✨ Add TOFU continue option - fixes #6

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `left_margin` config option
 - Right margin for text (#1)
 - Desktop entry file
+- Option to continue anyway when cert doesn't match TOFU database
 
 ### Changed
 - Connection timeout is 15 seconds (was 5s)

NOTES.md

@@ -10,3 +10,4 @@
   - Filed [issue 25](https://gitlab.com/tslocum/cview/-/issues/25)
 - Modal styling messed up when wrapped - example occurence is the error modal for a long unsupported scheme URL
   - Filed [issue 26](https://gitlab.com/tslocum/cview/-/issues/26)
+  - Add some bold back into modal text after this is fixed

client/client.go

@@ -18,7 +18,7 @@ func Fetch(u string) (*gemini.Response, error) {
 	parsed, _ := url.Parse(u)
 	ok := handleTofu(resp.Cert, parsed.Port())
 	if !ok {
-		return nil, ErrTofu
+		return resp, ErrTofu
 	}
 	return resp, err
 }

client/tofu.go

@@ -104,3 +104,12 @@ func handleTofu(cert *x509.Certificate, port string) bool {
 	}
 	return false
 }
+
+// RemoveTofuEntry invalidates the TOFU entry in the database for the given cert and port.
+// This will make any cert for that domain valid.
+//
+// The port string can be empty, to indicate port 1965.
+func RemoveTofuEntry(cert *x509.Certificate, port string) {
+	tofuStore.Set(idKey(cert.Subject.CommonName, port), "")
+	tofuStore.WriteConfig()
+}

display/modals.go

@@ -1,6 +1,7 @@
 package display
 
 import (
+	"fmt"
 	"strconv"
 	"strings"
 
@@ -35,7 +36,6 @@ var inputCh = make(chan string)
 var inputModalText string // The current text of the input field in the modal
 
 var yesNoModal = cview.NewModal().
-	SetBackgroundColor(tcell.ColorPurple).
 	SetButtonBackgroundColor(tcell.ColorNavy).
 	SetButtonTextColor(tcell.ColorWhite).
 	SetTextColor(tcell.ColorWhite).
@@ -143,7 +143,26 @@ func Input(prompt string) (string, bool) {
 
 // YesNo displays a modal asking a yes-or-no question.
 func YesNo(prompt string) bool {
-	yesNoModal.SetText(prompt)
+	yesNoModal.SetText(prompt).SetBackgroundColor(tcell.ColorPurple)
+	tabPages.ShowPage("yesno")
+	tabPages.SendToFront("yesno")
+	App.SetFocus(yesNoModal)
+	App.Draw()
+
+	resp := <-yesNoCh
+	tabPages.SwitchToPage(strconv.Itoa(curTab))
+	return resp
+}
+
+// Tofu displays the TOFU warning modal.
+// It returns a bool indicating whether the user wants to continue.
+func Tofu(host string) bool {
+	// Reuses yesno modal, with error colour
+
+	yesNoModal.SetBackgroundColor(tcell.ColorMaroon)
+	yesNoModal.SetText(
+		fmt.Sprintf("%s's certificate has changed, possibly indicating an security issue. Are you sure you want to continue anyway?", host),
+	)
 	tabPages.ShowPage("yesno")
 	tabPages.SendToFront("yesno")
 	App.SetFocus(yesNoModal)

display/private.go

@@ -140,7 +140,7 @@ func setPage(p *structs.Page) {
 // The second returned item is a bool indicating if page content was displayed.
 // It returns false for Errors, other protocols, etc.
 func handleURL(u string) (string, bool) {
-	defer App.Draw() // Make sure modals get displayed
+	defer App.Draw() // Just in case
 
 	//logger.Log.Printf("Sent: %s", u)
 
@@ -178,7 +178,7 @@ func handleURL(u string) (string, bool) {
 		return "", false
 	}
 	if !strings.HasPrefix(u, "gemini") {
-		Error("Protocol Error", "Only [::b]gemini[::-] and [::b]http[::-] are supported. URL was "+u)
+		Error("Protocol Error", "Only gemini and HTTP are supported. URL was "+u)
 		bottomBar.SetText(tabMap[curTab].Url)
 		return "", false
 	}
@@ -195,7 +195,17 @@ func handleURL(u string) (string, bool) {
 	App.Draw()
 
 	res, err := client.Fetch(u)
-	if err != nil {
+	if err == client.ErrTofu {
+		if Tofu(parsed.Host) {
+			// They want to continue anyway
+			client.RemoveTofuEntry(res.Cert, parsed.Port())
+			return handleURL(u)
+		}
+		// They don't want to continue
+		// Set the bar back to original URL
+		bottomBar.SetText(tabMap[curTab].Url)
+		return "", false
+	} else if err != nil {
 		Error("URL Fetch Error", err.Error())
 		// Set the bar back to original URL
 		bottomBar.SetText(tabMap[curTab].Url)