NAME¶

ykpersonalize - personalize YubiKey OTP tokens

SYNOPSIS¶

ykpersonalize [ -1 | -2] [-sfile] [-ifile] [-axxx] [-cxxx] [-ooption] [ -y] [-v] [-h] [ -n] [-t] [-u] [-x]

OPTIONS¶

Set the AES key, user ID and other settings in a YubiKey. For the complete explanation of the meaning of all parameters, see the reference manual: YubiKey manual ⟨URL: http://yubico.com/files/YubiKey_manual-2.0.pdf ⟩

-1

change the first configuration. This is the default and is normally used for true OTP generation. In this configuration, TKTFLAG_APPEND_CR is set by default.

-2

change the second configuration. This is for YubiKey II only and is then normally used for static key generation. In this configuration, TKTFLAG_APPEND_CR, CFGFLAG_STATIC_TICKET, CFGFLAG_STRONG_PW1, CFGFLAG_STRONG_PW2 and CFGFLAG_MAN_UPDATE are set by default.

-sfile

save configuration to file instead of key. (if file is -, send to stdout)

-ifile

read configuration from file. (if file is -, read from stdin)

-axxx

A 32 char (40 for OATH-HOTP and HMAC challenge-response) hex value (not modhex) of a fixed AES key to use.

-cxxx

A 12 char hex value (not modhex) to use as access code for programming. NOTE: this does NOT SET the access code, that's done with -oaccess =.

-ooption

change configuration option. Possible option arguments are

-y

always commit without prompting

-v

Be more verbose

-h

Help

YubiKey NEO only

YubiKey 2.3 and above

Ticket flags¶

[-]tab-first

Send a tab character as the first character. This is usually used to move to the next input field.

[-]append-tab1

Send a tab character between the fixed part and the one-time password part. This is useful if you have the fixed portion equal to the user name and two input fields that you navigate between using tab.

[-]append-tab2

Send a tab character as the last character.

[-]append-delay1

Add a half-second delay before sending the one-time password part.

[-]append-delay2

Add a half-second delay after sending the one-time password part.

[-]append-cr

Send a carriage return after sending the one-time password part.

YubiKey 2.0 firmware and above

[-]protect-cfg2

When written to configuration 1, block later updates to configuration 2. When written to configuration 2, prevent configuration 1 from having the lock bit set.

YubiKey 2.1 firmware and above

[-]oath-hotp

Set OATH-HOTP mode rather than YubiKey mode. In this mode, the token functions according to the OATH-HOTP standard.

YubiKey 2.2 firmware and above

[-]chal-resp

Set challenge-response mode.

Configuration flags¶

[-] send-ref Send a reference string of all 16 modhex characters before the fixed part. This can not be combined with the strong-pw2 flag.

[-]pacing-10ms

Add a 10ms delay between key presses.

[-]pacing-20ms

Add a 20ms delay between key presses.

[-]static-ticket

Output a fixed string rather than a one-time password. The password is still based on the AES key and should be hard to guess and impossible to remember.

YubiKey 1.x firmware only

[-]ticket-first

Send the one-time password rather than the fixed part first.

[-]allow-hidtrig

Allow trigger through HID/keyboard by pressing caps-, num or scroll-lock twice. Not recommended for security reasons.

YubiKey 2.0 firmware and above

[-]short-ticket

Limit the length of the static string to max 16 digits. This flag only makes sense with the -ostatic-ticket option.

[-]strong-pw1

Upper-case the two first letters of the output string. This is for compatibility with legacy systems that enforce both uppercase and lowercase characters in a password and does not add any security.

[-]strong-pw2

Replace the first eight characters of the modhex alphabet with the numbers 0 to 7. Like strong-pw1, this is intended to support legacy systems.

[-]man-update

Enable user-initiated update of the static password. Only makes sense with the -ostatic-ticket option.

YubiKey 2.1 firmware and above

[-]oath-hotp8

When set, generate an 8-digit HOTP rather than a 6-digit one.

[-]oath-fixed-modhex1

When set, the first byte of the fixed part is sent as modhex.

[-]oath-fixed-modhex2

When set, the first two bytes of the fixed part is sent as modhex.

[-]oath-fixed-modhex

When set, the fixed part is sent as modhex.

oath-id=m:OOTTUUUUUUUU

Configure OATH token id with a provided value. See description of this option under the 2.2 section for details, but note that a YubiKey 2.1 key can't report it's serial number and thus a token identifier value must be specified.

YubiKey 2.2 firmware and above

[-]chal-yubico

Yubico OTP challenge-response mode.

[-]chal-hmac

Generate HMAC-SHA1 challenge responses.

[-]hmac-lt64

Calculate HMAC on less than 64 bytes input. Whatever is in the last byte of the challenge is used as end of input marker (backtracking from end of payload).

[-]chal-btn-trig

The YubiKey will wait for the user to press the key (within 15 seconds) before answering the challenge.

[-]serial-btn-visible

The YubiKey will emit it's serial number if the button is pressed during power-up.

[-]serial-usb-visible

The YubiKey will indicate it's serial number in the USB iSerial field.

[-]serial-api-visible

The YubiKey will allow it's serial number to be read using an API call.

oath-id[=m:OOTTUUUUUUUU]

Configure OATH token id with a provided value, or if used without a value use the standard YubiKey token identifier.

 

The standard OATH token id for a Yubico YubiKey is (modhex) OO=ub, TT=he, (decimal) UUUUUUUU=serial number.

 

The reason for the decimal serial number is to make it easy for humans to correlate the serial number on the back of the YubiKey to an entry in a list of associated tokens for example. Other encodings can be accomplished using the appropriate oath-fixed-modhex options.

 

Note that the YubiKey must be programmed to allow reading it's serial number, otherwise automatic token id creation is not possible.

 

See section "5.3.4 - OATH-HOTP Token Identifier" of the YubiKey manual ⟨URL: http://yubico.com/files/YubiKey_manual-2.0.pdf ⟩ for further details.

YubiKey 2.3 firmware and above

[-]use-numeric-keypad

Send scancodes for numeric keypad keypresses when sending digits - helps with some keyboard layouts.

[-]fast-trig

Faster triggering when only configuration 1 is available.

[-]allow-update

Allow updating of certain parameters in a configuration at a later time.

[-]dormant

Hides/unhides a configuration stored in a YubiKey.

 

OATH-HOTP Mode¶

When using OATH-HOTP mode, a HMAC key of 160 bits (20 bytes, 40 chars of hex) can be supplied with -a.

Challenge-response Mode¶

In CHAL-RESP mode, the token will NOT generate any keypresses when the button is pressed (although it is perfectly possible to have one slot with a keypress-generating configuration, and the other in challenge-response mode). Instead, a program capable of sending USB HID feature reports to the token must be used to send it a challenge, and read the response.

Modhex¶

Modhex is a way of writing hex digits where the “digits” are chosen for being in the same place on most keyboard layouts.

To convert from hex to modhex, you can use

To convert the other way, use

BUGS¶

Report ykpersonalize bugs in the issue tracker ⟨URL: https://github.com/Yubico/yubikey-personalization/issues ⟩

SEE ALSO¶

The ykpersonalize home page ⟨URL: http://code.google.com/p/yubikey-personalization/ ⟩ YubiKeys can be obtained from Yubico ⟨URL: http://www.yubico.com/ ⟩.