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 int bpf_set_dentry_xattr_locked(struct dentry *dentry, const char *name__str,
52 				const struct bpf_dynptr *value_p, int flags);
53 int bpf_remove_dentry_xattr_locked(struct dentry *dentry, const char *name__str);
54 bool bpf_lsm_has_d_inode_locked(const struct bpf_prog *prog);
55 
56 #else /* !CONFIG_BPF_LSM */
57 
bpf_lsm_is_sleepable_hook(u32 btf_id)58 static inline bool bpf_lsm_is_sleepable_hook(u32 btf_id)
59 {
60 	return false;
61 }
62 
bpf_lsm_is_trusted(const struct bpf_prog * prog)63 static inline bool bpf_lsm_is_trusted(const struct bpf_prog *prog)
64 {
65 	return false;
66 }
67 
bpf_lsm_verify_prog(struct bpf_verifier_log * vlog,const struct bpf_prog * prog)68 static inline int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog,
69 				      const struct bpf_prog *prog)
70 {
71 	return -EOPNOTSUPP;
72 }
73 
bpf_inode(const struct inode * inode)74 static inline struct bpf_storage_blob *bpf_inode(
75 	const struct inode *inode)
76 {
77 	return NULL;
78 }
79 
bpf_inode_storage_free(struct inode * inode)80 static inline void bpf_inode_storage_free(struct inode *inode)
81 {
82 }
83 
bpf_lsm_find_cgroup_shim(const struct bpf_prog * prog,bpf_func_t * bpf_func)84 static inline void bpf_lsm_find_cgroup_shim(const struct bpf_prog *prog,
85 					   bpf_func_t *bpf_func)
86 {
87 }
88 
bpf_lsm_get_retval_range(const struct bpf_prog * prog,struct bpf_retval_range * range)89 static inline int bpf_lsm_get_retval_range(const struct bpf_prog *prog,
90 					   struct bpf_retval_range *range)
91 {
92 	return -EOPNOTSUPP;
93 }
bpf_set_dentry_xattr_locked(struct dentry * dentry,const char * name__str,const struct bpf_dynptr * value_p,int flags)94 static inline int bpf_set_dentry_xattr_locked(struct dentry *dentry, const char *name__str,
95 					      const struct bpf_dynptr *value_p, int flags)
96 {
97 	return -EOPNOTSUPP;
98 }
bpf_remove_dentry_xattr_locked(struct dentry * dentry,const char * name__str)99 static inline int bpf_remove_dentry_xattr_locked(struct dentry *dentry, const char *name__str)
100 {
101 	return -EOPNOTSUPP;
102 }
bpf_lsm_has_d_inode_locked(const struct bpf_prog * prog)103 static inline bool bpf_lsm_has_d_inode_locked(const struct bpf_prog *prog)
104 {
105 	return false;
106 }
107 #endif /* CONFIG_BPF_LSM */
108 
109 #endif /* _LINUX_BPF_LSM_H */
110