Android6.0 X86 ARM64位可用的注入Inject

最近在网上搜索Android的Inject与Hook，发现很多都因为时间久远而失效了，试了很多方案，最终找到了一个，特地来转载分享一下，本人的三星S6 6.0.1系统测试可用,另外4.2 4.4也都测试通过。

另外加上了注释便于大家理解。

转自 http://blog.csdn.net/jinzhuojun/article/details/9900105

1.inject.c

#include <stdio.h>    
#include <stdlib.h>    
#include <sys/user.h>    
#include <asm/ptrace.h>    
#include <sys/ptrace.h>    
#include <sys/wait.h>    
#include <sys/mman.h>    
#include <dlfcn.h>    
#include <dirent.h>    
#include <unistd.h>    
#include <string.h>    
#include <elf.h>    
#include <android/log.h>    
#include <sys/uio.h>

#if defined(__i386__)    
#define pt_regs         user_regs_struct    
#elif defined(__aarch64__)
#define pt_regs         user_pt_regs  
#define uregsregs
#define ARM_pcpc
#define ARM_spsp
#define ARM_cpsrpstate
#define ARM_lrregs[30]
#define ARM_r0regs[0]  
#define PTRACE_GETREGS PTRACE_GETREGSET
#define PTRACE_SETREGS PTRACE_SETREGSET
#endif    

#define ENABLE_DEBUG 1    

#if ENABLE_DEBUG    
#define  LOG_TAG "INJECT"    
#define  LOGD(fmt, args...)  __android_log_print(ANDROID_LOG_DEBUG,LOG_TAG, fmt, ##args)    
#define DEBUG_PRINT(format,args...) \    
    LOGD(format, ##args)    
#else    
#define DEBUG_PRINT(format,args...)    
#endif    

#define CPSR_T_MASK     ( 1u << 5 )    

#if defined(__aarch64__)    
const char *libc_path = "/system/lib64/libc.so";    
const char *linker_path = "/system/bin/linker64";    
#else
const char *libc_path = "/system/lib/libc.so";    
const char *linker_path = "/system/bin/linker";    
#endif

int ptrace_readdata(pid_t pid,  uint8_t *src, uint8_t *buf, size_t size)    
{    
    long i, j, remain;    
    uint8_t *laddr;       
    size_t bytes_width = sizeof(long);

    union u {    
        long val;    
        char chars[bytes_width];    
    } d;    

    j = size / bytes_width;    
    remain = size % bytes_width;    

    laddr = buf;    

    for (i = 0; i < j; i ++) {    
        d.val = ptrace(PTRACE_PEEKTEXT, pid, src, 0);    
        memcpy(laddr, d.chars, bytes_width);    
        src += bytes_width;    
        laddr += bytes_width;    
    }    

    if (remain > 0) {    
        d.val = ptrace(PTRACE_PEEKTEXT, pid, src, 0);    
        memcpy(laddr, d.chars, remain);    
    }    

    return 0;    
}    

/*
Func : 将size字节的data数据写入到pid进程的dest地址处
@param dest: 目的进程的栈地址
@param data: 需要写入的数据的起始地址
@param size: 需要写入的数据的大小，以字节为单位
*/
int ptrace_writedata(pid_t pid, uint8_t *dest, uint8_t *data, size_t size)    
{    
    long i, j, remain;    
    uint8_t *laddr;    
    size_t bytes_width = sizeof(long);

//很巧妙的联合体，这样就可以方便的以字节为单位写入4字节数据，再以long为单位ptrace_poketext到栈中  
    union u {    
        long val;    
        char chars[bytes_width];    
    } d;    

    j = size / bytes_width;    
    remain = size % bytes_width;    

    laddr = data;

//先以4字节为单位进行数据写入

    for (i = 0; i < j; i ++) {    
        memcpy(d.chars, laddr, bytes_width);    
        ptrace(PTRACE_POKETEXT, pid, dest, d.val);    

        dest  += bytes_width;    
        laddr += bytes_width;    
    }    

    if (remain > 0) {
//为了最大程度的保持原栈的数据，先读取dest的long数据，然后只更改其中的前remain字节，再写回
        d.val = ptrace(PTRACE_PEEKTEXT, pid, dest, 0);    
        for (i = 0; i < remain; i ++) {    
            d.chars[i] = *laddr ++;    
        }    

        ptrace(PTRACE_POKETEXT, pid, dest, d.val);   
    }    

    return 0;    
}    

/*
功能总结：
1，将要执行的指令写入寄存器中，指令长度大于4个long的话，需要将剩余的指令通过ptrace_writedata函数写入栈中；
2，使用ptrace_continue函数运行目的进程，直到目的进程返回状态值0xb7f（对该值的分析见后面红字）；
3，函数执行完之后，目标进程挂起，使用ptrace_getregs函数获取当前的所有寄存器值，方便后面使用ptrace_retval函数获取函数的返回值。
*/
#if defined(__arm__) || defined(__aarch64__)
int ptrace_call(pid_t pid, uintptr_t addr, long *params, int num_params, struct pt_regs* regs)    
{    
    int i;   
#if defined(__arm__) 
    int num_param_registers = 4;
#elif defined(__aarch64__) 
    int num_param_registers = 8;
#endif

    for (i = 0; i < num_params && i < num_param_registers; i ++) {    
        regs->uregs[i] = params[i];    
    }    

    //    
    // push remained params onto stack    
    //    
    if (i < num_params) {    
        regs->ARM_sp -= (num_params - i) * sizeof(long) ;    
        ptrace_writedata(pid, (void *)regs->ARM_sp,(uint8_t *)& params[i], (num_params - i) * sizeof(long));    
    }    
    //将PC寄存器值设为目标函数的地址
    regs->ARM_pc = addr; 
//进行指令集判断 
    if (regs->ARM_pc & 1) {    
        /* thumb */    
        regs->ARM_pc &= (~1u);    
// #define CPSR_T_MASK  ( 1u << 5 )  CPSR为程序状态寄存器
        regs->ARM_cpsr |= CPSR_T_MASK;    
    } else {    
        /* arm */    
        regs->ARM_cpsr &= ~CPSR_T_MASK;    
    }    

    //设置子程序的返回地址为空，以便函数执行完后，返回到null地址，产生SIGSEGV错误，详细作用见后面的红字分析
    regs->ARM_lr = 0;    

/*
    *Ptrace_setregs就是将修改后的regs写入寄存器中，然后调用ptrace_continue来执行我们指定的代码
    */
    if (ptrace_setregs(pid, regs) == -1     
            || ptrace_continue(pid) == -1) {    
        printf("error\n");    
        return -1;    
    }    

    int stat = 0;  
    waitpid(pid, &stat, WUNTRACED);  
/* WUNTRACED告诉waitpid，如果子进程进入暂停状态，那么就立即返回。如果是被ptrace的子进程，那么即使不提供WUNTRACED参数，也会在子进程进入暂停状态的时候立即返回。
对于使用ptrace_cont运行的子进程，它会在3种情况下进入暂停状态：①下一次系统调用；②子进程退出；③子进程的执行发生错误。这里的0xb7f就表示子进程进入了暂停状态，且发送的错误信号为11(SIGSEGV)，它表示试图访问未分配给自己的内存, 或试图往没有写权限的内存地址写数据。那么什么时候会发生这种错误呢？显然，当子进程执行完注入的函数后，由于我们在前面设置了regs->ARM_lr = 0，它就会返回到0地址处继续执行，这样就会产生SIGSEGV了！*/

//这个循环是否必须我还不确定。因为目前每次ptrace_call调用必定会返回0xb7f，不过在这也算是增加容错性吧~

//通过看ndk的源码sys/wait.h以及man waitpid可以知道这个0xb7f的具体作用。首先说一下stat的值：高2字节用于表示导致子进程的退出或暂停状态信号值，低2字节表示子进程是退出(0x0)还是暂停(0x7f)状态。0xb7f就表示子进程为暂停状态，导致它暂停的信号量为11即sigsegv错误。
while (stat != 0xb7f) {  
        if (ptrace_continue(pid) == -1) {  
            printf("error\n");  
            return -1;  
        }  
        waitpid(pid, &stat, WUNTRACED);  
    }  

    return 0;    
}    

#elif defined(__i386__)    
long ptrace_call(pid_t pid, uintptr_t addr, long *params, int num_params, struct user_regs_struct * regs)    
{    
    regs->esp -= (num_params) * sizeof(long) ;    
    ptrace_writedata(pid, (void *)regs->esp, (uint8_t *)params, (num_params) * sizeof(long));    

    long tmp_addr = 0x00;    
    regs->esp -= sizeof(long);    
    ptrace_writedata(pid, regs->esp, (char *)&tmp_addr, sizeof(tmp_addr));     

    regs->eip = addr;    

    if (ptrace_setregs(pid, regs) == -1     
            || ptrace_continue( pid) == -1) {    
        printf("error\n");    
        return -1;    
    }    

    int stat = 0;  
    waitpid(pid, &stat, WUNTRACED);  
    while (stat != 0xb7f) {  
        if (ptrace_continue(pid) == -1) {  
            printf("error\n");  
            return -1;  
        }  
        waitpid(pid, &stat, WUNTRACED);  
    }  

    return 0;    
}    
#else     
#error "Not supported"    
#endif    

int ptrace_getregs(pid_t pid, struct pt_regs * regs)    
{    
#if defined (__aarch64__)
int regset = NT_PRSTATUS;
struct iovec ioVec;

ioVec.iov_base = regs;
ioVec.iov_len = sizeof(*regs);
    if (ptrace(PTRACE_GETREGSET, pid, (void*)regset, &ioVec) < 0) {    
        perror("ptrace_getregs: Can not get register values");   
        printf(" io %llx, %d", ioVec.iov_base, ioVec.iov_len); 
        return -1;    
    }    

    return 0;   
#else
    if (ptrace(PTRACE_GETREGS, pid, NULL, regs) < 0) {    
        perror("ptrace_getregs: Can not get register values");    
        return -1;    
    }    

    return 0;   
#endif     
}    

int ptrace_setregs(pid_t pid, struct pt_regs * regs)    
{     
#if defined (__aarch64__)
int regset = NT_PRSTATUS;
struct iovec ioVec;

ioVec.iov_base = regs;
ioVec.iov_len = sizeof(*regs);
    if (ptrace(PTRACE_SETREGSET, pid, (void*)regset, &ioVec) < 0) {    
        perror("ptrace_setregs: Can not get register values");    
        return -1;    
    }    

    return 0;   
#else
    if (ptrace(PTRACE_SETREGS, pid, NULL, regs) < 0) {    
        perror("ptrace_setregs: Can not set register values");    
        return -1;    
    }    

    return 0;   
#endif     
}    

int ptrace_continue(pid_t pid)    
{    
    if (ptrace(PTRACE_CONT, pid, NULL, 0) < 0) {    
        perror("ptrace_cont");    
        return -1;    
    }    

    return 0;    
}    

int ptrace_attach(pid_t pid)    
{    
    if (ptrace(PTRACE_ATTACH, pid, NULL, 0) < 0) {    
        perror("ptrace_attach");    
        return -1;    
    }    

    int status = 0;    
    waitpid(pid, &status , WUNTRACED);    

    return 0;    
}    

int ptrace_detach(pid_t pid)    
{    
    if (ptrace(PTRACE_DETACH, pid, NULL, 0) < 0) {    
        perror("ptrace_detach");    
        return -1;    
    }    

    return 0;    
}


//显然，这里面核心的就是get_module_base函数：
/*
此函数的功能就是通过遍历/proc/pid/maps文件，来找到目的module_name的内存映射起始地址。
由于内存地址的表达方式是startAddrxxxxxxx-endAddrxxxxxxx的，所以会在后面使用strtok(line,"-")来分割字符串
如果pid = -1,表示获取本地进程的某个模块的地址，
否则就是pid进程的某个模块的地址。
*/    

void* get_module_base(pid_t pid, const char* module_name)    
{    
    FILE *fp;    
    long addr = 0;    
    char *pch;    
    char filename[32];    
    char line[1024];    

    if (pid < 0) {    
        /* self process */    
        snprintf(filename, sizeof(filename), "/proc/self/maps", pid);    
    } else {    
        snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);    
    }    

    fp = fopen(filename, "r");    

    if (fp != NULL) {    
        while (fgets(line, sizeof(line), fp)) {    
            if (strstr(line, module_name)) {
//分解字符串为一组字符串。line为要分解的字符串，"-"为分隔符字符串。
                pch = strtok( line, "-" );
//将参数pch字符串根据参数base(表示进制)来转换成无符号的长整型数  
                addr = strtoull( pch, NULL, 16 );   

                if (addr == 0x8000)    
                    addr = 0;    

                break;    
            }    
        }    

        fclose(fp) ;    
    }    

    return (void *)addr;    
}    

/*
该函数为一个封装函数，通过调用get_module_base函数来获取目的进程的某个模块的起始地址，然后通过公式计算出指定函数在目的进程的起始地址。
*/
void* get_remote_addr(pid_t target_pid, const char* module_name, void* local_addr)    
{    
    void* local_handle, *remote_handle; 

//获取本地某个模块的起始地址
    local_handle = get_module_base(-1, module_name);
    //获取远程pid的某个模块的起始地址
    remote_handle = get_module_base(target_pid, module_name);    

    DEBUG_PRINT("[+] get_remote_addr: local[%llx], remote[%llx]\n", local_handle, remote_handle);    
    /*这需要我们好好理解：local_addr - local_handle的值为指定函数(如mmap)在该模块中的偏移量，然后再加上rempte_handle，结果就为指定函数在目的进程的虚拟地址*/
    void * ret_addr = (void *)((uintptr_t)local_addr + (uintptr_t)remote_handle - (uintptr_t)local_handle);    

#if defined(__i386__)    
    if (!strcmp(module_name, libc_path)) {    
        ret_addr += 2;    
    }    
#endif    
    return ret_addr;    
}    

//根据name找到pid
int find_pid_of(const char *process_name)    
{    
    int id;    
    pid_t pid = -1;    
    DIR* dir;    
    FILE *fp;    
    char filename[32];    
    char cmdline[256];    

    struct dirent * entry;    

    if (process_name == NULL)    
        return -1;    

    dir = opendir("/proc");    
    if (dir == NULL)    
        return -1;    

    while((entry = readdir(dir)) != NULL) {    
        id = atoi(entry->d_name);    
        if (id != 0) {    
            sprintf(filename, "/proc/%d/cmdline", id);    
            fp = fopen(filename, "r");    
            if (fp) {    
                fgets(cmdline, sizeof(cmdline), fp);    
                fclose(fp);    

                if (strcmp(process_name, cmdline) == 0) {    
                    /* process found */    
                    pid = id;    
                    break;    
                }    
            }    
        }    
    }    

    closedir(dir);    
    return pid;    
}    

uint64_t ptrace_retval(struct pt_regs * regs)    
{    
#if defined(__arm__) || defined(__aarch64__)
    return regs->ARM_r0;    
#elif defined(__i386__)    
    return regs->eax;    
#else    
#error "Not supported"    
#endif    
}    

uint64_t ptrace_ip(struct pt_regs * regs)    
{    
#if defined(__arm__) || defined(__aarch64__) 
    return regs->ARM_pc;   
#elif defined(__i386__)    
    return regs->eip;    
#else    
#error "Not supported"    
#endif    
}    

//总结一下ptrace_call_wrapper，它的完成两个功能：
//一是调用ptrace_call函数来执行指定函数，执行完后将子进程挂起；
//二是调用ptrace_getregs函数获取所有寄存器的值，主要是为了获取r0即函数的返回值。  
int ptrace_call_wrapper(pid_t target_pid, const char * func_name, void * func_addr, long * parameters, int param_num, struct pt_regs * regs)     
{    
    DEBUG_PRINT("[+] Calling %s in target process.\n", func_name);    
    if (ptrace_call(target_pid, (uintptr_t)func_addr, parameters, param_num, regs) == -1)    
        return -1;    

    if (ptrace_getregs(target_pid, regs) == -1)    
        return -1;    
    DEBUG_PRINT("[+] Target process returned from %s, return value=%llx, pc=%llx \n",     
            func_name, ptrace_retval(regs), ptrace_ip(regs));    
    return 0;    
}    

//远程注入
int inject_remote_process(pid_t target_pid, const char *library_path, const char *function_name, const char *param, size_t param_size)    
{    
    int ret = -1;    
    void *mmap_addr, *dlopen_addr, *dlsym_addr, *dlclose_addr, *dlerror_addr;    
    void *local_handle, *remote_handle, *dlhandle;    
    uint8_t *map_base = 0;    
    uint8_t *dlopen_param1_ptr, *dlsym_param2_ptr, *saved_r0_pc_ptr, *inject_param_ptr, *remote_code_ptr, *local_code_ptr;    

    struct pt_regs regs, original_regs;     
    long parameters[10];    

    DEBUG_PRINT("[+] Injecting process: %d\n", target_pid);    

    //①ATTATCH，指定目标进程，开始调试
    if (ptrace_attach(target_pid) == -1)    
        goto exit;   

    //②GETREGS，获取目标进程的寄存器，保存现场
    if (ptrace_getregs(target_pid, &regs) == -1)    
        goto exit;    

    /* save original registers */    
    memcpy(&original_regs, &regs, sizeof(regs));    

//③通过get_remote_addr函数获取目的进程的mmap函数的地址，以便为libxxx.so分配内存

/*
需要对(void*)mmap进行说明：这是取得inject本身进程的mmap函数的地址，由于mmap函数在libc.so  
库中，为了将libxxx.so加载到目的进程中，就需要使用目的进程的mmap函数，所以需要查找到libc.so库在目的进程的起始地址。
*/
    mmap_addr = get_remote_addr(target_pid, libc_path, (void *)mmap);    
    DEBUG_PRINT("[+] Remote mmap address: %llx\n", mmap_addr);

/* call mmap (null, 0x4000, PROT_READ | PROT_WRITE | PROT_EXEC,
                         MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
匿名申请一块0x4000大小的内存
*/
    parameters[0] = 0;  // addr    
    parameters[1] = 0x4000; // size    
    parameters[2] = PROT_READ | PROT_WRITE | PROT_EXEC;  // prot    
    parameters[3] = MAP_ANONYMOUS | MAP_PRIVATE; // flags    
    parameters[4] = 0; //fd    
    parameters[5] = 0; //offset    

    if (ptrace_call_wrapper(target_pid, "mmap", mmap_addr, parameters, 6, &regs) == -1)    
        goto exit;    

//⑤从寄存器中获取mmap函数的返回值，即申请的内存首地址：
    map_base = ptrace_retval(&regs);  

//⑥依次获取linker中dlopen、dlsym、dlclose、dlerror函数的地址:
    dlopen_addr = get_remote_addr( target_pid, linker_path, (void *)dlopen );    
    dlsym_addr = get_remote_addr( target_pid, linker_path, (void *)dlsym );    
    dlclose_addr = get_remote_addr( target_pid, linker_path, (void *)dlclose );    
    dlerror_addr = get_remote_addr( target_pid, linker_path, (void *)dlerror );    

    DEBUG_PRINT("[+] Get imports: dlopen: %llx, dlsym: %llx, dlclose: %llx, dlerror: %llx\n",    
            dlopen_addr, dlsym_addr, dlclose_addr, dlerror_addr);    

    printf("library path = %s\n", library_path);    
//⑦调用dlopen函数：
/*
①将要注入的so名写入前面mmap出来的内存
②写入dlopen代码
③执行dlopen("libxxx.so", RTLD_NOW ! RTLD_GLOBAL) 
RTLD_NOW之类的参数作用可参考：
http://baike.baidu.com/view/2907309.htm?fr=aladdin 
④取得dlopen的返回值，存放在sohandle变量中
*/
    ptrace_writedata(target_pid, map_base, library_path, strlen(library_path) + 1);  

    parameters[0] = map_base;       
    parameters[1] = RTLD_NOW| RTLD_GLOBAL;     

    if (ptrace_call_wrapper(target_pid, "dlopen", dlopen_addr, parameters, 2, &regs) == -1)    
        goto exit;    

    void * sohandle = ptrace_retval(&regs);    
    if(!sohandle) {
    if (ptrace_call_wrapper(target_pid, "dlerror", dlerror_addr, 0, 0, &regs) == -1)    
        goto exit;    

    uint8_t *errret = ptrace_retval(&regs);  
    uint8_t errbuf[100];
    ptrace_readdata(target_pid, errret, errbuf, 100);
  }

    //⑧调用dlsym函数
/*
等同于hook_entry_addr = (void *)dlsym(sohandle, "hook_entry");
*/ 
#define FUNCTION_NAME_ADDR_OFFSET       0x100    
    ptrace_writedata(target_pid, map_base + FUNCTION_NAME_ADDR_OFFSET, function_name, strlen(function_name) + 1);    
    parameters[0] = sohandle;       
    parameters[1] = map_base + FUNCTION_NAME_ADDR_OFFSET;     

    if (ptrace_call_wrapper(target_pid, "dlsym", dlsym_addr, parameters, 2, &regs) == -1)    
        goto exit;    

    void * hook_entry_addr = ptrace_retval(&regs);    
    DEBUG_PRINT("hook_entry_addr = %p\n", hook_entry_addr);    

//⑨调用hook_entry函数：
#define FUNCTION_PARAM_ADDR_OFFSET      0x200    
    ptrace_writedata(target_pid, map_base + FUNCTION_PARAM_ADDR_OFFSET, param, strlen(param) + 1);    
    parameters[0] = map_base + FUNCTION_PARAM_ADDR_OFFSET;      

    if (ptrace_call_wrapper(target_pid, "hook_entry", hook_entry_addr, parameters, 1, &regs) == -1)    
        goto exit;        

    printf("Press enter to dlclose and detach\n");    
    getchar();    
    parameters[0] = sohandle;       

//⑩调用dlclose关闭lib:
    if (ptrace_call_wrapper(target_pid, "dlclose", dlclose, parameters, 1, &regs) == -1)    
        goto exit;    

    /* restore */    
//⑪恢复现场并退出ptrace:
    ptrace_setregs(target_pid, &original_regs);    
    ptrace_detach(target_pid);    
    ret = 0;    

exit:    
    return ret;    
}    

int main(int argc, char** argv) {    
    pid_t target_pid;    
    target_pid = find_pid_of("system_server");
    if (-1 == target_pid) {  
        printf("Can't find the process\n");  
        return -1;  
    }  
    //target_pid = find_pid_of("/data/test");    
    inject_remote_process(target_pid, "/data/libhello.so", "hook_entry",  "I'm parameter!", strlen("I'm parameter!"));    
    return 0;  
}

Android.mk application.mk

APP_ABI :=arm64-v8a armeabi-v7a

LOCAL_PATH := $(call my-dir)  

include $(CLEAR_VARS)  
LOCAL_MODULE := inject   
LOCAL_SRC_FILES := inject.c   

#shellcode.s  

LOCAL_LDLIBS += -L$(SYSROOT)/usr/lib -llog  

#LOCAL_FORCE_STATIC_EXECUTABLE := true  

include $(BUILD_EXECUTABLE)  

2.inject的测试so

#include <unistd.h>  
#include <stdio.h>  
#include <stdlib.h>  
#include <android/log.h>  
#include <elf.h>  
#include <fcntl.h>  

#define LOG_TAG "DEBUG"  
#define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, fmt, ##args)    

int hook_entry(char * a){  
    LOGD("Hook success, pid = %d\n", getpid());  
    LOGD("Hello %s\n", a);  
    return 0;  
}