为什么我的解密功能的工作吗？

Question

此不写入由我;它是由人谁传递下来给我。我失去了与代码的作者联系。我一直用这个代码了几年，刚才意识到这个错误。看来，字母序列rkey1搅乱输出。

例如turkey1输出作为解密作为tur79y1。此Perl代码应该输出turkey1和不tur79y1：

$String = "turkey1";
$e = &encode_escaped(&palace_encrypt($String));
$d = &palace_decrypt(&decode_escaped("'\"".$e."\"'"));
print $d."<br>\n";

KEY REMOVED BY OWNER


sub palace_decrypt
{
    local $lastchar = 0;
    local $rc = 0;
    local @bs;
    for($i=length($_[0])-1; $i>=0; $i--) {
        local $tmp = ord(substr($_[0], $i, 1));
        $bs[$i] = $tmp ^ $palace_key[$rc++] ^ $lastchar;
        $lastchar = $tmp ^ $palace_key[$rc++];
        }

    return join("", map { chr($_) } @bs);
}

sub decode_escaped
{
    $_[0] =~ m/\"(.*)\"/;
    local $str = $1;
    $str =~ s/\\\\/\0/g;
    $str =~ s/\\"/"/g;
    $str =~ s/\\(..)/pack("c",hex($1))/ge;
    $str =~ s/\0/\\/g;
    return $str;
}


sub palace_encrypt
{
    local $lastchar = 0;
    local $rc = 0;
    local @bs;
    for($i=length($_[0])-1; $i>=0; $i--) {
        local $b = ord(substr($_[0], $i, 1));
        $bs[$i] = $b ^ $palace_key[$rc++] ^ $lastchar;
        $lastchar = $bs[$i] ^ $palace_key[$rc++];
        }
    return join("", map { chr($_) } @bs);
}

sub encode_escaped
{
    local $str = $_[0];
    $str =~ s/\\/\\\\/g;
    $str =~ s/([^A-Za-z0-9\.\\])/sprintf("\\%2.2X", ord($1))/ge;

    return $str;
}

Answer 1

您的问题是，你的decode_escaped并不完全撤消什么encode_escaped一样。用下面这应该解决您的问题，请更换。

sub decode_escaped
{
    $_[0] =~ m/\"(.*)\"/;
    local @str = split /(\\\\)/, $1;
    foreach (@str) {
        s/\\"/"/g;
        s/\\(..)/chr(hex($1))/ge;
        s/\\\\/\\/;
    }
    return join '', @str;
}