1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright Amazon.com Inc. or its affiliates. */
3 #include "bpf_iter.h"
4 #include "bpf_tracing_net.h"
5 #include <bpf/bpf_helpers.h>
6 #include <bpf/bpf_endian.h>
7 
8 char _license[] SEC("license") = "GPL";
9 
10 static long sock_i_ino(const struct sock *sk)
11 {
12 	const struct socket *sk_socket = sk->sk_socket;
13 	const struct inode *inode;
14 	unsigned long ino;
15 
16 	if (!sk_socket)
17 		return 0;
18 
19 	inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
20 	bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
21 	return ino;
22 }
23 
24 SEC("iter/unix")
25 int dump_unix(struct bpf_iter__unix *ctx)
26 {
27 	struct unix_sock *unix_sk = ctx->unix_sk;
28 	struct sock *sk = (struct sock *)unix_sk;
29 	struct seq_file *seq;
30 	__u32 seq_num;
31 
32 	if (!unix_sk)
33 		return 0;
34 
35 	seq = ctx->meta->seq;
36 	seq_num = ctx->meta->seq_num;
37 	if (seq_num == 0)
38 		BPF_SEQ_PRINTF(seq, "Num               RefCount Protocol Flags    Type St    Inode Path\n");
39 
40 	BPF_SEQ_PRINTF(seq, "%pK: %08X %08X %08X %04X %02X %8lu",
41 		       unix_sk,
42 		       sk->sk_refcnt.refs.counter,
43 		       0,
44 		       sk->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0,
45 		       sk->sk_type,
46 		       sk->sk_socket ?
47 		       (sk->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) :
48 		       (sk->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING),
49 		       sock_i_ino(sk));
50 
51 	if (unix_sk->addr) {
52 		if (unix_sk->addr->name->sun_path[0]) {
53 			BPF_SEQ_PRINTF(seq, " %s", unix_sk->addr->name->sun_path);
54 		} else {
55 			/* The name of the abstract UNIX domain socket starts
56 			 * with '\0' and can contain '\0'.  The null bytes
57 			 * should be escaped as done in unix_seq_show().
58 			 */
59 			__u64 i, len;
60 
61 			len = unix_sk->addr->len - sizeof(short);
62 
63 			BPF_SEQ_PRINTF(seq, " @");
64 
65 			for (i = 1; i < len; i++) {
66 				/* unix_validate_addr() tests this upper bound. */
67 				if (i >= sizeof(struct sockaddr_un))
68 					break;
69 
70 				BPF_SEQ_PRINTF(seq, "%c",
71 					       unix_sk->addr->name->sun_path[i] ?:
72 					       '@');
73 			}
74 		}
75 	}
76 
77 	BPF_SEQ_PRINTF(seq, "\n");
78 
79 	return 0;
80 }
81