1 // SPDX-License-Identifier: GPL-2.0
4 * Copyright (C) 2020 Google LLC.
7 #include <linux/filter.h>
10 #include <linux/binfmts.h>
11 #include <linux/lsm_hooks.h>
12 #include <linux/bpf_lsm.h>
13 #include <linux/kallsyms.h>
14 #include <linux/bpf_verifier.h>
15 #include <net/bpf_sk_storage.h>
16 #include <linux/bpf_local_storage.h>
17 #include <linux/btf_ids.h>
18 #include <linux/ima.h>
19 #include <linux/bpf-cgroup.h>
21 /* For every LSM hook that allows attachment of BPF programs, declare a nop
22 * function where a BPF program can be attached.
24 #define LSM_HOOK(RET, DEFAULT, NAME, ...) \
25 noinline RET bpf_lsm_##NAME(__VA_ARGS__) \
30 #include <linux/lsm_hook_defs.h>
33 #define LSM_HOOK(RET, DEFAULT, NAME, ...) BTF_ID(func, bpf_lsm_##NAME)
34 BTF_SET_START(bpf_lsm_hooks
)
35 #include <linux/lsm_hook_defs.h>
37 BTF_SET_END(bpf_lsm_hooks
)
39 /* List of LSM hooks that should operate on 'current' cgroup regardless
40 * of function signature.
42 BTF_SET_START(bpf_lsm_current_hooks
)
43 /* operate on freshly allocated sk without any cgroup association */
44 #ifdef CONFIG_SECURITY_NETWORK
45 BTF_ID(func
, bpf_lsm_sk_alloc_security
)
46 BTF_ID(func
, bpf_lsm_sk_free_security
)
48 BTF_SET_END(bpf_lsm_current_hooks
)
50 /* List of LSM hooks that trigger while the socket is properly locked.
52 BTF_SET_START(bpf_lsm_locked_sockopt_hooks
)
53 #ifdef CONFIG_SECURITY_NETWORK
54 BTF_ID(func
, bpf_lsm_socket_sock_rcv_skb
)
55 BTF_ID(func
, bpf_lsm_sock_graft
)
56 BTF_ID(func
, bpf_lsm_inet_csk_clone
)
57 BTF_ID(func
, bpf_lsm_inet_conn_established
)
59 BTF_SET_END(bpf_lsm_locked_sockopt_hooks
)
61 /* List of LSM hooks that trigger while the socket is _not_ locked,
62 * but it's ok to call bpf_{g,s}etsockopt because the socket is still
63 * in the early init phase.
65 BTF_SET_START(bpf_lsm_unlocked_sockopt_hooks
)
66 #ifdef CONFIG_SECURITY_NETWORK
67 BTF_ID(func
, bpf_lsm_socket_post_create
)
68 BTF_ID(func
, bpf_lsm_socket_socketpair
)
70 BTF_SET_END(bpf_lsm_unlocked_sockopt_hooks
)
72 #ifdef CONFIG_CGROUP_BPF
73 void bpf_lsm_find_cgroup_shim(const struct bpf_prog
*prog
,
76 const struct btf_param
*args __maybe_unused
;
78 if (btf_type_vlen(prog
->aux
->attach_func_proto
) < 1 ||
79 btf_id_set_contains(&bpf_lsm_current_hooks
,
80 prog
->aux
->attach_btf_id
)) {
81 *bpf_func
= __cgroup_bpf_run_lsm_current
;
86 args
= btf_params(prog
->aux
->attach_func_proto
);
88 if (args
[0].type
== btf_sock_ids
[BTF_SOCK_TYPE_SOCKET
])
89 *bpf_func
= __cgroup_bpf_run_lsm_socket
;
90 else if (args
[0].type
== btf_sock_ids
[BTF_SOCK_TYPE_SOCK
])
91 *bpf_func
= __cgroup_bpf_run_lsm_sock
;
94 *bpf_func
= __cgroup_bpf_run_lsm_current
;
98 int bpf_lsm_verify_prog(struct bpf_verifier_log
*vlog
,
99 const struct bpf_prog
*prog
)
101 if (!prog
->gpl_compatible
) {
103 "LSM programs must have a GPL compatible license\n");
107 if (!btf_id_set_contains(&bpf_lsm_hooks
, prog
->aux
->attach_btf_id
)) {
108 bpf_log(vlog
, "attach_btf_id %u points to wrong type name %s\n",
109 prog
->aux
->attach_btf_id
, prog
->aux
->attach_func_name
);
116 /* Mask for all the currently supported BPRM option flags */
117 #define BPF_F_BRPM_OPTS_MASK BPF_F_BPRM_SECUREEXEC
119 BPF_CALL_2(bpf_bprm_opts_set
, struct linux_binprm
*, bprm
, u64
, flags
)
121 if (flags
& ~BPF_F_BRPM_OPTS_MASK
)
124 bprm
->secureexec
= (flags
& BPF_F_BPRM_SECUREEXEC
);
128 BTF_ID_LIST_SINGLE(bpf_bprm_opts_set_btf_ids
, struct, linux_binprm
)
130 static const struct bpf_func_proto bpf_bprm_opts_set_proto
= {
131 .func
= bpf_bprm_opts_set
,
133 .ret_type
= RET_INTEGER
,
134 .arg1_type
= ARG_PTR_TO_BTF_ID
,
135 .arg1_btf_id
= &bpf_bprm_opts_set_btf_ids
[0],
136 .arg2_type
= ARG_ANYTHING
,
139 BPF_CALL_3(bpf_ima_inode_hash
, struct inode
*, inode
, void *, dst
, u32
, size
)
141 return ima_inode_hash(inode
, dst
, size
);
144 static bool bpf_ima_inode_hash_allowed(const struct bpf_prog
*prog
)
146 return bpf_lsm_is_sleepable_hook(prog
->aux
->attach_btf_id
);
149 BTF_ID_LIST_SINGLE(bpf_ima_inode_hash_btf_ids
, struct, inode
)
151 static const struct bpf_func_proto bpf_ima_inode_hash_proto
= {
152 .func
= bpf_ima_inode_hash
,
154 .ret_type
= RET_INTEGER
,
155 .arg1_type
= ARG_PTR_TO_BTF_ID
,
156 .arg1_btf_id
= &bpf_ima_inode_hash_btf_ids
[0],
157 .arg2_type
= ARG_PTR_TO_UNINIT_MEM
,
158 .arg3_type
= ARG_CONST_SIZE
,
159 .allowed
= bpf_ima_inode_hash_allowed
,
162 BPF_CALL_3(bpf_ima_file_hash
, struct file
*, file
, void *, dst
, u32
, size
)
164 return ima_file_hash(file
, dst
, size
);
167 BTF_ID_LIST_SINGLE(bpf_ima_file_hash_btf_ids
, struct, file
)
169 static const struct bpf_func_proto bpf_ima_file_hash_proto
= {
170 .func
= bpf_ima_file_hash
,
172 .ret_type
= RET_INTEGER
,
173 .arg1_type
= ARG_PTR_TO_BTF_ID
,
174 .arg1_btf_id
= &bpf_ima_file_hash_btf_ids
[0],
175 .arg2_type
= ARG_PTR_TO_UNINIT_MEM
,
176 .arg3_type
= ARG_CONST_SIZE
,
177 .allowed
= bpf_ima_inode_hash_allowed
,
180 BPF_CALL_1(bpf_get_attach_cookie
, void *, ctx
)
182 struct bpf_trace_run_ctx
*run_ctx
;
184 run_ctx
= container_of(current
->bpf_ctx
, struct bpf_trace_run_ctx
, run_ctx
);
185 return run_ctx
->bpf_cookie
;
188 static const struct bpf_func_proto bpf_get_attach_cookie_proto
= {
189 .func
= bpf_get_attach_cookie
,
191 .ret_type
= RET_INTEGER
,
192 .arg1_type
= ARG_PTR_TO_CTX
,
195 static const struct bpf_func_proto
*
196 bpf_lsm_func_proto(enum bpf_func_id func_id
, const struct bpf_prog
*prog
)
198 const struct bpf_func_proto
*func_proto
;
200 if (prog
->expected_attach_type
== BPF_LSM_CGROUP
) {
201 func_proto
= cgroup_common_func_proto(func_id
, prog
);
207 case BPF_FUNC_inode_storage_get
:
208 return &bpf_inode_storage_get_proto
;
209 case BPF_FUNC_inode_storage_delete
:
210 return &bpf_inode_storage_delete_proto
;
212 case BPF_FUNC_sk_storage_get
:
213 return &bpf_sk_storage_get_proto
;
214 case BPF_FUNC_sk_storage_delete
:
215 return &bpf_sk_storage_delete_proto
;
216 #endif /* CONFIG_NET */
217 case BPF_FUNC_spin_lock
:
218 return &bpf_spin_lock_proto
;
219 case BPF_FUNC_spin_unlock
:
220 return &bpf_spin_unlock_proto
;
221 case BPF_FUNC_bprm_opts_set
:
222 return &bpf_bprm_opts_set_proto
;
223 case BPF_FUNC_ima_inode_hash
:
224 return prog
->aux
->sleepable
? &bpf_ima_inode_hash_proto
: NULL
;
225 case BPF_FUNC_ima_file_hash
:
226 return prog
->aux
->sleepable
? &bpf_ima_file_hash_proto
: NULL
;
227 case BPF_FUNC_get_attach_cookie
:
228 return bpf_prog_has_trampoline(prog
) ? &bpf_get_attach_cookie_proto
: NULL
;
230 case BPF_FUNC_setsockopt
:
231 if (prog
->expected_attach_type
!= BPF_LSM_CGROUP
)
233 if (btf_id_set_contains(&bpf_lsm_locked_sockopt_hooks
,
234 prog
->aux
->attach_btf_id
))
235 return &bpf_sk_setsockopt_proto
;
236 if (btf_id_set_contains(&bpf_lsm_unlocked_sockopt_hooks
,
237 prog
->aux
->attach_btf_id
))
238 return &bpf_unlocked_sk_setsockopt_proto
;
240 case BPF_FUNC_getsockopt
:
241 if (prog
->expected_attach_type
!= BPF_LSM_CGROUP
)
243 if (btf_id_set_contains(&bpf_lsm_locked_sockopt_hooks
,
244 prog
->aux
->attach_btf_id
))
245 return &bpf_sk_getsockopt_proto
;
246 if (btf_id_set_contains(&bpf_lsm_unlocked_sockopt_hooks
,
247 prog
->aux
->attach_btf_id
))
248 return &bpf_unlocked_sk_getsockopt_proto
;
252 return tracing_prog_func_proto(func_id
, prog
);
256 /* The set of hooks which are called without pagefaults disabled and are allowed
257 * to "sleep" and thus can be used for sleepable BPF programs.
259 BTF_SET_START(sleepable_lsm_hooks
)
260 BTF_ID(func
, bpf_lsm_bpf
)
261 BTF_ID(func
, bpf_lsm_bpf_map
)
262 BTF_ID(func
, bpf_lsm_bpf_map_alloc_security
)
263 BTF_ID(func
, bpf_lsm_bpf_map_free_security
)
264 BTF_ID(func
, bpf_lsm_bpf_prog
)
265 BTF_ID(func
, bpf_lsm_bprm_check_security
)
266 BTF_ID(func
, bpf_lsm_bprm_committed_creds
)
267 BTF_ID(func
, bpf_lsm_bprm_committing_creds
)
268 BTF_ID(func
, bpf_lsm_bprm_creds_for_exec
)
269 BTF_ID(func
, bpf_lsm_bprm_creds_from_file
)
270 BTF_ID(func
, bpf_lsm_capget
)
271 BTF_ID(func
, bpf_lsm_capset
)
272 BTF_ID(func
, bpf_lsm_cred_prepare
)
273 BTF_ID(func
, bpf_lsm_file_ioctl
)
274 BTF_ID(func
, bpf_lsm_file_lock
)
275 BTF_ID(func
, bpf_lsm_file_open
)
276 BTF_ID(func
, bpf_lsm_file_receive
)
278 #ifdef CONFIG_SECURITY_NETWORK
279 BTF_ID(func
, bpf_lsm_inet_conn_established
)
280 #endif /* CONFIG_SECURITY_NETWORK */
282 BTF_ID(func
, bpf_lsm_inode_create
)
283 BTF_ID(func
, bpf_lsm_inode_free_security
)
284 BTF_ID(func
, bpf_lsm_inode_getattr
)
285 BTF_ID(func
, bpf_lsm_inode_getxattr
)
286 BTF_ID(func
, bpf_lsm_inode_mknod
)
287 BTF_ID(func
, bpf_lsm_inode_need_killpriv
)
288 BTF_ID(func
, bpf_lsm_inode_post_setxattr
)
289 BTF_ID(func
, bpf_lsm_inode_readlink
)
290 BTF_ID(func
, bpf_lsm_inode_rename
)
291 BTF_ID(func
, bpf_lsm_inode_rmdir
)
292 BTF_ID(func
, bpf_lsm_inode_setattr
)
293 BTF_ID(func
, bpf_lsm_inode_setxattr
)
294 BTF_ID(func
, bpf_lsm_inode_symlink
)
295 BTF_ID(func
, bpf_lsm_inode_unlink
)
296 BTF_ID(func
, bpf_lsm_kernel_module_request
)
297 BTF_ID(func
, bpf_lsm_kernel_read_file
)
298 BTF_ID(func
, bpf_lsm_kernfs_init_security
)
301 BTF_ID(func
, bpf_lsm_key_free
)
302 #endif /* CONFIG_KEYS */
304 BTF_ID(func
, bpf_lsm_mmap_file
)
305 BTF_ID(func
, bpf_lsm_netlink_send
)
306 BTF_ID(func
, bpf_lsm_path_notify
)
307 BTF_ID(func
, bpf_lsm_release_secctx
)
308 BTF_ID(func
, bpf_lsm_sb_alloc_security
)
309 BTF_ID(func
, bpf_lsm_sb_eat_lsm_opts
)
310 BTF_ID(func
, bpf_lsm_sb_kern_mount
)
311 BTF_ID(func
, bpf_lsm_sb_mount
)
312 BTF_ID(func
, bpf_lsm_sb_remount
)
313 BTF_ID(func
, bpf_lsm_sb_set_mnt_opts
)
314 BTF_ID(func
, bpf_lsm_sb_show_options
)
315 BTF_ID(func
, bpf_lsm_sb_statfs
)
316 BTF_ID(func
, bpf_lsm_sb_umount
)
317 BTF_ID(func
, bpf_lsm_settime
)
319 #ifdef CONFIG_SECURITY_NETWORK
320 BTF_ID(func
, bpf_lsm_socket_accept
)
321 BTF_ID(func
, bpf_lsm_socket_bind
)
322 BTF_ID(func
, bpf_lsm_socket_connect
)
323 BTF_ID(func
, bpf_lsm_socket_create
)
324 BTF_ID(func
, bpf_lsm_socket_getpeername
)
325 BTF_ID(func
, bpf_lsm_socket_getpeersec_dgram
)
326 BTF_ID(func
, bpf_lsm_socket_getsockname
)
327 BTF_ID(func
, bpf_lsm_socket_getsockopt
)
328 BTF_ID(func
, bpf_lsm_socket_listen
)
329 BTF_ID(func
, bpf_lsm_socket_post_create
)
330 BTF_ID(func
, bpf_lsm_socket_recvmsg
)
331 BTF_ID(func
, bpf_lsm_socket_sendmsg
)
332 BTF_ID(func
, bpf_lsm_socket_shutdown
)
333 BTF_ID(func
, bpf_lsm_socket_socketpair
)
334 #endif /* CONFIG_SECURITY_NETWORK */
336 BTF_ID(func
, bpf_lsm_syslog
)
337 BTF_ID(func
, bpf_lsm_task_alloc
)
338 BTF_ID(func
, bpf_lsm_current_getsecid_subj
)
339 BTF_ID(func
, bpf_lsm_task_getsecid_obj
)
340 BTF_ID(func
, bpf_lsm_task_prctl
)
341 BTF_ID(func
, bpf_lsm_task_setscheduler
)
342 BTF_ID(func
, bpf_lsm_task_to_inode
)
343 BTF_ID(func
, bpf_lsm_userns_create
)
344 BTF_SET_END(sleepable_lsm_hooks
)
346 bool bpf_lsm_is_sleepable_hook(u32 btf_id
)
348 return btf_id_set_contains(&sleepable_lsm_hooks
, btf_id
);
351 const struct bpf_prog_ops lsm_prog_ops
= {
354 const struct bpf_verifier_ops lsm_verifier_ops
= {
355 .get_func_proto
= bpf_lsm_func_proto
,
356 .is_valid_access
= btf_ctx_access
,