xref: /illumos-gate/usr/src/lib/libslp/clib/slp_utils.c (revision 1da57d55)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * Miscellaneous Utilities
29  *
30  * slp_err:		Error and information message dispatch, i18n'd
31  * slp_start_call:	Marks a SLP handle as in-use
32  * slp_end_call:	Marks a SLP handle as available
33  * slp_map_err:		protocol to API error mapping
34  * slp_onlist:		determines if a token is on a list
35  * slp_add2list:	adds a token to a list
36  * slp_list_subtract:	removes a token from a list
37  * slp_add_header:	creates a SLP message header
38  * slp_get_length:	gets the length field from a SLP header
39  * slp_set_length:	sets the length field in a SLP header
40  * slp_header_get_sht:	gets a 16 bit integer from a SLP header
41  * slp_header_set_sht:	sets a 16 bit interger in a SLP header
42  * slp_header_length:	calculates the length of a header, including the
43  *				language tag
44  * slp_get_errcode:	returns the error code from a SLP message
45  * slp_add_byte:	encodes a byte into the given buffer
46  * slp_add_sht:		encodes a 16-bit integer into the given buffer
47  * slp_add_string:	encodes the given string into the given buffer
48  * slp_get_byte:	decodes a byte from the given buffer
49  * slp_get_sht:		decodes a 16-bit integer from the given buffer
50  * slp_get_string:	decodes a string from the given buffer
51  */
52 
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <stdarg.h>
56 #include <syslog.h>
57 #include <string.h>
58 #include <thread.h>
59 #include <synch.h>
60 #include <errno.h>
61 #include <unistd.h>
62 #include <limits.h>
63 #include <arpa/inet.h>
64 #include <libintl.h>
65 #include <slp-internal.h>
66 
67 #define	SLP_ERR_BUF_LEN	1024UL
68 
69 /*
70  * Outputs an error message. priority is a syslog(3) priority.
71  */
72 /*ARGSUSED1*/
73 /* PRINTFLIKE4 */
slp_err(int priority,int id,char * func,char * inmsg,...)74 void slp_err(int priority, int id, char *func, char *inmsg, ...) {
75 	static char buf[SLP_ERR_BUF_LEN];
76 	char *p, *msg;
77 	size_t len;
78 	va_list ap;
79 	static mutex_t loglock = DEFAULTMUTEX;
80 	va_start(ap, inmsg);
81 
82 	(void) mutex_lock(&loglock);
83 
84 	/* i18n mapping */
85 	msg = dgettext("libslp", inmsg);
86 
87 	(void) snprintf(buf, sizeof (buf), "libslp: %s: ", func);
88 	len = strlen(buf);
89 	p = &(buf[len]);
90 	(void) vsnprintf(p, SLP_ERR_BUF_LEN - len, msg, ap);
91 	va_end(ap);
92 	syslog(priority, buf);
93 	(void) mutex_unlock(&loglock);
94 }
95 
96 /*
97  * Start and end slp calls
98  * slp_start_call returns SLP_HANDLE_IN_USE if the handle is already
99  * being used, otherwise SLP_OK.
100  */
slp_start_call(slp_handle_impl_t * hp)101 SLPError slp_start_call(slp_handle_impl_t *hp) {
102 	(void) mutex_lock(&(hp->outcall_lock));
103 	if (hp->pending_outcall) {
104 	    (void) mutex_unlock(&(hp->outcall_lock));
105 	    return (SLP_HANDLE_IN_USE);
106 	}
107 	hp->pending_outcall = SLP_TRUE;
108 	(void) mutex_unlock(&(hp->outcall_lock));
109 
110 	hp->cancel = 0;
111 	return (SLP_OK);
112 }
113 
slp_end_call(slp_handle_impl_t * hp)114 void slp_end_call(slp_handle_impl_t *hp) {
115 	(void) mutex_lock(&(hp->outcall_lock));
116 	if (hp->close_on_end) {
117 	    /* SLPClose() called from callback */
118 	    (void) mutex_unlock(&(hp->outcall_lock));
119 	    slp_cleanup_handle(hp);
120 	    return;
121 	}
122 
123 	hp->pending_outcall = SLP_FALSE;
124 	(void) cond_signal(&(hp->outcall_cv));
125 	(void) mutex_unlock(&(hp->outcall_lock));
126 }
127 
128 /*
129  * Map a protocol error code to an API error code.
130  */
slp_map_err(unsigned short proto_err)131 SLPError slp_map_err(unsigned short proto_err) {
132 	switch (proto_err) {
133 	case 0:	return (SLP_OK);
134 	case 1:	return (SLP_LANGUAGE_NOT_SUPPORTED);
135 	case 2:	return (SLP_PARSE_ERROR);
136 	case 3:	return (SLP_INVALID_REGISTRATION);
137 	case 4:	return (SLP_SCOPE_NOT_SUPPORTED);
138 	case 6:	return (SLP_AUTHENTICATION_ABSENT);
139 	case 7:	return (SLP_AUTHENTICATION_FAILED);
140 	case 13:	return (SLP_INVALID_UPDATE);
141 		/*
142 		 * 9 (VER_NOT_SUPPORTED), 10 (INTERNAL_ERROR),
143 		 * 11 (DA_BUSY_NOW), 12 (OPTION_NOT_UNDERSTOOD),
144 		 * and 14 (RQST_NOT_SUPPORTED)
145 		 * should be handled internally by the API.
146 		 */
147 	default:	return (SLP_INTERNAL_SYSTEM_ERROR);
148 	}
149 }
150 
151 /*
152  * SLP List Management:
153  * SLP lists are comma separated lists of tokens. The following routines
154  * manage SLP lists, ensuring proper UTF-8 parsing.
155  */
156 
157 /*
158  * If 'item' is on 'list', returns 1, otherwise 0.
159  */
slp_onlist(const char * item,const char * list)160 int slp_onlist(const char *item, const char *list) {
161 	char *p;
162 	for (p = (char *)list; p; p++) {
163 		char *s;
164 		size_t span;
165 
166 		s = p;
167 		p = slp_utf_strchr(p, ',');
168 		span = (p ? (size_t)(p - s): strlen(s));
169 
170 		if (strlen(item) != span) {
171 			if (!p)
172 				break;
173 			else
174 				continue;
175 		}
176 
177 		if (strncasecmp(item, s, span) == 0)
178 			return (1);
179 		if (!p)
180 			break;
181 	}
182 	return (0);
183 }
184 
185 /*
186  * Adds item to *list if it is not already on it. If *list == NULL,
187  * creates a new list. When it grows the list, it will free *list,
188  * so *list must not be on the caller's stack. 'check_onlist' specifies
189  * whether to look to item on the current list. This is a small
190  * optimization for callers which are that item is not on *list, or
191  * which don't care about duplicates.
192  */
slp_add2list(const char * item,char ** list,SLPBoolean check_onlist)193 void slp_add2list(const char *item, char **list, SLPBoolean check_onlist) {
194 	if (!(*list)) {
195 		if (!(*list = strdup(item)))
196 			slp_err(LOG_CRIT, 0, "slp_add2list", "out of memory");
197 		return;
198 	}
199 
200 	if (check_onlist)
201 		/* no duplicates */
202 		if (slp_onlist(item, *list))
203 			return;
204 
205 	if (!(*list = realloc(*list, strlen(*list) + strlen(item) + 2))) {
206 		slp_err(LOG_CRIT, 0, "slp_add2list", "out of memory");
207 		return;
208 	}
209 	(void) strcat(*list, ",");
210 	(void) strcat(*list, item);
211 }
212 
213 /*
214  * Removes the first instance of item from *list.
215  * When it shrinks the list, it may free *list, so *list must not be on
216  * the caller's stack.
217  */
slp_list_subtract(const char * item,char ** list)218 void slp_list_subtract(const char *item, char **list) {
219 	char *p, *s;
220 
221 	if (!*list || !slp_onlist(item, *list))
222 		return;
223 	/* find item's location on the list */
224 	for (p = *list; p; p++) {
225 		size_t span;
226 
227 		s = p;
228 		p = slp_utf_strchr(p, ',');
229 		span = (p ? (size_t)(p - s) : strlen(s));
230 		if (strlen(item) != span)
231 			continue;
232 		if (strncasecmp(item, s, span) == 0)
233 			break;
234 		if (!p)
235 			break;
236 	}
237 	if (!p && s == *list) {
238 		/* item is only one on list */
239 		free(*list);
240 		*list = NULL;
241 		return;
242 	}
243 	if (!p) {
244 		/* last one on list; just chop it off */
245 		s--;
246 		*s = 0;
247 		return;
248 	}
249 	/* either first on list, or somewhere in the middle */
250 	(void) strcpy(s, p + 1);
251 }
252 
253 /* SLPv2 header management */
254 
255 /*
256  * Lays a SLP header into pcSendBuf, performing byte-ordering and bounds
257  * checking where necessary.
258  * pcLangTag: Language tag
259  * pcSendBuf: a buffer into which to write the composed header
260  * iSendBufSz: the size of pcSendBuf in bytes
261  * iFun: SLP V2 function number
262  * iLen: The length of the whole SLP message, in bytes
263  * piLen: a pointer to an int into which will be written the size of the
264  *	  header + the language tag (i.e. the offset at which the rest of
265  *	  the message should be written into pcSendBuf).
266  */
slp_add_header(const char * pcLangTag,char * pcSendBuf,size_t iSendBufSz,int iFun,size_t iLen,size_t * piLen)267 SLPError slp_add_header(const char *pcLangTag, char *pcSendBuf,
268 			size_t iSendBufSz, int iFun,
269 			size_t iLen, size_t *piLen) {
270 	unsigned short us, xid;
271 	static unsigned short xid_seeded = 0;
272 
273 	if (!xid_seeded) {
274 		static mutex_t lock = DEFAULTMUTEX;
275 		(void) mutex_lock(&lock);
276 		if (!xid_seeded) {
277 			/* generate a seed based on our PID */
278 			long long pid = getpid();
279 			pid *= UINT_MAX;
280 			(void) seed48((unsigned short *) &pid);
281 			xid_seeded = 1;
282 		}
283 		(void) mutex_unlock(&lock);
284 	}
285 	/* squish the random value into an unsigned short */
286 	xid = (unsigned short) (lrand48() % USHRT_MAX);
287 	xid = xid ? xid : 1;	/* 0 is for DAs only */
288 
289 	us = (unsigned short) strlen(pcLangTag);
290 	if ((SLP_HDRLEN + us) > iSendBufSz)
291 		return (SLP_PARAMETER_BAD);
292 
293 	(void) memset(pcSendBuf, 0, SLP_HDRLEN);
294 
295 	slp_set_version(pcSendBuf, SLP_VERSION);
296 	slp_set_function(pcSendBuf, (char)iFun);
297 	slp_set_length(pcSendBuf, iLen);
298 	slp_set_xid(pcSendBuf, xid);
299 	slp_set_langlen(pcSendBuf, us);
300 	(void) memcpy(&pcSendBuf[SLP_HDRLEN], pcLangTag, us);
301 
302 	*piLen = SLP_HDRLEN + us;
303 	return (SLP_OK);
304 }
305 
306 /*
307  * Retrieves the 24 bit int stored at 'off' offset into 'header'.
308  * Assumes 'header' is a valid SLP message header.
309  */
slp_header_get_int24(const char * header,size_t off)310 unsigned int slp_header_get_int24(const char *header, size_t off) {
311 	unsigned int len;
312 
313 	len = ((unsigned int)(header[off] & 0xff)) << 16;
314 	len += ((unsigned int)(header[off + 1] & 0xff)) << 8;
315 	len += ((unsigned int)(header[off + 2] & 0xff));
316 
317 	return (len);
318 }
319 
320 /*
321  * Sets a 24 bit int at the location in 'header' 'off' bytes
322  * offset into the header.
323  * Assumes 'header' is a valid SLP message header.
324  */
slp_header_set_int24(char * header,unsigned int len,size_t off)325 void slp_header_set_int24(char *header, unsigned int len, size_t off) {
326 	header[off] = (unsigned char) ((len & 0xff0000) >> 16);
327 	header[off + 1] = (unsigned char) ((len & 0xff00) >> 8);
328 	header[off + 2] = (unsigned char) (len & 0xff);
329 }
330 
331 /*
332  * Retrieves the 16 bit integer stored at 'off' offset into 'header'.
333  * Assumes 'header' is a valid SLP message header.
334  */
slp_header_get_sht(const char * header,size_t off)335 unsigned short slp_header_get_sht(const char *header, size_t off) {
336 	unsigned short answer = 0;
337 	(void) slp_get_sht(header, SLP_HDRLEN, &off, &answer);
338 	return (answer);
339 }
340 
341 /*
342  * Sets a 16 bit interger at the location in 'header' 'off' bytes
343  * offset into the header.
344  * Assumes 'header' is a valid SLP message header.
345  */
slp_header_set_sht(char * header,unsigned short len,size_t off)346 void slp_header_set_sht(char *header, unsigned short len, size_t off) {
347 	(void) slp_add_sht(header, SLP_HDRLEN, len, &off);
348 }
349 
350 /*
351  * Returns the total length of a SLP header associated with the SLP
352  * handle 'hp', including the language tag.
353  */
slp_header_length(slp_handle_impl_t * hp)354 size_t slp_header_length(slp_handle_impl_t *hp) {
355 	return (SLP_HDRLEN + strlen(hp->locale));
356 }
357 
358 /*
359  * Retrieves the error code for UA replies -- the errcode is always
360  * the first short after the header for these functions. 'msg' points to
361  * the beginning of a SLP header.
362  */
slp_get_errcode(char * msg)363 slp_proto_err slp_get_errcode(char *msg) {
364 	unsigned short langlen, errcode;
365 	size_t off, msglen;
366 
367 	/* make sure the reply is long enough */
368 	msglen = slp_get_length(msg);
369 	if (msglen < (SLP_LANGLEN + 2))
370 		return (SLP_MSG_PARSE_ERROR);
371 	langlen = slp_get_langlen(msg);
372 	off = SLP_HDRLEN + langlen;
373 
374 	if (slp_get_sht(msg, msglen, &off, &errcode) != SLP_OK)
375 		return (SLP_MSG_PARSE_ERROR);
376 
377 	return (errcode);
378 }
379 
380 /*
381  * Primitive Encoding and Decoding Routines.
382  * All perform byte-ordering coversions and bounds checking.
383  */
384 
slp_add_byte(char * pcBuf,size_t iBufSz,int iVal,size_t * piLen)385 SLPError slp_add_byte(char *pcBuf, size_t iBufSz, int iVal,
386 			size_t *piLen) {
387 	if ((*piLen + 1) > iBufSz)
388 		return (SLP_PARAMETER_BAD);
389 
390 	pcBuf[(*piLen)++] = (unsigned char) iVal;
391 	return (SLP_OK);
392 }
393 
slp_add_sht(char * pcBuf,size_t iBufSz,unsigned short iVal,size_t * piLen)394 SLPError slp_add_sht(char *pcBuf, size_t iBufSz, unsigned short iVal,
395 			size_t *piLen) {
396 	if ((*piLen + 2) > iBufSz)
397 		return (SLP_PARAMETER_BAD);
398 
399 	pcBuf[(*piLen)++] = (unsigned char) ((iVal & 0xFF00) >> 8);
400 	pcBuf[(*piLen)++] = (unsigned char) (iVal & 0xFF);
401 	return (SLP_OK);
402 }
403 
slp_add_int32(char * pcBuf,size_t iBufSz,unsigned int iVal,size_t * piLen)404 SLPError slp_add_int32(char *pcBuf, size_t iBufSz, unsigned int iVal,
405 			size_t *piLen) {
406 	if ((*piLen + 4) > iBufSz)
407 		return (SLP_PARAMETER_BAD);
408 
409 	pcBuf[(*piLen)++] = (unsigned char) ((iVal & 0xFF000000) >> 24);
410 	pcBuf[(*piLen)++] = (unsigned char) ((iVal & 0xFF0000) >> 16);
411 	pcBuf[(*piLen)++] = (unsigned char) ((iVal & 0xFF00) >> 8);
412 	pcBuf[(*piLen)++] = (unsigned char) (iVal & 0xFF);
413 
414 	return (SLP_OK);
415 }
416 
slp_add_string(char * pcBuf,size_t iBufSz,const char * pcStr,size_t * piLen)417 SLPError slp_add_string(char *pcBuf, size_t iBufSz, const char *pcStr,
418 			size_t *piLen) {
419 	size_t iStrLen = strlen(pcStr);
420 	SLPError err = 0;
421 
422 	if (iStrLen > USHRT_MAX)
423 		/* SLP strings are limited to 16-bit len */
424 		return (SLP_PARAMETER_BAD);
425 	if ((iStrLen + *piLen + 2) > iBufSz)
426 		return (SLP_PARAMETER_BAD);
427 
428 	if ((err = slp_add_sht(pcBuf, iBufSz, (unsigned short)iStrLen, piLen))
429 	    != SLP_OK)
430 		return (err);
431 
432 	(void) memcpy(&(pcBuf[*piLen]), pcStr, iStrLen);
433 	*piLen += iStrLen;
434 	return (SLP_OK);
435 }
436 
slp_get_byte(const char * pcBuf,size_t maxlen,size_t * piOffset,int * piByte)437 SLPError slp_get_byte(const char *pcBuf, size_t maxlen,
438 			size_t *piOffset, int *piByte) {
439 	size_t offset = 0;
440 
441 	if (piOffset != NULL) {
442 		if ((*piOffset+1) > maxlen)
443 			return (SLP_PARSE_ERROR);
444 		offset = *piOffset;
445 		*piOffset += 1;
446 	}
447 
448 	*piByte = (int)pcBuf[offset];
449 	return (SLP_OK);
450 }
451 
slp_get_sht(const char * pcBuf,size_t maxlen,size_t * piOffset,unsigned short * piSht)452 SLPError slp_get_sht(const char *pcBuf, size_t maxlen,
453 			size_t *piOffset, unsigned short *piSht) {
454 	size_t offset = 0;
455 
456 	if (piOffset != NULL) {
457 		if ((*piOffset+2) > maxlen)
458 			return (SLP_PARSE_ERROR);
459 		offset = *piOffset;
460 		*piOffset += 2;
461 	}
462 
463 	*piSht = (unsigned short)
464 		((unsigned char)pcBuf[offset] & (unsigned char)0xFF);
465 	*piSht <<= 8;
466 	*piSht += (unsigned short)
467 		((unsigned char)pcBuf[offset+1] & (unsigned char)0xFF);
468 
469 	return (SLP_OK);
470 }
471 
slp_get_int32(const char * pcBuf,size_t maxlen,size_t * piOffset,unsigned int * piInt)472 SLPError slp_get_int32(const char *pcBuf, size_t maxlen,
473 			size_t *piOffset, unsigned int *piInt) {
474 	size_t offset = 0;
475 
476 	if (piOffset != NULL) {
477 		if ((*piOffset+4) > maxlen)
478 			return (SLP_PARSE_ERROR);
479 		offset = *piOffset;
480 		*piOffset += 4;
481 	}
482 
483 	*piInt = ((unsigned int)(pcBuf[offset] & 0xff)) << 24;
484 	*piInt += ((unsigned int)(pcBuf[offset+1] & 0xff)) << 16;
485 	*piInt += ((unsigned int)(pcBuf[offset+2] & 0xff)) << 8;
486 	*piInt += ((unsigned int)(pcBuf[offset+3] & 0xff));
487 
488 	return (SLP_OK);
489 }
490 
slp_get_string(const char * pcBuf,size_t iMaxLen,size_t * piOffset,char ** ppcString)491 SLPError slp_get_string(const char *pcBuf, size_t iMaxLen,
492 		    size_t *piOffset, char **ppcString) {
493 	SLPError err;
494 	unsigned short iLen;
495 
496 	*ppcString = NULL;
497 	err = slp_get_sht(pcBuf, iMaxLen, piOffset, &iLen);
498 	if (err)
499 		return (err);
500 	if ((iLen+*piOffset) > iMaxLen)
501 		return (SLP_PARSE_ERROR);
502 
503 	if (!(*ppcString = malloc(iLen + 1))) {
504 		slp_err(LOG_CRIT, 0, "slp_get_string", "out of memory");
505 		return (SLP_MEMORY_ALLOC_FAILED);
506 	}
507 	(void) memcpy(*ppcString, pcBuf + *piOffset, iLen);
508 	(*ppcString)[iLen] = 0;
509 	*piOffset += iLen;
510 	return (SLP_OK);
511 }
512