/usr/man/cat.3/ASN1_generate_v3.3

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.

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     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.

BMPSTRING, VISIBLESTRING, VISIBLE, PRINTABLESTRING, PRINTABLE,

T61, T61STRING, TELETEXSTRING, GeneralString, NUMERICSTRING,

NUMERIC

     UNIVERSALSTRING, UNIV, IA5, IA5STRING, UTF8, UTF8String, BMP,
       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

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ASN1_generate_nconf(3)       OpenSSL       ASN1_generate_nconf(3)

       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

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ASN1_generate_nconf(3)       OpenSSL       ASN1_generate_nconf(3)

      [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

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ASN1_generate_nconf(3)       OpenSSL       ASN1_generate_nconf(3)

      # 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

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See also ASN1_generate_nconf(3)