RGW Support for Multifactor Authentication
New in version Mimic.
The S3 multifactor authentication (MFA) feature allows users to require the use of one-time password when removing objects on certain buckets. The buckets need to be configured with versioning and MFA enabled which can be done through the S3 api.
Time-based one time password tokens can be assigned to a user through radosgw-admin. Each token has a secret seed, and a serial id that is assigned to it. Tokens are added to the user, can be listed, removed, and can also be re-synchronized.
Multisite
While the MFA IDs are set on the user’s metadata, the actual MFA one time password configuration resides in the local zone’s osds. Therefore, in a multi-site environment it is advisable to use different tokens for different zones.
Terminology
-TOTP
: Time-based One Time Password
-token serial
: a string that represents the ID of a TOTP token
-token seed
: the secret seed that is used to calculate the TOTP
-totp seconds
: the time resolution that is being used for TOTP generation
-totp window
: the number of TOTP tokens that are checked before and after the current token when validating token
-totp pin
: the valid value of a TOTP token at a certain time
Admin commands
Create a new MFA TOTP token
# radosgw-admin mfa create --uid=<user-id> \
--totp-serial=<serial> \
--totp-seed=<seed> \
[ --totp-seed-type=<hex|base32> ] \
[ --totp-seconds=<num-seconds> ] \
[ --totp-window=<twindow> ]
List MFA TOTP tokens
# radosgw-admin mfa list --uid=<user-id>
Show MFA TOTP token
# radosgw-admin mfa get --uid=<user-id> --totp-serial=<serial>
Delete MFA TOTP token
# radosgw-admin mfa remove --uid=<user-id> --totp-serial=<serial>
Check MFA TOTP token
Test a TOTP token pin, needed for validating that TOTP functions correctly.
# radosgw-admin mfa check --uid=<user-id> --totp-serial=<serial> \
--totp-pin=<pin>
Re-sync MFA TOTP token
In order to re-sync the TOTP token (in case of time skew). This requires feeding two consecutive pins: the previous pin, and the current pin.
# radosgw-admin mfa resync --uid=<user-id> --totp-serial=<serial> \
--totp-pin=<prev-pin> --totp=pin=<current-pin>