1/*
2 * SNMP functions for CUPS.
3 *
4 * Copyright 2007-2014 by Apple Inc.
5 * Copyright 2006-2007 by Easy Software Products, all rights reserved.
6 *
7 * These coded instructions, statements, and computer programs are the
8 * property of Apple Inc. and are protected by Federal copyright
9 * law.  Distribution and use rights are outlined in the file "LICENSE.txt"
10 * "LICENSE" which should have been included with this file.  If this
11 * file is missing or damaged, see the license at "http://www.cups.org/".
12 *
13 * This file is subject to the Apple OS-Developed Software exception.
14 */
15
16/*
17 * Include necessary headers.
18 */
19
20#include "cups-private.h"
21#include "snmp-private.h"
22#ifdef HAVE_POLL
23#  include <poll.h>
24#endif /* HAVE_POLL */
25
26
27/*
28 * Local functions...
29 */
30
31static void		asn1_debug(const char *prefix, unsigned char *buffer,
32			           size_t len, int indent);
33static int		asn1_decode_snmp(unsigned char *buffer, size_t len,
34			                 cups_snmp_t *packet);
35static int		asn1_encode_snmp(unsigned char *buffer, size_t len,
36			                 cups_snmp_t *packet);
37static int		asn1_get_integer(unsigned char **buffer,
38			                 unsigned char *bufend,
39			                 unsigned length);
40static int		asn1_get_oid(unsigned char **buffer,
41			             unsigned char *bufend,
42				     unsigned length, int *oid, int oidsize);
43static int		asn1_get_packed(unsigned char **buffer,
44			                unsigned char *bufend);
45static char		*asn1_get_string(unsigned char **buffer,
46			                 unsigned char *bufend,
47			                 unsigned length, char *string,
48			                 size_t strsize);
49static unsigned		asn1_get_length(unsigned char **buffer,
50			                unsigned char *bufend);
51static int		asn1_get_type(unsigned char **buffer,
52			              unsigned char *bufend);
53static void		asn1_set_integer(unsigned char **buffer,
54			                 int integer);
55static void		asn1_set_length(unsigned char **buffer,
56			                unsigned length);
57static void		asn1_set_oid(unsigned char **buffer,
58			             const int *oid);
59static void		asn1_set_packed(unsigned char **buffer,
60			                int integer);
61static unsigned		asn1_size_integer(int integer);
62static unsigned		asn1_size_length(unsigned length);
63static unsigned		asn1_size_oid(const int *oid);
64static unsigned		asn1_size_packed(int integer);
65static void		snmp_set_error(cups_snmp_t *packet,
66			               const char *message);
67
68
69/*
70 * '_cupsSNMPClose()' - Close a SNMP socket.
71 */
72
73void
74_cupsSNMPClose(int fd)			/* I - SNMP socket file descriptor */
75{
76  DEBUG_printf(("4_cupsSNMPClose(fd=%d)", fd));
77
78  httpAddrClose(NULL, fd);
79}
80
81
82/*
83 * '_cupsSNMPCopyOID()' - Copy an OID.
84 *
85 * The array pointed to by "src" is terminated by the value -1.
86 */
87
88int *					/* O - New OID */
89_cupsSNMPCopyOID(int       *dst,	/* I - Destination OID */
90                 const int *src,	/* I - Source OID */
91		 int       dstsize)	/* I - Number of integers in dst */
92{
93  int	i;				/* Looping var */
94
95
96  DEBUG_printf(("4_cupsSNMPCopyOID(dst=%p, src=%p, dstsize=%d)", dst, src,
97                dstsize));
98
99  for (i = 0, dstsize --; src[i] >= 0 && i < dstsize; i ++)
100    dst[i] = src[i];
101
102  dst[i] = -1;
103
104  return (dst);
105}
106
107
108/*
109 * '_cupsSNMPDefaultCommunity()' - Get the default SNMP community name.
110 *
111 * The default community name is the first community name found in the
112 * snmp.conf file. If no community name is defined there, "public" is used.
113 */
114
115const char *				/* O - Default community name */
116_cupsSNMPDefaultCommunity(void)
117{
118  cups_file_t	*fp;			/* snmp.conf file */
119  char		line[1024],		/* Line from file */
120		*value;			/* Value from file */
121  int		linenum;		/* Line number in file */
122  _cups_globals_t *cg = _cupsGlobals();	/* Global data */
123
124
125  DEBUG_puts("4_cupsSNMPDefaultCommunity()");
126
127  if (!cg->snmp_community[0])
128  {
129    strlcpy(cg->snmp_community, "public", sizeof(cg->snmp_community));
130
131    snprintf(line, sizeof(line), "%s/snmp.conf", cg->cups_serverroot);
132    if ((fp = cupsFileOpen(line, "r")) != NULL)
133    {
134      linenum = 0;
135      while (cupsFileGetConf(fp, line, sizeof(line), &value, &linenum))
136	if (!_cups_strcasecmp(line, "Community") && value)
137	{
138	  strlcpy(cg->snmp_community, value, sizeof(cg->snmp_community));
139	  break;
140	}
141
142      cupsFileClose(fp);
143    }
144  }
145
146  DEBUG_printf(("5_cupsSNMPDefaultCommunity: Returning \"%s\"",
147                cg->snmp_community));
148
149  return (cg->snmp_community);
150}
151
152
153/*
154 * '_cupsSNMPIsOID()' - Test whether a SNMP response contains the specified OID.
155 *
156 * The array pointed to by "oid" is terminated by the value -1.
157 */
158
159int					/* O - 1 if equal, 0 if not equal */
160_cupsSNMPIsOID(cups_snmp_t *packet,	/* I - Response packet */
161               const int   *oid)	/* I - OID */
162{
163  int	i;				/* Looping var */
164
165
166 /*
167  * Range check input...
168  */
169
170  DEBUG_printf(("4_cupsSNMPIsOID(packet=%p, oid=%p)", packet, oid));
171
172  if (!packet || !oid)
173  {
174    DEBUG_puts("5_cupsSNMPIsOID: Returning 0");
175
176    return (0);
177  }
178
179 /*
180  * Compare OIDs...
181  */
182
183  for (i = 0;
184       i < CUPS_SNMP_MAX_OID && oid[i] >= 0 && packet->object_name[i] >= 0;
185       i ++)
186    if (oid[i] != packet->object_name[i])
187    {
188      DEBUG_puts("5_cupsSNMPIsOID: Returning 0");
189
190      return (0);
191    }
192
193  DEBUG_printf(("5_cupsSNMPIsOID: Returning %d",
194                i < CUPS_SNMP_MAX_OID && oid[i] == packet->object_name[i]));
195
196  return (i < CUPS_SNMP_MAX_OID && oid[i] == packet->object_name[i]);
197}
198
199
200/*
201 * '_cupsSNMPIsOIDPrefixed()' - Test whether a SNMP response uses the specified
202 *                              OID prefix.
203 *
204 * The array pointed to by "prefix" is terminated by the value -1.
205 */
206
207int					/* O - 1 if prefixed, 0 if not prefixed */
208_cupsSNMPIsOIDPrefixed(
209    cups_snmp_t *packet,		/* I - Response packet */
210    const int   *prefix)		/* I - OID prefix */
211{
212  int	i;				/* Looping var */
213
214
215 /*
216  * Range check input...
217  */
218
219  DEBUG_printf(("4_cupsSNMPIsOIDPrefixed(packet=%p, prefix=%p)", packet,
220                prefix));
221
222  if (!packet || !prefix)
223  {
224    DEBUG_puts("5_cupsSNMPIsOIDPrefixed: Returning 0");
225
226    return (0);
227  }
228
229 /*
230  * Compare OIDs...
231  */
232
233  for (i = 0;
234       i < CUPS_SNMP_MAX_OID && prefix[i] >= 0 && packet->object_name[i] >= 0;
235       i ++)
236    if (prefix[i] != packet->object_name[i])
237    {
238      DEBUG_puts("5_cupsSNMPIsOIDPrefixed: Returning 0");
239
240      return (0);
241    }
242
243  DEBUG_printf(("5_cupsSNMPIsOIDPrefixed: Returning %d",
244                i < CUPS_SNMP_MAX_OID));
245
246  return (i < CUPS_SNMP_MAX_OID);
247}
248
249
250/*
251 * '_cupsSNMPOIDToString()' - Convert an OID to a string.
252 */
253
254
255char *					/* O - New string or @code NULL@ on error */
256_cupsSNMPOIDToString(const int *src,	/* I - OID */
257                     char      *dst,	/* I - String buffer */
258                     size_t    dstsize)	/* I - Size of string buffer */
259{
260  char	*dstptr,			/* Pointer into string buffer */
261	*dstend;			/* End of string buffer */
262
263
264  DEBUG_printf(("4_cupsSNMPOIDToString(src=%p, dst=%p, dstsize=" CUPS_LLFMT ")",
265                src, dst, CUPS_LLCAST dstsize));
266
267 /*
268  * Range check input...
269  */
270
271  if (!src || !dst || dstsize < 4)
272    return (NULL);
273
274 /*
275  * Loop through the OID array and build a string...
276  */
277
278  for (dstptr = dst, dstend = dstptr + dstsize - 1;
279       *src >= 0 && dstptr < dstend;
280       src ++, dstptr += strlen(dstptr))
281    snprintf(dstptr, (size_t)(dstend - dstptr + 1), ".%d", *src);
282
283  if (*src >= 0)
284    return (NULL);
285  else
286    return (dst);
287}
288
289
290/*
291 * '_cupsSNMPOpen()' - Open a SNMP socket.
292 */
293
294int					/* O - SNMP socket file descriptor */
295_cupsSNMPOpen(int family)		/* I - Address family - @code AF_INET@ or @code AF_INET6@ */
296{
297  int		fd;			/* SNMP socket file descriptor */
298  int		val;			/* Socket option value */
299
300
301 /*
302  * Create the SNMP socket...
303  */
304
305  DEBUG_printf(("4_cupsSNMPOpen(family=%d)", family));
306
307  if ((fd = socket(family, SOCK_DGRAM, 0)) < 0)
308  {
309    DEBUG_printf(("5_cupsSNMPOpen: Returning -1 (%s)", strerror(errno)));
310
311    return (-1);
312  }
313
314 /*
315  * Set the "broadcast" flag...
316  */
317
318  val = 1;
319
320  if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, CUPS_SOCAST &val, sizeof(val)))
321  {
322    DEBUG_printf(("5_cupsSNMPOpen: Returning -1 (%s)", strerror(errno)));
323
324    close(fd);
325
326    return (-1);
327  }
328
329  DEBUG_printf(("5_cupsSNMPOpen: Returning %d", fd));
330
331  return (fd);
332}
333
334
335/*
336 * '_cupsSNMPRead()' - Read and parse a SNMP response.
337 *
338 * If "timeout" is negative, @code _cupsSNMPRead@ will wait for a response
339 * indefinitely.
340 */
341
342cups_snmp_t *				/* O - SNMP packet or @code NULL@ if none */
343_cupsSNMPRead(int         fd,		/* I - SNMP socket file descriptor */
344              cups_snmp_t *packet,	/* I - SNMP packet buffer */
345	      double      timeout)	/* I - Timeout in seconds */
346{
347  unsigned char	buffer[CUPS_SNMP_MAX_PACKET];
348					/* Data packet */
349  ssize_t	bytes;			/* Number of bytes received */
350  socklen_t	addrlen;		/* Source address length */
351  http_addr_t	address;		/* Source address */
352
353
354 /*
355  * Range check input...
356  */
357
358  DEBUG_printf(("4_cupsSNMPRead(fd=%d, packet=%p, timeout=%.1f)", fd, packet,
359                timeout));
360
361  if (fd < 0 || !packet)
362  {
363    DEBUG_puts("5_cupsSNMPRead: Returning NULL");
364
365    return (NULL);
366  }
367
368 /*
369  * Optionally wait for a response...
370  */
371
372  if (timeout >= 0.0)
373  {
374    int			ready;		/* Data ready on socket? */
375#ifdef HAVE_POLL
376    struct pollfd	pfd;		/* Polled file descriptor */
377
378    pfd.fd     = fd;
379    pfd.events = POLLIN;
380
381    while ((ready = poll(&pfd, 1, (int)(timeout * 1000.0))) < 0 &&
382           (errno == EINTR || errno == EAGAIN));
383
384#else
385    fd_set		input_set;	/* select() input set */
386    struct timeval	stimeout;	/* select() timeout */
387
388    do
389    {
390      FD_ZERO(&input_set);
391      FD_SET(fd, &input_set);
392
393      stimeout.tv_sec  = (int)timeout;
394      stimeout.tv_usec = (int)((timeout - stimeout.tv_sec) * 1000000);
395
396      ready = select(fd + 1, &input_set, NULL, NULL, &stimeout);
397    }
398#  ifdef WIN32
399    while (ready < 0 && WSAGetLastError() == WSAEINTR);
400#  else
401    while (ready < 0 && (errno == EINTR || errno == EAGAIN));
402#  endif /* WIN32 */
403#endif /* HAVE_POLL */
404
405   /*
406    * If we don't have any data ready, return right away...
407    */
408
409    if (ready <= 0)
410    {
411      DEBUG_puts("5_cupsSNMPRead: Returning NULL (timeout)");
412
413      return (NULL);
414    }
415  }
416
417 /*
418  * Read the response data...
419  */
420
421  addrlen = sizeof(address);
422
423  if ((bytes = recvfrom(fd, buffer, sizeof(buffer), 0, (void *)&address,
424                        &addrlen)) < 0)
425  {
426    DEBUG_printf(("5_cupsSNMPRead: Returning NULL (%s)", strerror(errno)));
427
428    return (NULL);
429  }
430
431 /*
432  * Look for the response status code in the SNMP message header...
433  */
434
435  asn1_debug("DEBUG: IN ", buffer, (size_t)bytes, 0);
436
437  asn1_decode_snmp(buffer, (size_t)bytes, packet);
438
439  memcpy(&(packet->address), &address, sizeof(packet->address));
440
441 /*
442  * Return decoded data packet...
443  */
444
445  DEBUG_puts("5_cupsSNMPRead: Returning packet");
446
447  return (packet);
448}
449
450
451/*
452 * '_cupsSNMPSetDebug()' - Enable/disable debug logging to stderr.
453 */
454
455void
456_cupsSNMPSetDebug(int level)		/* I - 1 to enable debug output, 0 otherwise */
457{
458  _cups_globals_t *cg = _cupsGlobals();	/* Global data */
459
460
461  DEBUG_printf(("4_cupsSNMPSetDebug(level=%d)", level));
462
463  cg->snmp_debug = level;
464}
465
466
467/*
468 * '_cupsSNMPStringToOID()' - Convert a numeric OID string to an OID array.
469 *
470 * This function converts a string of the form ".N.N.N.N.N" to the
471 * corresponding OID array terminated by -1.
472 *
473 * @code NULL@ is returned if the array is not large enough or the string is
474 * not a valid OID number.
475 */
476
477int *					/* O - Pointer to OID array or @code NULL@ on error */
478_cupsSNMPStringToOID(const char *src,	/* I - OID string */
479                     int        *dst,	/* I - OID array */
480		     int        dstsize)/* I - Number of integers in OID array */
481{
482  int	*dstptr,			/* Pointer into OID array */
483	*dstend;			/* End of OID array */
484
485
486  DEBUG_printf(("4_cupsSNMPStringToOID(src=\"%s\", dst=%p, dstsize=%d)",
487                src, dst, dstsize));
488
489 /*
490  * Range check input...
491  */
492
493  if (!src || !dst || dstsize < 2)
494    return (NULL);
495
496 /*
497  * Skip leading "."...
498  */
499
500  if (*src == '.')
501    src ++;
502
503 /*
504  * Loop to the end of the string...
505  */
506
507  for (dstend = dst + dstsize - 1, dstptr = dst, *dstptr = 0;
508       *src && dstptr < dstend;
509       src ++)
510  {
511    if (*src == '.')
512    {
513      dstptr ++;
514      *dstptr = 0;
515    }
516    else if (isdigit(*src & 255))
517      *dstptr = *dstptr * 10 + *src - '0';
518    else
519      break;
520  }
521
522  if (*src)
523    return (NULL);
524
525 /*
526  * Terminate the end of the OID array and return...
527  */
528
529  dstptr[1] = -1;
530
531  return (dst);
532}
533
534
535/*
536 * '_cupsSNMPWalk()' - Enumerate a group of OIDs.
537 *
538 * This function queries all of the OIDs with the specified OID prefix,
539 * calling the "cb" function for every response that is received.
540 *
541 * The array pointed to by "prefix" is terminated by the value -1.
542 *
543 * If "timeout" is negative, @code _cupsSNMPWalk@ will wait for a response
544 * indefinitely.
545 */
546
547int					/* O - Number of OIDs found or -1 on error */
548_cupsSNMPWalk(int            fd,	/* I - SNMP socket */
549              http_addr_t    *address,	/* I - Address to query */
550	      int            version,	/* I - SNMP version */
551	      const char     *community,/* I - Community name */
552              const int      *prefix,	/* I - OID prefix */
553	      double         timeout,	/* I - Timeout for each response in seconds */
554	      cups_snmp_cb_t cb,	/* I - Function to call for each response */
555	      void           *data)	/* I - User data pointer that is passed to the callback function */
556{
557  int		count = 0;		/* Number of OIDs found */
558  unsigned	request_id = 0;		/* Current request ID */
559  cups_snmp_t	packet;			/* Current response packet */
560  int		lastoid[CUPS_SNMP_MAX_OID];
561					/* Last OID we got */
562
563
564 /*
565  * Range check input...
566  */
567
568  DEBUG_printf(("4_cupsSNMPWalk(fd=%d, address=%p, version=%d, "
569                "community=\"%s\", prefix=%p, timeout=%.1f, cb=%p, data=%p)",
570		fd, address, version, community, prefix, timeout, cb, data));
571
572  if (fd < 0 || !address || version != CUPS_SNMP_VERSION_1 || !community ||
573      !prefix || !cb)
574  {
575    DEBUG_puts("5_cupsSNMPWalk: Returning -1");
576
577    return (-1);
578  }
579
580 /*
581  * Copy the OID prefix and then loop until we have no more OIDs...
582  */
583
584  _cupsSNMPCopyOID(packet.object_name, prefix, CUPS_SNMP_MAX_OID);
585  lastoid[0] = -1;
586
587  for (;;)
588  {
589    request_id ++;
590
591    if (!_cupsSNMPWrite(fd, address, version, community,
592                        CUPS_ASN1_GET_NEXT_REQUEST, request_id,
593		        packet.object_name))
594    {
595      DEBUG_puts("5_cupsSNMPWalk: Returning -1");
596
597      return (-1);
598    }
599
600    if (!_cupsSNMPRead(fd, &packet, timeout))
601    {
602      DEBUG_puts("5_cupsSNMPWalk: Returning -1");
603
604      return (-1);
605    }
606
607    if (!_cupsSNMPIsOIDPrefixed(&packet, prefix) ||
608        _cupsSNMPIsOID(&packet, lastoid))
609    {
610      DEBUG_printf(("5_cupsSNMPWalk: Returning %d", count));
611
612      return (count);
613    }
614
615    if (packet.error || packet.error_status)
616    {
617      DEBUG_printf(("5_cupsSNMPWalk: Returning %d", count > 0 ? count : -1));
618
619      return (count > 0 ? count : -1);
620    }
621
622    _cupsSNMPCopyOID(lastoid, packet.object_name, CUPS_SNMP_MAX_OID);
623
624    count ++;
625
626    (*cb)(&packet, data);
627  }
628}
629
630
631/*
632 * '_cupsSNMPWrite()' - Send an SNMP query packet.
633 *
634 * The array pointed to by "oid" is terminated by the value -1.
635 */
636
637int					/* O - 1 on success, 0 on error */
638_cupsSNMPWrite(
639    int            fd,			/* I - SNMP socket */
640    http_addr_t    *address,		/* I - Address to send to */
641    int            version,		/* I - SNMP version */
642    const char     *community,		/* I - Community name */
643    cups_asn1_t    request_type,	/* I - Request type */
644    const unsigned request_id,		/* I - Request ID */
645    const int      *oid)		/* I - OID */
646{
647  int		i;			/* Looping var */
648  cups_snmp_t	packet;			/* SNMP message packet */
649  unsigned char	buffer[CUPS_SNMP_MAX_PACKET];
650					/* SNMP message buffer */
651  ssize_t	bytes;			/* Size of message */
652  http_addr_t	temp;			/* Copy of address */
653
654
655 /*
656  * Range check input...
657  */
658
659  DEBUG_printf(("4_cupsSNMPWrite(fd=%d, address=%p, version=%d, "
660                "community=\"%s\", request_type=%d, request_id=%u, oid=%p)",
661		fd, address, version, community, request_type, request_id, oid));
662
663  if (fd < 0 || !address || version != CUPS_SNMP_VERSION_1 || !community ||
664      (request_type != CUPS_ASN1_GET_REQUEST &&
665       request_type != CUPS_ASN1_GET_NEXT_REQUEST) || request_id < 1 || !oid)
666  {
667    DEBUG_puts("5_cupsSNMPWrite: Returning 0 (bad arguments)");
668
669    return (0);
670  }
671
672 /*
673  * Create the SNMP message...
674  */
675
676  memset(&packet, 0, sizeof(packet));
677
678  packet.version      = version;
679  packet.request_type = request_type;
680  packet.request_id   = request_id;
681  packet.object_type  = CUPS_ASN1_NULL_VALUE;
682
683  strlcpy(packet.community, community, sizeof(packet.community));
684
685  for (i = 0; oid[i] >= 0 && i < (CUPS_SNMP_MAX_OID - 1); i ++)
686    packet.object_name[i] = oid[i];
687  packet.object_name[i] = -1;
688
689  if (oid[i] >= 0)
690  {
691    DEBUG_puts("5_cupsSNMPWrite: Returning 0 (OID too big)");
692
693    errno = E2BIG;
694    return (0);
695  }
696
697  bytes = asn1_encode_snmp(buffer, sizeof(buffer), &packet);
698
699  if (bytes < 0)
700  {
701    DEBUG_puts("5_cupsSNMPWrite: Returning 0 (request too big)");
702
703    errno = E2BIG;
704    return (0);
705  }
706
707  asn1_debug("DEBUG: OUT ", buffer, (size_t)bytes, 0);
708
709 /*
710  * Send the message...
711  */
712
713  temp = *address;
714
715  _httpAddrSetPort(&temp, CUPS_SNMP_PORT);
716
717  return (sendto(fd, buffer, (size_t)bytes, 0, (void *)&temp, (socklen_t)httpAddrLength(&temp)) == bytes);
718}
719
720
721/*
722 * 'asn1_debug()' - Decode an ASN1-encoded message.
723 */
724
725static void
726asn1_debug(const char    *prefix,	/* I - Prefix string */
727           unsigned char *buffer,	/* I - Buffer */
728           size_t        len,		/* I - Length of buffer */
729           int           indent)	/* I - Indentation */
730{
731  size_t	i;			/* Looping var */
732  unsigned char	*bufend;		/* End of buffer */
733  int		integer;		/* Number value */
734  int		oid[CUPS_SNMP_MAX_OID];	/* OID value */
735  char		string[CUPS_SNMP_MAX_STRING];
736					/* String value */
737  unsigned char	value_type;		/* Type of value */
738  unsigned	value_length;		/* Length of value */
739  _cups_globals_t *cg = _cupsGlobals();	/* Global data */
740
741
742  if (cg->snmp_debug <= 0)
743    return;
744
745  if (cg->snmp_debug > 1 && indent == 0)
746  {
747   /*
748    * Do a hex dump of the packet...
749    */
750
751    size_t j;
752
753    fprintf(stderr, "%sHex Dump (%d bytes):\n", prefix, (int)len);
754
755    for (i = 0; i < len; i += 16)
756    {
757      fprintf(stderr, "%s%04x:", prefix, (unsigned)i);
758
759      for (j = 0; j < 16 && (i + j) < len; j ++)
760      {
761        if (j && !(j & 3))
762	  fprintf(stderr, "  %02x", buffer[i + j]);
763        else
764	  fprintf(stderr, " %02x", buffer[i + j]);
765      }
766
767      while (j < 16)
768      {
769        if (j && !(j & 3))
770	  fputs("    ", stderr);
771	else
772	  fputs("   ", stderr);
773
774        j ++;
775      }
776
777      fputs("    ", stderr);
778
779      for (j = 0; j < 16 && (i + j) < len; j ++)
780        if (buffer[i + j] < ' ' || buffer[i + j] >= 0x7f)
781	  putc('.', stderr);
782	else
783	  putc(buffer[i + j], stderr);
784
785      putc('\n', stderr);
786    }
787  }
788
789  if (indent == 0)
790    fprintf(stderr, "%sMessage:\n", prefix);
791
792  bufend = buffer + len;
793
794  while (buffer < bufend)
795  {
796   /*
797    * Get value type...
798    */
799
800    value_type   = (unsigned char)asn1_get_type(&buffer, bufend);
801    value_length = asn1_get_length(&buffer, bufend);
802
803    switch (value_type)
804    {
805      case CUPS_ASN1_BOOLEAN :
806          integer = asn1_get_integer(&buffer, bufend, value_length);
807
808          fprintf(stderr, "%s%*sBOOLEAN %d bytes %d\n", prefix, indent, "",
809	          value_length, integer);
810          break;
811
812      case CUPS_ASN1_INTEGER :
813          integer = asn1_get_integer(&buffer, bufend, value_length);
814
815          fprintf(stderr, "%s%*sINTEGER %d bytes %d\n", prefix, indent, "",
816	          value_length, integer);
817          break;
818
819      case CUPS_ASN1_COUNTER :
820          integer = asn1_get_integer(&buffer, bufend, value_length);
821
822          fprintf(stderr, "%s%*sCOUNTER %d bytes %u\n", prefix, indent, "",
823	          value_length, (unsigned)integer);
824          break;
825
826      case CUPS_ASN1_GAUGE :
827          integer = asn1_get_integer(&buffer, bufend, value_length);
828
829          fprintf(stderr, "%s%*sGAUGE %d bytes %u\n", prefix, indent, "",
830	          value_length, (unsigned)integer);
831          break;
832
833      case CUPS_ASN1_TIMETICKS :
834          integer = asn1_get_integer(&buffer, bufend, value_length);
835
836          fprintf(stderr, "%s%*sTIMETICKS %d bytes %u\n", prefix, indent, "",
837	          value_length, (unsigned)integer);
838          break;
839
840      case CUPS_ASN1_OCTET_STRING :
841          fprintf(stderr, "%s%*sOCTET STRING %d bytes \"%s\"\n", prefix,
842	          indent, "", value_length,
843		  asn1_get_string(&buffer, bufend, value_length, string,
844				  sizeof(string)));
845          break;
846
847      case CUPS_ASN1_HEX_STRING :
848	  asn1_get_string(&buffer, bufend, value_length, string,
849			  sizeof(string));
850          fprintf(stderr, "%s%*sHex-STRING %d bytes", prefix,
851	          indent, "", value_length);
852          for (i = 0; i < value_length; i ++)
853	    fprintf(stderr, " %02X", string[i] & 255);
854	  putc('\n', stderr);
855          break;
856
857      case CUPS_ASN1_NULL_VALUE :
858          fprintf(stderr, "%s%*sNULL VALUE %d bytes\n", prefix, indent, "",
859	          value_length);
860
861	  buffer += value_length;
862          break;
863
864      case CUPS_ASN1_OID :
865          integer = asn1_get_oid(&buffer, bufend, value_length, oid,
866	                         CUPS_SNMP_MAX_OID);
867
868          fprintf(stderr, "%s%*sOID %d bytes ", prefix, indent, "",
869	          value_length);
870	  for (i = 0; i < (unsigned)integer; i ++)
871	    fprintf(stderr, ".%d", oid[i]);
872	  putc('\n', stderr);
873          break;
874
875      case CUPS_ASN1_SEQUENCE :
876          fprintf(stderr, "%s%*sSEQUENCE %d bytes\n", prefix, indent, "",
877	          value_length);
878          asn1_debug(prefix, buffer, value_length, indent + 4);
879
880	  buffer += value_length;
881          break;
882
883      case CUPS_ASN1_GET_NEXT_REQUEST :
884          fprintf(stderr, "%s%*sGet-Next-Request-PDU %d bytes\n", prefix,
885	          indent, "", value_length);
886          asn1_debug(prefix, buffer, value_length, indent + 4);
887
888	  buffer += value_length;
889          break;
890
891      case CUPS_ASN1_GET_REQUEST :
892          fprintf(stderr, "%s%*sGet-Request-PDU %d bytes\n", prefix, indent, "",
893	          value_length);
894          asn1_debug(prefix, buffer, value_length, indent + 4);
895
896	  buffer += value_length;
897          break;
898
899      case CUPS_ASN1_GET_RESPONSE :
900          fprintf(stderr, "%s%*sGet-Response-PDU %d bytes\n", prefix, indent,
901	          "", value_length);
902          asn1_debug(prefix, buffer, value_length, indent + 4);
903
904	  buffer += value_length;
905          break;
906
907      default :
908          fprintf(stderr, "%s%*sUNKNOWN(%x) %d bytes\n", prefix, indent, "",
909	          value_type, value_length);
910
911	  buffer += value_length;
912          break;
913    }
914  }
915}
916
917
918/*
919 * 'asn1_decode_snmp()' - Decode a SNMP packet.
920 */
921
922static int				/* O - 0 on success, -1 on error */
923asn1_decode_snmp(unsigned char *buffer,	/* I - Buffer */
924                 size_t        len,	/* I - Size of buffer */
925                 cups_snmp_t   *packet)	/* I - SNMP packet */
926{
927  unsigned char	*bufptr,		/* Pointer into the data */
928		*bufend;		/* End of data */
929  unsigned	length;			/* Length of value */
930
931
932 /*
933  * Initialize the decoding...
934  */
935
936  memset(packet, 0, sizeof(cups_snmp_t));
937  packet->object_name[0] = -1;
938
939  bufptr = buffer;
940  bufend = buffer + len;
941
942  if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_SEQUENCE)
943    snmp_set_error(packet, _("Packet does not start with SEQUENCE"));
944  else if (asn1_get_length(&bufptr, bufend) == 0)
945    snmp_set_error(packet, _("SEQUENCE uses indefinite length"));
946  else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
947    snmp_set_error(packet, _("No version number"));
948  else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
949    snmp_set_error(packet, _("Version uses indefinite length"));
950  else if ((packet->version = asn1_get_integer(&bufptr, bufend, length))
951               != CUPS_SNMP_VERSION_1)
952    snmp_set_error(packet, _("Bad SNMP version number"));
953  else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_OCTET_STRING)
954    snmp_set_error(packet, _("No community name"));
955  else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
956    snmp_set_error(packet, _("Community name uses indefinite length"));
957  else
958  {
959    asn1_get_string(&bufptr, bufend, length, packet->community,
960                    sizeof(packet->community));
961
962    if ((packet->request_type = (cups_asn1_t)asn1_get_type(&bufptr, bufend))
963            != CUPS_ASN1_GET_RESPONSE)
964      snmp_set_error(packet, _("Packet does not contain a Get-Response-PDU"));
965    else if (asn1_get_length(&bufptr, bufend) == 0)
966      snmp_set_error(packet, _("Get-Response-PDU uses indefinite length"));
967    else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
968      snmp_set_error(packet, _("No request-id"));
969    else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
970      snmp_set_error(packet, _("request-id uses indefinite length"));
971    else
972    {
973      packet->request_id = (unsigned)asn1_get_integer(&bufptr, bufend, length);
974
975      if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
976	snmp_set_error(packet, _("No error-status"));
977      else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
978	snmp_set_error(packet, _("error-status uses indefinite length"));
979      else
980      {
981	packet->error_status = asn1_get_integer(&bufptr, bufend, length);
982
983	if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
984	  snmp_set_error(packet, _("No error-index"));
985	else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
986	  snmp_set_error(packet, _("error-index uses indefinite length"));
987	else
988	{
989	  packet->error_index = asn1_get_integer(&bufptr, bufend, length);
990
991          if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_SEQUENCE)
992	    snmp_set_error(packet, _("No variable-bindings SEQUENCE"));
993	  else if (asn1_get_length(&bufptr, bufend) == 0)
994	    snmp_set_error(packet,
995	                   _("variable-bindings uses indefinite length"));
996	  else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_SEQUENCE)
997	    snmp_set_error(packet, _("No VarBind SEQUENCE"));
998	  else if (asn1_get_length(&bufptr, bufend) == 0)
999	    snmp_set_error(packet, _("VarBind uses indefinite length"));
1000	  else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_OID)
1001	    snmp_set_error(packet, _("No name OID"));
1002	  else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
1003	    snmp_set_error(packet, _("Name OID uses indefinite length"));
1004          else
1005	  {
1006	    asn1_get_oid(&bufptr, bufend, length, packet->object_name,
1007	                 CUPS_SNMP_MAX_OID);
1008
1009            packet->object_type = (cups_asn1_t)asn1_get_type(&bufptr, bufend);
1010
1011	    if ((length = asn1_get_length(&bufptr, bufend)) == 0 &&
1012	        packet->object_type != CUPS_ASN1_NULL_VALUE &&
1013	        packet->object_type != CUPS_ASN1_OCTET_STRING)
1014	      snmp_set_error(packet, _("Value uses indefinite length"));
1015	    else
1016	    {
1017	      switch (packet->object_type)
1018	      {
1019	        case CUPS_ASN1_BOOLEAN :
1020		    packet->object_value.boolean =
1021		        asn1_get_integer(&bufptr, bufend, length);
1022	            break;
1023
1024	        case CUPS_ASN1_INTEGER :
1025		    packet->object_value.integer =
1026		        asn1_get_integer(&bufptr, bufend, length);
1027	            break;
1028
1029		case CUPS_ASN1_NULL_VALUE :
1030		    break;
1031
1032	        case CUPS_ASN1_OCTET_STRING :
1033	        case CUPS_ASN1_BIT_STRING :
1034	        case CUPS_ASN1_HEX_STRING :
1035		    packet->object_value.string.num_bytes = length;
1036		    asn1_get_string(&bufptr, bufend, length,
1037		                    (char *)packet->object_value.string.bytes,
1038				    sizeof(packet->object_value.string.bytes));
1039	            break;
1040
1041	        case CUPS_ASN1_OID :
1042		    asn1_get_oid(&bufptr, bufend, length,
1043		                 packet->object_value.oid, CUPS_SNMP_MAX_OID);
1044	            break;
1045
1046	        case CUPS_ASN1_COUNTER :
1047		    packet->object_value.counter =
1048		        asn1_get_integer(&bufptr, bufend, length);
1049	            break;
1050
1051	        case CUPS_ASN1_GAUGE :
1052		    packet->object_value.gauge =
1053		        (unsigned)asn1_get_integer(&bufptr, bufend, length);
1054	            break;
1055
1056	        case CUPS_ASN1_TIMETICKS :
1057		    packet->object_value.timeticks =
1058		        (unsigned)asn1_get_integer(&bufptr, bufend, length);
1059	            break;
1060
1061                default :
1062		    snmp_set_error(packet, _("Unsupported value type"));
1063		    break;
1064	      }
1065	    }
1066          }
1067	}
1068      }
1069    }
1070  }
1071
1072  return (packet->error ? -1 : 0);
1073}
1074
1075
1076/*
1077 * 'asn1_encode_snmp()' - Encode a SNMP packet.
1078 */
1079
1080static int				/* O - Length on success, -1 on error */
1081asn1_encode_snmp(unsigned char *buffer,	/* I - Buffer */
1082                 size_t        bufsize,	/* I - Size of buffer */
1083                 cups_snmp_t   *packet)	/* I - SNMP packet */
1084{
1085  unsigned char	*bufptr;		/* Pointer into buffer */
1086  unsigned	total,			/* Total length */
1087		msglen,			/* Length of entire message */
1088		commlen,		/* Length of community string */
1089		reqlen,			/* Length of request */
1090		listlen,		/* Length of variable list */
1091		varlen,			/* Length of variable */
1092		namelen,		/* Length of object name OID */
1093		valuelen;		/* Length of object value */
1094
1095
1096 /*
1097  * Get the lengths of the community string, OID, and message...
1098  */
1099
1100
1101  namelen = asn1_size_oid(packet->object_name);
1102
1103  switch (packet->object_type)
1104  {
1105    case CUPS_ASN1_NULL_VALUE :
1106        valuelen = 0;
1107	break;
1108
1109    case CUPS_ASN1_BOOLEAN :
1110        valuelen = asn1_size_integer(packet->object_value.boolean);
1111	break;
1112
1113    case CUPS_ASN1_INTEGER :
1114        valuelen = asn1_size_integer(packet->object_value.integer);
1115	break;
1116
1117    case CUPS_ASN1_OCTET_STRING :
1118        valuelen = packet->object_value.string.num_bytes;
1119	break;
1120
1121    case CUPS_ASN1_OID :
1122        valuelen = asn1_size_oid(packet->object_value.oid);
1123	break;
1124
1125    default :
1126        packet->error = "Unknown object type";
1127        return (-1);
1128  }
1129
1130  varlen  = 1 + asn1_size_length(namelen) + namelen +
1131            1 + asn1_size_length(valuelen) + valuelen;
1132  listlen = 1 + asn1_size_length(varlen) + varlen;
1133  reqlen  = 2 + asn1_size_integer((int)packet->request_id) +
1134            2 + asn1_size_integer(packet->error_status) +
1135            2 + asn1_size_integer(packet->error_index) +
1136            1 + asn1_size_length(listlen) + listlen;
1137  commlen = (unsigned)strlen(packet->community);
1138  msglen  = 2 + asn1_size_integer(packet->version) +
1139            1 + asn1_size_length(commlen) + commlen +
1140	    1 + asn1_size_length(reqlen) + reqlen;
1141  total   = 1 + asn1_size_length(msglen) + msglen;
1142
1143  if (total > bufsize)
1144  {
1145    packet->error = "Message too large for buffer";
1146    return (-1);
1147  }
1148
1149 /*
1150  * Then format the message...
1151  */
1152
1153  bufptr = buffer;
1154
1155  *bufptr++ = CUPS_ASN1_SEQUENCE;	/* SNMPv1 message header */
1156  asn1_set_length(&bufptr, msglen);
1157
1158  asn1_set_integer(&bufptr, packet->version);
1159					/* version */
1160
1161  *bufptr++ = CUPS_ASN1_OCTET_STRING;	/* community */
1162  asn1_set_length(&bufptr, commlen);
1163  memcpy(bufptr, packet->community, commlen);
1164  bufptr += commlen;
1165
1166  *bufptr++ = packet->request_type;	/* Get-Request-PDU/Get-Next-Request-PDU */
1167  asn1_set_length(&bufptr, reqlen);
1168
1169  asn1_set_integer(&bufptr, (int)packet->request_id);
1170
1171  asn1_set_integer(&bufptr, packet->error_status);
1172
1173  asn1_set_integer(&bufptr, packet->error_index);
1174
1175  *bufptr++ = CUPS_ASN1_SEQUENCE;	/* variable-bindings */
1176  asn1_set_length(&bufptr, listlen);
1177
1178  *bufptr++ = CUPS_ASN1_SEQUENCE;	/* variable */
1179  asn1_set_length(&bufptr, varlen);
1180
1181  asn1_set_oid(&bufptr, packet->object_name);
1182					/* ObjectName */
1183
1184  switch (packet->object_type)
1185  {
1186    case CUPS_ASN1_NULL_VALUE :
1187	*bufptr++ = CUPS_ASN1_NULL_VALUE;
1188					/* ObjectValue */
1189	*bufptr++ = 0;			/* Length */
1190        break;
1191
1192    case CUPS_ASN1_BOOLEAN :
1193        asn1_set_integer(&bufptr, packet->object_value.boolean);
1194	break;
1195
1196    case CUPS_ASN1_INTEGER :
1197        asn1_set_integer(&bufptr, packet->object_value.integer);
1198	break;
1199
1200    case CUPS_ASN1_OCTET_STRING :
1201        *bufptr++ = CUPS_ASN1_OCTET_STRING;
1202	asn1_set_length(&bufptr, valuelen);
1203	memcpy(bufptr, packet->object_value.string.bytes, valuelen);
1204	bufptr += valuelen;
1205	break;
1206
1207    case CUPS_ASN1_OID :
1208        asn1_set_oid(&bufptr, packet->object_value.oid);
1209	break;
1210
1211    default :
1212        break;
1213  }
1214
1215  return ((int)(bufptr - buffer));
1216}
1217
1218
1219/*
1220 * 'asn1_get_integer()' - Get an integer value.
1221 */
1222
1223static int				/* O  - Integer value */
1224asn1_get_integer(
1225    unsigned char **buffer,		/* IO - Pointer in buffer */
1226    unsigned char *bufend,		/* I  - End of buffer */
1227    unsigned      length)		/* I  - Length of value */
1228{
1229  int	value;				/* Integer value */
1230
1231
1232  if (length > sizeof(int))
1233  {
1234    (*buffer) += length;
1235    return (0);
1236  }
1237
1238  for (value = (**buffer & 0x80) ? -1 : 0;
1239       length > 0 && *buffer < bufend;
1240       length --, (*buffer) ++)
1241    value = (value << 8) | **buffer;
1242
1243  return (value);
1244}
1245
1246
1247/*
1248 * 'asn1_get_length()' - Get a value length.
1249 */
1250
1251static unsigned				/* O  - Length */
1252asn1_get_length(unsigned char **buffer,	/* IO - Pointer in buffer */
1253		unsigned char *bufend)	/* I  - End of buffer */
1254{
1255  unsigned	length;			/* Length */
1256
1257
1258  length = **buffer;
1259  (*buffer) ++;
1260
1261  if (length & 128)
1262  {
1263    int	count;				/* Number of bytes for length */
1264
1265
1266    if ((count = length & 127) > sizeof(unsigned))
1267    {
1268      (*buffer) += count;
1269      return (0);
1270    }
1271
1272    for (length = 0;
1273	 count > 0 && *buffer < bufend;
1274	 count --, (*buffer) ++)
1275      length = (length << 8) | **buffer;
1276  }
1277
1278  return (length);
1279}
1280
1281
1282/*
1283 * 'asn1_get_oid()' - Get an OID value.
1284 */
1285
1286static int				/* O  - Number of OIDs */
1287asn1_get_oid(
1288    unsigned char **buffer,		/* IO - Pointer in buffer */
1289    unsigned char *bufend,		/* I  - End of buffer */
1290    unsigned      length,		/* I  - Length of value */
1291    int           *oid,			/* I  - OID buffer */
1292    int           oidsize)		/* I  - Size of OID buffer */
1293{
1294  unsigned char	*valend;		/* End of value */
1295  int		*oidptr,		/* Current OID */
1296		*oidend;		/* End of OID buffer */
1297  int		number;			/* OID number */
1298
1299
1300  valend = *buffer + length;
1301  oidptr = oid;
1302  oidend = oid + oidsize - 1;
1303
1304  if (valend > bufend)
1305    valend = bufend;
1306
1307  number = asn1_get_packed(buffer, bufend);
1308
1309  if (number < 80)
1310  {
1311    *oidptr++ = number / 40;
1312    number    = number % 40;
1313    *oidptr++ = number;
1314  }
1315  else
1316  {
1317    *oidptr++ = 2;
1318    number    -= 80;
1319    *oidptr++ = number;
1320  }
1321
1322  while (*buffer < valend)
1323  {
1324    number = asn1_get_packed(buffer, bufend);
1325
1326    if (oidptr < oidend)
1327      *oidptr++ = number;
1328  }
1329
1330  *oidptr = -1;
1331
1332  return ((int)(oidptr - oid));
1333}
1334
1335
1336/*
1337 * 'asn1_get_packed()' - Get a packed integer value.
1338 */
1339
1340static int				/* O  - Value */
1341asn1_get_packed(
1342    unsigned char **buffer,		/* IO - Pointer in buffer */
1343    unsigned char *bufend)		/* I  - End of buffer */
1344{
1345  int	value;				/* Value */
1346
1347
1348  value = 0;
1349
1350  while ((**buffer & 128) && *buffer < bufend)
1351  {
1352    value = (value << 7) | (**buffer & 127);
1353    (*buffer) ++;
1354  }
1355
1356  if (*buffer < bufend)
1357  {
1358    value = (value << 7) | **buffer;
1359    (*buffer) ++;
1360  }
1361
1362  return (value);
1363}
1364
1365
1366/*
1367 * 'asn1_get_string()' - Get a string value.
1368 */
1369
1370static char *				/* O  - String */
1371asn1_get_string(
1372    unsigned char **buffer,		/* IO - Pointer in buffer */
1373    unsigned char *bufend,		/* I  - End of buffer */
1374    unsigned      length,		/* I  - Value length */
1375    char          *string,		/* I  - String buffer */
1376    size_t        strsize)		/* I  - String buffer size */
1377{
1378  if (length > (unsigned)(bufend - *buffer))
1379    length = (unsigned)(bufend - *buffer);
1380
1381  if (length < strsize)
1382  {
1383   /*
1384    * String is smaller than the buffer...
1385    */
1386
1387    if (length > 0)
1388      memcpy(string, *buffer, length);
1389
1390    string[length] = '\0';
1391  }
1392  else
1393  {
1394   /*
1395    * String is larger than the buffer...
1396    */
1397
1398    memcpy(string, *buffer, strsize - 1);
1399    string[strsize - 1] = '\0';
1400  }
1401
1402  if (length > 0)
1403    (*buffer) += length;
1404
1405  return (string);
1406}
1407
1408
1409/*
1410 * 'asn1_get_type()' - Get a value type.
1411 */
1412
1413static int				/* O  - Type */
1414asn1_get_type(unsigned char **buffer,	/* IO - Pointer in buffer */
1415	      unsigned char *bufend)	/* I  - End of buffer */
1416{
1417  int	type;				/* Type */
1418
1419
1420  type = **buffer;
1421  (*buffer) ++;
1422
1423  if ((type & 31) == 31)
1424    type = asn1_get_packed(buffer, bufend);
1425
1426  return (type);
1427}
1428
1429
1430/*
1431 * 'asn1_set_integer()' - Set an integer value.
1432 */
1433
1434static void
1435asn1_set_integer(unsigned char **buffer,/* IO - Pointer in buffer */
1436                 int           integer)	/* I  - Integer value */
1437{
1438  **buffer = CUPS_ASN1_INTEGER;
1439  (*buffer) ++;
1440
1441  if (integer > 0x7fffff || integer < -0x800000)
1442  {
1443    **buffer = 4;
1444    (*buffer) ++;
1445    **buffer = (unsigned char)(integer >> 24);
1446    (*buffer) ++;
1447    **buffer = (unsigned char)(integer >> 16);
1448    (*buffer) ++;
1449    **buffer = (unsigned char)(integer >> 8);
1450    (*buffer) ++;
1451    **buffer = (unsigned char)integer;
1452    (*buffer) ++;
1453  }
1454  else if (integer > 0x7fff || integer < -0x8000)
1455  {
1456    **buffer = 3;
1457    (*buffer) ++;
1458    **buffer = (unsigned char)(integer >> 16);
1459    (*buffer) ++;
1460    **buffer = (unsigned char)(integer >> 8);
1461    (*buffer) ++;
1462    **buffer = (unsigned char)integer;
1463    (*buffer) ++;
1464  }
1465  else if (integer > 0x7f || integer < -0x80)
1466  {
1467    **buffer = 2;
1468    (*buffer) ++;
1469    **buffer = (unsigned char)(integer >> 8);
1470    (*buffer) ++;
1471    **buffer = (unsigned char)integer;
1472    (*buffer) ++;
1473  }
1474  else
1475  {
1476    **buffer = 1;
1477    (*buffer) ++;
1478    **buffer = (unsigned char)integer;
1479    (*buffer) ++;
1480  }
1481}
1482
1483
1484/*
1485 * 'asn1_set_length()' - Set a value length.
1486 */
1487
1488static void
1489asn1_set_length(unsigned char **buffer,	/* IO - Pointer in buffer */
1490		unsigned      length)	/* I  - Length value */
1491{
1492  if (length > 255)
1493  {
1494    **buffer = 0x82;			/* 2-byte length */
1495    (*buffer) ++;
1496    **buffer = (unsigned char)(length >> 8);
1497    (*buffer) ++;
1498    **buffer = (unsigned char)length;
1499    (*buffer) ++;
1500  }
1501  else if (length > 127)
1502  {
1503    **buffer = 0x81;			/* 1-byte length */
1504    (*buffer) ++;
1505    **buffer = (unsigned char)length;
1506    (*buffer) ++;
1507  }
1508  else
1509  {
1510    **buffer = (unsigned char)length;	/* Length */
1511    (*buffer) ++;
1512  }
1513}
1514
1515
1516/*
1517 * 'asn1_set_oid()' - Set an OID value.
1518 */
1519
1520static void
1521asn1_set_oid(unsigned char **buffer,	/* IO - Pointer in buffer */
1522             const int     *oid)	/* I  - OID value */
1523{
1524  **buffer = CUPS_ASN1_OID;
1525  (*buffer) ++;
1526
1527  asn1_set_length(buffer, asn1_size_oid(oid));
1528
1529  if (oid[1] < 0)
1530  {
1531    asn1_set_packed(buffer, oid[0] * 40);
1532    return;
1533  }
1534
1535  asn1_set_packed(buffer, oid[0] * 40 + oid[1]);
1536
1537  for (oid += 2; *oid >= 0; oid ++)
1538    asn1_set_packed(buffer, *oid);
1539}
1540
1541
1542/*
1543 * 'asn1_set_packed()' - Set a packed integer value.
1544 */
1545
1546static void
1547asn1_set_packed(unsigned char **buffer,	/* IO - Pointer in buffer */
1548		int           integer)	/* I  - Integer value */
1549{
1550  if (integer > 0xfffffff)
1551  {
1552    **buffer = ((integer >> 28) & 0x7f) | 0x80;
1553    (*buffer) ++;
1554  }
1555
1556  if (integer > 0x1fffff)
1557  {
1558    **buffer = ((integer >> 21) & 0x7f) | 0x80;
1559    (*buffer) ++;
1560  }
1561
1562  if (integer > 0x3fff)
1563  {
1564    **buffer = ((integer >> 14) & 0x7f) | 0x80;
1565    (*buffer) ++;
1566  }
1567
1568  if (integer > 0x7f)
1569  {
1570    **buffer = ((integer >> 7) & 0x7f) | 0x80;
1571    (*buffer) ++;
1572  }
1573
1574  **buffer = integer & 0x7f;
1575  (*buffer) ++;
1576}
1577
1578
1579/*
1580 * 'asn1_size_integer()' - Figure out the number of bytes needed for an
1581 *                         integer value.
1582 */
1583
1584static unsigned				/* O - Size in bytes */
1585asn1_size_integer(int integer)		/* I - Integer value */
1586{
1587  if (integer > 0x7fffff || integer < -0x800000)
1588    return (4);
1589  else if (integer > 0x7fff || integer < -0x8000)
1590    return (3);
1591  else if (integer > 0x7f || integer < -0x80)
1592    return (2);
1593  else
1594    return (1);
1595}
1596
1597
1598/*
1599 * 'asn1_size_length()' - Figure out the number of bytes needed for a
1600 *                        length value.
1601 */
1602
1603static unsigned				/* O - Size in bytes */
1604asn1_size_length(unsigned length)	/* I - Length value */
1605{
1606  if (length > 0xff)
1607    return (3);
1608  else if (length > 0x7f)
1609    return (2);
1610  else
1611    return (1);
1612}
1613
1614
1615/*
1616 * 'asn1_size_oid()' - Figure out the numebr of bytes needed for an
1617 *                     OID value.
1618 */
1619
1620static unsigned				/* O - Size in bytes */
1621asn1_size_oid(const int *oid)		/* I - OID value */
1622{
1623  unsigned	length;			/* Length of value */
1624
1625
1626  if (oid[1] < 0)
1627    return (asn1_size_packed(oid[0] * 40));
1628
1629  for (length = asn1_size_packed(oid[0] * 40 + oid[1]), oid += 2;
1630       *oid >= 0;
1631       oid ++)
1632    length += asn1_size_packed(*oid);
1633
1634  return (length);
1635}
1636
1637
1638/*
1639 * 'asn1_size_packed()' - Figure out the number of bytes needed for a
1640 *                        packed integer value.
1641 */
1642
1643static unsigned				/* O - Size in bytes */
1644asn1_size_packed(int integer)		/* I - Integer value */
1645{
1646  if (integer > 0xfffffff)
1647    return (5);
1648  else if (integer > 0x1fffff)
1649    return (4);
1650  else if (integer > 0x3fff)
1651    return (3);
1652  else if (integer > 0x7f)
1653    return (2);
1654  else
1655    return (1);
1656}
1657
1658
1659/*
1660 * 'snmp_set_error()' - Set the localized error for a packet.
1661 */
1662
1663static void
1664snmp_set_error(cups_snmp_t *packet,	/* I - Packet */
1665               const char *message)	/* I - Error message */
1666{
1667  _cups_globals_t *cg = _cupsGlobals();	/* Global data */
1668
1669
1670  if (!cg->lang_default)
1671    cg->lang_default = cupsLangDefault();
1672
1673  packet->error = _cupsLangString(cg->lang_default, message);
1674}
1675