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
32 struct {
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
39 struct {
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
46 struct {
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
53 struct {
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
60 struct {
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
67 struct {
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
74 struct {
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
81 struct {
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
88 struct {
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
95 SEC("sk_skb/stream_parser")
bpf_prog1(struct __sk_buff * skb)96 int 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
107 SEC("sk_skb/stream_verdict")
bpf_prog2(struct __sk_buff * skb)108 int 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
bpf_write_pass(struct __sk_buff * skb,int offset)138 static 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
154 SEC("sk_skb/stream_verdict")
bpf_prog3(struct __sk_buff * skb)155 int 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 err = bpf_skb_adjust_room(skb, 4, 0, 0);
181 if (err)
182 return SK_DROP;
183 bpf_write_pass(skb, 13);
184 return ret;
185 }
186
187 SEC("sockops")
bpf_sockmap(struct bpf_sock_ops * skops)188 int bpf_sockmap(struct bpf_sock_ops *skops)
189 {
190 __u32 lport, rport;
191 int op, ret;
192
193 op = (int) skops->op;
194
195 switch (op) {
196 case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
197 lport = skops->local_port;
198 rport = skops->remote_port;
199
200 if (lport == 10000) {
201 ret = 1;
202 #ifdef SOCKMAP
203 bpf_sock_map_update(skops, &sock_map, &ret,
204 BPF_NOEXIST);
205 #else
206 bpf_sock_hash_update(skops, &sock_map, &ret,
207 BPF_NOEXIST);
208 #endif
209 }
210 break;
211 case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
212 lport = skops->local_port;
213 rport = skops->remote_port;
214
215 if (bpf_ntohl(rport) == 10001) {
216 ret = 10;
217 #ifdef SOCKMAP
218 bpf_sock_map_update(skops, &sock_map, &ret,
219 BPF_NOEXIST);
220 #else
221 bpf_sock_hash_update(skops, &sock_map, &ret,
222 BPF_NOEXIST);
223 #endif
224 }
225 break;
226 default:
227 break;
228 }
229
230 return 0;
231 }
232
233 SEC("sk_msg")
bpf_prog4(struct sk_msg_md * msg)234 int bpf_prog4(struct sk_msg_md *msg)
235 {
236 int *bytes, zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5;
237 int *start, *end, *start_push, *end_push, *start_pop, *pop, err = 0;
238
239 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
240 if (bytes)
241 bpf_msg_apply_bytes(msg, *bytes);
242 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
243 if (bytes)
244 bpf_msg_cork_bytes(msg, *bytes);
245 start = bpf_map_lookup_elem(&sock_bytes, &zero);
246 end = bpf_map_lookup_elem(&sock_bytes, &one);
247 if (start && end)
248 bpf_msg_pull_data(msg, *start, *end, 0);
249 start_push = bpf_map_lookup_elem(&sock_bytes, &two);
250 end_push = bpf_map_lookup_elem(&sock_bytes, &three);
251 if (start_push && end_push) {
252 err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
253 if (err)
254 return SK_DROP;
255 }
256 start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
257 pop = bpf_map_lookup_elem(&sock_bytes, &five);
258 if (start_pop && pop)
259 bpf_msg_pop_data(msg, *start_pop, *pop, 0);
260 return SK_PASS;
261 }
262
263 SEC("sk_msg")
bpf_prog6(struct sk_msg_md * msg)264 int bpf_prog6(struct sk_msg_md *msg)
265 {
266 int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, key = 0;
267 int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop, *f;
268 int err = 0;
269 __u64 flags = 0;
270
271 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
272 if (bytes)
273 bpf_msg_apply_bytes(msg, *bytes);
274 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
275 if (bytes)
276 bpf_msg_cork_bytes(msg, *bytes);
277
278 start = bpf_map_lookup_elem(&sock_bytes, &zero);
279 end = bpf_map_lookup_elem(&sock_bytes, &one);
280 if (start && end)
281 bpf_msg_pull_data(msg, *start, *end, 0);
282
283 start_push = bpf_map_lookup_elem(&sock_bytes, &two);
284 end_push = bpf_map_lookup_elem(&sock_bytes, &three);
285 if (start_push && end_push) {
286 err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
287 if (err)
288 return SK_DROP;
289 }
290
291 start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
292 pop = bpf_map_lookup_elem(&sock_bytes, &five);
293 if (start_pop && pop)
294 bpf_msg_pop_data(msg, *start_pop, *pop, 0);
295
296 f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
297 if (f && *f) {
298 key = 2;
299 flags = *f;
300 }
301 #ifdef SOCKMAP
302 return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
303 #else
304 return bpf_msg_redirect_hash(msg, &sock_map_redir, &key, flags);
305 #endif
306 }
307
308 SEC("sk_msg")
bpf_prog8(struct sk_msg_md * msg)309 int bpf_prog8(struct sk_msg_md *msg)
310 {
311 void *data_end = (void *)(long) msg->data_end;
312 void *data = (void *)(long) msg->data;
313 int ret = 0, *bytes, zero = 0;
314
315 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
316 if (bytes) {
317 ret = bpf_msg_apply_bytes(msg, *bytes);
318 if (ret)
319 return SK_DROP;
320 } else {
321 return SK_DROP;
322 }
323
324 __sink(data_end);
325 __sink(data);
326
327 return SK_PASS;
328 }
329
330 SEC("sk_msg")
bpf_prog9(struct sk_msg_md * msg)331 int bpf_prog9(struct sk_msg_md *msg)
332 {
333 void *data_end = (void *)(long) msg->data_end;
334 void *data = (void *)(long) msg->data;
335 int ret = 0, *bytes, zero = 0;
336
337 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
338 if (bytes) {
339 if (((__u64)data_end - (__u64)data) >= *bytes)
340 return SK_PASS;
341 ret = bpf_msg_cork_bytes(msg, *bytes);
342 if (ret)
343 return SK_DROP;
344 }
345 return SK_PASS;
346 }
347
348 SEC("sk_msg")
bpf_prog10(struct sk_msg_md * msg)349 int bpf_prog10(struct sk_msg_md *msg)
350 {
351 int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop;
352 int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, err = 0;
353
354 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
355 if (bytes)
356 bpf_msg_apply_bytes(msg, *bytes);
357 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
358 if (bytes)
359 bpf_msg_cork_bytes(msg, *bytes);
360 start = bpf_map_lookup_elem(&sock_bytes, &zero);
361 end = bpf_map_lookup_elem(&sock_bytes, &one);
362 if (start && end)
363 bpf_msg_pull_data(msg, *start, *end, 0);
364 start_push = bpf_map_lookup_elem(&sock_bytes, &two);
365 end_push = bpf_map_lookup_elem(&sock_bytes, &three);
366 if (start_push && end_push) {
367 err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
368 if (err)
369 return SK_PASS;
370 }
371 start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
372 pop = bpf_map_lookup_elem(&sock_bytes, &five);
373 if (start_pop && pop)
374 bpf_msg_pop_data(msg, *start_pop, *pop, 0);
375 return SK_DROP;
376 }
377
378 char _license[] SEC("license") = "GPL";
379