1. IPMI 2.0 spec P619 附录G

IPMI 2.0 Spec学习 - 球球小世界 - 博客园 (cnblogs.com)
IPMI Specification, V2.0, Rev. 1.1: Document (intel.cn)
BMC(基板管理控制器)_360百科 (so.com)
IPMI_百度百科 (baidu.com)

附录G规范了目录格式

1. Unless otherwise specified, unauthenticated, session-less interfaces, such as the System Interface and IPMB, can support any IPMI command.    # 定义了BMC支持的接口
2. The privilege level requirements for OEM commands (NetFn=OEM, OEM/Group) is specified by the OEM identified by the corresponding manufacturer ID.  # 谁做的BMC就显示谁的ID
3. Note that the Send Message and Master Write-Read commands are not available at the User privilege level, with the exception of using a Send Message command to deliver a message to the System Interface. This is because these commands enable unfiltered access the IPMB, ICMB, private management busses, and PCI Management Bus. This would potentially allow someone to use those commands to send commands to other controllers or write to non-intelligent devices on those busses. As a consequence, a User is only able to read FRU and sensors directly managed by the BMC. In addition, FRU must be accessed via the Read 
FRU command and not Master Write-Read.
4. The Send Message command can be used to deliver a message to the System Interface at User privilege level. It is up to the system software to determine the privilege level and place any additional restrictions on messages received via the Receive Message Queue. This can be accomplished by using the session handle associated with the message and the Get Session Info command to look up the privilege level that the user is operating at. Software can also check the limits for the channel and the user by using information from the Get Channel Access and Get User Access commands to determine whether a given user has sufficient privilege to deliver a particular command to system software.
# 3/4 定义了不同命令在不同使用场景下的区别，
5. Unless otherwise specified, the listed IPMI commands, if supported, must be accessible via LUN 00  # IPMI命令支持的LUN是00B （第7章）
a User is only able to read FRU and sensors directly managed by the BMC
后面表格：权限标记

Key for Command Privilege Levels Table:
b = command only generated by BMC, can be sent prior to a session being established
b1 = command only generated by BMC, can only be delivered to a session-less channel, or a channel that
has an active session
b2 = command only generated by BMC, can be sent to a serial channel when serial port sharing is used and
activating the SOL payload causes the serial session to be terminated.
b3 = command only generated by BMC, can only be delivered to a session-less channel.
p = works at any privilege level, can be sent prior to a session being established
s = command executable via system interface only
X = supported at given privilege level or higher
I = command executable from local interfaces only (e.g. IPMB, SMBus, PCI Mgmt. bus or System
Interface)
C = Callback privilege
U = User Privilege level
O = Operator Privilege level
A = Administrator Privilege level
App = Application Network Function Code
S/E = Sensor/Event Network Function Code

• = Reserved/unassigned, or OEM specified

NetFn有七类，P67
00/02/04/06/08/0A/0C request
01/03/05/07/09/0B/0D response
其中06为App

P619， 每条命令对应的CMD是唯一的，
C/U/O/A为对权限的要求
X：只能User或更高的权限才可以执行。
C 权限最低，A最高
p3: p 的权限与 P623 第3条说明结合去理解使用范围

1. This command is sent using the Broadcast format on IPMB. See command description for details.
2. A User can use a Send Message command to deliver a message to system software, but 
Operator privilege is required to use it to access other channels.
3. Command only applies to authenticated channels.
4. This is effectively a no-op if the user has a maximum privilege limit of User since the command 
could not be used to change the operating privilege level to a higher value.
5. A session operating at Callback, User, or Operator can only use this command to terminate their 
own session. An Administrator or system software can use the command to terminate any 
session.
6. There is a bit in this command that can only be set at Administrator privilege level.
7. Command available for all levels except for User level
8. See [ICMB] specification for command specifications.
9. The Suspend/Resume Payload Encryption command may be overridden by a configuration 
option for the particular payload type that forces encryption to be used. In this case, an Admin 
level command would typically be required to change the configuration.
10. The configuration parameters for a given payload type determine the privilege level required to 
activate / deactivate the payload

每条命令都有权限要求，并非所有命令都可以在带内/带外下发