越獄后會(huì)自動(dòng)安裝cydia，所以我們 可以從這方面入手；也可以借助權(quán)限問(wèn)題分蓖，去讀取應(yīng)用的列表；還可以去讀環(huán)境變量尔许，不越獄的機(jī)器應(yīng)該是讀取不到任何內(nèi)容的么鹤。
下面我們一個(gè)一個(gè)方法來(lái)講：

• 判定常見(jiàn)的越獄文件

/Applications/Cydia.app        
/Library/MobileSubstrate/MobileSubstrate.dylib        
/bin/bash       
/usr/sbin/sshd        
/etc/apt   

這個(gè)表可以盡可能的列出來(lái)，然后判定是否存在味廊，只要有存在的就可以認(rèn)為機(jī)器是越獄了蒸甜。

 #define ARRAY_SIZE(a) sizeof(a)/sizeof(a[0])    
      const char* jailbreak_tool_pathes[] = {    
      "/Applications/Cydia.app",    
      "/Library/MobileSubstrate/MobileSubstrate.dylib",    
      "/bin/bash",    
      "/usr/sbin/sshd",    
      "/etc/apt"    
};   

- (BOOL)isJailBreak    
{    
    for (int i=0; i<ARRAY_SIZE(jailbreak_tool_pathes); i++) {    
        if ([[NSFileManager defaultManager] fileExistsAtPath:[NSString stringWithUTF8String:jailbreak_tool_pathes[i]]]) {    
            NSLog(@"The device is jail broken!");    
            return YES;    
        }    
    }    
    NSLog(@"The device is NOT jail broken!");    
    return NO;    
}

• 判斷cydia的URL scheme，URL scheme是可以用來(lái)在應(yīng)用中呼出另一個(gè)應(yīng)用余佛，是一個(gè)資源的路徑柠新，這個(gè)方法也就是在判定是否存在cydia這個(gè)應(yīng)用。

- (BOOL)isJailBreak    
{    
    if ([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:@"cydia://"]]) {    
        NSLog(@"The device is jail broken!");    
        return YES;    
    }    
    NSLog(@"The device is NOT jail broken!");    
    return NO;    
} 

• 讀取系統(tǒng)所有應(yīng)用的名稱(chēng)衙熔，這個(gè)是利用不越獄的機(jī)器沒(méi)有這個(gè)權(quán)限來(lái)判定的登颓。

#define USER_APP_PATH  @"/User/Applications/"    
- (BOOL)isJailBreak    
{    
    if ([[NSFileManager defaultManager] fileExistsAtPath:USER_APP_PATH]) {    
        NSLog(@"The device is jail broken!");    
        NSArray *applist = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:USER_APP_PATH error:nil];    
        NSLog(@"applist = %@", applist);    
        return YES;    
    }    
    NSLog(@"The device is NOT jail broken!");    
    return NO;    
} 

• 使用stat方法來(lái)判定cydia是否存在
  這個(gè)方法本身思路還是通過(guò)判定cydia應(yīng)用，但方法是用的stat函數(shù)红氯，同時(shí)會(huì)判定是否有注入動(dòng)態(tài)庫(kù)框咙。

#define CYDIA_APP_PATH  "/Applications/Cydia.app"    
int checkInject()    
{    
    int ret;    
    Dl_info dylib_info;    
    int (*func_stat)(const char*, struct stat*) = stat;    
        
    if ((ret = dladdr(func_stat, &dylib_info)) && strncmp(dylib_info.dli_fname, dylib_name, strlen(dylib_name))) {    
        return 0;    
    }    
    return 1;    
}    
    
int checkCydia()    
{    
    // first ,check whether library is inject    
    struct stat stat_info;    
        
    if (!checkInject()) {    
        if (0 == stat(CYDIA_APP_PATH, &stat_info)) {    
            return 1;    
        }    
    } else {    
        return 1;    
    }    
    return 0;    
}    
    
- (BOOL)isJailBreak    
{    
    if (checkCydia()) {    
        NSLog(@"The device is jail broken!");    
        return YES;    
    }    
    NSLog(@"The device is NOT jail broken!");    
    return NO;    
} 

• 讀取環(huán)境變量
  這個(gè)DYLD_INSERT_LIBRARIES環(huán)境變量，在非越獄的機(jī)器上應(yīng)該是空痢甘，越獄的機(jī)器上基本都會(huì)有Library/MobileSubstrate/MobileSubstrate.dylib

char* printEnv(void)    
{    
    charchar *env = getenv("DYLD_INSERT_LIBRARIES");    
    NSLog(@"%s", env);    
    return env;    
}    
    
- (BOOL)isJailBreak    
{    
    if (printEnv()) {    
        NSLog(@"The device is jail broken!");    
        return YES;    
    }    
    NSLog(@"The device is NOT jail broken!");    
    return NO;    
}