From f2e520956a1ab636698f8160194c9b8ac0989aab Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Fri, 14 Aug 2015 22:31:35 -0400 Subject: packet: add extended BPF fanout mode Add fanout mode PACKET_FANOUT_EBPF that accepts an en extended BPF program to select a socket. Update the internal eBPF program by passing to socket option SOL_PACKET/PACKET_FANOUT_DATA a file descriptor returned by bpf(). Signed-off-by: Willem de Bruijn Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- net/packet/af_packet.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'net/packet') diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 8869d07013e6..7b8e39a22387 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1472,6 +1472,7 @@ static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev, idx = fanout_demux_rollover(f, skb, 0, false, num); break; case PACKET_FANOUT_CBPF: + case PACKET_FANOUT_EBPF: idx = fanout_demux_bpf(f, skb, num); break; } @@ -1529,6 +1530,7 @@ static void fanout_init_data(struct packet_fanout *f) atomic_set(&f->rr_cur, 0); break; case PACKET_FANOUT_CBPF: + case PACKET_FANOUT_EBPF: RCU_INIT_POINTER(f->bpf_prog, NULL); break; } @@ -1571,12 +1573,39 @@ static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data, return 0; } +static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data, + unsigned int len) +{ + struct bpf_prog *new; + u32 fd; + + if (sock_flag(&po->sk, SOCK_FILTER_LOCKED)) + return -EPERM; + if (len != sizeof(fd)) + return -EINVAL; + if (copy_from_user(&fd, data, len)) + return -EFAULT; + + new = bpf_prog_get(fd); + if (IS_ERR(new)) + return PTR_ERR(new); + if (new->type != BPF_PROG_TYPE_SOCKET_FILTER) { + bpf_prog_put(new); + return -EINVAL; + } + + __fanout_set_data_bpf(po->fanout, new); + return 0; +} + static int fanout_set_data(struct packet_sock *po, char __user *data, unsigned int len) { switch (po->fanout->type) { case PACKET_FANOUT_CBPF: return fanout_set_data_cbpf(po, data, len); + case PACKET_FANOUT_EBPF: + return fanout_set_data_ebpf(po, data, len); default: return -EINVAL; }; @@ -1586,6 +1615,7 @@ static void fanout_release_data(struct packet_fanout *f) { switch (f->type) { case PACKET_FANOUT_CBPF: + case PACKET_FANOUT_EBPF: __fanout_set_data_bpf(f, NULL); }; } @@ -1608,6 +1638,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) case PACKET_FANOUT_RND: case PACKET_FANOUT_QM: case PACKET_FANOUT_CBPF: + case PACKET_FANOUT_EBPF: break; default: return -EINVAL; -- cgit v1.2.3