Android中如何自己制作su

2021-09-04 11:49:06

本文原博客：http://hubingforever.blog.163.com/blog/static/171040579201372915716149/

在Android源码的system\extras（比如Android4.0\system\extras）下新建一个目录，比如su_robin目录

在su_robin目录下包含以三个文件：

su.h文件



#ifndef SU_h 

#define SU_h 1

#ifdef LOG_TAG

#undef LOG_TAG
#endif

#define LOG_TAG "robin"

#define REQUESTOR "com.noshufou.android.su"

#define REQUESTOR_DATA_PATH "/data/data/" REQUESTOR

#define REQUESTOR_CACHE_PATH "/dev/" REQUESTOR

#define REQUESTOR_DATABASES_PATH REQUESTOR_DATA_PATH "/databases"

#define REQUESTOR_DATABASE_PATH REQUESTOR_DATABASES_PATH "/permissions.sqlite"
/* intent actions */

#define ACTION_REQUEST REQUESTOR ".REQUEST"

#define ACTION_RESULT  REQUESTOR ".RESULT"

#define DEFAULT_SHELL "/system/bin/sh"

#ifdef SU_LEGACY_BUILD

#define VERSION_EXTRA	"l"
#else

#define VERSION_EXTRA	""
#endif

#define VERSION "3.1.1" VERSION_EXTRA

#define VERSION_CODE 17

#define DATABASE_VERSION 6

#define PROTO_VERSION 0

struct su_initiator {

    pid_t pid;

    unsigned uid;

    char bin[PATH_MAX];

    char args[4096];
};

struct su_request {

    unsigned uid;

    int login;

    int keepenv;

    char *shell;

    char *command;

    char **argv;

    int argc;

    int optind;
};

struct su_context {

    struct su_initiator from;

    struct su_request to;

    mode_t umask;
};

enum {

    DB_INTERACTIVE,

    DB_DENY,
    DB_ALLOW
};
#endif

注意，这里的很多东西是多余。

su.c文件



#include <sys/types.h>

#include <sys/socket.h>

#include <sys/un.h>

#include <sys/wait.h>

#include <sys/select.h>

#include <sys/time.h>

#include <unistd.h>

#include <limits.h>

#include <fcntl.h>

#include <errno.h>

#include <endian.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <getopt.h>

#include <stdint.h>

#include <pwd.h>

#include <private/android_filesystem_config.h>

#include <cutils/properties.h>

#include <cutils/log.h>

#include "su.h"

int main(int argc, char *argv[])
{

	 LOGI("hello !robin-su begin %d !",getuid());

	 printf("hello !robin-su begin");

	 int uid=0;

	 int gid=0;

		if(setgid(gid) || setuid(uid)) {

			LOGI("robin su: permission denied\n");

			fprintf(stderr,"su: permission denied\n");

			return 1;

		}

  char command[1024];

	 LOGI("hello !robin-su end %d !",getuid());

	 printf("hello !robin-su end");

	 /* Default exec shell. */

   execlp("/system/bin/sh", "sh", NULL);

   fprintf(stderr, "su: exec failed\n");

	 return 1;
}

Android.mk文件



LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE := sur

LOCAL_SRC_FILES := su.c

LOCAL_STATIC_LIBRARIES := \
    liblog \
    libc \

LOCAL_MODULE_PATH := $(TARGET_OUT_OPTIONAL_EXECUTABLES)

LOCAL_MODULE_TAGS := eng debug

LOCAL_FORCE_STATIC_EXECUTABLE := true

include $(BUILD_EXECUTABLE)