link ldap backend don't restrict access

[centredecalcul]

Step to reproduce

• configure ldap backend, restrict users access by ldap filter
• enable cas_link_to_ldap_backend

Expected result

• users who don't match LDAP filter will not have access to owncCloud

Actual result

• everyone who can connect to CAS can also use the cloud

Solution

• in user_cas.php,

if (($uid !== false) && ($ocname !== false)) {
    OC_Log::write('cas',"Found CAS user '$uid' in LDAP with name '$ocname'", OC_Log::DEBUG);
    return $ocname;
}

• by:

if (($uid !== false) && ($ocname !== false)) {
    OC_Log::write('cas',"Found CAS user '$uid' in LDAP with name '$ocname'", OC_Log::DEBUG);
    return $ocname;
} else {
    return false;
}

Because the function checkPassword return $uid at the end.