mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 11:19:37 +00:00
![KP Singh](/assets/img/avatar_default.png)
JITed BPF programs are dynamically attached to the LSM hooks using BPF trampolines. The trampoline prologue generates code to handle conversion of the signature of the hook to the appropriate BPF context. The allocated trampoline programs are attached to the nop functions initialized as LSM hooks. BPF_PROG_TYPE_LSM programs must have a GPL compatible license and and need CAP_SYS_ADMIN (required for loading eBPF programs). Upon attachment: * A BPF fexit trampoline is used for LSM hooks with a void return type. * A BPF fmod_ret trampoline is used for LSM hooks which return an int. The attached programs can override the return value of the bpf LSM hook to indicate a MAC Policy decision. Signed-off-by: KP Singh <kpsingh@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Brendan Jackman <jackmanb@google.com> Reviewed-by: Florent Revest <revest@google.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/bpf/20200329004356.27286-5-kpsingh@chromium.org
33 lines
648 B
C
33 lines
648 B
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
/*
|
|
* Copyright (C) 2020 Google LLC.
|
|
*/
|
|
|
|
#ifndef _LINUX_BPF_LSM_H
|
|
#define _LINUX_BPF_LSM_H
|
|
|
|
#include <linux/bpf.h>
|
|
#include <linux/lsm_hooks.h>
|
|
|
|
#ifdef CONFIG_BPF_LSM
|
|
|
|
#define LSM_HOOK(RET, DEFAULT, NAME, ...) \
|
|
RET bpf_lsm_##NAME(__VA_ARGS__);
|
|
#include <linux/lsm_hook_defs.h>
|
|
#undef LSM_HOOK
|
|
|
|
int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog,
|
|
const struct bpf_prog *prog);
|
|
|
|
#else /* !CONFIG_BPF_LSM */
|
|
|
|
static inline int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog,
|
|
const struct bpf_prog *prog)
|
|
{
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
#endif /* CONFIG_BPF_LSM */
|
|
|
|
#endif /* _LINUX_BPF_LSM_H */
|