I want to compare password and use bcrypt library but CompareHashAndPassword method is very slow. Why this method is slow?
var b []byte = []byte("1234")
var bx []byte = []byte("$2a$14$RWV9NhWmlQmSoV9toM/k9OIzaNcYssCiauPVAljiX2NGhqvyxcOMy")
fmt.Println("Start Compare: ", time.Now().Format("2006-01-02 15:04:05.000000"))
err := bcrypt.CompareHashAndPassword(bx, b)
fmt.Println("Completed Compare: ", time.Now().Format("2006-01-02 15:04:05.000000"))
fmt.Println("------------------------")
Result:
Start Compare: 2018-03-22 22:53:09.142380
Completed Compare: 2018-03-22 22:53:10.347585
Can you help me?
Slowness is a design feature of bcrypt, because if it was fast, it would be easy to brute-force password hashes. From Wikipedia:
Besides incorporating a salt to protect against rainbow table attacks, bcrypt is an adaptive function: over time, the iteration count can be increased to make it slower, so it remains resistant to brute-force search attacks even with increasing computation power.