Operation request: HKDF

[mauricelam]

Summary

Please add HKDF as an operation: RFC 5869

This document specifies a simple Hashed Message Authentication Code
(HMAC)-based key derivation function (HKDF), which can be used as a
building block in various protocols and applications. The key
derivation function (KDF) is intended to support a wide range of
applications and requirements, and is conservative in its use of
cryptographic hash functions.

Input values:

• IKM (Input key material)
• salt
• hash (enum: SHA-1, SHA-256, SHA-384, SHA-512)
• info
• L (output length)

See also HkdfParams for reference

Example Input

• Hash = SHA-256
• IKM = 0x000102030405060708090a0b0c0d0e0f
  101112131415161718191a1b1c1d1e1f
  202122232425262728292a2b2c2d2e2f
  303132333435363738393a3b3c3d3e3f
  404142434445464748494a4b4c4d4e4f (80 octets)
• salt = 0x606162636465666768696a6b6c6d6e6f
  707172737475767778797a7b7c7d7e7f
  808182838485868788898a8b8c8d8e8f
  909192939495969798999a9b9c9d9e9f
  a0a1a2a3a4a5a6a7a8a9aaabacadaeaf (80 octets)
• info = 0xb0b1b2b3b4b5b6b7b8b9babbbcbdbebf
  c0c1c2c3c4c5c6c7c8c9cacbcccdcecf
  d0d1d2d3d4d5d6d7d8d9dadbdcdddedf
  e0e1e2e3e4e5e6e7e8e9eaebecedeeef
  f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff (80 octets)
• L = 82

Example Output

      0xb11e398dc80327a1c8e7f78c596a4934
      4f012eda2d4efad8a050cc4c19afa97c
      59045a99cac7827271cb41c65e590e09
      da3275600c2f09b8367793a9aca3db71
      cc30c58179ec3e87c14c01d5c1f3434f
      1d87 (82 octets)