This commit fixes a bug in the S3 gateway that causes
GET requests to fail when the object is encrypted by the
gateway itself.
The gateway was not able to GET the object since it always
specified a `If-Match` pre-condition checking that the object
ETag matches an expected ETag - even for encrypted ETags.
The problem is that an encrypted ETag will never match the ETag
computed by the backend causing the `If-Match` pre-condition
to fail.
This commit fixes this by not sending an `If-Match` header when
the ETag is encrypted. This is acceptable because:
1. A gateway-encrypted object consists of two objects at the backend
and there is no way to provide a concurrency-safe implementation
of two consecutive S3 GETs in the deployment model of the S3
gateway.
Ref: S3 gateways are self-contained and isolated - and there may
be multiple instances at the same time (no lock across
instances).
2. Even if the data object changes (concurrent PUT) while gateway
A has download the metadata object (but not issued the GET to
the data object => data race) then we don't return invalid data
to the client since the decryption (of the currently uploaded data)
will fail - given the metadata of the previous object.
The entire encryption layer is dependent on the fact that
KMS should be configured for S3 encryption to work properly
and we only support passing the headers as is to the backend
for encryption only if KMS is configured.
Make sure that this predictability is maintained, currently
the code was allowing encryption to go through and fail
at later to indicate that KMS was not configured. We should
simply reply "NotImplemented" if KMS is not configured, this
allows clients to simply proceed with their tests.
This is to ensure that Go contexts work properly, after some
interesting experiments I found that Go net/http doesn't
cancel the context when Body is non-zero and hasn't been
read till EOF.
The following gist explains this, this can lead to pile up
of go-routines on the server which will never be canceled
and will die at a really later point in time, which can
simply overwhelm the server.
https://gist.github.com/harshavardhana/c51dcfd055780eaeb71db54f9c589150
To avoid this refactor the locking such that we take locks after we
have started reading from the body and only take locks when needed.
Also, remove contextReader as it's not useful, doesn't work as expected
context is not canceled until the body reaches EOF so there is no point
in wrapping it with context and putting a `select {` on it which
can unnecessarily increase the CPU overhead.
We will still use the context to cancel the lockers etc.
Additional simplification in the locker code to avoid timers
as re-using them is a complicated ordeal avoid them in
the hot path, since locking is very common this may avoid
lots of allocations.
- Implement a new xl.json 2.0.0 format to support,
this moves the entire marshaling logic to POSIX
layer, top layer always consumes a common FileInfo
construct which simplifies the metadata reads.
- Implement list object versions
- Migrate to siphash from crchash for new deployments
for object placements.
Fixes#2111
Advantages avoids 100's of stats which are needed for each
upload operation in FS/NAS gateway mode when uploading a large
multipart object, dramatically increases performance for
multipart uploads by avoiding recursive calls.
For other gateway's simplifies the approach since
azure, gcs, hdfs gateway's don't capture any specific
metadata during upload which needs handler validation
for encryption/compression.
Erasure coding was already optimized, additionally
just avoids small allocations of large data structure.
Fixes#7206
enable linter using golangci-lint across
codebase to run a bunch of linters together,
we shall enable new linters as we fix more
things the codebase.
This PR fixes the first stage of this
cleanup.
This is a precursor change before versioning,
removes/deprecates the requirement of remembering
partName and partETag which are not useful after
a multipart transaction has finished.
This PR reduces the overall size of the backend
JSON for large file uploads.
This commit relaxes the restriction that the MinIO gateway
does not accept SSE-KMS headers. Now, the S3 gateway allows
SSE-KMS headers for PUT and MULTIPART PUT requests and forwards them
to the S3 gateway backend (AWS). This is considered SSE pass-through
mode.
Fixes#7753
CopyObject precondition checks into GetObjectReader
in order to perform SSE-C pre-condition checks using the
last 32 bytes of encrypted ETag rather than the decrypted
ETag
This also necessitates moving precondition checks for
gateways to gateway layer rather than object handler check
This PR adds pass-through, single encryption at gateway and double
encryption support (gateway encryption with pass through of SSE
headers to backend).
If KMS is set up (either with Vault as KMS or using
MINIO_SSE_MASTER_KEY),gateway will automatically perform
single encryption. If MINIO_GATEWAY_SSE is set up in addition to
Vault KMS, double encryption is performed.When neither KMS nor
MINIO_GATEWAY_SSE is set, do a pass through to backend.
When double encryption is specified, MINIO_GATEWAY_SSE can be set to
"C" for SSE-C encryption at gateway and backend, "S3" for SSE-S3
encryption at gateway/backend or both to support more than one option.
Fixes#6323, #6696
Andreas Auernhammer