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[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                         enum bpf_attach_type type, u32 flags);
  89 int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
  90                         enum bpf_attach_type type);
  91 int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
  92                        union bpf_attr __user *uattr);
  93
  94 /* Wrapper for __cgroup_bpf_*() protected by cgroup_mutex */
  95 int cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
  96                       enum bpf_attach_type type, u32 flags);
  97 int cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
  98                       enum bpf_attach_type type, u32 flags);
  99 int cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
 100                      union bpf_attr __user *uattr);
 101
 102 int __cgroup_bpf_run_filter_skb(struct sock *sk,
 103                                 struct sk_buff *skb,
 104                                 enum bpf_attach_type type);
 105
 106 int __cgroup_bpf_run_filter_sk(struct sock *sk,
 107                                enum bpf_attach_type type);
 108
 109 int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
 110                                       struct sockaddr *uaddr,
 111                                       enum bpf_attach_type type,
 112                                       void *t_ctx);
 113
 114 int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
 115                                      struct bpf_sock_ops_kern *sock_ops,
 116                                      enum bpf_attach_type type);
 117
 118 int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
 119                                       short access, enum bpf_attach_type type);
 120
 121 int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
 122                                    struct ctl_table *table, int write,
 123                                    void __user *buf, size_t *pcount,
 124                                    loff_t *ppos, void **new_buf,
 125                                    enum bpf_attach_type type);
 126
 127 static inline enum bpf_cgroup_storage_type cgroup_storage_type(
 128         struct bpf_map *map)
 129 {
 130         if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
 131                 return BPF_CGROUP_STORAGE_PERCPU;
 132
 133         return BPF_CGROUP_STORAGE_SHARED;
 134 }
 135
 136 static inline void bpf_cgroup_storage_set(struct bpf_cgroup_storage
 137                                           *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
 138 {
 139         enum bpf_cgroup_storage_type stype;
 140
 141         for_each_cgroup_storage_type(stype)
 142                 this_cpu_write(bpf_cgroup_storage[stype], storage[stype]);
 143 }
 144
 145 struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
 146                                         enum bpf_cgroup_storage_type stype);
 147 void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage);
 148 void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,
 149                              struct cgroup *cgroup,
 150                              enum bpf_attach_type type);
 151 void bpf_cgroup_storage_unlink(struct bpf_cgroup_storage *storage);
 152 int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *map);
 153 void bpf_cgroup_storage_release(struct bpf_prog *prog, struct bpf_map *map);
 154
 155 int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *value);
 156 int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
 157                                      void *value, u64 flags);
 158
 159 /* Wrappers for __cgroup_bpf_run_filter_skb() guarded by cgroup_bpf_enabled. */
 160 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb)                             \
 161 ({                                                                            \
 162         int __ret = 0;                                                        \
 163         if (cgroup_bpf_enabled)                                               \
 164                 __ret = __cgroup_bpf_run_filter_skb(sk, skb,                  \
 165                                                     BPF_CGROUP_INET_INGRESS); \
 166                                                                               \
 167         __ret;                                                                \
 168 })
 169
 170 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb)                               \
 171 ({                                                                             \
 172         int __ret = 0;                                                         \
 173         if (cgroup_bpf_enabled && sk && sk == skb->sk) {                       \
 174                 typeof(sk) __sk = sk_to_full_sk(sk);                           \
 175                 if (sk_fullsock(__sk))                                         \
 176                         __ret = __cgroup_bpf_run_filter_skb(__sk, skb,         \
 177                                                       BPF_CGROUP_INET_EGRESS); \
 178         }                                                                      \
 179         __ret;                                                                 \
 180 })
 181
 182 #define BPF_CGROUP_RUN_SK_PROG(sk, type)                                       \
 183 ({                                                                             \
 184         int __ret = 0;                                                         \
 185         if (cgroup_bpf_enabled) {                                              \
 186                 __ret = __cgroup_bpf_run_filter_sk(sk, type);                  \
 187         }                                                                      \
 188         __ret;                                                                 \
 189 })
 190
 191 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk)                                      \
 192         BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET_SOCK_CREATE)
 193
 194 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk)                                \
 195         BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET4_POST_BIND)
 196
 197 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk)                                \
 198         BPF_CGROUP_RUN_SK_PROG(sk, BPF_CGROUP_INET6_POST_BIND)
 199
 200 #define BPF_CGROUP_RUN_SA_PROG(sk, uaddr, type)                                \
 201 ({                                                                             \
 202         int __ret = 0;                                                         \
 203         if (cgroup_bpf_enabled)                                                \
 204                 __ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
 205                                                           NULL);               \
 206         __ret;                                                                 \
 207 })
 208
 209 #define BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, type, t_ctx)                    \
 210 ({                                                                             \
 211         int __ret = 0;                                                         \
 212         if (cgroup_bpf_enabled) {                                              \
 213                 lock_sock(sk);                                                 \
 214                 __ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, type,     \
 215                                                           t_ctx);              \
 216                 release_sock(sk);                                              \
 217         }                                                                      \
 218         __ret;                                                                 \
 219 })
 220
 221 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr)                              \
 222         BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_BIND)
 223
 224 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr)                              \
 225         BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_BIND)
 226
 227 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (cgroup_bpf_enabled && \
 228                                             sk->sk_prot->pre_connect)
 229
 230 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr)                           \
 231         BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET4_CONNECT)
 232
 233 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr)                           \
 234         BPF_CGROUP_RUN_SA_PROG(sk, uaddr, BPF_CGROUP_INET6_CONNECT)
 235
 236 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr)                      \
 237         BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET4_CONNECT, NULL)
 238
 239 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr)                      \
 240         BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_INET6_CONNECT, NULL)
 241
 242 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx)                \
 243         BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_SENDMSG, t_ctx)
 244
 245 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx)                \
 246         BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_SENDMSG, t_ctx)
 247
 248 #define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr)                        \
 249         BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP4_RECVMSG, NULL)
 250
 251 #define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr)                        \
 252         BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, BPF_CGROUP_UDP6_RECVMSG, NULL)
 253
 254 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops)                                 \
 255 ({                                                                             \
 256         int __ret = 0;                                                         \
 257         if (cgroup_bpf_enabled && (sock_ops)->sk) {            \
 258                 typeof(sk) __sk = sk_to_full_sk((sock_ops)->sk);               \
 259                 if (__sk && sk_fullsock(__sk))                                 \
 260                         __ret = __cgroup_bpf_run_filter_sock_ops(__sk,         \
 261                                                                  sock_ops,     \
 262                                                          BPF_CGROUP_SOCK_OPS); \
 263         }                                                                      \
 264         __ret;                                                                 \
 265 })
 266
 267 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type, major, minor, access)         \
 268 ({                                                                            \
 269         int __ret = 0;                                                        \
 270         if (cgroup_bpf_enabled)                                               \
 271                 __ret = __cgroup_bpf_check_dev_permission(type, major, minor, \
 272                                                           access,             \
 273                                                           BPF_CGROUP_DEVICE); \
 274                                                                               \
 275         __ret;                                                                \
 276 })
 277
 278
 279 #define BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, buf, count, pos, nbuf)  \
 280 ({                                                                             \
 281         int __ret = 0;                                                         \
 282         if (cgroup_bpf_enabled)                                                \
 283                 __ret = __cgroup_bpf_run_filter_sysctl(head, table, write,     \
 284                                                        buf, count, pos, nbuf,  \
 285                                                        BPF_CGROUP_SYSCTL);     \
 286         __ret;                                                                 \
 287 })
 288
 289 int cgroup_bpf_prog_attach(const union bpf_attr *attr,
 290                            enum bpf_prog_type ptype, struct bpf_prog *prog);
 291 int cgroup_bpf_prog_detach(const union bpf_attr *attr,
 292                            enum bpf_prog_type ptype);
 293 int cgroup_bpf_prog_query(const union bpf_attr *attr,
 294                           union bpf_attr __user *uattr);
 295 #else
 296
 297 struct bpf_prog;
 298 struct cgroup_bpf {};
 299 static inline int cgroup_bpf_inherit(struct cgroup *cgrp) { return 0; }
 300 static inline void cgroup_bpf_offline(struct cgroup *cgrp) {}
 301
 302 static inline int cgroup_bpf_prog_attach(const union bpf_attr *attr,
 303                                          enum bpf_prog_type ptype,
 304                                          struct bpf_prog *prog)
 305 {
 306         return -EINVAL;
 307 }
 308
 309 static inline int cgroup_bpf_prog_detach(const union bpf_attr *attr,
 310                                          enum bpf_prog_type ptype)
 311 {
 312         return -EINVAL;
 313 }
 314
 315 static inline int cgroup_bpf_prog_query(const union bpf_attr *attr,
 316                                         union bpf_attr __user *uattr)
 317 {
 318         return -EINVAL;
 319 }
 320
 321 static inline void bpf_cgroup_storage_set(
 322         struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE]) {}
 323 static inline int bpf_cgroup_storage_assign(struct bpf_prog *prog,
 324                                             struct bpf_map *map) { return 0; }
 325 static inline void bpf_cgroup_storage_release(struct bpf_prog *prog,
 326                                               struct bpf_map *map) {}
 327 static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(
 328         struct bpf_prog *prog, enum bpf_cgroup_storage_type stype) { return NULL; }
 329 static inline void bpf_cgroup_storage_free(
 330         struct bpf_cgroup_storage *storage) {}
 331 static inline int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key,
 332                                                  void *value) {
 333         return 0;
 334 }
 335 static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
 336                                         void *key, void *value, u64 flags) {
 337         return 0;
 338 }
 339
 340 #define cgroup_bpf_enabled (0)
 341 #define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (0)
 342 #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; })
 343 #define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; })
 344 #define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) ({ 0; })
 345 #define BPF_CGROUP_RUN_PROG_INET4_BIND(sk, uaddr) ({ 0; })
 346 #define BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr) ({ 0; })
 347 #define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk) ({ 0; })
 348 #define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk) ({ 0; })
 349 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr) ({ 0; })
 350 #define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr) ({ 0; })
 351 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr) ({ 0; })
 352 #define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr) ({ 0; })
 353 #define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
 354 #define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
 355 #define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr) ({ 0; })
 356 #define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr) ({ 0; })
 357 #define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
 358 #define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(type,major,minor,access) ({ 0; })
 359 #define BPF_CGROUP_RUN_PROG_SYSCTL(head,table,write,buf,count,pos,nbuf) ({ 0; })
 360
 361 #define for_each_cgroup_storage_type(stype) for (; false; )
 362
 363 #endif /* CONFIG_CGROUP_BPF */
 364
 365 #endif /* _BPF_CGROUP_H */