Question

The message is padded to

(a) 1024 bits

(b) 512 bits

(c) Odd multiple of 256 bits

(d) Odd multiple of 512 bits

I have been asked this question in an international level competition.

My doubt is from Whirlpool Algorithm in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security

Answer 1

The correct answer is (c) Odd multiple of 256 bits

Easy explanation: The message in Whirlpool is padded to an odd multiple of 512 bits.