use /dev/random for crypto-grade RNG with the help of haveged

Rather than pass `-r /dev/random` to ldns-keygen (it was `-r /dev/urandom`),
don't pass `-r` at all since /dev/random is the default.

Merges branch 'master' of github.com:pysiak/mailinabox

setup/dns.sh

@@ -37,17 +37,16 @@ if [ ! -f "$STORAGE_ROOT/dns/dnssec/keys.conf" ]; then
 
 	# Create the Key-Signing Key (KSK) (-k) which is the so-called
 	# Secure Entry Point. Use a NSEC3-compatible algorithm (best
-	# practice), and a nice and long keylength. Use /dev/urandom
-	# instead of /dev/random for noise or else we'll be waiting
-	# a very long time. The domain name we provide ("_domain_")
-	# doesn't matter -- we'll use the same keys for all our domains.
-	KSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -a RSASHA1-NSEC3-SHA1 -b 2048 -k -r /dev/urandom _domain_);
+	# practice), and a nice and long keylength. The domain name we
+	# provide ("_domain_") doesn't matter -- we'll use the same
+	# keys for all our domains.
+	KSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -a RSASHA1-NSEC3-SHA1 -b 2048 -k _domain_);
 
 	# Now create a Zone-Signing Key (ZSK) which is expected to be
 	# rotated more often than a KSK, although we have no plans to
 	# rotate it (and doing so would be difficult to do without
 	# disturbing DNS availability.) Omit '-k' and use a shorter key.
-	ZSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -a RSASHA1-NSEC3-SHA1 -b 1024 -r /dev/urandom _domain_);
+	ZSK=$(umask 077; cd $STORAGE_ROOT/dns/dnssec; ldns-keygen -a RSASHA1-NSEC3-SHA1 -b 1024 _domain_);
 
 	# These generate two sets of files like:
 	# K_domain_.+007+08882.ds <- DS record for adding to NSD configuration files

setup/system.sh

@@ -7,8 +7,12 @@ hide_output apt-get update
 hide_output apt-get -y upgrade
 
 # Install basic utilities.
+#
+#	haveged: Provides extra entropy to /dev/random so it doesn't stall
+#	         when generating random numbers for private keys (e.g. during
+#	         ldns-keygen).
 
-apt_install python3 python3-pip wget curl bind9-host
+apt_install python3 python3-pip wget curl bind9-host haveged
 
 # Turn on basic services:
 #

setup/webmail.sh

@@ -36,7 +36,7 @@ if [ ! -d /usr/local/lib/roundcubemail ]; then
 fi
 
 # Generate a safe 24-character secret key of safe characters.
-SECRET_KEY=$(dd if=/dev/urandom bs=20 count=1 2>/dev/null | base64 | fold -w 24 | head -n 1)
+SECRET_KEY=$(dd if=/dev/random bs=20 count=1 2>/dev/null | base64 | fold -w 24 | head -n 1)
 
 # Create a configuration file.
 #