master
  1/*-
  2 * SPDX-License-Identifier: BSD-3-Clause
  3 *
  4 * Copyright (c) 1999-2009 Apple Inc.
  5 * Copyright (c) 2016, 2018 Robert N. M. Watson
  6 * All rights reserved.
  7 *
  8 * Portions of this software were developed by BAE Systems, the University of
  9 * Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL
 10 * contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent
 11 * Computing (TC) research program.
 12 *
 13 * Redistribution and use in source and binary forms, with or without
 14 * modification, are permitted provided that the following conditions
 15 * are met:
 16 * 1.  Redistributions of source code must retain the above copyright
 17 *     notice, this list of conditions and the following disclaimer.
 18 * 2.  Redistributions in binary form must reproduce the above copyright
 19 *     notice, this list of conditions and the following disclaimer in the
 20 *     documentation and/or other materials provided with the distribution.
 21 * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
 22 *     its contributors may be used to endorse or promote products derived
 23 *     from this software without specific prior written permission.
 24 *
 25 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 28 * ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR
 29 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 33 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 34 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 35 * POSSIBILITY OF SUCH DAMAGE.
 36 */
 37
 38/*
 39 * This include file contains function prototypes and type definitions used
 40 * within the audit implementation.
 41 */
 42
 43#ifndef _SECURITY_AUDIT_PRIVATE_H_
 44#define	_SECURITY_AUDIT_PRIVATE_H_
 45
 46#ifndef _KERNEL
 47#error "no user-serviceable parts inside"
 48#endif
 49
 50#include <sys/caprights.h>
 51#include <sys/ipc.h>
 52#include <sys/socket.h>
 53#include <sys/ucred.h>
 54
 55#ifdef MALLOC_DECLARE
 56MALLOC_DECLARE(M_AUDITBSM);
 57MALLOC_DECLARE(M_AUDITDATA);
 58MALLOC_DECLARE(M_AUDITPATH);
 59MALLOC_DECLARE(M_AUDITTEXT);
 60MALLOC_DECLARE(M_AUDITGIDSET);
 61#endif
 62
 63/*
 64 * Audit control variables that are usually set/read via system calls and
 65 * used to control various aspects of auditing.
 66 */
 67extern struct au_qctrl		audit_qctrl;
 68extern struct audit_fstat	audit_fstat;
 69extern struct au_mask		audit_nae_mask;
 70extern int			audit_panic_on_write_fail;
 71extern int			audit_fail_stop;
 72extern int			audit_argv;
 73extern int			audit_arge;
 74
 75/*
 76 * Success/failure conditions for the conversion of a kernel audit record to
 77 * BSM format.
 78 */
 79#define	BSM_SUCCESS	0
 80#define	BSM_FAILURE	1
 81#define	BSM_NOAUDIT	2
 82
 83/*
 84 * Defines for the kernel audit record k_ar_commit field.  Flags are set to
 85 * indicate what sort of record it is, and which preselection mechanism
 86 * selected it.
 87 */
 88#define	AR_COMMIT_KERNEL	0x00000001U
 89#define	AR_COMMIT_USER		0x00000010U
 90
 91#define	AR_PRESELECT_TRAIL	0x00001000U
 92#define	AR_PRESELECT_PIPE	0x00002000U
 93
 94#define	AR_PRESELECT_USER_TRAIL	0x00004000U
 95#define	AR_PRESELECT_USER_PIPE	0x00008000U
 96
 97#define	AR_PRESELECT_DTRACE	0x00010000U
 98
 99/*
100 * Audit data is generated as a stream of struct audit_record structures,
101 * linked by struct kaudit_record, and contain storage for possible audit so
102 * that it will not need to be allocated during the processing of a system
103 * call, both improving efficiency and avoiding sleeping at untimely moments.
104 * This structure is converted to BSM format before being written to disk.
105 */
106struct vnode_au_info {
107	mode_t	vn_mode;
108	uid_t	vn_uid;
109	gid_t	vn_gid;
110	u_int32_t vn_dev;		/* XXX dev_t compatibility */
111	long	vn_fsid;		/* XXX uint64_t compatibility */
112	long	vn_fileid;		/* XXX ino_t compatibility */
113	long	vn_gen;
114};
115
116struct groupset {
117	gid_t	*gidset;
118	u_int	 gidset_size;
119};
120
121struct socket_au_info {
122	int		so_domain;
123	int		so_type;
124	int		so_protocol;
125	in_addr_t	so_raddr;	/* Remote address if INET socket. */
126	in_addr_t	so_laddr;	/* Local address if INET socket. */
127	u_short		so_rport;	/* Remote port. */
128	u_short		so_lport;	/* Local port. */
129};
130
131/*
132 * The following is used for A_OLDSETQCTRL and AU_OLDGETQCTRL and a 64-bit
133 * userland.
134 */
135struct au_qctrl64 {
136	u_int64_t	aq64_hiwater;
137	u_int64_t	aq64_lowater;
138	u_int64_t	aq64_bufsz;
139	u_int64_t	aq64_delay;
140	u_int64_t	aq64_minfree;
141};
142typedef	struct au_qctrl64	au_qctrl64_t;
143
144union auditon_udata {
145	char			*au_path;
146	int			au_cond;
147	int			au_flags;
148	int			au_policy;
149	int			au_trigger;
150	int64_t			au_cond64;
151	int64_t			au_policy64;
152	au_evclass_map_t	au_evclass;
153	au_mask_t		au_mask;
154	auditinfo_t		au_auinfo;
155	auditpinfo_t		au_aupinfo;
156	auditpinfo_addr_t	au_aupinfo_addr;
157	au_qctrl_t		au_qctrl;
158	au_qctrl64_t		au_qctrl64;
159	au_stat_t		au_stat;
160	au_fstat_t		au_fstat;
161	auditinfo_addr_t	au_kau_info;
162	au_evname_map_t		au_evname;
163};
164
165struct posix_ipc_perm {
166	uid_t	pipc_uid;
167	gid_t	pipc_gid;
168	mode_t	pipc_mode;
169};
170
171struct audit_record {
172	/* Audit record header. */
173	u_int32_t		ar_magic;
174	int			ar_event;
175	int			ar_retval; /* value returned to the process */
176	int			ar_errno;  /* return status of system call */
177	struct timespec		ar_starttime;
178	struct timespec		ar_endtime;
179	u_int64_t		ar_valid_arg;  /* Bitmask of valid arguments */
180
181	/* Audit subject information. */
182	struct xucred		ar_subj_cred;
183	uid_t			ar_subj_ruid;
184	gid_t			ar_subj_rgid;
185	gid_t			ar_subj_egid;
186	uid_t			ar_subj_auid; /* Audit user ID */
187	pid_t			ar_subj_asid; /* Audit session ID */
188	pid_t			ar_subj_pid;
189	struct au_tid		ar_subj_term;
190	struct au_tid_addr	ar_subj_term_addr;
191	struct au_mask		ar_subj_amask;
192
193	/* Operation arguments. */
194	uid_t			ar_arg_euid;
195	uid_t			ar_arg_ruid;
196	uid_t			ar_arg_suid;
197	gid_t			ar_arg_egid;
198	gid_t			ar_arg_rgid;
199	gid_t			ar_arg_sgid;
200	pid_t			ar_arg_pid;
201	pid_t			ar_arg_asid;
202	struct au_tid		ar_arg_termid;
203	struct au_tid_addr	ar_arg_termid_addr;
204	uid_t			ar_arg_uid;
205	uid_t			ar_arg_auid;
206	gid_t			ar_arg_gid;
207	struct groupset		ar_arg_groups;
208	int			ar_arg_fd;
209	int			ar_arg_atfd1;
210	int			ar_arg_atfd2;
211	int			ar_arg_fflags;
212	mode_t			ar_arg_mode;
213	int			ar_arg_dev;	/* XXX dev_t compatibility */
214	long			ar_arg_value;
215	void			*ar_arg_addr;
216	int			ar_arg_len;
217	int			ar_arg_mask;
218	u_int			ar_arg_signum;
219	char			ar_arg_login[MAXLOGNAME];
220	int			ar_arg_ctlname[CTL_MAXNAME];
221	struct socket_au_info	ar_arg_sockinfo;
222	char			*ar_arg_upath1;
223	char			*ar_arg_upath2;
224	char			*ar_arg_text;
225	struct au_mask		ar_arg_amask;
226	struct vnode_au_info	ar_arg_vnode1;
227	struct vnode_au_info	ar_arg_vnode2;
228	int			ar_arg_cmd;
229	int			ar_arg_svipc_which;
230	int			ar_arg_svipc_cmd;
231	struct ipc_perm		ar_arg_svipc_perm;
232	int			ar_arg_svipc_id;
233	void			*ar_arg_svipc_addr;
234	struct posix_ipc_perm	ar_arg_pipc_perm;
235	union auditon_udata	ar_arg_auditon;
236	char			*ar_arg_argv;
237	int			ar_arg_argc;
238	char			*ar_arg_envv;
239	int			ar_arg_envc;
240	int			ar_arg_exitstatus;
241	int			ar_arg_exitretval;
242	struct sockaddr_storage ar_arg_sockaddr;
243	cap_rights_t		ar_arg_rights;
244	uint32_t		ar_arg_fcntl_rights;
245	char			ar_jailname[MAXHOSTNAMELEN];
246};
247
248/*
249 * Arguments in the audit record are initially not defined; flags are set to
250 * indicate if they are present so they can be included in the audit log
251 * stream only if defined.
252 */
253#define	ARG_EUID		0x0000000000000001ULL
254#define	ARG_RUID		0x0000000000000002ULL
255#define	ARG_SUID		0x0000000000000004ULL
256#define	ARG_EGID		0x0000000000000008ULL
257#define	ARG_RGID		0x0000000000000010ULL
258#define	ARG_SGID		0x0000000000000020ULL
259#define	ARG_PID			0x0000000000000040ULL
260#define	ARG_UID			0x0000000000000080ULL
261#define	ARG_AUID		0x0000000000000100ULL
262#define	ARG_GID			0x0000000000000200ULL
263#define	ARG_FD			0x0000000000000400ULL
264#define	ARG_POSIX_IPC_PERM	0x0000000000000800ULL
265#define	ARG_FFLAGS		0x0000000000001000ULL
266#define	ARG_MODE		0x0000000000002000ULL
267#define	ARG_DEV			0x0000000000004000ULL
268#define	ARG_ADDR		0x0000000000008000ULL
269#define	ARG_LEN			0x0000000000010000ULL
270#define	ARG_MASK		0x0000000000020000ULL
271#define	ARG_SIGNUM		0x0000000000040000ULL
272#define	ARG_LOGIN		0x0000000000080000ULL
273#define	ARG_SADDRINET		0x0000000000100000ULL
274#define	ARG_SADDRINET6		0x0000000000200000ULL
275#define	ARG_SADDRUNIX		0x0000000000400000ULL
276#define	ARG_TERMID_ADDR		0x0000000000800000ULL
277#define	ARG_UNUSED2		0x0000000001000000ULL
278#define	ARG_UPATH1		0x0000000002000000ULL
279#define	ARG_UPATH2		0x0000000004000000ULL
280#define	ARG_TEXT		0x0000000008000000ULL
281#define	ARG_VNODE1		0x0000000010000000ULL
282#define	ARG_VNODE2		0x0000000020000000ULL
283#define	ARG_SVIPC_CMD		0x0000000040000000ULL
284#define	ARG_SVIPC_PERM		0x0000000080000000ULL
285#define	ARG_SVIPC_ID		0x0000000100000000ULL
286#define	ARG_SVIPC_ADDR		0x0000000200000000ULL
287#define	ARG_GROUPSET		0x0000000400000000ULL
288#define	ARG_CMD			0x0000000800000000ULL
289#define	ARG_SOCKINFO		0x0000001000000000ULL
290#define	ARG_ASID		0x0000002000000000ULL
291#define	ARG_TERMID		0x0000004000000000ULL
292#define	ARG_AUDITON		0x0000008000000000ULL
293#define	ARG_VALUE		0x0000010000000000ULL
294#define	ARG_AMASK		0x0000020000000000ULL
295#define	ARG_CTLNAME		0x0000040000000000ULL
296#define	ARG_PROCESS		0x0000080000000000ULL
297#define	ARG_MACHPORT1		0x0000100000000000ULL
298#define	ARG_MACHPORT2		0x0000200000000000ULL
299#define	ARG_EXIT		0x0000400000000000ULL
300#define	ARG_IOVECSTR		0x0000800000000000ULL
301#define	ARG_ARGV		0x0001000000000000ULL
302#define	ARG_ENVV		0x0002000000000000ULL
303#define	ARG_ATFD1		0x0004000000000000ULL
304#define	ARG_ATFD2		0x0008000000000000ULL
305#define	ARG_RIGHTS		0x0010000000000000ULL
306#define	ARG_FCNTL_RIGHTS	0x0020000000000000ULL
307#define	ARG_SVIPC_WHICH		0x0200000000000000ULL
308#define	ARG_NONE		0x0000000000000000ULL
309#define	ARG_ALL			0xFFFFFFFFFFFFFFFFULL
310
311#define	ARG_IS_VALID(kar, arg)	((kar)->k_ar.ar_valid_arg & (arg))
312#define	ARG_SET_VALID(kar, arg) do {					\
313	(kar)->k_ar.ar_valid_arg |= (arg);				\
314} while (0)
315#define	ARG_CLEAR_VALID(kar, arg) do {					\
316	(kar)->k_ar.ar_valid_arg &= ~(arg);				\
317} while (0)
318
319/*
320 * In-kernel version of audit record; the basic record plus queue meta-data.
321 * This record can also have a pointer set to some opaque data that will be
322 * passed through to the audit writing mechanism.
323 */
324struct kaudit_record {
325	struct audit_record		 k_ar;
326	u_int32_t			 k_ar_commit;
327	void				*k_udata;	/* User data. */
328	u_int				 k_ulen;	/* User data length. */
329	struct uthread			*k_uthread;	/* Audited thread. */
330	void				*k_dtaudit_state;
331	TAILQ_ENTRY(kaudit_record)	 k_q;
332};
333TAILQ_HEAD(kaudit_queue, kaudit_record);
334
335/*
336 * Functions to manage the allocation, release, and commit of kernel audit
337 * records.
338 */
339void			 audit_abort(struct kaudit_record *ar);
340void			 audit_commit(struct kaudit_record *ar, int error,
341			    int retval);
342struct kaudit_record	*audit_new(int event, struct thread *td);
343
344/*
345 * Function to update the audit_syscalls_enabled flag, whose value is affected
346 * by configuration of the audit trail/pipe mechanism and DTrace.  Call this
347 * function when any of the inputs to that policy change.
348 */
349void	audit_syscalls_enabled_update(void);
350
351/*
352 * Functions relating to the conversion of internal kernel audit records to
353 * the BSM file format.
354 */
355struct au_record;
356int	 kaudit_to_bsm(struct kaudit_record *kar, struct au_record **pau);
357int	 bsm_rec_verify(void *rec);
358
359/*
360 * Kernel versions of the libbsm audit record functions.
361 */
362void	 kau_free(struct au_record *rec);
363void	 kau_init(void);
364
365/*
366 * Return values for pre-selection and post-selection decisions.
367 */
368#define	AU_PRS_SUCCESS	1
369#define	AU_PRS_FAILURE	2
370#define	AU_PRS_BOTH	(AU_PRS_SUCCESS|AU_PRS_FAILURE)
371
372/*
373 * Data structures relating to the kernel audit queue.  Ideally, these might
374 * be abstracted so that only accessor methods are exposed.
375 */
376extern struct mtx		audit_mtx;
377extern struct cv		audit_watermark_cv;
378extern struct cv		audit_worker_cv;
379extern struct kaudit_queue	audit_q;
380extern int			audit_q_len;
381extern int			audit_pre_q_len;
382extern int			audit_in_failure;
383
384/*
385 * Flags to use on audit files when opening and closing.
386 */
387#define	AUDIT_OPEN_FLAGS	(FWRITE | O_APPEND)
388#define	AUDIT_CLOSE_FLAGS	(FWRITE | O_APPEND)
389
390/*
391 * Audit event-to-name mapping structure, maintained in audit_bsm_klib.c.  It
392 * appears in this header so that the DTrace audit provider can dereference
393 * instances passed back in the au_evname_foreach() callbacks.  Safe access to
394 * its fields requires holding ene_lock (after it is visible in the global
395 * table).
396 *
397 * Locking:
398 * (c) - Constant after inserted in the global table
399 * (l) - Protected by ene_lock
400 * (m) - Protected by evnamemap_lock (audit_bsm_klib.c)
401 * (M) - Writes protected by evnamemap_lock; reads unprotected.
402 */
403struct evname_elem {
404	au_event_t		ene_event;			/* (c) */
405	char			ene_name[EVNAMEMAP_NAME_SIZE];	/* (l) */
406	LIST_ENTRY(evname_elem)	ene_entry;			/* (m) */
407	struct mtx		ene_lock;
408
409	/* DTrace probe IDs; 0 if not yet registered. */
410	uint32_t		ene_commit_probe_id;		/* (M) */
411	uint32_t		ene_bsm_probe_id;		/* (M) */
412
413	/* Flags indicating if the probes enabled or not. */
414	int			ene_commit_probe_enabled;	/* (M) */
415	int			ene_bsm_probe_enabled;		/* (M) */
416};
417
418#define	EVNAME_LOCK(ene)	mtx_lock(&(ene)->ene_lock)
419#define	EVNAME_UNLOCK(ene)	mtx_unlock(&(ene)->ene_lock)
420
421/*
422 * Callback function typedef for the same.
423 */
424typedef	void	(*au_evnamemap_callback_t)(struct evname_elem *ene);
425
426/*
427 * DTrace audit provider (dtaudit) hooks -- to be set non-NULL when the audit
428 * provider is loaded and ready to be called into.
429 */
430extern void	*(*dtaudit_hook_preselect)(au_id_t auid, au_event_t event,
431		    au_class_t class);
432extern int	(*dtaudit_hook_commit)(struct kaudit_record *kar,
433		    au_id_t auid, au_event_t event, au_class_t class,
434		    int sorf);
435extern void	(*dtaudit_hook_bsm)(struct kaudit_record *kar, au_id_t auid,
436		    au_event_t event, au_class_t class, int sorf,
437		    void *bsm_data, size_t bsm_len);
438
439#include <sys/fcntl.h>
440#include <sys/kernel.h>
441#include <sys/malloc.h>
442
443/*
444 * Some of the BSM tokenizer functions take different parameters in the
445 * kernel implementations in order to save the copying of large kernel data
446 * structures.  The prototypes of these functions are declared here.
447 */
448token_t		*kau_to_socket(struct socket_au_info *soi);
449
450/*
451 * audit_klib prototypes
452 */
453int		 au_preselect(au_event_t event, au_class_t class,
454		    au_mask_t *mask_p, int sorf);
455void		 au_evclassmap_init(void);
456void		 au_evclassmap_insert(au_event_t event, au_class_t class);
457au_class_t	 au_event_class(au_event_t event);
458void		 au_evnamemap_init(void);
459void		 au_evnamemap_insert(au_event_t event, const char *name);
460void		 au_evnamemap_foreach(au_evnamemap_callback_t callback);
461struct evname_elem	*au_evnamemap_lookup(au_event_t event);
462int		 au_event_name(au_event_t event, char *name);
463au_event_t	 audit_ctlname_to_sysctlevent(int name[], uint64_t valid_arg);
464au_event_t	 audit_flags_and_error_to_openevent(int oflags, int error);
465au_event_t	 audit_flags_and_error_to_openatevent(int oflags, int error);
466au_event_t	 audit_msgctl_to_event(int cmd);
467au_event_t	 audit_msgsys_to_event(int which);
468au_event_t	 audit_semctl_to_event(int cmd);
469au_event_t	 audit_semsys_to_event(int which);
470au_event_t	 audit_shmsys_to_event(int which);
471void		 audit_canon_path(struct thread *td, int dirfd, char *path,
472		    char *cpath);
473void		 audit_canon_path_vp(struct thread *td, struct vnode *rdir,
474		    struct vnode *cdir, char *path, char *cpath);
475au_event_t	 auditon_command_event(int cmd);
476
477/*
478 * Audit trigger events notify user space of kernel audit conditions
479 * asynchronously.
480 */
481void		 audit_trigger_init(void);
482int		 audit_send_trigger(unsigned int trigger);
483
484/*
485 * Accessor functions to manage global audit state.
486 */
487void	 audit_set_kinfo(struct auditinfo_addr *);
488void	 audit_get_kinfo(struct auditinfo_addr *);
489
490/*
491 * General audit related functions.
492 */
493struct kaudit_record	*currecord(void);
494void			 audit_free(struct kaudit_record *ar);
495void			 audit_shutdown(void *arg, int howto);
496void			 audit_rotate_vnode(struct ucred *cred,
497			    struct vnode *vp);
498void			 audit_worker_init(void);
499
500/*
501 * Audit pipe functions.
502 */
503int	 audit_pipe_preselect(au_id_t auid, au_event_t event,
504	    au_class_t class, int sorf, int trail_select);
505void	 audit_pipe_submit(au_id_t auid, au_event_t event, au_class_t class,
506	    int sorf, int trail_select, void *record, u_int record_len);
507void	 audit_pipe_submit_user(void *record, u_int record_len);
508
509#endif /* ! _SECURITY_AUDIT_PRIVATE_H_ */