> From: Yonghong Song [mailto:yhs@xxxxxx] > Sent: Tuesday, February 15, 2022 6:03 PM > On 2/15/22 4:40 AM, Roberto Sassu wrote: > > ima_file_hash() has been modified to calculate the measurement of a file on > > demand, if it has not been already performed by IMA. For compatibility > > reasons, ima_inode_hash() remains unchanged. > > > > Keep the same approach in eBPF and introduce the new helper > > bpf_ima_file_hash() to take advantage of the modified behavior of > > ima_file_hash(). > > > > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > > --- > > include/uapi/linux/bpf.h | 11 +++++++++++ > > kernel/bpf/bpf_lsm.c | 20 ++++++++++++++++++++ > > tools/include/uapi/linux/bpf.h | 11 +++++++++++ > > 3 files changed, 42 insertions(+) > > > > diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h > > index b0383d371b9a..ba33d5718d6b 100644 > > --- a/include/uapi/linux/bpf.h > > +++ b/include/uapi/linux/bpf.h > > @@ -4648,6 +4648,16 @@ union bpf_attr { > > * **-EOPNOTSUP** if IMA is disabled or **-EINVAL** if > > * invalid arguments are passed. > > * > > + * long bpf_ima_file_hash(struct file *file, void *dst, u32 size) > > + * Description > > + * Returns a calculated IMA hash of the *file*. > > + * If the hash is larger than *size*, then only *size* > > + * bytes will be copied to *dst* > > + * Return > > + * The **hash_algo** is returned on success, > > + * **-EOPNOTSUP** if the hash calculation failed or **-EINVAL** > if > > + * invalid arguments are passed. > > + * > > * struct socket *bpf_sock_from_file(struct file *file) > > * Description > > * If the given file represents a socket, returns the associated > > @@ -5182,6 +5192,7 @@ union bpf_attr { > > FN(bprm_opts_set), \ > > FN(ktime_get_coarse_ns), \ > > FN(ima_inode_hash), \ > > + FN(ima_file_hash), \ > > Please put the above FN(ima_file_hash) to the end of the list. > Otherwise, we have a backward compatability issue. Hi Yonghong sure, will do. Thanks Roberto HUAWEI TECHNOLOGIES Duesseldorf GmbH, HRB 56063 Managing Director: Li Peng, Zhong Ronghua > > FN(sock_from_file), \ > > FN(check_mtu), \ > > FN(for_each_map_elem), \ > > diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c > > index 9e4ecc990647..e8d27af5bbcc 100644 > > --- a/kernel/bpf/bpf_lsm.c > > +++ b/kernel/bpf/bpf_lsm.c > [...]