This is xnu-8019. See this file in:
Directory listing for xnu-8019//bsd/security/audit
Makefile
audit.c
audit.h
audit_arg.c
audit_bsd.c
audit_bsd.h
audit_bsm.c
audit_bsm_domain.c
audit_bsm_errno.c
audit_bsm_fcntl.c
audit_bsm_klib.c
audit_bsm_socket_type.c
audit_bsm_token.c
audit_ioctl.h
audit_mac.c
audit_pipe.c
audit_private.h
audit_session.c
audit_syscalls.c
audit_worker.c