Re: Using Arbitrary X509 certificates for LDAPS authentication

[Stephen Cartwright <034710@gmail.com>]

Hi there,

I looked into this and I don't understand :( Would you please clarify
why a DN such as "/C=CA/O=Grid/CN=host/somehost.somedomain.ca" is
broken? You said "somehost.somedomain.ca" is not a valid RDN because
it just has a value and not a type, however the RDN is not just
"somehost.somedomain.ca" but "CN=host/somehost.somedomain.ca" which
has a type of "CN" and a value of "host/somehost.somedomain.ca" does
it not? If this RDN is in fact valid, I still don't understand why DNs
of the form
"/C=CA/O=Grid/CN=host/somehost.somedomain.ca" seem to not work with LDAP.

Thanks,

Stephen

On Wed, Sep 2, 2009 at 7:35 PM, Howard Chu <hyc@symas.com> wrote:
> Stephen Cartwright wrote:
>>
>> Hi there,
>>
>> Are there any restrictions on the DN or other attributes of
>> credentials used for LDAP authentication?
>>
>> We are using grid credentials (X509 format) with DNs like this:
>>
>> issuer= /C=CA/O=Grid/CN=Grid Canada Certificate Authority
>> subject= /C=CA/O=Grid/CN=host/somehost.somedomain.ca
>
> "somehost.somedomain.ca" is not a valid RDN. RDNs require both a type and a
> value, but here you have only a value. Whatever CA software you're using is
> broken if it's allowing you to create certificates like this.
>>
>> When I use some grid certs (X509 format)  I see this message in the debug
>> output from slapd:
>>
>> connection_read(10): unable to get TLS client DN error=49 id=3
>>
>> When I try to connect, I get this:
>>
>> ldap_initialize( ldaps://somehost.somedomain.ca )
>> ldap_bind: Can't contact LDAP server
>>
>> The openssl command to create a connection works OK:
>>
>> CONNECTED(00000003)
>> ---
>> Certificate chain
>>   0 s:/C=CA/O=Grid/CN=host/somehost.somedomain.ca
>>     i:/C=CA/O=Grid/CN=Grid Canada Certificate Authority
>>   1 s:/C=CA/O=Grid/CN=Grid Canada Certificate Authority
>>     i:/C=CA/O=Grid/CN=Grid Canada Certificate Authority
>> ---
>> Server certificate
>> -----BEGIN CERTIFICATE-----
>> ...
>> -----END CERTIFICATE-----
>> subject=/C=CA/O=Grid/CN=host/somehost.somedomain.ca
>> issuer=/C=CA/O=Grid/CN=Grid Canada Certificate Authority
>> ---
>> No client certificate CA names sent
>> ---
>> SSL handshake has read 2083 bytes and written 320 bytes
>> ---
>> New, TLSv1/SSLv3, Cipher is DES-CBC3-SHA
>> Server public key is 1024 bit
>> SSL-Session:
>>      Protocol  : TLSv1
>>      Cipher    : DES-CBC3-SHA
>>      Session-ID:
>> 43B46528E848663E7C8E9CAAEA4E6DB5E4A9675C05C3066DBD826CD1CF59A566
>>      Session-ID-ctx:
>>    Master-Key:
>>
>> A8245A0731BA98F0D88821346432868C392FEE3F23EAFB9F356A34CB6BB663FC0892374118F280D6284C8E2ACAC3
>>      Key-Arg   : None
>>      Start Time: 1251330160
>>      Timeout   : 300 (sec)
>>      Verify return code: 0 (ok)
>>
>> When I use certs created by us with another DN format such as this:
>>
>> subject=
>> /C=CA/ST=Province/L=Town/O=Organization/OU=Unit/CN=somehost.somedomain.ca/emailAddress=email@somewhere.ca
>> issuer= /C=CA/ST=Province/O=Organization/OU=Town/CN=Our
>> CA/emailAddress=email@somewhere.ca
>>
>> And then make no other changes to the config other than pointing
>> everything to the new commands I can make a connection.
>>
>> Any suggestions? Please advise.
>>
>> Steve
>>
>
>
> --
>  -- Howard Chu
>  CTO, Symas Corp.           http://www.symas.com
>  Director, Highland Sun     http://highlandsun.com/hyc/
>  Chief Architect, OpenLDAP  http://www.openldap.org/project/
>