xref: /titanic_41/usr/src/cmd/svc/common/manifest_hash.c (revision a31148363f598def767ac48c5d82e1572e44b935)
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 2010 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 
27 #include <sys/stat.h>
28 #include <sys/types.h>
29 
30 #include <assert.h>
31 #include <ctype.h>
32 #include <errno.h>
33 #include <fcntl.h>
34 #include <libintl.h>
35 #include <libscf.h>
36 #include <libuutil.h>
37 #include <limits.h>
38 #include <md5.h>
39 #include <pthread.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <strings.h>
44 #include <unistd.h>
45 
46 #include <manifest_hash.h>
47 
48 /*
49  * Translate a file name to property name.  Return an allocated string or NULL
50  * if realpath() fails. If deathrow is true, realpath() is skipped. This
51  * allows to return the property name even if the file doesn't exist.
52  */
53 char *
54 mhash_filename_to_propname(const char *in, boolean_t deathrow)
55 {
56 	char *out, *cp, *base;
57 	size_t len, piece_len;
58 
59 	out = uu_zalloc(PATH_MAX + 1);
60 	if (deathrow) {
61 		/* used only for service deathrow handling */
62 		if (strlcpy(out, in, PATH_MAX + 1) >= (PATH_MAX + 1)) {
63 			uu_free(out);
64 			return (NULL);
65 		}
66 	} else {
67 		if (realpath(in, out) == NULL) {
68 			uu_free(out);
69 			return (NULL);
70 		}
71 	}
72 
73 	base = getenv("PKG_INSTALL_ROOT");
74 
75 	/*
76 	 * We copy-shift over the basedir and the leading slash, since it's
77 	 * not relevant to when we boot with this repository.
78 	 */
79 
80 	cp = out + ((base != NULL)? strlen(base) : 0);
81 	if (*cp == '/')
82 		cp++;
83 	(void) memmove(out, cp, strlen(cp) + 1);
84 
85 	len = strlen(out);
86 	if (len > scf_limit(SCF_LIMIT_MAX_NAME_LENGTH)) {
87 		/* Use the first half and the second half. */
88 		piece_len = (scf_limit(SCF_LIMIT_MAX_NAME_LENGTH) - 3) / 2;
89 
90 		(void) strncpy(out + piece_len, "__", 2);
91 
92 		(void) memmove(out + piece_len + 2, out + (len - piece_len),
93 		    piece_len + 1);
94 	}
95 
96 	/*
97 	 * Translate non-property characters to '_', first making sure that
98 	 * we don't begin with '_'.
99 	 */
100 
101 	if (!isalpha(*out))
102 		*out = 'A';
103 
104 	for (cp = out + 1; *cp != '\0'; ++cp) {
105 		if (!(isalnum(*cp) || *cp == '_' || *cp == '-'))
106 			*cp = '_';
107 	}
108 
109 	return (out);
110 }
111 
112 int
113 mhash_retrieve_entry(scf_handle_t *hndl, const char *name, uchar_t *hash,
114     apply_action_t *action)
115 {
116 	scf_scope_t *scope;
117 	scf_service_t *svc;
118 	scf_propertygroup_t *pg;
119 	scf_property_t *prop;
120 	scf_value_t *val;
121 	scf_error_t err;
122 	ssize_t szret;
123 	int result = 0;
124 
125 	if (action)
126 		*action = APPLY_NONE;
127 
128 	/*
129 	 * In this implementation the hash for name is the opaque value of
130 	 * svc:/MHASH_SVC/:properties/name/MHASH_PROP
131 	 */
132 
133 	if ((scope = scf_scope_create(hndl)) == NULL ||
134 	    (svc = scf_service_create(hndl)) == NULL ||
135 	    (pg = scf_pg_create(hndl)) == NULL ||
136 	    (prop = scf_property_create(hndl)) == NULL ||
137 	    (val = scf_value_create(hndl)) == NULL) {
138 		result = -1;
139 		goto out;
140 	}
141 
142 	if (scf_handle_get_local_scope(hndl, scope) < 0) {
143 		result = -1;
144 		goto out;
145 	}
146 
147 	if (scf_scope_get_service(scope, MHASH_SVC, svc) < 0) {
148 		result = -1;
149 		goto out;
150 	}
151 
152 	if (scf_service_get_pg(svc, name, pg) != SCF_SUCCESS) {
153 		result = -1;
154 		goto out;
155 	}
156 
157 	if (scf_pg_get_property(pg, MHASH_PROP, prop) != SCF_SUCCESS) {
158 		result = -1;
159 		goto out;
160 	}
161 
162 	if (scf_property_get_value(prop, val) != SCF_SUCCESS) {
163 		result = -1;
164 		goto out;
165 	}
166 
167 	szret = scf_value_get_opaque(val, hash, MHASH_SIZE);
168 	if (szret < 0) {
169 		result = -1;
170 		goto out;
171 	}
172 
173 	/*
174 	 * Make sure that the old hash is returned with
175 	 * remainder of the bytes zeroed.
176 	 */
177 	if (szret == MHASH_SIZE_OLD) {
178 		(void) memset(hash + MHASH_SIZE_OLD, 0,
179 		    MHASH_SIZE - MHASH_SIZE_OLD);
180 	} else if (szret != MHASH_SIZE) {
181 		scf_value_destroy(val);
182 		result = -1;
183 		goto out;
184 	}
185 
186 	/*
187 	 * If caller has requested the apply_last property, read the
188 	 * property if it exists.
189 	 */
190 	if (action != NULL) {
191 		uint8_t apply_value;
192 
193 		if (scf_pg_get_property(pg, MHASH_APPLY_PROP, prop) !=
194 		    SCF_SUCCESS) {
195 			err = scf_error();
196 			if ((err != SCF_ERROR_DELETED) &&
197 			    (err != SCF_ERROR_NOT_FOUND)) {
198 				result = -1;
199 			}
200 			goto out;
201 		}
202 		if (scf_property_get_value(prop, val) != SCF_SUCCESS) {
203 			err = scf_error();
204 			if ((err != SCF_ERROR_DELETED) &&
205 			    (err != SCF_ERROR_NOT_FOUND)) {
206 				result = -1;
207 			}
208 			goto out;
209 		}
210 		if (scf_value_get_boolean(val, &apply_value) != SCF_SUCCESS) {
211 			result = -1;
212 			goto out;
213 		}
214 		if (apply_value)
215 			*action = APPLY_LATE;
216 	}
217 
218 out:
219 	(void) scf_value_destroy(val);
220 	scf_property_destroy(prop);
221 	scf_pg_destroy(pg);
222 	scf_service_destroy(svc);
223 	scf_scope_destroy(scope);
224 
225 	return (result);
226 }
227 
228 int
229 mhash_store_entry(scf_handle_t *hndl, const char *name, const char *fname,
230     uchar_t *hash, apply_action_t apply_late, char **errstr)
231 {
232 	scf_scope_t *scope = NULL;
233 	scf_service_t *svc = NULL;
234 	scf_propertygroup_t *pg = NULL;
235 	scf_property_t *prop = NULL;
236 	scf_value_t *aval = NULL;
237 	scf_value_t *val = NULL;
238 	scf_value_t *fval = NULL;
239 	scf_transaction_t *tx = NULL;
240 	scf_transaction_entry_t *ae = NULL;
241 	scf_transaction_entry_t *e = NULL;
242 	scf_transaction_entry_t *fe = NULL;
243 	scf_error_t err;
244 	int ret, result = 0;
245 
246 	int i;
247 
248 	if ((scope = scf_scope_create(hndl)) == NULL ||
249 	    (svc = scf_service_create(hndl)) == NULL ||
250 	    (pg = scf_pg_create(hndl)) == NULL ||
251 	    (prop = scf_property_create(hndl)) == NULL) {
252 		if (errstr != NULL)
253 			*errstr = gettext("Could not create scf objects");
254 		result = -1;
255 		goto out;
256 	}
257 
258 	if (scf_handle_get_local_scope(hndl, scope) != SCF_SUCCESS) {
259 		if (errstr != NULL)
260 			*errstr = gettext("Could not get local scope");
261 		result = -1;
262 		goto out;
263 	}
264 
265 	for (i = 0; i < 5; ++i) {
266 
267 		if (scf_scope_get_service(scope, MHASH_SVC, svc) ==
268 		    SCF_SUCCESS)
269 			break;
270 
271 		if (scf_error() != SCF_ERROR_NOT_FOUND) {
272 			if (errstr != NULL)
273 				*errstr = gettext("Could not get manifest hash "
274 				    "service");
275 			result = -1;
276 			goto out;
277 		}
278 
279 		if (scf_scope_add_service(scope, MHASH_SVC, svc) ==
280 		    SCF_SUCCESS)
281 			break;
282 
283 		err = scf_error();
284 
285 		if (err == SCF_ERROR_EXISTS)
286 			/* Try again. */
287 			continue;
288 		else if (err == SCF_ERROR_PERMISSION_DENIED) {
289 			if (errstr != NULL)
290 				*errstr = gettext("Could not store file hash: "
291 				    "permission denied.\n");
292 			result = -1;
293 			goto out;
294 		}
295 
296 		if (errstr != NULL)
297 			*errstr = gettext("Could not add manifest hash "
298 			    "service");
299 		result = -1;
300 		goto out;
301 	}
302 
303 	if (i == 5) {
304 		if (errstr != NULL)
305 			*errstr = gettext("Could not store file hash: "
306 			    "service addition contention.\n");
307 		result = -1;
308 		goto out;
309 	}
310 
311 	for (i = 0; i < 5; ++i) {
312 		if (scf_service_get_pg(svc, name, pg) == SCF_SUCCESS)
313 			break;
314 
315 		if (scf_error() != SCF_ERROR_NOT_FOUND) {
316 			if (errstr != NULL)
317 				*errstr = gettext("Could not get service's "
318 				    "hash record)");
319 			result = -1;
320 			goto out;
321 		}
322 
323 		if (scf_service_add_pg(svc, name, MHASH_PG_TYPE,
324 		    MHASH_PG_FLAGS, pg) == SCF_SUCCESS)
325 			break;
326 
327 		err = scf_error();
328 
329 		if (err == SCF_ERROR_EXISTS)
330 			/* Try again. */
331 			continue;
332 		else if (err == SCF_ERROR_PERMISSION_DENIED) {
333 			if (errstr != NULL)
334 				*errstr = gettext("Could not store file hash: "
335 				    "permission denied.\n");
336 			result = -1;
337 			goto out;
338 		}
339 
340 		if (errstr != NULL)
341 			*errstr = gettext("Could not store file hash");
342 		result = -1;
343 		goto out;
344 	}
345 	if (i == 5) {
346 		if (errstr != NULL)
347 			*errstr = gettext("Could not store file hash: "
348 			    "property group addition contention.\n");
349 		result = -1;
350 		goto out;
351 	}
352 
353 	if ((e = scf_entry_create(hndl)) == NULL ||
354 	    (val = scf_value_create(hndl)) == NULL ||
355 	    (fe = scf_entry_create(hndl)) == NULL ||
356 	    (fval = scf_value_create(hndl)) == NULL ||
357 	    (ae = scf_entry_create(hndl)) == NULL ||
358 	    (aval = scf_value_create(hndl)) == NULL) {
359 		if (errstr != NULL)
360 			*errstr = gettext("Could not store file hash: "
361 			    "permission denied.\n");
362 		result = -1;
363 		goto out;
364 	}
365 
366 	ret = scf_value_set_opaque(val, hash, MHASH_SIZE);
367 	assert(ret == SCF_SUCCESS);
368 	ret = scf_value_set_astring(fval, fname);
369 	assert(ret == SCF_SUCCESS);
370 	if (apply_late == APPLY_LATE) {
371 		scf_value_set_boolean(aval, 1);
372 	}
373 
374 	tx = scf_transaction_create(hndl);
375 	if (tx == NULL) {
376 		if (errstr != NULL)
377 			*errstr = gettext("Could not create transaction");
378 		result = -1;
379 		goto out;
380 	}
381 
382 	do {
383 		if (scf_pg_update(pg) == -1) {
384 			if (errstr != NULL)
385 				*errstr = gettext("Could not update hash "
386 				    "entry");
387 			result = -1;
388 			goto out;
389 		}
390 		if (scf_transaction_start(tx, pg) != SCF_SUCCESS) {
391 			if (scf_error() != SCF_ERROR_PERMISSION_DENIED) {
392 				if (errstr != NULL)
393 					*errstr = gettext("Could not start "
394 					    "hash transaction.\n");
395 				result = -1;
396 				goto out;
397 			}
398 
399 			if (errstr != NULL)
400 				*errstr = gettext("Could not store file hash: "
401 				    "permission denied.\n");
402 			result = -1;
403 
404 			scf_transaction_destroy(tx);
405 			(void) scf_entry_destroy(e);
406 			goto out;
407 		}
408 
409 		if (scf_transaction_property_new(tx, e, MHASH_PROP,
410 		    SCF_TYPE_OPAQUE) != SCF_SUCCESS &&
411 		    scf_transaction_property_change_type(tx, e, MHASH_PROP,
412 		    SCF_TYPE_OPAQUE) != SCF_SUCCESS) {
413 			if (errstr != NULL)
414 				*errstr = gettext("Could not modify hash "
415 				    "entry");
416 			result = -1;
417 			goto out;
418 		}
419 
420 		ret = scf_entry_add_value(e, val);
421 		assert(ret == SCF_SUCCESS);
422 
423 		if (scf_transaction_property_new(tx, fe, MHASH_FILE_PROP,
424 		    SCF_TYPE_ASTRING) != SCF_SUCCESS &&
425 		    scf_transaction_property_change_type(tx, fe,
426 		    MHASH_FILE_PROP, SCF_TYPE_ASTRING) != SCF_SUCCESS) {
427 			if (errstr != NULL)
428 				*errstr = gettext("Could not modify file "
429 				    "entry");
430 			result = -1;
431 			goto out;
432 		}
433 
434 		ret = scf_entry_add_value(fe, fval);
435 		assert(ret == SCF_SUCCESS);
436 
437 		switch (apply_late) {
438 		case APPLY_NONE:
439 			if (scf_transaction_property_delete(tx, ae,
440 			    MHASH_APPLY_PROP) != 0) {
441 				err = scf_error();
442 				if ((err != SCF_ERROR_DELETED) &&
443 				    (err != SCF_ERROR_NOT_FOUND)) {
444 					if (errstr != NULL) {
445 						*errstr = gettext("Could not "
446 						    "delete apply_late "
447 						    "property");
448 					}
449 					result = -1;
450 					goto out;
451 				}
452 			}
453 			break;
454 		case APPLY_LATE:
455 			if ((scf_transaction_property_new(tx, ae,
456 			    MHASH_APPLY_PROP,
457 			    SCF_TYPE_BOOLEAN) != SCF_SUCCESS) &&
458 			    (scf_transaction_property_change_type(tx, ae,
459 			    MHASH_APPLY_PROP, SCF_TYPE_BOOLEAN) !=
460 			    SCF_SUCCESS)) {
461 				if (errstr != NULL) {
462 					*errstr = gettext("Could not modify "
463 					    "apply_late property");
464 				}
465 				result = -1;
466 				goto out;
467 			}
468 
469 			ret = scf_entry_add_value(ae, aval);
470 			assert(ret == SCF_SUCCESS);
471 			break;
472 		default:
473 			abort();
474 		};
475 
476 		ret = scf_transaction_commit(tx);
477 
478 		if (ret == 0)
479 			scf_transaction_reset(tx);
480 	} while (ret == 0);
481 
482 	if (ret < 0) {
483 		if (scf_error() != SCF_ERROR_PERMISSION_DENIED) {
484 			if (errstr != NULL)
485 				*errstr = gettext("Could not store file hash: "
486 				    "permission denied.\n");
487 			result = -1;
488 			goto out;
489 		}
490 
491 		if (errstr != NULL)
492 			*errstr = gettext("Could not commit transaction");
493 		result = -1;
494 	}
495 
496 	scf_transaction_destroy(tx);
497 	(void) scf_entry_destroy(e);
498 	(void) scf_entry_destroy(fe);
499 	(void) scf_entry_destroy(ae);
500 
501 out:
502 	(void) scf_value_destroy(val);
503 	(void) scf_value_destroy(fval);
504 	(void) scf_value_destroy(aval);
505 	scf_property_destroy(prop);
506 	scf_pg_destroy(pg);
507 	scf_service_destroy(svc);
508 	scf_scope_destroy(scope);
509 
510 	return (result);
511 }
512 
513 /*
514  * Generate the md5 hash of a file; manifest files are smallish
515  * so we can read them in one gulp.
516  */
517 static int
518 md5_hash_file(const char *file, off64_t sz, uchar_t *hash)
519 {
520 	char *buf;
521 	int fd;
522 	ssize_t res;
523 	int ret;
524 
525 	fd = open(file, O_RDONLY);
526 	if (fd < 0)
527 		return (-1);
528 
529 	buf = malloc(sz);
530 	if (buf == NULL) {
531 		(void) close(fd);
532 		return (-1);
533 	}
534 
535 	res = read(fd, buf, (size_t)sz);
536 
537 	(void) close(fd);
538 
539 	if (res == sz) {
540 		ret = 0;
541 		md5_calc(hash, (uchar_t *)buf, (unsigned int) sz);
542 	} else {
543 		ret = -1;
544 	}
545 
546 	free(buf);
547 	return (ret);
548 }
549 
550 /*
551  * int mhash_test_file(scf_handle_t *, const char *, uint_t, char **, uchar_t *)
552  *   Test the given filename against the hashed metadata in the repository.
553  *   The behaviours for import and apply are slightly different.  For imports,
554  *   if the hash value is absent or different, then the import operation
555  *   continues.  For profile application, the operation continues only if the
556  *   hash value for the file is absent.
557  *
558  *   We keep two hashes: one which can be quickly test: the metadata hash,
559  *   and one which is more expensive to test: the file contents hash.
560  *
561  *   If either hash matches, the file does not need to be re-read.
562  *   If only one of the hashes matches, a side effect of this function
563  *   is to store the newly computed hash.
564  *   If neither hash matches, the hash computed for the new file is returned
565  *   and not stored.
566  *
567  *   Return values:
568  *	MHASH_NEWFILE	- the file no longer matches the hash or no hash existed
569  *			  ONLY in this case we return the new file's hash.
570  *	MHASH_FAILURE	- an internal error occurred, or the file was not found.
571  *	MHASH_RECONCILED- based on the metadata/file hash, the file does
572  *			  not need to be re-read; if necessary,
573  *			  the hash was upgraded or reconciled.
574  *
575  * NOTE: no hash is returned UNLESS MHASH_NEWFILE is returned.
576  */
577 int
578 mhash_test_file(scf_handle_t *hndl, const char *file, uint_t is_profile,
579     char **pnamep, uchar_t *hashbuf)
580 {
581 	apply_action_t action;
582 	boolean_t do_hash;
583 	struct stat64 st;
584 	char *cp;
585 	char *data;
586 	uchar_t stored_hash[MHASH_SIZE];
587 	uchar_t hash[MHASH_SIZE];
588 	char *pname;
589 	int ret;
590 	int hashash;
591 	int metahashok = 0;
592 
593 	if (pnamep)
594 		*pnamep = NULL;
595 
596 	/*
597 	 * In the case where we are doing automated imports, we reduce the UID,
598 	 * the GID, the size, and the mtime into a string (to eliminate
599 	 * endianness) which we then make opaque as a single MD5 digest.
600 	 *
601 	 * The previous hash was composed of the inode number, the UID, the file
602 	 * size, and the mtime.  This formulation was found to be insufficiently
603 	 * portable for use in highly replicated deployments.  The current
604 	 * algorithm will allow matches of this "v1" hash, but always returns
605 	 * the effective "v2" hash, such that updates result in the more
606 	 * portable hash being used.
607 	 *
608 	 * An unwanted side effect of a hash based solely on the file
609 	 * meta data is the fact that we pay no attention to the contents
610 	 * which may remain the same despite meta data changes.  This happens
611 	 * with (live) upgrades.  We extend the V2 hash with an additional
612 	 * digest of the file contents and the code retrieving the hash
613 	 * from the repository zero fills the remainder so we can detect
614 	 * it is missing.
615 	 *
616 	 * If the the V2 digest matches, we check for the presence of
617 	 * the contents digest and compute and store it if missing.
618 	 *
619 	 * If the V2 digest doesn't match but we also have a non-zero
620 	 * file hash, we match the file content digest.  If it matches,
621 	 * we compute and store the new complete hash so that later
622 	 * checks will find the meta data digest correct.
623 	 *
624 	 * If the above matches fail and the V1 hash doesn't match either,
625 	 * we consider the test to have failed, implying that some aspect
626 	 * of the manifest has changed.
627 	 */
628 
629 	cp = getenv("SVCCFG_CHECKHASH");
630 	do_hash = (cp != NULL && *cp != '\0');
631 	if (!do_hash) {
632 		return (MHASH_NEWFILE);
633 	}
634 
635 	pname = mhash_filename_to_propname(file, B_FALSE);
636 	if (pname == NULL)
637 		return (MHASH_FAILURE);
638 
639 	hashash = mhash_retrieve_entry(hndl, pname, stored_hash, &action) == 0;
640 	if (is_profile == 0) {
641 		/* Actions other than APPLY_NONE are restricted to profiles. */
642 		assert(action == APPLY_NONE);
643 	}
644 
645 	/*
646 	 * As a general rule, we do not reread a profile.  The exception to
647 	 * this rule is when we are running as part of the manifest import
648 	 * service and the apply_late property is set to true.
649 	 */
650 	if (hashash && is_profile) {
651 		cp = getenv("SMF_FMRI");
652 		if ((cp == NULL) ||
653 		    (strcmp(cp, SCF_INSTANCE_MI) != 0) ||
654 		    (action != APPLY_LATE)) {
655 			uu_free(pname);
656 			return (MHASH_RECONCILED);
657 		}
658 	}
659 
660 	/*
661 	 * No hash and not interested in one, then don't bother computing it.
662 	 * We also skip returning the property name in that case.
663 	 */
664 	if (!hashash && hashbuf == NULL) {
665 		uu_free(pname);
666 		return (MHASH_NEWFILE);
667 	}
668 
669 	do {
670 		ret = stat64(file, &st);
671 	} while (ret < 0 && errno == EINTR);
672 	if (ret < 0) {
673 		uu_free(pname);
674 		return (MHASH_FAILURE);
675 	}
676 
677 	data = uu_msprintf(MHASH_FORMAT_V2, st.st_uid, st.st_gid,
678 	    st.st_size, st.st_mtime);
679 	if (data == NULL) {
680 		uu_free(pname);
681 		return (MHASH_FAILURE);
682 	}
683 
684 	(void) memset(hash, 0, MHASH_SIZE);
685 	md5_calc(hash, (uchar_t *)data, strlen(data));
686 
687 	uu_free(data);
688 
689 	/*
690 	 * Verify the meta data hash.
691 	 */
692 	if (hashash && memcmp(hash, stored_hash, MD5_DIGEST_LENGTH) == 0) {
693 		int i;
694 
695 		metahashok = 1;
696 		/*
697 		 * The metadata hash matches; now we see if there was a
698 		 * content hash; if not, we will continue on and compute and
699 		 * store the updated hash.
700 		 * If there was no content hash, mhash_retrieve_entry()
701 		 * will have zero filled it.
702 		 */
703 		for (i = 0; i < MD5_DIGEST_LENGTH; i++) {
704 			if (stored_hash[MD5_DIGEST_LENGTH+i] != 0) {
705 				if (action == APPLY_LATE) {
706 					if (pnamep != NULL)
707 						*pnamep = pname;
708 					ret = MHASH_NEWFILE;
709 				} else {
710 					uu_free(pname);
711 					ret = MHASH_RECONCILED;
712 				}
713 				return (ret);
714 			}
715 		}
716 	}
717 
718 	/*
719 	 * Compute the file hash as we can no longer avoid having to know it.
720 	 * Note: from this point on "hash" contains the full, current, hash.
721 	 */
722 	if (md5_hash_file(file, st.st_size, &hash[MHASH_SIZE_OLD]) != 0) {
723 		uu_free(pname);
724 		return (MHASH_FAILURE);
725 	}
726 	if (hashash) {
727 		uchar_t hash_v1[MHASH_SIZE_OLD];
728 
729 		if (metahashok ||
730 		    memcmp(&hash[MHASH_SIZE_OLD], &stored_hash[MHASH_SIZE_OLD],
731 		    MD5_DIGEST_LENGTH) == 0) {
732 
733 			/*
734 			 * Reconcile entry: we get here when either the
735 			 * meta data hash matches or the content hash matches;
736 			 * we then update the database with the complete
737 			 * new hash so we can be a bit quicker next time.
738 			 */
739 			(void) mhash_store_entry(hndl, pname, file, hash,
740 			    APPLY_NONE, NULL);
741 			if (action == APPLY_LATE) {
742 				if (pnamep != NULL)
743 					*pnamep = pname;
744 				ret = MHASH_NEWFILE;
745 			} else {
746 				uu_free(pname);
747 				ret = MHASH_RECONCILED;
748 			}
749 			return (ret);
750 		}
751 
752 		/*
753 		 * No match on V2 hash or file content; compare V1 hash.
754 		 */
755 		data = uu_msprintf(MHASH_FORMAT_V1, st.st_ino, st.st_uid,
756 		    st.st_size, st.st_mtime);
757 		if (data == NULL) {
758 			uu_free(pname);
759 			return (MHASH_FAILURE);
760 		}
761 
762 		md5_calc(hash_v1, (uchar_t *)data, strlen(data));
763 
764 		uu_free(data);
765 
766 		if (memcmp(hash_v1, stored_hash, MD5_DIGEST_LENGTH) == 0) {
767 			/*
768 			 * Update the new entry so we don't have to go through
769 			 * all this trouble next time.
770 			 */
771 			(void) mhash_store_entry(hndl, pname, file, hash,
772 			    APPLY_NONE, NULL);
773 			uu_free(pname);
774 			return (MHASH_RECONCILED);
775 		}
776 	}
777 
778 	if (pnamep != NULL)
779 		*pnamep = pname;
780 	else
781 		uu_free(pname);
782 
783 	if (hashbuf != NULL)
784 		(void) memcpy(hashbuf, hash, MHASH_SIZE);
785 
786 	return (MHASH_NEWFILE);
787 }
788