From 7c2e7ad410e59d6f0c21d76859656b8aa8838ecb Mon Sep 17 00:00:00 2001 From: Joe Atzberger Date: Tue, 30 Jun 2009 09:14:50 -0500 Subject: [PATCH] LDAP overhaul Allow replicate and update to be zero. Break out logic into separate subs. Do only one bind attempt depending on setting, instead of necessarily failing first before trying auth_by_bind. POD added for active directory and to document permutations of behavior given different conditions. Fixed mistaken debug lines that called "print STDERR printf ...", i.e. printed the line to output and "1" to the error log. Added principal_name feature for generating bind user from Koha userid. Signed-off-by: Galen Charlton --- C4/Auth_with_ldap.pm | 216 ++++++++++++++++++++++++++++++------------- 1 file changed, 154 insertions(+), 62 deletions(-) diff --git a/C4/Auth_with_ldap.pm b/C4/Auth_with_ldap.pm index cbe0b51ab7..08a4353025 100644 --- a/C4/Auth_with_ldap.pm +++ b/C4/Auth_with_ldap.pm @@ -18,6 +18,7 @@ package C4::Auth_with_ldap; # Suite 330, Boston, MA 02111-1307 USA use strict; +# use warnings; almost? use Digest::MD5 qw(md5_base64); use C4::Debug; @@ -31,7 +32,7 @@ use vars qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $debug); BEGIN { require Exporter; - $VERSION = 3.03; # set the version for version checking + $VERSION = 3.10; # set the version for version checking @ISA = qw(Exporter); @EXPORT = qw( checkpw_ldap ); } @@ -54,7 +55,7 @@ my $prefhost = $ldap->{hostname} or die ldapserver_error('hostname'); my $base = $ldap->{base} or die ldapserver_error('base'); $ldapname = $ldap->{user} ; $ldappassword = $ldap->{pass} ; -our %mapping = %{$ldap->{mapping}} or die ldapserver_error('mapping'); +our %mapping = %{$ldap->{mapping}} || (); # or die ldapserver_error('mapping'); my @mapkeys = keys %mapping; $debug and print STDERR "Got ", scalar(@mapkeys), " ldap mapkeys ( total ): ", join ' ', @mapkeys, "\n"; @mapkeys = grep {defined $mapping{$_}->{is}} @mapkeys; @@ -62,8 +63,8 @@ $debug and print STDERR "Got ", scalar(@mapkeys), " ldap mapkeys (populated): ", my %config = ( anonymous => ($ldapname and $ldappassword) ? 0 : 1, - replicate => $ldap->{replicate} || 1, # add from LDAP to Koha database for new user - update => $ldap->{update} || 1, # update from LDAP to Koha database for existing user + replicate => defined($ldap->{replicate}) ? $ldap->{replicate} : 1, # add from LDAP to Koha database for new user + update => defined($ldap->{update} ) ? $ldap->{update} : 1, # update from LDAP to Koha database for existing user ); sub description ($) { @@ -73,15 +74,14 @@ sub description ($) { . "# " . $result->error_text . "\n"; } -sub checkpw_ldap { - my ($dbh, $userid, $password) = @_; - my $db = Net::LDAP->new([$prefhost]); - #$debug and $db->debug(5); +sub search_method { + my $db = shift or return; + my $userid = shift or return; my $uid_field = $mapping{userid}->{is} or die ldapserver_error("mapping for 'userid'"); my $filter = Net::LDAP::Filter->new("$uid_field=$userid") or die "Failed to create new Net::LDAP::Filter"; my $res = ($config{anonymous}) ? $db->bind : $db->bind($ldapname, password=>$ldappassword); if ($res->code) { # connection refused - warn "LDAP bind failed as $ldapname: " . description($res); + warn "LDAP bind failed as ldapuser " . ($ldapname || '[ANONYMOUS]') . ": " . description($res); return 0; } my $search = $db->search( @@ -98,36 +98,61 @@ sub checkpw_ldap { warn sprintf("LDAP Auth rejected : %s gets %d hits\n", $filter->as_string, $count); return 0; } + return $search; +} - my $userldapentry = $search->shift_entry; +sub checkpw_ldap { + my ($dbh, $userid, $password) = @_; + my @hosts = split(',', $prefhost); + my $db = Net::LDAP->new(\@hosts); + #$debug and $db->debug(5); + my $userldapentry; if ( $ldap->{auth_by_bind} ) { - my $user_ldapname = $userldapentry->dn(); - my $user_db = Net::LDAP->new( [$prefhost] ); - $res = $user_db->bind( $user_ldapname, password => $password ); - if ( $res->code ) { - $debug and warn "Bind as user failed ". description( $res ); - return 0; - } + my $principal_name = $ldap->{principal_name}; + if ($principal_name and $principal_name =~ /\%/) { + $principal_name = sprintf($principal_name,$userid); + } else { + $principal_name = $userid; + } + my $res = $db->bind( $principal_name, password => $password ); + if ( $res->code ) { + $debug and warn "LDAP bind failed as kohauser $principal_name: ". description($res); + return 0; + } } else { + my $search = search_method($db, $userid) or return 0; # warnings are in the sub + $userldapentry = $search->shift_entry; my $cmpmesg = $db->compare( $userldapentry, attr=>'userpassword', value => $password ); if ($cmpmesg->code != 6) { warn "LDAP Auth rejected : invalid password for user '$userid'. " . description($cmpmesg); return 0; } } - unless ($config{update} or $config{replicate}) { - return 1; - } - my %borrower = ldap_entry_2_hash($userldapentry,$userid); - $debug and print STDERR "checkpw_ldap received \%borrower w/ " . keys(%borrower), " keys: ", join(' ', keys %borrower), "\n"; - my ($borrowernumber,$cardnumber,$savedpw); - ($borrowernumber,$cardnumber,$userid,$savedpw) = exists_local($userid); - if ($borrowernumber) { - ($config{update} ) and my $c2 = &update_local($userid,$password,$borrowernumber,\%borrower) || ''; - ($cardnumber eq $c2) or warn "update_local returned cardnumber '$c2' instead of '$cardnumber'"; - } else { - ($config{replicate}) and $borrowernumber = AddMember(%borrower); - } + + # To get here, LDAP has accepted our user's login attempt. + # But we still have work to do. See perldoc below for detailed breakdown. + + my (%borrower); + my ($borrowernumber,$cardnumber,$local_userid,$savedpw) = exists_local($userid); + + if (( $borrowernumber and $config{update} ) or + (!$borrowernumber and $config{replicate}) ) { + %borrower = ldap_entry_2_hash($userldapentry,$userid); + $debug and print STDERR "checkpw_ldap received \%borrower w/ " . keys(%borrower), " keys: ", join(' ', keys %borrower), "\n"; + } + + if ($borrowernumber) { + if ($config{update}) { # A1, B1 + my $c2 = &update_local($local_userid,$password,$borrowernumber,\%borrower) || ''; + ($cardnumber eq $c2) or warn "update_local returned cardnumber '$c2' instead of '$cardnumber'"; + } else { # C1, D1 + # maybe update just the password? + } + } elsif ($config{replicate}) { # A2, C2 + $borrowernumber = AddMember(%borrower) or die "AddMember failed"; + } else { + return 0; # B2, D2 + } return(1, $cardnumber); } @@ -149,7 +174,6 @@ sub ldap_entry_2_hash ($$) { } } my $x = $userldapentry->{attrs} or return undef; - my $key; foreach (keys %$x) { $memberhash{$_} = join ' ', @{$x->{$_}}; $debug and print STDERR sprintf("building \$memberhash{%s} = ", $_, join(' ', @{$x->{$_}})), "\n"; @@ -158,7 +182,7 @@ sub ldap_entry_2_hash ($$) { "Referencing \%mapping with ", scalar(keys %mapping), " keys\n"; foreach my $key (keys %mapping) { my $data = $memberhash{$mapping{$key}->{is}}; - $debug and print STDERR printf "mapping %20s ==> %-20s (%s)\n", $key, $mapping{$key}->{is}, $data; + $debug and printf STDERR "mapping %20s ==> %-20s (%s)\n", $key, $mapping{$key}->{is}, $data; unless (defined $data) { $data = $mapping{$key}->{content} || ''; # default or failsafe '' } @@ -178,16 +202,33 @@ sub exists_local($) { my $sth = $dbh->prepare("$select WHERE userid=?"); # was cardnumber=? $sth->execute($arg); - $debug and print STDERR printf "Userid '$arg' exists_local? %s\n", $sth->rows; + $debug and printf STDERR "Userid '$arg' exists_local? %s\n", $sth->rows; ($sth->rows == 1) and return $sth->fetchrow; $sth = $dbh->prepare("$select WHERE cardnumber=?"); $sth->execute($arg); - $debug and print STDERR printf "Cardnumber '$arg' exists_local? %s\n", $sth->rows; + $debug and printf STDERR "Cardnumber '$arg' exists_local? %s\n", $sth->rows; ($sth->rows == 1) and return $sth->fetchrow; return 0; } +sub _do_changepassword { + my ($userid, $borrowerid, $digest) = @_; + $debug and print STDERR "changing local password for borrowernumber=$borrowerid to '$digest'\n"; + changepassword($userid, $borrowerid, $digest); + + # Confirm changes + my $sth = C4::Context->dbh->prepare("SELECT password,cardnumber FROM borrowers WHERE borrowernumber=? "); + $sth->execute($borrowerid); + if ($sth->rows) { + my ($md5password, $cardnum) = $sth->fetchrow; + ($digest eq $md5password) and return $cardnum; + warn "Password mismatch after update to cardnumber=$cardnum (borrowernumber=$borrowerid)"; + return undef; + } + die "Unexpected error after password update to userid/borrowernumber: $userid / $borrowerid."; +} + sub update_local($$$$) { my $userid = shift or return undef; my $digest = md5_base64(shift) or return undef; @@ -209,20 +250,7 @@ sub update_local($$$$) { ); # MODIFY PASSWORD/LOGIN - # search borrowerid - $debug and print STDERR "changing local password for borrowernumber=$borrowerid to '$digest'\n"; - changepassword($userid, $borrowerid, $digest); - - # Confirm changes - $sth = $dbh->prepare("SELECT password,cardnumber FROM borrowers WHERE borrowernumber=? "); - $sth->execute($borrowerid); - if ($sth->rows) { - my ($md5password, $cardnum) = $sth->fetchrow; - ($digest eq $md5password) and return $cardnum; - warn "Password mismatch after update to cardnumber=$cardnum (borrowernumber=$borrowerid)"; - return undef; - } - die "Unexpected error after password update to userid/borrowernumber: $userid / $borrowerid."; + _do_changepassword($userid, $borrowerid, $digest); } 1; @@ -309,8 +337,6 @@ C4::Auth - Authenticates Koha users Where Null="NO", the field is required. -=cut - =head1 KOHA_CONF and field mapping Example XML stanza for LDAP configuration in KOHA_CONF. @@ -328,6 +354,8 @@ Example XML stanza for LDAP configuration in KOHA_CONF. 1 0 + %s@my_domain.com + @@ -349,8 +377,84 @@ is the column in mysql, with the "is" characteristic set to the LDAP attribute n between the element tags is taken as the default value. In this example, the default categorycode is "PT" (for patron). +=head1 CONFIGURATION + +Once a user has been accepted by the LDAP server, there are several possibilities for how Koha will behave, depending on +your configuration and the presence of a matching Koha user in your local DB: + + LOCAL_USER + OPTION UPDATE REPLICATE EXISTS? RESULT + A1 1 1 1 OK : We're updating them anyway. + A2 1 1 0 OK : We're adding them anyway. + B1 1 0 1 OK : We update them. + B2 1 0 0 FAIL: We cannot add new user. + C1 0 1 1 OK : We do nothing. (maybe should update password?) + C2 0 1 0 OK : We add the new user. + D1 0 0 1 OK : We do nothing. (maybe should update password?) + D2 0 0 0 FAIL: We cannot add new user. + +Note: failure here just means that Koha will fallback to checking the local DB. That is, a given user could login with +their LDAP password OR their local one. If this is a problem, then you should enable update and supply a mapping for +password. Then the local value will be updated at successful LDAP login and the passwords will be synced. + +If you choose NOT to update local users, the borrowers table will not be affected at all. +Note that this means that patron passwords may appear to change if LDAP is ever disabled, because +the local table never contained the LDAP values. + +=head2 auth_by_bind + +Binds as the user instead of retrieving their record. Recommended if update disabled. + +=head2 principal_name + +Provides an optional sprintf-style format for manipulating the userid before the bind. +Even though the userPrincipalName is one intended target, any uniquely identifying +attribute that the server allows to be used for binding could be used. + +Currently, principal_name only operates when auth_by_bind is enabled. + +=head2 Active Directory + +The auth_by_bind and principal_name settings are recommended for Active Directory. + +Under default Active Directory rules, we cannot determine the distinguishedName attribute from the Koha userid as reliably as +we would typically under openldap. Instead of: + + distinguishedName: CN=barnes.7,DC=my_company,DC=com + +We might get: + + distinguishedName: CN=Barnes\, Jim,OU=Test Accounts,OU=User Accounts,DC=my_company,DC=com + +Matching that would require us to know more info about the account (firstname, surname) and to include punctuation and whitespace +in Koha userids. But the userPrincipalName should be consistent, something like: + + userPrincipalName: barnes.7@my_company.com + +Therefore it is often easier to bind to Active Directory with userPrincipalName, effectively the +canonical email address for that user, or what it would be if email were enabled for them. If Koha userid values +will match the username portion of the userPrincipalName, and the domain suffix is the same for all users, then use principal_name +like this: + %s@core.my_company.com + +The user of the previous example, barnes.7, would then attempt to bind as: + barnes.7@core.my_company.com + +=head1 SEE ALSO + +CGI(3) + +Net::LDAP() + +XML::Simple() + +Digest::MD5(3) + +sprintf() + =cut +# For reference, here's an important difference in the data structure we rely on. # ======================================== # Using attrs instead of {asn}->attributes # ======================================== @@ -363,15 +467,3 @@ patron). # LDAP key: ->{ givenname} = ARRAY w/ 1 members. # LDAP key: ->{ givenname}->{Steve} = Steve # - -=head1 SEE ALSO - -CGI(3) - -Net::LDAP() - -XML::Simple() - -Digest::MD5(3) - -=cut -- 2.39.5