# Pack File

File with encryption support used to archive and manage other files.

{% tabs %}
{% tab title="File Structure" %}

```csharp
// Header
30  char[]  Signature     //JoyMax File Manager!\n
4   byte[]  Version       //2.0.0.1
1   byte    IsEncrypted
16  byte[]  Checksum      // Used to test the blowfish key
205 byte[]  Reserved

// Block; 20 x 128 = 2560 bytes needs to be decrypted before reading if required
for (i = 0; i < 20; i++)
{
    // Entry
    1   byte    Type        // 0 = Empty, 1 = Folder, 2  = File
    89  char[]  Name
    8   ulong   CreateTime  // Windows time format
    8   ulong   ModifyTime  // Windows time format
    8   ulong   Position    // Position of data for files, position of the Block for folders
    4   uint    Size        // Size of files
    8   ulong   NextBlock   // Position of the next block in the chain from current directory
    2   byte[]  Padding     // So blowfish can be used directly on the struct
}
```

{% endtab %}

{% tab title="ImHex" %}

```c
struct PackFileHeader
{
    char Signature[30];
    u8 Version[4];
    bool IsEncrypted;
    u8 Checksum[16];
    u8 Reserved[205];
};

struct PackFileEntry
{
    u8 Type;
    char Name[89];
    u64 CreateTime;
    u64 ModifyTime;
    u64 Position;
    u32 Size;
    u64 NextChain;
    u16 Padding;
};

struct PackFileBlock
{
    PackFileEntry Entries[20];    
};

struct PackFile
{
    PackFileHeader Header;
    if(!Header.IsEncrypted)
    {
        PackFileBlock RootBlock @ 256;
    }
};

PackFile file @ 0;
```

{% endtab %}
{% endtabs %}