This change replaces the non-constant time comparison of
request signatures with a constant time implementation. This
prevents a timing attack which can be used to learn a valid
signature for a request without knowing the secret key.
Fixes#5334
This change introduces following simplified steps to follow
during config migration.
```
// Steps to move from version N to version N+1
// 1. Add new struct serverConfigVN+1 in config-versions.go
// 2. Set configCurrentVersion to "N+1"
// 3. Set serverConfigCurrent to serverConfigVN+1
// 4. Add new migration function (ex. func migrateVNToVN+1()) in config-migrate.go
// 5. Call migrateVNToVN+1() from migrateConfig() in config-migrate.go
// 6. Make changes in config-current_test.go for any test change
```
It is possible that x-amz-content-sha256 is set through
the query params in case of presigned PUT calls, make sure
that we validate the incoming x-amz-content-sha256 properly.
Current code simply just allows this without honoring the
set x-amz-content-sha256, fix it.
We don't need to typecast identifiers from
their base to type to same type again. This
is not a bug and compiler is fine to skip
it but it is better to avoid if not needed.
This change is cleanup of the postPolicyHandler code
primarily to address the flow and also converting
certain critical parts into self contained functions.
This is a consolidation effort, avoiding usage
of naked strings in codebase. Whenever possible
use constants which can be repurposed elsewhere.
This also fixes `goconst ./...` reported issues.
* Implements a Peer RPC router that sends info to all Minio servers in the cluster.
* Bucket notifications are propagated to all nodes via this RPC router.
* Bucket listener configuration is persisted to separate object layer
file (`listener.json`) and peer RPCs are used to communicate changes
throughout the cluster.
* When events are generated, RPC calls to send them to other servers
where bucket listeners may be connected is implemented.
* Some bucket notification tests are now disabled as they cannot work in
the new design.
* Minor fix in `funcFromPC` to use `path.Join`
