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
8char _license[] SEC("license") = "GPL";
9
10static 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
24SEC("iter/udp")
25int 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