cups/snmp.c

   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
  14 /*
  15  * Include necessary headers.
  16  */
  17
  18 #include "cups-private.h"
  19 #include "snmp-private.h"
  20 #ifdef HAVE_POLL
  21 #  include <poll.h>
  22 #endif /* HAVE_POLL */
  23
  24
  25 /*
  26  * Local functions...
  27  */
  28
  29 static void             asn1_debug(const char *prefix, unsigned char *buffer,
  30                                    size_t len, int indent);
  31 static int              asn1_decode_snmp(unsigned char *buffer, size_t len,
  32                                          cups_snmp_t *packet);
  33 static int              asn1_encode_snmp(unsigned char *buffer, size_t len,
  34                                          cups_snmp_t *packet);
  35 static int              asn1_get_integer(unsigned char **buffer,
  36                                          unsigned char *bufend,
  37                                          unsigned length);
  38 static int              asn1_get_oid(unsigned char **buffer,
  39                                      unsigned char *bufend,
  40                                      unsigned length, int *oid, int oidsize);
  41 static int              asn1_get_packed(unsigned char **buffer,
  42                                         unsigned char *bufend);
  43 static char             *asn1_get_string(unsigned char **buffer,
  44                                          unsigned char *bufend,
  45                                          unsigned length, char *string,
  46                                          size_t strsize);
  47 static unsigned         asn1_get_length(unsigned char **buffer,
  48                                         unsigned char *bufend);
  49 static int              asn1_get_type(unsigned char **buffer,
  50                                       unsigned char *bufend);
  51 static void             asn1_set_integer(unsigned char **buffer,
  52                                          int integer);
  53 static void             asn1_set_length(unsigned char **buffer,
  54                                         unsigned length);
  55 static void             asn1_set_oid(unsigned char **buffer,
  56                                      const int *oid);
  57 static void             asn1_set_packed(unsigned char **buffer,
  58                                         int integer);
  59 static unsigned         asn1_size_integer(int integer);
  60 static unsigned         asn1_size_length(unsigned length);
  61 static unsigned         asn1_size_oid(const int *oid);
  62 static unsigned         asn1_size_packed(int integer);
  63 static void             snmp_set_error(cups_snmp_t *packet,
  64                                        const char *message);
  65
  66
  67 /*
  68  * '_cupsSNMPClose()' - Close a SNMP socket.
  69  */
  70
  71 void
  72 _cupsSNMPClose(int fd)                  /* I - SNMP socket file descriptor */
  73 {
  74   DEBUG_printf(("4_cupsSNMPClose(fd=%d)", fd));
  75
  76   httpAddrClose(NULL, fd);
  77 }
  78
  79
  80 /*
  81  * '_cupsSNMPCopyOID()' - Copy an OID.
  82  *
  83  * The array pointed to by "src" is terminated by the value -1.
  84  */
  85
  86 int *                                   /* O - New OID */
  87 _cupsSNMPCopyOID(int       *dst,        /* I - Destination OID */
  88                  const int *src,        /* I - Source OID */
  89                  int       dstsize)     /* I - Number of integers in dst */
  90 {
  91   int   i;                              /* Looping var */
  92
  93
  94   DEBUG_printf(("4_cupsSNMPCopyOID(dst=%p, src=%p, dstsize=%d)", dst, src,
  95                 dstsize));
  96
  97   for (i = 0, dstsize --; src[i] >= 0 && i < dstsize; i ++)
  98     dst[i] = src[i];
  99
 100   dst[i] = -1;
 101
 102   return (dst);
 103 }
 104
 105
 106 /*
 107  * '_cupsSNMPDefaultCommunity()' - Get the default SNMP community name.
 108  *
 109  * The default community name is the first community name found in the
 110  * snmp.conf file. If no community name is defined there, "public" is used.
 111  */
 112
 113 const char *                            /* O - Default community name */
 114 _cupsSNMPDefaultCommunity(void)
 115 {
 116   cups_file_t   *fp;                    /* snmp.conf file */
 117   char          line[1024],             /* Line from file */
 118                 *value;                 /* Value from file */
 119   int           linenum;                /* Line number in file */
 120   _cups_globals_t *cg = _cupsGlobals(); /* Global data */
 121
 122
 123   DEBUG_puts("4_cupsSNMPDefaultCommunity()");
 124
 125   if (!cg->snmp_community[0])
 126   {
 127     strlcpy(cg->snmp_community, "public", sizeof(cg->snmp_community));
 128
 129     snprintf(line, sizeof(line), "%s/snmp.conf", cg->cups_serverroot);
 130     if ((fp = cupsFileOpen(line, "r")) != NULL)
 131     {
 132       linenum = 0;
 133       while (cupsFileGetConf(fp, line, sizeof(line), &value, &linenum))
 134         if (!_cups_strcasecmp(line, "Community") && value)
 135         {
 136           strlcpy(cg->snmp_community, value, sizeof(cg->snmp_community));
 137           break;
 138         }
 139
 140       cupsFileClose(fp);
 141     }
 142   }
 143
 144   DEBUG_printf(("5_cupsSNMPDefaultCommunity: Returning \"%s\"",
 145                 cg->snmp_community));
 146
 147   return (cg->snmp_community);
 148 }
 149
 150
 151 /*
 152  * '_cupsSNMPIsOID()' - Test whether a SNMP response contains the specified OID.
 153  *
 154  * The array pointed to by "oid" is terminated by the value -1.
 155  */
 156
 157 int                                     /* O - 1 if equal, 0 if not equal */
 158 _cupsSNMPIsOID(cups_snmp_t *packet,     /* I - Response packet */
 159                const int   *oid)        /* I - OID */
 160 {
 161   int   i;                              /* Looping var */
 162
 163
 164  /*
 165   * Range check input...
 166   */
 167
 168   DEBUG_printf(("4_cupsSNMPIsOID(packet=%p, oid=%p)", packet, oid));
 169
 170   if (!packet || !oid)
 171   {
 172     DEBUG_puts("5_cupsSNMPIsOID: Returning 0");
 173
 174     return (0);
 175   }
 176
 177  /*
 178   * Compare OIDs...
 179   */
 180
 181   for (i = 0;
 182        i < CUPS_SNMP_MAX_OID && oid[i] >= 0 && packet->object_name[i] >= 0;
 183        i ++)
 184     if (oid[i] != packet->object_name[i])
 185     {
 186       DEBUG_puts("5_cupsSNMPIsOID: Returning 0");
 187
 188       return (0);
 189     }
 190
 191   DEBUG_printf(("5_cupsSNMPIsOID: Returning %d",
 192                 i < CUPS_SNMP_MAX_OID && oid[i] == packet->object_name[i]));
 193
 194   return (i < CUPS_SNMP_MAX_OID && oid[i] == packet->object_name[i]);
 195 }
 196
 197
 198 /*
 199  * '_cupsSNMPIsOIDPrefixed()' - Test whether a SNMP response uses the specified
 200  *                              OID prefix.
 201  *
 202  * The array pointed to by "prefix" is terminated by the value -1.
 203  */
 204
 205 int                                     /* O - 1 if prefixed, 0 if not prefixed */
 206 _cupsSNMPIsOIDPrefixed(
 207     cups_snmp_t *packet,                /* I - Response packet */
 208     const int   *prefix)                /* I - OID prefix */
 209 {
 210   int   i;                              /* Looping var */
 211
 212
 213  /*
 214   * Range check input...
 215   */
 216
 217   DEBUG_printf(("4_cupsSNMPIsOIDPrefixed(packet=%p, prefix=%p)", packet,
 218                 prefix));
 219
 220   if (!packet || !prefix)
 221   {
 222     DEBUG_puts("5_cupsSNMPIsOIDPrefixed: Returning 0");
 223
 224     return (0);
 225   }
 226
 227  /*
 228   * Compare OIDs...
 229   */
 230
 231   for (i = 0;
 232        i < CUPS_SNMP_MAX_OID && prefix[i] >= 0 && packet->object_name[i] >= 0;
 233        i ++)
 234     if (prefix[i] != packet->object_name[i])
 235     {
 236       DEBUG_puts("5_cupsSNMPIsOIDPrefixed: Returning 0");
 237
 238       return (0);
 239     }
 240
 241   DEBUG_printf(("5_cupsSNMPIsOIDPrefixed: Returning %d",
 242                 i < CUPS_SNMP_MAX_OID));
 243
 244   return (i < CUPS_SNMP_MAX_OID);
 245 }
 246
 247
 248 /*
 249  * '_cupsSNMPOIDToString()' - Convert an OID to a string.
 250  */
 251
 252
 253 char *                                  /* O - New string or @code NULL@ on error */
 254 _cupsSNMPOIDToString(const int *src,    /* I - OID */
 255                      char      *dst,    /* I - String buffer */
 256                      size_t    dstsize) /* I - Size of string buffer */
 257 {
 258   char  *dstptr,                        /* Pointer into string buffer */
 259         *dstend;                        /* End of string buffer */
 260
 261
 262   DEBUG_printf(("4_cupsSNMPOIDToString(src=%p, dst=%p, dstsize=" CUPS_LLFMT ")",
 263                 src, dst, CUPS_LLCAST dstsize));
 264
 265  /*
 266   * Range check input...
 267   */
 268
 269   if (!src || !dst || dstsize < 4)
 270     return (NULL);
 271
 272  /*
 273   * Loop through the OID array and build a string...
 274   */
 275
 276   for (dstptr = dst, dstend = dstptr + dstsize - 1;
 277        *src >= 0 && dstptr < dstend;
 278        src ++, dstptr += strlen(dstptr))
 279     snprintf(dstptr, (size_t)(dstend - dstptr + 1), ".%d", *src);
 280
 281   if (*src >= 0)
 282     return (NULL);
 283   else
 284     return (dst);
 285 }
 286
 287
 288 /*
 289  * '_cupsSNMPOpen()' - Open a SNMP socket.
 290  */
 291
 292 int                                     /* O - SNMP socket file descriptor */
 293 _cupsSNMPOpen(int family)               /* I - Address family - @code AF_INET@ or @code AF_INET6@ */
 294 {
 295   int           fd;                     /* SNMP socket file descriptor */
 296   int           val;                    /* Socket option value */
 297
 298
 299  /*
 300   * Create the SNMP socket...
 301   */
 302
 303   DEBUG_printf(("4_cupsSNMPOpen(family=%d)", family));
 304
 305   if ((fd = socket(family, SOCK_DGRAM, 0)) < 0)
 306   {
 307     DEBUG_printf(("5_cupsSNMPOpen: Returning -1 (%s)", strerror(errno)));
 308
 309     return (-1);
 310   }
 311
 312  /*
 313   * Set the "broadcast" flag...
 314   */
 315
 316   val = 1;
 317
 318   if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, CUPS_SOCAST &val, sizeof(val)))
 319   {
 320     DEBUG_printf(("5_cupsSNMPOpen: Returning -1 (%s)", strerror(errno)));
 321
 322     close(fd);
 323
 324     return (-1);
 325   }
 326
 327   DEBUG_printf(("5_cupsSNMPOpen: Returning %d", fd));
 328
 329   return (fd);
 330 }
 331
 332
 333 /*
 334  * '_cupsSNMPRead()' - Read and parse a SNMP response.
 335  *
 336  * If "timeout" is negative, @code _cupsSNMPRead@ will wait for a response
 337  * indefinitely.
 338  */
 339
 340 cups_snmp_t *                           /* O - SNMP packet or @code NULL@ if none */
 341 _cupsSNMPRead(int         fd,           /* I - SNMP socket file descriptor */
 342               cups_snmp_t *packet,      /* I - SNMP packet buffer */
 343               double      timeout)      /* I - Timeout in seconds */
 344 {
 345   unsigned char buffer[CUPS_SNMP_MAX_PACKET];
 346                                         /* Data packet */
 347   ssize_t       bytes;                  /* Number of bytes received */
 348   socklen_t     addrlen;                /* Source address length */
 349   http_addr_t   address;                /* Source address */
 350
 351
 352  /*
 353   * Range check input...
 354   */
 355
 356   DEBUG_printf(("4_cupsSNMPRead(fd=%d, packet=%p, timeout=%.1f)", fd, packet,
 357                 timeout));
 358
 359   if (fd < 0 || !packet)
 360   {
 361     DEBUG_puts("5_cupsSNMPRead: Returning NULL");
 362
 363     return (NULL);
 364   }
 365
 366  /*
 367   * Optionally wait for a response...
 368   */
 369
 370   if (timeout >= 0.0)
 371   {
 372     int                 ready;          /* Data ready on socket? */
 373 #ifdef HAVE_POLL
 374     struct pollfd       pfd;            /* Polled file descriptor */
 375
 376     pfd.fd     = fd;
 377     pfd.events = POLLIN;
 378
 379     while ((ready = poll(&pfd, 1, (int)(timeout * 1000.0))) < 0 &&
 380            (errno == EINTR || errno == EAGAIN));
 381
 382 #else
 383     fd_set              input_set;      /* select() input set */
 384     struct timeval      stimeout;       /* select() timeout */
 385
 386     do
 387     {
 388       FD_ZERO(&input_set);
 389       FD_SET(fd, &input_set);
 390
 391       stimeout.tv_sec  = (int)timeout;
 392       stimeout.tv_usec = (int)((timeout - stimeout.tv_sec) * 1000000);
 393
 394       ready = select(fd + 1, &input_set, NULL, NULL, &stimeout);
 395     }
 396 #  ifdef WIN32
 397     while (ready < 0 && WSAGetLastError() == WSAEINTR);
 398 #  else
 399     while (ready < 0 && (errno == EINTR || errno == EAGAIN));
 400 #  endif /* WIN32 */
 401 #endif /* HAVE_POLL */
 402
 403    /*
 404     * If we don't have any data ready, return right away...
 405     */
 406
 407     if (ready <= 0)
 408     {
 409       DEBUG_puts("5_cupsSNMPRead: Returning NULL (timeout)");
 410
 411       return (NULL);
 412     }
 413   }
 414
 415  /*
 416   * Read the response data...
 417   */
 418
 419   addrlen = sizeof(address);
 420
 421   if ((bytes = recvfrom(fd, buffer, sizeof(buffer), 0, (void *)&address,
 422                         &addrlen)) < 0)
 423   {
 424     DEBUG_printf(("5_cupsSNMPRead: Returning NULL (%s)", strerror(errno)));
 425
 426     return (NULL);
 427   }
 428
 429  /*
 430   * Look for the response status code in the SNMP message header...
 431   */
 432
 433   asn1_debug("DEBUG: IN ", buffer, (size_t)bytes, 0);
 434
 435   asn1_decode_snmp(buffer, (size_t)bytes, packet);
 436
 437   memcpy(&(packet->address), &address, sizeof(packet->address));
 438
 439  /*
 440   * Return decoded data packet...
 441   */
 442
 443   DEBUG_puts("5_cupsSNMPRead: Returning packet");
 444
 445   return (packet);
 446 }
 447
 448
 449 /*
 450  * '_cupsSNMPSetDebug()' - Enable/disable debug logging to stderr.
 451  */
 452
 453 void
 454 _cupsSNMPSetDebug(int level)            /* I - 1 to enable debug output, 0 otherwise */
 455 {
 456   _cups_globals_t *cg = _cupsGlobals(); /* Global data */
 457
 458
 459   DEBUG_printf(("4_cupsSNMPSetDebug(level=%d)", level));
 460
 461   cg->snmp_debug = level;
 462 }
 463
 464
 465 /*
 466  * '_cupsSNMPStringToOID()' - Convert a numeric OID string to an OID array.
 467  *
 468  * This function converts a string of the form ".N.N.N.N.N" to the
 469  * corresponding OID array terminated by -1.
 470  *
 471  * @code NULL@ is returned if the array is not large enough or the string is
 472  * not a valid OID number.
 473  */
 474
 475 int *                                   /* O - Pointer to OID array or @code NULL@ on error */
 476 _cupsSNMPStringToOID(const char *src,   /* I - OID string */
 477                      int        *dst,   /* I - OID array */
 478                      int        dstsize)/* I - Number of integers in OID array */
 479 {
 480   int   *dstptr,                        /* Pointer into OID array */
 481         *dstend;                        /* End of OID array */
 482
 483
 484   DEBUG_printf(("4_cupsSNMPStringToOID(src=\"%s\", dst=%p, dstsize=%d)",
 485                 src, dst, dstsize));
 486
 487  /*
 488   * Range check input...
 489   */
 490
 491   if (!src || !dst || dstsize < 2)
 492     return (NULL);
 493
 494  /*
 495   * Skip leading "."...
 496   */
 497
 498   if (*src == '.')
 499     src ++;
 500
 501  /*
 502   * Loop to the end of the string...
 503   */
 504
 505   for (dstend = dst + dstsize - 1, dstptr = dst, *dstptr = 0;
 506        *src && dstptr < dstend;
 507        src ++)
 508   {
 509     if (*src == '.')
 510     {
 511       dstptr ++;
 512       *dstptr = 0;
 513     }
 514     else if (isdigit(*src & 255))
 515       *dstptr = *dstptr * 10 + *src - '0';
 516     else
 517       break;
 518   }
 519
 520   if (*src)
 521     return (NULL);
 522
 523  /*
 524   * Terminate the end of the OID array and return...
 525   */
 526
 527   dstptr[1] = -1;
 528
 529   return (dst);
 530 }
 531
 532
 533 /*
 534  * '_cupsSNMPWalk()' - Enumerate a group of OIDs.
 535  *
 536  * This function queries all of the OIDs with the specified OID prefix,
 537  * calling the "cb" function for every response that is received.
 538  *
 539  * The array pointed to by "prefix" is terminated by the value -1.
 540  *
 541  * If "timeout" is negative, @code _cupsSNMPWalk@ will wait for a response
 542  * indefinitely.
 543  */
 544
 545 int                                     /* O - Number of OIDs found or -1 on error */
 546 _cupsSNMPWalk(int            fd,        /* I - SNMP socket */
 547               http_addr_t    *address,  /* I - Address to query */
 548               int            version,   /* I - SNMP version */
 549               const char     *community,/* I - Community name */
 550               const int      *prefix,   /* I - OID prefix */
 551               double         timeout,   /* I - Timeout for each response in seconds */
 552               cups_snmp_cb_t cb,        /* I - Function to call for each response */
 553               void           *data)     /* I - User data pointer that is passed to the callback function */
 554 {
 555   int           count = 0;              /* Number of OIDs found */
 556   unsigned      request_id = 0;         /* Current request ID */
 557   cups_snmp_t   packet;                 /* Current response packet */
 558   int           lastoid[CUPS_SNMP_MAX_OID];
 559                                         /* Last OID we got */
 560
 561
 562  /*
 563   * Range check input...
 564   */
 565
 566   DEBUG_printf(("4_cupsSNMPWalk(fd=%d, address=%p, version=%d, "
 567                 "community=\"%s\", prefix=%p, timeout=%.1f, cb=%p, data=%p)",
 568                 fd, address, version, community, prefix, timeout, cb, data));
 569
 570   if (fd < 0 || !address || version != CUPS_SNMP_VERSION_1 || !community ||
 571       !prefix || !cb)
 572   {
 573     DEBUG_puts("5_cupsSNMPWalk: Returning -1");
 574
 575     return (-1);
 576   }
 577
 578  /*
 579   * Copy the OID prefix and then loop until we have no more OIDs...
 580   */
 581
 582   _cupsSNMPCopyOID(packet.object_name, prefix, CUPS_SNMP_MAX_OID);
 583   lastoid[0] = -1;
 584
 585   for (;;)
 586   {
 587     request_id ++;
 588
 589     if (!_cupsSNMPWrite(fd, address, version, community,
 590                         CUPS_ASN1_GET_NEXT_REQUEST, request_id,
 591                         packet.object_name))
 592     {
 593       DEBUG_puts("5_cupsSNMPWalk: Returning -1");
 594
 595       return (-1);
 596     }
 597
 598     if (!_cupsSNMPRead(fd, &packet, timeout))
 599     {
 600       DEBUG_puts("5_cupsSNMPWalk: Returning -1");
 601
 602       return (-1);
 603     }
 604
 605     if (!_cupsSNMPIsOIDPrefixed(&packet, prefix) ||
 606         _cupsSNMPIsOID(&packet, lastoid))
 607     {
 608       DEBUG_printf(("5_cupsSNMPWalk: Returning %d", count));
 609
 610       return (count);
 611     }
 612
 613     if (packet.error || packet.error_status)
 614     {
 615       DEBUG_printf(("5_cupsSNMPWalk: Returning %d", count > 0 ? count : -1));
 616
 617       return (count > 0 ? count : -1);
 618     }
 619
 620     _cupsSNMPCopyOID(lastoid, packet.object_name, CUPS_SNMP_MAX_OID);
 621
 622     count ++;
 623
 624     (*cb)(&packet, data);
 625   }
 626 }
 627
 628
 629 /*
 630  * '_cupsSNMPWrite()' - Send an SNMP query packet.
 631  *
 632  * The array pointed to by "oid" is terminated by the value -1.
 633  */
 634
 635 int                                     /* O - 1 on success, 0 on error */
 636 _cupsSNMPWrite(
 637     int            fd,                  /* I - SNMP socket */
 638     http_addr_t    *address,            /* I - Address to send to */
 639     int            version,             /* I - SNMP version */
 640     const char     *community,          /* I - Community name */
 641     cups_asn1_t    request_type,        /* I - Request type */
 642     const unsigned request_id,          /* I - Request ID */
 643     const int      *oid)                /* I - OID */
 644 {
 645   int           i;                      /* Looping var */
 646   cups_snmp_t   packet;                 /* SNMP message packet */
 647   unsigned char buffer[CUPS_SNMP_MAX_PACKET];
 648                                         /* SNMP message buffer */
 649   ssize_t       bytes;                  /* Size of message */
 650   http_addr_t   temp;                   /* Copy of address */
 651
 652
 653  /*
 654   * Range check input...
 655   */
 656
 657   DEBUG_printf(("4_cupsSNMPWrite(fd=%d, address=%p, version=%d, "
 658                 "community=\"%s\", request_type=%d, request_id=%u, oid=%p)",
 659                 fd, address, version, community, request_type, request_id, oid));
 660
 661   if (fd < 0 || !address || version != CUPS_SNMP_VERSION_1 || !community ||
 662       (request_type != CUPS_ASN1_GET_REQUEST &&
 663        request_type != CUPS_ASN1_GET_NEXT_REQUEST) || request_id < 1 || !oid)
 664   {
 665     DEBUG_puts("5_cupsSNMPWrite: Returning 0 (bad arguments)");
 666
 667     return (0);
 668   }
 669
 670  /*
 671   * Create the SNMP message...
 672   */
 673
 674   memset(&packet, 0, sizeof(packet));
 675
 676   packet.version      = version;
 677   packet.request_type = request_type;
 678   packet.request_id   = request_id;
 679   packet.object_type  = CUPS_ASN1_NULL_VALUE;
 680
 681   strlcpy(packet.community, community, sizeof(packet.community));
 682
 683   for (i = 0; oid[i] >= 0 && i < (CUPS_SNMP_MAX_OID - 1); i ++)
 684     packet.object_name[i] = oid[i];
 685   packet.object_name[i] = -1;
 686
 687   if (oid[i] >= 0)
 688   {
 689     DEBUG_puts("5_cupsSNMPWrite: Returning 0 (OID too big)");
 690
 691     errno = E2BIG;
 692     return (0);
 693   }
 694
 695   bytes = asn1_encode_snmp(buffer, sizeof(buffer), &packet);
 696
 697   if (bytes < 0)
 698   {
 699     DEBUG_puts("5_cupsSNMPWrite: Returning 0 (request too big)");
 700
 701     errno = E2BIG;
 702     return (0);
 703   }
 704
 705   asn1_debug("DEBUG: OUT ", buffer, (size_t)bytes, 0);
 706
 707  /*
 708   * Send the message...
 709   */
 710
 711   temp = *address;
 712
 713   _httpAddrSetPort(&temp, CUPS_SNMP_PORT);
 714
 715   return (sendto(fd, buffer, (size_t)bytes, 0, (void *)&temp, (socklen_t)httpAddrLength(&temp)) == bytes);
 716 }
 717
 718
 719 /*
 720  * 'asn1_debug()' - Decode an ASN1-encoded message.
 721  */
 722
 723 static void
 724 asn1_debug(const char    *prefix,       /* I - Prefix string */
 725            unsigned char *buffer,       /* I - Buffer */
 726            size_t        len,           /* I - Length of buffer */
 727            int           indent)        /* I - Indentation */
 728 {
 729   size_t        i;                      /* Looping var */
 730   unsigned char *bufend;                /* End of buffer */
 731   int           integer;                /* Number value */
 732   int           oid[CUPS_SNMP_MAX_OID]; /* OID value */
 733   char          string[CUPS_SNMP_MAX_STRING];
 734                                         /* String value */
 735   unsigned char value_type;             /* Type of value */
 736   unsigned      value_length;           /* Length of value */
 737   _cups_globals_t *cg = _cupsGlobals(); /* Global data */
 738
 739
 740 #ifdef __clang_analyzer__ /* Suppress bogus clang error */
 741   memset(string, 0, sizeof(string));
 742 #endif /* __clang_analyzer__ */
 743
 744   if (cg->snmp_debug <= 0)
 745     return;
 746
 747   if (cg->snmp_debug > 1 && indent == 0)
 748   {
 749    /*
 750     * Do a hex dump of the packet...
 751     */
 752
 753     size_t j;
 754
 755     fprintf(stderr, "%sHex Dump (%d bytes):\n", prefix, (int)len);
 756
 757     for (i = 0; i < len; i += 16)
 758     {
 759       fprintf(stderr, "%s%04x:", prefix, (unsigned)i);
 760
 761       for (j = 0; j < 16 && (i + j) < len; j ++)
 762       {
 763         if (j && !(j & 3))
 764           fprintf(stderr, "  %02x", buffer[i + j]);
 765         else
 766           fprintf(stderr, " %02x", buffer[i + j]);
 767       }
 768
 769       while (j < 16)
 770       {
 771         if (j && !(j & 3))
 772           fputs("    ", stderr);
 773         else
 774           fputs("   ", stderr);
 775
 776         j ++;
 777       }
 778
 779       fputs("    ", stderr);
 780
 781       for (j = 0; j < 16 && (i + j) < len; j ++)
 782         if (buffer[i + j] < ' ' || buffer[i + j] >= 0x7f)
 783           putc('.', stderr);
 784         else
 785           putc(buffer[i + j], stderr);
 786
 787       putc('\n', stderr);
 788     }
 789   }
 790
 791   if (indent == 0)
 792     fprintf(stderr, "%sMessage:\n", prefix);
 793
 794   bufend = buffer + len;
 795
 796   while (buffer < bufend)
 797   {
 798    /*
 799     * Get value type...
 800     */
 801
 802     value_type   = (unsigned char)asn1_get_type(&buffer, bufend);
 803     value_length = asn1_get_length(&buffer, bufend);
 804
 805     switch (value_type)
 806     {
 807       case CUPS_ASN1_BOOLEAN :
 808           integer = asn1_get_integer(&buffer, bufend, value_length);
 809
 810           fprintf(stderr, "%s%*sBOOLEAN %d bytes %d\n", prefix, indent, "",
 811                   value_length, integer);
 812           break;
 813
 814       case CUPS_ASN1_INTEGER :
 815           integer = asn1_get_integer(&buffer, bufend, value_length);
 816
 817           fprintf(stderr, "%s%*sINTEGER %d bytes %d\n", prefix, indent, "",
 818                   value_length, integer);
 819           break;
 820
 821       case CUPS_ASN1_COUNTER :
 822           integer = asn1_get_integer(&buffer, bufend, value_length);
 823
 824           fprintf(stderr, "%s%*sCOUNTER %d bytes %u\n", prefix, indent, "",
 825                   value_length, (unsigned)integer);
 826           break;
 827
 828       case CUPS_ASN1_GAUGE :
 829           integer = asn1_get_integer(&buffer, bufend, value_length);
 830
 831           fprintf(stderr, "%s%*sGAUGE %d bytes %u\n", prefix, indent, "",
 832                   value_length, (unsigned)integer);
 833           break;
 834
 835       case CUPS_ASN1_TIMETICKS :
 836           integer = asn1_get_integer(&buffer, bufend, value_length);
 837
 838           fprintf(stderr, "%s%*sTIMETICKS %d bytes %u\n", prefix, indent, "",
 839                   value_length, (unsigned)integer);
 840           break;
 841
 842       case CUPS_ASN1_OCTET_STRING :
 843           fprintf(stderr, "%s%*sOCTET STRING %d bytes \"%s\"\n", prefix,
 844                   indent, "", value_length,
 845                   asn1_get_string(&buffer, bufend, value_length, string,
 846                                   sizeof(string)));
 847           break;
 848
 849       case CUPS_ASN1_HEX_STRING :
 850           asn1_get_string(&buffer, bufend, value_length, string,
 851                           sizeof(string));
 852           fprintf(stderr, "%s%*sHex-STRING %d bytes", prefix,
 853                   indent, "", value_length);
 854           for (i = 0; i < value_length; i ++)
 855             fprintf(stderr, " %02X", string[i] & 255);
 856           putc('\n', stderr);
 857           break;
 858
 859       case CUPS_ASN1_NULL_VALUE :
 860           fprintf(stderr, "%s%*sNULL VALUE %d bytes\n", prefix, indent, "",
 861                   value_length);
 862
 863           buffer += value_length;
 864           break;
 865
 866       case CUPS_ASN1_OID :
 867           integer = asn1_get_oid(&buffer, bufend, value_length, oid,
 868                                  CUPS_SNMP_MAX_OID);
 869
 870           fprintf(stderr, "%s%*sOID %d bytes ", prefix, indent, "",
 871                   value_length);
 872           for (i = 0; i < (unsigned)integer; i ++)
 873             fprintf(stderr, ".%d", oid[i]);
 874           putc('\n', stderr);
 875           break;
 876
 877       case CUPS_ASN1_SEQUENCE :
 878           fprintf(stderr, "%s%*sSEQUENCE %d bytes\n", prefix, indent, "",
 879                   value_length);
 880           asn1_debug(prefix, buffer, value_length, indent + 4);
 881
 882           buffer += value_length;
 883           break;
 884
 885       case CUPS_ASN1_GET_NEXT_REQUEST :
 886           fprintf(stderr, "%s%*sGet-Next-Request-PDU %d bytes\n", prefix,
 887                   indent, "", value_length);
 888           asn1_debug(prefix, buffer, value_length, indent + 4);
 889
 890           buffer += value_length;
 891           break;
 892
 893       case CUPS_ASN1_GET_REQUEST :
 894           fprintf(stderr, "%s%*sGet-Request-PDU %d bytes\n", prefix, indent, "",
 895                   value_length);
 896           asn1_debug(prefix, buffer, value_length, indent + 4);
 897
 898           buffer += value_length;
 899           break;
 900
 901       case CUPS_ASN1_GET_RESPONSE :
 902           fprintf(stderr, "%s%*sGet-Response-PDU %d bytes\n", prefix, indent,
 903                   "", value_length);
 904           asn1_debug(prefix, buffer, value_length, indent + 4);
 905
 906           buffer += value_length;
 907           break;
 908
 909       default :
 910           fprintf(stderr, "%s%*sUNKNOWN(%x) %d bytes\n", prefix, indent, "",
 911                   value_type, value_length);
 912
 913           buffer += value_length;
 914           break;
 915     }
 916   }
 917 }
 918
 919
 920 /*
 921  * 'asn1_decode_snmp()' - Decode a SNMP packet.
 922  */
 923
 924 static int                              /* O - 0 on success, -1 on error */
 925 asn1_decode_snmp(unsigned char *buffer, /* I - Buffer */
 926                  size_t        len,     /* I - Size of buffer */
 927                  cups_snmp_t   *packet) /* I - SNMP packet */
 928 {
 929   unsigned char *bufptr,                /* Pointer into the data */
 930                 *bufend;                /* End of data */
 931   unsigned      length;                 /* Length of value */
 932
 933
 934  /*
 935   * Initialize the decoding...
 936   */
 937
 938   memset(packet, 0, sizeof(cups_snmp_t));
 939   packet->object_name[0] = -1;
 940
 941   bufptr = buffer;
 942   bufend = buffer + len;
 943
 944   if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_SEQUENCE)
 945     snmp_set_error(packet, _("Packet does not start with SEQUENCE"));
 946   else if (asn1_get_length(&bufptr, bufend) == 0)
 947     snmp_set_error(packet, _("SEQUENCE uses indefinite length"));
 948   else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
 949     snmp_set_error(packet, _("No version number"));
 950   else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
 951     snmp_set_error(packet, _("Version uses indefinite length"));
 952   else if ((packet->version = asn1_get_integer(&bufptr, bufend, length))
 953                != CUPS_SNMP_VERSION_1)
 954     snmp_set_error(packet, _("Bad SNMP version number"));
 955   else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_OCTET_STRING)
 956     snmp_set_error(packet, _("No community name"));
 957   else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
 958     snmp_set_error(packet, _("Community name uses indefinite length"));
 959   else
 960   {
 961     asn1_get_string(&bufptr, bufend, length, packet->community,
 962                     sizeof(packet->community));
 963
 964     if ((packet->request_type = (cups_asn1_t)asn1_get_type(&bufptr, bufend))
 965             != CUPS_ASN1_GET_RESPONSE)
 966       snmp_set_error(packet, _("Packet does not contain a Get-Response-PDU"));
 967     else if (asn1_get_length(&bufptr, bufend) == 0)
 968       snmp_set_error(packet, _("Get-Response-PDU uses indefinite length"));
 969     else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
 970       snmp_set_error(packet, _("No request-id"));
 971     else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
 972       snmp_set_error(packet, _("request-id uses indefinite length"));
 973     else
 974     {
 975       packet->request_id = (unsigned)asn1_get_integer(&bufptr, bufend, length);
 976
 977       if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
 978         snmp_set_error(packet, _("No error-status"));
 979       else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
 980         snmp_set_error(packet, _("error-status uses indefinite length"));
 981       else
 982       {
 983         packet->error_status = asn1_get_integer(&bufptr, bufend, length);
 984
 985         if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_INTEGER)
 986           snmp_set_error(packet, _("No error-index"));
 987         else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
 988           snmp_set_error(packet, _("error-index uses indefinite length"));
 989         else
 990         {
 991           packet->error_index = asn1_get_integer(&bufptr, bufend, length);
 992
 993           if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_SEQUENCE)
 994             snmp_set_error(packet, _("No variable-bindings SEQUENCE"));
 995           else if (asn1_get_length(&bufptr, bufend) == 0)
 996             snmp_set_error(packet,
 997                            _("variable-bindings uses indefinite length"));
 998           else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_SEQUENCE)
 999             snmp_set_error(packet, _("No VarBind SEQUENCE"));
1000           else if (asn1_get_length(&bufptr, bufend) == 0)
1001             snmp_set_error(packet, _("VarBind uses indefinite length"));
1002           else if (asn1_get_type(&bufptr, bufend) != CUPS_ASN1_OID)
1003             snmp_set_error(packet, _("No name OID"));
1004           else if ((length = asn1_get_length(&bufptr, bufend)) == 0)
1005             snmp_set_error(packet, _("Name OID uses indefinite length"));
1006           else
1007           {
1008             asn1_get_oid(&bufptr, bufend, length, packet->object_name,
1009                          CUPS_SNMP_MAX_OID);
1010
1011             packet->object_type = (cups_asn1_t)asn1_get_type(&bufptr, bufend);
1012
1013             if ((length = asn1_get_length(&bufptr, bufend)) == 0 &&
1014                 packet->object_type != CUPS_ASN1_NULL_VALUE &&
1015                 packet->object_type != CUPS_ASN1_OCTET_STRING)
1016               snmp_set_error(packet, _("Value uses indefinite length"));
1017             else
1018             {
1019               switch (packet->object_type)
1020               {
1021                 case CUPS_ASN1_BOOLEAN :
1022                     packet->object_value.boolean =
1023                         asn1_get_integer(&bufptr, bufend, length);
1024                     break;
1025
1026                 case CUPS_ASN1_INTEGER :
1027                     packet->object_value.integer =
1028                         asn1_get_integer(&bufptr, bufend, length);
1029                     break;
1030
1031                 case CUPS_ASN1_NULL_VALUE :
1032                     break;
1033
1034                 case CUPS_ASN1_OCTET_STRING :
1035                 case CUPS_ASN1_BIT_STRING :
1036                 case CUPS_ASN1_HEX_STRING :
1037                     packet->object_value.string.num_bytes = length;
1038                     asn1_get_string(&bufptr, bufend, length,
1039                                     (char *)packet->object_value.string.bytes,
1040                                     sizeof(packet->object_value.string.bytes));
1041                     break;
1042
1043                 case CUPS_ASN1_OID :
1044                     asn1_get_oid(&bufptr, bufend, length,
1045                                  packet->object_value.oid, CUPS_SNMP_MAX_OID);
1046                     break;
1047
1048                 case CUPS_ASN1_COUNTER :
1049                     packet->object_value.counter =
1050                         asn1_get_integer(&bufptr, bufend, length);
1051                     break;
1052
1053                 case CUPS_ASN1_GAUGE :
1054                     packet->object_value.gauge =
1055                         (unsigned)asn1_get_integer(&bufptr, bufend, length);
1056                     break;
1057
1058                 case CUPS_ASN1_TIMETICKS :
1059                     packet->object_value.timeticks =
1060                         (unsigned)asn1_get_integer(&bufptr, bufend, length);
1061                     break;
1062
1063                 default :
1064                     snmp_set_error(packet, _("Unsupported value type"));
1065                     break;
1066               }
1067             }
1068           }
1069         }
1070       }
1071     }
1072   }
1073
1074   return (packet->error ? -1 : 0);
1075 }
1076
1077
1078 /*
1079  * 'asn1_encode_snmp()' - Encode a SNMP packet.
1080  */
1081
1082 static int                              /* O - Length on success, -1 on error */
1083 asn1_encode_snmp(unsigned char *buffer, /* I - Buffer */
1084                  size_t        bufsize, /* I - Size of buffer */
1085                  cups_snmp_t   *packet) /* I - SNMP packet */
1086 {
1087   unsigned char *bufptr;                /* Pointer into buffer */
1088   unsigned      total,                  /* Total length */
1089                 msglen,                 /* Length of entire message */
1090                 commlen,                /* Length of community string */
1091                 reqlen,                 /* Length of request */
1092                 listlen,                /* Length of variable list */
1093                 varlen,                 /* Length of variable */
1094                 namelen,                /* Length of object name OID */
1095                 valuelen;               /* Length of object value */
1096
1097
1098  /*
1099   * Get the lengths of the community string, OID, and message...
1100   */
1101
1102
1103   namelen = asn1_size_oid(packet->object_name);
1104
1105   switch (packet->object_type)
1106   {
1107     case CUPS_ASN1_NULL_VALUE :
1108         valuelen = 0;
1109         break;
1110
1111     case CUPS_ASN1_BOOLEAN :
1112         valuelen = asn1_size_integer(packet->object_value.boolean);
1113         break;
1114
1115     case CUPS_ASN1_INTEGER :
1116         valuelen = asn1_size_integer(packet->object_value.integer);
1117         break;
1118
1119     case CUPS_ASN1_OCTET_STRING :
1120         valuelen = packet->object_value.string.num_bytes;
1121         break;
1122
1123     case CUPS_ASN1_OID :
1124         valuelen = asn1_size_oid(packet->object_value.oid);
1125         break;
1126
1127     default :
1128         packet->error = "Unknown object type";
1129         return (-1);
1130   }
1131
1132   varlen  = 1 + asn1_size_length(namelen) + namelen +
1133             1 + asn1_size_length(valuelen) + valuelen;
1134   listlen = 1 + asn1_size_length(varlen) + varlen;
1135   reqlen  = 2 + asn1_size_integer((int)packet->request_id) +
1136             2 + asn1_size_integer(packet->error_status) +
1137             2 + asn1_size_integer(packet->error_index) +
1138             1 + asn1_size_length(listlen) + listlen;
1139   commlen = (unsigned)strlen(packet->community);
1140   msglen  = 2 + asn1_size_integer(packet->version) +
1141             1 + asn1_size_length(commlen) + commlen +
1142             1 + asn1_size_length(reqlen) + reqlen;
1143   total   = 1 + asn1_size_length(msglen) + msglen;
1144
1145   if (total > bufsize)
1146   {
1147     packet->error = "Message too large for buffer";
1148     return (-1);
1149   }
1150
1151  /*
1152   * Then format the message...
1153   */
1154
1155   bufptr = buffer;
1156
1157   *bufptr++ = CUPS_ASN1_SEQUENCE;       /* SNMPv1 message header */
1158   asn1_set_length(&bufptr, msglen);
1159
1160   asn1_set_integer(&bufptr, packet->version);
1161                                         /* version */
1162
1163   *bufptr++ = CUPS_ASN1_OCTET_STRING;   /* community */
1164   asn1_set_length(&bufptr, commlen);
1165   memcpy(bufptr, packet->community, commlen);
1166   bufptr += commlen;
1167
1168   *bufptr++ = packet->request_type;     /* Get-Request-PDU/Get-Next-Request-PDU */
1169   asn1_set_length(&bufptr, reqlen);
1170
1171   asn1_set_integer(&bufptr, (int)packet->request_id);
1172
1173   asn1_set_integer(&bufptr, packet->error_status);
1174
1175   asn1_set_integer(&bufptr, packet->error_index);
1176
1177   *bufptr++ = CUPS_ASN1_SEQUENCE;       /* variable-bindings */
1178   asn1_set_length(&bufptr, listlen);
1179
1180   *bufptr++ = CUPS_ASN1_SEQUENCE;       /* variable */
1181   asn1_set_length(&bufptr, varlen);
1182
1183   asn1_set_oid(&bufptr, packet->object_name);
1184                                         /* ObjectName */
1185
1186   switch (packet->object_type)
1187   {
1188     case CUPS_ASN1_NULL_VALUE :
1189         *bufptr++ = CUPS_ASN1_NULL_VALUE;
1190                                         /* ObjectValue */
1191         *bufptr++ = 0;                  /* Length */
1192         break;
1193
1194     case CUPS_ASN1_BOOLEAN :
1195         asn1_set_integer(&bufptr, packet->object_value.boolean);
1196         break;
1197
1198     case CUPS_ASN1_INTEGER :
1199         asn1_set_integer(&bufptr, packet->object_value.integer);
1200         break;
1201
1202     case CUPS_ASN1_OCTET_STRING :
1203         *bufptr++ = CUPS_ASN1_OCTET_STRING;
1204         asn1_set_length(&bufptr, valuelen);
1205         memcpy(bufptr, packet->object_value.string.bytes, valuelen);
1206         bufptr += valuelen;
1207         break;
1208
1209     case CUPS_ASN1_OID :
1210         asn1_set_oid(&bufptr, packet->object_value.oid);
1211         break;
1212
1213     default :
1214         break;
1215   }
1216
1217   return ((int)(bufptr - buffer));
1218 }
1219
1220
1221 /*
1222  * 'asn1_get_integer()' - Get an integer value.
1223  */
1224
1225 static int                              /* O  - Integer value */
1226 asn1_get_integer(
1227     unsigned char **buffer,             /* IO - Pointer in buffer */
1228     unsigned char *bufend,              /* I  - End of buffer */
1229     unsigned      length)               /* I  - Length of value */
1230 {
1231   int   value;                          /* Integer value */
1232
1233
1234   if (length > sizeof(int))
1235   {
1236     (*buffer) += length;
1237     return (0);
1238   }
1239
1240   for (value = (**buffer & 0x80) ? -1 : 0;
1241        length > 0 && *buffer < bufend;
1242        length --, (*buffer) ++)
1243     value = (value << 8) | **buffer;
1244
1245   return (value);
1246 }
1247
1248
1249 /*
1250  * 'asn1_get_length()' - Get a value length.
1251  */
1252
1253 static unsigned                         /* O  - Length */
1254 asn1_get_length(unsigned char **buffer, /* IO - Pointer in buffer */
1255                 unsigned char *bufend)  /* I  - End of buffer */
1256 {
1257   unsigned      length;                 /* Length */
1258
1259
1260   length = **buffer;
1261   (*buffer) ++;
1262
1263   if (length & 128)
1264   {
1265     int count;                          /* Number of bytes for length */
1266
1267
1268     if ((count = length & 127) > sizeof(unsigned))
1269     {
1270       (*buffer) += count;
1271       return (0);
1272     }
1273
1274     for (length = 0;
1275          count > 0 && *buffer < bufend;
1276          count --, (*buffer) ++)
1277       length = (length << 8) | **buffer;
1278   }
1279
1280   return (length);
1281 }
1282
1283
1284 /*
1285  * 'asn1_get_oid()' - Get an OID value.
1286  */
1287
1288 static int                              /* O  - Number of OIDs */
1289 asn1_get_oid(
1290     unsigned char **buffer,             /* IO - Pointer in buffer */
1291     unsigned char *bufend,              /* I  - End of buffer */
1292     unsigned      length,               /* I  - Length of value */
1293     int           *oid,                 /* I  - OID buffer */
1294     int           oidsize)              /* I  - Size of OID buffer */
1295 {
1296   unsigned char *valend;                /* End of value */
1297   int           *oidptr,                /* Current OID */
1298                 *oidend;                /* End of OID buffer */
1299   int           number;                 /* OID number */
1300
1301
1302   valend = *buffer + length;
1303   oidptr = oid;
1304   oidend = oid + oidsize - 1;
1305
1306   if (valend > bufend)
1307     valend = bufend;
1308
1309   number = asn1_get_packed(buffer, bufend);
1310
1311   if (number < 80)
1312   {
1313     *oidptr++ = number / 40;
1314     number    = number % 40;
1315     *oidptr++ = number;
1316   }
1317   else
1318   {
1319     *oidptr++ = 2;
1320     number    -= 80;
1321     *oidptr++ = number;
1322   }
1323
1324   while (*buffer < valend)
1325   {
1326     number = asn1_get_packed(buffer, bufend);
1327
1328     if (oidptr < oidend)
1329       *oidptr++ = number;
1330   }
1331
1332   *oidptr = -1;
1333
1334   return ((int)(oidptr - oid));
1335 }
1336
1337
1338 /*
1339  * 'asn1_get_packed()' - Get a packed integer value.
1340  */
1341
1342 static int                              /* O  - Value */
1343 asn1_get_packed(
1344     unsigned char **buffer,             /* IO - Pointer in buffer */
1345     unsigned char *bufend)              /* I  - End of buffer */
1346 {
1347   int   value;                          /* Value */
1348
1349
1350   value = 0;
1351
1352   while ((**buffer & 128) && *buffer < bufend)
1353   {
1354     value = (value << 7) | (**buffer & 127);
1355     (*buffer) ++;
1356   }
1357
1358   if (*buffer < bufend)
1359   {
1360     value = (value << 7) | **buffer;
1361     (*buffer) ++;
1362   }
1363
1364   return (value);
1365 }
1366
1367
1368 /*
1369  * 'asn1_get_string()' - Get a string value.
1370  */
1371
1372 static char *                           /* O  - String */
1373 asn1_get_string(
1374     unsigned char **buffer,             /* IO - Pointer in buffer */
1375     unsigned char *bufend,              /* I  - End of buffer */
1376     unsigned      length,               /* I  - Value length */
1377     char          *string,              /* I  - String buffer */
1378     size_t        strsize)              /* I  - String buffer size */
1379 {
1380   if (length > (unsigned)(bufend - *buffer))
1381     length = (unsigned)(bufend - *buffer);
1382
1383   if (length < strsize)
1384   {
1385    /*
1386     * String is smaller than the buffer...
1387     */
1388
1389     if (length > 0)
1390       memcpy(string, *buffer, length);
1391
1392     string[length] = '\0';
1393   }
1394   else
1395   {
1396    /*
1397     * String is larger than the buffer...
1398     */
1399
1400     memcpy(string, *buffer, strsize - 1);
1401     string[strsize - 1] = '\0';
1402   }
1403
1404   if (length > 0)
1405     (*buffer) += length;
1406
1407   return (string);
1408 }
1409
1410
1411 /*
1412  * 'asn1_get_type()' - Get a value type.
1413  */
1414
1415 static int                              /* O  - Type */
1416 asn1_get_type(unsigned char **buffer,   /* IO - Pointer in buffer */
1417               unsigned char *bufend)    /* I  - End of buffer */
1418 {
1419   int   type;                           /* Type */
1420
1421
1422   type = **buffer;
1423   (*buffer) ++;
1424
1425   if ((type & 31) == 31)
1426     type = asn1_get_packed(buffer, bufend);
1427
1428   return (type);
1429 }
1430
1431
1432 /*
1433  * 'asn1_set_integer()' - Set an integer value.
1434  */
1435
1436 static void
1437 asn1_set_integer(unsigned char **buffer,/* IO - Pointer in buffer */
1438                  int           integer) /* I  - Integer value */
1439 {
1440   **buffer = CUPS_ASN1_INTEGER;
1441   (*buffer) ++;
1442
1443   if (integer > 0x7fffff || integer < -0x800000)
1444   {
1445     **buffer = 4;
1446     (*buffer) ++;
1447     **buffer = (unsigned char)(integer >> 24);
1448     (*buffer) ++;
1449     **buffer = (unsigned char)(integer >> 16);
1450     (*buffer) ++;
1451     **buffer = (unsigned char)(integer >> 8);
1452     (*buffer) ++;
1453     **buffer = (unsigned char)integer;
1454     (*buffer) ++;
1455   }
1456   else if (integer > 0x7fff || integer < -0x8000)
1457   {
1458     **buffer = 3;
1459     (*buffer) ++;
1460     **buffer = (unsigned char)(integer >> 16);
1461     (*buffer) ++;
1462     **buffer = (unsigned char)(integer >> 8);
1463     (*buffer) ++;
1464     **buffer = (unsigned char)integer;
1465     (*buffer) ++;
1466   }
1467   else if (integer > 0x7f || integer < -0x80)
1468   {
1469     **buffer = 2;
1470     (*buffer) ++;
1471     **buffer = (unsigned char)(integer >> 8);
1472     (*buffer) ++;
1473     **buffer = (unsigned char)integer;
1474     (*buffer) ++;
1475   }
1476   else
1477   {
1478     **buffer = 1;
1479     (*buffer) ++;
1480     **buffer = (unsigned char)integer;
1481     (*buffer) ++;
1482   }
1483 }
1484
1485
1486 /*
1487  * 'asn1_set_length()' - Set a value length.
1488  */
1489
1490 static void
1491 asn1_set_length(unsigned char **buffer, /* IO - Pointer in buffer */
1492                 unsigned      length)   /* I  - Length value */
1493 {
1494   if (length > 255)
1495   {
1496     **buffer = 0x82;                    /* 2-byte length */
1497     (*buffer) ++;
1498     **buffer = (unsigned char)(length >> 8);
1499     (*buffer) ++;
1500     **buffer = (unsigned char)length;
1501     (*buffer) ++;
1502   }
1503   else if (length > 127)
1504   {
1505     **buffer = 0x81;                    /* 1-byte length */
1506     (*buffer) ++;
1507     **buffer = (unsigned char)length;
1508     (*buffer) ++;
1509   }
1510   else
1511   {
1512     **buffer = (unsigned char)length;   /* Length */
1513     (*buffer) ++;
1514   }
1515 }
1516
1517
1518 /*
1519  * 'asn1_set_oid()' - Set an OID value.
1520  */
1521
1522 static void
1523 asn1_set_oid(unsigned char **buffer,    /* IO - Pointer in buffer */
1524              const int     *oid)        /* I  - OID value */
1525 {
1526   **buffer = CUPS_ASN1_OID;
1527   (*buffer) ++;
1528
1529   asn1_set_length(buffer, asn1_size_oid(oid));
1530
1531   if (oid[1] < 0)
1532   {
1533     asn1_set_packed(buffer, oid[0] * 40);
1534     return;
1535   }
1536
1537   asn1_set_packed(buffer, oid[0] * 40 + oid[1]);
1538
1539   for (oid += 2; *oid >= 0; oid ++)
1540     asn1_set_packed(buffer, *oid);
1541 }
1542
1543
1544 /*
1545  * 'asn1_set_packed()' - Set a packed integer value.
1546  */
1547
1548 static void
1549 asn1_set_packed(unsigned char **buffer, /* IO - Pointer in buffer */
1550                 int           integer)  /* I  - Integer value */
1551 {
1552   if (integer > 0xfffffff)
1553   {
1554     **buffer = ((integer >> 28) & 0x7f) | 0x80;
1555     (*buffer) ++;
1556   }
1557
1558   if (integer > 0x1fffff)
1559   {
1560     **buffer = ((integer >> 21) & 0x7f) | 0x80;
1561     (*buffer) ++;
1562   }
1563
1564   if (integer > 0x3fff)
1565   {
1566     **buffer = ((integer >> 14) & 0x7f) | 0x80;
1567     (*buffer) ++;
1568   }
1569
1570   if (integer > 0x7f)
1571   {
1572     **buffer = ((integer >> 7) & 0x7f) | 0x80;
1573     (*buffer) ++;
1574   }
1575
1576   **buffer = integer & 0x7f;
1577   (*buffer) ++;
1578 }
1579
1580
1581 /*
1582  * 'asn1_size_integer()' - Figure out the number of bytes needed for an
1583  *                         integer value.
1584  */
1585
1586 static unsigned                         /* O - Size in bytes */
1587 asn1_size_integer(int integer)          /* I - Integer value */
1588 {
1589   if (integer > 0x7fffff || integer < -0x800000)
1590     return (4);
1591   else if (integer > 0x7fff || integer < -0x8000)
1592     return (3);
1593   else if (integer > 0x7f || integer < -0x80)
1594     return (2);
1595   else
1596     return (1);
1597 }
1598
1599
1600 /*
1601  * 'asn1_size_length()' - Figure out the number of bytes needed for a
1602  *                        length value.
1603  */
1604
1605 static unsigned                         /* O - Size in bytes */
1606 asn1_size_length(unsigned length)       /* I - Length value */
1607 {
1608   if (length > 0xff)
1609     return (3);
1610   else if (length > 0x7f)
1611     return (2);
1612   else
1613     return (1);
1614 }
1615
1616
1617 /*
1618  * 'asn1_size_oid()' - Figure out the numebr of bytes needed for an
1619  *                     OID value.
1620  */
1621
1622 static unsigned                         /* O - Size in bytes */
1623 asn1_size_oid(const int *oid)           /* I - OID value */
1624 {
1625   unsigned      length;                 /* Length of value */
1626
1627
1628   if (oid[1] < 0)
1629     return (asn1_size_packed(oid[0] * 40));
1630
1631   for (length = asn1_size_packed(oid[0] * 40 + oid[1]), oid += 2;
1632        *oid >= 0;
1633        oid ++)
1634     length += asn1_size_packed(*oid);
1635
1636   return (length);
1637 }
1638
1639
1640 /*
1641  * 'asn1_size_packed()' - Figure out the number of bytes needed for a
1642  *                        packed integer value.
1643  */
1644
1645 static unsigned                         /* O - Size in bytes */
1646 asn1_size_packed(int integer)           /* I - Integer value */
1647 {
1648   if (integer > 0xfffffff)
1649     return (5);
1650   else if (integer > 0x1fffff)
1651     return (4);
1652   else if (integer > 0x3fff)
1653     return (3);
1654   else if (integer > 0x7f)
1655     return (2);
1656   else
1657     return (1);
1658 }
1659
1660
1661 /*
1662  * 'snmp_set_error()' - Set the localized error for a packet.
1663  */
1664
1665 static void
1666 snmp_set_error(cups_snmp_t *packet,     /* I - Packet */
1667                const char *message)     /* I - Error message */
1668 {
1669   _cups_globals_t *cg = _cupsGlobals(); /* Global data */
1670
1671
1672   if (!cg->lang_default)
1673     cg->lang_default = cupsLangDefault();
1674
1675   packet->error = _cupsLangString(cg->lang_default, message);
1676 }