Subversion Repositories cryptopan_core

Crypto-PAn core

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http://www.opencores.org/projects.cgi/web/cryptopan_core/

1. Introduction

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  This project is a hardware implementation of the Crypto-PAn technique for

  cryptography based prefix preserving anonymization of IP addresses, described in

  [1]. A highly pipelined implementation of the AES cipher (Rijndael) [2] is used

  as the underlying pseudorandom function.

  For every bit of the input IP address, a 128-bit AES block encrypt is

  required. To be capable of high line rates, a fully pipelined AES engine

  capable of 32Gbit/s throughput on a Xilinx Virtex-4 FPGA was implemented.

  The AES engine has a few options for the implementation of the S-boxes, which

  affects area and timing performance. It is possible to use a logic

  implementation by setting the 'use_bram' constant in 'cryptopan_package' to

  'false' and 'syn_romstyle' attribute in 'sbox' to 'logic'. If 'syn_romstyle'

  isn't set then block rams may be inferred. Alternatively, if

  block rams are present, as in the Xilinx Virtex FPGA's, eight dual port

  18Kbit B-RAMs may be used as ROM's by setting 'use_bram' to 'true'.

2. Simulation/Synthesis results

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  This core has been simulated using Aldec Riviera 200602, using a compiled

  version of the XilinxCoreLib from Xilinx ISE 8.2.

  Synthesis for the Virtex-4 FX60 FPGA was carried out using Synplicity Synplify

  Pro, and Xilinx ISE 8.2 for map, floorplanning, and place & route. To meet

  timing at 250MHz floorplanning constraints were required. The constraints

  used for the FX60 part are included in the synth directory as an example.

3. Files

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  README                     This file.

  COPYING                    GNU General public license.

  rtl/cryptopan_package.vhd  A package which provides some global functions,

                             types and constants.

  rtl/mixcolumns.vhd         Performs the 'Mix Columns' step of the Rijndael

                             cipher.

  rtl/subbytesshiftrows.vhd  Performs the 'Sub bytes' and 'Shift rows' steps of

                             the Rijndael cipher.

  rtl/round_unit.vhd         Implements the transformations for a whole round

                             of the Rijndael cipher.

  rtl/sbox.vhd               The Rijndael S-box.

  rtl/aes_encrypt_unit.vhd   A fully pipelined implementation of AES, using

                             128-bit keys and blocks. Supports online loading

                             of keys.

  rtl/cryptopan_unit.vhd     Uses aes_encrypt_unit to perform the Crypto-PAn

                             technique on IP adresses.

  rtl/sbox.coe               Coefficiants file for S-Box ROM.

  rtl/dual_bram_256x8.vhd    Memory init file for dual block ram as in Virtex

                             FPGAs.

  tb/sbsr_tb.vhd             Testbench for the subbytesshiftrows unit.

  tb/cryptopan_unit_tb.vhd   Testbench for the cryptopan_unit.

  tb/aes_encrypt_unit_tb.vhd Testbench for the aes_encrypt_unit.

  synth/virtex4_area         Area usage information for the Xilinx V4 FX60.

  synth/virtex4_timing       Timing report for the Xilinx V4 FX60.

  synth/cryptopan_unit.ucf   Timing and floorplan constraints Xilinx V4 FX60 to

                             run at 250MHz. This gives the AES engine a

                             throughput of 32Gbit/s.

  sim/sample_trace_raw       Test vectors from C++ implementation by Jinliang

                             Fan.

  sim/sample_trace_anon      Anonymized output from test vectors.

  sim/trace_raw_bin          Test vectors from C++ implementation by Jinliang

                             Fan in binary format for easy testbenching.

  sim/trace_anon_bin         Anonymized output from test vectors in binary

                             format for easy testbenching.

  sim/waveform.vcd           Waveform showing initialization and then

                             anonymization of a stream of IP addresses.

4. References

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  [1]   J. Fan, J. Xu, M. H. Ammar, S. B. Moon, "Prefix-preserving IP address

        anonymization: measurement-based security evaluation and a new

        cryptography-based scheme", Computer Networks, Volume 46, Issue 2, 7

        October 2004, Pages 253-272, Elsevier

  [2]   J.Daemen, V. Rijmen, "AES proposal: Rijndael", Technical report, Computer

        Security Resource Center, National Institute of Standards and

        Technology, February 2001

5. Contact

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  Please contact Anthony Blake (tonyb33@opencores.org) if you have any questions

  about the core. Your comments are highly appreciated.