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1#!/usr/bin/env perl
2# ***************************************************************************
3# *                                  _   _ ____  _
4# *  Project                     ___| | | |  _ \| |
5# *                             / __| | | | |_) | |
6# *                            | (__| |_| |  _ <| |___
7# *                             \___|\___/|_| \_\_____|
8# *
9# * Copyright (C) 1998 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
10# *
11# * This software is licensed as described in the file COPYING, which
12# * you should have received as part of this distribution. The terms
13# * are also available at https://curl.se/docs/copyright.html.
14# *
15# * You may opt to use, copy, modify, merge, publish, distribute and/or sell
16# * copies of the Software, and permit persons to whom the Software is
17# * furnished to do so, under the terms of the COPYING file.
18# *
19# * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
20# * KIND, either express or implied.
21# *
22# ***************************************************************************
23# This Perl script creates a fresh ca-bundle.crt file for use with libcurl.
24# It downloads certdata.txt from Mozilla's source tree (see URL below),
25# then parses certdata.txt and extracts CA Root Certificates into PEM format.
26# These are then processed with the OpenSSL commandline tool to produce the
27# final ca-bundle.crt file.
28# The script is based on the parse-certs script written by Roland Krikava.
29# This Perl script works on almost any platform since its only external
30# dependency is the OpenSSL commandline tool for optional text listing.
31# Hacked by Guenter Knauf.
32#
33use Encode;
34use Getopt::Std;
35use MIME::Base64;
36use strict;
37use warnings;
38use vars qw($opt_b $opt_d $opt_f $opt_h $opt_i $opt_k $opt_l $opt_m $opt_n $opt_p $opt_q $opt_s $opt_t $opt_u $opt_v $opt_w);
39use List::Util;
40use Text::Wrap;
41use Time::Local;
42my $MOD_SHA = "Digest::SHA";
43eval "require $MOD_SHA";
44if ($@) {
45  $MOD_SHA = "Digest::SHA::PurePerl";
46  eval "require $MOD_SHA";
47}
48eval "require LWP::UserAgent";
49
50my %urls = (
51  'nss' =>
52    'https://hg.mozilla.org/projects/nss/raw-file/default/lib/ckfw/builtins/certdata.txt',
53  'central' =>
54    'https://hg.mozilla.org/mozilla-central/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt',
55  'beta' =>
56    'https://hg.mozilla.org/releases/mozilla-beta/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt',
57  'release' =>
58    'https://hg.mozilla.org/releases/mozilla-release/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt',
59);
60
61$opt_d = 'release';
62
63# If the OpenSSL commandline is not in search path you can configure it here!
64my $openssl = 'openssl';
65
66my $version = '1.28';
67
68$opt_w = 76; # default base64 encoded lines length
69
70# default cert types to include in the output (default is to include CAs which may issue SSL server certs)
71my $default_mozilla_trust_purposes = "SERVER_AUTH";
72my $default_mozilla_trust_levels = "TRUSTED_DELEGATOR";
73$opt_p = $default_mozilla_trust_purposes . ":" . $default_mozilla_trust_levels;
74
75my @valid_mozilla_trust_purposes = (
76  "DIGITAL_SIGNATURE",
77  "NON_REPUDIATION",
78  "KEY_ENCIPHERMENT",
79  "DATA_ENCIPHERMENT",
80  "KEY_AGREEMENT",
81  "KEY_CERT_SIGN",
82  "CRL_SIGN",
83  "SERVER_AUTH",
84  "CLIENT_AUTH",
85  "CODE_SIGNING",
86  "EMAIL_PROTECTION",
87  "IPSEC_END_SYSTEM",
88  "IPSEC_TUNNEL",
89  "IPSEC_USER",
90  "TIME_STAMPING",
91  "STEP_UP_APPROVED"
92);
93
94my @valid_mozilla_trust_levels = (
95  "TRUSTED_DELEGATOR",    # CAs
96  "NOT_TRUSTED",          # Don't trust these certs.
97  "MUST_VERIFY_TRUST",    # This explicitly tells us that it ISN'T a CA but is otherwise ok. In other words, this should tell the app to ignore any other sources that claim this is a CA.
98  "TRUSTED"               # This cert is trusted, but only for itself and not for delegates (i.e. it is not a CA).
99);
100
101my $default_signature_algorithms = $opt_s = "MD5";
102
103my @valid_signature_algorithms = (
104  "MD5",
105  "SHA1",
106  "SHA256",
107  "SHA384",
108  "SHA512"
109);
110
111$0 =~ s@.*(/|\\)@@;
112$Getopt::Std::STANDARD_HELP_VERSION = 1;
113getopts('bd:fhiklmnp:qs:tuvw:');
114
115if(!defined($opt_d)) {
116    # to make plain "-d" use not cause warnings, and actually still work
117    $opt_d = 'release';
118}
119
120# Use predefined URL or else custom URL specified on command line.
121my $url;
122if(defined($urls{$opt_d})) {
123  $url = $urls{$opt_d};
124  if(!$opt_k && $url !~ /^https:\/\//i) {
125    die "The URL for '$opt_d' is not HTTPS. Use -k to override (insecure).\n";
126  }
127}
128else {
129  $url = $opt_d;
130}
131
132my $curl = `curl -V`;
133
134if ($opt_i) {
135  print ("=" x 78 . "\n");
136  print "Script Version                   : $version\n";
137  print "Perl Version                     : $]\n";
138  print "Operating System Name            : $^O\n";
139  print "Getopt::Std.pm Version           : ${Getopt::Std::VERSION}\n";
140  print "Encode::Encoding.pm Version      : ${Encode::Encoding::VERSION}\n";
141  print "MIME::Base64.pm Version          : ${MIME::Base64::VERSION}\n";
142  print "LWP::UserAgent.pm Version        : ${LWP::UserAgent::VERSION}\n" if($LWP::UserAgent::VERSION);
143  print "LWP.pm Version                   : ${LWP::VERSION}\n" if($LWP::VERSION);
144  print "Digest::SHA.pm Version           : ${Digest::SHA::VERSION}\n" if ($Digest::SHA::VERSION);
145  print "Digest::SHA::PurePerl.pm Version : ${Digest::SHA::PurePerl::VERSION}\n" if ($Digest::SHA::PurePerl::VERSION);
146  print ("=" x 78 . "\n");
147}
148
149sub warning_message() {
150  if ( $opt_d =~ m/^risk$/i ) { # Long Form Warning and Exit
151    print "Warning: Use of this script may pose some risk:\n";
152    print "\n";
153    print "  1) If you use HTTP URLs they are subject to a man in the middle attack\n";
154    print "  2) Default to 'release', but more recent updates may be found in other trees\n";
155    print "  3) certdata.txt file format may change, lag time to update this script\n";
156    print "  4) Generally unwise to blindly trust CAs without manual review & verification\n";
157    print "  5) Mozilla apps use additional security checks aren't represented in certdata\n";
158    print "  6) Use of this script will make a security engineer grind his teeth and\n";
159    print "     swear at you.  ;)\n";
160    exit;
161  } else { # Short Form Warning
162    print "Warning: Use of this script may pose some risk, -d risk for more details.\n";
163  }
164}
165
166sub HELP_MESSAGE() {
167  print "Usage:\t${0} [-b] [-d<certdata>] [-f] [-i] [-k] [-l] [-n] [-p<purposes:levels>] [-q] [-s<algorithms>] [-t] [-u] [-v] [-w<l>] [<outputfile>]\n";
168  print "\t-b\tbackup an existing version of ca-bundle.crt\n";
169  print "\t-d\tspecify Mozilla tree to pull certdata.txt or custom URL\n";
170  print "\t\t  Valid names are:\n";
171  print "\t\t    ", join( ", ", map { ( $_ =~ m/$opt_d/ ) ? "$_ (default)" : "$_" } sort keys %urls ), "\n";
172  print "\t-f\tforce rebuild even if certdata.txt is current\n";
173  print "\t-i\tprint version info about used modules\n";
174  print "\t-k\tallow URLs other than HTTPS, enable HTTP fallback (insecure)\n";
175  print "\t-l\tprint license info about certdata.txt\n";
176  print "\t-m\tinclude meta data in output\n";
177  print "\t-n\tno download of certdata.txt (to use existing)\n";
178  print wrap("\t","\t\t", "-p\tlist of Mozilla trust purposes and levels for certificates to include in output. Takes the form of a comma separated list of purposes, a colon, and a comma separated list of levels. (default: $default_mozilla_trust_purposes:$default_mozilla_trust_levels)"), "\n";
179  print "\t\t  Valid purposes are:\n";
180  print wrap("\t\t    ","\t\t    ", join( ", ", "ALL", @valid_mozilla_trust_purposes ) ), "\n";
181  print "\t\t  Valid levels are:\n";
182  print wrap("\t\t    ","\t\t    ", join( ", ", "ALL", @valid_mozilla_trust_levels ) ), "\n";
183  print "\t-q\tbe really quiet (no progress output at all)\n";
184  print wrap("\t","\t\t", "-s\tcomma separated list of certificate signatures/hashes to output in plain text mode. (default: $default_signature_algorithms)\n");
185  print "\t\t  Valid signature algorithms are:\n";
186  print wrap("\t\t    ","\t\t    ", join( ", ", "ALL", @valid_signature_algorithms ) ), "\n";
187  print "\t-t\tinclude plain text listing of certificates\n";
188  print "\t-u\tunlink (remove) certdata.txt after processing\n";
189  print "\t-v\tbe verbose and print out processed CAs\n";
190  print "\t-w <l>\twrap base64 output lines after <l> chars (default: ${opt_w})\n";
191  exit;
192}
193
194sub VERSION_MESSAGE() {
195  print "${0} version ${version} running Perl ${]} on ${^O}\n";
196}
197
198warning_message() unless ($opt_q || $url =~ m/^(ht|f)tps:/i );
199HELP_MESSAGE() if ($opt_h);
200
201sub report($@) {
202  my $output = shift;
203
204  print STDERR $output . "\n" unless $opt_q;
205}
206
207sub is_in_list($@) {
208  my $target = shift;
209
210  return defined(List::Util::first { $target eq $_ } @_);
211}
212
213# Parses $param_string as a case insensitive comma separated list with optional whitespace
214# validates that only allowed parameters are supplied
215sub parse_csv_param($$@) {
216  my $description = shift;
217  my $param_string = shift;
218  my @valid_values = @_;
219
220  my @values = map {
221    s/^\s+//;  # strip leading spaces
222    s/\s+$//;  # strip trailing spaces
223    uc $_      # return the modified string as upper case
224  } split( ',', $param_string );
225
226  # Find all values which are not in the list of valid values or "ALL"
227  my @invalid = grep { !is_in_list($_,"ALL",@valid_values) } @values;
228
229  if ( scalar(@invalid) > 0 ) {
230    # Tell the user which parameters were invalid and print the standard help message which will exit
231    print "Error: Invalid ", $description, scalar(@invalid) == 1 ? ": " : "s: ", join( ", ", map { "\"$_\"" } @invalid ), "\n";
232    HELP_MESSAGE();
233  }
234
235  @values = @valid_values if ( is_in_list("ALL",@values) );
236
237  return @values;
238}
239
240sub sha256 {
241  my $result;
242  if ($Digest::SHA::VERSION || $Digest::SHA::PurePerl::VERSION) {
243    open(FILE, $_[0]) or die "Can't open '$_[0]': $!";
244    binmode(FILE);
245    $result = $MOD_SHA->new(256)->addfile(*FILE)->hexdigest;
246    close(FILE);
247  } else {
248    # Use OpenSSL command if Perl Digest::SHA modules not available
249    $result = `"$openssl" dgst -r -sha256 "$_[0]"`;
250    $result =~ s/^([0-9a-f]{64}) .+/$1/is;
251  }
252  return $result;
253}
254
255
256sub oldhash {
257  my $hash = "";
258  open(C, "<$_[0]") || return 0;
259  while(<C>) {
260    chomp;
261    if($_ =~ /^\#\# SHA256: (.*)/) {
262      $hash = $1;
263      last;
264    }
265  }
266  close(C);
267  return $hash;
268}
269
270if ( $opt_p !~ m/:/ ) {
271  print "Error: Mozilla trust identifier list must include both purposes and levels\n";
272  HELP_MESSAGE();
273}
274
275(my $included_mozilla_trust_purposes_string, my $included_mozilla_trust_levels_string) = split( ':', $opt_p );
276my @included_mozilla_trust_purposes = parse_csv_param( "trust purpose", $included_mozilla_trust_purposes_string, @valid_mozilla_trust_purposes );
277my @included_mozilla_trust_levels = parse_csv_param( "trust level", $included_mozilla_trust_levels_string, @valid_mozilla_trust_levels );
278
279my @included_signature_algorithms = parse_csv_param( "signature algorithm", $opt_s, @valid_signature_algorithms );
280
281sub should_output_cert(%) {
282  my %trust_purposes_by_level = @_;
283
284  foreach my $level (@included_mozilla_trust_levels) {
285    # for each level we want to output, see if any of our desired purposes are included
286    return 1 if ( defined( List::Util::first { is_in_list( $_, @included_mozilla_trust_purposes ) } @{$trust_purposes_by_level{$level}} ) );
287  }
288
289  return 0;
290}
291
292my $crt = $ARGV[0] || 'ca-bundle.crt';
293(my $txt = $url) =~ s@(.*/|\?.*)@@g;
294
295my $stdout = $crt eq '-';
296my $resp;
297my $fetched;
298
299my $oldhash = oldhash($crt);
300
301report "SHA256 of old file: $oldhash";
302
303if(!$opt_n) {
304  report "Downloading $txt ...";
305
306  # If we have an HTTPS URL then use curl
307  if($url =~ /^https:\/\//i) {
308    if($curl) {
309      if($curl =~ /^Protocols:.* https( |$)/m) {
310        report "Get certdata with curl!";
311        my $proto = !$opt_k ? "--proto =https" : "";
312        my $quiet = $opt_q ? "-s" : "";
313        my @out = `curl -w %{response_code} $proto $quiet -o "$txt" "$url"`;
314        if(!$? && @out && $out[0] == 200) {
315          $fetched = 1;
316          report "Downloaded $txt";
317        }
318        else {
319          report "Failed downloading via HTTPS with curl";
320          if(-e $txt && !unlink($txt)) {
321            report "Failed to remove '$txt': $!";
322          }
323        }
324      }
325      else {
326        report "curl lacks https support";
327      }
328    }
329    else {
330      report "curl not found";
331    }
332  }
333
334  # If nothing was fetched then use LWP
335  if(!$fetched) {
336    if($url =~ /^https:\/\//i) {
337      report "Falling back to HTTP";
338      $url =~ s/^https:\/\//http:\/\//i;
339    }
340    if(!$opt_k) {
341      report "URLs other than HTTPS are disabled by default, to enable use -k";
342      exit 1;
343    }
344    report "Get certdata with LWP!";
345    if(!defined(${LWP::UserAgent::VERSION})) {
346      report "LWP is not available (LWP::UserAgent not found)";
347      exit 1;
348    }
349    my $ua  = new LWP::UserAgent(agent => "$0/$version");
350    $ua->env_proxy();
351    $resp = $ua->mirror($url, $txt);
352    if($resp && $resp->code eq '304') {
353      report "Not modified";
354      exit 0 if -e $crt && !$opt_f;
355    }
356    else {
357      $fetched = 1;
358      report "Downloaded $txt";
359    }
360    if(!$resp || $resp->code !~ /^(?:200|304)$/) {
361      report "Unable to download latest data: "
362        . ($resp? $resp->code . ' - ' . $resp->message : "LWP failed");
363      exit 1 if -e $crt || ! -r $txt;
364    }
365  }
366}
367
368my $filedate = $resp ? $resp->last_modified : (stat($txt))[9];
369my $datesrc = "as of";
370if(!$filedate) {
371    # mxr.mozilla.org gave us a time, hg.mozilla.org does not!
372    $filedate = time();
373    $datesrc="downloaded on";
374}
375
376# get the hash from the download file
377my $newhash= sha256($txt);
378
379if(!$opt_f && $oldhash eq $newhash) {
380    report "Downloaded file identical to previous run\'s source file. Exiting";
381    if($opt_u && -e $txt && !unlink($txt)) {
382        report "Failed to remove $txt: $!\n";
383    }
384    exit;
385}
386
387report "SHA256 of new file: $newhash";
388
389my $currentdate = scalar gmtime($filedate);
390
391my $format = $opt_t ? "plain text and " : "";
392if( $stdout ) {
393    open(CRT, '> -') or die "Couldn't open STDOUT: $!\n";
394} else {
395    open(CRT,">$crt.~") or die "Couldn't open $crt.~: $!\n";
396}
397print CRT <<EOT;
398##
399## Bundle of CA Root Certificates
400##
401## Certificate data from Mozilla ${datesrc}: ${currentdate} GMT
402##
403## This is a bundle of X.509 certificates of public Certificate Authorities
404## (CA). These were automatically extracted from Mozilla's root certificates
405## file (certdata.txt).  This file can be found in the mozilla source tree:
406## ${url}
407##
408## It contains the certificates in ${format}PEM format and therefore
409## can be directly used with curl / libcurl / php_curl, or with
410## an Apache+mod_ssl webserver for SSL client authentication.
411## Just configure this file as the SSLCACertificateFile.
412##
413## Conversion done with mk-ca-bundle.pl version $version.
414## SHA256: $newhash
415##
416
417EOT
418
419report "Processing  '$txt' ...";
420my $caname;
421my $certnum = 0;
422my $skipnum = 0;
423my $start_of_cert = 0;
424my @precert;
425my $cka_value;
426my $valid = 1;
427
428open(TXT,"$txt") or die "Couldn't open $txt: $!\n";
429while (<TXT>) {
430  if (/\*\*\*\*\* BEGIN LICENSE BLOCK \*\*\*\*\*/) {
431    print CRT;
432    print if ($opt_l);
433    while (<TXT>) {
434      print CRT;
435      print if ($opt_l);
436      last if (/\*\*\*\*\* END LICENSE BLOCK \*\*\*\*\*/);
437    }
438  }
439  elsif(/^# (Issuer|Serial Number|Subject|Not Valid Before|Not Valid After |Fingerprint \(MD5\)|Fingerprint \(SHA1\)):/) {
440      push @precert, $_;
441      $valid = 1;
442      next;
443  }
444  elsif(/^#|^\s*$/) {
445      undef @precert;
446      next;
447  }
448  chomp;
449
450  # Example:
451  # CKA_NSS_SERVER_DISTRUST_AFTER MULTILINE_OCTAL
452  # \062\060\060\066\061\067\060\060\060\060\060\060\132
453  # END
454
455  if (/^CKA_NSS_SERVER_DISTRUST_AFTER (CK_BBOOL CK_FALSE|MULTILINE_OCTAL)/) {
456      if($1 eq "MULTILINE_OCTAL") {
457          my @timestamp;
458          while (<TXT>) {
459              last if (/^END/);
460              chomp;
461              my @octets = split(/\\/);
462              shift @octets;
463              for (@octets) {
464                  push @timestamp, chr(oct);
465              }
466          }
467          # A trailing Z in the timestamp signifies UTC
468          if($timestamp[12] ne "Z") {
469              report "distrust date stamp is not using UTC";
470          }
471          # Example date: 200617000000Z
472          # Means 2020-06-17 00:00:00 UTC
473          my $distrustat =
474            timegm($timestamp[10] . $timestamp[11], # second
475                   $timestamp[8] . $timestamp[9],   # minute
476                   $timestamp[6] . $timestamp[7],   # hour
477                   $timestamp[4] . $timestamp[5],   # day
478                   ($timestamp[2] . $timestamp[3]) - 1, # month
479                   "20" . $timestamp[0] . $timestamp[1]); # year
480          if(time >= $distrustat) {
481              # not trusted anymore
482              $skipnum++;
483              report "Skipping: $caname is not trusted anymore" if ($opt_v);
484              $valid = 0;
485          }
486          else {
487              # still trusted
488          }
489      }
490      next;
491  }
492
493  # this is a match for the start of a certificate
494  if (/^CKA_CLASS CK_OBJECT_CLASS CKO_CERTIFICATE/) {
495    $start_of_cert = 1
496  }
497  if ($start_of_cert && /^CKA_LABEL UTF8 \"(.*)\"/) {
498    $caname = $1;
499  }
500  my %trust_purposes_by_level;
501  if ($start_of_cert && /^CKA_VALUE MULTILINE_OCTAL/) {
502    $cka_value="";
503    while (<TXT>) {
504      last if (/^END/);
505      chomp;
506      my @octets = split(/\\/);
507      shift @octets;
508      for (@octets) {
509        $cka_value .= chr(oct);
510      }
511    }
512  }
513  if(/^CKA_CLASS CK_OBJECT_CLASS CKO_NSS_TRUST/ && $valid) {
514    # now scan the trust part to determine how we should trust this cert
515    while (<TXT>) {
516      last if (/^#/);
517      if (/^CKA_TRUST_([A-Z_]+)\s+CK_TRUST\s+CKT_NSS_([A-Z_]+)\s*$/) {
518        if ( !is_in_list($1,@valid_mozilla_trust_purposes) ) {
519          report "Warning: Unrecognized trust purpose for cert: $caname. Trust purpose: $1. Trust Level: $2";
520        } elsif ( !is_in_list($2,@valid_mozilla_trust_levels) ) {
521          report "Warning: Unrecognized trust level for cert: $caname. Trust purpose: $1. Trust Level: $2";
522        } else {
523          push @{$trust_purposes_by_level{$2}}, $1;
524        }
525      }
526    }
527
528    if ( !should_output_cert(%trust_purposes_by_level) ) {
529      $skipnum ++;
530      report "Skipping: $caname" if ($opt_v);
531    } else {
532      my $data = $cka_value;
533      $cka_value = "";
534
535      if(!length($data)) {
536          # if empty, skip
537          next;
538      }
539      my $encoded = MIME::Base64::encode_base64($data, '');
540      $encoded =~ s/(.{1,${opt_w}})/$1\n/g;
541      my $pem = "-----BEGIN CERTIFICATE-----\n"
542              . $encoded
543              . "-----END CERTIFICATE-----\n";
544      print CRT "\n$caname\n";
545      print CRT @precert if($opt_m);
546      my $maxStringLength = length(decode('UTF-8', $caname, Encode::FB_CROAK | Encode::LEAVE_SRC));
547      if ($opt_t) {
548        foreach my $key (sort keys %trust_purposes_by_level) {
549           my $string = $key . ": " . join(", ", @{$trust_purposes_by_level{$key}});
550           $maxStringLength = List::Util::max( length($string), $maxStringLength );
551           print CRT $string . "\n";
552        }
553      }
554      print CRT ("=" x $maxStringLength . "\n");
555      if (!$opt_t) {
556        print CRT $pem;
557      } else {
558        my $pipe = "";
559        foreach my $hash (@included_signature_algorithms) {
560          $pipe = "|$openssl x509 -" . $hash . " -fingerprint -noout -inform PEM";
561          if (!$stdout) {
562            $pipe .= " >> $crt.~";
563            close(CRT) or die "Couldn't close $crt.~: $!";
564          }
565          open(TMP, $pipe) or die "Couldn't open openssl pipe: $!";
566          print TMP $pem;
567          close(TMP) or die "Couldn't close openssl pipe: $!";
568          if (!$stdout) {
569            open(CRT, ">>$crt.~") or die "Couldn't open $crt.~: $!";
570          }
571        }
572        $pipe = "|$openssl x509 -text -inform PEM";
573        if (!$stdout) {
574          $pipe .= " >> $crt.~";
575          close(CRT) or die "Couldn't close $crt.~: $!";
576        }
577        open(TMP, $pipe) or die "Couldn't open openssl pipe: $!";
578        print TMP $pem;
579        close(TMP) or die "Couldn't close openssl pipe: $!";
580        if (!$stdout) {
581          open(CRT, ">>$crt.~") or die "Couldn't open $crt.~: $!";
582        }
583      }
584      report "Parsing: $caname" if ($opt_v);
585      $certnum ++;
586      $start_of_cert = 0;
587    }
588    undef @precert;
589  }
590
591}
592close(TXT) or die "Couldn't close $txt: $!\n";
593close(CRT) or die "Couldn't close $crt.~: $!\n";
594unless( $stdout ) {
595    if ($opt_b && -e $crt) {
596        my $bk = 1;
597        while (-e "$crt.~${bk}~") {
598            $bk++;
599        }
600        rename $crt, "$crt.~${bk}~" or die "Failed to create backup $crt.~$bk}~: $!\n";
601    } elsif( -e $crt ) {
602        unlink( $crt ) or die "Failed to remove $crt: $!\n";
603    }
604    rename "$crt.~", $crt or die "Failed to rename $crt.~ to $crt: $!\n";
605}
606if($opt_u && -e $txt && !unlink($txt)) {
607  report "Failed to remove $txt: $!\n";
608}
609report "Done ($certnum CA certs processed, $skipnum skipped).";
610