/* * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved. * * The contents of this file constitute Original Code as defined in and are * subject to the Apple Public Source License Version 1.2 (the 'License'). * You may not use this file except in compliance with the License. Please obtain * a copy of the License at http://www.apple.com/publicsource and read it before * using this file. * * This Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the * specific language governing rights and limitations under the License. */ // file: .../c++-lib/src/asn-tag.C - ASN.1 tag manipulation routines // // MS 92/06/18 // Copyright (C) 1992 Michael Sample and the University of British Columbia // // This library is free software; you can redistribute it and/or // modify it provided that this copyright/license information is retained // in original form. // // If you modify this file, you must clearly indicate your changes. // // This source code is distributed in the hope that it will be // useful, but WITHOUT ANY WARRANTY; without even the implied warranty // of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. // #include "asn-config.h" #include "asn-len.h" #include "asn-tag.h" /* * Decode a BER Tag from the given buffer. Error is * flagged if the tag is too long or if a read error occurs. */ AsnTag BDecTag (BUF_TYPE b, AsnLen &bytesDecoded, ENV_TYPE env) { AsnTag tagId; AsnTag tmpTagId; unsigned i; tagId = ((AsnTag) b.GetByte()) << ((sizeof (AsnTag)-1) *8); bytesDecoded++; /* check if long tag format (ie code > 31) */ if ((tagId & (((AsnTag) 0x1f) << ((sizeof (AsnTag)-1)*8))) == (((AsnTag)0x1f) << ((sizeof (AsnTag)-1)*8))) { i = 2; do { tmpTagId = (AsnTag) b.GetByte(); tagId |= (tmpTagId << ((sizeof (AsnTag)-i)*8)); bytesDecoded++; i++; } while ((tmpTagId & (AsnTag)0x80) && (i <= sizeof (AsnTag))); /* * check for too long a tag */ if (i > (sizeof (AsnTag)+1)) { Asn1Error << "BDecTag: ERROR - tag value overflow" << endl; #if SNACC_EXCEPTION_ENABLE SnaccExcep::throwMe(-21); #else longjmp (env, -21); #endif } } if (b.ReadError()) { Asn1Error << "BDecTag: ERROR - decoded past the end of data" << endl; #if SNACC_EXCEPTION_ENABLE SnaccExcep::throwMe(-22); #else longjmp (env, -22); #endif } return tagId; } /* BDecTag */