I have setup my LDAP server with user details. I have setup my Ubuntu laptop to authenticate users from LDAP. The problem is, every time user tries to log in, Ubuntu tries to reach LDAP servers to authenticate. So when network connection is out, it shows authentication failed. What I want is when user logs in first time, Ubuntu authenticates from LDAP, and creates a local user profile, and stores credential somewhere on local. So when network connection is not available, it authenticates against last used credentials. And when system connects back to internet, it authenticates against LDAP.
Please help me with this. Let me know if any clarifications are required.
I have created LDAP Server, and my ubuntu system is already authenticating users against LDAP. I want to store the LDAP credentials to a local user once the user logs in for the first time, so that these credentials can be used for authentication when network connection unavailable.
If you are using SSSD as the LDAP client, enable its built-in credential caching. Take a look at options cache_credentials (for auth) and cache_first (for account information) in the sssd.conf(5) manual page.
If you are using nslcd as the LDAP client, install pam_ccreds for authentication caching and nscd for account information caching.
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I'm running OpenVPN on a Centos 8 server and have it configured to use PAM authentication for users stored in an IPA server. The users are configured to require 2FA. Everything has been working as expected for several months. But recently our domain cert expired. After inserting the new cert into IPA, PAM authentication stopped working on the OpenVPN server.
Nothing in the logs pointed to anything conclusive so I assumed the IPA client running on the OpenVPN server may not be recognizing the new domain certs on the IPA server. So I uninstalled the IPA client on the OpenVPN server and then reinstalled it. Next I restarted the OpenVPN service, reconfigured sssd.conf and restarted sssd. I was now able to successfully authenticate as expected using a password + OTP token when initiating an OpenVPN connection.
But after rebooting the OpenVPN server, the PAM authentication is no longer requiring the 2FA token -- i.e. I can only initiate an OpenVPN connection with a password that does not include OTP token even though the user is configured to require 2FA. I repeated the same uninstall/reinstall steps and again password + 2FA token authentication worked as expected. But like before after reboot, the 2FA token authentication did not work.
After initially reinstalling the IPA ClientThe sssd log for sss_pam_preauth shows:
[pam] [pam_eval_prompting_config] (0x4000): Authentication types for
user [test55#ipa.mydomain.biz] and service [su]: password
two-factor
But after rebooting the sssd log for sss_pam_preauth shows:
[pam] [pam_eval_prompting_config] (0x4000): Authentication types for
user [test55#ipa.mydomain.biz] and service [su]: password
The sssd and pam config files are the same before and after reboot.
I'm at a loss to understand this behavior.
In my haste to repair the OpenVPN server I overlooked the sssd cache. The account I was using for testing at one time was not configured for 2FA.
It appears after reinstalling the IPA Client, authentication looked to the IPA server for sss_pam_preauth where the user is configured for 2FA. But after reboot sss_pam_preauth looked to the sssd cache where the user was not configured for 2FA.
So following the reboot I cleared the user from the sssd cache using the command sss_cache -u user1. With my next test, sss_pam_preauth could no longer find the user in the sssd cache and therefore looked to the IPA server which responded with a requirement for password + 2FA token as expected. I then rebooted the OpenVPN server again and sss_pam_preauth looked to the sssd cache where the user is now configured for 2FA.
The OpenVPN server is now working as expected.
I have problem integrating jFrog Artifactory with an Azure LDAPS.
Azure side is successfully configure, I get response by telnet on port 636.
Logs in the artifactory show this error:
Error connecting to the LDAP server:
org.springframework.security.authentication.AuthenticationServiceException:
User name.surname#bi****.de failed to authenticate
I understand that this error points to my user. But credentials for this user are 100% correct since I have enabled Azure Active Directory Services with user, enabled LDAPS and so on.
Can anyone specified in more detail what I was doing wrong on this picture below?
LDAP Integration screen
The search filter is incorrect, but the correct value will depend on what the users will log on with. If it's their AD username, you would use "sAMAccountName={0}" but the test ID you are using appears to be an e-mail address. To authenticate with your primary e-mail address, use "mail={0}" as the search filter.
Most likely "manager DN" / "manager password" needs a value as well. When you attempt to authenticate, the server connects to the LDAP service and binds with the "manager" account. It then searches for mail= and retrieves the fully qualified DN (FQDN) of the located object. The user supplied password is then validated by attempting to bind with the retrieved FQDN and user supplied password. If anonymous users have read access to the directory, you wouldn't need a manager dn/password. Anonymous read access is atypical for AD/Azure AD.
I use a "service" (i.e. non-user) account for my manager account -- using an actual user's account means someone has to come back and change the config every time the user updates their password. I set a long/complex password on service accounts and increase the password expiry time-frame so admins aren't re-configuring their applications monthly.
I have an ASP.NET MVC application that authenticates users against Active Directory.
As I understand this is the process happens when a user logs on to his computer:
User enters credentials on the local machine.
Local machine checks if it already has an authentication ticket for these credentials.
If not, it contacts the first ADS server it can find that offers kerberos authentication functions
The ADS machine checks the credentials against the LDAP database.
If they check out, kerberos returns a TGT (ticket-granting-ticket) to the client machine
For a certain duration set in AD (usually 8~10 hours) this TGT will bypass any credential checking in case the local machine user wishes to connect to resources that require permissions not present in his bare user account (i.e. group memberships, additional machine and share access, etc.)
My question is how does IIS know about the TGT when the browser is making a request to it for my app? Does the operating system send it out on every outbound http request to every single website?
The server (IIS) will indicate to the client (browser) that it needs to authenticate by returning an HTTP 401 error code with a WWW-Authenticate header. The client detects this and determines if it can correctly authenticate. The way this works is as follows:
Determine who the requestor is by checking it's Service Principal Name. It exists as {type}/{fully.qualified.domain}, e.g. HTTP/resource.domain.com. This SPN is mapped to a machine or service account in AD. If this SPN isn't registered, the client falls back to a lesser protocol like NTLM.
Local machine uses the TGT to request a service ticket from AD. AD validates the TGT and looks up the SPN in the request and if found creates a service ticket encrypted against the password of the account associated to the SPN.
Client sends the service ticket to the server via Authorization: Negotiate YII... header.
Server decrypts the service ticket using the password it's been provided, either through a domain join, Windows Service Run As config, or keytab.
Server transforms the contents of the decrypted service ticket into a Windows identity.
Identity is presented to the application.
This flow isn't inherently web-specific. This is how all services authenticate themselves when using Kerberos.
Problem: I want users from my corporate client to authenticate with my web server by using their local LDAP credentials. Users have a local desktop client that can authenticate with the local LDAP server. My server and the LDAP server do not talk to each other.
I know it is possible to authenticate on a web server using LDAP if the web server relays the LDAP request to a LDAP server. (User/desktop client connects to web server, sends credentials and web server interacts with LDAP server for authentication)
But is there a way for a desktop client to authenticate with a local LDAP server and then connect to a web server sending a token that would grant access to the web server? (user auths with ldap, sends ldap response to webserver)
I am not talking Oauth, which requires both servers to talk. In this case, the LDAP server is isolated from outside contact.
The big problem here is that you should never trust the client, even if you have written it yourself. Something like public/private authentication would (probably) not work as well, since the problem is not the encryption, but making sure the message came as "OK" from the LDAP server. A rogue client could fake the OK and sign it anyway.
If I understand your problem correctly, you're looking for a way to make your desktop client talk to your web application using the user's domain credentials.
This should be easy to do using something like ADFS. If you run ADFS inside your clients Active Directory domain, your desktop client can get a token from it using Kerberos. It can then use this token to authenticate with your web application.
You will need to configure your web application to trust tokens issued by the ADFS instance in your clients domain.
ADFS may work, but it is unnecessary. You should look into using SPNEGO as it does not require a ADFS infrastructure.
My understanding is that both JAAS and SQL Server can be configured to use kerberos in a domain environment, with an active directory server.
My understanding that JAAS gets the user credentials from the user or from a file at the time of the connection - asks the directory server for a ticket, and presents that to the server.
Where does the SQL Server Driver get its kerberos ticket from? (as it seems to be able to obtain creditentials from the users existing login). Does it get the user login ticket - or does it extract the credentials from the user's logged in session?
SQL Server Driver gets Kerberos tickets from TGT (ticket granting ticket). This TGT is a ticket that is part of user's logon session and can be used to get short lived tickets to authenticate to other services (E.g. SQL Server).
You can use "Kerbtrey" utility from Windows Server Resource kit to examine such tickets.
JAAS also uses the same tickets but it needs to be told to obtain tickets + configuration (E.g. name of Kerberos server) from file and that path is somewhat dependent on OS version.
SQL Server drivers uses Wind32 API to get tokens.