Remove implicit timeouts and replace with caller-specified timeouts.
This allows removing the ambiguity about what timeout a statement is
executed with, and allows removing cql_statement::execute_internal(),
which mostly overrode timeouts and consistency levels.
Timeout selection is now as follows:
query_processor::*_internal: infinite timeout, CL=ONE
query_processor::process(), execute(): user-specified consisistency level and timeout
All callers were adjusted to specify an infinite timeout. This can be
further adjusted later to use the "other" timeout for DCL and the
read or write timeout (as needed) for authentication in the normal
query path.
Note that infinite timeouts don't mean that the query will hang; as
soon as the failure detector decides that the node is down, RPC
responses will termiante with a failure and the query will fail.
All we require are value semantics.
`client_state` still stores `authenticated_user` in a `shared_ptr`, but
the behavior of that class is complex enough to warrant its own
discussion/design/refactor.
The most important change is replacing `auth::authenticated_user::name`
with a public `std::optional<sstring>` member. Anonymous users have no
name. This replaces the insecure and bug-prone special-string of
"anonymous" for anonymous users, which does unfortunate things with the
authorizer.
The new `auth::is_anonymous` function exists for convenience since
checking the absence of a `std::optional` value can be tedious.
When a caller really wants a name unconditionally, a new stream output
function is also available.
This is a large change, but it's a necessary evil.
This change brings us to a minimally-functional implementation of roles.
There are many additional changes that are necessary, including refined
grammar, bug fixes, code hygiene, and internal code structure changes.
In the interest of keeping this patch somewhat read-able, those changes
will come in subsequent patches. Until that time, roles are still marked
"unimplemented".
IMPORTANT: This code does not include any mechanism for transitioning a
cluster from user-based access-control to role-based access control. All
existing access-control metadata will be ignored (though not deleted).
Specific changes:
- All user-specific CQL statements now delegate to their roles
equivalent. The statements are effectively the same, but CREATE USER
will include LOGIN automatically. Also, LIST USERS only lists roles
with LOGIN.
- A call to LIST PERMISSIONS will now also list permissions of roles
that have been granted to the caller, in addition to permissions which
have been granted directly.
- Much of the logic of creating, altering, and deleting roles has been
moved to `auth::service`, since these operations require cooperation
between the authenticator, authorizer, and role-manager.
- LIST USERS actually works as expected now (fixes#2968).
The set of allowed options is quite small, so we benefit from a static
representation (member variables) over a dynamic map.
We also logically move the "OPTIONS" option to the domain of the
authenticator (from user management), since this is where it is applied.
This refactor also aims to reduce compilation time by moving
`authentication_options` into its own header file.
While changes to `user_options` were necessary to accommodate the new
structure, that class will be deprecated shortly in the switch to roles.
Therefore, the changes are strictly temporary.
This change generalizes the implementation of a `resource` to many
different kinds of resources, though there is still only one
kind (`data`). In the future, we also expect resource kinds for roles,
user-defined functions (UDFs), and possibly on particular REST
end-points.
I considered several approaches to generalizing to different kinds of
resources.
One approach is to have a base class that is inherited from by different
resource kinds. The common functionality would be accessed through
virtual member functions and kind-specific functions would exist in
sub-classes. I rejected this approach because dealing with different
kinds of resources uniformly requires storage and life-time management
through something like `std::unique_ptr<auth::resource>`, which means
that we lose value semantics (including comparison) and must deal with
complications around ownership.
Another option was to use `boost::variant` (or, in future,
`std::variant`). This is closer to what we want, since there a static
set of resource kinds that we support. I rejected this approach for two
reasons. The first is that all resource kinds share the same data (a
list of segments and a root identifier), which would be duplicated in
each type that composed the variant. The second is that the complexity
and source-code overhead of `boost::variant` didn't seem warranted.
The solution I ended up with is home-grown variant. All resources are
described in the same `final` class: `auth::resource`. This class has
value semantics, supports equality comparison, and has a strict
ordering. All resources have in common a tag ("kind") and a list of
parts. Most operations on resources don't care about the kind of
resource (like getting its name, parsing a name, querying for the
parent, etc). These are just member functions of the class.
When we care about a kind-specific interpretation of a resource, we can
produce a "view" of the resource. For example, `data_resource_view`
allows for accessing the (optional) keyspace and table names.
I anticipate in the future to add functions for creating role
resources (`auth::resource::role`) and also `role_resource_view`.
The functional behaviour of the system should be unchanged with this
patch.
I've added new unit tests in `auth_resource_test.cc` and removed the old
test from `auth_test.cc`.
Fixes#3027.
This change appears quite large, but is logically fairly simple.
Previously, the `auth` module was structured around global state in a
number of ways:
- There existed global instances for the authenticator and the
authorizer, which were accessed pervasively throughout the system
through `auth::authenticator::get()` and `auth::authorizer::get()`,
respectively. These instances needed to be initialized before they
could be used with `auth::authenticator::setup(sstring type_name)`
and `auth::authorizer::setup(sstring type_name)`.
- The implementation of the `auth::auth` functions and the authenticator
and authorizer depended on resources accessed globally through
`cql3::get_local_query_processor()` and
`service::get_local_migration_manager()`.
- CQL statements would check for access and manage users through static
functions in `auth::auth`. These functions would access the global
authenticator and authorizer instances and depended on the necessary
systems being started before they were used.
This change eliminates global state from all of these.
The specific changes are:
- Move out `allow_all_authenticator` and `allow_all_authorizer` into
their own files so that they're constructed like any other
authenticator or authorizer.
- Delete `auth.hh` and `auth.cc`. Constants and helper functions useful
for implementing functionality in the `auth` module have moved to
`common.hh`.
- Remove silent global dependency in
`auth::authenticated_user::is_super()` on the auth* service in favour
of a new function `auth::is_super_user()` with an explicit auth*
service argument.
- Remove global authenticator and authorizer instances, as well as the
`setup()` functions.
- Expose dependency on the auth* service in
`auth::authorizer::authorize()` and `auth::authorizer::list()`, which
is necessary to check for superuser status.
- Add an explicit `service::migration_manager` argument to the
authenticators and authorizers so they can announce metadata tables.
- The permissions cache now requires an auth* service reference instead
of just an authorizer since authorizing also requires this.
- The permissions cache configuration can now easily be created from the
DB configuration.
- Move the static functions in `auth::auth` to the new `auth::service`.
Where possible, previously static resources like the `delayed_tasks`
are now members.
- Validating `cql3::user_options` requires an authenticator, which was
previously accessed globally.
- Instances of the auth* service are accessed through `external`
instances of `client_state` instead of globally. This includes several
CQL statements including `alter_user_statement`,
`create_user_statement`, `drop_user_statement`, `grant_statement`,
`list_permissions_statement`, `permissions_altering_statement`, and
`revoke_statement`. For `internal` `client_state`, this is `nullptr`.
- Since the `cql_server` is responsible for instantiating connections
and each connection gets a new `client_state`, the `cql_server` is
instantiated with a reference to the auth* service.
- Similarly, the Thrift server is now also instantiated with a reference
to the auth* service.
- Since the storage service is responsible for instantiating and
starting the sharded servers, it is instantiated with the sharded
auth* service which it threads through. All relevant factory functions
have been updated.
- The storage service is still responsible for starting the auth*
service it has been provided, and shutting it down.
- The `cql_test_env` is now instantiated with an instance of the auth*
service, and can be accessed through a member function.
- All unit tests have been updated and pass.
Fixes#2929.
Using "Meyer's singletons" eliminate the problem of static constant
initialization order because static variables inside functions are
initialized only the first time control flow passes over their
declaration.
Fixes#2966.
test_cassandra_hash also sort of expects exceptions. ASas causes false
positives here as well with seastar::thread, so do it with normal cont.
Message-Id: <1453295521-29580-2-git-send-email-calle@scylladb.com>
test_password_authenticator_operations causes ASan failures, in a way
that I am 99% sure is fully false positive, caused by a combo of
seastar threads, exception throwing and externals.
In lieu of actually identifying what ASan flaw causes this and
potentially cure it, for now, lets just re-write the test in question
to not use seastar::async, but normal continuation. Less easy to read,
but passes ASan.
Message-Id: <1453205136-10308-1-git-send-email-calle@scylladb.com>
