before this change, we rely on the default-generated fmt::formatter
created from operator<<, but fmt v10 dropped the default-generated
formatter.
in this change, we define a formatter for auth::role_or_anonymous,
and remove their operator<<().
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#16812
in C++20, compiler generate operator!=() if the corresponding
operator==() is already defined, the language now understands
that the comparison is symmetric in the new standard.
fortunately, our operator!=() is always equivalent to
`! operator==()`, this matches the behavior of the default
generated operator!=(). so, in this change, all `operator!=`
are removed.
in addition to the defaulted operator!=, C++20 also brings to us
the defaulted operator==() -- it is able to generated the
operator==() if the member-wise lexicographical comparison.
under some circumstances, this is exactly what we need. so,
in this change, if the operator==() is also implemented as
a lexicographical comparison of all memeber variables of the
class/struct in question, it is implemented using the default
generated one by removing its body and mark the function as
`default`. moreover, if the class happen to have other comparison
operators which are implemented using lexicographical comparison,
the default generated `operator<=>` is used in place of
the defaulted `operator==`.
sometimes, we fail to mark the operator== with the `const`
specifier, in this change, to fulfil the need of C++ standard,
and to be more correct, the `const` specifier is added.
also, to generate the defaulted operator==, the operand should
be `const class_name&`, but it is not always the case, in the
class of `version`, we use `version` as the parameter type, to
fulfill the need of the C++ standard, the parameter type is
changed to `const version&` instead. this does not change
the semantic of the comparison operator. and is a more idiomatic
way to pass non-trivial struct as function parameters.
please note, because in C++20, both operator= and operator<=> are
symmetric, some of the operators in `multiprecision` are removed.
they are the symmetric form of the another variant. if they were
not removed, compiler would, for instance, find ambiguous
overloaded operator '=='.
this change is a cleanup to modernize the code base with C++20
features.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13687
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
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.