fai-chboot

#! /usr/bin/perl

#*********************************************************************
#
# fai-chboot -- manage configuration for network boot
#
# This script is part of FAI (Fully Automatic Installation)
# Copyright (C) 2003-2022 Thomas Lange, lange@cs.uni-koeln.de
# Universitaet zu Koeln
#
#*********************************************************************
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# A copy of the GNU General Public License is available as
# '/usr/share/common-licences/GPL' in the Debian GNU/Linux distribution
# or on the World Wide Web at http://www.gnu.org/copyleft/gpl.html.  You
# can also obtain it by writing to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
#*********************************************************************

# variable needed: $nfsroot

use strict;
use Socket;
use Net::hostent;
use Getopt::Std;
use File::Copy;

our ($opt_D,$opt_p,$opt_h,$opt_t,$opt_s,$opt_C,$opt_P,$opt_E,$opt_c,$opt_l,$opt_d,$opt_i,$opt_S,$opt_L,$opt_B,$opt_I,$opt_n,$opt_v,$opt_e,$opt_F,$opt_f,$opt_k,$opt_g,$opt_o,$opt_u,$opt_U,$opt_q,$opt_a);
our ($error,$pxedir,$nfsroot,$nfsroot_server,$tftproot,$verbose,$append,$action,$kernelsuffix);
our ($mac,$ipadr,$cfdir,$flags,$debug,$match,$bootprot);
our (%hname,%hexname,%type,@allfiles,@templates,@enabled,@other,@patterns,@disabled);
our ($initrd,$kernelname,$rootfs_pre,$rootfs);
$Getopt::Std::STANDARD_HELP_VERSION=1;

$0=~ s#.+/##; # remove path from program name
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub ip2hex {

  my $ipadr = shift;
  my $hex = sprintf("%02X%02X%02X%02X", split(/\./,$ipadr));
  return ($ipadr,$hex);
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub host2hex {

  my $host = shift;
  my $h;

  if ($host =~ /^\d+\.\d+\.\d+\.\d+$/) {
    # hostname is already an IP address
    return ip2hex($host);
  }
  return ('no IP','default') if ($host =~ /^default/);
  return ('no IP',"$host")   if ($host =~ /\.tmpl$/);

  # MAC address with separator "-" or ":"
  if ($host =~ /^([0-9a-fA-F]{2}([:-]|$)){6}$/i) { # pattern matching
    $host = lc $host; # lowercase for pxe-file
    my @nums = split /[:-]/, $host;
    $mac = join ('-', "01",@nums); # build pxe-filename
    return ('no IP',$mac);
  }

  if ($host =~ /^[0-9a-fA-F]{12}$/i) { # pattern matching MAC address w/o separator
    $host = lc $host;
    my @nums = split /(.{2})/, $host;
    $mac = join ('-', "01",@nums[1,3,5,7,9,11]); # build pxe-filename
    return ('no IP',$mac);
  }

  $h = gethost($host);
  die "$0: unknown host: $host\n" unless $h;

  if ( @{$h->addr_list} > 1 ) {
    my $i;
    for my $addr ( @{$h->addr_list} ) {
      $ipadr = inet_ntoa($addr);
      printf "$host \taddr #%d is [%s]\n", $i++, $ipadr if $debug;
    }
  } else {
    $ipadr = inet_ntoa($h->addr);
    printf "$host \taddress is [%s]\n", $ipadr if $debug;
  }
  ip2hex($ipadr);
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub readpxedir {

  # read all files in pxedir and add them to different arrays

  opendir(DIR, $pxedir) || die "Can't opendir $pxedir: $!";
  foreach (readdir(DIR)) {
    next if /^\./;
    next if /~$/;
    next if /\.bak$/;
    if (/^(default|[0-9A-F]+)$/) { push @enabled,   $_ ; next}
    if (/\.tmpl$/)               { push @templates, $_ ; next}
    if (/\.disable$/) {
      my $filename=(split (/\./,$_))[0];
      if (-f "$pxedir/$filename") {
        warn "Skipping $_ as disabled host because also enabled.\n" if $verbose;
      } else {
        push @disabled, $_;
      }
      next;
    }
    push @other, $_;
  }
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub lsdir {

# -ld list only disabled hosts
# -le list only enabled hosts
# -lt list only templates
# -lo list only "other", i.e that does not match templates or hosts
# -lg list by goups (enabled, disabled, templates, others)
# -l[detog] <pattern> list matching pattern

  my ($h,$n,$host,$iaddr,$filename,$type);

  @patterns = @_; # a global variable

  readpxedir();

  # create list which entries we want to list
  @allfiles = (@enabled,@disabled,@templates,@other);
  $opt_d and @allfiles = @disabled;
  $opt_e and @allfiles = @enabled;
  $opt_t and @allfiles = @templates;
  $opt_o and @allfiles = @other;
  $opt_g and @allfiles = (@enabled,@disabled,@templates,@other);

  # map all entries (in HEX) to hostname or IP
  foreach $filename (@allfiles) {
    undef $host;
    undef $type;

    if ($filename =~ /^default(.disable)?$/) {
      $host = $filename;
      $type = '[DEFAULT]';
    }
    if ($filename =~ /\.tmpl$/) {
      $host = "$filename";
      $type = '[Template]';
    }

    if ($filename =~ /^01-[0-9A-F-]{17}$/i) {
      $host = "$filename";
      $type = '[MAC address]';
    }

    if (($filename =~ /^[0-9A-F]+/) && ($filename !~ /^01-/) ) {
      my $hexstrip = (split /\./,$filename)[0]; # remove .disable if necessary
      $n = $hexstrip;
      # hex to ip/subnet address
      while ( length $n ) {
        $host = sprintf( "%s%d" ,$host?"$host.":$host,
                 (hex substr $n,0,1,"" ) * 16 + (hex substr $n,0,1,""));
      }
      if ( $host and ( length($hexstrip) < 8) ) {
        $host = "Subnet: $host/". length($hexstrip)*4
      } else {
        # ip to hostname
        $iaddr = inet_aton($host);
        if ($h = gethostbyaddr($iaddr, AF_INET)) {
          $host = $h->name;
          $host =~ s/^([^.]+).*/$1/; # strip domain from FQDN so we have short hostnames
        }
      }
    }

    if ( !$host ) {
      $host = $filename;
      $type = '[Other]';
    }

    $hexname{$host} = $filename;
    $hname{$filename}= $host;
    $type{$filename} = $type if $type;
  }

  if ($opt_g) { # print in group, sorted inside each group
    prtsorted(@enabled);
    prtsorted(@disabled);
    prtsorted(@templates);
    prtsorted(@other);
    exit 0;
  }

  prtsorted(keys %hname);
  exit 0;
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub prtsorted {

  my @list = @_;

  # sort by readable host names
  @list = sort { $hname{$a} cmp $hname{$b} } @list;

  foreach (@list) {
    printpxe ($hname{$_},$_, $type{$_});
  }
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub printpxe {

  my ($host,$hex, $type) = @_;
  my ($kernelname,$append);

  $match = (@patterns) ? 0: 1; # set match to 1 if no pattern is given
  foreach (@patterns) {
    $match = 1 if $host =~ /$_/;
  }
  return unless $match; # do not print entries if no pattern matches

  # read pxe config file for a host
  undef $kernelname;
  open (CFG,"$pxedir/$hex") || die "$! $@\n";
  while (<CFG>) {
    next if /^#/;
    /\bkernel\s+(\S+)/ and $kernelname = $1;
    /\b(localboot.+)/ and $kernelname = $1;
    /\bappend\s+(.+)/ and $append = $1;
  }
  close (CFG);

  if ($opt_q) {
    printf "%-16.16s $pxedir/$hex \n",$host;
  } elsif ($opt_l && ! $opt_L) {
    if ($append =~ /FAI_ACTION=(\S+)/) {
      $append = $1;
    } else {
      $append = 'NOACTION';
    }
#   printf "%-16.16s $append $kernelname %-8s\n",$host,$hex;
    printf "%-26.26s  %-22.22s $append $kernelname\n",$type?$type:$host,$hex;
  } else {
    printf "%s %s $kernelname $append\n",$type?$type:$host,$hex;
  }

  undef $append;
  undef $kernelname;
}

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub usage {

  &HELP_MESSAGE;
  exit 0;
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub HELP_MESSAGE {

  print << "EOM";
 Please read the manual pages fai-chboot(8).
EOM
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub mkpxecfg {

  my ($host,$kernel,$rootfs,$initrd) = @_;
  my ($ipadr,$hex) = host2hex($host);

  warn "$host has $ipadr in hex $hex\n" if $verbose;
  if (-f "$pxedir/$hex.disable") {
    unlink "$pxedir/$hex.disable";
    print "removed old $pxedir/$hex.disable\n";
  }
  warn "Writing file $pxedir/$hex for $host\n" if $verbose;
  return if $opt_n;

  if ($opt_p && -e "$pxedir/$hex") {
    warn "WARNING: $pxedir/$hex already exists.\nSkipping file creation. ";
    return;
  }
  open (FILE,"> $pxedir/$hex") or warn "$0 $@ $!";
  print FILE << "EOM";
default fai-generated

label fai-generated
$kernel

# generated by fai-chboot for host $host with IP $ipadr
EOM

  $append="append $initrd $bootprot $rootfs $opt_k $flags $action\n";
  print FILE "$append" unless ($append =~ /append\s+$/);
  print FILE "IPAPPEND 6\n" if $opt_P;
  close FILE;
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub disable {

  # rename network config file
  my ($host) = shift;
  my ($ipadr,$hex) = host2hex($host);
  if (! -e "$pxedir/$hex") {
    print "$host ($hex) is not enabled\n";
    return;
  }
  print "disable pxe config for $host in hex $hex\n" if $verbose;
  return if $opt_n;
  rename "$pxedir/$hex","$pxedir/$hex.disable" or $error .= "\nRename for $hex failed. $! $@";
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub enable {

  # rename network config file
  my ($host) = shift;
  my ($ipadr,$hex) = host2hex($host);

  -e "$pxedir/$hex" and print "$host ($hex) is already enabled\n" and return;
  if (! -e "$pxedir/$hex.disable") {
    print "$host ($hex) is not disabled\n";
    return;
  }

  print "reenable pxe config for $host in hex $hex\n" if $verbose;
  return if $opt_n;
  rename "$pxedir/$hex.disable","$pxedir/$hex" or $error .= "\nRename for $hex failed. $! $@";
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub docopy {

  my ($srcfile, $pxedir, $desthex, $desthost, $ipadr) = @_;
  open (SOURCE, "$srcfile");
  open (DEST, ">$pxedir/$desthex") || die "Can't opendir $pxedir: $!";
  while (<SOURCE>) {
    s/\$IP/$ipadr/g;
    s/\$HOST/$desthost/g;
    print DEST $_;
  }
  print DEST "\n# template generated by fai-chboot for host $desthost with IP $ipadr from source $srcfile\n";
  close SOURCE;
  close DEST;
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
sub tcopy {

  my ($srchost,$desthost) = @_;
  my ($ipadr,$srcfile,$srchex,$desthex);

  if (gethost($srchost)) {
    ($ipadr,$srchex) = host2hex($srchost);

    if (-e "$pxedir/$srchex") {
      $srcfile = "$srchex";
    } elsif (-e "$pxedir/$srchex.disable") {
      $srcfile = "$srchex.disable";
    } elsif (-e "$pxedir/$srchost" ) {
      $srcfile = "$srchost";
    } elsif (-e "$pxedir/$srchost.tmpl" ) {
      $srcfile = "$srchost.tmpl";
    } else {
      warn "Source file for $srchost ($srchex) not available\n";
      return;
    }
  } elsif ( -e "$pxedir/$srchost") {
      $srcfile = "$srchost";
  } elsif ( -e "$pxedir/$srchost.tmpl") {
      $srcfile = "$srchost.tmpl";
  } else {
      warn "Source file for $srchost not available\n";
      return;
  }
  if ($desthost =~ /\.tmpl$/) {
    if (-e "$pxedir/$desthost") {
      warn "Template $desthost already exist. Copying aborted.\n";
      return;
    }
    print "copy pxe config from $srchost to template $desthost\n" if $verbose;
    docopy("$pxedir/$srcfile",$pxedir,$desthost,$desthost,$ipadr);
  } else {
    ($ipadr,$desthex) = host2hex($desthost);
    if (-f "$pxedir/$desthex.disable") {
      unlink "$pxedir/$desthex.disable";
      print "removed old $pxedir/$desthex.disable\n";
    }
    print "copy pxe config from $srchost to $desthost, filenames: $srcfile -> $desthex\n" if $verbose;
    docopy("$pxedir/$srcfile",$pxedir,$desthex,$desthost,$ipadr);
  }
}
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
getopts('gBc:C:D:eEdhnvlLiIpf:Fk:Ss:tu:U:oPqa:') || usage;
$opt_h and usage;

$opt_n and $opt_v = 1;
$opt_v and $verbose = 1;
$cfdir = $opt_C || $ENV{'FAI_ETC_DIR'} || '/etc/fai';
-d $cfdir || die "ERROR: $cfdir does not exists.";
$opt_L and $opt_l = 1;
$opt_l or ( @ARGV ) or usage;

($opt_B and $opt_F) && die "ERROR: use only one option out of -B and -F\n";
($opt_S and $opt_I) && die "ERROR: use only one option out of -I and -S\n";
($opt_S and $opt_a) && die "ERROR: use only one option out of -S and -a\n";
($opt_I and $opt_a) && die "ERROR: use only one option out of -I and -a\n";


#TODO: also -e, -r and -c can't be used together

if ($opt_U && $opt_U !~ m#/$#) {
    die "URL $opt_U must end with a slash\n";
}

# read the nfsroot variable; a little bit ugly, but it works
$nfsroot = `. $cfdir/nfsroot.conf 2>/dev/null; echo \$NFSROOT`;
chomp $nfsroot;
$nfsroot = '/srv/fai/nfsroot' unless $nfsroot;

$nfsroot_server = `. $cfdir/nfsroot.conf 2>/dev/null; echo \$NFSROOT_SERVER`;
chomp $nfsroot_server;
$nfsroot_server = 0 unless $nfsroot_server;

$tftproot = `. $cfdir/nfsroot.conf 2>/dev/null; echo \$TFTPROOT`;
chomp $tftproot;
$tftproot = '/srv/tftp/fai' unless $tftproot;

$pxedir = $opt_D || "$tftproot/pxelinux.cfg";

(-d $pxedir) || die "PXE directory $pxedir does not exist.";

$opt_l and lsdir(@ARGV);
$opt_q and lsdir(@ARGV);

if ($opt_d) {
  die "Missing host name(s). Can't disable network booting.\n" unless @ARGV;
  foreach (@ARGV) {
    disable($_);
  }
  $error and die "$0: $error\n";
  exit 0;
}

if ($opt_c) {
  die "Missing destination host name(s). Can't copy.\n" unless @ARGV;
  # copy a template config to multiple hosts
  foreach (@ARGV) {
    tcopy($opt_c,$_);
  }
  $error and die "$0: $error\n";
  exit 0;
}

if ($opt_e) {
  die "Missing host name(s). Can't reenable network booting.\n" unless @ARGV;
  foreach (@ARGV) {
    enable($_);
  }
  $error and die "$0: $error\n";
  exit 0;
}

if ($opt_S) {
  $opt_i = 1;
  $action="FAI_ACTION=sysinfo";
}
if ($opt_I) {
  $opt_i = 1;
  $action="FAI_ACTION=install";
}
if ($opt_a) {
  $opt_i = 1;
  $action="FAI_ACTION=$opt_a";
}

if ($opt_i || $opt_s) {
  $kernelsuffix = (glob "$nfsroot/boot/vmlinuz*$opt_s")[-1];
  $kernelsuffix //= (glob "$tftproot/vmlinuz*$opt_s")[-1];
  $kernelsuffix=~ s/.+vmlinuz-//;
  die "No kernel found matching $tftproot/vmlinuz*$opt_s\n" unless $kernelsuffix;
}

if ($opt_i) {

  my $bopt;
  -d "$nfsroot/lib/modules/$kernelsuffix/kernel/fs/aufs" and $bopt="aufs";
  -d "$nfsroot/lib/modules/$kernelsuffix/kernel/fs/overlayfs" and $bopt="rootovl";

  # create config so host will boot the install kernel
  $rootfs_pre = ($nfsroot_server) ? "nfs:$nfsroot_server:" : "";
  $kernelname = "kernel ${opt_U}vmlinuz-$kernelsuffix";
  $initrd     = "initrd=${opt_U}initrd.img-$kernelsuffix";
  $rootfs     = "root=${rootfs_pre}$nfsroot:vers=3 $bopt";
  $bootprot   = "ip=dhcp ";

} elsif ($opt_o) {
  $kernelname = 'localboot -1';
  $rootfs   = '';
  $bootprot = '';
  $flags    = '';
} else {
  $kernelname = shift;
  $kernelname = "kernel $kernelname";
#  $rootfs = shift or die "No rootfs specified.\n";
}

$opt_F and $opt_f="verbose,sshd,createvt";
$opt_B and $opt_f="verbose,sshd,reboot";
$opt_E and $opt_f="$opt_f,initial";
$opt_f and $flags="FAI_FLAGS=$opt_f";
$opt_u and $flags.=" FAI_CONFIG_SRC=$opt_u"; # set -u as FAI_CONFIG_SRC

die "No host specified.\n" unless @ARGV;
warn "Booting $kernelname\n" if $verbose;
warn " append $initrd $bootprot $opt_k\n" if ( $verbose and ("$initrd $bootprot $opt_k" !~ /^\s+$/));
warn "   $flags\n\n" if ($verbose and $flags);
$opt_k && print "Kernel parameters: $opt_k\n";

foreach (@ARGV) { mkpxecfg($_,$kernelname,$rootfs,$initrd); }