Thread: Database programming and passwords

  1. #1
    Registered User
    Join Date
    Oct 2002
    Posts
    24

    Database programming and passwords

    What would the algorithm be for creation a application which would enter every possible combination of valid password keyboard characters into a database minimum of 3 chars and maximum of 16 characters.

    Basicly i want to write a application which will create a list of possible passwords and could also be used for a user name list.

    I think you should understand the question but just in case i elaborate.

    Valid Passwords Chars are: a-z, A-Z, 0-9,#,/ \$@*&% and what ever other characters that might be used.

    I want to use those characters and any others to create combinations of them and store them into a database.

    I understand that the the combinations would be in the millions or billions depending on how many unique characters there are and i understand there are limitation on how much one database can hold so can this be done and if so how would i do it.

    Basicly im trying to create an ultimate password list and username list. which i will probably do nothing with except disrtibute it for others use

  2. #2
    Registered User
    Join Date
    Oct 2003
    Posts
    12
    I see no reason to store all possible passwords. If you want to use them for anything usefull you'd have to have some automated way to go thru the list trying every one it would be better to have a loop wich generates a password, tries it then generates the next one.
    if you start with the password "aaa" you need to add 1 to the last charactor making it aab and so on untill it reaches z (or whatever) then make it a again and increment the second charactor when you get to azz increment the 3rd.

  3. #3
    Registered User
    Join Date
    Oct 2002
    Posts
    24
    sounds simple. So why havn't i heard of any password crakers that use this technique. All the ones that i have seen use a text list which appears to be handed down and hand typed over many years.

    Do you know of any brute force password crackers that would do this for both username and passwords. I dont want to waste my time making one if one already exist

  4. #4
    30 Helens Agree neandrake's Avatar
    Join Date
    Jan 2002
    Posts
    640
    the number of passwords generated is too much to handle. chances are the program would crash or the computer would crash or the hard drive would run out of space.

    i'm probably wrong, but I think the way to figure out how many possibilities is like this:

    for three characters,
    26^3
    so to continue down from 16
    26^(16!)
    obviously this includes 2 character and 1 character possibilites, but it's also leaving out other characters that can be used (26 letters in this example, include 52(upper/lower case) and 18 for the numbers and characters listed in the post, not to mention other characters allowed in a password)

    It would probably end up something like

    70^(16!) - 70^(2!)

    just try calculating that
    Environment: OS X, GCC / G++
    Codes: Java, C#, C/C++
    AOL IM: neandrake, Email: neandrake (at) gmail (dot) com

  5. #5
    Yes, my avatar is stolen anonytmouse's Avatar
    Join Date
    Dec 2002
    Posts
    2,544
    70^(16!) - 70^(2!)

    just try calculating that
    Windows calculator says 332329305696010000000000000000.

    The good news is that if you can do a million a second that is only 10538093153729388.6 years which is only 752720 times the estimated age of the universe (14 billion years).

    Excercise for the reader: How long will it take if moore's law holds true for the duration?

    EDIT: Whoops, forgot to minuse the 70^2. You can take off 4900 from the original number and 5 milliseconds from the time taken.
    Last edited by anonytmouse; 11-19-2003 at 08:54 PM.

  6. #6
    30 Helens Agree neandrake's Avatar
    Join Date
    Jan 2002
    Posts
    640
    Originally posted by anonytmouse
    Windows calculator says 332329305696010000000000000000.

    The good news is that if you can do a million a second that is only 10538093153729388.6 years which is only 752720 times the estimated age of the universe (14 billion years).

    Excercise for the reader: How long will it take if moore's law holds true for the duration?

    ROFL Thanks for elaborating my point. Windows calculator can count past 100?
    Environment: OS X, GCC / G++
    Codes: Java, C#, C/C++
    AOL IM: neandrake, Email: neandrake (at) gmail (dot) com

  7. #7
    Yes, my avatar is stolen anonytmouse's Avatar
    Join Date
    Dec 2002
    Posts
    2,544
    The storage reuirements are a measly 2658634445568 exabytes(roughly). This is only 100 billion or so times current global capacity and so is a bit more feasible.

Popular pages Recent additions subscribe to a feed