/mandos/trunk

#!/bin/sh -e

# 

# Mandos key generator - create new keys for a Mandos client

# 

# Copyright © 2008-2019 Teddy Hogeborn

# Copyright © 2008-2019 Björn Påhlsson

# 

# This file is part of Mandos.

#

# Mandos is free software: you can redistribute it and/or modify it

# under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

#     Mandos is distributed in the hope that it will be useful, but

#     WITHOUT ANY WARRANTY; without even the implied warranty of

#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

#     GNU General Public License for more details.

# 

# You should have received a copy of the GNU General Public License

# along with Mandos.  If not, see <http://www.gnu.org/licenses/>.

# 

# Contact the authors at <mandos@recompile.se>.

# 

VERSION="1.8.17"

KEYDIR="/etc/keys/mandos"

KEYTYPE=RSA

KEYLENGTH=4096

SUBKEYTYPE=RSA

SUBKEYLENGTH=4096

KEYNAME="`hostname --fqdn 2>/dev/null || hostname`"

KEYEMAIL=""

KEYCOMMENT=""

KEYEXPIRE=0

TLS_KEYTYPE=ed25519

FORCE=no

SSH=yes

KEYCOMMENT_ORIG="$KEYCOMMENT"

mode=keygen

if [ ! -d "$KEYDIR" ]; then

    KEYDIR="/etc/mandos/keys"

fi

# Parse options

TEMP=`getopt --options vhpF:d:t:l:s:L:n:e:c:x:T:fS \

    --longoptions version,help,password,passfile:,dir:,type:,length:,subtype:,sublength:,name:,email:,comment:,expire:,tls-keytype:,force,no-ssh \

    --name "$0" -- "$@"`

help(){

basename="`basename "$0"`"

cat <<EOF

Usage: $basename [ -v | --version ]

       $basename [ -h | --help ]

   Key creation:

       $basename [ OPTIONS ]

   Encrypted password creation:

       $basename { -p | --password } [ --name NAME ] [ --dir DIR]

       $basename { -F | --passfile } FILE [ --name NAME ] [ --dir DIR]

Key creation options:

  -v, --version         Show program's version number and exit

  -h, --help            Show this help message and exit

  -d DIR, --dir DIR     Target directory for key files

  -t TYPE, --type TYPE  OpenPGP key type.  Default is RSA.

  -l BITS, --length BITS

                        OpenPGP key length in bits.  Default is 4096.

  -s TYPE, --subtype TYPE

                        OpenPGP subkey type.  Default is RSA.

  -L BITS, --sublength BITS

                        OpenPGP subkey length in bits.  Default 4096.

  -n NAME, --name NAME  Name of key.  Default is the FQDN.

  -e ADDRESS, --email ADDRESS

                        Email address of OpenPGP key.  Default empty.

  -c TEXT, --comment TEXT

                        Comment field for OpenPGP key.  Default empty.

  -x TIME, --expire TIME

                        OpenPGP key expire time.  Default is none.

                        See gpg(1) for syntax.

  -T TYPE, --tls-keytype TYPE

                        TLS key type.  Default is ed25519.

  -f, --force           Force overwriting old key files.

Password creation options:

  -p, --password        Create an encrypted password using the key in

                        the key directory.  All options other than

                        --dir and --name are ignored.

  -F FILE, --passfile FILE

                        Encrypt a password from FILE using the key in

                        the key directory.  All options other than

                        --dir and --name are ignored.

  -S, --no-ssh          Don't get SSH key or set "checker" option.

EOF

}

eval set -- "$TEMP"

while :; do

    case "$1" in

	-p|--password) mode=password; shift;;

	-F|--passfile) mode=password; PASSFILE="$2"; shift 2;;

	-d|--dir) KEYDIR="$2"; shift 2;;

	-t|--type) KEYTYPE="$2"; shift 2;;

	-s|--subtype) SUBKEYTYPE="$2"; shift 2;;

	-l|--length) KEYLENGTH="$2"; shift 2;;

	-L|--sublength) SUBKEYLENGTH="$2"; shift 2;;

	-n|--name) KEYNAME="$2"; shift 2;;

	-e|--email) KEYEMAIL="$2"; shift 2;;

	-c|--comment) KEYCOMMENT="$2"; shift 2;;

	-x|--expire) KEYEXPIRE="$2"; shift 2;;

	-T|--tls-keytype) TLS_KEYTYPE="$2"; shift 2;;

	-f|--force) FORCE=yes; shift;;

	-S|--no-ssh) SSH=no; shift;;

	-v|--version) echo "$0 $VERSION"; exit;;

	-h|--help) help; exit;;

	--) shift; break;;

	*) echo "Internal error" >&2; exit 1;;

    esac

done

if [ "$#" -gt 0 ]; then

    echo "Unknown arguments: '$*'" >&2

    exit 1

fi

SECKEYFILE="$KEYDIR/seckey.txt"

PUBKEYFILE="$KEYDIR/pubkey.txt"

TLS_PRIVKEYFILE="$KEYDIR/tls-privkey.pem"

TLS_PUBKEYFILE="$KEYDIR/tls-pubkey.pem"

# Check for some invalid values

if [ ! -d "$KEYDIR" ]; then

    echo "$KEYDIR not a directory" >&2

    exit 1

fi

if [ ! -r "$KEYDIR" ]; then

    echo "Directory $KEYDIR not readable" >&2

    exit 1

fi

if [ "$mode" = keygen ]; then

    if [ ! -w "$KEYDIR" ]; then

	echo "Directory $KEYDIR not writeable" >&2

	exit 1

    fi

    if [ -z "$KEYTYPE" ]; then

	echo "Empty key type" >&2

	exit 1

    fi

    if [ -z "$KEYNAME" ]; then

	echo "Empty key name" >&2

	exit 1

    fi

    if [ -z "$KEYLENGTH" ] || [ "$KEYLENGTH" -lt 512 ]; then

	echo "Invalid key length" >&2

	exit 1

    fi

    if [ -z "$KEYEXPIRE" ]; then

	echo "Empty key expiration" >&2

	exit 1

    fi

    # Make FORCE be 0 or 1

    case "$FORCE" in

	[Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]) FORCE=1;;

	[Nn][Oo]|[Ff][Aa][Ll][Ss][Ee]|*) FORCE=0;;

    esac

    if { [ -e "$SECKEYFILE" ] || [ -e "$PUBKEYFILE" ] \

	     || [ -e "$TLS_PRIVKEYFILE" ] \

	     || [ -e "$TLS_PUBKEYFILE" ]; } \

	&& [ "$FORCE" -eq 0 ]; then

	echo "Refusing to overwrite old key files; use --force" >&2

	exit 1

    fi

    # Set lines for GnuPG batch file

    if [ -n "$KEYCOMMENT" ]; then

	KEYCOMMENTLINE="Name-Comment: $KEYCOMMENT"

    fi

    if [ -n "$KEYEMAIL" ]; then

	KEYEMAILLINE="Name-Email: $KEYEMAIL"

    fi

    # Create temporary gpg batch file

    BATCHFILE="`mktemp -t mandos-keygen-batch.XXXXXXXXXX`"

    TLS_PRIVKEYTMP="`mktemp -t mandos-keygen-privkey.XXXXXXXXXX`"

fi

if [ "$mode" = password ]; then

    # Create temporary encrypted password file

    SECFILE="`mktemp -t mandos-keygen-secfile.XXXXXXXXXX`"

fi

# Create temporary key ring directory

RINGDIR="`mktemp -d -t mandos-keygen-keyrings.XXXXXXXXXX`"

# Remove temporary files on exit

trap "

set +e; \

test -n \"$SECFILE\" && shred --remove \"$SECFILE\"; \

test -n \"$TLS_PRIVKEYTMP\" && shred --remove \"$TLS_PRIVKEYTMP\"; \

shred --remove \"$RINGDIR\"/sec* 2>/dev/null;

test -n \"$BATCHFILE\" && rm --force \"$BATCHFILE\"; \

rm --recursive --force \"$RINGDIR\";

tty --quiet && stty echo; \

" EXIT

set -e

umask 077

if [ "$mode" = keygen ]; then

    # Create batch file for GnuPG

    cat >"$BATCHFILE" <<-EOF

	Key-Type: $KEYTYPE

	Key-Length: $KEYLENGTH

	Key-Usage: sign,auth

	Subkey-Type: $SUBKEYTYPE

	Subkey-Length: $SUBKEYLENGTH

	Subkey-Usage: encrypt

	Name-Real: $KEYNAME

	$KEYCOMMENTLINE

	$KEYEMAILLINE

	Expire-Date: $KEYEXPIRE

	#Preferences: <string>

	#Handle: <no-spaces>

	#%pubring pubring.gpg

	#%secring secring.gpg

	%no-protection

	%commit

	EOF

    if tty --quiet; then

	cat <<-EOF

	Note: Due to entropy requirements, key generation could take

	anything from a few minutes to SEVERAL HOURS.  Please be

	patient and/or supply the system with more entropy if needed.

	EOF

	echo -n "Started: "

	date

    fi

    # Generate TLS private key

    if certtool --generate-privkey --password='' \

		--outfile "$TLS_PRIVKEYTMP" --sec-param ultra \

		--key-type="$TLS_KEYTYPE" --pkcs8 --no-text 2>/dev/null; then

	# Backup any old key files

	if cp --backup=numbered --force "$TLS_PRIVKEYFILE" "$TLS_PRIVKEYFILE" \

	      2>/dev/null; then

	    shred --remove "$TLS_PRIVKEYFILE" 2>/dev/null || :

	fi

	if cp --backup=numbered --force "$TLS_PUBKEYFILE" "$TLS_PUBKEYFILE" \

	      2>/dev/null; then

	    rm --force "$TLS_PUBKEYFILE"

	fi

	cp --archive "$TLS_PRIVKEYTMP" "$TLS_PRIVKEYFILE"

	shred --remove "$TLS_PRIVKEYTMP" 2>/dev/null || :

	## TLS public key

	# First try certtool from GnuTLS

	if ! certtool --password='' --load-privkey="$TLS_PRIVKEYFILE" \

	     --outfile="$TLS_PUBKEYFILE" --pubkey-info --no-text \

	     2>/dev/null; then

	    # Otherwise try OpenSSL

	    if ! openssl pkey -in "$TLS_PRIVKEYFILE" \

		 -out "$TLS_PUBKEYFILE" -pubout; then

		rm --force "$TLS_PUBKEYFILE"

		# None of the commands succeded; give up

		return 1

	    fi

	fi

    fi

    # Make sure trustdb.gpg exists;

    # this is a workaround for Debian bug #737128

    gpg --quiet --batch --no-tty --no-options --enable-dsa2 \

	--homedir "$RINGDIR" \

	--import-ownertrust < /dev/null

    # Generate a new key in the key rings

    gpg --quiet --batch --no-tty --no-options --enable-dsa2 \

	--homedir "$RINGDIR" --trust-model always \

	--gen-key "$BATCHFILE"

    rm --force "$BATCHFILE"

    if tty --quiet; then

	echo -n "Finished: "

	date

    fi

    # Backup any old key files

    if cp --backup=numbered --force "$SECKEYFILE" "$SECKEYFILE" \

	2>/dev/null; then

	shred --remove "$SECKEYFILE" 2>/dev/null || :

    fi

    if cp --backup=numbered --force "$PUBKEYFILE" "$PUBKEYFILE" \

	2>/dev/null; then

	rm --force "$PUBKEYFILE"

    fi

    FILECOMMENT="Mandos client key for $KEYNAME"

    if [ "$KEYCOMMENT" != "$KEYCOMMENT_ORIG" ]; then

	FILECOMMENT="$FILECOMMENT ($KEYCOMMENT)"

    fi

    if [ -n "$KEYEMAIL" ]; then

	FILECOMMENT="$FILECOMMENT <$KEYEMAIL>"

    fi

    # Export key from key rings to key files

    gpg --quiet --batch --no-tty --no-options --enable-dsa2 \

	--homedir "$RINGDIR" --armor --export-options export-minimal \

	--comment "$FILECOMMENT" --output "$SECKEYFILE" \

	--export-secret-keys

    gpg --quiet --batch --no-tty --no-options --enable-dsa2 \

	--homedir "$RINGDIR" --armor --export-options export-minimal \

	--comment "$FILECOMMENT" --output "$PUBKEYFILE" --export

fi

if [ "$mode" = password ]; then

    # Make SSH be 0 or 1

    case "$SSH" in

	[Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]) SSH=1;;

	[Nn][Oo]|[Ff][Aa][Ll][Ss][Ee]|*) SSH=0;;

    esac

    if [ $SSH -eq 1 ]; then

	# The -q option is new in OpenSSH 9.8

	for ssh_keyscan_quiet in "-q " ""; do

	    for ssh_keytype in ecdsa-sha2-nistp256 ed25519 rsa; do

		set +e

		ssh_fingerprint="`ssh-keyscan ${ssh_keyscan_quiet}-t $ssh_keytype localhost 2>/dev/null`"

		err=$?

		set -e

		if [ $err -ne 0 ]; then

		    ssh_fingerprint=""

		    continue

		fi

		if [ -n "$ssh_fingerprint" ]; then

		    ssh_fingerprint="${ssh_fingerprint#localhost }"

		    break 2

		fi

	    done

	done

    fi

    # Import key into temporary key rings

    gpg --quiet --batch --no-tty --no-options --enable-dsa2 \

	--homedir "$RINGDIR" --trust-model always --armor \

	--import "$SECKEYFILE"

    gpg --quiet --batch --no-tty --no-options --enable-dsa2 \

	--homedir "$RINGDIR" --trust-model always --armor \

	--import "$PUBKEYFILE"

    # Get fingerprint of key

    FINGERPRINT="`gpg --quiet --batch --no-tty --no-options \

	--enable-dsa2 --homedir "$RINGDIR" --trust-model always \

	--fingerprint --with-colons \

	| sed --quiet \

	--expression='/^fpr:/{s/^fpr:.*:\\([0-9A-Z]*\\):\$/\\1/p;q}'`"

    test -n "$FINGERPRINT"

    if [ -r "$TLS_PUBKEYFILE" ]; then

       KEY_ID="$(certtool --key-id --hash=sha256 \

    		       --infile="$TLS_PUBKEYFILE" 2>/dev/null || :)"

       if [ -z "$KEY_ID" ]; then

	   KEY_ID=$(openssl pkey -pubin -in "$TLS_PUBKEYFILE" \

			    -outform der \

			| openssl sha256 \

			| sed --expression='s/^.*[^[:xdigit:]]//')

       fi

       test -n "$KEY_ID"

    fi

    FILECOMMENT="Encrypted password for a Mandos client"

    while [ ! -s "$SECFILE" ]; do

	if [ -n "$PASSFILE" ]; then

	    cat -- "$PASSFILE"

	else

	    tty --quiet && stty -echo

	    echo -n "Enter passphrase: " >/dev/tty

	    read -r first

	    tty --quiet && echo >&2

	    echo -n "Repeat passphrase: " >/dev/tty

	    read -r second

	    if tty --quiet; then

		echo >&2

		stty echo

	    fi

	    if [ "$first" != "$second" ]; then

		echo "Passphrase mismatch" >&2

		touch "$RINGDIR"/mismatch

	    else

		printf "%s" "$first"

	    fi

	fi | gpg --quiet --batch --no-tty --no-options --enable-dsa2 \

	    --homedir "$RINGDIR" --trust-model always --armor \

	    --encrypt --sign --recipient "$FINGERPRINT" --comment \

	    "$FILECOMMENT" > "$SECFILE"

	if [ -e "$RINGDIR"/mismatch ]; then

	    rm --force "$RINGDIR"/mismatch

	    if tty --quiet; then

		> "$SECFILE"

	    else

		exit 1

	    fi

	fi

    done

    cat <<-EOF

	[$KEYNAME]

	host = $KEYNAME

	EOF

    if [ -n "$KEY_ID" ]; then

	echo "key_id = $KEY_ID"

    fi

    cat <<-EOF

	fingerprint = $FINGERPRINT

	secret =

	EOF

    sed --quiet --expression='

	/^-----BEGIN PGP MESSAGE-----$/,/^-----END PGP MESSAGE-----$/{

	    /^$/,${

		# Remove 24-bit Radix-64 checksum

		s/=....$//

		# Indent four spaces

		/^[^-]/s/^/    /p

	    }

	}' < "$SECFILE"

    if [ -n "$ssh_fingerprint" ]; then

	if [ -n "$ssh_keyscan_quiet" ]; then

	    echo "# Note: if the Mandos server has OpenSSH older than 9.8, the ${ssh_keyscan_quiet}"

	    echo "# option *must* be removed from the 'checker' setting below"

	fi

	echo 'checker = ssh-keyscan '"$ssh_keyscan_quiet"'-t '"$ssh_keytype"' %%(host)s 2>/dev/null | grep --fixed-strings --line-regexp --quiet --regexp=%%(host)s" %(ssh_fingerprint)s"'

	echo "ssh_fingerprint = ${ssh_fingerprint}"

    fi

fi

trap - EXIT

set +e

# Remove the password file, if any

if [ -n "$SECFILE" ]; then

    shred --remove "$SECFILE" 2>/dev/null

fi

# Remove the key rings

shred --remove "$RINGDIR"/sec* 2>/dev/null

rm --recursive --force "$RINGDIR"