This commit fixes a privilege escalation issue against
the S3 and web handlers. An authenticated IAM user
can:
- Read from or write to the internal '.minio.sys'
bucket by simply sending a properly signed
S3 GET or PUT request. Further, the user can
- Read from or write to the internal '.minio.sys'
bucket using the 'Upload'/'Download'/'DownloadZIP'
API by sending a "browser" request authenticated
with its JWT token.
guessIsRPCReq() considers all POST requests as RPC but doesn't
check if this is an object operation API or not, which is actually
confusing bucket forwarder handler when it receives a new multipart
upload API which is a POST http request.
Due to this bug, users having a federated setup are not able to
upload a multipart object using an endpoint which doesn't actually
contain the specified bucket that will store the object.
Hence this commit will fix the described issue.
This commit moves the check that SSE-C requests
must be made over TLS into a generic HTTP handler.
Since the HTTP server uses custom TCP connection handling
it is not possible to use `http.Request.TLS` to check
for TLS connections. So using `globalIsSSL` is the only
option to detect whether the request is made over TLS.
By extracting this check into a separate handler it's possible
to refactor other parts of the SSE handling code further.
Add support for sse-s3 encryption with vault as KMS.
Also refactoring code to make use of headers and functions defined in
crypto package and clean up duplicated code.
Added support for new RPC support using HTTP POST. RPC's
arguments and reply are Gob encoded and sent as HTTP
request/response body.
This patch also removes Go RPC based implementation.
This chnage replaces the current SSE-C key derivation scheme. The 'old'
scheme derives an unique object encryption key from the client provided key.
This key derivation was not invertible. That means that a client cannot change
its key without changing the object encryption key.
AWS S3 allows users to update there SSE-C keys by executing a SSE-C COPY with
source == destination. AWS probably updates just the metadata (which is a very
cheap operation). The old key derivation scheme would require a complete copy
of the object because the minio server would not be able to derive the same
object encryption key from a different client provided key (without breaking
the crypto. hash function).
This change makes the key derivation invertible.
This change adds server-side-encryption support for HEAD, GET and PUT
operations. This PR only addresses single-part PUTs and GETs without
HTTP ranges.
Further this change adds the concept of reserved object metadata which is required
to make encrypted objects tamper-proof and provide API compatibility to AWS S3.
This PR adds the following reserved metadata entries:
- X-Minio-Internal-Server-Side-Encryption-Iv ('guarantees' tamper-proof property)
- X-Minio-Internal-Server-Side-Encryption-Kdf (makes Key-MAC computation negotiable in future)
- X-Minio-Internal-Server-Side-Encryption-Key-Mac (provides AWS S3 API compatibility)
The prefix `X-Minio_Internal` specifies an internal metadata entry which must not
send to clients. All client requests containing a metadata key starting with `X-Minio-Internal`
must also rejected. This is implemented by a generic-handler.
This PR implements SSE-C separated from client-side-encryption (CSE). This cannot decrypt
server-side-encrypted objects on the client-side. However, clients can encrypted the same object
with CSE and SSE-C.
This PR does not address:
- SSE-C Copy and Copy part
- SSE-C GET with HTTP ranges
- SSE-C multipart PUT
- SSE-C Gateway
Each point must be addressed in a separate PR.
Added to vendor dir:
- x/crypto/chacha20poly1305
- x/crypto/poly1305
- github.com/minio/sio
All `net/rpc` requests go to `/minio`, so the existing
generic handler for reserved bucket check would essentially
erroneously send errors leading to distributed setups to
wait infinitely.
For `net/rpc` requests alone we should skip this check and
allow resource bucket names to be from `/minio` .
S3 only allows http headers with a size of 8 KB and user-defined metadata
with a size of 2 KB. This change adds a new API error and returns this
error to clients which sends to large http requests.
Fixes#4634
Make sure to skip reserved bucket names in `ListBuckets()`
current code didn't skip this properly and also generalize
this behavior for both XL and FS.
Jakob Ackermann