GnuPG(3pm)						User Contributed Perl Documentation						GnuPG(3pm)

NAME

       GnuPG - Perl module interface to the GNU Privacy Guard (v1.x.x series)

SYNOPSIS

	   use GnuPG qw( :algo );

	   my $gpg = new GnuPG();

	   $gpg->encrypt(  plaintext	=> "file.txt",	  output	=> "file.gpg",
		   armor    => 1,	  sign	  => 1,
		   passphrase  => $secret );

	   $gpg->decrypt( ciphertext	=> "file.gpg",	  output	=> "file.txt" );

	   $gpg->clearsign( plaintext => "file.txt", output => "file.txt.asc",
		    passphrase => $secret,   armor => 1,
		   );

	   $gpg->verify( signature => "file.txt.asc", file => "file.txt" );

	   $gpg->gen_key( name => "Joe Blow",	     comment => "My GnuPG key",
		  passphrase => $secret,
		   );

DESCRIPTION

       GnuPG is a perl interface to the GNU Privacy Guard. It uses the shared memory coprocess interface that gpg provides for its wrappers. It
       tries its best to map the interactive interface of the gpg to a more programmatic model.

API OVERVIEW

       The API is accessed through methods on a GnuPG object which is a wrapper around the gpg program.  All methods takes their argument using
       named parameters, and errors are returned by throwing an exception (using croak).  If you wan't to catch errors you will have to use eval.

       When handed in a file handle for input or output parameters on many of the functions, the API attempts to tie that handle to STDIN and
       STDOUT. In certain persistent environments (particularly a web environment), this will not work. This problem can be avoided by passing in
       file names to all relevant parameters rather than a Perl file handle.

       There is also a tied file handle interface which you may find more convenient for encryption and decryption. See GnuPG::Tie(3) for details.

CONSTRUCTOR

   new ( [params] )
       You create a new GnuPG wrapper object by invoking its new method.  (How original !).  The module will try to finds the gpg program in your
       path and will croak if it can't find it. Here are the parameters that it accepts :

       gnupg_path
	   Path to the gpg program.

       options
	   Path to the options file for gpg. If not specified, it will use the default one (usually ~/.gnupg/options).

       homedir
	   Path to the gpg home directory. This is the directory that contains the default options file, the public and private key rings as well
	   as the trust database.

       trace
	   If this variable is set to true, gpg debugging output will be sent to stderr.

	   Example: my $gpg = new GnuPG();

METHODS

   gen_key( [params] )
       This methods is used to create a new gpg key pair. The methods croaks if there is an error. It is a good idea to press random keys on the
       keyboard while running this methods because it consumes a lot of entropy from the computer. Here are the parameters it accepts :

       algo
	   This is the algorithm use to create the key. Can be DSA_ELGAMAL, DSA, RSA_RSA or RSA.  It defaults to DSA_ELGAMAL. To import those
	   constant in your name space, use the :algo tag.

       size
	   The size of the public key. Defaults to 1024. Cannot be less than 768 bits, and keys longer than 2048 are also discouraged. (You *DO*
	   know that your monitor may be leaking sensitive information ;-).

       valid
	   How long the key is valid. Defaults to 0 or never expire.

       name
	   This is the only mandatory argument. This is the name that will used to construct the user id.

       email
	   Optional email portion of the user id.

       comment
	   Optional comment portion of the user id.

       passphrase
	   The passphrase that will be used to encrypt the private key. Optional but strongly recommended.

	   Example: $gpg->gen_key( algo => DSA_ELGAMAL, size => 1024,
		       name => "My name" );

   import_keys( [params] )
       Import keys into the GnuPG private or public keyring. The method croaks if it encounters an error. It returns the number of keys imported.
       Parameters :

       keys
	   Only parameter and mandatory. It can either be a filename or a reference to an array containing a list of files that will be imported.

	   Example: $gpg->import_keys( keys => [ qw( key.pub key.sec ) ] );

   export_keys( [params] )
       Exports keys from the GnuPG keyrings. The method croaks if it encounters an error. Parameters :

       keys
	   Optional argument that restricts the keys that will be exported.  Can either be a user id or a reference to an array of userid that
	   specifies the keys to be exported. If left unspecified, all keys will be exported.

       secret
	   If this argument is to true, the secret keys rather than the public ones will be exported.

       all If this argument is set to true, all keys (even those that aren't OpenPGP compliant) will be exported.

       output
	   This argument specifies where the keys will be exported. Can be either a file name or a reference to a file handle. If not specified,
	   the keys will be exported to stdout.

       armor
	   Set this parameter to true, if you want the exported keys to be ASCII armored.

	   Example: $gpg->export_keys( armor => 1, output => "keyring.pub" );

   encrypt( [params] )
       This method is used to encrypt a message, either using assymetric or symmetric cryptography. The methods croaks if an error is encountered.
       Parameters:

       plaintext
	   This argument specifies what to encrypt. It can be either a filename or a reference to a file handle. If left unspecified, STDIN will
	   be encrypted.

       output
	   This optional argument specifies where the ciphertext will be output.  It can be either a file name or a reference to a file handle. If
	   left unspecified, the ciphertext will be sent to STDOUT.

       armor
	   If this parameter is set to true, the ciphertext will be ASCII armored.

       symmetric
	   If this parameter is set to true, symmetric cryptography will be used to encrypt the message. You will need to provide a passphrase
	   parameter.

       recipient
	   If not using symmetric cryptography, you will have to provide this parameter. It should contains the userid of the intended recipient
	   of the message. It will be used to look up the key to use to encrypt the message. The parameter can also take an array ref, if you want
	   to encrypt the message for a group of recipients.

       sign
	   If this parameter is set to true, the message will also be signed. You will probably have to use the passphrase parameter to unlock the
	   private key used to sign message. This option is incompatible with the symmetric one.

       local-user
	   This parameter is used to specified the private key that will be used to sign the message. If left unspecified, the default user will
	   be used. This option only makes sense when using the sign option.

       passphrase
	   This parameter contains either the secret passphrase for the symmetric algorithm or the passphrase that should be used to decrypt the
	   private key.

	   Example: $gpg->encrypt( plaintext => file.txt, output => "file.gpg",
		       sign => 1, passphrase => $secret
		       );

   sign( [params] )
       This method is used create a signature for a file or stream of data.  This method croaks on errors. Parameters :

       plaintext
	   This argument specifies what  to sign. It can be either a filename or a reference to a file handle. If left unspecified, the data read
	   on STDIN will be signed.

       output
	   This optional argument specifies where the signature will be output.  It can be either a file name or a reference to a file handle. If
	   left unspecified, the signature will be sent to STDOUT.

       armor
	   If this parameter is set to true, the signature will be ASCII armored.

       passphrase
	   This parameter contains the secret that should be used to decrypt the private key.

       local-user
	   This parameter is used to specified the private key that will be used to make the signature . If left unspecified, the default user
	   will be used.

       detach-sign
	   If set to true, a digest of the data will be signed rather than the whole file.

	   Example: $gpg->sign( plaintext => "file.txt", output => "file.txt.asc",
		    armor => 1,
		    );

   clearsign( [params] )
       This methods clearsign a message. The output will contains the original message with a signature appended. It takes the same parameters as
       the sign method.

   verify( [params] )
       This method verifies a signature against the signed message. The methods croaks if the signature is invalid or an error is encountered. If
       the signature is valid, it returns an hash with the signature parameters. Here are the method's parameters :

       signature
	   If the message and the signature are in the same file (i.e. a clearsigned message), this parameter can be either a file name or a
	   reference to a file handle. If the signature doesn't follows the message, than it must be the name of the file that contains the
	   signature.

       file
	   This is a file name or a reference to an array of file names that contains the signed data.

       When the signature is valid, here are the elements of the hash that is returned by the method :

       sigid
	   The signature id. This can be used to protect against replay attack.

       date
	   The data at which the signature has been made.

       timestamp
	   The epoch timestamp of the signature.

       keyid
	   The key id used to make the signature.

       user
	   The userid of the signer.

       fingerprint
	   The fingerprint of the signature.

       trust
	   The trust value of the public key of the signer. Those are values that can be imported in your namespace with the :trust tag. They are
	   (TRUST_UNDEFINED, TRUST_NEVER, TRUST_MARGINAL, TRUST_FULLY, TRUST_ULTIMATE).

	   Example : my $sig = $gpg->verify( signature => "file.txt.asc",
			     file => "file.txt" );

   decrypt( [params] )
       This method decrypts an encrypted message. It croaks, if there is an error while decrypting the message. If the message was signed, this
       method also verifies the signature. If decryption is sucessful, the method either returns the valid signature parameters if present, or
       true. Method parameters :

       ciphertext
	   This optional parameter contains either the name of the file containing the ciphertext or a reference to a file handle containing the
	   ciphertext. If not present, STDIN will be decrypted.

       output
	   This optional parameter determines where the plaintext will be stored.  It can be either a file name or a reference to a file handle.
	   If left unspecified, the plaintext will be sent to STDOUT.

       symmetric
	   This should be set to true, if the message is encrypted using symmetric cryptography.

       passphrase
	   The passphrase that should be used to decrypt the message (in the case of a message encrypted using a symmetric cipher) or the secret
	   that will unlock the private key that should be used to decrypt the message.

	   Example: $gpg->decrypt( ciphertext => "file.gpg", output => "file.txt"
		       passphrase => $secret );

BUGS AND LIMITATIONS

       This module doesn't work (yet) with the v2 branch of GnuPG.

AUTHOR

       Francis J. Lacoste <francis.lacoste@Contre.COM>

COPYRIGHT

       Copyright (c) 1999,2000 iNsu Innovations. Inc.  Copyright (c) 2001 Francis J. Lacoste

       This program 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.

SEE ALSO

       GnuPG::Tie

       Alternative module: GnuPG::Interface

       gpg(1)

perl v5.14.2							    2012-04-15								GnuPG(3pm)