diff options
| -rw-r--r-- | include/uapi/linux/if_packet.h | 2 | ||||
| -rw-r--r-- | net/packet/af_packet.c | 99 | ||||
| -rw-r--r-- | net/packet/internal.h | 5 |
3 files changed, 104 insertions, 2 deletions
diff --git a/include/uapi/linux/if_packet.h b/include/uapi/linux/if_packet.h index d3d715f8c..a4bb16f 100644 --- a/include/uapi/linux/if_packet.h +++ b/include/uapi/linux/if_packet.h @@ -55,6 +55,7 @@ struct sockaddr_ll { #define PACKET_TX_HAS_OFF 19 #define PACKET_QDISC_BYPASS 20 #define PACKET_ROLLOVER_STATS 21 +#define PACKET_FANOUT_DATA 22 #define PACKET_FANOUT_HASH 0 #define PACKET_FANOUT_LB 1 @@ -62,6 +63,7 @@ struct sockaddr_ll { #define PACKET_FANOUT_ROLLOVER 3 #define PACKET_FANOUT_RND 4 #define PACKET_FANOUT_QM 5 +#define PACKET_FANOUT_CBPF 6 #define PACKET_FANOUT_FLAG_ROLLOVER 0x1000 #define PACKET_FANOUT_FLAG_DEFRAG 0x8000 diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index b5afe53..8869d07 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -92,6 +92,7 @@ #ifdef CONFIG_INET #include <net/inet_common.h> #endif +#include <linux/bpf.h> #include "internal.h" @@ -1410,6 +1411,22 @@ static unsigned int fanout_demux_qm(struct packet_fanout *f, return skb_get_queue_mapping(skb) % num; } +static unsigned int fanout_demux_bpf(struct packet_fanout *f, + struct sk_buff *skb, + unsigned int num) +{ + struct bpf_prog *prog; + unsigned int ret = 0; + + rcu_read_lock(); + prog = rcu_dereference(f->bpf_prog); + if (prog) + ret = BPF_PROG_RUN(prog, skb) % num; + rcu_read_unlock(); + + return ret; +} + static bool fanout_has_flag(struct packet_fanout *f, u16 flag) { return f->flags & (flag >> 8); @@ -1454,6 +1471,9 @@ static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev, case PACKET_FANOUT_ROLLOVER: idx = fanout_demux_rollover(f, skb, 0, false, num); break; + case PACKET_FANOUT_CBPF: + idx = fanout_demux_bpf(f, skb, num); + break; } if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER)) @@ -1502,6 +1522,74 @@ static bool match_fanout_group(struct packet_type *ptype, struct sock *sk) return false; } +static void fanout_init_data(struct packet_fanout *f) +{ + switch (f->type) { + case PACKET_FANOUT_LB: + atomic_set(&f->rr_cur, 0); + break; + case PACKET_FANOUT_CBPF: + RCU_INIT_POINTER(f->bpf_prog, NULL); + break; + } +} + +static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new) +{ + struct bpf_prog *old; + + spin_lock(&f->lock); + old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock)); + rcu_assign_pointer(f->bpf_prog, new); + spin_unlock(&f->lock); + + if (old) { + synchronize_net(); + bpf_prog_destroy(old); + } +} + +static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data, + unsigned int len) +{ + struct bpf_prog *new; + struct sock_fprog fprog; + int ret; + + if (sock_flag(&po->sk, SOCK_FILTER_LOCKED)) + return -EPERM; + if (len != sizeof(fprog)) + return -EINVAL; + if (copy_from_user(&fprog, data, len)) + return -EFAULT; + + ret = bpf_prog_create_from_user(&new, &fprog, NULL); + if (ret) + return ret; + + __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); + default: + return -EINVAL; + }; +} + +static void fanout_release_data(struct packet_fanout *f) +{ + switch (f->type) { + case PACKET_FANOUT_CBPF: + __fanout_set_data_bpf(f, NULL); + }; +} + static int fanout_add(struct sock *sk, u16 id, u16 type_flags) { struct packet_sock *po = pkt_sk(sk); @@ -1519,6 +1607,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) case PACKET_FANOUT_CPU: case PACKET_FANOUT_RND: case PACKET_FANOUT_QM: + case PACKET_FANOUT_CBPF: break; default: return -EINVAL; @@ -1561,10 +1650,10 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) match->id = id; match->type = type; match->flags = flags; - atomic_set(&match->rr_cur, 0); INIT_LIST_HEAD(&match->list); spin_lock_init(&match->lock); atomic_set(&match->sk_ref, 0); + fanout_init_data(match); match->prot_hook.type = po->prot_hook.type; match->prot_hook.dev = po->prot_hook.dev; match->prot_hook.func = packet_rcv_fanout; @@ -1610,6 +1699,7 @@ static void fanout_release(struct sock *sk) if (atomic_dec_and_test(&f->sk_ref)) { list_del(&f->list); dev_remove_pack(&f->prot_hook); + fanout_release_data(f); kfree(f); } mutex_unlock(&fanout_mutex); @@ -3529,6 +3619,13 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv return fanout_add(sk, val & 0xffff, val >> 16); } + case PACKET_FANOUT_DATA: + { + if (!po->fanout) + return -EINVAL; + + return fanout_set_data(po, optval, optlen); + } case PACKET_TX_HAS_OFF: { unsigned int val; diff --git a/net/packet/internal.h b/net/packet/internal.h index e20b3e8..9ee4631 100644 --- a/net/packet/internal.h +++ b/net/packet/internal.h @@ -79,7 +79,10 @@ struct packet_fanout { u16 id; u8 type; u8 flags; - atomic_t rr_cur; + union { + atomic_t rr_cur; + struct bpf_prog __rcu *bpf_prog; + }; struct list_head list; struct sock *arr[PACKET_FANOUT_MAX]; spinlock_t lock; |
