1 /* 2 * Copyright (c) 2001-2003 3 * Fraunhofer Institute for Open Communication Systems (FhG Fokus). 4 * All rights reserved. 5 * 6 * Author: Harti Brandt <harti@freebsd.org> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $Begemot: bsnmp/lib/snmp.c,v 1.40 2005/10/04 14:32:42 brandt_h Exp $ 30 * 31 * SNMP 32 */ 33 #include <sys/types.h> 34 #include <sys/socket.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <stddef.h> 38 #include <stdarg.h> 39 #ifdef HAVE_STDINT_H 40 #include <stdint.h> 41 #elif defined(HAVE_INTTYPES_H) 42 #include <inttypes.h> 43 #endif 44 #include <string.h> 45 #include <ctype.h> 46 #include <netdb.h> 47 #include <errno.h> 48 49 #include "asn1.h" 50 #include "snmp.h" 51 #include "snmppriv.h" 52 53 static void snmp_error_func(const char *, ...); 54 static void snmp_printf_func(const char *, ...); 55 56 void (*snmp_error)(const char *, ...) = snmp_error_func; 57 void (*snmp_printf)(const char *, ...) = snmp_printf_func; 58 59 /* 60 * Get the next variable binding from the list. 61 * ASN errors on the sequence or the OID are always fatal. 62 */ 63 static enum asn_err 64 get_var_binding(struct asn_buf *b, struct snmp_value *binding) 65 { 66 u_char type; 67 asn_len_t len, trailer; 68 enum asn_err err; 69 70 if (asn_get_sequence(b, &len) != ASN_ERR_OK) { 71 snmp_error("cannot parse varbind header"); 72 return (ASN_ERR_FAILED); 73 } 74 75 /* temporary truncate the length so that the parser does not 76 * eat up bytes behind the sequence in the case the encoding is 77 * wrong of inner elements. */ 78 trailer = b->asn_len - len; 79 b->asn_len = len; 80 81 if (asn_get_objid(b, &binding->var) != ASN_ERR_OK) { 82 snmp_error("cannot parse binding objid"); 83 return (ASN_ERR_FAILED); 84 } 85 if (asn_get_header(b, &type, &len) != ASN_ERR_OK) { 86 snmp_error("cannot parse binding value header"); 87 return (ASN_ERR_FAILED); 88 } 89 90 switch (type) { 91 92 case ASN_TYPE_NULL: 93 binding->syntax = SNMP_SYNTAX_NULL; 94 err = asn_get_null_raw(b, len); 95 break; 96 97 case ASN_TYPE_INTEGER: 98 binding->syntax = SNMP_SYNTAX_INTEGER; 99 err = asn_get_integer_raw(b, len, &binding->v.integer); 100 break; 101 102 case ASN_TYPE_OCTETSTRING: 103 binding->syntax = SNMP_SYNTAX_OCTETSTRING; 104 binding->v.octetstring.octets = malloc(len); 105 if (binding->v.octetstring.octets == NULL) { 106 snmp_error("%s", strerror(errno)); 107 return (ASN_ERR_FAILED); 108 } 109 binding->v.octetstring.len = len; 110 err = asn_get_octetstring_raw(b, len, 111 binding->v.octetstring.octets, 112 &binding->v.octetstring.len); 113 if (ASN_ERR_STOPPED(err)) { 114 free(binding->v.octetstring.octets); 115 binding->v.octetstring.octets = NULL; 116 } 117 break; 118 119 case ASN_TYPE_OBJID: 120 binding->syntax = SNMP_SYNTAX_OID; 121 err = asn_get_objid_raw(b, len, &binding->v.oid); 122 break; 123 124 case ASN_CLASS_APPLICATION|ASN_APP_IPADDRESS: 125 binding->syntax = SNMP_SYNTAX_IPADDRESS; 126 err = asn_get_ipaddress_raw(b, len, binding->v.ipaddress); 127 break; 128 129 case ASN_CLASS_APPLICATION|ASN_APP_TIMETICKS: 130 binding->syntax = SNMP_SYNTAX_TIMETICKS; 131 err = asn_get_uint32_raw(b, len, &binding->v.uint32); 132 break; 133 134 case ASN_CLASS_APPLICATION|ASN_APP_COUNTER: 135 binding->syntax = SNMP_SYNTAX_COUNTER; 136 err = asn_get_uint32_raw(b, len, &binding->v.uint32); 137 break; 138 139 case ASN_CLASS_APPLICATION|ASN_APP_GAUGE: 140 binding->syntax = SNMP_SYNTAX_GAUGE; 141 err = asn_get_uint32_raw(b, len, &binding->v.uint32); 142 break; 143 144 case ASN_CLASS_APPLICATION|ASN_APP_COUNTER64: 145 binding->syntax = SNMP_SYNTAX_COUNTER64; 146 err = asn_get_counter64_raw(b, len, &binding->v.counter64); 147 break; 148 149 case ASN_CLASS_CONTEXT | ASN_EXCEPT_NOSUCHOBJECT: 150 binding->syntax = SNMP_SYNTAX_NOSUCHOBJECT; 151 err = asn_get_null_raw(b, len); 152 break; 153 154 case ASN_CLASS_CONTEXT | ASN_EXCEPT_NOSUCHINSTANCE: 155 binding->syntax = SNMP_SYNTAX_NOSUCHINSTANCE; 156 err = asn_get_null_raw(b, len); 157 break; 158 159 case ASN_CLASS_CONTEXT | ASN_EXCEPT_ENDOFMIBVIEW: 160 binding->syntax = SNMP_SYNTAX_ENDOFMIBVIEW; 161 err = asn_get_null_raw(b, len); 162 break; 163 164 default: 165 if ((err = asn_skip(b, len)) == ASN_ERR_OK) 166 err = ASN_ERR_TAG; 167 snmp_error("bad binding value type 0x%x", type); 168 break; 169 } 170 171 if (ASN_ERR_STOPPED(err)) { 172 snmp_error("cannot parse binding value"); 173 return (err); 174 } 175 176 if (b->asn_len != 0) 177 snmp_error("ignoring junk at end of binding"); 178 179 b->asn_len = trailer; 180 181 return (err); 182 } 183 184 /* 185 * Parse the different PDUs contents. Any ASN error in the outer components 186 * are fatal. Only errors in variable values may be tolerated. If all 187 * components can be parsed it returns either ASN_ERR_OK or the first 188 * error that was found. 189 */ 190 enum asn_err 191 snmp_parse_pdus_hdr(struct asn_buf *b, struct snmp_pdu *pdu, asn_len_t *lenp) 192 { 193 if (pdu->type == SNMP_PDU_TRAP) { 194 if (asn_get_objid(b, &pdu->enterprise) != ASN_ERR_OK) { 195 snmp_error("cannot parse trap enterprise"); 196 return (ASN_ERR_FAILED); 197 } 198 if (asn_get_ipaddress(b, pdu->agent_addr) != ASN_ERR_OK) { 199 snmp_error("cannot parse trap agent address"); 200 return (ASN_ERR_FAILED); 201 } 202 if (asn_get_integer(b, &pdu->generic_trap) != ASN_ERR_OK) { 203 snmp_error("cannot parse 'generic-trap'"); 204 return (ASN_ERR_FAILED); 205 } 206 if (asn_get_integer(b, &pdu->specific_trap) != ASN_ERR_OK) { 207 snmp_error("cannot parse 'specific-trap'"); 208 return (ASN_ERR_FAILED); 209 } 210 if (asn_get_timeticks(b, &pdu->time_stamp) != ASN_ERR_OK) { 211 snmp_error("cannot parse trap 'time-stamp'"); 212 return (ASN_ERR_FAILED); 213 } 214 } else { 215 if (asn_get_integer(b, &pdu->request_id) != ASN_ERR_OK) { 216 snmp_error("cannot parse 'request-id'"); 217 return (ASN_ERR_FAILED); 218 } 219 if (asn_get_integer(b, &pdu->error_status) != ASN_ERR_OK) { 220 snmp_error("cannot parse 'error_status'"); 221 return (ASN_ERR_FAILED); 222 } 223 if (asn_get_integer(b, &pdu->error_index) != ASN_ERR_OK) { 224 snmp_error("cannot parse 'error_index'"); 225 return (ASN_ERR_FAILED); 226 } 227 } 228 229 if (asn_get_sequence(b, lenp) != ASN_ERR_OK) { 230 snmp_error("cannot get varlist header"); 231 return (ASN_ERR_FAILED); 232 } 233 234 return (ASN_ERR_OK); 235 } 236 237 static enum asn_err 238 parse_pdus(struct asn_buf *b, struct snmp_pdu *pdu, int32_t *ip) 239 { 240 asn_len_t len, trailer; 241 struct snmp_value *v; 242 enum asn_err err, err1; 243 244 err = snmp_parse_pdus_hdr(b, pdu, &len); 245 if (ASN_ERR_STOPPED(err)) 246 return (err); 247 248 trailer = b->asn_len - len; 249 250 v = pdu->bindings; 251 err = ASN_ERR_OK; 252 while (b->asn_len != 0) { 253 if (pdu->nbindings == SNMP_MAX_BINDINGS) { 254 snmp_error("too many bindings (> %u) in PDU", 255 SNMP_MAX_BINDINGS); 256 return (ASN_ERR_FAILED); 257 } 258 err1 = get_var_binding(b, v); 259 if (ASN_ERR_STOPPED(err1)) 260 return (ASN_ERR_FAILED); 261 if (err1 != ASN_ERR_OK && err == ASN_ERR_OK) { 262 err = err1; 263 *ip = pdu->nbindings + 1; 264 } 265 pdu->nbindings++; 266 v++; 267 } 268 269 b->asn_len = trailer; 270 271 return (err); 272 } 273 274 /* 275 * Parse the outer SEQUENCE value. ASN_ERR_TAG means 'bad version'. 276 */ 277 enum asn_err 278 snmp_parse_message_hdr(struct asn_buf *b, struct snmp_pdu *pdu, asn_len_t *lenp) 279 { 280 int32_t version; 281 u_char type; 282 u_int comm_len; 283 284 if (asn_get_integer(b, &version) != ASN_ERR_OK) { 285 snmp_error("cannot decode version"); 286 return (ASN_ERR_FAILED); 287 } 288 289 if (version == 0) { 290 pdu->version = SNMP_V1; 291 } else if (version == 1) { 292 pdu->version = SNMP_V2c; 293 } else { 294 pdu->version = SNMP_Verr; 295 snmp_error("unsupported SNMP version"); 296 return (ASN_ERR_TAG); 297 } 298 299 comm_len = SNMP_COMMUNITY_MAXLEN; 300 if (asn_get_octetstring(b, (u_char *)pdu->community, 301 &comm_len) != ASN_ERR_OK) { 302 snmp_error("cannot decode community"); 303 return (ASN_ERR_FAILED); 304 } 305 pdu->community[comm_len] = '\0'; 306 307 if (asn_get_header(b, &type, lenp) != ASN_ERR_OK) { 308 snmp_error("cannot get pdu header"); 309 return (ASN_ERR_FAILED); 310 } 311 if ((type & ~ASN_TYPE_MASK) != 312 (ASN_TYPE_CONSTRUCTED | ASN_CLASS_CONTEXT)) { 313 snmp_error("bad pdu header tag"); 314 return (ASN_ERR_FAILED); 315 } 316 pdu->type = type & ASN_TYPE_MASK; 317 318 switch (pdu->type) { 319 320 case SNMP_PDU_GET: 321 case SNMP_PDU_GETNEXT: 322 case SNMP_PDU_RESPONSE: 323 case SNMP_PDU_SET: 324 break; 325 326 case SNMP_PDU_TRAP: 327 if (pdu->version != SNMP_V1) { 328 snmp_error("bad pdu type %u", pdu->type); 329 return (ASN_ERR_FAILED); 330 } 331 break; 332 333 case SNMP_PDU_GETBULK: 334 case SNMP_PDU_INFORM: 335 case SNMP_PDU_TRAP2: 336 case SNMP_PDU_REPORT: 337 if (pdu->version == SNMP_V1) { 338 snmp_error("bad pdu type %u", pdu->type); 339 return (ASN_ERR_FAILED); 340 } 341 break; 342 343 default: 344 snmp_error("bad pdu type %u", pdu->type); 345 return (ASN_ERR_FAILED); 346 } 347 348 349 if (*lenp > b->asn_len) { 350 snmp_error("pdu length too long"); 351 return (ASN_ERR_FAILED); 352 } 353 354 return (ASN_ERR_OK); 355 } 356 357 static enum asn_err 358 parse_message(struct asn_buf *b, struct snmp_pdu *pdu, int32_t *ip) 359 { 360 enum asn_err err; 361 asn_len_t len, trailer; 362 363 err = snmp_parse_message_hdr(b, pdu, &len); 364 if (ASN_ERR_STOPPED(err)) 365 return (err); 366 367 trailer = b->asn_len - len; 368 b->asn_len = len; 369 370 err = parse_pdus(b, pdu, ip); 371 if (ASN_ERR_STOPPED(err)) 372 return (ASN_ERR_FAILED); 373 374 if (b->asn_len != 0) 375 snmp_error("ignoring trailing junk after pdu"); 376 377 b->asn_len = trailer; 378 379 return (err); 380 } 381 382 /* 383 * Decode the PDU except for the variable bindings itself. 384 * If decoding fails because of a bad binding, but the rest can be 385 * decoded, ip points to the index of the failed variable (errors 386 * OORANGE, BADLEN or BADVERS). 387 */ 388 enum snmp_code 389 snmp_pdu_decode(struct asn_buf *b, struct snmp_pdu *pdu, int32_t *ip) 390 { 391 asn_len_t len; 392 393 memset(pdu, 0, sizeof(*pdu)); 394 395 if (asn_get_sequence(b, &len) != ASN_ERR_OK) { 396 snmp_error("cannot decode pdu header"); 397 return (SNMP_CODE_FAILED); 398 } 399 if (b->asn_len < len) { 400 snmp_error("outer sequence value too short"); 401 return (SNMP_CODE_FAILED); 402 } 403 if (b->asn_len != len) { 404 snmp_error("ignoring trailing junk in message"); 405 b->asn_len = len; 406 } 407 408 switch (parse_message(b, pdu, ip)) { 409 410 case ASN_ERR_OK: 411 return (SNMP_CODE_OK); 412 413 case ASN_ERR_FAILED: 414 case ASN_ERR_EOBUF: 415 snmp_pdu_free(pdu); 416 return (SNMP_CODE_FAILED); 417 418 case ASN_ERR_BADLEN: 419 return (SNMP_CODE_BADLEN); 420 421 case ASN_ERR_RANGE: 422 return (SNMP_CODE_OORANGE); 423 424 case ASN_ERR_TAG: 425 if (pdu->version == SNMP_Verr) 426 return (SNMP_CODE_BADVERS); 427 else 428 return (SNMP_CODE_BADENC); 429 } 430 431 return (SNMP_CODE_OK); 432 } 433 434 /* 435 * Check whether what we have is the complete PDU by snooping at the 436 * enclosing structure header. This returns: 437 * -1 if there are ASN.1 errors 438 * 0 if we need more data 439 * > 0 the length of this PDU 440 */ 441 int 442 snmp_pdu_snoop(const struct asn_buf *b0) 443 { 444 u_int length; 445 asn_len_t len; 446 struct asn_buf b = *b0; 447 448 /* <0x10|0x20> <len> <data...> */ 449 450 if (b.asn_len == 0) 451 return (0); 452 if (b.asn_cptr[0] != (ASN_TYPE_SEQUENCE | ASN_TYPE_CONSTRUCTED)) { 453 asn_error(&b, "bad sequence type %u", b.asn_cptr[0]); 454 return (-1); 455 } 456 b.asn_len--; 457 b.asn_cptr++; 458 459 if (b.asn_len == 0) 460 return (0); 461 462 if (*b.asn_cptr & 0x80) { 463 /* long length */ 464 length = *b.asn_cptr++ & 0x7f; 465 b.asn_len--; 466 if (length == 0) { 467 asn_error(&b, "indefinite length not supported"); 468 return (-1); 469 } 470 if (length > ASN_MAXLENLEN) { 471 asn_error(&b, "long length too long (%u)", length); 472 return (-1); 473 } 474 if (length > b.asn_len) 475 return (0); 476 len = 0; 477 while (length--) { 478 len = (len << 8) | *b.asn_cptr++; 479 b.asn_len--; 480 } 481 } else { 482 len = *b.asn_cptr++; 483 b.asn_len--; 484 } 485 486 if (len > b.asn_len) 487 return (0); 488 489 return (len + b.asn_cptr - b0->asn_cptr); 490 } 491 492 /* 493 * Encode the SNMP PDU without the variable bindings field. 494 * We do this the rather uneffective way by 495 * moving things around and assuming that the length field will never 496 * use more than 2 bytes. 497 * We need a number of pointers to apply the fixes afterwards. 498 */ 499 enum snmp_code 500 snmp_pdu_encode_header(struct asn_buf *b, struct snmp_pdu *pdu) 501 { 502 enum asn_err err; 503 504 if (asn_put_temp_header(b, (ASN_TYPE_SEQUENCE|ASN_TYPE_CONSTRUCTED), 505 &pdu->outer_ptr) != ASN_ERR_OK) 506 return (SNMP_CODE_FAILED); 507 508 if (pdu->version == SNMP_V1) 509 err = asn_put_integer(b, 0); 510 else if (pdu->version == SNMP_V2c) 511 err = asn_put_integer(b, 1); 512 else 513 return (SNMP_CODE_BADVERS); 514 if (err != ASN_ERR_OK) 515 return (SNMP_CODE_FAILED); 516 517 if (asn_put_octetstring(b, (u_char *)pdu->community, 518 strlen(pdu->community)) != ASN_ERR_OK) 519 return (SNMP_CODE_FAILED); 520 521 if (asn_put_temp_header(b, (ASN_TYPE_CONSTRUCTED | ASN_CLASS_CONTEXT | 522 pdu->type), &pdu->pdu_ptr) != ASN_ERR_OK) 523 return (SNMP_CODE_FAILED); 524 525 if (pdu->type == SNMP_PDU_TRAP) { 526 if (pdu->version != SNMP_V1 || 527 asn_put_objid(b, &pdu->enterprise) != ASN_ERR_OK || 528 asn_put_ipaddress(b, pdu->agent_addr) != ASN_ERR_OK || 529 asn_put_integer(b, pdu->generic_trap) != ASN_ERR_OK || 530 asn_put_integer(b, pdu->specific_trap) != ASN_ERR_OK || 531 asn_put_timeticks(b, pdu->time_stamp) != ASN_ERR_OK) 532 return (SNMP_CODE_FAILED); 533 } else { 534 if (pdu->version == SNMP_V1 && (pdu->type == SNMP_PDU_GETBULK || 535 pdu->type == SNMP_PDU_INFORM || 536 pdu->type == SNMP_PDU_TRAP2 || 537 pdu->type == SNMP_PDU_REPORT)) 538 return (SNMP_CODE_FAILED); 539 540 if (asn_put_integer(b, pdu->request_id) != ASN_ERR_OK || 541 asn_put_integer(b, pdu->error_status) != ASN_ERR_OK || 542 asn_put_integer(b, pdu->error_index) != ASN_ERR_OK) 543 return (SNMP_CODE_FAILED); 544 } 545 546 if (asn_put_temp_header(b, (ASN_TYPE_SEQUENCE|ASN_TYPE_CONSTRUCTED), 547 &pdu->vars_ptr) != ASN_ERR_OK) 548 return (SNMP_CODE_FAILED); 549 550 return (SNMP_CODE_OK); 551 } 552 553 enum snmp_code 554 snmp_fix_encoding(struct asn_buf *b, const struct snmp_pdu *pdu) 555 { 556 if (asn_commit_header(b, pdu->vars_ptr) != ASN_ERR_OK || 557 asn_commit_header(b, pdu->pdu_ptr) != ASN_ERR_OK || 558 asn_commit_header(b, pdu->outer_ptr) != ASN_ERR_OK) 559 return (SNMP_CODE_FAILED); 560 return (SNMP_CODE_OK); 561 } 562 563 /* 564 * Encode a binding. Caller must ensure, that the syntax is ok for that version. 565 * Be sure not to cobber b, when something fails. 566 */ 567 enum asn_err 568 snmp_binding_encode(struct asn_buf *b, const struct snmp_value *binding) 569 { 570 u_char *ptr; 571 enum asn_err err; 572 struct asn_buf save = *b; 573 574 if ((err = asn_put_temp_header(b, (ASN_TYPE_SEQUENCE | 575 ASN_TYPE_CONSTRUCTED), &ptr)) != ASN_ERR_OK) { 576 *b = save; 577 return (err); 578 } 579 580 if ((err = asn_put_objid(b, &binding->var)) != ASN_ERR_OK) { 581 *b = save; 582 return (err); 583 } 584 585 switch (binding->syntax) { 586 587 case SNMP_SYNTAX_NULL: 588 err = asn_put_null(b); 589 break; 590 591 case SNMP_SYNTAX_INTEGER: 592 err = asn_put_integer(b, binding->v.integer); 593 break; 594 595 case SNMP_SYNTAX_OCTETSTRING: 596 err = asn_put_octetstring(b, binding->v.octetstring.octets, 597 binding->v.octetstring.len); 598 break; 599 600 case SNMP_SYNTAX_OID: 601 err = asn_put_objid(b, &binding->v.oid); 602 break; 603 604 case SNMP_SYNTAX_IPADDRESS: 605 err = asn_put_ipaddress(b, binding->v.ipaddress); 606 break; 607 608 case SNMP_SYNTAX_TIMETICKS: 609 err = asn_put_uint32(b, ASN_APP_TIMETICKS, binding->v.uint32); 610 break; 611 612 case SNMP_SYNTAX_COUNTER: 613 err = asn_put_uint32(b, ASN_APP_COUNTER, binding->v.uint32); 614 break; 615 616 case SNMP_SYNTAX_GAUGE: 617 err = asn_put_uint32(b, ASN_APP_GAUGE, binding->v.uint32); 618 break; 619 620 case SNMP_SYNTAX_COUNTER64: 621 err = asn_put_counter64(b, binding->v.counter64); 622 break; 623 624 case SNMP_SYNTAX_NOSUCHOBJECT: 625 err = asn_put_exception(b, ASN_EXCEPT_NOSUCHOBJECT); 626 break; 627 628 case SNMP_SYNTAX_NOSUCHINSTANCE: 629 err = asn_put_exception(b, ASN_EXCEPT_NOSUCHINSTANCE); 630 break; 631 632 case SNMP_SYNTAX_ENDOFMIBVIEW: 633 err = asn_put_exception(b, ASN_EXCEPT_ENDOFMIBVIEW); 634 break; 635 } 636 637 if (err != ASN_ERR_OK) { 638 *b = save; 639 return (err); 640 } 641 642 err = asn_commit_header(b, ptr); 643 if (err != ASN_ERR_OK) { 644 *b = save; 645 return (err); 646 } 647 648 return (ASN_ERR_OK); 649 } 650 651 /* 652 * Encode an PDU. 653 */ 654 enum snmp_code 655 snmp_pdu_encode(struct snmp_pdu *pdu, struct asn_buf *resp_b) 656 { 657 u_int idx; 658 enum snmp_code err; 659 660 if ((err = snmp_pdu_encode_header(resp_b, pdu)) != SNMP_CODE_OK) 661 return (err); 662 for (idx = 0; idx < pdu->nbindings; idx++) 663 if ((err = snmp_binding_encode(resp_b, &pdu->bindings[idx])) 664 != ASN_ERR_OK) 665 return (SNMP_CODE_FAILED); 666 667 return (snmp_fix_encoding(resp_b, pdu)); 668 } 669 670 static void 671 dump_binding(const struct snmp_value *b) 672 { 673 u_int i; 674 char buf[ASN_OIDSTRLEN]; 675 676 snmp_printf("%s=", asn_oid2str_r(&b->var, buf)); 677 switch (b->syntax) { 678 679 case SNMP_SYNTAX_NULL: 680 snmp_printf("NULL"); 681 break; 682 683 case SNMP_SYNTAX_INTEGER: 684 snmp_printf("INTEGER %d", b->v.integer); 685 break; 686 687 case SNMP_SYNTAX_OCTETSTRING: 688 snmp_printf("OCTET STRING %lu:", b->v.octetstring.len); 689 for (i = 0; i < b->v.octetstring.len; i++) 690 snmp_printf(" %02x", b->v.octetstring.octets[i]); 691 break; 692 693 case SNMP_SYNTAX_OID: 694 snmp_printf("OID %s", asn_oid2str_r(&b->v.oid, buf)); 695 break; 696 697 case SNMP_SYNTAX_IPADDRESS: 698 snmp_printf("IPADDRESS %u.%u.%u.%u", b->v.ipaddress[0], 699 b->v.ipaddress[1], b->v.ipaddress[2], b->v.ipaddress[3]); 700 break; 701 702 case SNMP_SYNTAX_COUNTER: 703 snmp_printf("COUNTER %u", b->v.uint32); 704 break; 705 706 case SNMP_SYNTAX_GAUGE: 707 snmp_printf("GAUGE %u", b->v.uint32); 708 break; 709 710 case SNMP_SYNTAX_TIMETICKS: 711 snmp_printf("TIMETICKS %u", b->v.uint32); 712 break; 713 714 case SNMP_SYNTAX_COUNTER64: 715 snmp_printf("COUNTER64 %lld", b->v.counter64); 716 break; 717 718 case SNMP_SYNTAX_NOSUCHOBJECT: 719 snmp_printf("NoSuchObject"); 720 break; 721 722 case SNMP_SYNTAX_NOSUCHINSTANCE: 723 snmp_printf("NoSuchInstance"); 724 break; 725 726 case SNMP_SYNTAX_ENDOFMIBVIEW: 727 snmp_printf("EndOfMibView"); 728 break; 729 730 default: 731 snmp_printf("UNKNOWN SYNTAX %u", b->syntax); 732 break; 733 } 734 } 735 736 static __inline void 737 dump_bindings(const struct snmp_pdu *pdu) 738 { 739 u_int i; 740 741 for (i = 0; i < pdu->nbindings; i++) { 742 snmp_printf(" [%u]: ", i); 743 dump_binding(&pdu->bindings[i]); 744 snmp_printf("\n"); 745 } 746 } 747 748 static __inline void 749 dump_notrap(const struct snmp_pdu *pdu) 750 { 751 snmp_printf(" request_id=%d", pdu->request_id); 752 snmp_printf(" error_status=%d", pdu->error_status); 753 snmp_printf(" error_index=%d\n", pdu->error_index); 754 dump_bindings(pdu); 755 } 756 757 void 758 snmp_pdu_dump(const struct snmp_pdu *pdu) 759 { 760 char buf[ASN_OIDSTRLEN]; 761 const char *vers; 762 static const char *types[] = { 763 [SNMP_PDU_GET] = "GET", 764 [SNMP_PDU_GETNEXT] = "GETNEXT", 765 [SNMP_PDU_RESPONSE] = "RESPONSE", 766 [SNMP_PDU_SET] = "SET", 767 [SNMP_PDU_TRAP] = "TRAPv1", 768 [SNMP_PDU_GETBULK] = "GETBULK", 769 [SNMP_PDU_INFORM] = "INFORM", 770 [SNMP_PDU_TRAP2] = "TRAPv2", 771 [SNMP_PDU_REPORT] = "REPORT", 772 }; 773 774 if (pdu->version == SNMP_V1) 775 vers = "SNMPv1"; 776 else if (pdu->version == SNMP_V2c) 777 vers = "SNMPv2c"; 778 else 779 vers = "v?"; 780 781 switch (pdu->type) { 782 case SNMP_PDU_TRAP: 783 snmp_printf("%s %s '%s'", types[pdu->type], vers, pdu->community); 784 snmp_printf(" enterprise=%s", asn_oid2str_r(&pdu->enterprise, buf)); 785 snmp_printf(" agent_addr=%u.%u.%u.%u", pdu->agent_addr[0], 786 pdu->agent_addr[1], pdu->agent_addr[2], pdu->agent_addr[3]); 787 snmp_printf(" generic_trap=%d", pdu->generic_trap); 788 snmp_printf(" specific_trap=%d", pdu->specific_trap); 789 snmp_printf(" time-stamp=%u\n", pdu->time_stamp); 790 dump_bindings(pdu); 791 break; 792 793 case SNMP_PDU_GET: 794 case SNMP_PDU_GETNEXT: 795 case SNMP_PDU_RESPONSE: 796 case SNMP_PDU_SET: 797 case SNMP_PDU_GETBULK: 798 case SNMP_PDU_INFORM: 799 case SNMP_PDU_TRAP2: 800 case SNMP_PDU_REPORT: 801 snmp_printf("%s %s '%s'", types[pdu->type], vers, pdu->community); 802 dump_notrap(pdu); 803 break; 804 805 default: 806 snmp_printf("bad pdu type %u\n", pdu->type); 807 break; 808 } 809 } 810 811 void 812 snmp_value_free(struct snmp_value *value) 813 { 814 if (value->syntax == SNMP_SYNTAX_OCTETSTRING) 815 free(value->v.octetstring.octets); 816 value->syntax = SNMP_SYNTAX_NULL; 817 } 818 819 int 820 snmp_value_copy(struct snmp_value *to, const struct snmp_value *from) 821 { 822 to->var = from->var; 823 to->syntax = from->syntax; 824 825 if (from->syntax == SNMP_SYNTAX_OCTETSTRING) { 826 if ((to->v.octetstring.len = from->v.octetstring.len) == 0) 827 to->v.octetstring.octets = NULL; 828 else { 829 to->v.octetstring.octets = malloc(to->v.octetstring.len); 830 if (to->v.octetstring.octets == NULL) 831 return (-1); 832 (void)memcpy(to->v.octetstring.octets, 833 from->v.octetstring.octets, to->v.octetstring.len); 834 } 835 } else 836 to->v = from->v; 837 return (0); 838 } 839 840 void 841 snmp_pdu_free(struct snmp_pdu *pdu) 842 { 843 u_int i; 844 845 for (i = 0; i < pdu->nbindings; i++) 846 snmp_value_free(&pdu->bindings[i]); 847 } 848 849 /* 850 * Parse an ASCII SNMP value into the binary form 851 */ 852 int 853 snmp_value_parse(const char *str, enum snmp_syntax syntax, union snmp_values *v) 854 { 855 char *end; 856 857 switch (syntax) { 858 859 case SNMP_SYNTAX_NULL: 860 case SNMP_SYNTAX_NOSUCHOBJECT: 861 case SNMP_SYNTAX_NOSUCHINSTANCE: 862 case SNMP_SYNTAX_ENDOFMIBVIEW: 863 if (*str != '\0') 864 return (-1); 865 return (0); 866 867 case SNMP_SYNTAX_INTEGER: 868 v->integer = strtoll(str, &end, 0); 869 if (*end != '\0') 870 return (-1); 871 return (0); 872 873 case SNMP_SYNTAX_OCTETSTRING: 874 { 875 u_long len; /* actual length of string */ 876 u_long alloc; /* allocate length of string */ 877 u_char *octs; /* actual octets */ 878 u_long oct; /* actual octet */ 879 u_char *nocts; /* to avoid memory leak */ 880 u_char c; /* actual character */ 881 882 # define STUFFC(C) \ 883 if (alloc == len) { \ 884 alloc += 100; \ 885 if ((nocts = realloc(octs, alloc)) == NULL) { \ 886 free(octs); \ 887 return (-1); \ 888 } \ 889 octs = nocts; \ 890 } \ 891 octs[len++] = (C); 892 893 len = alloc = 0; 894 octs = NULL; 895 896 if (*str == '"') { 897 str++; 898 while((c = *str++) != '\0') { 899 if (c == '"') { 900 if (*str != '\0') { 901 free(octs); 902 return (-1); 903 } 904 break; 905 } 906 if (c == '\\') { 907 switch (c = *str++) { 908 909 case '\\': 910 break; 911 case 'a': 912 c = '\a'; 913 break; 914 case 'b': 915 c = '\b'; 916 break; 917 case 'f': 918 c = '\f'; 919 break; 920 case 'n': 921 c = '\n'; 922 break; 923 case 'r': 924 c = '\r'; 925 break; 926 case 't': 927 c = '\t'; 928 break; 929 case 'v': 930 c = '\v'; 931 break; 932 case 'x': 933 c = 0; 934 if (!isxdigit(*str)) 935 break; 936 if (isdigit(*str)) 937 c = *str++ - '0'; 938 else if (isupper(*str)) 939 c = *str++ - 'A' + 10; 940 else 941 c = *str++ - 'a' + 10; 942 if (!isxdigit(*str)) 943 break; 944 if (isdigit(*str)) 945 c += *str++ - '0'; 946 else if (isupper(*str)) 947 c += *str++ - 'A' + 10; 948 else 949 c += *str++ - 'a' + 10; 950 break; 951 case '0': case '1': case '2': 952 case '3': case '4': case '5': 953 case '6': case '7': 954 c = *str++ - '0'; 955 if (*str < '0' || *str > '7') 956 break; 957 c = *str++ - '0'; 958 if (*str < '0' || *str > '7') 959 break; 960 c = *str++ - '0'; 961 break; 962 default: 963 break; 964 } 965 } 966 STUFFC(c); 967 } 968 } else { 969 while (*str != '\0') { 970 oct = strtoul(str, &end, 16); 971 str = end; 972 if (oct > 0xff) { 973 free(octs); 974 return (-1); 975 } 976 STUFFC(oct); 977 if (*str == ':') 978 str++; 979 else if(*str != '\0') { 980 free(octs); 981 return (-1); 982 } 983 } 984 } 985 v->octetstring.octets = octs; 986 v->octetstring.len = len; 987 return (0); 988 # undef STUFFC 989 } 990 991 case SNMP_SYNTAX_OID: 992 { 993 u_long subid; 994 995 v->oid.len = 0; 996 997 for (;;) { 998 if (v->oid.len == ASN_MAXOIDLEN) 999 return (-1); 1000 subid = strtoul(str, &end, 10); 1001 str = end; 1002 if (subid > ASN_MAXID) 1003 return (-1); 1004 v->oid.subs[v->oid.len++] = (asn_subid_t)subid; 1005 if (*str == '\0') 1006 break; 1007 if (*str != '.') 1008 return (-1); 1009 str++; 1010 } 1011 return (0); 1012 } 1013 1014 case SNMP_SYNTAX_IPADDRESS: 1015 { 1016 struct hostent *he; 1017 u_long ip[4]; 1018 int n; 1019 1020 if (sscanf(str, "%lu.%lu.%lu.%lu%n", &ip[0], &ip[1], &ip[2], 1021 &ip[3], &n) == 4 && (size_t)n == strlen(str) && 1022 ip[0] <= 0xff && ip[1] <= 0xff && 1023 ip[2] <= 0xff && ip[3] <= 0xff) { 1024 v->ipaddress[0] = (u_char)ip[0]; 1025 v->ipaddress[1] = (u_char)ip[1]; 1026 v->ipaddress[2] = (u_char)ip[2]; 1027 v->ipaddress[3] = (u_char)ip[3]; 1028 return (0); 1029 } 1030 1031 if ((he = gethostbyname(str)) == NULL) 1032 return (-1); 1033 if (he->h_addrtype != AF_INET) 1034 return (-1); 1035 1036 v->ipaddress[0] = he->h_addr[0]; 1037 v->ipaddress[1] = he->h_addr[1]; 1038 v->ipaddress[2] = he->h_addr[2]; 1039 v->ipaddress[3] = he->h_addr[3]; 1040 return (0); 1041 } 1042 1043 case SNMP_SYNTAX_COUNTER: 1044 case SNMP_SYNTAX_GAUGE: 1045 case SNMP_SYNTAX_TIMETICKS: 1046 { 1047 uint64_t sub; 1048 1049 sub = strtoull(str, &end, 0); 1050 if (*end != '\0' || sub > 0xffffffff) 1051 return (-1); 1052 v->uint32 = (uint32_t)sub; 1053 return (0); 1054 } 1055 1056 case SNMP_SYNTAX_COUNTER64: 1057 v->counter64 = strtoull(str, &end, 0); 1058 if (*end != '\0') 1059 return (-1); 1060 return (0); 1061 } 1062 abort(); 1063 } 1064 1065 static void 1066 snmp_error_func(const char *fmt, ...) 1067 { 1068 va_list ap; 1069 1070 va_start(ap, fmt); 1071 fprintf(stderr, "SNMP: "); 1072 vfprintf(stderr, fmt, ap); 1073 fprintf(stderr, "\n"); 1074 va_end(ap); 1075 } 1076 1077 static void 1078 snmp_printf_func(const char *fmt, ...) 1079 { 1080 va_list ap; 1081 1082 va_start(ap, fmt); 1083 vfprintf(stderr, fmt, ap); 1084 va_end(ap); 1085 } 1086