1 // SPDX-License-Identifier: GPL-2.0
2 #include <stddef.h>
3 #include <string.h>
4 #include <linux/bpf.h>
5 #include <linux/if_ether.h>
6 #include <linux/if_packet.h>
7 #include <linux/ip.h>
8 #include <linux/ipv6.h>
9 #include <linux/types.h>
10 #include <linux/socket.h>
11 #include <linux/tcp.h>
12 #include <netinet/in.h>
13 #include "bpf_helpers.h"
14 #include "bpf_endian.h"
15 #include "test_tcpnotify.h"
16 
17 struct bpf_map_def SEC("maps") global_map = {
18 	.type = BPF_MAP_TYPE_ARRAY,
19 	.key_size = sizeof(__u32),
20 	.value_size = sizeof(struct tcpnotify_globals),
21 	.max_entries = 4,
22 };
23 
24 struct bpf_map_def SEC("maps") perf_event_map = {
25 	.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
26 	.key_size = sizeof(int),
27 	.value_size = sizeof(__u32),
28 	.max_entries = 2,
29 };
30 
31 int _version SEC("version") = 1;
32 
33 SEC("sockops")
34 int bpf_testcb(struct bpf_sock_ops *skops)
35 {
36 	int rv = -1;
37 	int op;
38 
39 	op = (int) skops->op;
40 
41 	if (bpf_ntohl(skops->remote_port) != TESTPORT) {
42 		skops->reply = -1;
43 		return 0;
44 	}
45 
46 	switch (op) {
47 	case BPF_SOCK_OPS_TIMEOUT_INIT:
48 	case BPF_SOCK_OPS_RWND_INIT:
49 	case BPF_SOCK_OPS_NEEDS_ECN:
50 	case BPF_SOCK_OPS_BASE_RTT:
51 	case BPF_SOCK_OPS_RTO_CB:
52 		rv = 1;
53 		break;
54 
55 	case BPF_SOCK_OPS_TCP_CONNECT_CB:
56 	case BPF_SOCK_OPS_TCP_LISTEN_CB:
57 	case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
58 	case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
59 		bpf_sock_ops_cb_flags_set(skops, (BPF_SOCK_OPS_RETRANS_CB_FLAG|
60 					  BPF_SOCK_OPS_RTO_CB_FLAG));
61 		rv = 1;
62 		break;
63 	case BPF_SOCK_OPS_RETRANS_CB: {
64 			__u32 key = 0;
65 			struct tcpnotify_globals g, *gp;
66 			struct tcp_notifier msg = {
67 				.type = 0xde,
68 				.subtype = 0xad,
69 				.source = 0xbe,
70 				.hash = 0xef,
71 			};
72 
73 			rv = 1;
74 
75 			/* Update results */
76 			gp = bpf_map_lookup_elem(&global_map, &key);
77 			if (!gp)
78 				break;
79 			g = *gp;
80 			g.total_retrans = skops->total_retrans;
81 			g.ncalls++;
82 			bpf_map_update_elem(&global_map, &key, &g,
83 					    BPF_ANY);
84 			bpf_perf_event_output(skops, &perf_event_map,
85 					      BPF_F_CURRENT_CPU,
86 					      &msg, sizeof(msg));
87 		}
88 		break;
89 	default:
90 		rv = -1;
91 	}
92 	skops->reply = rv;
93 	return 1;
94 }
95 char _license[] SEC("license") = "GPL";
96