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JCE, BlowFish, CBC. Crypt/Decrypt homework.

$100-150 USD

In Progress
Posted about 17 years ago

$100-150 USD

Paid on delivery
In this task you will have to crypt a message using JCE, decrypt, then implement CBC-modus, do a hybrid encryption and several test to make sure that your implementation works 100% correct. You will also need to decrypt a encrypted message and get correct results. Please do not bid on this project if you are not 100% professionals with practice in Java/JCE. You must also be able to write GOOD documentation to your work as its extremely important. In your bid please include what kind of practice do you have with JCE. Please read full version of description. ## Deliverables Task 1. You have to crypt clear text message using JCE, then decrypt encrypted message and check if the encrypted text are identical clear text you have encoded. In this task you must use: • Use JCE to get “Blowfish/CBC/PKCS5Padding?? or depending on your Java version “Blowfish/CBC/PKCS#5?? Cipher-object. • Create a key using SecretKeySpec, insert initialize vector with IvParameterSpec • Convert text to byte-array that can be crypt, decrypt and converted back to original text message. You must document each and every step of this task. Documentation are extremely important. Task 2 After getting basic understanding on how JCE uses in task 1, you will have to implement CBC-modus and PKCS#5-padding without use of JCE. Implementation of crypto-algorithm Blowfish will be provided, but solution does not have to integrate with it. Cipher you will code in this task will be used as bible function. To control job done in task 2 you will have to decrypt following message (given in hexadecimal base16): 1. B4C6 140F A7A6 BC8D 6016 42C7 02D2 6988 E45D E9B7 E7FE 5370 973E F923 3625 9FEC 0119 48AA D615 5E89 7C38 FD14 8A5E 0378 2. B06A C6FD E556 1A0C B05C B0C7 5DF5 A3E4 3. D3A1 17A3 C103 30F8 9273 42AA 94E4 29A4 8FF5 063B 605D F33A 4. 39E7 5BFD D1F4 5801 Key for all messages is 7fc8c4ed3a8de7fe9e7b1b09272f6621. Initialize vector IV is set to be all null values. Correct decrypt of 4 messages will give understandable sentences. You will have to encrypt a random message using your own implementation and try to decrypt it using JCE and vice versa. You must document each and every step of this task. Documentation are extremely important. Task 3 Hybrid encryption. Use RSA to create shared public key par then use that key to crypt the main data encrypted with blowfish and in yours CBC modus. Classes like ([login to view URL]) and class’s to construct messages will be provided ([login to view URL]). You must document each and every step of this task. Documentation are extremely important. --- --- --- 1. Working source code in Java with dump of test results 2. Full and COMPLETE documentation on 5-10 describing your work in each task. 3. Decrypted messages. --- --- --- 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform Java, JCE, BlowFish, CBC, RSA English documentation.
Project ID: 2840355

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Remote project
Active 17 yrs ago

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$127.50 USD in 8 days
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