C4/Auth_with_ldap.pm

   1 package C4::Auth_with_ldap;
   2
   3 # Copyright 2000-2002 Katipo Communications
   4 #
   5 # This file is part of Koha.
   6 #
   7 # Koha is free software; you can redistribute it and/or modify it
   8 # under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # Koha is distributed in the hope that it will be useful, but
  13 # WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with Koha; if not, see <http://www.gnu.org/licenses>.
  19
  20 use strict;
  21 #use warnings; FIXME - Bug 2505
  22 use Carp;
  23
  24 use C4::Debug;
  25 use C4::Context;
  26 use C4::Members::Attributes;
  27 use C4::Members::AttributeTypes;
  28 use C4::Members::Messaging;
  29 use C4::Auth qw(checkpw_internal);
  30 use Koha::Patrons;
  31 use Koha::AuthUtils qw(hash_password);
  32 use List::MoreUtils qw( any );
  33 use Net::LDAP;
  34 use Net::LDAP::Filter;
  35
  36 use vars qw(@ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $debug);
  37
  38 BEGIN {
  39         require Exporter;
  40         @ISA    = qw(Exporter);
  41         @EXPORT = qw( checkpw_ldap );
  42 }
  43
  44 # Redefine checkpw_ldap:
  45 # connect to LDAP (named or anonymous)
  46 # ~ retrieves $userid from KOHA_CONF mapping
  47 # ~ then compares $password with userPassword
  48 # ~ then gets the LDAP entry
  49 # ~ and calls the memberadd if necessary
  50
  51 sub ldapserver_error {
  52         return sprintf('No ldapserver "%s" defined in KOHA_CONF: ' . $ENV{KOHA_CONF}, shift);
  53 }
  54
  55 use vars qw($mapping @ldaphosts $base $ldapname $ldappassword);
  56 my $context = C4::Context->new()        or die 'C4::Context->new failed';
  57 my $ldap = C4::Context->config("ldapserver") or die 'No "ldapserver" in server hash from KOHA_CONF: ' . $ENV{KOHA_CONF};
  58 my $prefhost  = $ldap->{hostname}       or die ldapserver_error('hostname');
  59 my $base      = $ldap->{base}           or die ldapserver_error('base');
  60 $ldapname     = $ldap->{user}           ;
  61 $ldappassword = $ldap->{pass}           ;
  62 our %mapping  = %{$ldap->{mapping}}; # FIXME dpavlin -- don't die because of || (); from 6eaf8511c70eb82d797c941ef528f4310a15e9f9
  63 my @mapkeys = keys %mapping;
  64 $debug and print STDERR "Got ", scalar(@mapkeys), " ldap mapkeys (  total  ): ", join ' ', @mapkeys, "\n";
  65 @mapkeys = grep {defined $mapping{$_}->{is}} @mapkeys;
  66 $debug and print STDERR "Got ", scalar(@mapkeys), " ldap mapkeys (populated): ", join ' ', @mapkeys, "\n";
  67
  68 my %categorycode_conversions;
  69 my $default_categorycode;
  70 if(defined $ldap->{categorycode_mapping}) {
  71     $default_categorycode = $ldap->{categorycode_mapping}->{default};
  72     foreach my $cat (@{$ldap->{categorycode_mapping}->{categorycode}}) {
  73         $categorycode_conversions{$cat->{value}} = $cat->{content};
  74     }
  75 }
  76
  77 my %config = (
  78     anonymous => defined ($ldap->{anonymous_bind}) ? $ldap->{anonymous_bind} : 1,
  79     replicate => defined($ldap->{replicate}) ? $ldap->{replicate} : 1,  #    add from LDAP to Koha database for new user
  80        update => defined($ldap->{update}   ) ? $ldap->{update}    : 1,  # update from LDAP to Koha database for existing user
  81 );
  82
  83 sub description {
  84         my $result = shift or return;
  85         return "LDAP error #" . $result->code
  86                         . ": " . $result->error_name . "\n"
  87                         . "# " . $result->error_text . "\n";
  88 }
  89
  90 sub search_method {
  91     my $db     = shift or return;
  92     my $userid = shift or return;
  93         my $uid_field = $mapping{userid}->{is} or die ldapserver_error("mapping for 'userid'");
  94         my $filter = Net::LDAP::Filter->new("$uid_field=$userid") or die "Failed to create new Net::LDAP::Filter";
  95         my $search = $db->search(
  96                   base => $base,
  97                 filter => $filter,
  98                 # attrs => ['*'],
  99     );
 100     die "LDAP search failed to return object : " . $search->error if $search->code;
 101
 102         my $count = $search->count;
 103         if ($search->code > 0) {
 104                 warn sprintf("LDAP Auth rejected : %s gets %d hits\n", $filter->as_string, $count) . description($search);
 105                 return 0;
 106         }
 107     if ($count == 0) {
 108         warn sprintf("LDAP Auth rejected : search with filter '%s' returns no hit\n", $filter->as_string);
 109         return 0;
 110     }
 111     return $search;
 112 }
 113
 114 sub checkpw_ldap {
 115     my ($dbh, $userid, $password) = @_;
 116     my @hosts = split(',', $prefhost);
 117     my $db = Net::LDAP->new(\@hosts);
 118     unless ( $db ) {
 119         warn "LDAP connexion failed";
 120         return 0;
 121     }
 122
 123         #$debug and $db->debug(5);
 124     my $userldapentry;
 125
 126     # first, LDAP authentication
 127     if ( $ldap->{auth_by_bind} ) {
 128         my $principal_name;
 129         if ( $config{anonymous} ) {
 130
 131             # Perform an anonymous bind
 132             my $res = $db->bind;
 133             if ( $res->code ) {
 134                 warn "Anonymous LDAP bind failed: " . description($res);
 135                 return 0;
 136             }
 137
 138             # Perform a LDAP search for the given username
 139             my $search = search_method( $db, $userid )
 140               or return 0;    # warnings are in the sub
 141             $userldapentry = $search->shift_entry;
 142             $principal_name = $userldapentry->dn;
 143         }
 144         else {
 145             $principal_name = $ldap->{principal_name};
 146             if ( $principal_name and $principal_name =~ /\%/ ) {
 147                 $principal_name = sprintf( $principal_name, $userid );
 148             }
 149             else {
 150                 $principal_name = $userid;
 151             }
 152         }
 153
 154         # Perform a LDAP bind for the given username using the matched DN
 155         my $res = $db->bind( $principal_name, password => $password );
 156         if ( $res->code ) {
 157             if ( $config{anonymous} ) {
 158                 # With anonymous_bind approach we can be sure we have found the correct user
 159                 # and that any 'code' response indicates a 'bad' user (be that blocked, banned
 160                 # or password changed). We should not fall back to local accounts in this case.
 161                 warn "LDAP bind failed as kohauser $userid: " . description($res);
 162                 return -1;
 163             } else {
 164                 # Without a anonymous_bind, we cannot be sure we are looking at a valid ldap user
 165                 # at all, and thus we should fall back to local logins to restore previous behaviour
 166                 # see bug 12831
 167                 warn "LDAP bind failed as kohauser $userid: " . description($res);
 168                 return 0;
 169             }
 170         }
 171         if ( !defined($userldapentry)
 172             && ( $config{update} or $config{replicate} ) )
 173         {
 174             my $search = search_method( $db, $userid ) or return 0;
 175             $userldapentry = $search->shift_entry;
 176         }
 177     } else {
 178         my $res = ($config{anonymous}) ? $db->bind : $db->bind($ldapname, password=>$ldappassword);
 179                 if ($res->code) {               # connection refused
 180                         warn "LDAP bind failed as ldapuser " . ($ldapname || '[ANONYMOUS]') . ": " . description($res);
 181                         return 0;
 182                 }
 183         my $search = search_method($db, $userid) or return 0;   # warnings are in the sub
 184         # Handle multiple branches. Same login exists several times in different branches.
 185         my $bind_ok = 0;
 186         while (my $entry = $search->shift_entry) {
 187             my $user_ldap_bind_ret = $db->bind($entry->dn, password => $password);
 188             unless ($user_ldap_bind_ret->code) {
 189                 $userldapentry = $entry;
 190                 $bind_ok = 1;
 191                 last;
 192             }
 193         }
 194
 195         unless ($bind_ok) {
 196             warn "LDAP Auth rejected : invalid password for user '$userid'.";
 197             return -1;
 198         }
 199
 200
 201     }
 202
 203     # To get here, LDAP has accepted our user's login attempt.
 204     # But we still have work to do.  See perldoc below for detailed breakdown.
 205
 206     my (%borrower);
 207         my ($borrowernumber,$cardnumber,$local_userid,$savedpw) = exists_local($userid);
 208
 209     if (( $borrowernumber and $config{update}   ) or
 210         (!$borrowernumber and $config{replicate})   ) {
 211         %borrower = ldap_entry_2_hash($userldapentry,$userid);
 212         $debug and print STDERR "checkpw_ldap received \%borrower w/ " . keys(%borrower), " keys: ", join(' ', keys %borrower), "\n";
 213     }
 214
 215     if ($borrowernumber) {
 216         if ($config{update}) { # A1, B1
 217             my $c2 = &update_local($local_userid,$password,$borrowernumber,\%borrower) || '';
 218             ($cardnumber eq $c2) or warn "update_local returned cardnumber '$c2' instead of '$cardnumber'";
 219         } else { # C1, D1
 220             # maybe update just the password?
 221                 return(1, $cardnumber, $local_userid);
 222         }
 223     } elsif ($config{replicate}) { # A2, C2
 224         my @columns = Koha::Patrons->columns;
 225         my $patron = Koha::Patron->new(
 226             {
 227                 map { exists( $borrower{$_} ) ? ( $_ => $borrower{$_} ) : () } @columns
 228             }
 229         )->store;
 230         die "Insert of new patron failed" unless $patron;
 231         $borrowernumber = $patron->borrowernumber;
 232         C4::Members::Messaging::SetMessagingPreferencesFromDefaults( { borrowernumber => $borrowernumber, categorycode => $borrower{'categorycode'} } );
 233    } else {
 234         return 0;   # B2, D2
 235     }
 236     if (C4::Context->preference('ExtendedPatronAttributes') && $borrowernumber && ($config{update} ||$config{replicate})) {
 237         foreach my $attribute_type ( C4::Members::AttributeTypes::GetAttributeTypes() ) {
 238             my $code = $attribute_type->{code};
 239             unless (exists($borrower{$code}) && $borrower{$code} !~ m/^\s*$/ ) {
 240                 next;
 241             }
 242             if (C4::Members::Attributes::CheckUniqueness($code, $borrower{$code}, $borrowernumber)) {
 243                 C4::Members::Attributes::UpdateBorrowerAttribute($borrowernumber, {code => $code, attribute => $borrower{$code}});
 244             } else {
 245                 warn "ERROR_extended_unique_id_failed $code $borrower{$code}";
 246             }
 247         }
 248     }
 249     return(1, $cardnumber, $userid);
 250 }
 251
 252 # Pass LDAP entry object and local cardnumber (userid).
 253 # Returns borrower hash.
 254 # Edit KOHA_CONF so $memberhash{'xxx'} fits your ldap structure.
 255 # Ensure that mandatory fields are correctly filled!
 256 #
 257 sub ldap_entry_2_hash {
 258         my $userldapentry = shift;
 259         my %borrower = ( cardnumber => shift );
 260         my %memberhash;
 261         $userldapentry->exists('uid');  # This is bad, but required!  By side-effect, this initializes the attrs hash.
 262         if ($debug) {
 263                 foreach (keys %$userldapentry) {
 264                         print STDERR "\n\nLDAP key: $_\t", sprintf('(%s)', ref $userldapentry->{$_}), "\n";
 265                 }
 266         }
 267         my $x = $userldapentry->{attrs} or return;
 268         foreach (keys %$x) {
 269                 $memberhash{$_} = join ' ', @{$x->{$_}};
 270                 $debug and print STDERR sprintf("building \$memberhash{%s} = ", $_, join(' ', @{$x->{$_}})), "\n";
 271         }
 272         $debug and print STDERR "Finsihed \%memberhash has ", scalar(keys %memberhash), " keys\n",
 273                                         "Referencing \%mapping with ", scalar(keys %mapping), " keys\n";
 274         foreach my $key (keys %mapping) {
 275                 my  $data = $memberhash{ lc($mapping{$key}->{is}) }; # Net::LDAP returns all names in lowercase
 276                 $debug and printf STDERR "mapping %20s ==> %-20s (%s)\n", $key, $mapping{$key}->{is}, $data;
 277                 unless (defined $data) {
 278                         $data = $mapping{$key}->{content} || '';        # default or failsafe ''
 279                 }
 280                 $borrower{$key} = ($data ne '') ? $data : ' ' ;
 281         }
 282         $borrower{initials} = $memberhash{initials} ||
 283                 ( substr($borrower{'firstname'},0,1)
 284                 . substr($borrower{ 'surname' },0,1)
 285                 . " ");
 286
 287     # categorycode conversions
 288     if(defined $categorycode_conversions{$borrower{categorycode}}) {
 289         $borrower{categorycode} = $categorycode_conversions{$borrower{categorycode}};
 290     }
 291     elsif($default_categorycode) {
 292         $borrower{categorycode} = $default_categorycode;
 293     }
 294
 295         # check if categorycode exists, if not, fallback to default from koha-conf.xml
 296         my $dbh = C4::Context->dbh;
 297         my $sth = $dbh->prepare("SELECT categorycode FROM categories WHERE categorycode = ?");
 298         $sth->execute( uc($borrower{'categorycode'}) );
 299         unless ( my $row = $sth->fetchrow_hashref ) {
 300                 my $default = $mapping{'categorycode'}->{content};
 301                 $debug && warn "Can't find ", $borrower{'categorycode'}, " default to: $default for ", $borrower{userid};
 302                 $borrower{'categorycode'} = $default
 303         }
 304
 305         return %borrower;
 306 }
 307
 308 sub exists_local {
 309         my $arg = shift;
 310         my $dbh = C4::Context->dbh;
 311         my $select = "SELECT borrowernumber,cardnumber,userid,password FROM borrowers ";
 312
 313         my $sth = $dbh->prepare("$select WHERE userid=?");      # was cardnumber=?
 314         $sth->execute($arg);
 315         $debug and printf STDERR "Userid '$arg' exists_local? %s\n", $sth->rows;
 316         ($sth->rows == 1) and return $sth->fetchrow;
 317
 318         $sth = $dbh->prepare("$select WHERE cardnumber=?");
 319         $sth->execute($arg);
 320         $debug and printf STDERR "Cardnumber '$arg' exists_local? %s\n", $sth->rows;
 321         ($sth->rows == 1) and return $sth->fetchrow;
 322         return 0;
 323 }
 324
 325 # This function performs a password update, given the userid, borrowerid,
 326 # and digested password. It will verify that things are correct and return the
 327 # borrowers cardnumber. The idea is that it is used to keep the local
 328 # passwords in sync with the LDAP passwords.
 329 #
 330 #   $cardnum = _do_changepassword($userid, $borrowerid, $digest)
 331 #
 332 # Note: if the LDAP config has the update_password tag set to a false value,
 333 # then this will not update the password, it will simply return the cardnumber.
 334 sub _do_changepassword {
 335     my ($userid, $borrowerid, $password) = @_;
 336
 337     if ( exists( $ldap->{update_password} ) && !$ldap->{update_password} ) {
 338
 339         # We don't store the password in the database
 340         my $sth = C4::Context->dbh->prepare(
 341             'SELECT cardnumber FROM borrowers WHERE borrowernumber=?');
 342         $sth->execute($borrowerid);
 343         die "Unable to access borrowernumber "
 344             . "with userid=$userid, "
 345             . "borrowernumber=$borrowerid"
 346           if !$sth->rows;
 347         my ($cardnum) = $sth->fetchrow;
 348         $sth = C4::Context->dbh->prepare(
 349             'UPDATE borrowers SET password = null WHERE borrowernumber=?');
 350         $sth->execute($borrowerid);
 351         return $cardnum;
 352     }
 353
 354     my $digest = hash_password($password);
 355     $debug and print STDERR "changing local password for borrowernumber=$borrowerid to '$digest'\n";
 356     Koha::Patrons->find($borrowerid)->set_password({ password => $password, skip_validation => 1 });
 357
 358     my ($ok, $cardnum) = checkpw_internal(C4::Context->dbh, $userid, $password);
 359     return $cardnum if $ok;
 360
 361     warn "Password mismatch after update to borrowernumber=$borrowerid";
 362     return;
 363 }
 364
 365 sub update_local {
 366     my $userid     = shift or croak "No userid";
 367     my $password   = shift or croak "No password";
 368     my $borrowerid = shift or croak "No borrowerid";
 369     my $borrower   = shift or croak "No borrower record";
 370
 371     # skip extended patron attributes in 'borrowers' attribute update
 372     my @keys = keys %$borrower;
 373     if (C4::Context->preference('ExtendedPatronAttributes')) {
 374         foreach my $attribute_type ( C4::Members::AttributeTypes::GetAttributeTypes() ) {
 375            my $code = $attribute_type->{code};
 376            @keys = grep { $_ ne $code } @keys;
 377            $debug and printf STDERR "ignoring extended patron attribute '%s' in update_local()\n", $code;
 378         }
 379     }
 380
 381     my $dbh = C4::Context->dbh;
 382     my $query = "UPDATE  borrowers\nSET     " .
 383         join(',', map {"$_=?"} @keys) .
 384         "\nWHERE   borrowernumber=? ";
 385     my $sth = $dbh->prepare($query);
 386     if ($debug) {
 387         print STDERR $query, "\n",
 388             join "\n", map {"$_ = '" . $borrower->{$_} . "'"} @keys;
 389         print STDERR "\nuserid = $userid\n";
 390     }
 391     $sth->execute(
 392         ((map {$borrower->{$_}} @keys), $borrowerid)
 393     );
 394
 395     # MODIFY PASSWORD/LOGIN if password was mapped
 396     _do_changepassword($userid, $borrowerid, $password) if $borrower->{'password'};
 397 }
 398
 399 1;
 400 __END__
 401
 402 =head1 NAME
 403
 404 C4::Auth - Authenticates Koha users
 405
 406 =head1 SYNOPSIS
 407
 408   use C4::Auth_with_ldap;
 409
 410 =head1 LDAP Configuration
 411
 412     This module is specific to LDAP authentification. It requires Net::LDAP package and one or more
 413         working LDAP servers.
 414         To use it :
 415            * Modify ldapserver element in KOHA_CONF
 416            * Establish field mapping in <mapping> element.
 417
 418         For example, if your user records are stored according to the inetOrgPerson schema, RFC#2798,
 419         the username would match the "uid" field, and the password should match the "userpassword" field.
 420
 421         Make sure that ALL required fields are populated by your LDAP database (and mapped in KOHA_CONF).
 422         What are the required fields?  Well, in mysql you can check the database table "borrowers" like this:
 423
 424         mysql> show COLUMNS from borrowers;
 425                 +---------------------+--------------+------+-----+---------+----------------+
 426                 | Field               | Type         | Null | Key | Default | Extra          |
 427                 +---------------------+--------------+------+-----+---------+----------------+
 428                 | borrowernumber      | int(11)      | NO   | PRI | NULL    | auto_increment |
 429                 | cardnumber          | varchar(16)  | YES  | UNI | NULL    |                |
 430                 | surname             | mediumtext   | NO   |     | NULL    |                |
 431                 | firstname           | text         | YES  |     | NULL    |                |
 432                 | title               | mediumtext   | YES  |     | NULL    |                |
 433                 | othernames          | mediumtext   | YES  |     | NULL    |                |
 434                 | initials            | text         | YES  |     | NULL    |                |
 435                 | streetnumber        | varchar(10)  | YES  |     | NULL    |                |
 436                 | streettype          | varchar(50)  | YES  |     | NULL    |                |
 437                 | address             | mediumtext   | NO   |     | NULL    |                |
 438                 | address2            | text         | YES  |     | NULL    |                |
 439                 | city                | mediumtext   | NO   |     | NULL    |                |
 440                 | state               | mediumtext   | YES  |     | NULL    |                |
 441                 | zipcode             | varchar(25)  | YES  |     | NULL    |                |
 442                 | country             | text         | YES  |     | NULL    |                |
 443                 | email               | mediumtext   | YES  |     | NULL    |                |
 444                 | phone               | text         | YES  |     | NULL    |                |
 445                 | mobile              | varchar(50)  | YES  |     | NULL    |                |
 446                 | fax                 | mediumtext   | YES  |     | NULL    |                |
 447                 | emailpro            | text         | YES  |     | NULL    |                |
 448                 | phonepro            | text         | YES  |     | NULL    |                |
 449                 | B_streetnumber      | varchar(10)  | YES  |     | NULL    |                |
 450                 | B_streettype        | varchar(50)  | YES  |     | NULL    |                |
 451                 | B_address           | varchar(100) | YES  |     | NULL    |                |
 452                 | B_address2          | text         | YES  |     | NULL    |                |
 453                 | B_city              | mediumtext   | YES  |     | NULL    |                |
 454                 | B_state             | mediumtext   | YES  |     | NULL    |                |
 455                 | B_zipcode           | varchar(25)  | YES  |     | NULL    |                |
 456                 | B_country           | text         | YES  |     | NULL    |                |
 457                 | B_email             | text         | YES  |     | NULL    |                |
 458                 | B_phone             | mediumtext   | YES  |     | NULL    |                |
 459                 | dateofbirth         | date         | YES  |     | NULL    |                |
 460                 | branchcode          | varchar(10)  | NO   | MUL |         |                |
 461                 | categorycode        | varchar(10)  | NO   | MUL |         |                |
 462                 | dateenrolled        | date         | YES  |     | NULL    |                |
 463                 | dateexpiry          | date         | YES  |     | NULL    |                |
 464                 | gonenoaddress       | tinyint(1)   | YES  |     | NULL    |                |
 465                 | lost                | tinyint(1)   | YES  |     | NULL    |                |
 466                 | debarred            | date         | YES  |     | NULL    |                |
 467                 | debarredcomment     | varchar(255) | YES  |     | NULL    |                |
 468                 | contactname         | mediumtext   | YES  |     | NULL    |                |
 469                 | contactfirstname    | text         | YES  |     | NULL    |                |
 470                 | contacttitle        | text         | YES  |     | NULL    |                |
 471                 | borrowernotes       | mediumtext   | YES  |     | NULL    |                |
 472                 | relationship        | varchar(100) | YES  |     | NULL    |                |
 473                 | ethnicity           | varchar(50)  | YES  |     | NULL    |                |
 474                 | ethnotes            | varchar(255) | YES  |     | NULL    |                |
 475                 | sex                 | varchar(1)   | YES  |     | NULL    |                |
 476                 | password            | varchar(30)  | YES  |     | NULL    |                |
 477                 | flags               | int(11)      | YES  |     | NULL    |                |
 478                 | userid              | varchar(30)  | YES  | MUL | NULL    |                |
 479                 | opacnote            | mediumtext   | YES  |     | NULL    |                |
 480                 | contactnote         | varchar(255) | YES  |     | NULL    |                |
 481                 | sort1               | varchar(80)  | YES  |     | NULL    |                |
 482                 | sort2               | varchar(80)  | YES  |     | NULL    |                |
 483                 | altcontactfirstname | varchar(255) | YES  |     | NULL    |                |
 484                 | altcontactsurname   | varchar(255) | YES  |     | NULL    |                |
 485                 | altcontactaddress1  | varchar(255) | YES  |     | NULL    |                |
 486                 | altcontactaddress2  | varchar(255) | YES  |     | NULL    |                |
 487                 | altcontactaddress3  | varchar(255) | YES  |     | NULL    |                |
 488                 | altcontactstate     | mediumtext   | YES  |     | NULL    |                |
 489                 | altcontactzipcode   | varchar(50)  | YES  |     | NULL    |                |
 490                 | altcontactcountry   | text         | YES  |     | NULL    |                |
 491                 | altcontactphone     | varchar(50)  | YES  |     | NULL    |                |
 492                 | smsalertnumber      | varchar(50)  | YES  |     | NULL    |                |
 493                 | privacy             | int(11)      | NO   |     | 1       |                |
 494                 +---------------------+--------------+------+-----+---------+----------------+
 495                 66 rows in set (0.00 sec)
 496                 Where Null="NO", the field is required.
 497
 498 =head1 KOHA_CONF and field mapping
 499
 500 Example XML stanza for LDAP configuration in KOHA_CONF.
 501
 502  <config>
 503   ...
 504   <useldapserver>1</useldapserver>
 505   <!-- LDAP SERVER (optional) -->
 506   <ldapserver id="ldapserver">
 507     <hostname>localhost</hostname>
 508     <base>dc=metavore,dc=com</base>
 509     <user>cn=Manager,dc=metavore,dc=com</user>             <!-- DN, if not anonymous -->
 510     <pass>metavore</pass>          <!-- password, if not anonymous -->
 511     <replicate>1</replicate>       <!-- add new users from LDAP to Koha database -->
 512     <update>1</update>             <!-- update existing users in Koha database -->
 513     <auth_by_bind>0</auth_by_bind> <!-- set to 1 to authenticate by binding instead of
 514                                         password comparison, e.g., to use Active Directory -->
 515     <anonymous_bind>0</anonymous_bind> <!-- set to 1 if users should be searched using
 516                                             an anonymous bind, even when auth_by_bind is on -->
 517     <principal_name>%s@my_domain.com</principal_name>
 518                                    <!-- optional, for auth_by_bind: a printf format to make userPrincipalName from koha userid.
 519                                         Not used with anonymous_bind. -->
 520     <update_password>1</update_password> <!-- set to 0 if you don't want LDAP passwords
 521                                               synced to the local database -->
 522     <mapping>                  <!-- match koha SQL field names to your LDAP record field names -->
 523       <firstname    is="givenname"      ></firstname>
 524       <surname      is="sn"             ></surname>
 525       <address      is="postaladdress"  ></address>
 526       <city         is="l"              >Athens, OH</city>
 527       <zipcode      is="postalcode"     ></zipcode>
 528       <branchcode   is="branch"         >MAIN</branchcode>
 529       <userid       is="uid"            ></userid>
 530       <password     is="userpassword"   ></password>
 531       <email        is="mail"           ></email>
 532       <categorycode is="employeetype"   >PT</categorycode>
 533       <phone        is="telephonenumber"></phone>
 534     </mapping>
 535   </ldapserver>
 536  </config>
 537
 538 The <mapping> subelements establish the relationship between mysql fields and LDAP attributes. The element name
 539 is the column in mysql, with the "is" characteristic set to the LDAP attribute name.  Optionally, any content
 540 between the element tags is taken as the default value.  In this example, the default categorycode is "PT" (for
 541 patron).
 542
 543 =head1 CONFIGURATION
 544
 545 Once a user has been accepted by the LDAP server, there are several possibilities for how Koha will behave, depending on
 546 your configuration and the presence of a matching Koha user in your local DB:
 547
 548                          LOCAL_USER
 549  OPTION UPDATE REPLICATE  EXISTS?  RESULT
 550    A1      1       1        1      OK : We're updating them anyway.
 551    A2      1       1        0      OK : We're adding them anyway.
 552    B1      1       0        1      OK : We update them.
 553    B2      1       0        0     FAIL: We cannot add new user.
 554    C1      0       1        1      OK : We do nothing.  (maybe should update password?)
 555    C2      0       1        0      OK : We add the new user.
 556    D1      0       0        1      OK : We do nothing.  (maybe should update password?)
 557    D2      0       0        0     FAIL: We cannot add new user.
 558
 559 Note: failure here just means that Koha will fallback to checking the local DB.  That is, a given user could login with
 560 their LDAP password OR their local one.  If this is a problem, then you should enable update and supply a mapping for
 561 password.  Then the local value will be updated at successful LDAP login and the passwords will be synced.
 562
 563 If you choose NOT to update local users, the borrowers table will not be affected at all.
 564 Note that this means that patron passwords may appear to change if LDAP is ever disabled, because
 565 the local table never contained the LDAP values.
 566
 567 =head2 auth_by_bind
 568
 569 Binds as the user instead of retrieving their record.  Recommended if update disabled.
 570
 571 =head2 principal_name
 572
 573 Provides an optional sprintf-style format for manipulating the userid before the bind.
 574 Even though the userPrincipalName is one intended target, any uniquely identifying
 575 attribute that the server allows to be used for binding could be used.
 576
 577 Currently, principal_name only operates when auth_by_bind is enabled.
 578
 579 =head2 update_password
 580
 581 If this tag is left out or set to a true value, then the user's LDAP password
 582 will be stored (hashed) in the local Koha database. If you don't want this
 583 to happen, then set the value of this to '0'. Note that if passwords are not
 584 stored locally, and the connection to the LDAP system fails, then the users
 585 will not be able to log in at all.
 586
 587 =head2 Active Directory
 588
 589 The auth_by_bind and principal_name settings are recommended for Active Directory.
 590
 591 Under default Active Directory rules, we cannot determine the distinguishedName attribute from the Koha userid as reliably as
 592 we would typically under openldap.  Instead of:
 593
 594     distinguishedName: CN=barnes.7,DC=my_company,DC=com
 595
 596 We might get:
 597
 598     distinguishedName: CN=Barnes\, Jim,OU=Test Accounts,OU=User Accounts,DC=my_company,DC=com
 599
 600 Matching that would require us to know more info about the account (firstname, surname) and to include punctuation and whitespace
 601 in Koha userids.  But the userPrincipalName should be consistent, something like:
 602
 603     userPrincipalName: barnes.7@my_company.com
 604
 605 Therefore it is often easier to bind to Active Directory with userPrincipalName, effectively the
 606 canonical email address for that user, or what it would be if email were enabled for them.  If Koha userid values
 607 will match the username portion of the userPrincipalName, and the domain suffix is the same for all users, then use principal_name
 608 like this:
 609     <principal_name>%s@core.my_company.com</principal_name>
 610
 611 The user of the previous example, barnes.7, would then attempt to bind as:
 612     barnes.7@core.my_company.com
 613
 614 =head1 SEE ALSO
 615
 616 CGI(3)
 617
 618 Net::LDAP()
 619
 620 XML::Simple()
 621
 622 Digest::MD5(3)
 623
 624 sprintf()
 625
 626 =cut
 627
 628 # For reference, here's an important difference in the data structure we rely on.
 629 # ========================================
 630 # Using attrs instead of {asn}->attributes
 631 # ========================================
 632 #
 633 #       LDAP key: ->{             cn} = ARRAY w/ 3 members.
 634 #       LDAP key: ->{             cn}->{           sss} = sss
 635 #       LDAP key: ->{             cn}->{   Steve Smith} = Steve Smith
 636 #       LDAP key: ->{             cn}->{Steve S. Smith} = Steve S. Smith
 637 #
 638 #       LDAP key: ->{      givenname} = ARRAY w/ 1 members.
 639 #       LDAP key: ->{      givenname}->{Steve} = Steve
 640 #