Information about locks themselves. Questions, tips and lock diagram information should be posted here.
by jarobata » 9 Nov 2006 17:55
Is it doable for a noob to make a master key for a best SFIC lockset with a set up blank keys and the right tools? I read an article which outlined this method:
3.2.1 Notation
Let P denote the number of pin stacks in a lock, with 1 stack representing the first stack (e.g., the one closest to the shoulder of the key) and stack P representing the last (e.g., the stack at the tip of the key). Let D denote the number of distinct key bitting depths in a pin stack, where 1 is the highest bitting (in which the pin stack is raised the most) and D is the lowest (in which the pin stack is raised the least). Assuming that the physical properties of the system place no restrictions on the bitting depth of adjacent pin positions, observe that the number of distinct keys is D^P.
3.2.2 The Attack
For each pin position,p from 1 to P, prepare D-1 test keys cut with the change key bitting at every position except position . At position , cut each of the keys with each possible bitting depth excluding the bitting of the change key at that position. Attempt to operate the lock (“query the oracleâ€) with each of these test keys, and record which keys operate the lock. In a TPP-based system with every pin mastered, exactly one of the test keys for each pin position will operate the lock; the depth of the test key at that position represents the master bitting at that position.
If none of the test keys for a particular position operates the lock, then either that pin is not mastered or it is an RC-based system. In either of these cases, the master key bitting at that position is the same as that of the original change key. Once the master bitting has been determined at each of the P positions, a complete top-level master key can be cut easily.
Observe that our attack consumes P(D-1) key blanks and requires P(D-1)probes of the lock, in the worst case. If it is possible for the attacker to cut keys between probes of the lock, however, a simple optimization reduces the number of blanks consumed to P in the worst case. Rather than cutting D-1 separate blanks per position, the attacker need only use a single key, initially cutting the position under test to the highest depth and re-cutting the same blank successively lower after probing the lock. This reduces the total cost of carrying out the attack to less than about two US dollars in the worst case. This optimized attack still requires P(D-1) probes of the lock in the worse case, of course.
So is this a good method? They imply it's relatively easy but they method is confusing, could someone put the procedure into a summary of simple english? What would be the necessary tools for this operation, I have access to a lock, a key that works in the locks, and a blank key.
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jarobata
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by jarobata » 9 Nov 2006 17:57
I also have a metal file, its says thats all i need but that seems like a difficult proposition.
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jarobata
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by Schuyler » 9 Nov 2006 18:54
It sounds like you're actually asking us to help you amplify your rights in a master keyed system.
Which is a bad idea for a lot of reasons.
very very bad idea.
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Schuyler
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by unbreakable » 9 Nov 2006 18:56
I really doubt you'll get any help AT ALL on this.
You have a total of Two post on asking for help on something that's most likely purpose is for something illegal.
We are hobby pickers and locksmiths, we pick locks for the fun, or as business. You do not seem to be interested in either, so please leave, as you won't get help on anything illegal here.
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unbreakable
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by jarobata » 9 Nov 2006 19:15
unbreakable wrote:I really doubt you'll get any help AT ALL on this.
You have a total of Two post on asking for help on something that's most likely purpose is for something illegal.
We are hobby pickers and locksmiths, we pick locks for the fun, or as business. You do not seem to be interested in either, so please leave, as you won't get help on anything illegal here.
Thats a pretty harsh accusation with absolutely nothing to base it upon. Making a master key for a system of locks when one is lost (my case) or broken is not illegal in any way. Thats like you telling me I can't make a backup copy of a dvd when most dvd burning is done for illegal purposes. I'm sorry I asked, I didn't realize there was a problem. Oh and I have an amateur lock pick set and a manual pick gun which I use for hobby lock picking so once again you were completely wrong but you apparently decided to be an butthole rather and run your mouth before you had any facts.
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jarobata
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by Schuyler » 9 Nov 2006 19:25
If you need a master key for your own system, go to the locksmith who created the system for you. He can likely cut you a new one and be done with it. Toss a spare in a safety deposit box, or keep one at the office and you're sorted.
As unbreakable said, if you were a well established member here, maybe, but you can imagine people come in all the time asking any number of shady things.
Anyway, go to a locksmith and while he's taking care of you, ask about rights amplification. If it's your building anyhow? Well, it's a security risk you should become aquainted with.
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by unbreakable » 9 Nov 2006 19:35
jarobata wrote:unbreakable wrote:I really doubt you'll get any help AT ALL on this.
You have a total of Two post on asking for help on something that's most likely purpose is for something illegal.
We are hobby pickers and locksmiths, we pick locks for the fun, or as business. You do not seem to be interested in either, so please leave, as you won't get help on anything illegal here.
Thats a pretty harsh accusation with absolutely nothing to base it upon. Making a master key for a system of locks when one is lost (my case) or broken is not illegal in any way. Thats like you telling me I can't make a backup copy of a dvd when most dvd burning is done for illegal purposes. I'm sorry I asked, I didn't realize there was a problem. Oh and I have an amateur lock pick set and a manual pick gun which I use for hobby lock picking so once again you were completely wrong but you apparently decided to be an <censored> rather and run your mouth before you had any facts.
I found a reason to base my accusation on- the fact that you simply asked for info on something which is most likely purpose is to be used illegally. Thats why they call it rights amplification. Not creating a master key for a lost lock- rights amplification because it can be used to amplify your access to an area where you would not normally have access. It can be used legally, I agree with you there.
Why not pay a lockie to do it? The key you made would most likely be pretty sketch, especially if hand filed, and not made with a key cutter.
Were you provided with a key code when your master key was given to you? You can use that to get a duplicate made.
Where are the locks? Are they on your work or home? Why not post some pics of your pickset and the SFIC you are trying to make a key for, unattached to anything. That would further solidify that you are a hobby picker trying to make a key to a lock in your possession.
Also, 2 posts on making a master key for a lock is pretty suspicious, even you have to admit that. I have a habit of telling people who are asking about bypass, or something like Rights amplification, to just bug off. If you are an hobby picker trying to make a key to a lock in your possession, sorry I was so harsh.

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unbreakable
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