OSX/libsecurity_keychain/libDER/libDER/DER_Encode.h

   1 /*
   2  * Copyright (c) 2005-2016 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24
  25 /*
  26  * DER_Encode.h - DER encoding routines
  27  *
  28  */
  29
  30 #ifndef _DER_ENCODE_H_
  31 #define _DER_ENCODE_H_
  32
  33 #include <libDER/libDER.h>
  34
  35 __BEGIN_DECLS
  36
  37 /*
  38  * Max size of an encoded item given its length.
  39  * This includes a possible leading zero prepended to a signed integer
  40  * (see DER_ENC_SIGNED_INT below).
  41  */
  42 #define DER_MAX_ENCODED_SIZE(len)                                       \
  43         ( 1 +                   /* tag */                                               \
  44           5 +                   /* max length */                                \
  45           1 +                   /* possible prepended zero */   \
  46           len)
  47
  48 /* calculate size of encoded length */
  49 DERSize DERLengthOfLength(
  50         DERSize length);
  51
  52 /* encode length */
  53 DERReturn DEREncodeLength(
  54         DERSize length,
  55         DERByte *buf,           /* encoded length goes here */
  56         DERSize *inOutLen);     /* IN/OUT */
  57
  58 /* calculate size of encoded length */
  59 DERSize DERLengthOfItem(
  60         DERTag tag,
  61         DERSize length);
  62
  63 /* encode item */
  64 DERReturn DEREncodeItem(
  65         DERTag tag,
  66         DERSize length,
  67     const DERByte *src,
  68         DERByte *derOut,        /* encoded item goes here */
  69         DERSize *inOutLen);     /* IN/OUT */
  70
  71 /*
  72  * Per-item encode options.
  73  */
  74
  75 /* explicit default, no options */
  76 #define DER_ENC_NO_OPTS                 0x0000
  77
  78 /* signed integer check: if incoming m.s. bit is 1, prepend a zero */
  79 #define DER_ENC_SIGNED_INT              0x0100
  80
  81 /* DERItem contains fully encoded item - copy, don't encode */
  82 #define DER_ENC_WRITE_DER               0x0200
  83
  84
  85 /*
  86  * High-level sequence or set encode support.
  87  *
  88  * The outgoing sequence is expressed as an array of DERItemSpecs, each
  89  * of which corresponds to one item in the encoded sequence.
  90  *
  91  * Normally the tag of the encoded item comes from the associated
  92  * DERItemSpec, and the content comes from the DERItem whose address is
  93  * the src arg plus the offset value in the associated DERItemSpec.
  94  *
  95  * If the DER_ENC_WRITE_DER option is true for a given DERItemSpec then
  96  * no per-item encoding is done; the DER - with tag, length, and content -
  97  * is taken en masse from the associated DERItem.
  98  */
  99 DERReturn DEREncodeSequence(
 100         DERTag                          topTag,         /* ASN1_CONSTR_SEQUENCE, ASN1_CONSTR_SET */
 101         const void                      *src,           /* generally a ptr to a struct full of
 102                                                                          *    DERItems */
 103         DERShort                        numItems,       /* size of itemSpecs[] */
 104         const DERItemSpec       *itemSpecs,
 105         DERByte                         *derOut,        /* encoded data written here */
 106         DERSize                         *inOutLen);     /* IN/OUT */
 107
 108 /* precalculate the length of an encoded sequence. */
 109 DERSize DERLengthOfEncodedSequence(
 110         DERTag                          topTag,         /* ASN1_CONSTR_SEQUENCE, ASN1_CONSTR_SET */
 111         const void                      *src,           /* generally a ptr to a struct full of
 112                                                                          *    DERItems */
 113         DERShort                        numItems,       /* size of itemSpecs[] */
 114         const DERItemSpec       *itemSpecs);
 115
 116
 117 __END_DECLS
 118
 119 #endif  /* _DER_ENCODE_H_ */