Add JNI bindings for some of the libselinux interfaces. (c07fca38) · Commits · e / os / android_frameworks_base

core/java/android/os/SELinux.java

0 → 100644

+105 −0

Original line number	Diff line number	Diff line
		package android.os;

		import java.io.FileDescriptor;

		/**
		* This class provides access to the centralized jni bindings for
		* SELinux interaction.
		* {@hide}
		*/
		public class SELinux {

		/**
		* Determine whether SELinux is disabled or enabled.
		* @return a boolean indicating whether SELinux is enabled.
		*/
		public static final native boolean isSELinuxEnabled();

		/**
		* Determine whether SELinux is permissive or enforcing.
		* @return a boolean indicating whether SELinux is enforcing.
		*/
		public static final native boolean isSELinuxEnforced();

		/**
		* Set whether SELinux is permissive or enforcing.
		* @param boolean representing whether to set SELinux to enforcing
		* @return a boolean representing whether the desired mode was set
		*/
		public static final native boolean setSELinuxEnforce(boolean value);

		/**
		* Sets the security context for newly created file objects.
		* @param context a security context given as a String.
		* @return a boolean indicating whether the operation succeeded.
		*/
		public static final native boolean setFSCreateContext(String context);

		/**
		* Change the security context of an existing file object.
		* @param path representing the path of file object to relabel.
		* @param con new security context given as a String.
		* @return a boolean indicating whether the operation succeeded.
		*/
		public static final native boolean setFileContext(String path, String context);

		/**
		* Get the security context of a file object.
		* @param path the pathname of the file object.
		* @return a security context given as a String.
		*/
		public static final native String getFileContext(String path);

		/**
		* Get the security context of a peer socket.
		* @param fd FileDescriptor class of the peer socket.
		* @return a String representing the peer socket security context.
		*/
		public static final native String getPeerContext(FileDescriptor fd);

		/**
		* Gets the security context of the current process.
		* @return a String representing the security context of the current process.
		*/
		public static final native String getContext();

		/**
		* Gets the security context of a given process id.
		* Use of this function is discouraged for Binder transactions.
		* Use Binder.getCallingSecctx() instead.
		* @param pid an int representing the process id to check.
		* @return a String representing the security context of the given pid.
		*/
		public static final native String getPidContext(int pid);

		/**
		* Gets a list of the SELinux boolean names.
		* @return an array of strings containing the SELinux boolean names.
		*/
		public static final native String[] getBooleanNames();

		/**
		* Gets the value for the given SELinux boolean name.
		* @param String The name of the SELinux boolean.
		* @return a boolean indicating whether the SELinux boolean is set.
		*/
		public static final native boolean getBooleanValue(String name);

		/**
		* Sets the value for the given SELinux boolean name.
		* @param String The name of the SELinux boolean.
		* @param Boolean The new value of the SELinux boolean.
		* @return a boolean indicating whether or not the operation succeeded.
		*/
		public static final native boolean setBooleanValue(String name, boolean value);

		/**
		* Check permissions between two security contexts.
		* @param scon The source or subject security context.
		* @param tcon The target or object security context.
		* @param tclass The object security class name.
		* @param perm The permission name.
		* @return a boolean indicating whether permission was granted.
		*/
		public static final native boolean checkSELinuxAccess(String scon, String tcon, String tclass, String perm);
		}

core/jni/Android.mk

+8 −1

Original line number	Diff line number	Diff line
		@@ -66,6 +66,7 @@ LOCAL_SRC_FILES:= \
		android_os_MessageQueue.cpp \
		android_os_ParcelFileDescriptor.cpp \
		android_os_Power.cpp \
		android_os_SELinux.cpp \
		android_os_StatFs.cpp \
		android_os_SystemClock.cpp \
		android_os_SystemProperties.cpp \
		@@ -216,7 +217,13 @@ LOCAL_SHARED_LIBRARIES := \
		libnfc_ndef \
		libusbhost \
		libharfbuzz \
		libz \
		libz

		ifeq ($(HAVE_SELINUX),true)
		LOCAL_C_INCLUDES += external/libselinux/include
		LOCAL_SHARED_LIBRARIES += libselinux
		LOCAL_CFLAGS += -DHAVE_SELINUX
		endif # HAVE_SELINUX

		ifeq ($(USE_OPENGL_RENDERER),true)
		LOCAL_SHARED_LIBRARIES += libhwui

core/jni/AndroidRuntime.cpp

+2 −0

Original line number	Diff line number	Diff line
		@@ -135,6 +135,7 @@ extern int register_android_os_Debug(JNIEnv* env);
		extern int register_android_os_MessageQueue(JNIEnv* env);
		extern int register_android_os_ParcelFileDescriptor(JNIEnv *env);
		extern int register_android_os_Power(JNIEnv *env);
		extern int register_android_os_SELinux(JNIEnv* env);
		extern int register_android_os_StatFs(JNIEnv *env);
		extern int register_android_os_SystemProperties(JNIEnv *env);
		extern int register_android_os_SystemClock(JNIEnv* env);
		@@ -1153,6 +1154,7 @@ static const RegJNIRec gRegJNI[] = {
		REG_JNI(register_android_os_MessageQueue),
		REG_JNI(register_android_os_ParcelFileDescriptor),
		REG_JNI(register_android_os_Power),
		REG_JNI(register_android_os_SELinux),
		REG_JNI(register_android_os_StatFs),
		REG_JNI(register_android_os_UEventObserver),
		REG_JNI(register_android_net_LocalSocketImpl),

core/jni/android_os_SELinux.cpp

0 → 100644

+502 −0

Original line number	Diff line number	Diff line
		#define LOG_TAG "SELinuxJNI"
		#include <utils/Log.h>

		#include "JNIHelp.h"
		#include "jni.h"
		#include "android_runtime/AndroidRuntime.h"
		#ifdef HAVE_SELINUX
		#include "selinux/selinux.h"
		#endif
		#include <errno.h>

		namespace android {

		static jboolean isSELinuxDisabled = true;

		static void throw_NullPointerException(JNIEnv env, const char msg) {
		jclass clazz;
		clazz = env->FindClass("java/lang/NullPointerException");
		env->ThrowNew(clazz, msg);
		}

		/*
		* Function: isSELinuxEnabled
		* Purpose: checks whether SELinux is enabled/disbaled
		* Parameters: none
		* Return value : true (enabled) or false (disabled)
		* Exceptions: none
		*/
		static jboolean isSELinuxEnabled(JNIEnv *env, jobject classz) {

		return !isSELinuxDisabled;
		}

		/*
		* Function: isSELinuxEnforced
		* Purpose: return the current SELinux enforce mode
		* Parameters: none
		* Return value: true (enforcing) or false (permissive)
		* Exceptions: none
		*/
		static jboolean isSELinuxEnforced(JNIEnv *env, jobject clazz) {
		#ifdef HAVE_SELINUX
		return (security_getenforce() == 1) ? true : false;
		#else
		return false;
		#endif
		}

		/*
		* Function: setSELinuxEnforce
		* Purpose: set the SE Linux enforcing mode
		* Parameters: true (enforcing) or false (permissive)
		* Return value: true (success) or false (fail)
		* Exceptions: none
		*/
		static jboolean setSELinuxEnforce(JNIEnv *env, jobject clazz, jboolean value) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return false;

		int enforce = (value) ? 1 : 0;

		return (security_setenforce(enforce) != -1) ? true : false;
		#else
		return false;
		#endif
		}

		/*
		* Function: getPeerCon
		* Purpose: retrieves security context of peer socket
		* Parameters:
		* fileDescriptor: peer socket file as a FileDescriptor object
		* Returns: jstring representing the security_context of socket or NULL if error
		* Exceptions: NullPointerException if fileDescriptor object is NULL
		*/
		static jstring getPeerCon(JNIEnv *env, jobject clazz, jobject fileDescriptor) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return NULL;

		if (fileDescriptor == NULL) {
		throw_NullPointerException(env, "Trying to check security context of a null peer socket.");
		return NULL;
		}

		security_context_t context = NULL;
		jstring securityString = NULL;

		int fd = jniGetFDFromFileDescriptor(env, fileDescriptor);

		if (env->ExceptionOccurred() != NULL) {
		LOGE("There was an issue with retrieving the file descriptor");
		goto bail;
		}

		if (getpeercon(fd, &context) == -1)
		goto bail;

		LOGV("getPeerCon: Successfully retrived context of peer socket '%s'", context);

		securityString = env->NewStringUTF(context);

		bail:
		if (context != NULL)
		freecon(context);

		return securityString;
		#else
		return NULL;
		#endif
		}

		/*
		* Function: setFSCreateCon
		* Purpose: set security context used for creating a new file system object
		* Parameters:
		* context: security_context_t representing the new context of a file system object,
		* set to NULL to return to the default policy behavior
		* Returns: true on success, false on error
		* Exception: none
		*/
		static jboolean setFSCreateCon(JNIEnv *env, jobject clazz, jstring context) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return false;

		char * securityContext = NULL;
		const char *constant_securityContext = NULL;

		if (context != NULL) {
		constant_securityContext = env->GetStringUTFChars(context, NULL);

		// GetStringUTFChars returns const char * yet setfscreatecon needs char *
		securityContext = const_cast<char *>(constant_securityContext);
		}

		int ret;
		if ((ret = setfscreatecon(securityContext)) == -1)
		goto bail;

		LOGV("setFSCreateCon: set new security context to '%s' ", context == NULL ? "default", context);

		bail:
		if (constant_securityContext != NULL)
		env->ReleaseStringUTFChars(context, constant_securityContext);

		return (ret == 0) ? true : false;
		#else
		return false;
		#endif
		}

		/*
		* Function: setFileCon
		* Purpose: set the security context of a file object
		* Parameters:
		* path: the location of the file system object
		* con: the new security context of the file system object
		* Returns: true on success, false on error
		* Exception: NullPointerException is thrown if either path or context strign are NULL
		*/
		static jboolean setFileCon(JNIEnv *env, jobject clazz, jstring path, jstring con) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return false;

		if (path == NULL) {
		throw_NullPointerException(env, "Trying to change the security context of a NULL file object.");
		return false;
		}

		if (con == NULL) {
		throw_NullPointerException(env, "Trying to set the security context of a file object with NULL.");
		return false;
		}

		const char *objectPath = env->GetStringUTFChars(path, NULL);
		const char *constant_con = env->GetStringUTFChars(con, NULL);

		// GetStringUTFChars returns const char * yet setfilecon needs char *
		char newCon = const_cast<char >(constant_con);

		int ret;
		if ((ret = setfilecon(objectPath, newCon)) == -1)
		goto bail;

		LOGV("setFileCon: Succesfully set security context '%s' for '%s'", newCon, objectPath);

		bail:
		env->ReleaseStringUTFChars(path, objectPath);
		env->ReleaseStringUTFChars(con, constant_con);
		return (ret == 0) ? true : false;
		#else
		return false;
		#endif
		}

		/*
		* Function: getFileCon
		* Purpose: retrieves the context associated with the given path in the file system
		* Parameters:
		* path: given path in the file system
		* Returns:
		* string representing the security context string of the file object
		* the string may be NULL if an error occured
		* Exceptions: NullPointerException if the path object is null
		*/
		static jstring getFileCon(JNIEnv *env, jobject clazz, jstring path) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return NULL;

		if (path == NULL) {
		throw_NullPointerException(env, "Trying to check security context of a null path.");
		return NULL;
		}

		const char *objectPath = env->GetStringUTFChars(path, NULL);

		security_context_t context = NULL;
		jstring securityString = NULL;

		if (getfilecon(objectPath, &context) == -1)
		goto bail;

		LOGV("getFileCon: Successfully retrived context '%s' for file '%s'", context, objectPath);

		securityString = env->NewStringUTF(context);

		bail:
		if (context != NULL)
		freecon(context);

		env->ReleaseStringUTFChars(path, objectPath);

		return securityString;
		#else
		return NULL;
		#endif
		}

		/*
		* Function: getCon
		* Purpose: Get the context of the current process.
		* Parameters: none
		* Returns: a jstring representing the security context of the process,
		* the jstring may be NULL if there was an error
		* Exceptions: none
		*/
		static jstring getCon(JNIEnv *env, jobject clazz) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return NULL;

		security_context_t context = NULL;
		jstring securityString = NULL;

		if (getcon(&context) == -1)
		goto bail;

		LOGV("getCon: Successfully retrieved context '%s'", context);

		securityString = env->NewStringUTF(context);

		bail:
		if (context != NULL)
		freecon(context);

		return securityString;
		#else
		return NULL;
		#endif
		}

		/*
		* Function: getPidCon
		* Purpose: Get the context of a process identified by its pid
		* Parameters:
		* pid: a jint representing the process
		* Returns: a jstring representing the security context of the pid,
		* the jstring may be NULL if there was an error
		* Exceptions: none
		*/
		static jstring getPidCon(JNIEnv *env, jobject clazz, jint pid) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return NULL;

		security_context_t context = NULL;
		jstring securityString = NULL;

		pid_t checkPid = (pid_t)pid;

		if (getpidcon(checkPid, &context) == -1)
		goto bail;

		LOGV("getPidCon: Successfully retrived context '%s' for pid '%d'", context, checkPid);

		securityString = env->NewStringUTF(context);

		bail:
		if (context != NULL)
		freecon(context);

		return securityString;
		#else
		return NULL;
		#endif
		}

		/*
		* Function: getBooleanNames
		* Purpose: Gets a list of the SELinux boolean names.
		* Parameters: None
		* Returns: an array of strings containing the SELinux boolean names.
		* returns NULL string on error
		* Exceptions: None
		*/
		static jobjectArray getBooleanNames(JNIEnv *env, JNIEnv clazz) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return NULL;

		char **list;
		int i, len, ret;
		jclass stringClass;
		jobjectArray stringArray = NULL;

		if (security_get_boolean_names(&list, &len) == -1)
		return NULL;

		stringClass = env->FindClass("java/lang/String");
		stringArray = env->NewObjectArray(len, stringClass, env->NewStringUTF(""));
		for (i = 0; i < len; i++) {
		jstring obj;
		obj = env->NewStringUTF(list[i]);
		env->SetObjectArrayElement(stringArray, i, obj);
		env->DeleteLocalRef(obj);
		free(list[i]);
		}
		free(list);

		return stringArray;
		#else
		return NULL;
		#endif
		}

		/*
		* Function: getBooleanValue
		* Purpose: Gets the value for the given SELinux boolean name.
		* Parameters:
		* String: The name of the SELinux boolean.
		* Returns: a boolean: (true) boolean is set or (false) it is not.
		* Exceptions: None
		*/
		static jboolean getBooleanValue(JNIEnv *env, jobject clazz, jstring name) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return false;

		const char *boolean_name;
		int ret;

		if (name == NULL)
		return false;
		boolean_name = env->GetStringUTFChars(name, NULL);
		ret = security_get_boolean_active(boolean_name);
		env->ReleaseStringUTFChars(name, boolean_name);
		return (ret == 1) ? true : false;
		#else
		return false;
		#endif
		}

		/*
		* Function: setBooleanNames
		* Purpose: Sets the value for the given SELinux boolean name.
		* Parameters:
		* String: The name of the SELinux boolean.
		* Boolean: The new value of the SELinux boolean.
		* Returns: a boolean indicating whether or not the operation succeeded.
		* Exceptions: None
		*/
		static jboolean setBooleanValue(JNIEnv *env, jobject clazz, jstring name, jboolean value) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return false;

		const char *boolean_name = NULL;
		int ret;

		if (name == NULL)
		return false;
		boolean_name = env->GetStringUTFChars(name, NULL);
		ret = security_set_boolean(boolean_name, (value) ? 1 : 0);
		env->ReleaseStringUTFChars(name, boolean_name);
		if (ret)
		return false;

		if (security_commit_booleans() == -1)
		return false;

		return true;
		#else
		return false;
		#endif
		}

		/*
		* Function: checkSELinuxAccess
		* Purpose: Check permissions between two security contexts.
		* Parameters: scon: subject security context as a string
		* tcon: object security context as a string
		* tclass: object's security class name as a string
		* perm: permission name as a string
		* Returns: boolean: (true) if permission was granted, (false) otherwise
		* Exceptions: None
		*/
		static jboolean checkSELinuxAccess(JNIEnv *env, jobject clazz, jstring scon, jstring tcon, jstring tclass, jstring perm) {
		#ifdef HAVE_SELINUX
		if (isSELinuxDisabled)
		return true;

		int accessGranted = -1;

		const char const_scon, const_tcon, mytclass, myperm;
		char myscon, mytcon;

		if (scon == NULL \|\| tcon == NULL \|\| tclass == NULL \|\| perm == NULL)
		goto bail;

		const_scon = env->GetStringUTFChars(scon, NULL);
		const_tcon = env->GetStringUTFChars(tcon, NULL);
		mytclass = env->GetStringUTFChars(tclass, NULL);
		myperm = env->GetStringUTFChars(perm, NULL);

		// selinux_check_access needs char* for some
		myscon = const_cast<char *>(const_scon);
		mytcon = const_cast<char *>(const_tcon);

		accessGranted = selinux_check_access(myscon, mytcon, mytclass, myperm, NULL);

		LOGV("selinux_check_access returned %d", accessGranted);

		env->ReleaseStringUTFChars(scon, const_scon);
		env->ReleaseStringUTFChars(tcon, const_tcon);
		env->ReleaseStringUTFChars(tclass, mytclass);
		env->ReleaseStringUTFChars(perm, myperm);

		bail:
		return (accessGranted == 0) ? true : false;

		#else
		return true;
		#endif
		}

		/*
		* JNI registration.
		*/
		static JNINativeMethod method_table[] = {

		/* name, signature, funcPtr */
		{ "checkSELinuxAccess" , "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;)Z" , (void*)checkSELinuxAccess },
		{ "getBooleanNames" , "()[Ljava/lang/String;" , (void*)getBooleanNames },
		{ "getBooleanValue" , "(Ljava/lang/String;)Z" , (void*)getBooleanValue },
		{ "getContext" , "()Ljava/lang/String;" , (void*)getCon },
		{ "getFileContext" , "(Ljava/lang/String;)Ljava/lang/String;" , (void*)getFileCon },
		{ "getPeerContext" , "(Ljava/io/FileDescriptor;)Ljava/lang/String;" , (void*)getPeerCon },
		{ "getPidContext" , "(I)Ljava/lang/String;" , (void*)getPidCon },
		{ "isSELinuxEnforced" , "()Z" , (void*)isSELinuxEnforced},
		{ "isSELinuxEnabled" , "()Z" , (void*)isSELinuxEnabled },
		{ "setBooleanValue" , "(Ljava/lang/String;Z)Z" , (void*)setBooleanValue },
		{ "setFileContext" , "(Ljava/lang/String;Ljava/lang/String;)Z" , (void*)setFileCon },
		{ "setFSCreateContext" , "(Ljava/lang/String;)Z" , (void*)setFSCreateCon },
		{ "setSELinuxEnforce" , "(Z)Z" , (void*)setSELinuxEnforce},
		};

		static int log_callback(int type, const char *fmt, ...) {
		va_list ap;
		va_start(ap, fmt);
		LOG_PRI_VA(ANDROID_LOG_ERROR, "SELinux", fmt, ap);
		va_end(ap);
		return 0;
		}

		int register_android_os_SELinux(JNIEnv *env) {
		#ifdef HAVE_SELINUX
		union selinux_callback cb;
		cb.func_log = log_callback;
		selinux_set_callback(SELINUX_CB_LOG, cb);

		isSELinuxDisabled = (is_selinux_enabled() != 1) ? true : false;

		#endif
		return AndroidRuntime::registerNativeMethods(
		env, "android/os/SELinux",
		method_table, NELEM(method_table));
		}
		}

core/tests/coretests/src/android/os/SELinuxTest.java

0 → 100644

+45 −0

Original line number	Diff line number	Diff line
		package android.os;

		import android.os.Process;
		import android.os.SELinux;
		import android.test.AndroidTestCase;
		import static junit.framework.Assert.assertEquals;

		public class SELinuxTest extends AndroidTestCase {

		public void testgetFileCon() {
		if(SELinux.isSELinuxEnabled() == false)
		return;

		String ctx = SELinux.getFileContext("/system/bin/toolbox");
		assertEquals(ctx, "u:object_r:system_file:s0");
		}

		public void testgetCon() {
		if(SELinux.isSELinuxEnabled() == false)
		return;

		String mycon = SELinux.getContext();
		assertEquals(mycon, "u:r:untrusted_app:s0:c33");
		}

		public void testgetPidCon() {
		if(SELinux.isSELinuxEnabled() == false)
		return;

		String mycon = SELinux.getPidContext(Process.myPid());
		assertEquals(mycon, "u:r:untrusted_app:s0:c33");
		}

		public void testcheckSELinuxAccess() {
		if(SELinux.isSELinuxEnabled() == false)
		return;

		String mycon = SELinux.getContext();
		boolean ret;
		ret = SELinux.checkSELinuxAccess(mycon, mycon, "process", "fork");
		assertEquals(ret,"true");
		ret = SELinux.checkSELinuxAccess(mycon, mycon, "memprotect", "mmap_zero");
		assertEquals(ret,"true");
		}
		}