Updated: 2021/Apr/14


ASN1_STRING_length(3)               OpenSSL              ASN1_STRING_length(3)



NAME
       ASN1_STRING_dup, ASN1_STRING_cmp, ASN1_STRING_set, ASN1_STRING_length,
       ASN1_STRING_type, ASN1_STRING_get0_data, ASN1_STRING_data,
       ASN1_STRING_to_UTF8 - ASN1_STRING utility functions

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/asn1.h>

        int ASN1_STRING_length(ASN1_STRING *x);
        const unsigned char * ASN1_STRING_get0_data(const ASN1_STRING *x);
        unsigned char * ASN1_STRING_data(ASN1_STRING *x);

        ASN1_STRING * ASN1_STRING_dup(ASN1_STRING *a);

        int ASN1_STRING_cmp(ASN1_STRING *a, ASN1_STRING *b);

        int ASN1_STRING_set(ASN1_STRING *str, const void *data, int len);

        int ASN1_STRING_type(const ASN1_STRING *x);

        int ASN1_STRING_to_UTF8(unsigned char **out, const ASN1_STRING *in);

DESCRIPTION
       These functions allow an ASN1_STRING structure to be manipulated.

       ASN1_STRING_length() returns the length of the content of x.

       ASN1_STRING_get0_data() returns an internal pointer to the data of x.
       Since this is an internal pointer it should not be freed or modified in
       any way.

       ASN1_STRING_data() is similar to ASN1_STRING_get0_data() except the
       returned value is not constant. This function is deprecated:
       applications should use ASN1_STRING_get0_data() instead.

       ASN1_STRING_dup() returns a copy of the structure a.

       ASN1_STRING_cmp() compares a and b returning 0 if the two are
       identical. The string types and content are compared.

       ASN1_STRING_set() sets the data of string str to the buffer data or
       length len. The supplied data is copied. If len is -1 then the length
       is determined by strlen(data).

       ASN1_STRING_type() returns the type of x, using standard constants such
       as V_ASN1_OCTET_STRING.

       ASN1_STRING_to_UTF8() converts the string in to UTF8 format, the
       converted data is allocated in a buffer in *out. The length of out is
       returned or a negative error code. The buffer *out should be freed
       using OPENSSL_free().

NOTES
       Almost all ASN1 types in OpenSSL are represented as an ASN1_STRING
       structure. Other types such as ASN1_OCTET_STRING are simply typedef'ed
       to ASN1_STRING and the functions call the ASN1_STRING equivalents.
       ASN1_STRING is also used for some CHOICE types which consist entirely
       of primitive string types such as DirectoryString and Time.

       These functions should not be used to examine or modify ASN1_INTEGER or
       ASN1_ENUMERATED types: the relevant INTEGER or ENUMERATED utility
       functions should be used instead.

       In general it cannot be assumed that the data returned by
       ASN1_STRING_data() is null terminated or does not contain embedded
       nulls. The actual format of the data will depend on the actual string
       type itself: for example for an IA5String the data will be ASCII, for a
       BMPString two bytes per character in big endian format, and for a
       UTF8String it will be in UTF8 format.

       Similar care should be take to ensure the data is in the correct format
       when calling ASN1_STRING_set().

RETURN VALUES
       ASN1_STRING_length() returns the length of the content of x.

       ASN1_STRING_get0_data() and ASN1_STRING_data() return an internal
       pointer to the data of x.

       ASN1_STRING_dup() returns a valid ASN1_STRING structure or NULL if an
       error occurred.

       ASN1_STRING_cmp() returns an integer greater than, equal to, or less
       than 0, according to whether a is greater than, equal to, or less than
       b.

       ASN1_STRING_set() returns 1 on success or 0 on error.

       ASN1_STRING_type() returns the type of x.

       ASN1_STRING_to_UTF8() returns the number of bytes in output string out
       or a negative value if an error occurred.

SEE ALSO
       ERR_get_error(3)

COPYRIGHT
       Copyright 2002-2020 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.



1.1.1i                            2020-12-10             ASN1_STRING_length(3)