xref: /linux-6.15/include/linux/bpf-cgroup.h (revision c75bec79)
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[0];
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_prog_list {
55 	struct list_head node;
56 	struct bpf_prog *prog;
57 	struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE];
58 };
59 
60 struct bpf_prog_array;
61 
62 struct cgroup_bpf {
63 	/* array of effective progs in this cgroup */
64 	struct bpf_prog_array __rcu *effective[MAX_BPF_ATTACH_TYPE];
65 
66 	/* attached progs to this cgroup and attach flags
67 	 * when flags == 0 or BPF_F_ALLOW_OVERRIDE the progs list will
68 	 * have either zero or one element
69 	 * when BPF_F_ALLOW_MULTI the list can have up to BPF_CGROUP_MAX_PROGS
70 	 */
71 	struct list_head progs[MAX_BPF_ATTACH_TYPE];
72 	u32 flags[MAX_BPF_ATTACH_TYPE];
73 
74 	/* temp storage for effective prog array used by prog_attach/detach */
75 	struct bpf_prog_array *inactive;
76 
77 	/* reference counter used to detach bpf programs after cgroup removal */
78 	struct percpu_ref refcnt;
79 
80 	/* cgroup_bpf is released using a work queue */
81 	struct work_struct release_work;
82 };
83 
84 int cgroup_bpf_inherit(struct cgroup *cgrp);
85 void cgroup_bpf_offline(struct cgroup *cgrp);
86 
87 int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
88 			struct bpf_prog *replace_prog,
89 			enum bpf_attach_type type, u32 flags);
90 int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
91 			enum bpf_attach_type type);
92 int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
93 		       union bpf_attr __user *uattr);
94 
95 /* Wrapper for __cgroup_bpf_*() protected by cgroup_mutex */
96 int cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
97 		      struct bpf_prog *replace_prog, enum bpf_attach_type type,
98 		      u32 flags);
99 int cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
100 		      enum bpf_attach_type type, u32 flags);
101 int cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
102 		     union bpf_attr __user *uattr);
103 
104 int __cgroup_bpf_run_filter_skb(struct sock *sk,
105 				struct sk_buff *skb,
106 				enum bpf_attach_type type);
107 
108 int __cgroup_bpf_run_filter_sk(struct sock *sk,
109 			       enum bpf_attach_type type);
110 
111 int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
112 				      struct sockaddr *uaddr,
113 				      enum bpf_attach_type type,
114 				      void *t_ctx);
115 
116 int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
117 				     struct bpf_sock_ops_kern *sock_ops,
118 				     enum bpf_attach_type type);
119 
120 int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
121 				      short access, enum bpf_attach_type type);
122 
123 int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
124 				   struct ctl_table *table, int write,
125 				   void __user *buf, size_t *pcount,
126 				   loff_t *ppos, void **new_buf,
127 				   enum bpf_attach_type type);
128 
129 int __cgroup_bpf_run_filter_setsockopt(struct sock *sock, int *level,
130 				       int *optname, char __user *optval,
131 				       int *optlen, char **kernel_optval);
132 int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
133 				       int optname, char __user *optval,
134 				       int __user *optlen, int max_optlen,
135 				       int retval);
136 
137 static inline enum bpf_cgroup_storage_type cgroup_storage_type(
138 	struct bpf_map *map)
139 {
140 	if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
141 		return BPF_CGROUP_STORAGE_PERCPU;
142 
143 	return BPF_CGROUP_STORAGE_SHARED;
144 }
145 
146 static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage
147 					  *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
148 {
149 	enum bpf_cgroup_storage_type stype;
150 
151 	for_each_cgroup_storage_type(stype)
152 		this_cpu_write(bpf_cgroup_storage[stype], storage[stype]);
153 }
154 
155 struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
156 					enum bpf_cgroup_storage_type stype);
157 void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage);
158 void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,
159 			     struct cgroup *cgroup,
160 			     enum bpf_attach_type type);
161 void bpf_cgroup_storage_unlink(struct bpf_cgroup_storage *storage);
162 int bpf_cgroup_storage_assign(struct bpf_prog_aux *aux, struct bpf_map *map);
163 void bpf_cgroup_storage_release(struct bpf_prog_aux *aux, struct bpf_map *map);
164 
165 int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *value);
166 int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
167 				     void *value, u64 flags);
168 
169 /* Wrappers for __cgroup_bpf_run_filter_skb() guarded by cgroup_bpf_enabled. */
170 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb)			      \
171 ({									      \
172 	int __ret = 0;							      \
173 	if (cgroup_bpf_enabled)						      \
174 		__ret = __cgroup_bpf_run_filter_skb(sk, skb,		      \
175 						    BPF_CGROUP_INET_INGRESS); \
176 									      \
177 	__ret;								      \
178 })
179 
180 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb)			       \
181 ({									       \
182 	int __ret = 0;							       \
183 	if (cgroup_bpf_enabled && sk && sk == skb->sk) {		       \
184 		typeof(sk) __sk = sk_to_full_sk(sk);			       \
185 		if (sk_fullsock(__sk))					       \
186 			__ret = __cgroup_bpf_run_filter_skb(__sk, skb,	       \
187 						      BPF_CGROUP_INET_EGRESS); \
188 	}								       \
189 	__ret;								       \
190 })
191 
192 #define BPF_CGROUP_RUN_SK_PROG(sk, type)				       \
193 ({									       \
194 	int __ret = 0;							       \
195 	if (cgroup_bpf_enabled) {					       \
196 		__ret = __cgroup_bpf_run_filter_sk(sk, type);		       \
197 	}								       \
198 	__ret;								       \
199 })
200 
201 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk)				       \
202 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET_SOCK_CREATE)
203 
204 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk)				       \
205 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET4_POST_BIND)
206 
207 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk)				       \
208 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET6_POST_BIND)
209 
210 #define BPF_CGROUP_RUN_SA_PROG(sk, uaddr, type)				       \
211 ({									       \
212 	int __ret = 0;							       \
213 	if (cgroup_bpf_enabled)						       \
214 		__ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
215 							  NULL);	       \
216 	__ret;								       \
217 })
218 
219 #define BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, type, t_ctx)		       \
220 ({									       \
221 	int __ret = 0;							       \
222 	if (cgroup_bpf_enabled)	{					       \
223 		lock_sock(sk);						       \
224 		__ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
225 							  t_ctx);	       \
226 		release_sock(sk);					       \
227 	}								       \
228 	__ret;								       \
229 })
230 
231 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr)			       \
232 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_BIND)
233 
234 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr)			       \
235 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_BIND)
236 
237 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (cgroup_bpf_enabled && \
238 					    sk->sk_prot->pre_connect)
239 
240 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr)			       \
241 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_CONNECT)
242 
243 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr)			       \
244 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_CONNECT)
245 
246 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr)		       \
247 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET4_CONNECT, NULL)
248 
249 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr)		       \
250 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET6_CONNECT, NULL)
251 
252 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx)		       \
253 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_SENDMSG, t_ctx)
254 
255 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx)		       \
256 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_SENDMSG, t_ctx)
257 
258 #define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr)			\
259 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_RECVMSG, NULL)
260 
261 #define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr)			\
262 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_RECVMSG, NULL)
263 
264 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops)				       \
265 ({									       \
266 	int __ret = 0;							       \
267 	if (cgroup_bpf_enabled && (sock_ops)->sk) {	       \
268 		typeof(sk) __sk = sk_to_full_sk((sock_ops)->sk);	       \
269 		if (__sk && sk_fullsock(__sk))				       \
270 			__ret = __cgroup_bpf_run_filter_sock_ops(__sk,	       \
271 								 sock_ops,     \
272 							 BPF_CGROUP_SOCK_OPS); \
273 	}								       \
274 	__ret;								       \
275 })
276 
277 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type, major, minor, access)	      \
278 ({									      \
279 	int __ret = 0;							      \
280 	if (cgroup_bpf_enabled)						      \
281 		__ret = __cgroup_bpf_check_dev_permission(type, major, minor, \
282 							  access,	      \
283 							  BPF_CGROUP_DEVICE); \
284 									      \
285 	__ret;								      \
286 })
287 
288 
289 #define BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, buf, count, pos, nbuf)  \
290 ({									       \
291 	int __ret = 0;							       \
292 	if (cgroup_bpf_enabled)						       \
293 		__ret = __cgroup_bpf_run_filter_sysctl(head, table, write,     \
294 						       buf, count, pos, nbuf,  \
295 						       BPF_CGROUP_SYSCTL);     \
296 	__ret;								       \
297 })
298 
299 #define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen,   \
300 				       kernel_optval)			       \
301 ({									       \
302 	int __ret = 0;							       \
303 	if (cgroup_bpf_enabled)						       \
304 		__ret = __cgroup_bpf_run_filter_setsockopt(sock, level,	       \
305 							   optname, optval,    \
306 							   optlen,	       \
307 							   kernel_optval);     \
308 	__ret;								       \
309 })
310 
311 #define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen)			       \
312 ({									       \
313 	int __ret = 0;							       \
314 	if (cgroup_bpf_enabled)						       \
315 		get_user(__ret, optlen);				       \
316 	__ret;								       \
317 })
318 
319 #define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, optlen,   \
320 				       max_optlen, retval)		       \
321 ({									       \
322 	int __ret = retval;						       \
323 	if (cgroup_bpf_enabled)						       \
324 		__ret = __cgroup_bpf_run_filter_getsockopt(sock, level,	       \
325 							   optname, optval,    \
326 							   optlen, max_optlen, \
327 							   retval);	       \
328 	__ret;								       \
329 })
330 
331 int cgroup_bpf_prog_attach(const union bpf_attr *attr,
332 			   enum bpf_prog_type ptype, struct bpf_prog *prog);
333 int cgroup_bpf_prog_detach(const union bpf_attr *attr,
334 			   enum bpf_prog_type ptype);
335 int cgroup_bpf_prog_query(const union bpf_attr *attr,
336 			  union bpf_attr __user *uattr);
337 #else
338 
339 struct bpf_prog;
340 struct cgroup_bpf {};
341 static inline int cgroup_bpf_inherit(struct cgroup *cgrp) { return 0; }
342 static inline void cgroup_bpf_offline(struct cgroup *cgrp) {}
343 
344 static inline int cgroup_bpf_prog_attach(const union bpf_attr *attr,
345 					 enum bpf_prog_type ptype,
346 					 struct bpf_prog *prog)
347 {
348 	return -EINVAL;
349 }
350 
351 static inline int cgroup_bpf_prog_detach(const union bpf_attr *attr,
352 					 enum bpf_prog_type ptype)
353 {
354 	return -EINVAL;
355 }
356 
357 static inline int cgroup_bpf_prog_query(const union bpf_attr *attr,
358 					union bpf_attr __user *uattr)
359 {
360 	return -EINVAL;
361 }
362 
363 static inline void bpf_cgroup_storage_set(
364 	struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) {}
365 static inline int bpf_cgroup_storage_assign(struct bpf_prog_aux *aux,
366 					    struct bpf_map *map) { return 0; }
367 static inline void bpf_cgroup_storage_release(struct bpf_prog_aux *aux,
368 					      struct bpf_map *map) {}
369 static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(
370 	struct bpf_prog *prog, enum bpf_cgroup_storage_type stype) { return NULL; }
371 static inline void bpf_cgroup_storage_free(
372 	struct bpf_cgroup_storage *storage) {}
373 static inline int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key,
374 						 void *value) {
375 	return 0;
376 }
377 static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
378 					void *key, void *value, u64 flags) {
379 	return 0;
380 }
381 
382 #define cgroup_bpf_enabled (0)
383 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (0)
384 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; })
385 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; })
386 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) ({ 0; })
387 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr) ({ 0; })
388 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr) ({ 0; })
389 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk) ({ 0; })
390 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk) ({ 0; })
391 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr) ({ 0; })
392 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr) ({ 0; })
393 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr) ({ 0; })
394 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr) ({ 0; })
395 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
396 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
397 #define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr) ({ 0; })
398 #define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr) ({ 0; })
399 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
400 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
401 #define BPF_CGROUP_RUN_PROG_SYSCTL(head,table,write,buf,count,pos,nbuf) ({ 0; })
402 #define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) ({ 0; })
403 #define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, \
404 				       optlen, max_optlen, retval) ({ retval; })
405 #define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
406 				       kernel_optval) ({ 0; })
407 
408 #define for_each_cgroup_storage_type(stype) for (; false; )
409 
410 #endif /* CONFIG_CGROUP_BPF */
411 
412 #endif /* _BPF_CGROUP_H */
413