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Writing a code

$10-30 USD

Closed
Posted about 7 years ago

$10-30 USD

Paid on delivery
Encryption Decryption program Write a program in any language you wish that accepts plaintext, a password (either through prompting the user or on the command line), and whether to encrypt or decrypt. Your program should, if available, use AES with a 128 bit key (derived from the password) in ECB mode to either encrypt or decrypt the plaintext given by the user. If AES-128-ECB mode is not available, first try to use AES in some other mode, then whatever will work. In any case, let me know what cipher was used. Print the encrypted output in Base64 to the console. A user should be able to run the program to encrypt some text to obtain ciphertext. The user should be able stop the program and later run the program again and use the same key to decrypt the cipher text. Using screenshots, show that your program works by encrypting something with one run of the program and decrypting the resulting ciphertext in a second run of the program. Submit the screenshots and your source code when your program is complete. Hints: Do not attempt to implement AES on your own. Instead, use the libraries that come with almost every programming language. For example, Java has the Java Cryptography Extensions or the BouncyCastle library, both of which are freely available. Do not use the programming language to simply call the OpenSSL command-line programs. Some languages have bindings to OpenSSL, which are fine to use.
Project ID: 13131287

About the project

20 proposals
Remote project
Active 7 yrs ago

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20 freelancers are bidding on average $35 USD for this job
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Hello. What is target platform? Windows? Linux? Meantime I have experience how to link with C/C++ and OpenSSL libraries (Not calling command line, of course)
$31 USD in 1 day
4.9 (1346 reviews)
7.7
7.7
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I am very proficient in c and c++. I have 16 years c++ developing experience now, and have worked for more than 7 years. My work is online game developing, and mainly focus on server side, using c++ under Linux environment. I made many great projects using c++, for example, I made the tools which could convert java codes into c++ scripts, of course garbage collection included, this was very similar to a compiler, and was very complex. I also made our own mobile game using c++, I can show you the demo of client, if you like. I am very proficient in java also. I have a very good review on Freelancer.com, I never miss a project once I accept the job, you can check my review. Trust me, please let expert help you.
$120 USD in 3 days
4.9 (160 reviews)
7.0
7.0
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i am software engineer i made a lot of projects especially in the security sector so i can finish your project with high quality
$30 USD in 1 day
4.9 (29 reviews)
5.2
5.2
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Hello, I have 28 years experience developing C/C++ apps, more than 20 years developing in Java, and 10+ years working with Cryptographic Algorithms. This program seems fairly simple, so I am sure I will be able to provide it to you quickly, reliably and in a way that will totally suit your needs. Please consider hiring me for this task. Best regards, Joeldo
$41 USD in 1 day
5.0 (10 reviews)
4.5
4.5
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hey! i am software engineer professionally and have experience, you can trust me and i assure you that you will not be disappointed, thanks :)
$20 USD in 1 day
5.0 (5 reviews)
3.4
3.4
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Hello. Your quality parameters will be applied to the project. Would be great to discuss them in advance in order to agree on how will we include them. I have coordinated software deployment on premise and on cloud computing environments, especially targeting Windows or Linux distributions like Suse, Fedora, RHEL and Ubuntu, using Expect for automation. The project could integrate with Velocity in order to generate the views, JAXB or Jackson to manipulate XML or JSON, and MyBatis or Hibernate to handle persistence. If you rather other frameworks, we shall take a look at them. My skills include the use of SCMs like Git; SQL and NoSQL databases; automatic tests with JUnit or TestNG; JMeter; messaging with tools like ActiveMQ, Tibco and Kafka; caching solutions; Maven, Gradle, and the deployment of continuous integration systems. Take a look at my résumé and if you have any questions, please let me know.
$30 USD in 1 day
5.0 (4 reviews)
2.8
2.8
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Hello! I work in Java and I can develope your program in it exactly how it is described above.I can design it if you want for graphical user interface (with pressing a button if you want to decrypt or encrypt And entering the password hidden with asterisks).So if you think go on and contact me for the project .
$30 USD in 1 day
5.0 (2 reviews)
1.8
1.8
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Hello, I did tasks similar to that one you need before. I have a good experience in java development and you can trust me. You will get what you need in a professional manner, I promise. I am waiting for your message to start the work :) :)
$20 USD in 1 day
5.0 (2 reviews)
1.4
1.4
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Hello, I'm Dylan Moore. I hope to have the opportunity to help with your project and I look forward to working with you soon. The project definitely sounds do able and I'll use JavaFX for the GUI.
$20 USD in 1 day
0.0 (0 reviews)
0.0
0.0
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Hello , i am working for a payment gateway company and i daily deal with encryption and decryption of data with various Advance encryption standard algorithm. I designed the Mastercard CMS where it perform all encryption via AES CBC, ECB and CTR mode. Now i want to ask few things that you want to use symmetric key algorithm for each run of program. so if you want same key derived for each then we use either "hardcoded" key which may cause security issue or derive key from some fixed user input. Also if timing for enc and dec is not issue for u then can use Assymetric encryption also. Of you find me suitable for this task let me help. Thank, Ayush khandelwal.
$15 USD in 1 day
0.0 (0 reviews)
0.0
0.0
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I have over 10 years of software development experience mainly in Java using Windows and Linux. My skills and experience with BouncyCastle and PGP encryption will get you the results you want. -------------------------------------------- AES - 128 bit - PBKDF2WithHmacSHA1 -------------------------------------------- Welcome to the Encryption/Decryption CMD tool. Type 'exit' to quit Enter E to Encrypt or D to Decrypt> E Enter text to Encrypt> Hello World!!! Enter password to Encrypt> Pass Input> Hello World!!! Input Encrypted> k3kbNj8jPIvb4DA5m3RzwQ== Enter E to Encrypt or D to Decrypt> D Enter text to Decrypt> k3kbNj8jPIvb4DA5m3RzwQ== Enter password to Decrypt> Pass Input> k3kbNj8jPIvb4DA5m3RzwQ== Input Decrypted> Hello World!!! Enter E to Encrypt or D to Decrypt> exit Good bye!
$30 USD in 21 days
0.0 (0 reviews)
0.0
0.0
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Hello, i made in Qt a program that i think just fits with what you are asking for, i would like you to take a look and let me know if it's what you need. I already took the pictures of the program an the code
$25 USD in 3 days
0.0 (0 reviews)
0.0
0.0
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I feel that I am a worthy candidate for the project because of my experience in the field of cyber security.I have a great amount of experience in working with and cracking various cryptosystems such as AES,RSA,DES,Rabin etc. I have done an internship in Computer and Network Security. I have also done a voluntary internship in Cyber security Content writing. I frequently participate in online Capture the Flag contests which gave me a huge amount of experience in the field of security(Web, System and Network and Cryptography).I will also be working in Cyber security starting this summer. I hope that the above qualifications help to prove that I have sufficient experience and motivation to take up and complete the project effectively.
$25 USD in 1 day
0.0 (0 reviews)
0.0
0.0
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A proposal has not yet been provided
$20 USD in 2 days
0.0 (0 reviews)
0.0
0.0

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Flag of UNITED STATES
Newyork, United States
4.9
26
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Member since Jan 29, 2017

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