1ASN1_generate_nconf(3) OpenSSL ASN1_generate_nconf(3)
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6 ASN1_generate_nconf, ASN1_generate_v3 - ASN1 generation functions
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9 ASN1_TYPE *ASN1_generate_nconf(char *str, CONF *nconf);
10 ASN1_TYPE *ASN1_generate_v3(char *str, X509V3_CTX *cnf);
11
13 These functions generate the ASN1 encoding of a string in an ASN1_TYPE
14 structure.
15 str contains the string to encode nconf or cnf contains the optional
17 configuration information where additional strings will be read from.
18 nconf will typically come from a config file wherease cnf is obtained
19 from an X509V3_CTX structure which will typically be used by X509 v3
20 certificate extension functions. cnf or nconf can be set to NULL if no
21 additional configuration will be used.
22
24 The actual data encoded is determined by the string str and the config‐
25 uration information. The general format of the string is:
26 B<[modifier,]type[:value]>
28 That is zero or more comma separated modifiers followed by a type fol‐
30 lowed by an optional colon and a value. The formats of type, value and
31 modifier are explained below.
32 SUPPORTED TYPES
34 The supported types are listed below. Unless otherwise specified only
36 the ASCII format is permissible.
37 BOOLEAN, BOOL
39 This encodes a boolean type. The value string is mandatory and should
40 be TRUE or FALSE. Additionally TRUE, true, Y, y, YES, yes, FALSE,
41 false, N, n, NO and no are acceptable.
42 NULL
44 Encode the NULL type, the value string must not be present.
45 INTEGER, INT
47 Encodes an ASN1 INTEGER type. The value string represents the value
48 of the integer, it can be preceeded by a minus sign and is normally
49 interpreted as a decimal value unless the prefix 0x is included.
50 ENUMERATED, ENUM
52 Encodes the ASN1 ENUMERATED type, it is otherwise identical to INTE‐
53 GER.
54 OBJECT, OID
56 Encodes an ASN1 OBJECT IDENTIFIER, the value string can be a short
57 name, a long name or numerical format.
58 UTCTIME, UTC
60 Encodes an ASN1 UTCTime structure, the value should be in the format
61 YYMMDDHHMMSSZ.
62 GENERALIZEDTIME, GENTIME
64 Encodes an ASN1 GeneralizedTime structure, the value should be in the
65 format YYYYMMDDHHMMSSZ.
66 OCTETSTRING, OCT
68 Emcodes an ASN1 OCTET STRING. value represents the contents of this
69 structure, the format strings ASCII and HEX can be used to specify
70 the format of value.
71 BITSRING, BITSTR
73 Emcodes an ASN1 BIT STRING. value represents the contents of this
74 structure, the format strings ASCII, HEX and BITLIST can be used to
75 specify the format of value.
76 If the format is anything other than BITLIST the number of unused
78 bits is set to zero.
79 UNIVERSALSTRING, UNIV, IA5, IA5STRING, UTF8, UTF8String, BMP, BMP‐
81 STRING, VISIBLESTRING, VISIBLE, PRINTABLESTRING, PRINTABLE, T61,
82 T61STRING, TELETEXSTRING, GeneralString
83 These encode the corresponding string types. value represents the
84 contents of this structure. The format can be ASCII or UTF8.
85 SEQUENCE, SEQ, SET
87 Formats the result as an ASN1 SEQUENCE or SET type. value should be a
88 section name which will contain the contents. The field names in the
89 section are ignored and the values are in the generated string for‐
90 mat. If value is absent then an empty SEQUENCE will be encoded.
91 MODIFIERS
93 Modifiers affect the following structure, they can be used to add
95 EXPLICIT or IMPLICIT tagging, add wrappers or to change the string for‐
96 mat of the final type and value. The supported formats are documented
97 below.
98 EXPLICIT, EXP
100 Add an explicit tag to the following structure. This string should be
101 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 CON‐
105 TEXT SPECIFIC.
106 IMPLICIT, IMP
108 This is the same as EXPLICIT except IMPLICIT tagging is used instead.
109 OCTWRAP, SEQWRAP, SETWRAP, BITWRAP
111 The following structure is surrounded by an OCTET STRING, a SEQUENCE,
112 a SET or a BIT STRING respectively. For a BIT STRING the number of
113 unused bits is set to zero.
114 FORMAT
116 This specifies the format of the ultimate value. It should be fol‐
117 lowed by a colon and one of the strings ASCII, UTF8, HEX or BITLIST.
118 If no format specifier is included then ASCII is used. If UTF8 is
120 specified then the value string must be a valid UTF8 string. For HEX
121 the output must be a set of hex digits. BITLIST (which is only valid
122 for a BIT STRING) is a comma separated list of set bits.
123
125 A simple IA5String:
126 IA5STRING:Hello World
128 An IA5String explicitly tagged:
130 EXPLICIT:0,IA5STRING:Hello World
132 An IA5String explicitly tagged using APPLICATION tagging:
134 EXPLICIT:0A,IA5STRING:Hello World
136 A more complex example using a config file to produce a SEQUENCE con‐
138 siting of a BOOL an OID and a UTF8String:
139 asn1 = SEQUENCE:seq_section
141 [seq_section]
143 field1 = BOOLEAN:TRUE field2 = OID:commonName field3 = UTF8:Third field
145 This example produces an RSAPrivateKey structure, this is the key con‐
147 tained in the file client.pem in all OpenSSL distributions (note: the
148 field names such as 'coeff' are ignored and are present just for clar‐
149 ity):
150 asn1=SEQUENCE:private_key
152 [private_key]
153 version=INTEGER:0
154 n=INTEGER:0xBB6FE79432CC6EA2D8F970675A5A87BFBE1AFF0BE63E879F2AFFB93644\
156 D4D2C6D000430DEC66ABF47829E74B8C5108623A1C0EE8BE217B3AD8D36D5EB4FCA1D9
157 e=INTEGER:0x010001
159 d=INTEGER:0x6F05EAD2F27FFAEC84BEC360C4B928FD5F3A9865D0FCAAD291E2A52F4A\
161 F810DC6373278C006A0ABBA27DC8C63BF97F7E666E27C5284D7D3B1FFFE16B7A87B51D
162 p=INTEGER:0xF3929B9435608F8A22C208D86795271D54EBDFB09DDEF539AB083DA912\
164 D4BD57
165 q=INTEGER:0xC50016F89DFF2561347ED1186A46E150E28BF2D0F539A1594BBD7FE467\
167 46EC4F
168 exp1=INTEGER:0x9E7D4326C924AFC1DEA40B45650134966D6F9DFA3A7F9D698CD4ABEA\
170 9C0A39B9
171 exp2=INTEGER:0xBA84003BB95355AFB7C50DF140C60513D0BA51D637272E355E397779\
173 E7B2458F
174 coeff=INTEGER:0x30B9E4F2AFA5AC679F920FC83F1F2DF1BAF1779CF989447FABC2F5\
176 628657053A
177 This example is the corresponding public key in a SubjectPublicKeyInfo
179 structure:
180 # Start with a SEQUENCE
182 asn1=SEQUENCE:pubkeyinfo
183 # pubkeyinfo contains an algorithm identifier and the public key wrapped
185 # in a BIT STRING
186 [pubkeyinfo]
187 algorithm=SEQUENCE:rsa_alg
188 pubkey=BITWRAP,SEQUENCE:rsapubkey
189 # algorithm ID for RSA is just an OID and a NULL
191 [rsa_alg]
192 algorithm=OID:rsaEncryption
193 parameter=NULL
194 # Actual public key: modulus and exponent
196 [rsapubkey]
197 n=INTEGER:0xBB6FE79432CC6EA2D8F970675A5A87BFBE1AFF0BE63E879F2AFFB93644\
198 D4D2C6D000430DEC66ABF47829E74B8C5108623A1C0EE8BE217B3AD8D36D5EB4FCA1D9
199 e=INTEGER:0x010001
201
203 ASN1_generate_nconf() and ASN1_generate_v3() return the encoded data as
204 an ASN1_TYPE structure or NULL if an error occurred.
205 The error codes that can be obtained by ERR_get_error(3).
207
209 ERR_get_error(3)
210
212 ASN1_generate_nconf() and ASN1_generate_v3() were added to OpenSSL
213 0.9.8
2140.9.8b 2003-02-11 ASN1_generate_nconf(3)