And if the path has a space, we definitely need to protect $openssl.

tools/c_rehash.in

@@ -101,7 +101,7 @@ sub check_file {
 sub link_hash_cert {
 		my $fname = $_[0];
 		$fname =~ s/'/'\\''/g;
-		my ($hash, $fprint) = `$openssl x509 -hash -fingerprint -noout -in '$fname'`;
+		my ($hash, $fprint) = `"$openssl" x509 -hash -fingerprint -noout -in '$fname'`;
 		chomp $hash;
 		chomp $fprint;
 		$fprint =~ s/^.*=//;
@@ -132,7 +132,7 @@ sub link_hash_cert {
 sub link_hash_crl {
 		my $fname = $_[0];
 		$fname =~ s/'/'\\''/g;
-		my ($hash, $fprint) = `$openssl crl -hash -fingerprint -noout -in '$fname'`;
+		my ($hash, $fprint) = `"$openssl" crl -hash -fingerprint -noout -in '$fname'`;
 		chomp $hash;
 		chomp $fprint;
 		$fprint =~ s/^.*=//;