ceph_x_encrypt_offset
ceph_x_encrypt_offset(&au->session_key);
dp = *p + ceph_x_encrypt_offset(secret);
tp = *p + ceph_x_encrypt_offset(&th->session_key);
msg_b = p + ceph_x_encrypt_offset(&au->session_key);
blob = enc_buf + ceph_x_encrypt_offset(&xi->secret);
dp = *p + ceph_x_encrypt_offset(&th->session_key);
dp = *p + ceph_x_encrypt_offset(secret);