* fix(s3api): require space in v2 auth prefix
Problem: Signature V2 Authorization headers with a malformed algorithm token such as AWSX... are accepted as if they were AWS ... headers.
Root cause: validateV2AuthHeader checks HasPrefix("AWS") but then slices past an assumed trailing space, so an extra character after AWS is skipped and the rest is parsed as credentials.
Fix: Require the Authorization header to start with the exact AWS plus space prefix before parsing fields.
Reproduction: go test ./weed/s3api -run 'TestValidateV2AuthHeader/algorithm_prefix_without_space|TestDoesSignV2Match/malformed_auth_-_no_space_after_AWS' -count=1 fails before the fix because AWSXAKIA... is accepted.
Validation: go test ./weed/s3api -run 'TestValidateV2AuthHeader/algorithm_prefix_without_space|TestDoesSignV2Match/malformed_auth_-_no_space_after_AWS' -count=1; go test ./weed/s3api -count=1; git diff --check; git diff --cached --check
* Update weed/s3api/auth_signature_v2.go
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
---------
Co-authored-by: Chris Lu <chrislusf@users.noreply.github.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
see https://blog.aqwari.net/xml-schema-go/
1. go get aqwari.net/xml/cmd/xsdgen
2. Add EncodingType element for ListBucketResult in AmazonS3.xsd
3. xsdgen -o s3api_xsd_generated.go -pkg s3api AmazonS3.xsd
4. Remove empty Grantee struct in s3api_xsd_generated.go
5. Remove xmlns: sed s'/http:\/\/s3.amazonaws.com\/doc\/2006-03-01\/\ //' s3api_xsd_generated.go