can anyone understand this?

Discuss how to write good code, break bad code, your current pet projects, or the best way to approach novel problems

can anyone understand this?

Post by alibaba42 on Fri Dec 02, 2011 12:52 pm
([msg=63152]see can anyone understand this?[/msg])

hi guys, was wondering if anyone understands this javascript:

Code: Select all
//--------------------------------------------------------------------------------------------------
//
// stage 2 of 3
//
// challenge:
//   reveal the solution within VM.mem
//
// disclaimer:
//   tested in ie 9, firefox 6, chrome 14 and v8 shell (http://code.google.com/apis/v8/build.html),
//   other javascript implementations may or may not work.
//
//--------------------------------------------------------------------------------------------------

var VM = {
 
  cpu: {
    ip: 0x00,
   
    r0: 0x00,
    r1: 0x00,
    r2: 0x00,
    r3: 0x00,
   
    cs: 0x00,
    ds: 0x10,
   
    fl: 0x00,
   
    firmware: [0xd2ab1f05, 0xda13f110]
  },
 
  mem: [
    0x31, 0x04, 0x33, 0xaa, 0x40, 0x02, 0x80, 0x03, 0x52, 0x00, 0x72, 0x01, 0x73, 0x01, 0xb2, 0x50,
    0x30, 0x14, 0xc0, 0x01, 0x80, 0x00, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   
    0x98, 0xab, 0xd9, 0xa1, 0x9f, 0xa7, 0x83, 0x83, 0xf2, 0xb1, 0x34, 0xb6, 0xe4, 0xb7, 0xca, 0xb8,
    0xc9, 0xb8, 0x0e, 0xbd, 0x7d, 0x0f, 0xc0, 0xf1, 0xd9, 0x03, 0xc5, 0x3a, 0xc6, 0xc7, 0xc8, 0xc9,
    0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9,
    0xda, 0xdb, 0xa9, 0xcd, 0xdf, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
    0x26, 0xeb, 0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9,
    0x7d, 0x1f, 0x15, 0x60, 0x4d, 0x4d, 0x52, 0x7d, 0x0e, 0x27, 0x6d, 0x10, 0x6d, 0x5a, 0x06, 0x56,
    0x47, 0x14, 0x42, 0x0e, 0xb6, 0xb2, 0xb2, 0xe6, 0xeb, 0xb4, 0x83, 0x8e, 0xd7, 0xe5, 0xd4, 0xd9,
    0xc3, 0xf0, 0x80, 0x95, 0xf1, 0x82, 0x82, 0x9a, 0xbd, 0x95, 0xa4, 0x8d, 0x9a, 0x2b, 0x30, 0x69,
    0x4a, 0x69, 0x65, 0x55, 0x1c, 0x7b, 0x69, 0x1c, 0x6e, 0x04, 0x74, 0x35, 0x21, 0x26, 0x2f, 0x60,
    0x03, 0x4e, 0x37, 0x1e, 0x33, 0x54, 0x39, 0xe6, 0xba, 0xb4, 0xa2, 0xad, 0xa4, 0xc5, 0x95, 0xc8,
    0xc1, 0xe4, 0x8a, 0xec, 0xe7, 0x92, 0x8b, 0xe8, 0x81, 0xf0, 0xad, 0x98, 0xa4, 0xd0, 0xc0, 0x8d,
    0xac, 0x22, 0x52, 0x65, 0x7e, 0x27, 0x2b, 0x5a, 0x12, 0x61, 0x0a, 0x01, 0x7a, 0x6b, 0x1d, 0x67,
    0x75, 0x70, 0x6c, 0x1b, 0x11, 0x25, 0x25, 0x70, 0x7f, 0x7e, 0x67, 0x63, 0x30, 0x3c, 0x6d, 0x6a,
    0x01, 0x51, 0x59, 0x5f, 0x56, 0x13, 0x10, 0x43, 0x19, 0x18, 0xe5, 0xe0, 0xbe, 0xbf, 0xbd, 0xe9,
    0xf0, 0xf1, 0xf9, 0xfa, 0xab, 0x8f, 0xc1, 0xdf, 0xcf, 0x8d, 0xf8, 0xe7, 0xe2, 0xe9, 0x93, 0x8e,
    0xec, 0xf5, 0xc8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   
    0x37, 0x7a, 0x07, 0x11, 0x1f, 0x1d, 0x68, 0x25, 0x32, 0x77, 0x1e, 0x62, 0x23, 0x5b, 0x47, 0x55,
    0x53, 0x30, 0x11, 0x42, 0xf6, 0xf1, 0xb1, 0xe6, 0xc3, 0xcc, 0xf8, 0xc5, 0xe4, 0xcc, 0xc0, 0xd3,
    0x85, 0xfd, 0x9a, 0xe3, 0xe6, 0x81, 0xb5, 0xbb, 0xd7, 0xcd, 0x87, 0xa3, 0xd3, 0x6b, 0x36, 0x6f,
    0x6f, 0x66, 0x55, 0x30, 0x16, 0x45, 0x5e, 0x09, 0x74, 0x5c, 0x3f, 0x29, 0x2b, 0x66, 0x3d, 0x0d,
    0x02, 0x30, 0x28, 0x35, 0x15, 0x09, 0x15, 0xdd, 0xec, 0xb8, 0xe2, 0xfb, 0xd8, 0xcb, 0xd8, 0xd1,
    0x8b, 0xd5, 0x82, 0xd9, 0x9a, 0xf1, 0x92, 0xab, 0xe8, 0xa6, 0xd6, 0xd0, 0x8c, 0xaa, 0xd2, 0x94,
    0xcf, 0x45, 0x46, 0x67, 0x20, 0x7d, 0x44, 0x14, 0x6b, 0x45, 0x6d, 0x54, 0x03, 0x17, 0x60, 0x62,
    0x55, 0x5a, 0x4a, 0x66, 0x61, 0x11, 0x57, 0x68, 0x75, 0x05, 0x62, 0x36, 0x7d, 0x02, 0x10, 0x4b,
    0x08, 0x22, 0x42, 0x32, 0xba, 0xe2, 0xb9, 0xe2, 0xd6, 0xb9, 0xff, 0xc3, 0xe9, 0x8a, 0x8f, 0xc1,
    0x8f, 0xe1, 0xb8, 0xa4, 0x96, 0xf1, 0x8f, 0x81, 0xb1, 0x8d, 0x89, 0xcc, 0xd4, 0x78, 0x76, 0x61,
    0x72, 0x3e, 0x37, 0x23, 0x56, 0x73, 0x71, 0x79, 0x63, 0x7c, 0x08, 0x11, 0x20, 0x69, 0x7a, 0x14,
    0x68, 0x05, 0x21, 0x1e, 0x32, 0x27, 0x59, 0xb7, 0xcf, 0xab, 0xdd, 0xd5, 0xcc, 0x97, 0x93, 0xf2,
    0xe7, 0xc0, 0xeb, 0xff, 0xe9, 0xa3, 0xbf, 0xa1, 0xab, 0x8b, 0xbb, 0x9e, 0x9e, 0x8c, 0xa0, 0xc1,
    0x9b, 0x5a, 0x2f, 0x2f, 0x4e, 0x4e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
  ],
 
  exec: function()
  {
    // virtual machine architecture
    // ++++++++++++++++++++++++++++
    //
    // segmented memory model with 16-byte segment size (notation seg:offset)
    //
    // 4 general-purpose registers (r0-r3)
    // 2 segment registers (cs, ds equiv. to r4, r5)
    // 1 flags register (fl)
    //
    // instruction encoding
    // ++++++++++++++++++++
    //
    //           byte 1               byte 2 (optional)
    // bits      [ 7 6 5 4 3 2 1 0 ]  [ 7 6 5 4 3 2 1 0 ]
    // opcode      - - -             
    // mod               -           
    // operand1            - - - -
    // operand2                         - - - - - - - -
    //
    // operand1 is always a register index
    // operand2 is optional, depending upon the instruction set specified below
    // the value of mod alters the meaning of any operand2
    //   0: operand2 = reg ix
    //   1: operand2 = fixed immediate value or target segment (depending on instruction)
    //
    // instruction set
    // +++++++++++++++
    //
    // Notes:
    //   * r1, r2 => operand 1 is register 1, operand 2 is register 2
    //   * movr r1, r2 => move contents of register r2 into register r1
    //
    // opcode | instruction | operands (mod 0) | operands (mod 1)
    // -------+-------------+------------------+-----------------
    // 0x00   | jmp         | r1               | r2:r1
    // 0x01   | movr        | r1, r2           | rx,   imm
    // 0x02   | movm        | r1, [ds:r2]      | [ds:r1], r2
    // 0x03   | add         | r1, r2           | r1,   imm
    // 0x04   | xor         | r1, r2           | r1,   imm
    // 0x05   | cmp         | r1, r2           | r1,   imm
    // 0x06   | jmpe        | r1               | r2:r1
    // 0x07   | hlt         | N/A              | N/A
    //
    // flags
    // +++++
    //
    // cmp r1, r2 instruction results in:
    //   r1 == r2 => fl = 0
    //   r1 < r2  => fl = 0xff
    //   r1 > r2  => fl = 1
    //
    // jmpe r1
    //   => if (fl == 0) jmp r1
    //      else nop
   
    throw "VM.exec not yet implemented";
  }
 
};

//--------------------------------------------------------------------------------------------------

try
{
  VM.exec();
}
catch(e)
{
  alert('\nError: ' + e + '\n');
}

//--------------------------------------------------------------------------------------------------
alibaba42
New User
New User
 
Posts: 3
Joined: Wed Nov 30, 2011 1:02 pm
Blog: View Blog (0)


Re: can anyone understand this?

Post by LoGiCaL__ on Fri Dec 02, 2011 1:33 pm
([msg=63154]see Re: can anyone understand this?[/msg])

I've placed your code inside code tags to make it more legible.
User avatar
LoGiCaL__
Addict
Addict
 
Posts: 1060
Joined: Sun May 30, 2010 12:33 pm
Blog: View Blog (0)


Re: can anyone understand this?

Post by tremor77 on Fri Dec 02, 2011 4:14 pm
([msg=63161]see Re: can anyone understand this?[/msg])

LOL - so you are trying to apply for a job with England's Cyber Security Firm? This is phase 2 of the stego challenge of Canyoucrackit.co.uk

Basically using that code you have to put together a virtual PC environment. It's using Googles V8 javascript engine. After that you do some other thing or whatever.. I haven't had the time to investigate enough myself. Anyway...

you started with this right:

Image



Not to be a spoiler but the answer is "Drink more Ovaltine".
Image
User avatar
tremor77
Contributor
Contributor
 
Posts: 862
Joined: Wed Mar 31, 2010 12:00 pm
Location: New York
Blog: View Blog (0)


Re: can anyone understand this?

Post by tgoe on Fri Dec 02, 2011 10:16 pm
([msg=63169]see Re: can anyone understand this?[/msg])

lmao, just in time for x-mas!

http://www.youtube.com/watch?v=zdA__2tKoIU
User avatar
tgoe
Contributor
Contributor
 
Posts: 633
Joined: Sun Sep 28, 2008 2:33 pm
Location: q3dm7
Blog: View Blog (0)


Re: can anyone understand this?

Post by LoGiCaL__ on Sat Dec 03, 2011 4:44 pm
([msg=63172]see Re: can anyone understand this?[/msg])

User avatar
LoGiCaL__
Addict
Addict
 
Posts: 1060
Joined: Sun May 30, 2010 12:33 pm
Blog: View Blog (0)


Re: can anyone understand this?

Post by tremor77 on Mon Dec 05, 2011 10:22 pm
([msg=63208]see Re: can anyone understand this?[/msg])

oh ffs r u serious, why didn't i think of that? Literally wasted 2 whole minutes check that thing out.... no wonder these tools can't get anyone hired... .htaccess GHCQ? eva' heard of it?
Image
User avatar
tremor77
Contributor
Contributor
 
Posts: 862
Joined: Wed Mar 31, 2010 12:00 pm
Location: New York
Blog: View Blog (0)


Re: can anyone understand this?

Post by centip3de on Wed Dec 07, 2011 11:47 pm
([msg=63243]see Re: can anyone understand this?[/msg])

alibaba42 wrote:hi guys, was wondering if anyone understands this javascript:

Code: Select all
//--------------------------------------------------------------------------------------------------
//
// stage 2 of 3
//
// challenge:
//   reveal the solution within VM.mem
//
// disclaimer:
//   tested in ie 9, firefox 6, chrome 14 and v8 shell (http://code.google.com/apis/v8/build.html),
//   other javascript implementations may or may not work.
//
//--------------------------------------------------------------------------------------------------

var VM = {
 
  cpu: {
    ip: 0x00,
   
    r0: 0x00,
    r1: 0x00,
    r2: 0x00,
    r3: 0x00,
   
    cs: 0x00,
    ds: 0x10,
   
    fl: 0x00,
   
    firmware: [0xd2ab1f05, 0xda13f110]
  },
 
  mem: [
    0x31, 0x04, 0x33, 0xaa, 0x40, 0x02, 0x80, 0x03, 0x52, 0x00, 0x72, 0x01, 0x73, 0x01, 0xb2, 0x50,
    0x30, 0x14, 0xc0, 0x01, 0x80, 0x00, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   
    0x98, 0xab, 0xd9, 0xa1, 0x9f, 0xa7, 0x83, 0x83, 0xf2, 0xb1, 0x34, 0xb6, 0xe4, 0xb7, 0xca, 0xb8,
    0xc9, 0xb8, 0x0e, 0xbd, 0x7d, 0x0f, 0xc0, 0xf1, 0xd9, 0x03, 0xc5, 0x3a, 0xc6, 0xc7, 0xc8, 0xc9,
    0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9,
    0xda, 0xdb, 0xa9, 0xcd, 0xdf, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
    0x26, 0xeb, 0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9,
    0x7d, 0x1f, 0x15, 0x60, 0x4d, 0x4d, 0x52, 0x7d, 0x0e, 0x27, 0x6d, 0x10, 0x6d, 0x5a, 0x06, 0x56,
    0x47, 0x14, 0x42, 0x0e, 0xb6, 0xb2, 0xb2, 0xe6, 0xeb, 0xb4, 0x83, 0x8e, 0xd7, 0xe5, 0xd4, 0xd9,
    0xc3, 0xf0, 0x80, 0x95, 0xf1, 0x82, 0x82, 0x9a, 0xbd, 0x95, 0xa4, 0x8d, 0x9a, 0x2b, 0x30, 0x69,
    0x4a, 0x69, 0x65, 0x55, 0x1c, 0x7b, 0x69, 0x1c, 0x6e, 0x04, 0x74, 0x35, 0x21, 0x26, 0x2f, 0x60,
    0x03, 0x4e, 0x37, 0x1e, 0x33, 0x54, 0x39, 0xe6, 0xba, 0xb4, 0xa2, 0xad, 0xa4, 0xc5, 0x95, 0xc8,
    0xc1, 0xe4, 0x8a, 0xec, 0xe7, 0x92, 0x8b, 0xe8, 0x81, 0xf0, 0xad, 0x98, 0xa4, 0xd0, 0xc0, 0x8d,
    0xac, 0x22, 0x52, 0x65, 0x7e, 0x27, 0x2b, 0x5a, 0x12, 0x61, 0x0a, 0x01, 0x7a, 0x6b, 0x1d, 0x67,
    0x75, 0x70, 0x6c, 0x1b, 0x11, 0x25, 0x25, 0x70, 0x7f, 0x7e, 0x67, 0x63, 0x30, 0x3c, 0x6d, 0x6a,
    0x01, 0x51, 0x59, 0x5f, 0x56, 0x13, 0x10, 0x43, 0x19, 0x18, 0xe5, 0xe0, 0xbe, 0xbf, 0xbd, 0xe9,
    0xf0, 0xf1, 0xf9, 0xfa, 0xab, 0x8f, 0xc1, 0xdf, 0xcf, 0x8d, 0xf8, 0xe7, 0xe2, 0xe9, 0x93, 0x8e,
    0xec, 0xf5, 0xc8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   
    0x37, 0x7a, 0x07, 0x11, 0x1f, 0x1d, 0x68, 0x25, 0x32, 0x77, 0x1e, 0x62, 0x23, 0x5b, 0x47, 0x55,
    0x53, 0x30, 0x11, 0x42, 0xf6, 0xf1, 0xb1, 0xe6, 0xc3, 0xcc, 0xf8, 0xc5, 0xe4, 0xcc, 0xc0, 0xd3,
    0x85, 0xfd, 0x9a, 0xe3, 0xe6, 0x81, 0xb5, 0xbb, 0xd7, 0xcd, 0x87, 0xa3, 0xd3, 0x6b, 0x36, 0x6f,
    0x6f, 0x66, 0x55, 0x30, 0x16, 0x45, 0x5e, 0x09, 0x74, 0x5c, 0x3f, 0x29, 0x2b, 0x66, 0x3d, 0x0d,
    0x02, 0x30, 0x28, 0x35, 0x15, 0x09, 0x15, 0xdd, 0xec, 0xb8, 0xe2, 0xfb, 0xd8, 0xcb, 0xd8, 0xd1,
    0x8b, 0xd5, 0x82, 0xd9, 0x9a, 0xf1, 0x92, 0xab, 0xe8, 0xa6, 0xd6, 0xd0, 0x8c, 0xaa, 0xd2, 0x94,
    0xcf, 0x45, 0x46, 0x67, 0x20, 0x7d, 0x44, 0x14, 0x6b, 0x45, 0x6d, 0x54, 0x03, 0x17, 0x60, 0x62,
    0x55, 0x5a, 0x4a, 0x66, 0x61, 0x11, 0x57, 0x68, 0x75, 0x05, 0x62, 0x36, 0x7d, 0x02, 0x10, 0x4b,
    0x08, 0x22, 0x42, 0x32, 0xba, 0xe2, 0xb9, 0xe2, 0xd6, 0xb9, 0xff, 0xc3, 0xe9, 0x8a, 0x8f, 0xc1,
    0x8f, 0xe1, 0xb8, 0xa4, 0x96, 0xf1, 0x8f, 0x81, 0xb1, 0x8d, 0x89, 0xcc, 0xd4, 0x78, 0x76, 0x61,
    0x72, 0x3e, 0x37, 0x23, 0x56, 0x73, 0x71, 0x79, 0x63, 0x7c, 0x08, 0x11, 0x20, 0x69, 0x7a, 0x14,
    0x68, 0x05, 0x21, 0x1e, 0x32, 0x27, 0x59, 0xb7, 0xcf, 0xab, 0xdd, 0xd5, 0xcc, 0x97, 0x93, 0xf2,
    0xe7, 0xc0, 0xeb, 0xff, 0xe9, 0xa3, 0xbf, 0xa1, 0xab, 0x8b, 0xbb, 0x9e, 0x9e, 0x8c, 0xa0, 0xc1,
    0x9b, 0x5a, 0x2f, 0x2f, 0x4e, 0x4e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
  ],
 
  exec: function()
  {
    // virtual machine architecture
    // ++++++++++++++++++++++++++++
    //
    // segmented memory model with 16-byte segment size (notation seg:offset)
    //
    // 4 general-purpose registers (r0-r3)
    // 2 segment registers (cs, ds equiv. to r4, r5)
    // 1 flags register (fl)
    //
    // instruction encoding
    // ++++++++++++++++++++
    //
    //           byte 1               byte 2 (optional)
    // bits      [ 7 6 5 4 3 2 1 0 ]  [ 7 6 5 4 3 2 1 0 ]
    // opcode      - - -             
    // mod               -           
    // operand1            - - - -
    // operand2                         - - - - - - - -
    //
    // operand1 is always a register index
    // operand2 is optional, depending upon the instruction set specified below
    // the value of mod alters the meaning of any operand2
    //   0: operand2 = reg ix
    //   1: operand2 = fixed immediate value or target segment (depending on instruction)
    //
    // instruction set
    // +++++++++++++++
    //
    // Notes:
    //   * r1, r2 => operand 1 is register 1, operand 2 is register 2
    //   * movr r1, r2 => move contents of register r2 into register r1
    //
    // opcode | instruction | operands (mod 0) | operands (mod 1)
    // -------+-------------+------------------+-----------------
    // 0x00   | jmp         | r1               | r2:r1
    // 0x01   | movr        | r1, r2           | rx,   imm
    // 0x02   | movm        | r1, [ds:r2]      | [ds:r1], r2
    // 0x03   | add         | r1, r2           | r1,   imm
    // 0x04   | xor         | r1, r2           | r1,   imm
    // 0x05   | cmp         | r1, r2           | r1,   imm
    // 0x06   | jmpe        | r1               | r2:r1
    // 0x07   | hlt         | N/A              | N/A
    //
    // flags
    // +++++
    //
    // cmp r1, r2 instruction results in:
    //   r1 == r2 => fl = 0
    //   r1 < r2  => fl = 0xff
    //   r1 > r2  => fl = 1
    //
    // jmpe r1
    //   => if (fl == 0) jmp r1
    //      else nop
   
    throw "VM.exec not yet implemented";
  }
 
};

//--------------------------------------------------------------------------------------------------

try
{
  VM.exec();
}
catch(e)
{
  alert('\nError: ' + e + '\n');
}

//--------------------------------------------------------------------------------------------------


That just looks like an Java based 8-bit VM...
Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning. -Rick Cook
User avatar
centip3de
Moderator
Moderator
 
Posts: 1412
Joined: Fri Aug 20, 2010 5:46 pm
Blog: View Blog (0)



Return to Programming

Who is online

Users browsing this forum: No registered users and 0 guests