Merge "Crypto changes for devices that don't write ext4 fs on wipe"

include/cutils/partition_utils.h

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2011, 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 __CUTILS_PARTITION_WIPED_H__
+#define __CUTILS_PARTITION_WIPED_H__
+
+__BEGIN_DECLS
+
+int partition_wiped(char *source);
+void erase_footer(const char *dev_path, long long size);
+
+__END_DECLS
+
+#endif /* __CUTILS_PARTITION_WIPED_H__ */

libcutils/Android.mk

@@ -110,7 +110,7 @@ else #!sim
 # ========================================================
 include $(CLEAR_VARS)
 LOCAL_MODULE := libcutils
-LOCAL_SRC_FILES := $(commonSources) ashmem-dev.c mq.c android_reboot.c uevent.c
+LOCAL_SRC_FILES := $(commonSources) ashmem-dev.c mq.c android_reboot.c partition_utils.c uevent.c
 
 ifeq ($(TARGET_ARCH),arm)
 LOCAL_SRC_FILES += arch-arm/memset32.S

libcutils/partition_utils.c

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2011, 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 <sys/types.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h> /* for BLKGETSIZE */
+#include <cutils/properties.h>
+
+static int only_one_char(char *buf, int len, char c)
+{
+    int i, ret;
+
+    ret = 1;
+    for (i=0; i<len; i++) {
+        if (buf[i] != c) {
+            ret = 0;
+            break;
+        }
+    }
+    return ret;
+}
+
+int partition_wiped(char *source)
+{
+    char buf[4096];
+    int fd, ret, wiped;
+
+    if ((fd = open(source, O_RDONLY)) < 0) {
+        return 0;
+    }
+
+    ret = read(fd, buf, sizeof(buf));
+    close(fd);
+
+    if (ret != sizeof(buf)) {
+        return 0;
+    }
+
+    /* Check for all zeros */
+    if (only_one_char(buf, sizeof(buf), 0)) {
+       return 1;
+    }
+
+    /* Check for all ones */
+    if (only_one_char(buf, sizeof(buf), 0xff)) {
+       return 1;
+    }
+
+    return 0;
+}
+