upload android base code part6

android/system/keymaster/android_keymaster_utils.cpp

@@ -0,0 +1,95 @@
+/*
+ * Copyright 2014 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.
+ */
+
+#include <keymaster/android_keymaster_utils.h>
+
+#include <keymaster/new>
+
+namespace keymaster {
+
+// Keymaster never manages enormous buffers, so anything particularly large is bad data or the
+// result of a bug.  We arbitrarily set a 16 MiB limit.
+const size_t kMaxDupBufferSize = 16 * 1024 * 1024;
+
+uint8_t* dup_buffer(const void* buf, size_t size) {
+    if (size >= kMaxDupBufferSize)
+        return nullptr;
+    uint8_t* retval = new (std::nothrow) uint8_t[size];
+    if (retval)
+        memcpy(retval, buf, size);
+    return retval;
+}
+
+int memcmp_s(const void* p1, const void* p2, size_t length) {
+    const uint8_t* s1 = static_cast<const uint8_t*>(p1);
+    const uint8_t* s2 = static_cast<const uint8_t*>(p2);
+    uint8_t result = 0;
+    while (length-- > 0)
+        result |= *s1++ ^ *s2++;
+    return result == 0 ? 0 : 1;
+}
+
+keymaster_error_t EcKeySizeToCurve(uint32_t key_size_bits, keymaster_ec_curve_t* curve) {
+    switch (key_size_bits) {
+    default:
+        return KM_ERROR_UNSUPPORTED_KEY_SIZE;
+
+    case 224:
+        *curve = KM_EC_CURVE_P_224;
+        break;
+
+    case 256:
+        *curve = KM_EC_CURVE_P_256;
+        break;
+
+    case 384:
+        *curve = KM_EC_CURVE_P_384;
+        break;
+
+    case 521:
+        *curve = KM_EC_CURVE_P_521;
+        break;
+    }
+
+    return KM_ERROR_OK;
+}
+
+keymaster_error_t EcCurveToKeySize(keymaster_ec_curve_t curve, uint32_t* key_size_bits) {
+    switch (curve) {
+    default:
+        return KM_ERROR_UNSUPPORTED_EC_CURVE;
+
+    case KM_EC_CURVE_P_224:
+        *key_size_bits = 224;
+        break;
+
+    case KM_EC_CURVE_P_256:
+        *key_size_bits = 256;
+        break;
+
+    case KM_EC_CURVE_P_384:
+        *key_size_bits = 384;
+        break;
+
+    case KM_EC_CURVE_P_521:
+        *key_size_bits = 521;
+        break;
+    }
+
+    return KM_ERROR_OK;
+}
+
+}  // namespace keymaster