android - 是否可以在改造库中添加网络拦截器来加密和解密数据有效负载

Question

我的应用程序通过 https 与服务器通信，但为​​了提供额外的安全性，我被告知要加密数据负载，因为它包含敏感数据。由于有很多 Web 服务方法，我正在寻找一种解决方案，可以在公共(public)位置加密请求并解密响应，而不是在我使用的所有类上执行加密/解密并节省大量编码。

经过一番研究，我发现网络拦截器可以用来重写请求/响应。

这是一个好的做法吗？如果没有请解释一下

您能否展示一些重写请求/响应正文的示例。

Answer 1

 private static final Interceptor PARAMS_INTERCEPTOR = new Interceptor() {
    @Override
    public Response intercept(Chain chain) throws IOException {
        Request original = chain.request();
        if (original.body() instanceof FormBody) {
            TempFormBodyBuilder.Builder newFormBody = new TempFormBodyBuilder.Builder();
            FormBody oldFormBody = (FormBody) original.body();
            for (int i = 0; i < oldFormBody.size(); i++) {
                final String encodedName = oldFormBody.encodedName(i);
                String encodedValue = oldFormBody.encodedValue(i);
                if (encodedName.equals("info")) {
                    final String dInfo = URLDecoder.decode(encodedValue, "UTF-8");
                    LogUtil.i(TAG, "info need to be encode : " + dInfo);
                    encodedValue = encodeInfo(dInfo);
                    newFormBody.addEncoded(encodedName, encodedValue);
                } else {
                    newFormBody.addAlEncoded(encodedName, encodedValue);
                }
            }
            final TempFormBodyBuilder builder = newFormBody.build();
            requestBuilder.method(original.method(), builder);
            requestBuilder.header("Content-Length", builder.contentLength() + "");
            final Request request = requestBuilder.build();
            Buffer requestBuffer = new Buffer();
            if (request.body() != null) {
                request.body().writeTo(requestBuffer);
            }
            LogUtil.i(TAG, request.url() + (request.body() != null ? "?" + _parseParams(request.body(), requestBuffer) : ""));
            return chain.proceed(request);
        }
    }
};

private final Interceptor DECODE_INTERCEPTOR = new Interceptor() {
    @Override
    public Response intercept(Chain chain) throws IOException {
        final Response response = chain.proceed(chain.request());

        String type = chain.request().header("TYPE");
        String encryption = chain.request().header("encryption");
        Request request = chain.request()
                .newBuilder()
                .headers(chain.request()
                        .headers()
                        .newBuilder()
                        .removeAll("encryption")
                        .build())
                .build();
        if (encryption) {
            Response originalResponse = chain.proceed(request);
            ResponseBody body = originalResponse.body();
            String result = body.string();
            try {
                result = DES.decode(result, key);
            } catch (Exception e) {
                LogUtil.log(e);
                RxBus.getInstance().postEvent(new AuthException(e, AuthException.MORE_PHONES_LOGIN_CODE));
                throw new AuthException(e, AuthException.MORE_PHONES_LOGIN_CODE);
            }
            return originalResponse.newBuilder().body(ResponseBody.create(MediaType.parse("application/json"), result))
                    .build();
        } else {
            return response;
        }
    }
};

    private Manager(Cache cache) {
    final OkHttpClient.Builder builder = new OkHttpClient.Builder().
            retryOnConnectionFailure(true).
            addNetworkInterceptor(PARAMS_INTERCEPTOR).
            addInterceptor(DECODE_INTERCEPTOR).
            addInterceptor(LOGGING_INTERCEPTOR).
            connectTimeout(TIMEOUT_VALUE, TimeUnit.SECONDS).
            readTimeout(TIMEOUT_VALUE, TimeUnit.SECONDS).
            writeTimeout(TIMEOUT_VALUE, TimeUnit.SECONDS);
    if (cache != null) {
        builder.cache(cache);
    }
    this.mOkHttpClient = builder.build();

}