xref: /titanic_51/usr/src/lib/smbsrv/libsmb/common/smb_util.c (revision 49fbdd30212f016ddd49c4b5c997b0b827ff0962)
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <ctype.h>
27 #include <stdio.h>
28 #include <string.h>
29 #include <stdlib.h>
30 #include <pthread.h>
31 #include <sys/varargs.h>
32 #include <sys/types.h>
33 #include <smbsrv/string.h>
34 #include <smbsrv/libsmb.h>
35 #include <tiuser.h>
36 #include <netconfig.h>
37 #include <netdir.h>
38 #include <sys/systeminfo.h>
39 #include <sys/utsname.h>
40 
41 static uint_t smb_make_mask(char *, uint_t);
42 static boolean_t smb_netmatch(struct netbuf *, char *);
43 static boolean_t smb_netgroup_match(struct nd_hostservlist *, char *, int);
44 
45 extern  int __multi_innetgr();
46 extern int __netdir_getbyaddr_nosrv(struct netconfig *,
47     struct nd_hostservlist **, struct netbuf *);
48 
49 #define	C2H(c)		"0123456789ABCDEF"[(c)]
50 #define	H2C(c)    (((c) >= '0' && (c) <= '9') ? ((c) - '0') :     \
51 	((c) >= 'a' && (c) <= 'f') ? ((c) - 'a' + 10) :         \
52 	((c) >= 'A' && (c) <= 'F') ? ((c) - 'A' + 10) :         \
53 	'\0')
54 #define	DEFAULT_SBOX_SIZE		256
55 
56 /*
57  *
58  * hexdump
59  *
60  * Simple hex dump display function. Displays nbytes of buffer in hex and
61  * printable format. Non-printing characters are shown as '.'. It is safe
62  * to pass a null pointer. Each line begins with the offset. If nbytes is
63  * 0, the line will be blank except for the offset. Example output:
64  *
65  * 00000000  54 68 69 73 20 69 73 20 61 20 70 72 6F 67 72 61  This is a progra
66  * 00000010  6D 20 74 65 73 74 2E 00                          m test..
67  *
68  */
69 void
70 hexdump_offset(unsigned char *buffer, int nbytes, unsigned long *start)
71 {
72 	static char *hex = "0123456789ABCDEF";
73 	int i, count;
74 	int offset;
75 	unsigned char *p;
76 	char ascbuf[64];
77 	char hexbuf[64];
78 	char *ap = ascbuf;
79 	char *hp = hexbuf;
80 
81 	if ((p = buffer) == NULL)
82 		return;
83 
84 	offset = *start;
85 
86 	*ap = '\0';
87 	*hp = '\0';
88 	count = 0;
89 
90 	for (i = 0; i < nbytes; ++i) {
91 		if (i && (i % 16) == 0) {
92 			smb_tracef("%06X %s  %s", offset, hexbuf, ascbuf);
93 			ap = ascbuf;
94 			hp = hexbuf;
95 			count = 0;
96 			offset += 16;
97 		}
98 
99 		ap += sprintf(ap, "%c",
100 		    (*p >= 0x20 && *p < 0x7F) ? *p : '.');
101 		hp += sprintf(hp, " %c%c",
102 		    hex[(*p >> 4) & 0x0F], hex[(*p & 0x0F)]);
103 		++p;
104 		++count;
105 	}
106 
107 	if (count) {
108 		smb_tracef("%06X %-48s  %s", offset, hexbuf, ascbuf);
109 		offset += count;
110 	}
111 
112 	*start = offset;
113 }
114 
115 void
116 hexdump(unsigned char *buffer, int nbytes)
117 {
118 	unsigned long start = 0;
119 
120 	hexdump_offset(buffer, nbytes, &start);
121 }
122 
123 /*
124  * bintohex
125  *
126  * Converts the given binary data (srcbuf) to
127  * its equivalent hex chars (hexbuf).
128  *
129  * hexlen should be at least twice as srclen.
130  * if hexbuf is not big enough returns 0.
131  * otherwise returns number of valid chars in
132  * hexbuf which is srclen * 2.
133  */
134 size_t
135 bintohex(const char *srcbuf, size_t srclen,
136     char *hexbuf, size_t hexlen)
137 {
138 	size_t outlen;
139 	char c;
140 
141 	outlen = srclen << 1;
142 
143 	if (hexlen < outlen)
144 		return (0);
145 
146 	while (srclen-- > 0) {
147 		c = *srcbuf++;
148 		*hexbuf++ = C2H(c & 0xF);
149 		*hexbuf++ = C2H((c >> 4) & 0xF);
150 	}
151 
152 	return (outlen);
153 }
154 
155 /*
156  * hextobin
157  *
158  * Converts hex to binary.
159  *
160  * Assuming hexbuf only contains hex digits (chars)
161  * this function convert every two bytes of hexbuf
162  * to one byte and put it in dstbuf.
163  *
164  * hexlen should be an even number.
165  * dstlen should be at least half of hexlen.
166  *
167  * Returns 0 if sizes are not correct, otherwise
168  * returns the number of converted bytes in dstbuf
169  * which is half of hexlen.
170  */
171 size_t
172 hextobin(const char *hexbuf, size_t hexlen,
173     char *dstbuf, size_t dstlen)
174 {
175 	size_t outlen;
176 
177 	if ((hexlen % 2) != 0)
178 		return (0);
179 
180 	outlen = hexlen >> 1;
181 	if (dstlen < outlen)
182 		return (0);
183 
184 	while (hexlen > 0) {
185 		*dstbuf = H2C(*hexbuf) & 0x0F;
186 		hexbuf++;
187 		*dstbuf++ |= (H2C(*hexbuf) << 4) & 0xF0;
188 		hexbuf++;
189 
190 		hexlen -= 2;
191 	}
192 
193 	return (outlen);
194 }
195 
196 /*
197  * trim_whitespace
198  *
199  * Trim leading and trailing whitespace chars (as defined by isspace)
200  * from a buffer. Example; if the input buffer contained "  text  ",
201  * it will contain "text", when we return. We assume that the buffer
202  * contains a null terminated string. A pointer to the buffer is
203  * returned.
204  */
205 char *
206 trim_whitespace(char *buf)
207 {
208 	char *p = buf;
209 	char *q = buf;
210 
211 	if (buf == NULL)
212 		return (NULL);
213 
214 	while (*p && isspace(*p))
215 		++p;
216 
217 	while ((*q = *p++) != 0)
218 		++q;
219 
220 	if (q != buf) {
221 		while ((--q, isspace(*q)) != 0)
222 			*q = '\0';
223 	}
224 
225 	return (buf);
226 }
227 
228 /*
229  * randomize
230  *
231  * Randomize the contents of the specified buffer.
232  */
233 void
234 randomize(char *data, unsigned len)
235 {
236 	unsigned dwlen = len / 4;
237 	unsigned remlen = len % 4;
238 	unsigned tmp;
239 	unsigned i; /*LINTED E_BAD_PTR_CAST_ALIGN*/
240 	unsigned *p = (unsigned *)data;
241 
242 	for (i = 0; i < dwlen; ++i)
243 		*p++ = random();
244 
245 	if (remlen) {
246 		tmp = random();
247 		(void) memcpy(p, &tmp, remlen);
248 	}
249 }
250 
251 /*
252  * This is the hash mechanism used to encrypt passwords for commands like
253  * SamrSetUserInformation. It uses a 256 byte s-box.
254  */
255 void
256 rand_hash(
257     unsigned char *data,
258     size_t datalen,
259     unsigned char *key,
260     size_t keylen)
261 {
262 	unsigned char sbox[DEFAULT_SBOX_SIZE];
263 	unsigned char tmp;
264 	unsigned char index_i = 0;
265 	unsigned char index_j = 0;
266 	unsigned char j = 0;
267 	int i;
268 
269 	for (i = 0; i < DEFAULT_SBOX_SIZE; ++i)
270 		sbox[i] = (unsigned char)i;
271 
272 	for (i = 0; i < DEFAULT_SBOX_SIZE; ++i) {
273 		j += (sbox[i] + key[i % keylen]);
274 
275 		tmp = sbox[i];
276 		sbox[i] = sbox[j];
277 		sbox[j] = tmp;
278 	}
279 
280 	for (i = 0; i < datalen; ++i) {
281 		index_i++;
282 		index_j += sbox[index_i];
283 
284 		tmp = sbox[index_i];
285 		sbox[index_i] = sbox[index_j];
286 		sbox[index_j] = tmp;
287 
288 		tmp = sbox[index_i] + sbox[index_j];
289 		data[i] = data[i] ^ sbox[tmp];
290 	}
291 }
292 
293 /*
294  * smb_chk_hostaccess
295  *
296  * Determine whether an access list grants rights to a particular host.
297  * We match on aliases of the hostname as well as on the canonical name.
298  * Names in the access list may be either hosts or netgroups;  they're
299  * not distinguished syntactically.  We check for hosts first because
300  * it's cheaper (just M*N strcmp()s), then try netgroups.
301  *
302  * Function returns:
303  *	-1 for "all"
304  *	0 not found
305  *	1 found
306  */
307 int
308 smb_chk_hostaccess(ipaddr_t ipaddr, char *access_list)
309 {
310 	int nentries;
311 	char *gr;
312 	char *lasts;
313 	char *host;
314 	int off;
315 	int i;
316 	int netgroup_match;
317 	int response;
318 	struct nd_hostservlist *clnames;
319 	struct in_addr inaddr;
320 	struct sockaddr_in sa;
321 	struct netbuf buf;
322 	struct netconfig *config;
323 
324 	inaddr.s_addr = (uint32_t)ipaddr;
325 
326 	/*
327 	 * If no access list - then it's "all"
328 	 */
329 	if (access_list == NULL || *access_list == '\0' ||
330 	    strcmp(access_list, "*") == 0)
331 		return (-1);
332 
333 	nentries = 0;
334 
335 	/* For now, only IPv4 */
336 
337 	sa.sin_family = AF_INET;
338 	sa.sin_port = 0;
339 	sa.sin_addr = inaddr;
340 
341 	buf.len = buf.maxlen = sizeof (sa);
342 	buf.buf = (char *)&sa;
343 
344 	config = getnetconfigent("tcp");
345 	if (config == NULL)
346 		return (1);
347 
348 	if (__netdir_getbyaddr_nosrv(config, &clnames, &buf)) {
349 		freenetconfigent(config);
350 		return (0);
351 	}
352 	freenetconfigent(config);
353 
354 	for (gr = strtok_r(access_list, ":", &lasts);
355 	    gr != NULL; gr = strtok_r(NULL, ":", &lasts)) {
356 
357 		/*
358 		 * If the list name has a '-' prepended
359 		 * then a match of the following name
360 		 * implies failure instead of success.
361 		 */
362 		if (*gr == '-') {
363 			response = 0;
364 			gr++;
365 		} else {
366 			response = 1;
367 		}
368 
369 		/*
370 		 * The following loops through all the
371 		 * client's aliases.  Usually it's just one name.
372 		 */
373 		for (i = 0; i < clnames->h_cnt; i++) {
374 			host = clnames->h_hostservs[i].h_host;
375 			/*
376 			 * If the list name begins with a dot then
377 			 * do a domain name suffix comparison.
378 			 * A single dot matches any name with no
379 			 * suffix.
380 			 */
381 			if (*gr == '.') {
382 				if (*(gr + 1) == '\0') {  /* single dot */
383 					if (strchr(host, '.') == NULL)
384 						return (response);
385 				} else {
386 					off = strlen(host) - strlen(gr);
387 					if (off > 0 &&
388 					    strcasecmp(host + off, gr) == 0) {
389 						return (response);
390 					}
391 				}
392 			} else {
393 
394 				/*
395 				 * If the list name begins with an at
396 				 * sign then do a network comparison.
397 				 */
398 				if (*gr == '@') {
399 					if (smb_netmatch(&buf, gr + 1))
400 						return (response);
401 				} else {
402 					/*
403 					 * Just do a hostname match
404 					 */
405 					if (strcasecmp(gr, host) == 0)
406 						return (response);
407 				}
408 			}
409 		}
410 
411 		nentries++;
412 	}
413 
414 	netgroup_match = smb_netgroup_match(clnames, access_list, nentries);
415 
416 	return (netgroup_match);
417 }
418 
419 /*
420  * smb_make_mask
421  *
422  * Construct a mask for an IPv4 address using the @<dotted-ip>/<len>
423  * syntax or use the default mask for the IP address.
424  */
425 static uint_t
426 smb_make_mask(char *maskstr, uint_t addr)
427 {
428 	uint_t mask;
429 	uint_t bits;
430 
431 	/*
432 	 * If the mask is specified explicitly then
433 	 * use that value, e.g.
434 	 *
435 	 *    @109.104.56/28
436 	 *
437 	 * otherwise assume a mask from the zero octets
438 	 * in the least significant bits of the address, e.g.
439 	 *
440 	 *   @109.104  or  @109.104.0.0
441 	 */
442 	if (maskstr) {
443 		bits = atoi(maskstr);
444 		mask = bits ? ~0 << ((sizeof (struct in_addr) * NBBY) - bits)
445 		    : 0;
446 		addr &= mask;
447 	} else {
448 		if ((addr & IN_CLASSA_HOST) == 0)
449 			mask = IN_CLASSA_NET;
450 		else if ((addr & IN_CLASSB_HOST) == 0)
451 			mask = IN_CLASSB_NET;
452 		else if ((addr & IN_CLASSC_HOST) == 0)
453 			mask = IN_CLASSC_NET;
454 		else
455 			mask = IN_CLASSE_NET;
456 	}
457 
458 	return (mask);
459 }
460 
461 /*
462  * smb_netmatch
463  *
464  * Check to see if the address in the netbuf matches the "net"
465  * specified by name.  The format of "name" can be:
466  *	fully qualified domain name
467  *	dotted IP address
468  *	dotted IP address followed by '/<len>'
469  *	See sharen_nfs(1M) for details.
470  */
471 
472 static boolean_t
473 smb_netmatch(struct netbuf *nb, char *name)
474 {
475 	uint_t claddr;
476 	struct netent n, *np;
477 	char *mp, *p;
478 	uint_t addr, mask;
479 	int i;
480 	char buff[256];
481 
482 	/*
483 	 * Check if it's an IPv4 addr
484 	 */
485 	if (nb->len != sizeof (struct sockaddr_in))
486 		return (B_FALSE);
487 
488 	(void) memcpy(&claddr,
489 	    /* LINTED pointer alignment */
490 	    &((struct sockaddr_in *)nb->buf)->sin_addr.s_addr,
491 	    sizeof (struct in_addr));
492 	claddr = ntohl(claddr);
493 
494 	mp = strchr(name, '/');
495 	if (mp)
496 		*mp++ = '\0';
497 
498 	if (isdigit(*name)) {
499 		/*
500 		 * Convert a dotted IP address
501 		 * to an IP address. The conversion
502 		 * is not the same as that in inet_addr().
503 		 */
504 		p = name;
505 		addr = 0;
506 		for (i = 0; i < 4; i++) {
507 			addr |= atoi(p) << ((3-i) * 8);
508 			p = strchr(p, '.');
509 			if (p == NULL)
510 				break;
511 			p++;
512 		}
513 	} else {
514 		/*
515 		 * Turn the netname into
516 		 * an IP address.
517 		 */
518 		np = getnetbyname_r(name, &n, buff, sizeof (buff));
519 		if (np == NULL) {
520 			return (B_FALSE);
521 		}
522 		addr = np->n_net;
523 	}
524 
525 	mask = smb_make_mask(mp, addr);
526 	return ((claddr & mask) == addr);
527 }
528 
529 /*
530  * smb_netgroup_match
531  *
532  * Check whether any of the hostnames in clnames are
533  * members (or non-members) of the netgroups in glist.
534  * Since the innetgr lookup is rather expensive, the
535  * result is cached. The cached entry is valid only
536  * for VALID_TIME seconds.  This works well because
537  * typically these lookups occur in clusters when
538  * a client is mounting.
539  *
540  * Note that this routine establishes a host membership
541  * in a list of netgroups - we've no idea just which
542  * netgroup in the list it is a member of.
543  *
544  * glist is a character array containing grc strings
545  * representing netgroup names (optionally prefixed
546  * with '-'). Each string is ended with '\0'  and
547  * followed immediately by the next string.
548  */
549 static boolean_t
550 smb_netgroup_match(struct nd_hostservlist *clnames, char  *glist, int grc)
551 {
552 	char **grl;
553 	char *gr;
554 	int nhosts = clnames->h_cnt;
555 	char *host;
556 	int i, j, n;
557 	boolean_t response;
558 	boolean_t belong = B_FALSE;
559 	static char *domain = NULL;
560 
561 	if (domain == NULL) {
562 		int	ssize;
563 
564 		domain = malloc(SYS_NMLN);
565 		if (domain == NULL)
566 			return (B_FALSE);
567 
568 		ssize = sysinfo(SI_SRPC_DOMAIN, domain, SYS_NMLN);
569 		if (ssize > SYS_NMLN) {
570 			free(domain);
571 			domain = malloc(ssize);
572 			if (domain == NULL)
573 				return (B_FALSE);
574 			ssize = sysinfo(SI_SRPC_DOMAIN, domain, ssize);
575 		}
576 		/* Check for error in syscall or NULL domain name */
577 		if (ssize <= 1)
578 			return (B_FALSE);
579 	}
580 
581 	grl = calloc(grc, sizeof (char *));
582 	if (grl == NULL)
583 		return (B_FALSE);
584 
585 	for (i = 0, gr = glist; i < grc && !belong; ) {
586 		/*
587 		 * If the netgroup name has a '-' prepended
588 		 * then a match of this name implies a failure
589 		 * instead of success.
590 		 */
591 		response = (*gr != '-') ? B_TRUE : B_FALSE;
592 
593 		/*
594 		 * Subsequent names with or without a '-' (but no mix)
595 		 * can be grouped together for a single check.
596 		 */
597 		for (n = 0; i < grc; i++, n++, gr += strlen(gr) + 1) {
598 			if ((response && *gr == '-') ||
599 			    (!response && *gr != '-'))
600 				break;
601 
602 			grl[n] = response ? gr : gr + 1;
603 		}
604 
605 		/*
606 		 * Check the netgroup for each
607 		 * of the hosts names (usually just one).
608 		 */
609 		for (j = 0; j < nhosts && !belong; j++) {
610 			host = clnames->h_hostservs[j].h_host;
611 			if (__multi_innetgr(n, grl, 1, &host, 0, NULL,
612 			    1, &domain))
613 				belong = B_TRUE;
614 		}
615 	}
616 
617 	free(grl);
618 	return (belong ? response : B_FALSE);
619 }
620