From: epeisach@mit.edu
Subject: SVN Commit

read_entropy_from_device() will loop in read until the desired number
of bytes are read from the device (/dev/random, /dev/urandom).  I have
observed that for /dev/random, if there is not enough bits available
for reading - it will return a partial read.  The code would loop in
this case, but never advance the location to place the new bytes -
hence the start of the buffer would be filled again - leaving the tail
end as stack garbage.



Commit By: epeisach



Revision: 19845
Changed Files:
U   trunk/src/lib/crypto/prng.c

From: tlyu@mit.edu
Subject: SVN Commit

pull up r19845 from trunk

 r19845@cathode-dark-space:  epeisach | 2007-08-20 10:50:41 -0400
 ticket: new
 subject: read_entropy_from_device on partial read will not fill buffer
 tags: pullup

 read_entropy_from_device() will loop in read until the desired number
 of bytes are read from the device (/dev/random, /dev/urandom).  I have
 observed that for /dev/random, if there is not enough bits available
 for reading - it will return a partial read.  The code would loop in
 this case, but never advance the location to place the new bytes -
 hence the start of the buffer would be filled again - leaving the tail
 end as stack garbage.





Commit By: tlyu



Revision: 19906
Changed Files:
_U  branches/krb5-1-6/
U   branches/krb5-1-6/src/lib/crypto/prng.c