core/jni/com_android_internal_os_ZygoteInit.cpp - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2007 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.
  */

 #define LOG_TAG "Zygote"

 #include <sys/types.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <utils/misc.h>
 #include <errno.h>
 #include <sys/select.h>

 #include "jni.h"
 #include <JNIHelp.h>
 #include "android_runtime/AndroidRuntime.h"

 #include <linux/capability.h>
 #include <linux/prctl.h>
 #include <sys/prctl.h>
 extern "C" int capget(cap_user_header_t hdrp, cap_user_data_t datap);
 extern "C" int capset(cap_user_header_t hdrp, const cap_user_data_t datap);


 namespace android {

 /*
  * In class com.android.internal.os.ZygoteInit:
  * private static native boolean setreuid(int ruid, int euid)
  */
 static jint com_android_internal_os_ZygoteInit_setreuid(
     JNIEnv* env, jobject clazz, jint ruid, jint euid)
 {
     if (setreuid(ruid, euid) < 0) {
         return errno;
     }
     return 0;
 }

 /*
  * In class com.android.internal.os.ZygoteInit:
  * private static native int setregid(int rgid, int egid)
  */
 static jint com_android_internal_os_ZygoteInit_setregid(
     JNIEnv* env, jobject clazz, jint rgid, jint egid)
 {
     if (setregid(rgid, egid) < 0) {
         return errno;
     }
     return 0;
 }

 /*
  * In class com.android.internal.os.ZygoteInit:
  * private static native int setpgid(int rgid, int egid)
  */
 static jint com_android_internal_os_ZygoteInit_setpgid(
     JNIEnv* env, jobject clazz, jint pid, jint pgid)
 {
     if (setpgid(pid, pgid) < 0) {
         return errno;
     }
     return 0;
 }

 /*
  * In class com.android.internal.os.ZygoteInit:
  * private static native int getpgid(int pid)
  */
 static jint com_android_internal_os_ZygoteInit_getpgid(
     JNIEnv* env, jobject clazz, jint pid)
 {
     pid_t ret;
     ret = getpgid(pid);

     if (ret < 0) {
         jniThrowIOException(env, errno);
     }

     return ret;
 }

 static void com_android_internal_os_ZygoteInit_reopenStdio(JNIEnv* env,
         jobject clazz, jobject in, jobject out, jobject errfd)
 {
     int fd;
     int err;

     fd = jniGetFDFromFileDescriptor(env, in);

     if  (env->ExceptionOccurred() != NULL) {
         return;
     }

     do {
         err = dup2(fd, STDIN_FILENO);
     } while (err < 0 && errno == EINTR);

     fd = jniGetFDFromFileDescriptor(env, out);

     if  (env->ExceptionOccurred() != NULL) {
         return;
     }

     do {
         err = dup2(fd, STDOUT_FILENO);
     } while (err < 0 && errno == EINTR);

     fd = jniGetFDFromFileDescriptor(env, errfd);

     if  (env->ExceptionOccurred() != NULL) {
         return;
     }

     do {
         err = dup2(fd, STDERR_FILENO);
     } while (err < 0 && errno == EINTR);
 }

 static void com_android_internal_os_ZygoteInit_setCloseOnExec (JNIEnv *env,
     jobject clazz, jobject descriptor, jboolean flag)
 {
     int fd;
     int err;
     int fdFlags;

     fd = jniGetFDFromFileDescriptor(env, descriptor);

     if  (env->ExceptionOccurred() != NULL) {
         return;
     }

     fdFlags = fcntl(fd, F_GETFD);

     if (fdFlags < 0) {
         jniThrowIOException(env, errno);
         return;
     }

     if (flag) {
         fdFlags |= FD_CLOEXEC;
     } else {
         fdFlags &= ~FD_CLOEXEC;
     }

     err = fcntl(fd, F_SETFD, fdFlags);

     if (err < 0) {
         jniThrowIOException(env, errno);
         return;
     }
 }

 static void com_android_internal_os_ZygoteInit_setCapabilities (JNIEnv *env,
     jobject clazz, jlong permitted, jlong effective)
 {
     struct __user_cap_header_struct capheader;
     struct __user_cap_data_struct capdata;
     int err;

     memset (&capheader, 0, sizeof(capheader));
     memset (&capdata, 0, sizeof(capdata));

     capheader.version = _LINUX_CAPABILITY_VERSION;
     capheader.pid = 0;

     // As of this writing, capdata is __u32, but that's expected
     // to change...
     capdata.effective = effective;
     capdata.permitted = permitted;

     err = capset (&capheader, &capdata);

     if (err < 0) {
         jniThrowIOException(env, errno);
         return;
     }
 }

 static jlong com_android_internal_os_ZygoteInit_capgetPermitted (JNIEnv *env,
     jobject clazz, jint pid)
 {
     struct __user_cap_header_struct capheader;
     struct __user_cap_data_struct capdata;
     int err;

     memset (&capheader, 0, sizeof(capheader));
     memset (&capdata, 0, sizeof(capdata));

     capheader.version = _LINUX_CAPABILITY_VERSION;
     capheader.pid = pid;

     err = capget (&capheader, &capdata);

     if (err < 0) {
         jniThrowIOException(env, errno);
         return 0;
     }

     return (jlong) capdata.permitted;
 }

 static jint com_android_internal_os_ZygoteInit_selectReadable (
         JNIEnv *env, jobject clazz, jobjectArray fds)
 {
     if (fds == NULL) {
         jniThrowNullPointerException(env, "fds == null");
         return -1;
     }

     jsize length = env->GetArrayLength(fds);
     fd_set fdset;

     if (env->ExceptionOccurred() != NULL) {
         return -1;
     }

     FD_ZERO(&fdset);

     int nfds = 0;
     for (jsize i = 0; i < length; i++) {
         jobject fdObj = env->GetObjectArrayElement(fds, i);
         if  (env->ExceptionOccurred() != NULL) {
             return -1;
         }
         if (fdObj == NULL) {
             continue;
         }
         int fd = jniGetFDFromFileDescriptor(env, fdObj);
         if  (env->ExceptionOccurred() != NULL) {
             return -1;
         }

         FD_SET(fd, &fdset);

         if (fd >= nfds) {
             nfds = fd + 1;
         }
     }

     int err;
     do {
         err = select (nfds, &fdset, NULL, NULL, NULL);
     } while (err < 0 && errno == EINTR);

     if (err < 0) {
         jniThrowIOException(env, errno);
         return -1;
     }

     for (jsize i = 0; i < length; i++) {
         jobject fdObj = env->GetObjectArrayElement(fds, i);
         if  (env->ExceptionOccurred() != NULL) {
             return -1;
         }
         if (fdObj == NULL) {
             continue;
         }
         int fd = jniGetFDFromFileDescriptor(env, fdObj);
         if  (env->ExceptionOccurred() != NULL) {
             return -1;
         }
         if (FD_ISSET(fd, &fdset)) {
             return (jint)i;
         }
     }
     return -1;
 }

 static jobject com_android_internal_os_ZygoteInit_createFileDescriptor (
         JNIEnv *env, jobject clazz, jint fd)
 {
     return jniCreateFileDescriptor(env, fd);
 }

 /*
  * JNI registration.
  */
 static JNINativeMethod gMethods[] = {
     /* name, signature, funcPtr */
     { "setreuid", "(II)I",
       (void*) com_android_internal_os_ZygoteInit_setreuid },
     { "setregid", "(II)I",
       (void*) com_android_internal_os_ZygoteInit_setregid },
     { "setpgid", "(II)I",
       (void *) com_android_internal_os_ZygoteInit_setpgid },
     { "getpgid", "(I)I",
       (void *) com_android_internal_os_ZygoteInit_getpgid },
     { "reopenStdio",
         "(Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;"
         "Ljava/io/FileDescriptor;)V",
             (void *) com_android_internal_os_ZygoteInit_reopenStdio},
     { "setCloseOnExec", "(Ljava/io/FileDescriptor;Z)V",
         (void *)  com_android_internal_os_ZygoteInit_setCloseOnExec},
     { "setCapabilities", "(JJ)V",
         (void *) com_android_internal_os_ZygoteInit_setCapabilities },
     { "capgetPermitted", "(I)J",
         (void *) com_android_internal_os_ZygoteInit_capgetPermitted },
     { "selectReadable", "([Ljava/io/FileDescriptor;)I",
         (void *) com_android_internal_os_ZygoteInit_selectReadable },
     { "createFileDescriptor", "(I)Ljava/io/FileDescriptor;",
         (void *) com_android_internal_os_ZygoteInit_createFileDescriptor }
 };
 int register_com_android_internal_os_ZygoteInit(JNIEnv* env)
 {
     return AndroidRuntime::registerNativeMethods(env,
             "com/android/internal/os/ZygoteInit", gMethods, NELEM(gMethods));
 }

 }; // namespace android
	/*
	* Copyright (C) 2007 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.
	*/

	#define LOG_TAG "Zygote"

	#include <sys/types.h>
	#include <unistd.h>
	#include <fcntl.h>
	#include <utils/misc.h>
	#include <errno.h>
	#include <sys/select.h>

	#include "jni.h"
	#include <JNIHelp.h>
	#include "android_runtime/AndroidRuntime.h"

	#include <linux/capability.h>
	#include <linux/prctl.h>
	#include <sys/prctl.h>
	extern "C" int capget(cap_user_header_t hdrp, cap_user_data_t datap);
	extern "C" int capset(cap_user_header_t hdrp, const cap_user_data_t datap);


	namespace android {

	/*
	* In class com.android.internal.os.ZygoteInit:
	* private static native boolean setreuid(int ruid, int euid)
	*/
	static jint com_android_internal_os_ZygoteInit_setreuid(
	JNIEnv* env, jobject clazz, jint ruid, jint euid)
	{
	if (setreuid(ruid, euid) < 0) {
	return errno;
	}
	return 0;
	}

	/*
	* In class com.android.internal.os.ZygoteInit:
	* private static native int setregid(int rgid, int egid)
	*/
	static jint com_android_internal_os_ZygoteInit_setregid(
	JNIEnv* env, jobject clazz, jint rgid, jint egid)
	{
	if (setregid(rgid, egid) < 0) {
	return errno;
	}
	return 0;
	}

	/*
	* In class com.android.internal.os.ZygoteInit:
	* private static native int setpgid(int rgid, int egid)
	*/
	static jint com_android_internal_os_ZygoteInit_setpgid(
	JNIEnv* env, jobject clazz, jint pid, jint pgid)
	{
	if (setpgid(pid, pgid) < 0) {
	return errno;
	}
	return 0;
	}

	/*
	* In class com.android.internal.os.ZygoteInit:
	* private static native int getpgid(int pid)
	*/
	static jint com_android_internal_os_ZygoteInit_getpgid(
	JNIEnv* env, jobject clazz, jint pid)
	{
	pid_t ret;
	ret = getpgid(pid);

	if (ret < 0) {
	jniThrowIOException(env, errno);
	}

	return ret;
	}

	static void com_android_internal_os_ZygoteInit_reopenStdio(JNIEnv* env,
	jobject clazz, jobject in, jobject out, jobject errfd)
	{
	int fd;
	int err;

	fd = jniGetFDFromFileDescriptor(env, in);

	if (env->ExceptionOccurred() != NULL) {
	return;
	}

	do {
	err = dup2(fd, STDIN_FILENO);
	} while (err < 0 && errno == EINTR);

	fd = jniGetFDFromFileDescriptor(env, out);

	if (env->ExceptionOccurred() != NULL) {
	return;
	}

	do {
	err = dup2(fd, STDOUT_FILENO);
	} while (err < 0 && errno == EINTR);

	fd = jniGetFDFromFileDescriptor(env, errfd);

	if (env->ExceptionOccurred() != NULL) {
	return;
	}

	do {
	err = dup2(fd, STDERR_FILENO);
	} while (err < 0 && errno == EINTR);
	}

	static void com_android_internal_os_ZygoteInit_setCloseOnExec (JNIEnv *env,
	jobject clazz, jobject descriptor, jboolean flag)
	{
	int fd;
	int err;
	int fdFlags;

	fd = jniGetFDFromFileDescriptor(env, descriptor);

	if (env->ExceptionOccurred() != NULL) {
	return;
	}

	fdFlags = fcntl(fd, F_GETFD);

	if (fdFlags < 0) {
	jniThrowIOException(env, errno);
	return;
	}

	if (flag) {
	fdFlags \|= FD_CLOEXEC;
	} else {
	fdFlags &= ~FD_CLOEXEC;
	}

	err = fcntl(fd, F_SETFD, fdFlags);

	if (err < 0) {
	jniThrowIOException(env, errno);
	return;
	}
	}

	static void com_android_internal_os_ZygoteInit_setCapabilities (JNIEnv *env,
	jobject clazz, jlong permitted, jlong effective)
	{
	struct __user_cap_header_struct capheader;
	struct __user_cap_data_struct capdata;
	int err;

	memset (&capheader, 0, sizeof(capheader));
	memset (&capdata, 0, sizeof(capdata));

	capheader.version = _LINUX_CAPABILITY_VERSION;
	capheader.pid = 0;

	// As of this writing, capdata is __u32, but that's expected
	// to change...
	capdata.effective = effective;
	capdata.permitted = permitted;

	err = capset (&capheader, &capdata);

	if (err < 0) {
	jniThrowIOException(env, errno);
	return;
	}
	}

	static jlong com_android_internal_os_ZygoteInit_capgetPermitted (JNIEnv *env,
	jobject clazz, jint pid)
	{
	struct __user_cap_header_struct capheader;
	struct __user_cap_data_struct capdata;
	int err;

	memset (&capheader, 0, sizeof(capheader));
	memset (&capdata, 0, sizeof(capdata));

	capheader.version = _LINUX_CAPABILITY_VERSION;
	capheader.pid = pid;

	err = capget (&capheader, &capdata);

	if (err < 0) {
	jniThrowIOException(env, errno);
	return 0;
	}

	return (jlong) capdata.permitted;
	}

	static jint com_android_internal_os_ZygoteInit_selectReadable (
	JNIEnv *env, jobject clazz, jobjectArray fds)
	{
	if (fds == NULL) {
	jniThrowNullPointerException(env, "fds == null");
	return -1;
	}

	jsize length = env->GetArrayLength(fds);
	fd_set fdset;

	if (env->ExceptionOccurred() != NULL) {
	return -1;
	}

	FD_ZERO(&fdset);

	int nfds = 0;
	for (jsize i = 0; i < length; i++) {
	jobject fdObj = env->GetObjectArrayElement(fds, i);
	if (env->ExceptionOccurred() != NULL) {
	return -1;
	}
	if (fdObj == NULL) {
	continue;
	}
	int fd = jniGetFDFromFileDescriptor(env, fdObj);
	if (env->ExceptionOccurred() != NULL) {
	return -1;
	}

	FD_SET(fd, &fdset);

	if (fd >= nfds) {
	nfds = fd + 1;
	}
	}

	int err;
	do {
	err = select (nfds, &fdset, NULL, NULL, NULL);
	} while (err < 0 && errno == EINTR);

	if (err < 0) {
	jniThrowIOException(env, errno);
	return -1;
	}

	for (jsize i = 0; i < length; i++) {
	jobject fdObj = env->GetObjectArrayElement(fds, i);
	if (env->ExceptionOccurred() != NULL) {
	return -1;
	}
	if (fdObj == NULL) {
	continue;
	}
	int fd = jniGetFDFromFileDescriptor(env, fdObj);
	if (env->ExceptionOccurred() != NULL) {
	return -1;
	}
	if (FD_ISSET(fd, &fdset)) {
	return (jint)i;
	}
	}
	return -1;
	}

	static jobject com_android_internal_os_ZygoteInit_createFileDescriptor (
	JNIEnv *env, jobject clazz, jint fd)
	{
	return jniCreateFileDescriptor(env, fd);
	}

	/*
	* JNI registration.
	*/
	static JNINativeMethod gMethods[] = {
	/* name, signature, funcPtr */
	{ "setreuid", "(II)I",
	(void*) com_android_internal_os_ZygoteInit_setreuid },
	{ "setregid", "(II)I",
	(void*) com_android_internal_os_ZygoteInit_setregid },
	{ "setpgid", "(II)I",
	(void *) com_android_internal_os_ZygoteInit_setpgid },
	{ "getpgid", "(I)I",
	(void *) com_android_internal_os_ZygoteInit_getpgid },
	{ "reopenStdio",
	"(Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;"
	"Ljava/io/FileDescriptor;)V",
	(void *) com_android_internal_os_ZygoteInit_reopenStdio},
	{ "setCloseOnExec", "(Ljava/io/FileDescriptor;Z)V",
	(void *) com_android_internal_os_ZygoteInit_setCloseOnExec},
	{ "setCapabilities", "(JJ)V",
	(void *) com_android_internal_os_ZygoteInit_setCapabilities },
	{ "capgetPermitted", "(I)J",
	(void *) com_android_internal_os_ZygoteInit_capgetPermitted },
	{ "selectReadable", "([Ljava/io/FileDescriptor;)I",
	(void *) com_android_internal_os_ZygoteInit_selectReadable },
	{ "createFileDescriptor", "(I)Ljava/io/FileDescriptor;",
	(void *) com_android_internal_os_ZygoteInit_createFileDescriptor }
	};
	int register_com_android_internal_os_ZygoteInit(JNIEnv* env)
	{
	return AndroidRuntime::registerNativeMethods(env,
	"com/android/internal/os/ZygoteInit", gMethods, NELEM(gMethods));
	}

	}; // namespace android