1 /*
2 * src/lib/krb5/asn.1/asn1_make.c
3 *
4 * Copyright 1994 by the Massachusetts Institute of Technology.
5 * All Rights Reserved.
6 *
7 * Export of this software from the United States of America may
8 * require a specific license from the United States Government.
9 * It is the responsibility of any person or organization contemplating
10 * export to obtain such a license before exporting.
11 *
12 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
13 * distribute this software and its documentation for any purpose and
14 * without fee is hereby granted, provided that the above copyright
15 * notice appear in all copies and that both that copyright notice and
16 * this permission notice appear in supporting documentation, and that
17 * the name of M.I.T. not be used in advertising or publicity pertaining
18 * to distribution of the software without specific, written prior
19 * permission. Furthermore if you modify this software you must label
20 * your software as modified software and not distribute it in such a
21 * fashion that it might be confused with the original M.I.T. software.
22 * M.I.T. makes no representations about the suitability of
23 * this software for any purpose. It is provided "as is" without express
24 * or implied warranty.
25 */
26
27 #include "asn1_make.h"
28
asn1_make_etag(asn1buf * buf,asn1_class asn1class,asn1_tagnum tagnum,unsigned int in_len,unsigned int * retlen)29 asn1_error_code asn1_make_etag(asn1buf *buf, asn1_class asn1class,
30 asn1_tagnum tagnum, unsigned int in_len,
31 unsigned int *retlen)
32 {
33 return asn1_make_tag(buf,asn1class,CONSTRUCTED,tagnum,in_len,retlen);
34 }
35
36
asn1_make_tag(asn1buf * buf,asn1_class asn1class,asn1_construction construction,asn1_tagnum tagnum,unsigned int in_len,unsigned int * retlen)37 asn1_error_code asn1_make_tag(asn1buf *buf, asn1_class asn1class,
38 asn1_construction construction,
39 asn1_tagnum tagnum, unsigned int in_len,
40 unsigned int *retlen)
41 {
42 asn1_error_code retval;
43 unsigned int sumlen=0, length;
44
45 if(tagnum > ASN1_TAGNUM_MAX) return ASN1_OVERFLOW;
46
47 retval = asn1_make_length(buf,in_len, &length);
48 if(retval) return retval;
49 sumlen += length;
50 retval = asn1_make_id(buf,asn1class,construction,tagnum,&length);
51 if(retval) return retval;
52 sumlen += length;
53
54 *retlen = sumlen;
55 return 0;
56 }
57
asn1_make_length(asn1buf * buf,const unsigned int in_len,unsigned int * retlen)58 asn1_error_code asn1_make_length(asn1buf *buf, const unsigned int in_len, unsigned int *retlen)
59 {
60 asn1_error_code retval;
61
62 if(in_len < 128){
63 retval = asn1buf_insert_octet(buf, (asn1_octet)(in_len&0x7F));
64 if(retval) return retval;
65 *retlen = 1;
66 }else{
67 int in_copy=in_len, length=0;
68
69 while(in_copy != 0){
70 retval = asn1buf_insert_octet(buf, (asn1_octet)(in_copy&0xFF));
71 if(retval) return retval;
72 in_copy = in_copy >> 8;
73 length++;
74 }
75 retval = asn1buf_insert_octet(buf, (asn1_octet) (0x80 | (asn1_octet)(length&0x7F)));
76 if(retval) return retval;
77 length++;
78 *retlen = length;
79 }
80
81 return 0;
82 }
83
asn1_make_id(asn1buf * buf,asn1_class asn1class,asn1_construction construction,asn1_tagnum tagnum,unsigned int * retlen)84 asn1_error_code asn1_make_id(asn1buf *buf, asn1_class asn1class,
85 asn1_construction construction,
86 asn1_tagnum tagnum, unsigned int *retlen)
87 {
88 asn1_error_code retval;
89
90 if(tagnum < 31) {
91 retval = asn1buf_insert_octet(buf, (asn1_octet) (asn1class | construction |
92 (asn1_octet)tagnum));
93 if(retval) return retval;
94 *retlen = 1;
95 }else{
96 asn1_tagnum tagcopy = tagnum;
97 int length = 0;
98
99 retval = asn1buf_insert_octet(buf, (asn1_octet)(tagcopy&0x7F));
100 if(retval) return retval;
101 tagcopy >>= 7;
102 length++;
103
104 for(; tagcopy != 0; tagcopy >>= 7){
105 retval = asn1buf_insert_octet(buf, (asn1_octet) (0x80 | (asn1_octet)(tagcopy&0x7F)));
106 if(retval) return retval;
107 length++;
108 }
109
110 retval = asn1buf_insert_octet(buf, (asn1_octet) (asn1class | construction | 0x1F));
111 if(retval) return retval;
112 length++;
113 *retlen = length;
114 }
115
116 return 0;
117 }
118
asn1_make_sequence(asn1buf * buf,const unsigned int seq_len,unsigned int * retlen)119 asn1_error_code asn1_make_sequence(asn1buf *buf, const unsigned int seq_len, unsigned int *retlen)
120 {
121 asn1_error_code retval;
122 unsigned int len, sum=0;
123
124 retval = asn1_make_length(buf,seq_len,&len);
125 if(retval) return retval;
126 sum += len;
127 retval = asn1_make_id(buf,UNIVERSAL,CONSTRUCTED,ASN1_SEQUENCE,&len);
128 if(retval) return retval;
129 sum += len;
130
131 *retlen = sum;
132 return 0;
133 }
134
asn1_make_set(asn1buf * buf,const unsigned int set_len,unsigned int * retlen)135 asn1_error_code asn1_make_set(asn1buf *buf, const unsigned int set_len, unsigned int *retlen)
136 {
137 asn1_error_code retval;
138 unsigned int len, sum=0;
139
140 retval = asn1_make_length(buf,set_len,&len);
141 if(retval) return retval;
142 sum += len;
143 retval = asn1_make_id(buf,UNIVERSAL,CONSTRUCTED,ASN1_SET,&len);
144 if(retval) return retval;
145 sum += len;
146
147 *retlen = sum;
148 return 0;
149 }
150
asn1_make_string(asn1buf * buf,const unsigned int length,const char * string,int * retlen)151 asn1_error_code asn1_make_string(asn1buf *buf, const unsigned int length, const char *string, int *retlen)
152 {
153 asn1_error_code retval;
154
155 retval = asn1buf_insert_charstring(buf,length,string);
156 if(retval) return retval;
157
158 *retlen = length;
159 return 0;
160 }
161