tree f1d9c54235f01cb5a47f73a3eb3ca082a729f3b9
parent 0ee798a0172a009cec4fb27c427b8f1d66fca749
author Neels Hofmeyr <neels@hofmeyr.de> 1554150273 +0200
committer Harald Welte <laforge@gnumonks.org> 1555191538 +0000

GSUP: add Message Class IE

osmo-msc and osmo-hlr have distinct subsystems handling incoming GSUP messages.
So far we decide entirely by message type which code path should handle a GSUP
message. Thus no GSUP message type may be re-used across subsystems.

If we add a GSUP message to indicate a routing error, it would have to be a
distinct message type for subscriber management, another one for SMS, another
one for USSD...

To allow introducing common message types, introduce a GSUP Message Class IE.

In the presence of this IE, GSUP handlers can trivially direct a received
message to the right code path. If it is missing, handlers can fall back to the
previous switch(message_type) method.

Change-Id: Ic397a9f2c4a7224e47cab944c72e75ca5592efef