int ASN1_STRING_length(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(ASN1_STRING *x);
int ASN1_STRING_to_UTF8(unsigned char **out, 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_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_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 free 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
typedefed 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 and IA5String the data will be ASCII,
for a BMPString two bytes per character in big endian format,
UTF8String will be in UTF8 format.
Similar care should be take to ensure the data is in the correct
format when calling ASN1_STRING_set().
