Files
pixa/internal/signature/quality_fit_test.go
T
sneak 306e075b5c
check / check (push) Failing after 2m18s
Test that the URL signature covers quality and fit (closes #60)
Add Quality and FitMode to signature.Request, not yet part of the
signed data, and tests that a signature for quality 85 and fit cover is
refused when replayed with another quality or fit: one against
Signer.Verify, one through the image route. The route test also sends
the same signature with no q or fit and with q=85&fit=cover, which must
both pass, and sends URLs built by imgcache.Service.GenerateSignedURL.

The replay cases fail until the next commit.

Model: opus-4-8 (implementation); opus-5-5 (rework)
2026-09-28 10:22:53 +00:00

69 lines
1.8 KiB
Go

package signature_test
import (
"errors"
"testing"
"time"
"sneak.berlin/go/pixa/internal/signature"
)
// signedQualityFitRequest returns a request signed for quality 85 and fit
// mode "cover", the effective defaults the handler applies before
// verification.
func signedQualityFitRequest(signer *signature.Signer) *signature.Request {
req := &signature.Request{
SourceHost: testHost,
SourcePath: testPath,
Width: 800,
Height: 600,
Format: testFormatWebP,
Quality: 85,
FitMode: testFitCover,
Expires: time.Now().Add(1 * time.Hour),
}
req.Signature = signer.Sign(req)
return req
}
// TestSigner_Verify_QualityAndFitAreSigned proves that quality and fit are
// covered by the signature: a URL signed for one quality or fit mode must
// not verify when replayed with a different quality or fit mode. This is the
// amplification vector from the issue — one signed URL replayed across many
// quality and fit values yields many unauthorized cache entries and
// transcodes — so it must be rejected.
func TestSigner_Verify_QualityAndFitAreSigned(t *testing.T) {
t.Parallel()
signer := signature.New("test-secret-key")
cases := []struct {
name string
tamper func(r *signature.Request)
}{
{
name: "replayed with different quality",
tamper: func(r *signature.Request) { r.Quality = 40 },
},
{
name: "replayed with different fit mode",
tamper: func(r *signature.Request) { r.FitMode = testFitContain },
},
}
for _, tt := range cases {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
req := signedQualityFitRequest(signer)
tt.tamper(req)
err := signer.Verify(req)
if !errors.Is(err, signature.ErrInvalid) {
t.Errorf("Verify() = %v, want %v", err, signature.ErrInvalid)
}
})
}
}