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Alternator already supports **authentication** - the ability to to sign each request as a particular user. The users that can be used are the different "roles" that are created by CQL "CREATE ROLE" commands. This series adds support for **authorization**, i.e., the ability to determine that only some of these roles are allowed to read or write particular tables, to create new tables, and so on. The way we chose to do this in this series is to support CQL's existing role-based access control (RBAC) commands - GRANT and REVOKE - on Alternator tables. For example, an Alternator table "xyz" is visible to CQL as "alternator_xyz.xyz", so a `GRANT SELECT ON alternator_xyz.xyz TO myrole` will allow read commands (e.g., GetItem) on that table, and without this GRANT, a GetItem will fail with `AccessDeniedException`. This series adds the necessary checks to all relevant Alternator operations, and also adds extensive functional testing for this feature - i.e., that certain DynamoDB API operations are not allowed without the appropriate GRANTs. The following permissions are needed for the following Alternator API operations: * **SELECT**: `GetItem`, `Query`, `Scan`, `BatchGetItem`, `GetRecords` * **MODIFY**: `PutItem`, `DeleteItem`, `UpdateItem`, `BatchWriteItem` * **CREATE**: `CreateTable` * **DROP**: `DeleteTable` * **ALTER**: `UpdateTable`, `TagResource`, `UntagResource`, `UpdateTimeToLive` * _none needed_: `ListTables`, `DescribeTable`, `DescribeEndpoints`, `ListTagsOfResource`, `DescribeTimeToLive`, `DescribeContinuousBackups`, `ListStreams`, `DescribeStream`, `GetShardIterator` Currently, I decided that for consistency each operation requires one permission only. For example, PutItem only requires MODIFY permission. This is despite the fact that in some cases (namely, `ReturnValues=ALL_OLD`) it can also _read_ the item. We should perhaps discuss this decision - and compare how it was done in CQL - e.g., what happens in LWT writes that may return old values? Different permissions can be granted for a base table, each of its views, and the CDC table (Alternator streams). This adds power - e.g., we can allow a role to read only a view but not the base table, or read the table but not its history. GRANTing permissions on views or CDC logs require knowing their names, which are somewhat ugly (e.g., the name of GSI "abc" in table "xyz" is `alternator_xyz.xyz:abc`). But usefully, the error message when permissions are denied contains the full name of the table that was lacking permissions and which permissions were lacking, so users can easily add them. In addition to permissions checking, this series also correctly supports _auto-grant_ (except #19798): When a role has permissions to `CreateTable`, any table it creates will automatically be granted all permissions for this role, so this role will be able to use the new table and eventually delete it. `DeleteTable` does the opposite - it removes permissions from tables being deleted, so that if later a second user re-creates a table with the same name, the first user will not have permissions over the new table. The already-existing configuration parameter `alternator_enforce_authorization` (off by default), which previously only enabled authentication, now also enables authorization. Users that upgrade to the new version and already had `alternator_enforce_authorization=true` should verify that the users they use to authenticate either have the appropriate permissions or the "superuser" flag. Roles used to authenticate must also have the "login" flag. Please note that although the new RBAC support implements the access control feature we asked for in #5047, this implementation is _not compatible_ with DynamoDB. In DynamoDB, the access control is configured through IAM operations or through the new `PutResourcePolicy` - operation, not through CQL (obviously!). DynamoDB also offers finer access-control granularity than we support (Scylla's RBAC works on entire tables, DynamoDB allows setting permissions on key prefixes, on individual attributes, and more). Despite this non-compatibility, I believe this feature, as is, will already be useful to Alternator users. Fixes #5047 (after closing that issue, a new clean issue should be opened about the DynamoDB-compatible APIs that we didn't do - just so we remember this wasn't done yet). New feature, should not be backported. Closes scylladb/scylladb#20135 * github.com:scylladb/scylladb: tests: disable test_alternator_enforce_authorization_true test, alternator: test for alternator_enforce_authorization config test/pylib: allow setting driver_connect() options in servers_add() test: fix test_localnodes_joining_nodes alternator, RBAC: reproducer for missing CDC auto-grant alternator: document the new RBAC support alternator: add RBAC enforcement to GetRecords test/alternator: additional tests for RBAC test/alternator: reduce permissions-validity-in-ms test/alternator: add test for BatchGetItem from multiple tables alternator: test for operations that do not need any permissions alternator: add RBAC enforcement to UpdateTimeToLive alternator: add RBAC enforcement to TagResource and UntagResource alternator: add RBAC enforcement to BatchGetItem alternator: add RBAC enforcement to BatchWriteItem alternator: add RBAC enforcement to UpdateTable alternator: add RBAC enforcement to Query and Scan alternator: add RBAC enforcement to CreateTable alternator: add RBAC enforcement to DeleteTable alternator: add RBAC enforcement to UpdateItem alternator: add RBAC enforcement to DeleteItem alternator: add RBAC enforcement to PutItem alternator: add RBAC enforcement to GetItem alternator: stop using an "internal" client_state
ScyllaDB Documentation
This repository contains the source files for ScyllaDB Open Source documentation.
- The
devfolder contains developer-oriented documentation related to the ScyllaDB code base. It is not published and is only available via GitHub. - All other folders and files contain user-oriented documentation related to ScyllaDB Open Source and are sources for docs.scylladb.com.
To report a documentation bug or suggest an improvement, open an issue in GitHub issues for this project.
To contribute to the documentation, open a GitHub pull request.
Key Guidelines for Contributors
- Follow the ScyllaDB Style Guide.
- The user documentation is written in reStructuredText (RST) - a plaintext markup language similar to Markdown. If you're not familiar with RST, see ScyllaDB RST Examples.
- The developer documentation is written in Markdown. See Basic Markdown Syntax for reference.
Creating Knowledge Base Articles
The kb/ directory holds source files for knowledge base articles in the Knowledge Base section of the ScyllaDB documentation.
The kb/kb_common subdirectory contains a template for knowledge base articles to help you create new articles.
To create a new knowledge base article (KB):
- Copy the
kb-article-template.rstfile from/kb/kb_commonto/kband rename it with a unique name. - Open the new file and fill in the required information.
- Remove what is not needed.
- Run
make previewto build the docs and preview them locally. - Send a PR with "KB" in its title.
Building User Documentation
Prerequisites
- Python 3. Check your version with
$ python --version. - poetry 1.12 or later
- make
Mac OS X
You must have a working Homebrew in order to install the needed tools.
You also need the standard utility make.
Check if you have these two items with the following commands:
brew help
make -h
Linux Distributions
Building the user docs should work out of the box on most Linux distributions.
Windows
Use "Bash on Ubuntu on Windows" for the same tools and capabilities as on Linux distributions.
Building the Docs
- Run
make previewto build the documentation. - Preview the built documentation locally at http://127.0.0.1:5500/.
Cleanup
You can clean up all the build products and auto-installed Python stuff with:
make pristine
Information for Contributors
If you are interested in contributing to Scylla docs, please read the Scylla open source page at http://www.scylladb.com/opensource/ and complete a Scylla contributor agreement if needed. We can only accept documentation pull requests if we have a contributor agreement on file for you.
Third-party Documentation
-
Do any copying as a separate commit. Always commit an unmodified version first and then do any editing in a separate commit.
-
We already have a copy of the Apache license in our tree, so you do not need to commit a copy of the license.
-
Include the copyright header from the source file in the edited version. If you are copying an Apache Cassandra document with no copyright header, use:
This document includes material from Apache Cassandra.
Apache Cassandra is Copyright 2009-2014 The Apache Software Foundation.