| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame] | 1 | /* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io |
| 2 | * |
| 3 | * This program is free software; you can redistribute it and/or |
| 4 | * modify it under the terms of version 2 of the GNU General Public |
| 5 | * License as published by the Free Software Foundation. |
| 6 | * |
| 7 | * This program is distributed in the hope that it will be useful, but |
| 8 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 9 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 10 | * General Public License for more details. |
| 11 | */ |
| 12 | #include <uapi/linux/bpf.h> |
| 13 | #include <uapi/linux/if_ether.h> |
| 14 | #include <uapi/linux/if_packet.h> |
| 15 | #include <uapi/linux/ip.h> |
| 16 | #include "../../tools/testing/selftests/bpf/bpf_helpers.h" |
| 17 | #include "../../tools/testing/selftests/bpf/bpf_endian.h" |
| 18 | |
| 19 | /* Sockmap sample program connects a client and a backend together |
| 20 | * using cgroups. |
| 21 | * |
| 22 | * client:X <---> frontend:80 client:X <---> backend:80 |
| 23 | * |
| 24 | * For simplicity we hard code values here and bind 1:1. The hard |
| 25 | * coded values are part of the setup in sockmap.sh script that |
| 26 | * is associated with this BPF program. |
| 27 | * |
| 28 | * The bpf_printk is verbose and prints information as connections |
| 29 | * are established and verdicts are decided. |
| 30 | */ |
| 31 | |
| 32 | #define bpf_printk(fmt, ...) \ |
| 33 | ({ \ |
| 34 | char ____fmt[] = fmt; \ |
| 35 | bpf_trace_printk(____fmt, sizeof(____fmt), \ |
| 36 | ##__VA_ARGS__); \ |
| 37 | }) |
| 38 | |
| 39 | struct bpf_map_def SEC("maps") sock_map = { |
| 40 | .type = BPF_MAP_TYPE_SOCKMAP, |
| 41 | .key_size = sizeof(int), |
| 42 | .value_size = sizeof(int), |
| 43 | .max_entries = 20, |
| 44 | }; |
| 45 | |
| 46 | SEC("sk_skb1") |
| 47 | int bpf_prog1(struct __sk_buff *skb) |
| 48 | { |
| 49 | return skb->len; |
| 50 | } |
| 51 | |
| 52 | SEC("sk_skb2") |
| 53 | int bpf_prog2(struct __sk_buff *skb) |
| 54 | { |
| 55 | __u32 lport = skb->local_port; |
| 56 | __u32 rport = skb->remote_port; |
| 57 | int ret = 0; |
| 58 | |
| 59 | if (lport == 10000) |
| 60 | ret = 10; |
| 61 | else |
| 62 | ret = 1; |
| 63 | |
| 64 | bpf_printk("sockmap: %d -> %d @ %d\n", lport, bpf_ntohl(rport), ret); |
| 65 | return bpf_sk_redirect_map(skb, &sock_map, ret, 0); |
| 66 | } |
| 67 | |
| 68 | SEC("sockops") |
| 69 | int bpf_sockmap(struct bpf_sock_ops *skops) |
| 70 | { |
| 71 | __u32 lport, rport; |
| 72 | int op, err = 0, index, key, ret; |
| 73 | |
| 74 | |
| 75 | op = (int) skops->op; |
| 76 | |
| 77 | switch (op) { |
| 78 | case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB: |
| 79 | lport = skops->local_port; |
| 80 | rport = skops->remote_port; |
| 81 | |
| 82 | if (lport == 10000) { |
| 83 | ret = 1; |
| 84 | err = bpf_sock_map_update(skops, &sock_map, &ret, |
| 85 | BPF_NOEXIST); |
| 86 | bpf_printk("passive(%i -> %i) map ctx update err: %d\n", |
| 87 | lport, bpf_ntohl(rport), err); |
| 88 | } |
| 89 | break; |
| 90 | case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: |
| 91 | lport = skops->local_port; |
| 92 | rport = skops->remote_port; |
| 93 | |
| 94 | if (bpf_ntohl(rport) == 10001) { |
| 95 | ret = 10; |
| 96 | err = bpf_sock_map_update(skops, &sock_map, &ret, |
| 97 | BPF_NOEXIST); |
| 98 | bpf_printk("active(%i -> %i) map ctx update err: %d\n", |
| 99 | lport, bpf_ntohl(rport), err); |
| 100 | } |
| 101 | break; |
| 102 | default: |
| 103 | break; |
| 104 | } |
| 105 | |
| 106 | return 0; |
| 107 | } |
| 108 | char _license[] SEC("license") = "GPL"; |