include/linux/bpf-cgroup.h

   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 */