ASN1_STRING_print_ex(3SSL) OpenSSL ASN1_STRING_print_ex(3SSL)
NAME
ASN1_STRING_print_ex, ASN1_STRING_print_ex_fp - ASN1_STRING output rou-
tines.
SYNOPSIS
#include <openssl/asn1.h>
int ASN1_STRING_print_ex(BIO *out, ASN1_STRING *str, unsigned long flags);
int ASN1_STRING_print_ex_fp(FILE *fp, ASN1_STRING *str, unsigned long flags);
int ASN1_STRING_print(BIO *out, ASN1_STRING *str);
DESCRIPTION
These functions output an ASN1_STRING structure. ASN1_STRING is used to
represent all the ASN1 string types.
ASN1_STRING_print_ex() outputs str to out, the format is determined by
the options flags. ASN1_STRING_print_ex_fp() is identical except it
outputs to fp instead.
ASN1_STRING_print() prints str to out but using a different format to
ASN1_STRING_print_ex(). It replaces unprintable characters (other than
CR, LF) with '.'.
NOTES
ASN1_STRING_print() is a legacy function which should be avoided in new
applications.
Although there are a large number of options frequently ASN1_STR-
FLGS_RFC2253 is suitable, or on UTF8 terminals ASN1_STRFLGS_RFC2253 &
~ASN1_STRFLGS_ESC_MSB.
The complete set of supported options for flags is listed below.
Various characters can be escaped. If ASN1_STRFLGS_ESC_2253 is set the
characters determined by RFC2253 are escaped. If ASN1_STRFLGS_ESC_CTRL
is set control characters are escaped. If ASN1_STRFLGS_ESC_MSB is set
characters with the MSB set are escaped: this option should not be used
if the terminal correctly interprets UTF8 sequences.
Escaping takes several forms.
If the character being escaped is a 16 bit character then the form
"\WXXXX" is used using exactly four characters for the hex representa-
tion. If it is 32 bits then "\UXXXXXXXX" is used using eight characters
of its hex representation. These forms will only be used if UTF8 con-
version is not set (see below).
Printable characters are normally escaped using the backslash '\' char-
acter. If ASN1_STRFLGS_ESC_QUOTE is set then the whole string is
instead surrounded by double quote characters: this is arguably more
readable than the backslash notation. Other characters use the "\XX"
using exactly two characters of the hex representation.
If ASN1_STRFLGS_UTF8_CONVERT is set then characters are converted to
UTF8 format first. If the terminal supports the display of UTF8
sequences then this option will correctly display multi byte charac-
ters.
If ASN1_STRFLGS_IGNORE_TYPE is set then the string type is not inter-
preted at all: everything is assumed to be one byte per character. This
is primarily for debugging purposes and can result in confusing output
in multi character strings.
If ASN1_STRFLGS_SHOW_TYPE is set then the string type itself is printed
out before its value (for example "BMPSTRING"), this actually uses
ASN1_tag2str().
The content of a string instead of being interpreted can be "dumped":
this just outputs the value of the string using the form #XXXX using
hex format for each octet.
If ASN1_STRFLGS_DUMP_ALL is set then any type is dumped.
Normally non character string types (such as OCTET STRING) are assumed
to be one byte per character, if ASN1_STRFLGS_DUMP_UNKNOWN is set then
they will be dumped instead.
When a type is dumped normally just the content octets are printed, if
ASN1_STRFLGS_DUMP_DER is set then the complete encoding is dumped
instead (including tag and length octets).
ASN1_STRFLGS_RFC2253 includes all the flags required by RFC2253. It is
equivalent to:
ASN1_STRFLGS_ESC_2253 | ASN1_STRFLGS_ESC_CTRL | ASN1_STRFLGS_ESC_MSB |
ASN1_STRFLGS_UTF8_CONVERT | ASN1_STRFLGS_DUMP_UNKNOWN ASN1_STR-
FLGS_DUMP_DER
SEE ALSO
X509_NAME_print_ex(3), ASN1_tag2str(3)
HISTORY
TBA
0.9.8c 2004-11-13 ASN1_STRING_print_ex(3SSL)
