WSL2-Linux-Kernel/samples/sockmap/sockmap_kern.c

342 строки
8.5 KiB
C

/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <uapi/linux/bpf.h>
#include <uapi/linux/if_ether.h>
#include <uapi/linux/if_packet.h>
#include <uapi/linux/ip.h>
#include "../../tools/testing/selftests/bpf/bpf_helpers.h"
#include "../../tools/testing/selftests/bpf/bpf_endian.h"
/* Sockmap sample program connects a client and a backend together
* using cgroups.
*
* client:X <---> frontend:80 client:X <---> backend:80
*
* For simplicity we hard code values here and bind 1:1. The hard
* coded values are part of the setup in sockmap.sh script that
* is associated with this BPF program.
*
* The bpf_printk is verbose and prints information as connections
* are established and verdicts are decided.
*/
#define bpf_printk(fmt, ...) \
({ \
char ____fmt[] = fmt; \
bpf_trace_printk(____fmt, sizeof(____fmt), \
##__VA_ARGS__); \
})
struct bpf_map_def SEC("maps") sock_map = {
.type = BPF_MAP_TYPE_SOCKMAP,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 20,
};
struct bpf_map_def SEC("maps") sock_map_txmsg = {
.type = BPF_MAP_TYPE_SOCKMAP,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 20,
};
struct bpf_map_def SEC("maps") sock_map_redir = {
.type = BPF_MAP_TYPE_SOCKMAP,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 20,
};
struct bpf_map_def SEC("maps") sock_apply_bytes = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 1
};
struct bpf_map_def SEC("maps") sock_cork_bytes = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 1
};
struct bpf_map_def SEC("maps") sock_pull_bytes = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 2
};
struct bpf_map_def SEC("maps") sock_redir_flags = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 1
};
struct bpf_map_def SEC("maps") sock_skb_opts = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 1
};
SEC("sk_skb1")
int bpf_prog1(struct __sk_buff *skb)
{
return skb->len;
}
SEC("sk_skb2")
int bpf_prog2(struct __sk_buff *skb)
{
__u32 lport = skb->local_port;
__u32 rport = skb->remote_port;
int len, *f, ret, zero = 0;
__u64 flags = 0;
if (lport == 10000)
ret = 10;
else
ret = 1;
len = (__u32)skb->data_end - (__u32)skb->data;
f = bpf_map_lookup_elem(&sock_skb_opts, &zero);
if (f && *f) {
ret = 3;
flags = *f;
}
bpf_printk("sk_skb2: redirect(%iB) flags=%i\n",
len, flags);
return bpf_sk_redirect_map(skb, &sock_map, ret, flags);
}
SEC("sockops")
int bpf_sockmap(struct bpf_sock_ops *skops)
{
__u32 lport, rport;
int op, err = 0, index, key, ret;
op = (int) skops->op;
switch (op) {
case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
lport = skops->local_port;
rport = skops->remote_port;
if (lport == 10000) {
ret = 1;
err = bpf_sock_map_update(skops, &sock_map, &ret,
BPF_NOEXIST);
bpf_printk("passive(%i -> %i) map ctx update err: %d\n",
lport, bpf_ntohl(rport), err);
}
break;
case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
lport = skops->local_port;
rport = skops->remote_port;
if (bpf_ntohl(rport) == 10001) {
ret = 10;
err = bpf_sock_map_update(skops, &sock_map, &ret,
BPF_NOEXIST);
bpf_printk("active(%i -> %i) map ctx update err: %d\n",
lport, bpf_ntohl(rport), err);
}
break;
default:
break;
}
return 0;
}
SEC("sk_msg1")
int bpf_prog4(struct sk_msg_md *msg)
{
int *bytes, zero = 0, one = 1;
int *start, *end;
bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
if (bytes)
bpf_msg_apply_bytes(msg, *bytes);
bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
if (bytes)
bpf_msg_cork_bytes(msg, *bytes);
start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
if (start && end)
bpf_msg_pull_data(msg, *start, *end, 0);
return SK_PASS;
}
SEC("sk_msg2")
int bpf_prog5(struct sk_msg_md *msg)
{
int err1 = -1, err2 = -1, zero = 0, one = 1;
int *bytes, *start, *end, len1, len2;
bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
if (bytes)
err1 = bpf_msg_apply_bytes(msg, *bytes);
bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
if (bytes)
err2 = bpf_msg_cork_bytes(msg, *bytes);
len1 = (__u64)msg->data_end - (__u64)msg->data;
start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
if (start && end) {
int err;
bpf_printk("sk_msg2: pull(%i:%i)\n",
start ? *start : 0, end ? *end : 0);
err = bpf_msg_pull_data(msg, *start, *end, 0);
if (err)
bpf_printk("sk_msg2: pull_data err %i\n",
err);
len2 = (__u64)msg->data_end - (__u64)msg->data;
bpf_printk("sk_msg2: length update %i->%i\n",
len1, len2);
}
bpf_printk("sk_msg2: data length %i err1 %i err2 %i\n",
len1, err1, err2);
return SK_PASS;
}
SEC("sk_msg3")
int bpf_prog6(struct sk_msg_md *msg)
{
int *bytes, zero = 0, one = 1, key = 0;
int *start, *end, *f;
__u64 flags = 0;
bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
if (bytes)
bpf_msg_apply_bytes(msg, *bytes);
bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
if (bytes)
bpf_msg_cork_bytes(msg, *bytes);
start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
if (start && end)
bpf_msg_pull_data(msg, *start, *end, 0);
f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
if (f && *f) {
key = 2;
flags = *f;
}
return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
}
SEC("sk_msg4")
int bpf_prog7(struct sk_msg_md *msg)
{
int err1 = 0, err2 = 0, zero = 0, one = 1, key = 0;
int *f, *bytes, *start, *end, len1, len2;
__u64 flags = 0;
int err;
bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
if (bytes)
err1 = bpf_msg_apply_bytes(msg, *bytes);
bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
if (bytes)
err2 = bpf_msg_cork_bytes(msg, *bytes);
len1 = (__u64)msg->data_end - (__u64)msg->data;
start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
if (start && end) {
bpf_printk("sk_msg2: pull(%i:%i)\n",
start ? *start : 0, end ? *end : 0);
err = bpf_msg_pull_data(msg, *start, *end, 0);
if (err)
bpf_printk("sk_msg2: pull_data err %i\n",
err);
len2 = (__u64)msg->data_end - (__u64)msg->data;
bpf_printk("sk_msg2: length update %i->%i\n",
len1, len2);
}
f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
if (f && *f) {
key = 2;
flags = *f;
}
bpf_printk("sk_msg3: redirect(%iB) flags=%i err=%i\n",
len1, flags, err1 ? err1 : err2);
err = bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
bpf_printk("sk_msg3: err %i\n", err);
return err;
}
SEC("sk_msg5")
int bpf_prog8(struct sk_msg_md *msg)
{
void *data_end = (void *)(long) msg->data_end;
void *data = (void *)(long) msg->data;
int ret = 0, *bytes, zero = 0;
bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
if (bytes) {
ret = bpf_msg_apply_bytes(msg, *bytes);
if (ret)
return SK_DROP;
} else {
return SK_DROP;
}
return SK_PASS;
}
SEC("sk_msg6")
int bpf_prog9(struct sk_msg_md *msg)
{
void *data_end = (void *)(long) msg->data_end;
void *data = (void *)(long) msg->data;
int ret = 0, *bytes, zero = 0;
bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
if (bytes) {
if (((__u64)data_end - (__u64)data) >= *bytes)
return SK_PASS;
ret = bpf_msg_cork_bytes(msg, *bytes);
if (ret)
return SK_DROP;
}
return SK_PASS;
}
SEC("sk_msg7")
int bpf_prog10(struct sk_msg_md *msg)
{
int *bytes, zero = 0, one = 1;
int *start, *end;
bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
if (bytes)
bpf_msg_apply_bytes(msg, *bytes);
bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
if (bytes)
bpf_msg_cork_bytes(msg, *bytes);
start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
if (start && end)
bpf_msg_pull_data(msg, *start, *end, 0);
return SK_DROP;
}
char _license[] SEC("license") = "GPL";