to wrong results
3 problems found with DES_ENCRYPT/DES_DECRYPT :
1. The max length was not calculated properly. Fixed in fix_length_and_dec()
2. DES_ENCRYPT had a side effect of sometimes reallocating and changing
the value of its argument. Fixed by explicitly pre-allocating the necessary
space to pad the argument with trailing '*' (stars) when calculating the
DES digest.
3. in DES_ENCRYPT the string buffer for the result value was not
reallocated to the correct size and only string length was assigned to it.
Fixed by making sure there's enough space to hold the result.