1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020 Facebook */
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/udp")
25 int dump_udp4(struct bpf_iter__udp *ctx)
26 {
27 	struct seq_file *seq = ctx->meta->seq;
28 	struct udp_sock *udp_sk = ctx->udp_sk;
29 	struct inet_sock *inet;
30 	__u16 srcp, destp;
31 	__be32 dest, src;
32 	__u32 seq_num;
33 	int rqueue;
34 
35 	if (udp_sk == (void *)0)
36 		return 0;
37 
38 	seq_num = ctx->meta->seq_num;
39 	if (seq_num == 0)
40 		BPF_SEQ_PRINTF(seq,
41 			       "  sl  local_address rem_address   st tx_queue "
42 			       "rx_queue tr tm->when retrnsmt   uid  timeout "
43 			       "inode ref pointer drops\n");
44 
45 	/* filter out udp6 sockets */
46 	inet = &udp_sk->inet;
47 	if (inet->sk.sk_family == AF_INET6)
48 		return 0;
49 
50 	inet = &udp_sk->inet;
51 	dest = inet->inet_daddr;
52 	src = inet->inet_rcv_saddr;
53 	srcp = bpf_ntohs(inet->inet_sport);
54 	destp = bpf_ntohs(inet->inet_dport);
55 	rqueue = inet->sk.sk_rmem_alloc.counter - udp_sk->forward_deficit;
56 
57 	BPF_SEQ_PRINTF(seq, "%5d: %08X:%04X %08X:%04X ",
58 		       ctx->bucket, src, srcp, dest, destp);
59 
60 	BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
61 		       inet->sk.sk_state,
62 		       inet->sk.sk_wmem_alloc.refs.counter - 1,
63 		       rqueue,
64 		       0, 0L, 0, ctx->uid, 0,
65 		       sock_i_ino(&inet->sk),
66 		       inet->sk.sk_refcnt.refs.counter, udp_sk,
67 		       inet->sk.sk_drops.counter);
68 
69 	return 0;
70 }
71