This (big!) patch adds support for client side encryption in AWS S3,
with keys managed by AWS-KMS.
Read the documentation in encryption.md very, very carefully before
use and consider it unstable.
S3-CSE is enabled in the existing configuration option
"fs.s3a.server-side-encryption-algorithm":
fs.s3a.server-side-encryption-algorithm=CSE-KMS
fs.s3a.server-side-encryption.key=<KMS_KEY_ID>
You cannot enable CSE and SSE in the same client, although
you can still enable a default SSE option in the S3 console.
* Filesystem list/get status operations subtract 16 bytes from the length
of all files >= 16 bytes long to compensate for the padding which CSE
adds.
* The SDK always warns about the specific algorithm chosen being
deprecated. It is critical to use this algorithm for ranged
GET requests to work (i.e. random IO). Ignore.
* Unencrypted files CANNOT BE READ.
The entire bucket SHOULD be encrypted with S3-CSE.
* Uploading files may be a bit slower as blocks are now
written sequentially.
* The Multipart Upload API is disabled when S3-CSE is active.
Contributed by Mehakmeet Singh
f813554769