diff options
Diffstat (limited to 'net/netfilter/nfnetlink_queue_core.c')
-rw-r--r-- | net/netfilter/nfnetlink_queue_core.c | 1416 |
1 files changed, 0 insertions, 1416 deletions
diff --git a/net/netfilter/nfnetlink_queue_core.c b/net/netfilter/nfnetlink_queue_core.c deleted file mode 100644 index a5cd6d90b..000000000 --- a/net/netfilter/nfnetlink_queue_core.c +++ /dev/null @@ -1,1416 +0,0 @@ -/* - * This is a module which is used for queueing packets and communicating with - * userspace via nfnetlink. - * - * (C) 2005 by Harald Welte <laforge@netfilter.org> - * (C) 2007 by Patrick McHardy <kaber@trash.net> - * - * 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/slab.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_bridge.h> -#include <linux/netfilter/nfnetlink.h> -#include <linux/netfilter/nfnetlink_queue.h> -#include <linux/list.h> -#include <net/sock.h> -#include <net/tcp_states.h> -#include <net/netfilter/nf_queue.h> -#include <net/netns/generic.h> -#include <net/netfilter/nfnetlink_queue.h> - -#include <linux/atomic.h> - -#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) -#include "../bridge/br_private.h" -#endif - -#define NFQNL_QMAX_DEFAULT 1024 - -/* We're using struct nlattr which has 16bit nla_len. Note that nla_len - * includes the header length. Thus, the maximum packet length that we - * support is 65531 bytes. We send truncated packets if the specified length - * is larger than that. Userspace can check for presence of NFQA_CAP_LEN - * attribute to detect truncation. - */ -#define NFQNL_MAX_COPY_RANGE (0xffff - NLA_HDRLEN) - -struct nfqnl_instance { - struct hlist_node hlist; /* global list of queues */ - struct rcu_head rcu; - - u32 peer_portid; - unsigned int queue_maxlen; - unsigned int copy_range; - unsigned int queue_dropped; - unsigned int queue_user_dropped; - - - u_int16_t queue_num; /* number of this queue */ - u_int8_t copy_mode; - u_int32_t flags; /* Set using NFQA_CFG_FLAGS */ -/* - * Following fields are dirtied for each queued packet, - * keep them in same cache line if possible. - */ - spinlock_t lock; - unsigned int queue_total; - unsigned int id_sequence; /* 'sequence' of pkt ids */ - struct list_head queue_list; /* packets in queue */ -}; - -typedef int (*nfqnl_cmpfn)(struct nf_queue_entry *, unsigned long); - -static int nfnl_queue_net_id __read_mostly; - -#define INSTANCE_BUCKETS 16 -struct nfnl_queue_net { - spinlock_t instances_lock; - struct hlist_head instance_table[INSTANCE_BUCKETS]; -}; - -static struct nfnl_queue_net *nfnl_queue_pernet(struct net *net) -{ - return net_generic(net, nfnl_queue_net_id); -} - -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(struct nfnl_queue_net *q, u_int16_t queue_num) -{ - struct hlist_head *head; - struct nfqnl_instance *inst; - - head = &q->instance_table[instance_hashfn(queue_num)]; - hlist_for_each_entry_rcu(inst, head, hlist) { - if (inst->queue_num == queue_num) - return inst; - } - return NULL; -} - -static struct nfqnl_instance * -instance_create(struct nfnl_queue_net *q, u_int16_t queue_num, u32 portid) -{ - struct nfqnl_instance *inst; - unsigned int h; - int err; - - spin_lock(&q->instances_lock); - if (instance_lookup(q, queue_num)) { - err = -EEXIST; - goto out_unlock; - } - - inst = kzalloc(sizeof(*inst), GFP_ATOMIC); - if (!inst) { - err = -ENOMEM; - goto out_unlock; - } - - inst->queue_num = queue_num; - inst->peer_portid = portid; - inst->queue_maxlen = NFQNL_QMAX_DEFAULT; - inst->copy_range = NFQNL_MAX_COPY_RANGE; - inst->copy_mode = NFQNL_COPY_NONE; - spin_lock_init(&inst->lock); - INIT_LIST_HEAD(&inst->queue_list); - - if (!try_module_get(THIS_MODULE)) { - err = -EAGAIN; - goto out_free; - } - - h = instance_hashfn(queue_num); - hlist_add_head_rcu(&inst->hlist, &q->instance_table[h]); - - spin_unlock(&q->instances_lock); - - return inst; - -out_free: - kfree(inst); -out_unlock: - spin_unlock(&q->instances_lock); - return ERR_PTR(err); -} - -static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, - unsigned long data); - -static void -instance_destroy_rcu(struct rcu_head *head) -{ - struct nfqnl_instance *inst = container_of(head, struct nfqnl_instance, - rcu); - - nfqnl_flush(inst, NULL, 0); - kfree(inst); - module_put(THIS_MODULE); -} - -static void -__instance_destroy(struct nfqnl_instance *inst) -{ - hlist_del_rcu(&inst->hlist); - call_rcu(&inst->rcu, instance_destroy_rcu); -} - -static void -instance_destroy(struct nfnl_queue_net *q, struct nfqnl_instance *inst) -{ - spin_lock(&q->instances_lock); - __instance_destroy(inst); - spin_unlock(&q->instances_lock); -} - -static inline void -__enqueue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry) -{ - list_add_tail(&entry->list, &queue->queue_list); - queue->queue_total++; -} - -static void -__dequeue_entry(struct nfqnl_instance *queue, struct nf_queue_entry *entry) -{ - list_del(&entry->list); - queue->queue_total--; -} - -static struct nf_queue_entry * -find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id) -{ - struct nf_queue_entry *entry = NULL, *i; - - spin_lock_bh(&queue->lock); - - list_for_each_entry(i, &queue->queue_list, list) { - if (i->id == id) { - entry = i; - break; - } - } - - if (entry) - __dequeue_entry(queue, entry); - - spin_unlock_bh(&queue->lock); - - return entry; -} - -static void -nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data) -{ - struct nf_queue_entry *entry, *next; - - spin_lock_bh(&queue->lock); - list_for_each_entry_safe(entry, next, &queue->queue_list, list) { - if (!cmpfn || cmpfn(entry, data)) { - list_del(&entry->list); - queue->queue_total--; - nf_reinject(entry, NF_DROP); - } - } - spin_unlock_bh(&queue->lock); -} - -static int -nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet, - bool csum_verify) -{ - __u32 flags = 0; - - if (packet->ip_summed == CHECKSUM_PARTIAL) - flags = NFQA_SKB_CSUMNOTREADY; - else if (csum_verify) - flags = NFQA_SKB_CSUM_NOTVERIFIED; - - if (skb_is_gso(packet)) - flags |= NFQA_SKB_GSO; - - return flags ? nla_put_be32(nlskb, NFQA_SKB_INFO, htonl(flags)) : 0; -} - -static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk) -{ - const struct cred *cred; - - if (!sk_fullsock(sk)) - return 0; - - read_lock_bh(&sk->sk_callback_lock); - if (sk->sk_socket && sk->sk_socket->file) { - cred = sk->sk_socket->file->f_cred; - if (nla_put_be32(skb, NFQA_UID, - htonl(from_kuid_munged(&init_user_ns, cred->fsuid)))) - goto nla_put_failure; - if (nla_put_be32(skb, NFQA_GID, - htonl(from_kgid_munged(&init_user_ns, cred->fsgid)))) - goto nla_put_failure; - } - read_unlock_bh(&sk->sk_callback_lock); - return 0; - -nla_put_failure: - read_unlock_bh(&sk->sk_callback_lock); - return -1; -} - -static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata) -{ - u32 seclen = 0; -#if IS_ENABLED(CONFIG_NETWORK_SECMARK) - if (!skb || !sk_fullsock(skb->sk)) - return 0; - - read_lock_bh(&skb->sk->sk_callback_lock); - - if (skb->secmark) - security_secid_to_secctx(skb->secmark, secdata, &seclen); - - read_unlock_bh(&skb->sk->sk_callback_lock); -#endif - return seclen; -} - -static struct sk_buff * -nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue, - struct nf_queue_entry *entry, - __be32 **packet_id_ptr) -{ - size_t size; - size_t data_len = 0, cap_len = 0, rem_len = 0; - unsigned int hlen = 0; - struct sk_buff *skb; - struct nlattr *nla; - struct nfqnl_msg_packet_hdr *pmsg; - struct nlmsghdr *nlh; - struct nfgenmsg *nfmsg; - struct sk_buff *entskb = entry->skb; - struct net_device *indev; - struct net_device *outdev; - struct nf_conn *ct = NULL; - enum ip_conntrack_info uninitialized_var(ctinfo); - bool csum_verify; - char *secdata = NULL; - u32 seclen = 0; - - size = nlmsg_total_size(sizeof(struct nfgenmsg)) - + nla_total_size(sizeof(struct nfqnl_msg_packet_hdr)) - + nla_total_size(sizeof(u_int32_t)) /* ifindex */ - + nla_total_size(sizeof(u_int32_t)) /* ifindex */ -#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - + nla_total_size(sizeof(u_int32_t)) /* ifindex */ - + nla_total_size(sizeof(u_int32_t)) /* ifindex */ -#endif - + nla_total_size(sizeof(u_int32_t)) /* mark */ - + nla_total_size(sizeof(struct nfqnl_msg_packet_hw)) - + nla_total_size(sizeof(u_int32_t)) /* skbinfo */ - + nla_total_size(sizeof(u_int32_t)); /* cap_len */ - - if (entskb->tstamp.tv64) - size += nla_total_size(sizeof(struct nfqnl_msg_packet_timestamp)); - - if (entry->state.hook <= NF_INET_FORWARD || - (entry->state.hook == NF_INET_POST_ROUTING && entskb->sk == NULL)) - csum_verify = !skb_csum_unnecessary(entskb); - else - csum_verify = false; - - outdev = entry->state.out; - - switch ((enum nfqnl_config_mode)ACCESS_ONCE(queue->copy_mode)) { - case NFQNL_COPY_META: - case NFQNL_COPY_NONE: - break; - - case NFQNL_COPY_PACKET: - if (!(queue->flags & NFQA_CFG_F_GSO) && - entskb->ip_summed == CHECKSUM_PARTIAL && - skb_checksum_help(entskb)) - return NULL; - - data_len = ACCESS_ONCE(queue->copy_range); - if (data_len > entskb->len) - data_len = entskb->len; - - hlen = skb_zerocopy_headlen(entskb); - hlen = min_t(unsigned int, hlen, data_len); - size += sizeof(struct nlattr) + hlen; - cap_len = entskb->len; - rem_len = data_len - hlen; - break; - } - - if (queue->flags & NFQA_CFG_F_CONNTRACK) - ct = nfqnl_ct_get(entskb, &size, &ctinfo); - - if (queue->flags & NFQA_CFG_F_UID_GID) { - size += (nla_total_size(sizeof(u_int32_t)) /* uid */ - + nla_total_size(sizeof(u_int32_t))); /* gid */ - } - - if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) { - seclen = nfqnl_get_sk_secctx(entskb, &secdata); - if (seclen) - size += nla_total_size(seclen); - } - - skb = __netlink_alloc_skb(net->nfnl, size, rem_len, queue->peer_portid, - GFP_ATOMIC); - if (!skb) { - skb_tx_error(entskb); - return NULL; - } - - nlh = nlmsg_put(skb, 0, 0, - NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET, - sizeof(struct nfgenmsg), 0); - if (!nlh) { - skb_tx_error(entskb); - kfree_skb(skb); - return NULL; - } - nfmsg = nlmsg_data(nlh); - nfmsg->nfgen_family = entry->state.pf; - nfmsg->version = NFNETLINK_V0; - nfmsg->res_id = htons(queue->queue_num); - - nla = __nla_reserve(skb, NFQA_PACKET_HDR, sizeof(*pmsg)); - pmsg = nla_data(nla); - pmsg->hw_protocol = entskb->protocol; - pmsg->hook = entry->state.hook; - *packet_id_ptr = &pmsg->packet_id; - - indev = entry->state.in; - if (indev) { -#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, htonl(indev->ifindex))) - goto nla_put_failure; -#else - if (entry->state.pf == PF_BRIDGE) { - /* Case 1: indev is physical input device, we need to - * look for bridge group (when called from - * netfilter_bridge) */ - if (nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV, - htonl(indev->ifindex)) || - /* this is the bridge group "brX" */ - /* rcu_read_lock()ed by __nf_queue */ - nla_put_be32(skb, NFQA_IFINDEX_INDEV, - htonl(br_port_get_rcu(indev)->br->dev->ifindex))) - goto nla_put_failure; - } else { - int physinif; - - /* Case 2: indev is bridge group, we need to look for - * physical device (when called from ipv4) */ - if (nla_put_be32(skb, NFQA_IFINDEX_INDEV, - htonl(indev->ifindex))) - goto nla_put_failure; - - physinif = nf_bridge_get_physinif(entskb); - if (physinif && - nla_put_be32(skb, NFQA_IFINDEX_PHYSINDEV, - htonl(physinif))) - goto nla_put_failure; - } -#endif - } - - if (outdev) { -#if !IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, htonl(outdev->ifindex))) - goto nla_put_failure; -#else - if (entry->state.pf == PF_BRIDGE) { - /* Case 1: outdev is physical output device, we need to - * look for bridge group (when called from - * netfilter_bridge) */ - if (nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV, - htonl(outdev->ifindex)) || - /* this is the bridge group "brX" */ - /* rcu_read_lock()ed by __nf_queue */ - nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, - htonl(br_port_get_rcu(outdev)->br->dev->ifindex))) - goto nla_put_failure; - } else { - int physoutif; - - /* Case 2: outdev is bridge group, we need to look for - * physical output device (when called from ipv4) */ - if (nla_put_be32(skb, NFQA_IFINDEX_OUTDEV, - htonl(outdev->ifindex))) - goto nla_put_failure; - - physoutif = nf_bridge_get_physoutif(entskb); - if (physoutif && - nla_put_be32(skb, NFQA_IFINDEX_PHYSOUTDEV, - htonl(physoutif))) - goto nla_put_failure; - } -#endif - } - - if (entskb->mark && - nla_put_be32(skb, NFQA_MARK, htonl(entskb->mark))) - goto nla_put_failure; - - if (indev && entskb->dev && - entskb->mac_header != entskb->network_header) { - struct nfqnl_msg_packet_hw phw; - int len; - - memset(&phw, 0, sizeof(phw)); - len = dev_parse_header(entskb, phw.hw_addr); - if (len) { - phw.hw_addrlen = htons(len); - if (nla_put(skb, NFQA_HWADDR, sizeof(phw), &phw)) - goto nla_put_failure; - } - } - - if (entskb->tstamp.tv64) { - struct nfqnl_msg_packet_timestamp ts; - struct timeval tv = ktime_to_timeval(entskb->tstamp); - ts.sec = cpu_to_be64(tv.tv_sec); - ts.usec = cpu_to_be64(tv.tv_usec); - - if (nla_put(skb, NFQA_TIMESTAMP, sizeof(ts), &ts)) - goto nla_put_failure; - } - - if ((queue->flags & NFQA_CFG_F_UID_GID) && entskb->sk && - nfqnl_put_sk_uidgid(skb, entskb->sk) < 0) - goto nla_put_failure; - - if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata)) - goto nla_put_failure; - - if (ct && nfqnl_ct_put(skb, ct, ctinfo) < 0) - goto nla_put_failure; - - if (cap_len > data_len && - nla_put_be32(skb, NFQA_CAP_LEN, htonl(cap_len))) - goto nla_put_failure; - - if (nfqnl_put_packet_info(skb, entskb, csum_verify)) - goto nla_put_failure; - - if (data_len) { - struct nlattr *nla; - - if (skb_tailroom(skb) < sizeof(*nla) + hlen) - goto nla_put_failure; - - nla = (struct nlattr *)skb_put(skb, sizeof(*nla)); - nla->nla_type = NFQA_PAYLOAD; - nla->nla_len = nla_attr_size(data_len); - - if (skb_zerocopy(skb, entskb, data_len, hlen)) - goto nla_put_failure; - } - - nlh->nlmsg_len = skb->len; - return skb; - -nla_put_failure: - skb_tx_error(entskb); - kfree_skb(skb); - net_err_ratelimited("nf_queue: error creating packet message\n"); - return NULL; -} - -static int -__nfqnl_enqueue_packet(struct net *net, struct nfqnl_instance *queue, - struct nf_queue_entry *entry) -{ - struct sk_buff *nskb; - int err = -ENOBUFS; - __be32 *packet_id_ptr; - int failopen = 0; - - nskb = nfqnl_build_packet_message(net, queue, entry, &packet_id_ptr); - if (nskb == NULL) { - err = -ENOMEM; - goto err_out; - } - spin_lock_bh(&queue->lock); - - if (queue->queue_total >= queue->queue_maxlen) { - if (queue->flags & NFQA_CFG_F_FAIL_OPEN) { - failopen = 1; - err = 0; - } else { - queue->queue_dropped++; - net_warn_ratelimited("nf_queue: full at %d entries, dropping packets(s)\n", - queue->queue_total); - } - goto err_out_free_nskb; - } - entry->id = ++queue->id_sequence; - *packet_id_ptr = htonl(entry->id); - - /* nfnetlink_unicast will either free the nskb or add it to a socket */ - err = nfnetlink_unicast(nskb, net, queue->peer_portid, MSG_DONTWAIT); - if (err < 0) { - queue->queue_user_dropped++; - goto err_out_unlock; - } - - __enqueue_entry(queue, entry); - - spin_unlock_bh(&queue->lock); - return 0; - -err_out_free_nskb: - kfree_skb(nskb); -err_out_unlock: - spin_unlock_bh(&queue->lock); - if (failopen) - nf_reinject(entry, NF_ACCEPT); -err_out: - return err; -} - -static struct nf_queue_entry * -nf_queue_entry_dup(struct nf_queue_entry *e) -{ - struct nf_queue_entry *entry = kmemdup(e, e->size, GFP_ATOMIC); - if (entry) { - if (nf_queue_entry_get_refs(entry)) - return entry; - kfree(entry); - } - return NULL; -} - -#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) -/* When called from bridge netfilter, skb->data must point to MAC header - * before calling skb_gso_segment(). Else, original MAC header is lost - * and segmented skbs will be sent to wrong destination. - */ -static void nf_bridge_adjust_skb_data(struct sk_buff *skb) -{ - if (skb->nf_bridge) - __skb_push(skb, skb->network_header - skb->mac_header); -} - -static void nf_bridge_adjust_segmented_data(struct sk_buff *skb) -{ - if (skb->nf_bridge) - __skb_pull(skb, skb->network_header - skb->mac_header); -} -#else -#define nf_bridge_adjust_skb_data(s) do {} while (0) -#define nf_bridge_adjust_segmented_data(s) do {} while (0) -#endif - -static void free_entry(struct nf_queue_entry *entry) -{ - nf_queue_entry_release_refs(entry); - kfree(entry); -} - -static int -__nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue, - struct sk_buff *skb, struct nf_queue_entry *entry) -{ - int ret = -ENOMEM; - struct nf_queue_entry *entry_seg; - - nf_bridge_adjust_segmented_data(skb); - - if (skb->next == NULL) { /* last packet, no need to copy entry */ - struct sk_buff *gso_skb = entry->skb; - entry->skb = skb; - ret = __nfqnl_enqueue_packet(net, queue, entry); - if (ret) - entry->skb = gso_skb; - return ret; - } - - skb->next = NULL; - - entry_seg = nf_queue_entry_dup(entry); - if (entry_seg) { - entry_seg->skb = skb; - ret = __nfqnl_enqueue_packet(net, queue, entry_seg); - if (ret) - free_entry(entry_seg); - } - return ret; -} - -static int -nfqnl_enqueue_packet(struct nf_queue_entry *entry, unsigned int queuenum) -{ - unsigned int queued; - struct nfqnl_instance *queue; - struct sk_buff *skb, *segs; - int err = -ENOBUFS; - struct net *net = dev_net(entry->state.in ? - entry->state.in : entry->state.out); - struct nfnl_queue_net *q = nfnl_queue_pernet(net); - - /* rcu_read_lock()ed by nf_hook_slow() */ - queue = instance_lookup(q, queuenum); - if (!queue) - return -ESRCH; - - if (queue->copy_mode == NFQNL_COPY_NONE) - return -EINVAL; - - skb = entry->skb; - - switch (entry->state.pf) { - case NFPROTO_IPV4: - skb->protocol = htons(ETH_P_IP); - break; - case NFPROTO_IPV6: - skb->protocol = htons(ETH_P_IPV6); - break; - } - - if ((queue->flags & NFQA_CFG_F_GSO) || !skb_is_gso(skb)) - return __nfqnl_enqueue_packet(net, queue, entry); - - nf_bridge_adjust_skb_data(skb); - segs = skb_gso_segment(skb, 0); - /* Does not use PTR_ERR to limit the number of error codes that can be - * returned by nf_queue. For instance, callers rely on -ECANCELED to - * mean 'ignore this hook'. - */ - if (IS_ERR_OR_NULL(segs)) - goto out_err; - queued = 0; - err = 0; - do { - struct sk_buff *nskb = segs->next; - if (err == 0) - err = __nfqnl_enqueue_packet_gso(net, queue, - segs, entry); - if (err == 0) - queued++; - else - kfree_skb(segs); - segs = nskb; - } while (segs); - - if (queued) { - if (err) /* some segments are already queued */ - free_entry(entry); - kfree_skb(skb); - return 0; - } - out_err: - nf_bridge_adjust_segmented_data(skb); - return err; -} - -static int -nfqnl_mangle(void *data, int data_len, struct nf_queue_entry *e, int diff) -{ - struct sk_buff *nskb; - - 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)) { - nskb = skb_copy_expand(e->skb, skb_headroom(e->skb), - diff, GFP_ATOMIC); - if (!nskb) { - printk(KERN_WARNING "nf_queue: OOM " - "in mangle, dropping packet\n"); - return -ENOMEM; - } - kfree_skb(e->skb); - e->skb = nskb; - } - skb_put(e->skb, diff); - } - if (!skb_make_writable(e->skb, data_len)) - return -ENOMEM; - skb_copy_to_linear_data(e->skb, data, data_len); - e->skb->ip_summed = CHECKSUM_NONE; - return 0; -} - -static int -nfqnl_set_mode(struct nfqnl_instance *queue, - unsigned char mode, unsigned int range) -{ - int status = 0; - - spin_lock_bh(&queue->lock); - 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; - if (range == 0 || range > NFQNL_MAX_COPY_RANGE) - queue->copy_range = NFQNL_MAX_COPY_RANGE; - else - queue->copy_range = range; - break; - - default: - status = -EINVAL; - - } - spin_unlock_bh(&queue->lock); - - return status; -} - -static int -dev_cmp(struct nf_queue_entry *entry, unsigned long ifindex) -{ - if (entry->state.in) - if (entry->state.in->ifindex == ifindex) - return 1; - if (entry->state.out) - if (entry->state.out->ifindex == ifindex) - return 1; -#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - if (entry->skb->nf_bridge) { - int physinif, physoutif; - - physinif = nf_bridge_get_physinif(entry->skb); - physoutif = nf_bridge_get_physoutif(entry->skb); - - if (physinif == ifindex || physoutif == ifindex) - return 1; - } -#endif - return 0; -} - -/* drop all packets with either indev or outdev == ifindex from all queue - * instances */ -static void -nfqnl_dev_drop(struct net *net, int ifindex) -{ - int i; - struct nfnl_queue_net *q = nfnl_queue_pernet(net); - - rcu_read_lock(); - - for (i = 0; i < INSTANCE_BUCKETS; i++) { - struct nfqnl_instance *inst; - struct hlist_head *head = &q->instance_table[i]; - - hlist_for_each_entry_rcu(inst, head, hlist) - nfqnl_flush(inst, dev_cmp, ifindex); - } - - rcu_read_unlock(); -} - -static int -nfqnl_rcv_dev_event(struct notifier_block *this, - unsigned long event, void *ptr) -{ - struct net_device *dev = netdev_notifier_info_to_dev(ptr); - - /* Drop any packets associated with the downed device */ - if (event == NETDEV_DOWN) - nfqnl_dev_drop(dev_net(dev), dev->ifindex); - return NOTIFY_DONE; -} - -static struct notifier_block nfqnl_dev_notifier = { - .notifier_call = nfqnl_rcv_dev_event, -}; - -static int nf_hook_cmp(struct nf_queue_entry *entry, unsigned long ops_ptr) -{ - return entry->elem == (struct nf_hook_ops *)ops_ptr; -} - -static void nfqnl_nf_hook_drop(struct net *net, struct nf_hook_ops *hook) -{ - struct nfnl_queue_net *q = nfnl_queue_pernet(net); - int i; - - rcu_read_lock(); - for (i = 0; i < INSTANCE_BUCKETS; i++) { - struct nfqnl_instance *inst; - struct hlist_head *head = &q->instance_table[i]; - - hlist_for_each_entry_rcu(inst, head, hlist) - nfqnl_flush(inst, nf_hook_cmp, (unsigned long)hook); - } - rcu_read_unlock(); -} - -static int -nfqnl_rcv_nl_event(struct notifier_block *this, - unsigned long event, void *ptr) -{ - struct netlink_notify *n = ptr; - struct nfnl_queue_net *q = nfnl_queue_pernet(n->net); - - if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) { - int i; - - /* destroy all instances for this portid */ - spin_lock(&q->instances_lock); - for (i = 0; i < INSTANCE_BUCKETS; i++) { - struct hlist_node *t2; - struct nfqnl_instance *inst; - struct hlist_head *head = &q->instance_table[i]; - - hlist_for_each_entry_safe(inst, t2, head, hlist) { - if (n->portid == inst->peer_portid) - __instance_destroy(inst); - } - } - spin_unlock(&q->instances_lock); - } - return NOTIFY_DONE; -} - -static struct notifier_block nfqnl_rtnl_notifier = { - .notifier_call = nfqnl_rcv_nl_event, -}; - -static const struct nla_policy nfqa_verdict_policy[NFQA_MAX+1] = { - [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) }, - [NFQA_MARK] = { .type = NLA_U32 }, - [NFQA_PAYLOAD] = { .type = NLA_UNSPEC }, - [NFQA_CT] = { .type = NLA_UNSPEC }, - [NFQA_EXP] = { .type = NLA_UNSPEC }, -}; - -static const struct nla_policy nfqa_verdict_batch_policy[NFQA_MAX+1] = { - [NFQA_VERDICT_HDR] = { .len = sizeof(struct nfqnl_msg_verdict_hdr) }, - [NFQA_MARK] = { .type = NLA_U32 }, -}; - -static struct nfqnl_instance * -verdict_instance_lookup(struct nfnl_queue_net *q, u16 queue_num, u32 nlportid) -{ - struct nfqnl_instance *queue; - - queue = instance_lookup(q, queue_num); - if (!queue) - return ERR_PTR(-ENODEV); - - if (queue->peer_portid != nlportid) - return ERR_PTR(-EPERM); - - return queue; -} - -static struct nfqnl_msg_verdict_hdr* -verdicthdr_get(const struct nlattr * const nfqa[]) -{ - struct nfqnl_msg_verdict_hdr *vhdr; - unsigned int verdict; - - if (!nfqa[NFQA_VERDICT_HDR]) - return NULL; - - vhdr = nla_data(nfqa[NFQA_VERDICT_HDR]); - verdict = ntohl(vhdr->verdict) & NF_VERDICT_MASK; - if (verdict > NF_MAX_VERDICT || verdict == NF_STOLEN) - return NULL; - return vhdr; -} - -static int nfq_id_after(unsigned int id, unsigned int max) -{ - return (int)(id - max) > 0; -} - -static int -nfqnl_recv_verdict_batch(struct sock *ctnl, struct sk_buff *skb, - const struct nlmsghdr *nlh, - const struct nlattr * const nfqa[]) -{ - struct nfgenmsg *nfmsg = nlmsg_data(nlh); - struct nf_queue_entry *entry, *tmp; - unsigned int verdict, maxid; - struct nfqnl_msg_verdict_hdr *vhdr; - struct nfqnl_instance *queue; - LIST_HEAD(batch_list); - u16 queue_num = ntohs(nfmsg->res_id); - - struct net *net = sock_net(ctnl); - struct nfnl_queue_net *q = nfnl_queue_pernet(net); - - queue = verdict_instance_lookup(q, queue_num, - NETLINK_CB(skb).portid); - if (IS_ERR(queue)) - return PTR_ERR(queue); - - vhdr = verdicthdr_get(nfqa); - if (!vhdr) - return -EINVAL; - - verdict = ntohl(vhdr->verdict); - maxid = ntohl(vhdr->id); - - spin_lock_bh(&queue->lock); - - list_for_each_entry_safe(entry, tmp, &queue->queue_list, list) { - if (nfq_id_after(entry->id, maxid)) - break; - __dequeue_entry(queue, entry); - list_add_tail(&entry->list, &batch_list); - } - - spin_unlock_bh(&queue->lock); - - if (list_empty(&batch_list)) - return -ENOENT; - - list_for_each_entry_safe(entry, tmp, &batch_list, list) { - if (nfqa[NFQA_MARK]) - entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK])); - nf_reinject(entry, verdict); - } - return 0; -} - -static int -nfqnl_recv_verdict(struct sock *ctnl, struct sk_buff *skb, - const struct nlmsghdr *nlh, - const struct nlattr * const nfqa[]) -{ - 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 nf_queue_entry *entry; - enum ip_conntrack_info uninitialized_var(ctinfo); - struct nf_conn *ct = NULL; - - struct net *net = sock_net(ctnl); - struct nfnl_queue_net *q = nfnl_queue_pernet(net); - - queue = instance_lookup(q, queue_num); - if (!queue) - queue = verdict_instance_lookup(q, queue_num, - NETLINK_CB(skb).portid); - if (IS_ERR(queue)) - return PTR_ERR(queue); - - vhdr = verdicthdr_get(nfqa); - if (!vhdr) - return -EINVAL; - - verdict = ntohl(vhdr->verdict); - - entry = find_dequeue_entry(queue, ntohl(vhdr->id)); - if (entry == NULL) - return -ENOENT; - - if (nfqa[NFQA_CT]) { - ct = nfqnl_ct_parse(entry->skb, nfqa[NFQA_CT], &ctinfo); - if (ct && nfqa[NFQA_EXP]) { - nfqnl_attach_expect(ct, nfqa[NFQA_EXP], - NETLINK_CB(skb).portid, - nlmsg_report(nlh)); - } - } - - if (nfqa[NFQA_PAYLOAD]) { - u16 payload_len = nla_len(nfqa[NFQA_PAYLOAD]); - int diff = payload_len - entry->skb->len; - - if (nfqnl_mangle(nla_data(nfqa[NFQA_PAYLOAD]), - payload_len, entry, diff) < 0) - verdict = NF_DROP; - - if (ct) - nfqnl_ct_seq_adjust(entry->skb, ct, ctinfo, diff); - } - - if (nfqa[NFQA_MARK]) - entry->skb->mark = ntohl(nla_get_be32(nfqa[NFQA_MARK])); - - nf_reinject(entry, verdict); - return 0; -} - -static int -nfqnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb, - const struct nlmsghdr *nlh, - const struct nlattr * const nfqa[]) -{ - return -ENOTSUPP; -} - -static const struct nla_policy nfqa_cfg_policy[NFQA_CFG_MAX+1] = { - [NFQA_CFG_CMD] = { .len = sizeof(struct nfqnl_msg_config_cmd) }, - [NFQA_CFG_PARAMS] = { .len = sizeof(struct nfqnl_msg_config_params) }, -}; - -static const struct nf_queue_handler nfqh = { - .outfn = &nfqnl_enqueue_packet, - .nf_hook_drop = &nfqnl_nf_hook_drop, -}; - -static int -nfqnl_recv_config(struct sock *ctnl, struct sk_buff *skb, - const struct nlmsghdr *nlh, - const struct nlattr * const nfqa[]) -{ - struct nfgenmsg *nfmsg = nlmsg_data(nlh); - u_int16_t queue_num = ntohs(nfmsg->res_id); - struct nfqnl_instance *queue; - struct nfqnl_msg_config_cmd *cmd = NULL; - struct net *net = sock_net(ctnl); - struct nfnl_queue_net *q = nfnl_queue_pernet(net); - int ret = 0; - - if (nfqa[NFQA_CFG_CMD]) { - cmd = nla_data(nfqa[NFQA_CFG_CMD]); - - /* Obsolete commands without queue context */ - switch (cmd->command) { - case NFQNL_CFG_CMD_PF_BIND: return 0; - case NFQNL_CFG_CMD_PF_UNBIND: return 0; - } - } - - rcu_read_lock(); - queue = instance_lookup(q, queue_num); - if (queue && queue->peer_portid != NETLINK_CB(skb).portid) { - ret = -EPERM; - goto err_out_unlock; - } - - if (cmd != NULL) { - switch (cmd->command) { - case NFQNL_CFG_CMD_BIND: - if (queue) { - ret = -EBUSY; - goto err_out_unlock; - } - queue = instance_create(q, queue_num, - NETLINK_CB(skb).portid); - if (IS_ERR(queue)) { - ret = PTR_ERR(queue); - goto err_out_unlock; - } - break; - case NFQNL_CFG_CMD_UNBIND: - if (!queue) { - ret = -ENODEV; - goto err_out_unlock; - } - instance_destroy(q, queue); - break; - case NFQNL_CFG_CMD_PF_BIND: - case NFQNL_CFG_CMD_PF_UNBIND: - break; - default: - ret = -ENOTSUPP; - break; - } - } - - if (nfqa[NFQA_CFG_PARAMS]) { - struct nfqnl_msg_config_params *params; - - if (!queue) { - ret = -ENODEV; - goto err_out_unlock; - } - params = nla_data(nfqa[NFQA_CFG_PARAMS]); - nfqnl_set_mode(queue, params->copy_mode, - ntohl(params->copy_range)); - } - - if (nfqa[NFQA_CFG_QUEUE_MAXLEN]) { - __be32 *queue_maxlen; - - if (!queue) { - ret = -ENODEV; - goto err_out_unlock; - } - queue_maxlen = nla_data(nfqa[NFQA_CFG_QUEUE_MAXLEN]); - spin_lock_bh(&queue->lock); - queue->queue_maxlen = ntohl(*queue_maxlen); - spin_unlock_bh(&queue->lock); - } - - if (nfqa[NFQA_CFG_FLAGS]) { - __u32 flags, mask; - - if (!queue) { - ret = -ENODEV; - goto err_out_unlock; - } - - if (!nfqa[NFQA_CFG_MASK]) { - /* A mask is needed to specify which flags are being - * changed. - */ - ret = -EINVAL; - goto err_out_unlock; - } - - flags = ntohl(nla_get_be32(nfqa[NFQA_CFG_FLAGS])); - mask = ntohl(nla_get_be32(nfqa[NFQA_CFG_MASK])); - - if (flags >= NFQA_CFG_F_MAX) { - ret = -EOPNOTSUPP; - goto err_out_unlock; - } -#if !IS_ENABLED(CONFIG_NETWORK_SECMARK) - if (flags & mask & NFQA_CFG_F_SECCTX) { - ret = -EOPNOTSUPP; - goto err_out_unlock; - } -#endif - spin_lock_bh(&queue->lock); - queue->flags &= ~mask; - queue->flags |= flags & mask; - spin_unlock_bh(&queue->lock); - } - -err_out_unlock: - rcu_read_unlock(); - return ret; -} - -static const struct nfnl_callback nfqnl_cb[NFQNL_MSG_MAX] = { - [NFQNL_MSG_PACKET] = { .call_rcu = nfqnl_recv_unsupp, - .attr_count = NFQA_MAX, }, - [NFQNL_MSG_VERDICT] = { .call_rcu = nfqnl_recv_verdict, - .attr_count = NFQA_MAX, - .policy = nfqa_verdict_policy }, - [NFQNL_MSG_CONFIG] = { .call = nfqnl_recv_config, - .attr_count = NFQA_CFG_MAX, - .policy = nfqa_cfg_policy }, - [NFQNL_MSG_VERDICT_BATCH]={ .call_rcu = nfqnl_recv_verdict_batch, - .attr_count = NFQA_MAX, - .policy = nfqa_verdict_batch_policy }, -}; - -static const 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 { - struct seq_net_private p; - unsigned int bucket; -}; - -static struct hlist_node *get_first(struct seq_file *seq) -{ - struct iter_state *st = seq->private; - struct net *net; - struct nfnl_queue_net *q; - - if (!st) - return NULL; - - net = seq_file_net(seq); - q = nfnl_queue_pernet(net); - for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) { - if (!hlist_empty(&q->instance_table[st->bucket])) - return q->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; - struct net *net = seq_file_net(seq); - - h = h->next; - while (!h) { - struct nfnl_queue_net *q; - - if (++st->bucket >= INSTANCE_BUCKETS) - return NULL; - - q = nfnl_queue_pernet(net); - h = q->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 *s, loff_t *pos) - __acquires(nfnl_queue_pernet(seq_file_net(s))->instances_lock) -{ - spin_lock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock); - return get_idx(s, *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) - __releases(nfnl_queue_pernet(seq_file_net(s))->instances_lock) -{ - spin_unlock(&nfnl_queue_pernet(seq_file_net(s))->instances_lock); -} - -static int seq_show(struct seq_file *s, void *v) -{ - const struct nfqnl_instance *inst = v; - - seq_printf(s, "%5u %6u %5u %1u %5u %5u %5u %8u %2d\n", - inst->queue_num, - inst->peer_portid, inst->queue_total, - inst->copy_mode, inst->copy_range, - inst->queue_dropped, inst->queue_user_dropped, - inst->id_sequence, 1); - return 0; -} - -static const 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) -{ - return seq_open_net(inode, file, &nfqnl_seq_ops, - sizeof(struct iter_state)); -} - -static const struct file_operations nfqnl_file_ops = { - .owner = THIS_MODULE, - .open = nfqnl_open, - .read = seq_read, - .llseek = seq_lseek, - .release = seq_release_net, -}; - -#endif /* PROC_FS */ - -static int __net_init nfnl_queue_net_init(struct net *net) -{ - unsigned int i; - struct nfnl_queue_net *q = nfnl_queue_pernet(net); - - for (i = 0; i < INSTANCE_BUCKETS; i++) - INIT_HLIST_HEAD(&q->instance_table[i]); - - spin_lock_init(&q->instances_lock); - -#ifdef CONFIG_PROC_FS - if (!proc_create("nfnetlink_queue", 0440, - net->nf.proc_netfilter, &nfqnl_file_ops)) - return -ENOMEM; -#endif - return 0; -} - -static void __net_exit nfnl_queue_net_exit(struct net *net) -{ -#ifdef CONFIG_PROC_FS - remove_proc_entry("nfnetlink_queue", net->nf.proc_netfilter); -#endif -} - -static struct pernet_operations nfnl_queue_net_ops = { - .init = nfnl_queue_net_init, - .exit = nfnl_queue_net_exit, - .id = &nfnl_queue_net_id, - .size = sizeof(struct nfnl_queue_net), -}; - -static int __init nfnetlink_queue_init(void) -{ - int status; - - status = register_pernet_subsys(&nfnl_queue_net_ops); - if (status < 0) { - pr_err("nf_queue: failed to register pernet ops\n"); - goto out; - } - - netlink_register_notifier(&nfqnl_rtnl_notifier); - status = nfnetlink_subsys_register(&nfqnl_subsys); - if (status < 0) { - pr_err("nf_queue: failed to create netlink socket\n"); - goto cleanup_netlink_notifier; - } - - register_netdevice_notifier(&nfqnl_dev_notifier); - nf_register_queue_handler(&nfqh); - return status; - -cleanup_netlink_notifier: - netlink_unregister_notifier(&nfqnl_rtnl_notifier); -out: - return status; -} - -static void __exit nfnetlink_queue_fini(void) -{ - nf_unregister_queue_handler(); - unregister_netdevice_notifier(&nfqnl_dev_notifier); - nfnetlink_subsys_unregister(&nfqnl_subsys); - netlink_unregister_notifier(&nfqnl_rtnl_notifier); - unregister_pernet_subsys(&nfnl_queue_net_ops); - - rcu_barrier(); /* Wait for completion of call_rcu()'s */ -} - -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); |