How to use the command 'wpa_passphrase' (with examples)

The wpa_passphrase command is used to generate a WPA-PSK key from an ASCII passphrase for a given SSID (Service Set Identifier). This command is useful when setting up a Wi-Fi network that requires a pre-shared key for authentication.

Use case 1: Compute and display the WPA-PSK key from stdin

Code:

wpa_passphrase SSID

Motivation:

In certain scenarios, you may want to read the passphrase from stdin instead of providing it as a command line argument. This use case allows you to enter the passphrase interactively, enhancing security by not exposing it in the command history.

Explanation:

• SSID: The SSID (Service Set Identifier) of the wireless network that you want to generate the WPA-PSK key for.

Example output:

If we execute the command wpa_passphrase MyWiFi, the program will prompt us to enter the passphrase. Let’s say we enter “MyPassphrase”. The output will be:

network={
    ssid="MyWiFi"
    #psk="MyPassphrase"
    psk=7b66a7e4c01df0efde68fbe5841052e">

}

In this example, the generated WPA-PSK key for the SSID “MyWiFi” and passphrase “MyPassphrase” is “7b66a7e4c01df0efde68fbe5841052e”.

Use case 2: Compute and display the WPA-PSK key by specifying the passphrase as an argument

Code:

wpa_passphrase SSID passphrase

Motivation:

Sometimes, it is convenient to provide the passphrase as a command line argument instead of entering it interactively. This use case allows you to generate the WPA-PSK key with minimal manual input.

Explanation:

• SSID: The SSID (Service Set Identifier) of the wireless network that you want to generate the WPA-PSK key for.
• passphrase: The ASCII passphrase that will be used to generate the WPA-PSK key.

Example output:

If we run the command wpa_passphrase MyWiFi MyPassphrase, the program will generate and display the WPA-PSK key for the provided SSID and passphrase. The output will be:

network={
    ssid="MyWiFi"
    #psk="MyPassphrase"
    psk=7b66a7e4c01df0efde68fbe5841052e">

}

In this example, the generated WPA-PSK key for the SSID “MyWiFi” and passphrase “MyPassphrase” is “7b66a7e4c01df0efde68fbe5841052e”.

Conclusion:

The wpa_passphrase command is a handy tool for generating WPA-PSK keys from ASCII passphrases for Wi-Fi networks. It provides flexibility by allowing you to enter the passphrase interactively or specify it as a command line argument. This command greatly simplifies the process of setting up secure Wi-Fi networks with pre-shared keys.