use garage_util::crdt::*;
use garage_util::data::*;
use garage_util::error::{Error as GarageError, OkOrMessage};
use garage_util::time::*;
use garage_table::util::*;
use crate::bucket_alias_table::*;
use crate::garage::Garage;
use crate::helper::bucket::BucketHelper;
use crate::helper::error::*;
use crate::helper::key::KeyHelper;
use crate::key_table::*;
use crate::permission::BucketKeyPerm;
/// A LockedHelper is the mandatory struct to hold when doing operations
/// that modify access keys or bucket aliases. This structure takes
/// a lock to a unit value that is in the globally-shared Garage struct.
///
/// This avoid several concurrent requests to modify the list of buckets
/// and aliases at the same time, ending up in inconsistent states.
/// This DOES NOT FIX THE FUNDAMENTAL ISSUE as CreateBucket requests handled
/// by different API nodes can still break the cluster, but it is a first
/// fix that allows consistency to be maintained if all such requests are
/// directed to a single node, which is doable for many deployments.
///
/// See issues: #649, #723
pub struct LockedHelper<'a>(
pub(crate) &'a Garage,
pub(crate) tokio::sync::MutexGuard<'a, ()>,
);
#[allow(clippy::ptr_arg)]
impl<'a> LockedHelper<'a> {
pub fn bucket(&self) -> BucketHelper<'a> {
BucketHelper(self.0)
}
pub fn key(&self) -> KeyHelper<'a> {
KeyHelper(self.0)
}
/// Sets a new alias for a bucket in global namespace.
/// This function fails if:
/// - alias name is not valid according to S3 spec
/// - bucket does not exist or is deleted
/// - alias already exists and points to another bucket
pub async fn set_global_bucket_alias(
&self,
bucket_id: Uuid,
alias_name: &String,
) -> Result<(), Error> {
if !is_valid_bucket_name(alias_name) {
return Err(Error::InvalidBucketName(alias_name.to_string()));
}
let mut bucket = self.bucket().get_existing_bucket(bucket_id).await?;
let alias = self.0.bucket_alias_table.get(&EmptyKey, alias_name).await?;
if let Some(existing_alias) = alias.as_ref() {
if let Some(p_bucket) = existing_alias.state.get() {
if *p_bucket != bucket_id {
return Err(Error::BadRequest(format!(
"Alias {} already exists and points to different bucket: {:?}",
alias_name, p_bucket
)));
}
}
}
// Checks ok, add alias
let bucket_p = bucket.state.as_option_mut().unwrap();
let alias_ts = increment_logical_clock_2(
bucket_p.aliases.get_timestamp(alias_name),
alias.as_ref().map(|a| a.state.timestamp()).unwrap_or(0),
);
// ---- timestamp-ensured causality barrier ----
// writes are now done and all writes use timestamp alias_ts
let alias = match alias {
None => BucketAlias::new(alias_name.clone(), alias_ts, Some(bucket_id))
.ok_or_else(|| Error::InvalidBucketName(alias_name.clone()))?,
Some(mut a) => {
a.state = Lww::raw(alias_ts, Some(bucket_id));
a
}
};
self.0.bucket_alias_table.insert(&alias).await?;
bucket_p.aliases = LwwMap::raw_item(alias_name.clone(), alias_ts, true);
self.0.bucket_table.insert(&bucket).await?;
Ok(())
}
/// Unsets an alias for a bucket in global namespace.
/// This function fails if:
/// - bucket does not exist or is deleted
/// - alias does not exist or maps to another bucket (-> internal error)
/// - bucket has no other aliases (global or local)
pub async fn unset_global_bucket_alias(
&self,
bucket_id: Uuid,
alias_name: &String,
) -> Result<(), Error> {
let mut bucket = self.bucket().get_existing_bucket(bucket_id).await?;
let bucket_state = bucket.state.as_option_mut().unwrap();
let mut alias = self
.0
.bucket_alias_table
.get(&EmptyKey, alias_name)
.await?
.filter(|a| a.state.get().map(|x| x == bucket_id).unwrap_or(false))
.ok_or_message(format!(
"Internal error: alias not found or does not point to bucket {:?}",
bucket_id
))?;
let has_other_global_aliases = bucket_state
.aliases
.items()
.iter()
.any(|(name, _, active)| name != alias_name && *active);
let has_other_local_aliases = bucket_state
.local_aliases
.items()
.iter()
.any(|(_, _, active)| *active);
if !has_other_global_aliases && !has_other_local_aliases {
return Err(Error::BadRequest(format!("Bucket {} doesn't have other aliases, please delete it instead of just unaliasing.", alias_name)));
}
// Checks ok, remove alias
let alias_ts = increment_logical_clock_2(
alias.state.timestamp(),
bucket_state.aliases.get_timestamp(alias_name),
);
// ---- timestamp-ensured causality barrier ----
// writes are now done and all writes use timestamp alias_ts
alias.state = Lww::raw(alias_ts, None);
self.0.bucket_alias_table.insert(&alias).await?;
bucket_state.aliases = LwwMap::raw_item(alias_name.clone(), alias_ts, false);
self.0.bucket_table.insert(&bucket).await?;
Ok(())
}
/// Ensures a bucket does not have a certain global alias.
/// Contrarily to unset_global_bucket_alias, this does not
/// fail on any condition other than:
/// - bucket cannot be found (its fine if it is in deleted state)
/// - alias cannot be found (its fine if it points to nothing or
/// to another bucket)
pub async fn purge_global_bucket_alias(
&self,
bucket_id: Uuid,
alias_name: &String,
) -> Result<(), Error> {
let mut bucket = self.bucket().get_internal_bucket(bucket_id).await?;
let mut alias = self
.0
.bucket_alias_table
.get(&EmptyKey, alias_name)
.await?
.ok_or_else(|| Error::NoSuchBucket(alias_name.to_string()))?;
// Checks ok, remove alias
let alias_ts = match bucket.state.as_option() {
Some(bucket_state) => increment_logical_clock_2(
alias.state.timestamp(),
bucket_state.aliases.get_timestamp(alias_name),
),
None => increment_logical_clock(alias.state.timestamp()),
};
// ---- timestamp-ensured causality barrier ----
// writes are now done and all writes use timestamp alias_ts
if alias.state.get() == &Some(bucket_id) {
alias.state = Lww::raw(alias_ts, None);
self.0.bucket_alias_table.insert(&alias).await?;
}
if let Some(bucket_state) = bucket.state.as_option_mut() {
bucket_state.aliases = LwwMap::raw_item(alias_name.clone(), alias_ts, false);
self.0.bucket_table.insert(&bucket).await?;
}
Ok(())
}
/// Sets a new alias for a bucket in the local namespace of a key.
/// This function fails if:
/// - alias name is not valid according to S3 spec
/// - bucket does not exist or is deleted
/// - key does not exist or is deleted
/// - alias already exists and points to another bucket
pub async fn set_local_bucket_alias(
&self,
bucket_id: Uuid,
key_id: &String,
alias_name: &String,
) -> Result<(), Error> {
let key_helper = KeyHelper(self.0);
if !is_valid_bucket_name(alias_name) {
return Err(Error::InvalidBucketName(alias_name.to_string()));
}
let mut bucket = self.bucket().get_existing_bucket(bucket_id).await?;
let mut key = key_helper.get_existing_key(key_id).await?;
let key_param = key.state.as_option_mut().unwrap();
if let Some(Some(existing_alias)) = key_param.local_aliases.get(alias_name) {
if *existing_alias != bucket_id {
return Err(Error::BadRequest(format!("Alias {} already exists in namespace of key {} and points to different bucket: {:?}", alias_name, key.key_id, existing_alias)));
}
}
// Checks ok, add alias
let bucket_p = bucket.state.as_option_mut().unwrap();
let bucket_p_local_alias_key = (key.key_id.clone(), alias_name.clone());
// Calculate the timestamp to assign to this aliasing in the two local_aliases maps
// (the one from key to bucket, and the reverse one stored in the bucket iself)
// so that merges on both maps in case of a concurrent operation resolve
// to the same alias being set
let alias_ts = increment_logical_clock_2(
key_param.local_aliases.get_timestamp(alias_name),
bucket_p
.local_aliases
.get_timestamp(&bucket_p_local_alias_key),
);
// ---- timestamp-ensured causality barrier ----
// writes are now done and all writes use timestamp alias_ts
key_param.local_aliases = LwwMap::raw_item(alias_name.clone(), alias_ts, Some(bucket_id));
self.0.key_table.insert(&key).await?;
bucket_p.local_aliases = LwwMap::raw_item(bucket_p_local_alias_key, alias_ts, true);
self.0.bucket_table.insert(&bucket).await?;
Ok(())
}
/// Unsets an alias for a bucket in the local namespace of a key.
/// This function fails if:
/// - bucket does not exist or is deleted
/// - key does not exist or is deleted
/// - alias does not exist or maps to another bucket (-> internal error)
/// - bucket has no other aliases (global or local)
pub async fn unset_local_bucket_alias(
&self,
bucket_id: Uuid,
key_id: &String,
alias_name: &String,
) -> Result<(), Error> {
let key_helper = KeyHelper(self.0);
let mut bucket = self.bucket().get_existing_bucket(bucket_id).await?;
let mut key = key_helper.get_existing_key(key_id).await?;
let bucket_p = bucket.state.as_option_mut().unwrap();
if key
.state
.as_option()
.unwrap()
.local_aliases
.get(alias_name)
.cloned()
.flatten() != Some(bucket_id)
{
return Err(GarageError::Message(format!(
"Bucket {:?} does not have alias {} in namespace of key {}",
bucket_id, alias_name, key_id
))
.into());
}
let has_other_global_aliases = bucket_p
.aliases
.items()
.iter()
.any(|(_, _, active)| *active);
let has_other_local_aliases = bucket_p
.local_aliases
.items()
.iter()
.any(|((k, n), _, active)| *k == key.key_id && n == alias_name && *active);
if !has_other_global_aliases && !has_other_local_aliases {
return Err(Error::BadRequest(format!("Bucket {} doesn't have other aliases, please delete it instead of just unaliasing.", alias_name)));
}
// Checks ok, remove alias
let key_param = key.state.as_option_mut().unwrap();
let bucket_p_local_alias_key = (key.key_id.clone(), alias_name.clone());
let alias_ts = increment_logical_clock_2(
key_param.local_aliases.get_timestamp(alias_name),
bucket_p
.local_aliases
.get_timestamp(&bucket_p_local_alias_key),
);
// ---- timestamp-ensured causality barrier ----
// writes are now done and all writes use timestamp alias_ts
key_param.local_aliases = LwwMap::raw_item(alias_name.clone(), alias_ts, None);
self.0.key_table.insert(&key).await?;
bucket_p.local_aliases = LwwMap::raw_item(bucket_p_local_alias_key, alias_ts, false);
self.0.bucket_table.insert(&bucket).await?;
Ok(())
}
/// Sets permissions for a key on a bucket.
/// This function fails if:
/// - bucket or key cannot be found at all (its ok if they are in deleted state)
/// - bucket or key is in deleted state and we are trying to set permissions other than "deny
/// all"
pub async fn set_bucket_key_permissions(
&self,
bucket_id: Uuid,
key_id: &String,
mut perm: BucketKeyPerm,
) -> Result<(), Error> {
let key_helper = KeyHelper(self.0);
let mut bucket = self.bucket().get_internal_bucket(bucket_id).await?;
let mut key = key_helper.get_internal_key(key_id).await?;
if let Some(bstate) = bucket.state.as_option() {
if let Some(kp) = bstate.authorized_keys.get(key_id) {
perm.timestamp = increment_logical_clock_2(perm.timestamp, kp.timestamp);
}
} else if perm.is_any() {
return Err(Error::BadRequest(
"Trying to give permissions on a deleted bucket".into(),
));
}
if let Some(kstate) = key.state.as_option() {
if let Some(bp) = kstate.authorized_buckets.get(&bucket_id) {
perm.timestamp = increment_logical_clock_2(perm.timestamp, bp.timestamp);
}
} else if perm.is_any() {
return Err(Error::BadRequest(
"Trying to give permissions to a deleted key".into(),
));
}
// ---- timestamp-ensured causality barrier ----
if let Some(bstate) = bucket.state.as_option_mut() {
bstate.authorized_keys = Map::put_mutator(key_id.clone(), perm);
self.0.bucket_table.insert(&bucket).await?;
}
if let Some(kstate) = key.state.as_option_mut() {
kstate.authorized_buckets = Map::put_mutator(bucket_id, perm);
self.0.key_table.insert(&key).await?;
}
Ok(())
}
// ----
/// Deletes an API access key
pub async fn delete_key(&self, key: &mut Key) -> Result<(), Error> {
let state = key.state.as_option_mut().unwrap();
// --- done checking, now commit ---
// (the step at unset_local_bucket_alias will fail if a bucket
// does not have another alias, the deletion will be
// interrupted in the middle if that happens)
// 1. Delete local aliases
for (alias, _, to) in state.local_aliases.items().iter() {
if let Some(bucket_id) = to {
self.unset_local_bucket_alias(*bucket_id, &key.key_id, alias)
.await?;
}
}
// 2. Remove permissions on all authorized buckets
for (ab_id, _auth) in state.authorized_buckets.items().iter() {
self.set_bucket_key_permissions(*ab_id, &key.key_id, BucketKeyPerm::NO_PERMISSIONS)
.await?;
}
// 3. Actually delete key
key.state = Deletable::delete();
self.0.key_table.insert(key).await?;
Ok(())
}
}
