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