3 # keytrans: this is an RSA key translation utility; it is capable of
4 # transforming RSA keys (both public keys and secret keys) between
5 # several popular representations, including OpenPGP, PEM-encoded
6 # PKCS#1 DER, and OpenSSH-style public key lines.
8 # How it behaves depends on the name under which it is invoked. The
9 # two implementations currently are: pem2openpgp and openpgp2ssh.
13 # pem2openpgp: take a PEM-encoded RSA private-key on standard input, a
14 # User ID as the first argument, and generate an OpenPGP secret key
15 # and certificate from it.
17 # WARNING: the secret key material *will* appear on stdout (albeit in
18 # OpenPGP form) -- if you redirect stdout to a file, make sure the
19 # permissions on that file are appropriately locked down!
23 # pem2openpgp 'ssh://'$(hostname -f) < /etc/ssh/ssh_host_rsa_key | gpg --import
28 # openpgp2ssh: take a stream of OpenPGP packets containing public or
29 # secret key material on standard input, and a Key ID (or fingerprint)
30 # as the first argument. Find the matching key in the input stream,
31 # and emit it on stdout in an OpenSSH-compatible format. If the input
32 # key is an OpenPGP public key (either primary or subkey), the output
33 # will be an OpenSSH single-line public key. If the input key is an
34 # OpenPGP secret key, the output will be a PEM-encoded RSA key.
38 # gpg --export-secret-subkeys --export-options export-reset-subkey-passwd $KEYID | \
39 # openpgp2ssh $KEYID | ssh-add /dev/stdin
43 # Jameson Rollins <jrollins@finestructure.net>
44 # Daniel Kahn Gillmor <dkg@fifthhorseman.net>
46 # Started on: 2009-01-07 02:01:19-0500
48 # License: GPL v3 or later (we may need to adjust this given that this
49 # connects to OpenSSL via perl)
54 use Crypt::OpenSSL::RSA;
55 use Crypt::OpenSSL::Bignum;
56 use Crypt::OpenSSL::Bignum::CTX;
61 ## make sure all length() and substr() calls use bytes only:
64 my $old_format_packet_lengths = { one => 0,
70 # see RFC 4880 section 9.1 (ignoring deprecated algorithms for now)
71 my $asym_algos = { rsa => 1,
76 # see RFC 4880 section 9.2
77 my $ciphers = { plaintext => 0,
88 # see RFC 4880 section 9.3
89 my $zips = { uncompressed => 0,
95 # see RFC 4880 section 9.4
96 my $digests = { md5 => 1,
105 # see RFC 4880 section 5.2.3.21
106 my $usage_flags = { certify => 0x01,
108 encrypt_comms => 0x04,
109 encrypt_storage => 0x08,
110 encrypt => 0x0c, ## both comms and storage
111 split => 0x10, # the private key is split via secret sharing
112 authenticate => 0x20,
113 shared => 0x80, # more than one person holds the entire private key
116 # see RFC 4880 section 4.3
117 my $packet_types = { pubkey_enc_session => 1,
119 symkey_enc_session => 3,
124 compressed_data => 8,
132 symenc_w_integrity => 18,
136 # see RFC 4880 section 5.2.1
137 my $sig_types = { binary_doc => 0x00,
140 generic_certification => 0x10,
141 persona_certification => 0x11,
142 casual_certification => 0x12,
143 positive_certification => 0x13,
144 subkey_binding => 0x18,
145 primary_key_binding => 0x19,
146 key_signature => 0x1f,
147 key_revocation => 0x20,
148 subkey_revocation => 0x28,
149 certification_revocation => 0x30,
155 # see RFC 4880 section 5.2.3.23
156 my $revocation_reasons = { no_reason_specified => 0,
158 key_compromised => 2,
160 user_id_no_longer_valid => 32,
163 # see RFC 4880 section 5.2.3.1
164 my $subpacket_types = { sig_creation_time => 2,
165 sig_expiration_time => 3,
170 key_expiration_time => 9,
171 preferred_cipher => 11,
172 revocation_key => 12,
175 preferred_digest => 21,
176 preferred_compression => 22,
177 keyserver_prefs => 23,
178 preferred_keyserver => 24,
183 revocation_reason => 29,
185 signature_target => 31,
186 embedded_signature => 32,
189 # bitstring (see RFC 4880 section 5.2.3.24)
190 my $features = { mdc => 0x01
193 # bitstring (see RFC 4880 5.2.3.17)
194 my $keyserver_prefs = { nomodify => 0x80
197 ###### end lookup tables ######
199 # FIXME: if we want to be able to interpret openpgp data as well as
200 # produce it, we need to produce key/value-swapped lookup tables as well.
203 ########### Math/Utility Functions ##############
206 # see the bottom of page 44 of RFC 4880 (http://tools.ietf.org/html/rfc4880#page-44)
207 sub simple_checksum {
210 return unpack("%16C*",$bytes);
213 # calculate the multiplicative inverse of a mod b this is euclid's
214 # extended algorithm. For more information see:
215 # http://en.wikipedia.org/wiki/Extended_Euclidean_algorithm the
216 # arguments here should be Crypt::OpenSSL::Bignum objects. $a should
217 # be the larger of the two values, and the two values should be
220 sub modular_multi_inverse {
225 my $origdivisor = $b->copy();
227 my $ctx = Crypt::OpenSSL::Bignum::CTX->new();
228 my $x = Crypt::OpenSSL::Bignum->zero();
229 my $y = Crypt::OpenSSL::Bignum->one();
230 my $lastx = Crypt::OpenSSL::Bignum->one();
231 my $lasty = Crypt::OpenSSL::Bignum->zero();
236 while (! $b->is_zero()) {
237 my ($quotient, $remainder) = $a->div($b, $ctx);
243 $x = $lastx->sub($quotient->mul($x, $ctx));
247 $y = $lasty->sub($quotient->mul($y, $ctx));
252 die "did this math wrong.\n";
255 # let's make sure that we return a positive value because RFC 4880,
256 # section 3.2 only allows unsigned values:
258 ($finalquotient, $finalremainder) = $lastx->add($origdivisor)->div($origdivisor, $ctx);
260 return $finalremainder;
264 ############ OpenPGP formatting functions ############
266 # make an old-style packet out of the given packet type and body.
267 # old-style (see RFC 4880 section 4.2)
273 my $len = length($body);
274 my $pseudolen = $len;
276 # if the caller wants to use at least N octets of packet length,
277 # pretend that we're using that many.
278 if (defined $options && defined $options->{'packet_length'}) {
279 $pseudolen = 2**($options->{'packet_length'} * 8) - 1;
281 if ($pseudolen < $len) {
288 if ($pseudolen < 2**8) {
289 $lenbytes = $old_format_packet_lengths->{one};
291 } elsif ($pseudolen < 2**16) {
292 $lenbytes = $old_format_packet_lengths->{two};
294 } elsif ($pseudolen < 2**31) {
295 ## not testing against full 32 bits because i don't want to deal
296 ## with potential overflow.
297 $lenbytes = $old_format_packet_lengths->{four};
300 ## what the hell do we do here?
301 $lenbytes = $old_format_packet_lengths->{indeterminate};
305 return pack('C'.$lencode, 0x80 + ($type * 4) + $lenbytes, $len).
310 # takes a Crypt::OpenSSL::Bignum, returns it formatted as OpenPGP MPI
311 # (RFC 4880 section 3.2)
315 my $val = $num->to_bin();
316 my $mpilen = length($val)*8;
318 # this is a kludgy way to get the number of significant bits in the
320 my $bitsinfirstbyte = length(sprintf("%b", ord($val)));
322 $mpilen -= (8 - $bitsinfirstbyte);
324 return pack('n', $mpilen).$val;
327 # takes a Crypt::OpenSSL::Bignum, returns an MPI packed in preparation
328 # for an OpenSSH-style public key format. see:
329 # http://marc.info/?l=openssh-unix-dev&m=121866301718839&w=2
330 sub openssh_mpi_pack {
333 my $val = $num->to_bin();
334 my $mpilen = length($val);
336 my $ret = pack('N', $mpilen);
338 # if the first bit of the leading byte is high, we should include a
340 if (ord($val) & 0x80) {
341 $ret = pack('NC', $mpilen+1, 0);
347 sub openssh_pubkey_pack {
350 my ($modulus, $exponent) = $key->get_key_parameters();
352 return openssh_mpi_pack(Crypt::OpenSSL::Bignum->new_from_bin("ssh-rsa")).
353 openssh_mpi_pack($exponent).
354 openssh_mpi_pack($modulus);
357 # pull an OpenPGP-specified MPI off of a given stream, returning it as
358 # a Crypt::OpenSSL::Bignum.
361 my $readtally = shift;
364 read($instr, $bitlen, 2) or die "could not read MPI length.\n";
365 $bitlen = unpack('n', $bitlen);
368 my $bytestoread = POSIX::floor(($bitlen + 7)/8);
370 read($instr, $ret, $bytestoread) or die "could not read MPI body.\n";
371 $$readtally += $bytestoread;
372 return Crypt::OpenSSL::Bignum->new_from_bin($ret);
376 # FIXME: genericize these to accept either RSA or DSA keys:
377 sub make_rsa_pub_key_body {
379 my $key_timestamp = shift;
381 my ($n, $e) = $key->get_key_parameters();
384 pack('CN', 4, $key_timestamp).
385 pack('C', $asym_algos->{rsa}).
390 sub make_rsa_sec_key_body {
392 my $key_timestamp = shift;
394 # we're not using $a and $b, but we need them to get to $c.
395 my ($n, $e, $d, $p, $q) = $key->get_key_parameters();
397 my $c3 = modular_multi_inverse($p, $q);
399 my $secret_material = mpi_pack($d).
404 # according to Crypt::OpenSSL::RSA, the closest value we can get out
405 # of get_key_parameters is 1/q mod p; but according to sec 5.5.3 of
406 # RFC 4880, we're actually looking for u, the multiplicative inverse
407 # of p, mod q. This is why we're calculating the value directly
408 # with modular_multi_inverse.
411 pack('CN', 4, $key_timestamp).
412 pack('C', $asym_algos->{rsa}).
415 pack('C', 0). # seckey material is not encrypted -- see RFC 4880 sec 5.5.3
417 pack('n', simple_checksum($secret_material));
420 # expects an RSA key (public or private) and a timestamp
423 my $key_timestamp = shift;
425 my $rsabody = make_rsa_pub_key_body($key, $key_timestamp);
427 return Digest::SHA::sha1(pack('Cn', 0x99, length($rsabody)).$rsabody);
431 # FIXME: handle DSA keys as well!
437 # strong assertion of identity is the default (for a self-sig):
438 if (! defined $args->{certification_type}) {
439 $args->{certification_type} = $sig_types->{positive_certification};
442 if (! defined $args->{sig_timestamp}) {
443 $args->{sig_timestamp} = time();
445 my $key_timestamp = $args->{key_timestamp} + 0;
447 # generate and aggregate subpackets:
451 if (! defined $args->{usage_flags}) {
452 $flags = $usage_flags->{certify};
454 my @ff = split(",", $args->{usage_flags});
455 foreach my $f (@ff) {
456 if (! defined $usage_flags->{$f}) {
457 die "No such flag $f";
459 $flags |= $usage_flags->{$f};
462 my $usage_subpacket = pack('CCC', 2, $subpacket_types->{usage_flags}, $flags);
464 # how should we determine how far off to set the expiration date?
465 # default is no expiration. Specify the timestamp in seconds from the
467 my $expiration_subpacket = '';
468 if (defined $args->{expiration}) {
469 my $expires_in = $args->{expiration} + 0;
470 $expiration_subpacket = pack('CCN', 5, $subpacket_types->{key_expiration_time}, $expires_in);
474 # prefer AES-256, AES-192, AES-128, CAST5, 3DES:
475 my $pref_sym_algos = pack('CCCCCCC', 6, $subpacket_types->{preferred_cipher},
480 $ciphers->{tripledes}
483 # prefer SHA-512, SHA-384, SHA-256, SHA-224, RIPE-MD/160, SHA-1
484 my $pref_hash_algos = pack('CCCCCCCC', 7, $subpacket_types->{preferred_digest},
489 $digests->{ripemd160},
493 # prefer ZLIB, BZip2, ZIP
494 my $pref_zip_algos = pack('CCCCC', 4, $subpacket_types->{preferred_compression},
500 # we support the MDC feature:
501 my $feature_subpacket = pack('CCC', 2, $subpacket_types->{features},
504 # keyserver preference: only owner modify (???):
505 my $keyserver_pref = pack('CCC', 2, $subpacket_types->{keyserver_prefs},
506 $keyserver_prefs->{nomodify});
509 $args->{hashed_subpackets} =
511 $expiration_subpacket.
518 return gensig($rsa, $uid, $args);
521 # FIXME: handle non-RSA keys
523 # FIXME: this currently only makes self-sigs -- we should parameterize
524 # it to make certifications over keys other than the issuer.
530 # FIXME: allow signature creation using digests other than SHA256
531 $rsa->use_sha256_hash();
533 # see page 22 of RFC 4880 for why i think this is the right padding
535 $rsa->use_pkcs1_padding();
537 if (! $rsa->check_key()) {
538 die "key does not check\n";
541 my $certtype = $args->{certification_type} + 0;
543 my $version = pack('C', 4);
544 my $sigtype = pack('C', $certtype);
546 my $pubkey_algo = pack('C', $asym_algos->{rsa});
547 # SHA256 FIXME: allow signature creation using digests other than SHA256
548 my $hash_algo = pack('C', $digests->{sha256});
550 # FIXME: i'm worried about generating a bazillion new OpenPGP
551 # certificates from the same key, which could easily happen if you run
552 # this script more than once against the same key (because the
553 # timestamps will differ). How can we prevent this?
555 # this argument (if set) overrides the current time, to
556 # be able to create a standard key. If we read the key from a file
557 # instead of stdin, should we use the creation time on the file?
558 my $sig_timestamp = ($args->{sig_timestamp} + 0);
559 my $key_timestamp = ($args->{key_timestamp} + 0);
561 if ($key_timestamp > $sig_timestamp) {
562 die "key timestamp must not be later than signature timestamp\n";
565 my $creation_time_packet = pack('CCN', 5, $subpacket_types->{sig_creation_time}, $sig_timestamp);
567 my $hashed_subs = $creation_time_packet.$args->{hashed_subpackets};
569 my $subpacket_octets = pack('n', length($hashed_subs));
571 my $sig_data_to_be_hashed =
579 my $pubkey = make_rsa_pub_key_body($rsa, $key_timestamp);
581 # this is for signing. it needs to be an old-style header with a
582 # 2-packet octet count.
584 my $key_data = make_packet($packet_types->{pubkey}, $pubkey, {'packet_length'=>2});
586 # take the last 8 bytes of the fingerprint as the keyid:
587 my $keyid = substr(fingerprint($rsa, $key_timestamp), 20 - 8, 8);
589 # the v4 signature trailer is:
591 # version number, literal 0xff, and then a 4-byte count of the
592 # signature data itself.
593 my $trailer = pack('CCN', 4, 0xff, length($sig_data_to_be_hashed));
596 pack('CN', 0xb4, length($uid)).
602 $sig_data_to_be_hashed.
605 # FIXME: handle signatures over digests other than SHA256:
606 my $data_hash = Digest::SHA::sha256_hex($datatosign);
608 my $issuer_packet = pack('CCa8', 9, $subpacket_types->{issuer}, $keyid);
610 my $sig = Crypt::OpenSSL::Bignum->new_from_bin($rsa->sign($datatosign));
613 $sig_data_to_be_hashed.
614 pack('n', length($issuer_packet)).
616 pack('n', hex(substr($data_hash, 0, 4))).
619 return make_packet($packet_types->{sig}, $sig_body);
622 # FIXME: switch to passing the whole packet as the arg, instead of the
625 # FIXME: think about native perl representation of the packets instead.
627 # Put a user ID into the $data
632 my $packetlen = shift;
635 ($tag == $packet_types->{uid}) or die "This should not be called on anything but a User ID packet\n";
637 read($instr, $dummy, $packetlen);
638 $data->{uid}->{$dummy} = {};
639 $data->{current}->{uid} = $dummy;
643 # find signatures associated with the given fingerprint and user ID.
648 my $packetlen = shift;
650 ($tag == $packet_types->{sig}) or die "No calling findsig on anything other than a signature packet.\n";
655 read($instr, $dummy, $packetlen - $readbytes) or die "Could not read in this packet.\n";
657 if ((! defined $data->{key}) ||
658 (! defined $data->{uid}) ||
659 (! defined $data->{uid}->{$data->{target}->{uid}})) {
660 # the user ID we are looking for has not been found yet.
664 # FIXME: if we get two primary keys on stdin, both with the same
665 # targetd user ID, we'll store signatures from both keys, which is
668 # the current ID is not what we're looking for:
669 return if ($data->{current}->{uid} ne $data->{target}->{uid});
671 # just storing the raw signatures for the moment:
672 push @{$data->{sigs}}, make_packet($packet_types->{sig}, $dummy);
677 # given an input stream and data, store the found key in data and
678 # consume the rest of the stream corresponding to the packet.
679 # data contains: (fpr: fingerprint to find, key: current best guess at key)
684 my $packetlen = shift;
690 read($instr, $ver, 1) or die "could not read key version\n";
695 printf(STDERR "We only work with version 4 keys. This key appears to be version %s.\n", $ver);
696 read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
701 read($instr, $key_timestamp, 4) or die "could not read key timestamp.\n";
703 $key_timestamp = unpack('N', $key_timestamp);
706 read($instr, $algo, 1) or die "could not read key algorithm.\n";
709 if ($algo != $asym_algos->{rsa}) {
710 printf(STDERR "We only support RSA keys (this key used algorithm %d).\n", $algo);
711 read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
715 ## we have an RSA key.
716 my $modulus = read_mpi($instr, \$readbytes);
717 my $exponent = read_mpi($instr, \$readbytes);
719 my $pubkey = Crypt::OpenSSL::RSA->new_key_from_parameters($modulus, $exponent);
720 my $foundfpr = fingerprint($pubkey, $key_timestamp);
722 my $foundfprstr = Crypt::OpenSSL::Bignum->new_from_bin($foundfpr)->to_hex();
723 # left-pad with 0's to bring up to full 40-char (160-bit) fingerprint:
724 $foundfprstr = sprintf("%040s", $foundfprstr);
728 if ((!defined($data->{target}->{fpr})) ||
729 (substr($foundfprstr, -1 * length($data->{target}->{fpr})) eq $data->{target}->{fpr})) {
730 if (defined($data->{key})) {
731 die "Found two matching keys.\n";
733 $data->{key} = { 'rsa' => $pubkey,
734 'timestamp' => $key_timestamp };
738 if ($tag != $packet_types->{seckey} &&
739 $tag != $packet_types->{sec_subkey}) {
740 if ($readbytes < $packetlen) {
741 read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
746 # we don't think the public part of this key matches
747 if ($readbytes < $packetlen) {
748 read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
754 read($instr, $s2k, 1) or die "Could not read S2K octet.\n";
758 printf(STDERR "We cannot handle encrypted secret keys. Skipping!\n") ;
759 read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
763 # secret material is unencrypted
764 # see http://tools.ietf.org/html/rfc4880#section-5.5.3
765 my $d = read_mpi($instr, \$readbytes);
766 my $p = read_mpi($instr, \$readbytes);
767 my $q = read_mpi($instr, \$readbytes);
768 my $u = read_mpi($instr, \$readbytes);
771 read($instr, $checksum, 2) or die "Could not read checksum of secret key material.\n";
773 $checksum = unpack('n', $checksum);
775 # FIXME: compare with the checksum! how? the data is
776 # gone into the Crypt::OpenSSL::Bignum
778 $data->{key}->{rsa} = Crypt::OpenSSL::RSA->new_key_from_parameters($modulus,
784 $data->{key}->{rsa}->check_key() or die "Secret key is not a valid RSA key.\n";
786 if ($readbytes < $packetlen) {
787 read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
796 if (length($fpr) < 8) {
797 die "We need at least 8 hex digits of fingerprint.\n";
802 my $data = { target => { fpr => $fpr,
805 my $subs = { $packet_types->{pubkey} => \&findkey,
806 $packet_types->{pub_subkey} => \&findkey,
807 $packet_types->{seckey} => \&findkey,
808 $packet_types->{sec_subkey} => \&findkey };
810 packetwalk($instr, $subs, $data);
812 return $data->{key}->{rsa};
819 my $packetlen = shift;
821 findkey($data, $instr, $tag, $packetlen);
822 if (defined($data->{key})) {
823 if (defined($data->{key}->{rsa}) && defined($data->{key}->{timestamp})) {
824 $data->{keys}->{fingerprint($data->{key}->{rsa}, $data->{key}->{timestamp})} = $data->{key};
826 die "should have found some key here";
832 sub getallprimarykeys {
835 my $subs = { $packet_types->{pubkey} => \&findkeyfprs,
836 $packet_types->{seckey} => \&findkeyfprs,
838 my $data = {target => { } };
840 packetwalk($instr, $subs, $data);
842 if (defined $data->{keys}) {
843 return $data->{keys};
855 if ((! defined $fpr) ||
856 (length($fpr) < 8)) {
857 die "We need at least 8 hex digits of fingerprint.\n";
862 if (! defined $uid) {
863 die "No User ID defined.\n";
866 my $data = { target => { fpr => $fpr,
870 my $subs = { $packet_types->{seckey} => \&findkey,
871 $packet_types->{uid} => \&finduid,
872 $packet_types->{sig} => \&findsig,
875 packetwalk($instr, $subs, $data);
877 if ((! defined $data->{key}) ||
878 (! defined $data->{key}->{rsa}) ||
879 (! defined $data->{key}->{timestamp})) {
880 die "The key requested was not found.\n"
883 if (defined $data->{uid}->{$uid}) {
884 die "The requested User ID '$uid' is already associated with this key.\n";
886 $args->{key_timestamp} = $data->{key}->{timestamp};
889 make_packet($packet_types->{pubkey}, make_rsa_pub_key_body($data->{key}->{rsa}, $data->{key}->{timestamp})).
890 make_packet($packet_types->{uid}, $uid).
891 makeselfsig($data->{key}->{rsa},
904 if ((! defined $fpr) ||
905 (length($fpr) < 8)) {
906 die "We need at least 8 hex digits of fingerprint.\n";
911 if (! defined $uid) {
912 die "No User ID defined.\n";
915 my $data = { target => { fpr => $fpr,
919 my $subs = { $packet_types->{seckey} => \&findkey,
920 $packet_types->{uid} => \&finduid,
921 $packet_types->{sig} => \&findsig,
924 packetwalk($instr, $subs, $data);
926 if ((! defined $data->{uid}) ||
927 (! defined $data->{uid}->{$uid})) {
928 die "The User ID \"$uid\" is not associated with this key";
931 if ((! defined $data->{key}) ||
932 (! defined $data->{key}->{rsa}) ||
933 (! defined $data->{key}->{timestamp})) {
934 die "The key requested was not found."
937 my $revocation_reason = 'No longer using this hostname';
938 if (defined $data->{revocation_reason}) {
939 $revocation_reason = $data->{revocation_reason};
942 my $rev_reason_subpkt = prefixsubpacket(pack('CC',
943 $subpacket_types->{revocation_reason},
944 $revocation_reasons->{user_id_no_longer_valid}).
947 if (! defined $sigtime) {
950 # what does a signature like this look like?
951 my $args = { key_timestamp => $data->{key}->{timestamp},
952 sig_timestamp => $sigtime,
953 certification_type => $sig_types->{certification_revocation},
954 hashed_subpackets => $rev_reason_subpkt,
958 make_packet($packet_types->{pubkey}, make_rsa_pub_key_body($data->{key}->{rsa}, $data->{key}->{timestamp})).
959 make_packet($packet_types->{uid}, $uid).
960 join('', @{$data->{sigs}}).
961 gensig($data->{key}->{rsa}, $uid, $args);
965 # see 5.2.3.1 for tips on how to calculate the length of a subpacket:
966 sub prefixsubpacket {
967 my $subpacket = shift;
969 my $len = length($subpacket);
974 $prefix = pack('C', $len);
975 } elsif ($len < 16576) {
977 my $second = $in%256;
978 my $first = ($in - $second)>>8;
979 $prefix = pack('CC', $first + 192, $second)
981 $prefix = pack('CN', 255, $len);
983 return $prefix.$subpacket;
997 while (! eof($instr)) {
998 read($instr, $packettag, 1);
999 $packettag = ord($packettag);
1002 if ( ! (0x80 & $packettag)) {
1003 die "This is not an OpenPGP packet\n";
1005 if (0x40 & $packettag) {
1006 # this is a new-format packet.
1007 $tag = (0x3f & $packettag);
1009 read($instr, $nextlen, 1);
1010 $nextlen = ord($nextlen);
1011 if ($nextlen < 192) {
1012 $packetlen = $nextlen;
1013 } elsif ($nextlen < 224) {
1015 read($instr, $newoct, 1);
1016 $newoct = ord($newoct);
1017 $packetlen = (($nextlen - 192) << 8) + ($newoct) + 192;
1018 } elsif ($nextlen == 255) {
1019 read($instr, $nextlen, 4);
1020 $packetlen = unpack('N', $nextlen);
1022 # packet length is undefined.
1025 # this is an old-format packet.
1027 $lentype = 0x03 & $packettag;
1028 $tag = ( 0x3c & $packettag ) >> 2;
1029 if ($lentype == 0) {
1030 read($instr, $packetlen, 1) or die "could not read packet length\n";
1031 $packetlen = unpack('C', $packetlen);
1032 } elsif ($lentype == 1) {
1033 read($instr, $packetlen, 2) or die "could not read packet length\n";
1034 $packetlen = unpack('n', $packetlen);
1035 } elsif ($lentype == 2) {
1036 read($instr, $packetlen, 4) or die "could not read packet length\n";
1037 $packetlen = unpack('N', $packetlen);
1039 # packet length is undefined.
1043 if (! defined($packetlen)) {
1044 die "Undefined packet lengths are not supported.\n";
1047 if (defined $subs->{$tag}) {
1048 $subs->{$tag}($data, $instr, $tag, $packetlen);
1050 read($instr, $dummy, $packetlen) or die "Could not skip past this packet!\n";
1054 return $data->{key};
1058 for (basename($0)) {
1059 if (/^pem2openpgp$/) {
1064 defined($uid) or die "You must specify a user ID string.\n";
1066 # FIXME: fail if there is no given user ID; or should we default to
1067 # hostname_long() from Sys::Hostname::Long ?
1069 if (defined $ENV{PEM2OPENPGP_NEWKEY}) {
1070 $rsa = Crypt::OpenSSL::RSA->generate_key($ENV{PEM2OPENPGP_NEWKEY});
1077 $rsa = Crypt::OpenSSL::RSA->new_private_key($stdin);
1080 my $key_timestamp = $ENV{PEM2OPENPGP_KEY_TIMESTAMP};
1081 my $sig_timestamp = $ENV{PEM2OPENPGP_TIMESTAMP};
1082 $sig_timestamp = time() if (!defined $sig_timestamp);
1083 $key_timestamp = $sig_timestamp if (!defined $key_timestamp);
1086 make_packet($packet_types->{seckey}, make_rsa_sec_key_body($rsa, $key_timestamp)).
1087 make_packet($packet_types->{uid}, $uid).
1090 { sig_timestamp => $sig_timestamp,
1091 key_timestamp => $key_timestamp,
1092 expiration => $ENV{PEM2OPENPGP_EXPIRATION},
1093 usage_flags => $ENV{PEM2OPENPGP_USAGE_FLAGS},
1097 elsif (/^openpgp2ssh$/) {
1100 open($instream,'-');
1101 binmode($instream, ":bytes");
1102 my $key = openpgp2rsa($instream, $fpr);
1103 if (defined($key)) {
1104 if ($key->is_private()) {
1105 print $key->get_private_key_string();
1107 print "ssh-rsa ".encode_base64(openssh_pubkey_pack($key), '')."\n";
1110 die "No matching key found.\n";
1113 elsif (/^keytrans$/) {
1114 # subcommands when keytrans is invoked directly are UNSUPPORTED,
1115 # UNDOCUMENTED, and WILL NOT BE MAINTAINED.
1116 my $subcommand = shift;
1118 if (/^revokeuserid$/) {
1122 open($instream,'-');
1123 binmode($instream, ":bytes");
1125 my $revcert = revokeuserid($instream, $fpr, $uid, $ENV{PEM2OPENPGP_TIMESTAMP});
1128 } elsif (/^adduserid$/) {
1132 open($instream,'-');
1133 binmode($instream, ":bytes");
1134 my $newuid = adduserid($instream, $fpr, $uid,
1135 { sig_timestamp => $ENV{PEM2OPENPGP_TIMESTAMP},
1136 expiration => $ENV{PEM2OPENPGP_EXPIRATION},
1137 usage_flags => $ENV{PEM2OPENPGP_USAGE_FLAGS},
1141 } elsif (/^listfprs$/) {
1143 open($instream,'-');
1144 binmode($instream, ":bytes");
1145 my $keys = getallprimarykeys($instream);
1146 printf("%s\n", join("\n", map { uc(unpack('H*', $_)) } keys(%{$keys})));
1148 die "Unrecognized subcommand. keytrans subcommands are not a stable interface!\n";
1153 die "Unrecognized keytrans call.\n";