3 Commits

Author	SHA1	Message	Date
KP Singh	9e4e01dfd3	bpf: lsm: Implement attach, detach and execution ... 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	2020-03-30 01:34:00 +02:00
KP Singh	9d3fdea789	bpf: lsm: Provide attachment points for BPF LSM programs ... When CONFIG_BPF_LSM is enabled, nop functions, bpf_lsm_<hook_name>, are generated for each LSM hook. These functions are initialized as LSM hooks in a subsequent patch. 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> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/bpf/20200329004356.27286-4-kpsingh@chromium.org	2020-03-30 01:34:00 +02:00
KP Singh	fc611f47f2	bpf: Introduce BPF_PROG_TYPE_LSM ... Introduce types and configs for bpf programs that can be attached to LSM hooks. The programs can be enabled by the config option CONFIG_BPF_LSM. 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> Reviewed-by: Thomas Garnier <thgarnie@google.com> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: James Morris <jamorris@linux.microsoft.com> Link: https://lore.kernel.org/bpf/20200329004356.27286-2-kpsingh@chromium.org	2020-03-30 01:34:00 +02:00