The server can confirm users’ identities with security certificates in two ways:
Using the information in the client certificate as proof of identity
Verifying a client certificate published in an LDAP directory (additional)
When you set the server to use certificate information for authenticating the client, the server:
Checks first if the certificate is from a trusted CA. If not, the authentication fails and the transaction is ended.
Checks the ACL rules specified for that user if the certificate maps correctly. Even if the certificate maps correctly, ACL rules can deny the user access.
Requiring client authentication to control access to specific resources differs from requiring client authentication for all connections to the server. If you set the server to require client authentication for all connections, the client only needs to present a valid certificate issued by a trusted CA. If you set the server’s access control to use the SSL method for authentication of users and groups, the client will need to:
Present a valid certificate issued by a trusted CA
The certificate must be mapped to a valid user in LDAP
The access control list must evaluate properly
When you require client authentication with access control, you need to have SSL ciphers enabled for your web server.
In order to successfully gain access to an SSL authenticated resource, the client certificate must be from a CA trusted by the web server. The client certificate needs to be published in a directory server if the web server’s certmap.conf file is configured to compare the client’s certificate in the browser with the client certificate in the directory server. However, the certmap.conf file can be configured to only compare selected information from the certificate to the directory server entry. For example, you could configure the certmap.conf file to only compare the user ID and email address in the browser certificate with the directory server entry.
Only the SSL authentication method requires modification to the certmap.conf file, because the certificate is checked against the LDAP directory. Requiring client authentication for all connections to the server does not require modification to the certmap.conf file. If you choose to use client certificates, you should increase the value of the AcceptTimeout directive in the magnus.conf file.