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_skb1")
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_skb2")
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_skb3")
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 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
190 SEC("sockops")
bpf_sockmap(struct bpf_sock_ops * skops)191 int 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
236 SEC("sk_msg1")
bpf_prog4(struct sk_msg_md * msg)237 int 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
266 SEC("sk_msg2")
bpf_prog6(struct sk_msg_md * msg)267 int 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
311 SEC("sk_msg3")
bpf_prog8(struct sk_msg_md * msg)312 int 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 }
332 SEC("sk_msg4")
bpf_prog9(struct sk_msg_md * msg)333 int 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
350 SEC("sk_msg5")
bpf_prog10(struct sk_msg_md * msg)351 int 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
380 char _license[] SEC("license") = "GPL";
381