1ASN1_GENERATE_NCONF(3) OpenSSL ASN1_GENERATE_NCONF(3)
2
6 ASN1_generate_nconf, ASN1_generate_v3 - ASN1 generation functions
7
9 #include <openssl/asn1.h>
10 ASN1_TYPE *ASN1_generate_nconf(const char *str, CONF *nconf);
12 ASN1_TYPE *ASN1_generate_v3(const char *str, X509V3_CTX *cnf);
13
15 These functions generate the ASN1 encoding of a string in an ASN1_TYPE
16 structure.
17 str contains the string to encode nconf or cnf contains the optional
19 configuration information where additional strings will be read from.
20 nconf will typically come from a config file whereas cnf is obtained
21 from an X509V3_CTX structure which will typically be used by X509 v3
22 certificate extension functions. cnf or nconf can be set to NULL if no
23 additional configuration will be used.
24
26 The actual data encoded is determined by the string str and the
27 configuration information. The general format of the string is:
28 [modifier,]type[:value]
30 That is zero or more comma separated modifiers followed by a type
32 followed by an optional colon and a value. The formats of type, value
33 and modifier are explained below.
34 Supported Types
36 The supported types are listed below. Unless otherwise specified only
37 the ASCII format is permissible.
38 BOOLEAN, BOOL
40 This encodes a boolean type. The value string is mandatory and
41 should be TRUE or FALSE. Additionally TRUE, true, Y, y, YES, yes,
42 FALSE, false, N, n, NO and no are acceptable.
43 NULL
45 Encode the NULL type, the value string must not be present.
46 INTEGER, INT
48 Encodes an ASN1 INTEGER type. The value string represents the value
49 of the integer, it can be prefaced by a minus sign and is normally
50 interpreted as a decimal value unless the prefix 0x is included.
51 ENUMERATED, ENUM
53 Encodes the ASN1 ENUMERATED type, it is otherwise identical to
54 INTEGER.
55 OBJECT, OID
57 Encodes an ASN1 OBJECT IDENTIFIER, the value string can be a short
58 name, a long name or numerical format.
59 UTCTIME, UTC
61 Encodes an ASN1 UTCTime structure, the value should be in the
62 format YYMMDDHHMMSSZ.
63 GENERALIZEDTIME, GENTIME
65 Encodes an ASN1 GeneralizedTime structure, the value should be in
66 the format YYYYMMDDHHMMSSZ.
67 OCTETSTRING, OCT
69 Encodes an ASN1 OCTET STRING. value represents the contents of this
70 structure, the format strings ASCII and HEX can be used to specify
71 the format of value.
72 BITSTRING, BITSTR
74 Encodes an ASN1 BIT STRING. value represents the contents of this
75 structure, the format strings ASCII, HEX and BITLIST can be used to
76 specify the format of value.
77 If the format is anything other than BITLIST the number of unused
79 bits is set to zero.
80 UNIVERSALSTRING, UNIV, IA5, IA5STRING, UTF8, UTF8String, BMP,
82 BMPSTRING, VISIBLESTRING, VISIBLE, PRINTABLESTRING, PRINTABLE, T61,
83 T61STRING, TELETEXSTRING, GeneralString, NUMERICSTRING, NUMERIC
84 These encode the corresponding string types. value represents the
85 contents of this structure. The format can be ASCII or UTF8.
86 SEQUENCE, SEQ, SET
88 Formats the result as an ASN1 SEQUENCE or SET type. value should be
89 a section name which will contain the contents. The field names in
90 the section are ignored and the values are in the generated string
91 format. If value is absent then an empty SEQUENCE will be encoded.
92 Modifiers
94 Modifiers affect the following structure, they can be used to add
95 EXPLICIT or IMPLICIT tagging, add wrappers or to change the string
96 format of the final type and value. The supported formats are
97 documented below.
98 EXPLICIT, EXP
100 Add an explicit tag to the following structure. This string should
101 be followed by a colon and the tag value to use as a decimal value.
102 By following the number with U, A, P or C UNIVERSAL, APPLICATION,
104 PRIVATE or CONTEXT SPECIFIC tagging can be used, the default is
105 CONTEXT SPECIFIC.
106 IMPLICIT, IMP
108 This is the same as EXPLICIT except IMPLICIT tagging is used
109 instead.
110 OCTWRAP, SEQWRAP, SETWRAP, BITWRAP
112 The following structure is surrounded by an OCTET STRING, a
113 SEQUENCE, a SET or a BIT STRING respectively. For a BIT STRING the
114 number of unused bits is set to zero.
115 FORMAT
117 This specifies the format of the ultimate value. It should be
118 followed by a colon and one of the strings ASCII, UTF8, HEX or
119 BITLIST.
120 If no format specifier is included then ASCII is used. If UTF8 is
122 specified then the value string must be a valid UTF8 string. For
123 HEX the output must be a set of hex digits. BITLIST (which is only
124 valid for a BIT STRING) is a comma separated list of the indices of
125 the set bits, all other bits are zero.
126
128 ASN1_generate_nconf() and ASN1_generate_v3() return the encoded data as
129 an ASN1_TYPE structure or NULL if an error occurred.
130 The error codes that can be obtained by ERR_get_error(3).
132
134 A simple IA5String:
135 IA5STRING:Hello World
137 An IA5String explicitly tagged:
139 EXPLICIT:0,IA5STRING:Hello World
141 An IA5String explicitly tagged using APPLICATION tagging:
143 EXPLICIT:0A,IA5STRING:Hello World
145 A BITSTRING with bits 1 and 5 set and all others zero:
147 FORMAT:BITLIST,BITSTRING:1,5
149 A more complex example using a config file to produce a SEQUENCE
151 consisting of a BOOL an OID and a UTF8String:
152 asn1 = SEQUENCE:seq_section
154 [seq_section]
156 field1 = BOOLEAN:TRUE
158 field2 = OID:commonName
159 field3 = UTF8:Third field
160 This example produces an RSAPrivateKey structure, this is the key
162 contained in the file client.pem in all OpenSSL distributions (note:
163 the field names such as 'coeff' are ignored and are present just for
164 clarity):
165 asn1=SEQUENCE:private_key
167 [private_key]
168 version=INTEGER:0
169 n=INTEGER:0xBB6FE79432CC6EA2D8F970675A5A87BFBE1AFF0BE63E879F2AFFB93644\
171 D4D2C6D000430DEC66ABF47829E74B8C5108623A1C0EE8BE217B3AD8D36D5EB4FCA1D9
172 e=INTEGER:0x010001
174 d=INTEGER:0x6F05EAD2F27FFAEC84BEC360C4B928FD5F3A9865D0FCAAD291E2A52F4A\
176 F810DC6373278C006A0ABBA27DC8C63BF97F7E666E27C5284D7D3B1FFFE16B7A87B51D
177 p=INTEGER:0xF3929B9435608F8A22C208D86795271D54EBDFB09DDEF539AB083DA912\
179 D4BD57
180 q=INTEGER:0xC50016F89DFF2561347ED1186A46E150E28BF2D0F539A1594BBD7FE467\
182 46EC4F
183 exp1=INTEGER:0x9E7D4326C924AFC1DEA40B45650134966D6F9DFA3A7F9D698CD4ABEA\
185 9C0A39B9
186 exp2=INTEGER:0xBA84003BB95355AFB7C50DF140C60513D0BA51D637272E355E397779\
188 E7B2458F
189 coeff=INTEGER:0x30B9E4F2AFA5AC679F920FC83F1F2DF1BAF1779CF989447FABC2F5\
191 628657053A
192 This example is the corresponding public key in a SubjectPublicKeyInfo
194 structure:
195 # Start with a SEQUENCE
197 asn1=SEQUENCE:pubkeyinfo
198 # pubkeyinfo contains an algorithm identifier and the public key wrapped
200 # in a BIT STRING
201 [pubkeyinfo]
202 algorithm=SEQUENCE:rsa_alg
203 pubkey=BITWRAP,SEQUENCE:rsapubkey
204 # algorithm ID for RSA is just an OID and a NULL
206 [rsa_alg]
207 algorithm=OID:rsaEncryption
208 parameter=NULL
209 # Actual public key: modulus and exponent
211 [rsapubkey]
212 n=INTEGER:0xBB6FE79432CC6EA2D8F970675A5A87BFBE1AFF0BE63E879F2AFFB93644\
213 D4D2C6D000430DEC66ABF47829E74B8C5108623A1C0EE8BE217B3AD8D36D5EB4FCA1D9
214 e=INTEGER:0x010001
216
218 ERR_get_error(3)
219
221 Copyright 2002-2019 The OpenSSL Project Authors. All Rights Reserved.
222 Licensed under the OpenSSL license (the "License"). You may not use
224 this file except in compliance with the License. You can obtain a copy
225 in the file LICENSE in the source distribution or at
226 <https://www.openssl.org/source/license.html>.
2271.1.1q 2023-02-06 ASN1_GENERATE_NCONF(3)