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ASN1_generate_nconf(3)		    OpenSSL		ASN1_generate_nconf(3)



NAME
       ASN1_generate_nconf, ASN1_generate_v3 - ASN1 generation functions

SYNOPSIS
	#include <openssl/asn1.h>

	ASN1_TYPE *ASN1_generate_nconf(char *str, CONF *nconf);
	ASN1_TYPE *ASN1_generate_v3(char *str, X509V3_CTX *cnf);

DESCRIPTION
       These functions generate the ASN1 encoding of a string in an ASN1_TYPE
       structure.

       str contains the string to encode nconf or cnf contains the optional
       configuration information where additional strings will be read from.
       nconf will typically come from a config file wherease cnf is obtained
       from an X509V3_CTX structure which will typically be used by X509 v3
       certificate extension functions. cnf or nconf can be set to NULL if no
       additional configuration will be used.

GENERATION STRING FORMAT
       The actual data encoded is determined by the string str and the
       configuration information. The general format of the string is:

       [modifier,]type[:value]

       That is zero or more comma separated modifiers followed by a type
       followed by an optional colon and a value. The formats of type, value
       and modifier are explained below.

   SUPPORTED TYPES
       The supported types are listed below. Unless otherwise specified only
       the ASCII format is permissible.

       BOOLEAN, BOOL
	 This encodes a boolean type. The value string is mandatory and should
	 be TRUE or FALSE. Additionally TRUE, true, Y, y, YES, yes, FALSE,
	 false, N, n, NO and no are acceptable.

       NULL
	 Encode the NULL type, the value string must not be present.

       INTEGER, INT
	 Encodes an ASN1 INTEGER type. The value string represents the value
	 of the integer, it can be prefaced by a minus sign and is normally
	 interpreted as a decimal value unless the prefix 0x is included.

       ENUMERATED, ENUM
	 Encodes the ASN1 ENUMERATED type, it is otherwise identical to
	 INTEGER.

       OBJECT, OID
	 Encodes an ASN1 OBJECT IDENTIFIER, the value string can be a short
	 name, a long name or numerical format.

       UTCTIME, UTC
	 Encodes an ASN1 UTCTime structure, the value should be in the format
	 YYMMDDHHMMSSZ.

       GENERALIZEDTIME, GENTIME
	 Encodes an ASN1 GeneralizedTime structure, the value should be in the
	 format YYYYMMDDHHMMSSZ.

       OCTETSTRING, OCT
	 Encodes an ASN1 OCTET STRING. value represents the contents of this
	 structure, the format strings ASCII and HEX can be used to specify
	 the format of value.

       BITSTRING, BITSTR
	 Encodes an ASN1 BIT STRING. value represents the contents of this
	 structure, the format strings ASCII, HEX and BITLIST can be used to
	 specify the format of value.

	 If the format is anything other than BITLIST the number of unused
	 bits is set to zero.

       UNIVERSALSTRING, UNIV, IA5, IA5STRING, UTF8, UTF8String, BMP,
       BMPSTRING, VISIBLESTRING, VISIBLE, PRINTABLESTRING, PRINTABLE, T61,
       T61STRING, TELETEXSTRING, GeneralString, NUMERICSTRING, NUMERIC
	 These encode the corresponding string types. value represents the
	 contents of this structure. The format can be ASCII or UTF8.

       SEQUENCE, SEQ, SET
	 Formats the result as an ASN1 SEQUENCE or SET type. value should be a
	 section name which will contain the contents. The field names in the
	 section are ignored and the values are in the generated string
	 format. If value is absent then an empty SEQUENCE will be encoded.

   MODIFIERS
       Modifiers affect the following structure, they can be used to add
       EXPLICIT or IMPLICIT tagging, add wrappers or to change the string
       format of the final type and value. The supported formats are
       documented below.

       EXPLICIT, EXP
	 Add an explicit tag to the following structure. This string should be
	 followed by a colon and the tag value to use as a decimal value.

	 By following the number with U, A, P or C UNIVERSAL, APPLICATION,
	 PRIVATE or CONTEXT SPECIFIC tagging can be used, the default is
	 CONTEXT SPECIFIC.

       IMPLICIT, IMP
	 This is the same as EXPLICIT except IMPLICIT tagging is used instead.

       OCTWRAP, SEQWRAP, SETWRAP, BITWRAP
	 The following structure is surrounded by an OCTET STRING, a SEQUENCE,
	 a SET or a BIT STRING respectively. For a BIT STRING the number of
	 unused bits is set to zero.

       FORMAT
	 This specifies the format of the ultimate value. It should be
	 followed by a colon and one of the strings ASCII, UTF8, HEX or
	 BITLIST.

	 If no format specifier is included then ASCII is used. If UTF8 is
	 specified then the value string must be a valid UTF8 string. For HEX
	 the output must be a set of hex digits. BITLIST (which is only valid
	 for a BIT STRING) is a comma separated list of the indices of the set
	 bits, all other bits are zero.

EXAMPLES
       A simple IA5String:

	IA5STRING:Hello World

       An IA5String explicitly tagged:

	EXPLICIT:0,IA5STRING:Hello World

       An IA5String explicitly tagged using APPLICATION tagging:

	EXPLICIT:0A,IA5STRING:Hello World

       A BITSTRING with bits 1 and 5 set and all others zero:

	FORMAT:BITLIST,BITSTRING:1,5

       A more complex example using a config file to produce a SEQUENCE
       consiting of a BOOL an OID and a UTF8String:

	asn1 = SEQUENCE:seq_section

	[seq_section]

	field1 = BOOLEAN:TRUE
	field2 = OID:commonName
	field3 = UTF8:Third field

       This example produces an RSAPrivateKey structure, this is the key
       contained in the file client.pem in all OpenSSL distributions (note:
       the field names such as 'coeff' are ignored and are present just for
       clarity):

	asn1=SEQUENCE:private_key
	[private_key]
	version=INTEGER:0

	n=INTEGER:0xBB6FE79432CC6EA2D8F970675A5A87BFBE1AFF0BE63E879F2AFFB93644\
	D4D2C6D000430DEC66ABF47829E74B8C5108623A1C0EE8BE217B3AD8D36D5EB4FCA1D9

	e=INTEGER:0x010001

	d=INTEGER:0x6F05EAD2F27FFAEC84BEC360C4B928FD5F3A9865D0FCAAD291E2A52F4A\
	F810DC6373278C006A0ABBA27DC8C63BF97F7E666E27C5284D7D3B1FFFE16B7A87B51D

	p=INTEGER:0xF3929B9435608F8A22C208D86795271D54EBDFB09DDEF539AB083DA912\
	D4BD57

	q=INTEGER:0xC50016F89DFF2561347ED1186A46E150E28BF2D0F539A1594BBD7FE467\
	46EC4F

	exp1=INTEGER:0x9E7D4326C924AFC1DEA40B45650134966D6F9DFA3A7F9D698CD4ABEA\
	9C0A39B9

	exp2=INTEGER:0xBA84003BB95355AFB7C50DF140C60513D0BA51D637272E355E397779\
	E7B2458F

	coeff=INTEGER:0x30B9E4F2AFA5AC679F920FC83F1F2DF1BAF1779CF989447FABC2F5\
	628657053A

       This example is the corresponding public key in a SubjectPublicKeyInfo
       structure:

	# Start with a SEQUENCE
	asn1=SEQUENCE:pubkeyinfo

	# pubkeyinfo contains an algorithm identifier and the public key wrapped
	# in a BIT STRING
	[pubkeyinfo]
	algorithm=SEQUENCE:rsa_alg
	pubkey=BITWRAP,SEQUENCE:rsapubkey

	# algorithm ID for RSA is just an OID and a NULL
	[rsa_alg]
	algorithm=OID:rsaEncryption
	parameter=NULL

	# Actual public key: modulus and exponent
	[rsapubkey]
	n=INTEGER:0xBB6FE79432CC6EA2D8F970675A5A87BFBE1AFF0BE63E879F2AFFB93644\
	D4D2C6D000430DEC66ABF47829E74B8C5108623A1C0EE8BE217B3AD8D36D5EB4FCA1D9

	e=INTEGER:0x010001

RETURN VALUES
       ASN1_generate_nconf() and ASN1_generate_v3() return the encoded data as
       an ASN1_TYPE structure or NULL if an error occurred.

       The error codes that can be obtained by ERR_get_error(3).

SEE ALSO
       ERR_get_error(3)

HISTORY
       ASN1_generate_nconf() and ASN1_generate_v3() were added to OpenSSL
       0.9.8



1.0.2k				  2017-01-26		ASN1_generate_nconf(3)