From: s414kim <s414.kim@samsung.com>
Date: Wed, 20 Sep 2017 08:58:54 +0000 (+0900)
Subject: Remove unnecessary code of secure-erase
X-Git-Tag: submit/tizen_4.0/20171018.042033~14
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7c30174ce6acfc5fd4bee77dc2002fdde2fa2470;p=platform%2Fcore%2Fsecurity%2Fode.git

Remove unnecessary code of secure-erase

- remove reading /dev/zero code.
- changed mtab parsing code to use getmntent().

Change-Id: Ieee126dae6e33577ad9bdbb645c948db088eef3e
Signed-off-by: s414kim <s414.kim@samsung.com>
---

diff --git a/server/engine/erase/erase-engine.cpp b/server/engine/erase/erase-engine.cpp
index a6824b5..ca508de 100644
--- a/server/engine/erase/erase-engine.cpp
+++ b/server/engine/erase/erase-engine.cpp
@@ -31,20 +31,15 @@ EraseEngine::~EraseEngine()
 
 void EraseEngine::discardBlock(unsigned long long offset, blksize_t size)
 {
-	char zeros[ERASE_SIZE] = "";
+	char zero[ERASE_SIZE] = {};
 	if (size > ERASE_SIZE) {
 		throw runtime::Exception("[eraseBlock] : size is too big");
 	}
 
-	runtime::File zero("/dev/zero");
-	zero.open(O_RDONLY);
-	zero.read(zeros, sizeof(zeros));
-	zero.close();
-
 	runtime::File device(target);
 	device.open(O_WRONLY);
 	device.lseek(offset, SEEK_SET);
-	device.write(zeros, size);
+	device.write(zero, size);
 	device.close();
 }
 
diff --git a/server/secure-erase.cpp b/server/secure-erase.cpp
index a0c6cda..da67643 100644
--- a/server/secure-erase.cpp
+++ b/server/secure-erase.cpp
@@ -17,12 +17,11 @@
 #include <fstream>
 #include <vconf.h>
 #include <unistd.h>
+#include <mntent.h>
 
 #include "ext4-tool.h"
 #include "engine/erase/erase-engine.h"
-#include "engine/erase/mmc-engine.h"
 #include "rmi/secure-erase.h"
-
 #define ERASE_ENGINE EraseEngine
 #define PRIVILEGE_PLATFORM "http://tizen.org/privilege/internal/default/platform"
 
@@ -33,61 +32,21 @@ namespace {
 typedef std::unordered_map<std::string, std::string> DeviceList;
 std::unique_ptr<ERASE_ENGINE> engine;
 
-const std::string evaluateTarget(const std::string &path)
+std::string findDevPath(const std::string &mntPath)
 {
-	DeviceList deviceList;
-	DeviceList::const_iterator deviceListIter;
-	std::string subStr(path);
-	subStr.append("//");
-	std::size_t pos = 0;
-	std::string mountInfo;
-	std::string name;
-	std::string source;
-	std::string type;
-
-	runtime::File resource(path);
-	if (!resource.exists()) {
-		throw runtime::Exception("target doesn't exist");
-	}
-
-	std::ifstream file("/etc/mtab");
-	if (file.fail()) {
-		throw runtime::Exception("failed to access /etc/mtab");
-	}
-
-	while (std::getline(file, mountInfo)) {
-		pos = mountInfo.find(" ");
-		name = mountInfo.substr(0, pos);
-		mountInfo.erase(0, pos+1);
-
-		pos = mountInfo.find(" ");
-		source = mountInfo.substr(0, pos);
-		mountInfo.erase(0, pos+1);
-
-		pos = mountInfo.find(" ");
-		type = mountInfo.substr(0, pos);
-		if (!type.compare("ext2") && !type.compare("ext3")
-			&& !type.compare("ext4")) {
-			continue;
-		}
-		runtime::File device(name);
-		if (!device.exists()) {
+	std::string ret;
+	FILE* mtab = ::setmntent("/etc/mtab", "r");
+	struct ::mntent* entry = NULL;
+	while ((entry = ::getmntent(mtab)) != NULL) {
+		if (strcmp(entry->mnt_type, "ext2") && strcmp(entry->mnt_type, "ext3") && strcmp(entry->mnt_type, "ext4"))
 			continue;
-		}
-		if (device.isDevice()) {
-			deviceList.insert(std::make_pair(source, name));
-		}
-	}
-
-	pos = subStr.size();
-	while ((pos = subStr.rfind('/', pos - 1)) != std::string::npos && pos != 0) {
-		std::string subPath = subStr.substr(0, pos);
-		deviceListIter = deviceList.find(subPath);
-		if (deviceListIter != deviceList.end()) {
-			return deviceListIter->second;
+		if (mntPath == entry->mnt_dir) {
+			ret = entry->mnt_fsname;
+			break;
 		}
 	}
-	return "";
+	::endmntent(mtab);
+	return ret;
 }
 } /* namespace */
 
@@ -110,8 +69,7 @@ int SecureErase::clean(const std::string &name)
 {
 	auto cleanWorker = [name, this]() {
 		try {
-			std::string target;
-			target = evaluateTarget(name);
+			std::string target = findDevPath(name);
 			engine->cleanDevice(target);
 		} catch (runtime::Exception &e) {}
 	};