This commit refactors the SSE implementation and add
S3-compatible SSE-KMS context handling.
SSE-KMS differs from SSE-S3 in two main aspects:
1. The client can request a particular key and
specify a KMS context as part of the request.
2. The ETag of an SSE-KMS encrypted object is not
the MD5 sum of the object content.
This commit only focuses on the 1st aspect.
A client can send an optional SSE context when using
SSE-KMS. This context is remembered by the S3 server
such that the client does not have to specify the
context again (during multipart PUT / GET / HEAD ...).
The crypto. context also includes the bucket/object
name to prevent renaming objects at the backend.
Now, AWS S3 behaves as following:
- If the user does not provide a SSE-KMS context
it does not store one - resp. does not include
the SSE-KMS context header in the response (e.g. HEAD).
- If the user specifies a SSE-KMS context without
the bucket/object name then AWS stores the exact
context the client provided but adds the bucket/object
name internally. The response contains the KMS context
without the bucket/object name.
- If the user specifies a SSE-KMS context with
the bucket/object name then AWS again stores the exact
context provided by the client. The response contains
the KMS context with the bucket/object name.
This commit implements this behavior w.r.t. SSE-KMS.
However, as of now, no such object can be created since
the server rejects SSE-KMS encryption requests.
This commit is one stepping stone for SSE-KMS support.
Co-authored-by: Harshavardhana <harsha@minio.io>
This commit refactors the code in `cmd/crypto`
and separates SSE-S3, SSE-C and SSE-KMS.
This commit should not cause any behavior change
except for:
- `IsRequested(http.Header)`
which now returns the requested type {SSE-C, SSE-S3,
SSE-KMS} and does not consider SSE-C copy headers.
However, SSE-C copy headers alone are anyway not valid.
`decryptObjectInfo` is a significant bottleneck when listing objects.
Reduce the allocations for a significant speedup.
https://github.com/minio/sio/pull/40
```
λ benchcmp before.txt after.txt
benchmark old ns/op new ns/op delta
Benchmark_decryptObjectInfo-32 24260928 808656 -96.67%
benchmark old MB/s new MB/s speedup
Benchmark_decryptObjectInfo-32 0.04 1.24 31.00x
benchmark old allocs new allocs delta
Benchmark_decryptObjectInfo-32 75112 48996 -34.77%
benchmark old bytes new bytes delta
Benchmark_decryptObjectInfo-32 287694772 4228076 -98.53%
```
In `(*cacheObjects).GetObjectNInfo` copy the metadata before spawning a goroutine.
Clean up a few map[string]string copies as well, reducing allocs and simplifying the code.
Fixes#10426
Currently when connections to vault fail, client
perpetually retries this leads to assumptions that
the server has issues and masks the problem.
Re-purpose *crypto.Error* type to send appropriate
errors back to the client.
This commit allows the MinIO server to parse the metadata if:
- either the `X-Minio-Internal-Server-Side-Encryption-S3-Key-Id`
and the `X-Minio-Internal-Server-Side-Encryption-S3-Kms-Sealed-Key`
entries are present.
- or *both* headers are not present.
This is in service to support a K/V data key store.
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
This commit adds two functions for sealing/unsealing the
etag (a.k.a. content MD5) in case of SSE single-part upload.
Sealing the ETag is neccessary in case of SSE-S3 to preserve
the security guarantees. In case of SSE-S3 AWS returns the
content-MD5 of the plaintext object as ETag. However, we
must not store the MD5 of the plaintext for encrypted objects.
Otherwise it becomes possible for an attacker to detect
equal/non-equal encrypted objects. Therefore we encrypt
the ETag before storing on the backend. But we only need
to encrypt the ETag (content-MD5) if the client send it -
otherwise the client cannot verify it anyway.
This commit adds two functions for removing
confidential information - like SSE-C keys -
from HTTP headers / object metadata.
This creates a central point grouping all
headers/entries which must be filtered / removed.
See also https://github.com/minio/minio/pull/6489#discussion_r219797993
of #6489
* crypto: add support for parsing SSE-C/SSE-S3 metadata
This commit adds support for detecting and parsing
SSE-C/SSE-S3 object metadata. With the `IsEncrypted`
functions it is possible to determine whether an object
seems to be encrypted. With the `ParseMetadata` functions
it is possible to validate such metadata and extract the
SSE-C/SSE-S3 related values.
It also fixes some naming issues.
* crypto: add functions for creating SSE object metadata
This commit adds functions for creating SSE-S3 and
SSE-C metadata. It also adds a `CreateMultipartMetadata`
for creating multipart metadata.
For all functions unit tests are included.
