brute-force | 易学教程

Non Brute Force Solution to Project Euler 25

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问题 Project Euler problem 25: The Fibonacci sequence is defined by the recurrence relation: F n = F n−1 + F n−2 , where F 1 = 1 and F 2 = 1. Hence the first 12 terms will be F 1 = 1, F 2 = 1, F 3 = 2, F 4 = 3, F 5 = 5, F 6 = 8, F 7 = 13, F 8 = 21, F 9 = 34, F 10 = 55, F 11 = 89, F 12 = 144 The 12th term, F 12 , is the first term to contain three digits. What is the first term in the Fibonacci sequence to contain 1000 digits? I made a brute force solution in Python, but it takes absolutely forever

Nmap http-joomla-brute script example?

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问题 This is a relatively obscure topic, but any help is nevertheless appreciated. I am trying to run a brute force test on my website's Joomla login. I was trying to use nmap's http-joomla-brute, but for some reason it does not output neither the process nor does it actually do the brute force with the password list I gave it. Here is my script: nmap -sV --script http-joomla-brute --script-args 'passdb=/Users/abc/Documents/passwords.txt,http-joomla-brute.threads=5,brute.firstonly=true' my.website

Generating every character combination up to a certain word length

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问题 I am doing a security presentation for my Computer and Information Security course in a few weeks time, and in this presentation I will be demonstrating the pros and cons of different attacks (dictionary, rainbow and bruteforce). I am do the dictionary and rainbow attacks fine but I need to generate the bruteforce attack on the fly. I need to find an algorithm that will let me cycle though every combination of letter, symbol and number up to a certain character length. So as an example, for a

Does Apache basic authentication defend brute force attacks?

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Will it shut down & lock up after repeated false password tries, and/or will it add lags in-between retries? Or does this depend on which modules you or your provider install? Thanks! default Apache installation does not do that. usually this is better done by your web application (eg, PHP/JSP) for account attack. for network attack, better not for web servers because it's hard to identify the source due to so many anonymous / transparent proxy / VPN / NAT stuff. once you've implement that, you'd usually get lots of "why I can't connect" complains... 来源： https://stackoverflow.com/questions

Is there a bruteforce-proof hashing algorithm?

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问题 Well, from the discussion of hashing methods weaknesses, I've got that the only ol' good brute-force is efficient to break. So, the question is: Is there a hashing algorithm which is more rigid against brute-force than others? In case of hashing passwords. 回答1: The only protection against brute force is the fact that it takes an inordinately long time to perform a brute force. Brute force works by simply going through every possible input string and trying it, one at a time. There's no way to

Parallel Brute-Force Algorithm

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So I was looking at http://codahale.com/how-to-safely-store-a-password/# and became curious how fast different hash could be bruteforced on a somewhat powerful desktop computer and was tempted to test it Most of the algorithms I've seen though are single-threaded and it struck me that this would be a really interesting challenge in using c# 4.0 Parallel.net/Plinq extensions and concurrent structures (like ConcurrentBag and IProducerConsumer). So my task is as follows, build the most efficient/performant bruteforce checker of a password of n-length and charset[x] using parallelization, ie

Knapsack - brute force algorithm

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问题 I have found this code to solve Knapsack Problem using brute force mechanism (this is mostly for learning, so no need to point out dynamic is more efficient). I got the code to work, and understand most of it. MOST. Here's the question: I've noticed those two conditionals, that I have no idea how they work and why they are in the code - I know they are vital, since any changes I've made caused the algorithm to produce wrong results: // if bit not included then skip if (((i >> j) & 1) != 1)

Exhaustive Search in OptaPlanner does not work on very simple example

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We are trying to create a simple example to test the capabilities of OptaPlanner. In the following we show what we came up with. The problem with our example is that when we are selecting an exhaustive search algorithm for solving the problem, OptaPlanner terminates quickly with the wrong answer, which is always zero, even if zero is not a possible solution available from the ValueRangeProvider. Furthermore the PlanningVariable is not set during solving, as opposed to when local search is used. We tried to change the algorithms in the examples that come with OptaPlanner (e.g. TSP), which

How can I randomly iterate through a large Range?

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问题 I would like to randomly iterate through a range. Each value will be visited only once and all values will eventually be visited. For example: class Array def shuffle ret = dup j = length i = 0 while j > 1 r = i + rand(j) ret[i], ret[r] = ret[r], ret[i] i += 1 j -= 1 end ret end end (0..9).to_a.shuffle.each{|x| f(x)} where f(x) is some function that operates on each value. A Fisher-Yates shuffle is used to efficiently provide random ordering. My problem is that shuffle needs to operate on an

Non Brute Force Solution to Project Euler 25

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Project Euler problem 25 : The Fibonacci sequence is defined by the recurrence relation: F n = F n−1 + F n−2 , where F 1 = 1 and F 2 = 1. Hence the first 12 terms will be F 1 = 1, F 2 = 1, F 3 = 2, F 4 = 3, F 5 = 5, F 6 = 8, F 7 = 13, F 8 = 21, F 9 = 34, F 10 = 55, F 11 = 89, F 12 = 144 The 12th term, F 12 , is the first term to contain three digits. What is the first term in the Fibonacci sequence to contain 1000 digits? I made a brute force solution in Python, but it takes absolutely forever to calculate the actual solution. Can anyone suggest a non brute force solution? def Fibonacci