Hi Piotr

I agree with that. But I would like to know, what's the purpose of those two
keys with respect to SSLVPN.

With regards
Kings


On Tue, Sep 6, 2011 at 5:16 PM, Piotr Matusiak <[email protected]> wrote:

> Kings,
>
> The ASA generates keys on behalf of the user and issue a certificate which
> is transferred during enrollment process to the client with PKCS12
> (keys+cert) format. That's why there are two keys.
>
>
> Regards,
> Piotr
>
>
>
> 2011/9/6 Kingsley Charles <[email protected]>
>
>> I did some investigation and based upon the debugs and documentation, the
>> following is how the authentication happens for SSLVPN with clients.
>>
>> 1)The user is added to the ASA CA Server user db and an OTP is generated.
>> 2)The user https://IP 
>> address/+CSCOCA+/enroll.html<https://asa2/+CSCOCA+/enroll.html>and enters 
>> the username/OTP.
>> 3)The user downloads the certificate.
>> 4)The user now logins into the SSLVPN portal and sends the certificate for
>> authentication.
>> 5)The ASA uses the Local CA server trustpoint to validate the signature.
>> The downloaded/sent certificate signature is signed by the CA Server's
>> private key. When  the ASA gets the certificate from the user for sslvpn
>> authenticate, it generates the hash of the certificate. The signature from
>> the certificate is decrypted using the CA Server public key and now both
>> hash are compared. If they are same, then authentication passes.
>>
>> If I am missing something, please let me know.
>>
>>
>> Now, one question is still not answered for me.
>>
>> Why does the ASA CA server put a public and private key in the user's
>> certificate? What is the purpose of those keys?
>>
>>
>> With regards
>> Kings
>>
>>
>> On Tue, Sep 6, 2011 at 1:27 PM, Kingsley Charles <
>> [email protected]> wrote:
>>
>>> HI Piotr
>>>
>>> As you said, the ASA CA Server is meant only for it's sslvpn user
>>> authentication
>>>
>>> Snippet from
>>> http://www.cisco.com/en/US/docs/security/asa/asa80/configuration/guide/cert_cfg.html#wp1067484
>>> The Local CA
>>>
>>> The Local Certificate Authority (Local CA) performs the following tasks:
>>>
>>> •Integrates basic certificate authority functionality on the security
>>> appliance.
>>>
>>> •Deploys certificates.
>>>
>>> •Provides secure revocation checking of issued certificates.
>>>
>>> •Provides a certificate authority on the adaptive security appliance for
>>> use with SSL VPN connections, both browser- and client-based.
>>>
>>> •Provides trusted digital certificates to users, without the need to rely
>>> on external certificate authorization.
>>>
>>> •Provides a secure in-house authority for certificate authentication and
>>> offers straightforward user enrollment by means of a browser web page login.
>>>
>>>
>>>
>>> With regards
>>> Kings
>>>
>>>
>>> On Tue, Sep 6, 2011 at 1:11 PM, Kingsley Charles <
>>> [email protected]> wrote:
>>>
>>>> Hi Piotr
>>>>
>>>> I just checked a downloaded certificate's usage from the ASA CA Server
>>>> and it was signature type. Normally, the self signed certificates from
>>>> webservers will have usage type of encryption and the public key will be
>>>> used for encrypting the master key sent by the client to the server. The
>>>> client side doesn't need an encryption usage certificate and only requires 
>>>> a
>>>> certificate with signature usage.
>>>>
>>>> With EAP, client also would only require certificate usage type of
>>>> signature and hence, I think ASA CA server would be suffice.
>>>>
>>>> Just sharing my thought. Practically, I have not tried with EAP :-)
>>>>
>>>>
>>>> I have one more query
>>>>
>>>> The downloaded certificate from the ASA CA server has public key and
>>>> private key. Now, with ASA CA server we don't enroll by sending PKCS#10
>>>> which has the public key.
>>>>
>>>> Said with that, whose public and private key are present in the
>>>> downloaded certificate. Does the ASA CA server create and add keys for each
>>>> user?
>>>>
>>>> With regards
>>>> Kings
>>>>
>>>>
>>>> On Tue, Sep 6, 2011 at 12:58 PM, Piotr Matusiak <[email protected]> wrote:
>>>>
>>>>> Right, this is because ASA CA can only issue a certificate for SSL
>>>>> purposes. You cannot use them in EAP I believe.
>>>>>
>>>>>
>>>>> Regards,
>>>>> Piotr
>>>>>
>>>>>
>>>>> 2011/9/6 Kingsley Charles <[email protected]>
>>>>>
>>>>>> Piotr,
>>>>>>
>>>>>> Does it mean that the ASA CA server has been implemented as a
>>>>>> complementary for it's own webvpn feature? ASA CA server can be also 
>>>>>> used to
>>>>>> generate certificates for any users to authenticate with any other
>>>>>> applications other than ASA WebVPN, isn't it?
>>>>>>
>>>>>> We need some web service for CA Service. In IOS, we use http server
>>>>>> web service not webvpn.
>>>>>>
>>>>>> But in ASA, we don't use http service rather webvpn web service.
>>>>>>
>>>>>> Just wondering, why Cisco didn't use http server web service. If I
>>>>>> need a CA Server alone for issuing identity certificates, why would I 
>>>>>> need
>>>>>> to run WebVPN?
>>>>>>
>>>>>> For example, I need a certificate for EAP TLS or EAP FAST
>>>>>> authentication, I just need a CA Server not WebVPN.
>>>>>>
>>>>>> With regards
>>>>>> Kings
>>>>>>
>>>>>>
>>>>>> On Tue, Sep 6, 2011 at 12:32 PM, Piotr Matusiak <[email protected]>wrote:
>>>>>>
>>>>>>> What's the ASA CA purpose? To give out certificate for SSL
>>>>>>> (clientless and full client), right? In both cases you need webvpn to be
>>>>>>> enabled.
>>>>>>>
>>>>>>>
>>>>>>> Regards,
>>>>>>> Piotr
>>>>>>>
>>>>>>>
>>>>>>> 2011/9/6 Kingsley Charles <[email protected]>
>>>>>>>
>>>>>>>> Hi Piotr
>>>>>>>>
>>>>>>>> Great, that made it work.
>>>>>>>>
>>>>>>>> But why do we need webvpn to be enabled? Is CA server embedded with
>>>>>>>> WebVPN service?
>>>>>>>>
>>>>>>>> With regards
>>>>>>>> Kings
>>>>>>>>
>>>>>>>>
>>>>>>>> On Tue, Sep 6, 2011 at 11:33 AM, Piotr Matusiak <[email protected]>wrote:
>>>>>>>>
>>>>>>>>> Hi Kings,
>>>>>>>>>
>>>>>>>>> You need WebVPN to be enabled for that.
>>>>>>>>>
>>>>>>>>> Regards,
>>>>>>>>> Piotr
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> 2011/9/6 Kingsley Charles <[email protected]>
>>>>>>>>>
>>>>>>>>>> Hi Piotr
>>>>>>>>>>
>>>>>>>>>> I don't have webvpn configured? I get the same log message even
>>>>>>>>>> when I use IP address. Do we need http server enabled? I tried 
>>>>>>>>>> enabling http
>>>>>>>>>> server too and that didn't work for me.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> With regards
>>>>>>>>>> Kings
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On Mon, Sep 5, 2011 at 8:26 PM, Piotr Matusiak <[email protected]>wrote:
>>>>>>>>>>
>>>>>>>>>>> Hi Kings,
>>>>>>>>>>>
>>>>>>>>>>> Did you enable webvpn on the outside?
>>>>>>>>>>> You can connect using IP address as well.
>>>>>>>>>>>
>>>>>>>>>>> Regards,
>>>>>>>>>>> Piotr
>>>>>>>>>>>
>>>>>>>>>>> 2011/9/5 Kingsley Charles <[email protected]>
>>>>>>>>>>>
>>>>>>>>>>>> Hi all
>>>>>>>>>>>>
>>>>>>>>>>>> I have configured the ASA for CA server and when I try to access
>>>>>>>>>>>> the enrollment URL, I get the following logs: From the log 
>>>>>>>>>>>> reference for
>>>>>>>>>>>> 710005, I think,  the CA server service is not running.
>>>>>>>>>>>>
>>>>>>>>>>>> I am trying to access enrollment url using the host name
>>>>>>>>>>>> https://asa2/+CSCOCA+/enroll.html and have defined hostname to
>>>>>>>>>>>> IP address mapping in the host file. I remember, we can only 
>>>>>>>>>>>> access using
>>>>>>>>>>>> hostname not IP address.
>>>>>>>>>>>>
>>>>>>>>>>>> Any thoughts?
>>>>>>>>>>>>
>>>>>>>>>>>> *Config*
>>>>>>>>>>>>
>>>>>>>>>>>> crypto ca server
>>>>>>>>>>>>  subject-name-default cn=ca
>>>>>>>>>>>>  smtp from-address [email protected]
>>>>>>>>>>>>
>>>>>>>>>>>> *Logs*
>>>>>>>>>>>>
>>>>>>>>>>>> %ASA-7-710005: TCP request discarded from 10.20.30.40/1750 to
>>>>>>>>>>>> outside:10.20.30.43/443
>>>>>>>>>>>> %ASA-3-710003: TCP access denied by ACL from 10.20.30.40/1750to 
>>>>>>>>>>>> outside:
>>>>>>>>>>>> 10.20.30.43/443
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Snippet from
>>>>>>>>>>>> http://www.cisco.com/en/US/docs/security/asa/asa71/system/message/logmsgs.html#wp1285746
>>>>>>>>>>>>  710005
>>>>>>>>>>>>
>>>>>>>>>>>> Error Message    %PIX|ASA-7-710005: {TCP|UDP} request discarded 
>>>>>>>>>>>> from *source_address/source_port* to 
>>>>>>>>>>>> *interface_name:dest_address/service*
>>>>>>>>>>>>
>>>>>>>>>>>> Explanation    This message appears when the Cisco ASA does not
>>>>>>>>>>>> have a UDP server that services the UDP request. The message can 
>>>>>>>>>>>> also
>>>>>>>>>>>> indicate a TCP packet that does not belong to any session on the 
>>>>>>>>>>>> Cisco ASA .
>>>>>>>>>>>> In addition, this message appears (with the service *snmp*)
>>>>>>>>>>>> when the Cisco ASA receives an SNMP request with an empty payload, 
>>>>>>>>>>>> even if
>>>>>>>>>>>> it is from an authorized host. When the service is *snmp*, this
>>>>>>>>>>>> message occurs a maximum of 1 time every 10 seconds so that the 
>>>>>>>>>>>> log receiver
>>>>>>>>>>>> is not overwhelmed.
>>>>>>>>>>>>
>>>>>>>>>>>> Recommended Action    In networks that heavily utilize
>>>>>>>>>>>> broadcasting services such as DHCP, RIP or NetBios, the frequency 
>>>>>>>>>>>> of this
>>>>>>>>>>>> message can be high. If this message appears in excessive number, 
>>>>>>>>>>>> it may
>>>>>>>>>>>> indicate an attack.
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> With regards
>>>>>>>>>>>> Kings
>>>>>>>>>>>>
>>>>>>>>>>>> _______________________________________________
>>>>>>>>>>>> For more information regarding industry leading CCIE Lab
>>>>>>>>>>>> training, please visit www.ipexpert.com
>>>>>>>>>>>>
>>>>>>>>>>>> Are you a CCNP or CCIE and looking for a job? Check out
>>>>>>>>>>>> www.PlatinumPlacement.com
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>
_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

Are you a CCNP or CCIE and looking for a job? Check out 
www.PlatinumPlacement.com

Reply via email to