There is no constexpr operator+ for std::string_view, so we have to
concatenate the strings ourselves.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
The seastar api v4 changes the return type of when_all_succeed. This
patch adds discard_result when that is best solution to handle the
change.
This doesn't do the actual update to v4 since there are still a few
issues left to fix in seastar. A patch doing just the update will
follow.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Message-Id: <20200617233150.918110-1-espindola@scylladb.com>
All internal execution always uses query text as a key in the
cache of internal prepared statements. There is no need
to publish API for executing an internal prepared statement object.
The folded execute_internal() calls an internal prepare() and then
internal execute().
execute_internal(cache=true) does exactly that.
Before this patch the iterations over migration_notifier::_listeners
could race with listeners being added and removed.
The addition side is not modified, since it is common to add a
listener during construction and it would require a fairly big
refactoring. Instead, the iteration is modified to use indexes instead
of iterators so that it is still valid if another listener is added
concurrently.
For removal we use a rw lock, since removing an element invalidates
indexes too. There are only a few places that needed refactoring to
handle unregister_listener returning a future<>, so this is probably
OK.
Fixes#5541.
Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
Message-Id: <20200120192819.136305-1-espindola@scylladb.com>
This patch breaks one (probably harmless but still) dependency
loop. The query_processor -> migration_manager -> storage_proxy
-> tracing -> query_processor.
The first link is not not needed, as the query_processor needs the
migration_manager purely to (ub)subscribe on notifications.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
The same as with view builder. The constructor still needs both,
but the life-time reference is now for notifier only.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
This patch silences those future discard warnings where it is clear that
discarding the future was actually the intent of the original author,
*and* they did the necessary precautions (handling errors). The patch
also adds some trivial error handling (logging the error) in some
places, which were lacking this, but otherwise look ok. No functional
changes.
When scylla is started for the first time with PasswordAuthenticator
enabled, it can be that a record of the default superuser
will be created in the table with the can_login and is_superuser
set to null. It happens because the module in charge of creating
the row is the role manger and the module in charge of setting the
default password salted hash value is the password authenticator.
Those two modules are started together, it the case when the
password authenticator finish the initialization first, in the
period until the role manager completes it initialization, the row
contains those null columns and any loging attempt in this period
will cause a memory access violation since those columns are not
expected to ever be null. This patch removes the race by starting
the password authenticator and autorizer only after the role manger
finished its initialization.
Tests:
1. Unit tests (release)
2. Auth and cqlsh auth related dtests.
Fixes#4226
Signed-off-by: Eliran Sinvani <eliransin@scylladb.com>
Message-Id: <20190714124839.8392-1-eliransin@scylladb.com>
Replace stdx::optional and stdx::string_view with the C++ std
counterparts.
Some instances of boost::variant were also replaced with std::variant,
namely those that called seastar::visit.
Scylla now requires GCC 8 to compile.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Message-Id: <20190108111141.5369-1-duarte@scylladb.com>
query_processor uses storage_proxy to access data, and the local
database object to access replicated metadata. While it seems strange
that the database object is not used to access data, it is logical
when you consider that a sharded<database> only contain's this node's
data, not the cluster data.
Take advantage of this to replace sharded<database> with a single database
shard.
auth::service already has its own configuration and a function to create it
from db::config; just move it to the caller. This reduces dependencies on the
global db::config class.
sprint() recently became more strict, throwing on sprint("%s", 5). Replace
with the more modern format().
Mechanically converted with https://github.com/avikivity/unsprint.
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.
If `auth::password_authenticator` also creates `system_auth.roles` and
we fix the existence check for the default superuser in
`auth::standard_role_manager` to only search for the columns that it
owns (instead of the column itself), then both modules' initialization
are independent of one another.
Fixes#3319.
When a table, keyspace, or role is created, the creator now is
automatically granted all applicable permissions on the object.
This behavior is consistent with Apache Cassandra.
Fixes#3216.
Instead of some functions in `allow_all_authorizer` throwing exceptions
and others being silently pass-through, we consistently return exception
futures with `auth::unsupported_authorization_operation`. These errors
are converted to `invalid_request_exception` in the CQL error and
ignored where appropriate in the auth subsystem.
This patch came about because of an important (and obvious, in
hindsight) realization: instances of the authorizer, role manager, and
authenticator are clients for access-control state and not the state
itself. This is reflected directly in Scylla: `auth::service` is
sharded across cores and this is possible because each instance queries
and modifies the same global state.
To give more examples, the value of an instance of `std::vector<int>` is
the structure of the container and its contents. The value of `int
file_descriptor` is an identifier for state maintained elsewhere.
Having watched an excellent talk by Herb Sutter [1] and having read an
informative blog post [2], it's clear that a member function marked
`const` communicates that the observable state of the instance is not
modified.
Thus, the member functions of the role-manager, authenticator, and
authorizer clients should not be marked `const` only if the state of the
client itself is observably changed. By this principle, member functions
which do not change the state of the client, but which mutate the global
state the client is associated with (for example, by creating a role)
are marked `const`.
The `start` (and `stop`) functions of the client have the dual role of
initializing (finalizing) both the local client state and the
external state; they are not marked `const`.
[1] https://herbsutter.com/2013/01/01/video-you-dont-know-const-and-mutable/
[2] http://talesofcpp.fusionfenix.com/post-2/episode-one-to-be-or-not-to-be-const
Previously, when a table or keyspace was dropped, the
authorizer (through a `migration_listener`) automatically dropped all
permissions granted on that resource.
Likewise, when a role is granted permissions and the role is dropped,
all permissions granted to the role are dropped.
In this change, we now treat role resources just like table and keyspace
resources: if a permission is granted on a role (like "GRANT AUTHORIZE
ON ROLE qa TO phil") and the "qa" role is dropped, then all permissions
on the "qa" role resource are also dropped.
auth: Decouple authorization and role management
Access control in Scylla consists of three main modules: authentication,
authorization, and role-management.
Each of these modules is intended to be interchangeable with alternative
implementations. The `auth::service` class composes these modules
together to perform all access-control functionality, including caching.
This architecture implies two main properties of the individual
access-control modules:
- Independence of modules. An implementation of authentication should
have no dependence or knowledge of authorization or role-management,
for example.
- Simplicity of implementing the interface. Functionality that is common
to all implementations should not have to be duplicated in each
implementation. The abstract interface for a module should capture
only the differences between particular implementations.
Previously, the authorization interface depended on an instance of
`auth::service` for certain operations, since it required aggregation
over all the roles granted to a particular role or required checking if
a given role had superuser.
This change decouples authorization entirely from role-management: the
authorizer now manages only permissions granted directly to a role, and
not those inherited through other roles.
When a query needs to be authorized, `auth::service::get_permissions`
first uses the role manager to check if the role has superuser. Then, it
aggregates calls to `auth::authorizer::authorize` for each role granted
to the role (again, from the role-manager) to determine the sum-total
permission set. This information is cached for future queries.
This structure allows for easier error handling and
management (something I hope to improve in the future for both the
authorizer and authenticator interfaces), easier system testing, easier
implementation of the abstract interfaces, and clearer system
boundaries (so the code is easier to grok).
Some authorizers, like the "TransitionalAuthorizer", grant permissions
to anonymous users. Therefore, we could not unconditionally authorize an
empty permission set in `auth::service` for anonymous users. To account
for this, the interface of the authorizer has changed to accept an
optional name in `authorize`.
One additional notable change to the authorizer is the
`auth::authorizer::list`: previously, the filtering happened at the CQL
query layer and depended on the roles granted to the role in question.
I've changed the function to simply query for all roles and I do the
filtering in `auth::system` in-memory with the STL. This was necessary
to allow the authorizer to be decoupled from role-management. This
function is only called for LIST PERMISSIONS (so performance is not a
concern), and it significantly reduces demand on the implementation.
Finally, we unconditionally create a user in `cql_test_env` since
authorization requires its existence.
Previously, a "data" auth. resource knew how to check it's own existence by
accessing a global variable.
This patch accomplishes two things: it adds existence checking to all
kinds of resources, and moves these checks outside of `auth::resource`
itself and into `auth::service` (so that global variables are no longer
accessed).
This has the dual benefit of not enforcing copying on implementations of
the abstract interface and also limiting unnecessary copies.
As usual with Seastar, we follow the convention that a reference
parameter to a function is assumed valid for the duration of the
`future` that is returned. `do_with` helps here.
By adding some constants for root resources, we can avoid using
`seastar::do_with` at some call-sites involving `resource` instances.
While it's undefined behavior to pass an unsupported option to a
specific authenticator directly, the `auth::service` layer will check
options and throw this exception. It is turned into a
`invalid_request_exception` by the CQL layer.
The motivation behind this change is the idea that constructing a new
instance of an object is the job of the constructor.
One big benefit of this structure (with the addition of helpers for
convenience) is that calls for emplacing instances (like
`std::make_shared`, or `std::vector::emplace_back`) work without any
difficulty. This would not be true for static construction functions.
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 previous code has an off-by-one error since the iterator is
incremented unconditionally prior to being compared to the end of the
collection.
This new version is also shorter thanks to `seastar::do_until`.
The components of access-control (authentication, authorization, and
role-management) are designed as abstract interfaces, but due to
decisions of Apache Cassandra, certain implementations are dependent on
other particular implementations.
This change throws a new exception,
`auth::incompatible_module_combination`, when a dependency is not
satisfied.
delayed_tasks has a bug that if the object is destroyed while a timer
callback is queued, the callback will then try to access freed memory.
This could be fixed by providing a stop() function that waits for
pending callbacks, but we can just replace the whole thing by levering
the abort_source-enabled exponential_backoff_retry.
Instead of a single sharded service shared all by all instances of
`auth::service`, it makes more sense for each instance of
`auth::service` to own its own instance of the permissions cache.
While it just calls into the underlying role manager, this level of
indirection allows us to add a roles cache in the future (which is
consistent with the behavior of Apache Cassandra).
This functionality is useful for implementing CQL statements and will
replace `auth::is_super_user` once roles have replaced users in Scylla.
Since eventually the auth service will have a roles cache, this function
is here rather than a part `role_manager`.
