17c478bd9Sstevel@tonic-gate /* 27c478bd9Sstevel@tonic-gate * src/lib/krb5/asn.1/asn1_get.c 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * Copyright 1994 by the Massachusetts Institute of Technology. 57c478bd9Sstevel@tonic-gate * All Rights Reserved. 67c478bd9Sstevel@tonic-gate * 77c478bd9Sstevel@tonic-gate * Export of this software from the United States of America may 87c478bd9Sstevel@tonic-gate * require a specific license from the United States Government. 97c478bd9Sstevel@tonic-gate * It is the responsibility of any person or organization contemplating 107c478bd9Sstevel@tonic-gate * export to obtain such a license before exporting. 117c478bd9Sstevel@tonic-gate * 127c478bd9Sstevel@tonic-gate * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and 137c478bd9Sstevel@tonic-gate * distribute this software and its documentation for any purpose and 147c478bd9Sstevel@tonic-gate * without fee is hereby granted, provided that the above copyright 157c478bd9Sstevel@tonic-gate * notice appear in all copies and that both that copyright notice and 167c478bd9Sstevel@tonic-gate * this permission notice appear in supporting documentation, and that 177c478bd9Sstevel@tonic-gate * the name of M.I.T. not be used in advertising or publicity pertaining 187c478bd9Sstevel@tonic-gate * to distribution of the software without specific, written prior 197c478bd9Sstevel@tonic-gate * permission. Furthermore if you modify this software you must label 207c478bd9Sstevel@tonic-gate * your software as modified software and not distribute it in such a 217c478bd9Sstevel@tonic-gate * fashion that it might be confused with the original M.I.T. software. 227c478bd9Sstevel@tonic-gate * M.I.T. makes no representations about the suitability of 237c478bd9Sstevel@tonic-gate * this software for any purpose. It is provided "as is" without express 247c478bd9Sstevel@tonic-gate * or implied warranty. 257c478bd9Sstevel@tonic-gate */ 267c478bd9Sstevel@tonic-gate 277c478bd9Sstevel@tonic-gate #include "asn1_get.h" 287c478bd9Sstevel@tonic-gate 297c478bd9Sstevel@tonic-gate asn1_error_code 307c478bd9Sstevel@tonic-gate asn1_get_tag_2(asn1buf *buf, taginfo *t) 317c478bd9Sstevel@tonic-gate { 327c478bd9Sstevel@tonic-gate asn1_error_code retval; 337c478bd9Sstevel@tonic-gate 347c478bd9Sstevel@tonic-gate if (buf == NULL || buf->base == NULL || 357c478bd9Sstevel@tonic-gate buf->bound - buf->next + 1 <= 0) { 367c478bd9Sstevel@tonic-gate t->tagnum = ASN1_TAGNUM_CEILING; /* emphatically not an EOC tag */ 377c478bd9Sstevel@tonic-gate t->asn1class = UNIVERSAL; 387c478bd9Sstevel@tonic-gate t->construction = PRIMITIVE; 397c478bd9Sstevel@tonic-gate t->length = 0; 407c478bd9Sstevel@tonic-gate t->indef = 0; 417c478bd9Sstevel@tonic-gate return 0; 427c478bd9Sstevel@tonic-gate } 437c478bd9Sstevel@tonic-gate { 447c478bd9Sstevel@tonic-gate /* asn1_get_id(buf, t) */ 457c478bd9Sstevel@tonic-gate asn1_tagnum tn=0; 467c478bd9Sstevel@tonic-gate asn1_octet o; 477c478bd9Sstevel@tonic-gate 487c478bd9Sstevel@tonic-gate #define ASN1_CLASS_MASK 0xC0 497c478bd9Sstevel@tonic-gate #define ASN1_CONSTRUCTION_MASK 0x20 507c478bd9Sstevel@tonic-gate #define ASN1_TAG_NUMBER_MASK 0x1F 517c478bd9Sstevel@tonic-gate 527c478bd9Sstevel@tonic-gate retval = asn1buf_remove_octet(buf,&o); 537c478bd9Sstevel@tonic-gate if (retval) 547c478bd9Sstevel@tonic-gate return retval; 557c478bd9Sstevel@tonic-gate 567c478bd9Sstevel@tonic-gate t->asn1class = (asn1_class)(o&ASN1_CLASS_MASK); 577c478bd9Sstevel@tonic-gate t->construction = (asn1_construction)(o&ASN1_CONSTRUCTION_MASK); 587c478bd9Sstevel@tonic-gate if ((o&ASN1_TAG_NUMBER_MASK) != ASN1_TAG_NUMBER_MASK){ 597c478bd9Sstevel@tonic-gate /* low-tag-number form */ 607c478bd9Sstevel@tonic-gate t->tagnum = (asn1_tagnum)(o&ASN1_TAG_NUMBER_MASK); 617c478bd9Sstevel@tonic-gate } else { 627c478bd9Sstevel@tonic-gate /* high-tag-number form */ 637c478bd9Sstevel@tonic-gate do { 647c478bd9Sstevel@tonic-gate retval = asn1buf_remove_octet(buf,&o); 657c478bd9Sstevel@tonic-gate if (retval) return retval; 667c478bd9Sstevel@tonic-gate tn = (tn<<7) + (asn1_tagnum)(o&0x7F); 67*159d09a2SMark Phalan }while(o&0x80); 687c478bd9Sstevel@tonic-gate t->tagnum = tn; 697c478bd9Sstevel@tonic-gate } 707c478bd9Sstevel@tonic-gate } 717c478bd9Sstevel@tonic-gate 727c478bd9Sstevel@tonic-gate { 737c478bd9Sstevel@tonic-gate /* asn1_get_length(buf, t) */ 747c478bd9Sstevel@tonic-gate asn1_octet o; 757c478bd9Sstevel@tonic-gate 767c478bd9Sstevel@tonic-gate t->indef = 0; 777c478bd9Sstevel@tonic-gate retval = asn1buf_remove_octet(buf,&o); 787c478bd9Sstevel@tonic-gate if (retval) return retval; 797c478bd9Sstevel@tonic-gate if ((o&0x80) == 0) { 807c478bd9Sstevel@tonic-gate t->length = (int)(o&0x7F); 817c478bd9Sstevel@tonic-gate } else { 827c478bd9Sstevel@tonic-gate int num; 837c478bd9Sstevel@tonic-gate int len=0; 847c478bd9Sstevel@tonic-gate 857c478bd9Sstevel@tonic-gate for (num = (int)(o&0x7F); num>0; num--) { 867c478bd9Sstevel@tonic-gate retval = asn1buf_remove_octet(buf,&o); 877c478bd9Sstevel@tonic-gate if(retval) return retval; 887c478bd9Sstevel@tonic-gate len = (len<<8) + (int)o; 897c478bd9Sstevel@tonic-gate } 907c478bd9Sstevel@tonic-gate if (len < 0) 917c478bd9Sstevel@tonic-gate return ASN1_OVERRUN; 927c478bd9Sstevel@tonic-gate if (!len) 937c478bd9Sstevel@tonic-gate t->indef = 1; 947c478bd9Sstevel@tonic-gate t->length = len; 957c478bd9Sstevel@tonic-gate } 967c478bd9Sstevel@tonic-gate } 977c478bd9Sstevel@tonic-gate if (t->indef && t->construction != CONSTRUCTED) 987c478bd9Sstevel@tonic-gate return ASN1_MISMATCH_INDEF; 997c478bd9Sstevel@tonic-gate return 0; 1007c478bd9Sstevel@tonic-gate } 1017c478bd9Sstevel@tonic-gate 1027c478bd9Sstevel@tonic-gate asn1_error_code asn1_get_sequence(asn1buf *buf, unsigned int *retlen, int *indef) 1037c478bd9Sstevel@tonic-gate { 1047c478bd9Sstevel@tonic-gate taginfo t; 1057c478bd9Sstevel@tonic-gate asn1_error_code retval; 1067c478bd9Sstevel@tonic-gate 1077c478bd9Sstevel@tonic-gate retval = asn1_get_tag_2(buf, &t); 1087c478bd9Sstevel@tonic-gate if (retval) 1097c478bd9Sstevel@tonic-gate return retval; 1107c478bd9Sstevel@tonic-gate if (t.asn1class != UNIVERSAL || t.construction != CONSTRUCTED || 1117c478bd9Sstevel@tonic-gate t.tagnum != ASN1_SEQUENCE) 1127c478bd9Sstevel@tonic-gate return ASN1_BAD_ID; 1137c478bd9Sstevel@tonic-gate if (retlen) 1147c478bd9Sstevel@tonic-gate *retlen = t.length; 1157c478bd9Sstevel@tonic-gate if (indef) 1167c478bd9Sstevel@tonic-gate *indef = t.indef; 1177c478bd9Sstevel@tonic-gate return 0; 1187c478bd9Sstevel@tonic-gate } 119