initscripts: Use current date as an additional source of entropy

If the seed file is empty or does not exist, the date is an extremely
poor backup source of entropy, but it is better than nothing.

Signed-off-by: Richard Tollerton <rich.tollerton@ni.com>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/recipes-core/initscripts/initscripts-1.0/urandom b/meta/recipes-core/initscripts/initscripts-1.0/urandom
index a0549dec258c356bcaf8536fad22fb42b7a3bb03..ec4ef61f23cce870d77ec4950c23200e8424664c 100755 (executable)
--- a/meta/recipes-core/initscripts/initscripts-1.0/urandom
+++ b/meta/recipes-core/initscripts/initscripts-1.0/urandom
@@ -20,12 +20,11 @@ RANDOM_SEED_FILE=/var/lib/urandom/random-seed
 case "$1" in
        start|"")
                test "$VERBOSE" != no && echo "Initializing random number generator..."
-               # Load and then save 512 bytes,
-               # which is the size of the entropy pool
-               if test -f "$RANDOM_SEED_FILE"
-               then
-                       cat "$RANDOM_SEED_FILE" >/dev/urandom
-               fi
+               # Load and then save 512 bytes, which is the size of the entropy
+               # pool. Also load the current date, in case the seed file is
+               # empty.
+               ( date +%s.%N; [ -f "$RANDOM_SEED_FILE" ] && cat "$RANDOM_SEED_FILE" ) \
+                       >/dev/urandom
                rm -f "$RANDOM_SEED_FILE"
                umask 077
                dd if=/dev/urandom of=$RANDOM_SEED_FILE count=1 \