This commit fixes a DoS vulnerability for certain APIs using
signature V4 by verifying the content-md5 and/or content-sha56 of
the request body in a streaming mode.
The issue was caused by reading the entire body of the request into
memory to verify the content-md5 or content-sha56 checksum if present.
The vulnerability could be exploited by either replaying a V4 request
(in the 15 min time frame) or sending a V4 presigned request with a
large body.
This commit fixes a DoS vulnerability in the
request authentication. The root cause is an 'unlimited'
read-into-RAM from the request body.
Since this read happens before the request authentication
is verified the vulnerability can be exploit without any
access privileges.
This commit limits the size of the request body to 3 MB.
This is about the same size as AWS. The limit seems to be
between 1.6 and 3.2 MB - depending on the AWS machine which
is handling the request.
- remove old bucket policy handling
- add new policy handling
- add new policy handling unit tests
This patch brings support to bucket policy to have more control not
limiting to anonymous. Bucket owner controls to allow/deny any rest
API.
For example server side encryption can be controlled by allowing
PUT/GET objects with encryptions including bucket owner.
This change fixes an authentication bypass attack against the
minio Admin-API. Therefore the Admin-API rejects now all types of
requests except valid signature V2 and signature V4 requests - this
includes signature V2/V4 pre-signed requests.
Fixes#5411
x-amz-content-sha256 can be optional for any AWS signature v4
requests, make sure to skip sha256 calculation when payload
checksum is not set.
Here is the overall expected behavior
** Signed request **
- X-Amz-Content-Sha256 is set to 'empty' or some 'value' or its
not 'UNSIGNED-PAYLOAD'- use it to validate the incoming payload.
- X-Amz-Content-Sha256 is set to 'UNSIGNED-PAYLOAD' - skip checksum verification
- X-Amz-Content-Sha256 is not set we use emptySHA256
** Presigned request **
- X-Amz-Content-Sha256 is set to 'empty' or some 'value' or its
not 'UNSIGNED-PAYLOAD'- use it to validate the incoming payload
- X-Amz-Content-Sha256 is set to 'UNSIGNED-PAYLOAD' - skip checksum verification
- X-Amz-Content-Sha256 is not set we use 'UNSIGNED-PAYLOAD'
Fixes#5339
The following commit f44f2e341c
fix was incomplete and we still had presigned URLs printing
in query strings in wrong fashion.
This PR fixes this properly. Avoid double encoding
percent encoded strings such as
`s3%!!(MISSING)A(MISSING)`
Print properly as json encoded.
`s3%3AObjectCreated%3A%2A`
We can't use Content-Encoding to verify if `aws-chunked` is set
or not. Just use 'streaming' signature header instead.
While this is considered mandatory, on the contrary aws-sdk-java
doesn't set this value
http://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html
```
Set the value to aws-chunked.
```
We will relax it and behave appropriately. Also this PR supports
saving custom encoding after trimming off the `aws-chunked`
parameter.
Fixes#3983
Content-Encoding is set to "aws-chunked" which is an S3 specific
API value which is no meaning for an object. This is how S3
behaves as well for a streaming signature uploaded object.
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.
Golang HTTP client automatically detects content-type but
for S3 clients this content-type might be incorrect or
might misbehave.
For example:
```
Content-Type: text/xml; charset=utf-8
```
Should be
```
Content-Type: application/xml
```
Allow this to be set properly.