1 // SPDX-License-Identifier: GPL-2.0
2
3 #include "vmlinux.h"
4 #include <bpf/bpf_helpers.h>
5 #include <bpf/bpf_endian.h>
6
7 #include "bpf_tracing_net.h"
8
9 __be16 serv_port = 0;
10
11 int bpf_sock_destroy(struct sock_common *sk) __ksym;
12
13 struct {
14 __uint(type, BPF_MAP_TYPE_ARRAY);
15 __uint(max_entries, 1);
16 __type(key, __u32);
17 __type(value, __u64);
18 } tcp_conn_sockets SEC(".maps");
19
20 struct {
21 __uint(type, BPF_MAP_TYPE_ARRAY);
22 __uint(max_entries, 1);
23 __type(key, __u32);
24 __type(value, __u64);
25 } udp_conn_sockets SEC(".maps");
26
27 SEC("cgroup/connect6")
28 int sock_connect(struct bpf_sock_addr *ctx)
29 {
30 __u64 sock_cookie = 0;
31 int key = 0;
32 __u32 keyc = 0;
33
34 if (ctx->family != AF_INET6 || ctx->user_family != AF_INET6)
35 return 1;
36
37 sock_cookie = bpf_get_socket_cookie(ctx);
38 if (ctx->protocol == IPPROTO_TCP)
39 bpf_map_update_elem(&tcp_conn_sockets, &key, &sock_cookie, 0);
40 else if (ctx->protocol == IPPROTO_UDP)
41 bpf_map_update_elem(&udp_conn_sockets, &keyc, &sock_cookie, 0);
42 else
43 return 1;
44
45 return 1;
46 }
47
48 SEC("iter/tcp")
49 int iter_tcp6_client(struct bpf_iter__tcp *ctx)
50 {
51 struct sock_common *sk_common = ctx->sk_common;
52 __u64 sock_cookie = 0;
53 __u64 *val;
54 int key = 0;
55
56 if (!sk_common)
57 return 0;
58
59 if (sk_common->skc_family != AF_INET6)
60 return 0;
61
62 sock_cookie = bpf_get_socket_cookie(sk_common);
63 val = bpf_map_lookup_elem(&tcp_conn_sockets, &key);
64 if (!val)
65 return 0;
66 /* Destroy connected client sockets. */
67 if (sock_cookie == *val)
68 bpf_sock_destroy(sk_common);
69
70 return 0;
71 }
72
73 SEC("iter/tcp")
74 int iter_tcp6_server(struct bpf_iter__tcp *ctx)
75 {
76 struct sock_common *sk_common = ctx->sk_common;
77 const struct inet_connection_sock *icsk;
78 const struct inet_sock *inet;
79 struct tcp6_sock *tcp_sk;
80 __be16 srcp;
81
82 if (!sk_common)
83 return 0;
84
85 if (sk_common->skc_family != AF_INET6)
86 return 0;
87
88 tcp_sk = bpf_skc_to_tcp6_sock(sk_common);
89 if (!tcp_sk)
90 return 0;
91
92 icsk = &tcp_sk->tcp.inet_conn;
93 inet = &icsk->icsk_inet;
94 srcp = inet->inet_sport;
95
96 /* Destroy server sockets. */
97 if (srcp == serv_port)
98 bpf_sock_destroy(sk_common);
99
100 return 0;
101 }
102
103
104 SEC("iter/udp")
105 int iter_udp6_client(struct bpf_iter__udp *ctx)
106 {
107 struct udp_sock *udp_sk = ctx->udp_sk;
108 struct sock *sk = (struct sock *) udp_sk;
109 __u64 sock_cookie = 0, *val;
110 int key = 0;
111
112 if (!sk)
113 return 0;
114
115 sock_cookie = bpf_get_socket_cookie(sk);
116 val = bpf_map_lookup_elem(&udp_conn_sockets, &key);
117 if (!val)
118 return 0;
119 /* Destroy connected client sockets. */
120 if (sock_cookie == *val)
121 bpf_sock_destroy((struct sock_common *)sk);
122
123 return 0;
124 }
125
126 SEC("iter/udp")
127 int iter_udp6_server(struct bpf_iter__udp *ctx)
128 {
129 struct udp_sock *udp_sk = ctx->udp_sk;
130 struct sock *sk = (struct sock *) udp_sk;
131 struct inet_sock *inet;
132 __be16 srcp;
133
134 if (!sk)
135 return 0;
136
137 inet = &udp_sk->inet;
138 srcp = inet->inet_sport;
139 if (srcp == serv_port)
140 bpf_sock_destroy((struct sock_common *)sk);
141
142 return 0;
143 }
144
145 char _license[] SEC("license") = "GPL";
146
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