diff options
Diffstat (limited to 'perl/lib')
| -rw-r--r-- | perl/lib/Wallet/ACL/External.pm | 197 | ||||
| -rw-r--r-- | perl/lib/Wallet/Config.pm | 35 |
2 files changed, 230 insertions, 2 deletions
diff --git a/perl/lib/Wallet/ACL/External.pm b/perl/lib/Wallet/ACL/External.pm new file mode 100644 index 0000000..da013aa --- /dev/null +++ b/perl/lib/Wallet/ACL/External.pm @@ -0,0 +1,197 @@ +# Wallet::ACL::External -- Wallet external ACL verifier +# +# Written by Russ Allbery <eagle@eyrie.org> +# Copyright 2016 Russ Allbery <eagle@eyrie.org> +# +# See LICENSE for licensing terms. + +############################################################################## +# Modules and declarations +############################################################################## + +package Wallet::ACL::External; +require 5.008; + +use strict; +use warnings; +use vars qw(@ISA $VERSION); + +use Wallet::ACL::Base; +use Wallet::Config; + +@ISA = qw(Wallet::ACL::Base); + +# This version should be increased on any code change to this module. Always +# use two digits for the minor version with a leading zero if necessary so +# that it will sort properly. +$VERSION = '0.01'; + +############################################################################## +# Interface +############################################################################## + +# Creates a new persistent verifier. This just checks if the configuration +# is in place. +sub new { + my $type = shift; + unless ($Wallet::Config::EXTERNAL_COMMAND) { + die "external ACL support not configured\n"; + } + my $self = {}; + bless ($self, $type); + return $self; +} + +# The most trivial ACL verifier. Returns true if the provided principal +# matches the ACL. +sub check { + my ($self, $principal, $acl) = @_; + unless ($principal) { + $self->error ('no principal specified'); + return; + } + my @args = split (' ', $acl); + unshift @args, $principal; + my $pid = open (EXTERNAL, '-|'); + if (not defined $pid) { + $self->error ("cannot fork: $!"); + return; + } elsif ($pid == 0) { + unless (open (STDERR, '>&STDOUT')) { + warn "wallet: cannot dup stdout: $!\n"; + exit 1; + } + unless (exec ($Wallet::Config::EXTERNAL_COMMAND, @args)) { + warn "wallet: cannot run $Wallet::Config::EXTERNAL_COMMAND: $!\n"; + exit 1; + } + } + local $_; + my @output = <EXTERNAL>; + close EXTERNAL; + if ($? == 0) { + return 1; + } else { + if (@output) { + $self->error ($output[0]); + return; + } else { + return 0; + } + } +} + +1; +__END__ + +############################################################################## +# Documentation +############################################################################## + +=for stopwords +ACL Allbery verifier + +=head1 NAME + +Wallet::ACL::External - Wallet ACL verifier using an external command + +=head1 SYNOPSIS + + my $verifier = Wallet::ACL::External->new; + my $status = $verifier->check ($principal, $acl); + if (not defined $status) { + die "Something failed: ", $verifier->error, "\n"; + } elsif ($status) { + print "Access granted\n"; + } else { + print "Access denied\n"; + } + +=head1 DESCRIPTION + +Wallet::ACL::External runs an external command to determine whether access is +granted. The command configured via $EXTERNAL_COMMAND in L<Wallet::Config> +will be run. The first argument to the command will be the principal +requesting access. The identifier of the ACL will be split on whitespace and +passed in as the remaining arguments to this command. + +No other arguments are passed to the command, but the command will have access +to all of the remctl environment variables seen by the wallet server (such as +REMOTE_USER). For a full list of environment variables, see +L<remctld(8)/ENVIRONMENT>. + +The external command should exit with a non-zero status but no output to +indicate a normal failure to satisfy the ACL. Any output will be treated as +an error. + +=head1 METHODS + +=over 4 + +=item new() + +Creates a new ACL verifier. For this verifier, this just confirms that +the wallet configuration sets an external command. + +=item check(PRINCIPAL, ACL) + +Returns true if the external command returns success when run with that +PRINCIPAL and ACL. ACL will be split on whitespace and passed as multiple +arguments. So, for example, the ACL C<external mdbset shell> will, when +triggered by a request from rra@EXAMPLE.COM, result in the command: + + $Wallet::Config::EXTERNAL_COMMAND rra@EXAMPLE.COM mdbset shell + +=item error() + +Returns the error if check() returned undef. + +=back + +=head1 DIAGNOSTICS + +The new() method may fail with one of the following exceptions: + +=over 4 + +=item external ACL support not configured + +The required configuration parameters were not set. See L<Wallet::Config> +for the required configuration parameters and how to set them. + +=back + +Verifying an external ACL may fail with the following errors (returned by +the error() method): + +=over 4 + +=item cannot fork: %s + +The attempt to fork in order to execute the external ACL verifier +command failed, probably due to a lack of system resources. + +=item no principal specified + +The PRINCIPAL parameter to check() was undefined or the empty string. + +=back + +In addition, if the external command fails and produces some output, +that will be considered a failure and the first line of its output will +be returned as the error message. The external command should exit +with a non-zero status but no error to indicate a normal failure. + +=head1 SEE ALSO + +remctld(8), Wallet::ACL(3), Wallet::ACL::Base(3), Wallet::Config(3), +wallet-backend(8) + +This module is part of the wallet system. The current version is +available from L<http://www.eyrie.org/~eagle/software/wallet/>. + +=head1 AUTHOR + +Russ Allbery <eagle@eyrie.org> + +=cut diff --git a/perl/lib/Wallet/Config.pm b/perl/lib/Wallet/Config.pm index b3e1931..98b5dc9 100644 --- a/perl/lib/Wallet/Config.pm +++ b/perl/lib/Wallet/Config.pm @@ -1,7 +1,8 @@ # Wallet::Config -- Configuration handling for the wallet server. # # Written by Russ Allbery <eagle@eyrie.org> -# Copyright 2007, 2008, 2010, 2013, 2014 +# Copyright 2016 Russ Allbery <eagle@eyrie.org> +# Copyright 2007, 2008, 2010, 2013, 2014, 2015 # The Board of Trustees of the Leland Stanford Junior University # # See LICENSE for licensing terms. @@ -16,7 +17,7 @@ use vars qw($PATH $VERSION); # This version should be increased on any code change to this module. Always # use two digits for the minor version with a leading zero if necessary so # that it will sort properly. -$VERSION = '0.05'; +$VERSION = '0.06'; # Path to the config file to load. $PATH = $ENV{WALLET_CONFIG} || '/etc/wallet/wallet.conf'; @@ -540,6 +541,36 @@ our $WAKEYRING_PURGE_INTERVAL = 60 * 60 * 24 * 90; =back +=head1 EXTERNAL ACL CONFIGURATION + +This configuration variable is only needed if you intend to use the +C<external> ACL type (the Wallet::ACL::External class). This ACL type +runs an external command to determine if access is granted. + +=over 4 + +=item EXTERNAL_COMMAND + +Path to the command to run to determine whether access is granted. The +first argument to the command will be the principal requesting access. +The identifier of the ACL will be split on whitespace and passed in as the +remaining arguments to this command. + +No other arguments are passed to the command, but the command will have +access to all of the remctl environment variables seen by the wallet +server (such as REMOTE_USER). For a full list of environment variables, +see L<remctld(8)/ENVIRONMENT>. + +The external command should exit with a non-zero status but no output to +indicate a normal failure to satisfy the ACL. Any output will be treated +as an error. + +=cut + +our $EXTERNAL_COMMAND; + +=back + =head1 LDAP ACL CONFIGURATION These configuration variables are only needed if you intend to use the |