1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 #ifndef _BSM_AUDIT_KERNEL_H
26 #define _BSM_AUDIT_KERNEL_H
27
28
29 /*
30 * This file contains the basic auditing control structure definitions.
31 */
32
33 #include <c2/audit_kevents.h>
34 #include <sys/priv_impl.h>
35 #include <sys/taskq.h>
36 #include <sys/zone.h>
37
38 #include <sys/tsol/label.h>
39
40 #ifdef __cplusplus
41 extern "C" {
42 #endif
43
44 /*
45 * This table contains the mapping from the system call ID to a corresponding
46 * audit event.
47 *
48 * au_init() is a function called at the beginning of the system call that
49 * performs any necessary setup/processing. It maps the call into the
50 * appropriate event, depending on the system call arguments. It is called
51 * by audit_start() from trap.c .
52 *
53 * au_event is the audit event associated with the system call. Most of the
54 * time it will map directly from the system call i.e. There is one system
55 * call associated with the event. In some cases, such as shmsys, or open,
56 * the au_start() function will map the system call to more than one event,
57 * depending on the system call arguments.
58 *
59 * au_start() is a function that provides per system call processing at the
60 * beginning of a system call. It is mainly concerned with preseving the
61 * audit record components that may be altered so that we can determine
62 * what the original paramater was before as well as after the system call.
63 * It is possible that au_start() may be taken away. It might be cleaner to
64 * define flags in au_ctrl to save a designated argument. For the moment we
65 * support both mechanisms, however the use of au_start() will be reviewed
66 * for 4.1.1 and CMW and ZEUS to see if such a general method is justified.
67 *
68 * au_finish() is a function that provides per system call processing at the
69 * completion of a system call. In certain circumstances, the type of audit
70 * event depends on intermidiate results during the processing of the system
71 * call. It is called in audit_finish() from trap.c .
72 *
73 * au_ctrl is a control vector that indicates what processing might have to
74 * be performed, even if there is no auditing for this system call. At
75 * present this is mostly for path processing for chmod, chroot. We need to
76 * process the path information in vfs_lookup, even when we are not auditing
77 * the system call in the case of chdir and chroot.
78 */
79 /*
80 * Defines for au_ctrl
81 */
82 #define S2E_SP TAD_SAVPATH /* save path for later use */
83 #define S2E_MLD TAD_MLD /* only one lookup per system call */
84 #define S2E_NPT TAD_NOPATH /* force no path in audit record */
85 #define S2E_PUB TAD_PUBLIC_EV /* syscall is defined as a public op */
86
87 /*
88 * At present, we are using the audit classes imbedded with in the kernel. Each
89 * event has a bit mask determining which classes the event is associated.
90 * The table audit_e2s maps the audit event ID to the audit state.
91 *
92 * Note that this may change radically. If we use a bit vector for the audit
93 * class, we can allow granularity at the event ID for each user. In this
94 * case, the vector would be determined at user level and passed to the kernel
95 * via the setaudit system call.
96 */
97
98 /*
99 * The audit_pad structure holds paths for the current root and directory
100 * for the process, as well as for open files and directly manipulated objects.
101 * The reference count minimizes data copies since the process's current
102 * directory changes very seldom.
103 */
104 struct audit_path {
105 uint_t audp_ref; /* reference count */
106 uint_t audp_size; /* allocated size of this structure */
107 uint_t audp_cnt; /* number of path sections */
108 char *audp_sect[1]; /* path section pointers */
109 /* audp_sect[0] is the path name */
110 /* audp_sect[1+] are attribute paths */
111 };
112
113 /*
114 * The structure of the terminal ID within the kernel is different from the
115 * terminal ID in user space. It is a combination of port and IP address.
116 */
117
118 struct au_termid {
119 dev_t at_port;
120 uint_t at_type;
121 uint_t at_addr[4];
122 };
123 typedef struct au_termid au_termid_t;
124
125 /*
126 * Attributes for deferring the queuing of an event.
127 */
128 typedef struct au_defer_info {
129 struct au_defer_info *audi_next; /* next on linked list */
130 void *audi_ad; /* audit record */
131 au_event_t audi_e_type; /* audit event id */
132 au_emod_t audi_e_mod; /* audit event modifier */
133 int audi_flag; /* au_close*() flags */
134 timestruc_t audi_atime; /* audit event timestamp */
135 } au_defer_info_t;
136
137 /*
138 * The structure p_audit_data hangs off of the process structure. It contains
139 * all of the audit information necessary to manage the audit record generation
140 * for each process.
141 *
142 * The pad_lock is constructed in the kmem_cache; the rest is combined
143 * in a sub structure so it can be copied/zeroed in one statement.
144 *
145 * The members have been reordered for maximum packing on 64 bit Solaris.
146 */
147 struct p_audit_data {
148 kmutex_t pad_lock; /* lock pad data during changes */
149 struct _pad_data {
150 struct audit_path *pad_root; /* process root path */
151 struct audit_path *pad_cwd; /* process cwd path */
152 au_mask_t pad_newmask; /* pending new mask */
153 int pad_flags;
154 } pad_data;
155 };
156 typedef struct p_audit_data p_audit_data_t;
157
158 #define pad_root pad_data.pad_root
159 #define pad_cwd pad_data.pad_cwd
160 #define pad_newmask pad_data.pad_newmask
161 #define pad_flags pad_data.pad_flags
162
163 /*
164 * Defines for process audit flags (pad_flags)
165 */
166 #define PAD_SETMASK 0x00000001 /* need to complete pending setmask */
167
168 extern kmem_cache_t *au_pad_cache;
169
170 /*
171 * Defines for thread audit control/status flags (tad_ctrl)
172 */
173 #define TAD_ABSPATH 0x00000001 /* path from lookup is absolute */
174 #define TAD_ATCALL 0x00000002 /* *at() syscall, like openat() */
175 #define TAD_ATTPATH 0x00000004 /* attribute file lookup */
176 #define TAD_CORE 0x00000008 /* save attribute during core dump */
177 #define TAD_ERRJMP 0x00000010 /* abort record generation on error */
178 #define TAD_MLD 0x00000020 /* system call involves MLD */
179 #define TAD_NOATTRB 0x00000040 /* do not automatically add attribute */
180 #define TAD_NOAUDIT 0x00000080 /* discard audit record */
181 #define TAD_NOPATH 0x00000100 /* force no paths in audit record */
182 #define TAD_PATHFND 0x00000200 /* found path, don't retry lookup */
183 #define TAD_PUBLIC_EV 0x00000400 /* syscall is defined as a public op */
184 #define TAD_SAVPATH 0x00000800 /* save path for further processing */
185 #define TAD_TRUE_CREATE 0x00001000 /* true create, file not found */
186
187 /*
188 * The structure t_audit_data hangs off of the thread structure. It contains
189 * all of the audit information necessary to manage the audit record generation
190 * for each thread.
191 *
192 */
193
194 struct t_audit_data {
195 kthread_id_t tad_thread; /* DEBUG pointer to parent thread */
196 unsigned int tad_scid; /* system call ID for finish */
197 au_event_t tad_event; /* event for audit record */
198 au_emod_t tad_evmod; /* event modifier for audit record */
199 int tad_ctrl; /* audit control/status flags */
200 void *tad_errjmp; /* error longjmp (audit record aborted) */
201 int tad_flag; /* to audit or not to audit */
202 uint32_t tad_audit; /* auditing enabled/disabled */
203 struct audit_path *tad_aupath; /* captured at vfs_lookup */
204 struct audit_path *tad_atpath; /* openat prefix, path of fd */
205 caddr_t tad_ad; /* base of accumulated audit data */
206 au_defer_info_t *tad_defer_head; /* queue of records to defer */
207 /* until syscall end: */
208 au_defer_info_t *tad_defer_tail; /* tail of defer queue */
209 priv_set_t tad_sprivs; /* saved (success) used privs */
210 priv_set_t tad_fprivs; /* saved (failed) used privs */
211 };
212 typedef struct t_audit_data t_audit_data_t;
213
214 /*
215 * The f_audit_data structure hangs off of the file structure. It contains
216 * three fields of data. The audit ID, the audit state, and a path name.
217 */
218
219 struct f_audit_data {
220 kthread_id_t fad_thread; /* DEBUG creating thread */
221 int fad_flags; /* audit control flags */
222 struct audit_path *fad_aupath; /* path from vfs_lookup */
223 };
224 typedef struct f_audit_data f_audit_data_t;
225
226 #define FAD_READ 0x0001 /* read system call seen */
227 #define FAD_WRITE 0x0002 /* write system call seen */
228
229 #define P2A(p) (p->p_audit_data)
230 #define T2A(t) (t->t_audit_data)
231 #define U2A(u) (curthread->t_audit_data)
232 #define F2A(f) (f->f_audit_data)
233
234 #define u_ad ((U2A(u))->tad_ad)
235 #define ad_ctrl ((U2A(u))->tad_ctrl)
236 #define ad_flag ((U2A(u))->tad_flag)
237
238 #define AU_BUFSIZE 128 /* buffer size for the buffer pool */
239
240 struct au_buff {
241 char buf[AU_BUFSIZE];
242 struct au_buff *next_buf;
243 struct au_buff *next_rec;
244 ushort_t rec_len;
245 uchar_t len;
246 uchar_t flag;
247 };
248
249 typedef struct au_buff au_buff_t;
250
251 /*
252 * Kernel audit queue structure.
253 */
254 struct audit_queue {
255 au_buff_t *head; /* head of queue */
256 au_buff_t *tail; /* tail of queue */
257 ssize_t cnt; /* number elements on queue */
258 size_t hiwater; /* high water mark to block */
259 size_t lowater; /* low water mark to restart */
260 size_t bufsz; /* audit trail write buffer size */
261 size_t buflen; /* audit trail buffer length in use */
262 clock_t delay; /* delay before flushing queue */
263 int wt_block; /* writer is blocked (1) */
264 int rd_block; /* reader is blocked (1) */
265 kmutex_t lock; /* mutex lock for queue modification */
266 kcondvar_t write_cv; /* sleep structure for write block */
267 kcondvar_t read_cv; /* sleep structure for read block */
268 };
269
270
271 union rval;
272 struct audit_s2e {
273 au_event_t (*au_init)(au_event_t);
274 /* convert au_event to real audit event ID */
275
276 int au_event; /* default audit event for this system call */
277 void (*au_start)(struct t_audit_data *);
278 /* pre-system call audit processing */
279 void (*au_finish)(struct t_audit_data *, int, union rval *);
280 /* post-system call audit processing */
281 int au_ctrl; /* control flags for auditing actions */
282 };
283
284 extern struct audit_s2e audit_s2e[];
285
286 #define AUK_VALID 0x5A5A5A5A
287 #define AUK_INVALID 0
288 /*
289 * per zone audit context
290 */
291 struct au_kcontext {
292 uint32_t auk_valid;
293 zoneid_t auk_zid;
294
295 boolean_t auk_hostaddr_valid;
296 int auk_sequence;
297 int auk_auditstate;
298 int auk_output_active;
299 struct vnode *auk_current_vp;
300 uint32_t auk_policy;
301
302 struct audit_queue auk_queue;
303
304 au_dbuf_t *auk_dbuffer; /* auditdoor output */
305
306 au_stat_t auk_statistics;
307
308 k_auditinfo_addr_t auk_info;
309 kmutex_t auk_eagain_mutex; /* door call retry */
310 kcondvar_t auk_eagain_cv;
311
312 taskq_t *auk_taskq; /* output thread */
313
314 /* Only one audit svc per zone at a time */
315 /* With the elimination of auditsvc, can this also go? see 6648414 */
316 kmutex_t auk_svc_lock;
317
318 au_state_t auk_ets[MAX_KEVENTS + 1];
319 };
320 #ifndef AUK_CONTEXT_T
321 #define AUK_CONTEXT_T
322 typedef struct au_kcontext au_kcontext_t;
323 #endif
324
325 extern zone_key_t au_zone_key;
326
327 /*
328 * Kernel auditing external variables
329 */
330 extern uint32_t audit_policy;
331 extern int audit_active;
332
333 extern struct audit_queue au_queue;
334 extern struct p_audit_data *pad0;
335 extern struct t_audit_data *tad0;
336
337 /*
338 * audit_path support routines
339 */
340 void au_pathhold(struct audit_path *);
341 void au_pathrele(struct audit_path *);
342 struct audit_path *au_pathdup(const struct audit_path *, int, int);
343
344 void au_pad_init(void);
345
346 int auditctl(int cmd, caddr_t data, int length);
347 int auditdoor(int fd);
348 int getauid(caddr_t);
349 int setauid(caddr_t);
350 int getaudit(caddr_t);
351 int getaudit_addr(caddr_t, int);
352 int setaudit(caddr_t);
353 int setaudit_addr(caddr_t, int);
354
355 /*
356 * Macros to hide asynchronous, non-blocking audit record start and finish
357 * processing.
358 *
359 * NOTE: must be used in (void) funcction () { ... }
360 */
361
362 #define AUDIT_ASYNC_START(rp, audit_event, sorf) \
363 { \
364 label_t jb; \
365 if (setjmp(&jb)) { \
366 /* cleanup any residual audit data */ \
367 audit_async_drop((caddr_t *)&(rp), 0); \
368 return; \
369 } \
370 /* auditing enabled and we're preselected for this event? */ \
371 if (audit_async_start(&jb, audit_event, sorf)) { \
372 return; \
373 } \
374 }
375
376 #define AUDIT_ASYNC_FINISH(rp, audit_event, event_modifier, event_time) \
377 audit_async_finish((caddr_t *)&(rp), audit_event, event_modifier, \
378 event_time);
379
380
381 #ifdef _KERNEL
382 au_buff_t *au_get_buff(void), *au_free_buff(au_buff_t *);
383 #endif
384
385 /*
386 * Macro for uniform "subject" token(s) generation
387 */
388 #define AUDIT_SETSUBJ_GENERIC(u, c, a, k, p) \
389 (au_write((u), au_to_subject(crgetuid(c), \
390 crgetgid(c), crgetruid(c), crgetrgid(c), \
391 p, (a)->ai_auid, (a)->ai_asid, \
392 &((a)->ai_termid)))); \
393 ((is_system_labeled()) ? au_write((u), \
394 au_to_label(CR_SL((c)))) : (void) 0); \
395 (((k)->auk_policy & AUDIT_GROUP) ? au_write((u),\
396 au_to_groups(crgetgroups(c), \
397 crgetngroups(c))) : (void) 0)
398
399 #define AUDIT_SETSUBJ(u, c, a, k) \
400 AUDIT_SETSUBJ_GENERIC(u, c, a, k, curproc->p_pid)
401
402 #define AUDIT_SETPROC_GENERIC(u, c, a, p) \
403 (au_write((u), au_to_process(crgetuid(c), \
404 crgetgid(c), crgetruid(c), crgetrgid(c), \
405 p, (a)->ai_auid, (a)->ai_asid, \
406 &((a)->ai_termid))));
407
408 #define AUDIT_SETPROC(u, c, a) \
409 AUDIT_SETPROC_GENERIC(u, c, a, curproc->p_pid)
410
411 /*
412 * Macros for type conversion
413 */
414
415 /* au_membuf head, to typed data */
416 #define memtod(x, t) ((t)x->buf)
417
418 /* au_membuf types */
419 #define MT_FREE 0 /* should be on free list */
420 #define MT_DATA 1 /* dynamic (data) allocation */
421
422 /* flags to au_memget */
423 #define DONTWAIT 0
424 #define WAIT 1
425
426 #define AU_PACK 1 /* pack data in au_append_rec() */
427 #define AU_LINK 0 /* link data in au_append_rec() */
428
429 /* flags to async routines */
430 #define AU_BACKEND 1 /* called from softcall backend */
431
432 #ifdef __cplusplus
433 }
434 #endif
435
436 #endif /* _BSM_AUDIT_KERNEL_H */