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 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <sys/types.h>
29 #include <string.h>
30 #include <stdlib.h>
31 #include <stdio.h>
32 #include <errno.h>
33 #include <stdarg.h>
34 #include <limits.h>
35 #include <ctype.h>
36 #include <libgen.h>
37 #include <sys/isa_defs.h>
38 #include <sys/socket.h>
39 #include <net/if_arp.h>
40 #include <netinet/in.h>
41 #include <arpa/inet.h>
42 #include <sys/sysmacros.h>
43 #include <libinetutil.h>
44 #include <libdlpi.h>
45 #include <netinet/dhcp6.h>
46 
47 #include "dhcp_symbol.h"
48 #include "dhcp_inittab.h"
49 
50 static uint64_t		dhcp_htonll(uint64_t);
51 static uint64_t		dhcp_ntohll(uint64_t);
52 static void		inittab_msg(const char *, ...);
53 static uchar_t		category_to_code(const char *);
54 static boolean_t	encode_number(uint8_t, uint8_t, boolean_t, uint8_t,
55 			    const char *, uint8_t *, int *);
56 static boolean_t	decode_number(uint8_t, uint8_t, boolean_t, uint8_t,
57 			    const uint8_t *, char *, int *);
58 static dhcp_symbol_t	*inittab_lookup(uchar_t, char, const char *, int32_t,
59 			    size_t *);
60 static dsym_category_t	itabcode_to_dsymcode(uchar_t);
61 static boolean_t	parse_entry(char *, char **);
62 
63 /*
64  * forward declaration of our internal inittab_table[].  too bulky to put
65  * up front -- check the end of this file for its definition.
66  *
67  * Note: we have only an IPv4 version here.  The inittab_verify() function is
68  * used by the DHCP server and manager.  We'll need a new function if the
69  * server is extended to DHCPv6.
70  */
71 static dhcp_symbol_t	inittab_table[];
72 
73 /*
74  * the number of fields in the inittab and names for the fields.  note that
75  * this order is meaningful to parse_entry(); other functions should just
76  * use them as indexes into the array returned from parse_entry().
77  */
78 #define	ITAB_FIELDS	7
79 enum { ITAB_NAME, ITAB_CODE, ITAB_TYPE, ITAB_GRAN, ITAB_MAX, ITAB_CONS,
80     ITAB_CAT };
81 
82 /*
83  * the category_map_entry_t is used to map the inittab category codes to
84  * the dsym codes.  the reason the codes are different is that the inittab
85  * needs to have the codes be ORable such that queries can retrieve more
86  * than one category at a time.  this map is also used to map the inittab
87  * string representation of a category to its numerical code.
88  */
89 typedef struct category_map_entry {
90 	dsym_category_t	cme_dsymcode;
91 	char		*cme_name;
92 	uchar_t		cme_itabcode;
93 } category_map_entry_t;
94 
95 static category_map_entry_t category_map[] = {
96 	{ DSYM_STANDARD,	"STANDARD",	ITAB_CAT_STANDARD },
97 	{ DSYM_FIELD,		"FIELD",	ITAB_CAT_FIELD },
98 	{ DSYM_INTERNAL,	"INTERNAL",	ITAB_CAT_INTERNAL },
99 	{ DSYM_VENDOR,		"VENDOR",	ITAB_CAT_VENDOR },
100 	{ DSYM_SITE,		"SITE",		ITAB_CAT_SITE }
101 };
102 
103 /*
104  * dlpi_to_arp(): converts DLPI datalink types into ARP datalink types
105  *
106  *   input: uint_t: the DLPI datalink type
107  *  output: uint_t: the ARP datalink type (0 if no corresponding code)
108  *
109  *    note: this function does not belong in this library, but it's here until
110  *	    dhcpagent is ported over to libdlpi.  It should move to libdlpi
111  *	    instead.
112  */
113 
114 uint_t
115 dlpi_to_arp(uint_t dlpi_type)
116 {
117 	switch (dlpi_type) {
118 
119 	case DL_ETHER:
120 		return (ARPHRD_ETHER);
121 
122 	case DL_FRAME:
123 		return (ARPHRD_FRAME);
124 
125 	case DL_ATM:
126 		return (ARPHRD_ATM);
127 
128 	case DL_IPATM:
129 		return (ARPHRD_IPATM);
130 
131 	case DL_HDLC:
132 		return (ARPHRD_HDLC);
133 
134 	case DL_FC:
135 		return (ARPHRD_FC);
136 
137 	case DL_CSMACD:				/* ieee 802 networks */
138 	case DL_TPB:
139 	case DL_TPR:
140 	case DL_METRO:
141 	case DL_FDDI:
142 		return (ARPHRD_IEEE802);
143 
144 	case DL_IB:
145 		return (ARPHRD_IB);
146 
147 	case DL_IPV4:
148 	case DL_IPV6:
149 		return (ARPHRD_TUNNEL);
150 	}
151 
152 	return (0);
153 }
154 
155 /*
156  * inittab_load(): returns all inittab entries with the specified criteria
157  *
158  *   input: uchar_t: the categories the consumer is interested in
159  *	    char: the consumer type of the caller
160  *	    size_t *: set to the number of entries returned
161  *  output: dhcp_symbol_t *: an array of dynamically allocated entries
162  *	    on success, NULL upon failure
163  */
164 
165 dhcp_symbol_t	*
166 inittab_load(uchar_t categories, char consumer, size_t *n_entries)
167 {
168 	return (inittab_lookup(categories, consumer, NULL, -1, n_entries));
169 }
170 
171 /*
172  * inittab_getbyname(): returns an inittab entry with the specified criteria
173  *
174  *   input: int: the categories the consumer is interested in
175  *	    char: the consumer type of the caller
176  *	    char *: the name of the inittab entry the consumer wants
177  *  output: dhcp_symbol_t *: a dynamically allocated dhcp_symbol structure
178  *	    on success, NULL upon failure
179  */
180 
181 dhcp_symbol_t	*
182 inittab_getbyname(uchar_t categories, char consumer, const char *name)
183 {
184 	return (inittab_lookup(categories, consumer, name, -1, NULL));
185 }
186 
187 /*
188  * inittab_getbycode(): returns an inittab entry with the specified criteria
189  *
190  *   input: uchar_t: the categories the consumer is interested in
191  *	    char: the consumer type of the caller
192  *	    uint16_t: the code of the inittab entry the consumer wants
193  *  output: dhcp_symbol_t *: a dynamically allocated dhcp_symbol structure
194  *	    on success, NULL upon failure
195  */
196 
197 dhcp_symbol_t	*
198 inittab_getbycode(uchar_t categories, char consumer, uint16_t code)
199 {
200 	return (inittab_lookup(categories, consumer, NULL, code, NULL));
201 }
202 
203 /*
204  * inittab_lookup(): returns inittab entries with the specified criteria
205  *
206  *   input: uchar_t: the categories the consumer is interested in
207  *	    char: the consumer type of the caller
208  *	    const char *: the name of the entry the caller is interested
209  *		in, or NULL if the caller doesn't care
210  *	    int32_t: the code the caller is interested in, or -1 if the
211  *		caller doesn't care
212  *	    size_t *: set to the number of entries returned
213  *  output: dhcp_symbol_t *: dynamically allocated dhcp_symbol structures
214  *	    on success, NULL upon failure
215  */
216 
217 static dhcp_symbol_t *
218 inittab_lookup(uchar_t categories, char consumer, const char *name,
219     int32_t code, size_t *n_entriesp)
220 {
221 	FILE			*inittab_fp;
222 	dhcp_symbol_t		*new_entries, *entries = NULL;
223 	dhcp_symbol_t		entry;
224 	char			buffer[ITAB_MAX_LINE_LEN];
225 	char			*fields[ITAB_FIELDS];
226 	unsigned long		line = 0;
227 	size_t			i, n_entries = 0;
228 	const char		*inittab_path;
229 	uchar_t			category_code;
230 	dsym_cdtype_t		type;
231 
232 	if (categories & ITAB_CAT_V6) {
233 		inittab_path = getenv("DHCP_INITTAB6_PATH");
234 		if (inittab_path == NULL)
235 			inittab_path = ITAB_INITTAB6_PATH;
236 	} else {
237 		inittab_path = getenv("DHCP_INITTAB_PATH");
238 		if (inittab_path == NULL)
239 			inittab_path = ITAB_INITTAB_PATH;
240 	}
241 
242 	inittab_fp = fopen(inittab_path, "r");
243 	if (inittab_fp == NULL) {
244 		inittab_msg("inittab_lookup: fopen: %s: %s",
245 		    inittab_path, strerror(errno));
246 		return (NULL);
247 	}
248 
249 	(void) bufsplit(",\n", 0, NULL);
250 	while (fgets(buffer, sizeof (buffer), inittab_fp) != NULL) {
251 
252 		line++;
253 
254 		/*
255 		 * make sure the string didn't overflow our buffer
256 		 */
257 		if (strchr(buffer, '\n') == NULL) {
258 			inittab_msg("inittab_lookup: line %li: too long, "
259 			    "skipping", line);
260 			continue;
261 		}
262 
263 		/*
264 		 * skip `pure comment' lines
265 		 */
266 		for (i = 0; buffer[i] != '\0'; i++)
267 			if (isspace(buffer[i]) == 0)
268 				break;
269 
270 		if (buffer[i] == ITAB_COMMENT_CHAR || buffer[i] == '\0')
271 			continue;
272 
273 		/*
274 		 * parse the entry out into fields.
275 		 */
276 		if (parse_entry(buffer, fields) == B_FALSE) {
277 			inittab_msg("inittab_lookup: line %li: syntax error, "
278 			    "skipping", line);
279 			continue;
280 		}
281 
282 		/*
283 		 * validate the values in the entries; skip if invalid.
284 		 */
285 		if (atoi(fields[ITAB_GRAN]) > ITAB_GRAN_MAX) {
286 			inittab_msg("inittab_lookup: line %li: granularity `%s'"
287 			    " out of range, skipping", line, fields[ITAB_GRAN]);
288 			continue;
289 		}
290 
291 		if (atoi(fields[ITAB_MAX]) > ITAB_MAX_MAX) {
292 			inittab_msg("inittab_lookup: line %li: maximum `%s' "
293 			    "out of range, skipping", line, fields[ITAB_MAX]);
294 			continue;
295 		}
296 
297 		if (dsym_get_type_id(fields[ITAB_TYPE], &type, B_FALSE) !=
298 		    DSYM_SUCCESS) {
299 			inittab_msg("inittab_lookup: line %li: type `%s' "
300 			    "is invalid, skipping", line, fields[ITAB_TYPE]);
301 			continue;
302 		}
303 
304 		/*
305 		 * find out whether this entry of interest to our consumer,
306 		 * and if so, throw it onto the set of entries we'll return.
307 		 * check categories last since it's the most expensive check.
308 		 */
309 		if (strchr(fields[ITAB_CONS], consumer) == NULL)
310 			continue;
311 
312 		if (code != -1 && atoi(fields[ITAB_CODE]) != code)
313 			continue;
314 
315 		if (name != NULL && strcasecmp(fields[ITAB_NAME], name) != 0)
316 			continue;
317 
318 		category_code = category_to_code(fields[ITAB_CAT]);
319 		if ((category_code & categories) == 0)
320 			continue;
321 
322 		/*
323 		 * looks like a match.  allocate an entry and fill it in
324 		 */
325 		new_entries = realloc(entries, (n_entries + 1) *
326 		    sizeof (dhcp_symbol_t));
327 
328 		/*
329 		 * if we run out of memory, might as well return what we can
330 		 */
331 		if (new_entries == NULL) {
332 			inittab_msg("inittab_lookup: ran out of memory "
333 			    "allocating dhcp_symbol_t's");
334 			break;
335 		}
336 
337 		entry.ds_max	  = atoi(fields[ITAB_MAX]);
338 		entry.ds_code	  = atoi(fields[ITAB_CODE]);
339 		entry.ds_type	  = type;
340 		entry.ds_gran	  = atoi(fields[ITAB_GRAN]);
341 		entry.ds_category = itabcode_to_dsymcode(category_code);
342 		entry.ds_classes.dc_cnt	  = 0;
343 		entry.ds_classes.dc_names = NULL;
344 		(void) strlcpy(entry.ds_name, fields[ITAB_NAME],
345 		    sizeof (entry.ds_name));
346 		entry.ds_dhcpv6	  = (categories & ITAB_CAT_V6) ? 1 : 0;
347 
348 		entries = new_entries;
349 		entries[n_entries++] = entry;
350 	}
351 
352 	if (ferror(inittab_fp) != 0) {
353 		inittab_msg("inittab_lookup: error on inittab stream");
354 		clearerr(inittab_fp);
355 	}
356 
357 	(void) fclose(inittab_fp);
358 
359 	if (n_entriesp != NULL)
360 		*n_entriesp = n_entries;
361 
362 	return (entries);
363 }
364 
365 /*
366  * parse_entry(): parses an entry out into its constituent fields
367  *
368  *   input: char *: the entry
369  *	    char **: an array of ITAB_FIELDS length which contains
370  *		     pointers into the entry on upon return
371  *  output: boolean_t: B_TRUE on success, B_FALSE on failure
372  */
373 
374 static boolean_t
375 parse_entry(char *entry, char **fields)
376 {
377 	char	*category, *spacep;
378 	size_t	n_fields, i;
379 
380 	/*
381 	 * due to a mistake made long ago, the first and second fields of
382 	 * each entry are not separated by a comma, but rather by
383 	 * whitespace -- have bufsplit() treat the two fields as one, then
384 	 * pull them apart afterwards.
385 	 */
386 	n_fields = bufsplit(entry, ITAB_FIELDS - 1, fields);
387 	if (n_fields != (ITAB_FIELDS - 1))
388 		return (B_FALSE);
389 
390 	/*
391 	 * pull the first and second fields apart.  this is complicated
392 	 * since the first field can contain embedded whitespace (so we
393 	 * must separate the two fields by the last span of whitespace).
394 	 *
395 	 * first, find the initial span of whitespace.  if there isn't one,
396 	 * then the entry is malformed.
397 	 */
398 	category = strpbrk(fields[ITAB_NAME], " \t");
399 	if (category == NULL)
400 		return (B_FALSE);
401 
402 	/*
403 	 * find the last span of whitespace.
404 	 */
405 	do {
406 		while (isspace(*category))
407 			category++;
408 
409 		spacep = strpbrk(category, " \t");
410 		if (spacep != NULL)
411 			category = spacep;
412 	} while (spacep != NULL);
413 
414 	/*
415 	 * NUL-terminate the first byte of the last span of whitespace, so
416 	 * that the first field doesn't have any residual trailing
417 	 * whitespace.
418 	 */
419 	spacep = category - 1;
420 	while (isspace(*spacep))
421 		spacep--;
422 
423 	if (spacep <= fields[0])
424 		return (B_FALSE);
425 
426 	*++spacep = '\0';
427 
428 	/*
429 	 * remove any whitespace from the fields.
430 	 */
431 	for (i = 0; i < n_fields; i++) {
432 		while (isspace(*fields[i]))
433 			fields[i]++;
434 	}
435 	fields[ITAB_CAT] = category;
436 
437 	return (B_TRUE);
438 }
439 
440 /*
441  * inittab_verify(): verifies that a given inittab entry matches an internal
442  *		     definition
443  *
444  *   input: dhcp_symbol_t *: the inittab entry to verify
445  *	    dhcp_symbol_t *: if non-NULL, a place to store the internal
446  *			       inittab entry upon return
447  *  output: int: ITAB_FAILURE, ITAB_SUCCESS, or ITAB_UNKNOWN
448  *
449  *   notes: IPv4 only
450  */
451 
452 int
453 inittab_verify(const dhcp_symbol_t *inittab_ent, dhcp_symbol_t *internal_ent)
454 {
455 	unsigned int	i;
456 
457 	for (i = 0; inittab_table[i].ds_name[0] != '\0'; i++) {
458 
459 		if (inittab_ent->ds_category != inittab_table[i].ds_category)
460 			continue;
461 
462 		if (inittab_ent->ds_code == inittab_table[i].ds_code) {
463 			if (internal_ent != NULL)
464 				*internal_ent = inittab_table[i];
465 
466 			if (inittab_table[i].ds_type != inittab_ent->ds_type ||
467 			    inittab_table[i].ds_gran != inittab_ent->ds_gran ||
468 			    inittab_table[i].ds_max  != inittab_ent->ds_max)
469 				return (ITAB_FAILURE);
470 
471 			return (ITAB_SUCCESS);
472 		}
473 	}
474 
475 	return (ITAB_UNKNOWN);
476 }
477 
478 /*
479  * get_hw_type(): interpret ",hwtype" in the input string, as part of a DUID.
480  *		  The hwtype string is optional, and must be 0-65535 if
481  *		  present.
482  *
483  *   input: char **: pointer to string pointer
484  *	    int *: error return value
485  *  output: int: hardware type, or -1 for empty, or -2 for error.
486  */
487 
488 static int
489 get_hw_type(char **strp, int *ierrnop)
490 {
491 	char *str = *strp;
492 	ulong_t hwtype;
493 
494 	if (*str++ != ',') {
495 		*ierrnop = ITAB_BAD_NUMBER;
496 		return (-2);
497 	}
498 	if (*str == ',' || *str == '\0') {
499 		*strp = str;
500 		return (-1);
501 	}
502 	hwtype = strtoul(str, strp, 0);
503 	if (errno != 0 || *strp == str || hwtype > 65535) {
504 		*ierrnop = ITAB_BAD_NUMBER;
505 		return (-2);
506 	} else {
507 		return ((int)hwtype);
508 	}
509 }
510 
511 /*
512  * get_mac_addr(): interpret ",macaddr" in the input string, as part of a DUID.
513  *		   The 'macaddr' may be a hex string (in any standard format),
514  *		   or the name of a physical interface.  If an interface name
515  *		   is given, then the interface type is extracted as well.
516  *
517  *   input: const char *: input string
518  *	    int *: error return value
519  *	    uint16_t *: hardware type output (network byte order)
520  *	    int: hardware type input; -1 for empty
521  *	    uchar_t *: output buffer for MAC address
522  *  output: int: length of MAC address, or -1 for error
523  */
524 
525 static int
526 get_mac_addr(const char *str, int *ierrnop, uint16_t *hwret, int hwtype,
527     uchar_t *outbuf)
528 {
529 	int maclen;
530 	int dig, val;
531 	dlpi_handle_t dh;
532 	dlpi_info_t dlinfo;
533 	char chr;
534 
535 	if (*str != '\0') {
536 		if (*str++ != ',')
537 			goto failed;
538 		if (dlpi_open(str, &dh, 0) != DLPI_SUCCESS) {
539 			maclen = 0;
540 			dig = val = 0;
541 			/*
542 			 * Allow MAC addresses with separators matching regexp
543 			 * (:|-| *).
544 			 */
545 			while ((chr = *str++) != '\0') {
546 				if (isdigit(chr)) {
547 					val = (val << 4) + chr - '0';
548 				} else if (isxdigit(chr)) {
549 					val = (val << 4) + chr -
550 					    (isupper(chr) ? 'A' : 'a') + 10;
551 				} else if (isspace(chr) && dig == 0) {
552 					continue;
553 				} else if (chr == ':' || chr == '-' ||
554 				    isspace(chr)) {
555 					dig = 1;
556 				} else {
557 					goto failed;
558 				}
559 				if (++dig == 2) {
560 					*outbuf++ = val;
561 					maclen++;
562 					dig = val = 0;
563 				}
564 			}
565 		} else {
566 			if (dlpi_info(dh, &dlinfo, 0) != DLPI_SUCCESS) {
567 				dlpi_close(dh);
568 				goto failed;
569 			}
570 			maclen = dlinfo.di_physaddrlen;
571 			(void) memcpy(outbuf, dlinfo.di_physaddr, maclen);
572 			dlpi_close(dh);
573 			if (hwtype == -1)
574 				hwtype = dlpi_to_arp(dlinfo.di_mactype);
575 		}
576 	}
577 	if (hwtype == -1)
578 		goto failed;
579 	*hwret = htons(hwtype);
580 	return (maclen);
581 
582 failed:
583 	*ierrnop = ITAB_BAD_NUMBER;
584 	return (-1);
585 }
586 
587 /*
588  * inittab_encode_e(): converts a string representation of a given datatype into
589  *		     binary; used for encoding ascii values into a form that
590  *		     can be put in DHCP packets to be sent on the wire.
591  *
592  *   input: const dhcp_symbol_t *: the entry describing the value option
593  *	    const char *: the value to convert
594  *	    uint16_t *: set to the length of the binary data returned
595  *	    boolean_t: if false, return a full DHCP option
596  *	    int *: error return value
597  *  output: uchar_t *: a dynamically allocated byte array with converted data
598  */
599 
600 uchar_t *
601 inittab_encode_e(const dhcp_symbol_t *ie, const char *value, uint16_t *lengthp,
602     boolean_t just_payload, int *ierrnop)
603 {
604 	int		hlen = 0;
605 	uint16_t	length;
606 	uchar_t		n_entries = 0;
607 	const char	*valuep;
608 	char		*currp;
609 	uchar_t		*result = NULL;
610 	uchar_t		*optstart;
611 	unsigned int	i;
612 	uint8_t		type_size = inittab_type_to_size(ie);
613 	boolean_t	is_signed;
614 	uint_t		vallen, reslen;
615 	dhcpv6_option_t	*d6o;
616 	int		type;
617 	char		*cp2;
618 
619 	*ierrnop = 0;
620 	if (type_size == 0) {
621 		*ierrnop = ITAB_SYNTAX_ERROR;
622 		return (NULL);
623 	}
624 
625 	switch (ie->ds_type) {
626 	case DSYM_ASCII:
627 		n_entries = strlen(value);		/* no NUL */
628 		break;
629 
630 	case DSYM_OCTET:
631 		vallen = strlen(value);
632 		n_entries = vallen / 2;
633 		n_entries += vallen % 2;
634 		break;
635 
636 	case DSYM_DOMAIN:
637 		/*
638 		 * Maximum (worst-case) encoded length is one byte more than
639 		 * the number of characters on input.
640 		 */
641 		n_entries = strlen(value) + 1;
642 		break;
643 
644 	case DSYM_DUID:
645 		/* Worst case is ":::::" */
646 		n_entries = strlen(value);
647 		if (n_entries < DLPI_PHYSADDR_MAX)
648 			n_entries = DLPI_PHYSADDR_MAX;
649 		n_entries += sizeof (duid_llt_t);
650 		break;
651 
652 	default:
653 		/*
654 		 * figure out the number of entries by counting the spaces
655 		 * in the value string
656 		 */
657 		for (valuep = value; valuep++ != NULL; n_entries++)
658 			valuep = strchr(valuep, ' ');
659 		break;
660 	}
661 
662 	/*
663 	 * if we're gonna return a complete option, then include the
664 	 * option length and code in the size of the packet we allocate
665 	 */
666 	if (!just_payload)
667 		hlen = ie->ds_dhcpv6 ? sizeof (*d6o) : 2;
668 
669 	length = n_entries * type_size;
670 	if (hlen + length > 0)
671 		result = malloc(hlen + length);
672 
673 	if ((optstart = result) != NULL && !just_payload)
674 		optstart += hlen;
675 
676 	switch (ie->ds_type) {
677 
678 	case DSYM_ASCII:
679 
680 		if (optstart == NULL) {
681 			*ierrnop = ITAB_NOMEM;
682 			return (NULL);
683 		}
684 
685 		(void) memcpy(optstart, value, length);
686 		break;
687 
688 	case DSYM_DOMAIN:
689 		if (optstart == NULL) {
690 			*ierrnop = ITAB_NOMEM;
691 			return (NULL);
692 		}
693 
694 		/*
695 		 * Note that this encoder always presents the trailing 0-octet
696 		 * when dealing with a list.  This means that you can't have
697 		 * non-fully-qualified members anywhere but at the end of a
698 		 * list (or as the only member of the list).
699 		 */
700 		valuep = value;
701 		while (*valuep != '\0') {
702 			int dig, val, inchr;
703 			boolean_t escape;
704 			uchar_t *flen;
705 
706 			/*
707 			 * Skip over whitespace that delimits list members.
708 			 */
709 			if (isascii(*valuep) && isspace(*valuep)) {
710 				valuep++;
711 				continue;
712 			}
713 			dig = val = 0;
714 			escape = B_FALSE;
715 			flen = optstart++;
716 			while ((inchr = *valuep) != '\0') {
717 				valuep++;
718 				/*
719 				 * Just copy non-ASCII text directly to the
720 				 * output string.  This simplifies the use of
721 				 * other ctype macros below, as, unlike the
722 				 * special isascii function, they don't handle
723 				 * non-ASCII.
724 				 */
725 				if (!isascii(inchr)) {
726 					escape = B_FALSE;
727 					*optstart++ = inchr;
728 					continue;
729 				}
730 				if (escape) {
731 					/*
732 					 * Handle any of \D, \DD, or \DDD for
733 					 * a digit escape.
734 					 */
735 					if (isdigit(inchr)) {
736 						val = val * 10 + inchr - '0';
737 						if (++dig == 3) {
738 							*optstart++ = val;
739 							dig = val = 0;
740 							escape = B_FALSE;
741 						}
742 						continue;
743 					} else if (dig > 0) {
744 						/*
745 						 * User terminated \D or \DD
746 						 * with non-digit.  An error,
747 						 * but we can assume he means
748 						 * to treat as \00D or \0DD.
749 						 */
750 						*optstart++ = val;
751 						dig = val = 0;
752 					}
753 					/* Fall through and copy character */
754 					escape = B_FALSE;
755 				} else if (inchr == '\\') {
756 					escape = B_TRUE;
757 					continue;
758 				} else if (inchr == '.') {
759 					/*
760 					 * End of component.  Write the length
761 					 * prefix.  If the component is zero
762 					 * length (i.e., ".."), the just omit
763 					 * it.
764 					 */
765 					*flen = (optstart - flen) - 1;
766 					if (*flen > 0)
767 						flen = optstart++;
768 					continue;
769 				} else if (isspace(inchr)) {
770 					/*
771 					 * Unescaped space; end of domain name
772 					 * in list.
773 					 */
774 					break;
775 				}
776 				*optstart++ = inchr;
777 			}
778 			/*
779 			 * Handle trailing escape sequence.  If string ends
780 			 * with \, then assume user wants \ at end of encoded
781 			 * string.  If it ends with \D or \DD, assume \00D or
782 			 * \0DD.
783 			 */
784 			if (escape)
785 				*optstart++ = dig > 0 ? val : '\\';
786 			*flen = (optstart - flen) - 1;
787 			/*
788 			 * If user specified FQDN with trailing '.', then above
789 			 * will result in zero for the last component length.
790 			 * We're done, and optstart already points to the start
791 			 * of the next in list.  Otherwise, we need to write a
792 			 * single zero byte to end the entry, if there are more
793 			 * entries that will be decoded.
794 			 */
795 			while (isascii(*valuep) && isspace(*valuep))
796 				valuep++;
797 			if (*flen > 0 && *valuep != '\0')
798 				*optstart++ = '\0';
799 		}
800 		length = (optstart - result) - hlen;
801 		break;
802 
803 	case DSYM_DUID:
804 		if (optstart == NULL) {
805 			*ierrnop = ITAB_NOMEM;
806 			return (NULL);
807 		}
808 
809 		errno = 0;
810 		type = strtoul(value, &currp, 0);
811 		if (errno != 0 || value == currp || type > 65535 ||
812 		    (*currp != ',' && *currp != '\0')) {
813 			free(result);
814 			*ierrnop = ITAB_BAD_NUMBER;
815 			return (NULL);
816 		}
817 		switch (type) {
818 		case DHCPV6_DUID_LLT: {
819 			duid_llt_t dllt;
820 			int hwtype;
821 			ulong_t tstamp;
822 			int maclen;
823 
824 			if ((hwtype = get_hw_type(&currp, ierrnop)) == -2) {
825 				free(result);
826 				return (NULL);
827 			}
828 			if (*currp++ != ',') {
829 				free(result);
830 				*ierrnop = ITAB_BAD_NUMBER;
831 				return (NULL);
832 			}
833 			if (*currp == ',' || *currp == '\0') {
834 				tstamp = time(NULL) - DUID_TIME_BASE;
835 			} else {
836 				tstamp = strtoul(currp, &cp2, 0);
837 				if (errno != 0 || currp == cp2) {
838 					free(result);
839 					*ierrnop = ITAB_BAD_NUMBER;
840 					return (NULL);
841 				}
842 				currp = cp2;
843 			}
844 			maclen = get_mac_addr(currp, ierrnop,
845 			    &dllt.dllt_hwtype, hwtype,
846 			    optstart + sizeof (dllt));
847 			if (maclen == -1) {
848 				free(result);
849 				return (NULL);
850 			}
851 			dllt.dllt_dutype = htons(type);
852 			dllt.dllt_time = htonl(tstamp);
853 			(void) memcpy(optstart, &dllt, sizeof (dllt));
854 			length = maclen + sizeof (dllt);
855 			break;
856 		}
857 		case DHCPV6_DUID_EN: {
858 			duid_en_t den;
859 			ulong_t enterp;
860 
861 			if (*currp++ != ',') {
862 				free(result);
863 				*ierrnop = ITAB_BAD_NUMBER;
864 				return (NULL);
865 			}
866 			enterp = strtoul(currp, &cp2, 0);
867 			DHCPV6_SET_ENTNUM(&den, enterp);
868 			if (errno != 0 || currp == cp2 ||
869 			    enterp != DHCPV6_GET_ENTNUM(&den) ||
870 			    (*cp2 != ',' && *cp2 != '\0')) {
871 				free(result);
872 				*ierrnop = ITAB_BAD_NUMBER;
873 				return (NULL);
874 			}
875 			if (*cp2 == ',')
876 				cp2++;
877 			vallen = strlen(cp2);
878 			reslen = (vallen + 1) / 2;
879 			if (hexascii_to_octet(cp2, vallen,
880 			    optstart + sizeof (den), &reslen) != 0) {
881 				free(result);
882 				*ierrnop = ITAB_BAD_NUMBER;
883 				return (NULL);
884 			}
885 			den.den_dutype = htons(type);
886 			(void) memcpy(optstart, &den, sizeof (den));
887 			length = reslen + sizeof (den);
888 			break;
889 		}
890 		case DHCPV6_DUID_LL: {
891 			duid_ll_t dll;
892 			int hwtype;
893 			int maclen;
894 
895 			if ((hwtype = get_hw_type(&currp, ierrnop)) == -2) {
896 				free(result);
897 				return (NULL);
898 			}
899 			maclen = get_mac_addr(currp, ierrnop, &dll.dll_hwtype,
900 			    hwtype, optstart + sizeof (dll));
901 			if (maclen == -1) {
902 				free(result);
903 				return (NULL);
904 			}
905 			dll.dll_dutype = htons(type);
906 			(void) memcpy(optstart, &dll, sizeof (dll));
907 			length = maclen + sizeof (dll);
908 			break;
909 		}
910 		default:
911 			if (*currp == ',')
912 				currp++;
913 			vallen = strlen(currp);
914 			reslen = (vallen + 1) / 2;
915 			if (hexascii_to_octet(currp, vallen, optstart + 2,
916 			    &reslen) != 0) {
917 				free(result);
918 				*ierrnop = ITAB_BAD_NUMBER;
919 				return (NULL);
920 			}
921 			optstart[0] = type >> 8;
922 			optstart[1] = type;
923 			length = reslen + 2;
924 			break;
925 		}
926 		break;
927 
928 	case DSYM_OCTET:
929 
930 		if (optstart == NULL) {
931 			*ierrnop = ITAB_BAD_OCTET;
932 			return (NULL);
933 		}
934 
935 		reslen = length;
936 		/* Call libinetutil function to decode */
937 		if (hexascii_to_octet(value, vallen, optstart, &reslen) != 0) {
938 			free(result);
939 			*ierrnop = ITAB_BAD_OCTET;
940 			return (NULL);
941 		}
942 		break;
943 
944 	case DSYM_IP:
945 	case DSYM_IPV6:
946 
947 		if (optstart == NULL) {
948 			*ierrnop = ITAB_BAD_IPADDR;
949 			return (NULL);
950 		}
951 		if (n_entries % ie->ds_gran != 0) {
952 			*ierrnop = ITAB_BAD_GRAN;
953 			inittab_msg("inittab_encode: number of entries "
954 			    "not compatible with option granularity");
955 			free(result);
956 			return (NULL);
957 		}
958 
959 		for (valuep = value, i = 0; i < n_entries; i++, valuep++) {
960 
961 			currp = strchr(valuep, ' ');
962 			if (currp != NULL)
963 				*currp = '\0';
964 			if (inet_pton(ie->ds_type == DSYM_IP ? AF_INET :
965 			    AF_INET6, valuep, optstart) != 1) {
966 				*ierrnop = ITAB_BAD_IPADDR;
967 				inittab_msg("inittab_encode: bogus ip address");
968 				free(result);
969 				return (NULL);
970 			}
971 
972 			valuep = currp;
973 			if (valuep == NULL) {
974 				if (i < (n_entries - 1)) {
975 					*ierrnop = ITAB_NOT_ENOUGH_IP;
976 					inittab_msg("inittab_encode: too few "
977 					    "ip addresses");
978 					free(result);
979 					return (NULL);
980 				}
981 				break;
982 			}
983 			optstart += type_size;
984 		}
985 		break;
986 
987 	case DSYM_NUMBER:				/* FALLTHRU */
988 	case DSYM_UNUMBER8:				/* FALLTHRU */
989 	case DSYM_SNUMBER8:				/* FALLTHRU */
990 	case DSYM_UNUMBER16:				/* FALLTHRU */
991 	case DSYM_SNUMBER16:				/* FALLTHRU */
992 	case DSYM_UNUMBER24:				/* FALLTHRU */
993 	case DSYM_UNUMBER32:				/* FALLTHRU */
994 	case DSYM_SNUMBER32:				/* FALLTHRU */
995 	case DSYM_UNUMBER64:				/* FALLTHRU */
996 	case DSYM_SNUMBER64:
997 
998 		if (optstart == NULL) {
999 			*ierrnop = ITAB_BAD_NUMBER;
1000 			return (NULL);
1001 		}
1002 
1003 		is_signed = (ie->ds_type == DSYM_SNUMBER64 ||
1004 		    ie->ds_type == DSYM_SNUMBER32 ||
1005 		    ie->ds_type == DSYM_SNUMBER16 ||
1006 		    ie->ds_type == DSYM_SNUMBER8);
1007 
1008 		if (encode_number(n_entries, type_size, is_signed, 0, value,
1009 		    optstart, ierrnop) == B_FALSE) {
1010 			free(result);
1011 			return (NULL);
1012 		}
1013 		break;
1014 
1015 	default:
1016 		if (ie->ds_type == DSYM_BOOL)
1017 			*ierrnop = ITAB_BAD_BOOLEAN;
1018 		else
1019 			*ierrnop = ITAB_SYNTAX_ERROR;
1020 
1021 		inittab_msg("inittab_encode: unsupported type `%d'",
1022 		    ie->ds_type);
1023 
1024 		free(result);
1025 		return (NULL);
1026 	}
1027 
1028 	/*
1029 	 * if just_payload is false, then we need to add the option
1030 	 * code and length fields in.
1031 	 */
1032 	if (!just_payload) {
1033 		if (ie->ds_dhcpv6) {
1034 			/* LINTED: alignment */
1035 			d6o = (dhcpv6_option_t *)result;
1036 			d6o->d6o_code = htons(ie->ds_code);
1037 			d6o->d6o_len = htons(length);
1038 		} else {
1039 			result[0] = ie->ds_code;
1040 			result[1] = length;
1041 		}
1042 	}
1043 
1044 	if (lengthp != NULL)
1045 		*lengthp = length + hlen;
1046 
1047 	return (result);
1048 }
1049 
1050 /*
1051  * inittab_decode_e(): converts a binary representation of a given datatype into
1052  *		     a string; used for decoding DHCP options in a packet off
1053  *		     the wire into ascii
1054  *
1055  *   input: dhcp_symbol_t *: the entry describing the payload option
1056  *	    uchar_t *: the payload to convert
1057  *	    uint16_t: the payload length (only used if just_payload is true)
1058  *	    boolean_t: if false, payload is assumed to be a DHCP option
1059  *	    int *: set to extended error code if error occurs.
1060  *  output: char *: a dynamically allocated string containing the converted data
1061  */
1062 
1063 char *
1064 inittab_decode_e(const dhcp_symbol_t *ie, const uchar_t *payload,
1065     uint16_t length, boolean_t just_payload, int *ierrnop)
1066 {
1067 	char		*resultp, *result = NULL;
1068 	uint_t		n_entries;
1069 	struct in_addr	in_addr;
1070 	in6_addr_t	in6_addr;
1071 	uint8_t		type_size = inittab_type_to_size(ie);
1072 	boolean_t	is_signed;
1073 	int		type;
1074 
1075 	*ierrnop = 0;
1076 	if (type_size == 0) {
1077 		*ierrnop = ITAB_SYNTAX_ERROR;
1078 		return (NULL);
1079 	}
1080 
1081 	if (!just_payload) {
1082 		if (ie->ds_dhcpv6) {
1083 			dhcpv6_option_t d6o;
1084 
1085 			(void) memcpy(&d6o, payload, sizeof (d6o));
1086 			length = ntohs(d6o.d6o_len);
1087 			payload += sizeof (d6o);
1088 		} else {
1089 			length = payload[1];
1090 			payload += 2;
1091 		}
1092 	}
1093 
1094 	/*
1095 	 * figure out the number of elements to convert.  note that
1096 	 * for ds_type NUMBER, the granularity is really 1 since the
1097 	 * value of ds_gran is the number of bytes in the number.
1098 	 */
1099 	if (ie->ds_type == DSYM_NUMBER)
1100 		n_entries = MIN(ie->ds_max, length / type_size);
1101 	else
1102 		n_entries = MIN(ie->ds_max * ie->ds_gran, length / type_size);
1103 
1104 	if (n_entries == 0)
1105 		n_entries = length / type_size;
1106 
1107 	if ((length % type_size) != 0) {
1108 		inittab_msg("inittab_decode: length of string not compatible "
1109 		    "with option type `%i'", ie->ds_type);
1110 		*ierrnop = ITAB_BAD_STRING;
1111 		return (NULL);
1112 	}
1113 
1114 	switch (ie->ds_type) {
1115 
1116 	case DSYM_ASCII:
1117 
1118 		result = malloc(n_entries + 1);
1119 		if (result == NULL) {
1120 			*ierrnop = ITAB_NOMEM;
1121 			return (NULL);
1122 		}
1123 
1124 		(void) memcpy(result, payload, n_entries);
1125 		result[n_entries] = '\0';
1126 		break;
1127 
1128 	case DSYM_DOMAIN:
1129 
1130 		/*
1131 		 * A valid, decoded RFC 1035 domain string or sequence of
1132 		 * strings is always the same size as the encoded form, but we
1133 		 * allow for RFC 1035 \DDD and \\ and \. escaping.
1134 		 *
1135 		 * Decoding stops at the end of the input or the first coding
1136 		 * violation.  Coding violations result in discarding the
1137 		 * offending list entry entirely.  Note that we ignore the 255
1138 		 * character overall limit on domain names.
1139 		 */
1140 		if ((result = malloc(4 * length + 1)) == NULL) {
1141 			*ierrnop = ITAB_NOMEM;
1142 			return (NULL);
1143 		}
1144 		resultp = result;
1145 		while (length > 0) {
1146 			char *dstart;
1147 			int slen;
1148 
1149 			dstart = resultp;
1150 			while (length > 0) {
1151 				slen = *payload++;
1152 				length--;
1153 				/* Upper two bits of length must be zero */
1154 				if ((slen & 0xc0) != 0 || slen > length) {
1155 					length = 0;
1156 					resultp = dstart;
1157 					break;
1158 				}
1159 				if (resultp != dstart)
1160 					*resultp++ = '.';
1161 				if (slen == 0)
1162 					break;
1163 				length -= slen;
1164 				while (slen > 0) {
1165 					if (!isascii(*payload) ||
1166 					    !isgraph(*payload)) {
1167 						(void) snprintf(resultp, 5,
1168 						    "\\%03d",
1169 						    *(unsigned char *)payload);
1170 						resultp += 4;
1171 						payload++;
1172 					} else {
1173 						if (*payload == '.' ||
1174 						    *payload == '\\')
1175 							*resultp++ = '\\';
1176 						*resultp++ = *payload++;
1177 					}
1178 					slen--;
1179 				}
1180 			}
1181 			if (resultp != dstart && length > 0)
1182 				*resultp++ = ' ';
1183 		}
1184 		*resultp = '\0';
1185 		break;
1186 
1187 	case DSYM_DUID:
1188 
1189 		/*
1190 		 * First, determine the type of DUID.  We need at least two
1191 		 * octets worth of data to grab the type code.  Once we have
1192 		 * that, the number of octets required for representation
1193 		 * depends on the type.
1194 		 */
1195 
1196 		if (length < 2) {
1197 			*ierrnop = ITAB_BAD_GRAN;
1198 			return (NULL);
1199 		}
1200 		type = (payload[0] << 8) + payload[1];
1201 		switch (type) {
1202 		case DHCPV6_DUID_LLT: {
1203 			duid_llt_t dllt;
1204 
1205 			if (length < sizeof (dllt)) {
1206 				*ierrnop = ITAB_BAD_GRAN;
1207 				return (NULL);
1208 			}
1209 			(void) memcpy(&dllt, payload, sizeof (dllt));
1210 			payload += sizeof (dllt);
1211 			length -= sizeof (dllt);
1212 			n_entries = sizeof ("1,65535,4294967295,") +
1213 			    length * 3;
1214 			if ((result = malloc(n_entries)) == NULL) {
1215 				*ierrnop = ITAB_NOMEM;
1216 				return (NULL);
1217 			}
1218 			(void) snprintf(result, n_entries, "%d,%u,%u,", type,
1219 			    ntohs(dllt.dllt_hwtype), ntohl(dllt.dllt_time));
1220 			break;
1221 		}
1222 		case DHCPV6_DUID_EN: {
1223 			duid_en_t den;
1224 
1225 			if (length < sizeof (den)) {
1226 				*ierrnop = ITAB_BAD_GRAN;
1227 				return (NULL);
1228 			}
1229 			(void) memcpy(&den, payload, sizeof (den));
1230 			payload += sizeof (den);
1231 			length -= sizeof (den);
1232 			n_entries = sizeof ("2,4294967295,") + length * 2;
1233 			if ((result = malloc(n_entries)) == NULL) {
1234 				*ierrnop = ITAB_NOMEM;
1235 				return (NULL);
1236 			}
1237 			(void) snprintf(result, n_entries, "%d,%u,", type,
1238 			    DHCPV6_GET_ENTNUM(&den));
1239 			break;
1240 		}
1241 		case DHCPV6_DUID_LL: {
1242 			duid_ll_t dll;
1243 
1244 			if (length < sizeof (dll)) {
1245 				*ierrnop = ITAB_BAD_GRAN;
1246 				return (NULL);
1247 			}
1248 			(void) memcpy(&dll, payload, sizeof (dll));
1249 			payload += sizeof (dll);
1250 			length -= sizeof (dll);
1251 			n_entries = sizeof ("3,65535,") + length * 3;
1252 			if ((result = malloc(n_entries)) == NULL) {
1253 				*ierrnop = ITAB_NOMEM;
1254 				return (NULL);
1255 			}
1256 			(void) snprintf(result, n_entries, "%d,%u,", type,
1257 			    ntohs(dll.dll_hwtype));
1258 			break;
1259 		}
1260 		default:
1261 			n_entries = sizeof ("0,") + length * 2;
1262 			if ((result = malloc(n_entries)) == NULL) {
1263 				*ierrnop = ITAB_NOMEM;
1264 				return (NULL);
1265 			}
1266 			(void) snprintf(result, n_entries, "%d,", type);
1267 			break;
1268 		}
1269 		resultp = result + strlen(result);
1270 		n_entries -= strlen(result);
1271 		if (type == DHCPV6_DUID_LLT || type == DHCPV6_DUID_LL) {
1272 			if (length > 0) {
1273 				resultp += snprintf(resultp, 3, "%02X",
1274 				    *payload++);
1275 				length--;
1276 			}
1277 			while (length-- > 0) {
1278 				resultp += snprintf(resultp, 4, ":%02X",
1279 				    *payload++);
1280 			}
1281 		} else {
1282 			while (length-- > 0) {
1283 				resultp += snprintf(resultp, 3, "%02X",
1284 				    *payload++);
1285 			}
1286 		}
1287 		break;
1288 
1289 	case DSYM_OCTET:
1290 
1291 		result = malloc(n_entries * (sizeof ("0xNN") + 1));
1292 		if (result == NULL) {
1293 			*ierrnop = ITAB_NOMEM;
1294 			return (NULL);
1295 		}
1296 
1297 		result[0] = '\0';
1298 		resultp = result;
1299 		if (n_entries > 0) {
1300 			resultp += sprintf(resultp, "0x%02X", *payload++);
1301 			n_entries--;
1302 		}
1303 		while (n_entries-- > 0)
1304 			resultp += sprintf(resultp, " 0x%02X", *payload++);
1305 
1306 		break;
1307 
1308 	case DSYM_IP:
1309 	case DSYM_IPV6:
1310 		if ((length / type_size) % ie->ds_gran != 0) {
1311 			*ierrnop = ITAB_BAD_GRAN;
1312 			inittab_msg("inittab_decode: number of entries "
1313 			    "not compatible with option granularity");
1314 			return (NULL);
1315 		}
1316 
1317 		result = malloc(n_entries * (ie->ds_type == DSYM_IP ?
1318 		    INET_ADDRSTRLEN : INET6_ADDRSTRLEN));
1319 		if (result == NULL) {
1320 			*ierrnop = ITAB_NOMEM;
1321 			return (NULL);
1322 		}
1323 
1324 		for (resultp = result; n_entries != 0; n_entries--) {
1325 			if (ie->ds_type == DSYM_IP) {
1326 				(void) memcpy(&in_addr.s_addr, payload,
1327 				    sizeof (ipaddr_t));
1328 				(void) strcpy(resultp, inet_ntoa(in_addr));
1329 			} else {
1330 				(void) memcpy(&in6_addr, payload,
1331 				    sizeof (in6_addr));
1332 				(void) inet_ntop(AF_INET6, &in6_addr, resultp,
1333 				    INET6_ADDRSTRLEN);
1334 			}
1335 			resultp += strlen(resultp);
1336 			if (n_entries > 1)
1337 				*resultp++ = ' ';
1338 			payload += type_size;
1339 		}
1340 		*resultp = '\0';
1341 		break;
1342 
1343 	case DSYM_NUMBER:				/* FALLTHRU */
1344 	case DSYM_UNUMBER8:				/* FALLTHRU */
1345 	case DSYM_SNUMBER8:				/* FALLTHRU */
1346 	case DSYM_UNUMBER16:				/* FALLTHRU */
1347 	case DSYM_SNUMBER16:				/* FALLTHRU */
1348 	case DSYM_UNUMBER32:				/* FALLTHRU */
1349 	case DSYM_SNUMBER32:				/* FALLTHRU */
1350 	case DSYM_UNUMBER64:				/* FALLTHRU */
1351 	case DSYM_SNUMBER64:
1352 
1353 		is_signed = (ie->ds_type == DSYM_SNUMBER64 ||
1354 		    ie->ds_type == DSYM_SNUMBER32 ||
1355 		    ie->ds_type == DSYM_SNUMBER16 ||
1356 		    ie->ds_type == DSYM_SNUMBER8);
1357 
1358 		result = malloc(n_entries * ITAB_MAX_NUMBER_LEN);
1359 		if (result == NULL) {
1360 			*ierrnop = ITAB_NOMEM;
1361 			return (NULL);
1362 		}
1363 
1364 		if (decode_number(n_entries, type_size, is_signed, ie->ds_gran,
1365 		    payload, result, ierrnop) == B_FALSE) {
1366 			free(result);
1367 			return (NULL);
1368 		}
1369 		break;
1370 
1371 	default:
1372 		inittab_msg("inittab_decode: unsupported type `%d'",
1373 		    ie->ds_type);
1374 		break;
1375 	}
1376 
1377 	return (result);
1378 }
1379 
1380 /*
1381  * inittab_encode(): converts a string representation of a given datatype into
1382  *		     binary; used for encoding ascii values into a form that
1383  *		     can be put in DHCP packets to be sent on the wire.
1384  *
1385  *   input: dhcp_symbol_t *: the entry describing the value option
1386  *	    const char *: the value to convert
1387  *	    uint16_t *: set to the length of the binary data returned
1388  *	    boolean_t: if false, return a full DHCP option
1389  *  output: uchar_t *: a dynamically allocated byte array with converted data
1390  */
1391 
1392 uchar_t *
1393 inittab_encode(const dhcp_symbol_t *ie, const char *value, uint16_t *lengthp,
1394     boolean_t just_payload)
1395 {
1396 	int ierrno;
1397 
1398 	return (inittab_encode_e(ie, value, lengthp, just_payload, &ierrno));
1399 }
1400 
1401 /*
1402  * inittab_decode(): converts a binary representation of a given datatype into
1403  *		     a string; used for decoding DHCP options in a packet off
1404  *		     the wire into ascii
1405  *
1406  *   input: dhcp_symbol_t *: the entry describing the payload option
1407  *	    uchar_t *: the payload to convert
1408  *	    uint16_t: the payload length (only used if just_payload is true)
1409  *	    boolean_t: if false, payload is assumed to be a DHCP option
1410  *  output: char *: a dynamically allocated string containing the converted data
1411  */
1412 
1413 char *
1414 inittab_decode(const dhcp_symbol_t *ie, const uchar_t *payload, uint16_t length,
1415     boolean_t just_payload)
1416 {
1417 	int ierrno;
1418 
1419 	return (inittab_decode_e(ie, payload, length, just_payload, &ierrno));
1420 }
1421 
1422 /*
1423  * inittab_msg(): prints diagnostic messages if INITTAB_DEBUG is set
1424  *
1425  *	    const char *: a printf-like format string
1426  *	    ...: arguments to the format string
1427  *  output: void
1428  */
1429 
1430 /*PRINTFLIKE1*/
1431 static void
1432 inittab_msg(const char *fmt, ...)
1433 {
1434 	enum { INITTAB_MSG_CHECK, INITTAB_MSG_RETURN, INITTAB_MSG_OUTPUT };
1435 
1436 	va_list		ap;
1437 	char		buf[512];
1438 	static int	action = INITTAB_MSG_CHECK;
1439 
1440 	/*
1441 	 * check DHCP_INITTAB_DEBUG the first time in; thereafter, use
1442 	 * the the cached result (stored in `action').
1443 	 */
1444 	switch (action) {
1445 
1446 	case INITTAB_MSG_CHECK:
1447 
1448 		if (getenv("DHCP_INITTAB_DEBUG") == NULL) {
1449 			action = INITTAB_MSG_RETURN;
1450 			return;
1451 		}
1452 
1453 		action = INITTAB_MSG_OUTPUT;
1454 
1455 		/* FALLTHRU into INITTAB_MSG_OUTPUT */
1456 
1457 	case INITTAB_MSG_OUTPUT:
1458 
1459 		va_start(ap, fmt);
1460 
1461 		(void) snprintf(buf, sizeof (buf), "inittab: %s\n", fmt);
1462 		(void) vfprintf(stderr, buf, ap);
1463 
1464 		va_end(ap);
1465 		break;
1466 
1467 	case INITTAB_MSG_RETURN:
1468 
1469 		return;
1470 	}
1471 }
1472 
1473 /*
1474  * decode_number(): decodes a sequence of numbers from binary into ascii;
1475  *		    binary is coming off of the network, so it is in nbo
1476  *
1477  *   input: uint8_t: the number of "granularity" numbers to decode
1478  *	    uint8_t: the length of each number
1479  *	    boolean_t: whether the numbers should be considered signed
1480  *	    uint8_t: the number of numbers per granularity
1481  *	    const uint8_t *: where to decode the numbers from
1482  *	    char *: where to decode the numbers to
1483  *  output: boolean_t: true on successful conversion, false on failure
1484  */
1485 
1486 static boolean_t
1487 decode_number(uint8_t n_entries, uint8_t size, boolean_t is_signed,
1488     uint8_t granularity, const uint8_t *from, char *to, int *ierrnop)
1489 {
1490 	uint16_t	uint16;
1491 	uint32_t	uint32;
1492 	uint64_t	uint64;
1493 
1494 	if (granularity != 0) {
1495 		if ((granularity % n_entries) != 0) {
1496 			inittab_msg("decode_number: number of entries "
1497 			    "not compatible with option granularity");
1498 			*ierrnop = ITAB_BAD_GRAN;
1499 			return (B_FALSE);
1500 		}
1501 	}
1502 
1503 	for (; n_entries != 0; n_entries--, from += size) {
1504 
1505 		switch (size) {
1506 
1507 		case 1:
1508 			to += sprintf(to, is_signed ? "%d" : "%u", *from);
1509 			break;
1510 
1511 		case 2:
1512 			(void) memcpy(&uint16, from, 2);
1513 			to += sprintf(to, is_signed ? "%hd" : "%hu",
1514 			    ntohs(uint16));
1515 			break;
1516 
1517 		case 3:
1518 			uint32 = 0;
1519 			(void) memcpy((uchar_t *)&uint32 + 1, from, 3);
1520 			to += sprintf(to, is_signed ? "%ld" : "%lu",
1521 			    ntohl(uint32));
1522 			break;
1523 
1524 		case 4:
1525 			(void) memcpy(&uint32, from, 4);
1526 			to += sprintf(to, is_signed ? "%ld" : "%lu",
1527 			    ntohl(uint32));
1528 			break;
1529 
1530 		case 8:
1531 			(void) memcpy(&uint64, from, 8);
1532 			to += sprintf(to, is_signed ? "%lld" : "%llu",
1533 			    dhcp_ntohll(uint64));
1534 			break;
1535 
1536 		default:
1537 			*ierrnop = ITAB_BAD_NUMBER;
1538 			inittab_msg("decode_number: unknown integer size `%d'",
1539 			    size);
1540 			return (B_FALSE);
1541 		}
1542 		if (n_entries > 0)
1543 			*to++ = ' ';
1544 	}
1545 
1546 	*to = '\0';
1547 	return (B_TRUE);
1548 }
1549 
1550 /*
1551  * encode_number(): encodes a sequence of numbers from ascii into binary;
1552  *		    number will end up on the wire so it needs to be in nbo
1553  *
1554  *   input: uint8_t: the number of "granularity" numbers to encode
1555  *	    uint8_t: the length of each number
1556  *	    boolean_t: whether the numbers should be considered signed
1557  *	    uint8_t: the number of numbers per granularity
1558  *	    const uint8_t *: where to encode the numbers from
1559  *	    char *: where to encode the numbers to
1560  *	    int *: set to extended error code if error occurs.
1561  *  output: boolean_t: true on successful conversion, false on failure
1562  */
1563 
1564 static boolean_t /* ARGSUSED */
1565 encode_number(uint8_t n_entries, uint8_t size, boolean_t is_signed,
1566     uint8_t granularity, const char *from, uint8_t *to, int *ierrnop)
1567 {
1568 	uint8_t		i;
1569 	uint16_t	uint16;
1570 	uint32_t	uint32;
1571 	uint64_t	uint64;
1572 	char		*endptr;
1573 
1574 	if (granularity != 0) {
1575 		if ((granularity % n_entries) != 0) {
1576 			*ierrnop = ITAB_BAD_GRAN;
1577 			inittab_msg("encode_number: number of entries "
1578 			    "not compatible with option granularity");
1579 			return (B_FALSE);
1580 		}
1581 	}
1582 
1583 	for (i = 0; i < n_entries; i++, from++, to += size) {
1584 
1585 		/*
1586 		 * totally obscure c factoid: it is legal to pass a
1587 		 * string representing a negative number to strtoul().
1588 		 * in this case, strtoul() will return an unsigned
1589 		 * long that if cast to a long, would represent the
1590 		 * negative number.  we take advantage of this to
1591 		 * cut down on code here.
1592 		 */
1593 
1594 		errno = 0;
1595 		switch (size) {
1596 
1597 		case 1:
1598 			*to = strtoul(from, &endptr, 0);
1599 			if (errno != 0 || from == endptr) {
1600 				goto error;
1601 			}
1602 			break;
1603 
1604 		case 2:
1605 			uint16 = htons(strtoul(from, &endptr, 0));
1606 			if (errno != 0 || from == endptr) {
1607 				goto error;
1608 			}
1609 			(void) memcpy(to, &uint16, 2);
1610 			break;
1611 
1612 		case 3:
1613 			uint32 = htonl(strtoul(from, &endptr, 0));
1614 			if (errno != 0 || from == endptr) {
1615 				goto error;
1616 			}
1617 			(void) memcpy(to, (uchar_t *)&uint32 + 1, 3);
1618 			break;
1619 
1620 		case 4:
1621 			uint32 = htonl(strtoul(from, &endptr, 0));
1622 			if (errno != 0 || from == endptr) {
1623 				goto error;
1624 			}
1625 			(void) memcpy(to, &uint32, 4);
1626 			break;
1627 
1628 		case 8:
1629 			uint64 = dhcp_htonll(strtoull(from, &endptr, 0));
1630 			if (errno != 0 || from == endptr) {
1631 				goto error;
1632 			}
1633 			(void) memcpy(to, &uint64, 8);
1634 			break;
1635 
1636 		default:
1637 			inittab_msg("encode_number: unsupported integer "
1638 			    "size `%d'", size);
1639 			return (B_FALSE);
1640 		}
1641 
1642 		from = strchr(from, ' ');
1643 		if (from == NULL)
1644 			break;
1645 	}
1646 
1647 	return (B_TRUE);
1648 
1649 error:
1650 	*ierrnop = ITAB_BAD_NUMBER;
1651 	inittab_msg("encode_number: cannot convert to integer");
1652 	return (B_FALSE);
1653 }
1654 
1655 /*
1656  * inittab_type_to_size(): given an inittab entry, returns size of one entry of
1657  *		      its type
1658  *
1659  *   input: dhcp_symbol_t *: an entry of the given type
1660  *  output: uint8_t: the size in bytes of an entry of that type
1661  */
1662 
1663 uint8_t
1664 inittab_type_to_size(const dhcp_symbol_t *ie)
1665 {
1666 	switch (ie->ds_type) {
1667 
1668 	case DSYM_DUID:
1669 	case DSYM_DOMAIN:
1670 	case DSYM_ASCII:
1671 	case DSYM_OCTET:
1672 	case DSYM_SNUMBER8:
1673 	case DSYM_UNUMBER8:
1674 
1675 		return (1);
1676 
1677 	case DSYM_SNUMBER16:
1678 	case DSYM_UNUMBER16:
1679 
1680 		return (2);
1681 
1682 	case DSYM_UNUMBER24:
1683 
1684 		return (3);
1685 
1686 	case DSYM_SNUMBER32:
1687 	case DSYM_UNUMBER32:
1688 	case DSYM_IP:
1689 
1690 		return (4);
1691 
1692 	case DSYM_SNUMBER64:
1693 	case DSYM_UNUMBER64:
1694 
1695 		return (8);
1696 
1697 	case DSYM_NUMBER:
1698 
1699 		return (ie->ds_gran);
1700 
1701 	case DSYM_IPV6:
1702 
1703 		return (sizeof (in6_addr_t));
1704 	}
1705 
1706 	return (0);
1707 }
1708 
1709 /*
1710  * itabcode_to_dsymcode(): maps an inittab category code to its dsym
1711  *                         representation
1712  *
1713  *   input: uchar_t: the inittab category code
1714  *  output: dsym_category_t: the dsym category code
1715  */
1716 
1717 static dsym_category_t
1718 itabcode_to_dsymcode(uchar_t itabcode)
1719 {
1720 
1721 	unsigned int	i;
1722 
1723 	for (i = 0; i < ITAB_CAT_COUNT; i++)
1724 		if (category_map[i].cme_itabcode == itabcode)
1725 			return (category_map[i].cme_dsymcode);
1726 
1727 	return (DSYM_BAD_CAT);
1728 }
1729 
1730 /*
1731  * category_to_code(): maps a category name to its numeric representation
1732  *
1733  *   input: const char *: the category name
1734  *  output: uchar_t: its internal code (numeric representation)
1735  */
1736 
1737 static uchar_t
1738 category_to_code(const char *category)
1739 {
1740 	unsigned int	i;
1741 
1742 	for (i = 0; i < ITAB_CAT_COUNT; i++)
1743 		if (strcasecmp(category_map[i].cme_name, category) == 0)
1744 			return (category_map[i].cme_itabcode);
1745 
1746 	return (0);
1747 }
1748 
1749 /*
1750  * dhcp_htonll(): converts a 64-bit number from host to network byte order
1751  *
1752  *   input: uint64_t: the number to convert
1753  *  output: uint64_t: its value in network byte order
1754  */
1755 
1756 static uint64_t
1757 dhcp_htonll(uint64_t uint64_hbo)
1758 {
1759 	return (dhcp_ntohll(uint64_hbo));
1760 }
1761 
1762 /*
1763  * dhcp_ntohll(): converts a 64-bit number from network to host byte order
1764  *
1765  *   input: uint64_t: the number to convert
1766  *  output: uint64_t: its value in host byte order
1767  */
1768 
1769 static uint64_t
1770 dhcp_ntohll(uint64_t uint64_nbo)
1771 {
1772 #ifdef	_LITTLE_ENDIAN
1773 	return ((uint64_t)ntohl(uint64_nbo & 0xffffffff) << 32 |
1774 	    ntohl(uint64_nbo >> 32));
1775 #else
1776 	return (uint64_nbo);
1777 #endif
1778 }
1779 
1780 /*
1781  * our internal table of DHCP option values, used by inittab_verify()
1782  */
1783 static dhcp_symbol_t inittab_table[] =
1784 {
1785 { DSYM_INTERNAL,	1024,	"Hostname",	DSYM_BOOL,	0,	0 },
1786 { DSYM_INTERNAL,	1025,	"LeaseNeg",	DSYM_BOOL,	0,	0 },
1787 { DSYM_INTERNAL,	1026,	"EchoVC",	DSYM_BOOL,	0,	0 },
1788 { DSYM_INTERNAL,	1027,	"BootPath",	DSYM_ASCII,	1,	128 },
1789 { DSYM_FIELD,		0,	"Opcode",	DSYM_UNUMBER8,	1,	1 },
1790 { DSYM_FIELD,		1,	"Htype",	DSYM_UNUMBER8,	1,	1 },
1791 { DSYM_FIELD,		2,	"HLen",		DSYM_UNUMBER8,	1,	1 },
1792 { DSYM_FIELD,		3,	"Hops",		DSYM_UNUMBER8,	1,	1 },
1793 { DSYM_FIELD,		4,	"Xid",		DSYM_UNUMBER32,	1,	1 },
1794 { DSYM_FIELD,		8,	"Secs",		DSYM_UNUMBER16,	1,	1 },
1795 { DSYM_FIELD,		10,	"Flags",	DSYM_OCTET,	1,	2 },
1796 { DSYM_FIELD,		12,	"Ciaddr",	DSYM_IP,	1,	1 },
1797 { DSYM_FIELD,		16,	"Yiaddr",	DSYM_IP,	1,	1 },
1798 { DSYM_FIELD,		20,	"BootSrvA",	DSYM_IP,	1,	1 },
1799 { DSYM_FIELD,		24,	"Giaddr",	DSYM_IP,	1,	1 },
1800 { DSYM_FIELD,		28,	"Chaddr",	DSYM_OCTET, 	1,	16 },
1801 { DSYM_FIELD,		44,	"BootSrvN",	DSYM_ASCII,	1,	64 },
1802 { DSYM_FIELD,		108,	"BootFile",	DSYM_ASCII,	1,	128 },
1803 { DSYM_FIELD,		236,	"Magic",	DSYM_OCTET,	1,	4 },
1804 { DSYM_FIELD,		240,	"Options",	DSYM_OCTET,	1,	60 },
1805 { DSYM_STANDARD,	1,	"Subnet",	DSYM_IP,	1,	1 },
1806 { DSYM_STANDARD,	2,	"UTCoffst",	DSYM_SNUMBER32,	1,	1 },
1807 { DSYM_STANDARD,	3,	"Router",	DSYM_IP,	1,	0 },
1808 { DSYM_STANDARD,	4,	"Timeserv",	DSYM_IP,	1,	0 },
1809 { DSYM_STANDARD,	5,	"IEN116ns",	DSYM_IP,	1,	0 },
1810 { DSYM_STANDARD,	6,	"DNSserv",	DSYM_IP,	1,	0 },
1811 { DSYM_STANDARD,	7,	"Logserv",	DSYM_IP,	1,	0 },
1812 { DSYM_STANDARD,	8,	"Cookie",	DSYM_IP,	1,	0 },
1813 { DSYM_STANDARD,	9,	"Lprserv",	DSYM_IP,	1,	0 },
1814 { DSYM_STANDARD,	10,	"Impress",	DSYM_IP,	1,	0 },
1815 { DSYM_STANDARD,	11,	"Resource",	DSYM_IP,	1,	0 },
1816 { DSYM_STANDARD,	12,	"Hostname",	DSYM_ASCII,	1,	0 },
1817 { DSYM_STANDARD,	13,	"Bootsize",	DSYM_UNUMBER16,	1,	1 },
1818 { DSYM_STANDARD,	14,	"Dumpfile",	DSYM_ASCII,	1,	0 },
1819 { DSYM_STANDARD,	15,	"DNSdmain",	DSYM_ASCII,	1,	0 },
1820 { DSYM_STANDARD,	16,	"Swapserv",	DSYM_IP,	1,	1 },
1821 { DSYM_STANDARD,	17,	"Rootpath",	DSYM_ASCII,	1,	0 },
1822 { DSYM_STANDARD,	18,	"ExtendP",	DSYM_ASCII,	1,	0 },
1823 { DSYM_STANDARD,	19,	"IpFwdF",	DSYM_UNUMBER8,	1,	1 },
1824 { DSYM_STANDARD,	20,	"NLrouteF",	DSYM_UNUMBER8,	1,	1 },
1825 { DSYM_STANDARD,	21,	"PFilter",	DSYM_IP,	2,	0 },
1826 { DSYM_STANDARD,	22,	"MaxIpSiz",	DSYM_UNUMBER16,	1,	1 },
1827 { DSYM_STANDARD,	23,	"IpTTL",	DSYM_UNUMBER8,	1,	1 },
1828 { DSYM_STANDARD,	24,	"PathTO",	DSYM_UNUMBER32,	1,	1 },
1829 { DSYM_STANDARD,	25,	"PathTbl",	DSYM_UNUMBER16,	1,	0 },
1830 { DSYM_STANDARD,	26,	"MTU",		DSYM_UNUMBER16,	1,	1 },
1831 { DSYM_STANDARD,	27,	"SameMtuF",	DSYM_UNUMBER8,	1,	1 },
1832 { DSYM_STANDARD,	28,	"Broadcst",	DSYM_IP,	1,	1 },
1833 { DSYM_STANDARD,	29,	"MaskDscF",	DSYM_UNUMBER8,	1,	1 },
1834 { DSYM_STANDARD,	30,	"MaskSupF",	DSYM_UNUMBER8,	1,	1 },
1835 { DSYM_STANDARD,	31,	"RDiscvyF",	DSYM_UNUMBER8,	1,	1 },
1836 { DSYM_STANDARD,	32,	"RSolictS",	DSYM_IP,	1,	1 },
1837 { DSYM_STANDARD,	33,	"StaticRt",	DSYM_IP,	2,	0 },
1838 { DSYM_STANDARD,	34,	"TrailerF",	DSYM_UNUMBER8,	1,	1 },
1839 { DSYM_STANDARD,	35,	"ArpTimeO",	DSYM_UNUMBER32,	1,	1 },
1840 { DSYM_STANDARD,	36,	"EthEncap",	DSYM_UNUMBER8,	1,	1 },
1841 { DSYM_STANDARD,	37,	"TcpTTL",	DSYM_UNUMBER8,	1,	1 },
1842 { DSYM_STANDARD,	38,	"TcpKaInt",	DSYM_UNUMBER32,	1,	1 },
1843 { DSYM_STANDARD,	39,	"TcpKaGbF",	DSYM_UNUMBER8,	1,	1 },
1844 { DSYM_STANDARD,	40,	"NISdmain",	DSYM_ASCII,	1,	0 },
1845 { DSYM_STANDARD,	41,	"NISservs",	DSYM_IP,	1,	0 },
1846 { DSYM_STANDARD,	42,	"NTPservs",	DSYM_IP,	1,	0 },
1847 { DSYM_STANDARD,	43,	"Vendor",	DSYM_OCTET,	1,	0 },
1848 { DSYM_STANDARD,	44,	"NetBNms",	DSYM_IP,	1,	0 },
1849 { DSYM_STANDARD,	45,	"NetBDsts",	DSYM_IP,	1,	0 },
1850 { DSYM_STANDARD,	46,	"NetBNdT",	DSYM_UNUMBER8,	1,	1 },
1851 { DSYM_STANDARD,	47,	"NetBScop",	DSYM_ASCII,	1,	0 },
1852 { DSYM_STANDARD,	48,	"XFontSrv",	DSYM_IP,	1,	0 },
1853 { DSYM_STANDARD,	49,	"XDispMgr",	DSYM_IP,	1,	0 },
1854 { DSYM_STANDARD,	50,	"ReqIP",	DSYM_IP,	1,	1 },
1855 { DSYM_STANDARD,	51,	"LeaseTim",	DSYM_UNUMBER32,	1,	1 },
1856 { DSYM_STANDARD,	52,	"OptOvrld",	DSYM_UNUMBER8,	1,	1 },
1857 { DSYM_STANDARD,	53,	"DHCPType",	DSYM_UNUMBER8,	1,	1 },
1858 { DSYM_STANDARD,	54,	"ServerID",	DSYM_IP,	1,	1 },
1859 { DSYM_STANDARD,	55,	"ReqList",	DSYM_OCTET,	1,	0 },
1860 { DSYM_STANDARD,	56,	"Message",	DSYM_ASCII,	1,	0 },
1861 { DSYM_STANDARD,	57,	"DHCP_MTU",	DSYM_UNUMBER16,	1,	1 },
1862 { DSYM_STANDARD,	58,	"T1Time",	DSYM_UNUMBER32,	1,	1 },
1863 { DSYM_STANDARD,	59,	"T2Time",	DSYM_UNUMBER32,	1,	1 },
1864 { DSYM_STANDARD,	60,	"ClassID",	DSYM_ASCII,	1,	0 },
1865 { DSYM_STANDARD,	61,	"ClientID",	DSYM_OCTET,	1,	0 },
1866 { DSYM_STANDARD,	62,	"NW_dmain",	DSYM_ASCII,	1,	0 },
1867 { DSYM_STANDARD,	63,	"NWIPOpts",	DSYM_OCTET,	1,	128 },
1868 { DSYM_STANDARD,	64,	"NIS+dom",	DSYM_ASCII,	1,	0 },
1869 { DSYM_STANDARD,	65,	"NIS+serv",	DSYM_IP,	1,	0 },
1870 { DSYM_STANDARD,	66,	"TFTPsrvN",	DSYM_ASCII,	1,	64 },
1871 { DSYM_STANDARD,	67,	"OptBootF",	DSYM_ASCII,	1,	128 },
1872 { DSYM_STANDARD,	68,	"MblIPAgt",	DSYM_IP,	1,	0 },
1873 { DSYM_STANDARD,	69,	"SMTPserv",	DSYM_IP,	1,	0 },
1874 { DSYM_STANDARD,	70,	"POP3serv",	DSYM_IP,	1,	0 },
1875 { DSYM_STANDARD,	71,	"NNTPserv",	DSYM_IP,	1,	0 },
1876 { DSYM_STANDARD,	72,	"WWWservs",	DSYM_IP,	1,	0 },
1877 { DSYM_STANDARD,	73,	"Fingersv",	DSYM_IP,	1,	0 },
1878 { DSYM_STANDARD,	74,	"IRCservs",	DSYM_IP,	1,	0 },
1879 { DSYM_STANDARD,	75,	"STservs",	DSYM_IP,	1,	0 },
1880 { DSYM_STANDARD,	76,	"STDAservs",	DSYM_IP,	1,	0 },
1881 { DSYM_STANDARD,	77,	"UserClas",	DSYM_ASCII,	1,	0 },
1882 { DSYM_STANDARD,	78,	"SLP_DA",	DSYM_OCTET,	1,	0 },
1883 { DSYM_STANDARD,	79,	"SLP_SS",	DSYM_OCTET,	1,	0 },
1884 { DSYM_STANDARD,	82,	"AgentOpt",	DSYM_OCTET,	1,	0 },
1885 { DSYM_STANDARD,	89,	"FQDN",		DSYM_OCTET,	1,	0 },
1886 { 0,			0,	"",		0,		0,	0 }
1887 };
1888