Convert SID string format to bytes array

.net, c#, sid

Solution

You should use `SecurityIdentifier` object from `System.Security.Principal` namespace:

var sid = new SecurityIdentifier("S-1-5-32-544");
byte[] bytes = new byte[sid.BinaryLength];
sid.GetBinaryForm(bytes, 0);

and if you want it as a text, you can then:

string strsid = string.Format("(SID: {0})", string.Join(",", bytes ));

which produces exactly:

(SID: 1,2,0,0,0,0,0,5,32,0,0,0,32,2,0,0)

Moreover, if you want SID of `NT Authority\NetworkService`, you can replace first line with:

var sid = new SecurityIdentifier(WellKnownSidType.NetworkServiceSid, null);

Problem

I want to convert SID string format to bytes array representation which in turn will be supplied to `LookupAccountSid()` method's second argument in C#. But I don't find any particular in built function which can do this. For example: SID = S-1-5-32-544 can be converted into: (SID: 1,2,0,0,0,0,0,5,32,0,0,0,32,2,0,0) I saw it in some posts. but how? Is there a easy way to achieve this? Basically I want the byte array representation of the `NT Authority\NetworkService` which is `SID = S-1-5-20`. Thanks in advance for your help.

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