[gatekeeperd] return brute-force throttling information

Bug: 21118563
Change-Id: I13c6a44f61668be8b4c1fde8c84dcfebab84517c
diff --git a/gatekeeperd/SoftGateKeeper.h b/gatekeeperd/SoftGateKeeper.h
new file mode 100644
index 0000000..1ae45e6
--- /dev/null
+++ b/gatekeeperd/SoftGateKeeper.h
@@ -0,0 +1,127 @@
+/*
+ * Copyright 2015 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.
+ *
+ */
+
+#ifndef SOFT_GATEKEEPER_H_
+#define SOFT_GATEKEEPER_H_
+
+extern "C" {
+#include <openssl/rand.h>
+#include <crypto_scrypt.h>
+}
+
+#include <UniquePtr.h>
+#include <gatekeeper/gatekeeper.h>
+#include <iostream>
+#include <unordered_map>
+
+namespace gatekeeper {
+
+
+class SoftGateKeeper : public GateKeeper {
+public:
+    static const uint32_t SIGNATURE_LENGTH_BYTES = 32;
+
+    // scrypt params
+    static const uint64_t N = 16384;
+    static const uint32_t r = 8;
+    static const uint32_t p = 1;
+
+    static const int MAX_UINT_32_CHARS = 11;
+
+    SoftGateKeeper() {
+        key_.reset(new uint8_t[SIGNATURE_LENGTH_BYTES]);
+        memset(key_.get(), 0, SIGNATURE_LENGTH_BYTES);
+    }
+
+    virtual ~SoftGateKeeper() {
+    }
+
+    virtual bool GetAuthTokenKey(const uint8_t **auth_token_key,
+            uint32_t *length) const {
+        if (auth_token_key == NULL || length == NULL) return false;
+        *auth_token_key = const_cast<const uint8_t *>(key_.get());
+        *length = SIGNATURE_LENGTH_BYTES;
+        return true;
+    }
+
+    virtual void GetPasswordKey(const uint8_t **password_key, uint32_t *length) {
+        if (password_key == NULL || length == NULL) return;
+        *password_key = const_cast<const uint8_t *>(key_.get());
+        *length = SIGNATURE_LENGTH_BYTES;
+    }
+
+    virtual void ComputePasswordSignature(uint8_t *signature, uint32_t signature_length,
+            const uint8_t *, uint32_t, const uint8_t *password,
+            uint32_t password_length, salt_t salt) const {
+        if (signature == NULL) return;
+        crypto_scrypt(password, password_length, reinterpret_cast<uint8_t *>(&salt),
+                sizeof(salt), N, r, p, signature, signature_length);
+    }
+
+    virtual void GetRandom(void *random, uint32_t requested_length) const {
+        if (random == NULL) return;
+        RAND_pseudo_bytes((uint8_t *) random, requested_length);
+    }
+
+    virtual void ComputeSignature(uint8_t *signature, uint32_t signature_length,
+            const uint8_t *, uint32_t, const uint8_t *, const uint32_t) const {
+        if (signature == NULL) return;
+        memset(signature, 0, signature_length);
+    }
+
+    virtual uint64_t GetMillisecondsSinceBoot() const {
+        struct timespec time;
+        int res = clock_gettime(CLOCK_BOOTTIME, &time);
+        if (res < 0) return 0;
+        return (time.tv_sec * 1000) + (time.tv_nsec / 1000 / 1000);
+    }
+
+    virtual bool IsHardwareBacked() const {
+        return false;
+    }
+
+    virtual bool GetFailureRecord(uint32_t uid, secure_id_t user_id, failure_record_t *record) {
+        failure_record_t *stored = &failure_map_[uid];
+        if (user_id != stored->secure_user_id) {
+            stored->secure_user_id = user_id;
+            stored->last_checked_timestamp = 0;
+            stored->failure_counter = 0;
+        }
+        memcpy(record, stored, sizeof(*record));
+        return true;
+    }
+
+    virtual void ClearFailureRecord(uint32_t uid, secure_id_t user_id) {
+        failure_record_t *stored = &failure_map_[uid];
+        stored->secure_user_id = user_id;
+        stored->last_checked_timestamp = 0;
+        stored->failure_counter = 0;
+    }
+
+    virtual bool WriteFailureRecord(uint32_t uid, failure_record_t *record) {
+        failure_map_[uid] = *record;
+        return true;
+    }
+
+private:
+    UniquePtr<uint8_t> key_;
+    std::unordered_map<uint32_t, failure_record_t> failure_map_;
+};
+}
+
+#endif // SOFT_GATEKEEPER_H_
+