Free md5 hashing software for linux

fb_mhash is a UDF library for Firebird/Interbase. fb_mhash implements an interface to the mhash library (libmhash).
It support hash, hmac, and key generation algorithms, such as SHA1, MD5, MCRYPT, and S2K_SALTED.
Main features:
- support hash algorithms
- support hmac algorithms
- support key generator
Enhancements:
- Improved compatibility with Windows, and compiled versions of the library for Windows and Linux.

hash.c is a C hash table with quadratic probing. hash.c is very small and easy to use.
Compile: gcc -c hash.c
This hashtable uses C-strings for keys and quadratic probing instead of linked-list chains. It depends only on ANSI C and so should work anywhere.
API
hash * hash_new ( unsigned int size ) Create new hashtable.
void hash_destroy ( hash *h ) Free hashtable.
int hash_add ( hash *h , const char *key , void *value ) Add key/value pair.
void * hash_get ( hash *h , const char *key ) Return value matching given key.
void * hash_remove ( hash *h , const char *key ) Remove key from table, returing value.
unsigned int hash_size ( hash *h ) Returns total number of keys.
Enhancements:
- This release uses exponentiation instead of xor in hashing.
- It adds a hash_destroy function.

mod_vhost_hash_alias is an Apache HTTPD module that allows mass hosting with good distribution across a unified directory namespace.

Administrators no longer have to use complex regexps with mod_rewrite, since they can use mod_vhost_hash_alias to do a better job and use fewer resources.

mod_vhost_hash_alias is a component of the VHFFS hosting platform which is used by the Web hosting provider Tuxfamily.org.

Configuration

#
# Request the module
#
LoadModule vhost_hash_alias_module mod_vhost_hash_alias.so

#
# mod_vhost_hash_alias have to be enabled for each virtual host (catch-all)
#
HashEnable On

#
# Digest algorithm to use:
# CRC32, ADLER32, MD5, SHA1, SHA256, or other types
# supported by the module and libmhash
#
HashType md5

#
# The output encoding (rfc3548) of hash result
# hexa, base16_low, base16_up, base32_low, base32_up, base64_ufs,
#
HashEncoding base16

#
# Number of characters to use to build the document root
# The hash string is truncated to this length
#
HashLimit 8

#
# Splitting scheme
# Specify the size of each chunk of the digest string
# The last count is taken until the end of string is reached
#
HashSplit 1 1 3

#
# The base directory used to build the document root
# (mandatory)
#
HashDocumentRootPrefix /var/lib/www

#
# A directory added to the final built root
# (optionnal)
#
HashDocumentRootSuffix htdocs

#
# A list of host prefix to strip
# eg: this handle basic web aliasing
# http://www.example.com/
# will point on the same document root than
# http://example.com/
#
# (optionnal)
#
HashAddAliasPrefix www ftp

#
# A prefix to add to the server name before it will be hashed
# Act like a salt and must be keeped secret to be efficient
#
# (optionnal)
#

C Minimal Perfect Hashing Library encapsulates the newest and more efficient algorithms in an easy-to-use, production-quality, fast API. The library was designed to work with big entries that cannot fit in the main memory. It has been used successfully for constructing minimal perfect hash functions for sets with more than 100 million of keys, and we intend to expand this number to the order of billion of keys.
Main features:
- Fast.
- Space-efficient with main memory usage carefully documented.
- The best modern algorithms are available (or at least scheduled for implementation :-)).
- Works with in-disk key sets through of using the adapter pattern.
- Serialization of hash functions.
- Portable C code (currently works on GNU/Linux and WIN32 and is reported to work in OpenBSD and Solaris).
- Object oriented implementation.
- Easily extensible.
- Well encapsulated API aiming binary compatibility through releases.
- Free Software.
A perfect hash function maps a static set of n keys into a set of m integer numbers without collisions, where m is greater than or equal to n. If m is equal to n, the function is called minimal.
Minimal perfect hash functions are widely used for memory efficient storage and fast retrieval of items from static sets, such as words in natural languages, reserved words in programming languages or interactive systems, universal resource locations (URLs) in Web search engines, or item sets in data mining techniques. Therefore, there are applications for minimal perfect hash functions in information retrieval systems, database systems, language translation systems, electronic commerce systems, compilers, operating systems, among others.
The use of minimal perfect hash functions is, until now, restricted to scenarios where the set of keys being hashed is small, because of the limitations of current algorithms. But in many cases, to deal with huge set of keys is crucial. So, this project gives to the free software community an API that will work with sets in the order of billion of keys.
Probably, the most interesting application for minimal perfect hash functions is its use as an indexing structure for databases. The most popular data structure used as an indexing structure in databases is the B+ tree. In fact, the B+ tree is very used for dynamic applications with frequent insertions and deletions of records. However, for applications with sporadic modifications and a huge number of queries the B+ tree is not the best option, because practical deployments of this structure are extremely complex, and perform poorly with very large sets of keys such as those required for the new frontiers database applications.
For example, in the information retrieval field, the work with huge collections is a daily task. The simple assignment of ids to web pages of a collection can be a challenging task. While traditional databases simply cannot handle more traffic once the working set of web page urls does not fit in main memory anymore, minimal perfect hash functions can easily scale to hundred of millions of entries, using stock hardware.
As there are lots of applications for minimal perfect hash functions, it is important to implement memory and time efficient algorithms for constructing such functions. The lack of similar libraries in the free software world has been the main motivation to create the C Minimal Perfect Hashing Library (gperf is a bit different, since it was conceived to create very fast perfect hash functions for small sets of keys and CMPH Library was conceived to create minimal perfect hash functions for very large sets of keys). C Minimal Perfect Hashing Library is a portable LGPLed library to generate and to work with very efficient minimal perfect hash functions.
Enhancements:
- This release adds an implementation of a classical minimal perfect hash algorithm called fch.
- This is used as a basis for a new algorithm that can create minimal perfect hashes for billions of keys with less than four bits per key, and is ready to use.
- Suggestions and bugfixes from users have been incorporated.

fb_shash is a UDF library for Firebird/Interbase. It implements hash and hmac interfaces to the openssl library.

It supports hash and hmac algorithms such as SHA1 and MD5. fb_shash supports BLOB data.

Hash::NoVivify is a Perl extension for non-vivifying exists and defined functions.

SYNOPSIS

use Hash::NoVivify qw(Defined Exists);

...

if (Exists(%hash, qw(key1 key2 ... keyn ))) {
...
}

if (Defined(%hash, qw(key1 key2 ... keyn))) {
...
}

When used on a hash, the exists() and defined() functions will create entries in a hash in order to evaluate the function.

For instance, the code:

%a = (a => 1, b=> 2);
print "Doesnt existn" unless exists($a{c});
print "Also Doesnt existn" unless exists($a{c}->{d});
print "Oh, my, not goodn" if exists($a{c});

will print out:

Doesnt exist
Also Doesnt exist
Oh, my, not good

The Hash::NoVivify module provides two functions, Defined() and Exists(), which avoid this, at the cost of a slightly convoluted syntax. Both functions take a reference to a hash, followed by a list of descending keys defining the hash entry to be investigated.

mod_auth_token module uses token based authentication to secure downloads and prevent deep-linking.

Have your PHP script or servlet generate the to authenticate the download. Apache can then treat the download request like a normal file transfer without having to pipe the file through a script in order to add authentication.

You can find downloads, daily snapshots and support information at http://www.synd.info/

Usage:

The token is an hex-encoded MD5 hash of the secret password, relative file path and the timestamp. It is encoded onto the URI as:

< uri-prefix >< token >/< timestamp-in-hex >< rel-path >

For example

/protected/dee0ed6174a894113d5e8f6c98f0e92b/43eaf9c5/path/to/file.txt

where the token is generated as

md5("secret" + "/path/to/file.txt" + dechex(time_now()))

with the following configuration in httpd.conf

< Location /protected/ >
AuthTokenSecret "secret"
AuthTokenPrefix /protected/
AuthTokenTimeout 60
< /Location >

The actual file would should be located in

/protected/path/to/file.txt