};
+# see RFC 4880 section 5.2.3.23
+my $revocation_reasons = { no_reason_specified => 0,
+ key_superseded => 1,
+ key_compromised => 2,
+ key_retired => 3,
+ user_id_no_longer_valid => 32,
+ };
+
# see RFC 4880 section 5.2.3.1
my $subpacket_types = { sig_creation_time => 2,
sig_expiration_time => 3,
# FIXME: handle DSA keys as well!
-sub pem2openpgp {
+sub makeselfsig {
my $rsa = shift;
my $uid = shift;
my $args = shift;
- $rsa->use_sha256_hash();
-
- # see page 22 of RFC 4880 for why i think this is the right padding
- # choice to use:
- $rsa->use_pkcs1_padding();
-
- if (! $rsa->check_key()) {
- die "key does not check";
- }
-
# strong assertion of identity is the default (for a self-sig):
- my $certtype = $sig_types->{positive_certification};
- if (defined $args->{certification_type}) {
- $certtype = $args->{certification_type} + 0;
+ if (! defined $args->{certification_type}) {
+ $args->{certification_type} = $sig_types->{positive_certification};
}
- my $version = pack('C', 4);
- my $sigtype = pack('C', $certtype);
- # RSA
- my $pubkey_algo = pack('C', $asym_algos->{rsa});
- # SHA256
- my $hash_algo = pack('C', $digests->{sha256});
-
- # 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 (because the
- # timestamps will differ). How can we prevent this?
-
- # this argument (if set) overrides the current time, to
- # be able to create a standard key. If we read the key from a file
- # instead of stdin, should we use the creation time on the file?
- my $sig_timestamp = 0;
- if (defined $args->{sig_timestamp}) {
- $sig_timestamp = ($args->{sig_timestamp} + 0);
- } else {
- $sig_timestamp = time();
- }
- my $key_timestamp = $sig_timestamp;
- if (defined $args->{key_timestamp}) {
- $key_timestamp = ($args->{key_timestamp} + 0);
- }
- if ($key_timestamp > $sig_timestamp) {
- die "key timestamp must not be later than signature timestamp";
+ if (! defined $args->{sig_timestamp}) {
+ $args->{sig_timestamp} = time();
}
+ my $key_timestamp = $args->{key_timestamp} + 0;
- my $creation_time_packet = pack('CCN', 5, $subpacket_types->{sig_creation_time}, $sig_timestamp);
-
+ # generate and aggregate subpackets:
+ # key usage flags:
my $flags = 0;
if (! defined $args->{usage_flags}) {
$flags = $usage_flags->{certify};
$flags |= $usage_flags->{$f};
}
}
-
- my $usage_packet = pack('CCC', 2, $subpacket_types->{usage_flags}, $flags);
-
+ my $usage_subpacket = pack('CCC', 2, $subpacket_types->{usage_flags}, $flags);
# how should we determine how far off to set the expiration date?
# default is no expiration. Specify the timestamp in seconds from the
# key creation.
- my $expiration_packet = '';
+ my $expiration_subpacket = '';
if (defined $args->{expiration}) {
my $expires_in = $args->{expiration} + 0;
- $expiration_packet = pack('CCN', 5, $subpacket_types->{key_expiration_time}, $expires_in);
+ $expiration_subpacket = pack('CCN', 5, $subpacket_types->{key_expiration_time}, $expires_in);
}
my $keyserver_pref = pack('CCC', 2, $subpacket_types->{keyserver_prefs},
$keyserver_prefs->{nomodify});
- my $subpackets_to_be_hashed =
- $creation_time_packet.
- $usage_packet.
- $expiration_packet.
+
+ $args->{hashed_subpackets} =
+ $usage_subpacket.
+ $expiration_subpacket.
$pref_sym_algos.
$pref_hash_algos.
$pref_zip_algos.
$feature_subpacket.
$keyserver_pref;
- my $subpacket_octets = pack('n', length($subpackets_to_be_hashed));
+ return gensig($rsa, $uid, $args);
+}
+
+# FIXME: handle non-RSA keys
+
+# FIXME: this currently only makes self-sigs -- we should parameterize
+# it to make certifications over keys other than the issuer.
+sub gensig {
+ my $rsa = shift;
+ my $uid = shift;
+ my $args = shift;
+
+ # FIXME: allow signature creation using digests other than SHA256
+ $rsa->use_sha256_hash();
+
+ # see page 22 of RFC 4880 for why i think this is the right padding
+ # choice to use:
+ $rsa->use_pkcs1_padding();
+
+ if (! $rsa->check_key()) {
+ die "key does not check\n";
+ }
+
+ my $certtype = $args->{certification_type} + 0;
+
+ my $version = pack('C', 4);
+ my $sigtype = pack('C', $certtype);
+ # RSA
+ my $pubkey_algo = pack('C', $asym_algos->{rsa});
+ # SHA256 FIXME: allow signature creation using digests other than SHA256
+ my $hash_algo = pack('C', $digests->{sha256});
+
+ # 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 (because the
+ # timestamps will differ). How can we prevent this?
+
+ # this argument (if set) overrides the current time, to
+ # be able to create a standard key. If we read the key from a file
+ # instead of stdin, should we use the creation time on the file?
+ my $sig_timestamp = ($args->{sig_timestamp} + 0);
+ my $key_timestamp = ($args->{key_timestamp} + 0);
+
+ if ($key_timestamp > $sig_timestamp) {
+ die "key timestamp must not be later than signature timestamp\n";
+ }
+
+ my $creation_time_packet = pack('CCN', 5, $subpacket_types->{sig_creation_time}, $sig_timestamp);
+
+ my $hashed_subs = $creation_time_packet.$args->{hashed_subpackets};
+
+ my $subpacket_octets = pack('n', length($hashed_subs));
my $sig_data_to_be_hashed =
$version.
$pubkey_algo.
$hash_algo.
$subpacket_octets.
- $subpackets_to_be_hashed;
+ $hashed_subs;
my $pubkey = make_rsa_pub_key_body($rsa, $key_timestamp);
- my $seckey = make_rsa_sec_key_body($rsa, $key_timestamp);
# this is for signing. it needs to be an old-style header with a
# 2-packet octet count.
$sig_data_to_be_hashed.
$trailer;
+ # FIXME: handle signatures over digests other than SHA256:
my $data_hash = Digest::SHA::sha256_hex($datatosign);
my $issuer_packet = pack('CCa8', 9, $subpacket_types->{issuer}, $keyid);
pack('n', hex(substr($data_hash, 0, 4))).
mpi_pack($sig);
- return
- make_packet($packet_types->{seckey}, $seckey).
- make_packet($packet_types->{uid}, $uid).
- make_packet($packet_types->{sig}, $sig_body);
+ return make_packet($packet_types->{sig}, $sig_body);
}
# FIXME: switch to passing the whole packet as the arg, instead of the
# input stream.
+# FIXME: think about native perl representation of the packets instead.
+
+# Put a user ID into the $data
+sub finduid {
+ my $data = shift;
+ my $instr = shift;
+ my $tag = shift;
+ my $packetlen = shift;
+
+ my $dummy;
+ ($tag == $packet_types->{uid}) or die "This should not be called on anything but a User ID packet\n";
+
+ read($instr, $dummy, $packetlen);
+ $data->{uid}->{$dummy} = {};
+ $data->{current}->{uid} = $dummy;
+}
+
+
+# find signatures associated with the given fingerprint and user ID.
+sub findsig {
+ my $data = shift;
+ my $instr = shift;
+ my $tag = shift;
+ my $packetlen = shift;
+
+ ($tag == $packet_types->{sig}) or die "No calling findsig on anything other than a signature packet.\n";
+
+ my $dummy;
+ my $readbytes = 0;
+
+ read($instr, $dummy, $packetlen - $readbytes) or die "Could not read in this packet.\n";
+
+ if ((! defined $data->{key}) ||
+ (! defined $data->{uid}) ||
+ (! defined $data->{uid}->{$data->{target}->{uid}})) {
+ # the user ID we are looking for has not been found yet.
+ return;
+ }
+
+ # FIXME: if we get two primary keys on stdin, both with the same
+ # targetd user ID, we'll store signatures from both keys, which is
+ # probably wrong.
+
+ # the current ID is not what we're looking for:
+ return if ($data->{current}->{uid} ne $data->{target}->{uid});
+
+ # just storing the raw signatures for the moment:
+ push @{$data->{sigs}}, make_packet($packet_types->{sig}, $dummy);
+ return;
+
+}
+
# given an input stream and data, store the found key in data and
# consume the rest of the stream corresponding to the packet.
# data contains: (fpr: fingerprint to find, key: current best guess at key)
$foundfprstr = sprintf("%040s", $foundfprstr);
# is this a match?
- if ((!defined($data->{fpr})) ||
- (substr($foundfprstr, -1 * length($data->{fpr})) eq $data->{fpr})) {
+ if ((!defined($data->{target}->{fpr})) ||
+ (substr($foundfprstr, -1 * length($data->{target}->{fpr})) eq $data->{target}->{fpr})) {
if (defined($data->{key})) {
die "Found two matching keys.\n";
}
- $data->{key} = $pubkey;
+ $data->{key} = { 'rsa' => $pubkey,
+ 'timestamp' => $key_timestamp };
}
if ($tag != $packet_types->{seckey} &&
}
return;
}
- if (!defined($data->{key})) {
+ if (!defined($data->{key})) {
# we don't think the public part of this key matches
if ($readbytes < $packetlen) {
read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
# FIXME: compare with the checksum! how? the data is
# gone into the Crypt::OpenSSL::Bignum
- $data->{key} = Crypt::OpenSSL::RSA->new_key_from_parameters($modulus,
- $exponent,
- $d,
- $p,
- $q);
+ $data->{key}->{rsa} = Crypt::OpenSSL::RSA->new_key_from_parameters($modulus,
+ $exponent,
+ $d,
+ $p,
+ $q);
- $data->{key}->check_key() or die "Secret key is not a valid RSA key.\n";
+ $data->{key}->{rsa}->check_key() or die "Secret key is not a valid RSA key.\n";
if ($readbytes < $packetlen) {
read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
}
}
-sub openpgp2ssh {
+sub openpgp2rsa {
my $instr = shift;
my $fpr = shift;
$fpr = uc($fpr);
}
- my $data = { 'fpr' => $fpr};
+ my $data = { target => { fpr => $fpr,
+ },
+ };
my $subs = { $packet_types->{pubkey} => \&findkey,
$packet_types->{pub_subkey} => \&findkey,
$packet_types->{seckey} => \&findkey,
packetwalk($instr, $subs, $data);
- return $data->{key};
+ return $data->{key}->{rsa};
+}
+
+sub adduserid {
+ my $instr = shift;
+ my $fpr = shift;
+ my $uid = shift;
+ my $args = shift;
+
+ if ((! defined $fpr) ||
+ (length($fpr) < 8)) {
+ die "We need at least 8 hex digits of fingerprint.\n";
+ }
+
+ $fpr = uc($fpr);
+
+ if (! defined $uid) {
+ die "No User ID defined.\n";
+ }
+
+ my $data = { target => { fpr => $fpr,
+ uid => $uid,
+ },
+ };
+ my $subs = { $packet_types->{seckey} => \&findkey,
+ $packet_types->{uid} => \&finduid,
+ $packet_types->{sig} => \&findsig,
+ };
+
+ packetwalk($instr, $subs, $data);
+
+ if ((! defined $data->{key}) ||
+ (! defined $data->{key}->{rsa}) ||
+ (! defined $data->{key}->{timestamp})) {
+ die "The key requested was not found.\n"
+ }
+
+ if (defined $data->{uid}->{$uid}) {
+ die "The requested User ID '$uid' is already associated with this key.\n";
+ }
+ $args->{key_timestamp} = $data->{key}->{timestamp};
+
+ return
+ make_packet($packet_types->{pubkey}, make_rsa_pub_key_body($data->{key}->{rsa}, $data->{key}->{timestamp})).
+ make_packet($packet_types->{uid}, $uid).
+ makeselfsig($data->{key}->{rsa},
+ $uid,
+ $args);
+
}
+
+sub revokeuserid {
+ my $instr = shift;
+ my $fpr = shift;
+ my $uid = shift;
+ my $sigtime = shift;
+
+ if ((! defined $fpr) ||
+ (length($fpr) < 8)) {
+ die "We need at least 8 hex digits of fingerprint.\n";
+ }
+
+ $fpr = uc($fpr);
+
+ if (! defined $uid) {
+ die "No User ID defined.\n";
+ }
+
+ my $data = { target => { fpr => $fpr,
+ uid => $uid,
+ },
+ };
+ my $subs = { $packet_types->{seckey} => \&findkey,
+ $packet_types->{uid} => \&finduid,
+ $packet_types->{sig} => \&findsig,
+ };
+
+ packetwalk($instr, $subs, $data);
+
+ if ((! defined $data->{uid}) ||
+ (! defined $data->{uid}->{$uid})) {
+ die "The User ID \"$uid\" is not associated with this key";
+ }
+
+ if ((! defined $data->{key}) ||
+ (! defined $data->{key}->{rsa}) ||
+ (! defined $data->{key}->{timestamp})) {
+ die "The key requested was not found."
+ }
+
+ my $revocation_reason = 'No longer using this hostname';
+ if (defined $data->{revocation_reason}) {
+ $revocation_reason = $data->{revocation_reason};
+ }
+
+ my $rev_reason_subpkt = prefixsubpacket(pack('CC',
+ $subpacket_types->{revocation_reason},
+ $revocation_reasons->{user_id_no_longer_valid}).
+ $revocation_reason);
+
+ if (! defined $sigtime) {
+ $sigtime = time();
+ }
+ # what does a signature like this look like?
+ my $args = { key_timestamp => $data->{key}->{timestamp},
+ sig_timestamp => $sigtime,
+ certification_type => $sig_types->{certification_revocation},
+ hashed_subpackets => $rev_reason_subpkt,
+ };
+
+ return
+ make_packet($packet_types->{pubkey}, make_rsa_pub_key_body($data->{key}->{rsa}, $data->{key}->{timestamp})).
+ make_packet($packet_types->{uid}, $uid).
+ join('', @{$data->{sigs}}).
+ gensig($data->{key}->{rsa}, $uid, $args);
+}
+
+
+# see 5.2.3.1 for tips on how to calculate the length of a subpacket:
+sub prefixsubpacket {
+ my $subpacket = shift;
+
+ my $len = length($subpacket);
+ my $prefix;
+ use bytes;
+ if ($len < 192) {
+ # one byte:
+ $prefix = pack('C', $len);
+ } elsif ($len < 16576) {
+ my $in = $len - 192;
+ my $second = $in%256;
+ my $first = ($in - $second)>>8;
+ $prefix = pack('CC', $first + 192, $second)
+ } else {
+ $prefix = pack('CN', 255, $len);
+ }
+ return $prefix.$subpacket;
+}
+
+
+
sub packetwalk {
my $instr = shift;
my $subs = shift;
$rsa = Crypt::OpenSSL::RSA->new_private_key($stdin);
}
- print pem2openpgp($rsa,
+ my $key_timestamp = $ENV{PEM2OPENPGP_KEY_TIMESTAMP};
+ my $sig_timestamp = $ENV{PEM2OPENPGP_TIMESTAMP};
+ $sig_timestamp = time() if (!defined $sig_timestamp);
+ $key_timestamp = $sig_timestamp if (!defined $key_timestamp);
+
+ print
+ make_packet($packet_types->{seckey}, make_rsa_sec_key_body($rsa, $key_timestamp)).
+ make_packet($packet_types->{uid}, $uid).
+ makeselfsig($rsa,
$uid,
- { sig_timestamp => $ENV{PEM2OPENPGP_TIMESTAMP},
- key_timestamp => $ENV{PEM2OPENPGP_KEY_TIMESTAMP},
+ { sig_timestamp => $sig_timestamp,
+ key_timestamp => $key_timestamp,
expiration => $ENV{PEM2OPENPGP_EXPIRATION},
usage_flags => $ENV{PEM2OPENPGP_USAGE_FLAGS},
}
my $instream;
open($instream,'-');
binmode($instream, ":bytes");
- my $key = openpgp2ssh($instream, $fpr);
+ my $key = openpgp2rsa($instream, $fpr);
if (defined($key)) {
if ($key->is_private()) {
print $key->get_private_key_string();
die "No matching key found.\n";
}
}
+ elsif (/^keytrans$/) {
+ # subcommands when keytrans is invoked directly are UNSUPPORTED,
+ # UNDOCUMENTED, and WILL NOT BE MAINTAINED.
+ my $subcommand = shift;
+ for ($subcommand) {
+ if (/^revokeuserid$/) {
+ my $fpr = shift;
+ my $uid = shift;
+ my $instream;
+ open($instream,'-');
+ binmode($instream, ":bytes");
+
+ my $revcert = revokeuserid($instream, $fpr, $uid, $ENV{PEM2OPENPGP_TIMESTAMP});
+
+ print $revcert;
+ } elsif (/^adduserid$/) {
+ my $fpr = shift;
+ my $uid = shift;
+ my $instream;
+ open($instream,'-');
+ binmode($instream, ":bytes");
+ my $newuid = adduserid($instream, $fpr, $uid,
+ { sig_timestamp => $ENV{PEM2OPENPGP_TIMESTAMP},
+ expiration => $ENV{PEM2OPENPGP_EXPIRATION},
+ usage_flags => $ENV{PEM2OPENPGP_USAGE_FLAGS},
+ });
+
+ print $newuid;
+ } else {
+ die "Unrecognized subcommand. keytrans subcommands are not a stable interface!\n";
+ }
+ }
+ }
else {
die "Unrecognized keytrans call.\n";
}
projects / monkeysphere.git / blobdiff