add an optimization for dealing with raw sockets, which allows applications to filter...
[openwrt/openwrt.git] / target / linux / generic-2.6 / patches-2.6.28 / 240-packet_socket_type.patch
1 This patch allows the user to specify desired packet types (outgoing,
2 broadcast, unicast, etc.) on packet sockets via setsockopt.
3 This can reduce the load in situations where only a limited number
4 of packet types are necessary
5
6 Signed-off-by: Felix Fietkau <nbd@openwrt.org>
7
8 --- a/include/linux/if_packet.h
9 +++ b/include/linux/if_packet.h
10 @@ -31,6 +31,8 @@ struct sockaddr_ll
11 /* These ones are invisible by user level */
12 #define PACKET_LOOPBACK 5 /* MC/BRD frame looped back */
13 #define PACKET_FASTROUTE 6 /* Fastrouted frame */
14 +#define PACKET_ANY 0xffffffff
15 +
16
17 /* Packet socket options */
18
19 @@ -46,6 +48,7 @@ struct sockaddr_ll
20 #define PACKET_VERSION 10
21 #define PACKET_HDRLEN 11
22 #define PACKET_RESERVE 12
23 +#define PACKET_RECV_TYPE 13
24
25 struct tpacket_stats
26 {
27 --- a/net/packet/af_packet.c
28 +++ b/net/packet/af_packet.c
29 @@ -192,6 +192,7 @@ struct packet_sock {
30 unsigned int tp_hdrlen;
31 unsigned int tp_reserve;
32 #endif
33 + int pkt_type;
34 };
35
36 struct packet_skb_cb {
37 @@ -282,6 +283,7 @@ static int packet_rcv_spkt(struct sk_buf
38 {
39 struct sock *sk;
40 struct sockaddr_pkt *spkt;
41 + struct packet_sock *po;
42
43 /*
44 * When we registered the protocol we saved the socket in the data
45 @@ -289,6 +291,7 @@ static int packet_rcv_spkt(struct sk_buf
46 */
47
48 sk = pt->af_packet_priv;
49 + po = pkt_sk(sk);
50
51 /*
52 * Yank back the headers [hope the device set this
53 @@ -301,7 +304,7 @@ static int packet_rcv_spkt(struct sk_buf
54 * so that this procedure is noop.
55 */
56
57 - if (skb->pkt_type == PACKET_LOOPBACK)
58 + if (!(po->pkt_type & (1 << skb->pkt_type)))
59 goto out;
60
61 if (dev_net(dev) != sock_net(sk))
62 @@ -486,12 +489,12 @@ static int packet_rcv(struct sk_buff *sk
63 int skb_len = skb->len;
64 unsigned int snaplen, res;
65
66 - if (skb->pkt_type == PACKET_LOOPBACK)
67 - goto drop;
68 -
69 sk = pt->af_packet_priv;
70 po = pkt_sk(sk);
71
72 + if (!(po->pkt_type & (1 << skb->pkt_type)))
73 + goto drop;
74 +
75 if (dev_net(dev) != sock_net(sk))
76 goto drop;
77
78 @@ -608,12 +611,12 @@ static int tpacket_rcv(struct sk_buff *s
79 struct timeval tv;
80 struct timespec ts;
81
82 - if (skb->pkt_type == PACKET_LOOPBACK)
83 - goto drop;
84 -
85 sk = pt->af_packet_priv;
86 po = pkt_sk(sk);
87
88 + if (!(po->pkt_type & (1 << skb->pkt_type)))
89 + goto drop;
90 +
91 if (dev_net(dev) != sock_net(sk))
92 goto drop;
93
94 @@ -1072,6 +1075,7 @@ static int packet_create(struct net *net
95 spin_lock_init(&po->bind_lock);
96 mutex_init(&po->pg_vec_lock);
97 po->prot_hook.func = packet_rcv;
98 + po->pkt_type = PACKET_ANY & ~PACKET_LOOPBACK;
99
100 if (sock->type == SOCK_PACKET)
101 po->prot_hook.func = packet_rcv_spkt;
102 @@ -1411,6 +1415,16 @@ packet_setsockopt(struct socket *sock, i
103 ret = packet_mc_drop(sk, &mreq);
104 return ret;
105 }
106 + case PACKET_RECV_TYPE:
107 + {
108 + int val;
109 + if (optlen != sizeof(val))
110 + return -EINVAL;
111 + if (copy_from_user(&val, optval, sizeof(val)))
112 + return -EFAULT;
113 + po->pkt_type = val & ~PACKET_LOOPBACK;
114 + return 0;
115 + }
116
117 #ifdef CONFIG_PACKET_MMAP
118 case PACKET_RX_RING:
119 @@ -1542,6 +1556,13 @@ static int packet_getsockopt(struct sock
120
121 data = &val;
122 break;
123 + case PACKET_RECV_TYPE:
124 + if (len > sizeof(int))
125 + len = sizeof(int);
126 + val = po->pkt_type;
127 +
128 + data = &val;
129 + break;
130 #ifdef CONFIG_PACKET_MMAP
131 case PACKET_VERSION:
132 if (len > sizeof(int))