This PR adds a new Module API int RM_AddACLCategory(RedisModuleCtx *ctx, const char *category_name) to add a new ACL command category.
Here, we initialize the ACLCommandCategories array by allocating space for 64 categories and duplicate the 21 default categories from the predefined array 'ACLDefaultCommandCategories' into the ACLCommandCategories array while ACL initialization. Valid ACL category names can only contain alphanumeric characters, underscores, and dashes.
The API when called, checks for the onload flag, category name validity, and for duplicate category name if present. If the conditions are satisfied, the API adds the new category to the trailing end of the ACLCommandCategories array and assigns the acl_categories flag bit according to the index at which the category is added.
If any error is encountered the errno is set accordingly by the API.
---------
Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>
This allows modules to register commands to existing ACL categories and blocks the creation of [sub]commands, datatypes and registering the configs outside of the OnLoad function.
For allowing modules to register commands to existing ACL categories,
This PR implements a new API int RM_SetCommandACLCategories() which takes a pointer to a RedisModuleCommand and a C string aclflags containing the set of space separated ACL categories.
Example, 'write slow' marks the command as part of the write and slow ACL categories.
The C string aclflags is tokenized by implementing a helper function categoryFlagsFromString(). Theses tokens are matched and the corresponding ACL categories flags are set by a helper function matchAclCategoriesFlags. The helper function categoryFlagsFromString() returns the corresponding categories_flags or returns -1 if some token not processed correctly.
If the module contains commands which are registered to existing ACL categories, the number of [sub]commands are tracked by num_commands_with_acl_categories in struct RedisModule. Further, the allowed command bit-map of the existing users are recomputed from the command_rules list, by implementing a function called ACLRecomputeCommandBitsFromCommandRulesAllUsers() for the existing users to have access to the module commands on runtime.
## Breaking change
This change requires that registering commands and subcommands only occur during a modules "OnLoad" function, in order to allow efficient recompilation of ACL bits. We also chose to block registering configs and types, since we believe it's only valid for those to be created during onLoad. We check for this onload flag in struct RedisModule to check if the call is made from the OnLoad function.
Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>
Motivation: for applications that use RM ACL verification functions, they would
want to return errors back to the user, in ways that are consistent with Redis.
While investigating how we should return ACL errors to the user, we realized that
Redis isn't consistent, and currently returns ACL error strings in 3 primary ways.
[For the actual implications of this change, see the "Impact" section at the bottom]
1. how it returns an error when calling a command normally
ACL_DENIED_CMD -> "this user has no permissions to run the '%s' command"
ACL_DENIED_KEY -> "this user has no permissions to access one of the keys used as arguments"
ACL_DENIED_CHANNEL -> "this user has no permissions to access one of the channels used as arguments"
2. how it returns an error when calling via 'acl dryrun' command
ACL_DENIED_CMD -> "This user has no permissions to run the '%s' command"
ACL_DENIED_KEY -> "This user has no permissions to access the '%s' key"
ACL_DENIED_CHANNEL -> "This user has no permissions to access the '%s' channel"
3. how it returns an error via RM_Call (and scripting is similar).
ACL_DENIED_CMD -> "can't run this command or subcommand";
ACL_DENIED_KEY -> "can't access at least one of the keys mentioned in the command arguments";
ACL_DENIED_CHANNEL -> "can't publish to the channel mentioned in the command";
In addition, if one wants to use RM_Call's "dry run" capability instead of the RM ACL
functions directly, one also sees a different problem than it returns ACL errors with a -ERR,
not a -PERM, so it can't be returned directly to the caller.
This PR modifies the code to generate a base message in a common manner with the ability
to set verbose flag for acl dry run errors, and keep it unset for normal/rm_call/script cases
```c
sds getAclErrorMessage(int acl_res, user *user, struct redisCommand *cmd, sds errored_val, int verbose) {
switch (acl_res) {
case ACL_DENIED_CMD:
return sdscatfmt(sdsempty(), "User %S has no permissions to run "
"the '%S' command", user->name, cmd->fullname);
case ACL_DENIED_KEY:
if (verbose) {
return sdscatfmt(sdsempty(), "User %S has no permissions to access "
"the '%S' key", user->name, errored_val);
} else {
return sdsnew("No permissions to access a key");
}
case ACL_DENIED_CHANNEL:
if (verbose) {
return sdscatfmt(sdsempty(), "User %S has no permissions to access "
"the '%S' channel", user->name, errored_val);
} else {
return sdsnew("No permissions to access a channel");
}
}
```
The caller can append/prepend the message (adding NOPERM for normal/RM_Call or indicating it's within a script).
Impact:
- Plain commands, as well as scripts and RM_Call now include the user name.
- ACL DRYRUN remains the only one that's verbose (mentions the offending channel or key name)
- Changes RM_Call ACL errors from being a `-ERR` to being `-NOPERM` (besides for textual changes)
**This somewhat a breaking change, but it only affects the RM_Call with both `C` and `E`, or `D`**
- Changes ACL errors in scripts textually from being
`The user executing the script <old non unified text>`
to
`ACL failure in script: <new unified text>`
Allow specifying an ACL log reason, which is shown in the log. Right now it always shows "unknown", which is a little bit cryptic. This is a breaking change, but this API was added as part of 7 so it seems ok to stabilize it still.
The PR extends RM_Call with 3 new capabilities using new flags that
are given to RM_Call as part of the `fmt` argument.
It aims to assist modules that are getting a list of commands to be
executed from the user (not hard coded as part of the module logic),
think of a module that implements a new scripting language...
* `S` - Run the command in a script mode, this means that it will raise an
error if a command which are not allowed inside a script (flaged with the
`deny-script` flag) is invoked (like SHUTDOWN). In addition, on script mode,
write commands are not allowed if there is not enough good replicas (as
configured with `min-replicas-to-write`) and/or a disk error happened.
* `W` - no writes mode, Redis will reject any command that is marked with `write`
flag. Again can be useful to modules that implement a new scripting language
and wants to prevent any write commands.
* `E` - Return errors as RedisModuleCallReply. Today the errors that happened
before the command was invoked (like unknown commands or acl error) return
a NULL reply and set errno. This might be missing important information about
the failure and it is also impossible to just pass the error to the user using
RM_ReplyWithCallReply. This new flag allows you to get a RedisModuleCallReply
object with the relevant error message and treat it as if it was an error that was
raised by the command invocation.
Tests were added to verify the new code paths.
In addition small refactoring was done to share some code between modules,
scripts, and `processCommand` function:
1. `getAclErrorMessage` was added to `acl.c` to unified to log message extraction
from the acl result
2. `checkGoodReplicasStatus` was added to `replication.c` to check the status of
good replicas. It is used on `scriptVerifyWriteCommandAllow`, `RM_Call`, and
`processCommand`.
3. `writeCommandsGetDiskErrorMessage` was added to `server.c` to get the error
message on persistence failure. Again it is used on `scriptVerifyWriteCommandAllow`,
`RM_Call`, and `processCommand`.
This implements the following main pieces of functionality:
* Renames key spec "CHANNEL" to be "NOT_KEY", and update the documentation to
indicate it's for cluster routing and not for any other key related purpose.
* Add the getchannels-api, so that modules can now define commands that are subject to
ACL channel permission checks.
* Add 4 new flags that describe how a module interacts with a command (SUBSCRIBE, PUBLISH,
UNSUBSCRIBE, and PATTERN). They are all technically composable, however not sure how a
command could both subscribe and unsubscribe from a command at once, but didn't see
a reason to add explicit validation there.
* Add two new module apis RM_ChannelAtPosWithFlags and RM_IsChannelsPositionRequest to
duplicate the functionality provided by the keys position APIs.
* The RM_ACLCheckChannelPermissions (only released in 7.0 RC1) was changed to take flags
rather than a boolean literal.
* The RM_ACLCheckKeyPermissions (only released in 7.0 RC1) was changed to take flags
corresponding to keyspecs instead of custom permission flags. These keyspec flags mimic
the flags for ACLCheckChannelPermissions.
SET is a R+W command, because it can also do `GET` on the data.
SET without GET is a write-only command.
SET with GET is a read+write command.
In #9974, we added ACL to let users define write-only access.
So when the user uses SET with GET option, and the user doesn't
have the READ permission on the key, we need to reject it,
but we rather not reject users with write-only permissions from using
the SET command when they don't use GET.
In this commit, we add a `getkeys_proc` function to control key
flags in SET command. We also add a new key spec flag (VARIABLE_FLAGS)
means that some keys might have different flags depending on arguments.
We also handle BITFIELD command, add a `bitfieldGetKeys` function.
BITFIELD GET is a READ ONLY command.
BITFIELD SET or BITFIELD INCR are READ WRITE commands.
Other changes:
1. SET GET was added in 6.2, add the missing since in set.json
2. Added tests to cover the changes in acl-v2.tcl
3. Fix some typos in server.h and cleanups in acl-v2.tcl
Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>
Co-authored-by: Oran Agra <oran@redislabs.com>
Summary of changes:
1. Rename `redisCommand->name` to `redisCommand->declared_name`, it is a
const char * for native commands and SDS for module commands.
2. Store the [sub]command fullname in `redisCommand->fullname` (sds).
3. List subcommands in `ACL CAT`
4. List subcommands in `COMMAND LIST`
5. `moduleUnregisterCommands` now will also free the module subcommands.
6. RM_GetCurrentCommandName returns full command name
Other changes:
1. Add `addReplyErrorArity` and `addReplyErrorExpireTime`
2. Remove `getFullCommandName` function that now is useless.
3. Some cleanups about `fullname` since now it is SDS.
4. Delete `populateSingleCommand` function from server.h that is useless.
5. Added tests to cover this change.
6. Add some module unload tests and fix the leaks
7. Make error messages uniform, make sure they always contain the full command
name and that it's quoted.
7. Fixes some typos
see the history in #9504, fixes#10124
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: guybe7 <guy.benoish@redislabs.com>
* Implemented selectors which provide multiple different sets of permissions to users
* Implemented key based permissions
* Added a new ACL dry-run command to test permissions before execution
* Updated module APIs to support checking key based permissions
Co-authored-by: Oran Agra <oran@redislabs.com>
This commit introduced a new flag to the RM_Call:
'C' - Check if the command can be executed according to the ACLs associated with it.
Also, three new API's added to check if a command, key, or channel can be executed or accessed
by a user, according to the ACLs associated with it.
- RM_ACLCheckCommandPerm
- RM_ACLCheckKeyPerm
- RM_ACLCheckChannelPerm
The user for these API's is a RedisModuleUser object, that for a Module user returned by the RM_CreateModuleUser API, or for a general ACL user can be retrieved by these two new API's:
- RM_GetCurrentUserName - Retrieve the user name of the client connection behind the current context.
- RM_GetModuleUserFromUserName - Get a RedisModuleUser from a user name
As a result of getting a RedisModuleUser from name, it can now also access the general ACL users (not just ones created by the module).
This mean the already existing API RM_SetModuleUserACL(), can be used to change the ACL rules for such users.
