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发信人: zzn (爱你到内伤), 信区: Network
标题: mms协议英文资料(17)
发信站: 哈工大紫丁香 (2003年08月23日10:54:57 星期六), 站内信件

32 To Server
Prefix 1 4 byte field – CommandLevel
Prefix 2 4 byte field – ??
Then the rest of dump data (structure not yet defined)
This command is interesting, it indicates that what follows (in its extra data
fields) is a data dump of your local computer name and details. This includes
things like your logon name, what codecs you have, your computer processor
and OS. All sorts of interesting things you may not want the server to know.
Please read the section ‘Your personal data security flaw’
33 To Server
This command is the media stream MBR selector.
No prefix data is used.
Structure as below:
01 00 00 00 - stream structure count value (e.g. only 1 here)
followed by a stream selection structure (6 bytes long):
ff ff - flags
01 00 – stream ID number
00 00 – stream state action (00 = switch it on, 02 means off)
Then other stream selection structures follow for all other streams if any.
The data ends with an 8 byte structure ending as below:
[00 00]
[00 20 ac 40]
[02 00]
where:
[00 00] shows 0x61 0x00 (on the first 33 command sent) or 0xff 0xff for ASF
files, and with no ending data for WMV files. It is not yet understood what
all this means.
[00 20 AC 40] looks like a 32 bit float value which would equal 3600 in
decimal. Or it could be a ‘real’ 6 byte value (now out of date and not used
in programming). In which case the preceding [00 00] would be part of the
value.
Then finally ending with [02 00]. Showing the ‘PacketIDType’ value for
header type streams.
This data is not yet fully defined.
Notes:
‘flags’ is nearly always set to FF FF, but it has been seen that flags can
change state to 02 00. This flag state has only been seen after a stream
re-negotiation after an initial MBR selected rate failed.
An example is shown below:
stream selection structure (6 bytes long):
02 00 - flags, could show an action like ‘toggle’ state.
02 00 – stream ID ??
01 00 – stream state action – could mean turn it off.??
We need to investigate this further.
The ending 8 byte structure shows all FF values in this case.
--
在这里倾听夜暗的歌声/冥冥中谁奏响沉寂百年的古琴/我又看见夏日里美丽的黄昏/
白天奔忙于生活的人/傍晚就三三两两走到一起：/是南方这样的温暖时常发生

路草长满街道/幸与不幸从不同的着落点退出/他们错过记忆里的某件事/
仿佛一只只岩鹰/方向改变了身体仍在憧憬中/越过一座座灰色的城市

※ 来源:·哈工大紫丁香 bbs.hit.edu.cn·[FROM: 202.118.243.49]

Network 版 (精华区)