pam_yubico - Man Page
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]
Set the mode of operation, client for OTP validation and challenge-response for challenge-response validation, client is the default.
- authfile=file
Set the 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
Set to your client identity.
- key=key
Set to 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
Set to enable all authentication attempts to succeed (aka 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
The argument 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.
- nullok
If set, 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.
- 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
Specify the path where X509 certificates are stored. This is required if https or ldaps are used in url and ldap_uri respectively.
- proxy=proxy
Specify a 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. E.g. socks5h://user:pass@10.10.0.1:1080
- verbose_otp
This argument is used to show the OTP (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
Specify the LDAP server URI (e.g. ldap://localhost).
- ldap_server=server
Specify the LDAP server host (default LDAP port is used). Deprecated. Use ldap_uri instead.
- ldapdn=dn
The 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.
- 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
An 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 certfile 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/
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/