X509_NAME_get_index_by_NID, X509_NAME_get_index_by_OBJ, X509_NAME_get_entry,
X509_NAME_entry_count, X509_NAME_get_text_by_NID, X509_NAME_get_text_by_OBJ -
X509_NAME lookup and enumeration functions
#include <openssl/x509.h>
int X509_NAME_get_index_by_NID(const X509_NAME *name, int nid, int lastpos);
int X509_NAME_get_index_by_OBJ(const X509_NAME *name,
const ASN1_OBJECT *obj, int lastpos);
int X509_NAME_entry_count(const X509_NAME *name);
X509_NAME_ENTRY *X509_NAME_get_entry(const X509_NAME *name, int loc);
int X509_NAME_get_text_by_NID(const X509_NAME *name, int nid,
char *buf, int len);
int X509_NAME_get_text_by_OBJ(const X509_NAME *name, const ASN1_OBJECT *obj,
char *buf, int len);
These functions allow an
X509_NAME structure to be examined. The
X509_NAME structure is the same as the
Name type defined in
RFC2459 (and elsewhere) and used for example in certificate subject and issuer
names.
X509_NAME_get_index_by_NID() and
X509_NAME_get_index_by_OBJ()
retrieve the next index matching
nid or
obj after
lastpos.
lastpos should initially be set to -1. If there are no
more entries -1 is returned. If
nid is invalid (doesn't correspond to a
valid OID) then -2 is returned.
X509_NAME_entry_count() returns the total number of entries in
name.
X509_NAME_get_entry() retrieves the
X509_NAME_ENTRY from
name corresponding to index
loc. Acceptable values for
loc run from 0 to (
X509_NAME_entry_count(name) - 1). The value returned
is an internal pointer which must not be freed.
X509_NAME_get_text_by_NID(),
X509_NAME_get_text_by_OBJ() retrieve
the "text" from the first entry in
name which matches
nid or
obj, if no such entry exists -1 is returned. At most
len bytes will be written and the text written to
buf will be
null terminated. The length of the output string written is returned excluding
the terminating null. If
buf is <NULL> then the amount of space
needed in
buf (excluding the final null) is returned.
X509_NAME_get_text_by_NID() and
X509_NAME_get_text_by_OBJ() should
be considered deprecated because they have various limitations which make them
of minimal use in practice. They can only find the first matching entry and
will copy the contents of the field verbatim: this can be highly confusing if
the target is a multicharacter string type like a BMPString or a UTF8String.
For a more general solution
X509_NAME_get_index_by_NID() or
X509_NAME_get_index_by_OBJ() should be used followed by
X509_NAME_get_entry() on any matching indices and then the various
X509_NAME_ENTRY utility functions on the result.
The list of all relevant
NID_* and
OBJ_* codes can be found in the
source code header files
<openssl/obj_mac.h> and/or
<openssl/objects.h>.
Applications which could pass invalid NIDs to
X509_NAME_get_index_by_NID() should check for the return value of -2.
Alternatively the NID validity can be determined first by checking
OBJ_nid2obj(nid) is not NULL.
X509_NAME_get_index_by_NID() and
X509_NAME_get_index_by_OBJ()
return the index of the next matching entry or -1 if not found.
X509_NAME_get_index_by_NID() can also return -2 if the supplied NID is
invalid.
X509_NAME_entry_count() returns the total number of entries, and 0 for
failure.
X509_NAME_get_entry() returns an
X509_NAME pointer to the
requested entry or
NULL if the index is invalid.
Process all entries:
int i;
X509_NAME_ENTRY *e;
for (i = 0; i < X509_NAME_entry_count(nm); i++) {
e = X509_NAME_get_entry(nm, i);
/* Do something with e */
}
Process all commonName entries:
int lastpos = -1;
X509_NAME_ENTRY *e;
for (;;) {
lastpos = X509_NAME_get_index_by_NID(nm, NID_commonName, lastpos);
if (lastpos == -1)
break;
e = X509_NAME_get_entry(nm, lastpos);
/* Do something with e */
}
ERR_get_error(3),
d2i_X509_NAME(3)
Copyright 2002-2021 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (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>.