xref: /linux-6.15/include/linux/bpf-cgroup.h (revision d4ea45e8)
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/rbtree.h>
10 #include <uapi/linux/bpf.h>
11 
12 struct sock;
13 struct sockaddr;
14 struct cgroup;
15 struct sk_buff;
16 struct bpf_map;
17 struct bpf_prog;
18 struct bpf_sock_ops_kern;
19 struct bpf_cgroup_storage;
20 
21 #ifdef CONFIG_CGROUP_BPF
22 
23 extern struct static_key_false cgroup_bpf_enabled_key;
24 #define cgroup_bpf_enabled static_branch_unlikely(&cgroup_bpf_enabled_key)
25 
26 DECLARE_PER_CPU(struct bpf_cgroup_storage*,
27 		bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
28 
29 #define for_each_cgroup_storage_type(stype) \
30 	for (stype = 0; stype < MAX_BPF_CGROUP_STORAGE_TYPE; stype++)
31 
32 struct bpf_cgroup_storage_map;
33 
34 struct bpf_storage_buffer {
35 	struct rcu_head rcu;
36 	char data[0];
37 };
38 
39 struct bpf_cgroup_storage {
40 	union {
41 		struct bpf_storage_buffer *buf;
42 		void __percpu *percpu_buf;
43 	};
44 	struct bpf_cgroup_storage_map *map;
45 	struct bpf_cgroup_storage_key key;
46 	struct list_head list;
47 	struct rb_node node;
48 	struct rcu_head rcu;
49 };
50 
51 struct bpf_prog_list {
52 	struct list_head node;
53 	struct bpf_prog *prog;
54 	struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE];
55 };
56 
57 struct bpf_prog_array;
58 
59 struct cgroup_bpf {
60 	/* array of effective progs in this cgroup */
61 	struct bpf_prog_array __rcu *effective[MAX_BPF_ATTACH_TYPE];
62 
63 	/* attached progs to this cgroup and attach flags
64 	 * when flags == 0 or BPF_F_ALLOW_OVERRIDE the progs list will
65 	 * have either zero or one element
66 	 * when BPF_F_ALLOW_MULTI the list can have up to BPF_CGROUP_MAX_PROGS
67 	 */
68 	struct list_head progs[MAX_BPF_ATTACH_TYPE];
69 	u32 flags[MAX_BPF_ATTACH_TYPE];
70 
71 	/* temp storage for effective prog array used by prog_attach/detach */
72 	struct bpf_prog_array __rcu *inactive;
73 };
74 
75 void cgroup_bpf_put(struct cgroup *cgrp);
76 int cgroup_bpf_inherit(struct cgroup *cgrp);
77 
78 int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
79 			enum bpf_attach_type type, u32 flags);
80 int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
81 			enum bpf_attach_type type, u32 flags);
82 int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
83 		       union bpf_attr __user *uattr);
84 
85 /* Wrapper for __cgroup_bpf_*() protected by cgroup_mutex */
86 int cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
87 		      enum bpf_attach_type type, u32 flags);
88 int cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
89 		      enum bpf_attach_type type, u32 flags);
90 int cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
91 		     union bpf_attr __user *uattr);
92 
93 int __cgroup_bpf_run_filter_skb(struct sock *sk,
94 				struct sk_buff *skb,
95 				enum bpf_attach_type type);
96 
97 int __cgroup_bpf_run_filter_sk(struct sock *sk,
98 			       enum bpf_attach_type type);
99 
100 int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
101 				      struct sockaddr *uaddr,
102 				      enum bpf_attach_type type,
103 				      void *t_ctx);
104 
105 int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
106 				     struct bpf_sock_ops_kern *sock_ops,
107 				     enum bpf_attach_type type);
108 
109 int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
110 				      short access, enum bpf_attach_type type);
111 
112 static inline enum bpf_cgroup_storage_type cgroup_storage_type(
113 	struct bpf_map *map)
114 {
115 	if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
116 		return BPF_CGROUP_STORAGE_PERCPU;
117 
118 	return BPF_CGROUP_STORAGE_SHARED;
119 }
120 
121 static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage
122 					  *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
123 {
124 	enum bpf_cgroup_storage_type stype;
125 
126 	for_each_cgroup_storage_type(stype)
127 		this_cpu_write(bpf_cgroup_storage[stype], storage[stype]);
128 }
129 
130 struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
131 					enum bpf_cgroup_storage_type stype);
132 void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage);
133 void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,
134 			     struct cgroup *cgroup,
135 			     enum bpf_attach_type type);
136 void bpf_cgroup_storage_unlink(struct bpf_cgroup_storage *storage);
137 int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *map);
138 void bpf_cgroup_storage_release(struct bpf_prog *prog, struct bpf_map *map);
139 
140 int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *value);
141 int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
142 				     void *value, u64 flags);
143 
144 /* Wrappers for __cgroup_bpf_run_filter_skb() guarded by cgroup_bpf_enabled. */
145 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb)			      \
146 ({									      \
147 	int __ret = 0;							      \
148 	if (cgroup_bpf_enabled)						      \
149 		__ret = __cgroup_bpf_run_filter_skb(sk, skb,		      \
150 						    BPF_CGROUP_INET_INGRESS); \
151 									      \
152 	__ret;								      \
153 })
154 
155 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb)			       \
156 ({									       \
157 	int __ret = 0;							       \
158 	if (cgroup_bpf_enabled && sk && sk == skb->sk) {		       \
159 		typeof(sk) __sk = sk_to_full_sk(sk);			       \
160 		if (sk_fullsock(__sk))					       \
161 			__ret = __cgroup_bpf_run_filter_skb(__sk, skb,	       \
162 						      BPF_CGROUP_INET_EGRESS); \
163 	}								       \
164 	__ret;								       \
165 })
166 
167 #define BPF_CGROUP_RUN_SK_PROG(sk, type)				       \
168 ({									       \
169 	int __ret = 0;							       \
170 	if (cgroup_bpf_enabled) {					       \
171 		__ret = __cgroup_bpf_run_filter_sk(sk, type);		       \
172 	}								       \
173 	__ret;								       \
174 })
175 
176 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk)				       \
177 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET_SOCK_CREATE)
178 
179 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk)				       \
180 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET4_POST_BIND)
181 
182 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk)				       \
183 	BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET6_POST_BIND)
184 
185 #define BPF_CGROUP_RUN_SA_PROG(sk, uaddr, type)				       \
186 ({									       \
187 	int __ret = 0;							       \
188 	if (cgroup_bpf_enabled)						       \
189 		__ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
190 							  NULL);	       \
191 	__ret;								       \
192 })
193 
194 #define BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, type, t_ctx)		       \
195 ({									       \
196 	int __ret = 0;							       \
197 	if (cgroup_bpf_enabled)	{					       \
198 		lock_sock(sk);						       \
199 		__ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
200 							  t_ctx);	       \
201 		release_sock(sk);					       \
202 	}								       \
203 	__ret;								       \
204 })
205 
206 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr)			       \
207 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_BIND)
208 
209 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr)			       \
210 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_BIND)
211 
212 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (cgroup_bpf_enabled && \
213 					    sk->sk_prot->pre_connect)
214 
215 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr)			       \
216 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_CONNECT)
217 
218 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr)			       \
219 	BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_CONNECT)
220 
221 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr)		       \
222 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET4_CONNECT, NULL)
223 
224 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr)		       \
225 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET6_CONNECT, NULL)
226 
227 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx)		       \
228 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_SENDMSG, t_ctx)
229 
230 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx)		       \
231 	BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_SENDMSG, t_ctx)
232 
233 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops)				       \
234 ({									       \
235 	int __ret = 0;							       \
236 	if (cgroup_bpf_enabled && (sock_ops)->sk) {	       \
237 		typeof(sk) __sk = sk_to_full_sk((sock_ops)->sk);	       \
238 		if (__sk && sk_fullsock(__sk))				       \
239 			__ret = __cgroup_bpf_run_filter_sock_ops(__sk,	       \
240 								 sock_ops,     \
241 							 BPF_CGROUP_SOCK_OPS); \
242 	}								       \
243 	__ret;								       \
244 })
245 
246 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type, major, minor, access)	      \
247 ({									      \
248 	int __ret = 0;							      \
249 	if (cgroup_bpf_enabled)						      \
250 		__ret = __cgroup_bpf_check_dev_permission(type, major, minor, \
251 							  access,	      \
252 							  BPF_CGROUP_DEVICE); \
253 									      \
254 	__ret;								      \
255 })
256 int cgroup_bpf_prog_attach(const union bpf_attr *attr,
257 			   enum bpf_prog_type ptype, struct bpf_prog *prog);
258 int cgroup_bpf_prog_detach(const union bpf_attr *attr,
259 			   enum bpf_prog_type ptype);
260 int cgroup_bpf_prog_query(const union bpf_attr *attr,
261 			  union bpf_attr __user *uattr);
262 #else
263 
264 struct bpf_prog;
265 struct cgroup_bpf {};
266 static inline void cgroup_bpf_put(struct cgroup *cgrp) {}
267 static inline int cgroup_bpf_inherit(struct cgroup *cgrp) { return 0; }
268 
269 static inline int cgroup_bpf_prog_attach(const union bpf_attr *attr,
270 					 enum bpf_prog_type ptype,
271 					 struct bpf_prog *prog)
272 {
273 	return -EINVAL;
274 }
275 
276 static inline int cgroup_bpf_prog_detach(const union bpf_attr *attr,
277 					 enum bpf_prog_type ptype)
278 {
279 	return -EINVAL;
280 }
281 
282 static inline int cgroup_bpf_prog_query(const union bpf_attr *attr,
283 					union bpf_attr __user *uattr)
284 {
285 	return -EINVAL;
286 }
287 
288 static inline void bpf_cgroup_storage_set(
289 	struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) {}
290 static inline int bpf_cgroup_storage_assign(struct bpf_prog *prog,
291 					    struct bpf_map *map) { return 0; }
292 static inline void bpf_cgroup_storage_release(struct bpf_prog *prog,
293 					      struct bpf_map *map) {}
294 static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(
295 	struct bpf_prog *prog, enum bpf_cgroup_storage_type stype) { return 0; }
296 static inline void bpf_cgroup_storage_free(
297 	struct bpf_cgroup_storage *storage) {}
298 static inline int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key,
299 						 void *value) {
300 	return 0;
301 }
302 static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
303 					void *key, void *value, u64 flags) {
304 	return 0;
305 }
306 
307 #define cgroup_bpf_enabled (0)
308 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (0)
309 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; })
310 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; })
311 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) ({ 0; })
312 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr) ({ 0; })
313 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr) ({ 0; })
314 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk) ({ 0; })
315 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk) ({ 0; })
316 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr) ({ 0; })
317 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr) ({ 0; })
318 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr) ({ 0; })
319 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr) ({ 0; })
320 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
321 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
322 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
323 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
324 
325 #define for_each_cgroup_storage_type(stype) for (; false; )
326 
327 #endif /* CONFIG_CGROUP_BPF */
328 
329 #endif /* _BPF_CGROUP_H */
330