xref: /netbsd-src/sys/kern/kern_veriexec.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: kern_veriexec.c,v 1.26 2020/06/11 02:30:21 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 2005, 2006 Elad Efrat <elad@NetBSD.org>
5  * Copyright (c) 2005, 2006 Brett Lymn <blymn@NetBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the authors may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: kern_veriexec.c,v 1.26 2020/06/11 02:30:21 thorpej Exp $");
33 
34 #include "opt_veriexec.h"
35 
36 #include <sys/param.h>
37 #include <sys/mount.h>
38 #include <sys/kmem.h>
39 #include <sys/vnode.h>
40 #include <sys/namei.h>
41 #include <sys/once.h>
42 #include <sys/proc.h>
43 #include <sys/rwlock.h>
44 #include <sys/syslog.h>
45 #include <sys/sysctl.h>
46 #include <sys/inttypes.h>
47 #include <sys/verified_exec.h>
48 #include <sys/sha1.h>
49 #include <sys/sha2.h>
50 #include <sys/rmd160.h>
51 #include <sys/md5.h>
52 #include <sys/fileassoc.h>
53 #include <sys/kauth.h>
54 #include <sys/conf.h>
55 #include <miscfs/specfs/specdev.h>
56 #include <prop/proplib.h>
57 #include <sys/fcntl.h>
58 
59 /* Readable values for veriexec_file_report(). */
60 #define	REPORT_ALWAYS		0x01	/* Always print */
61 #define	REPORT_VERBOSE		0x02	/* Print when verbose >= 1 */
62 #define	REPORT_DEBUG		0x04	/* Print when verbose >= 2 (debug) */
63 #define	REPORT_PANIC		0x08	/* Call panic() */
64 #define	REPORT_ALARM		0x10	/* Alarm - also print pid/uid/.. */
65 #define	REPORT_LOGMASK		(REPORT_ALWAYS|REPORT_VERBOSE|REPORT_DEBUG)
66 
67 /* state of locking for veriexec_file_verify */
68 #define VERIEXEC_UNLOCKED	0x00	/* Nothing locked, callee does it */
69 #define VERIEXEC_LOCKED		0x01	/* Global op lock held */
70 
71 /* state of file locking for veriexec_file_verify */
72 #define VERIEXEC_FILE_UNLOCKED	0x02	/* Nothing locked, callee does it */
73 #define VERIEXEC_FILE_LOCKED	0x04	/* File locked */
74 
75 #define VERIEXEC_RW_UPGRADE(lock)	while((rw_tryupgrade(lock)) == 0){};
76 
77 struct veriexec_fpops {
78 	const char *type;
79 	size_t hash_len;
80 	size_t context_size;
81 	veriexec_fpop_init_t init;
82 	veriexec_fpop_update_t update;
83 	veriexec_fpop_final_t final;
84 	LIST_ENTRY(veriexec_fpops) entries;
85 };
86 
87 /* Veriexec per-file entry data. */
88 struct veriexec_file_entry {
89 	krwlock_t lock;				/* r/w lock */
90 	u_char *filename;			/* File name. */
91 	u_char type;				/* Entry type. */
92 	u_char status;				/* Evaluation status. */
93 	u_char *fp;				/* Fingerprint. */
94 	struct veriexec_fpops *ops;		/* Fingerprint ops vector*/
95 	size_t filename_len;			/* Length of filename. */
96 };
97 
98 /* Veriexec per-table data. */
99 struct veriexec_table_entry {
100 	uint64_t vte_count;			/* Number of Veriexec entries. */
101 	const struct sysctlnode *vte_node;
102 };
103 
104 static int veriexec_verbose;
105 static int veriexec_strict;
106 static int veriexec_bypass = 1;
107 
108 static char *veriexec_fp_names = NULL;
109 static size_t veriexec_name_max = 0;
110 
111 static const struct sysctlnode *veriexec_count_node;
112 
113 static fileassoc_t veriexec_hook;
114 static specificdata_key_t veriexec_mountspecific_key;
115 
116 static LIST_HEAD(, veriexec_fpops) veriexec_fpops_list =
117 	LIST_HEAD_INITIALIZER(veriexec_fpops_list);
118 
119 static int veriexec_raw_cb(kauth_cred_t, kauth_action_t, void *,
120     void *, void *, void *, void *);
121 static struct veriexec_fpops *veriexec_fpops_lookup(const char *);
122 static void veriexec_file_free(struct veriexec_file_entry *);
123 
124 static unsigned int veriexec_tablecount = 0;
125 
126 /*
127  * Veriexec operations global lock - most ops hold this as a read
128  * lock, it is upgraded to a write lock when destroying veriexec file
129  * table entries.
130  */
131 static krwlock_t veriexec_op_lock;
132 
133 /*
134  * Sysctl helper routine for Veriexec.
135  */
136 static int
137 sysctl_kern_veriexec_algorithms(SYSCTLFN_ARGS)
138 {
139 	size_t len;
140 	int error;
141 	const char *p;
142 
143 	if (newp != NULL)
144 		return EPERM;
145 
146 	if (namelen != 0)
147 		return EINVAL;
148 
149 	p = veriexec_fp_names == NULL ? "" : veriexec_fp_names;
150 
151 	len = strlen(p) + 1;
152 
153 	if (*oldlenp < len && oldp)
154 		return ENOMEM;
155 
156 	if (oldp && (error = copyout(p, oldp, len)) != 0)
157 		return error;
158 
159 	*oldlenp = len;
160 	return 0;
161 }
162 
163 static int
164 sysctl_kern_veriexec_strict(SYSCTLFN_ARGS)
165 {
166 	struct sysctlnode node;
167 	int error, newval;
168 
169 	node = *rnode;
170 	node.sysctl_data = &newval;
171 
172 	newval = veriexec_strict;
173 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
174 	if (error || newp == NULL)
175 		return error;
176 
177 	if (newval < veriexec_strict)
178 		return EPERM;
179 
180 	veriexec_strict = newval;
181 
182 	return 0;
183 }
184 
185 SYSCTL_SETUP(sysctl_kern_veriexec_setup, "sysctl kern.veriexec setup")
186 {
187 	const struct sysctlnode *rnode = NULL;
188 
189 	sysctl_createv(clog, 0, NULL, &rnode,
190 		       CTLFLAG_PERMANENT,
191 		       CTLTYPE_NODE, "veriexec",
192 		       SYSCTL_DESCR("Veriexec"),
193 		       NULL, 0, NULL, 0,
194 		       CTL_KERN, CTL_CREATE, CTL_EOL);
195 
196 	sysctl_createv(clog, 0, &rnode, NULL,
197 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
198 		       CTLTYPE_INT, "verbose",
199 		       SYSCTL_DESCR("Veriexec verbose level"),
200 		       NULL, 0, &veriexec_verbose, 0,
201 		       CTL_CREATE, CTL_EOL);
202 	sysctl_createv(clog, 0, &rnode, NULL,
203 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
204 		       CTLTYPE_INT, "strict",
205 		       SYSCTL_DESCR("Veriexec strict level"),
206 		       sysctl_kern_veriexec_strict, 0, NULL, 0,
207 		       CTL_CREATE, CTL_EOL);
208 	sysctl_createv(clog, 0, &rnode, NULL,
209 		       CTLFLAG_PERMANENT,
210 		       CTLTYPE_STRING, "algorithms",
211 		       SYSCTL_DESCR("Veriexec supported hashing "
212 				    "algorithms"),
213 		       sysctl_kern_veriexec_algorithms, 0, NULL, 0,
214 		       CTL_CREATE, CTL_EOL);
215 	sysctl_createv(clog, 0, &rnode, &veriexec_count_node,
216 		       CTLFLAG_PERMANENT,
217 		       CTLTYPE_NODE, "count",
218 		       SYSCTL_DESCR("Number of fingerprints on mount(s)"),
219 		       NULL, 0, NULL, 0,
220 		       CTL_CREATE, CTL_EOL);
221 }
222 
223 /*
224  * Add ops to the fingerprint ops vector list.
225  */
226 int
227 veriexec_fpops_add(const char *fp_type, size_t hash_len, size_t ctx_size,
228     veriexec_fpop_init_t init, veriexec_fpop_update_t update,
229     veriexec_fpop_final_t final)
230 {
231 	struct veriexec_fpops *ops;
232 
233 	KASSERT((init != NULL) && (update != NULL) && (final != NULL));
234 	KASSERT((hash_len != 0) && (ctx_size != 0));
235 	KASSERT(fp_type != NULL);
236 
237 	if (veriexec_fpops_lookup(fp_type) != NULL)
238 		return (EEXIST);
239 
240 	ops = kmem_alloc(sizeof(*ops), KM_SLEEP);
241 	ops->type = fp_type;
242 	ops->hash_len = hash_len;
243 	ops->context_size = ctx_size;
244 	ops->init = init;
245 	ops->update = update;
246 	ops->final = final;
247 
248 	LIST_INSERT_HEAD(&veriexec_fpops_list, ops, entries);
249 
250 	/*
251 	 * If we don't have space for any names, allocate enough for six
252 	 * which should be sufficient. (it's also enough for all algorithms
253 	 * we can support at the moment)
254 	 */
255 	if (veriexec_fp_names == NULL) {
256 		veriexec_name_max = 64;
257 		veriexec_fp_names = kmem_zalloc(veriexec_name_max, KM_SLEEP);
258 	}
259 
260 	/*
261 	 * If we're running out of space for storing supported algorithms,
262 	 * extend the buffer with space for four names.
263 	 */
264 	while (veriexec_name_max - (strlen(veriexec_fp_names) + 1) <
265 	    strlen(fp_type)) {
266 		char *newp;
267 		unsigned int new_max;
268 
269 		/* Add space for four algorithm names. */
270 		new_max = veriexec_name_max + 64;
271 		newp = kmem_zalloc(new_max, KM_SLEEP);
272 		strlcpy(newp, veriexec_fp_names, new_max);
273 		kmem_free(veriexec_fp_names, veriexec_name_max);
274 		veriexec_fp_names = newp;
275 		veriexec_name_max = new_max;
276 	}
277 
278 	if (*veriexec_fp_names != '\0')
279 		strlcat(veriexec_fp_names, " ", veriexec_name_max);
280 
281 	strlcat(veriexec_fp_names, fp_type, veriexec_name_max);
282 
283 	return (0);
284 }
285 
286 static void
287 veriexec_mountspecific_dtor(void *v)
288 {
289 	struct veriexec_table_entry *vte = v;
290 
291 	if (vte == NULL) {
292 		return;
293 	}
294 	sysctl_free(__UNCONST(vte->vte_node));
295 	veriexec_tablecount--;
296 	kmem_free(vte, sizeof(*vte));
297 }
298 
299 static int
300 veriexec_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
301     void *arg0, void *arg1, void *arg2, void *arg3)
302 {
303 	int result;
304 	enum kauth_system_req req;
305 
306 	if (action != KAUTH_SYSTEM_VERIEXEC)
307 		return KAUTH_RESULT_DEFER;
308 
309 	result = KAUTH_RESULT_DEFER;
310 	req = (enum kauth_system_req)(uintptr_t)arg0;
311 
312 	if (req == KAUTH_REQ_SYSTEM_VERIEXEC_MODIFY &&
313 	    veriexec_strict > VERIEXEC_LEARNING) {
314 		log(LOG_WARNING, "Veriexec: Strict mode, modifying "
315 		    "tables not permitted.\n");
316 
317 		result = KAUTH_RESULT_DENY;
318 	}
319 
320 	return result;
321 }
322 
323 /*
324  * Initialise Veriexec.
325  */
326 void
327 veriexec_init(void)
328 {
329 	int error;
330 
331 	/* Register a fileassoc for Veriexec. */
332 	error = fileassoc_register("veriexec",
333 	    (fileassoc_cleanup_cb_t)veriexec_file_free, &veriexec_hook);
334 	if (error)
335 		panic("Veriexec: Can't register fileassoc: error=%d", error);
336 
337 	/* Register listener to handle raw disk access. */
338 	if (kauth_listen_scope(KAUTH_SCOPE_DEVICE, veriexec_raw_cb, NULL) ==
339 	    NULL)
340 		panic("Veriexec: Can't listen on device scope");
341 
342 	error = mount_specific_key_create(&veriexec_mountspecific_key,
343 	    veriexec_mountspecific_dtor);
344 	if (error)
345 		panic("Veriexec: Can't create mountspecific key");
346 
347 	if (kauth_listen_scope(KAUTH_SCOPE_SYSTEM, veriexec_listener_cb,
348 	    NULL) == NULL)
349 		panic("Veriexec: Can't listen on system scope");
350 
351 	rw_init(&veriexec_op_lock);
352 
353 #define	FPOPS_ADD(a, b, c, d, e, f)			\
354 	veriexec_fpops_add(a, b, c,			\
355 	    __FPTRCAST(veriexec_fpop_init_t, d),	\
356 	    __FPTRCAST(veriexec_fpop_update_t, e),	\
357 	    __FPTRCAST(veriexec_fpop_final_t, f))
358 
359 #ifdef VERIFIED_EXEC_FP_SHA256
360 	FPOPS_ADD("SHA256", SHA256_DIGEST_LENGTH, sizeof(SHA256_CTX),
361 	    SHA256_Init, SHA256_Update, SHA256_Final);
362 #endif /* VERIFIED_EXEC_FP_SHA256 */
363 
364 #ifdef VERIFIED_EXEC_FP_SHA384
365 	FPOPS_ADD("SHA384", SHA384_DIGEST_LENGTH, sizeof(SHA384_CTX),
366 	    SHA384_Init, SHA384_Update, SHA384_Final);
367 #endif /* VERIFIED_EXEC_FP_SHA384 */
368 
369 #ifdef VERIFIED_EXEC_FP_SHA512
370 	FPOPS_ADD("SHA512", SHA512_DIGEST_LENGTH, sizeof(SHA512_CTX),
371 	    SHA512_Init, SHA512_Update, SHA512_Final);
372 #endif /* VERIFIED_EXEC_FP_SHA512 */
373 
374 #undef FPOPS_ADD
375 }
376 
377 static struct veriexec_fpops *
378 veriexec_fpops_lookup(const char *name)
379 {
380 	struct veriexec_fpops *ops;
381 
382 	if (name == NULL)
383 		return (NULL);
384 
385 	LIST_FOREACH(ops, &veriexec_fpops_list, entries) {
386 		if (strcasecmp(name, ops->type) == 0)
387 			return (ops);
388 	}
389 
390 	return (NULL);
391 }
392 
393 /*
394  * Calculate fingerprint. Information on hash length and routines used is
395  * extracted from veriexec_hash_list according to the hash type.
396  *
397  * NOTE: vfe is assumed to be locked for writing on entry.
398  */
399 static int
400 veriexec_fp_calc(struct lwp *l, struct vnode *vp, int file_lock_state,
401     struct veriexec_file_entry *vfe, u_char *fp)
402 {
403 	struct vattr va;
404 	void *ctx;
405 	u_char *buf;
406 	off_t offset, len;
407 	size_t resid;
408 	int error;
409 
410 	KASSERT(file_lock_state != VERIEXEC_LOCKED);
411 	KASSERT(file_lock_state != VERIEXEC_UNLOCKED);
412 
413 	if (file_lock_state == VERIEXEC_FILE_UNLOCKED)
414 		vn_lock(vp, LK_SHARED | LK_RETRY);
415 	error = VOP_GETATTR(vp, &va, l->l_cred);
416 	if (file_lock_state == VERIEXEC_FILE_UNLOCKED)
417 		VOP_UNLOCK(vp);
418 	if (error)
419 		return (error);
420 
421 	ctx = kmem_alloc(vfe->ops->context_size, KM_SLEEP);
422 	buf = kmem_alloc(PAGE_SIZE, KM_SLEEP);
423 
424 	(vfe->ops->init)(ctx);
425 
426 	len = 0;
427 	error = 0;
428 	for (offset = 0; offset < va.va_size; offset += PAGE_SIZE) {
429 		len = ((va.va_size - offset) < PAGE_SIZE) ?
430 		    (va.va_size - offset) : PAGE_SIZE;
431 
432 		error = vn_rdwr(UIO_READ, vp, buf, len, offset,
433 				UIO_SYSSPACE,
434 				((file_lock_state == VERIEXEC_FILE_LOCKED)?
435 				 IO_NODELOCKED : 0),
436 				l->l_cred, &resid, NULL);
437 
438 		if (error) {
439 			goto bad;
440 		}
441 
442 		(vfe->ops->update)(ctx, buf, (unsigned int) len);
443 
444 		if (len != PAGE_SIZE)
445 			break;
446 	}
447 
448 	(vfe->ops->final)(fp, ctx);
449 
450 bad:
451 	kmem_free(ctx, vfe->ops->context_size);
452 	kmem_free(buf, PAGE_SIZE);
453 
454 	return (error);
455 }
456 
457 /* Compare two fingerprints of the same type. */
458 static int
459 veriexec_fp_cmp(struct veriexec_fpops *ops, u_char *fp1, u_char *fp2)
460 {
461 	if (veriexec_verbose >= 2) {
462 		int i;
463 
464 		printf("comparing hashes...\n");
465 		printf("fp1: ");
466 		for (i = 0; i < ops->hash_len; i++) {
467 			printf("%02x", fp1[i]);
468 		}
469 		printf("\nfp2: ");
470 		for (i = 0; i < ops->hash_len; i++) {
471 			printf("%02x", fp2[i]);
472 		}
473 		printf("\n");
474 	}
475 
476 	return (memcmp(fp1, fp2, ops->hash_len));
477 }
478 
479 static int
480 veriexec_fp_status(struct lwp *l, struct vnode *vp, int file_lock_state,
481     struct veriexec_file_entry *vfe, u_char *status)
482 {
483 	size_t hash_len = vfe->ops->hash_len;
484 	u_char *digest;
485 	int error;
486 
487 	digest = kmem_zalloc(hash_len, KM_SLEEP);
488 
489 	error = veriexec_fp_calc(l, vp, file_lock_state, vfe, digest);
490 	if (error)
491 		goto out;
492 
493 	/* Compare fingerprint with loaded data. */
494 	if (veriexec_fp_cmp(vfe->ops, vfe->fp, digest) == 0)
495 		*status = FINGERPRINT_VALID;
496 	else
497 		*status = FINGERPRINT_NOMATCH;
498 
499 out:
500 	kmem_free(digest, hash_len);
501 	return error;
502 }
503 
504 
505 static struct veriexec_table_entry *
506 veriexec_table_lookup(struct mount *mp)
507 {
508 	/* XXX: From raidframe init */
509 	if (mp == NULL)
510 		return NULL;
511 
512 	return mount_getspecific(mp, veriexec_mountspecific_key);
513 }
514 
515 static struct veriexec_file_entry *
516 veriexec_get(struct vnode *vp)
517 {
518 	return (fileassoc_lookup(vp, veriexec_hook));
519 }
520 
521 bool
522 veriexec_lookup(struct vnode *vp)
523 {
524 	return (veriexec_get(vp) == NULL ? false : true);
525 }
526 
527 /*
528  * Routine for maintaining mostly consistent message formats in Veriexec.
529  */
530 static void
531 veriexec_file_report(struct veriexec_file_entry *vfe, const u_char *msg,
532     const u_char *filename, struct lwp *l, int f)
533 {
534 	if (vfe != NULL && vfe->filename != NULL)
535 		filename = vfe->filename;
536 	if (filename == NULL)
537 		return;
538 
539 	if (((f & REPORT_LOGMASK) >> 1) <= veriexec_verbose) {
540 		if (!(f & REPORT_ALARM) || (l == NULL))
541 			log(LOG_NOTICE, "Veriexec: %s [%s]\n", msg,
542 			    filename);
543 		else
544 			log(LOG_ALERT, "Veriexec: %s [%s, prog=%s pid=%u, "
545 			    "uid=%u, gid=%u]\n", msg, filename,
546 			    l->l_proc->p_comm, l->l_proc->p_pid,
547 			    kauth_cred_getuid(l->l_cred),
548 			    kauth_cred_getgid(l->l_cred));
549 	}
550 
551 	if (f & REPORT_PANIC)
552 		panic("Veriexec: Unrecoverable error.");
553 }
554 
555 /*
556  * Verify the fingerprint of the given file. If we're called directly from
557  * sys_execve(), 'flag' will be VERIEXEC_DIRECT. If we're called from
558  * exec_script(), 'flag' will be VERIEXEC_INDIRECT.  If we are called from
559  * vn_open(), 'flag' will be VERIEXEC_FILE.
560  *
561  * 'veriexec_op_lock' must be locked (and remains locked).
562  *
563  * NOTE: The veriexec file entry pointer (vfep) will be returned LOCKED
564  *       on no error.
565  */
566 static int
567 veriexec_file_verify(struct lwp *l, struct vnode *vp, const u_char *name,
568     int flag, int file_lock_state, struct veriexec_file_entry **vfep)
569 {
570 	struct veriexec_file_entry *vfe;
571 	int error = 0;
572 
573 	KASSERT(rw_lock_held(&veriexec_op_lock));
574 	KASSERT(file_lock_state != VERIEXEC_LOCKED);
575 	KASSERT(file_lock_state != VERIEXEC_UNLOCKED);
576 
577 #define VFE_NEEDS_EVAL(vfe) ((vfe->status == FINGERPRINT_NOTEVAL) || \
578 			     (vfe->type & VERIEXEC_UNTRUSTED))
579 
580 	if (vfep != NULL)
581 		*vfep = NULL;
582 
583 	if (vp->v_type != VREG)
584 		return (0);
585 
586 	/* Lookup veriexec table entry, save pointer if requested. */
587 	vfe = veriexec_get(vp);
588 	if (vfep != NULL)
589 		*vfep = vfe;
590 
591 	/* No entry in the veriexec tables. */
592 	if (vfe == NULL) {
593 		veriexec_file_report(NULL, "No entry.", name,
594 		    l, REPORT_VERBOSE);
595 
596 		/*
597 		 * Lockdown mode: Deny access to non-monitored files.
598 		 * IPS mode: Deny execution of non-monitored files.
599 		 */
600 		if ((veriexec_strict >= VERIEXEC_LOCKDOWN) ||
601 		    ((veriexec_strict >= VERIEXEC_IPS) &&
602 		     (flag != VERIEXEC_FILE)))
603 			return (EPERM);
604 
605 		return (0);
606 	}
607 
608 	/*
609 	 * Grab the lock for the entry, if we need to do an evaluation
610 	 * then the lock is a write lock, after we have the write
611 	 * lock, check if we really need it - some other thread may
612 	 * have already done the work for us.
613 	 */
614 	if (VFE_NEEDS_EVAL(vfe)) {
615 		rw_enter(&vfe->lock, RW_WRITER);
616 		if (!VFE_NEEDS_EVAL(vfe))
617 			rw_downgrade(&vfe->lock);
618 	} else
619 		rw_enter(&vfe->lock, RW_READER);
620 
621 	/* Evaluate fingerprint if needed. */
622 	if (VFE_NEEDS_EVAL(vfe)) {
623 		u_char status;
624 
625 		error = veriexec_fp_status(l, vp, file_lock_state, vfe, &status);
626 		if (error) {
627 			veriexec_file_report(vfe, "Fingerprint calculation error.",
628 			    name, NULL, REPORT_ALWAYS);
629 			rw_exit(&vfe->lock);
630 			return (error);
631 		}
632 		vfe->status = status;
633 		rw_downgrade(&vfe->lock);
634 	}
635 
636 	if (!(vfe->type & flag)) {
637 		veriexec_file_report(vfe, "Incorrect access type.", name, l,
638 		    REPORT_ALWAYS|REPORT_ALARM);
639 
640 		/* IPS mode: Enforce access type. */
641 		if (veriexec_strict >= VERIEXEC_IPS) {
642 			rw_exit(&vfe->lock);
643 			return (EPERM);
644 		}
645 	}
646 
647 	switch (vfe->status) {
648 	case FINGERPRINT_NOTEVAL:
649 		/* Should not happen. */
650 		rw_exit(&vfe->lock);
651 		veriexec_file_report(vfe, "Not-evaluated status "
652 		    "post evaluation; inconsistency detected.", name,
653 		    NULL, REPORT_ALWAYS|REPORT_PANIC);
654 		__builtin_unreachable();
655 		/* NOTREACHED */
656 
657 	case FINGERPRINT_VALID:
658 		/* Valid fingerprint. */
659 		veriexec_file_report(vfe, "Match.", name, NULL,
660 		    REPORT_VERBOSE);
661 
662 		break;
663 
664 	case FINGERPRINT_NOMATCH:
665 		/* Fingerprint mismatch. */
666 		veriexec_file_report(vfe, "Mismatch.", name,
667 		    NULL, REPORT_ALWAYS|REPORT_ALARM);
668 
669 		/* IDS mode: Deny access on fingerprint mismatch. */
670 		if (veriexec_strict >= VERIEXEC_IDS) {
671 			rw_exit(&vfe->lock);
672 			error = EPERM;
673 		}
674 
675 		break;
676 
677 	default:
678 		/* Should never happen. */
679 		rw_exit(&vfe->lock);
680 		veriexec_file_report(vfe, "Invalid status "
681 		    "post evaluation.", name, NULL, REPORT_ALWAYS|REPORT_PANIC);
682 		/* NOTREACHED */
683 	}
684 
685 	return (error);
686 }
687 
688 int
689 veriexec_verify(struct lwp *l, struct vnode *vp, const u_char *name, int flag,
690     bool *found)
691 {
692 	struct veriexec_file_entry *vfe;
693 	int r;
694 
695 	if (veriexec_bypass && (veriexec_strict == VERIEXEC_LEARNING))
696 		return 0;
697 
698 	rw_enter(&veriexec_op_lock, RW_READER);
699 	r = veriexec_file_verify(l, vp, name, flag, VERIEXEC_FILE_UNLOCKED,
700 	    &vfe);
701 	rw_exit(&veriexec_op_lock);
702 
703 	if ((r  == 0) && (vfe != NULL))
704 		rw_exit(&vfe->lock);
705 
706 	if (found != NULL)
707 		*found = (vfe != NULL) ? true : false;
708 
709 	return (r);
710 }
711 
712 /*
713  * Veriexec remove policy code.
714  */
715 int
716 veriexec_removechk(struct lwp *l, struct vnode *vp, const char *pathbuf)
717 {
718 	struct veriexec_file_entry *vfe;
719 	int error;
720 
721 	if (veriexec_bypass && (veriexec_strict == VERIEXEC_LEARNING))
722 		return 0;
723 
724 	rw_enter(&veriexec_op_lock, RW_READER);
725 	vfe = veriexec_get(vp);
726 	rw_exit(&veriexec_op_lock);
727 
728 	if (vfe == NULL) {
729 		/* Lockdown mode: Deny access to non-monitored files. */
730 		if (veriexec_strict >= VERIEXEC_LOCKDOWN)
731 			return (EPERM);
732 
733 		return (0);
734 	}
735 
736 	veriexec_file_report(vfe, "Remove request.", pathbuf, l,
737 	    REPORT_ALWAYS|REPORT_ALARM);
738 
739 	/* IDS mode: Deny removal of monitored files. */
740 	if (veriexec_strict >= VERIEXEC_IDS)
741 		error = EPERM;
742 	else
743 		error = veriexec_file_delete(l, vp);
744 
745 	return error;
746 }
747 
748 /*
749  * Veriexec rename policy.
750  *
751  * XXX: Once there's a way to hook after a successful rename, it would be
752  * XXX: nice to update vfe->filename to the new name if it's not NULL and
753  * XXX: the new name is absolute (ie., starts with a slash).
754  */
755 int
756 veriexec_renamechk(struct lwp *l, struct vnode *fromvp, const char *fromname,
757     struct vnode *tovp, const char *toname)
758 {
759 	struct veriexec_file_entry *fvfe = NULL, *tvfe = NULL;
760 
761 	if (veriexec_bypass && (veriexec_strict == VERIEXEC_LEARNING))
762 		return 0;
763 
764 	rw_enter(&veriexec_op_lock, RW_READER);
765 
766 	if (veriexec_strict >= VERIEXEC_LOCKDOWN) {
767 		log(LOG_ALERT, "Veriexec: Preventing rename of `%s' to "
768 		    "`%s', uid=%u, pid=%u: Lockdown mode.\n", fromname, toname,
769 		    kauth_cred_geteuid(l->l_cred), l->l_proc->p_pid);
770 		rw_exit(&veriexec_op_lock);
771 		return (EPERM);
772 	}
773 
774 	fvfe = veriexec_get(fromvp);
775 	if (tovp != NULL)
776 		tvfe = veriexec_get(tovp);
777 
778 	if ((fvfe == NULL) && (tvfe == NULL)) {
779 		/* None of them is monitored */
780 		rw_exit(&veriexec_op_lock);
781 		return 0;
782 	}
783 
784 	if (veriexec_strict >= VERIEXEC_IPS) {
785 		log(LOG_ALERT, "Veriexec: Preventing rename of `%s' "
786 		    "to `%s', uid=%u, pid=%u: IPS mode, %s "
787 		    "monitored.\n", fromname, toname,
788 		    kauth_cred_geteuid(l->l_cred),
789 		    l->l_proc->p_pid, (fvfe != NULL && tvfe != NULL) ?
790 		    "files" : "file");
791 		rw_exit(&veriexec_op_lock);
792 		return (EPERM);
793 	}
794 
795 	if (fvfe != NULL) {
796 		/*
797 		 * Monitored file is renamed; filename no longer relevant.
798 		 */
799 
800 		/*
801 		 * XXX: We could keep the buffer, and when (and if) updating the
802 		 * XXX: filename post-rename, re-allocate it only if it's not
803 		 * XXX: big enough for the new filename.
804 		 */
805 
806 		/* XXX: Get write lock on fvfe here? */
807 
808 		VERIEXEC_RW_UPGRADE(&veriexec_op_lock);
809 		/* once we have the op lock in write mode
810 		 * there should be no locks on any file
811 		 * entries so we can destroy the object.
812 		 */
813 
814 		if (fvfe->filename_len > 0)
815 			kmem_free(fvfe->filename, fvfe->filename_len);
816 
817 		fvfe->filename = NULL;
818 		fvfe->filename_len = 0;
819 
820 		rw_downgrade(&veriexec_op_lock);
821 	}
822 
823 	log(LOG_NOTICE, "Veriexec: %s file `%s' renamed to "
824 	    "%s file `%s', uid=%u, pid=%u.\n", (fvfe != NULL) ?
825 	    "Monitored" : "Non-monitored", fromname, (tvfe != NULL) ?
826 	    "monitored" : "non-monitored", toname,
827 	    kauth_cred_geteuid(l->l_cred), l->l_proc->p_pid);
828 
829 	rw_exit(&veriexec_op_lock);
830 
831 	if (tvfe != NULL) {
832 		/*
833 		 * Monitored file is overwritten. Remove the entry.
834 		 */
835 		(void)veriexec_file_delete(l, tovp);
836 	}
837 
838 	return (0);
839 }
840 
841 static void
842 veriexec_file_free(struct veriexec_file_entry *vfe)
843 {
844 	if (vfe != NULL) {
845 		if (vfe->fp != NULL)
846 			kmem_free(vfe->fp, vfe->ops->hash_len);
847 		if (vfe->filename != NULL)
848 			kmem_free(vfe->filename, vfe->filename_len);
849 		rw_destroy(&vfe->lock);
850 		kmem_free(vfe, sizeof(*vfe));
851 	}
852 }
853 
854 static void
855 veriexec_file_purge(struct veriexec_file_entry *vfe, int have_lock)
856 {
857 	if (vfe == NULL)
858 		return;
859 
860 	if (have_lock == VERIEXEC_UNLOCKED)
861 		rw_enter(&vfe->lock, RW_WRITER);
862 	else
863 		VERIEXEC_RW_UPGRADE(&vfe->lock);
864 
865 	vfe->status = FINGERPRINT_NOTEVAL;
866 	if (have_lock == VERIEXEC_UNLOCKED)
867 		rw_exit(&vfe->lock);
868 	else
869 		rw_downgrade(&vfe->lock);
870 }
871 
872 static void
873 veriexec_file_purge_cb(struct veriexec_file_entry *vfe, void *cookie)
874 {
875 	veriexec_file_purge(vfe, VERIEXEC_UNLOCKED);
876 }
877 
878 /*
879  * Invalidate a Veriexec file entry.
880  * XXX: This should be updated when per-page fingerprints are added.
881  */
882 void
883 veriexec_purge(struct vnode *vp)
884 {
885 	rw_enter(&veriexec_op_lock, RW_READER);
886 	veriexec_file_purge(veriexec_get(vp), VERIEXEC_UNLOCKED);
887 	rw_exit(&veriexec_op_lock);
888 }
889 
890 /*
891  * Enforce raw disk access policy.
892  *
893  * IDS mode: Invalidate fingerprints on a mount if it's opened for writing.
894  * IPS mode: Don't allow raw writing to disks we monitor.
895  * Lockdown mode: Don't allow raw writing to all disks.
896  *
897  * XXX: This is bogus. There's an obvious race condition between the time
898  * XXX: the disk is open for writing, in which an attacker can access a
899  * XXX: monitored file to get its signature cached again, and when the raw
900  * XXX: file is overwritten on disk.
901  * XXX:
902  * XXX: To solve this, we need something like the following:
903  * XXX:		open raw disk:
904  * XXX:		  - raise refcount,
905  * XXX:		  - invalidate fingerprints,
906  * XXX:		  - mark all entries for that disk with "no cache" flag
907  * XXX:
908  * XXX:		veriexec_verify:
909  * XXX:		  - if "no cache", don't cache evaluation result
910  * XXX:
911  * XXX:		close raw disk:
912  * XXX:		  - lower refcount,
913  * XXX:		  - if refcount == 0, remove "no cache" flag from all entries
914  */
915 static int
916 veriexec_raw_cb(kauth_cred_t cred, kauth_action_t action, void *cookie,
917     void *arg0, void *arg1, void *arg2, void *arg3)
918 {
919 	int result;
920 	enum kauth_device_req req;
921 	struct veriexec_table_entry *vte;
922 
923 	result = KAUTH_RESULT_DENY;
924 	req = (enum kauth_device_req)(uintptr_t)arg0;
925 
926 	switch (action) {
927 	case KAUTH_DEVICE_RAWIO_SPEC: {
928 		struct vnode *vp, *bvp;
929 		int error;
930 
931 		if (req == KAUTH_REQ_DEVICE_RAWIO_SPEC_READ) {
932 			result = KAUTH_RESULT_DEFER;
933 			break;
934 		}
935 
936 		vp = arg1;
937 		KASSERT(vp != NULL);
938 
939 		/* Handle /dev/mem and /dev/kmem. */
940 		if (iskmemvp(vp)) {
941 			if (veriexec_strict < VERIEXEC_IPS)
942 				result = KAUTH_RESULT_DEFER;
943 
944 			break;
945 		}
946 
947 		error = rawdev_mounted(vp, &bvp);
948 		if (error == EINVAL) {
949 			result = KAUTH_RESULT_DEFER;
950 			break;
951 		}
952 
953 		/*
954 		 * XXX: See vfs_mountedon() comment in rawdev_mounted().
955 		 */
956 		vte = veriexec_table_lookup(bvp->v_mount);
957 		if (vte == NULL) {
958 			result = KAUTH_RESULT_DEFER;
959 			break;
960 		}
961 
962 		switch (veriexec_strict) {
963 		case VERIEXEC_LEARNING:
964 		case VERIEXEC_IDS:
965 			result = KAUTH_RESULT_DEFER;
966 
967 			rw_enter(&veriexec_op_lock, RW_WRITER);
968 			fileassoc_table_run(bvp->v_mount, veriexec_hook,
969 			    (fileassoc_cb_t)veriexec_file_purge_cb, NULL);
970 			rw_exit(&veriexec_op_lock);
971 
972 			break;
973 		case VERIEXEC_IPS:
974 			result = KAUTH_RESULT_DENY;
975 			break;
976 		case VERIEXEC_LOCKDOWN:
977 			result = KAUTH_RESULT_DENY;
978 			break;
979 		}
980 
981 		break;
982 		}
983 
984 	case KAUTH_DEVICE_RAWIO_PASSTHRU:
985 		/* XXX What can we do here? */
986 		if (veriexec_strict < VERIEXEC_IPS)
987 			result = KAUTH_RESULT_DEFER;
988 
989 		break;
990 
991 	default:
992 		result = KAUTH_RESULT_DEFER;
993 		break;
994 	}
995 
996 	return (result);
997 }
998 
999 /*
1000  * Create a new Veriexec table.
1001  */
1002 static struct veriexec_table_entry *
1003 veriexec_table_add(struct lwp *l, struct mount *mp)
1004 {
1005 	struct veriexec_table_entry *vte;
1006 	u_char buf[16];
1007 
1008 	vte = kmem_zalloc(sizeof(*vte), KM_SLEEP);
1009 	mount_setspecific(mp, veriexec_mountspecific_key, vte);
1010 
1011 	snprintf(buf, sizeof(buf), "table%u", veriexec_tablecount++);
1012 	sysctl_createv(NULL, 0, &veriexec_count_node, &vte->vte_node,
1013 		       0, CTLTYPE_NODE, buf, NULL, NULL, 0, NULL,
1014 		       0, CTL_CREATE, CTL_EOL);
1015 
1016 	sysctl_createv(NULL, 0, &vte->vte_node, NULL,
1017 		       CTLFLAG_READONLY, CTLTYPE_STRING, "mntpt",
1018 		       NULL, NULL, 0, mp->mnt_stat.f_mntonname,
1019 		       0, CTL_CREATE, CTL_EOL);
1020 	sysctl_createv(NULL, 0, &vte->vte_node, NULL,
1021 		       CTLFLAG_READONLY, CTLTYPE_STRING, "fstype",
1022 		       NULL, NULL, 0, mp->mnt_stat.f_fstypename,
1023 		       0, CTL_CREATE, CTL_EOL);
1024 	sysctl_createv(NULL, 0, &vte->vte_node, NULL,
1025 		       CTLFLAG_READONLY, CTLTYPE_QUAD, "nentries",
1026 		       NULL, NULL, 0, &vte->vte_count, 0, CTL_CREATE, CTL_EOL);
1027 
1028 	return (vte);
1029 }
1030 
1031 /*
1032  * Add a file to be monitored by Veriexec.
1033  *
1034  * Expected elements in dict:
1035  *     file, fp, fp-type, entry-type, keep-filename, eval-on-load.
1036  */
1037 int
1038 veriexec_file_add(struct lwp *l, prop_dictionary_t dict)
1039 {
1040 	struct veriexec_table_entry *vte;
1041 	struct veriexec_file_entry *vfe = NULL;
1042 	struct veriexec_file_entry *ovfe;
1043 	struct vnode *vp;
1044 	const char *file, *fp_type;
1045 	int error;
1046 	bool ignore_dup = false;
1047 
1048 	if (!prop_dictionary_get_string(dict, "file", &file))
1049 		return (EINVAL);
1050 
1051 	error = namei_simple_kernel(file, NSM_FOLLOW_NOEMULROOT, &vp);
1052 	if (error)
1053 		return (error);
1054 
1055 	/* Add only regular files. */
1056 	if (vp->v_type != VREG) {
1057 		log(LOG_ERR, "Veriexec: Not adding `%s': Not a regular file.\n",
1058 		    file);
1059 		error = EBADF;
1060 		goto out;
1061 	}
1062 
1063 	vfe = kmem_zalloc(sizeof(*vfe), KM_SLEEP);
1064 	rw_init(&vfe->lock);
1065 
1066 	/* Lookup fingerprint hashing algorithm. */
1067 	fp_type = prop_string_value(prop_dictionary_get(dict, "fp-type"));
1068 	if ((vfe->ops = veriexec_fpops_lookup(fp_type)) == NULL) {
1069 		log(LOG_ERR, "Veriexec: Invalid or unknown fingerprint type "
1070 		    "`%s' for file `%s'.\n", fp_type, file);
1071 		error = EOPNOTSUPP;
1072 		goto out;
1073 	}
1074 
1075 	if (prop_data_size(prop_dictionary_get(dict, "fp")) !=
1076 	    vfe->ops->hash_len) {
1077 		log(LOG_ERR, "Veriexec: Bad fingerprint length for `%s'.\n",
1078 		    file);
1079 		error = EINVAL;
1080 		goto out;
1081 	}
1082 
1083 	vfe->fp = kmem_alloc(vfe->ops->hash_len, KM_SLEEP);
1084 	memcpy(vfe->fp, prop_data_value(prop_dictionary_get(dict, "fp")),
1085 	    vfe->ops->hash_len);
1086 
1087 	rw_enter(&veriexec_op_lock, RW_WRITER);
1088 
1089 	/* Continue entry initialization. */
1090 	if (prop_dictionary_get_uint8(dict, "entry-type", &vfe->type) == FALSE)
1091 		vfe->type = 0;
1092 	else {
1093 		uint8_t extra_flags;
1094 
1095 		extra_flags = vfe->type & ~(VERIEXEC_DIRECT |
1096 		    VERIEXEC_INDIRECT | VERIEXEC_FILE | VERIEXEC_UNTRUSTED);
1097 		if (extra_flags) {
1098 			log(LOG_NOTICE, "Veriexec: Contaminated flags `0x%x' "
1099 			    "for `%s', skipping.\n", extra_flags, file);
1100 			error = EINVAL;
1101 			goto unlock_out;
1102 		}
1103 	}
1104 	if (!(vfe->type & (VERIEXEC_DIRECT | VERIEXEC_INDIRECT |
1105 	    VERIEXEC_FILE)))
1106 		vfe->type |= VERIEXEC_DIRECT;
1107 
1108 	vfe->status = FINGERPRINT_NOTEVAL;
1109 	if (prop_bool_true(prop_dictionary_get(dict, "keep-filename"))) {
1110 		vfe->filename = kmem_strdupsize(file, &vfe->filename_len,
1111 		    KM_SLEEP);
1112 	} else
1113 		vfe->filename = NULL;
1114 
1115 	if (prop_bool_true(prop_dictionary_get(dict, "eval-on-load")) ||
1116 	    (vfe->type & VERIEXEC_UNTRUSTED)) {
1117 		u_char status;
1118 
1119 		error = veriexec_fp_status(l, vp, VERIEXEC_FILE_UNLOCKED,
1120 		    vfe, &status);
1121 		if (error)
1122 			goto unlock_out;
1123 		vfe->status = status;
1124 	}
1125 
1126 	/*
1127 	 * If we already have an entry for this file, and it matches
1128 	 * the new entry exactly (except for the filename, which may
1129 	 * hard-linked!), we just ignore the new entry.  If the new
1130 	 * entry differs, report the error.
1131 	 */
1132 	if ((ovfe = veriexec_get(vp)) != NULL) {
1133 		error = EEXIST;
1134 		if (vfe->type == ovfe->type &&
1135 		    vfe->status == ovfe->status &&
1136 		    vfe->ops == ovfe->ops &&
1137 		    memcmp(vfe->fp, ovfe->fp, vfe->ops->hash_len) == 0)
1138 			ignore_dup = true;
1139 		goto unlock_out;
1140 	}
1141 
1142 	vte = veriexec_table_lookup(vp->v_mount);
1143 	if (vte == NULL)
1144 		vte = veriexec_table_add(l, vp->v_mount);
1145 
1146 	/* XXX if we bail below this, we might want to gc newly created vtes. */
1147 
1148 	error = fileassoc_add(vp, veriexec_hook, vfe);
1149 	if (error)
1150 		goto unlock_out;
1151 
1152 	vte->vte_count++;
1153 
1154 	veriexec_file_report(NULL, "New entry.", file, NULL, REPORT_DEBUG);
1155 	veriexec_bypass = 0;
1156 
1157   unlock_out:
1158 	rw_exit(&veriexec_op_lock);
1159 
1160   out:
1161 	vrele(vp);
1162 	if (error)
1163 		veriexec_file_free(vfe);
1164 
1165 	if (ignore_dup && error == EEXIST)
1166 		error = 0;
1167 
1168 	return (error);
1169 }
1170 
1171 int
1172 veriexec_table_delete(struct lwp *l, struct mount *mp)
1173 {
1174 	struct veriexec_table_entry *vte;
1175 
1176 	vte = veriexec_table_lookup(mp);
1177 	if (vte == NULL)
1178 		return (ENOENT);
1179 
1180 	veriexec_mountspecific_dtor(vte);
1181 	mount_setspecific(mp, veriexec_mountspecific_key, NULL);
1182 
1183 	return (fileassoc_table_clear(mp, veriexec_hook));
1184 }
1185 
1186 int
1187 veriexec_file_delete(struct lwp *l, struct vnode *vp)
1188 {
1189 	struct veriexec_table_entry *vte;
1190 	int error;
1191 
1192 	vte = veriexec_table_lookup(vp->v_mount);
1193 	if (vte == NULL)
1194 		return (ENOENT);
1195 
1196 	rw_enter(&veriexec_op_lock, RW_WRITER);
1197 	error = fileassoc_clear(vp, veriexec_hook);
1198 	rw_exit(&veriexec_op_lock);
1199 	if (!error) {
1200 		KASSERT(vte->vte_count > 0);
1201 		vte->vte_count--;
1202 	}
1203 
1204 	return (error);
1205 }
1206 
1207 /*
1208  * Convert Veriexec entry data to a dictionary readable by userland tools.
1209  */
1210 static void
1211 veriexec_file_convert(struct veriexec_file_entry *vfe, prop_dictionary_t rdict)
1212 {
1213 	if (vfe->filename)
1214 		prop_dictionary_set(rdict, "file",
1215 		    prop_string_create_copy(vfe->filename));
1216 	prop_dictionary_set_uint8(rdict, "entry-type", vfe->type);
1217 	prop_dictionary_set_uint8(rdict, "status", vfe->status);
1218 	prop_dictionary_set(rdict, "fp-type",
1219 	    prop_string_create_copy(vfe->ops->type));
1220 	prop_dictionary_set(rdict, "fp",
1221 	    prop_data_create_copy(vfe->fp, vfe->ops->hash_len));
1222 }
1223 
1224 int
1225 veriexec_convert(struct vnode *vp, prop_dictionary_t rdict)
1226 {
1227 	struct veriexec_file_entry *vfe;
1228 
1229 	rw_enter(&veriexec_op_lock, RW_READER);
1230 
1231 	vfe = veriexec_get(vp);
1232 	if (vfe == NULL) {
1233 		rw_exit(&veriexec_op_lock);
1234 		return (ENOENT);
1235 	}
1236 
1237 	rw_enter(&vfe->lock, RW_READER);
1238 	veriexec_file_convert(vfe, rdict);
1239 	rw_exit(&vfe->lock);
1240 
1241 	rw_exit(&veriexec_op_lock);
1242 	return (0);
1243 }
1244 
1245 int
1246 veriexec_unmountchk(struct mount *mp)
1247 {
1248 	int error;
1249 
1250 	if ((veriexec_bypass && (veriexec_strict == VERIEXEC_LEARNING))
1251 	    || doing_shutdown)
1252 		return (0);
1253 
1254 	rw_enter(&veriexec_op_lock, RW_READER);
1255 
1256 	switch (veriexec_strict) {
1257 	case VERIEXEC_LEARNING:
1258 		error = 0;
1259 		break;
1260 
1261 	case VERIEXEC_IDS:
1262 		if (veriexec_table_lookup(mp) != NULL) {
1263 			log(LOG_INFO, "Veriexec: IDS mode, allowing unmount "
1264 			    "of \"%s\".\n", mp->mnt_stat.f_mntonname);
1265 		}
1266 
1267 		error = 0;
1268 		break;
1269 
1270 	case VERIEXEC_IPS: {
1271 		struct veriexec_table_entry *vte;
1272 
1273 		vte = veriexec_table_lookup(mp);
1274 		if ((vte != NULL) && (vte->vte_count > 0)) {
1275 			log(LOG_ALERT, "Veriexec: IPS mode, preventing"
1276 			    " unmount of \"%s\" with monitored files.\n",
1277 			    mp->mnt_stat.f_mntonname);
1278 
1279 			error = EPERM;
1280 		} else
1281 			error = 0;
1282 		break;
1283 		}
1284 
1285 	case VERIEXEC_LOCKDOWN:
1286 	default:
1287 		log(LOG_ALERT, "Veriexec: Lockdown mode, preventing unmount "
1288 		    "of \"%s\".\n", mp->mnt_stat.f_mntonname);
1289 		error = EPERM;
1290 		break;
1291 	}
1292 
1293 	rw_exit(&veriexec_op_lock);
1294 	return (error);
1295 }
1296 
1297 int
1298 veriexec_openchk(struct lwp *l, struct vnode *vp, const char *path, int fmode)
1299 {
1300 	struct veriexec_file_entry *vfe = NULL;
1301 	int error = 0;
1302 
1303 	if (veriexec_bypass && (veriexec_strict == VERIEXEC_LEARNING))
1304 		return 0;
1305 
1306 	if (vp == NULL) {
1307 		/* If no creation requested, let this fail normally. */
1308 		if (!(fmode & O_CREAT))
1309 			goto out;
1310 
1311 		/* Lockdown mode: Prevent creation of new files. */
1312 		if (veriexec_strict >= VERIEXEC_LOCKDOWN) {
1313 			log(LOG_ALERT, "Veriexec: Preventing new file "
1314 			    "creation in `%s'.\n", path);
1315 			error = EPERM;
1316 		}
1317 
1318 		goto out;
1319 	}
1320 
1321 	rw_enter(&veriexec_op_lock, RW_READER);
1322 	error = veriexec_file_verify(l, vp, path, VERIEXEC_FILE,
1323 				     VERIEXEC_FILE_LOCKED, &vfe);
1324 
1325 	if (error) {
1326 		rw_exit(&veriexec_op_lock);
1327 		goto out;
1328 	}
1329 
1330 	if ((vfe != NULL) && ((fmode & FWRITE) || (fmode & O_TRUNC))) {
1331 		veriexec_file_report(vfe, "Write access request.", path, l,
1332 		    REPORT_ALWAYS | REPORT_ALARM);
1333 
1334 		/* IPS mode: Deny write access to monitored files. */
1335 		if (veriexec_strict >= VERIEXEC_IPS)
1336 			error = EPERM;
1337 		else
1338 			veriexec_file_purge(vfe, VERIEXEC_LOCKED);
1339 	}
1340 
1341 	if (vfe != NULL)
1342 		rw_exit(&vfe->lock);
1343 
1344 	rw_exit(&veriexec_op_lock);
1345  out:
1346 	return (error);
1347 }
1348 
1349 static void
1350 veriexec_file_dump(struct veriexec_file_entry *vfe, prop_array_t entries)
1351 {
1352 	prop_dictionary_t entry;
1353 
1354 	/* If we don't have a filename, this is meaningless. */
1355 	if (vfe->filename == NULL)
1356 		return;
1357 
1358 	entry = prop_dictionary_create();
1359 
1360 	veriexec_file_convert(vfe, entry);
1361 
1362 	prop_array_add(entries, entry);
1363 }
1364 
1365 int
1366 veriexec_dump(struct lwp *l, prop_array_t rarray)
1367 {
1368 	mount_iterator_t *iter;
1369 	struct mount *mp;
1370 
1371 	mountlist_iterator_init(&iter);
1372 	while ((mp = mountlist_iterator_next(iter)) != NULL) {
1373 		fileassoc_table_run(mp, veriexec_hook,
1374 		    (fileassoc_cb_t)veriexec_file_dump, rarray);
1375 	}
1376 	mountlist_iterator_destroy(iter);
1377 
1378 	return (0);
1379 }
1380 
1381 int
1382 veriexec_flush(struct lwp *l)
1383 {
1384 	mount_iterator_t *iter;
1385 	struct mount *mp;
1386 	int error = 0;
1387 
1388 	mountlist_iterator_init(&iter);
1389 	while ((mp = mountlist_iterator_next(iter)) != NULL) {
1390 		int lerror;
1391 
1392 		lerror = veriexec_table_delete(l, mp);
1393 		if (lerror && lerror != ENOENT)
1394 			error = lerror;
1395 	}
1396 	mountlist_iterator_destroy(iter);
1397 
1398 	return (error);
1399 }
1400