SWW_APPS: an app's Core Rule Set fixes apply only to the hostnames that serve it (closes #220)

Each app's fixes are one .conf file and one entry in apps. They apply
only while Inspect has set the app's transaction variable, such as
tx.app_gitea. SWW_APPS names each hostname's apps. A hostname gets only
its apps' fixes; while SWW_APPS is unset, every hostname gets every
app's fixes.

A hostname in SWW_APPS that is not a DNS name, such as *.example.com,
stops the start. Unset, SWW_APPS is logged at start as null; set
empty, as "".

Model: opus-5-5

internal/coreruleset/nextcloud_test.go

@@ -51,6 +51,66 @@ const (
 // nextcloudOther is a JSON field no exclusion names.
 const nextcloudOther = `{"other":"python3"}`
 
+// nextcloud is Nextcloud's name in SWW_APPS.
+const nextcloud = "nextcloud"
+
+func TestNextcloudFixesApplyOnlyToAHostnameThatServesNextcloud(t *testing.T) {
+	t.Parallel()
+
+	crs := servingApps(t, map[string][]string{
+		giteaHost: {gitea}, otherHost: {nextcloud},
+	})
+
+	// A search, which only Nextcloud's fixes let through.
+	search := get(nextcloudUsers + "?search=python3")
+
+	wantResult(t, crs, withHost(search, otherHost), coreruleset.Result{})
+	wantResult(t, crs, withHost(search, giteaHost), matched(932260))
+}
+
+func TestNextcloudWebDAVMethodsPassOnlyOnHostnamesThatServeNextcloud(t *testing.T) {
+	t.Parallel()
+
+	crs := servingApps(t, map[string][]string{
+		giteaHost: {gitea}, otherHost: {nextcloud},
+	})
+
+	// Listing a folder, as the sync client does.
+	list := request{nextcloudPropFind, nextcloudFiles, nil}
+
+	wantResult(t, crs, withHost(list, otherHost), coreruleset.Result{})
+	wantResult(t, crs, withHost(list, giteaHost), matched(911100))
+
+	// Making a calendar, as a CalDAV client does.
+	calendar := request{nextcloudMkcalendar, nextcloudCalendars + "work/", nil}
+
+	wantResult(t, crs, withHost(calendar, otherHost), coreruleset.Result{})
+	wantResult(t, crs, withHost(calendar, giteaHost), matched(911100))
+}
+
+func TestNextcloudPasswordInValuePassesOnlyOnHostnamesThatServeNextcloud(t *testing.T) {
+	t.Parallel()
+
+	crs := shared(t, coreruleset.Params{
+		ParanoiaLevel: 1, DisabledRules: defaultDisabledRules, BodyLimit: bodyLimit,
+		Apps: map[string][]string{giteaHost: {gitea}, otherHost: {nextcloud}},
+	})
+
+	// A password that only the phase 2 rule 900127 lets through.
+	r := request{http.MethodPut, nextcloudUsers + "/alice", []string{formData}}
+	body := "key=password&value=" + url.QueryEscape("' OR '1'='1")
+
+	got, _ := inspectBody(t, crs, withHost(r, otherHost), body)
+	if got.Score >= nextcloudThreshold {
+		t.Errorf("PUT %s %s on %s refused: %+v", r.target, body, otherHost, got)
+	}
+
+	got, _ = inspectBody(t, crs, withHost(r, giteaHost), body)
+	if got.Score < nextcloudThreshold {
+		t.Errorf("PUT %s %s on %s let through: %+v", r.target, body, giteaHost, got)
+	}
+}
+
 // nextcloudQueryFields are the query fields that skip 930120, 932120, 932250
 // and 932260, each on a path where it skips them, ending in "=".
 //