taler-ios

commit 19b2485d7d51205eff6820191473ac7d05fa3afa
parent 7600dde63e872446d3a23858ce73cecdd6d536a7
Author: Marc Stibane <marc@taler.net>
Date:   Tue, 30 Jun 2026 08:34:40 +0200

limit talerURIs to 8k lenght (w.i.p.)

Diffstat:
M
TalerWallet1/Helper/TagEmulation.swift
 | 
3
++-
M
TalerWallet1/Helper/apdu.swift
 | 
19
+++++++++++++++----

2 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/TalerWallet1/Helper/TagEmulation.swift b/TalerWallet1/Helper/TagEmulation.swift
@@ -48,6 +48,7 @@ class TagEmulation: ObservableObject {
         // presentmentIntent.isValid to ensure the assertion remains active.
         var result = false
 
+        guard emulatedData.count < 8192 else { return false }
         do {
             if presentmentIntent == nil {
                 presentmentIntent = try await NFCPresentmentIntentAssertion.acquire()
@@ -108,7 +109,7 @@ class TagEmulation: ObservableObject {
     }
 
     private func eventStream(_ mySession: CardSession, data emulatedData: String) async throws {
-        let apdu = APDU(emulatedData)
+        let apdu = try APDU(emulatedData)
         // Iterate over events as the card session produces them.
         for try await event in mySession.eventStream {
 //            if presentmentIntent?.isValid ?? false {
diff --git a/TalerWallet1/Helper/apdu.swift b/TalerWallet1/Helper/apdu.swift
@@ -8,14 +8,22 @@
 import Foundation
 import os.log
 
+enum APDUError: Error {
+    case invalidStringValue
+}
+
 @MainActor
 class APDU {
-    let talerUri: String
+    let talerUri: String        // contains only ASCII, never Unicode
     nonisolated let logger = Logger(subsystem: "net.taler.gnu", category: "APDU")
     private var readCapabilityContainerCheck = false
 
-    init(_ talerUri: String) {
-        self.talerUri = talerUri
+    init(_ talerUri: String) throws {
+        if talerUri.count < 8192 {
+            self.talerUri = talerUri
+        } else {
+            throw APDUError.invalidStringValue
+        }
     }
 
     private var APDU_SELECT: Data {
@@ -204,8 +212,11 @@ class APDU {
             return A_OKAY
         } // 00a4000c02e104
 
+        // TODO: This only works for talerURIs < 256 bytes
+        // but they may be up to 8192 bytes long
+        // So we need to change to long header...
         let uriCount = talerUri.count
-        let ndefLen = UInt16(uriCount + 5)     // NDEF_RECORD_HEADER is 4 bytes
+        let ndefLen = UInt16(uriCount + 5)     // NDEF_RECORD_HEADER_SHORT + len + "U" + 0
         /// Fifth Command: Read the Length of the NDEF File     // 00b0 00 00 02
         if NDEF_READ_BINARY_NLEN == commandApdu {
             logger.info("NDEF_READ_BINARY_NLEN triggered. Our Response: length \(ndefLen) + A_OKAY")