Blank Password for a ldap user

["Rocky S" <rak6970@gmail.com>]

I am very new ldap programming, so bear with me if my query is naive.

I am trying to write a program using the OpenLDAP SDK.
The program should take an LDAP servername/port, a CN & a password.
The program should then report if the CN/password combination is correct
or incorrect.

This is how I am trying to do this.
[ error checks removed for making it simple]

LDAP *pldap;
ldap_initialize(&pldap, "ldap://myhost:389) ;

int desired_version = LDAP_VERSION3;
ldap_set_option(pldap, LDAP_OPT_PROTOCOL_VERSION, &desired_version);

int ret = ldap_bind_s(pldap,
"uid=Jack,ou=People,dc=vss,dc=veritas,dc=com", "jack123",
LDAP_AUTH_SIMPLE);

if(ret == LDAP_SUCCESS)
  puts("VERIFIED");
else
  puts("FAILURE");

This works fine for for Jack/jack123.

I have another user in the directory - John who has a null/empty password

I tried both
ldap_bind_s(pldap, "uid=John,ou=People,dc=vss,dc=veritas,dc=com",
NULL, LDAP_AUTH_SIMPLE);

ldap_bind_s(pldap, "uid=John,ou=People,dc=vss,dc=veritas,dc=com", "",
LDAP_AUTH_SIMPLE);

Both cases ldap_bind_s returns 53 - which I think means LDAP UNWILLING
TO PERFORM


I know the server allows null passwords.