Generated: Monday, November 14, 2011, 09:18:12  Copyright © 2011 , Kurt Nørmark  
Reference Manual of the Crypt Library
Kurt Nørmark © normark@cs.aau.dk Department of Computer Science, Aalborg University, Denmark.
LAML Source file: lib/crypt.scm
A password crypting library. This is a primitive encrypting based on a fairly elaborate transformation of string to another string. The sheer complexity of the program below adds to the value of the encryption. The main function is: cryptstring. This library requires the general library.

1 The main crypting function. 
The main crypting function is cryptstring below. 

cryptstring 
Form  (cryptstring inputpassword) 
Description  A poor mans password crypting function. The one and only external function of this library. This cryptation will immediately be broken by experts! However, it is better than nothing in practical situations. 

2 Helping functions. 
This section contains a few helping functions which may be of some use in other situations. 

extendstring 
Form  (extendstring str extension) 
Description  Extend string st by extension by means of string merging. 

permutestring 
Form  (permutestring str permutationvector) 
Description  Return a permuation of the string carried out determinitically by means of permutationvector The second parameter, permutationvector, is a vector of positive integers 

calculateexchangeposition 
Form  (calculateexchangeposition n m permutationvector) 
Description  Return a number between n and m (actually m  1), calculated by means of permutationvector n < m 

shiftupanddown 
Form  (shiftupanddown str shiftvector) 
Description  Shift the characters in the string str up and down by means of a shiftvector. A shiftvector is a vector of integers. 
