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_tracing.h>
7 #include <bpf/bpf_endian.h>
8 
9 char _license[] SEC("license") = "GPL";
10 
11 #define IPV6_SEQ_DGRAM_HEADER				\
12 	"  sl  "					\
13 	"local_address                         "	\
14 	"remote_address                        "	\
15 	"st tx_queue rx_queue tr tm->when retrnsmt"	\
16 	"   uid  timeout inode ref pointer drops\n"
17 
18 static long sock_i_ino(const struct sock *sk)
19 {
20 	const struct socket *sk_socket = sk->sk_socket;
21 	const struct inode *inode;
22 	unsigned long ino;
23 
24 	if (!sk_socket)
25 		return 0;
26 
27 	inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
28 	bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
29 	return ino;
30 }
31 
32 SEC("iter/udp")
33 int dump_udp6(struct bpf_iter__udp *ctx)
34 {
35 	struct seq_file *seq = ctx->meta->seq;
36 	struct udp_sock *udp_sk = ctx->udp_sk;
37 	const struct in6_addr *dest, *src;
38 	struct udp6_sock *udp6_sk;
39 	struct inet_sock *inet;
40 	__u16 srcp, destp;
41 	__u32 seq_num;
42 	int rqueue;
43 
44 	if (udp_sk == (void *)0)
45 		return 0;
46 
47 	seq_num = ctx->meta->seq_num;
48 	if (seq_num == 0)
49 		BPF_SEQ_PRINTF(seq, IPV6_SEQ_DGRAM_HEADER);
50 
51 	udp6_sk = bpf_skc_to_udp6_sock(udp_sk);
52 	if (udp6_sk == (void *)0)
53 		return 0;
54 
55 	inet = &udp_sk->inet;
56 	srcp = bpf_ntohs(inet->inet_sport);
57 	destp = bpf_ntohs(inet->inet_dport);
58 	rqueue = inet->sk.sk_rmem_alloc.counter - udp_sk->forward_deficit;
59 	dest  = &inet->sk.sk_v6_daddr;
60 	src   = &inet->sk.sk_v6_rcv_saddr;
61 
62 	BPF_SEQ_PRINTF(seq, "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ",
63 		       ctx->bucket,
64 		       src->s6_addr32[0], src->s6_addr32[1],
65 		       src->s6_addr32[2], src->s6_addr32[3], srcp,
66 		       dest->s6_addr32[0], dest->s6_addr32[1],
67 		       dest->s6_addr32[2], dest->s6_addr32[3], destp);
68 
69 	BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
70 		       inet->sk.sk_state,
71 		       inet->sk.sk_wmem_alloc.refs.counter - 1,
72 		       rqueue,
73 		       0, 0L, 0, ctx->uid, 0,
74 		       sock_i_ino(&inet->sk),
75 		       inet->sk.sk_refcnt.refs.counter, udp_sk,
76 		       inet->sk.sk_drops.counter);
77 
78 	return 0;
79 }
80