X509_NAME_PRINT_EX(3)

NAME
X509_NAME_print_ex, X509_NAME_print_ex_fp, X509_NAME_oneline - X509_NAME printing routines

SYNOPSIS
libcrypto
#include <openssl/x509.h>
int
X509_NAME_print_ex(BIO *out, const X509_NAME *nm, int indent, unsigned long flags);
int
X509_NAME_print_ex_fp(FILE *fp, const X509_NAME *nm, int indent, unsigned long flags);
char *
X509_NAME_oneline(const X509_NAME *a, char *buf, int size);

DESCRIPTION
X509_NAME_print_ex() prints a human readable version of nm to BIO out. Each line (for multiline formats) is indented by indent spaces. The output format can be extensively customised by use of the flags parameter.

X509_NAME_print_ex_fp() is identical to X509_NAME_print_ex() except the output is written to the FILE pointer fp.

X509_NAME_oneline() prints an ASCII version of a to buf. If buf is NULL, then a buffer is dynamically allocated and returned, and size is ignored. Otherwise, at most size bytes will be written, including the ending NUL, and buf is returned.

X509_NAME_oneline() is a legacy function which produces a non-standard output form. It doesn't handle multi-character fields and has various quirks and inconsistencies. Its use is strongly discouraged in new applications.

Although there are a large number of possible flags, for most purposes XN_FLAG_ONELINE, XN_FLAG_MULTILINE, or XN_FLAG_RFC2253 will suffice. As noted on the ASN1_STRING_print_ex(3) manual page, for UTF-8 terminals the ASN1_STRFLGS_ESC_MSB should be unset: so for example XN_FLAG_ONELINE & ~ASN1_STRFLGS_ESC_MSB would be used.

The complete set of the flags supported by X509_NAME_print_ex is listed below.

Several options can be OR'ed together.

The options XN_FLAG_SEP_COMMA_PLUS, XN_FLAG_SEP_CPLUS_SPC, XN_FLAG_SEP_SPLUS_SPC, and XN_FLAG_SEP_MULTILINE determine the field separators to use. Two distinct separators are used between distinct RelativeDistinguishedName components and separate values in the same RDN for a multi-valued RDN. Multi-valued RDNs are currently very rare so the second separator will hardly ever be used.

XN_FLAG_SEP_COMMA_PLUS uses comma and plus as separators. XN_FLAG_SEP_CPLUS_SPC uses comma and plus with spaces: this is more readable that plain comma and plus. XN_FLAG_SEP_SPLUS_SPC uses spaced semicolon and plus. XN_FLAG_SEP_MULTILINE uses spaced newline and plus respectively. XN_FLAG_SEP_MASK contains the bits used to represent these four options.

If XN_FLAG_DN_REV is set, the whole DN is printed in reversed order.

The fields XN_FLAG_FN_SN, XN_FLAG_FN_LN, XN_FLAG_FN_OID, and XN_FLAG_FN_NONE determine how a field name is displayed. It will use the short name (e.g. CN), the long name (e.g. commonName), always use OID numerical form (normally OIDs are only used if the field name is not recognised) and no field name, respectively. XN_FLAG_FN_MASK contains the bits used to represent these four options.

If XN_FLAG_SPC_EQ is set, then spaces will be placed around the ‘=’ character separating field names and values.

If XN_FLAG_DUMP_UNKNOWN_FIELDS is set, then the encoding of unknown fields is printed instead of the values.

If XN_FLAG_FN_ALIGN is set, then field names are padded to 20 characters: this is only of use for multiline format.

Additionally, all the options supported by ASN1_STRING_print_ex(3) can be used to control how each field value is displayed.

In addition a number of options can be set for commonly used formats.

XN_FLAG_RFC2253 sets options which produce an output compatible with RFC 2253. It is equivalent to ASN1_STRFLGS_RFC2253 | XN_FLAG_SEP_COMMA_PLUS | XN_FLAG_DN_REV | XN_FLAG_FN_SN | XN_FLAG_DUMP_UNKNOWN_FIELDS.

XN_FLAG_ONELINE is a more readable one line format which is the same as: ASN1_STRFLGS_RFC2253 | ASN1_STRFLGS_ESC_QUOTE | XN_FLAG_SEP_CPLUS_SPC | XN_FLAG_SPC_EQ | XN_FLAG_FN_SN.

XN_FLAG_MULTILINE is a multiline format which is the same as: ASN1_STRFLGS_ESC_CTRL | ASN1_STRFLGS_ESC_MSB | XN_FLAG_SEP_MULTILINE | XN_FLAG_SPC_EQ | XN_FLAG_FN_LN | XN_FLAG_FN_ALIGN.

XN_FLAG_COMPAT uses the traditional non-standard SSLeay format.

RETURN VALUES
X509_NAME_print_ex() and X509_NAME_print_ex_fp() return 1 on success or 0 on error if XN_FLAG_COMPAT is set in flags. Otherwise, they return the number of printed bytes including the indentation or -1 on error.

X509_NAME_oneline() returns a valid string on success or NULL on error.

SEE ALSO
ASN1_STRING_print_ex(3), d2i_X509_NAME(3), X509_NAME_get_index_by_NID(3), X509_NAME_new(3)

HISTORY
X509_NAME_oneline() first appeared in SSLeay 0.5.1 and has been available since OpenBSD 2.4.

X509_NAME_print_ex() and X509_NAME_print_ex_fp() first appeared in OpenSSL 0.9.6 and have been available since OpenBSD 2.9.