1 files changed, 146 insertions, 0 deletions
diff --git a/ready_se/google/keymint/KM300/Applet/src/com/android/javacard/keymaster/KMByteTag.java b/ready_se/google/keymint/KM300/Applet/src/com/android/javacard/keymaster/KMByteTag.java
new file mode 100644
index 0000000..5f7231f
--- /dev/null
+++ b/ready_se/google/keymint/KM300/Applet/src/com/android/javacard/keymaster/KMByteTag.java
@@ -0,0 +1,146 @@
+/*
+ * Copyright(C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.javacard.keymaster;
+
+import javacard.framework.ISO7816;
+import javacard.framework.ISOException;
+import javacard.framework.Util;
+
+/**
+ * KMByteTag represents BYTES Tag Type from android keymaster hal specifications. The tag value of
+ * this tag is the KMByteBlob pointer i.e. offset of KMByteBlob in memory heap. struct{byte
+ * TAG_TYPE; short length; struct{short BYTES_TAG; short tagKey; short blobPtr}}
+ */
+public class KMByteTag extends KMTag {
+
+  private static KMByteTag prototype;
+
+  private KMByteTag() {}
+
+  private static KMByteTag proto(short ptr) {
+    if (prototype == null) {
+      prototype = new KMByteTag();
+    }
+    KMType.instanceTable[KM_BYTE_TAG_OFFSET] = ptr;
+    return prototype;
+  }
+
+  // pointer to an empty instance used as expression
+  public static short exp() {
+    short blobPtr = KMByteBlob.exp();
+    short ptr = instance(TAG_TYPE, (short) 6);
+    Util.setShort(heap, (short) (ptr + TLV_HEADER_SIZE), BYTES_TAG);
+    Util.setShort(heap, (short) (ptr + TLV_HEADER_SIZE + 2), INVALID_TAG);
+    Util.setShort(heap, (short) (ptr + TLV_HEADER_SIZE + 4), blobPtr);
+    return ptr;
+  }
+
+  public static short instance(short key, short byteBlob) {
+    if (!validateKey(key, byteBlob)) {
+      ISOException.throwIt(ISO7816.SW_DATA_INVALID);
+    }
+    if (heap[byteBlob] != BYTE_BLOB_TYPE) {
+      ISOException.throwIt(ISO7816.SW_DATA_INVALID);
+    }
+    short ptr = instance(TAG_TYPE, (short) 6);
+    Util.setShort(heap, (short) (ptr + TLV_HEADER_SIZE), BYTES_TAG);
+    Util.setShort(heap, (short) (ptr + TLV_HEADER_SIZE + 2), key);
+    Util.setShort(heap, (short) (ptr + TLV_HEADER_SIZE + 4), byteBlob);
+    return ptr;
+  }
+
+  public static KMByteTag cast(short ptr) {
+    if (heap[ptr] != TAG_TYPE) {
+      ISOException.throwIt(ISO7816.SW_CONDITIONS_NOT_SATISFIED);
+    }
+    if (Util.getShort(heap, (short) (ptr + TLV_HEADER_SIZE)) != BYTES_TAG) {
+      ISOException.throwIt(ISO7816.SW_CONDITIONS_NOT_SATISFIED);
+    }
+    return proto(ptr);
+  }
+
+  private static boolean validateKey(short key, short byteBlob) {
+    short valueLen = KMByteBlob.cast(byteBlob).length();
+    switch (key) {
+      case ATTESTATION_APPLICATION_ID:
+        if (valueLen > MAX_ATTESTATION_APP_ID_SIZE) {
+          return false;
+        }
+        break;
+      case CERTIFICATE_SUBJECT_NAME:
+        {
+          if (valueLen > KMConfigurations.MAX_SUBJECT_DER_LEN) {
+            return false;
+          }
+          KMAsn1Parser asn1Decoder = KMAsn1Parser.instance();
+          asn1Decoder.validateDerSubject(byteBlob);
+        }
+        break;
+      case APPLICATION_ID:
+      case APPLICATION_DATA:
+        if (valueLen > MAX_APP_ID_APP_DATA_SIZE) {
+          return false;
+        }
+        break;
+      case ATTESTATION_CHALLENGE:
+        if (valueLen > MAX_ATTESTATION_CHALLENGE_SIZE) {
+          return false;
+        }
+        break;
+      case ATTESTATION_ID_BRAND:
+      case ATTESTATION_ID_DEVICE:
+      case ATTESTATION_ID_PRODUCT:
+      case ATTESTATION_ID_SERIAL:
+      case ATTESTATION_ID_IMEI:
+      case ATTESTATION_ID_SECOND_IMEI:
+      case ATTESTATION_ID_MEID:
+      case ATTESTATION_ID_MANUFACTURER:
+      case ATTESTATION_ID_MODEL:
+        if (valueLen > KMConfigurations.MAX_ATTESTATION_IDS_SIZE) {
+          return false;
+        }
+        break;
+      case ROOT_OF_TRUST:
+      case NONCE:
+        break;
+      default:
+        return false;
+    }
+    return true;
+  }
+
+  public short getKey() {
+    return Util.getShort(
+        heap, (short) (KMType.instanceTable[KM_BYTE_TAG_OFFSET] + TLV_HEADER_SIZE + 2));
+  }
+
+  public short getTagType() {
+    return KMType.BYTES_TAG;
+  }
+
+  public short getValue() {
+    return Util.getShort(
+        heap, (short) (KMType.instanceTable[KM_BYTE_TAG_OFFSET] + TLV_HEADER_SIZE + 4));
+  }
+
+  public short length() {
+    short blobPtr =
+        Util.getShort(
+            heap, (short) (KMType.instanceTable[KM_BYTE_TAG_OFFSET] + TLV_HEADER_SIZE + 4));
+    return KMByteBlob.cast(blobPtr).length();
+  }
+}