fix: authenticate LDAP via actual DN instead of normalized DN
Normalized DN is only for internal representation, not for
external communication, any communication to LDAP must be
based on actual user DN. LDAP servers do not understand
normalized DN.
fixes#19757
This change uses the updated ldap library in minio/pkg (bumped
up to v3). A new config parameter is added for LDAP configuration to
specify extra user attributes to load from the LDAP server and to store
them as additional claims for the user.
A test is added in sts_handlers.go that shows how to access the LDAP
attributes as a claim.
This is in preparation for adding SSH pubkey authentication to MinIO's SFTP
integration.
When importing access keys (i.e. service accounts) for LDAP accounts,
we are requiring groups to exist under one of the configured group base
DNs. This is not correct. This change fixes this by only checking for
existence and storing the normalized form of the group DN - we do not
return an error if the group is not under a base DN.
Test is updated to illustrate an import failure that would happen
without this change.
This fixes a regression from #19358 which prevents policy mappings
created in the latest release from being displayed in policy entity
listing APIs.
This is due to the possibility that the base DNs in the LDAP config are
not in a normalized form and #19358 introduced normalized of mapping
keys (user DNs and group DNs). When listing, we check if the policy
mappings are on entities that parse as valid DNs that are descendants of
the base DNs in the config.
Test added that demonstrates a failure without this fix.
Create new code paths for multiple subsystems in the code. This will
make maintaing this easier later.
Also introduce bugLogIf() for errors that should not happen in the first
place.
Instead of relying on user input values, we use the DN value returned by
the LDAP server.
This handles cases like when a mapping is set on a DN value
`uid=svc.algorithm,OU=swengg,DC=min,DC=io` with a user input value (with
unicode variation) of `uid=svc﹒algorithm,OU=swengg,DC=min,DC=io`. The
LDAP server on lookup of this DN returns the normalized value where the
unicode dot character `SMALL FULL STOP` (in the user input), gets
replaced with regular full stop.
A new middleware function is added for admin handlers, including options
for modifying certain behaviors. This admin middleware:
- sets the handler context via reflection in the request and sends AuditLog
- checks for object API availability (skipping it if a flag is passed)
- enables gzip compression (skipping it if a flag is passed)
- enables header tracing (adding body tracing if a flag is passed)
While the new function is a middleware, due to the flags used for
conditional behavior modification, which is used in each route registration
call.
To try to ensure that no regressions are introduced, the following
changes were done mechanically mostly with `sed` and regexp:
- Remove defer logger.AuditLog in admin handlers
- Replace newContext() calls with r.Context()
- Update admin routes registration calls
Bonus: remove unused NetSpeedtestHandler
Since the new adminMiddleware function checks for object layer presence
by default, we need to pass the `noObjLayerFlag` explicitly to admin
handlers that should work even when it is not available. The following
admin handlers do not require it:
- ServerInfoHandler
- StartProfilingHandler
- DownloadProfilingHandler
- ProfileHandler
- SiteReplicationDevNull
- SiteReplicationNetPerf
- TraceHandler
For these handlers adminMiddleware does not check for the object layer
presence (disabled by passing the `noObjLayerFlag`), and for all other
handlers, the pre-check ensures that the handler is not called when the
object layer is not available - the client would get a
ErrServerNotInitialized and can retry later.
This `noObjLayerFlag` is added based on existing behavior for these
handlers only.
For policy attach/detach API to work correctly the server should hold a
lock before reading existing policy mapping and until after writing the
updated policy mapping. This is fixed in this change.
A site replication bug, where LDAP policy attach/detach were not
correctly propagated is also fixed in this change.
Bonus: Additionally, the server responds with the actual (or net)
changes performed in the attach/detach API call. For e.g. if a user
already has policy A applied, and a call to attach policies A and B is
performed, the server will respond that B was attached successfully.
