[Asterisk-code-review] res pjsip: Add ability to identify by Authorization username (asterisk[13])

[George Joseph]

Hello Kevin Harwell, Anonymous Coward #1000019, Joshua Colp,

I'd like you to reexamine a change.  Please visit

    https://gerrit.asterisk.org/2367

to look at the new patch set (#17).

Change subject: res_pjsip:  Add ability to identify by Authorization username
......................................................................

res_pjsip:  Add ability to identify by Authorization username

A feature of chan_sip that service providers relied upon was the ability to
identify by the Authorization username.  This is most often used when customers
have a PBX that needs to register rather than identify by IP address.  From my
own experiance, this is pretty common with small businesses who otherwise
don't need a static IP.

In this scenario, a register from the customer's PBX may succeed because From
will usually contain the PBXs account id but an INVITE will contain the caller
id.  With nothing recognizable in From, the service provider's Asterisk can
never match to an endpoint and the INVITE just stays unauthorized.

The fixes:

A new value "auth_username" has been added to endpoint/identify_by that
will use the username and digest fields in the Authorization header
instead of username and domain in the the From header to match an endpoint,
or the To header to match an aor.  This code as added to
res_pjsip_endpoint_identifier_user rather than creating a new module.

Although identify_by was always a comma-separated list, there was only
1 choice so order wasn't preserved.  So to keep the order, a vector was added
to the end of ast_sip_endpoint.  This is only used by res_pjsip_registrar
to find the aor.  The res_pjsip_endpoint_identifier_* modules are called in
globals/endpoint_identifier_order.

Along the way, the logic in res_pjsip_registrar was corrected to match
most-specific to least-specific as res_pjsip_endpoint_identifier_user does.

The order is:

username at domain
username at domain_alias
username

Auth by username does present 1 problem however, the first INVITE won't have
an Authorization header so the distributor, not finding a match on anything,
sends a securty_alert.  It still sends a 401 with a challenge so the next
INVITE will have the Authorization header and presumably succeed.  As a result
though, that first security alert is actually a false alarm.

To address this, a new feature has been added to pjsip_distributor that keeps
track of unidentified requests and only sends the security alert if a
configurable number of unidentified requests come from the same IP in a
configurable amout of time.  Those configuration options have been added to
the global config object.  This feature is only used when auth_username
is enabled.

Finally, default_realm was added to the globals object to replace the hard
coded "asterisk" used when an endpoint is not yet identified.

The testsuite tests all pass but new tests are forthcoming for this new
feature.

ASTERISK-25835 #close
Reported-by: Ross Beer

Change-Id: I30ba62d208e6f63439600916fcd1c08a365ed69d
---
M CHANGES
M configs/samples/pjsip.conf.sample
A contrib/ast-db-manage/config/versions/65eb22eb195_add_unidentified_request_options_to_.py
M include/asterisk/res_pjsip.h
M res/res_pjsip.c
M res/res_pjsip/config_global.c
M res/res_pjsip/pjsip_configuration.c
M res/res_pjsip/pjsip_distributor.c
M res/res_pjsip_authenticator_digest.c
M res/res_pjsip_endpoint_identifier_user.c
M res/res_pjsip_registrar.c
11 files changed, 834 insertions(+), 77 deletions(-)


  git pull ssh://gerrit.asterisk.org:29418/asterisk refs/changes/67/2367/17
-- 
To view, visit https://gerrit.asterisk.org/2367
To unsubscribe, visit https://gerrit.asterisk.org/settings

Gerrit-MessageType: newpatchset
Gerrit-Change-Id: I30ba62d208e6f63439600916fcd1c08a365ed69d
Gerrit-PatchSet: 17
Gerrit-Project: asterisk
Gerrit-Branch: 13
Gerrit-Owner: George Joseph <george.joseph at fairview5.com>
Gerrit-Reviewer: Anonymous Coward #1000019
Gerrit-Reviewer: George Joseph <george.joseph at fairview5.com>
Gerrit-Reviewer: Joshua Colp <jcolp at digium.com>
Gerrit-Reviewer: Kevin Harwell <kharwell at digium.com>
Gerrit-Reviewer: Mark Michelson <mmichelson at digium.com>