bpf: add new prog type for cgroup socket filtering

This program type is similar to BPF_PROG_TYPE_SOCKET_FILTER, except that
it does not allow BPF_LD_[ABS|IND] instructions and hooks up the
bpf_skb_load_bytes() helper.

Programs of this type will be attached to cgroups for network filtering
and accounting.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Mack 2016-11-23 16:52:25 +01:00 committed by David S. Miller
parent 619228d86b
commit 0e33661de4
2 changed files with 32 additions and 0 deletions

View File

@ -98,8 +98,17 @@ enum bpf_prog_type {
BPF_PROG_TYPE_TRACEPOINT,
BPF_PROG_TYPE_XDP,
BPF_PROG_TYPE_PERF_EVENT,
BPF_PROG_TYPE_CGROUP_SKB,
};
enum bpf_attach_type {
BPF_CGROUP_INET_INGRESS,
BPF_CGROUP_INET_EGRESS,
__MAX_BPF_ATTACH_TYPE
};
#define MAX_BPF_ATTACH_TYPE __MAX_BPF_ATTACH_TYPE
#define BPF_PSEUDO_MAP_FD 1
/* flags for BPF_MAP_UPDATE_ELEM command */

View File

@ -2630,6 +2630,17 @@ xdp_func_proto(enum bpf_func_id func_id)
}
}
static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id)
{
switch (func_id) {
case BPF_FUNC_skb_load_bytes:
return &bpf_skb_load_bytes_proto;
default:
return sk_filter_func_proto(func_id);
}
}
static bool __is_valid_access(int off, int size, enum bpf_access_type type)
{
if (off < 0 || off >= sizeof(struct __sk_buff))
@ -2992,6 +3003,12 @@ static const struct bpf_verifier_ops xdp_ops = {
.convert_ctx_access = xdp_convert_ctx_access,
};
static const struct bpf_verifier_ops cg_skb_ops = {
.get_func_proto = cg_skb_func_proto,
.is_valid_access = sk_filter_is_valid_access,
.convert_ctx_access = sk_filter_convert_ctx_access,
};
static struct bpf_prog_type_list sk_filter_type __read_mostly = {
.ops = &sk_filter_ops,
.type = BPF_PROG_TYPE_SOCKET_FILTER,
@ -3012,12 +3029,18 @@ static struct bpf_prog_type_list xdp_type __read_mostly = {
.type = BPF_PROG_TYPE_XDP,
};
static struct bpf_prog_type_list cg_skb_type __read_mostly = {
.ops = &cg_skb_ops,
.type = BPF_PROG_TYPE_CGROUP_SKB,
};
static int __init register_sk_filter_ops(void)
{
bpf_register_prog_type(&sk_filter_type);
bpf_register_prog_type(&sched_cls_type);
bpf_register_prog_type(&sched_act_type);
bpf_register_prog_type(&xdp_type);
bpf_register_prog_type(&cg_skb_type);
return 0;
}