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