* 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>
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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>
* fix(s3api): fix AWS Signature V2 format and validation
* fix(s3api): Skip space after "AWS" prefix (+1 offset)
* test(s3api): add unit tests for Signature V2 authentication fix
* fix(s3api): simply comparing signatures
* validation for the colon extraction in expectedAuth
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Co-authored-by: chrislu <chris.lu@gmail.com>
Sergey Zinchenko