X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=src%2Fshare%2Fkeytrans;h=591cb9d580454cd26e512029713f1111b4d889e5;hb=a6a217b5475f3e4e91706f57c26fc36497b545e1;hp=e6777ffd4a35805d96cbd55ead27042cdbecd1f4;hpb=5df09d935f33477cdd9763c0e9c1ba7c8073aea0;p=monkeysphere.git

diff --git a/src/share/keytrans b/src/share/keytrans
index e6777ff..591cb9d 100755
--- a/src/share/keytrans
+++ b/src/share/keytrans
@@ -1,4 +1,4 @@
-#!/usr/bin/perl -w -T
+#!/usr/bin/perl -T
 
 # keytrans: this is an RSA key translation utility; it is capable of
 # transforming RSA keys (both public keys and secret keys) between
@@ -54,7 +54,7 @@ use File::Basename;
 use Crypt::OpenSSL::RSA;
 use Crypt::OpenSSL::Bignum;
 use Crypt::OpenSSL::Bignum::CTX;
-use Digest::SHA1;
+use Digest::SHA;
 use MIME::Base64;
 use POSIX;
 
@@ -368,12 +368,12 @@ sub read_mpi {
 # FIXME: genericize these to accept either RSA or DSA keys:
 sub make_rsa_pub_key_body {
   my $key = shift;
-  my $timestamp = shift;
+  my $key_timestamp = shift;
 
   my ($n, $e) = $key->get_key_parameters();
 
   return
-    pack('CN', 4, $timestamp).
+    pack('CN', 4, $key_timestamp).
       pack('C', $asym_algos->{rsa}).
 	mpi_pack($n).
 	  mpi_pack($e);
@@ -381,7 +381,7 @@ sub make_rsa_pub_key_body {
 
 sub make_rsa_sec_key_body {
   my $key = shift;
-  my $timestamp = shift;
+  my $key_timestamp = shift;
 
   # we're not using $a and $b, but we need them to get to $c.
   my ($n, $e, $d, $p, $q) = $key->get_key_parameters();
@@ -400,7 +400,7 @@ sub make_rsa_sec_key_body {
   # with modular_multi_inverse.
 
   return
-    pack('CN', 4, $timestamp).
+    pack('CN', 4, $key_timestamp).
       pack('C', $asym_algos->{rsa}).
 	mpi_pack($n).
 	  mpi_pack($e).
@@ -412,11 +412,11 @@ sub make_rsa_sec_key_body {
 # expects an RSA key (public or private) and a timestamp
 sub fingerprint {
   my $key = shift;
-  my $timestamp = shift;
+  my $key_timestamp = shift;
 
-  my $rsabody = make_rsa_pub_key_body($key, $timestamp);
+  my $rsabody = make_rsa_pub_key_body($key, $key_timestamp);
 
-  return Digest::SHA1::sha1(pack('Cn', 0x99, length($rsabody)).$rsabody);
+  return Digest::SHA::sha1(pack('Cn', 0x99, length($rsabody)).$rsabody);
 }
 
 
@@ -426,7 +426,7 @@ sub pem2openpgp {
   my $uid = shift;
   my $args = shift;
 
-  $rsa->use_sha1_hash();
+  $rsa->use_sha256_hash();
 
   # see page 22 of RFC 4880 for why i think this is the right padding
   # choice to use:
@@ -436,30 +436,42 @@ sub pem2openpgp {
     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;
+  }
+
   my $version = pack('C', 4);
-  # strong assertion of identity:
-  my $sigtype = pack('C', $sig_types->{positive_certification});
+  my $sigtype = pack('C', $certtype);
   # RSA
   my $pubkey_algo = pack('C', $asym_algos->{rsa});
-  # SHA1
-  my $hash_algo = pack('C', $digests->{sha1});
+  # 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 environment variable (if set) overrides the current time, to
-  # be able to create a standard key?  If we read the key from a file
+  # 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 $timestamp = 0;
-  if (defined $args->{timestamp}) {
-    $timestamp = ($args->{timestamp} + 0);
+  my $sig_timestamp = 0;
+  if (defined $args->{sig_timestamp}) {
+    $sig_timestamp = ($args->{sig_timestamp} + 0);
   } else {
-    $timestamp = time();
+    $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";
   }
 
-  my $creation_time_packet = pack('CCN', 5, $subpacket_types->{sig_creation_time}, $timestamp);
+  my $creation_time_packet = pack('CCN', 5, $subpacket_types->{sig_creation_time}, $sig_timestamp);
 
 
   my $flags = 0;
@@ -497,11 +509,14 @@ sub pem2openpgp {
 			    $ciphers->{tripledes}
 			   );
 
-  # prefer SHA-1, SHA-256, RIPE-MD/160
-  my $pref_hash_algos = pack('CCCCC', 4, $subpacket_types->{preferred_digest},
-			     $digests->{sha1},
+  # prefer SHA-512, SHA-384, SHA-256, SHA-224, RIPE-MD/160, SHA-1
+  my $pref_hash_algos = pack('CCCCCCCC', 7, $subpacket_types->{preferred_digest},
+			     $digests->{sha512},
+			     $digests->{sha384},
 			     $digests->{sha256},
-			     $digests->{ripemd160}
+			     $digests->{sha224},
+			     $digests->{ripemd160},
+			     $digests->{sha1}
 			    );
 
   # prefer ZLIB, BZip2, ZIP
@@ -539,8 +554,8 @@ sub pem2openpgp {
 	    $subpacket_octets.
 	      $subpackets_to_be_hashed;
 
-  my $pubkey = make_rsa_pub_key_body($rsa, $timestamp);
-  my $seckey = make_rsa_sec_key_body($rsa, $timestamp);
+  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.
@@ -548,7 +563,7 @@ sub pem2openpgp {
   my $key_data = make_packet($packet_types->{pubkey}, $pubkey, {'packet_length'=>2});
 
   # take the last 8 bytes of the fingerprint as the keyid:
-  my $keyid = substr(fingerprint($rsa, $timestamp), 20 - 8, 8);
+  my $keyid = substr(fingerprint($rsa, $key_timestamp), 20 - 8, 8);
 
   # the v4 signature trailer is:
 
@@ -566,7 +581,7 @@ sub pem2openpgp {
 	$sig_data_to_be_hashed.
 	  $trailer;
 
-  my $data_hash = Digest::SHA1::sha1_hex($datatosign);
+  my $data_hash = Digest::SHA::sha256_hex($datatosign);
 
   my $issuer_packet = pack('CCa8', 9, $subpacket_types->{issuer}, $keyid);
 
@@ -585,6 +600,119 @@ sub pem2openpgp {
 	make_packet($packet_types->{sig}, $sig_body);
 }
 
+# FIXME: switch to passing the whole packet as the arg, instead of the
+# input stream.
+
+# 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)
+sub findkey {
+  my $data = shift;
+  my $instr = shift;
+  my $tag = shift;
+  my $packetlen = shift;
+
+  my $dummy;
+  my $ver;
+  my $readbytes = 0;
+
+  read($instr, $ver, 1) or die "could not read key version\n";
+  $readbytes += 1;
+  $ver = ord($ver);
+
+  if ($ver != 4) {
+    printf(STDERR "We only work with version 4 keys.  This key appears to be version %s.\n", $ver);
+    read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
+    return;
+  }
+
+  my $key_timestamp;
+  read($instr, $key_timestamp, 4) or die "could not read key timestamp.\n";
+  $readbytes += 4;
+  $key_timestamp = unpack('N', $key_timestamp);
+
+  my $algo;
+  read($instr, $algo, 1) or die "could not read key algorithm.\n";
+  $readbytes += 1;
+  $algo = ord($algo);
+  if ($algo != $asym_algos->{rsa}) {
+    printf(STDERR "We only support RSA keys (this key used algorithm %d).\n", $algo);
+    read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
+    return;
+  }
+
+  ## we have an RSA key.
+  my $modulus = read_mpi($instr, \$readbytes);
+  my $exponent = read_mpi($instr, \$readbytes);
+
+  my $pubkey = Crypt::OpenSSL::RSA->new_key_from_parameters($modulus, $exponent);
+  my $foundfpr = fingerprint($pubkey, $key_timestamp);
+
+  my $foundfprstr = Crypt::OpenSSL::Bignum->new_from_bin($foundfpr)->to_hex();
+  # left-pad with 0's to bring up to full 40-char (160-bit) fingerprint:
+  $foundfprstr = sprintf("%040s", $foundfprstr);
+
+  # is this a match?
+  if ((!defined($data->{fpr})) ||
+      (substr($foundfprstr, -1 * length($data->{fpr})) eq $data->{fpr})) {
+    if (defined($data->{key})) {
+      die "Found two matching keys.\n";
+    }
+    $data->{key} = $pubkey;
+  }
+
+  if ($tag != $packet_types->{seckey} &&
+      $tag != $packet_types->{sec_subkey}) {
+    if ($readbytes < $packetlen) {
+      read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
+    }
+    return;
+  }
+  if (!defined($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";
+    }
+    return;
+  }
+
+  my $s2k;
+  read($instr, $s2k, 1) or die "Could not read S2K octet.\n";
+  $readbytes += 1;
+  $s2k = ord($s2k);
+  if ($s2k != 0) {
+    printf(STDERR "We cannot handle encrypted secret keys.  Skipping!\n") ;
+    read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
+    return;
+  }
+
+  # secret material is unencrypted
+  # see http://tools.ietf.org/html/rfc4880#section-5.5.3
+  my $d = read_mpi($instr, \$readbytes);
+  my $p = read_mpi($instr, \$readbytes);
+  my $q = read_mpi($instr, \$readbytes);
+  my $u = read_mpi($instr, \$readbytes);
+
+  my $checksum;
+  read($instr, $checksum, 2) or die "Could not read checksum of secret key material.\n";
+  $readbytes += 2;
+  $checksum = unpack('n', $checksum);
+
+  # 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);
+
+  $data->{key}->check_key() or die "Secret key is not a valid RSA key.\n";
+
+  if ($readbytes < $packetlen) {
+    read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
+  }
+}
 
 sub openpgp2ssh {
   my $instr = shift;
@@ -597,12 +725,26 @@ sub openpgp2ssh {
     $fpr = uc($fpr);
   }
 
+  my $data = { 'fpr' => $fpr};
+  my $subs = { $packet_types->{pubkey} => \&findkey,
+	       $packet_types->{pub_subkey} => \&findkey,
+	       $packet_types->{seckey} => \&findkey,
+	       $packet_types->{sec_subkey} => \&findkey };
+
+  packetwalk($instr, $subs, $data);
+
+  return $data->{key};
+}
+
+sub packetwalk {
+  my $instr = shift;
+  my $subs = shift;
+  my $data = shift;
+
   my $packettag;
   my $dummy;
   my $tag;
 
-  my $key;
-
   while (! eof($instr)) {
     read($instr, $packettag, 1);
     $packettag = ord($packettag);
@@ -612,6 +754,7 @@ sub openpgp2ssh {
       die "This is not an OpenPGP packet\n";
     }
     if (0x40 & $packettag) {
+      # this is a new-format packet.
       $tag = (0x3f & $packettag);
       my $nextlen = 0;
       read($instr, $nextlen, 1);
@@ -630,6 +773,7 @@ sub openpgp2ssh {
 	# packet length is undefined.
       }
     } else {
+      # this is an old-format packet.
       my $lentype;
       $lentype = 0x03 & $packettag;
       $tag = ( 0x3c & $packettag ) >> 2;
@@ -651,100 +795,14 @@ sub openpgp2ssh {
       die "Undefined packet lengths are not supported.\n";
     }
 
-    if ($tag == $packet_types->{pubkey} ||
-	$tag == $packet_types->{pub_subkey} ||
-	$tag == $packet_types->{seckey} ||
-	$tag == $packet_types->{sec_subkey}) {
-      my $ver;
-      my $readbytes = 0;
-      read($instr, $ver, 1) or die "could not read key version\n";
-      $readbytes += 1;
-      $ver = ord($ver);
-
-      if ($ver != 4) {
-	printf(STDERR "We only work with version 4 keys.  This key appears to be version %s.\n", $ver);
-	read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
-      } else {
-
-	my $timestamp;
-	read($instr, $timestamp, 4) or die "could not read key timestamp.\n";
-	$readbytes += 4;
-	$timestamp = unpack('N', $timestamp);
-
-	my $algo;
-	read($instr, $algo, 1) or die "could not read key algorithm.\n";
-	$readbytes += 1;
-	$algo = ord($algo);
-	if ($algo != $asym_algos->{rsa}) {
-	  printf(STDERR "We only support RSA keys (this key used algorithm %d).\n", $algo);
-	  read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
-	} else {
-	  ## we have an RSA key.
-	  my $modulus = read_mpi($instr, \$readbytes);
-	  my $exponent = read_mpi($instr, \$readbytes);
-
-	  my $pubkey = Crypt::OpenSSL::RSA->new_key_from_parameters($modulus, $exponent);
-	  my $foundfpr = fingerprint($pubkey, $timestamp);
-
-	  my $foundfprstr = Crypt::OpenSSL::Bignum->new_from_bin($foundfpr)->to_hex();
-
-	  # is this a match?
-	  if ((!defined($fpr)) ||
-	      (substr($foundfprstr, -1 * length($fpr)) eq $fpr)) {
-	    if (defined($key)) {
-	      die "Found two matching keys.\n";
-	    }
-	    $key = $pubkey;
-	  }
-
-	  if ($tag == $packet_types->{seckey} ||
-	      $tag == $packet_types->{sec_subkey}) {
-	    if (!defined($key)) { # we don't think the public part of
-                                  # this key matches
-	      read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
-	    } else {
-	      my $s2k;
-	      read($instr, $s2k, 1) or die "Could not read S2K octet.\n";
-	      $readbytes += 1;
-	      $s2k = ord($s2k);
-	      if ($s2k == 0) {
-		# secret material is unencrypted
-		# see http://tools.ietf.org/html/rfc4880#section-5.5.3
-		my $d = read_mpi($instr, \$readbytes);
-		my $p = read_mpi($instr, \$readbytes);
-		my $q = read_mpi($instr, \$readbytes);
-		my $u = read_mpi($instr, \$readbytes);
-
-		my $checksum;
-		read($instr, $checksum, 2) or die "Could not read checksum of secret key material.\n";
-		$readbytes += 2;
-		$checksum = unpack('n', $checksum);
-
-		# FIXME: compare with the checksum!  how?  the data is
-		# gone into the Crypt::OpenSSL::Bignum
-
-		$key = Crypt::OpenSSL::RSA->new_key_from_parameters($modulus,
-								    $exponent,
-								    $d,
-								    $p,
-								    $q);
-
-		$key->check_key() or die "Secret key is not a valid RSA key.\n";
-	      } else {
-		print(STDERR "We cannot handle encrypted secret keys.  Skipping!\n") ;
-		read($instr, $dummy, $packetlen - $readbytes) or die "Could not skip past this packet.\n";
-	      }
-	    }
-	  }
-
-	}
-      }
+    if (defined $subs->{$tag}) {
+      $subs->{$tag}($data, $instr, $tag, $packetlen);
     } else {
       read($instr, $dummy, $packetlen) or die "Could not skip past this packet!\n";
     }
   }
 
-  return $key;
+  return $data->{key};
 }
 
 
@@ -759,7 +817,6 @@ for (basename($0)) {
     # FIXME: fail if there is no given user ID; or should we default to
     # hostname_long() from Sys::Hostname::Long ?
 
-
     if (defined $ENV{PEM2OPENPGP_NEWKEY}) {
       $rsa = Crypt::OpenSSL::RSA->generate_key($ENV{PEM2OPENPGP_NEWKEY});
     } else {
@@ -773,7 +830,8 @@ for (basename($0)) {
 
     print pem2openpgp($rsa,
 		      $uid,
-		      { timestamp => $ENV{PEM2OPENPGP_TIMESTAMP},
+		      { sig_timestamp => $ENV{PEM2OPENPGP_TIMESTAMP},
+			key_timestamp => $ENV{PEM2OPENPGP_KEY_TIMESTAMP},
 			expiration => $ENV{PEM2OPENPGP_EXPIRATION},
 			usage_flags => $ENV{PEM2OPENPGP_USAGE_FLAGS},
 		      }