Local Must Be Local
The local part of
an alias must be in the form of a local
recipient.[195] This restriction is enforced each time
sendmail reads the
aliases(5) file. For every
name to the left of a colon that it finds,
sendmail performs the
following normalization and verification
steps.
To begin, sendmail normalizes each address by removing everything but the address part. For example, consider the following two alias lines:
george (George Washington): gw George Washington <george>: gw
When sendmail reads these lines, it normalizes each into its address part:
george (George Washington) becomes → george George Washington <george> becomes → george
Afterward, the address part is extracted and rewritten
by the canonify
rule set 3 and the parse rule set 0, to see whether it
causes any delivery agent with the F=A flag set (F=A on page 767) to be
selected. Generally, local addresses select the
local delivery
agent, which normally has the F=A flag set. Nonlocal
addresses (such as
gw@another.host) generally
select one of the smtp delivery agents, which normally do
not have the F=A
flag set.
Prior to V8.7 sendmail, an
address had to select the local delivery to allow itself to be
aliased.
If the selected delivery agent has the F=u flag set (F=u on page 780), the address
will be converted to lowercase before being looked
up in the aliases
database.
In the earlier example, the address george (after
processing) selects the local delivery agent, and so these alias lines are legal. Internally (or ...
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