Add a HIDL-based keystore_get variant

Create a "keystore_get" library that uses the HIDL path insted
of using binder directly.

Bug: 34603782
Test: Able to connect to wifi passpoint networks.
Change-Id: I0f545ea104e3f27bebd262bc5a2e79f6b517c972
diff --git a/keystore-engine/Android.mk b/keystore-engine/Android.mk
index 2264390..3041aa3 100644
--- a/keystore-engine/Android.mk
+++ b/keystore-engine/Android.mk
@@ -42,7 +42,7 @@
 
 # This builds a variant of libkeystore-engine that uses a HIDL HAL
 # owned by the WiFi user to perform signing operations.
-LOCAL_MODULE := libkeystore-engine-wifi
+LOCAL_MODULE := libkeystore-engine-wifi-hidl
 
 LOCAL_SRC_FILES := \
 	android_engine.cpp \
diff --git a/keystore-engine/keystore_backend_binder.cpp b/keystore-engine/keystore_backend_binder.cpp
index 181bd65..dce8242 100644
--- a/keystore-engine/keystore_backend_binder.cpp
+++ b/keystore-engine/keystore_backend_binder.cpp
@@ -54,7 +54,7 @@
         return -1;
     }
 
-    *reply = reply_vec.data();
+    *reply = reply_vec.releaseData();
     *reply_len = reply_vec.size();
     return 0;
 }
@@ -76,7 +76,7 @@
         return -1;
     }
 
-    *pubkey = pubkey_vec.data();
+    *pubkey = pubkey_vec.releaseData();
     *pubkey_len = pubkey_vec.size();
     return 0;
 }
diff --git a/keystore-engine/keystore_backend_hidl.cpp b/keystore-engine/keystore_backend_hidl.cpp
index b791afa..37ad9a1 100644
--- a/keystore-engine/keystore_backend_hidl.cpp
+++ b/keystore-engine/keystore_backend_hidl.cpp
@@ -38,9 +38,8 @@
     }
 
     sp<IKeystore> service = IKeystore::getService();
-
     if (service == NULL) {
-        ALOGE("could not contact keystore");
+        ALOGE("could not contact keystore HAL");
         return -1;
     }
 
@@ -66,9 +65,8 @@
     }
 
     sp<IKeystore> service = IKeystore::getService();
-
     if (service == NULL) {
-        ALOGE("could not contact keystore");
+        ALOGE("could not contact keystore HAL");
         return -1;
     }
 
diff --git a/keystore/Android.mk b/keystore/Android.mk
index 500c2f6..b379151 100644
--- a/keystore/Android.mk
+++ b/keystore/Android.mk
@@ -146,6 +146,28 @@
 LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
 include $(BUILD_SHARED_LIBRARY)
 
+# Library for keystore clients using the WiFi HIDL interface
+include $(CLEAR_VARS)
+LOCAL_CFLAGS := -Wall -Wextra -Werror
+LOCAL_SRC_FILES := \
+	keystore_get_wifi_hidl.cpp
+LOCAL_SHARED_LIBRARIES := \
+	android.system.wifi.keystore@1.0 \
+	libbase \
+	libhidlbase \
+	libhidltransport \
+	liblog \
+	libutils
+LOCAL_MODULE_CLASS := SHARED_LIBRARIES
+LOCAL_MODULE := libkeystore-wifi-hidl
+LOCAL_MODULE_TAGS := optional
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
+LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
+LOCAL_CLANG := true
+LOCAL_SANITIZE := integer
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
+include $(BUILD_SHARED_LIBRARY)
+
 # Library for unit tests
 include $(CLEAR_VARS)
 ifeq ($(USE_32_BIT_KEYSTORE), true)
diff --git a/keystore/keystore_get_wifi_hidl.cpp b/keystore/keystore_get_wifi_hidl.cpp
new file mode 100644
index 0000000..971b19d
--- /dev/null
+++ b/keystore/keystore_get_wifi_hidl.cpp
@@ -0,0 +1,60 @@
+/* Copyright 2017 The Android Open Source Project
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
+
+#include <android-base/logging.h>
+#include <android/system/wifi/keystore/1.0/IKeystore.h>
+
+#include <keystore/keystore_get.h>
+
+using namespace android;
+
+using android::hardware::hidl_string;
+using android::hardware::hidl_vec;
+using android::hardware::Return;
+using android::sp;
+using android::system::wifi::keystore::V1_0::IKeystore;
+
+ssize_t keystore_get(const char *key, size_t keyLength, uint8_t** value) {
+    if (key == NULL || keyLength == 0 || value == NULL) {
+        ALOGE("Null pointer argument passed");
+        return -1;
+    }
+
+    sp<IKeystore> service = IKeystore::getService();
+    if (service == NULL) {
+        ALOGE("could not contact keystore HAL");
+        return -1;
+    }
+
+    ssize_t return_size;
+    bool success = false;
+    auto cb = [&](IKeystore::KeystoreStatusCode status, hidl_vec<uint8_t> returnedValue) {
+        if (status == IKeystore::KeystoreStatusCode::SUCCESS) {
+            return_size = returnedValue.size();
+            *value = returnedValue.releaseData();
+            success = true;
+        }
+    };
+
+    Return<void> ret = service->getBlob(hidl_string(key, keyLength), cb);
+    return ret.isOk() && success ? return_size : -1;
+}