| level01: e9gx26YEb2 | |
| $ cat > date << EOF | |
| #!/usr/bin/env python | |
| print open("/home/level02/.password").read() | |
| EOF | |
| $ chmod +x date | |
| $ export PATH=.:$PATH | |
| $ /levels/level01 |
| #!/usr/bin/python2.7 | |
| import os | |
| import re | |
| import sys | |
| import subprocess | |
| def usage(): | |
| print '''usage: %s pull <name> | push <dir>''' % sys.argv[0] | |
| sys.exit(1) |
Memory access has inconsistent costs currently. When decoding instructions it costs cycles, but things like [A] don't. For both a "real" DCPU and the emulator (assuming typical cache behavior), memory accesses are more expensive than register accesses.
| #!/usr/bin/env python3 | |
| import collections | |
| import os | |
| import re | |
| import sys | |
| import subprocess | |
| State = collections.namedtuple('State', 'num properties name sprite') | |
| Edge = collections.namedtuple('Edge', 'events begin end') |
| // Single-byte error correction for messages <255 bytes long | |
| // using two check bytes. Based on "CA-based byte error-correcting code" | |
| // by Chowdhury et al. | |
| // | |
| // rmmh 2013 | |
| // | |
| // This code is released into the public domain. | |
| uint8_t lfsr(uint8_t x) { | |
| return (x >> 1) ^ (-(x&1) & 0x8E); |
| DCPU-16 Hardware Info: | |
| Name: DPU16 -- DCPU Protection Unit (16-process version) | |
| ID: 0x1071c17b, version: 0x1000 | |
| Manufacturer: 0xcafe31aa | |
| Description: | |
| The DPU prevents unauthorized access to memory and hardware peripherals. | |
| Access permissions are determined by the process ID's bit being set in the | |
| corresponding mask. |
| /****************************** | |
| * Data Decompress Ver1.10 * | |
| * Programmed By Melody-Yoshi * | |
| ******************************/ | |
| /* How to use this function. | |
| void slidstart(unsigned char *,unsigned char *); | |
| first argument is top address of compress data.(align 4) | |
| next argument is top address of decompress. | |
| */ |
| [0-9a-zA-Z]{2} | |
| 30-39,41-5a,61-7a | |
| a:61 z:7a A:41 Z:5a 0:30 9:39 | |
| MSP430 alphanumeric shellcode is hard. There's no way to write to memory, | |
| no word-sized reg-reg operations, and all we have is add/sub/mov and a few conditional jumps. | |
| NanoCorruption: | |
| Goal: A fun-sized machine for more game-like hacking operations. | |
| The machine is a balanced ternary computer operating entirely on trytes. | |
| Trytes range in value from -364 to 364. | |
| A tryte is composed of 6 balanced ternary digits, called trits. | |
| Each trit has a value (-1 or T, 0, 1), meaning base conversions look like: |
| DCPU-16 Specification | |
| Copyright 2012 Mojang | |
| Version 1.1 (Check 0x10c.com for updated versions) | |
| * 16 bit words | |
| * 0x10000 words of ram | |
| * 8 registers (A, B, C, X, Y, Z, I, J) | |
| * program counter (PC) | |
| * stack pointer (SP) | |
| * extra/excess (EX) |