cas: add CAS hal

Add CAS hal definitions and default service implementation.

bug: 22804304

Change-Id: I0a89608fe75c5f3c5e6888f9b771305742760707
diff --git a/cas/native/1.0/Android.bp b/cas/native/1.0/Android.bp
new file mode 100644
index 0000000..414fca7
--- /dev/null
+++ b/cas/native/1.0/Android.bp
@@ -0,0 +1,65 @@
+// This file is autogenerated by hidl-gen. Do not edit manually.
+
+filegroup {
+    name: "android.hardware.cas.native@1.0_hal",
+    srcs: [
+        "types.hal",
+        "IDescrambler.hal",
+    ],
+}
+
+genrule {
+    name: "android.hardware.cas.native@1.0_genc++",
+    tools: ["hidl-gen"],
+    cmd: "$(location hidl-gen) -o $(genDir) -Lc++-sources -randroid.hardware:hardware/interfaces -randroid.hidl:system/libhidl/transport android.hardware.cas.native@1.0",
+    srcs: [
+        ":android.hardware.cas.native@1.0_hal",
+    ],
+    out: [
+        "android/hardware/cas/native/1.0/types.cpp",
+        "android/hardware/cas/native/1.0/DescramblerAll.cpp",
+    ],
+}
+
+genrule {
+    name: "android.hardware.cas.native@1.0_genc++_headers",
+    tools: ["hidl-gen"],
+    cmd: "$(location hidl-gen) -o $(genDir) -Lc++-headers -randroid.hardware:hardware/interfaces -randroid.hidl:system/libhidl/transport android.hardware.cas.native@1.0",
+    srcs: [
+        ":android.hardware.cas.native@1.0_hal",
+    ],
+    out: [
+        "android/hardware/cas/native/1.0/types.h",
+        "android/hardware/cas/native/1.0/hwtypes.h",
+        "android/hardware/cas/native/1.0/IDescrambler.h",
+        "android/hardware/cas/native/1.0/IHwDescrambler.h",
+        "android/hardware/cas/native/1.0/BnHwDescrambler.h",
+        "android/hardware/cas/native/1.0/BpHwDescrambler.h",
+        "android/hardware/cas/native/1.0/BsDescrambler.h",
+    ],
+}
+
+cc_library_shared {
+    name: "android.hardware.cas.native@1.0",
+    defaults: ["hidl-module-defaults"],
+    generated_sources: ["android.hardware.cas.native@1.0_genc++"],
+    generated_headers: ["android.hardware.cas.native@1.0_genc++_headers"],
+    export_generated_headers: ["android.hardware.cas.native@1.0_genc++_headers"],
+    vendor_available: true,
+    shared_libs: [
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "liblog",
+        "libutils",
+        "libcutils",
+        "android.hardware.cas@1.0",
+    ],
+    export_shared_lib_headers: [
+        "libhidlbase",
+        "libhidltransport",
+        "libhwbinder",
+        "libutils",
+        "android.hardware.cas@1.0",
+    ],
+}
diff --git a/cas/native/1.0/IDescrambler.hal b/cas/native/1.0/IDescrambler.hal
new file mode 100644
index 0000000..459e5e3
--- /dev/null
+++ b/cas/native/1.0/IDescrambler.hal
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2017 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 android.hardware.cas.native@1.0;
+
+import android.hardware.cas@1.0::IDescramblerBase;
+
+/**
+ * IDescrambler is the native plugin API for descrambling operations.
+ */
+
+interface IDescrambler extends IDescramblerBase {
+    /**
+     * Descramble the data in a source SharedBuffer, described by an array of
+     * SubSample structures.
+     *
+     * @param scramblingControl an enumeration indicating the key that the subsamples
+     * were scrambled with.
+     * @param subSamples an array of SubSample structures describing the number of
+     * clear and scrambled bytes within each subsample.
+     * @param srcBuffer the SharedBuffer containing the source scrambled data.
+     * @param srcOffset the position where the source scrambled data starts at.
+     * @param dstBuffer the DestinationBuffer to hold the descrambled data.
+     * @param dstOffset the position where the descrambled data should start at.
+     *
+     * @return status the status of the call.
+     * @return bytesWritten number of bytes that have been successfully descrambled.
+     * @return detailedError a detailed message describing the error (if any).
+     */
+    descramble(ScramblingControl scramblingControl, vec<SubSample> subSamples,
+        SharedBuffer srcBuffer, uint64_t srcOffset, DestinationBuffer dstBuffer, uint64_t dstOffset)
+        generates(Status status, uint32_t bytesWritten, string detailedError);
+};
diff --git a/cas/native/1.0/types.hal b/cas/native/1.0/types.hal
new file mode 100644
index 0000000..a576d03
--- /dev/null
+++ b/cas/native/1.0/types.hal
@@ -0,0 +1,90 @@
+/**
+ * Copyright (C) 2017 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 android.hardware.cas.native@1.0;
+
+import android.hardware.cas@1.0::types;
+
+/**
+ * Enumerates the keys used to scramble the content.
+ */
+enum ScramblingControl : uint32_t {
+    UNSCRAMBLED = 0,
+    RESERVED    = 1,
+    EVENKEY     = 2,
+    ODDKEY      = 3,
+};
+
+/**
+ * A subsample consists of some number of bytes of clear (unscrambled)
+ * data followed by a number of bytes of scrambled data.
+ */
+struct SubSample {
+    uint32_t numBytesOfClearData;
+    uint32_t numBytesOfEncryptedData;
+};
+
+/**
+ * SharedBuffer describes a shared buffer which is defined by a heapBase, an
+ * offset and a size. The offset is relative to the shared memory base for the
+ * memory region identified by heapBase.
+ */
+struct SharedBuffer {
+    /**
+     * The shared memory base handle
+     */
+    memory heapBase;
+
+    /**
+     * The offset from the shared memory base
+     */
+    uint64_t offset;
+
+    /**
+     * The size of the shared buffer in bytes
+     */
+    uint64_t size;
+};
+
+/**
+ * A descrambling destination buffer can be either normal user-space shared
+ * memory for the non-secure descrambling case, or it can be a secure buffer
+ * which is referenced by a native-handle. The native handle is allocated
+ * by the vendor's buffer allocator.
+ */
+enum BufferType : uint32_t {
+    SHARED_MEMORY = 0,
+    NATIVE_HANDLE = 1,
+};
+
+struct DestinationBuffer {
+    /**
+     * The type of the buffer
+     */
+    BufferType type;
+
+    /**
+     * If type == SHARED_MEMORY, the descrambled data must be written
+     * to user-space non-secure shared memory.
+     */
+    SharedBuffer nonsecureMemory;
+
+    /**
+     * If type == NATIVE_HANDLE, the descrambled data must be written
+     * to secure memory referenced by the vendor's buffer allocator.
+     */
+    handle secureMemory;
+};