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The MaybeBoost Hash Library: Quickstart

Want to get started without worry about the details? Here's how.

1. Include the boost/hash.hpp header. No linking is required.
2. Choose the hash algorithm you with to use. The following are provided:
   

   Name	Digest Bits	HashAlgorithm Model (in boost::hash)	Reference	Design Type	Notes
   Adler-h (h in {8, 16, 24, ..., 64})	h	adler<h>	RFC 1950	Checksum	Only supports octets as input values
   CRC-32/PNG	32	crc32_png	PNG Specification, Section 3.4	Checksum	Also used by cksfv; Only supports bytes as input values
   CubeHash-h (h in {8, 16, 24, ..., 512})	h	cubehash<h>	CubeHash NIST Submission	Cryptographic	SHA-3 candidate; Not yet mature.
   MD4	128	md4	RFC 1320	Cryptographic	Practical attacks exist
   MD5	128	md5	RFC 1321
   SHA	160	sha	FIPS 180	Cryptographic	Collisions known; Repealed
   SHA-1	160	sha1	FIPS 180-3		Some concern
   SHA-224	224	sha2<224>			As of 2010, considered secure by NIST
   SHA-256	256	sha2<256>
   SHA-384	384	sha2<384>
   SHA-512	512	sha2<512>

   If you need security against a malicious adversary, sha2<h> is, as of 2010, the recommended choice. If not, then two popular choices are crc<h> for checksums and md5 for fingerprinting.
3. With the chosen HashAlgorithm, call the boost::hash::compute_digest<HashAlgorithm> function, passing it an input range (such as a container). That will return the digest as an object of type HashAlgorithm::digest_type.
4. The resulting digest may then be output to a std::ostream or compared against other message digests (such as one read from a std::istream).

Here's a sample complete program, example/quickstart.cpp:

#include <boost/hash.hpp>

#include <iostream>
#include <string>

int main() {
    std::string s = "Hello World!";
}

int main() {
    using namespace boost::hash;
    std::string s = "Hello World!";
    typedef boost::hash::sha2<256> HashAlgorithm;
    HashAlgorithm::digest_type digest = compute_digest<HashAlgorithm>(s);
    std::cout << digest << "\n";
}

The distribution also includes a "hash this file" example, example/hashsum.cpp, along the lines of the coreutils md5sum and sha1sum programs.

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