Credentials for network shares

[GCeaser@aol.com]

All,
I have a situation where a Server exists in a stand alone workgroup
on an Active Directory domain. The server can access domain resources
with the correct domain security information provided (for example I
can map a drive from the server to a server in the AD by connecting as
a different user and providing credentials that the AD can
authenticate.)

The challenge is that I want to access a domain network share
programmaticall y via C# from the workgroup server. Does anyone know
how I can programmaticall y map to the drive and provide the domain
credentials?

Thanks
George

[Willy Denoyette [MVP]]

Re: Credentials for network shares


<GCeaser@aol.co m> wrote in message
news:1107192680 .691317.171590@ c13g2000cwb.goo glegroups.com.. .[color=blue]
> All,
> I have a situation where a Server exists in a stand alone workgroup
> on an Active Directory domain. The server can access domain resources
> with the correct domain security information provided (for example I
> can map a drive from the server to a server in the AD by connecting as
> a different user and providing credentials that the AD can
> authenticate.)
>
> The challenge is that I want to access a domain network share
> programmaticall y via C# from the workgroup server. Does anyone know
> how I can programmaticall y map to the drive and provide the domain
> credentials?
>
> Thanks
> George[/color]

You have multiple options to access a remote file share, here are a few:
1. Map the drive in a Logonscript.
2. User Process.Start to execute "net use \\xxxx\yyyy password /user:uuuu
...."
3. When running XP or higher create a logon session by calling LogonUser
with Logontype LOGON32_LOGON_N EW_CREDENTIALS. This returns a token with
network access privileges using the credentilas specified, but it keeps the
user token for local access checks.
4. Use Pinvoke to call Win32 API NetUseAdd(...) and USE_INFO_2 structure.

Herewith a sample:

[StructLayout(La youtKind.Sequen tial,CharSet=Ch arSet.Auto)]
struct _USE_INFO_2
{
internal string ui2_local;
internal string ui2_remote;
internal IntPtr ui2_password; // don't pass a string or StringBuilder
here!!
internal uint ui2_status;
internal uint ui2_asg_type;
internal uint ui2_refcount;
internal uint ui2_usecount;
internal string ui2_username;
internal string ui2_domainname;
}

[DllImport("neta pi32", SetLastError=tr ue),
SuppressUnmanag edCodeSecurityA ttribute]
static extern int NetUseAdd(
string UncServerName, // not used
int Level, // use info struct
IntPtr Buf, // Buffer
ref int ParmError
);

// Establish a use record
public static void UseRecord(strin g remotePath, string user, string
password, string domain)
{
int ret = 0;
int paramError = 0;
_USE_INFO_2 use2 = new _USE_INFO_2();
IntPtr pBuf = IntPtr.Zero;
use2.ui2_passwo rd = IntPtr.Zero;
pBuf = Marshal.AllocHG lobal(Marshal.S izeOf(use2));
use2.ui2_local = null;
use2.ui2_asg_ty pe = USE_WILDCARD;
use2.ui2_remote = remotePath;
use2.ui2_passwo rd = Marshal.StringT oHGlobalAuto(pa ssword);
use2.ui2_userna me = user;
use2.ui2_domain name = domain;
Marshal.Structu reToPtr(use2, pBuf, true);
ret = NetUseAdd(null, 2, pBuf, ref paramError);
if(ret != 0)
{
throw new Exception(new
Win32Exception( Marshal.GetLast Win32Error()).M essage);
}
}
finally
{
Marshal.FreeHGl obal(use2.ui2_p assword);
Marshal.FreeHGl obal(pBuf);
}
}

Usage:
UseRecord("\\\\ server\\share", "userName", "pwd", "domain");

Willy.