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Diffstat (limited to 'net/packet/af_packet.c')
-rw-r--r--net/packet/af_packet.c438
1 files changed, 374 insertions, 64 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index c0c3cda19712..c698cec0a445 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -187,9 +187,11 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
static void packet_flush_mclist(struct sock *sk);
+struct packet_fanout;
struct packet_sock {
/* struct sock has to be the first member of packet_sock */
struct sock sk;
+ struct packet_fanout *fanout;
struct tpacket_stats stats;
struct packet_ring_buffer rx_ring;
struct packet_ring_buffer tx_ring;
@@ -212,6 +214,24 @@ struct packet_sock {
struct packet_type prot_hook ____cacheline_aligned_in_smp;
};
+#define PACKET_FANOUT_MAX 256
+
+struct packet_fanout {
+#ifdef CONFIG_NET_NS
+ struct net *net;
+#endif
+ unsigned int num_members;
+ u16 id;
+ u8 type;
+ u8 defrag;
+ atomic_t rr_cur;
+ struct list_head list;
+ struct sock *arr[PACKET_FANOUT_MAX];
+ spinlock_t lock;
+ atomic_t sk_ref;
+ struct packet_type prot_hook ____cacheline_aligned_in_smp;
+};
+
struct packet_skb_cb {
unsigned int origlen;
union {
@@ -222,6 +242,64 @@ struct packet_skb_cb {
#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
+static inline struct packet_sock *pkt_sk(struct sock *sk)
+{
+ return (struct packet_sock *)sk;
+}
+
+static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
+static void __fanout_link(struct sock *sk, struct packet_sock *po);
+
+/* register_prot_hook must be invoked with the po->bind_lock held,
+ * or from a context in which asynchronous accesses to the packet
+ * socket is not possible (packet_create()).
+ */
+static void register_prot_hook(struct sock *sk)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ if (!po->running) {
+ if (po->fanout)
+ __fanout_link(sk, po);
+ else
+ dev_add_pack(&po->prot_hook);
+ sock_hold(sk);
+ po->running = 1;
+ }
+}
+
+/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
+ * held. If the sync parameter is true, we will temporarily drop
+ * the po->bind_lock and do a synchronize_net to make sure no
+ * asynchronous packet processing paths still refer to the elements
+ * of po->prot_hook. If the sync parameter is false, it is the
+ * callers responsibility to take care of this.
+ */
+static void __unregister_prot_hook(struct sock *sk, bool sync)
+{
+ struct packet_sock *po = pkt_sk(sk);
+
+ po->running = 0;
+ if (po->fanout)
+ __fanout_unlink(sk, po);
+ else
+ __dev_remove_pack(&po->prot_hook);
+ __sock_put(sk);
+
+ if (sync) {
+ spin_unlock(&po->bind_lock);
+ synchronize_net();
+ spin_lock(&po->bind_lock);
+ }
+}
+
+static void unregister_prot_hook(struct sock *sk, bool sync)
+{
+ struct packet_sock *po = pkt_sk(sk);
+
+ if (po->running)
+ __unregister_prot_hook(sk, sync);
+}
+
static inline __pure struct page *pgv_to_page(void *addr)
{
if (is_vmalloc_addr(addr))
@@ -324,11 +402,6 @@ static inline void packet_increment_head(struct packet_ring_buffer *buff)
buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
}
-static inline struct packet_sock *pkt_sk(struct sock *sk)
-{
- return (struct packet_sock *)sk;
-}
-
static void packet_sock_destruct(struct sock *sk)
{
skb_queue_purge(&sk->sk_error_queue);
@@ -344,6 +417,240 @@ static void packet_sock_destruct(struct sock *sk)
sk_refcnt_debug_dec(sk);
}
+static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
+{
+ int x = atomic_read(&f->rr_cur) + 1;
+
+ if (x >= num)
+ x = 0;
+
+ return x;
+}
+
+static struct sock *fanout_demux_hash(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
+{
+ u32 idx, hash = skb->rxhash;
+
+ idx = ((u64)hash * num) >> 32;
+
+ return f->arr[idx];
+}
+
+static struct sock *fanout_demux_lb(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
+{
+ int cur, old;
+
+ cur = atomic_read(&f->rr_cur);
+ while ((old = atomic_cmpxchg(&f->rr_cur, cur,
+ fanout_rr_next(f, num))) != cur)
+ cur = old;
+ return f->arr[cur];
+}
+
+static struct sock *fanout_demux_cpu(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
+{
+ unsigned int cpu = smp_processor_id();
+
+ return f->arr[cpu % num];
+}
+
+static struct sk_buff *fanout_check_defrag(struct sk_buff *skb)
+{
+#ifdef CONFIG_INET
+ const struct iphdr *iph;
+ u32 len;
+
+ if (skb->protocol != htons(ETH_P_IP))
+ return skb;
+
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ return skb;
+
+ iph = ip_hdr(skb);
+ if (iph->ihl < 5 || iph->version != 4)
+ return skb;
+ if (!pskb_may_pull(skb, iph->ihl*4))
+ return skb;
+ iph = ip_hdr(skb);
+ len = ntohs(iph->tot_len);
+ if (skb->len < len || len < (iph->ihl * 4))
+ return skb;
+
+ if (ip_is_fragment(ip_hdr(skb))) {
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (skb) {
+ if (pskb_trim_rcsum(skb, len))
+ return skb;
+ memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
+ if (ip_defrag(skb, IP_DEFRAG_AF_PACKET))
+ return NULL;
+ skb->rxhash = 0;
+ }
+ }
+#endif
+ return skb;
+}
+
+static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct packet_fanout *f = pt->af_packet_priv;
+ unsigned int num = f->num_members;
+ struct packet_sock *po;
+ struct sock *sk;
+
+ if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
+ !num) {
+ kfree_skb(skb);
+ return 0;
+ }
+
+ switch (f->type) {
+ case PACKET_FANOUT_HASH:
+ default:
+ if (f->defrag) {
+ skb = fanout_check_defrag(skb);
+ if (!skb)
+ return 0;
+ }
+ skb_get_rxhash(skb);
+ sk = fanout_demux_hash(f, skb, num);
+ break;
+ case PACKET_FANOUT_LB:
+ sk = fanout_demux_lb(f, skb, num);
+ break;
+ case PACKET_FANOUT_CPU:
+ sk = fanout_demux_cpu(f, skb, num);
+ break;
+ }
+
+ po = pkt_sk(sk);
+
+ return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
+}
+
+static DEFINE_MUTEX(fanout_mutex);
+static LIST_HEAD(fanout_list);
+
+static void __fanout_link(struct sock *sk, struct packet_sock *po)
+{
+ struct packet_fanout *f = po->fanout;
+
+ spin_lock(&f->lock);
+ f->arr[f->num_members] = sk;
+ smp_wmb();
+ f->num_members++;
+ spin_unlock(&f->lock);
+}
+
+static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
+{
+ struct packet_fanout *f = po->fanout;
+ int i;
+
+ spin_lock(&f->lock);
+ for (i = 0; i < f->num_members; i++) {
+ if (f->arr[i] == sk)
+ break;
+ }
+ BUG_ON(i >= f->num_members);
+ f->arr[i] = f->arr[f->num_members - 1];
+ f->num_members--;
+ spin_unlock(&f->lock);
+}
+
+static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ struct packet_fanout *f, *match;
+ u8 type = type_flags & 0xff;
+ u8 defrag = (type_flags & PACKET_FANOUT_FLAG_DEFRAG) ? 1 : 0;
+ int err;
+
+ switch (type) {
+ case PACKET_FANOUT_HASH:
+ case PACKET_FANOUT_LB:
+ case PACKET_FANOUT_CPU:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (!po->running)
+ return -EINVAL;
+
+ if (po->fanout)
+ return -EALREADY;
+
+ mutex_lock(&fanout_mutex);
+ match = NULL;
+ list_for_each_entry(f, &fanout_list, list) {
+ if (f->id == id &&
+ read_pnet(&f->net) == sock_net(sk)) {
+ match = f;
+ break;
+ }
+ }
+ err = -EINVAL;
+ if (match && match->defrag != defrag)
+ goto out;
+ if (!match) {
+ err = -ENOMEM;
+ match = kzalloc(sizeof(*match), GFP_KERNEL);
+ if (!match)
+ goto out;
+ write_pnet(&match->net, sock_net(sk));
+ match->id = id;
+ match->type = type;
+ match->defrag = defrag;
+ atomic_set(&match->rr_cur, 0);
+ INIT_LIST_HEAD(&match->list);
+ spin_lock_init(&match->lock);
+ atomic_set(&match->sk_ref, 0);
+ match->prot_hook.type = po->prot_hook.type;
+ match->prot_hook.dev = po->prot_hook.dev;
+ match->prot_hook.func = packet_rcv_fanout;
+ match->prot_hook.af_packet_priv = match;
+ dev_add_pack(&match->prot_hook);
+ list_add(&match->list, &fanout_list);
+ }
+ err = -EINVAL;
+ if (match->type == type &&
+ match->prot_hook.type == po->prot_hook.type &&
+ match->prot_hook.dev == po->prot_hook.dev) {
+ err = -ENOSPC;
+ if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
+ __dev_remove_pack(&po->prot_hook);
+ po->fanout = match;
+ atomic_inc(&match->sk_ref);
+ __fanout_link(sk, po);
+ err = 0;
+ }
+ }
+out:
+ mutex_unlock(&fanout_mutex);
+ return err;
+}
+
+static void fanout_release(struct sock *sk)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ struct packet_fanout *f;
+
+ f = po->fanout;
+ if (!f)
+ return;
+
+ po->fanout = NULL;
+
+ mutex_lock(&fanout_mutex);
+ if (atomic_dec_and_test(&f->sk_ref)) {
+ list_del(&f->list);
+ dev_remove_pack(&f->prot_hook);
+ kfree(f);
+ }
+ mutex_unlock(&fanout_mutex);
+}
static const struct proto_ops packet_ops;
@@ -822,7 +1129,6 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
else
sll->sll_ifindex = dev->ifindex;
- __packet_set_status(po, h.raw, status);
smp_mb();
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
{
@@ -831,8 +1137,10 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
end = (u8 *)PAGE_ALIGN((unsigned long)h.raw + macoff + snaplen);
for (start = h.raw; start < end; start += PAGE_SIZE)
flush_dcache_page(pgv_to_page(start));
+ smp_wmb();
}
#endif
+ __packet_set_status(po, h.raw, status);
sk->sk_data_ready(sk, 0);
@@ -975,7 +1283,8 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
struct sk_buff *skb;
struct net_device *dev;
__be16 proto;
- int ifindex, err, reserve = 0;
+ bool need_rls_dev = false;
+ int err, reserve = 0;
void *ph;
struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
int tp_len, size_max;
@@ -987,7 +1296,7 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
err = -EBUSY;
if (saddr == NULL) {
- ifindex = po->ifindex;
+ dev = po->prot_hook.dev;
proto = po->num;
addr = NULL;
} else {
@@ -998,12 +1307,12 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
+ offsetof(struct sockaddr_ll,
sll_addr)))
goto out;
- ifindex = saddr->sll_ifindex;
proto = saddr->sll_protocol;
addr = saddr->sll_addr;
+ dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
+ need_rls_dev = true;
}
- dev = dev_get_by_index(sock_net(&po->sk), ifindex);
err = -ENXIO;
if (unlikely(dev == NULL))
goto out;
@@ -1089,7 +1398,8 @@ out_status:
__packet_set_status(po, ph, status);
kfree_skb(skb);
out_put:
- dev_put(dev);
+ if (need_rls_dev)
+ dev_put(dev);
out:
mutex_unlock(&po->pg_vec_lock);
return err;
@@ -1127,8 +1437,9 @@ static int packet_snd(struct socket *sock,
struct sk_buff *skb;
struct net_device *dev;
__be16 proto;
+ bool need_rls_dev = false;
unsigned char *addr;
- int ifindex, err, reserve = 0;
+ int err, reserve = 0;
struct virtio_net_hdr vnet_hdr = { 0 };
int offset = 0;
int vnet_hdr_len;
@@ -1140,7 +1451,7 @@ static int packet_snd(struct socket *sock,
*/
if (saddr == NULL) {
- ifindex = po->ifindex;
+ dev = po->prot_hook.dev;
proto = po->num;
addr = NULL;
} else {
@@ -1149,13 +1460,12 @@ static int packet_snd(struct socket *sock,
goto out;
if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
goto out;
- ifindex = saddr->sll_ifindex;
proto = saddr->sll_protocol;
addr = saddr->sll_addr;
+ dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
+ need_rls_dev = true;
}
-
- dev = dev_get_by_index(sock_net(sk), ifindex);
err = -ENXIO;
if (dev == NULL)
goto out_unlock;
@@ -1286,14 +1596,15 @@ static int packet_snd(struct socket *sock,
if (err > 0 && (err = net_xmit_errno(err)) != 0)
goto out_unlock;
- dev_put(dev);
+ if (need_rls_dev)
+ dev_put(dev);
return len;
out_free:
kfree_skb(skb);
out_unlock:
- if (dev)
+ if (dev && need_rls_dev)
dev_put(dev);
out:
return err;
@@ -1334,14 +1645,10 @@ static int packet_release(struct socket *sock)
spin_unlock_bh(&net->packet.sklist_lock);
spin_lock(&po->bind_lock);
- if (po->running) {
- /*
- * Remove from protocol table
- */
- po->running = 0;
- po->num = 0;
- __dev_remove_pack(&po->prot_hook);
- __sock_put(sk);
+ unregister_prot_hook(sk, false);
+ if (po->prot_hook.dev) {
+ dev_put(po->prot_hook.dev);
+ po->prot_hook.dev = NULL;
}
spin_unlock(&po->bind_lock);
@@ -1355,6 +1662,8 @@ static int packet_release(struct socket *sock)
if (po->tx_ring.pg_vec)
packet_set_ring(sk, &req, 1, 1);
+ fanout_release(sk);
+
synchronize_net();
/*
* Now the socket is dead. No more input will appear.
@@ -1378,24 +1687,18 @@ static int packet_release(struct socket *sock)
static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
{
struct packet_sock *po = pkt_sk(sk);
- /*
- * Detach an existing hook if present.
- */
+
+ if (po->fanout)
+ return -EINVAL;
lock_sock(sk);
spin_lock(&po->bind_lock);
- if (po->running) {
- __sock_put(sk);
- po->running = 0;
- po->num = 0;
- spin_unlock(&po->bind_lock);
- dev_remove_pack(&po->prot_hook);
- spin_lock(&po->bind_lock);
- }
-
+ unregister_prot_hook(sk, true);
po->num = protocol;
po->prot_hook.type = protocol;
+ if (po->prot_hook.dev)
+ dev_put(po->prot_hook.dev);
po->prot_hook.dev = dev;
po->ifindex = dev ? dev->ifindex : 0;
@@ -1404,9 +1707,7 @@ static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protoc
goto out_unlock;
if (!dev || (dev->flags & IFF_UP)) {
- dev_add_pack(&po->prot_hook);
- sock_hold(sk);
- po->running = 1;
+ register_prot_hook(sk);
} else {
sk->sk_err = ENETDOWN;
if (!sock_flag(sk, SOCK_DEAD))
@@ -1440,10 +1741,8 @@ static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
strlcpy(name, uaddr->sa_data, sizeof(name));
dev = dev_get_by_name(sock_net(sk), name);
- if (dev) {
+ if (dev)
err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
- dev_put(dev);
- }
return err;
}
@@ -1471,8 +1770,6 @@ static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len
goto out;
}
err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
- if (dev)
- dev_put(dev);
out:
return err;
@@ -1537,9 +1834,7 @@ static int packet_create(struct net *net, struct socket *sock, int protocol,
if (proto) {
po->prot_hook.type = proto;
- dev_add_pack(&po->prot_hook);
- sock_hold(sk);
- po->running = 1;
+ register_prot_hook(sk);
}
spin_lock_bh(&net->packet.sklist_lock);
@@ -1681,6 +1976,8 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
vnet_hdr.csum_start = skb_checksum_start_offset(skb);
vnet_hdr.csum_offset = skb->csum_offset;
+ } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
+ vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
} /* else everything is zero */
err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
@@ -2102,6 +2399,17 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv
po->tp_tstamp = val;
return 0;
}
+ case PACKET_FANOUT:
+ {
+ int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ return fanout_add(sk, val & 0xffff, val >> 16);
+ }
default:
return -ENOPROTOOPT;
}
@@ -2200,6 +2508,15 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
val = po->tp_tstamp;
data = &val;
break;
+ case PACKET_FANOUT:
+ if (len > sizeof(int))
+ len = sizeof(int);
+ val = (po->fanout ?
+ ((u32)po->fanout->id |
+ ((u32)po->fanout->type << 16)) :
+ 0);
+ data = &val;
+ break;
default:
return -ENOPROTOOPT;
}
@@ -2233,15 +2550,15 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void
if (dev->ifindex == po->ifindex) {
spin_lock(&po->bind_lock);
if (po->running) {
- __dev_remove_pack(&po->prot_hook);
- __sock_put(sk);
- po->running = 0;
+ __unregister_prot_hook(sk, false);
sk->sk_err = ENETDOWN;
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_error_report(sk);
}
if (msg == NETDEV_UNREGISTER) {
po->ifindex = -1;
+ if (po->prot_hook.dev)
+ dev_put(po->prot_hook.dev);
po->prot_hook.dev = NULL;
}
spin_unlock(&po->bind_lock);
@@ -2250,11 +2567,8 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void
case NETDEV_UP:
if (dev->ifindex == po->ifindex) {
spin_lock(&po->bind_lock);
- if (po->num && !po->running) {
- dev_add_pack(&po->prot_hook);
- sock_hold(sk);
- po->running = 1;
- }
+ if (po->num)
+ register_prot_hook(sk);
spin_unlock(&po->bind_lock);
}
break;
@@ -2521,10 +2835,8 @@ static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
was_running = po->running;
num = po->num;
if (was_running) {
- __dev_remove_pack(&po->prot_hook);
po->num = 0;
- po->running = 0;
- __sock_put(sk);
+ __unregister_prot_hook(sk, false);
}
spin_unlock(&po->bind_lock);
@@ -2555,11 +2867,9 @@ static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
mutex_unlock(&po->pg_vec_lock);
spin_lock(&po->bind_lock);
- if (was_running && !po->running) {
- sock_hold(sk);
- po->running = 1;
+ if (was_running) {
po->num = num;
- dev_add_pack(&po->prot_hook);
+ register_prot_hook(sk);
}
spin_unlock(&po->bind_lock);