API to get getting sessionid from server+username...? (might be OT?)

[Guest Thomas Eg Jørgensen]

Hi,

 

I've been searching for at better place to ask this question, but i

wasn't able to find any:-( If you have a better place for this question,

please let me know...

 

Anyhow, the question is related to developing custom terminal services

administration application...

 

I need to remote control a specific user(defined by the server+username)

in my software. To be able to remote control a specific user i must know

the sessionid of the user. However, the API in windows does not allow me

to query a server for a single username, i must enumerate ALL users and

thereafter compare EACH enumerated user to see if this user has the

correct username....

 

First i must enumerate all sessions on the specific server with:

BOOL WTSEnumerateSessions(

__in HANDLE hServer,

__in DWORD Reserved,

__in DWORD Version,

__out PWTS_SESSION_INFO* ppSessionInfo,

__out DWORD* pCount

);

[ http://msdn2.microsoft.com/en-us/library/aa383833(VS.85).aspx ]

 

....then i must loop all the users(about 200 per server) and query each

of them to verify the username with:

BOOL WTSQuerySessionInformation(

__in HANDLE hServer,

__in DWORD SessionId,

__in WTS_INFO_CLASS WTSInfoClass,

__out LPTSTR* ppBuffer,

__out DWORD* pBytesReturned

);

[ http://msdn2.microsoft.com/en-us/library/aa383838(VS.85).aspx ]

 

This can't be right, can it? the above procedure is, ofcourse, very

slow. About 1 sec to find a random user on a server with about 200

active sessions...and that is just to find the correct sessionid!

 

Here is snippet from my application(Pascal language):

 

//Open the serverhandle for the server in question...

ServerHandle=WTSOpenServerW(PWideChar(ServerName));

try

//Enumerate all users on the server...

if WTSEnumerateSessionsW(ServerHandle,0,1,SessionInfo,nCount) then

begin

//Set the the "CurrentSessionInformation"-pointer to the first

pointer returned by the enumeration...

CurrSessionInfo := SessionInfo;

//Loop as many times as nCount....one for each session...

for a:=1 to nCount do

begin

//Query the session to get the username...

if

WTSQuerySessionInformationW(ServerHandle,CurrSessionInfo^.SessionId,

WTSUserName, ptr, bytesReturned) then

begin

CurrUsername:=PWideChar(ptr);

If LowerCase(CurrUsername)=LowerCase(Username) then

begin

//Hurray! The username was correct, print it on the GUI and

break the loop..

memo1.lines.add('User '+CurrUsername+' found with ID

'+inttostr(CurrSessionInfo^.SessionId)+' on server "'+Servername+'"');

break;

end;

end;

//Increase the pointer to the next in the enumeration...

inc(CurrSessionInfo);

end;

end;

//Memory management....um...we love it! eh..

WTSFreeMemory(SessionInfo);

finally

WTSCloseServer(ServerHandle);

end;

 

And it works fine...but it ain't pretty! :-)

 

What am i missing here? Has anyone done anything like this and found a

neat "Username to sessionid" method?

 

Thanks!

 

....and again, i'm sorry if this ain't the correct group:-(

 

/Thomas

[Guest Rob Leitman [MS]]

Re: API to get getting sessionid from server+username...? (might be OT?)

 

A user can have more than one session, so I don't see an alternative other

than enumeration.

 

Rob

 

"Thomas Eg Jørgensen" <thomas@hest.notaplan.com> wrote in message

news:47bbec23$0$90266$14726298@news.sunsite.dk...

> Hi,

>

> I've been searching for at better place to ask this question, but i wasn't

> able to find any:-( If you have a better place for this question, please

> let me know...

>

> Anyhow, the question is related to developing custom terminal services

> administration application...

>

> I need to remote control a specific user(defined by the server+username)

> in my software. To be able to remote control a specific user i must know

> the sessionid of the user. However, the API in windows does not allow me

> to query a server for a single username, i must enumerate ALL users and

> thereafter compare EACH enumerated user to see if this user has the

> correct username....

>

> First i must enumerate all sessions on the specific server with:

> BOOL WTSEnumerateSessions(

> __in HANDLE hServer,

> __in DWORD Reserved,

> __in DWORD Version,

> __out PWTS_SESSION_INFO* ppSessionInfo,

> __out DWORD* pCount

> );

> [ http://msdn2.microsoft.com/en-us/library/aa383833(VS.85).aspx ]

>

> ...then i must loop all the users(about 200 per server) and query each of

> them to verify the username with:

> BOOL WTSQuerySessionInformation(

> __in HANDLE hServer,

> __in DWORD SessionId,

> __in WTS_INFO_CLASS WTSInfoClass,

> __out LPTSTR* ppBuffer,

> __out DWORD* pBytesReturned

> );

> [ http://msdn2.microsoft.com/en-us/library/aa383838(VS.85).aspx ]

>

> This can't be right, can it? the above procedure is, ofcourse, very slow.

> About 1 sec to find a random user on a server with about 200 active

> sessions...and that is just to find the correct sessionid!

>

> Here is snippet from my application(Pascal language):

>

> //Open the serverhandle for the server in question...

> ServerHandle=WTSOpenServerW(PWideChar(ServerName));

> try

> //Enumerate all users on the server...

> if WTSEnumerateSessionsW(ServerHandle,0,1,SessionInfo,nCount) then

> begin

> //Set the the "CurrentSessionInformation"-pointer to the first

> pointer returned by the enumeration...

> CurrSessionInfo := SessionInfo;

> //Loop as many times as nCount....one for each session...

> for a:=1 to nCount do

> begin

> //Query the session to get the username...

> if

> WTSQuerySessionInformationW(ServerHandle,CurrSessionInfo^.SessionId,

> WTSUserName, ptr, bytesReturned) then

> begin

> CurrUsername:=PWideChar(ptr);

> If LowerCase(CurrUsername)=LowerCase(Username) then

> begin

> //Hurray! The username was correct, print it on the GUI and

> break the loop..

> memo1.lines.add('User '+CurrUsername+' found with ID

> '+inttostr(CurrSessionInfo^.SessionId)+' on server "'+Servername+'"');

> break;

> end;

> end;

> //Increase the pointer to the next in the enumeration...

> inc(CurrSessionInfo);

> end;

> end;

> //Memory management....um...we love it! eh..

> WTSFreeMemory(SessionInfo);

> finally

> WTSCloseServer(ServerHandle);

> end;

>

> And it works fine...but it ain't pretty! :-)

>

> What am i missing here? Has anyone done anything like this and found a

> neat "Username to sessionid" method?

>

> Thanks!

>

> ...and again, i'm sorry if this ain't the correct group:-(

>

> /Thomas

[Guest Thomas Eg Jørgensen]

Re: API to get getting sessionid from server+username...? (might be OT?)

 

 

"Rob Leitman [MS]" <robleit@online.microsoft.com> skrev i en meddelelse

news:O0PGuUAdIHA.1208@TK2MSFTNGP05.phx.gbl...

>> I need to remote control a specific user(defined by the

>> server+username) in my software. To be able to remote control a

>> specific user i must know the sessionid of the user. However, the API

>> in windows does not allow me to query a server for a single username,

>> i must enumerate ALL users and thereafter compare EACH enumerated

>> user to see if this user has the correct username....

>>

>

> A user can have more than one session, so I don't see an alternative

> other than enumeration.

>

 

ah yes, i did not think of that, but it sounds like that's the reason

why enumeration are necessary...

 

Thanks alot...

 

/Thomas