GRANT/REVOKE fails on the maintenance socket connections,
because maintenance_auth_service uses allow_all_authorizer.
allow_all_authorizer allows all operations, but not GRANT/REVOKE,
because they make no sense in its context.
This has been observed during PGO run failure in operations from
./pgo/conf/auth.cql file.
This patch introduces maintenance_socket_authorizer that supports
the capabilities of default_authorizer ('CassandraAuthorizer')
without needing authorization.
Refs SCYLLADB-1070
Replace the hardcoded meta::DEFAULT_SUPERUSER_NAME comparison with
default_superuser(_qp) which reads from the auth_superuser_name
config option. This makes the IF NOT EXISTS clause in DESCRIBE
output correct for clusters with a non-default superuser name.
Introduce maintenance_socket_authenticator and rework
maintenance_socket_role_manager to support role management operations.
Maintenance auth service uses allow_all_authenticator. To allow
role modification statements over the maintenance socket connections,
we need to treat the maintenance socket connections as superusers and
give them proper access rights.
Possible approaches are:
1. Modify allow_all_authenticator with conditional logic that
password_authenticator already does
2. Modify password_authenticator with conditional logic specific
for the maintenance socket connections
3. Extend password_authenticator, overriding the methods that differ
Option 3 is chosen: maintenance_socket_authenticator extends
password_authenticator with authentication disabled.
The maintenance_socket_role_manager is reworked to lazily create a
standard_role_manager once the node joins the cluster, delegating role
operations to it. In maintenance mode role operations remain disabled.
Refs SCYLLADB-409
This patch is part of preparations for dropping 'cassandra::cassandra'
default superuser. When that is implemented, maintenance_socket_role_manager
will have two modes of work:
1. in maintenance mode, where role operations are forbidden
2. in normal mode, where role operations are allowed
To execute the role operations, the node has to join a cluster.
In maintenance mode the node does not join a cluster.
This patch lets maintenance_socket_role_manager know if it works under
maintenance mode and returns appropriate error message when role
operations execution is requested.
Refs SCYLLADB-409
This patch removes class registrator usage in auth module.
It is not used after switching to factory functor initialization
of auth service.
Several role manager, authenticator, and authorizer name variables
are returned as well, and hardcoded inside qualified_java_name method,
since that is the only place they are ever used.
Refs SCYLLADB-409
Auth service can be initialized:
- [current] by passing instantiated authorizer, authenticator, role manager
- [current] by passing service_config, which then uses class registrator to instantiate authorizer, authenticator, role manager
- This approach is easy to use with sharded services
- [new] by passing factory functors which instantiate authorizer, authenticator, role manager
- This approach is also easy to use with sharded services
Refs SCYLLADB-409
In the following commit we'll need to add some
cache related logic (removing resource permissions).
This logic doesn't depend on authorizer so it should
be managed by the service itself.
Auth v2 migration uses non-paged queries via `execute_internal` API.
This commit changes it to use `query_internal` instead, which uses
paging under the hood.
Fixes: scylladb/scylladb#27577
Just move the touched code above so the next commit is more readable.
But this has a drawback: previously, if the returned rows were empty,
this code was not executed, but now is independently of the query
results. This shouldn't be a big deal, though, as auth shouldn't be
empty.
This patch series contains the following changes:
- Incorporation of `crypt_sha512.c` from musl to out codebase
- Conversion of `crypt_sha512.c` to C++ and coroutinization
- Coroutinization of `auth::passwords::check`
- Enabling use of `__crypt_sha512` orignated from `crypt_sha512.c` for
computing SHA 512 passwords of length <=255
- Addition of yielding in the aforementioned hashing implementation.
The alien thread was a solution for reactor stalls caused by indivisible
password‑hashing tasks (https://github.com/scylladb/scylladb/issues/24524).
However, because there is only one alien thread, overall hashing throughput was reduced
(see, e.g., https://github.com/scylladb/scylla-enterprise/issues/5711). To address this,
the alien‑thread solution is reverted, and a hashing implementation
with yielding is introduced in this patch series.
Before this patch series, ScyllaDB used SHA-512 hashing provided
by the `crypt_r` function, which in our case meant using the implementation
from the `libxcrypt` library. Adding yielding to this `libxcrypt`
implementation is problematic, both due to licensing (LGPL) and because the
implementation is split into many functions across multiple files. In
contrast, the SHA-512 implementation from `musl libc` has a more
permissive license and is concise, which makes it easier to incorporate
into the ScyllaDB codebase.
The performance of this solution was compared with the previous
implementation that used one alien thread and the implementation
after the alien thread was reverted. The results (median) of
`perf-cql-raw` with `--connection-per-request 1 --smp 10` parameters
are as follows:
- Alien thread: 41.5 new connections/s per shard
- Reverted alien thread: 244.1 new connections/s per shard
- This commit (yielding in hashing): 198.4 new connections/s per shard
The roughly 20% performance deterioration compared to
the old implementation without the alien thread comes from the fact
that the new hashing algorithm implemented in `utils/crypt_sha512.cc`
performs an expensive self-verification and stack cleanup.
On the other hand, with smp=10 the current implementation achieves
roughly 5x higher throughput than the alien thread. In addition,
due to yielding added in this commit, the algorithm is expected
to provide similar protection from stalls as the alien thread did.
In a test that in parallel started a cassandra-stress workload and
created thousands of new connections using python-driver, the values of
`scylla_reactor_stalls_count` metric were as follows:
- Alien thread: 109 stalls/shard total
- Reverted alien thread: 13186 stalls/shard total
- This commit (yielding in hashing): 149 stalls/shard total
Similarly, the `scylla_scheduler_time_spent_on_task_quota_violations_ms`
values were:
- Alien thread: 1087 ms/shard total
- Reverted alien thread: 72839 ms/shard total
- This commit (yielding in hashing): 1623 ms/shard total
To summarize, yielding during hashing computations achieves similar
throughput to the old solution without the alien thread but also
prevents stalls similarly to the alien thread.
Fixes: scylladb/scylladb#26859
Refs: scylladb/scylla-enterprise#5711
No automatic backport. After this PR is completed, the alien thread should be rather reverted from older branches (2025.2-2025.4 because on 2025.1 it's already removed). Backporting of the other commits needs further discussion.
Closesscylladb/scylladb#26860
* github.com:scylladb/scylladb:
test/boost: add too_long_password to auth_passwords_test
test/boost: add same_hashes_as_crypt_r to auth_passwords_test
auth: utils: add yielding to crypt_sha512
auth: change return type of passwords::check to future
auth: remove code duplication in verify_scheme
test/boost: coroutinize auth_passwords_test
utils: coroutinize crypt_sha512
utils: make crypt_sha512.cc to compile
utils: license: import crypt_sha512.c from musl to the project
Revert "auth: move passwords::check call to alien thread"
The alien thread was a solution for reactor stalls caused by indivisible
password‑hashing tasks (scylladb/scylladb#24524). However, because
there is only one alien thread, overall hashing throughput was reduced
(see, e.g., scylladb/scylla-enterprise#5711). To address this,
the alien‑thread solution is reverted, and a hashing implementation
with yielding will be introduced later in this patch series.
This reverts commit 9574513ec1.
We want to add strongly consistent tables as an option. We will have
two kind of strongly consistent tables: globally consistent and locally
consistent. The former means that requests from all DCs will be globally
linearisable while the later - only requests to the same DCs will be
linearisable. To allow configuring all the possibilities the patch
adds new parameter to a keyspace definition "consistency" that can be
configured to be `eventual`, `global` or `local`. Non eventual setting
is supported for tablets enabled keyspaces only. Since we want to start
with implementing local consistency configuring global consistency will
result in an error for now.
As requested in #22104, moved the files and fixed other includes and build system.
Moved files:
- combine.hh
- collection_mutation.hh
- collection_mutation.cc
- converting_mutation_partition_applier.hh
- converting_mutation_partition_applier.cc
- counters.hh
- counters.cc
- timestamp.hh
Fixes: #22104
This is a cleanup, no need to backport
Closesscylladb/scylladb#25085
Analysis of customer stalls revealed that the function `detail::hash_with_salt` (invoked by `passwords::check`) often blocks the reactor. Internally, this function uses the external `crypt_r` function to compute password hashes, which is CPU-intensive.
This PR addresses the issue in two ways:
1) `sha-512` is now the only password hashing scheme for new passwords (it was already the common-case).
2) `passwords::check` is moved to a dedicated alien thread.
Regarding point 1: before this change, the following hashing schemes were supported by `identify_best_supported_scheme()`: bcrypt_y, bcrypt_a, SHA-512, SHA-256, and MD5. The reason for this was that the `crypt_r` function used for password hashing comes from an external library (currently `libxcrypt`), and the supported hashing algorithms vary depending on the library in use. However:
- The bcrypt schemes never worked properly because their prefixes lack the required round count (e.g. `$2y$` instead of `$2y$05$`). Moreover, bcrypt is slower than SHA-512, so it not good idea to fix or use it.
- SHA-256 and SHA-512 both belong to the SHA-2 family. Libraries that support one almost always support the other, so it’s very unlikely to find SHA-256 without SHA-512.
- MD5 is no longer considered secure for password hashing.
Regarding point 2: the `passwords::check` call now runs on a shared alien thread created at database startup. An `std::mutex` synchronizes that thread with the shards. In theory this could introduce a frequent lock contention, but in practice each shard handles only a few hundred new connections per second—even during storms. There is already `_conns_cpu_concurrency_semaphore` in `generic_server` limits the number of concurrent connection handlers.
Fixes https://github.com/scylladb/scylladb/issues/24524
Backport not needed, as it is a new feature.
Closesscylladb/scylladb#24924
* github.com:scylladb/scylladb:
main: utils: add thread names to alien workers
auth: move passwords::check call to alien thread
test: wait for 3 clients with given username in test_service_level_api
auth: refactor password checking in password_authenticator
auth: make SHA-512 the only password hashing scheme for new passwords
auth: whitespace change in identify_best_supported_scheme()
auth: require scheme as parameter for `generate_salt`
auth: check password hashing scheme support on authenticator start
Analysis of customer stalls showed that the `detail::hash_with_salt`
function, called from `passwords::check`, often blocks the reactor.
This function internally uses the `crypt_r` function from an external
library to compute password hashes, which is a CPU-intensive operation.
To prevent such reactor stalls, this commit moves the
`passwords::check` call to a dedicated alien thread. This thread is
created at system startup and is shared by all shards.
Within the alien thread, an `std::mutex` synchronizes access between
the thread and the shards. While this could theoretically cause
frequent lock contentions, in practice, even during connection storms,
the number of new connections per second per shard is limited
(typically hundreds per second). Additionally, the
`_conns_cpu_concurrency_semaphore` in `generic_server` ensures that not
too many connections are processed at once.
Fixesscylladb/scylladb#24524
It's not a good usage as there is only one non-empty implementation.
Also we need to change it further in the following commit which
makes it incompatible with listener code.
When describing a table, we need to do it carefully: if some
columns were dropped, we must specify that explicitly by
```
ALTER TABLE {table} DROP {column} USING TIMESTAMP ...
```
in the result of the DESCRIBE statement. Failing to do so
could lead to data resurrection.
However, if a table has been altered many, many times,
we might end up with a huge create statement. Constructing
it could, in turn, trigger an oversized allocation.
Some tests ran into that very problem in fact.
In this commit, we want to mitigate the problem: instead of
allocating a contiguous chunk of memory for the create
statement, we use `fragmented_ostringstream` and `managed_string`
to possibly keep data scattered in memory. It makes handling
`cql3::description` less convenient in the code, but since
the struct is pretty much immediately serialized after
creating it, it's a very good trade-off.
We provide a reproducer. It consistently passes with this commit,
while having about 50% chance of failure before it (based on my
own experiments). Playing with the parameters of the test
doesn't seem to improve that chance, so let's keep it as-is.
Fixesscylladb/scylladb#24018
There is a hidden dependency: the creation of the default superuser role
is split between the password authenticator and the role manager.
To work correctly, they must start in the right order: role manager first,
then password authenticator.
This reverts commit 0b516da95b, reversing
changes made to 30199552ac. It breaks
cluster.random_failures.test_random_failures.test_random_failures
in debug mode (at least).
Fixes#24513
It's not a good usage as there is only one non-empty implementation.
Also we need to change it further in the following commit which
makes it incompatible with listener code.
Blobs can be large, and unfragmented blobs can easily exceed 128k
(as seen in #23903). Rename get_blob() to get_blob_unfragmented()
to warn users.
Note that most uses are fine as the blobs are really short strings.
Closesscylladb/scylladb#24102
It's possible to modify 'memtable_flush_period_in_ms' option only and as
single option, not with any other options together
Refs #20999Fixes#21223Closesscylladb/scylladb#22536
Before this change, it was ensured that a default superuser is created
before serving CQL. However, the mechanism didn't wait for default
password initialization, so effectively, for a short period, customer
couldn't authenticate as the superuser properily. The purpose of this
change is to improve the superuser initialization mechanism to wait for
superuser default password, just as for the superuser creation.
This change:
- Introduce authenticator::ensure_superuser_is_created() to allow
waiting for complete initialization of super user authentication
- Implement ensure_superuser_is_created in password_authenticator, so
waiting for superuser password initialization is possible
- Implement ensure_superuser_is_create in transitional_authenticator,
so the implementation from password_authenticator is used
- Implement no-op ensure_superuser_is_create for other authenticators
- Modify service::ensure_superuser_is_created to wait for superuser
initialization in authenticator, just as it was implemented earlier
for role_manager
Fixesscylladb/scylladb#20566
Replace usages of `boost::algorithm::join()` with `fmt::join()` to improve
performance and reduce dependency on Boost. `fmt::join()` allows direct
formatting of ranges and tuples with custom separators without creating
intermediate strings.
When formatting comma-separated values into another string, fmt::join()
avoids the overhead of temporary string creation that
`boost::algorithm::join()` requires. This change also helps streamline
our dependencies by leveraging the existing fmt library instead of
Boost.Algorithm.
To avoid the ambiguity, some caller sites were updated to call
`seastar::format()` explicitly.
See also
- boost::algorithm::join():
https://www.boost.org/doc/libs/1_87_0/doc/html/string_algo/reference.html#doxygen.join_8hpp
- fmt::join():
https://fmt.dev/11.0/api/#ranges-api
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#22082
these unused includes are identified by clang-include-cleaner. after
auditing the source files, all of the reports have been confirmed.
please note, because `mutation/mutation.hh` does not include
`seastar/coroutine/maybe_yield.hh` anymore, and quite a few source
files were relying on this header to bring in the declaration of
`maybe_yield()`, we have to include this header in the places where
this symbol is used. the same applies to `seastar/core/when_all.hh`.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Cassandra 4.1 announced a new option to create a role with:
`HASHED PASSWORD`. Example:
```
CREATE ROLE bob WITH HASHED PASSWORD = 'hashed_password';
```
We've already introduced another option following the same
semantics: `SALTED HASH`; example:
```
CREATE ROLE bob WITH SALTED HASH = 'salted_hash';
```
The change hasn't made it to any release yet, so in this commit
we rename it to `HASHED PASSWORD` to be compatible with Cassandra.
Additionally, we adjust existing tests to work against Cassandra too.
Fixesscylladb/scylladb#21350Closesscylladb/scylladb#21352
the log.hh under the root of the tree was created keep the backward
compatibility when seastar was extracted into a separate library.
so log.hh should belong to `utils` directory, as it is based solely
on seastar, and can be used all subsystems.
in this change, we move log.hh into utils/log.hh to that it is more
modularized. and this also improves the readability, when one see
`#include "utils/log.hh"`, it is obvious that this source file
needs the logging system, instead of its own log facility -- please
note, we do have two other `log.hh` in the tree.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
This change reorganizes the way standard_role_manager startup is
handled: now the future returned by its start() function can be used to
determine when startup has finished. We use this future to ensure the
startup is finished prior to starting the CQL server.
Some clusters are created without auth, and auth is added later. The
first node to recognize that auth is needed must create the superuser.
Currently this is always on restart, but if we were to ever make it
LiveUpdate then it would not be on restart.
This suggests that we don't really need to wait during restart.
This is a preparatory commit, laying ground for implementation of a
start() function that waits for the superuser to be created. The default
implementation returns a ready future, which makes no change in the code
behavior.
We introduce a function `describe_auth()` in `auth::service`
responsible for producing a sequence of descriptions whose
corresponding CQL statement can be used to restore the state
of auth.
We introduce a way to create a role with explictly
provided salted hash.
The algorithm for creating a role with a password works
like this:
1. The user issues a statement `CREATE ROLE <role> WITH
PASSWORD = '<password>' <...>`.
2. Scylla produces a hash based on the value of
`<password>`.
3. Scylla puts the produced hash in `system.roles`,
in the column `salted_hash`.
The newly introduced way to create a role is based
on a new form of the create statement:
`CREATE ROLE <role> WITH SALTED HASH = '<salted_hash>`
The difference in the algorithm used for processing
this statement is that we insert `<salted_hash>`
into `system.roles` directly, without hashing it.
The rationale for introducing this new statement is that
we want to be able to restore roles. The original password
isn't stored anywhere in the database (as intended),
so we need to rely on the column `salted_hash`.
before this change, we rely on `using namespace seastar` to use
`seastar::format()` without qualifying the `format()` with its
namespace. this works fine until we changed the parameter type
of format string `seastar::format()` from `const char*` to
`fmt::format_string<...>`. this change practically invited
`seastar::format()` to the club of `std::format()` and `fmt::format()`,
where all members accept a templated parameter as its `fmt`
parameter. and `seastar::format()` is not the best candidate anymore.
despite that argument-dependent lookup (ADT for short) favors the
function which is in the same namespace as its parameter, but
`using namespace` makes `seastar::format()` more competitive,
so both `std::format()` and `seastar::format()` are considered
as the condidates.
that is what is happening scylladb in quite a few caller sites of
`format()`, hence ADT is not able to tell which function the winner
in the name lookup:
```
/__w/scylladb/scylladb/mutation/mutation_fragment_stream_validator.cc:265:12: error: call to 'format' is ambiguous
265 | return format("{} ({}.{} {})", _name_view, s.ks_name(), s.cf_name(), s.id());
| ^~~~~~
/usr/bin/../lib/gcc/x86_64-redhat-linux/14/../../../../include/c++/14/format:4290:5: note: candidate function [with _Args = <const std::basic_string_view<char> &, const seastar::basic_sstring<char, unsigned int, 15> &, const seastar::basic_sstring<char, unsigned int, 15> &, const utils::tagged_uuid<table_id_tag> &>]
4290 | format(format_string<_Args...> __fmt, _Args&&... __args)
| ^
/__w/scylladb/scylladb/seastar/include/seastar/core/print.hh:143:1: note: candidate function [with A = <const std::basic_string_view<char> &, const seastar::basic_sstring<char, unsigned int, 15> &, const seastar::basic_sstring<char, unsigned int, 15> &, const utils::tagged_uuid<table_id_tag> &>]
143 | format(fmt::format_string<A...> fmt, A&&... a) {
| ^
```
in this change, we
change all `format()` to either `fmt::format()` or `seastar::format()`
with following rules:
- if the caller expects an `sstring` or `std::string_view`, change to
`seastar::format()`
- if the caller expects an `std::string`, change to `fmt::format()`.
because, `sstring::operator std::basic_string` would incur a deep
copy.
we will need another change to enable scylladb to compile with the
latest seastar. namely, to pass the format string as a templated
parameter down to helper functions which format their parameters.
to miminize the scope of this change, let's include that change when
bumping up the seastar submodule. as that change will depend on
the seastar change.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
The hint contains information related to what exactly changed, allowing
listeners to do partial updates, instead of reloading all metadata on
each notification.
assert() is traditionally disabled in release builds, but not in
scylladb. This hasn't caused problems so far, but the latest abseil
release includes a commit [1] that causes a 1000 insn/op regression when
NDEBUG is not defined.
Clearly, we must move towards a build system where NDEBUG is defined in
release builds. But we can't just define it blindly without vetting
all the assert() calls, as some were written with the expectation that
they are enabled in release mode.
To solve the conundrum, change all assert() calls to a new SCYLLA_ASSERT()
macro in utils/assert.hh. This macro is always defined and is not conditional
on NDEBUG, so we can later (after vetting Seastar) enable NDEBUG in release
mode.
[1] 66ef711d68Closesscylladb/scylladb#20006
Most callers of the raft group0 client interface are passing a real
source instance, so we can use the abort source reference in the client
interface. This change makes the code simpler and more consistent.
This is done to ease code reuse in the following commit.
It'd also help should we ever want properly mount functions
class to schema object instead of static storage.
this change was created in the same spirit of ebff5f5d.
despite that we include Seastar as a submodule, Seastar is not a
part of scylla project. so we'd better include its headers using
brackets.
ebff5f5d addressed this cosmetic issue a while back. but probably
clangd's header-insertion helped some of contributor to insert
the missing headers with `"`. so this style of `include` returned
to the tree with these new changes.
unfortunately, clangd does not allow us to configure the style
of `include` at the time of writing.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#19406
With big number of shards in the cluster (e.g. 500+) due to cache
periodic refresh we experience high load on role_permissions table
(e.g. 1k op/s). The load on roles table is amplified because to populate
single entry in the cache we do several selects on roles table. Some
of this can't be avoided because roles are arranged in a tree-like
structure where permissions can be inherited.
This patch tries to reuse queries which are simply duplicated. It should
reduce the load on roles table by up to 50%.
Fixesscylladb/scylladb#19299
