comp security lab.ppsx
- 2. • Lab 1: Installing and configuring OpenSSL • Lab 2: Introduction and commands used in openSSL • Lab 3: Encryption using conventional algorithms • Lab 4: Symmetric encryption with OpenSSL • Lab 5: Encrypting file using RSA • Lab 6: Asymmetric encryption with OpenSSL
- 3. • Run OpenSSL Installer • using CMD paste the following command • set OPENSSL_CONF=C:Program FilesOpenSSL-Win64binopenssl.cfg • set Path=%Path%;C:Program FilesOpenSSL-Win64bin
- 4. First steps • Open cmd and type openssl • For commands: type help • description of some commands ca To create certificate authorities. dgst To compute hash functions. enc To encrypt/decrypt using secret key algorithms. It is possible to generate using a password or directly a secret key stored in a file. genrsa This command permits to generate a pair of public/private key for the RSA algorithm. password Generation of “hashed passwords”. rsa RSA data management. rsautl To encrypt/decrypt or sign/verify signature with RSA.
- 5. AES cipher-commands • cipher-commands • aes-128-cbc • aes-128-ecb • aes-192-cbc • aes-192-ecb • aes-256-cbc • aes-256-ecb • base64 • Cbc stands for Cipher Blocker Chaining • Ecb stands for Electronic Codebook
- 6. example • Let us create text document named TEST.txt • Write the message that you want To encrpt the test.txt • Open cmd write openssl >enter • Openssl enc -aes-256-ecb -a -salt -in TEST.txt - out cipher.txt • Enter password and verify it
- 7. To decrypt • enc -d -aes-256-ecb -a -salt -in cipher.txt -out plain.txt • Enter the pass word that entered before • Done
- 8. • Conventional Encryption involves transforming plaintext messages into cipher text messages that are to be decrypted only by the intended receiver. Both sender and receiver agree upon a secrete key to be used in encrypting and decrypting. Usually the secrete key is transmitted via public key encryption methods. .
- 9. • Triple DES(Data Encryption Standard) Encryption: • RSA Encryption. ... • Advanced Encryption Standards (AES) • Twofish encryption algorithm. • Blowfish encryption algorithm. • IDEA encryption algorithm. • MD5 encryption algorithm. • HMAC encryption algorithm etc
- 10. • Symmetric encryption is a means of protecting data using a secret key to encrypt (lock) and decrypt (unlock) it. • The sender and recipient share the key or password to gain access to the information. • AES, RC4, DES, RC5, and RC6 are examples of symmetric encryption.
- 12. • Asymmetric encryption is also a process of encrypting data between two parties — but instead of using a single key (as with conventional cryptographic systems), • it uses two unique yet mathematically related keys to do so. • The first key, known as the public key, encrypts your data before sending it over the internet; the other private key decrypts the data on the recipient’s end of the exchange.
- 14. • GENERATING A RSA PRIVATE KEY • Openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits:2048 -out private-key.pem • TO GENERATE A PASSWORD PROTECTED PRIVATE KEY Openssl genpkey -aes256 -algorithm RSA -pkeyopt r • sa_keygen_bits:2048 -out private-key.pem
- 15. • Openssl> pkey -in private-key.pem -out public- key.pem –pubout • TO SEE THE PUBLIC KEY • Openssl> pkey -in public-key.pem -pubin –text
- 16. • example, I will be hashing an arbitrary file on my system using the MD5, SHA1, and SHA384 algorithms. • OpenSSL dgst -md5 use.mp4 • OpenSSL dgst -sha1 use.mp4 • OpenSSL dgst -sha384 use.mp4 Encrypting video file • Openssl enc -aes-256-cbc -e -iter 1000 -salt -in use.mp4 -out unuse.enc
- 17. • Openssl enc -aes-256-cbc -d -iter 1000 -in unuse.enc -out prime.mp4
- 18. Hashing vs Encryption Differences • Hashing is a digital signature orignally designed to check if data was modified Password hashing is a mathematical algorithm that maps data of arbitrary size (often called the "message") to a bit array of a fixed size (the "hash value", "hash", or "message digest"). It is a one-way function, that is, a function which is practically infeasible to invert or reverse the computation
- 19. Cracking • Cracking file passwords using passfab • Cracking windows passwords using usb • Cracking rar passwords using kraken