View Source VintageNetWiFi.WPA2 (vintage_net_wifi v0.12.6)

WPA2 preshared key calculations

WPA2 doesn't use passphrases directly, but instead hashes them with the SSID and uses the result for the network key. The algorithm that runs the hash takes some time so it's useful to compute the PSK from the passphrase once rather than specifying it each time.

Summary

Functions

Convert a WiFi WPA2 passphrase into a PSK

Validate the length and characters of a passphrase

Validate the length of the SSID

Types

invalid_passphrase_error()

@type invalid_passphrase_error() ::
  :password_too_short | :password_too_long | :invalid_characters

invalid_ssid_error()

@type invalid_ssid_error() :: :ssid_too_short | :ssid_too_long

psk()

@type psk() :: <<_::512>>

A WPA2 preshared key

Functions

to_psk(ssid, psk)

@spec to_psk(String.t(), psk() | String.t()) ::
  {:ok, psk()} | {:error, invalid_ssid_error() | invalid_passphrase_error()}

Convert a WiFi WPA2 passphrase into a PSK

If a passphrase looks like a PSK, then it's assumed that it already is a PSK and is passed through.

See IEEE Std 802.11i-2004 Appendix H.4 for the algorithm.

validate_passphrase(password)

@spec validate_passphrase(String.t()) :: :ok | {:error, invalid_passphrase_error()}

Validate the length and characters of a passphrase

A valid passphrase is between 8 and 63 characters long, and only contains ASCII characters (values between 32 and 126, inclusive).

validate_ssid(ssid)

@spec validate_ssid(String.t()) :: :ok | {:error, invalid_ssid_error()}

Validate the length of the SSID

A valid SSID is between 1 and 32 characters long.