UserMgr plug-in

Author: hgerstung (talk, contrib)

Links

UserMgr.zip (49 KB)

Find the original plugin of the author (15.8.2006) at http://www.meinberg.de/download/utils/UserMgr.zip

UserMgr thread on NSIS Discussion forum

Description

I needed to create a user account in my installer, running a service with restricted rights is something we all should try to do whenever possible.

In order to get this functionality, I used the UserInfo plugin as a starter and created a number of functions dealing with user accounts, privileges and groups.

"'Please note: This plugin and its functions are only useful for Windows NT/2K/XP target systems."'
You should check the type of system in your installer script before trying to call one of the functions of this DLL. I did not test what happens when someone tries to use UserMgr on a Win95/Win98 system.

As I am currently the only one using this, I consider it in beta state and appreciate any comments and feedback, e.g. "Yes, it runs on Winxyz" or "No, no chance on Win87 etc. etc.).

You can reach me via PM, my forum account is hgerstung, so do not hesitate to contact me if you are experiencing difficulties.

Known Issues

Windows 9x support

Untested on Windows 9x; structure is different, so probably not going to work.

Any help in resolving these issues (submitting a patch, etc) is appreciated.

Plugin Command Reference

Here's a list of functions the DLL exports including the necessary parameters.

UserMgr::CreateAccount "USERID PASSWORD COMMENT"

creates a new user account, returns status string

UserMgr::CreateAccountEx "USERID PASSWORD COMMENT FULLNAME USERCOMMENT FLAGS"

creates a new user account, including the Fullname (Shown in the Welcome screen), returns status string

where "FLAGS" can be one of the following:

UF_ACCOUNTDISABLE

The user's account is disabled.

UF_PASSWD_NOTREQD

No password is required.

UF_PASSWD_CANT_CHANGE

The user cannot change the password.

UF_DONT_EXPIRE_PASSWD

The password will never expire on the account.

UserMgr::GetCurrentUserName

returns the username of the currently logged in user

UserMgr::BuiltAccountEnv "USERID PASSWORD"

builds the User environment of the user (Registry hive, Documents and settings etc.), returns status string

UserMgr::RegLoadUserHive "USERID"

loads the User Registry hive in HKEY_USERS\{USERID}, returns status string

UserMgr::RegUnLoadUserHive "USERID"

unloads the User Registry hive, returns status string

UserMgr::DeleteAccount "USERID"

deletes a user account, returns status string

UserMgr::AddToGroup "USERID GROUPID"

adds a user to a group, returns status string

UserMgr::RemoveFromGroup "USERID GROUPID"

removes group membership from a user, returns status string

UserMgr::IsMemberOfGroup "USERID GROUPID"

returns "TRUE" if the user is a member of the specified group, else returns "FALSE"

UserMgr::AddPrivilege "USERID PRIVILEGE"

adds a privilege to the user account, returns status string. You can find a list of privileges below.

UserMgr::RemovePrivilege "USERID PRIVILEGE"

removes a privilege from an account, returns status string. You can find a list of privileges below.

UserMgr::CreateGroup "GROUPID COMMENT"

creates a new user group, returns status string

UserMgr::DeleteGroup "GROUPID"

deletes a user group, returns status string

UserMgr::GetUserInfo "USERID FIELD"

returns a specific information for the given user-ID

where "FIELD" can be one of the following:

EXISTS

returns "OK", if the user exists on the system, otherwise an error is returned (string "ERROR xxxx")

NAME

returns the user name

FULLNAME

returns the full user name (e.g. firstname surname)

HOMEDIR

returns the path to the users home directory

COMMENT

returns a comment stored for the user

UserMgr::SetUserInfo "USERID FIELD VALUE"

sets a specific information for the given user-ID

where "FIELD" can be one of the following:

NAME

sets the user name

FULLNAME

sets the full user name (e.g. firstname surname)

HOMEDIR

sets the path to the users home directory

COMMENT

sets a comment stored for the user

PASSWD_NEVER_EXPIRES ["YES"/"NO"]

enables/disables password expiration

PASSWORD

sets the user password (Admin rights required)

UserMgr::ChangeUserPassword "USERID OLDPASSWORD NEWPASSWORD"

changes the user password (Admin rights not required)

UserMgr::GetLocalizedStdAccountName "STDACCOUNTSID"

returns the localized Standard Account name

(e.g. "NT AUTHORITY\SYSTEM" for "S-1-5-18" on a English system

and "NT-AUTORITÄT\NETZWERKDIENST" for "S-1-5-20" on a German system)

The most often used SID's are defined in the included SpecialGroupsSIDs.nsh

UserMgr::SetRegKeyAccess "USERID ROOTKEY REGKEY ACCESSMASK"

adds/sets/revokes/denies access rights for registry keys

where "ROOTKEY" can be one of these: HKLM, HKU, HKCU, HKCR

where "ACCESSMASK" starts with a '+' to grant rights, "-" to deny rights, "=" to set rights, afterwards the rights can be listed: 'r' for read access, 'w' for write access, 'x' for execute access, 'a' for full access.

BEWARE

If ACCESSMASK is empty, all of the the users access rights will be removed! This is used to delete an access list entry from a registry key.

example:

 UserMgr::SetRegKeyAccess "myuser" "HKLM" "SYSTEM\CurrentControlSet\Services\Blabla" "=a"

grants full access for "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Blabla" to user "myuser"

Return value

"'A status string can look like this:"'

"OK"

Function has been completed successfully

"ERROR xxxx"

An error occurred. Please see MSDN or the LMERR.H file (comes with Visual Studio) to find out about possible error codes. You may also find the Network Management page on MSDN to be useful.

Example

Here is a short example of how to use the functions in an Installer script:

Name "UserMgr.dll Sample Installation Script"
 
OutFile "usermgr-sample.exe"
 
#
# Be careful when using these functions, especially the "Remove" and "Delete"
# commands!!!
#
 
Function .onInit
        # the plugins dir is automatically deleted when the installer exits
        InitPluginsDir
 
	UserMgr::CreateAccount "myuser" "mypassword" "A test user created by the UserMgr plugin"
	Pop $0
        MessageBox MB_OK "CreateUser Result : $0"
 
	UserMgr::AddToGroup  "myuser" "Administrators"
	Pop $0
        MessageBox MB_OK "AddToGroup Result : $0"
 
	UserMgr::SetRegKeyAccess "myuser" "HKLM" "SYSTEM\CurrentControlSet\Services\EventLog\Application\NTP" "=a"
	Pop $0
        MessageBox MB_OK "GrantAccess Result : $0"
 
	UserMgr::SetRegKeyAccess "myuser" "HKLM" "SYSTEM\CurrentControlSet\Services\EventLog\Application\NTP" "=r"
	Pop $0
        MessageBox MB_OK "RevokeWriteAccess Result : $0"
 
	UserMgr::SetRegKeyAccess "myuser" "HKLM" "SYSTEM\CurrentControlSet\Services\EventLog\Application\NTP" ""
	Pop $0
        MessageBox MB_OK "RevokeAccess Result : $0"
 
	UserMgr::DeleteAccount "myuser"
	Pop $0
        MessageBox MB_OK "DeleteUser Result: $0"
 
        #######################################################################
 
	UserMgr::CreateAccountEx "myuserA" "mypassword" "A test user created by the UserMgr plugin" "My User A" "A test user created by the UserMgr plugin" "UF_PASSWD_NOTREQD|UF_DONT_EXPIRE_PASSWD"
	Pop $0
        MessageBox MB_OK "CreateUser Result : $0"
 
	UserMgr::BuiltAccountEnv "myuserA" "mypassword"
	Pop $0
        MessageBox MB_OK "BuiltAccountEnv Result : $0"
 
	UserMgr::RegLoadUserHive "myuserA"
	Pop $0
        MessageBox MB_OK "RegLoadUserHive Result : $0"
 
        WriteRegStr HKEY_USERS "myuserA\Software\My Company\My Software" "String Value" "dead beef"
 
	UserMgr::RegUnLoadUserHive "myuserA"
	Pop $0
        MessageBox MB_OK "RegUnLoadUserHive Result : $0"
 
	UserMgr::ChangeUserPassword "myuserA" "mypassword" "mypasswordb"
	Pop $0
        MessageBox MB_OK "ChangeUserPassword Result : $0"
 
	UserMgr::SetUserInfo "myuserA" "PASSWORD" "mypasswordc"
	Pop $0
        MessageBox MB_OK "SetUserInfo PASSWORD Result : $0"
 
	UserMgr::DeleteAccount "myuserA"
	Pop $0
        MessageBox MB_OK "DeleteUser Result: $0"
 
 
FunctionEnd
 
Section
SectionEnd

Incomplete List of Account Privileges

This list was taken from a web site and surely is not complete. You may have to ask Google or whoever to find out about certain privileges.

"'Side note:"' On my machine I needed to "grant" a user the SeDenyInteractiveLogonRight to deny the account to log in interactively - although it did not possess the SeInteractiveLogonRight privilege and was not a a member of any group. This is the same with SeDenyBatchLogonRight, SeDenyNetworkLogonRight and SeDenyServiceLogonRight. You can clearly see that the "i" in Micro$oft stands for "inconsistency" :-)

SeAssignPrimaryTokenPrivilege

Replace a process level token

SeAuditPrivilege

Generate security audits

SeBackupPrivilege

Back up files and directories

SeBatchLogonRight

Log on as a batch job

SeChangeNotifyPrivilege

Bypass traverse checking

SeCreatePagefilePrivilege

Create a pagefile

SeCreatePermanentPrivilege

Create permanent shared objects

SeCreateTokenPrivilege

Create a token object

SeDebugPrivilege

Debug programs

SeIncreaseBasePriorityPrivilege

Increase scheduling priority

SeIncreaseQuotaPrivilege

Increase quotas

SeInteractiveLogonRight

Log on locally

SeLoadDriverPrivilege

Load and unload device drivers

SeLockMemoryPrivilege

Lock pages in memory

SeMachineAccountPrivilege

Add workstations to domain

SeNetworkLogonRight

Access this computer from the network

SeProfileSingleProcessPrivilege

Profile single process

SeRemoteShutdownPrivilege

Force shutdown from a remote system

SeRestorePrivilege

Restore files and directories

SeSecurityPrivilege

Manage auditing and security log

SeServiceLogonRight

Log on as a service

SeShutdownPrivilege

Shut down the system

SeSystemEnvironmentPrivilege

Modify firmware environment values

SeSystemProfilePrivilege

Profile system performance

SeSystemtimePrivilege

Change the system time

SeTakeOwnershipPrivilege

Take ownership of files or other objects

SeTcbPrivilege

Act as part of the operating system

SeUnsolicitedInputPrivilege

Read unsolicited input from a terminal device

Changes

JPR 01 Jan 2008:

• NetLocalGroupAddMembers used instead of NetGroupAddUser in the AddToGroup function to make it work. (Thanks to the article of CancerFace (http://nsis.sourceforge.net/User_Management_using_API_calls))
• PASSWORD added as possible FIELD for the SetUserInfo function. With this field the user password can be changed
• The function ChangeUserPassword is added to be able to change a user password
• The function CreateAccountEx is added to be able to add a fullname of a user (Shown in the Welcome Screen) and add flags to the user (Password never expires etc.)
• The function BuiltAccountEnv is added. This function creates the User Environment (Documents and settings\{User} folder, User Registry Hive etc. to be able to do something there without the need to login as the new created user first
• The function RegLoadUserHive is added. This function loads the User Registry hive in HKEY_USERS\{USERID} to be able to add keys and values to the HKEY_CURRENT_USER of this user
• The function RegUnLoadUserHive is added. This function unloads the User Registry hive

JPR 14 Jan 2008:

• Fixed a small bug in GetUserInfo function
• Fixed 2 small bugs in SetUserInfo function
• Added GetCurrentUserName function
• Added GetLocalizedStdAccountName function
• Added IsMemberOfGroup function

JPR 15 Jan 2008:

• Fixed a small bug in RegLoadUserHive function