TACACS: T5577: Added `mandatory` and `optional` modes for TACACS+

In CLI we can choose authentication logic:

  - `mandatory` - if TACACS+ answered with `REJECT`, authentication must be
  stopped and access denied immediately.
  - `optional` (default) - if TACACS+ answers with `REJECT`, authentication
  continues using the next module.

In `mandatory` mode authentication will be stopped only if TACACS+ clearly
answered that access should be denied (no user in TACACS+ database, wrong
password, etc.). If TACACS+ is not available or other errors happen, it will be
skipped and authentication will continue with the next module, like in
`optional` mode.

0 files changed, 0 insertions, 0 deletions