base-files: seed /dev/urandom

[openwrt/openwrt.git] / package / base-files / files / etc / init.d / urandom_seed

diff --git a/package/base-files/files/etc/init.d/urandom_seed b/package/base-files/files/etc/init.d/urandom_seed
new file mode 100755 (executable)
index 0000000..cb2eb44
--- /dev/null
+++ b/package/base-files/files/etc/init.d/urandom_seed
@@ -0,0 +1,29 @@
+#!/bin/sh /etc/rc.common
+
+START=99
+
+EXTRA_COMMANDS="save"
+
+_log() {
+    logger -t urandom_seed "$1"
+}
+
+_save() {
+    touch $1.tmp || { _log "touch $1 failed"; return; }
+    chown root:root $1.tmp || { _log "chown $1 failed"; return; }
+    chmod 600 $1.tmp || { _log "chmod $1 failed"; return; }
+    getrandom 512 > $1.tmp || { _log "getrandom failed"; return; }
+    mv $1.tmp $1 || { _log "mv $1 failed"; return; }
+}
+
+save() {
+    SEED="$(uci -q get system.@system[0].urandom_seed)"
+    [ "${SEED:0:1}" == "/" ] && _save "$SEED" && _log "Seed saved ($SEED)"
+
+    SEED=/etc/urandom.seed
+    [ ! -f $SEED ] && _save "$SEED" && _log "Seed saved ($SEED)"
+}
+
+boot() {
+    save
+}