Cryptography Lab

Question 1

What is the primary use of OpenSSL?

A. To manage public-key infrastructures.
B. To implement cryptographic functions.
C. To compress encrypted files.
D. To store cryptographic keys securely.

Answer 1

B

Question 2

Which command generates a private key using OpenSSL?

A. openssl genrsa
B. openssl enc
C. openssl sign
D. openssl x509

Answer 2

A

Question 3

Which library is a fork of OpenSSL?

A. BoringSSL
B. GnuPG
C. LibreSSL
D. Crypto++

Answer 3

C

Question 4

What is the main characteristic of symmetric cryptography?

A. It uses a public and private key pair.
B. It uses the same key for encryption and decryption.
C. It only works on plaintext.
D. It requires a Certificate Authority (CA).

Answer 4

B

Question 5

Which command encrypts a file using AES in OpenSSL?

A. openssl genrsa
B. openssl dgst
C. openssl enc
D. openssl hash

Answer 5

C

Question 6

Which of the following is a symmetric encryption algorithm?

A. RSA
B. AES
C. ECC
D. Diffie-Hellman

Answer 6

B

Question 7

What is a key feature of asymmetric cryptography?

A. Uses the same key for encryption and decryption.
B. Requires no keys for encryption.
C. Uses a public and private key pair.
D. Encrypts only small amounts of data.

Answer 7

C

Question 8

Which algorithm is commonly used in asymmetric cryptography?

A. AES
B. RSA
C. DES
D. MD5

Answer 8

B

Question 9

What does the openssl rsautl command do?

A. Generates RSA keys.
B. Signs a message using RSA.
C. Encrypts or decrypts data using RSA.
D. Creates a self-signed certificate.

Answer 9

C

Question 10

What is the primary purpose of a hash function?

A. To compress data.
B. To verify data integrity.
C. To encrypt data.
D. To generate keys.

Answer 10

B

Question 11

Which of these is a common cryptographic hash algorithm?

A. RSA
B. AES
C. SHA-256
D. Diffie-Hellman

Answer 11

C

Question 12

What does the openssl dgst command do?

A. Encrypts a file.
B. Generates a hash.
C. Creates a private key.
D. Validates a digital certificate.

Answer 12

B

Question 13

What is the primary advantage of ECC over RSA?

A. Faster encryption.
B. Requires shorter keys for equivalent security.
C. Uses symmetric encryption.
D. Supports larger ciphertexts.

Answer 13

B

Question 14

What type of cryptography is ECC classified as?

A. Symmetric
B. Asymmetric
C. Hash-based
D. Quantum-resistant

Answer 14

B

Question 15

Which command is used to generate an ECC key pair in OpenSSL?

A. openssl genrsa
B. openssl ecparam
C. openssl enc
D. openssl sign

Answer 15

B

Question 16

What is the primary purpose of Diffie-Hellman?

A. Encrypting data.
B. Hashing data.
C. Secure key exchange.
D. Creating digital signatures.

Answer 16

C

Question 17

What mathematical problem underpins Diffie-Hellman?

A. Factoring large primes.
B. Solving discrete logarithms.
C. Modular addition.
D. Matrix multiplication.

Answer 17

B

Question 18

Which OpenSSL command generates Diffie-Hellman parameters?

A. openssl genrsa
B. openssl dhparam
C. openssl enc
D. openssl x509

Answer 18

B

Question 19

What is a primary purpose of a digital signature?

A. Compressing data.
B. Ensuring data integrity and authenticity.
C. Encrypting data.
D. Performing key exchanges.

Answer 19

B

Question 20

Which algorithm is commonly used for creating digital signatures?

A. SHA-256
B. AES
C. RSA
D. MD5

Answer 20

C

Question 21

What does the openssl dgst -sign command do?

A. Verifies a digital signature.
B. Signs data using a private key.
C. Encrypts data.
D. Generates a key pair.

Answer 21

B

Question 22

What is the primary role of a digital certificate?

A. To encrypt files.
B. To verify the identity of a public key holder.
C. To hash data for verification.
D. To generate symmetric keys.

Answer 22

B

Question 23

What is a Certificate Authority (CA)?

A. An organization that issues digital certificates.
B. A tool for encrypting data.
C. A private key generator.
D. A type of digital signature.

Answer 23

A

Question 24

Which command creates a self-signed certificate in OpenSSL?

A. openssl enc
B. openssl req -x509
C. openssl dhparam
D. openssl rsautl

Answer 24

B

Question 25

What is the primary use of S/MIME? A. Encrypting files on disk. B. Securing email communication. C. Generating private keys. D. Signing digital certificates.

Answer 25

B

Question 26

What type of cryptography does S/MIME primarily use? A. Symmetric encryption. B. Asymmetric encryption. C. Hashing algorithms. D. Steganography.

Answer 26

B

Question 27

Which command encrypts an email using OpenSSL? A. openssl enc B. openssl smime C. openssl sign D. openssl dhparam

Answer 27

B

Question 28

What is the primary function of SSL/TLS? A. Encrypting network communication. B. Hashing passwords for storage. C. Generating symmetric keys. D. Compressing large files.

Answer 28

A

Question 29

Which protocol replaced SSL? A. TLS B. IPSec C. HTTPS D. S/MIME

Answer 29

A

Question 30

What is the purpose of a cipher suite in TLS? A. To generate keys for encryption. B. To define encryption and authentication algorithms. C. To verify digital certificates. D. To hash passwords for authentication.

Answer 30

B

Question 31

What does OCSP stand for? A. Online Certificate Signing Protocol. B. Online Certificate Status Protocol. C. OpenSSL Certificate Signing Protocol. D. Open Certificate Secure Protocol.

Answer 31

B

Question 32

What is the primary function of OCSP? A. To validate digital signatures. B. To check the revocation status of a certificate. C. To generate private keys. D. To compress certificate data.

Answer 32

B

Question 33

Which command checks certificate status using OCSP in OpenSSL? A. openssl req B. openssl ocsp C. openssl x509 D. openssl dgst

Answer 33

B

Question 34

What is a key feature of ECC compared to RSA? A. It requires a Certificate Authority (CA). B. It is faster but less secure than RSA. C. It provides equivalent security with shorter keys. D. It is only used for hashing.

Answer 34

C

Question 35

Which mathematical concept is foundational to ECC? A. Prime factorization. B. Elliptic curves over finite fields. C. Discrete Fourier Transform. D. Modular exponentiation.

Answer 35

B

Question 36

What does S/MIME provide for email communication? A. Encryption and digital signing. B. Data compression and decryption. C. Key generation and certificate revocation. D. Symmetric key exchange.

Answer 36

A

Question 37

Which file format is commonly used for S/MIME certificates? A. PEM B. DER C. PKCS#12 D. All of the above

Answer 37

D

Question 38

What is the purpose of a TLS handshake? A. To encrypt data before transmission. B. To establish a secure connection and exchange keys. C. To hash passwords for storage. D. To validate the client’s IP address.

Answer 38

B

Question 39

Which command generates a certificate signing request (CSR) in OpenSSL? A. openssl enc B. openssl req -new C. openssl x509 D. openssl genrsa

Answer 39

B

Question 40

What is the OpenSSL command to display the details of a certificate? A. openssl req -new B. openssl enc -decrypt C. openssl x509 -in certificate.pem -text D. openssl verify

Answer 40

C

Question 41

Which command encrypts a file with AES-256-CBC in OpenSSL? A. openssl genrsa -aes256 B. openssl enc -aes-256-cbc -in file.txt -out file.enc C. openssl dhparam -aes256 D. openssl x509 -aes256

Answer 41

B

Question 42

How do you decrypt a file encrypted with AES in OpenSSL? A. openssl aes -decrypt -in file.enc -out file.txt B. openssl enc -d -aes-256-cbc -in file.enc -out file.txt C. openssl enc -decrypt -in file.enc -out file.txt D. openssl aes -d -in file.enc -out file.txt

Answer 42

B

Question 43

What is the OpenSSL command to generate an RSA key pair? A. openssl req -x509 B. openssl enc -rsa C. openssl genrsa -out private.key 2048 D. openssl rsa -generate

Answer 43

C

Question 44

Which command extracts the public key from an RSA private key? A. openssl rsa -in private.key -pubout -out public.key B. openssl genrsa -pubkey -out public.key C. openssl x509 -pubout -key private.key D. openssl enc -pubkey -out public.key

Answer 44

A

Question 45

How do you use OpenSSL to encrypt data with an RSA public key? A. openssl rsa -encrypt -in file.txt -out file.enc B. openssl rsautl -encrypt -inkey public.key -pubin -in file.txt -out file.enc C. openssl enc -rsa -in file.txt -out file.enc D. openssl genrsa -encrypt -out file.enc

Answer 45

B

Question 46

What is the OpenSSL command to decrypt data encrypted with RSA? A. openssl rsa -decrypt -in file.enc -out file.txt B. openssl genrsa -decrypt -in file.enc -out file.txt C. openssl rsautl -decrypt -inkey private.key -in file.enc -out file.txt D. openssl enc -decrypt -rsa -in file.enc -out file.txt

Answer 46

C

Question 47

Which OpenSSL command generates a SHA-256 hash of a file? A. openssl dgst -sha256 file.txt B. openssl enc -sha256 file.txt C. openssl genhash -sha256 file.txt D. openssl x509 -hash -sha256 file.txt

Answer 47

A

Question 48

How do you verify the integrity of a file using its hash in OpenSSL? A. openssl verify -sha256 file.txt B. openssl dgst -sha256 -verify signature.sig -signature hash file.txt C. openssl enc -verify -hash file.txt D. openssl hash -verify -sha256 file.txt

Answer 48

B

Question 49

Which command creates a digital signature for a file using OpenSSL? A. openssl rsa -sign -in file.txt -out signature.sig B. openssl dgst -sha256 -sign private.key -out signature.sig file.txt C. openssl enc -sign -key private.key -out signature.sig file.txt D. openssl sign -key private.key -in file.txt -out signature.sig

Answer 49

B

Question 50

How do you verify a digital signature with OpenSSL? A. openssl verify -signature signature.sig -pubin public.key -in file.txt B. openssl rsa -verify -in file.txt -signature signature.sig -pubkey public.key C. openssl dgst -sha256 -verify public.key -signature signature.sig file.txt D. openssl enc -verify -sha256 -key public.key -signature signature.sig -in file.txt

Answer 50

C