1 #ifndef ASN1_H 2 #define ASN1_H 3 4 #include <net-snmp/library/oid.h> 5 6 #ifdef __cplusplus 7 extern "C" { 8 #endif 9 10 #define PARSE_PACKET 0 11 #define DUMP_PACKET 1 12 13 /* 14 * Definitions for Abstract Syntax Notation One, ASN.1 15 * As defined in ISO/IS 8824 and ISO/IS 8825 16 * 17 * 18 */ 19 /*********************************************************** 20 Copyright 1988, 1989 by Carnegie Mellon University 21 22 All Rights Reserved 23 24 Permission to use, copy, modify, and distribute this software and its 25 documentation for any purpose and without fee is hereby granted, 26 provided that the above copyright notice appear in all copies and that 27 both that copyright notice and this permission notice appear in 28 supporting documentation, and that the name of CMU not be 29 used in advertising or publicity pertaining to distribution of the 30 software without specific, written prior permission. 31 32 CMU DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING 33 ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL 34 CMU BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR 35 ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, 36 WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, 37 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 38 SOFTWARE. 39 ******************************************************************/ 40 /* 41 * Portions of this file are copyrighted by: 42 * Copyright (c) 2016 VMware, Inc. All rights reserved. 43 * Use is subject to license terms specified in the COPYING file 44 */ 45 46 #define MIN_OID_LEN 2 47 #define MAX_OID_LEN 128 /* max subid's in an oid */ 48 #ifndef MAX_NAME_LEN /* conflicts with some libraries */ 49 #define MAX_NAME_LEN MAX_OID_LEN /* obsolete. use MAX_OID_LEN */ 50 #endif 51 52 #define OID_LENGTH(x) (sizeof(x)/sizeof(oid)) 53 54 55 #define ASN_BOOLEAN 0x01U 56 #define ASN_INTEGER 0x02U 57 #define ASN_BIT_STR 0x03U 58 #define ASN_OCTET_STR 0x04U 59 #define ASN_NULL 0x05U 60 #define ASN_OBJECT_ID 0x06U 61 #define ASN_SEQUENCE 0x10U 62 #define ASN_SET 0x11U 63 64 #define ASN_UNIVERSAL 0x00U 65 #define ASN_APPLICATION 0x40U 66 #define ASN_CONTEXT 0x80U 67 #define ASN_PRIVATE 0xC0U 68 69 #define ASN_PRIMITIVE 0x00U 70 #define ASN_CONSTRUCTOR 0x20U 71 72 #define ASN_LONG_LEN 0x80U 73 #define ASN_EXTENSION_ID 0x1FU 74 #define ASN_BIT8 0x80U 75 76 #define IS_CONSTRUCTOR(byte) ((byte) & ASN_CONSTRUCTOR) 77 #define IS_EXTENSION_ID(byte) (((byte) & ASN_EXTENSION_ID) == ASN_EXTENSION_ID) 78 79 struct counter64 { 80 u_long high; 81 u_long low; 82 }; 83 84 #ifdef NETSNMP_WITH_OPAQUE_SPECIAL_TYPES 85 typedef struct counter64 integer64; 86 typedef struct counter64 unsigned64; 87 88 /* 89 * The BER inside an OPAQUE is an context specific with a value of 48 (0x30) 90 * plus the "normal" tag. For a Counter64, the tag is 0x46 (i.e., an 91 * applications specific tag with value 6). So the value for a 64 bit 92 * counter is 0x46 + 0x30, or 0x76 (118 base 10). However, values 93 * greater than 30 can not be encoded in one octet. So the first octet 94 * has the class, in this case context specific (ASN_CONTEXT), and 95 * the special value (i.e., 31) to indicate that the real value follows 96 * in one or more octets. The high order bit of each following octet 97 * indicates if the value is encoded in additional octets. A high order 98 * bit of zero, indicates the last. For this "hack", only one octet 99 * will be used for the value. 100 */ 101 102 /* 103 * first octet of the tag 104 */ 105 #define ASN_OPAQUE_TAG1 (ASN_CONTEXT | ASN_EXTENSION_ID) 106 /* 107 * base value for the second octet of the tag - the 108 * second octet was the value for the tag 109 */ 110 #define ASN_OPAQUE_TAG2 0x30U 111 112 #define ASN_OPAQUE_TAG2U 0x2fU /* second octet of tag for union */ 113 114 /* 115 * All the ASN.1 types for SNMP "should have been" defined in this file, 116 * but they were not. (They are defined in snmp_impl.h) Thus, the tag for 117 * Opaque and Counter64 is defined, again, here with a different names. 118 */ 119 #define ASN_APP_OPAQUE (ASN_APPLICATION | 4) 120 #define ASN_APP_COUNTER64 (ASN_APPLICATION | 6) 121 #define ASN_APP_FLOAT (ASN_APPLICATION | 8) 122 #define ASN_APP_DOUBLE (ASN_APPLICATION | 9) 123 #define ASN_APP_I64 (ASN_APPLICATION | 10) 124 #define ASN_APP_U64 (ASN_APPLICATION | 11) 125 #define ASN_APP_UNION (ASN_PRIVATE | 1) /* or ASN_PRIV_UNION ? */ 126 127 /* 128 * value for Counter64 129 */ 130 #define ASN_OPAQUE_COUNTER64 (ASN_OPAQUE_TAG2 + ASN_APP_COUNTER64) 131 /* 132 * max size of BER encoding of Counter64 133 */ 134 #define ASN_OPAQUE_COUNTER64_MX_BER_LEN 12 135 136 /* 137 * value for Float 138 */ 139 #define ASN_OPAQUE_FLOAT (ASN_OPAQUE_TAG2 + ASN_APP_FLOAT) 140 /* 141 * size of BER encoding of Float 142 */ 143 #define ASN_OPAQUE_FLOAT_BER_LEN 7 144 145 /* 146 * value for Double 147 */ 148 #define ASN_OPAQUE_DOUBLE (ASN_OPAQUE_TAG2 + ASN_APP_DOUBLE) 149 /* 150 * size of BER encoding of Double 151 */ 152 #define ASN_OPAQUE_DOUBLE_BER_LEN 11 153 154 /* 155 * value for Integer64 156 */ 157 #define ASN_OPAQUE_I64 (ASN_OPAQUE_TAG2 + ASN_APP_I64) 158 /* 159 * max size of BER encoding of Integer64 160 */ 161 #define ASN_OPAQUE_I64_MX_BER_LEN 11 162 163 /* 164 * value for Unsigned64 165 */ 166 #define ASN_OPAQUE_U64 (ASN_OPAQUE_TAG2 + ASN_APP_U64) 167 /* 168 * max size of BER encoding of Unsigned64 169 */ 170 #define ASN_OPAQUE_U64_MX_BER_LEN 12 171 172 #endif /* NETSNMP_WITH_OPAQUE_SPECIAL_TYPES */ 173 174 175 #define ASN_PRIV_INCL_RANGE (ASN_PRIVATE | 2) 176 #define ASN_PRIV_EXCL_RANGE (ASN_PRIVATE | 3) 177 #define ASN_PRIV_DELEGATED (ASN_PRIVATE | 5) 178 #define ASN_PRIV_IMPLIED_OCTET_STR (ASN_PRIVATE | ASN_OCTET_STR) /* 4 */ 179 #define ASN_PRIV_IMPLIED_OBJECT_ID (ASN_PRIVATE | ASN_OBJECT_ID) /* 6 */ 180 #define ASN_PRIV_RETRY (ASN_PRIVATE | 7) /* 199 */ 181 #define ASN_PRIV_STOP (ASN_PRIVATE | 8) /* 200 */ 182 #define IS_DELEGATED(x) ((x) == ASN_PRIV_DELEGATED) 183 184 185 NETSNMP_IMPORT 186 int asn_check_packet(u_char *, size_t); 187 NETSNMP_IMPORT 188 u_char *asn_parse_int(u_char *, size_t *, u_char *, long *, 189 size_t); 190 NETSNMP_IMPORT 191 u_char *asn_build_int(u_char *, size_t *, u_char, const long *, 192 size_t); 193 NETSNMP_IMPORT 194 u_char *asn_parse_unsigned_int(u_char *, size_t *, u_char *, 195 u_long *, size_t); 196 NETSNMP_IMPORT 197 u_char *asn_build_unsigned_int(u_char *, size_t *, u_char, 198 const u_long *, size_t); 199 NETSNMP_IMPORT 200 u_char *asn_parse_string(u_char *, size_t *, u_char *, 201 u_char *, size_t *); 202 NETSNMP_IMPORT 203 u_char *asn_build_string(u_char *, size_t *, u_char, 204 const u_char *, size_t); 205 NETSNMP_IMPORT 206 u_char *asn_parse_header(u_char *, size_t *, u_char *); 207 NETSNMP_IMPORT 208 u_char *asn_parse_sequence(u_char *, size_t *, u_char *, u_char expected_type, /* must be this type */ 209 const char *estr); /* error message prefix */ 210 NETSNMP_IMPORT 211 u_char *asn_build_header(u_char *, size_t *, u_char, size_t); 212 NETSNMP_IMPORT 213 u_char *asn_build_sequence(u_char *, size_t *, u_char, size_t); 214 NETSNMP_IMPORT 215 u_char *asn_parse_length(u_char *, u_long *); 216 NETSNMP_IMPORT 217 u_char *asn_build_length(u_char *, size_t *, size_t); 218 NETSNMP_IMPORT 219 u_char *asn_parse_objid(u_char *, size_t *, u_char *, oid *, 220 size_t *); 221 NETSNMP_IMPORT 222 u_char *asn_build_objid(u_char *, size_t *, u_char, oid *, 223 size_t); 224 NETSNMP_IMPORT 225 u_char *asn_parse_null(u_char *, size_t *, u_char *); 226 NETSNMP_IMPORT 227 u_char *asn_build_null(u_char *, size_t *, u_char); 228 NETSNMP_IMPORT 229 u_char *asn_parse_bitstring(u_char *, size_t *, u_char *, 230 u_char *, size_t *); 231 NETSNMP_IMPORT 232 u_char *asn_build_bitstring(u_char *, size_t *, u_char, 233 const u_char *, size_t); 234 NETSNMP_IMPORT 235 u_char *asn_parse_unsigned_int64(u_char *, size_t *, u_char *, 236 struct counter64 *, size_t); 237 NETSNMP_IMPORT 238 u_char *asn_build_unsigned_int64(u_char *, size_t *, u_char, 239 const struct counter64 *, size_t); 240 NETSNMP_IMPORT 241 u_char *asn_parse_signed_int64(u_char *, size_t *, u_char *, 242 struct counter64 *, size_t); 243 NETSNMP_IMPORT 244 u_char *asn_build_signed_int64(u_char *, size_t *, u_char, 245 const struct counter64 *, size_t); 246 NETSNMP_IMPORT 247 u_char *asn_build_float(u_char *, size_t *, u_char, const float *, 248 size_t); 249 NETSNMP_IMPORT 250 u_char *asn_parse_float(u_char *, size_t *, u_char *, float *, 251 size_t); 252 NETSNMP_IMPORT 253 u_char *asn_build_double(u_char *, size_t *, u_char, const double *, 254 size_t); 255 NETSNMP_IMPORT 256 u_char *asn_parse_double(u_char *, size_t *, u_char *, 257 double *, size_t); 258 259 #ifdef NETSNMP_USE_REVERSE_ASNENCODING 260 261 /* 262 * Re-allocator function for below. 263 */ 264 265 NETSNMP_IMPORT 266 int asn_realloc(u_char **, size_t *); 267 268 /* 269 * Re-allocating reverse ASN.1 encoder functions. Synopsis: 270 * 271 * u_char *buf = (u_char*)malloc(100); 272 * u_char type = (ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER); 273 * size_t buf_len = 100, offset = 0; 274 * long data = 12345; 275 * int allow_realloc = 1; 276 * 277 * if (asn_realloc_rbuild_int(&buf, &buf_len, &offset, allow_realloc, 278 * type, &data, sizeof(long)) == 0) { 279 * error; 280 * } 281 * 282 * NOTE WELL: after calling one of these functions with allow_realloc 283 * non-zero, buf might have moved, buf_len might have grown and 284 * offset will have increased by the size of the encoded data. 285 * You should **NEVER** do something like this: 286 * 287 * u_char *buf = (u_char *)malloc(100), *ptr; 288 * u_char type = (ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER); 289 * size_t buf_len = 100, offset = 0; 290 * long data1 = 1234, data2 = 5678; 291 * int rc = 0, allow_realloc = 1; 292 * 293 * rc = asn_realloc_rbuild_int(&buf, &buf_len, &offset, allow_realloc, 294 * type, &data1, sizeof(long)); 295 * ptr = buf[buf_len - offset]; / * points at encoding of data1 * / 296 * if (rc == 0) { 297 * error; 298 * } 299 * rc = asn_realloc_rbuild_int(&buf, &buf_len, &offset, allow_realloc, 300 * type, &data2, sizeof(long)); 301 * make use of ptr here; 302 * 303 * 304 * ptr is **INVALID** at this point. In general, you should store the 305 * offset value and compute pointers when you need them: 306 * 307 * 308 * 309 * u_char *buf = (u_char *)malloc(100), *ptr; 310 * u_char type = (ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER); 311 * size_t buf_len = 100, offset = 0, ptr_offset; 312 * long data1 = 1234, data2 = 5678; 313 * int rc = 0, allow_realloc = 1; 314 * 315 * rc = asn_realloc_rbuild_int(&buf, &buf_len, &offset, allow_realloc, 316 * type, &data1, sizeof(long)); 317 * ptr_offset = offset; 318 * if (rc == 0) { 319 * error; 320 * } 321 * rc = asn_realloc_rbuild_int(&buf, &buf_len, &offset, allow_realloc, 322 * type, &data2, sizeof(long)); 323 * ptr = buf + buf_len - ptr_offset 324 * make use of ptr here; 325 * 326 * 327 * 328 * Here, you can see that ptr will be a valid pointer even if the block of 329 * memory has been moved, as it may well have been. Plenty of examples of 330 * usage all over asn1.c, snmp_api.c, snmpusm.c. 331 * 332 * The other thing you should **NEVER** do is to pass a pointer to a buffer 333 * on the stack as the first argument when allow_realloc is non-zero, unless 334 * you really know what you are doing and your machine/compiler allows you to 335 * free non-heap memory. There are rumours that such things exist, but many 336 * consider them no more than the wild tales of a fool. 337 * 338 * Of course, you can pass allow_realloc as zero, to indicate that you do not 339 * wish the packet buffer to be reallocated for some reason; perhaps because 340 * it is on the stack. This may be useful to emulate the functionality of 341 * the old API: 342 * 343 * u_char my_static_buffer[100], *cp = NULL; 344 * size_t my_static_buffer_len = 100; 345 * float my_pi = (float)22/(float)7; 346 * 347 * cp = asn_rbuild_float(my_static_buffer, &my_static_buffer_len, 348 * ASN_OPAQUE_FLOAT, &my_pi, sizeof(float)); 349 * if (cp == NULL) { 350 * error; 351 * } 352 * 353 * 354 * IS EQUIVALENT TO: 355 * 356 * 357 * u_char my_static_buffer[100]; 358 * size_t my_static_buffer_len = 100, my_offset = 0; 359 * float my_pi = (float)22/(float)7; 360 * int rc = 0; 361 * 362 * rc = asn_realloc_rbuild_float(&my_static_buffer, &my_static_buffer_len, 363 * &my_offset, 0, 364 * ASN_OPAQUE_FLOAT, &my_pi, sizeof(float)); 365 * if (rc == 0) { 366 * error; 367 * } 368 * 369 * 370 */ 371 372 373 NETSNMP_IMPORT 374 int asn_realloc_rbuild_int(u_char ** pkt, size_t * pkt_len, 375 size_t * offset, 376 int allow_realloc, u_char type, 377 const long *data, size_t data_size); 378 379 NETSNMP_IMPORT 380 int asn_realloc_rbuild_string(u_char ** pkt, 381 size_t * pkt_len, 382 size_t * offset, 383 int allow_realloc, 384 u_char type, 385 const u_char * data, 386 size_t data_size); 387 388 NETSNMP_IMPORT 389 int asn_realloc_rbuild_unsigned_int(u_char ** pkt, 390 size_t * pkt_len, 391 size_t * offset, 392 int allow_realloc, 393 u_char type, 394 const u_long * data, 395 size_t data_size); 396 397 NETSNMP_IMPORT 398 int asn_realloc_rbuild_header(u_char ** pkt, 399 size_t * pkt_len, 400 size_t * offset, 401 int allow_realloc, 402 u_char type, 403 size_t data_size); 404 405 NETSNMP_IMPORT 406 int asn_realloc_rbuild_sequence(u_char ** pkt, 407 size_t * pkt_len, 408 size_t * offset, 409 int allow_realloc, 410 u_char type, 411 size_t data_size); 412 413 NETSNMP_IMPORT 414 int asn_realloc_rbuild_length(u_char ** pkt, 415 size_t * pkt_len, 416 size_t * offset, 417 int allow_realloc, 418 size_t data_size); 419 420 NETSNMP_IMPORT 421 int asn_realloc_rbuild_objid(u_char ** pkt, 422 size_t * pkt_len, 423 size_t * offset, 424 int allow_realloc, 425 u_char type, const oid *, 426 size_t); 427 428 NETSNMP_IMPORT 429 int asn_realloc_rbuild_null(u_char ** pkt, 430 size_t * pkt_len, 431 size_t * offset, 432 int allow_realloc, 433 u_char type); 434 435 NETSNMP_IMPORT 436 int asn_realloc_rbuild_bitstring(u_char ** pkt, 437 size_t * pkt_len, 438 size_t * offset, 439 int allow_realloc, 440 u_char type, 441 const u_char * data, 442 size_t data_size); 443 444 NETSNMP_IMPORT 445 int asn_realloc_rbuild_unsigned_int64(u_char ** pkt, 446 size_t * pkt_len, 447 size_t * offset, 448 int allow_realloc, 449 u_char type, 450 struct counter64 451 const *data, size_t); 452 453 NETSNMP_IMPORT 454 int asn_realloc_rbuild_signed_int64(u_char ** pkt, 455 size_t * pkt_len, 456 size_t * offset, 457 int allow_realloc, 458 u_char type, 459 const struct counter64 *data, 460 size_t); 461 462 NETSNMP_IMPORT 463 int asn_realloc_rbuild_float(u_char ** pkt, 464 size_t * pkt_len, 465 size_t * offset, 466 int allow_realloc, 467 u_char type, const float *data, 468 size_t data_size); 469 470 NETSNMP_IMPORT 471 int asn_realloc_rbuild_double(u_char ** pkt, 472 size_t * pkt_len, 473 size_t * offset, 474 int allow_realloc, 475 u_char type, const double *data, 476 size_t data_size); 477 #endif 478 479 #ifdef __cplusplus 480 } 481 #endif 482 #endif /* ASN1_H */ 483