1/* SPDX-License-Identifier: GPL-2.0 */
2/* Copyright (c) 2017-2018 Covalent IO, Inc. http://covalent.io */
3#include <stddef.h>
4#include <string.h>
5#include <linux/bpf.h>
6#include <linux/if_ether.h>
7#include <linux/if_packet.h>
8#include <linux/ip.h>
9#include <linux/ipv6.h>
10#include <linux/in.h>
11#include <linux/udp.h>
12#include <linux/tcp.h>
13#include <linux/pkt_cls.h>
14#include <sys/socket.h>
15#include <bpf/bpf_helpers.h>
16#include <bpf/bpf_endian.h>
17#include "bpf_misc.h"
18
19/* Sockmap sample program connects a client and a backend together
20 * using cgroups.
21 *
22 *    client:X <---> frontend:80 client:X <---> backend:80
23 *
24 * For simplicity we hard code values here and bind 1:1. The hard
25 * coded values are part of the setup in sockmap.sh script that
26 * is associated with this BPF program.
27 *
28 * The bpf_printk is verbose and prints information as connections
29 * are established and verdicts are decided.
30 */
31
32struct {
33	__uint(type, TEST_MAP_TYPE);
34	__uint(max_entries, 20);
35	__uint(key_size, sizeof(int));
36	__uint(value_size, sizeof(int));
37} sock_map SEC(".maps");
38
39struct {
40	__uint(type, TEST_MAP_TYPE);
41	__uint(max_entries, 20);
42	__uint(key_size, sizeof(int));
43	__uint(value_size, sizeof(int));
44} sock_map_txmsg SEC(".maps");
45
46struct {
47	__uint(type, TEST_MAP_TYPE);
48	__uint(max_entries, 20);
49	__uint(key_size, sizeof(int));
50	__uint(value_size, sizeof(int));
51} sock_map_redir SEC(".maps");
52
53struct {
54	__uint(type, BPF_MAP_TYPE_ARRAY);
55	__uint(max_entries, 1);
56	__type(key, int);
57	__type(value, int);
58} sock_apply_bytes SEC(".maps");
59
60struct {
61	__uint(type, BPF_MAP_TYPE_ARRAY);
62	__uint(max_entries, 1);
63	__type(key, int);
64	__type(value, int);
65} sock_cork_bytes SEC(".maps");
66
67struct {
68	__uint(type, BPF_MAP_TYPE_ARRAY);
69	__uint(max_entries, 6);
70	__type(key, int);
71	__type(value, int);
72} sock_bytes SEC(".maps");
73
74struct {
75	__uint(type, BPF_MAP_TYPE_ARRAY);
76	__uint(max_entries, 1);
77	__type(key, int);
78	__type(value, int);
79} sock_redir_flags SEC(".maps");
80
81struct {
82	__uint(type, BPF_MAP_TYPE_ARRAY);
83	__uint(max_entries, 3);
84	__type(key, int);
85	__type(value, int);
86} sock_skb_opts SEC(".maps");
87
88struct {
89	__uint(type, TEST_MAP_TYPE);
90	__uint(max_entries, 20);
91	__uint(key_size, sizeof(int));
92	__uint(value_size, sizeof(int));
93} tls_sock_map SEC(".maps");
94
95SEC("sk_skb1")
96int bpf_prog1(struct __sk_buff *skb)
97{
98	int *f, two = 2;
99
100	f = bpf_map_lookup_elem(&sock_skb_opts, &two);
101	if (f && *f) {
102		return *f;
103	}
104	return skb->len;
105}
106
107SEC("sk_skb2")
108int bpf_prog2(struct __sk_buff *skb)
109{
110	__u32 lport = skb->local_port;
111	__u32 rport = skb->remote_port;
112	int len, *f, ret, zero = 0;
113	__u64 flags = 0;
114
115	__sink(rport);
116	if (lport == 10000)
117		ret = 10;
118	else
119		ret = 1;
120
121	len = (__u32)skb->data_end - (__u32)skb->data;
122	__sink(len);
123
124	f = bpf_map_lookup_elem(&sock_skb_opts, &zero);
125	if (f && *f) {
126		ret = 3;
127		flags = *f;
128	}
129
130#ifdef SOCKMAP
131	return bpf_sk_redirect_map(skb, &sock_map, ret, flags);
132#else
133	return bpf_sk_redirect_hash(skb, &sock_map, &ret, flags);
134#endif
135
136}
137
138static inline void bpf_write_pass(struct __sk_buff *skb, int offset)
139{
140	int err = bpf_skb_pull_data(skb, 6 + offset);
141	void *data_end;
142	char *c;
143
144	if (err)
145		return;
146
147	c = (char *)(long)skb->data;
148	data_end = (void *)(long)skb->data_end;
149
150	if (c + 5 + offset < data_end)
151		memcpy(c + offset, "PASS", 4);
152}
153
154SEC("sk_skb3")
155int bpf_prog3(struct __sk_buff *skb)
156{
157	int err, *f, ret = SK_PASS;
158	const int one = 1;
159
160	f = bpf_map_lookup_elem(&sock_skb_opts, &one);
161	if (f && *f) {
162		__u64 flags = 0;
163
164		ret = 0;
165		flags = *f;
166
167		err = bpf_skb_adjust_room(skb, -13, 0, 0);
168		if (err)
169			return SK_DROP;
170		err = bpf_skb_adjust_room(skb, 4, 0, 0);
171		if (err)
172			return SK_DROP;
173		bpf_write_pass(skb, 0);
174#ifdef SOCKMAP
175		return bpf_sk_redirect_map(skb, &tls_sock_map, ret, flags);
176#else
177		return bpf_sk_redirect_hash(skb, &tls_sock_map, &ret, flags);
178#endif
179	}
180	f = bpf_map_lookup_elem(&sock_skb_opts, &one);
181	if (f && *f)
182		ret = SK_DROP;
183	err = bpf_skb_adjust_room(skb, 4, 0, 0);
184	if (err)
185		return SK_DROP;
186	bpf_write_pass(skb, 13);
187	return ret;
188}
189
190SEC("sockops")
191int bpf_sockmap(struct bpf_sock_ops *skops)
192{
193	__u32 lport, rport;
194	int op, ret;
195
196	op = (int) skops->op;
197
198	switch (op) {
199	case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
200		lport = skops->local_port;
201		rport = skops->remote_port;
202
203		if (lport == 10000) {
204			ret = 1;
205#ifdef SOCKMAP
206			bpf_sock_map_update(skops, &sock_map, &ret,
207						  BPF_NOEXIST);
208#else
209			bpf_sock_hash_update(skops, &sock_map, &ret,
210						   BPF_NOEXIST);
211#endif
212		}
213		break;
214	case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
215		lport = skops->local_port;
216		rport = skops->remote_port;
217
218		if (bpf_ntohl(rport) == 10001) {
219			ret = 10;
220#ifdef SOCKMAP
221			bpf_sock_map_update(skops, &sock_map, &ret,
222						  BPF_NOEXIST);
223#else
224			bpf_sock_hash_update(skops, &sock_map, &ret,
225						   BPF_NOEXIST);
226#endif
227		}
228		break;
229	default:
230		break;
231	}
232
233	return 0;
234}
235
236SEC("sk_msg1")
237int bpf_prog4(struct sk_msg_md *msg)
238{
239	int *bytes, zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5;
240	int *start, *end, *start_push, *end_push, *start_pop, *pop, err = 0;
241
242	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
243	if (bytes)
244		bpf_msg_apply_bytes(msg, *bytes);
245	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
246	if (bytes)
247		bpf_msg_cork_bytes(msg, *bytes);
248	start = bpf_map_lookup_elem(&sock_bytes, &zero);
249	end = bpf_map_lookup_elem(&sock_bytes, &one);
250	if (start && end)
251		bpf_msg_pull_data(msg, *start, *end, 0);
252	start_push = bpf_map_lookup_elem(&sock_bytes, &two);
253	end_push = bpf_map_lookup_elem(&sock_bytes, &three);
254	if (start_push && end_push) {
255		err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
256		if (err)
257			return SK_DROP;
258	}
259	start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
260	pop = bpf_map_lookup_elem(&sock_bytes, &five);
261	if (start_pop && pop)
262		bpf_msg_pop_data(msg, *start_pop, *pop, 0);
263	return SK_PASS;
264}
265
266SEC("sk_msg2")
267int bpf_prog6(struct sk_msg_md *msg)
268{
269	int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, key = 0;
270	int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop, *f;
271	int err = 0;
272	__u64 flags = 0;
273
274	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
275	if (bytes)
276		bpf_msg_apply_bytes(msg, *bytes);
277	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
278	if (bytes)
279		bpf_msg_cork_bytes(msg, *bytes);
280
281	start = bpf_map_lookup_elem(&sock_bytes, &zero);
282	end = bpf_map_lookup_elem(&sock_bytes, &one);
283	if (start && end)
284		bpf_msg_pull_data(msg, *start, *end, 0);
285
286	start_push = bpf_map_lookup_elem(&sock_bytes, &two);
287	end_push = bpf_map_lookup_elem(&sock_bytes, &three);
288	if (start_push && end_push) {
289		err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
290		if (err)
291			return SK_DROP;
292	}
293
294	start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
295	pop = bpf_map_lookup_elem(&sock_bytes, &five);
296	if (start_pop && pop)
297		bpf_msg_pop_data(msg, *start_pop, *pop, 0);
298
299	f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
300	if (f && *f) {
301		key = 2;
302		flags = *f;
303	}
304#ifdef SOCKMAP
305	return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
306#else
307	return bpf_msg_redirect_hash(msg, &sock_map_redir, &key, flags);
308#endif
309}
310
311SEC("sk_msg3")
312int bpf_prog8(struct sk_msg_md *msg)
313{
314	void *data_end = (void *)(long) msg->data_end;
315	void *data = (void *)(long) msg->data;
316	int ret = 0, *bytes, zero = 0;
317
318	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
319	if (bytes) {
320		ret = bpf_msg_apply_bytes(msg, *bytes);
321		if (ret)
322			return SK_DROP;
323	} else {
324		return SK_DROP;
325	}
326
327	__sink(data_end);
328	__sink(data);
329
330	return SK_PASS;
331}
332SEC("sk_msg4")
333int bpf_prog9(struct sk_msg_md *msg)
334{
335	void *data_end = (void *)(long) msg->data_end;
336	void *data = (void *)(long) msg->data;
337	int ret = 0, *bytes, zero = 0;
338
339	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
340	if (bytes) {
341		if (((__u64)data_end - (__u64)data) >= *bytes)
342			return SK_PASS;
343		ret = bpf_msg_cork_bytes(msg, *bytes);
344		if (ret)
345			return SK_DROP;
346	}
347	return SK_PASS;
348}
349
350SEC("sk_msg5")
351int bpf_prog10(struct sk_msg_md *msg)
352{
353	int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop;
354	int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, err = 0;
355
356	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
357	if (bytes)
358		bpf_msg_apply_bytes(msg, *bytes);
359	bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
360	if (bytes)
361		bpf_msg_cork_bytes(msg, *bytes);
362	start = bpf_map_lookup_elem(&sock_bytes, &zero);
363	end = bpf_map_lookup_elem(&sock_bytes, &one);
364	if (start && end)
365		bpf_msg_pull_data(msg, *start, *end, 0);
366	start_push = bpf_map_lookup_elem(&sock_bytes, &two);
367	end_push = bpf_map_lookup_elem(&sock_bytes, &three);
368	if (start_push && end_push) {
369		err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
370		if (err)
371			return SK_PASS;
372	}
373	start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
374	pop = bpf_map_lookup_elem(&sock_bytes, &five);
375	if (start_pop && pop)
376		bpf_msg_pop_data(msg, *start_pop, *pop, 0);
377	return SK_DROP;
378}
379
380char _license[] SEC("license") = "GPL";
381