shamir.1: Add manpage.

[distorted-keys] / shamir.in

diff --git a/shamir.in b/shamir.in
index 116c7125f1e6569e245e69277877724a647c2f16..15665ea20d9571142850bf5fe82c68cea5dba93a 100755 (executable)
--- a/shamir.in
+++ b/shamir.in
@@ -7,18 +7,20 @@
 
 ###----- Licensing notice ---------------------------------------------------
 ###
-### This program is free software; you can redistribute it and/or modify
+### This file is part of the distorted.org.uk key management suite.
+###
+### distorted-keys 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 2 of the License, or
 ### (at your option) any later version.
 ###
-### This program is distributed in the hope that it will be useful,
+### distorted-keys 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 this program; if not, write to the Free Software Foundation,
+### along with distorted-keys; if not, write to the Free Software Foundation,
 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
 from __future__ import with_statement
@@ -30,6 +32,9 @@ import base64 as B
 from cStringIO import StringIO
 import optparse as OPT
 
+PACKAGE = '@PACKAGE@'
+VERSION = '@VERSION@'
+
 ###--------------------------------------------------------------------------
 ### Arithmetic in GF(2^8).
 ###
@@ -541,7 +546,16 @@ class SubcommandOptionParser (OPT.OptionParser, object):
     opts, args = op.parse_args(args[1:])
     sub.func(gopts, opts, args)
 
-OPTPARSE = SubcommandOptionParser(description = """\
+def subcommand(name, usage, desc, opts = []):
+  def _(func):
+    OPTPARSE.add_subcommand(name, func, usage, desc, opts)
+    return func
+  return _
+
+OPTPARSE = SubcommandOptionParser(
+  usage = '%prog SUBCOMMAND [ARGS ...]',
+  version = '%%prog, %s version %s' % (PACKAGE, VERSION),
+  description = """\
 Split and recombine secrets using Shamir's secret sharing system.
 """)
 
@@ -554,6 +568,18 @@ def parse_sharing(string):
     raise ValueError, "no `/'"
   return int(string[slash + 1:]), int(string[:slash])
 
+@subcommand('issue', '[-H HASHFN] THRESH/COUNT [SECRET-FILE]',
+  """\
+Issue shares of a secret.  The secret (as a binary lump) is read from
+SECRET-FILE, or standard input if SECRET-FILE is omitted.  COUNT + 1 lines
+are written to standard output: the first line contains the sharing
+parameters, and does not need to be kept especially secret (though it
+contains a hash of the secret, so it compromises the unconditional security
+of the secret sharing scheme); the remaining lines are the shares, one per
+line.  All of the lines are plain text.""",
+  [OPT.make_option('-H', '--hash-function', type = 'string',
+                   action = 'store', dest = 'hashfn', default = 'sha256',
+                   help = 'Hash function for verifying the share.')])
 def cmd_issue(gopts, opts, args):
 
   if len(args) < 1 or len(args) > 2:
@@ -581,24 +607,18 @@ def cmd_issue(gopts, opts, args):
     share = Share(i, ss.issue(i + 1))
     print share.encode()
 
-OPTPARSE.add_subcommand(
-  'issue', cmd_issue,
-  '[-H HASHFN] THRESH/COUNT [SECRET-FILE]',
-  """\
-Issue shares of a secret.  The secret (as a binary lump) is read from
-SECRET-FILE, or standard input if SECRET-FILE is omitted.  COUNT + 1 lines
-are written to standard output: the first line contains the sharing
-parameters, and does not need to be kept especially secret (though it
-contains a hash of the secret, so it compromises the unconditional security
-of the secret sharing scheme); the remaining lines are the shares, one per
-line.  All of the lines are plain text.""",
-  [OPT.make_option('-H', '--hash-function', type = 'string',
-                   action = 'store', dest = 'hashfn', default = 'sha256',
-                   help = 'Hash function for verifying the share.')])
-
 ###--------------------------------------------------------------------------
 ### Recover a secret from shares.
 
+@subcommand('recover', '',
+  """\
+Standard input should contain a number of lines.  The first line should
+contain the secret sharing parameters (the first line output by `issue');
+the remaining lines should contain shares.  The shares may be supplied in
+any order.  The secret is written to the OUTPUT file, or standard output.""",
+  [OPT.make_option('-o', '--output', action = 'store', type = 'string',
+                  dest = 'file', default = '-',
+                  help = 'Write the secret to FILE.')])
 def cmd_recover(gopts, opts, args):
 
   ## Keep track of how well we've done so far.  Report all of the things
@@ -665,18 +685,6 @@ def cmd_recover(gopts, opts, args):
     with open(opts.file, 'wb') as f:
       f.write(secret.secret)
 
-OPTPARSE.add_subcommand(
-  'recover', cmd_recover,
-  '',
-  """\
-Standard input should contain a number of lines.  The first line should
-contain the secret sharing parameters (the first line output by `issue');
-the remaining lines should contain shares.  The shares may be supplied in
-any order.  The secret is written to the OUTPUT file, or standard output.""",
-  [OPT.make_option('-o', '--output', action = 'store', type = 'string',
-                  dest = 'file', default = '-',
-                  help = 'Write the secret to FILE.')])
-
 ###----- That's all, folks --------------------------------------------------
 
 if __name__ == '__main__':