print_help() {
cat <<EOF
Target commands:
-- console
+- console (default command)
- reset
- on
- off
- rsync ...
+- get-config
Management commands:
- help
[ "$NB_ADMIN" ] || return 1
case $# in
- 0) die "Username argument missing";;
+ 0) die "Usage: ssh ... add-key USERNAME < id_rsa.pub";;
1) break;;
*) die "User name must not contain spaces: $*";;
esac
exec_shell() {
[ "$NB_ADMIN" ] || die "Permission denied"
+ if ! tty > /dev/null; then
+ echo "novaboot-shell: Consider starting the shell with 'ssh -t'"
+ fi
exec /bin/bash || exec /bin/sh
}
locked() {
print_queue
- tmp=$(mktemp)
- no_fork=
- flock -h 2>&1 | grep -q -e "--no-fork" && no_fork=--no-fork
- rm -f "$tmp"
- exec flock $no_fork "$RUN_DIR" "$@"
+ exec flock --no-fork "$RUN_DIR" "$@"
}
unlocked() {
NB_ADMIN=
if [ "$1" = "user" ]; then
# Get user name encoded in ~/.ssh/authorized_keys
- NB_USER="$2";
+ export NB_USER="$2";
[ "$3" = "admin" ] && NB_ADMIN=1
set -- $SSH_ORIGINAL_COMMAND
fi
- if [ $# -eq 0 ]; then print_help; fi
-
IP=${SSH_CONNECTION%% *}
- HOST=$(getent hosts $IP) || HOST=$IP
+ if [ "$IP" ]; then
+ HOST=$(getent hosts $IP) || HOST=$IP
+ else
+ HOST=localhost
+ fi
REMOTE=${HOST##* }
DATE=$(LANG=C date +'%F_%T')
export NOVABOOT_ID="${NB_USER:-?} $DATE ${REMOTE}"
case "$1" in
# Commands allowed at any time
- "console") locked $0 console;;
+ "console"|"") locked $0 console;;
"get-config") read_config && echo -n "${target_config}"; exit;;
"add-key") shift; add_key "$@"; exit;;
"shell") exec_shell; exit;;
# Commands allowed only when nobody or the same user is connected
# to the console. "The same user" means that we were executed by
# the same sshd process that has the lock. This is ensured by
- # using SSH connection sharing on cline side.
+ # using SSH connection sharing on client side.
reset | rsync | on | off)
ALLOWED_PPID=$(cat $RUN_DIR/ppid 2>/dev/null || :)
if [ "$PPID" -eq "${ALLOWED_PPID:-0}" ]; then run=unlocked; else run=locked; fi
else
run_subcommand "$@"
fi
+exit
+
+: <<EOF
+=encoding utf8
+
+=head1 NAME
+
+novaboot-shell - provides novaboot with unified SSH-based interface for controlling target hardware
+
+=head1 SYNOPSIS
+
+B<novaboot-shell> -c "[command [arguments...]]"
+
+B<novaboot-shell> [command [arguments...]]
+
+B<ssh target@server> [command [arguments...]]
+
+=head1 DESCRIPTION
+
+B<novaboot-shell> provides L<novaboot(1)> with a unified SSH-based
+interface for controlling the target hardware. This simplifies
+client-side configuration, because clients typically need only the
+I<--ssh=...> option. B<novaboot-shell> is typically configured as a
+login shell of special user accounts associated with the target
+hardware (as set by L<adduser-novaboot(8)>). It ensures that users can
+perform only a limited set of actions (see L</COMMANDS> below) with
+the target and have no shell access on the server.
+
+=head1 COMMANDS
+
+=over 8
+
+=item console
+
+Connect to target console (usually serial line). When somebody is
+connected to the console, other users are blocked from controlling the
+target. Blocked users see a message indicating who blocks them.
+
+The user connected to the console is able to invoke other commands
+such as L</reset>, but only when the command is invoked via the same
+SSH connection. This can be accomplished by using SSH connection
+sharing, which is what L<novaboot(1)> uses (see I<-M> and I<-S> in
+L<ssh(1)>).
+
+This is the default command when no command is specified on command
+line.
+
+=item reset
+
+Reset the target hardware.
+
+=item on
+
+Power on the target hardware.
+
+=item off
+
+Power off the target hardware.
+
+=item rsync [...]
+
+This command is not meant to be invoked directly by the user. It
+allows using L<rsync(1)> to copy files to the target, perhaps for TFTP
+server. The rsync command must be invoked as: C<rsync ...
+target@server:>, i.e. without specifying destination path. The files
+will be stored into I<$HOME/tftproot>.
+
+=item user <uernamename> [admin]
+
+User command is meant to be used with C<command=> option in SSH's
+L<authorized_keys(5)> file. It allows the shell to display
+human-readable names when printing information about who blocks the
+target. Then, the real command is taken from SSH_ORIGINAL_COMMAND
+environment variable.
+
+When "admin" is specified after the user name, this user is considered
+an administrator and is allowed to run L</add-key> and L</shell>
+commands.
+
+=item get-config
+
+Prints novaboot configuration options needed for the target. One
+option per line.
+
+=back
+
+=head2 Administration commands
+
+Only administrators (see L</user>) are allowed to execute these
+commands.
+
+=over 8
+
+=item add-key <username>
+
+Reads the SSH public key from standard input and adds it into in
+F<~/.ssh/authorized_keys>.
+
+Example: C<ssh target@server add-key johndoe < john_rsa.pub>
+
+=item shell
+
+Runs shell on the server. Useful for editing configuration file. It is
+better used with allocated pseudo-terminal.
+
+Example: C<ssh -t target@server shell>
+
+=back
+
+=head1 CONFIGURATION FILE
+
+B<novaboot-shell> reads configuration file from
+F<$HOME/.novaboot-shell>. It should define values for the following
+variables in the SH syntax.
+
+=over 8
+
+=item console_cmd
+
+Command to C<exec> that connects to target's console.
+
+=item reset_cmd
+
+Command to C<exec> that resets the Target.
+
+=item on_cmd
+
+Command to C<exec> that powers the target on.
+
+=item off_cmd
+
+Command to C<exec> that powers the target off.
+
+=item target_config
+
+Novaboot command line options that specify which boot loader is used
+by the target (L<novaboot(1)> rejects other, possibly dangerous, options).
+Each option is on its own line and no quoting, escaping or stripping
+is performed on the values.
+
+Example:
+
+ target_config="\
+ --uboot=(uboot)
+ --uboot-init=setenv serverip 192.168.1.1; setenv ipaddr 192.168.1.10
+ --uboot-addr=kernel=0x8100000
+ --uboot-addr=fdt=0x83000000
+ --uboot-addr=ramdisk=0x83100000
+ "
+
+
+=back
+
+=head1 AUTHORS
+
+Michal Sojka <sojkam1@fel.cvut.cz>
+
+Latest version can be found at
+L<https://github.com/wentasah/novaboot>.
+
+=cut
+EOF
projects / novaboot.git / blobdiff