PROC_FS
- struct proc_dir_entry *proc_nfqueue;
- #endif
- for (i = 0; i < INSTANCE_BUCKETS; i++)
- INIT_HLIST_HEAD(&instance_table[i]);
- netlink_register_notifier(&nfqnl_rtnl_notifier);
- status = nfnetlink_subsys_register(&nfqnl_subsys);
- if (status < 0) {
- printk(KERN_ERR "nf_queue: failed to create netlink socket\n");
- goto cleanup_netlink_notifier;
- }
- #ifdef CONFIG_PROC_FS
- proc_nfqueue = create_proc_entry("nfnetlink_queue", 0440,
- proc_net_netfilter);
- if (!proc_nfqueue)
- goto cleanup_subsys;
- proc_nfqueue->proc_fops = &nfqnl_file_ops;
- #endif
- register_netdevice_notifier(&nfqnl_dev_notifier);
- return status;
- #ifdef CONFIG_PROC_FS
- cleanup_subsys:
- nfnetlink_subsys_unregister(&nfqnl_subsys);
- #endif
- cleanup_netlink_notifier:
- netlink_unregister_notifier(&nfqnl_rtnl_notifier);
- return status;
- }
- static void __exit nfnetlink_queue_fini(void)
- {
- nf_unregister_queue_handlers(&nfqh);
- unregister_netdevice_notifier(&nfqnl_dev_notifier);
- #ifdef CONFIG_PROC_FS
- remove_proc_entry("nfnetlink_queue", proc_net_netfilter);
- #endif
- nfnetlink_subsys_unregister(&nfqnl_subsys);
- netlink_unregister_notifier(&nfqnl_rtnl_notifier);
- }
- MODULE_DESCRIPTION("netfilter packet queue handler");
- MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
- MODULE_LICENSE("GPL");
- MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_QUEUE);
- module_init(nfnetlink_queue_init);
- module_exit(nfnetlink_queue_fini);
|