Determine if running on a rooted device

My app has a certain piece of functionality that will only work on a device where root is available. Rather than having this feature fail when it is used (and then show an appropriate error message to the user), I'd prefer an ability to silently check if root is available first, and if not,hide the respective options in the first place.

Is there a way to do this?

Here is a class that will check for Root one of three ways.

/** @author Kevin Kowalewski */
public class RootUtil {
    public static boolean isDeviceRooted() {
        return checkRootMethod1() || checkRootMethod2() || checkRootMethod3();
    }

    private static boolean checkRootMethod1() {
        String buildTags = android.os.Build.TAGS;
        return buildTags != null && buildTags.contains("test-keys");
    }

    private static boolean checkRootMethod2() {
        String[] paths = { "/system/app/Superuser.apk", "/sbin/su", "/system/bin/su", "/system/xbin/su", "/data/local/xbin/su", "/data/local/bin/su", "/system/sd/xbin/su",
                "/system/bin/failsafe/su", "/data/local/su", "/su/bin/su"};
        for (String path : paths) {
            if (new File(path).exists()) return true;
        }
        return false;
    }

    private static boolean checkRootMethod3() {
        Process process = null;
        try {
            process = Runtime.getRuntime().exec(new String[] { "/system/xbin/which", "su" });
            BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
            if (in.readLine() != null) return true;
            return false;
        } catch (Throwable t) {
            return false;
        } finally {
            if (process != null) process.destroy();
        }
    }
}

If you are already using Fabric/Firebase Crashlytics you can call

CommonUtils.isRooted(context)

This is the current implementation of that method:

public static boolean isRooted(Context context) {
    boolean isEmulator = isEmulator(context);
    String buildTags = Build.TAGS;
    if (!isEmulator && buildTags != null && buildTags.contains("test-keys")) {
        return true;
    } else {
        File file = new File("/system/app/Superuser.apk");
        if (file.exists()) {
            return true;
        } else {
            file = new File("/system/xbin/su");
            return !isEmulator && file.exists();
        }
    }
}

public static boolean isEmulator(Context context) {
    String androidId = Secure.getString(context.getContentResolver(), "android_id");
    return "sdk".equals(Build.PRODUCT) || "google_sdk".equals(Build.PRODUCT) || androidId == null;
}

The RootTools library offers simple methods to check for root:

RootTools.isRootAvailable()

Reference

In my application I was checking if device is rooted or not by executing "su" command. But today I've removed this part of my code. Why?

Because my application became a memory killer. How? Let me tell you my story.

There were some complaints that my application was slowing down devices(Of course I thought that can not be true). I tried to figure out why. So I used MAT to get heap dumps and analyze, and everything seemed perfect. But after relaunching my app many times I realized that device is really getting slower and stopping my application didn't make it faster (unless I restart device). I analyzed dump files again while device is very slow. But everything was still perfect for dump file. Then I did what must be done at first. I listed processes.

$ adb shell ps

Surprize; there were many processes for my application (with my application's process tag at manifest). Some of them was zombie some of them not.

With a sample application which has a single Activity and executes just "su" command, I realized that a zombie process is being created on every launch of application. At first these zombies allocate 0KB but than something happens and zombie processes are holding nearly same KBs as my application's main process and they became standart processes.

There is a bug report for same issue on bugs.sun.com: http://bugs.sun.com/view_bug.do?bug_id=6474073 this explains if command is not found zombies are going to be created with exec() method. But I still don't understand why and how can they become standart processes and hold significant KBs. (This is not happening all the time)

You can try if you want with code sample below;

String commandToExecute = "su";
executeShellCommand(commandToExecute);

Simple command execution method;

private boolean executeShellCommand(String command){
	Process process = null;            
	try{
		process = Runtime.getRuntime().exec(command);
		return true;
	} catch (Exception e) {
		return false;
	} finally{
		if(process != null){
			try{
				process.destroy();
			}catch (Exception e) {
			}
		}
	}
}

To sum up; I have no advice for you to determine if device is rooted or not. But if I were you I would not use Runtime.getRuntime().exec().

By the way; RootTools.isRootAvailable() causes same problem.

Many of the answers listed here have inherent issues:

• Checking for test-keys is correlated with root access but doesn't necessarily guarantee it
• "PATH" directories should be derived from the actual "PATH" environment variable instead of being hard coded
• The existence of the "su" executable doesn't necessarily mean the device has been rooted
• The "which" executable may or may not be installed, and you should let the system resolve its path if possible
• Just because the SuperUser app is installed on the device does not mean the device has root access yet

The RootTools library from Stericson seems to be checking for root more legitimately. It also has lots of extra tools and utilities so I highly recommend it. However, there's no explanation of how it specifically checks for root, and it may be a bit heavier than most apps really need.

I've made a couple of utility methods that are loosely based on the RootTools library. If you simply want to check if the "su" executable is on the device you can use the following method:

public static boolean isRootAvailable(){
    for(String pathDir : System.getenv("PATH").split(":")){
        if(new File(pathDir, "su").exists()) {
            return true;
        }
    }
    return false;
}

This method simply loops through the directories listed in the "PATH" environment variable and checks if a "su" file exists in one of them.

In order to truly check for root access the "su" command must actually be run. If an app like SuperUser is installed, then at this point it may ask for root access, or if its already been granted/denied a toast may be shown indicating whether access was granted/denied. A good command to run is "id" so that you can verify that the user id is in fact 0 (root).

Here's a sample method to determine whether root access has been granted:

public static boolean isRootGiven(){
    if (isRootAvailable()) {
        Process process = null;
        try {
            process = Runtime.getRuntime().exec(new String[]{"su", "-c", "id"});
            BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
            String output = in.readLine();
            if (output != null && output.toLowerCase().contains("uid=0"))
                return true;
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (process != null)
                process.destroy();
        }
    }

    return false;
}

It's important to actually test running the "su" command because some emulators have the "su" executable pre-installed, but only allow certain users to access it like the adb shell.

It's also important to check for the existence of the "su" executable before trying to run it, because android has been known to not properly dispose of processes that try to run missing commands. These ghost processes can run up memory consumption over time.

Update 2017

You can do it now with Google Safetynet API. The SafetyNet API provides Attestation API which helps you assess the security and compatibility of the Android environments in which your apps run.

This attestation can helps to determine whether or not the particular device has been tampered with or otherwise modified.

The Attestation API returns a JWS response like this

{
  "nonce": "R2Rra24fVm5xa2Mg",
  "timestampMs": 9860437986543,
  "apkPackageName": "com.package.name.of.requesting.app",
  "apkCertificateDigestSha256": ["base64 encoded, SHA-256 hash of the
                                  certificate used to sign requesting app"],
  "apkDigestSha256": "base64 encoded, SHA-256 hash of the app's APK",
  "ctsProfileMatch": true,
  "basicIntegrity": true,
}

Parsing this response can help you determine if device is rooted or not

> Rooted devices seem to cause ctsProfileMatch=false.

You can do it on client side but parsing response on server side is recommend. A basic client server archtecture with safety net API will look like this:-

Root check at Java level is not a safe solution. If your app has Security Concerns to run on a Rooted device , then please use this solution.

Kevin's answer works unless the phone also has an app like RootCloak . Such apps have a Handle over Java APIs once phone is rooted and they mock these APIs to return phone is not rooted.

I have written a native level code based on Kevin's answer , it works even with RootCloak ! Also it does not cause any memory leak issues.

#include <string.h>
#include <jni.h>
#include <time.h>
#include <sys/stat.h>
#include <stdio.h>
#include "android_log.h"
#include <errno.h>
#include <unistd.h>
#include <sys/system_properties.h>

JNIEXPORT int JNICALL Java_com_test_RootUtils_checkRootAccessMethod1(
		JNIEnv* env, jobject thiz) {
	
	
	//Access function checks whether a particular file can be accessed
	int result = access("/system/app/Superuser.apk",F_OK);
	
	ANDROID_LOGV( "File Access Result %d\n", result);
	
	int len;
	char build_tags[PROP_VALUE_MAX]; // PROP_VALUE_MAX from <sys/system_properties.h>.
	len = __system_property_get(ANDROID_OS_BUILD_TAGS, build_tags); // On return, len will equal (int)strlen(model_id).
	if(strcmp(build_tags,"test-keys") == 0){
		ANDROID_LOGV( "Device has test keys\n", build_tags);
		result = 0;
	}
	ANDROID_LOGV( "File Access Result %s\n", build_tags);
    return result;

}

JNIEXPORT int JNICALL Java_com_test_RootUtils_checkRootAccessMethod2(
		JNIEnv* env, jobject thiz) {
	//which command is enabled only after Busy box is installed on a rooted device
	//Outpput of which command is the path to su file. On a non rooted device , we will get a null/ empty path
	//char* cmd = const_cast<char *>"which su";
	FILE* pipe = popen("which su", "r");
    if (!pipe) return -1;
    char buffer[128];
    std::string resultCmd = "";
    while(!feof(pipe)) {
    	if(fgets(buffer, 128, pipe) != NULL)
    		resultCmd += buffer;
    }
    pclose(pipe);
	
	const char *cstr = resultCmd.c_str();
	int result = -1;
	if(cstr == NULL || (strlen(cstr) == 0)){
		ANDROID_LOGV( "Result of Which command is Null");
	}else{
		result = 0;
		ANDROID_LOGV( "Result of Which command %s\n", cstr);
		}
    return result;

}

JNIEXPORT int JNICALL Java_com_test_RootUtils_checkRootAccessMethod3(
		JNIEnv* env, jobject thiz) {

	
	int len;
	char build_tags[PROP_VALUE_MAX]; // PROP_VALUE_MAX from <sys/system_properties.h>.
	int result = -1;
	len = __system_property_get(ANDROID_OS_BUILD_TAGS, build_tags); // On return, len will equal (int)strlen(model_id).
	if(len >0 && strstr(build_tags,"test-keys") != NULL){
		ANDROID_LOGV( "Device has test keys\n", build_tags);
		result = 0;
	}
	
    return result;

}

In your Java code , you need to create wrapper class RootUtils to make the native calls

    public boolean checkRooted() {

       if( rootUtils.checkRootAccessMethod3()  == 0 || rootUtils.checkRootAccessMethod1()  == 0 || rootUtils.checkRootAccessMethod2()  == 0 )
	       return true;
      return false;
     }

http://code.google.com/p/roottools/

If you do not want to use the jar file just use the code:

public static boolean findBinary(String binaryName) {
		boolean found = false;
		if (!found) {
			String[] places = { "/sbin/", "/system/bin/", "/system/xbin/",
					"/data/local/xbin/", "/data/local/bin/",
					"/system/sd/xbin/", "/system/bin/failsafe/", "/data/local/" };
			for (String where : places) {
				if (new File(where + binaryName).exists()) {
					found = true;

					break;
				}
			}
		}
		return found;
	}

Program will try to find su folder:

private static boolean isRooted() {
		return findBinary("su");
	}

Example:

if (isRooted()) {
   textView.setText("Device Rooted");

} else {
   textView.setText("Device Unrooted");
}

RootBeer is a root checking Android library by Scott and Matthew. It uses various checks to indicate whether device is rooted or not.

> Java checks > > - CheckRootManagementApps >
>
> - CheckPotentiallyDangerousAppss > >
>
> > - CheckRootCloakingApps > >
>
> > - CheckTestKeys > >
>
> > - checkForDangerousProps > >
>
> > - checkForBusyBoxBinary > >
>
> > - checkForSuBinary > >
>
> > - checkSuExists > >
>
> > - checkForRWSystem > > Native checks > > We call through to our native root checker to run some of it's own > checks. Native checks are typically harder to cloak, so some root > cloak apps just block the loading of native libraries that contain > certain key words. > > - checkForSuBinary

Instead of using isRootAvailable() you can use isAccessGiven(). Direct from RootTools wiki:

if (RootTools.isAccessGiven()) {
    // your app has been granted root access
}

> RootTools.isAccessGiven() not only checks that a device is rooted, it > also calls su for your app, requests permission, and returns true if > your app was successfully granted root permissions. This can be used > as the first check in your app to make sure that you will be granted > access when you need it.

Reference

Some modified builds used to set the system property ro.modversion for this purpose. Things seem to have moved on; my build from TheDude a few months ago has this:

cmb@apollo:~$ adb -d shell getprop |grep build
[ro.build.id]: [CUPCAKE]
[ro.build.display.id]: [htc_dream-eng 1.5 CUPCAKE eng.TheDudeAbides.20090427.235325 test-keys]
[ro.build.version.incremental]: [eng.TheDude.2009027.235325]
[ro.build.version.sdk]: [3]
[ro.build.version.release]: [1.5]
[ro.build.date]: [Mon Apr 20 01:42:32 CDT 2009]
[ro.build.date.utc]: [1240209752]
[ro.build.type]: [eng]
[ro.build.user]: [TheDude]
[ro.build.host]: [ender]
[ro.build.tags]: [test-keys]
[ro.build.product]: [dream]
[ro.build.description]: [kila-user 1.1 PLAT-RC33 126986 ota-rel-keys,release-keys]
[ro.build.fingerprint]: [tmobile/kila/dream/trout:1.1/PLAT-RC33/126986:user/ota-rel-keys,release-keys]
[ro.build.changelist]: [17615# end build properties]

The emulator from the 1.5 SDK on the other hand, running the 1.5 image, also has root, is probably similar to the Android Dev Phone 1 (which you presumably want to allow) and has this:

cmb@apollo:~$ adb -e shell getprop |grep build
[ro.build.id]: [CUPCAKE]
[ro.build.display.id]: [sdk-eng 1.5 CUPCAKE 148875 test-keys]
[ro.build.version.incremental]: [148875]
[ro.build.version.sdk]: [3]
[ro.build.version.release]: [1.5]
[ro.build.date]: [Thu May 14 18:09:10 PDT 2009]
[ro.build.date.utc]: [1242349750]
[ro.build.type]: [eng]
[ro.build.user]: [android-build]
[ro.build.host]: [undroid16.mtv.corp.google.com]
[ro.build.tags]: [test-keys]
[ro.build.product]: [generic]
[ro.build.description]: [sdk-eng 1.5 CUPCAKE 148875 test-keys]
[ro.build.fingerprint]: [generic/sdk/generic/:1.5/CUPCAKE/148875:eng/test-keys]

As for the retail builds, I don't have one to hand, but various searches under site:xda-developers.com are informative. Here is a G1 in the Netherlands, you can see that ro.build.tags does not have test-keys, and I think that's probably the most reliable property to use.

I suggest using native code for root detection. Here is a full working example.

JAVA wrapper:

package com.kozhevin.rootchecks.util;


import android.support.annotation.NonNull;

import com.kozhevin.rootchecks.BuildConfig;

public class MeatGrinder {
    private final static String LIB_NAME = "native-lib";
    private static boolean isLoaded;
    private static boolean isUnderTest = false;

    private MeatGrinder() {

    }

    public boolean isLibraryLoaded() {
        if (isLoaded) {
            return true;
        }
        try {
            if(isUnderTest) {
                throw new UnsatisfiedLinkError("under test");
            }
            System.loadLibrary(LIB_NAME);
            isLoaded = true;
        } catch (UnsatisfiedLinkError e) {
            if (BuildConfig.DEBUG) {
                e.printStackTrace();
            }
        }
        return isLoaded;
    }

    public native boolean isDetectedDevKeys();

    public native boolean isDetectedTestKeys();

    public native boolean isNotFoundReleaseKeys();

    public native boolean isFoundDangerousProps();

    public native boolean isPermissiveSelinux();

    public native boolean isSuExists();

    public native boolean isAccessedSuperuserApk();

    public native boolean isFoundSuBinary();

    public native boolean isFoundBusyboxBinary();

    public native boolean isFoundXposed();

    public native boolean isFoundResetprop();

    public native boolean isFoundWrongPathPermission();

    public native boolean isFoundHooks();

    @NonNull
    public static MeatGrinder getInstance() {
        return InstanceHolder.INSTANCE;
    }

    private static class InstanceHolder {
        private static final MeatGrinder INSTANCE = new MeatGrinder();
    }
}

JNI wrapper(native-lib.c):

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isDetectedTestKeys(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isDetectedTestKeys();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isDetectedDevKeys(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isDetectedDevKeys();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isNotFoundReleaseKeys(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isNotFoundReleaseKeys();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundDangerousProps(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundDangerousProps();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isPermissiveSelinux(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isPermissiveSelinux();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isSuExists(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isSuExists();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isAccessedSuperuserApk(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isAccessedSuperuserApk();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundSuBinary(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundSuBinary();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundBusyboxBinary(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundBusyboxBinary();
}


JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundXposed(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundXposed();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundResetprop(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundResetprop();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundWrongPathPermission(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundWrongPathPermission();
}

JNIEXPORT jboolean JNICALL
Java_com_kozhevin_rootchecks_util_MeatGrinder_isFoundHooks(
        JNIEnv *env,
        jobject  this ) {

    return (jboolean) isFoundHooks();
}

constants:

// Comma-separated tags describing the build, like= "unsigned,debug".
const char *const ANDROID_OS_BUILD_TAGS = "ro.build.tags";

// A string that uniquely identifies this build. 'BRAND/PRODUCT/DEVICE:RELEASE/ID/VERSION.INCREMENTAL:TYPE/TAGS'.
const char *const ANDROID_OS_BUILD_FINGERPRINT = "ro.build.fingerprint";

const char *const ANDROID_OS_SECURE = "ro.secure";

const char *const ANDROID_OS_DEBUGGABLE = "ro.debuggable";
const char *const ANDROID_OS_SYS_INITD = "sys.initd";
const char *const ANDROID_OS_BUILD_SELINUX = "ro.build.selinux";
//see https://android.googlesource.com/platform/system/core/+/master/adb/services.cpp#86
const char *const SERVICE_ADB_ROOT = "service.adb.root";

const char * const MG_SU_PATH[] = {
        "/data/local/",
        "/data/local/bin/",
        "/data/local/xbin/",
        "/sbin/",
        "/system/bin/",
        "/system/bin/.ext/",
        "/system/bin/failsafe/",
        "/system/sd/xbin/",
        "/su/xbin/",
        "/su/bin/",
        "/magisk/.core/bin/",
        "/system/usr/we-need-root/",
        "/system/xbin/",
        0
};

const char * const MG_EXPOSED_FILES[] = {
        "/system/lib/libxposed_art.so",
        "/system/lib64/libxposed_art.so",
        "/system/xposed.prop",
        "/cache/recovery/xposed.zip",
        "/system/framework/XposedBridge.jar",
        "/system/bin/app_process64_xposed",
        "/system/bin/app_process32_xposed",
        "/magisk/xposed/system/lib/libsigchain.so",
        "/magisk/xposed/system/lib/libart.so",
        "/magisk/xposed/system/lib/libart-disassembler.so",
        "/magisk/xposed/system/lib/libart-compiler.so",
        "/system/bin/app_process32_orig",
        "/system/bin/app_process64_orig",
        0
};

const char * const MG_READ_ONLY_PATH[] = {
        "/system",
        "/system/bin",
        "/system/sbin",
        "/system/xbin",
        "/vendor/bin",
        "/sbin",
        "/etc",
        0
};

root detections from native code:

struct mntent *getMntent(FILE *fp, struct mntent *e, char *buf, int buf_len) {

    while (fgets(buf, buf_len, fp) != NULL) {
        // Entries look like "/dev/block/vda /system ext4 ro,seclabel,relatime,data=ordered 0 0".
        // That is: mnt_fsname mnt_dir mnt_type mnt_opts mnt_freq mnt_passno.
        int fsname0, fsname1, dir0, dir1, type0, type1, opts0, opts1;
        if (sscanf(buf, " %n%*s%n %n%*s%n %n%*s%n %n%*s%n %d %d",
                   &fsname0, &fsname1, &dir0, &dir1, &type0, &type1, &opts0, &opts1,
                   &e->mnt_freq, &e->mnt_passno) == 2) {
            e->mnt_fsname = &buf[fsname0];
            buf[fsname1] = '\0';
            e->mnt_dir = &buf[dir0];
            buf[dir1] = '\0';
            e->mnt_type = &buf[type0];
            buf[type1] = '\0';
            e->mnt_opts = &buf[opts0];
            buf[opts1] = '\0';
            return e;
        }
    }
    return NULL;
}


bool isPresentMntOpt(const struct mntent *pMnt, const char *pOpt) {
    char *token = pMnt->mnt_opts;
    const char *end = pMnt->mnt_opts + strlen(pMnt->mnt_opts);
    const size_t optLen = strlen(pOpt);
    while (token != NULL) {
        const char *tokenEnd = token + optLen;
        if (tokenEnd > end) break;
        if (memcmp(token, pOpt, optLen) == 0 &&
            (*tokenEnd == '\0' || *tokenEnd == ',' || *tokenEnd == '=')) {
            return true;
        }
        token = strchr(token, ',');
        if (token != NULL) {
            token++;
        }
    }
    return false;
}

static char *concat2str(const char *pString1, const char *pString2) {
    char *result;
    size_t lengthBuffer = 0;

    lengthBuffer = strlen(pString1) +
                   strlen(pString2) + 1;
    result = malloc(lengthBuffer);
    if (result == NULL) {
        GR_LOGW("malloc failed\n");
        return NULL;
    }
    memset(result, 0, lengthBuffer);
    strcpy(result, pString1);
    strcat(result, pString2);
    return result;
}

static bool
isBadPropertyState(const char *key, const char *badValue, bool isObligatoryProperty, bool isExact) {
    if (badValue == NULL) {
        GR_LOGE("badValue may not be NULL");
        return false;
    }
    if (key == NULL) {
        GR_LOGE("key may not be NULL");
        return false;
    }
    char value[PROP_VALUE_MAX + 1];
    int length = __system_property_get(key, value);
    bool result = false;
    /* A length 0 value indicates that the property is not defined */
    if (length > 0) {
        GR_LOGI("property:[%s]==[%s]", key, value);
        if (isExact) {
            if (strcmp(value, badValue) == 0) {
                GR_LOGW("bad value[%s] equals to [%s] in the property [%s]", value, badValue, key);
                result = true;
            }
        } else {
            if (strlen(value) >= strlen(badValue) && strstr(value, badValue) != NULL) {
                GR_LOGW("bad value[%s] found in [%s] in the property [%s]", value, badValue, key);
                result = true;
            }
        }
    } else {
        GR_LOGI("[%s] property not found", key);
        if (isObligatoryProperty) {
            result = true;
        }
    }
    return result;
}

bool isDetectedTestKeys() {
    const char *TEST_KEYS_VALUE = "test-keys";
    return isBadPropertyState(ANDROID_OS_BUILD_TAGS, TEST_KEYS_VALUE, true, false);
}

bool isDetectedDevKeys() {
    const char *DEV_KEYS_VALUE = "dev-keys";
    return isBadPropertyState(ANDROID_OS_BUILD_TAGS, DEV_KEYS_VALUE, true, false);
}

bool isNotFoundReleaseKeys() {
    const char *RELEASE_KEYS_VALUE = "release-keys";
    return !isBadPropertyState(ANDROID_OS_BUILD_TAGS, RELEASE_KEYS_VALUE, false, true);
}

bool isFoundWrongPathPermission() {

    bool result = false;
    FILE *file = fopen("/proc/mounts", "r");
    char mntent_strings[BUFSIZ];
    if (file == NULL) {
        GR_LOGE("setmntent");
        return result;
    }

    struct mntent ent = {0};
    while (NULL != getMntent(file, &ent, mntent_strings, sizeof(mntent_strings))) {
        for (size_t i = 0; MG_READ_ONLY_PATH[i]; i++) {
            if (strcmp((&ent)->mnt_dir, MG_READ_ONLY_PATH[i]) == 0 &&
                isPresentMntOpt(&ent, "rw")) {
                GR_LOGI("%s %s %s %s\n", (&ent)->mnt_fsname, (&ent)->mnt_dir, (&ent)->mnt_opts,
                        (&ent)->mnt_type);
                result = true;
                break;
            }
        }
        memset(&ent, 0, sizeof(ent));
    }
    fclose(file);
    return result;
}


bool isFoundDangerousProps() {
    const char *BAD_DEBUGGABLE_VALUE = "1";
    const char *BAD_SECURE_VALUE = "0";
    const char *BAD_SYS_INITD_VALUE = "1";
    const char *BAD_SERVICE_ADB_ROOT_VALUE = "1";

    bool result = isBadPropertyState(ANDROID_OS_DEBUGGABLE, BAD_DEBUGGABLE_VALUE, true, true) ||
                  isBadPropertyState(SERVICE_ADB_ROOT, BAD_SERVICE_ADB_ROOT_VALUE, false, true) ||
                  isBadPropertyState(ANDROID_OS_SECURE, BAD_SECURE_VALUE, true, true) ||
                  isBadPropertyState(ANDROID_OS_SYS_INITD, BAD_SYS_INITD_VALUE, false, true);

    return result;
}

bool isPermissiveSelinux() {
    const char *BAD_VALUE = "0";
    return isBadPropertyState(ANDROID_OS_BUILD_SELINUX, BAD_VALUE, false, false);
}

bool isSuExists() {
    char buf[BUFSIZ];
    char *str = NULL;
    char *temp = NULL;
    size_t size = 1;  // start with size of 1 to make room for null terminator
    size_t strlength;

    FILE *pipe = popen("which su", "r");
    if (pipe == NULL) {
        GR_LOGI("pipe is null");
        return false;
    }

    while (fgets(buf, sizeof(buf), pipe) != NULL) {
        strlength = strlen(buf);
        temp = realloc(str, size + strlength);  // allocate room for the buf that gets appended
        if (temp == NULL) {
            // allocation error
            GR_LOGE("Error (re)allocating memory");
            pclose(pipe);
            if (str != NULL) {
                free(str);
            }
            return false;
        } else {
            str = temp;
        }
        strcpy(str + size - 1, buf);
        size += strlength;
    }
    pclose(pipe);
    GR_LOGW("A size of the result from pipe is [%zu], result:\n [%s] ", size, str);
    if (str != NULL) {
        free(str);
    }
    return size > 1 ? true : false;
}

static bool isAccessedFile(const char *path) {
    int result = access(path, F_OK);
    GR_LOGV("[%s] has been accessed with result: [%d]", path, result);
    return result == 0 ? true : false;
}

static bool isFoundBinaryFromArray(const char *const *array, const char *binary) {
    for (size_t i = 0; array[i]; ++i) {
        char *checkedPath = concat2str(array[i], binary);
        if (checkedPath == NULL) { // malloc failed
            return false;
        }
        bool result = isAccessedFile(checkedPath);
        free(checkedPath);
        if (result) {
            return result;
        }
    }
    return false;
}

bool isAccessedSuperuserApk() {
    return isAccessedFile("/system/app/Superuser.apk");
}

bool isFoundResetprop() {
    return isAccessedFile("/data/magisk/resetprop");
}

bool isFoundSuBinary() {
    return isFoundBinaryFromArray(MG_SU_PATH, "su");
}

bool isFoundBusyboxBinary() {
    return isFoundBinaryFromArray(MG_SU_PATH, "busybox");
}

bool isFoundXposed() {
    for (size_t i = 0; MG_EXPOSED_FILES[i]; ++i) {
        bool result = isAccessedFile(MG_EXPOSED_FILES[i]);
        if (result) {
            return result;
        }
    }
    return false;
}

bool isFoundHooks() {
    bool result = false;
    pid_t pid = getpid();
    char maps_file_name[512];
    sprintf(maps_file_name, "/proc/%d/maps", pid);
    GR_LOGI("try to open [%s]", maps_file_name);
    const size_t line_size = BUFSIZ;
    char *line = malloc(line_size);
    if (line == NULL) {
        return result;
    }
    FILE *fp = fopen(maps_file_name, "r");
    if (fp == NULL) {
        free(line);
        return result;
    }
    memset(line, 0, line_size);
    const char *substrate = "com.saurik.substrate";
    const char *xposed = "XposedBridge.jar";
    while (fgets(line, line_size, fp) != NULL) {
        const size_t real_line_size = strlen(line);
        if ((real_line_size >= strlen(substrate) && strstr(line, substrate) != NULL) ||
            (real_line_size >= strlen(xposed) && strstr(line, xposed) != NULL)) {
            GR_LOGI("found in [%s]: [%s]", maps_file_name, line);
            result = true;
            break;
        }
    }
    free(line);
    fclose(fp);
    return result;
}

Here is my code based on some answers here:

 /**
   * Checks if the phone is rooted.
   * 
   * @return <code>true</code> if the phone is rooted, <code>false</code>
   * otherwise.
   */
  public static boolean isPhoneRooted() {

    // get from build info
    String buildTags = android.os.Build.TAGS;
    if (buildTags != null && buildTags.contains("test-keys")) {
      return true;
    }

    // check if /system/app/Superuser.apk is present
    try {
      File file = new File("/system/app/Superuser.apk");
      if (file.exists()) {
        return true;
      }
    } catch (Throwable e1) {
      // ignore
    }

    return false;
  }

Further to @Kevins answer, I've recently found while using his system, that the Nexus 7.1 was returning false for all three methods - No which command, no test-keys and SuperSU was not installed in /system/app.

I added this:

public static boolean checkRootMethod4(Context context) {
	return isPackageInstalled("eu.chainfire.supersu", context);		
}

private static boolean isPackageInstalled(String packagename, Context context) {
    PackageManager pm = context.getPackageManager();
    try {
        pm.getPackageInfo(packagename, PackageManager.GET_ACTIVITIES);
        return true;
    } catch (NameNotFoundException e) {
        return false;
    }
}

This is slightly less useful in some situations (if you need guaranteed root access) as it's completely possible for SuperSU to be installed on devices which don't have SU access.

However, since it's possible to have SuperSU installed and working but not in the /system/app directory, this extra case will root (haha) out such cases.

    public static boolean isRootAvailable(){
            Process p = null;
            try{
               p = Runtime.getRuntime().exec(new String[] {"su"});
               writeCommandToConsole(p,"exit 0");
               int result = p.waitFor();
               if(result != 0)
                   throw new Exception("Root check result with exit command " + result);
               return true;
            } catch (IOException e) {
                Log.e(LOG_TAG, "Su executable is not available ", e);
            } catch (Exception e) {
                Log.e(LOG_TAG, "Root is unavailable ", e);
            }finally {
                if(p != null)
                    p.destroy();
            }
            return false;
        }
 private static String writeCommandToConsole(Process proc, String command, boolean ignoreError) throws Exception{
            byte[] tmpArray = new byte[1024];
            proc.getOutputStream().write((command + "\n").getBytes());
            proc.getOutputStream().flush();
            int bytesRead = 0;
            if(proc.getErrorStream().available() > 0){
                if((bytesRead = proc.getErrorStream().read(tmpArray)) > 1){
                    Log.e(LOG_TAG,new String(tmpArray,0,bytesRead));
                    if(!ignoreError)
                        throw new Exception(new String(tmpArray,0,bytesRead));
                }
            }
            if(proc.getInputStream().available() > 0){
                bytesRead = proc.getInputStream().read(tmpArray);
                Log.i(LOG_TAG, new String(tmpArray,0,bytesRead));
            }
            return new String(tmpArray);
        }

Two additional ideas, if you want to check if a device is root capable from your app:

1. Check for the existing of the 'su' binary: run "which su" from Runtime.getRuntime().exec()
2. Look for the SuperUser.apk in /system/app/Superuser.apk location

Using C++ with the ndk is the best approach to detect root even if the user is using applications that hide his root such as RootCloak. I tested this code with RootCloak and I was able to detect the root even if the user is trying to hide it. So your cpp file would like:

#include <jni.h>
#include <string>


/**
 *
 * function that checks for the su binary files and operates even if 
 * root cloak is installed
 * @return integer 1: device is rooted, 0: device is not 
 *rooted
*/
extern "C"
JNIEXPORT int JNICALL


Java_com_example_user_root_1native_rootFunction(JNIEnv *env,jobject thiz){
const char *paths[] ={"/system/app/Superuser.apk", "/sbin/su", "/system/bin/su",
                      "/system/xbin/su", "/data/local/xbin/su", "/data/local/bin/su", "/system/sd/xbin/su",
                      "/system/bin/failsafe/su", "/data/local/su", "/su/bin/su"};

int counter =0;
while (counter<9){
    if(FILE *file = fopen(paths[counter],"r")){
        fclose(file);
        return 1;
    }
    counter++;
}
return 0;
}

And you will call the function from your java code as follows

public class Root_detect {
    
    

   /**
    *
    * function that calls a native function to check if the device is 
    *rooted or not
    * @return boolean: true if the device is rooted, false if the 
    *device is not rooted
   */
   public boolean check_rooted(){

        int checker = rootFunction();
        
        if(checker==1){
           return true;
        }else {
           return false;
        }
   }
   static {
    System.loadLibrary("cpp-root-lib");//name of your cpp file
   }

   public native int rootFunction();
}

if [[ "`adb shell which su | grep -io "permission denied"`" != "permission denied" ]]; then
   echo "Yes. Rooted device."
 else
   echo "No. Device not rooted. Only limited tasks can be performed. Done."
    zenity --warning --title="Device Not Rooted" --text="The connected Android Device is <b>NOT ROOTED</b>. Only limited tasks can be performed." --no-wrap
fi

Forget all that detecting root apps and su binaries. Check for the root daemon process. This can be done from the terminal and you can run terminal commands within an app. Try this one-liner.

if [ ! "$(/system/bin/ps -A | grep -v grep | grep -c daemonsu)" = "0" ]; then echo "device is rooted"; else echo "device is not rooted"; fi

You don't need root permission to achieve this either.

Edit: Now using this method for better detection!

if [ $(ps -A | grep -e ^shell -e ^root | grep -v "\[" | tr -s ' ' | cut -d ' ' -f 9 | grep -c su) ] || [ $(which su) ]; then echo 'rooted'; else echo 'not rooted'; fi

Based on some of the answers here, I merged them and also added a check if some known root-manager app is installed:

fun isProbablyRooted(context: Context, alsoIncludeCheckingRootManagerApp: Boolean = false): Boolean {
    return hasRootManagerSystemApp(context) || (alsoIncludeCheckingRootManagerApp && hasRootManagerSystemApp(context))
}

fun hasRootManagerSystemApp(context: Context): Boolean {
    val rootAppsPackageNames = arrayOf("com.topjohnwu.magisk", "eu.chainfire.supersu", "com.koushikdutta.superuser", "com.noshufou.android.su", "me.phh.superuser")
    rootAppsPackageNames.forEach { rootAppPackageName ->
        try {
            context.packageManager.getApplicationInfo(rootAppPackageName, 0)
            return true
        } catch (e: Exception) {
        }
    }
    return false
}

fun hasSuBinary(): Boolean {
    return try {
        findBinary("su")
    } catch (e: Exception) {
        e.printStackTrace()
        false
    }
}

private fun findBinary(binaryName: String): Boolean {
    val paths = System.getenv("PATH")
    if (!paths.isNullOrBlank()) {
        val systemPlaces: List<String> = paths.split(":")
        return systemPlaces.firstOrNull { File(it, binaryName).exists() } != null
    }
    val places = arrayOf("/sbin/", "/system/bin/", "/system/xbin/", "/data/local/xbin/", "/data/local/bin/",
            "/system/sd/xbin/", "/system/bin/failsafe/", "/data/local/")
    return places.firstOrNull { File(it, binaryName).exists() } != null
}

manifest:

<queries>
    <package android:name="com.topjohnwu.magisk" />
    <package android:name="eu.chainfire.supersu" />
    <package android:name="com.koushikdutta.superuser" />
    <package android:name="com.noshufou.android.su" />
    <package android:name="me.phh.superuser" />
</queries>

Of course, this is still a guess, like all the other solutions. Users can install Magisk without having the device rooted, for example.

Using google SafetyNet Attestation API you can easily check whether your device is rooted or not :

1. Add dependency in build.gradle(:app)

   implementation 'com.google.android.gms:play-services-safetynet:17.0.0'

2. Get Api key and enable Android Device Verification API using link

3. public static void sendSafetyNetRequest(Activity context) {

    if(GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(context, 13000000) == ConnectionResult.SUCCESS) {
        Log.e(TAG, "The SafetyNet Attestation API is available");
     
        // TODO(developer): Change the nonce generation to include your own, used once value,
        // ideally from your remote server.
        
        String nonceData = "Safety Net Sample: " + System.currentTimeMillis();
        ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
        Random mRandom = new SecureRandom();
   
        byte[] bytes = new byte[24];
        mRandom.nextBytes(bytes);
        try {
            byteStream.write(bytes);
            byteStream.write(nonceData.getBytes());
        } catch (IOException e) {
            e.printStackTrace();
        }
   
        byte[] nonce = byteStream.toByteArray();
        
        SafetyNetClient client = SafetyNet.getClient(context);
        Task<SafetyNetApi.AttestationResponse> task = client.attest(nonce, API_KEY_FROM_STEP_2_LINK);
   
        task.addOnSuccessListener(context, attestationResponse -> {
            
   
          /*
                 TODO(developer): Forward this result to your server together with
                 the nonce for verification.
                 You can also parse the JwsResult locally to confirm that the API
                 returned a response by checking for an 'error' field first and before
                 retrying the request with an exponential backoff.
                 NOTE: Do NOT rely on a local, client-side only check for security, you
                 must verify the response on a remote server!
                */
   
            String jwsResult = attestationResponse.getJwsResult();
   
            Log.e(TAG, "Success! SafetyNet result:\n" + jwsResult + "\n");
   
            if (jwsResult == null) {
                Log.e(TAG, "jwsResult Null");
   
            }
            final String[] jwtParts = jwsResult.split("\\.");
   
            if (jwtParts.length == 3) {
                String decodedPayload = new String(Base64.decode(jwtParts[1], Base64.DEFAULT));
                Log.e(TAG, "decodedPayload :     " + decodedPayload);
            }
   
   
        });
   
        task.addOnFailureListener(context, e -> {
            // An error occurred while communicating with the service.
            String mResult = null;
   
            if (e instanceof ApiException) {
                // An error with the Google Play Services API contains some additional details.
                ApiException apiException = (ApiException) e;
   
                Util.showLog(TAG, "Error: " +
                        CommonStatusCodes.getStatusCodeString(apiException.getStatusCode()) + ": " +
                        apiException.getStatusMessage());
            } else {
                // A different, unknown type of error occurred.
               Log.e(TAG, "ERROR! " + e.getMessage());
            }
   
        });
   
    } else {
     Log.e(TAG, "Prompt user to update Google Play services.";
        
    }
   

   } `

4. Check your logs for decodedPayload if ctsProfileMatch and basicIntegrity both are false it means your device is rooted . The Attestation API returns a JWS response which looks like:

{ "nonce": "6pLrr9zWyl6TNzj+kpbR4LZcfPY3U2FmZXR5IE5ldCBTYW1wbGU6IDE2MTQ2NzkwMTIzNjc=", "timestampMs": 9860437986543, "apkPackageName": " your package name will be displayed here", "ctsProfileMatch": true, "apkDigestSha256": [ "base64 encoded, SHA-256 hash of the certificate used to sign requesting app" ], "basicIntegrity": true, "evaluationType": "BASIC" }

For more info check this link.

As last quarter of 2021 today, I tried to use SafetyNet regarding @HimanshiThakur 's answer. But I got an issue and opened a question in here. Still no answer.

So I decided to use RootBeer. It works perfectly but when Magisk hides the root, it doesn't work.

If you don't care this case (and many bank apps can't solve this issue too), you can use these steps:

1. Add this to Gradle:

implementation 'com.scottyab:rootbeer-lib:0.1.0'

2. Use these lines:

RootBeer rootBeer = new RootBeer(context);
if (rootBeer.isRooted()) {
    //we found indication of root
} else {
    //we didn't find indication of root
}

There is Safety Net Attestation API of Google play services by which we can assess the device and determine if it is rooted/tampered.

Please go through my answer to deal with rooted devices:
https://stackoverflow.com/a/58304556/3908895

You can do this by following code :

public boolean getRootInfo() {
    if (checkRootFiles() || checkTags()) {
        return true;
    }
    return false;
}

private boolean checkRootFiles() {
    boolean root = false;
    String[] paths = {"/system/app/Superuser.apk", "/sbin/su", "/system/bin/su", "/system/xbin/su", "/data/local/xbin/su", "/data/local/bin/su", "/system/sd/xbin/su",
            "/system/bin/failsafe/su", "/data/local/su", "/su/bin/su"};
    for (String path : paths) {
        root = new File(path).exists();
        if (root)
            break;
    }
    return root;
}

private boolean checkTags() {
    String tag = Build.TAGS;
    return tag != null && tag.trim().contains("test-keys");
}

You can also check this library RootBeer.

if you don't want to use any 3rd party library or any random solution then just use google lib for detecting it.

Android Device Verification

response :

{
  "timestampMs": 9860437986543,
  "nonce": "R2Rra24fVm5xa2Mg",
  "apkPackageName": "com.package.name.of.requesting.app",
  "apkCertificateDigestSha256": ["base64 encoded, SHA-256 hash of the
                                  certificate used to sign requesting app"],
  "ctsProfileMatch": true,
  "basicIntegrity": true,
}

ctsProfileMatch it gives false if the device is rooted.

ref link: [1]: https://developer.android.com/training/safetynet/attestation

As of 2021 (today), looks like there's no any reliable way or method for detecting root, especially when powerful hiding tool such as MagiskHide is enabled. Most of the answers here are no longer relevant, so don't use it in production. Rely on proven check like SafetyNet, and instead of going the extra miles to detect root, I suggest to protect your app at both runtime, such as prevent debugger/instrumentation and make sure to use obfuscation.

Indeed it is interesting question and so far nobody has deserved award. I use the following code:

  boolean isRooted() {
      try {
				ServerSocket ss = new ServerSocket(81);
				ss.close();
                                    return true;
			} catch (Exception e) {
				// not sure
			}
    return false;
  }

The code is certainly not bulletproof, because network can be not available so you get an exception. If this method returns true then 99% you can be sure, otherwise just 50% that not. Networking permission can also spoil the solution.

Using my library at [rootbox](http://www.github.com/vaibhavpandeyvpz/rootbox "Go to github project"), it is pretty easy. Check the required code below:

    //Pass true to <Shell>.start(...) call to run as superuser
    Shell shell = null;
    try {
            shell = Shell.start(true);
    } catch (IOException exception) {
            exception.printStackTrace();
    }
    if (shell == null)
            // We failed to execute su binary
            return;
    if (shell.isRoot()) {
            // Verified running as uid 0 (root), can continue with commands
            ...
    } else
            throw Exception("Unable to gain root access. Make sure you pressed Allow/Grant in superuser prompt.");