离线加载原理，以及拦截任意Scheme

今天看到阿里的mpass上有离线加载H5，简单研究了这里用WebKit的WKURLSchemeHandler那套，非NSURLProtocol，间接的跨域。其实拿来做逆向破解也不是不可以
主要code:

- (void)viewDidLoad {
    [super viewDidLoad];
    self.webHandler = [[MySchemeHandler alloc] init];
    WKWebViewConfiguration *webViewConfiguration = [[WKWebViewConfiguration alloc] init];
    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"myScheme://myScheme.test.cn/index.html"] cachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData timeoutInterval:10.0f];
    [webViewConfiguration setURLSchemeHandler:self.webHandler forURLScheme:@"myScheme"];
    [webViewConfiguration setURLSchemeHandler:self.webHandler forURLScheme:@"http"];
    self.webView = [[WKWebView alloc] initWithFrame:self.view.frame configuration:webViewConfiguration];
    [self.webView loadRequest:request];
    [self.view addSubview:self.webView];
}

这里支持http、https的拦截
MySchemeHandler.m的主要代码：

- (void)webView:(nonnull WKWebView *)webView startURLSchemeTask:(nonnull id<WKURLSchemeTask>)urlSchemeTask {

    NSLog(@"拦截到请求的URL：%@", urlSchemeTask.request.URL);
    NSString *localFileName = [urlSchemeTask.request.URL lastPathComponent];
    
    
    if([localFileName isEqualToString:@"getIp.php"]){
        //拦截到的 http的XMLHttpRequest的异步请求
        NSURLSessionDataTask *session = [[NSURLSession sharedSession] dataTaskWithRequest:urlSchemeTask.request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
            
            [urlSchemeTask didReceiveResponse:response];
            [urlSchemeTask didReceiveData:data];
            [urlSchemeTask didFinish];
        }];
        [session resume];
        return;
    }
    NSString *path = [[NSBundle mainBundle] pathForResource:@"test" ofType:@"html"];
    NSString *html = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:NULL];
    NSData *data = [html dataUsingEncoding:4];
    NSString *fileMIME = [self getMIMETypeWithCAPIAtFilePath:path];
    NSDictionary *responseHeader = @{
                                     @"Content-type":fileMIME,
                                     @"Content-length":[NSString stringWithFormat:@"%lu",(unsigned long)[data length]]
                                     };
    NSHTTPURLResponse *response = [[NSHTTPURLResponse alloc] initWithURL:[NSURL URLWithString:[NSString stringWithFormat:@"%@%@", @"myScheme://myScheme.test.cn/", @"index.html"]] statusCode:200 HTTPVersion:@"HTTP/1.1" headerFields:responseHeader];
    [urlSchemeTask didReceiveResponse:response];
    [urlSchemeTask didReceiveData:data];
    [urlSchemeTask didFinish];
}

实现拦截http,https的拦截的主要代码：

CHDeclareClass(WKWebView)
CHClassMethod1(BOOL, WKWebView, handlesURLScheme, NSString *, urlScheme) {
    
    if([urlScheme isEqualToString:@"http"] || [urlScheme isEqualToString:@"https"]) {
        
        return NO;
    }
    
    return CHSuper1(WKWebView, handlesURLScheme, urlScheme);
}
__attribute__((constructor())) static void entry3() {
    
//   写到 XLWebViewConfiguration load 也可
    CHLoadLateClass(WKWebView);
    CHClassHook1(WKWebView, handlesURLScheme);
}

代码demo:https://github.com/LoveSVN/MySchemeHandler.git
最后的效果图：

WechatIMG6.jpeg WechatIMG3.png WechatIMG4.png WechatIMG5.png