1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
// SPDX-License-Identifier: GPL-2.0-only
/* Unstable NAT Helpers for XDP and TC-BPF hook
*
* These are called from the XDP and SCHED_CLS BPF programs. Note that it is
* allowed to break compatibility for these functions since the interface they
* are exposed through to BPF programs is explicitly unstable.
*/
#include <linux/bpf.h>
#include <linux/btf_ids.h>
#include <net/netfilter/nf_conntrack_bpf.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_nat.h>
__bpf_kfunc_start_defs();
/* bpf_ct_set_nat_info - Set source or destination nat address
*
* Set source or destination nat address of the newly allocated
* nf_conn before insertion. This must be invoked for referenced
* PTR_TO_BTF_ID to nf_conn___init.
*
* Parameters:
* @nfct - Pointer to referenced nf_conn object, obtained using
* bpf_xdp_ct_alloc or bpf_skb_ct_alloc.
* @addr - Nat source/destination address
* @port - Nat source/destination port. Non-positive values are
* interpreted as select a random port.
* @manip - NF_NAT_MANIP_SRC or NF_NAT_MANIP_DST
*/
__bpf_kfunc int bpf_ct_set_nat_info(struct nf_conn___init *nfct,
union nf_inet_addr *addr, int port,
enum nf_nat_manip_type manip)
{
struct nf_conn *ct = (struct nf_conn *)nfct;
u16 proto = nf_ct_l3num(ct);
struct nf_nat_range2 range;
if (proto != NFPROTO_IPV4 && proto != NFPROTO_IPV6)
return -EINVAL;
memset(&range, 0, sizeof(struct nf_nat_range2));
range.flags = NF_NAT_RANGE_MAP_IPS;
range.min_addr = *addr;
range.max_addr = range.min_addr;
if (port > 0) {
range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
range.min_proto.all = cpu_to_be16(port);
range.max_proto.all = range.min_proto.all;
}
return nf_nat_setup_info(ct, &range, manip) == NF_DROP ? -ENOMEM : 0;
}
__bpf_kfunc_end_defs();
BTF_KFUNCS_START(nf_nat_kfunc_set)
BTF_ID_FLAGS(func, bpf_ct_set_nat_info, KF_TRUSTED_ARGS)
BTF_KFUNCS_END(nf_nat_kfunc_set)
static const struct btf_kfunc_id_set nf_bpf_nat_kfunc_set = {
.owner = THIS_MODULE,
.set = &nf_nat_kfunc_set,
};
int register_nf_nat_bpf(void)
{
int ret;
ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP,
&nf_bpf_nat_kfunc_set);
if (ret)
return ret;
return register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS,
&nf_bpf_nat_kfunc_set);
}
|
