com_android_server_PersistentDataBlockService.cpp revision c90ca48a7c5981f1ebcb40ccab6e2ebbafe4c669 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <android_runtime/AndroidRuntime.h>
18#include <JNIHelp.h>
19#include <jni.h>
20#include <ScopedUtfChars.h>
21
22#include <utils/misc.h>
23#include <sys/ioctl.h>
24#include <sys/mount.h>
25#include <utils/Log.h>
26
27
28#include <inttypes.h>
29#include <fcntl.h>
30#include <errno.h>
31#include <string.h>
32
33namespace android {
34
35    uint64_t get_block_device_size(int fd)
36    {
37        uint64_t size = 0;
38        int ret;
39
40        ret = ioctl(fd, BLKGETSIZE64, &size);
41
42        if (ret)
43            return 0;
44
45        return size;
46    }
47
48    int wipe_block_device(int fd)
49    {
50        uint64_t range[2];
51        int ret;
52        uint64_t len = get_block_device_size(fd);
53
54        range[0] = 0;
55        range[1] = len;
56
57        if (range[1] == 0)
58            return 0;
59
60        ret = ioctl(fd, BLKSECDISCARD, &range);
61        if (ret < 0) {
62            ALOGE("Something went wrong secure discarding block: %s\n", strerror(errno));
63            range[0] = 0;
64            range[1] = len;
65            ret = ioctl(fd, BLKDISCARD, &range);
66            if (ret < 0) {
67                ALOGE("Discard failed: %s\n", strerror(errno));
68                return -1;
69            } else {
70                ALOGE("Wipe via secure discard failed, used non-secure discard instead\n");
71                return 0;
72            }
73
74        }
75
76        return ret;
77    }
78
79    static jlong com_android_server_PersistentDataBlockService_getBlockDeviceSize(JNIEnv *env, jclass, jstring jpath)
80    {
81        ScopedUtfChars path(env, jpath);
82        int fd = open(path.c_str(), O_RDONLY);
83
84        if (fd < 0)
85            return 0;
86
87        return get_block_device_size(fd);
88    }
89
90    static int com_android_server_PersistentDataBlockService_wipe(JNIEnv *env, jclass, jstring jpath) {
91        ScopedUtfChars path(env, jpath);
92        int fd = open(path.c_str(), O_WRONLY);
93
94        if (fd < 0)
95            return 0;
96
97        return wipe_block_device(fd);
98    }
99
100    static JNINativeMethod sMethods[] = {
101         /* name, signature, funcPtr */
102        {"nativeGetBlockDeviceSize", "(Ljava/lang/String;)J", (void*)com_android_server_PersistentDataBlockService_getBlockDeviceSize},
103        {"nativeWipe", "(Ljava/lang/String;)I", (void*)com_android_server_PersistentDataBlockService_wipe},
104    };
105
106    int register_android_server_PersistentDataBlockService(JNIEnv* env)
107    {
108        return jniRegisterNativeMethods(env, "com/android/server/PersistentDataBlockService",
109                                        sMethods, NELEM(sMethods));
110    }
111
112} /* namespace android */