OpenWrt – Rev 1

Subversion Repositories:
Rev:
From: Felix Fietkau <nbd@nbd.name>
Subject: net: add an optimization for dealing with raw sockets

lede-commit: 4898039703d7315f0f3431c860123338ec3be0f6
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 include/uapi/linux/if_packet.h |  3 +++
 net/packet/af_packet.c         | 34 +++++++++++++++++++++++++++-------
 net/packet/internal.h          |  1 +
 3 files changed, 31 insertions(+), 7 deletions(-)

--- a/include/uapi/linux/if_packet.h
+++ b/include/uapi/linux/if_packet.h
@@ -32,6 +32,8 @@ 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 */
 
@@ -57,6 +59,7 @@ struct sockaddr_ll {
 #define PACKET_QDISC_BYPASS            20
 #define PACKET_ROLLOVER_STATS          21
 #define PACKET_FANOUT_DATA             22
+#define PACKET_RECV_TYPE               23
 
 #define PACKET_FANOUT_HASH             0
 #define PACKET_FANOUT_LB               1
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1789,6 +1789,7 @@ 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
@@ -1796,6 +1797,7 @@ 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
@@ -1808,7 +1810,7 @@ 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)))
@@ -2036,12 +2038,12 @@ static int packet_rcv(struct sk_buff *sk
        unsigned int snaplen, res;
        bool is_drop_n_account = false;
 
-       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;
 
@@ -2167,12 +2169,12 @@ 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;
 
@@ -3233,6 +3235,7 @@ static int packet_create(struct net *net
        mutex_init(&po->pg_vec_lock);
        po->rollover = NULL;
        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;
@@ -3844,6 +3847,16 @@ 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;
        }
@@ -3896,6 +3909,13 @@ 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
@@ -131,6 +131,7 @@ 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)