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Inconsistent documentation and behavior on non-root -i -p -r -t restrictions #29

cranderson opened this Issue · 0 comments

1 participant


Tested on fping 3.3.

The usage output says:

fping: these options are too risky for mere mortals.
fping: You need i >= 10, p >= 20, r < 20, and t >= 50

The manual page says differently (and is missing the restriction on the -p option):

If certain options are used (i.e, a low value for -i and -t, and a high
value for -r) it is possible to flood the network. This program must be
installed as setuid root in order to open up a raw socket, or must be
run by root. In order to stop mere mortals from hosing the network,
normal users can't specify the following:

   ·   -i n, where n < 10 msec

   ·   -r n, where n > 20

   ·   -t n, where n < 250 msec

The actual behavior that non-root is allowed to do is different from both of the above documentations (Usage message is mostly correct, only -r has a < instead of the more correct <=):

-i >= 10
-p >= 20
-r <= 20
-t >= 50

Finally, the usage message "default" values change to show what you gave on the command line when specifying out-of-range values for non-root users. E.g. if as non-root you specify -i9 you see:

fping: You need i >= 10, p >= 20, r < 20, and t >= 50

Usage: fping [options] [targets...]
-i n interval between sending ping packets (in millisec) (default 9) <----- the default changed here to the actual value given

The same is true for -i, -p, and -t. The -r option default value always displays correctly.

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