Merge commit 'dkg/master'

4 files changed, 400 insertions, 116 deletions

diff --git a/src/common b/src/common
index f6000d3..eb3a083 100644
--- a/src/common
+++ b/src/common
@@ -19,6 +19,9 @@
 SYSCONFIGDIR=${MONKEYSPHERE_SYSCONFIGDIR:-"/etc/monkeysphere"}
 export SYSCONFIGDIR
 
+# monkeysphere version
+VERSION=__VERSION__
+
 ########################################################################
 ### UTILITY FUNCTIONS
 
diff --git a/src/keytrans/pem2openpgp b/src/keytrans/pem2openpgp
new file mode 100755
index 0000000..2fa221d
--- /dev/null
+++ b/src/keytrans/pem2openpgp
@@ -0,0 +1,252 @@
+#!/usr/bin/perl -w -T
+
+# pem2openpgp: take a PEM-encoded RSA private-key on standard input, a
+# User ID as the first argument, and generate an OpenPGP certificate
+# from it.
+
+# Usage:
+
+# pem2openpgp 'ssh://'$(hostname -f) < /etc/ssh/ssh_host_rsa_key | gpg --import
+
+# Authors:
+#  Jameson Rollins <jrollins@finestructure.net>
+#  Daniel Kahn Gillmor <dkg@fifthhorseman.net>
+
+# Started on: 2009-01-07 02:01:19-0500
+
+# License: GPL v3 or later (we may need to adjust this given that this
+# connects to OpenSSL via perl)
+
+use strict;
+use warnings;
+use Crypt::OpenSSL::RSA;
+use Crypt::OpenSSL::Bignum;
+use Digest::SHA1;
+use MIME::Base64;
+
+## make sure all length() and substr() calls use bytes only:
+use bytes;
+
+my $uid = shift;
+
+# FIXME: fail if there is no given user ID; or should we default to
+# hostname_long() from Sys::Hostname::Long ?
+
+# make an old-style packet out of the given packet type and body.
+# old-style  (see RFC 4880 section 4.2)
+sub make_packet {
+  my $type = shift;
+  my $body = shift;
+
+  my $len = length($body);
+
+  my $lenbytes;
+  my $lencode;
+
+  if ($len < 2**8) {
+    $lenbytes = 0;
+    $lencode = 'C';
+  } elsif ($len < 2**16) {
+    $lenbytes = 1;
+    $lencode = 'n';
+  } elsif ($len < 2**31) {
+    ## not testing against full 32 bits because i don't want to deal
+    ## with potential overflow.
+    $lenbytes = 2;
+    $lencode = 'N';
+  } else {
+    ## what the hell do we do here?
+    $lenbytes = 3;
+    $lencode = '';
+  }
+
+  return pack('C'.$lencode, 0x80 + ($type * 4) + $lenbytes, $len).
+    $body;
+}
+
+
+# takes a Crypt::OpenSSL::Bignum, returns it formatted as OpenPGP MPI
+# (RFC 4880 section 3.2)
+sub mpi_pack {
+  my $num = shift;
+
+  my $val = $num->to_bin();
+  my $mpilen = length($val)*8;
+
+# this is a kludgy way to get the number of significant bits in the
+# first byte:
+  my $bitsinfirstbyte = length(sprintf("%b", ord($val)));
+
+  $mpilen -= (8 - $bitsinfirstbyte);
+
+  return pack('n', $mpilen).$val;
+}
+
+# FIXME: genericize this to accept either RSA or DSA keys:
+sub make_rsa_pub_key_body {
+  my $key = shift;
+  my $timestamp = shift;
+
+  my ($n, $e) = $key->get_key_parameters();
+
+  return
+    pack('CN', 4, $timestamp).
+      pack('C', 1). # RSA
+	mpi_pack($n).
+	  mpi_pack($e);
+
+}
+
+# expects an RSA key (public or private) and a timestamp
+sub fingerprint {
+  my $key = shift;
+  my $timestamp = shift;
+
+  my $rsabody = make_rsa_pub_key_body($key, $timestamp);
+
+  return Digest::SHA1::sha1(pack('Cn', 0x99, length($rsabody)).$rsabody);
+}
+
+# FIXME: make tables of relevant identifiers: digest algorithms,
+# ciphers, asymmetric crypto, packet types, subpacket types, signature
+# types.  As these are created, replace the opaque numbers below with
+# semantically-meaningful code.
+
+# see RFC 4880 section 5.2.3.21
+my $usage_flags = { certify => 0x01,
+		    sign => 0x02,
+		    encrypt_comms => 0x04,
+		    encrypt_storage => 0x08,
+		    encrypt => 0x0c, ## both comms and storage
+		    split => 0x10, # the private key is split via secret sharing
+		    authenticate => 0x20,
+		    shared => 0x80, # more than one person holds the entire private key
+		  };
+
+
+# we're just not dealing with newline business right now.  slurp in
+# the whole file.
+undef $/;
+my $buf = <STDIN>;
+
+
+my $rsa = Crypt::OpenSSL::RSA->new_private_key($buf);
+
+$rsa->use_sha1_hash();
+$rsa->use_no_padding();
+
+if (! $rsa->check_key()) {
+  die "key does not check";
+}
+
+my $version = pack('C', 4);
+# strong assertion of identity:
+my $sigtype = pack('C', 0x13);
+# RSA
+my $pubkey_algo = pack('C', 1);
+# SHA1
+my $hash_algo = pack('C', 2);
+
+# FIXME: i'm worried about generating a bazillion new OpenPGP
+# certificates from the same key, which could easily happen if you run
+# this script more than once against the same key.  How can we prevent
+# this?
+
+# could an environment variable (if set) override the current time?
+my $timestamp = time();
+
+my $creation_time_packet = pack('CCN', 5, 2, $timestamp);
+
+
+# FIXME: HARDCODED: what if someone wants to select a different set of
+# usage flags?  For now, we do only authentication.
+my $flags = $usage_flags->{authenticate};
+my $usage_packet = pack('CCC', 2, 27, $flags);
+
+
+# FIXME: HARDCODED: how should we determine how far off to set the
+# expiration date?  default is to expire in 2 days, which is insanely
+# short (but good for testing).
+my $expires_in = 86400*2;
+my $expiration_packet = pack('CCN', 5, 9, $expires_in);
+
+
+# prefer AES-256, AES-192, AES-128, CAST5, 3DES:
+my $pref_sym_algos = pack('CCCCCCC', 6, 11, 9, 8, 7, 3, 2);
+
+# prefer SHA-1, SHA-256, RIPE-MD/160
+my $pref_hash_algos = pack('CCCCC', 4, 21, 2, 8, 3);
+
+# prefer ZLIB, BZip2, ZIP
+my $pref_zip_algos = pack('CCCCC', 4, 22, 2, 3, 1);
+
+# we support the MDC feature:
+my $features = pack('CCC', 2, 30, 1);
+
+# keyserver preference: only owner modify (???):
+my $keyserver_pref = pack('CCC', 2, 23, 0x80);
+
+my $subpackets_to_be_hashed =
+  $creation_time_packet.
+  $usage_packet.
+  $expiration_packet.
+  $pref_sym_algos.
+  $pref_hash_algos.
+  $pref_zip_algos.
+  $features.
+  $keyserver_pref;
+
+my $subpacket_octets = pack('n', length($subpackets_to_be_hashed));
+
+my $sig_data_to_be_hashed =
+  $version.
+  $sigtype.
+  $pubkey_algo.
+  $hash_algo.
+  $subpacket_octets.
+  $subpackets_to_be_hashed;
+
+my $pubkey = make_rsa_pub_key_body($rsa, $timestamp);
+
+#open(KEYFILE, "</home/wt215/gpg-test/key-data");
+my $key_data = make_packet(6, $pubkey);
+
+# take the last 8 bytes of the fingerprint as the keyid:
+my $keyid = substr(fingerprint($rsa, $timestamp), 20 - 8, 8);
+
+# the v4 signature trailer is:
+
+# version number, literal 0xff, and then a 4-byte count of the
+# signature data itself.
+my $trailer = pack('CCN', 4, 0xff, length($sig_data_to_be_hashed));
+
+my $uid_data =
+  pack('CN', 0xb4, length($uid)).
+  $uid;
+
+my $datatosign =
+  $key_data.
+  $uid_data.
+  $sig_data_to_be_hashed.
+  $trailer;
+
+my $data_hash = Digest::SHA1::sha1_hex($datatosign);
+
+
+my $issuer_packet = pack('CCa8', 9, 16, $keyid);
+
+my $sig = Crypt::OpenSSL::Bignum->new_from_bin($rsa->sign($datatosign));
+
+my $sig_body =
+  $sig_data_to_be_hashed.
+  pack('n', length($issuer_packet)).
+  $issuer_packet.
+  pack('n', hex(substr($data_hash, 0, 4))).
+  mpi_pack($sig);
+
+print
+  make_packet(6, $pubkey).
+  make_packet(13, $uid).
+  make_packet(2, $sig_body);
+
+
diff --git a/src/monkeysphere b/src/monkeysphere
index 523ddfe..5444cb0 100755
--- a/src/monkeysphere
+++ b/src/monkeysphere
@@ -45,6 +45,7 @@ subcommands:
    --length (-l) BITS                  key length in bits (2048)
    --expire (-e) EXPIRE                date to expire
  subkey-to-ssh-agent (s)             store authentication subkey in ssh-agent
+ version (v)                         show version number
  help (h,?)                          this help
 
 EOF
@@ -63,15 +64,6 @@ gen_subkey(){
     keyExpire=
 
     # get options
-    TEMP=$(PATH="/usr/local/bin:$PATH" getopt -o l:e: -l length:,expire: -n "$PGRM" -- "$@") || failure "getopt failed!  Does your getopt support GNU-style long options?"
-
-    if [ $? != 0 ] ; then
-	exit 1
-    fi
-
-    # Note the quotes around `$TEMP': they are essential!
-    eval set -- "$TEMP"
-
     while true ; do
 	case "$1" in
 	    -l|--length)
@@ -82,51 +74,69 @@ gen_subkey(){
 		keyExpire="$2"
 		shift 2
 		;;
-	    --)
-		shift
-		;;
-            *)
+	    *)
+		if [ "$(echo "$1" | cut -c 1)" = '-' ] ; then
+		    failure "Unknown option '$1'.
+Type '$PGRM help' for usage."
+		fi
 		break
 		;;
 	esac
     done
 
-    if [ -z "$1" ] ; then
-	# find all secret keys
-	keyID=$(gpg --with-colons --list-secret-keys | grep ^sec | cut -f5 -d: | sort -u)
-	# if multiple sec keys exist, fail
-	if (( $(echo "$keyID" | wc -l) > 1 )) ; then
-	    echo "Multiple secret keys found:"
-	    echo "$keyID"
+    case "$#" in
+	0)
+	    gpgSecOut=$(gpg --quiet --fixed-list-mode --list-secret-keys --with-colons 2>/dev/null | egrep '^sec:')
+	    ;;
+	1)
+	    gpgSecOut=$(gpg --quiet --fixed-list-mode --list-secret-keys --with-colons "$1" | egrep '^sec:') || failure
+	    ;;
+	*)
+	    failure "You must specify only a single primary key ID."
+	    ;;
+    esac
+
+    # check that only a single secret key was found
+    case $(echo "$gpgSecOut" | grep -c '^sec:') in
+	0)
+	    failure "No secret keys found.  Create an OpenPGP key with the following command:
+ gpg --gen-key"
+	    ;;
+	1)
+	    keyID=$(echo "$gpgSecOut" | cut -d: -f5)
+	    ;;
+	*)
+	    echo "Multiple primary secret keys found:"
+	    echo "$gpgSecOut" | cut -d: -f5
 	    failure "Please specify which primary key to use."
+	    ;;
+    esac
+
+    # check that a valid authentication key does not already exist
+    IFS=$'\n'
+    for line in $(gpg --quiet --fixed-list-mode --list-keys --with-colons "$keyID") ; do
+	type=$(echo "$line" | cut -d: -f1)
+	validity=$(echo "$line" | cut -d: -f2)
+	usage=$(echo "$line" | cut -d: -f12)
+
+	# look at keys only
+	if [ "$type" != 'pub' -a "$type" != 'sub' ] ; then
+	    continue
 	fi
-    else
-	keyID="$1"
-    fi
-    if [ -z "$keyID" ] ; then
-	failure "You have no secret key available.  You should create an OpenPGP
-key before joining the monkeysphere. You can do this with:
-   gpg --gen-key"
-    fi
-
-    # get key output, and fail if not found
-    gpgOut=$(gpg --quiet --fixed-list-mode --list-secret-keys --with-colons \
-	"$keyID") || failure
-
-    # fail if multiple sec lines are returned, which means the id
-    # given is not unique
-    if [ $(echo "$gpgOut" | grep -c '^sec:') -gt '1' ] ; then
-	failure "Key ID '$keyID' is not unique."
-    fi
-
-    # prompt if an authentication subkey already exists
-    if echo "$gpgOut" | egrep "^(sec|ssb):" | cut -d: -f 12 | grep -q a ; then
-	echo "An authentication subkey already exists for key '$keyID'."
-	read -p "Are you sure you would like to generate another one? (y/N) " OK; OK=${OK:N}
-	if [ "${OK/y/Y}" != 'Y' ] ; then
-	    failure "aborting."
+	# check for authentication capability
+	if ! check_capability "$usage" 'a' ; then
+	    continue
 	fi
-    fi
+	# if authentication key is valid, prompt to continue
+	if [ "$validity" = 'u' ] ; then
+	    echo "A valid authentication key already exists for primary key '$keyID'."
+	    read -p "Are you sure you would like to generate another one? (y/N) " OK; OK=${OK:N}
+	    if [ "${OK/y/Y}" != 'Y' ] ; then
+		failure "aborting."
+	    fi
+	    break
+	fi
+    done
 
     # set subkey defaults
     # prompt about key expiration if not specified
@@ -151,6 +161,7 @@ EOF
     (umask 077 && mkfifo "$fifoDir/pass")
     echo "$editCommands" | gpg --passphrase-fd 3 3< "$fifoDir/pass" --expert --command-fd 0 --edit-key "$keyID" &
 
+    # FIXME: this needs to fail more gracefully if the passphrase is incorrect
     passphrase_prompt  "Please enter your passphrase for $keyID: " "$fifoDir/pass"
 
     rm -rf "$fifoDir"
@@ -373,6 +384,10 @@ case $COMMAND in
 	subkey_to_ssh_agent "$@"
 	;;
 
+    'version'|'v')
+	echo "$VERSION"
+	;;
+
     '--help'|'help'|'-h'|'h'|'?')
         usage
         ;;
diff --git a/src/monkeysphere-server b/src/monkeysphere-server
index c4f6985..ba3fa8d 100755
--- a/src/monkeysphere-server
+++ b/src/monkeysphere-server
@@ -66,6 +66,7 @@ subcommands:
 
  gpg-authentication-cmd CMD          gnupg-authentication command
 
+ version (v)                         show version number
  help (h,?)                          this help
 
 EOF
@@ -117,40 +118,59 @@ gpg_authentication() {
     su_monkeysphere_user "gpg $@"
 }
 
-# function to check for host secret keys
-# fails if host sec key exists, exits true otherwise
-check_host_keyring() {
-    if ! gpg_host --list-secret-keys --fingerprint \
-	--with-colons --fixed-list-mode 2>/dev/null | grep -q '^sec:' ; then
+# check if user is root
+is_root() {
+    [ $(id -u 2>/dev/null) = '0' ]
+}
 
-	failure "You don't appear to have a Monkeysphere host key on this server.  Please run 'monkeysphere-server gen-key' first."
-    fi
+# check that user is root, for functions that require root access
+check_user() {
+    is_root || failure "You must be root to run this command."
 }
 
 # output just key fingerprint
 fingerprint_server_key() {
+    # set the pipefail option so functions fails if can't read sec key
+    set -o pipefail
+
     gpg_host --list-secret-keys --fingerprint \
 	--with-colons --fixed-list-mode 2> /dev/null | \
-	grep '^fpr:' | head -1 | cut -d: -f10
+	grep '^fpr:' | head -1 | cut -d: -f10 2>/dev/null
+}
+
+# function to check for host secret key
+check_host_keyring() {
+    fingerprint_server_key >/dev/null \
+	|| failure "You don't appear to have a Monkeysphere host key on this server.  Please run 'monkeysphere-server gen-key' first."
 }
 
 # output key information
 show_server_key() {
-    local fingerprint
-    local tmpkey
+    local fingerprintPGP
+    local fingerprintSSH
+    local ret=0
 
-    fingerprint=$(fingerprint_server_key)
-    gpg_authentication "--fingerprint --list-key --list-options show-unusable-uids $fingerprint"
-
-    # do some crazy "Here Strings" redirection to get the key to
-    # ssh-keygen, since it doesn't read from stdin cleanly
-    echo -n "ssh fingerprint: "
-    ssh-keygen -l -f /dev/stdin \
-	<<<$(gpg_authentication "--export $fingerprint" | \
-	openpgp2ssh "$fingerprint" 2>/dev/null) | \
-	awk '{ print $1, $2, $4 }'
-    echo -n "OpenPGP fingerprint: "
-    echo "$fingerprint"
+    # FIXME: you shouldn't have to be root to see the host key fingerprint
+    if is_root ; then
+	check_host_keyring
+	fingerprintPGP=$(fingerprint_server_key)
+	gpg_authentication "--fingerprint --list-key --list-options show-unusable-uids $fingerprintPGP" 2>/dev/null
+	echo "OpenPGP fingerprint: $fingerprintPGP"
+    else
+	log info "You must be root to see host OpenPGP fingerprint."
+	ret='1'
+    fi
+
+    if [ -f "${SYSDATADIR}/ssh_host_rsa_key.pub" ] ; then
+	fingerprintSSH=$(ssh-keygen -l -f "${SYSDATADIR}/ssh_host_rsa_key.pub" | \
+	    awk '{ print $1, $2, $4 }')
+	echo "ssh fingerprint: $fingerprintSSH"
+    else
+	log info "SSH host key not found."
+	ret='1'
+    fi
+
+    return $ret
 }
 
 # update authorized_keys for users
@@ -311,15 +331,6 @@ gen_key() {
     revoker=
 
     # get options
-    TEMP=$(PATH="/usr/local/bin:$PATH" getopt -o e:l:r -l expire:,length:,revoker: -n "$PGRM" -- "$@") || failure "getopt failed!  Does your getopt support GNU-style long options?"
-
-    if [ $? != 0 ] ; then
-	exit 1
-    fi
-
-    # Note the quotes around `$TEMP': they are essential!
-    eval set -- "$TEMP"
-
     while true ; do
 	case "$1" in
 	    -l|--length)
@@ -334,10 +345,11 @@ gen_key() {
 		revoker="$2"
 		shift 2
 		;;
-	    --)
-		shift
-		;;
-            *)
+	    *)
+		if [ "$(echo "$1" | cut -c 1)" = '-' ] ; then
+		    failure "Unknown option '$1'.
+Type '$PGRM help' for usage."
+		fi
 		break
 		;;
 	esac
@@ -346,33 +358,29 @@ gen_key() {
     hostName=${1:-$(hostname -f)}
     userID="ssh://${hostName}"
 
-    # check for presense of key with user ID
+    # check for presense of secret key
     # FIXME: is this the proper test to be doing here?
-    if gpg_host --list-key ="$userID" > /dev/null 2>&1 ; then
-	failure "Key for '$userID' already exists"
-    fi
+    fingerprint_server_key >/dev/null \
+	&& failure "A key for this host already exists."
 
     # prompt about key expiration if not specified
     keyExpire=$(get_gpg_expiration "$keyExpire")
 
     # set key parameters
-    keyParameters=$(cat <<EOF
-Key-Type: $keyType
+    keyParameters=\
+"Key-Type: $keyType
 Key-Length: $keyLength
 Key-Usage: $keyUsage
 Name-Real: $userID
-Expire-Date: $keyExpire
-EOF
-)
+Expire-Date: $keyExpire"
 
     # add the revoker field if specified
     # FIXME: the "1:" below assumes that $REVOKER's key is an RSA key.
     # FIXME: key is marked "sensitive"?  is this appropriate?
     if [ "$revoker" ] ; then
-	keyParameters="${keyParameters}"$(cat <<EOF
-Revoker: 1:$revoker sensitive
-EOF
-)
+	keyParameters=\
+"${keyParameters}
+Revoker: 1:${revoker} sensitive"
     fi
 
     echo "The following key parameters will be used for the host private key:"
@@ -384,19 +392,16 @@ EOF
     fi
 
     # add commit command
-    keyParameters="${keyParameters}"$(cat <<EOF
+    # must include blank line!
+    keyParameters=\
+"${keyParameters}
 
 %commit
-%echo done
-EOF
-)
+%echo done"
 
     log verbose "generating server key..."
     echo "$keyParameters" | gpg_host --batch --gen-key
 
-    # output the server fingerprint
-    fingerprint_server_key "=${userID}"
-
     # find the key fingerprint of the newly generated key
     fingerprint=$(fingerprint_server_key)
 
@@ -415,6 +420,9 @@ EOF
     log info "SSH host public key output to file: ${SYSDATADIR}/ssh_host_rsa_key.pub"
     gpg_authentication "--export-options export-minimal --armor --export 0x${fingerprint}\!" > "${SYSDATADIR}/ssh_host_rsa_key.pub.gpg"
     log info "SSH host public key in OpenPGP form: ${SYSDATADIR}/ssh_host_rsa_key.pub.gpg"
+
+    # show info about new key
+    show_server_key
 }
 
 # extend the lifetime of a host key:
@@ -478,7 +486,7 @@ $userID
 
 save
 EOF
-	)
+)
 
     # execute edit-key script
     if echo "$adduidCommand" | \
@@ -778,15 +786,6 @@ add_certifier() {
     depth=1
 
     # get options
-    TEMP=$(PATH="/usr/local/bin:$PATH" getopt -o n:t:d: -l domain:,trust:,depth: -n "$PGRM" -- "$@") || failure "getopt failed!  Does your getopt support GNU-style long options?"
-
-    if [ $? != 0 ] ; then
-	exit 1
-    fi
-
-    # Note the quotes around `$TEMP': they are essential!
-    eval set -- "$TEMP"
-
     while true ; do
 	case "$1" in
 	    -n|--domain)
@@ -801,10 +800,11 @@ add_certifier() {
 		depth="$2"
 		shift 2
 		;;
-	    --)
-		shift
-		;;
-            *)
+	    *)
+		if [ "$(echo "$1" | cut -c 1)" = '-' ] ; then
+		    failure "Unknown option '$1'.
+Type '$PGRM help' for usage."
+		fi
 		break
 		;;
 	esac
@@ -1001,62 +1001,76 @@ shift
 
 case $COMMAND in
     'update-users'|'update-user'|'u')
+	check_user
 	check_host_keyring
 	update_users "$@"
 	;;
 
     'gen-key'|'g')
+	check_user
 	gen_key "$@"
 	;;
 
     'extend-key'|'e')
+	check_user
 	check_host_keyring
 	extend_key "$@"
 	;;
 
     'add-hostname'|'add-name'|'n+')
+	check_user
 	check_host_keyring
 	add_hostname "$@"
 	;;
 
     'revoke-hostname'|'revoke-name'|'n-')
+	check_user
 	check_host_keyring
 	revoke_hostname "$@"
 	;;
 
     'show-key'|'show'|'s')
-	check_host_keyring
 	show_server_key
 	;;
 
     'publish-key'|'publish'|'p')
+	check_user
 	check_host_keyring
 	publish_server_key
 	;;
 
     'diagnostics'|'d')
+	check_user
 	diagnostics
 	;;
 
     'add-identity-certifier'|'add-id-certifier'|'add-certifier'|'c+')
+	check_user
 	check_host_keyring
 	add_certifier "$@"
 	;;
 
     'remove-identity-certifier'|'remove-id-certifier'|'remove-certifier'|'c-')
+	check_user
 	check_host_keyring
 	remove_certifier "$@"
 	;;
 
     'list-identity-certifiers'|'list-id-certifiers'|'list-certifiers'|'list-certifier'|'c')
+	check_user
 	check_host_keyring
 	list_certifiers "$@"
 	;;
 
     'gpg-authentication-cmd')
+	check_user
 	gpg_authentication_cmd "$@"
 	;;
 
+    'version'|'v')
+	echo "$VERSION"
+	;;
+
     '--help'|'help'|'-h'|'h'|'?')
         usage
         ;;