<div class="content"><p> </p><p>The <b>R_DhcpAddMScopeElement</b> method adds an IPv4
multicast subnet element (IPv4 range or IPv4 exclusion range) to the IPv4
multicast subnet in the MADCAP <span><a href="a9d6a415-4de6-4058-befe-ca2e42764485#gt_434b0234-e970-4e8c-bdfa-e16a30d96703" data-linktype="relative-path">server</a></span>. </p><dl>
<dd>
<div><pre> DWORD R_DhcpAddMScopeElement(
     [in, unique, string]  DHCP_SRV_HANDLE ServerIpAddress,
     [in, ref, string]    LPWSTR *MScopeName,
     [in, ref] LPDHCP_SUBNET_ELEMENT_DATA_V4 AddElementInfo
 );
</pre></div>
</dd></dl><p><b>ServerIpAddress: </b>The IP address/host name of
the MADCAP server. This parameter is unused.</p><p><b>MScopeName: </b>This is a pointer to a Unicode
string that contains the name of the IPv4 multicast subnet in which the element
is added. There is no restriction on the length of this parameter.</p><p><b>AddElementInfo: </b>This is a pointer to a <span><a href="76963288-4666-4dc8-b649-77fd7032bdf7" data-linktype="relative-path">DHCP_SUBNET_ELEMENT_DATA_V4 (section 2.2.1.2.35)</a></span>
structure that contains the IPv4 multicast subnet element that needs to be
added to the IPv4 multicast subnet.</p><p><b>Return Values: </b>A 32-bit unsigned integer value
that indicates return status. A return value of ERROR_SUCCESS (0x00000000)
indicates that the operation was completed successfully, else it contains a
Win32 error code, as specified in <span><a href="../ms-erref/1bc92ddf-b79e-413c-bbaa-99a5281a6c90" data-linktype="relative-path">[MS-ERREF]</a></span>.
This error code value can correspond to a DHCP-specific failure, which takes a
value between 20000 and 20099, or any generic failure. </p><dl>
<dd>
<table><thead>
  <tr>
   <th>
   <p>Return value/code</p>
   </th>
   <th>
   <p>Description</p>
   </th>
  </tr>
 </thead><tbody><tr>
  <td>
  <p>0x00000000</p>
  <p>ERROR_SUCCESS</p>
  </td>
  <td>
  <p>The call was successful.</p>
  </td>
 </tr><tr>
  <td>
  <p>0x00004E25</p>
  <p>ERROR_DHCP_SUBNET_NOT_PRESENT</p>
  </td>
  <td>
  <p>The specified IPv4 subnet does not exist.</p>
  </td>
 </tr><tr>
  <td>
  <p>0x00004E2D</p>
  <p>ERROR_DHCP_JET_ERROR</p>
  </td>
  <td>
  <p>An error occurred while accessing the MADCAP server
  database.</p>
  </td>
 </tr><tr>
  <td>
  <p>0x00004E37</p>
  <p>ERROR_DHCP_INVALID_RANGE</p>
  </td>
  <td>
  <p>The specified multicast range either overlaps an existing
  range or is not valid.</p>
  </td>
 </tr><tr>
  <td>
  <p>0x00004E56</p>
  <p>ERROR_MSCOPE_RANGE_TOO_SMALL</p>
  </td>
  <td>
  <p>The multicast scope range MUST have at least 256 IPv4
  addresses.</p>
  </td>
 </tr><tr>
  <td>
  <p>0x00004E35</p>
  <p>ERROR_DHCP_IPRANGE_EXITS</p>
  </td>
  <td>
  <p>The specified multicast range already exists.</p>
  </td>
 </tr></tbody></table>
</dd></dl><p>The opnum field value for this method is 4.</p><p>When processing this call, the MADCAP server MUST do the
following:</p><ul><li><p><span><span> 
</span></span>Validate if this method is authorized for read/write access per
section <span><a href="38840bd0-0a5a-47ed-bc69-0dd870d33aec" data-linktype="relative-path">3.5.5</a></span>. If not,
return ERROR_ACCESS_DENIED.</p>
</li><li><p><span><span> 
</span></span>If the <i>MScopeName</i> and <i>AddElementInfo</i> parameters are
NULL, return ERROR_INVALID_PARAMETER.</p>
</li><li><p><span><span> 
</span></span>Retrieve the <b>DHCPv4MScope</b> ADM element entry corresponding
to <i>MScopeName</i> from the server ADM element <b>DHCPv4MScopesList</b>.</p>
</li><li><p><span><span> 
</span></span>If the <b>DHCPv4MScope</b> entry is not found, return ERROR_DHCP_SUBNET_NOT_PRESENT.</p>
</li><li><p><span><span> 
</span></span>If the <b>ElementType</b> field in the <i>AddElementInfo</i>
parameter is set to DhcpSecondaryHosts, return ERROR_CALL_NOT_IMPLEMENTED.</p>
</li><li><p><span><span> 
</span></span>If <b>ElementType</b> is set to DhcpReservedIps or
DhcpIpUsedClusters, return ERROR_INVALID_PARAMETER.</p>
</li><li><p><span><span> 
</span></span>If <b>ElementType</b> is set to DhcpIpRanges,
DhcpIpRangesDhcpOnly, DhcpIpRangesDhcpBootp or DhcpIpRangesBootpOnly, and <b>IpRange</b>
is NULL, return ERROR_INVALID_PARAMETER.</p>
</li><li><p><span><span> 
</span></span>If <b>EndAddress</b> of any kind of IPv4 multicast range is less
than <b>StartAddress</b>, return ERROR_DHCP_INVALID_RANGE.</p>
</li><li><p><span><span> 
</span></span>If <b>ElementType</b> is set to DhcpIpRanges, check that the
start and end addresses of the range are valid multicast addresses as defined
in <span><a href="https://go.microsoft.com/fwlink/?LinkId=149638" data-linktype="external">[RFC2780]</a></span>.
That is, the IPv4 addresses fall within the range of 224.0.0.0 through
239.255.255.255. If the check fails, return ERROR_INVALID_PARAMETER.</p>
</li><li><p><span><span> 
</span></span>If the <b>ElementType</b> is set to DhcpIpRanges,
DhcpIpRangesDhcpOnly, DhcpIpRangesBootpOnly, or DhcpIpRangesDhcpBootp, and the
end address falls within the administratively scoped IPv4 multicast address
space, ensure that the range contains 256 or more addresses. The
administratively scoped IPv4 multicast address space ranges from 239.0.0.0
through 239.255.255.255, as defined in <span><a href="https://go.microsoft.com/fwlink/?LinkId=119994" data-linktype="external">[RFC2365]</a></span>. If
the check fails, return ERROR_MSCOPE_RANGE_TOO_SMALL.</p>
</li><li><p><span><span> 
</span></span>If there is a <b>DHCPv4IPRange</b> ADM element entry in <b>DHCPv4MScope.DHCPv4IPRangesList</b>
that has <b>RangeInfo.StartAddress</b> and <i>RangeInfo.EndAddress</i> fields
that match the <b>StartAddress</b> and <b>EndAddress</b> fields of <i>AddElementInfo.IpRange</i>,
return ERROR_DHCP_IPRANGE_EXITS.</p>
</li><li><p><span><span> 
</span></span>If the <b>DHCPv4MScope.DHCPv4IPRangesList</b> ADM element is not
empty and the new IPv4 multicast range is not the same as the <b>DHCPv4IPRange.RangeInfo</b>
of an entry in <b>DHCPv4MScope.DHCPv4IPRangesList</b>, the new IPv4 multicast
range (specified by the <b>StartAddress</b> and <b>EndAddress</b> members of
the <span><a href="29a03b34-249e-4bd8-a118-e708dadbf22b" data-linktype="relative-path">DHCP_IP_RANGE</a></span>
structure) has to either be completely within the range specified by the <b>DHCPv4IPRange</b>
entry or completely contain the range specified by the <b>DHCPv4IPRange</b>
entry; if neither condition is met return error ERROR_DHCP_INVALID_RANGE. </p>
</li><li><p><span><span> 
</span></span>If <b>DHCPv4MScope.DHCPv4IpRangesList</b> is empty, create a new <b>DHCPv4IpRange</b>
object, set the <b>StartAddress</b> and <b>EndAddress</b> fields of <b>DHCPv4IpRange.RangeInfo</b>
to the <b>StartAddress</b> and <b>EndAddress</b> fields of <b>IpRange</b>, <b>DHCPv4IpRange.RangeInfo.BootPAllocated</b>
to 0, <b>DHCPv4IpRange.RangeInfo.MaxBootpAllowed</b> to 0xFFFFFFFF and populate
the <b>DHCPv4IpRange.BitMask</b> with bits corresponding to all the addresses
within the newly created range and initialize each bit to 0 indicating the
availability of its corresponding address for allocation to a MADCAP client.
Insert the new object into <b>DHCPv4MScope.DHCPv4IpRangesList</b>.</p>
</li><li><p><span><span> 
</span></span>If <b>DHCPv4MScope.DHCPv4IpRangesList</b> is not empty, set the <b>StartAddress</b>
and <b>EndAddress</b> of the existing <b>DHCPv4IpRange.RangeInfo</b> to <b>StartAddress</b>
and <b>EndAddress</b> of <b>IpRange</b>, <b>DHCPv4IpRange.RangeInfo.BootPAllocated</b>
to 0 and <b>DHCPv4IpRange.RangeInfo.MaxBootpAllowed</b> to 0xFFFFFFFF. <b>DHCPv4IpRange.BitMask</b>
needs to be expanded or contracted according to the new <b>IpRange.StartAddress</b>
and <b>IpRange.EndAddress</b>. Accordingly, add or remove bits from the <b>DHCPv4IpRange.BitMask</b>.
If adding bits for expansion, initialize them to 0 indicating the availability
of their corresponding addresses for allocation to a MADCAP client.</p>
</li><li><p><span><span> 
</span></span>If the <b>ElementType</b> is DhcpIpRanges and the end address
falls within the administratively scoped IPv4 multicast address space defined
in [RFC2365], then automatically insert an exclusion range for the last 256
elements. Create a <b>DHCPv4ExclusionRange</b> ADM element object and insert it
into an <b>DHCPv4MScope.DHCPv4ExclusionRangesList</b> ADM element. The <b>DHCPv4ExclusionRange</b>
object is initialized as follows:</p>
<ul><li><p><span><span>  </span></span><b>DHCPv4ExclusionRange.StartAddress</b>
is set to <i>AddElementInfo.IpRange.EndAddress</i> – 255.</p>
</li><li><p><span><span>  </span></span><b>DHCPv4ExclusionRange.EndAddress</b>
is set to <i>AddElementInfo.IpRange.EndAddress</i>.</p>
</li></ul></li><li><p><span><span> 
</span></span>If <b>ElementType</b> is set to DhcpExcludedIpRanges, create a <b>DHCPv4ExclusionRange</b>
object, set it to <b>ExcludeIpRange</b>, and insert it into <b>DHCPv4ExclusionRangesList</b>.</p>
</li><li><p><span><span> 
</span></span>Return ERROR_SUCCESS.</p>
</li></ul><p><b>Exceptions Thrown:</b> No exceptions SHOULD be thrown
beyond those thrown by the underlying RPC protocol specified in <span><a href="../ms-rpce/290c38b1-92fe-4229-91e6-4fc376610c15" data-linktype="relative-path">[MS-RPCE]</a></span>.</p></div>