From e7d04dd2df8bb935c61f7c814ee88eba7e75b5e4 Mon Sep 17 00:00:00 2001 From: "Yann E. MORIN" Date: Tue, 14 Jul 2015 00:44:01 +0200 Subject: [PATCH] package/dropbear: fix generating keys on RO file systems dropbear generates its keys at the first connection, and wants to save them in /etc/dropbear (not configurable). Currently, our /etc/dropbear is a directory. When the filesystem is read-only, dropbear can't save its keys, so refuses all connections. Fix that with: - at build time, create /etc/dropbear as a symlink to /var/run/dropbear - at runtime, if the filesystem is RW (we can rm /etc/dropbear), we replace the symlink with an actual directory; otherwise, when the filesystem is RO (we can't rm /etc/dropbear), we create /var/run/dropbear so the symlink points to an existing directory Signed-off-by: "Yann E. MORIN" Cc: Thomas Petazzoni Cc: Arnout Vandecappelle Cc: Maxime Hadjinlian Acked-by: "Maxime Hadjinlian" Signed-off-by: Thomas Petazzoni --- package/dropbear/S50dropbear | 14 ++++++++++++++ package/dropbear/dropbear.mk | 2 +- package/dropbear/dropbear.service | 13 +++++++++++++ 3 files changed, 28 insertions(+), 1 deletion(-) diff --git a/package/dropbear/S50dropbear b/package/dropbear/S50dropbear index 2694931d01..af50ccf254 100644 --- a/package/dropbear/S50dropbear +++ b/package/dropbear/S50dropbear @@ -11,6 +11,20 @@ start() { echo -n "Starting dropbear sshd: " umask 077 + + # If /etc/dropbear is not a directory, and + # - the filesystem is RO (i.e. we can not rm the symlink), + # create the directory pointed to by the symlink. + # - the filesystem is RW (i.e. we can rm the symlink), + # replace the symlink with an actual directory + if ! [ -d /etc/dropbear ]; then + if rm -f /etc/dropbear; then + mkdir -p /etc/dropbear + else + mkdir -p $(readlink /etc/dropbear) + fi + fi + start-stop-daemon -S -q -p /var/run/dropbear.pid \ --exec /usr/sbin/dropbear -- $DROPBEAR_ARGS [ $? = 0 ] && echo "OK" || echo "FAIL" diff --git a/package/dropbear/dropbear.mk b/package/dropbear/dropbear.mk index bc65d69c05..5bbe864500 100644 --- a/package/dropbear/dropbear.mk +++ b/package/dropbear/dropbear.mk @@ -93,7 +93,7 @@ define DROPBEAR_INSTALL_TARGET_CMDS for f in $(DROPBEAR_TARGET_BINS); do \ ln -snf ../sbin/dropbear $(TARGET_DIR)/usr/bin/$$f ; \ done - mkdir -p $(TARGET_DIR)/etc/dropbear + ln -snf ../var/run/dropbear $(TARGET_DIR)/etc/dropbear endef $(eval $(autotools-package)) diff --git a/package/dropbear/dropbear.service b/package/dropbear/dropbear.service index 4e6c8795a1..0e2cf548d3 100644 --- a/package/dropbear/dropbear.service +++ b/package/dropbear/dropbear.service @@ -3,6 +3,19 @@ Description=Dropbear SSH daemon After=syslog.target network.target auditd.service [Service] +# If /etc/dropbear is not a directory, and +# - the filesystem is RO (i.e. we can not rm the symlink), +# create the directory pointed to by the symlink. +# - the filesystem is RW (i.e. we can rm the symlink), +# replace the symlink with an actual directory +ExecStartPre=/bin/sh -c '\ +if ! [ -d /etc/dropbear ]; then \ + if rm -f /etc/dropbear; then \ + mkdir -p /etc/dropbear; \ + else \ + mkdir -p $(readlink /etc/dropbear); \ + fi; \ +fi' ExecStart=/usr/sbin/dropbear -F -R ExecReload=/bin/kill -HUP $MAINPID -- 2.30.2