Add Ext4 Tool

Change-Id: I23df2c8adbd31c100e0b28dcd23271f840af34d3
Signed-off-by: Seok Hong <seok85.hong@samsung.com>

diff --git a/server/CMakeLists.txt b/server/CMakeLists.txt
index d67cda9..94a688d 100644 (file)
--- a/server/CMakeLists.txt
+++ b/server/CMakeLists.txt
@@ -15,6 +15,7 @@
 #
 SET(SERVER_SRCS        main.cpp
                                server.cpp
+                               ext4-tool.cpp
                                secure-erase.cpp
                                internal-encryption.cpp
                                external-encryption.cpp

diff --git a/server/ext4-tool.cpp b/server/ext4-tool.cpp
new file mode 100644 (file)
index 0000000..783c084
--- /dev/null
+++ b/server/ext4-tool.cpp
@@ -0,0 +1,151 @@
+/*
+ *  Copyright (c) 2015 Samsung Electronics Co., Ltd All Rights Reserved
+ *
+ *  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 <fcntl.h>
+
+#include <string>
+#include <vector>
+
+#include <klay/filesystem.h>
+#include <klay/process.h>
+#include <klay/exception.h>
+#include <klay/audit/logger.h>
+
+#include "ext4-tool.h"
+
+namespace ode {
+
+#define ODE_SUPERBLOCK_OFFSET          1024
+#define ODE_SUPERBLOCK_SIZE                    1024
+#define ODE_EXT2_MIN_DESC_SIZE         32
+#define ODE_EXT2_MIN_BLOCK_LOG_SIZE    10      /* 1024 */
+#define ODE_EXT2_MIN_BLOCK_SIZE                (1 << ODE_EXT2_MIN_BLOCK_LOG_SIZE)
+
+static unsigned int divCeilSafely(unsigned int a, unsigned int b)
+{
+       if (!a)
+               return 0;
+
+       return ((a - 1) / b) + 1;
+}
+
+Ext4Tool::Ext4Tool(const std::string &src) :
+       source(src), totalBlockCount(0)
+{
+       unsigned int firstDataBlock = 0;
+       unsigned int blockSize = 0;
+       unsigned int blocksPerGroup = 0;
+       unsigned int clustersPerGroup = 0;
+       runtime::File device(source);
+
+       if (device.exists() == false)
+               throw runtime::Exception("Source doesn't exist");
+
+       device.open(O_RDONLY);
+
+       // read totalBlockCount
+       device.lseek(ODE_SUPERBLOCK_OFFSET +  4, SEEK_SET);
+       device.read(&totalBlockCount, 4);
+
+       // read firstDataBlock
+       device.lseek(ODE_SUPERBLOCK_OFFSET + 20, SEEK_SET);
+       device.read(&firstDataBlock, 4);
+
+       // read blockSize
+       device.lseek(ODE_SUPERBLOCK_OFFSET + 24, SEEK_SET);
+       device.read(&blockSize, 4);
+       blockSize = (ODE_EXT2_MIN_BLOCK_SIZE << blockSize);
+
+       // read blocksPerGroup
+       device.lseek(ODE_SUPERBLOCK_OFFSET + 32, SEEK_SET);
+       device.read(&blocksPerGroup, 4);
+
+       // read clustersPerGroup
+       device.lseek(ODE_SUPERBLOCK_OFFSET + 36, SEEK_SET);
+       device.read(&clustersPerGroup, 4);
+
+       // read bitmap
+       bitmap.resize(totalBlockCount + 1);
+
+       unsigned int groupDescCount = divCeilSafely(totalBlockCount - firstDataBlock, blocksPerGroup);
+       int blockNbytes = clustersPerGroup / 8;
+
+       // read group_desc
+       unsigned int descPerBlock = blockSize / ODE_EXT2_MIN_DESC_SIZE;
+       unsigned int descBlockCount = divCeilSafely(groupDescCount, descPerBlock);
+
+       // read first meta block
+       data group_desc(descBlockCount * blockSize);
+       device.lseek((firstDataBlock + 1) * blockSize, SEEK_SET);
+       device.read(group_desc.data(), (descBlockCount * blockSize));
+
+       unsigned int cnt = 0;
+       unsigned int blkItr = firstDataBlock;
+
+       // this structure just is used for easy type-casting.
+       struct odeExtGroupDesc {
+               unsigned int    blockBitmap;    /* Blocks bitmap block */
+               /* skip other member */
+       };
+
+       for (unsigned int i = 0; i < groupDescCount; i++) {
+               data block_bitmap(blockSize);
+
+               unsigned int blk = (((struct odeExtGroupDesc *)(((unsigned char *)(group_desc.data())) + i * ODE_EXT2_MIN_DESC_SIZE))->blockBitmap);
+               device.lseek(blk * blockSize, SEEK_SET);
+               device.read(block_bitmap.data(), blockSize);
+
+               cnt = blockNbytes << 3;
+               memcpy(bitmap.data() + (blkItr >> 3), block_bitmap.data(), (cnt + 7) >> 3);
+               blkItr += blockNbytes << 3;
+       }
+
+       device.close();
+}
+
+Ext4Tool::~Ext4Tool()
+{
+}
+
+unsigned int Ext4Tool::getTotalBlockCount()
+{
+       return totalBlockCount;
+}
+
+bool Ext4Tool::isUsedBlock(unsigned int blockIndex)
+{
+       unsigned char *addr = (bitmap.data() + (blockIndex >> 3));
+       int mask = 1 << (blockIndex & 0x07);
+
+       if (mask & *addr)
+               return true;
+
+       return false;
+}
+
+void Ext4Tool::forceCleanUp()
+{
+       std::vector<std::string> args = {
+               "-f",
+               "-y",
+               source
+       };
+
+       runtime::Process proc("/sbin/e2fsck", args);
+       proc.execute();
+       proc.waitForFinished();
+}
+
+} // namespace ode

diff --git a/server/ext4-tool.h b/server/ext4-tool.h
new file mode 100644 (file)
index 0000000..fb10912
--- /dev/null
+++ b/server/ext4-tool.h
@@ -0,0 +1,50 @@
+/*
+ *  Copyright (c) 2016 Samsung Electronics Co., Ltd All Rights Reserved
+ *
+ *  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 __EXT4_TOOL_H__
+#define __EXT4_TOOL_H__
+
+#include <string>
+#include <vector>
+
+namespace ode {
+
+class Ext4Tool final {
+public:
+       Ext4Tool(const std::string &src);
+       Ext4Tool(const Ext4Tool &) = delete;
+       Ext4Tool(Ext4Tool &&) = delete;
+       ~Ext4Tool();
+
+       Ext4Tool &operator=(const Ext4Tool &) = delete;
+       Ext4Tool &operator=(Ext4Tool &&) = delete;
+
+       typedef std::vector<unsigned char> data;
+
+       unsigned int getTotalBlockCount();
+       bool isUsedBlock(unsigned int blockIndex);
+
+       void forceCleanUp();
+
+private:
+       std::string source;
+       unsigned int totalBlockCount;
+       data bitmap;
+};
+
+} // namespace ode
+
+#endif // __EXT4_TOOL_H__