feat: add URL check via FishFish

Author: cyb3rko

check/FishFish.go

@@ -0,0 +1,58 @@
+package check
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+type FishFishReport struct {
+	Category string `json:"category"`
+}
+
+const fishFishUrl = "https://api.fishfish.gg/v1/domains/%s"
+
+func HasFishFishWarning(urls []string, clientIdentifier string) bool {
+	userAgent := "Matrix Guardian Bot (" + clientIdentifier + ")"
+	for _, u := range urls {
+		if checkFfSingleUrl(u, userAgent) {
+			return true
+		}
+	}
+	return false
+}
+
+func checkFfSingleUrl(u string, userAgent string) bool {
+	if !strings.HasPrefix(u, "http") {
+		u = "http://" + u
+	}
+	parsedUrl, err := url.Parse(u)
+	if err != nil || parsedUrl.Host == "" {
+		return false
+	}
+	report := FishFishReport{}
+	responseCode, err := getJson(fmt.Sprintf(fishFishUrl, parsedUrl.Hostname()), userAgent, &report)
+	if err != nil || responseCode != 200 {
+		return false
+	}
+	return report.Category != "safe"
+}
+
+func getJson(u string, userAgent string, target *FishFishReport) (int, error) {
+	req, err := http.NewRequest("GET", u, nil)
+	req.Header = http.Header{
+		"Content-Type": []string{"application/json"},
+		"User-Agent":   []string{userAgent},
+	}
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return -1, err
+	}
+	defer func(Body io.ReadCloser) {
+		_ = Body.Close()
+	}(resp.Body)
+	return resp.StatusCode, json.NewDecoder(resp.Body).Decode(target)
+}

check/VirusTotal.go

@@ -9,14 +9,14 @@ import (
 func HasVirusTotalWarning(key string, urls []string) bool {
 	vtClient := vt.NewClient(key)
 	for _, url := range urls {
-		if checkSingleUrl(vtClient, url) {
+		if checkVtSingleUrl(vtClient, url) {
 			return true
 		}
 	}
 	return false
 }
 
-func checkSingleUrl(client *vt.Client, url string) bool {
+func checkVtSingleUrl(client *vt.Client, url string) bool {
 	urlId := base64.RawURLEncoding.EncodeToString([]byte(url))
 	report, err := client.Get(vt.URL("urls/%s", urlId))
 	if report == nil || err != nil {

main.go

@@ -154,6 +154,10 @@ func onProtectedRoomMessage(client *mautrix.Client, ctx context.Context, evt *ev
 		}
 		reg := regexp.MustCompile(filter.RegexUrl)
 		urls := reg.FindAllString(evt.Content.AsMessage().Body, -1)
+		if len(urls) == 0 {
+			// TODO send read indicator
+			return
+		}
 		if config.useUrlFilter && filter.IsUrlFiltered(database, urls) {
 			redactMessage(client, ctx, evt, "found blocklisted URL")
 			return
@@ -162,6 +166,10 @@ func onProtectedRoomMessage(client *mautrix.Client, ctx context.Context, evt *ev
 			redactMessage(client, ctx, evt, "found suspicious URL (VirusTotal)")
 			return
 		}
+		if config.useUrlCheckFf && check.HasFishFishWarning(urls, client.UserID.String()) {
+			redactMessage(client, ctx, evt, "found suspicious URL (FishFish)")
+			return
+		}
 		_, err := client.SendReaction(ctx, evt.RoomID, evt.ID, "🛡️")
 		if err != nil {
 			return