googauth

Documentation

Index

• func ComputeCode(secret string, value int64) int
• type OTPConfig
  • func (c *OTPConfig) Authenticate(password string) (bool, error)
  • func (c *OTPConfig) GenerateURI(user string) (string, error)

Functions

func ComputeCode

func ComputeCode(secret string, value int64) int

ComputeCode computes the response code for a 64-bit challenge 'value' using the secret 'secret'. To avoid breaking compatibility with the previous API, it returns an invalid code (-1) when an error occurs, but does not silently ignore them (it forces a mismatch so the code will be rejected).

Types

type OTPConfig

type OTPConfig struct {
	Secret        string // 80-bit base32 encoded string of the user's secret
	WindowSize    int    // valid range: technically 0..100 or so, but beyond 3-5 is probably bad security
	DisallowReuse []int  // timestamps in the current window unavailable for re-use
	UTC           bool   // use UTC for the timestamp instead of local time
}

OTPConfig is a one-time-password configuration. This object will be modified by calls to Authenticate and should be saved to ensure the codes are in fact only used once.

func (*OTPConfig) Authenticate

func (c *OTPConfig) Authenticate(password string) (bool, error)

Authenticate a one-time-password against the given OTPConfig Returns true/false if the authentication was successful. Returns error if the password is incorrectly formatted (not a zero-padded 6 or non-zero-padded 8 digit number).

func (*OTPConfig) GenerateURI

func (c *OTPConfig) GenerateURI(user string) (string, error)

GenerateURI generates a URI that can be turned into a QR code to configure a Google Authenticator mobile app. It respects the recommendations on how to avoid conflicting accounts.

See https://github.com/google/google-authenticator/wiki/Conflicting-Accounts