pop3d: make tls more configurable

The "tls" statement can be used both within a server declaration
and in the global scope, the former overriding the latter.  Its
argument can be one of the following:

  no          TLS is not used.  The STLS command won't be available even
              if the tls configuration is otherwise complete.
  ondemand    TLS is initiated when the user issues the STLS command.
              This is the default when TLS is configured.
  required    Same as above, but the use of STLS is mandatory.  The
              authentication state is entered only after TLS negotiation
              has succeeded.
  connection  TLS is always forced when the connection is established (pops).

For compatibility with prior versions the tls-required statement is retained,
but is considered deprecated.  It is synonymous with "tls required".  The
"tls" statement allows for the following alias values:

  false, off, 0           same as  no
  stls                    same as  ondemand
  yes, true, on, 1        same as  connection

Internally, all handler functions receive a pointer to the POP session
structure, which configures the current session.  In particular, it
contains the TLS mode and capability list.

* pop3d/capa.c (pop3d_capa): Traverse the capability list,
outputting each of its elements.
(pop3d_session_init)
(pop3d_session_free): New functions.
* pop3d/logindelay.c (login_delay_capa): Change signature.
* pop3d/pop3d.c (tls_required): Remove.
(tls_mode): New variable.
(pop3d_srv_config) <tls>: Remove.
(pop3d_srv_config) <tls_mode>: New member.
(pop3d_srv_param): Change definition of the "tls" statement.
(pop3d_cfg_param): New statement "tls". Mark "tls-required"
as deprecated.
(pop3d_mainloop): Change type of the tls argument.
Initialize session and pass it to each handler.
(pop3d_connection): Decide whether and how to use TLS
using global and per-session settings, the latter
overriding the former.
* pop3d/pop3d.h (login_delay_capa): Change signature.
(tls_mode): New enum.
(pop3d_capa_type): New enum.
(pop3d_capa, pop3d_session): New structs.
(pop3d_session_init)
(pop3d_session_free): New protos.
(pop3d_command_handler_t): Change signature. All handlers and their
uses are changed accordingly.
* pop3d/stls.c (pop3d_stls): Return error if session does not
allow tls.

0 files changed, 0 insertions, 0 deletions