crc32.h

CRC32算法, 可以对字符串或文件进行CRC32计算, 带进度条.内含VC++6.0源码

//	   D[5] ^ D[4] ^ D[3] ^ D[2] ^ C[2] ^ C[3] ^ C[4] ^ C[5] ^
//	   C[6] ^ C[7] ^ C[10] ^ C[14] ^ C[15] ^ C[16] ^ C[19] ^
//	   C[21] ^ C[23] ^ C[24] ^ C[25] ^ C[26] ^ C[28] ^ C[29];
//	   NewCRC[31] = D[30] ^ D[29] ^ D[27] ^ D[26] ^ D[25] ^ D[24] ^
//	   D[22] ^
//	   D[20] ^ D[17] ^ D[16] ^ D[15] ^ D[11] ^ D[8] ^ D[7] ^
//	   D[6] ^ D[5] ^ D[4] ^ D[3] ^ C[3] ^ C[4] ^ C[5] ^ C[6] ^
//	   C[7] ^ C[8] ^ C[11] ^ C[15] ^ C[16] ^ C[17] ^ C[20] ^
//	   C[22] ^ C[24] ^ C[25] ^ C[26] ^ C[27] ^ C[29] ^ C[30];
//	   nextCRC32_D32 = NewCRC;
//	   end
//	   endfunction
//
//	8.3 Some Hardware Implementation Comments
//
//	   The iSCSI spec specifies that the most significant 32 bits of the
//	   data be complemented prior to performing the CRC computation.  For
//	   most implementations of the CRC algorithm, such as the ones described
//	   here, which perform simultaneous multiplication by x^32 and division
//	   by the CRC polynomial, this is equivalent to initializing the CRC
//	   register to ones regardless of the CRC polynomial.  For other
//	   implementations, in particular one that only performs division by the
//	   CRC polynomial (and for which the prescribed multiplication by x^32
//	   is performed externally) initializing the CRC register to ones does
//	   not have the same effect as complementing the most significant 32
//	   bits of the message.  With such implementations, for the CRC32c
//	   polynomial, initializing the CRC register to 0x2a26f826 has the same
//	   effect as complementing the most significant 32 bits of the data.
//	   See reference [Tuikov&Cavanna] for more details.
//
//	8.4 Fast Hardware Implementation References
//
//	   Fast hardware implementations start from a canonic scheme (as the one
//	   presented in 7.2) and optimize it based on different criteria.  Two
//	   classic papers on this subject are [Albertengo1990] and [Glaise1997].
//	   A more modern (and systematic) approach can be found in [Shie2001]
//	   and [Sprachman2001].
//
//	9. Summary and Conclusions
//
//	   The following table is a summary of the error detection capabilities
//	   of the different codes analyzed.  In the table, d is the minimal
//	   distance at block length block (in bits), i/byte - software
//	   instructions/byte, Table size (if table lookup needed), T-look number
//	   of lookups/byte, Pudb - Pud burst and Puds - Pud sporadic:
//
//
//
//
//
//	Sheinwald, et. al.           Informational                     [Page 18]
//	
//	RFC 3385                iSCSI CRC Considerations          September 2002
//
//
//	   +-----------------------------------------------------------+
//	   | Code      |d| Block |i/Byte|Tsize|T-look| Pudb   | Puds   |
//	   +-----------------------------------------------------------+
//	   | Fletcher32|3| 2^19  | 2    |  -  | -    | 10^-37 | 10^-36 |
//	   +-----------------------------------------------------------+
//	   | Adler32   |3| 2^19  | 3    |  -  | -    | 10^-36 | 10^-35 |
//	   +-----------------------------------------------------------+
//	   | IEEE-802  |3| 2^16  | 2.75 | 2^18| 0.5/b| 10^-41 | 10^-40 |
//	   +-----------------------------------------------------------+
//	   | CRC32C    |3| 2^31-1| 2.75 | 2^18| 0.5/b| 10^-41 | 10^-40 |
//	   +-----------------------------------------------------------+
//
//	   The probabilities for undetected errors in the above table are
//	   computed assuming uniformly distributed data.  For real data - that
//	   can be biased - [Stone98], checksums behave substantially worse than
//	   CRCs.
//
//	   Considering the protection level it offers, the lack of sensitivity
//	   for biased data and the large block it can protect, we think that
//	   CRC32C is a good choice as a basic error detection mechanism for
//	   iSCSI.
//
//	   Please observe also that burst errors characterized by a fixed
//	   average time will have a higher impact on error detection capability
//	   as the speed of the channels (machines and networks) increases.  The
//	   only way to keep the Pud within bounds for the long-term is to reduce
//	   the BER by using better coding of lower levels of the channel.
//
//	10. Security Considerations
//
//	   These codes detect unintentional changes to data such as those caused
//	   by noise. In an environment where an attacker can change the data, it
//	   can also change the error-detection code to match the new data.
//	   Therefore, the error-detection codes overviewed here do not provide
//	   protection against attacks.  Indeed, these codes are not intended for
//	   security purposes; they are meant to be used within some application,
//	   and the application's threat model and security design control the
//	   security considerations for the use of the CRC.
//
//	11. References and Bibliography
//
//	   [Albertengo1990] G. Albertengo, R. Sisto, "Parallel CRC Generation
//						IEEE Micro", Vol. 10, No. 5, October 1990, pp. 63-
//						71.
//
//	   [Arazi]          B Arazi, "A commonsense Approach to the Theory of
//						Error Correcting codes".
//
//
//
//
//	Sheinwald, et. al.           Informational                     [Page 19]
//	
//	RFC 3385                iSCSI CRC Considerations          September 2002
//
//
//	   [Baicheva]       T Baicheva, S Dodunekov and P Kazakov, "Undetected
//						error probability performance of cyclic redundancy-
//						check codes of 16-bit redundancy", IEEE Proceedings
//						on Communications, 147:253-256, October 2000.
//
//	   [Black]          "Fast CRC32 in Software"  by Richard Black, 1994, at
//						www.cl.cam.ac.uk/Research/SRG/bluebook/21/crc/crc.
//						html.
//
//	   [Castagnoli93]   Guy Castagnoli, Stefan Braeuer and Martin Herrman
//						"Optimization of Cyclic Redundancy-Check Codes with
//						24 and 32 Parity Bits", IEEE Transact. on
//						Communications, Vol. 41, No. 6, June 1993.
//
//	   [braun01]        Florian Braun and Marcel Waldvogel, "Fast
//						Incremental CRC Updates for IP over ATM Networks",
//						IEEE, High Performance Switching and Routing, 2001,
//						pp. 48-52.
//
//	   [FITS]           "NASA FITS documents" at http://heasarc.gsfc.nasa.
//						gov/docs/heasarc/ofwg/docs/general/checksum/node26.
//						html.
//
//	   [Fujiwara89]     Toru Fujiwara, Tadao Kasami, and Shu Lin, "Error
//						detecting capabilities of the shortened hamming
//						codes adopted forerror detection in IEEE standard
//						802.3", IEEE Transactions on Communications, COM-
//						37:986989, September 1989.
//
//	   [Glaise1997]     Glaise, R. J., "A two-step computation of cyclic
//						redundancy code CRC-32 for ATM networks", IBM
//						Journal of Research and Development, Volume 41,
//						Number 6, 1997.
//
//	   [ieee1364]       IEEE Standard Hardware Description Language Based on
//						the Verilog Hardware Description Language, IEEE
//						Standard 1364-1995, December 1995.
//
//	   [LinCostello]    S. Lin and D.J. Costello, Jr., "Error Control
//						Coding: Fundamentals and Applications", Englewood
//						Cliffs, NJ: Prentice Hall, 1983.
//
//	   [Peterson]       W Wesley Peterson & E J Weldon - Error Correcting
//						Codes - First Edition 1961/Second Edition 1972.
//
//
//
//
//
//
//
//	Sheinwald, et. al.           Informational                     [Page 20]
//	
//	RFC 3385                iSCSI CRC Considerations          September 2002
//
//
//	   [RFC2026]        Bradner, S., "The Internet Standards Process --
//						Revision 3", BCP 9, RFC 2026, October 1996.
//
//	   [Ritter]         Ritter, T. 1986. The Great CRC Mystery. Dr. Dobb's
//						Journal of Software Tools. February. 11(2): 26-34,
//						76-83.
//
//	   [Polynomials]    "Information on Primitive and Irreducible
//						Polynomials" at http://www.theory.csc.uvic.ca/~cos/
//						inf/neck/PolyInfo.html.
//
//	   [RFC1146]        Zweig, J. and C. Partridge, "TCP Alternate Checksum
//						Options", RFC 1146, March 1990.
//
//	   [RFC1950]        Deutsch, P. and J. Gailly, "ZLIB Compressed Data
//						Format Specification version 3.3", RFC 1950, May
//						1996.
//
//	   [Shie2001]       Ming-Der Shieh, et. al, "A Systematic Approach for
//						Parallel CRC Computations", Journal of Information
//						Science and Engineering, Vol.17 No.3, pp.445-461.
//
//	   [Sprachman2001]  Michael Sprachman, "Automatic Generation of Parallel
//						CRC Circuits", IEEE Design & Test May-June 2001.
//
//	   [Stone98]        J. Stone et. al., "Performance of Checksums and
//						CRC's over Real Data", IEEE/ACM Transactions on
//						Networking, Vol. 6, No. 5, October 1998.
//
//	   [Williams]       Ross Williams - A PAINLESS GUIDE TO CRC ERROR
//						DETECTION ALGORITHMS widely available on the net -
//						(e.g., ftp.adelaide.edu.au/pub/rocksoft/crc_v3.txt)
//
//	   [Wolf82]         J.K. Wolf, Arnold Michelson and Allen Levesque, "On
//						the probability of undetected error for linear block
//						codes", IEEE Transactions on Communications, COM-30:
//						317-324, 1982.
//
//	   [Wolf88]         J.K. Wolf, R.D. Blackeney, "An Exact Evaluation of
//						the Probability of Undetected Error for Certain
//						Shortened Binary CRC Codes", Proc. MILCOM - IEEE
//						1988.
//
//	   [Wolf94J]        J.K. Wolf and Dexter Chun, "The single burst error
//						detection performance of binary cyclic codes", IEEE
//						Transactions on Communications COM-42:11-13, January
//						1994.
//
//
//
//
//	Sheinwald, et. al.           Informational                     [Page 21]
//	
//	RFC 3385                iSCSI CRC Considerations          September 2002
//
//
//	   [Wolf94O]        Dexter Chun and J.K. Wolf, "Special Hardware for
//						computing the probability of undetected error for
//						certain binary crc codes and test results", IEEE
//						Transactions on Communications, COM-42:2769-2772.
//
//	   [Tuikov&Cavanna] Luben Tuikov and Vicente Cavanna, "The iSCSI CRC32C
//						Digest and the Simultaneous Multiply and Divide
//						Algorithm", January 30, 2002. White paper
//						distributed to the IETF ips iSCSI reflector.
//
//	12. Acknowledgements
//
//	   We would like to thank Matt Wakeley for providing us with the
//	   motivation to co-author this paper and for helpful discussions on the
//	   subject matter, during his employment with Agilent.
//
//	13. Authors' Addresses
//
//	   Julian Satran
//	   IBM, Haifa Research Lab
//	   MATAM - Advanced Technology Center
//	   Haifa 31905, Israel
//	   EMail: [e-mail]
//
//
//	   Dafna Sheinwald
//	   IBM, Haifa Research Lab
//	   MATAM - Advanced Technology Center
//	   Haifa 31905, Israel
//	   EMail: [e-mail]
//
//
//	   Pat Thaler
//	   Agilent Technologies
//	   1101 Creekside Ridge Drive
//	   Suite 100, M/S RH21
//	   Roseville, CA 95661
//	   EMail: [e-mail]
//
//
//	   Vicente Cavanna
//	   Agilent Technologies
//	   1101 Creekside Ridge Drive
//	   Suite 100, M/S RH21
//	   Roseville, CA 95661
//	   EMail: [e-mail]
//
//
//
//
//
//	Sheinwald, et. al.           Informational                     [Page 22]
//	
//	RFC 3385                iSCSI CRC Considerations          September 2002
//
//
//	14.  Full Copyright Statement
//
//	   Copyright (C) The Internet Society (2002).  All Rights Reserved.
//
//	   This document and translations of it may be copied and furnished to
//	   others, and derivative works that comment on or otherwise explain it
//	   or assist in its implementation may be prepared, copied, published
//	   and distributed, in whole or in part, without restriction of any
//	   kind, provided that the above copyright notice and this paragraph are
//	   included on all such copies and derivative works.  However, this
//	   document itself may not be modified in any way, such as by removing
//	   the copyright notice or references to the Internet Society or other
//	   Internet organizations, except as needed for the purpose of
//	   developing Internet standards in which case the procedures for
//	   copyrights defined in the Internet Standards process must be
//	   followed, or as required to translate it into languages other than
//	   English.
//
//	   The limited permissions granted above are perpetual and will not be
//	   revoked by the Internet Society or its successors or assigns.
//
//	   This document and the information contained herein is provided on an
//	   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
//	   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
//	   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
//	   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
//	   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
//
//	Acknowledgement
//
//	   Funding for the RFC Editor function is currently provided by the
//	   Internet Society.
//
//
//
//
//
//
//
//
//
//
//
//
//
//
//
//
//
//
//
//	Sheinwald, et. al.           Informational                     [Page 23]
//