Split Duo type out into multiple sub-types

The existing functionality is now in the duo-pam object type.  The old
duo type now returns output in a generic config file, and new types for
the Duo auth proxy in LDAP and Radius proxies are added.

Change-Id: I1525d79b44dafcf3ef85368297baefafcb5dc179

5 files changed, 633 insertions, 22 deletions

diff --git a/perl/lib/Wallet/Admin.pm b/perl/lib/Wallet/Admin.pm
index d32a0c2..381ffc9 100644
--- a/perl/lib/Wallet/Admin.pm
+++ b/perl/lib/Wallet/Admin.pm
@@ -126,6 +126,9 @@ sub default_data {
     # types default rows.
     my @record = ([ qw/ty_name ty_class/ ],
                [ 'duo',        'Wallet::Object::Duo' ],
+               [ 'duo-pam',    'Wallet::Object::Duo::PAM' ],
+               [ 'duo-radius', 'Wallet::Object::Duo::RadiusProxy' ],
+               [ 'duo-ldap',   'Wallet::Object::Duo::LDAPProxy' ],
                [ 'file',       'Wallet::Object::File' ],
                [ 'keytab',     'Wallet::Object::Keytab' ],
                [ 'wa-keyring', 'Wallet::Object::WAKeyring' ]);
diff --git a/perl/lib/Wallet/Object/Duo.pm b/perl/lib/Wallet/Object/Duo.pm
index 6edc4fa..168ec8b 100644
--- a/perl/lib/Wallet/Object/Duo.pm
+++ b/perl/lib/Wallet/Object/Duo.pm
@@ -1,4 +1,4 @@
-# Wallet::Object::Duo -- Duo integration object implementation for the wallet.
+# Wallet::Object::Duo -- Base Duo object implementation for the wallet
 #
 # Written by Russ Allbery <eagle@eyrie.org>
 # Copyright 2014
@@ -29,7 +29,7 @@ use Wallet::Object::Base;
 # This version should be increased on any code change to this module.  Always
 # use two digits for the minor version with a leading zero if necessary so
 # that it will sort properly.
-$VERSION = '0.01';
+$VERSION = '0.02';
 
 ##############################################################################
 # Core methods
@@ -84,7 +84,7 @@ sub new {
 # great here since we don't have a way to communicate the error back to the
 # caller.
 sub create {
-    my ($class, $type, $name, $schema, $creator, $host, $time) = @_;
+    my ($class, $type, $name, $schema, $creator, $host, $time, $duo_type) = @_;
 
     # We have to have a Duo integration key file set.
     if (not $Wallet::Config::DUO_KEY_FILE) {
@@ -104,10 +104,11 @@ sub create {
 
     # Create the object in Duo.
     require Net::Duo::Admin::Integration;
+    $duo_type ||= $Wallet::Config::DUO_TYPE;
     my %data = (
-        name  => "$name ($Wallet::Config::DUO_TYPE)",
+        name  => "$name ($duo_type)",
         notes => 'Managed by wallet',
-        type  => $Wallet::Config::DUO_TYPE,
+        type  => $duo_type,
     );
     my $integration = Net::Duo::Admin::Integration->create ($duo, \%data);
 
@@ -194,10 +195,10 @@ sub get {
     my $config = $json->decode (scalar slurp $Wallet::Config::DUO_KEY_FILE);
 
     # Construct the returned file.
-    my $output = "[duo]\n";
-    $output .= "ikey = $key\n";
-    $output .= 'skey = ' . $integration->secret_key . "\n";
-    $output .= "host = $config->{api_hostname}\n";
+    my $output;
+    $output .= "Integration key: $key\n";
+    $output .= 'Secret key:      ' . $integration->secret_key . "\n";
+    $output .= "Host:            $config->{api_hostname}\n";
 
     # Log the action and return.
     $self->log_action ('get', $user, $host, $time);
@@ -234,12 +235,11 @@ create a Duo integration, return a configuration file containing the key
 and API information for that integration, and delete the integration from
 Duo when the wallet object is destroyed.
 
-Currently, only one configured integration type can be managed by the
-wallet, and the integration information is always returned in the
-configuration file format expected by the Duo UNIX integration.  The
-results of retrieving this object will be text, suitable for putting in
-the UNIX integration configuration file, containing the integration key,
-secret key, and admin hostname for that integration.
+Usually you will want to use one of the subclasses of this module, which
+override the output to give you a configuration fragment suited for a
+specific application type.  However, you can always use this module for
+generic integrations where you don't mind massaging the output into the
+configuration for the application using Duo.
 
 This object can be retrieved repeatedly without changing the secret key,
 matching Duo's native behavior with integrations.  To change the keys of
@@ -258,7 +258,7 @@ implementation.
 
 =over 4
 
-=item create(TYPE, NAME, DBH, PRINCIPAL, HOSTNAME [, DATETIME])
+=item create(TYPE, NAME, DBH, PRINCIPAL, HOSTNAME [, DATETIME, INTEGRATION_TYPE])
 
 This is a class method and should be called on the Wallet::Object::Duo
 class.  It creates a new object with the given TYPE and NAME (TYPE is
@@ -272,9 +272,9 @@ time is used.
 When a new Duo integration object is created, a new integration will be
 created in the configured Duo account and the integration key will be
 stored in the wallet object.  If the integration already exists, create()
-will fail.  The new integration's type is controlled by the DUO_TYPE
-configuration variable, which defaults to C<unix>.  See L<Wallet::Config>
-for more information.
+will fail.  If an integration type isn't given, the new integration's type
+is controlled by the DUO_TYPE configuration variable, which defaults to
+C<unix>.  See L<Wallet::Config> for more information.
 
 If create() fails, it throws an exception.
 
@@ -314,9 +314,6 @@ isn't given, the current time is used.
 =head1 LIMITATIONS
 
 Only one Duo account is supported for a given wallet implementation.
-Currently, only one Duo integration type is supported as well.  Further
-development should expand the available integration types, possibly as
-additional wallet object types.
 
 =head1 SEE ALSO
 
diff --git a/perl/lib/Wallet/Object/Duo/LDAPProxy.pm b/perl/lib/Wallet/Object/Duo/LDAPProxy.pm
new file mode 100644
index 0000000..cd32523
--- /dev/null
+++ b/perl/lib/Wallet/Object/Duo/LDAPProxy.pm
@@ -0,0 +1,202 @@
+# Wallet::Object::Duo::LDAPProxy -- Duo auth proxy integration for LDAP
+#
+# Written by Jon Robertson <jonrober@stanford.edu>
+# Copyright 2014
+#     The Board of Trustees of the Leland Stanford Junior University
+#
+# See LICENSE for licensing terms.
+
+##############################################################################
+# Modules and declarations
+##############################################################################
+
+package Wallet::Object::Duo::LDAPProxy;
+require 5.006;
+
+use strict;
+use warnings;
+use vars qw(@ISA $VERSION);
+
+use JSON;
+use Net::Duo::Admin;
+use Net::Duo::Admin::Integration;
+use Perl6::Slurp qw(slurp);
+use Wallet::Config ();
+use Wallet::Object::Duo;
+
+@ISA = qw(Wallet::Object::Duo);
+
+# This version should be increased on any code change to this module.  Always
+# use two digits for the minor version with a leading zero if necessary so
+# that it will sort properly.
+$VERSION = '0.01';
+
+##############################################################################
+# Core methods
+##############################################################################
+
+# Override create to provide the specific Duo integration type that will be
+# used in the remote Duo record.
+sub create {
+    my ($class, $type, $name, $schema, $creator, $host, $time) = @_;
+
+    $time ||= time;
+    my $self = $class->SUPER::create ($type, $name, $schema, $creator, $host,
+                                      $time, 'ldap');
+    return $self;
+}
+
+# Override get to output the data in a specific format used for Duo LDAP
+# integration
+sub get {
+    my ($self, $user, $host, $time) = @_;
+    $time ||= time;
+
+    # Check that the object isn't locked.
+    my $id = $self->{type} . ':' . $self->{name};
+    if ($self->flag_check ('locked')) {
+        $self->error ("cannot get $id: object is locked");
+        return;
+    }
+
+    # Retrieve the integration from Duo.
+    my $key;
+    eval {
+        my %search = (du_name => $self->{name});
+        my $row = $self->{schema}->resultset ('Duo')->find (\%search);
+        $key = $row->get_column ('du_key');
+    };
+    if ($@) {
+        $self->error ($@);
+        return;
+    }
+    my $integration = Net::Duo::Admin::Integration->new ($self->{duo}, $key);
+
+    # We also need the admin server name, which we can get from the Duo object
+    # configuration with a bit of JSON decoding.
+    my $json = JSON->new->utf8 (1)->relaxed (1);
+    my $config = $json->decode (scalar slurp $Wallet::Config::DUO_KEY_FILE);
+
+    # Construct the returned file.
+    my $output = "[ldap_server_challenge]\n";
+    $output .= "ikey     = $key\n";
+    $output .= 'skey     = ' . $integration->secret_key . "\n";
+    $output .= "api_host = $config->{api_hostname}\n";
+
+    # Log the action and return.
+    $self->log_action ('get', $user, $host, $time);
+    return $output;
+}
+
+1;
+__END__
+
+##############################################################################
+# Documentation
+##############################################################################
+
+=for stopwords
+Allbery Duo integration DBH keytab
+
+=head1 NAME
+
+Wallet::Object::Duo::LDAPProxy -- Duo auth proxy integration for LDAP
+
+=head1 SYNOPSIS
+
+    my @name = qw(duo-ldap host.example.com);
+    my @trace = ($user, $host, time);
+    my $object = Wallet::Object::Duo::LDAPProxy->create (@name, $schema, @trace);
+    my $config = $object->get (@trace);
+    $object->destroy (@trace);
+
+=head1 DESCRIPTION
+
+Wallet::Object::Duo::LDAPProxy is a representation of Duo
+integrations with the wallet, specifically to output Duo integrations
+in a format that can easily be pulled into configuring the Duo
+Authentication Proxy for LDAP. It implements the wallet object API
+and provides the necessary glue to create a Duo integration, return a
+configuration file containing the key and API information for that
+integration, and delete the integration from Duo when the wallet object
+is destroyed.
+
+The integration information is always returned in the configuration file
+format expected by the Authentication Proxy for Duo in configuring it
+for LDAP.
+
+This object can be retrieved repeatedly without changing the secret key,
+matching Duo's native behavior with integrations.  To change the keys of
+the integration, delete it and recreate it.
+
+To use this object, at least one configuration parameter must be set.  See
+L<Wallet::Config> for details on supported configuration parameters and
+information about how to set wallet configuration.
+
+=head1 METHODS
+
+This object mostly inherits from Wallet::Object::Duo.  See the
+documentation for that class for all generic methods.  Below are only
+those methods that are overridden or behave specially for this
+implementation.
+
+=over 4
+
+=item create(TYPE, NAME, DBH, PRINCIPAL, HOSTNAME [, DATETIME])
+
+This will override the Wallet::Object::Duo class with the information
+needed to create a specific integration type in Duo.  It creates a new
+object with the given TYPE and NAME (TYPE is normally C<duo-ldap> and
+must be for the rest of the wallet system to use the right class, but
+this module doesn't check for ease of subclassing), using DBH as the
+handle to the wallet metadata database.  PRINCIPAL, HOSTNAME, and
+DATETIME are stored as history information.  PRINCIPAL should be the
+user who is creating the object.  If DATETIME isn't given, the current
+time is used.
+
+When a new Duo integration object is created, a new integration will be
+created in the configured Duo account and the integration key will be
+stored in the wallet object.  If the integration already exists, create()
+will fail.
+
+If create() fails, it throws an exception.
+
+=item get(PRINCIPAL, HOSTNAME [, DATETIME])
+
+Retrieves the configuration information for the Duo integration and
+returns that information in the format expected by the configuration file
+for the Duo UNIX integration.  Returns undef on failure.  The caller
+should call error() to get the error message if get() returns undef.
+
+The returned configuration look look like:
+
+    [ldap_server_challenge]
+    ikey     = <integration-key>
+    skey     = <secret-key>
+    api_host = <api-hostname>
+
+The C<host> parameter will be taken from the configuration file pointed
+to by the DUO_KEY_FILE configuration variable.
+
+PRINCIPAL, HOSTNAME, and DATETIME are stored as history information.
+PRINCIPAL should be the user who is downloading the keytab.  If DATETIME
+isn't given, the current time is used.
+
+=back
+
+=head1 LIMITATIONS
+
+Only one Duo account is supported for a given wallet implementation.
+
+=head1 SEE ALSO
+
+Net::Duo(3), Wallet::Config(3), Wallet::Object::Duo(3), wallet-backend(8)
+
+This module is part of the wallet system.  The current version is
+available from L<http://www.eyrie.org/~eagle/software/wallet/>.
+
+=head1 AUTHORS
+
+Jon Robertson <jonrober@stanford.edu>
+
+=cut
diff --git a/perl/lib/Wallet/Object/Duo/PAM.pm b/perl/lib/Wallet/Object/Duo/PAM.pm
new file mode 100644
index 0000000..6f90ba1
--- /dev/null
+++ b/perl/lib/Wallet/Object/Duo/PAM.pm
@@ -0,0 +1,205 @@
+# Wallet::Object::Duo::PAM -- Duo PAM int. object implementation for wallet
+#
+# Written by Russ Allbery <eagle@eyrie.org>
+#            Jon Robertson <jonrober@stanford.edu>
+# Copyright 2014
+#     The Board of Trustees of the Leland Stanford Junior University
+#
+# See LICENSE for licensing terms.
+
+##############################################################################
+# Modules and declarations
+##############################################################################
+
+package Wallet::Object::Duo::PAM;
+require 5.006;
+
+use strict;
+use warnings;
+use vars qw(@ISA $VERSION);
+
+use JSON;
+use Net::Duo::Admin;
+use Net::Duo::Admin::Integration;
+use Perl6::Slurp qw(slurp);
+use Wallet::Config ();
+use Wallet::Object::Duo;
+
+@ISA = qw(Wallet::Object::Duo);
+
+# This version should be increased on any code change to this module.  Always
+# use two digits for the minor version with a leading zero if necessary so
+# that it will sort properly.
+$VERSION = '0.01';
+
+##############################################################################
+# Core methods
+##############################################################################
+
+# Override create to provide the specific Duo integration type that will be
+# used in the remote Duo record.
+sub create {
+    my ($class, $type, $name, $schema, $creator, $host, $time) = @_;
+
+    $time ||= time;
+    my $self = $class->SUPER::create ($type, $name, $schema, $creator, $host,
+                                      $time, 'unix');
+    return $self;
+}
+
+# Override get to output the data in a specific format used by Duo's PAM
+# module.
+sub get {
+    my ($self, $user, $host, $time) = @_;
+    $time ||= time;
+
+    # Check that the object isn't locked.
+    my $id = $self->{type} . ':' . $self->{name};
+    if ($self->flag_check ('locked')) {
+        $self->error ("cannot get $id: object is locked");
+        return;
+    }
+
+    # Retrieve the integration from Duo.
+    my $key;
+    eval {
+        my %search = (du_name => $self->{name});
+        my $row = $self->{schema}->resultset ('Duo')->find (\%search);
+        $key = $row->get_column ('du_key');
+    };
+    if ($@) {
+        $self->error ($@);
+        return;
+    }
+    my $integration = Net::Duo::Admin::Integration->new ($self->{duo}, $key);
+
+    # We also need the admin server name, which we can get from the Duo object
+    # configuration with a bit of JSON decoding.
+    my $json = JSON->new->utf8 (1)->relaxed (1);
+    my $config = $json->decode (scalar slurp $Wallet::Config::DUO_KEY_FILE);
+
+    # Construct the returned file.
+    my $output = "[duo]\n";
+    $output .= "ikey = $key\n";
+    $output .= 'skey = ' . $integration->secret_key . "\n";
+    $output .= "host = $config->{api_hostname}\n";
+
+    # Log the action and return.
+    $self->log_action ('get', $user, $host, $time);
+    return $output;
+}
+
+1;
+__END__
+
+##############################################################################
+# Documentation
+##############################################################################
+
+=for stopwords
+Allbery Duo integration DBH keytab
+
+=head1 NAME
+
+Wallet::Object::Duo::PAM -- Duo PAM int. object implementation for wallet
+
+=head1 SYNOPSIS
+
+    my @name = qw(duo-pam host.example.com);
+    my @trace = ($user, $host, time);
+    my $object = Wallet::Object::Duo::PAM->create (@name, $schema, @trace);
+    my $config = $object->get (@trace);
+    $object->destroy (@trace);
+
+=head1 DESCRIPTION
+
+Wallet::Object::Duo::PAM is a representation of Duo integrations with
+the wallet, specifically to output Duo integrations in a format that
+can easily be pulled into configuring the Duo PAM interface.  It
+implements the wallet object API and provides the necessary glue to
+create a Duo integration, return a configuration file containing the key
+and API information for that integration, and delete the integration from
+Duo when the wallet object is destroyed.
+
+The integration information is always returned in the configuration file
+format expected by the Duo UNIX integration.  The results of retrieving
+this object will be text, suitable for putting in the UNIX integration
+configuration file, containing the integration key, secret key, and admin
+hostname for that integration.
+
+This object can be retrieved repeatedly without changing the secret key,
+matching Duo's native behavior with integrations.  To change the keys of
+the integration, delete it and recreate it.
+
+To use this object, at least one configuration parameter must be set.  See
+L<Wallet::Config> for details on supported configuration parameters and
+information about how to set wallet configuration.
+
+=head1 METHODS
+
+This object mostly inherits from Wallet::Object::Duo.  See the
+documentation for that class for all generic methods.  Below are only
+those methods that are overridden or behave specially for this
+implementation.
+
+=over 4
+
+=item create(TYPE, NAME, DBH, PRINCIPAL, HOSTNAME [, DATETIME])
+
+This will override the Wallet::Object::Duo class with the information
+needed to create a specific integration type in Duo.  It creates a new
+object with the given TYPE and NAME (TYPE is normally C<duo-pam> and must
+be for the rest of the wallet system to use the right class, but this
+module doesn't check for ease of subclassing), using DBH as the handle
+to the wallet metadata database.  PRINCIPAL, HOSTNAME, and DATETIME are
+stored as history information.  PRINCIPAL should be the user who is
+creating the object.  If DATETIME isn't given, the current time is
+used.
+
+When a new Duo integration object is created, a new integration will be
+created in the configured Duo account and the integration key will be
+stored in the wallet object.  If the integration already exists, create()
+will fail.
+
+If create() fails, it throws an exception.
+
+=item get(PRINCIPAL, HOSTNAME [, DATETIME])
+
+Retrieves the configuration information for the Duo integration and
+returns that information in the format expected by the configuration file
+for the Duo UNIX integration.  Returns undef on failure.  The caller
+should call error() to get the error message if get() returns undef.
+
+The returned configuration look look like:
+
+    [duo]
+    ikey = <integration-key>
+    skey = <secret-key>
+    host = <api-hostname>
+
+The C<host> parameter will be taken from the configuration file pointed
+to by the DUO_KEY_FILE configuration variable.
+
+PRINCIPAL, HOSTNAME, and DATETIME are stored as history information.
+PRINCIPAL should be the user who is downloading the keytab.  If DATETIME
+isn't given, the current time is used.
+
+=back
+
+=head1 LIMITATIONS
+
+Only one Duo account is supported for a given wallet implementation.
+
+=head1 SEE ALSO
+
+Net::Duo(3), Wallet::Config(3), Wallet::Object::Duo(3), wallet-backend(8)
+
+This module is part of the wallet system.  The current version is
+available from L<http://www.eyrie.org/~eagle/software/wallet/>.
+
+=head1 AUTHORS
+
+Russ Allbery <eagle@eyrie.org>
+Jon Robertson <eagle@eyrie.org>
+
+=cut
diff --git a/perl/lib/Wallet/Object/Duo/RadiusProxy.pm b/perl/lib/Wallet/Object/Duo/RadiusProxy.pm
new file mode 100644
index 0000000..2a29dec
--- /dev/null
+++ b/perl/lib/Wallet/Object/Duo/RadiusProxy.pm
@@ -0,0 +1,204 @@
+# Wallet::Object::Duo::RadiusProxy -- Duo auth proxy integration for radius
+#
+# Written by Jon Robertson <jonrober@stanford.edu>
+# Copyright 2014
+#     The Board of Trustees of the Leland Stanford Junior University
+#
+# See LICENSE for licensing terms.
+
+##############################################################################
+# Modules and declarations
+##############################################################################
+
+package Wallet::Object::Duo::RadiusProxy;
+require 5.006;
+
+use strict;
+use warnings;
+use vars qw(@ISA $VERSION);
+
+use JSON;
+use Net::Duo::Admin;
+use Net::Duo::Admin::Integration;
+use Perl6::Slurp qw(slurp);
+use Wallet::Config ();
+use Wallet::Object::Duo;
+
+@ISA = qw(Wallet::Object::Duo);
+
+# This version should be increased on any code change to this module.  Always
+# use two digits for the minor version with a leading zero if necessary so
+# that it will sort properly.
+$VERSION = '0.01';
+
+##############################################################################
+# Core methods
+##############################################################################
+
+# Override create to provide the specific Duo integration type that will be
+# used in the remote Duo record.
+sub create {
+    my ($class, $type, $name, $schema, $creator, $host, $time) = @_;
+
+    $time ||= time;
+    my $self = $class->SUPER::create ($type, $name, $schema, $creator, $host,
+                                      $time, 'radius');
+    return $self;
+}
+
+# Override get to output the data in a specific format used for Duo radius
+# integration
+sub get {
+    my ($self, $user, $host, $time) = @_;
+    $time ||= time;
+
+    # Check that the object isn't locked.
+    my $id = $self->{type} . ':' . $self->{name};
+    if ($self->flag_check ('locked')) {
+        $self->error ("cannot get $id: object is locked");
+        return;
+    }
+
+    # Retrieve the integration from Duo.
+    my $key;
+    eval {
+        my %search = (du_name => $self->{name});
+        my $row = $self->{schema}->resultset ('Duo')->find (\%search);
+        $key = $row->get_column ('du_key');
+    };
+    if ($@) {
+        $self->error ($@);
+        return;
+    }
+    my $integration = Net::Duo::Admin::Integration->new ($self->{duo}, $key);
+
+    # We also need the admin server name, which we can get from the Duo object
+    # configuration with a bit of JSON decoding.
+    my $json = JSON->new->utf8 (1)->relaxed (1);
+    my $config = $json->decode (scalar slurp $Wallet::Config::DUO_KEY_FILE);
+
+    # Construct the returned file.
+    my $output = "[radius_server_challenge]\n";
+    $output .= "ikey     = $key\n";
+    $output .= 'skey     = ' . $integration->secret_key . "\n";
+    $output .= "api_host = $config->{api_hostname}\n";
+    $output .= "client   = radius_client\n";
+
+    # Log the action and return.
+    $self->log_action ('get', $user, $host, $time);
+    return $output;
+}
+
+1;
+__END__
+
+##############################################################################
+# Documentation
+##############################################################################
+
+=for stopwords
+Allbery Duo integration DBH keytab
+
+=head1 NAME
+
+Wallet::Object::Duo::RadiusProxy -- Duo auth proxy integration for radius
+
+=head1 SYNOPSIS
+
+    my @name = qw(duo-radius host.example.com);
+    my @trace = ($user, $host, time);
+    my $object = Wallet::Object::Duo::RadiusProxy->create (@name, $schema, @trace);
+    my $config = $object->get (@trace);
+    $object->destroy (@trace);
+
+=head1 DESCRIPTION
+
+Wallet::Object::Duo::RadiusProxy is a representation of Duo
+integrations with the wallet, specifically to output Duo integrations
+in a format that can easily be pulled into configuring the Duo
+Authentication Proxy for Radius. It implements the wallet object API
+and provides the necessary glue to create a Duo integration, return a
+configuration file containing the key and API information for that
+integration, and delete the integration from Duo when the wallet object
+is destroyed.
+
+The integration information is always returned in the configuration file
+format expected by the Authentication Proxy for Duo in configuring it
+for Radius.
+
+This object can be retrieved repeatedly without changing the secret key,
+matching Duo's native behavior with integrations.  To change the keys of
+the integration, delete it and recreate it.
+
+To use this object, at least one configuration parameter must be set.  See
+L<Wallet::Config> for details on supported configuration parameters and
+information about how to set wallet configuration.
+
+=head1 METHODS
+
+This object mostly inherits from Wallet::Object::Duo.  See the
+documentation for that class for all generic methods.  Below are only
+those methods that are overridden or behave specially for this
+implementation.
+
+=over 4
+
+=item create(TYPE, NAME, DBH, PRINCIPAL, HOSTNAME [, DATETIME])
+
+This will override the Wallet::Object::Duo class with the information
+needed to create a specific integration type in Duo.  It creates a new
+object with the given TYPE and NAME (TYPE is normally C<duo-radius> and
+must be for the rest of the wallet system to use the right class, but
+this module doesn't check for ease of subclassing), using DBH as the
+handle to the wallet metadata database.  PRINCIPAL, HOSTNAME, and
+DATETIME are stored as history information.  PRINCIPAL should be the
+user who is creating the object.  If DATETIME isn't given, the current
+time is used.
+
+When a new Duo integration object is created, a new integration will be
+created in the configured Duo account and the integration key will be
+stored in the wallet object.  If the integration already exists, create()
+will fail.
+
+If create() fails, it throws an exception.
+
+=item get(PRINCIPAL, HOSTNAME [, DATETIME])
+
+Retrieves the configuration information for the Duo integration and
+returns that information in the format expected by the configuration file
+for the Duo UNIX integration.  Returns undef on failure.  The caller
+should call error() to get the error message if get() returns undef.
+
+The returned configuration look look like:
+
+    [radius_server_challenge]
+    ikey     = <integration-key>
+    skey     = <secret-key>
+    api_host = <api-hostname>
+    client   = radius_client
+
+The C<host> parameter will be taken from the configuration file pointed
+to by the DUO_KEY_FILE configuration variable.
+
+PRINCIPAL, HOSTNAME, and DATETIME are stored as history information.
+PRINCIPAL should be the user who is downloading the keytab.  If DATETIME
+isn't given, the current time is used.
+
+=back
+
+=head1 LIMITATIONS
+
+Only one Duo account is supported for a given wallet implementation.
+
+=head1 SEE ALSO
+
+Net::Duo(3), Wallet::Config(3), Wallet::Object::Duo(3), wallet-backend(8)
+
+This module is part of the wallet system.  The current version is
+available from L<http://www.eyrie.org/~eagle/software/wallet/>.
+
+=head1 AUTHORS
+
+Jon Robertson <jonrober@stanford.edu>
+
+=cut