xref: /linux-6.15/include/linux/bpf-cgroup.h (revision 82d00a93)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BPF_CGROUP_H
3 #define _BPF_CGROUP_H
4 
5 #include <linux/bpf.h>
6 #include <linux/errno.h>
7 #include <linux/jump_label.h>
8 #include <linux/percpu.h>
9 #include <linux/percpu-refcount.h>
10 #include <linux/rbtree.h>
11 #include <uapi/linux/bpf.h>
12 
13 struct sock;
14 struct sockaddr;
15 struct cgroup;
16 struct sk_buff;
17 struct bpf_map;
18 struct bpf_prog;
19 struct bpf_sock_ops_kern;
20 struct bpf_cgroup_storage;
21 struct ctl_table;
22 struct ctl_table_header;
23 
24 #ifdef CONFIG_CGROUP_BPF
25 
26 extern struct static_key_false cgroup_bpf_enabled_key;
27 #define cgroup_bpf_enabled static_branch_unlikely(&cgroup_bpf_enabled_key)
28 
29 DECLARE_PER_CPU(struct bpf_cgroup_storage*,
30 		bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
31 
32 #define for_each_cgroup_storage_type(stype) \
33 	for (stype = 0; stype < MAX_BPF_CGROUP_STORAGE_TYPE; stype++)
34 
35 struct bpf_cgroup_storage_map;
36 
37 struct bpf_storage_buffer {
38 	struct rcu_head rcu;
39 	char data[];
40 };
41 
42 struct bpf_cgroup_storage {
43 	union {
44 		struct bpf_storage_buffer *buf;
45 		void __percpu *percpu_buf;
46 	};
47 	struct bpf_cgroup_storage_map *map;
48 	struct bpf_cgroup_storage_key key;
49 	struct list_head list;
50 	struct rb_node node;
51 	struct rcu_head rcu;
52 };
53 
54 struct bpf_cgroup_link {
55 	struct bpf_link link;
56 	struct cgroup *cgroup;
57 	enum bpf_attach_type type;
58 };
59 
60 extern const struct bpf_link_ops bpf_cgroup_link_lops;
61 
62 struct bpf_prog_list {
63 	struct list_head node;
64 	struct bpf_prog *prog;
65 	struct bpf_cgroup_link *link;
66 	struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE];
67 };
68 
69 struct bpf_prog_array;
70 
71 struct cgroup_bpf {
72 	/* array of effective progs in this cgroup */
73 	struct bpf_prog_array __rcu *effective[MAX_BPF_ATTACH_TYPE];
74 
75 	/* attached progs to this cgroup and attach flags
76 	 * when flags == 0 or BPF_F_ALLOW_OVERRIDE the progs list will
77 	 * have either zero or one element
78 	 * when BPF_F_ALLOW_MULTI the list can have up to BPF_CGROUP_MAX_PROGS
79 	 */
80 	struct list_head progs[MAX_BPF_ATTACH_TYPE];
81 	u32 flags[MAX_BPF_ATTACH_TYPE];
82 
83 	/* temp storage for effective prog array used by prog_attach/detach */
84 	struct bpf_prog_array *inactive;
85 
86 	/* reference counter used to detach bpf programs after cgroup removal */
87 	struct percpu_ref refcnt;
88 
89 	/* cgroup_bpf is released using a work queue */
90 	struct work_struct release_work;
91 };
92 
93 int cgroup_bpf_inherit(struct cgroup *cgrp);
94 void cgroup_bpf_offline(struct cgroup *cgrp);
95 
96 int __cgroup_bpf_attach(struct cgroup *cgrp,
97 			struct bpf_prog *prog, struct bpf_prog *replace_prog,
98 			struct bpf_cgroup_link *link,
99 			enum bpf_attach_type type, u32 flags);
100 int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
101 			struct bpf_cgroup_link *link,
102 			enum bpf_attach_type type);
103 int __cgroup_bpf_replace(struct cgroup *cgrp, struct bpf_cgroup_link *link,
104 			 struct bpf_prog *new_prog);
105 int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
106 		       union bpf_attr __user *uattr);
107 
108 /* Wrapper for __cgroup_bpf_*() protected by cgroup_mutex */
109 int cgroup_bpf_attach(struct cgroup *cgrp,
110 		      struct bpf_prog *prog, struct bpf_prog *replace_prog,
111 		      struct bpf_cgroup_link *link, enum bpf_attach_type type,
112 		      u32 flags);
113 int cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
114 		      enum bpf_attach_type type);
115 int cgroup_bpf_replace(struct bpf_link *link, struct bpf_prog *old_prog,
116 		       struct bpf_prog *new_prog);
117 int cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
118 		     union bpf_attr __user *uattr);
119 
120 int __cgroup_bpf_run_filter_skb(struct sock *sk,
121 				struct sk_buff *skb,
122 				enum bpf_attach_type type);
123 
124 int __cgroup_bpf_run_filter_sk(struct sock *sk,
125 			       enum bpf_attach_type type);
126 
127 int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
128 				      struct sockaddr *uaddr,
129 				      enum bpf_attach_type type,
130 				      void *t_ctx);
131 
132 int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
133 				     struct bpf_sock_ops_kern *sock_ops,
134 				     enum bpf_attach_type type);
135 
136 int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
137 				      short access, enum bpf_attach_type type);
138 
139 int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
140 				   struct ctl_table *table, int write,
141 				   void __user *buf, size_t *pcount,
142 				   loff_t *ppos, void **new_buf,
143 				   enum bpf_attach_type type);
144 
145 int __cgroup_bpf_run_filter_setsockopt(struct sock *sock, int *level,
146 				       int *optname, char __user *optval,
147 				       int *optlen, char **kernel_optval);
148 int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
149 				       int optname, char __user *optval,
150 				       int __user *optlen, int max_optlen,
151 				       int retval);
152 
153 static inline enum bpf_cgroup_storage_type cgroup_storage_type(
154 	struct bpf_map *map)
155 {
156 	if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
157 		return BPF_CGROUP_STORAGE_PERCPU;
158 
159 	return BPF_CGROUP_STORAGE_SHARED;
160 }
161 
162 static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage
163 					  *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
164 {
165 	enum bpf_cgroup_storage_type stype;
166 
167 	for_each_cgroup_storage_type(stype)
168 		this_cpu_write(bpf_cgroup_storage[stype], storage[stype]);
169 }
170 
171 struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
172 					enum bpf_cgroup_storage_type stype);
173 void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage);
174 void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,
175 			     struct cgroup *cgroup,
176 			     enum bpf_attach_type type);
177 void bpf_cgroup_storage_unlink(struct bpf_cgroup_storage *storage);
178 int bpf_cgroup_storage_assign(struct bpf_prog_aux *aux, struct bpf_map *map);
179 void bpf_cgroup_storage_release(struct bpf_prog_aux *aux, struct bpf_map *map);
180 
181 int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *value);
182 int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
183 				     void *value, u64 flags);
184 
185 /* Wrappers for __cgroup_bpf_run_filter_skb() guarded by cgroup_bpf_enabled. */
186 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb)			      \
187 ({									      \
188 	int __ret = 0;							      \
189 	if (cgroup_bpf_enabled)						      \
190 		__ret = __cgroup_bpf_run_filter_skb(sk, skb,		      \
191 						    BPF_CGROUP_INET_INGRESS); \
192 									      \
193 	__ret;								      \
194 })
195 
196 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb)			       \
197 ({									       \
198 	int __ret = 0;							       \
199 	if (cgroup_bpf_enabled && sk && sk == skb->sk) {		       \
200 		typeof(sk) __sk = sk_to_full_sk(sk);			       \
201 		if (sk_fullsock(__sk))					       \
202 			__ret = __cgroup_bpf_run_filter_skb(__sk, skb,	       \
203 						      BPF_CGROUP_INET_EGRESS); \
204 	}								       \
205 	__ret;								       \
206 })
207 
208 #define BPF_CGROUP_RUN_SK_PROG(sk, type)				       \
209 ({									       \
210 	int __ret = 0;							       \
211 	if (cgroup_bpf_enabled) {					       \
212 		__ret = __cgroup_bpf_run_filter_sk(sk, type);		       \
213 	}								       \
214 	__ret;								       \
215 })
216 
217 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk)				       \
218 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET_SOCK_CREATE)
219 
220 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk)				       \
221 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET4_POST_BIND)
222 
223 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk)				       \
224 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET6_POST_BIND)
225 
226 #define BPF_CGROUP_RUN_SA_PROG(sk, uaddr, type)				       \
227 ({									       \
228 	int __ret = 0;							       \
229 	if (cgroup_bpf_enabled)						       \
230 		__ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
231 							  NULL);	       \
232 	__ret;								       \
233 })
234 
235 #define BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, type, t_ctx)		       \
236 ({									       \
237 	int __ret = 0;							       \
238 	if (cgroup_bpf_enabled)	{					       \
239 		lock_sock(sk);						       \
240 		__ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
241 							  t_ctx);	       \
242 		release_sock(sk);					       \
243 	}								       \
244 	__ret;								       \
245 })
246 
247 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr)			       \
248 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_BIND)
249 
250 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr)			       \
251 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_BIND)
252 
253 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (cgroup_bpf_enabled && \
254 					    sk->sk_prot->pre_connect)
255 
256 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr)			       \
257 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_CONNECT)
258 
259 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr)			       \
260 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_CONNECT)
261 
262 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr)		       \
263 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET4_CONNECT, NULL)
264 
265 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr)		       \
266 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET6_CONNECT, NULL)
267 
268 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx)		       \
269 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_SENDMSG, t_ctx)
270 
271 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx)		       \
272 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_SENDMSG, t_ctx)
273 
274 #define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr)			\
275 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_RECVMSG, NULL)
276 
277 #define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr)			\
278 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_RECVMSG, NULL)
279 
280 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops)				       \
281 ({									       \
282 	int __ret = 0;							       \
283 	if (cgroup_bpf_enabled && (sock_ops)->sk) {	       \
284 		typeof(sk) __sk = sk_to_full_sk((sock_ops)->sk);	       \
285 		if (__sk && sk_fullsock(__sk))				       \
286 			__ret = __cgroup_bpf_run_filter_sock_ops(__sk,	       \
287 								 sock_ops,     \
288 							 BPF_CGROUP_SOCK_OPS); \
289 	}								       \
290 	__ret;								       \
291 })
292 
293 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type, major, minor, access)	      \
294 ({									      \
295 	int __ret = 0;							      \
296 	if (cgroup_bpf_enabled)						      \
297 		__ret = __cgroup_bpf_check_dev_permission(type, major, minor, \
298 							  access,	      \
299 							  BPF_CGROUP_DEVICE); \
300 									      \
301 	__ret;								      \
302 })
303 
304 
305 #define BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, buf, count, pos, nbuf)  \
306 ({									       \
307 	int __ret = 0;							       \
308 	if (cgroup_bpf_enabled)						       \
309 		__ret = __cgroup_bpf_run_filter_sysctl(head, table, write,     \
310 						       buf, count, pos, nbuf,  \
311 						       BPF_CGROUP_SYSCTL);     \
312 	__ret;								       \
313 })
314 
315 #define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen,   \
316 				       kernel_optval)			       \
317 ({									       \
318 	int __ret = 0;							       \
319 	if (cgroup_bpf_enabled)						       \
320 		__ret = __cgroup_bpf_run_filter_setsockopt(sock, level,	       \
321 							   optname, optval,    \
322 							   optlen,	       \
323 							   kernel_optval);     \
324 	__ret;								       \
325 })
326 
327 #define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen)			       \
328 ({									       \
329 	int __ret = 0;							       \
330 	if (cgroup_bpf_enabled)						       \
331 		get_user(__ret, optlen);				       \
332 	__ret;								       \
333 })
334 
335 #define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, optlen,   \
336 				       max_optlen, retval)		       \
337 ({									       \
338 	int __ret = retval;						       \
339 	if (cgroup_bpf_enabled)						       \
340 		__ret = __cgroup_bpf_run_filter_getsockopt(sock, level,	       \
341 							   optname, optval,    \
342 							   optlen, max_optlen, \
343 							   retval);	       \
344 	__ret;								       \
345 })
346 
347 int cgroup_bpf_prog_attach(const union bpf_attr *attr,
348 			   enum bpf_prog_type ptype, struct bpf_prog *prog);
349 int cgroup_bpf_prog_detach(const union bpf_attr *attr,
350 			   enum bpf_prog_type ptype);
351 int cgroup_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
352 int cgroup_bpf_prog_query(const union bpf_attr *attr,
353 			  union bpf_attr __user *uattr);
354 #else
355 
356 struct bpf_prog;
357 struct bpf_link;
358 struct cgroup_bpf {};
359 static inline int cgroup_bpf_inherit(struct cgroup *cgrp) { return 0; }
360 static inline void cgroup_bpf_offline(struct cgroup *cgrp) {}
361 
362 static inline int cgroup_bpf_prog_attach(const union bpf_attr *attr,
363 					 enum bpf_prog_type ptype,
364 					 struct bpf_prog *prog)
365 {
366 	return -EINVAL;
367 }
368 
369 static inline int cgroup_bpf_prog_detach(const union bpf_attr *attr,
370 					 enum bpf_prog_type ptype)
371 {
372 	return -EINVAL;
373 }
374 
375 static inline int cgroup_bpf_link_attach(const union bpf_attr *attr,
376 					 struct bpf_prog *prog)
377 {
378 	return -EINVAL;
379 }
380 
381 static inline int cgroup_bpf_replace(struct bpf_link *link,
382 				     struct bpf_prog *old_prog,
383 				     struct bpf_prog *new_prog)
384 {
385 	return -EINVAL;
386 }
387 
388 static inline int cgroup_bpf_prog_query(const union bpf_attr *attr,
389 					union bpf_attr __user *uattr)
390 {
391 	return -EINVAL;
392 }
393 
394 static inline void bpf_cgroup_storage_set(
395 	struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) {}
396 static inline int bpf_cgroup_storage_assign(struct bpf_prog_aux *aux,
397 					    struct bpf_map *map) { return 0; }
398 static inline void bpf_cgroup_storage_release(struct bpf_prog_aux *aux,
399 					      struct bpf_map *map) {}
400 static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(
401 	struct bpf_prog *prog, enum bpf_cgroup_storage_type stype) { return NULL; }
402 static inline void bpf_cgroup_storage_free(
403 	struct bpf_cgroup_storage *storage) {}
404 static inline int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key,
405 						 void *value) {
406 	return 0;
407 }
408 static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
409 					void *key, void *value, u64 flags) {
410 	return 0;
411 }
412 
413 #define cgroup_bpf_enabled (0)
414 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (0)
415 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; })
416 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; })
417 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) ({ 0; })
418 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr) ({ 0; })
419 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr) ({ 0; })
420 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk) ({ 0; })
421 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk) ({ 0; })
422 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr) ({ 0; })
423 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr) ({ 0; })
424 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr) ({ 0; })
425 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr) ({ 0; })
426 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
427 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
428 #define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr) ({ 0; })
429 #define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr) ({ 0; })
430 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
431 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
432 #define BPF_CGROUP_RUN_PROG_SYSCTL(head,table,write,buf,count,pos,nbuf) ({ 0; })
433 #define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) ({ 0; })
434 #define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, \
435 				       optlen, max_optlen, retval) ({ retval; })
436 #define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
437 				       kernel_optval) ({ 0; })
438 
439 #define for_each_cgroup_storage_type(stype) for (; false; )
440 
441 #endif /* CONFIG_CGROUP_BPF */
442 
443 #endif /* _BPF_CGROUP_H */
444