1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 /*
4  * Copyright (C) 2020 Google LLC.
5  */
6 
7 #ifndef _LINUX_BPF_LSM_H
8 #define _LINUX_BPF_LSM_H
9 
10 #include <linux/sched.h>
11 #include <linux/bpf.h>
12 #include <linux/bpf_verifier.h>
13 #include <linux/lsm_hooks.h>
14 
15 #ifdef CONFIG_BPF_LSM
16 
17 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
18 	RET bpf_lsm_##NAME(__VA_ARGS__);
19 #include <linux/lsm_hook_defs.h>
20 #undef LSM_HOOK
21 
22 struct bpf_storage_blob {
23 	struct bpf_local_storage __rcu *storage;
24 };
25 
26 extern struct lsm_blob_sizes bpf_lsm_blob_sizes;
27 
28 int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog,
29 			const struct bpf_prog *prog);
30 
31 bool bpf_lsm_is_sleepable_hook(u32 btf_id);
32 bool bpf_lsm_is_trusted(const struct bpf_prog *prog);
33 
bpf_inode(const struct inode * inode)34 static inline struct bpf_storage_blob *bpf_inode(
35 	const struct inode *inode)
36 {
37 	if (unlikely(!inode->i_security))
38 		return NULL;
39 
40 	return inode->i_security + bpf_lsm_blob_sizes.lbs_inode;
41 }
42 
43 extern const struct bpf_func_proto bpf_inode_storage_get_proto;
44 extern const struct bpf_func_proto bpf_inode_storage_delete_proto;
45 void bpf_inode_storage_free(struct inode *inode);
46 
47 void bpf_lsm_find_cgroup_shim(const struct bpf_prog *prog, bpf_func_t *bpf_func);
48 
49 int bpf_lsm_get_retval_range(const struct bpf_prog *prog,
50 			     struct bpf_retval_range *range);
51 #else /* !CONFIG_BPF_LSM */
52 
bpf_lsm_is_sleepable_hook(u32 btf_id)53 static inline bool bpf_lsm_is_sleepable_hook(u32 btf_id)
54 {
55 	return false;
56 }
57 
bpf_lsm_is_trusted(const struct bpf_prog * prog)58 static inline bool bpf_lsm_is_trusted(const struct bpf_prog *prog)
59 {
60 	return false;
61 }
62 
bpf_lsm_verify_prog(struct bpf_verifier_log * vlog,const struct bpf_prog * prog)63 static inline int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog,
64 				      const struct bpf_prog *prog)
65 {
66 	return -EOPNOTSUPP;
67 }
68 
bpf_inode(const struct inode * inode)69 static inline struct bpf_storage_blob *bpf_inode(
70 	const struct inode *inode)
71 {
72 	return NULL;
73 }
74 
bpf_inode_storage_free(struct inode * inode)75 static inline void bpf_inode_storage_free(struct inode *inode)
76 {
77 }
78 
bpf_lsm_find_cgroup_shim(const struct bpf_prog * prog,bpf_func_t * bpf_func)79 static inline void bpf_lsm_find_cgroup_shim(const struct bpf_prog *prog,
80 					   bpf_func_t *bpf_func)
81 {
82 }
83 
bpf_lsm_get_retval_range(const struct bpf_prog * prog,struct bpf_retval_range * range)84 static inline int bpf_lsm_get_retval_range(const struct bpf_prog *prog,
85 					   struct bpf_retval_range *range)
86 {
87 	return -EOPNOTSUPP;
88 }
89 #endif /* CONFIG_BPF_LSM */
90 
91 #endif /* _LINUX_BPF_LSM_H */
92