cutil

Documentation

Index

• func ConstantTimeCompare(d1, d2 []byte) bool
• type NonceCounter
  • func NonceCounterForAEAD(aead cipher.AEAD) NonceCounter
  • func (nonce NonceCounter) Increment() (err error)
  • func (nonce NonceCounter) Len() int

Functions

func ConstantTimeCompare

func ConstantTimeCompare(d1, d2 []byte) bool

ConstantTimeCompare checks if two slices are equal and returns true if they are, false otherwise. It uses constant-time comparison. It's not contant time when len(d1) != len(d2)

Types

type NonceCounter

type NonceCounter []uint8

NonceCounter is preallocated slice of specified size, which can be efficiently incremented by one in order to produce unique nonces for data encryption.

NOTE: NocneCounter IS NOT CONSTANT TIME!!! Be aware that this counter leaks(or may leak) count of chunks encrypted already. Usually this is not problem, since attacker knows anyway how many chunks were encrypted.

func NonceCounterForAEAD

func NonceCounterForAEAD(aead cipher.AEAD) NonceCounter

NonceCounterForAEAD creates nonce counter appropriate for specified AEAD cipher.

func (NonceCounter) Increment

func (nonce NonceCounter) Increment() (err error)

Increment assigns next unique value to this nonce counter. If it's not possible without overflowing or changing nonce size then error is returned.

func (NonceCounter) Len

func (nonce NonceCounter) Len() int

Len retuns size of nonce generated by this nonce counter.