# ipdb/cgi-bin/IPDB.pm
# Contains functions for IPDB - database access, subnet mangling, block allocation, etc
###
# SVN revision info
# $Date: 2013-05-14 21:45:17 +0000 (Tue, 14 May 2013) $
# SVN revision $Rev: 592 $
# Last update by $Author: kdeugau $
###
# Copyright (C) 2004-2010 - Kris Deugau

package IPDB;

use strict;
use warnings;
use Exporter;
use DBI;
use Net::SMTP;
use NetAddr::IP qw( Compact );
use POSIX;
use vars qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS);

$VERSION	= 2; ##VERSION##
@ISA		= qw(Exporter);
@EXPORT_OK    = qw(
	%disp_alloctypes %list_alloctypes %def_custids @citylist @poplist @masterblocks
	%allocated %free %routed %bigfree %IPDBacl
	&initIPDBGlobals &connectDB &finish &checkDBSanity &allocateBlock &addMaster
	&deleteBlock &getBlockData &mailNotify
	);

@EXPORT		= (); # Export nothing by default.
%EXPORT_TAGS	= ( ALL => [qw(
		%disp_alloctypes %list_alloctypes %def_custids @citylist @poplist
		@masterblocks %allocated %free %routed %bigfree %IPDBacl
		&initIPDBGlobals &connectDB &finish &checkDBSanity &allocateBlock
		&addMaster &deleteBlock &getBlockData &mailNotify
		)]
	);

##
## Global variables
##
our %disp_alloctypes;
our %list_alloctypes;
our %def_custids;
our @citylist;
our @poplist;
our @masterblocks;
our %allocated;
our %free;
our %routed;
our %bigfree;
our %IPDBacl;

our $org_name = 'Example Corp';
our $smtphost = 'smtp.example.com';
our $domain = 'example.com';
our $defcustid = '5554242';
# mostly for rwhois
##fixme:  leave these blank by default?
our $rwhoisDataPath = '/usr/local/rwhoisd/etc/rwhoisd';	# to match ./configure defaults from rwhoisd-1.5.9.6
our $org_street = '123 4th Street';
our $org_city = 'Anytown';
our $org_prov_state = 'ON';
our $org_pocode = 'H0H 0H0';
our $org_country = 'CA';
our $org_phone = '000-555-1234';
our $org_techhandle = 'ISP-ARIN-HANDLE';
our $org_email = 'noc@example.com';
our $hostmaster = 'dns@example.com';

our $syslog_facility = 'local2';

# Allow allocations to come from private IP ranges by default?
# Set to 'y' or 'on' to enable.
our $allowprivrange = '';

# Let's initialize the globals.
## IPDB::initIPDBGlobals()
# Initialize all globals.  Takes a database handle, returns a success or error code
sub initIPDBGlobals {
  my $dbh = $_[0];
  my $sth;

  # Initialize alloctypes hashes
  $sth = $dbh->prepare("select type,listname,dispname,listorder,def_custid from alloctypes order by listorder");
  $sth->execute;
  while (my @data = $sth->fetchrow_array) {
    $disp_alloctypes{$data[0]} = $data[2];
    $def_custids{$data[0]} = $data[4];
    if ($data[3] < 900) {
      $list_alloctypes{$data[0]} = $data[1];
    }
  }

  # City and POP listings
  $sth = $dbh->prepare("select city,routing from cities order by city");
  $sth->execute;
  return (undef,$sth->errstr) if $sth->err;
  while (my @data = $sth->fetchrow_array) {
    push @citylist, $data[0];
    if ($data[1] eq 'y') {
      push @poplist, $data[0];
    }
  }

  # Master block list
  $sth = $dbh->prepare("select cidr from masterblocks order by cidr");
  $sth->execute;
  return (undef,$sth->errstr) if $sth->err;
  for (my $i=0; my @data = $sth->fetchrow_array(); $i++) {
    $masterblocks[$i] = new NetAddr::IP $data[0];
    $allocated{"$masterblocks[$i]"} = 0;
    $free{"$masterblocks[$i]"} = 0;
    $bigfree{"$masterblocks[$i]"} = 128; # Larger number means smaller block.
					# Set to 128 to prepare for IPv6
    $routed{"$masterblocks[$i]"} = 0;
  }

  # Load ACL data.  Specific username checks are done at a different level.
  $sth = $dbh->prepare("select username,acl from users");
  $sth->execute;
  return (undef,$sth->errstr) if $sth->err;
  while (my @data = $sth->fetchrow_array) {
    $IPDBacl{$data[0]} = $data[1];
  }

  return (1,"OK");
} # end initIPDBGlobals


## IPDB::connectDB()
# Creates connection to IPDB.
# Requires the database name, username, and password.
# Returns a handle to the db.
# Set up for a PostgreSQL db;  could be any transactional DBMS with the
# right changes.
sub connectDB {
  my $dbname = shift;
  my $user = shift;
  my $pass = shift;
  my $dbhost = shift;

  my $dbh;
  my $DSN = "DBI:Pg:".($dbhost ? "host=$dbhost;" : '')."dbname=$dbname";

# Note that we want to autocommit by default, and we will turn it off locally as necessary.
# We may not want to print gobbledygook errors;  YMMV.  Have to ponder that further.
  $dbh = DBI->connect($DSN, $user, $pass, {
	AutoCommit => 1,
	PrintError => 0
	})
    or return (undef, $DBI::errstr) if(!$dbh);

# Return here if we can't select.  Note that this indicates a
# problem executing the select.
  my $sth = $dbh->prepare("select type from alloctypes");
  $sth->execute();
  return (undef,$DBI::errstr) if ($sth->err);

# See if the select returned anything (or null data).  This should
# succeed if the select executed, but...
  $sth->fetchrow();
  return (undef,$DBI::errstr)  if ($sth->err);

# If we get here, we should be OK.
  return ($dbh,"DB connection OK");
} # end connectDB


## IPDB::finish()
# Cleans up after database handles and so on.
# Requires a database handle
sub finish {
  my $dbh = $_[0];
  $dbh->disconnect;
} # end finish


## IPDB::checkDBSanity()
# Quick check to see if the db is responding.  A full integrity
# check will have to be a separate tool to walk the IP allocation trees.
sub checkDBSanity {
  my ($dbh) = $_[0];

  if (!$dbh) {
    print "No database handle, or connection has been closed.";
    return -1;
  } else {
    # it connects, try a stmt.
    my $sth = $dbh->prepare("select type from alloctypes");
    my $err = $sth->execute();

    if ($sth->fetchrow()) {
      # all is well.
      return 1;
    } else {
      print "Connected to the database, but could not execute test statement.  ".$sth->errstr();
      return -1;
    }
  }
  # Clean up after ourselves.
#  $dbh->disconnect;
} # end checkDBSanity


## IPDB::addMaster()
# Does all the magic necessary to sucessfully add a master block
# Requires database handle, block to add
# Returns failure code and error message or success code and "message"
sub addMaster {
  my $dbh = shift;
  my $cidr = new NetAddr::IP shift;

  # Allow transactions, and raise an exception on errors so we can catch it later.
  # Use local to make sure these get "reset" properly on exiting this block
  local $dbh->{AutoCommit} = 0;
  local $dbh->{RaiseError} = 1;

  # Wrap all the SQL in a transaction
  eval {
    my $sth = $dbh->prepare("select count(*) from masterblocks where cidr <<= '$cidr'");
    $sth->execute;
    my @data = $sth->fetchrow_array;

    if ($data[0] eq 0) {
      # First case - master is brand-spanking-new.
##fixme: rwhois should be globally-flagable somewhere, much like a number of other things
## maybe a db table called "config"?
      $sth = $dbh->prepare("insert into masterblocks (cidr,rwhois) values ('$cidr','y')");
      $sth->execute;

# Unrouted blocks aren't associated with a city (yet).  We don't rely on this
# elsewhere though;  legacy data may have traps and pitfalls in it to break this.
# Thus the "routed" flag.

      $sth = $dbh->prepare("insert into freeblocks (cidr,maskbits,city,routed)".
        " values ('$cidr',".$cidr->masklen.",'<NULL>','n')");
      $sth->execute;

      # If we get here, everything is happy.  Commit changes.
      $dbh->commit;

    } # new master does not contain existing master(s)
    else {

      # collect the master(s) we're going to absorb, and snag the longest netmask while we're at it.
      my $smallmask = $cidr->masklen;
      $sth = $dbh->prepare("select cidr as mask from masterblocks where cidr <<= '$cidr'");
      $sth->execute;
      my @cmasters;
      while (my @data = $sth->fetchrow_array) {
	my $master = new NetAddr::IP $data[0];
	push @cmasters, $master;
	$smallmask = $master->masklen if $master->masklen > $smallmask;
      }

      # split the new master, and keep only those blocks not part of an existing master
      my @blocklist;
      foreach my $seg ($cidr->split($smallmask)) {
	my $contained = 0;
	foreach my $master (@cmasters) {
	  $contained = 1 if $master->contains($seg);
	}
	push @blocklist, $seg if !$contained;
      }

      # collect the unrouted free blocks within the new master
      $sth = $dbh->prepare("select cidr from freeblocks where ".
		"maskbits>=$smallmask and cidr <<= '$cidr' and routed='n'");
      $sth->execute;
      while (my @data = $sth->fetchrow_array) {
	my $freeblock = new NetAddr::IP $data[0];
	push @blocklist, $freeblock;
      }

      # combine the set of free blocks we should have now.
      @blocklist = Compact(@blocklist);

      # and now insert the new data.  Make sure to delete old masters too.

      # freeblocks
      $sth = $dbh->prepare("delete from freeblocks where cidr <<= ?");
      my $sth2 = $dbh->prepare("insert into freeblocks (cidr,maskbits,city,routed) values (?,?,'<NULL>','n')");
      foreach my $newblock (@blocklist) {
        $sth->execute("$newblock");
        $sth2->execute("$newblock", $newblock->masklen);
      }

      # master
      $sth = $dbh->prepare("delete from masterblocks where cidr <<= '$cidr'");
      $sth->execute;
      $sth = $dbh->prepare("insert into masterblocks (cidr,rwhois) values ('$cidr','y')");
      $sth->execute;

      # *whew*  If we got here, we likely suceeded.
      $dbh->commit;
    } # new master contained existing master(s)
  }; # end eval

  if ($@) {
    my $msg = $@;
    eval { $dbh->rollback; };
    return ('FAIL',$msg);
  } else {
    return ('OK','OK');
  }
} # end addMaster


## IPDB::allocateBlock()
# Does all of the magic of actually allocating a netblock
# Requires database handle, block to allocate, custid, type, city,
#	description, notes, circuit ID, block to allocate from, private data
# Returns a success code and optional error message.
sub allocateBlock {
  my ($dbh,undef,undef,$custid,$type,$city,$desc,$notes,$circid,$privdata,$nodeid) = @_;
  $privdata = '' if !defined($privdata);

  my $cidr = new NetAddr::IP $_[1];
  my $alloc_from = new NetAddr::IP $_[2];
  my $sth;

  $desc = '' if !$desc;
  $notes = '' if !$notes;
  $circid = '' if !$circid;
  $privdata = '' if !$privdata;

  # Snag the "type" of the freeblock (alloc_from) "just in case"
  $sth = $dbh->prepare("select routed from freeblocks where cidr='$alloc_from'");
  $sth->execute;
  my ($alloc_from_type) = $sth->fetchrow_array;

  # To contain the error message, if any.
  my $msg = "Unknown error allocating $cidr as '$type'";

  # Enable transactions and error handling
  local $dbh->{AutoCommit} = 0;	# These need to be local so we don't
  local $dbh->{RaiseError} = 1;	# step on our toes by accident.

  if ($type =~ /^.i$/) {
    $msg = "Unable to assign static IP $cidr to $custid";
    eval {
      # We have to do this in two parts because otherwise we lose
      # the ability to return the IP assigned.  Should that change,
      # the commented SQL statement below may become usable.
# update poolips set custid='$custid',city='$city',available='n',
#	description='$desc',notes='$notes',circuitid='$circid'
#	where ip=(select ip from poolips where pool='$alloc_from'
#	and available='y' order by ip limit 1);

# If no specific IP was requested, pick the next available one from the pool.
      if (!$cidr) {
        $sth = $dbh->prepare("select ip from poolips where pool='$alloc_from'".
	  " and available='y' order by ip");
        $sth->execute;

        my @data = $sth->fetchrow_array;
        $cidr = $data[0];  # $cidr is already declared when we get here!
      }

      $sth = $dbh->prepare("update poolips set custid='$custid',".
	"city='$city',available='n',description='$desc',notes='$notes',".
	"circuitid='$circid',privdata='$privdata'".
	" where ip='$cidr'");
      $sth->execute;
# node hack
      if ($nodeid && $nodeid ne '') {
        $sth = $dbh->prepare("INSERT INTO noderef (block,node_id) VALUES (?,?)");
        $sth->execute("$cidr",$nodeid);
      }
# end node hack
      $dbh->commit;
    };
    if ($@) {
      $msg .= ": '".$sth->errstr."'";
      eval { $dbh->rollback; };
      return ('FAIL',$msg);
    } else {
      return ('OK',"$cidr");
    }

  } else { # end IP-from-pool allocation

    my $errcode = 'OK';
    if ($cidr == $alloc_from) {
      # Easiest case- insert in one table, delete in the other, and go home.  More or less.
      # insert into allocations values (cidr,custid,type,city,desc) and
      # delete from freeblocks where cidr='cidr'
      # For data safety on non-transaction DBs, we delete first.

      eval {
	$msg = "Unable to allocate $cidr as '$disp_alloctypes{$type}'";
	if ($type eq 'rm') {
	  $sth = $dbh->prepare("update freeblocks set routed='y',city='$city'".
	    " where cidr='$cidr'");
	  $sth->execute;
	  $sth = $dbh->prepare("insert into routed (cidr,maskbits,city)".
		" values ('$cidr',".$cidr->masklen.",'$city')");
	  $sth->execute;
	} else {
	  # common stuff for end-use, dialup, dynDSL, pools, etc, etc.

	  # special case - block is a container/"reserve" block
	  if ($type =~ /^(.)c$/) {
	    $sth = $dbh->prepare("update freeblocks set routed='$1' where cidr='$cidr'");
	    $sth->execute;
	  } else {
	    # "normal" case
	    $sth = $dbh->prepare("delete from freeblocks where cidr='$cidr'");
	    $sth->execute;
	  }
	  $sth = $dbh->prepare("insert into allocations".
		" (cidr,custid,type,city,description,notes,maskbits,circuitid,privdata)".
		" values ('$cidr','$custid','$type','$city',?,?,".
		$cidr->masklen.",?,?)");
	  $sth->execute($desc,$notes,$circid,$privdata);

	  # And initialize the pool, if necessary
	  # PPPoE pools (currently dialup, DSL, and WiFi) get all IPs made available
	  # "DHCP" or "real-subnet" pools have the net, gw, and bcast IPs removed.
	  if ($type =~ /^.p$/) {
	    $msg = "Could not initialize IPs in new $disp_alloctypes{$type} $cidr";
	    my ($code,$rmsg) = initPool($dbh,$cidr,$type,$city,"all");
	    die $rmsg if $code eq 'FAIL';
	    $msg = $rmsg;
	    $errcode = $code;
	  } elsif ($type =~ /^.d$/) {
	    $msg = "Could not initialize IPs in new $disp_alloctypes{$type} $cidr";
	    my ($code,$rmsg) = initPool($dbh,$cidr,$type,$city,"normal");
	    die $rmsg if $code eq 'FAIL';
	    $msg = $rmsg;
	    $errcode = $code;
	  }

	} # routing vs non-routing netblock

# node hack
      if ($nodeid && $nodeid ne '') {
        $sth = $dbh->prepare("INSERT INTO noderef (block,node_id) VALUES (?,?)");
        $sth->execute("$cidr",$nodeid);
      }
# end node hack
	$dbh->commit;
      }; # end of eval
      if ($@) {
	$msg .= ": ".$@;
	eval { $dbh->rollback; };
	return ('FAIL',$msg);
      } else {
	return ($errcode,($type =~ /^.[pd]$/ ? $msg : "OK"));
      }

    } else { # cidr != alloc_from

      # Hard case.  Allocation is smaller than free block.
      my $wantmaskbits = $cidr->masklen;
      my $maskbits = $alloc_from->masklen;

      my @newfreeblocks;	# Holds free blocks generated from splitting the source freeblock.

      # This determines which blocks will be left "free" after allocation.  We take the
      # block we're allocating from, and split it in half.  We see which half the wanted
      # block is in, and repeat until the wanted block is equal to one of the halves.
      my $i=0;
      my $tmp_from = $alloc_from;	# So we don't munge $alloc_from
      while ($maskbits++ < $wantmaskbits) {
	my @subblocks = $tmp_from->split($maskbits);
	$newfreeblocks[$i++] = (($cidr->within($subblocks[0])) ? $subblocks[1] : $subblocks[0]);
	$tmp_from = ( ($cidr->within($subblocks[0])) ? $subblocks[0] : $subblocks[1] );
      } # while

      # Begin SQL transaction block
      eval {
	$msg = "Unable to allocate $cidr as '$disp_alloctypes{$type}'";

	# Delete old freeblocks entry
	$sth = $dbh->prepare("delete from freeblocks where cidr='$alloc_from'");
	$sth->execute();

	# now we have to do some magic for routing blocks
	if ($type eq 'rm') {

	  # Insert the new freeblocks entries
	  # Note that non-routed blocks are assigned to <NULL>
	  # and use the default value for the routed column ('n')
	  $sth = $dbh->prepare("insert into freeblocks (cidr,maskbits,city)".
		" values (?, ?, '<NULL>')");
	  foreach my $block (@newfreeblocks) {
 	    $sth->execute("$block", $block->masklen);
	  }

	  # Insert the entry in the routed table
	  $sth = $dbh->prepare("insert into routed (cidr,maskbits,city)".
		" values ('$cidr',".$cidr->masklen.",'$city')");
	  $sth->execute;
	  # Insert the (almost) same entry in the freeblocks table
	  $sth = $dbh->prepare("insert into freeblocks (cidr,maskbits,city,routed)".
		" values ('$cidr',".$cidr->masklen.",'$city','y')");
	  $sth->execute;

	} else { # done with alloctype == rm

	  # Insert the new freeblocks entries
	  # Along with some more HairyPerl(TM):
	  #   if $alloc_type_from is p
	  #   OR
	  #   $type matches /^(.)r$/
	  # inserted value for routed column should match.
	  # This solves the case of inserting an arbitrary block into a
	  # "Reserve-for-routed-DSL" block.  Which you really shouldn't
	  # do in the first place, but anyway...
	  $sth = $dbh->prepare("insert into freeblocks (cidr,maskbits,city,routed)".
		" values (?, ?, (select city from routed where cidr >>= '$cidr'),'".
		( ( ($alloc_from_type =~ /^(p)$/) || ($type =~ /^(.)r$/) ) ? "$1" : 'y')."')");
	  foreach my $block (@newfreeblocks) {
 	    $sth->execute("$block", $block->masklen);
	  }
	  # Special-case for reserve/"container" blocks - generate
	  # the "extra" freeblocks entry for the container
	  if ($type =~ /^(.)c$/) {
	    $sth = $dbh->prepare("insert into freeblocks (cidr,maskbits,city,routed)".
		" values ('$cidr',".$cidr->masklen.",'$city','$1')");
	    $sth->execute;
	  }
	  # Insert the allocations entry
	  $sth = $dbh->prepare("insert into allocations (cidr,custid,type,city,".
		"description,notes,maskbits,circuitid,privdata)".
		" values ('$cidr','$custid','$type','$city',?,?,".
		$cidr->masklen.",?,?)");
	  $sth->execute($desc,$notes,$circid,$privdata);

	  # And initialize the pool, if necessary
	  # PPPoE pools (currently dialup, DSL, and WiFi) get all IPs made available
	  # "DHCP" or "real-subnet" pools have the net, gw, and bcast IPs removed.
	  if ($type =~ /^.p$/) {
	    $msg = "Could not initialize IPs in new $disp_alloctypes{$type} $cidr";
	    my ($code,$rmsg) = initPool($dbh,$cidr,$type,$city,"all");
	    die $rmsg if $code eq 'FAIL';
	  } elsif ($type =~ /^.d$/) {
	    $msg = "Could not initialize IPs in new $disp_alloctypes{$type} $cidr";
	    my ($code,$rmsg) = initPool($dbh,$cidr,$type,$city,"normal");
	    die $rmsg if $code eq 'FAIL';
	  }

	} # done with netblock alloctype != rm

# node hack
      if ($nodeid && $nodeid ne '') {
        $sth = $dbh->prepare("INSERT INTO noderef (block,node_id) VALUES (?,?)");
        $sth->execute("$cidr",$nodeid);
      }
# end node hack
        $dbh->commit;
      }; # end eval
      if ($@) {
	$msg .= ": ".$@;
	eval { $dbh->rollback; };
	return ('FAIL',$msg);
      } else {
	return ($errcode,($type =~ /^.[pd]$/ ? $msg : "OK"));
      }

    } # end fullcidr != alloc_from

  } # end static-IP vs netblock allocation

} # end allocateBlock()


## IPDB::initPool()
# Initializes a pool
# Requires a database handle, the pool CIDR, type, city, and a parameter
# indicating whether the pool should allow allocation of literally every
# IP, or if it should reserve network/gateway/broadcast IPs
# Note that this is NOT done in a transaction, that's why it's a private
# function and should ONLY EVER get called from allocateBlock()
sub initPool {
  my ($dbh,undef,$type,$city,$class) = @_;
  my $pool = new NetAddr::IP $_[1];

  return ('WARN','Refusing to melt server with IPv6 IP pool') if $pool->bits == 128;

##fixme Need to just replace 2nd char of type with i rather than capturing 1st char of type
  $type =~ s/[pd]$/i/;
  my $sth;
  my $msg;

  # Trap errors so we can pass them back to the caller.  Even if the
  # caller is only ever supposed to be local, and therefore already
  # trapping errors.  >:(
  local $dbh->{AutoCommit} = 0; # These need to be local so we don't
  local $dbh->{RaiseError} = 1; # step on our toes by accident.

  eval {
    # have to insert all pool IPs into poolips table as "unallocated".
    $sth = $dbh->prepare("insert into poolips (pool,ip,custid,city,type)".
	" values ('$pool', ?, '$defcustid', ?, '$type')");
    my @poolip_list = $pool->hostenum;
    if ($class eq 'all') { # (DSL-ish block - *all* IPs available
      if ($pool->addr !~ /\.0$/) {	# .0 causes weirdness.
	$sth->execute($pool->addr, $city);
      }
      for (my $i=0; $i<=$#poolip_list; $i++) {
	$sth->execute($poolip_list[$i]->addr, $city);
      }
      $pool--;
      if ($pool->addr !~ /\.255$/) {	# .255 can cause weirdness.
	$sth->execute($pool->addr, $city);
      }
    } else { # (real netblock)
      for (my $i=1; $i<=$#poolip_list; $i++) {
	$sth->execute($poolip_list[$i]->addr, $city);
      }
    }
  };
  if ($@) {
    $msg = $@." '".$sth->errstr."'";
    eval { $dbh->rollback; };
    return ('FAIL',$msg);
  } else {
    return ('OK',"OK");
  }
} # end initPool()


## IPDB::deleteBlock()
# Removes an allocation from the database, including deleting IPs
# from poolips and recombining entries in freeblocks if possible
# Also handles "deleting" a static IP allocation, and removal of a master
# Requires a database handle, the block to delete, and the type of block
sub deleteBlock {
  my ($dbh,undef,$type) = @_;
  my $cidr = new NetAddr::IP $_[1];

  my $sth;

  # Magic variables used for odd allocation cases.
  my $container;
  my $con_type;

  # To contain the error message, if any.
  my $msg = "Unknown error deallocating $type $cidr";
  # Enable transactions and exception-on-errors... but only for this sub
  local $dbh->{AutoCommit} = 0;
  local $dbh->{RaiseError} = 1;

  # First case.  The "block" is a static IP
  # Note that we still need some additional code in the odd case
  # of a netblock-aligned contiguous group of static IPs
  if ($type =~ /^.i$/) {

    eval {
      $msg = "Unable to deallocate $disp_alloctypes{$type} $cidr";
      $sth = $dbh->prepare("update poolips set custid='$defcustid',available='y',".
	"city=(select city from allocations where cidr >>= '$cidr'".
	" order by masklen(cidr) desc limit 1),".
	"description='',notes='',circuitid='' where ip='$cidr'");
      $sth->execute;
      $dbh->commit;
    };
    if ($@) {
      eval { $dbh->rollback; };
      return ('FAIL',$msg);
    } else {
      return ('OK',"OK");
    }

  } elsif ($type eq 'mm') { # end alloctype =~ /.i/

    $msg = "Unable to delete master block $cidr";
    eval {
      $sth = $dbh->prepare("delete from masterblocks where cidr='$cidr'");
      $sth->execute;
      $sth = $dbh->prepare("delete from freeblocks where cidr <<= '$cidr'");
      $sth->execute;
      $dbh->commit;
    };
    if ($@) {
      eval { $dbh->rollback; };
      return ('FAIL', $msg);
    } else {
      return ('OK',"OK");
    }

  } else { # end alloctype master block case

    ## This is a big block; but it HAS to be done in a chunk.  Any removal
    ## of a netblock allocation may result in a larger chunk of free
    ## contiguous IP space - which may in turn be combined into a single
    ## netblock rather than a number of smaller netblocks.

    eval {

      if ($type eq 'rm') {
        $msg = "Unable to remove routing allocation $cidr";
	$sth = $dbh->prepare("delete from routed where cidr='$cidr'");
	$sth->execute;
	# Make sure block getting deleted is properly accounted for.
	$sth = $dbh->prepare("update freeblocks set routed='n',city='<NULL>'".
		" where cidr='$cidr'");
	$sth->execute;
	# Set up query to start compacting free blocks.
	$sth = $dbh->prepare("select cidr from freeblocks where ".
		"maskbits<=".$cidr->masklen." and routed='n' order by maskbits desc");

      } else { # end alloctype routing case

	# Magic.  We need to get information about the containing block (if any)
	# so as to make sure that the freeblocks we insert get the correct "type".
	$sth = $dbh->prepare("select cidr,type from allocations where cidr >> '$cidr'");
	$sth->execute;
	($container, $con_type) = $sth->fetchrow_array;

	# Delete all allocations within the block being deleted.  This is
	# deliberate and correct, and removes the need to special-case
	# removal of "container" blocks.
	$sth = $dbh->prepare("delete from allocations where cidr <<='$cidr'");
	$sth->execute;

	# Special case - delete pool IPs
	if ($type =~ /^.[pd]$/) {
	  # We have to delete the IPs from the pool listing.
	  $sth = $dbh->prepare("delete from poolips where pool='$cidr'");
	  $sth->execute;
	}

	# Set up query for compacting free blocks.
	if ($con_type && $con_type eq 'pc') {
	  # Clean up after "bad" allocations (blocks that are not formally
	  # contained which have nevertheless been allocated from a container block)
	  # We want to make certain that the freeblocks are properly "labelled"
	  $sth = $dbh->prepare("select cidr from freeblocks where cidr <<= '$container' order by maskbits desc");
	} else {
	  # Standard deallocation.
	  $sth = $dbh->prepare("select cidr from freeblocks where cidr <<= ".
		"(select cidr from routed where cidr >>= '$cidr') ".
		" and maskbits<=".$cidr->masklen.
		" and routed='".(($type =~ /^(.)r$/) ? "$1" : 'y').
		"' order by maskbits desc");
	}

      } # end alloctype general case

      ## Deallocate legacy blocks stashed in the middle of a static IP pool
      ## This may be expandable to an even more general case of contained netblock, or other pool types.

      # Find out if the block we're deallocating is within a DSL pool
      my $sth2 = $dbh->prepare("SELECT cidr,city,type FROM allocations WHERE type LIKE '_p' AND cidr >>= ?");
      $sth2->execute("$cidr");
      my ($pool,$poolcity,$pooltype) = $sth2->fetchrow_array;

      if ($pool || $sth2->rows) {
	# We've already deleted the block, now we have to stuff its IPs into the pool.
	$pooltype =~ s/p$/i/;	# change type to static IP
	$sth2 = $dbh->prepare("INSERT INTO poolips (pool,ip,city,type,custid) values ".
		"('$pool',?,'$poolcity','$pooltype','$defcustid')");
##fixme:  need to not insert net, gateway, and bcast on "real netblock" pools (DHCPish)
	# don't insert .0
	$sth2->execute($cidr->addr) unless $cidr->addr =~ m|\.0$|;
	foreach my $ip ($cidr->hostenum) {
	  $sth2->execute("$ip");
	}
	$cidr--;
	# don't insert .255
	$sth2->execute($cidr->addr) unless $cidr->addr =~ m|\.255$|;
      } else {	# done returning IPs from a block to a static DSL pool

	# Now we look for larger-or-equal-sized free blocks in the same master (routed)
	# (super)block. If there aren't any, we can't combine blocks anyway.  If there
	# are, we check to see if we can combine blocks.
	# Execute the statement prepared in the if-else above.

	$sth->execute;

# NetAddr::IP->compact() attempts to produce the smallest inclusive block
# from the caller and the passed terms.
# EG:  if you call $cidr->compact($ip1,$ip2,$ip3) when $cidr, $ip1, $ip2,
#	and $ip3 are consecutive /27's starting on .0 (.0-.31, .32-.63,
#	.64-.95, and .96-.128), you will get an array containing a single
#	/25 as element 0 (.0-.127).  Order is not important;  you could have
#	$cidr=.32/27, $ip1=.96/27, $ip2=.0/27, and $ip3=.64/27.

	my (@together, @combinelist);
	my $i=0;
	while (my @data = $sth->fetchrow_array) {
	  my $testIP = new NetAddr::IP $data[0];
	  @together = $testIP->compact($cidr);
	  my $num = @together;
	  if ($num == 1) {
	    $cidr = $together[0];
	    $combinelist[$i++] = $testIP;
	  }
	}

	# Clear old freeblocks entries - if any.  They should all be within
	# the $cidr determined above.
	$sth = $dbh->prepare("delete from freeblocks where cidr <<='$cidr'");
	$sth->execute;

	# insert "new" freeblocks entry
	if ($type eq 'rm') {
	  $sth = $dbh->prepare("insert into freeblocks (cidr,maskbits,city)".
		" values ('$cidr',".$cidr->masklen.",'<NULL>')");
	} else {
	  # Magic hackery to insert "correct" data for deallocation of
	  # non-contained blocks allocated from within a container.
	  $type = 'pr' if $con_type && $con_type eq 'pc';

	  $sth = $dbh->prepare("insert into freeblocks (cidr,maskbits,city,routed)".
		" values ('$cidr',".$cidr->masklen.
		",(select city from routed where cidr >>= '$cidr'),'".
		(($type =~ /^(.)r$/) ? "$1" : 'y')."')");
	}
	$sth->execute;

      } # done returning IPs to the appropriate place

      # If we got here, we've succeeded.  Whew!
      $dbh->commit;
    }; # end eval
    if ($@) {
      $msg = $@;
      eval { $dbh->rollback; };
      return ('FAIL', $msg);
    } else {
      return ('OK',"OK");
    }

  } # end alloctype != netblock

} # end deleteBlock()


## IPDB::getBlockData()
# Return custid, type, city, and description for a block
sub getBlockData {
  my $dbh = shift;
  my $block = shift;

  my $sth = $dbh->prepare("select cidr,custid,type,city,description from searchme".
	" where cidr='$block'");
  $sth->execute();
  return $sth->fetchrow_array();
} # end getBlockData()


## IPDB::mailNotify()
# Sends notification mail to recipients regarding an IPDB operation
sub mailNotify {
  my $dbh = shift;
  my ($action,$subj,$message) = @_;

  return if $smtphost eq 'smtp.example.com';   # do nothing if still using default SMTP host.

##fixme: need to redesign the breakdown/processing for $action for proper handling of all cases

# split action into parts for fiddlement.  nb: there are almost certainly better ways to do this.
  my @actionbits = split //, $action;

  # want to notify anyone who has specifically requested notify on *this* type ($action as passed),
  # on "all static IP types" or "all pool types" (and other last-char-in-type groupings), on eg "all DSL types",
  # and "all events with this action"
  my @actionsets = ($action);
##fixme: ick, eww.  really gotta find a better way to handle this...
  push @actionsets, ($actionbits[0].'.'.$actionbits[2],
	$actionbits[0].$actionbits[1].'.', $actionbits[0].'a') if $action =~ /^.{3}$/;

  my $mailer = Net::SMTP->new($smtphost, Hello => "ipdb.$domain");

  # get recip list from db
  my $sth = $dbh->prepare("SELECT reciplist FROM notify WHERE action=?");

  my %reciplist;
  foreach (@actionsets) {
    $sth->execute($_);
##fixme - need to handle db errors
    my ($recipsub) = $sth->fetchrow_array;
    next if !$recipsub;
    foreach (split(/,/, $recipsub)) {
      $reciplist{$_}++;
    }
  }

  return if !%reciplist;

  foreach my $recip (keys %reciplist) {
    $mailer->mail("ipdb\@$domain");
    $mailer->to($recip);
    $mailer->data("From: \"$org_name IP Database\" <ipdb\@$domain>\n",
	"To: $recip\n",
	"Date: ".strftime("%a, %d %b %Y %H:%M:%S %z",localtime)."\n",
	"Subject: {IPDB} $subj\n",
	"X-Mailer: IPDB Notify v".sprintf("%.1d",$IPDB::VERSION)."\n",
	"Organization: $org_name\n",
	"\n$message\n");
  }
  $mailer->quit;
}

# Indicates module loaded OK.  Required by Perl.
1;