Add timing to reading operation; fix reading type 4 in multiple chunk…

…s of 256+
martinpaljak · Oct 26, 2023 · c7ed04a · c7ed04a
1 parent 7179c65
commit c7ed04a
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Showing 6 changed files with 46 additions and 31 deletions.
diff --git a/src/main/java/pro/javacard/nfc4pc/CLIOptions.java b/src/main/java/pro/javacard/nfc4pc/CLIOptions.java
@@ -8,7 +8,6 @@
 import java.io.IOException;
 import java.net.URI;
 import java.util.List;
-import java.util.Properties;
 import java.util.stream.Collectors;
 
 public abstract class CLIOptions {

diff --git a/src/main/java/pro/javacard/nfc4pc/NDEF.java b/src/main/java/pro/javacard/nfc4pc/NDEF.java
@@ -150,25 +150,43 @@ static Optional<byte[]> getType4(APDUBIBO bibo) {
                     // Capabilities
                     ResponseAPDU read = bibo.transceive(new CommandAPDU(0x00, 0xb0, 0x00, 0x00, 0x0F));
 
+                    // We always use short APDU-s
                     int maxReadSize = getShort(read.getData(), (short) 3);
+                    if (maxReadSize > 0x100) {
+                        log.warn("Max read size is {}, limiting to 256", maxReadSize);
+                        maxReadSize = 0x100;
+                    }
+
+                    // This DOES include the 2 byte header
                     int payloadSize = getShort(read.getData(), (short) 11);
 
                     ResponseAPDU selectDATA = bibo.transceive(new CommandAPDU(0x00, 0xA4, 0x00, 0x0C, HexUtils.hex2bin("e104")));
                     if (selectDATA.getSW() == 0x9000) {
                         ResponseAPDU len = bibo.transceive(new CommandAPDU(0x00, 0xb0, 0x00, 0x00, 0x02));
-                        int reportedLen = getShort(len.getData(), (short) 0);
-                        if ((reportedLen + 2) != payloadSize) {
-                            log.error("Warning: payload length mismatch");
-                        }
                         if (len.getSW() == 0x9000) {
-                            final byte[] payload;
-                            if (reportedLen > maxReadSize) { // XXX: assumes that not that big
-                                byte[] chunk1 = bibo.transceive(new CommandAPDU(0x00, 0xb0, 0x00, 0x02, maxReadSize)).getData();
-                                byte[] chunk2 = bibo.transceive(new CommandAPDU(0x00, 0xb0, 0x00, maxReadSize + 2, reportedLen - maxReadSize)).getData();
-                                payload = concatenate(chunk1, chunk2);
-                            } else {
-                                payload = bibo.transceive(new CommandAPDU(0x00, 0xb0, 0x00, 0x02, reportedLen)).getData();
+                            // 2 byte header contains the payload length AFTER the header
+                            int reportedLen = getShort(len.getData(), (short) 0);
+                            if ((reportedLen + 2) != payloadSize) {
+                                log.error("Warning: payload length mismatch");
+                            }
+
+                            ByteArrayOutputStream bos = new ByteArrayOutputStream();
+                            int offset;
+                            int i;
+                            // Limit up to 10 reads
+                            for (offset = 2, i = 0; offset < payloadSize && i < 10; i++) {
+                                int left = payloadSize - offset;
+
+                                ResponseAPDU readResponse = bibo.transceive(new CommandAPDU(0x00, 0xb0, offset >> 8, offset, Math.min(left, maxReadSize)));
+                                if (readResponse.getSW() != 0x9000) {
+                                    log.error("Read returned: {}", readResponse.getSW());
+                                    return Optional.empty();
+                                }
+                                byte[] chunk = readResponse.getData();
+                                offset += chunk.length;
+                                bos.writeBytes(chunk);
                             }
+                            byte[] payload = bos.toByteArray();
                             log.info("Payload: " + HexUtils.bin2hex(payload));
                             return Optional.of(payload);
                         }

diff --git a/src/main/java/pro/javacard/nfc4pc/NFC4PC.java b/src/main/java/pro/javacard/nfc4pc/NFC4PC.java
@@ -9,8 +9,6 @@
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.net.URLEncoder;
-import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.LinkedHashMap;
 import java.util.concurrent.ScheduledFuture;

diff --git a/src/main/java/pro/javacard/nfc4pc/NFCReader.java b/src/main/java/pro/javacard/nfc4pc/NFCReader.java
@@ -12,6 +12,7 @@
 import javax.smartcardio.CardTerminal;
 import java.io.IOException;
 import java.net.URI;
+import java.time.Duration;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -43,7 +44,7 @@ public NFCReader(TapProcessor processor) {
     }
 
     // This is a fun exercise, we have a thread per reader and use the thread name for logging as well as reader access.
-    private  void onReaderThread(String name, Runnable r) {
+    private void onReaderThread(String name, Runnable r) {
         readerThreads.computeIfAbsent(name, (n) -> Executors.newSingleThreadExecutor(new NamedReaderThreadFactory(n))).submit(r);
     }
 
@@ -110,6 +111,8 @@ private void tryToRead() {
             c.beginExclusive(); // Use locking, as this is short read
             // get UID
             APDUBIBO b = new APDUBIBO(CardBIBO.wrap(c));
+
+            long start = System.currentTimeMillis();
             var uid = NDEF.getUID(b);
             if (uid.isEmpty()) {
                 log.info("No UID, assuming not a supported contactless reader/device");
@@ -118,20 +121,22 @@ private void tryToRead() {
             }
             // Type 2 > Type 4
             var url = NDEF.getType2(b).or(() -> NDEF.getType4(b));
+            Duration readtime = Duration.ofMillis(System.currentTimeMillis() - start);
+
 
             String location = null;
             if (url.isPresent()) {
                 try {
                     // TODO: detect unknown payload. TODO: warn if smart poster
                     location = NDEF.msg2url(url.get());
-                    processor.onNFCTap(new NFCTapData(n, uid.get(), URI.create(location), null));
+                    processor.onNFCTap(new NFCTapData(n, uid.get(), URI.create(location), readtime, null));
                 } catch (IllegalArgumentException e) {
                     processor.onNFCTap(new NFCTapData(n, uid.get(), e));
                     return;
                     //notifyUser(n, "Could not parse message etc");
                 }
             } else {
-                processor.onNFCTap(new NFCTapData(n, uid.get(), null, null));
+                processor.onNFCTap(new NFCTapData(n, uid.get(), null, readtime, null));
             }
         } catch (BIBOException e) {
             // TODO: notify exclusively opened readers ?

diff --git a/src/main/java/pro/javacard/nfc4pc/NFCTapData.java b/src/main/java/pro/javacard/nfc4pc/NFCTapData.java
@@ -3,22 +3,23 @@
 import apdu4j.core.HexUtils;
 
 import java.net.URI;
+import java.time.Duration;
 
-public record NFCTapData(String reader, byte[] uid, URI url, Exception error) {
+public record NFCTapData(String reader, byte[] uid, URI url, Duration readtime, Exception error) {
     public NFCTapData(String reader, Exception error) {
-        this(reader, null, null, error);
+        this(reader, null, null, null, error);
     }
 
     public NFCTapData(String reader, byte[] uid, Exception error) {
-        this(reader, uid, null, error);
+        this(reader, uid, null, null, error);
     }
 
     public NFCTapData(String reader, byte[] uid, URI url) {
-        this(reader, uid, url, null);
+        this(reader, uid, url, null, null);
     }
 
     @Override
     public String toString() {
-        return String.format("TapData[reader=%s, uid=%s, url=%s, error=%s]", reader, HexUtils.bin2hex(uid), url, error);
+        return String.format("TapData[reader=%s, uid=%s, url=%s, readtime=%dms, error=%s]", reader, HexUtils.bin2hex(uid), url, readtime.toMillis(), error);
     }
 }
diff --git a/src/test/java/pro/javacard/nfc4pc/MiscTest.java b/src/test/java/pro/javacard/nfc4pc/MiscTest.java
@@ -1,17 +1,11 @@
 package pro.javacard.nfc4pc;
 
-import apdu4j.core.HexUtils;
-import com.payneteasy.tlv.BerTlvParser;
-import com.payneteasy.tlv.BerTlvs;
 import org.junit.jupiter.api.Test;
 
 public class MiscTest {
-
     @Test
-    public  void testSomething() {
-        byte[] v = HexUtils.hex2bin("0312D1010E55046B7962657270756E6B2E6E6574FE000000000000000000000000000000000000000000000000000000000000000000000000000000");
-        BerTlvParser parser = new BerTlvParser();
-        BerTlvs result = parser.parse(v);
-        System.out.println(result);
+    public void nothing() throws Exception {
+
     }
 }
+