btrbk

ssh_filter_btrbk Man Page

ssh_filter_btrbk(1),version 0.26.0,2017-10-11

NAME

ssh_filter_btrbk - ssh command filter script for btrbk

SYNOPSIS

ssh_filter_btrbk.sh [-s|--source] [-t|--target] [-d|--delete]
    [-c|--compress] [-i|--info] [--snapshot] [--send] [--receive]
    [-p|--restrict-path <path>] [-l|--log] [--sudo]

DESCRIPTION

ssh_filter_btrbk.sh restricts SSH commands to btrfs commands used by btrbk. It examines the SSH_ORIGINAL_COMMAND environment variable (set by sshd) and executes it only if it matches commands used by btrbk. The accepted commands are specified by the "--source", "--target", "--delete" and "--info" options.

Note that the following btrfs commands are always allowed: "btrfs subvolume show", "btrfs subvolume list".

Note that commands for stream compression (pipes through gzip, pigz, bzip2, pbzip2, xz, lzop, lz4), rate limiting (pipes through "pv -L"), and stream buffer (pipes through "mbuffer") are always allowed.

Example line in /root/.ssh/authorized_keys on a backup target host:

command="ssh_filter_btrbk.sh --target --delete --restrict-path /mnt/btr_backup" ssh-rsa AAAAB3NzaC1...hwumXFRQBL btrbk@mydomain.com

OPTIONS

-s, --source

Allow commands for backup source: "btrfs subvolume snapshot", "btrfs send". Equivalent to "--snapshot --send".

-t, --target

Allow commands for backup target: "btrfs receive", "realpath" and "cat /proc/self/mounts".

-d, --delete

Allow commands for subvolume deletion: "btrfs subvolume delete". This is used for backup source if snapshot_preserve_daily is not set to “all”, and for backup targets if target_preserve_daily is not set to “all”.

-c, --compress

Allow commands for stream compression (pipes through gzip, pigz, bzip2, pbzip2, xz, lzo, lz4). Needed if stream_compress is set.

-i, --info

Allow informative commands: "btrfs subvolume find-new", "btrfs filesystem usage". This is used by btrbk info and diff commands.

--snapshot

Allow btrfs snapshot command: "btrfs subvolume snapshot".

--send

Allow btrfs send command: "btrfs send".

--receive

Allow btrfs receive command: "btrfs receive".

-p, --restrict-path <path>

Restrict btrfs commands to <path>.

-l, --log

Log ACCEPT and REJECT messages to the system log.

--sudo

Allow btrfs commands to be called via sudo. Enable this if you have "backend btrfs-progs-sudo" in your btrbk configuration file.

AVAILABILITY

Please refer to the btrbk project page https://digint.ch/btrbk/ for further details.

SEE ALSO

btrbk(1), btrbk.conf(5), btrfs(8)

AUTHOR

Axel Burri <axel@tty0.ch>