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Diffstat (limited to '')
| -rw-r--r-- | contrib/ssh-copy-id | 377 | ||||
| -rw-r--r-- | contrib/ssh-copy-id.1 | 198 |
2 files changed, 575 insertions, 0 deletions
diff --git a/contrib/ssh-copy-id b/contrib/ssh-copy-id new file mode 100644 index 0000000..cd122de --- /dev/null +++ b/contrib/ssh-copy-id @@ -0,0 +1,377 @@ +#!/bin/sh + +# Copyright (c) 1999-2020 Philip Hands <phil@hands.com> +# 2020 Matthias Blümel <blaimi@blaimi.de> +# 2017 Sebastien Boyron <seb@boyron.eu> +# 2013 Martin Kletzander <mkletzan@redhat.com> +# 2010 Adeodato =?iso-8859-1?Q?Sim=F3?= <asp16@alu.ua.es> +# 2010 Eric Moret <eric.moret@gmail.com> +# 2009 Xr <xr@i-jeuxvideo.com> +# 2007 Justin Pryzby <justinpryzby@users.sourceforge.net> +# 2004 Reini Urban <rurban@x-ray.at> +# 2003 Colin Watson <cjwatson@debian.org> +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions +# are met: +# 1. Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# 2. Redistributions in binary form must reproduce the above copyright +# notice, this list of conditions and the following disclaimer in the +# documentation and/or other materials provided with the distribution. +# +# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +# Shell script to install your public key(s) on a remote machine +# See the ssh-copy-id(1) man page for details + +# shellcheck shell=dash + +# check that we have something mildly sane as our shell, or try to find something better +if false ^ printf "%s: WARNING: ancient shell, hunting for a more modern one... " "$0" +then + SANE_SH=${SANE_SH:-/usr/bin/ksh} + if printf 'true ^ false\n' | "$SANE_SH" + then + printf "'%s' seems viable.\\n" "$SANE_SH" + exec "$SANE_SH" "$0" "$@" + else + cat <<-EOF + oh dear. + + If you have a more recent shell available, that supports \$(...) etc. + please try setting the environment variable SANE_SH to the path of that + shell, and then retry running this script. If that works, please report + a bug describing your setup, and the shell you used to make it work. + + EOF + printf '%s: ERROR: Less dimwitted shell required.\n' "$0" + exit 1 + fi +fi + +# shellcheck disable=SC2010 +DEFAULT_PUB_ID_FILE=$(ls -t "${HOME}"/.ssh/id*.pub 2>/dev/null | grep -v -- '-cert.pub$' | head -n 1) +SSH="ssh -a -x" +umask 0177 + +usage () { + printf 'Usage: %s [-h|-?|-f|-n|-s] [-i [identity_file]] [-p port] [-F alternative ssh_config file] [[-o <ssh -o options>] ...] [user@]hostname\n' "$0" >&2 + printf '\t-f: force mode -- copy keys without trying to check if they are already installed\n' >&2 + printf '\t-n: dry run -- no keys are actually copied\n' >&2 + printf '\t-s: use sftp -- use sftp instead of executing remote-commands. Can be useful if the remote only allows sftp\n' >&2 + printf '\t-h|-?: print this help\n' >&2 + exit 1 +} + +# escape any single quotes in an argument +quote() { + printf '%s\n' "$1" | sed -e "s/'/'\\\\''/g" +} + +use_id_file() { + L_ID_FILE="$1" + + if [ -z "$L_ID_FILE" ] ; then + printf '%s: ERROR: no ID file found\n' "$0" + exit 1 + fi + + if expr "$L_ID_FILE" : '.*\.pub$' >/dev/null ; then + PUB_ID_FILE="$L_ID_FILE" + else + PUB_ID_FILE="$L_ID_FILE.pub" + fi + + [ "$FORCED" ] || PRIV_ID_FILE=$(dirname "$PUB_ID_FILE")/$(basename "$PUB_ID_FILE" .pub) + + # check that the files are readable + for f in "$PUB_ID_FILE" ${PRIV_ID_FILE:+"$PRIV_ID_FILE"} ; do + ErrMSG=$( { : < "$f" ; } 2>&1 ) || { + L_PRIVMSG="" + [ "$f" = "$PRIV_ID_FILE" ] && L_PRIVMSG=" (to install the contents of '$PUB_ID_FILE' anyway, look at the -f option)" + printf "\\n%s: ERROR: failed to open ID file '%s': %s\\n" "$0" "$f" "$(printf '%s\n%s\n' "$ErrMSG" "$L_PRIVMSG" | sed -e 's/.*: *//')" + exit 1 + } + done + printf '%s: INFO: Source of key(s) to be installed: "%s"\n' "$0" "$PUB_ID_FILE" >&2 + GET_ID="cat \"$PUB_ID_FILE\"" +} + +if [ -n "$SSH_AUTH_SOCK" ] && ssh-add -L >/dev/null 2>&1 ; then + GET_ID="ssh-add -L" +fi + +while getopts "i:o:p:F:fnsh?" OPT +do + case "$OPT" in + i) + [ "${SEEN_OPT_I}" ] && { + printf '\n%s: ERROR: -i option must not be specified more than once\n\n' "$0" + usage + } + SEEN_OPT_I="yes" + use_id_file "${OPTARG:-$DEFAULT_PUB_ID_FILE}" + ;; + o|p|F) + SSH_OPTS="${SSH_OPTS:+$SSH_OPTS }-$OPT '$(quote "${OPTARG}")'" + ;; + f) + FORCED=1 + ;; + n) + DRY_RUN=1 + ;; + s) + SFTP=sftp + ;; + h|\?) + usage + ;; + esac +done +#shift all args to keep only USER_HOST +shift $((OPTIND-1)) + +if [ $# = 0 ] ; then + usage +fi +if [ $# != 1 ] ; then + printf '%s: ERROR: Too many arguments. Expecting a target hostname, got: %s\n\n' "$0" "$SAVEARGS" >&2 + usage +fi + +# drop trailing colon +USER_HOST="$*" +# tack the hostname onto SSH_OPTS +SSH_OPTS="${SSH_OPTS:+$SSH_OPTS }'$(quote "$USER_HOST")'" +# and populate "$@" for later use (only way to get proper quoting of options) +eval set -- "$SSH_OPTS" + +# shellcheck disable=SC2086 +if [ -z "$(eval $GET_ID)" ] && [ -r "${PUB_ID_FILE:=$DEFAULT_PUB_ID_FILE}" ] ; then + use_id_file "$PUB_ID_FILE" +fi + +# shellcheck disable=SC2086 +if [ -z "$(eval $GET_ID)" ] ; then + printf '%s: ERROR: No identities found\n' "$0" >&2 + exit 1 +fi + +# filter_ids() +# tries to log in using the keys piped to it, and filters out any that work +filter_ids() { + L_SUCCESS="$1" + L_TMP_ID_FILE="$SCRATCH_DIR"/popids_tmp_id + L_OUTPUT_FILE="$SCRATCH_DIR"/popids_output + + # repopulate "$@" inside this function + eval set -- "$SSH_OPTS" + + while read -r ID || [ "$ID" ] ; do + printf '%s\n' "$ID" > "$L_TMP_ID_FILE" + + # the next line assumes $PRIV_ID_FILE only set if using a single id file - this + # assumption will break if we implement the possibility of multiple -i options. + # The point being that if file based, ssh needs the private key, which it cannot + # find if only given the contents of the .pub file in an unrelated tmpfile + $SSH -i "${PRIV_ID_FILE:-$L_TMP_ID_FILE}" \ + -o ControlPath=none \ + -o LogLevel=INFO \ + -o PreferredAuthentications=publickey \ + -o IdentitiesOnly=yes "$@" exit >"$L_OUTPUT_FILE" 2>&1 </dev/null + if [ "$?" = "$L_SUCCESS" ] || { + [ "$SFTP" ] && grep 'allows sftp connections only' "$L_OUTPUT_FILE" >/dev/null + # this error counts as a success if we're setting up an sftp connection + } + then + : > "$L_TMP_ID_FILE" + else + grep 'Permission denied' "$L_OUTPUT_FILE" >/dev/null || { + sed -e 's/^/ERROR: /' <"$L_OUTPUT_FILE" >"$L_TMP_ID_FILE" + cat >/dev/null #consume the other keys, causing loop to end + } + fi + + cat "$L_TMP_ID_FILE" + done +} + +# populate_new_ids() uses several global variables ($USER_HOST, $SSH_OPTS ...) +# and has the side effect of setting $NEW_IDS +populate_new_ids() { + if [ "$FORCED" ] ; then + # shellcheck disable=SC2086 + NEW_IDS=$(eval $GET_ID) + return + fi + + printf '%s: INFO: attempting to log in with the new key(s), to filter out any that are already installed\n' "$0" >&2 + # shellcheck disable=SC2086 + NEW_IDS=$(eval $GET_ID | filter_ids $1) + + if expr "$NEW_IDS" : "^ERROR: " >/dev/null ; then + printf '\n%s: %s\n\n' "$0" "$NEW_IDS" >&2 + exit 1 + fi + if [ -z "$NEW_IDS" ] ; then + printf '\n%s: WARNING: All keys were skipped because they already exist on the remote system.\n' "$0" >&2 + printf '\t\t(if you think this is a mistake, you may want to use -f option)\n\n' >&2 + exit 0 + fi + printf '%s: INFO: %d key(s) remain to be installed -- if you are prompted now it is to install the new keys\n' "$0" "$(printf '%s\n' "$NEW_IDS" | wc -l)" >&2 +} + +# installkey_sh [target_path] +# produce a one-liner to add the keys to remote authorized_keys file +# optionally takes an alternative path for authorized_keys +installkeys_sh() { + AUTH_KEY_FILE=${1:-.ssh/authorized_keys} + AUTH_KEY_DIR=$(dirname "${AUTH_KEY_FILE}") + + # In setting INSTALLKEYS_SH: + # the tr puts it all on one line (to placate tcsh) + # (hence the excessive use of semi-colons (;) ) + # then in the command: + # cd to be at $HOME, just in case; + # the -z `tail ...` checks for a trailing newline. The echo adds one if was missing + # the cat adds the keys we're getting via STDIN + # and if available restorecon is used to restore the SELinux context + INSTALLKEYS_SH=$(tr '\t\n' ' ' <<-EOF + cd; + umask 077; + mkdir -p "${AUTH_KEY_DIR}" && + { [ -z \`tail -1c ${AUTH_KEY_FILE} 2>/dev/null\` ] || + echo >> "${AUTH_KEY_FILE}" || exit 1; } && + cat >> "${AUTH_KEY_FILE}" || exit 1; + if type restorecon >/dev/null 2>&1; then + restorecon -F "${AUTH_KEY_DIR}" "${AUTH_KEY_FILE}"; + fi + EOF + ) + + # to defend against quirky remote shells: use 'exec sh -c' to get POSIX; + printf "exec sh -c '%s'" "${INSTALLKEYS_SH}" +} + +#shellcheck disable=SC2120 # the 'eval set' confuses this +installkeys_via_sftp() { + + # repopulate "$@" inside this function + eval set -- "$SSH_OPTS" + + L_KEYS=$SCRATCH_DIR/authorized_keys + L_SHARED_CON=$SCRATCH_DIR/master-conn + $SSH -f -N -M -S "$L_SHARED_CON" "$@" + L_CLEANUP="$SSH -S $L_SHARED_CON -O exit 'ignored' >/dev/null 2>&1 ; $SCRATCH_CLEANUP" + #shellcheck disable=SC2064 + trap "$L_CLEANUP" EXIT TERM INT QUIT + sftp -b - -o "ControlPath=$L_SHARED_CON" "ignored" <<-EOF || return 1 + -get .ssh/authorized_keys $L_KEYS + EOF + # add a newline or create file if it's missing, same like above + [ -z "$(tail -1c "$L_KEYS" 2>/dev/null)" ] || echo >> "$L_KEYS" + # append the keys being piped in here + cat >> "$L_KEYS" + sftp -b - -o "ControlPath=$L_SHARED_CON" "ignored" <<-EOF || return 1 + -mkdir .ssh + chmod 700 .ssh + put $L_KEYS .ssh/authorized_keys + chmod 600 .ssh/authorized_keys + EOF + #shellcheck disable=SC2064 + eval "$L_CLEANUP" && trap "$SCRATCH_CLEANUP" EXIT TERM INT QUIT +} + + +# create a scratch dir for any temporary files needed +if SCRATCH_DIR=$(mktemp -d ~/.ssh/ssh-copy-id.XXXXXXXXXX) && + [ "$SCRATCH_DIR" ] && [ -d "$SCRATCH_DIR" ] +then + chmod 0700 "$SCRATCH_DIR" + SCRATCH_CLEANUP="rm -rf \"$SCRATCH_DIR\"" + #shellcheck disable=SC2064 + trap "$SCRATCH_CLEANUP" EXIT TERM INT QUIT +else + printf '%s: ERROR: failed to create required temporary directory under ~/.ssh\n' "$0" >&2 + exit 1 +fi + +REMOTE_VERSION=$($SSH -v -o PreferredAuthentications=',' -o ControlPath=none "$@" 2>&1 | + sed -ne 's/.*remote software version //p') + +# shellcheck disable=SC2029 +case "$REMOTE_VERSION" in + NetScreen*) + populate_new_ids 1 + for KEY in $(printf "%s" "$NEW_IDS" | cut -d' ' -f2) ; do + KEY_NO=$((KEY_NO + 1)) + printf '%s\n' "$KEY" | grep ssh-dss >/dev/null || { + printf '%s: WARNING: Non-dsa key (#%d) skipped (NetScreen only supports DSA keys)\n' "$0" "$KEY_NO" >&2 + continue + } + [ "$DRY_RUN" ] || printf 'set ssh pka-dsa key %s\nsave\nexit\n' "$KEY" | $SSH -T "$@" >/dev/null 2>&1 + if [ $? = 255 ] ; then + printf '%s: ERROR: installation of key #%d failed (please report a bug describing what caused this, so that we can make this message useful)\n' "$0" "$KEY_NO" >&2 + else + ADDED=$((ADDED + 1)) + fi + done + if [ -z "$ADDED" ] ; then + exit 1 + fi + ;; + dropbear*) + populate_new_ids 0 + [ "$DRY_RUN" ] || printf '%s\n' "$NEW_IDS" | \ + $SSH "$@" "$(installkeys_sh /etc/dropbear/authorized_keys)" \ + || exit 1 + ADDED=$(printf '%s\n' "$NEW_IDS" | wc -l) + ;; + *) + # Assuming that the remote host treats ~/.ssh/authorized_keys as one might expect + populate_new_ids 0 + if ! [ "$DRY_RUN" ] ; then + printf '%s\n' "$NEW_IDS" | \ + if [ "$SFTP" ] ; then + #shellcheck disable=SC2119 + installkeys_via_sftp + else + $SSH "$@" "$(installkeys_sh)" + fi || exit 1 + fi + ADDED=$(printf '%s\n' "$NEW_IDS" | wc -l) + ;; +esac + +if [ "$DRY_RUN" ] ; then + cat <<-EOF + =-=-=-=-=-=-=-= + Would have added the following key(s): + + $NEW_IDS + =-=-=-=-=-=-=-= + EOF +else + cat <<-EOF + + Number of key(s) added: $ADDED + + Now try logging into the machine, with: "${SFTP:-ssh} $SSH_OPTS" + and check to make sure that only the key(s) you wanted were added. + + EOF +fi + +# =-=-=-= diff --git a/contrib/ssh-copy-id.1 b/contrib/ssh-copy-id.1 new file mode 100644 index 0000000..c141a29 --- /dev/null +++ b/contrib/ssh-copy-id.1 @@ -0,0 +1,198 @@ +.ig \" -*- nroff -*- +Copyright (c) 1999-2020 hands.com Ltd. <http://hands.com/> + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions +are met: +1. Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. +2. Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + +THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.. +.Dd $Mdocdate: June 17 2010 $ +.Dt SSH-COPY-ID 1 +.Os +.Sh NAME +.Nm ssh-copy-id +.Nd use locally available keys to authorise logins on a remote machine +.Sh SYNOPSIS +.Nm +.Op Fl f +.Op Fl n +.Op Fl s +.Op Fl i Op Ar identity_file +.Op Fl p Ar port +.Op Fl o Ar ssh_option +.Op Ar user Ns @ Ns +.Ar hostname +.Nm +.Fl h | Fl ? +.br +.Sh DESCRIPTION +.Nm +is a script that uses +.Xr ssh 1 +to log into a remote machine (presumably using a login password, +so password authentication should be enabled, unless you've done some +clever use of multiple identities). It assembles a list of one or more +fingerprints (as described below) and tries to log in with each key, to +see if any of them are already installed (of course, if you are not using +.Xr ssh-agent 1 +this may result in you being repeatedly prompted for pass-phrases). +It then assembles a list of those that failed to log in, and using ssh, +enables logins with those keys on the remote server. By default it adds +the keys by appending them to the remote user's +.Pa ~/.ssh/authorized_keys +(creating the file, and directory, if necessary). It is also capable +of detecting if the remote system is a NetScreen, and using its +.Ql set ssh pka-dsa key ... +command instead. +.Pp +The options are as follows: +.Bl -tag -width Ds +.It Fl i Ar identity_file +Use only the key(s) contained in +.Ar identity_file +(rather than looking for identities via +.Xr ssh-add 1 +or in the +.Ic default_ID_file ) . +If the filename does not end in +.Pa .pub +this is added. If the filename is omitted, the +.Ic default_ID_file +is used. +.Pp +Note that this can be used to ensure that the keys copied have the +comment one prefers and/or extra options applied, by ensuring that the +key file has these set as preferred before the copy is attempted. +.It Fl f +Forced mode: doesn't check if the keys are present on the remote server. +This means that it does not need the private key. Of course, this can result +in more than one copy of the key being installed on the remote system. +.It Fl n +do a dry-run. Instead of installing keys on the remote system simply +prints the key(s) that would have been installed. +.It Fl s +SFTP mode: usually the public keys are installed by executing commands on the remote side. +With this option the user's +.Pa ~/.ssh/authorized_keys +file will be downloaded, modified locally and uploaded with sftp. +This option is useful if the server has restrictions on commands which can be used on the remote side. +.It Fl h , Fl ? +Print Usage summary +.It Fl p Ar port , Fl o Ar ssh_option +These two options are simply passed through untouched, along with their +argument, to allow one to set the port or other +.Xr ssh 1 +options, respectively. +.Pp +Rather than specifying these as command line options, it is often better to use (per-host) settings in +.Xr ssh 1 Ns 's +configuration file: +.Xr ssh_config 5 . +.El +.Pp +Default behaviour without +.Fl i , +is to check if +.Ql ssh-add -L +provides any output, and if so those keys are used. Note that this results in +the comment on the key being the filename that was given to +.Xr ssh-add 1 +when the key was loaded into your +.Xr ssh-agent 1 +rather than the comment contained in that file, which is a bit of a shame. +Otherwise, if +.Xr ssh-add 1 +provides no keys contents of the +.Ic default_ID_file +will be used. +.Pp +The +.Ic default_ID_file +is the most recent file that matches: +.Pa ~/.ssh/id*.pub , +(excluding those that match +.Pa ~/.ssh/*-cert.pub ) +so if you create a key that is not the one you want +.Nm +to use, just use +.Xr touch 1 +on your preferred key's +.Pa .pub +file to reinstate it as the most recent. +.Pp +.Sh EXAMPLES +If you have already installed keys from one system on a lot of remote +hosts, and you then create a new key, on a new client machine, say, +it can be difficult to keep track of which systems on which you've +installed the new key. One way of dealing with this is to load both +the new key and old key(s) into your +.Xr ssh-agent 1 . +Load the new key first, without the +.Fl c +option, then load one or more old keys into the agent, possibly by +ssh-ing to the client machine that has that old key, using the +.Fl A +option to allow agent forwarding: +.Pp +.D1 user@newclient$ ssh-add +.D1 user@newclient$ ssh -A old.client +.D1 user@oldl$ ssh-add -c +.D1 No ... prompt for pass-phrase ... +.D1 user@old$ logoff +.D1 user@newclient$ ssh someserver +.Pp +now, if the new key is installed on the server, you'll be allowed in +unprompted, whereas if you only have the old key(s) enabled, you'll be +asked for confirmation, which is your cue to log back out and run +.Pp +.D1 user@newclient$ ssh-copy-id -i someserver +.Pp +The reason you might want to specify the -i option in this case is to +ensure that the comment on the installed key is the one from the +.Pa .pub +file, rather than just the filename that was loaded into your agent. +It also ensures that only the id you intended is installed, rather than +all the keys that you have in your +.Xr ssh-agent 1 . +Of course, you can specify another id, or use the contents of the +.Xr ssh-agent 1 +as you prefer. +.Pp +Having mentioned +.Xr ssh-add 1 Ns 's +.Fl c +option, you might consider using this whenever using agent forwarding +to avoid your key being hijacked, but it is much better to instead use +.Xr ssh 1 Ns 's +.Ar ProxyCommand +and +.Fl W +option, +to bounce through remote servers while always doing direct end-to-end +authentication. This way the middle hop(s) don't get access to your +.Xr ssh-agent 1 . +A web search for +.Ql ssh proxycommand nc +should prove enlightening (N.B. the modern approach is to use the +.Fl W +option, rather than +.Xr nc 1 ) . +.Sh "SEE ALSO" +.Xr ssh 1 , +.Xr ssh-agent 1 , +.Xr sshd 8 |