Beginner in java and need your help about DES

Question

hello,
I m a new guy in java programming and learn from many books.I m making a website and portal right now and dying need your help about DES.my portal (using java) requires somebody to make a login name and a password.I m done with the server and client things and rite now stuck with this "DES" stuff.
so I make some conditions and algorithm below..
1. when a user login,the password is encrypted.at this point,cleartext(id) and encryption (M,N) are involve.
2. then the key is changed based on algorithm.
3.the key changed by key(id) is received and the original text should be encrypted.
the algorithm
1. the original text x1.x2.x3.x4.x5.x6.x7.x8 (64 bits)
2. encypt the password
a. Each character is changed into an int type by the ASCII code, and let the 1st bit be an odd number parity bit.
b.The 1st bit of the 1st character in (IP) is set to '1', and the 8th bit of the 8th character as '64'.
c.the rest (IP) is like this
1 2 3 4 5 6 7 8
0 # 58 50 42 34 26 18 10 2
8 # 60 52 44 36 28 20 12 4
16 # 62 54 46 38 30 22 14 6
24 # 64 46 48 40 32 24 16 8
32 # 57 49 41 33 25 17 9 1
40 # 59 51 43 35 27 19 11 3
48 # 61 53 45 37 29 21 13 5
56 # 63 55 47 39 31 23 15 7
d. and lastly,from above,,it should be done like this
1 2 3 4 5 6 7
0 # 40 8 48 16 56 24 64 32
8 # 39 7 27 15 55 23 53 31
16 # 38 6 26 14 54 22 52 30
24 # 37 5 25 13 53 21 51 29
32 # 36 4 24 12 52 20 50 28
40 # 35 3 23 11 51 19 49 27
48 # 34 2 21 10 50 18 48 26
56 # 33 1 20 9 49 17 47 25
e. key y1,y2,y3,y4,y5,y6,y7,y8 (64bit)
f. generate the key based on ID
a. Each character is changed into an int type by the ASCII code, and let the 1st bit be an even number parity bit.
b.the process is repeat again.
anybody has an idea to help me with the sample program?
thanks in advance...

Answer 1

just ask about a simple program how to receive a
password from somebody and change it to a key..and
then confirm it with DES.Once again I have a problem understanding what you are asking.
Are you trying to use the password as a key to encrypt some 'standard thing' and place this encrypted value in a database? If so then look in the JCE for 'password based encryption' such as PBEWithMD5AndDes. This seems back to front to me but I can see nothing wrong with the approach since the 'standard thing' you would encrypt is in effect a key. If this is for a commercial application then I would find a security expert to evaluate your proposal!
In my experience it is more normal to encrypt the user's password with DES and store the result in the database. To do this just look in the JCE for DES encryption and consider using DES with CBC and PKCS5 padding. Also, consider encrypting the concatenation of the user's 'user name' with the password as this will (almost certainly) avoid having two encrypted values in the database that are the same even if two users have the same password.
For both of these you might consider using Base64 or Hex to turn you encrpted bytes into ASCII characters before trying to store them in your DB.