PAM_YUBICO(8)

NAME
pam_yubico - Module for YubiKey authentication

SYNOPSIS

pam_yubico [...]

DESCRIPTION

The module is for authentication of YubiKeys, either with online validation of OTP, or offline validation with HMAC-SHA1 challenge-response.

OPTIONS

debug
    Turns on debugging.

debug_file=file
    File name to write debug to, the file must exist and be a regular file. Defaults to stdout.

mode=[client|challenge-response]
    Mode of operation, client for OTP validation and challenge-response for challenge-response validation. Defaults to client.

authfile=file
    Location of the file that holds the mappings of YubiKey token IDs to user names. The format is username:first_public_id:second_public_id:... Default location of the file is $HOME/.yubico/authorized_yubikeys.

id=id
    Your API client identity for the validation server.

key=key
    Your client key in base64 format. The client key is also known as API key, and provides integrity in the communication between the client (you) and the validation server. If you want to get one for use with the default YubiCloud service, please go to: https://upgrade.yubico.com/getapikey/

alwaysok
    Succeed with all authentication attempts (dangerous, presentation mode).

try_first_pass
    Before prompting the user for their password, the module first tries the previous stacked module´s password in case that satisfies this module as well.

use_first_pass
    Forces the module to use a previous stacked modules password and will never prompt the user - if no password is available or the password is not appropriate, the user will be denied access.

always_prompt
    If set, don’t attempt to do a lookup to determine if the user has a YubiKey configured but instead prompt for one no matter what. This is useful in the case where ldap_bind_as_user is enabled but this module is being used to read the user’s password (in a YubiKey+OTP auth scenario).

nullok
    Don’t fail when there are no tokens declared for the user in the authorization mapping files or in LDAP. This can be used to make YubiKey authentication optional unless the user has associated tokens.

ldap_starttls
    If set, issue a STARTTLS command to the LDAP connection before attempting to bind to it. This is a common setup for servers that only listen on port 389 but still require TLS.

ldap_bind_as_user
    Use the user logging in to bind to ldap. This will use the password provided by the user via PAM. If this is set, ldapdn and uid_attr must also be set. Enabling this will cause ldap_bind_user and ldap_bind_password to be ignored.

urllist=list
    List of URL templates to be used. This is set by calling ykclient_set_url_bases. The list should be in the format: https://api1.example.com/wsapi/2.0/verify;https://api2.example.com/wsapi/2.0/verify

url=url
    This option should not be used, please use the urllist option instead. Set the URL template to use, this is set by calling ykclient_set_url_template. The URL should be set in the format https://api.example.com/wsapi/2.0/verify?id=%d&otp=%s

capath=path
    The path where X509 certificates are stored. This is required if https or ldaps are used in url and ldap_uri, respectively.

cainfo=file
    Option to allow for usage of a CA bundle instead of path.

proxy=proxy
    The proxy to connect to the validation server. Valid schemes are http://, https://, socks4://, socks4a://, socks5:// or socks5h://. Socks5h asks the proxy to do the DNS resolving. If no scheme or port is specified HTTP proxy port 1080 will be used. Example: socks5h://user:pass@10.10.0.1:1080

verbose_otp
    Show the One-Time Password when it is entered, i.e. to enable terminal echo of entered characters. You are advised to not use this, if you are using two factor authentication because that will display your password on the screen. This requires the service using the PAM module to display custom fields. This option can not be used with OpenSSH.

ldap_uri=uri
    The LDAP server URI (e.g. ldap://localhost).

ldap_server=server
    The LDAP server host (default LDAP port is used). Deprecated. Use ldap_uri instead.

ldapdn=dn
    The distinguished name (DN) where the users are stored (eg: ou=users,dc=domain,dc=com). If ldap_filter is used this is the base from which the subtree search will be performed.

ldap_clientcertfile=clientcertfile
    The path to a client cert file to use when talking to the LDAP server. Note this requires ldap_clientkeyfile to be set as well.

ldap_clientkeyfile=clientkeyfile
    The path to a key to be used with the client cert when talking to the LDAP server. Note this requires ldap_clientcertfile to be set as well.

user_attr=attr
    The LDAP attribute used to store user names (eg:cn).

yubi_attr=attr
    The LDAP attribute used to store the YubiKey ID.

yubi_attr_prefix=prefix
    The prefix of the LDAP attribute’s value, in case of a generic attribute, used to store several types of IDs.

token_id_length=length
    Length of ID prefixing the OTP (this is 12 if using the YubiCloud).

ldap_bind_user=user
    The user to attempt a LDAP bind as.

ldap_bind_password=password
    The password to use on LDAP bind.

ldap_filter=filter
    A LDAP filter to use for attempting to find the correct object in LDAP. In this string %u will be replaced with the username.

ldap_cacertfile=cacertfile
    CA certitificate file for the LDAP connection.

chalresp_path=path
    Path of a system-wide directory where challenge-response files can be found for users. Default location is $HOME/.yubico/.

mysql_server=mysqlserver
    Hostname/Adress of mysql server. Example 10.0.0.1

mysql_port=mysqlport
    Network port of mysql server.

mysql_user=mysqluser
    User for accessing to the database. Strongly recommended to use a specific user with read only access.

mysql_password=mysqlpassword
    Mysql password associated to the user.

mysql_database=mysqldatabase
    the name of the database. Example : otp

EXAMPLES

    auth sufficient pam_yubico.so id=16 debug

    auth required pam_yubico.so mode=challenge-response

    auth required pam_yubico.so id=16 ldap_uri=ldaps://ldap.example.com ldap_filter=(uid=%u) yubi_attr=yubiKeyId

FILES

$HOME/.yubico/authorized_yubikeys
    If authfile is not set, this file is used for the mapping between YubiKey public ID and in client mode.

$HOME/.yubico/challenge, $HOME/.yubico/challenge-serial_number
    If chalresp_path is not set, these files are used to hold next challenge and expected response for the user in challenge-response mode. If chalresp_path is set the filename will be username instead of challenge.

BUGS

Report yubico-pam bugs in the issue tracker: https://github.com/Yubico/yubico-pam/issues

SEE ALSO

ykpamcfg(1), pam(7)

The yubico-pam home page: https://developers.yubico.com/yubico-pam/

YubiKeys can be obtained from Yubico: http://www.yubico.com/