Dead simple Golang OTP (One Time Password) library for both HOTP and TOTP without any dependency following both official RFC6238 and RFC4226 rules on the implementation.
A time-based OTP, using the time for the message validation.
secret := entica.RandSecret() // base32 string (A-Z and 2-7) with length of 32 chars
totp := entica.NewTOTP(secret) // new default totp (sha1) with 6 digit result
totp.Get() // 918399
// or with more specific
secret := "IDI5FG3XTZE26AONPVRIVQP4DN2DV54J"
totp := entica.NewTOTPSHA(7, sha512.New, secret)
totp.Get() // 9183993
totp.Compare("codeToCheck") // return valid status
totp.At(time.Now().Sub(time.Hour * 3)) // return code at specific time, 3 hours earlier
totp.CodeAtUnix(1646373) // return code at specific unix timeHMAC-Based OTP, using the counter value for the message validation.
secret := entica.RandSecret("SomeSalt")
hotp := entica.HOTP{
Hash: entica.Sha1,
Digits: 6,
Secret: secret, // 32bit string secret
Counter: 1,
}
// or
hotp := entica.NewDefaultHOTP(secret, counter)
hotp.Check("codeToCheck") // return code at current time
hotp.CodeAtCounter(10) // return code at specific counter value
hotp.CurrCounter() // return counter value MIT License
Copyright (c) 2020 Aditya Kresna
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