AMF解码示例

Question

我正在尝试阅读一些flex/amf流量，但缺乏适当的文档/示例使其变得非常困难。

请告诉我以下rtmp/amf3数据包的解码过程：

0x43, 0x00, 0x68, 0xcd, 0x00, 0x01, 0x33, 0x11, 0x00, 0x05, 0x00, 0x40, 0x33, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0x11, 0x0a, 0x81, 0x13, 0x4f, 0x66, 0x6c, 0x65, 0x78, 0x2e, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x69, 0x6e, 0x67, 0x2e, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x73, 0x2e, 0x52, 0x65, 0x6d, 0x6f, 0x74, 0x69, 0x6e, 0x67, 0x4d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x0d, 0x73, 0x6f, 0x75, 0x72, 0x63, 0x65, 0x13, 0x6f, 0x70, 0x65, 0x72, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x0f, 0x68, 0x65, 0x61, 0x64, 0x65, 0x72, 0x73, 0x17, 0x64, 0x65, 0x73, 0x74, 0x69, 0x6e, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x13, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x49, 0x64, 0x11, 0x63, 0x6c, 0x69, 0x65, 0x6e, 0x74, 0x49, 0x64, 0x15, 0x74, 0x69, 0x6d, 0x65, 0x54, 0x6f, 0x4c, 0x69, 0x76, 0x65, 0x13, 0x74, 0x69, 0x6d, 0x65, 0xc3, 0x73, 0x74, 0x61, 0x6d, 0x70, 0x09, 0x62, 0x6f, 0x64, 0x79, 0x01, 0x06, 0x29, 0x6c, 0x69, 0x73, 0x74, 0x41, 0x6c, 0x6c, 0x50, 0x72, 0x61, 0x63, 0x74, 0x69, 0x63, 0x65, 0x47, 0x61, 0x6d, 0x65, 0x73, 0x0a, 0x0b, 0x01, 0x21, 0x44, 0x53, 0x52, 0x65, 0x71, 0x75, 0x65, 0x73, 0x74, 0x54, 0x69, 0x6d, 0x65, 0x6f, 0x75, 0x74, 0x04, 0x3c, 0x15, 0x44, 0x53, 0x45, 0x6e, 0x64, 0x70, 0x6f, 0x69, 0x6e, 0x74, 0x06, 0x11, 0x6d, 0x79, 0x2d, 0x72, 0x74, 0x6d, 0x70, 0x73, 0x09, 0x44, 0x53, 0x49, 0x64, 0x06, 0x49, 0x42, 0x45, 0x32, 0x34, 0x31, 0x32, 0x33, 0x34, 0x2d, 0x31, 0x45, 0x31, 0x39, 0x2d, 0x30, 0x33, 0x43, 0x33, 0x2d, 0x39, 0x30, 0x34, 0x43, 0x2d, 0x32, 0x31, 0x36, 0x33, 0x36, 0x36, 0x30, 0x41, 0x42, 0x34, 0x37, 0x46, 0x01, 0x06, 0x17, 0x67, 0x61, 0x6d, 0x65, 0x53, 0x65, 0xc3, 0x72, 0x76, 0x69, 0x63, 0x65, 0x06, 0x49, 0x31, 0x34, 0x43, 0x30, 0x46, 0x42, 0x38, 0x30, 0x2d, 0x46, 0x37, 0x43, 0x34, 0x2d, 0x42, 0x42, 0x34, 0x42, 0x2d, 0x31, 0x46, 0x32, 0x34, 0x2d, 0x34, 0x39, 0x36, 0x32, 0x38, 0x30, 0x42, 0x38, 0x39, 0x33, 0x42, 0x38, 0x01, 0x04, 0x00, 0x04, 0x00, 0x09, 0x01, 0x01

我的尝试是：

0x43 - 0100 0011 : 01 - type 1= rtmp报头将为7个字节。流ID - 3，将在此单个字节中。

还设法通过移位UTF 1位来读取以下内容，以获得长度：

0x4f: flex.messaging.messages.RemotingMessage

0x0d:源

0x13:操作

0x0f:标头

0x17:目的地

0x13: messageId

0x11: clientId

0x15: timeToLive

我的猜测到此结束，"time“/ "stamp”似乎不起作用。当然，我不能理解所有其他字节是如何编码的(对象/数组等)；

Answer 1

使用Charles解析AMF！http://www.charlesproxy.com/documentation/additional/amf/

Answer 2

0x43, 0x00, 0x68, 0xcd, 0x00, 0x01, 0x33, 0x11

1byte+7bytes RTMP报头数据[0]

0x00, 0x05, 0x00, 0x40, 0x33, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05

Flex魔术字节，与调用版本、id等有关的内容

0x11

AMF3数据的开始

0x0a.....

AMF3对象和常规AMF3编码[1]

注意:关于RTMP，它将AMF数据分成最小的128个字节，后面跟着一个标题字节(不是AMF的一部分)，例如上例中的0xc3。

Answer 3

我会从阅读开始

AMF0

AMF3

在Wikipedia上可以找到更多的例子。

然后是你可能不需要的RTMP Specification。

接下来，您可以查看FluorineFX的源代码。这让我开始了解一些事情。Sources FluorineFX。我所做的是在FluorineFX源代码中设置断点，然后从Flex应用程序进行调用。然后我可以一步一步了解FluorineFX源代码(在我旁边是AMF规范)。

规范很难读懂，但它们确实是解析字节所需的全部内容。

也许你也可以看看this JavaScript AMF project。