ConvertByteToStringSid C#

ConvertByteToStringSid.md

Reference from original https://www.codeproject.com/articles/3688/how-to-get-user-sid-using-directoryservices-classe

And SecurityIdentifier in System.Security.Principal.Windows from https://github.com/dotnet/runtime/blob/6bc6560e51d1cf58b54561f7be44801864479b8d/src/libraries/System.Security.Principal.Windows/src/System/Security/Principal/SID.cs#L403-L478

LdapHelper.cs

public static class LdapHelper
{
    // https://www.codeproject.com/Articles/3688/How-to-get-user-SID-using-DirectoryServices-classe
    public static string ConvertByteToStringSid(byte[] sidBytes)
    {
        if (sidBytes == null || sidBytes.Length < 8 ||
            sidBytes.Length > 68)   // maximum 15 sub authorities
            return string.Empty;

        var span = new ReadOnlySpan<byte>(sidBytes);

        var strSid = new StringBuilder("S-");

        // Add SID revision.
        strSid.Append(span[0]);

        // Get sub authority count...
        var subAuthoritiesLength = Convert.ToInt32(span[1]);
        if (sidBytes.Length != 8 + subAuthoritiesLength * 4)
            return string.Empty;

        long identifierAuthority =
            (((long)span[2]) << 40) +
            (((long)span[3]) << 32) +
            (((long)span[4]) << 24) +
            (((long)span[5]) << 16) +
            (((long)span[6]) << 8) +
            span[7];
        strSid.Append('-');
        strSid.Append(identifierAuthority);

        span = span[8..];

        for (int i = 0; i < subAuthoritiesLength; i++, span = span[4..])
        {
            strSid.Append('-');
            strSid.Append(BitConverter.ToUInt32(span.Slice(0, 4)));
        }

        return strSid.ToString();
    }
}

LdapHelperTest.cs

public class LdapHelperTest
{
    private static Func<byte[], string> GetConvertByteToStringSidService() => LdapHelper.ConvertByteToStringSid;

    [Fact]
    public void ConvertByteToStringSid_Builtin()
    {
        var service = GetConvertByteToStringSidService();
        var sid = new byte[] { 1, 2, 0, 0, 0, 0, 0, 5, 32, 0, 0, 0, 39, 2, 0, 0 };
        var result = service(sid);
        Assert.Equal("S-1-5-32-551", result);
    }

    [Fact]
    [SupportedOSPlatform("windows")]
    public void ConvertByteToStringSid_Builtin_Windows()
    {
        var sid = new byte[] { 1, 2, 0, 0, 0, 0, 0, 5, 32, 0, 0, 0, 39, 2, 0, 0 };
        var s2 = new SecurityIdentifier(sid, 0);
        Assert.Equal("S-1-5-32-551", s2.ToString());
    }

    [Fact]
    public void ConvertByteToStringSid_Malformed()
    {
        var service = GetConvertByteToStringSidService();

        var sid1 = new byte[] { 1, 5, 0, 0, 0, 0, 0, 5, 21, 0, 0, 0, 222, 206, 60, 4, 227, 115, 59, 3, 168, 94, 83, 2, 1, 4, 0, 0, 1 };
        var result1 = service(sid1);
        Assert.Equal("", result1);

        var sid2 = new byte[] { 1, 5, 0, 0, 0, 0, 0, 5, 21, 0, 0, 0, 222, 206, 60, 4, 227, 115, 59, 3, 168, 94, 83, 2, 1, 4, 0 };
        var result2 = service(sid2);
        Assert.Equal("", result2);

        var sid3 = new byte[] { 1, 4, 0, 0, 0, 0, 0, 5, 21, 0, 0, 0, 222, 206, 60, 4, 227, 115, 59, 3, 168, 94, 83, 2, 1, 4, 0, 0 };
        var result3 = service(sid3);
        Assert.Equal("", result3);
    }

    [Fact]
    public void ConvertByteToStringSid_Max()
    {
        var service = GetConvertByteToStringSidService();

        var sid = new byte[] { 1, 1, 255, 254, 253, 252, 0, 0, 251, 250, 249, 248 };
        var result = service(sid);
        Assert.Equal("S-1-281470647926784-4177132283", result);

        var sid2 = new byte[] { 1, 5, 136, 0, 44, 89, 0xFE, 5, 21, 0, 0, 0, 222, 206, 60, 4, 227, 115, 59, 3, 168, 94, 83, 2, 1, 4, 0, 0 };
        var result2 = service(sid2);
        Assert.Equal("S-1-149534325472773-21-71093982-54227939-39018152-1025", result2);
    }

    [Fact]
    [SupportedOSPlatform("windows")]
    public void ConvertByteToStringSid_Max_Windows()
    {
        var sid = new byte[] { 1, 1, 255, 254, 253, 252, 0, 0, 251, 250, 249, 248 };
        var s1 = new SecurityIdentifier(sid, 0);
        Assert.Equal("S-1-281470647926784-4177132283", s1.ToString());

        var sid2 = new byte[] { 1, 5, 136, 0, 44, 89, 0xFE, 5, 21, 0, 0, 0, 222, 206, 60, 4, 227, 115, 59, 3, 168, 94, 83, 2, 1, 4, 0, 0 };
        var s2 = new SecurityIdentifier(sid2, 0);
        Assert.Equal("S-1-149534325472773-21-71093982-54227939-39018152-1025", s2.ToString());
    }

    [Fact]
    public void ConvertByteToStringSid_NullEmpty()
    {
        var service = GetConvertByteToStringSidService();

        var sid1 = Array.Empty<byte>();
        var result1 = service(sid1);
        Assert.Equal("", result1);

        var result2 = service(null);
        Assert.Equal("", result2);
    }

    [Fact]
    public void ConvertByteToStringSid_Success()
    {
        var service = GetConvertByteToStringSidService();
        var sid = new byte[] { 1, 5, 0, 0, 0, 0, 0, 5, 21, 0, 0, 0, 222, 206, 60, 4, 227, 115, 59, 3, 168, 94, 83, 2, 1, 4, 0, 0 };
        var result = service(sid);
        Assert.Equal("S-1-5-21-71093982-54227939-39018152-1025", result);
    }

    [Fact]
    [SupportedOSPlatform("windows")]
    public void ConvertByteToStringSid_Windows()
    {
        var sid = new byte[] { 1, 5, 0, 0, 0, 0, 0, 5, 21, 0, 0, 0, 222, 206, 60, 4, 227, 115, 59, 3, 168, 94, 83, 2, 1, 4, 0, 0 };
        var s1 = new SecurityIdentifier(sid, 0);
        Assert.Equal("S-1-5-21-71093982-54227939-39018152-1025", s1.ToString());
    }
}

Thanks!!!

Thanks, the code help me.