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Re: default permissions

Russell Coker <russell@coker.com.au> writes:

> The /sbin/MAKEDEV script is inconsistant regarding the permissions for the 
> following devices.  Could someone please suggest what is the right value?
> /dev/openprom
> /dev/random

	This is correct:

crw-rw-rw-    1 root     root       1,   8 Jan  1  1970 /dev/random
crw-rw-rw-    1 root     root       1,   9 Oct 23 21:20 /dev/urandom

	Writing into /dev/{,u}random will do no harm, only stir the
        bytes in the random pool -- it can only improve the randomness,
        by design.

        To really add entropy, root uses a special call (I think it was
        an ioctl) that specifies the amount of entropy fed. That call is
        restricted to root-only.

        (_Really_ security-conscious people will note that read access
        for all allows local users to drain the entropy, creating a
        /dev/random DoS.. I don't think that's really avoidable.)

double a,b=4,c;main(){for(;++a<2e6;c-=(b=-b)/a++);printf("%f\n",c);}

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