Files
multica/server/internal/storage/util_test.go
Bohan Jiang 424f67f7cb fix(security): normalize MIME type in isInlineContentType (#3050)
isInlineContentType is the security boundary that decides whether an
uploaded file is served with Content-Disposition: inline (renderable
in the document origin) or attachment. The SVG carve-out added in
#3023 to block stored-XSS via uploaded .svg only matched the exact
literal "image/svg+xml", so callers that supply "IMAGE/SVG+XML",
"image/svg+xml; charset=utf-8", or whitespace-padded variants would
still see disposition=inline. MIME type matching is case-insensitive
per RFC 2045 §5.1 and may carry parameters, so the safe thing is to
normalize at the boundary instead of trusting every caller.

Today both call sites (S3.Upload and LocalStorage.Serve) happen to
feed in the exact literal because the upload handler overrides .svg
to "image/svg+xml" before storage sees it, so this is defense-in-depth
rather than a live regression. Hardens the helper so any future caller
(including one that ever trusts a client-supplied Content-Type) stays
behind the same guard.

Co-authored-by: multica-agent <github@multica.ai>
2026-05-22 13:01:52 +08:00

44 lines
1.2 KiB
Go

package storage
import "testing"
func TestIsInlineContentType(t *testing.T) {
cases := []struct {
ct string
want bool
}{
{"image/png", true},
{"image/jpeg", true},
{"image/gif", true},
{"image/webp", true},
{"video/mp4", true},
{"audio/mpeg", true},
{"application/pdf", true},
// SVG must NOT render inline — it can carry executable script.
{"image/svg+xml", false},
// MIME types are case-insensitive (RFC 2045 §5.1) and may carry
// parameters. The SVG carve-out is a security boundary, so any
// variant that resolves to image/svg+xml must also be blocked.
{"IMAGE/SVG+XML", false},
{"Image/Svg+Xml", false},
{"image/svg+xml; charset=utf-8", false},
{"image/svg+xml;charset=utf-8", false},
{" image/svg+xml ", false},
// Normalization must not break the positive cases either.
{"IMAGE/PNG", true},
{"image/png; foo=bar", true},
{" application/pdf", true},
{"text/html", false},
{"application/octet-stream", false},
{"text/plain", false},
{"", false},
}
for _, tc := range cases {
if got := isInlineContentType(tc.ct); got != tc.want {
t.Errorf("isInlineContentType(%q) = %v, want %v", tc.ct, got, tc.want)
}
}
}