#!/usr/bin/perl


# Perl c_rehash script, scan all files in a directory
# and add symbolic links to their hash values.

my $openssl;

my $dir = "/usr/lib/ssl";
my $prefix = "/usr";

if(defined $ENV{OPENSSL}) {
$openssl = $ENV{OPENSSL};
} else {
$openssl = "openssl";
$ENV{OPENSSL} = $openssl;
}

my $pwd;
eval "require Cwd";
if (defined(&Cwd::getcwd)) {
$pwd=Cwd::getcwd();
} else {
$pwd=`pwd`; chomp($pwd);
}
my $path_delim = ($pwd =~ /^[a-z]\:/i) ? ';' : ':'; # DOS/Win32 or Unix delimiter?

$ENV{PATH} = "$prefix/bin" . ($ENV{PATH} ? $path_delim . $ENV{PATH} : ""); # prefix our path

if(! -x $openssl) {
my $found = 0;
foreach (split /$path_delim/, $ENV{PATH}) {
if(-x "$_/$openssl") {
$found = 1;
$openssl = "$_/$openssl";
last;
}
}
if($found == 0) {
print STDERR "c_rehash: rehashing skipped ('openssl' program not available)\n";
exit 0;
}
}

if(@ARGV) {
@dirlist = @ARGV;
} elsif($ENV{SSL_CERT_DIR}) {
@dirlist = split /$path_delim/, $ENV{SSL_CERT_DIR};
} else {
$dirlist[0] = "$dir/certs";
}

if (-d $dirlist[0]) {
chdir $dirlist[0];
$openssl="$pwd/$openssl" if (!-x $openssl);
chdir $pwd;
}

foreach (@dirlist) {
if(-d $_ and -w $_) {
hash_dir($_);
}
}

sub hash_dir {
my %hashlist;
print "Doing $_[0]\n";
chdir $_[0];
opendir(DIR, ".");
my @flist = readdir(DIR);
# Delete any existing symbolic links
foreach (grep {/^[\da-f]+\.r{0,1}\d+$/} @flist) {
if(-l $_) {
unlink $_;
}
}
closedir DIR;
FILE: foreach $fname (grep {/\.pem$|\.crt$/} @flist) {
# Check to see if certificates and/or CRLs present.
my ($cert, $crl) = check_file($fname);
if(!$cert && !$crl) {
($cert, $crl) = check_file("$openssl x509 -in \"$fname\" -inform der -outform pem | ");
if(!$cert && !$crl) {
print STDERR "WARNING: $fname does not contain a certificate or CRL: skipping\n";
next;
}
}
link_hash_cert($fname) if($cert);
link_hash_cert_old($fname) if($cert);
link_hash_crl($fname) if($crl);
}
}

sub check_file {
my ($is_cert, $is_crl) = (0,0);
my $fname = $_[0];
open IN, $fname;
while(<IN>) {
if(/^-----BEGIN (.*)-----/) {
my $hdr = $1;
if($hdr =~ /^(X509 |TRUSTED |)CERTIFICATE$/) {
$is_cert = 1;
last if($is_crl);
} elsif($hdr eq "X509 CRL") {
$is_crl = 1;
last if($is_cert);
}
}
}
close IN;
return ($is_cert, $is_crl);
}


# Link a certificate to its subject name hash value, each hash is of
# the form <hash>.<n> where n is an integer. If the hash value already exists
# then we need to up the value of n, unless its a duplicate in which
# case we skip the link. We check for duplicates by comparing the
# certificate fingerprints

sub link_hash_cert {
my $fname = $_[0];
my $hashopt = $_[1] || '-subject_hash';
$fname =~ s/'/'\\''/g;
my ($hash, $fprint) = `"$openssl" x509 $hashopt -fingerprint -noout -in "$fname"`;
chomp $hash;
chomp $fprint;
$fprint =~ s/^.*=//;
$fprint =~ tr/://d;
my $suffix = 0;
# Search for an unused hash filename
while(exists $hashlist{"$hash.$suffix"}) {
# Hash matches: if fingerprint matches its a duplicate cert
if($hashlist{"$hash.$suffix"} eq $fprint) {
print STDERR "WARNING: Skipping duplicate certificate $fname\n";
return;
}
$suffix++;
}
$hash .= ".$suffix";
print "$fname => $hash\n";
$symlink_exists=eval {symlink("",""); 1};
if ($symlink_exists) {
symlink $fname, $hash;
} else {
open IN,"<$fname" or die "can't open $fname for read";
open OUT,">$hash" or die "can't open $hash for write";
print OUT <IN>; # does the job for small text files
close OUT;
close IN;
}
$hashlist{$hash} = $fprint;
}

sub link_hash_cert_old {
link_hash_cert($_[0], '-subject_hash_old');
}

# Same as above except for a CRL. CRL links are of the form <hash>.r<n>

sub link_hash_crl {
my $fname = $_[0];
$fname =~ s/'/'\\''/g;
my ($hash, $fprint) = `"$openssl" crl -hash -fingerprint -noout -in '$fname'`;
if(!$hash || !fprint) {
($hash, $fprint) = `"$openssl" crl -hash -fingerprint -noout -in '$fname' -inform der`;
}
chomp $hash;
chomp $fprint;
$fprint =~ s/^.*=//;
$fprint =~ tr/://d;
my $suffix = 0;
# Search for an unused hash filename
while(exists $hashlist{"$hash.r$suffix"}) {
# Hash matches: if fingerprint matches its a duplicate cert
if($hashlist{"$hash.r$suffix"} eq $fprint) {
print STDERR "WARNING: Skipping duplicate CRL $fname\n";
return;
}
$suffix++;
}
$hash .= ".r$suffix";
print "$fname => $hash\n";
$symlink_exists=eval {symlink("",""); 1};
if ($symlink_exists) {
symlink $fname, $hash;
} else {
system ("cp", $fname, $hash);
}
$hashlist{$hash} = $fprint;
}