totally

Types

Otp

opaque </>

One Time Password type

pub opaque type Otp

TotpConfig

opaque </>

Configuration for the TOTP. Create one with new and customize it with the set_* functions.

pub opaque type TotpConfig

TotpError

</>

pub type TotpError {
  InsecureSecret
  InvalidPeriod
  InvalidOtp
  InvalidOtpLength
}

Constructors

```
InsecureSecret
```
```
InvalidPeriod
```
```
InvalidOtp
```
```
InvalidOtpLength
```

Values

is_valid

</>

pub fn is_valid(
  secret secret: BitArray,
  input totp_input: String,
) -> Result(Bool, TotpError)

Checks if the given TOTP input matches the current code for the secret. Does not check for replay attacks. Use is_valid_with_last_use or is_valid_from_config with set_last_use for replay protection.

is_valid_from_config

</>

pub fn is_valid_from_config(
  config: TotpConfig,
  input totp_input: String,
) -> Bool

Checks if the given TOTP input matches the current code for the config. Automatically uses the current time for verification.

is_valid_with_last_use

</>

pub fn is_valid_with_last_use(
  secret secret: BitArray,
  input totp_input: String,
  last_use last_use: timestamp.Timestamp,
) -> Result(Bool, TotpError)

Checks if the given TOTP input matches the current code for the secret, rejecting codes that were already used in the same time window as last_use.

new

</>

pub fn new(secret: BitArray) -> Result(TotpConfig, TotpError)

Creates a TOTP configuration with the given secret and default values: algorithm: Sha1, period: 30, digits: 6. These are the most commonly used TOTP settings. The secret must be at least 16 bytes (128 bits).

otp_to_string

</>

pub fn otp_to_string(otp: Otp) -> String

Converts the OTP to a string.

otpauth_uri

</>

pub fn otpauth_uri(
  secret secret: BitArray,
  issuer issuer: String,
  account account_name: String,
) -> Result(String, TotpError)

Generates an otpauth URI for the given secret, issuer and account name. The secret must be at least 16 bytes (128 bits). The otpauth URI is used to generate QR codes for TOTP.

otpauth_uri_from_config

</>

pub fn otpauth_uri_from_config(config: TotpConfig) -> String

Generates an otpauth URI for the given TOTP configuration.

secret

</>

pub fn secret() -> BitArray

Generates a random 20 byte secret. 20 bytes is the recommended size according to the HOTP RFC4226 (https://tools.ietf.org/html/rfc4226#section-4).

secret_with_size

</>

pub fn secret_with_size(size: Int) -> Result(BitArray, TotpError)

Generates a random secret with the given size. Must be at least 16 bytes.

set_account

</>

pub fn set_account(
  config: TotpConfig,
  account: String,
) -> TotpConfig

Sets the account for the TOTP configuration.

set_algorithm

</>

pub fn set_algorithm(
  config: TotpConfig,
  algorithm: TotpAlgorithm,
) -> TotpConfig

Sets the algorithm for the TOTP configuration. Most commonly used is Sha1.

set_digits

</>

pub fn set_digits(
  config: TotpConfig,
  digits: Digits,
) -> TotpConfig

Sets the digits for the TOTP configuration.

set_issuer

</>

pub fn set_issuer(
  config: TotpConfig,
  issuer: String,
) -> TotpConfig

Sets the issuer for the TOTP configuration. Used for the otpauth URI.

set_last_use

</>

pub fn set_last_use(
  config: TotpConfig,
  last_use: timestamp.Timestamp,
) -> TotpConfig

Sets the last use time for the TOTP configuration. Used to prevent replay attacks.

set_last_use_now

</>

pub fn set_last_use_now(config: TotpConfig) -> TotpConfig

Sets the last use time for the TOTP configuration to the current time.

set_period

</>

pub fn set_period(
  config: TotpConfig,
  period: Int,
) -> Result(TotpConfig, TotpError)

Sets the refresh period in seconds for the TOTP configuration. Must be greater than 0.

set_time

</>

pub fn set_time(
  config: TotpConfig,
  time: timestamp.Timestamp,
) -> TotpConfig

Sets the time for OTP generation. This is only used by totp_from_config. Verification functions use the current time automatically.

set_time_now

</>

pub fn set_time_now(config: TotpConfig) -> TotpConfig

Sets the time for OTP generation to the current time. This is only used by totp_from_config. Verification functions use the current time automatically.

string_to_otp

</>

pub fn string_to_otp(otp: String) -> Result(Otp, TotpError)

Converts a valid OTP string to an OTP type.

totp

</>

pub fn totp(secret: BitArray) -> Result(Otp, TotpError)

Generates a TOTP using the given secret and default configuration. The secret must be at least 16 bytes (128 bits).

totp_from_config

</>

pub fn totp_from_config(config: TotpConfig) -> Otp

Generates a TOTP using the given TOTP configuration. Make sure to set the time with set_time or set_time_now first.