NAME
tsi - Transmission Subscriber Identification (TSI) access control list
DESCRIPTION
The HylaFAX configuration parameter QualifyTSI specifies whether or not
the identity of a calling facsimile machine should be checked against
an access control list before receiving facsimile. If QualifyTSI is
non-null, then only messages from facsimile machines identified in the
file specified by the string (typically etc/tsi) will be accepted.
Patterns are specified one per line and must conform to the regular
expressions syntax specified by POSIX 1003.2; see re_format(7).
Comments may be included; they are introduced with the ``#'' character
and extend to the end of the line. Any trailing white space on a line
is ignored (for convenience when comments are used).
If a line begins with ``!'', then the regular expression identifies
clients that should be rejected; otherwise regular expressions identify
clients whose transmissions should be accepted. The order of patterns
in a TSI file is important. When a facsimile is to be received, the
fax server will compare the client's TSI against the patterns in the
access control list in the order in which they appear in the file. The
first pattern that matches the client TSI is used to decide whether to
accept or reject the facsimile. If no patterns match the client TSI
then the facsimile is rejected. Thus if you want to accept all but a
restricted set of TSI the last line in the file should be ``^.*$''.
Note that regular expression patterns should be written to match a TSI
exactly. That is, patterns should be of the form:
^<pattern>$
where the ``^'' and ``$'' characters are used to specify the start and
end of the matching TSI. Additionally, regular expression patterns
should handle white space that may appear in known locations. For
example,
^([+]1){1}[ .-]*415[ .-]*555[ .-]*1212.*$
matches the following TSI strings:
+1.415.555.1212
415 555 1212
1-415-555-1212
Finally, note that regular expressions can be used to specify many TSI
with one pattern.
NOTES
It would be nice if TSI that were to be matched against were placed in
some canonical form (e.g. remove white space and white space-like
characters). This is, however, problematic, because some facsimile
machines permit any printable ASCII string to be sent as a TSI.
SEE ALSO
faxgetty(8), re_format(7), hylafax-config(5)
December 5, 1994