向海康发起控制命令后回复状态码400（SIP/2.0 400 Bad Request）如何解决。感谢诸君(╥╯^╰╥)
这是设备控制流程图（个人怀疑第三步骤出现问题，如何在代码中修改message中的内容）
MESSAGE sip:37030000001320000023@192.168.44.108:5060 SIP/2.0
Via: SIP/2.0/UDP 192.168.7.173:5060;rport;branch=z9hG4bK2340348034
From: <sip:34020000002000000001@192.168.44.10:5060>;tag=542424917
To: <sip:37030000001320000023@192.168.44.108:5060>
Call-ID: 2165577845
CSeq: 20 MESSAGE
Content-Type: application/MANSCDP+xml
Max-Forwards: 70
User-Agent: eXosip/4.0.0
Date: 2022-08-22T09:40:56.359
Content-Length: 170
<?xml version="1.0"?>
<Control>
<CmdType>DeviceControl</CmdType>
<SN>4</SN>
<DeviceID>37030000001320000023</DeviceID>
<PTZCmd>A50F0000000000B4</PTZCmd>
</Control>
SIP/2.0 200 OK
Via: SIP/2.0/UDP 192.168.7.173:5060;rport=5060;branch=z9hG4bK2340348034;received=192.168.44.10
From: <sip:34020000002000000001@192.168.44.10:5060>;tag=542424917
To: <sip:37030000001320000023@192.168.44.108:5060>;tag=737818244
Call-ID: 2165577845
CSeq: 20 MESSAGE
User-Agent: Sent IC6
Content-Length: 0
/*个人推测这里出现了问题*/
MESSAGE sip:34020000002000000001@192.168.44.10:5060 SIP/2.0 //这里的sip:应该接目的设备编码37030000001320000023
Via: SIP/2.0/UDP 192.168.44.108:5060;rport;branch=z9hG4bK595070064
From: <sip:37030000001320000023@192.168.44.10:5060>;tag=2038601463 //这里from:<sip:后接源设备编码34020000002000000001
To: <sip:34020000002000000001@192.168.44.10:5060> //to接目的设备编码37030000001320000023
Call-ID: 1917360025
CSeq: 20 MESSAGE
Content-Type: Application/MANSCDP+xml
Max-Forwards: 70
User-Agent: Sent IC6
Content-Length: 151
<?xml version="1.0"?>
<Response>
<CmdType>DeviceControl</CmdType>
<SN>4</SN>
<DeviceID>37030000001320000023</DeviceID>
<Result>OK</Result>
</Response>
SIP/2.0 400 Bad Request //这里出现状态码400
Via: SIP/2.0/UDP 192.168.44.108:5060;rport=5060;branch=z9hG4bK595070064
From: <sip:37030000001320000023@192.168.44.10:5060>;tag=2038601463
To: <sip:34020000002000000001@192.168.44.10:5060>;tag=1280943331
Call-ID: 1917360025
CSeq: 20 MESSAGE
User-Agent: eXosip/4.0.0
Content-Length: 0
这是控制第三步骤的信令格式
应该对gb28181代码中的哪块的地方进行改动，才能让message中的内容进行修改。
