OpenWrt – Rev 1
?pathlinks?
This patch allows the user to specify desired packet types (outgoing,
broadcast, unicast, etc.) on packet sockets via setsockopt.
This can reduce the load in situations where only a limited number
of packet types are necessary
Signed-off-by: Felix Fietkau <nbd@nbd.name>
--- a/include/uapi/linux/if_packet.h
+++ b/include/uapi/linux/if_packet.h
@@ -31,6 +31,8 @@ struct sockaddr_ll {
#define PACKET_KERNEL 7 /* To kernel space */
/* Unused, PACKET_FASTROUTE and PACKET_LOOPBACK are invisible to user space */
#define PACKET_FASTROUTE 6 /* Fastrouted frame */
+#define PACKET_MASK_ANY 0xffffffff /* mask for packet type bits */
+
/* Packet socket options */
@@ -54,6 +56,7 @@ struct sockaddr_ll {
#define PACKET_FANOUT 18
#define PACKET_TX_HAS_OFF 19
#define PACKET_QDISC_BYPASS 20
+#define PACKET_RECV_TYPE 21
#define PACKET_FANOUT_HASH 0
#define PACKET_FANOUT_LB 1
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1551,6 +1551,7 @@ static int packet_rcv_spkt(struct sk_buf
{
struct sock *sk;
struct sockaddr_pkt *spkt;
+ struct packet_sock *po;
/*
* When we registered the protocol we saved the socket in the data
@@ -1558,6 +1559,7 @@ static int packet_rcv_spkt(struct sk_buf
*/
sk = pt->af_packet_priv;
+ po = pkt_sk(sk);
/*
* Yank back the headers [hope the device set this
@@ -1570,7 +1572,7 @@ static int packet_rcv_spkt(struct sk_buf
* so that this procedure is noop.
*/
- if (skb->pkt_type == PACKET_LOOPBACK)
+ if (!(po->pkt_type & (1 << skb->pkt_type)))
goto out;
if (!net_eq(dev_net(dev), sock_net(sk)))
@@ -1769,12 +1771,12 @@ static int packet_rcv(struct sk_buff *sk
int skb_len = skb->len;
unsigned int snaplen, res;
- if (skb->pkt_type == PACKET_LOOPBACK)
- goto drop;
-
sk = pt->af_packet_priv;
po = pkt_sk(sk);
+ if (!(po->pkt_type & (1 << skb->pkt_type)))
+ goto drop;
+
if (!net_eq(dev_net(dev), sock_net(sk)))
goto drop;
@@ -1894,12 +1896,12 @@ static int tpacket_rcv(struct sk_buff *s
BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
- if (skb->pkt_type == PACKET_LOOPBACK)
- goto drop;
-
sk = pt->af_packet_priv;
po = pkt_sk(sk);
+ if (!(po->pkt_type & (1 << skb->pkt_type)))
+ goto drop;
+
if (!net_eq(dev_net(dev), sock_net(sk)))
goto drop;
@@ -2866,6 +2868,7 @@ static int packet_create(struct net *net
spin_lock_init(&po->bind_lock);
mutex_init(&po->pg_vec_lock);
po->prot_hook.func = packet_rcv;
+ po->pkt_type = PACKET_MASK_ANY & ~(1 << PACKET_LOOPBACK);
if (sock->type == SOCK_PACKET)
po->prot_hook.func = packet_rcv_spkt;
@@ -3489,6 +3492,16 @@ packet_setsockopt(struct socket *sock, i
po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
return 0;
}
+ case PACKET_RECV_TYPE:
+ {
+ unsigned int val;
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+ po->pkt_type = val & ~BIT(PACKET_LOOPBACK);
+ return 0;
+ }
default:
return -ENOPROTOOPT;
}
@@ -3540,6 +3553,13 @@ static int packet_getsockopt(struct sock
case PACKET_VNET_HDR:
val = po->has_vnet_hdr;
break;
+ case PACKET_RECV_TYPE:
+ if (len > sizeof(unsigned int))
+ len = sizeof(unsigned int);
+ val = po->pkt_type;
+
+ data = &val;
+ break;
case PACKET_VERSION:
val = po->tp_version;
break;
--- a/net/packet/internal.h
+++ b/net/packet/internal.h
@@ -117,6 +117,7 @@ struct packet_sock {
struct net_device __rcu *cached_dev;
int (*xmit)(struct sk_buff *skb);
struct packet_type prot_hook ____cacheline_aligned_in_smp;
+ unsigned int pkt_type;
};
static struct packet_sock *pkt_sk(struct sock *sk)