[Feature] Expanding InUser or adding InAuthUser in metadata

[xzycn]

Verification Steps

• I have read the documentation and confirmed that this feature is not implemented
• I have searched for the feature request I want to propose in the Issue Tracker and did not find it
• I am a non-Chinese user.

Description

Hi, we see there has a InUser in metadata struct, but sometimes we need know what's password in incoming connection not only username.

Can we get a authuser like below from metadata, thanks.

type AuthUser struct {
	User string
	Pass string
}

[xishang0128]

@xzycn Please check the box completely, otherwise we will close the issue.

[xzycn]

@xishang0128 update.