<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<title>libnl: Core Netlink API</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="doxygen.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<!-- Generated by Doxygen 1.7.3 -->
<div id="top">
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td style="padding-left: 0.5em;">
<div id="projectname">libnl <span id="projectnumber">1.1</span></div>
</td>
</tr>
</tbody>
</table>
</div>
<div id="navrow1" class="tabs">
<ul class="tablist">
<li><a href="index.html"><span>Main Page</span></a></li>
<li><a href="modules.html"><span>Modules</span></a></li>
<li><a href="annotated.html"><span>Data Structures</span></a></li>
<li><a href="files.html"><span>Files</span></a></li>
</ul>
</div>
</div>
<div class="header">
<div class="summary">
<a href="#nested-classes">Data Structures</a> |
<a href="#groups">Modules</a> </div>
<div class="headertitle">
<h1>Core Netlink API</h1> </div>
</div>
<div class="contents">
<table class="memberdecls">
<tr><td colspan="2"><h2><a name="nested-classes"></a>
Data Structures</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">struct  </td><td class="memItemRight" valign="bottom"><a class="el" href="structsockaddr__nl.html">sockaddr_nl</a></td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Netlink socket address. <a href="structsockaddr__nl.html#_details">More...</a><br/></td></tr>
<tr><td colspan="2"><h2><a name="groups"></a>
Modules</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__cb.html">Callbacks/Customization</a></td></tr>
<p><tr><td class="mdescLeft"> </td><td class="mdescRight"><p>Callbacks and overwriting capabilities are provided to take influence in various control flows inside the library. </p>
<br/></td></tr>
</p>
<tr><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__msg.html">Messages</a></td></tr>
<p><tr><td class="mdescLeft"> </td><td class="mdescRight"><p>Netlink Message Construction/Parsing Interface. </p>
<br/></td></tr>
</p>
<tr><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="group__socket.html">Socket</a></td></tr>
<p><tr><td class="mdescLeft"> </td><td class="mdescRight"><p>Handle representing a netlink socket. </p>
<br/></td></tr>
</p>
<tr><td colspan="2"><h2><a name="member-group"></a>
Connection Management</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga68655d7fa8bd1944bec4761c95e576e9">nl_connect</a> (struct nl_handle *handle, int protocol)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Create and connect netlink socket. <a href="#ga68655d7fa8bd1944bec4761c95e576e9"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga25039e93db5ab64ce4345ffe14379530">nl_close</a> (struct nl_handle *handle)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Close/Disconnect netlink socket. <a href="#ga25039e93db5ab64ce4345ffe14379530"></a><br/></td></tr>
<tr><td colspan="2"><h2><a name="member-group"></a>
Send</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga53ee384f123fa3c354ad43adb6cf647d">nl_sendto</a> (struct nl_handle *handle, void *buf, size_t size)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Send raw data over netlink socket. <a href="#ga53ee384f123fa3c354ad43adb6cf647d"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#gaf3dca993337ed2d60a42269eaab65585">nl_sendmsg</a> (struct nl_handle *handle, struct nl_msg *msg, struct msghdr *hdr)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Send netlink message with control over sendmsg() message header. <a href="#gaf3dca993337ed2d60a42269eaab65585"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga5f3fff85c39f18946100c85f09d2c41c">nl_send</a> (struct nl_handle *handle, struct nl_msg *msg)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Send netlink message. <a href="#ga5f3fff85c39f18946100c85f09d2c41c"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga01a2aad82350f867e704d5c696438b60">nl_send_auto_complete</a> (struct nl_handle *handle, struct nl_msg *msg)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Send netlink message and check & extend header values as needed. <a href="#ga01a2aad82350f867e704d5c696438b60"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga73ed88a505f2d67bcf328183fe1e692a">nl_send_simple</a> (struct nl_handle *handle, int type, int flags, void *buf, size_t size)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Send simple netlink message using <a class="el" href="group__nl.html#ga01a2aad82350f867e704d5c696438b60" title="Send netlink message and check & extend header values as needed.">nl_send_auto_complete()</a> <a href="#ga73ed88a505f2d67bcf328183fe1e692a"></a><br/></td></tr>
<tr><td colspan="2"><h2><a name="member-group"></a>
Receive</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga060acc8371fdb242c5ae3d5b761d28e1">nl_recv</a> (struct nl_handle *handle, struct <a class="el" href="structsockaddr__nl.html">sockaddr_nl</a> *nla, unsigned char **buf, struct ucred **creds)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Receive data from netlink socket. <a href="#ga060acc8371fdb242c5ae3d5b761d28e1"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#ga1bb066e1772b89f79fe1d76a4ef243a6">nl_recvmsgs</a> (struct nl_handle *handle, struct nl_cb *cb)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Receive a set of messages from a netlink socket. <a href="#ga1bb066e1772b89f79fe1d76a4ef243a6"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#gab287fc77c46d80c4e22bc87494cbf853">nl_recvmsgs_default</a> (struct nl_handle *handle)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Receive a set of message from a netlink socket using handlers in nl_handle. <a href="#gab287fc77c46d80c4e22bc87494cbf853"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="group__nl.html#gaa65fec588e0a0a2de1881fb8366ccd79">nl_wait_for_ack</a> (struct nl_handle *handle)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Wait for ACK. <a href="#gaa65fec588e0a0a2de1881fb8366ccd79"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><b>NL_CB_CALL</b>(cb, type, msg)</td></tr>
</table>
<hr/><a name="_details"></a><h2>Detailed Description</h2>
<dl class="user"><dt><b>Receiving Semantics</b></dt><dd><div class="fragment"><pre class="fragment"> <a class="code" href="group__nl.html#gab287fc77c46d80c4e22bc87494cbf853" title="Receive a set of message from a netlink socket using handlers in nl_handle.">nl_recvmsgs_default</a>(socket)
|
| cb = nl_socket_get_cb(socket)
v
<a class="code" href="group__nl.html#ga1bb066e1772b89f79fe1d76a4ef243a6" title="Receive a set of messages from a netlink socket.">nl_recvmsgs</a>(socket, cb)
| [Application provides <a class="code" href="group__nl.html#ga1bb066e1772b89f79fe1d76a4ef243a6" title="Receive a set of messages from a netlink socket.">nl_recvmsgs</a>() replacement]
|- - - - - - - - - - - - - - - v
| cb->cb_recvmsgs_ow()
|
| [Application provides <a class="code" href="group__nl.html#ga060acc8371fdb242c5ae3d5b761d28e1" title="Receive data from netlink socket.">nl_recv</a>() replacement]
+-------------->|- - - - - - - - - - - - - - - v
| <a class="code" href="group__nl.html#ga060acc8371fdb242c5ae3d5b761d28e1" title="Receive data from netlink socket.">nl_recv</a>() cb->cb_recv_ow()
| +----------->|<- - - - - - - - - - - - - - -+
| | v
| | Parse Message
| | |- - - - - - - - - - - - - - - v
| | | <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a160d69995bab2c325bd25d7ee2d5292d" title="Called for every message received.">NL_CB_MSG_IN</a>()
| | |<- - - - - - - - - - - - - - -+
| | |
| | |- - - - - - - - - - - - - - - v
| | Sequence Check <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363ae73e906b997f00e8911b09e0f254364d" title="Called instead of internal sequence number checking.">NL_CB_SEQ_CHECK</a>()
| | |<- - - - - - - - - - - - - - -+
| | |
| | |- - - - - - - - - - - - - - - v [ <a class="code" href="group__msg.html#ga67d5b6ba8714b97d74df72d119351bee" title="Request for an acknowledgment on success.">NLM_F_ACK</a> is set ]
| | | <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363af2930b7775d1444c359cd11d7ce2cd02" title="Sending of an acknowledge message has been requested.">NL_CB_SEND_ACK</a>()
| | |<- - - - - - - - - - - - - - -+
| | |
| | +-----+------+--------------+----------------+--------------+
| | v v v v v
| | Valid Message ACK NOOP Message End of Multipart Error Message
| | | | | | |
| | v v v v v
| |<a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a6e1f371d16186a460f25ea9bb1306c47" title="Message is valid.">NL_CB_VALID</a>() <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a8295b387c07bd076ccdee45b555f1134" title="Message is an acknowledge.">NL_CB_ACK</a>() <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a034ec83d5ba891deb3d3e54f9e15d3a0" title="Message wants to be skipped.">NL_CB_SKIPPED</a>() <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a044400d11ee451b692333a0d95cf3d32" title="Last message in a series of multi part messages received.">NL_CB_FINISH</a>() cb->cb_err()
| | | | | | |
| | +------------+--------------+----------------+ v
| | | (FAILURE)
| | | [Callback returned <a class="code" href="group__cb.html#gga0c50cb29c507b3d7e8bc7d76c74675f8af77d78aac004c6d4bee57741d3a295ae" title="Skip this message.">NL_SKIP</a>]
| | [More messages to be parsed] |<-----------
| +----------------------------------|
| |
| [Multipart message] |
+-------------------------------------| [Callback returned <a class="code" href="group__cb.html#gga0c50cb29c507b3d7e8bc7d76c74675f8aa87c4bfa1b41e2e06286a412dc2bc17b" title="Stop parsing altogether and discard remaining messages.">NL_STOP</a>]
|<-----------
v
(SUCCESS)
At any time:
Message Format Error
|- - - - - - - - - - - - v
v <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363af5b5448bf122561db88d510e5d153a8a" title="Message is malformed and invalid.">NL_CB_INVALID</a>()
(FAILURE)
Message Overrun (Kernel Lost Data)
|- - - - - - - - - - - - v
v <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a25c8376dc758b16bcaeb76c329719dae" title="Report received that data was lost.">NL_CB_OVERRUN</a>()
(FAILURE)
Callback returned negative error code
(FAILURE)
</pre></div></dd></dl>
<dl class="user"><dt><b>Sending Semantics</b></dt><dd><div class="fragment"><pre class="fragment"> <a class="code" href="group__nl.html#ga01a2aad82350f867e704d5c696438b60" title="Send netlink message and check &amp; extend header values as needed.">nl_send_auto_complete</a>()
|
| Automatically fill in PID and/or sequence number
|
| [Application provides <a class="code" href="group__nl.html#ga5f3fff85c39f18946100c85f09d2c41c" title="Send netlink message.">nl_send</a>() replacement]
|- - - - - - - - - - - - - - - - - - - - v
v cb->cb_send_ow()
<a class="code" href="group__nl.html#ga5f3fff85c39f18946100c85f09d2c41c" title="Send netlink message.">nl_send</a>()
| Add destination address and credentials
v
<a class="code" href="group__nl.html#gaf3dca993337ed2d60a42269eaab65585" title="Send netlink message with control over sendmsg() message header.">nl_sendmsg</a>()
| Set source address
|
|- - - - - - - - - - - - - - - - - - - - v
| <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a0b43ab5eccae67470bb8ed0b09e2f650" title="Called for every message sent out except for nl_sendto()">NL_CB_MSG_OUT</a>()
|<- - - - - - - - - - - - - - - - - - - -+
v
sendmsg()
</pre></div></dd></dl>
<dl class="user"><dt><b>1) Connecting the socket</b></dt><dd><div class="fragment"><pre class="fragment"> <span class="comment">// Bind and connect the socket to a protocol, NETLINK_ROUTE in this example.</span>
<a class="code" href="group__nl.html#ga68655d7fa8bd1944bec4761c95e576e9" title="Create and connect netlink socket.">nl_connect</a>(handle, NETLINK_ROUTE);
</pre></div></dd></dl>
<dl class="user"><dt><b>2) Sending data</b></dt><dd><div class="fragment"><pre class="fragment"> <span class="comment">// The most rudimentary method is to use nl_sendto() simply pushing</span>
<span class="comment">// a piece of data to the other netlink peer. This method is not</span>
<span class="comment">// recommended.</span>
<span class="keyword">const</span> <span class="keywordtype">char</span> buf[] = { 0x01, 0x02, 0x03, 0x04 };
<a class="code" href="group__nl.html#ga53ee384f123fa3c354ad43adb6cf647d" title="Send raw data over netlink socket.">nl_sendto</a>(handle, buf, <span class="keyword">sizeof</span>(buf));
<span class="comment">// A more comfortable interface is nl_send() taking a pointer to</span>
<span class="comment">// a netlink message.</span>
<span class="keyword">struct </span>nl_msg *msg = my_msg_builder();
<a class="code" href="group__nl.html#ga5f3fff85c39f18946100c85f09d2c41c" title="Send netlink message.">nl_send</a>(handle, <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg));
<span class="comment">// nl_sendmsg() provides additional control over the sendmsg() message</span>
<span class="comment">// header in order to allow more specific addressing of multiple peers etc.</span>
<span class="keyword">struct </span>msghdr hdr = { ... };
<a class="code" href="group__nl.html#gaf3dca993337ed2d60a42269eaab65585" title="Send netlink message with control over sendmsg() message header.">nl_sendmsg</a>(handle, <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg), &hdr);
<span class="comment">// You're probably too lazy to fill out the netlink pid, sequence number</span>
<span class="comment">// and message flags all the time. nl_send_auto_complete() automatically</span>
<span class="comment">// extends your message header as needed with an appropriate sequence</span>
<span class="comment">// number, the netlink pid stored in the netlink handle and the message</span>
<span class="comment">// flags NLM_F_REQUEST and NLM_F_ACK</span>
<a class="code" href="group__nl.html#ga01a2aad82350f867e704d5c696438b60" title="Send netlink message and check &amp; extend header values as needed.">nl_send_auto_complete</a>(handle, <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg));
<span class="comment">// Simple protocols don't require the complex message construction interface</span>
<span class="comment">// and may favour nl_send_simple() to easly send a bunch of payload</span>
<span class="comment">// encapsulated in a netlink message header.</span>
<a class="code" href="group__nl.html#ga73ed88a505f2d67bcf328183fe1e692a" title="Send simple netlink message using nl_send_auto_complete()">nl_send_simple</a>(handle, MY_MSG_TYPE, 0, buf, <span class="keyword">sizeof</span>(buf));
</pre></div></dd></dl>
<dl class="user"><dt><b>3) Receiving data</b></dt><dd><div class="fragment"><pre class="fragment"> <span class="comment">// nl_recv() receives a single message allocating a buffer for the message</span>
<span class="comment">// content and gives back the pointer to you.</span>
<span class="keyword">struct </span><a class="code" href="structsockaddr__nl.html" title="Netlink socket address.">sockaddr_nl</a> peer;
<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> *msg;
<a class="code" href="group__nl.html#ga060acc8371fdb242c5ae3d5b761d28e1" title="Receive data from netlink socket.">nl_recv</a>(handle, &peer, &msg);
<span class="comment">// nl_recvmsgs() receives a bunch of messages until the callback system</span>
<span class="comment">// orders it to state, usually after receving a compolete multi part</span>
<span class="comment">// message series.</span>
<a class="code" href="group__nl.html#ga1bb066e1772b89f79fe1d76a4ef243a6" title="Receive a set of messages from a netlink socket.">nl_recvmsgs</a>(handle, my_callback_configuration);
<span class="comment">// nl_recvmsgs_default() acts just like nl_recvmsg() but uses the callback</span>
<span class="comment">// configuration stored in the handle.</span>
<a class="code" href="group__nl.html#gab287fc77c46d80c4e22bc87494cbf853" title="Receive a set of message from a netlink socket using handlers in nl_handle.">nl_recvmsgs_default</a>(handle);
<span class="comment">// In case you want to wait for the ACK to be recieved that you requested</span>
<span class="comment">// with your latest message, you can call nl_wait_for_ack()</span>
<a class="code" href="group__nl.html#gaa65fec588e0a0a2de1881fb8366ccd79" title="Wait for ACK.">nl_wait_for_ack</a>(handle);
</pre></div></dd></dl>
<dl class="user"><dt><b>4) Closing</b></dt><dd><div class="fragment"><pre class="fragment"> <span class="comment">// Close the socket first to release kernel memory</span>
<a class="code" href="group__nl.html#ga25039e93db5ab64ce4345ffe14379530" title="Close/Disconnect netlink socket.">nl_close</a>(handle);
</pre></div> </dd></dl>
<hr/><h2>Define Documentation</h2>
<a class="anchor" id="ga8692eaac9695251616b5a826ebc23b70"></a><!-- doxytag: member="nl.c::NL_CB_CALL" ref="ga8692eaac9695251616b5a826ebc23b70" args="(cb, type, msg)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">#define NL_CB_CALL</td>
<td>(</td>
<td class="paramtype"> </td>
<td class="paramname">cb, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"> </td>
<td class="paramname">type, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"> </td>
<td class="paramname">msg </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<b>Value:</b><div class="fragment"><pre class="fragment"><span class="keywordflow">do</span> { \
err = nl_cb_call(cb, type, msg); \
<span class="keywordflow">switch</span> (err) { \
<span class="keywordflow">case</span> <a class="code" href="group__cb.html#gga0c50cb29c507b3d7e8bc7d76c74675f8abce22d25ef3e2fed30f22f8bc27fc8f0" title="Proceed with wathever would come next.">NL_OK</a>: \
err = 0; \
<span class="keywordflow">break</span>; \
<span class="keywordflow">case</span> <a class="code" href="group__cb.html#gga0c50cb29c507b3d7e8bc7d76c74675f8af77d78aac004c6d4bee57741d3a295ae" title="Skip this message.">NL_SKIP</a>: \
<span class="keywordflow">goto</span> skip; \
<span class="keywordflow">case</span> <a class="code" href="group__cb.html#gga0c50cb29c507b3d7e8bc7d76c74675f8aa87c4bfa1b41e2e06286a412dc2bc17b" title="Stop parsing altogether and discard remaining messages.">NL_STOP</a>: \
<span class="keywordflow">goto</span> stop; \
<span class="keywordflow">default</span>: \
<span class="keywordflow">goto</span> out; \
} \
} <span class="keywordflow">while</span> (0)
</pre></div>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00551">551</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
</div>
</div>
<hr/><h2>Function Documentation</h2>
<a class="anchor" id="ga68655d7fa8bd1944bec4761c95e576e9"></a><!-- doxytag: member="nl.c::nl_connect" ref="ga68655d7fa8bd1944bec4761c95e576e9" args="(struct nl_handle *handle, int protocol)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_connect </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int </td>
<td class="paramname"><em>protocol</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle. </td></tr>
<tr><td class="paramname">protocol</td><td>Netlink protocol to use.</td></tr>
</table>
</dd>
</dl>
<p>Creates a netlink socket using the specified protocol, binds the socket and issues a connection attempt.</p>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success or a negative error code. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00191">191</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>References <a class="el" href="socket_8c_source.html#l00532">nl_set_buffer_size()</a>.</p>
<p>Referenced by <a class="el" href="nfnl_8c_source.html#l00085">nfnl_connect()</a>, and <a class="el" href="cache__mngr_8c_source.html#l00149">nl_cache_mngr_alloc()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordtype">int</span> err;
socklen_t addrlen;
handle->h_fd = socket(AF_NETLINK, SOCK_RAW, protocol);
<span class="keywordflow">if</span> (handle->h_fd < 0) {
err = nl_error(1, <span class="stringliteral">"socket(AF_NETLINK, ...) failed"</span>);
<span class="keywordflow">goto</span> errout;
}
<span class="keywordflow">if</span> (!(handle->h_flags & NL_SOCK_BUFSIZE_SET)) {
err = <a class="code" href="group__socket.html#ga0b6d4741ee2ec8f0392b600a626ff1fd" title="Set socket buffer size of netlink handle.">nl_set_buffer_size</a>(handle, 0, 0);
<span class="keywordflow">if</span> (err < 0)
<span class="keywordflow">goto</span> errout;
}
err = bind(handle->h_fd, (<span class="keyword">struct</span> sockaddr*) &handle->h_local,
<span class="keyword">sizeof</span>(handle->h_local));
<span class="keywordflow">if</span> (err < 0) {
err = nl_error(1, <span class="stringliteral">"bind() failed"</span>);
<span class="keywordflow">goto</span> errout;
}
addrlen = <span class="keyword">sizeof</span>(handle->h_local);
err = getsockname(handle->h_fd, (<span class="keyword">struct</span> sockaddr *) &handle->h_local,
&addrlen);
<span class="keywordflow">if</span> (err < 0) {
err = nl_error(1, <span class="stringliteral">"getsockname failed"</span>);
<span class="keywordflow">goto</span> errout;
}
<span class="keywordflow">if</span> (addrlen != <span class="keyword">sizeof</span>(handle->h_local)) {
err = nl_error(EADDRNOTAVAIL, <span class="stringliteral">"Invalid address length"</span>);
<span class="keywordflow">goto</span> errout;
}
<span class="keywordflow">if</span> (handle->h_local.nl_family != AF_NETLINK) {
err = nl_error(EPFNOSUPPORT, <span class="stringliteral">"Address format not supported"</span>);
<span class="keywordflow">goto</span> errout;
}
handle->h_proto = protocol;
<span class="keywordflow">return</span> 0;
errout:
close(handle->h_fd);
handle->h_fd = -1;
<span class="keywordflow">return</span> err;
}
</pre></div>
</div>
</div>
<a class="anchor" id="ga25039e93db5ab64ce4345ffe14379530"></a><!-- doxytag: member="nl.c::nl_close" ref="ga25039e93db5ab64ce4345ffe14379530" args="(struct nl_handle *handle)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void nl_close </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em></td><td>)</td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle </td></tr>
</table>
</dd>
</dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00247">247</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>Referenced by <a class="el" href="cache__mngr_8c_source.html#l00373">nl_cache_mngr_free()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordflow">if</span> (handle->h_fd >= 0) {
close(handle->h_fd);
handle->h_fd = -1;
}
handle->h_proto = 0;
}
</pre></div>
</div>
</div>
<a class="anchor" id="ga53ee384f123fa3c354ad43adb6cf647d"></a><!-- doxytag: member="nl.c::nl_sendto" ref="ga53ee384f123fa3c354ad43adb6cf647d" args="(struct nl_handle *handle, void *buf, size_t size)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_sendto </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">void * </td>
<td class="paramname"><em>buf</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t </td>
<td class="paramname"><em>size</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle. </td></tr>
<tr><td class="paramname">buf</td><td>Data buffer. </td></tr>
<tr><td class="paramname">size</td><td>Size of data buffer. </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>Number of characters written on success or a negative error code. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00271">271</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordtype">int</span> ret;
ret = sendto(handle->h_fd, buf, size, 0, (<span class="keyword">struct</span> sockaddr *)
&handle->h_peer, <span class="keyword">sizeof</span>(handle->h_peer));
<span class="keywordflow">if</span> (ret < 0)
<span class="keywordflow">return</span> nl_errno(errno);
<span class="keywordflow">return</span> ret;
}
</pre></div>
</div>
</div>
<a class="anchor" id="gaf3dca993337ed2d60a42269eaab65585"></a><!-- doxytag: member="nl.c::nl_sendmsg" ref="gaf3dca993337ed2d60a42269eaab65585" args="(struct nl_handle *handle, struct nl_msg *msg, struct msghdr *hdr)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_sendmsg </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">struct nl_msg * </td>
<td class="paramname"><em>msg</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">struct msghdr * </td>
<td class="paramname"><em>hdr</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle. </td></tr>
<tr><td class="paramname">msg</td><td>Netlink message to be sent. </td></tr>
<tr><td class="paramname">hdr</td><td>Sendmsg() message header. </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>Number of characters sent on sucess or a negative error code. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00290">290</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>References <a class="el" href="handlers_8h_source.html#l00107">NL_CB_MSG_OUT</a>, <a class="el" href="handlers_8h_source.html#l00060">NL_OK</a>, <a class="el" href="msg_8c_source.html#l00643">nlmsg_hdr()</a>, and <a class="el" href="netlink-kernel_8h_source.html#l00032">nlmsghdr::nlmsg_len</a>.</p>
<p>Referenced by <a class="el" href="nl_8c_source.html#l00325">nl_send()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keyword">struct </span>nl_cb *cb;
<span class="keywordtype">int</span> ret;
<span class="keyword">struct </span>iovec iov = {
.iov_base = (<span class="keywordtype">void</span> *) <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg),
.iov_len = <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg)-><a class="code" href="structnlmsghdr.html#a5a3fdb3436743ec73e75471c899fd4bc" title="Length of message including header.">nlmsg_len</a>,
};
hdr->msg_iov = &iov;
hdr->msg_iovlen = 1;
nlmsg_set_src(msg, &handle->h_local);
cb = handle->h_cb;
<span class="keywordflow">if</span> (cb->cb_set[<a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a0b43ab5eccae67470bb8ed0b09e2f650" title="Called for every message sent out except for nl_sendto()">NL_CB_MSG_OUT</a>])
<span class="keywordflow">if</span> (nl_cb_call(cb, <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a0b43ab5eccae67470bb8ed0b09e2f650" title="Called for every message sent out except for nl_sendto()">NL_CB_MSG_OUT</a>, msg) != <a class="code" href="group__cb.html#gga0c50cb29c507b3d7e8bc7d76c74675f8abce22d25ef3e2fed30f22f8bc27fc8f0" title="Proceed with wathever would come next.">NL_OK</a>)
<span class="keywordflow">return</span> 0;
ret = sendmsg(handle->h_fd, hdr, 0);
<span class="keywordflow">if</span> (ret < 0)
<span class="keywordflow">return</span> nl_errno(errno);
<span class="keywordflow">return</span> ret;
}
</pre></div>
</div>
</div>
<a class="anchor" id="ga5f3fff85c39f18946100c85f09d2c41c"></a><!-- doxytag: member="nl.c::nl_send" ref="ga5f3fff85c39f18946100c85f09d2c41c" args="(struct nl_handle *handle, struct nl_msg *msg)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_send </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">struct nl_msg * </td>
<td class="paramname"><em>msg</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle </td></tr>
<tr><td class="paramname">msg</td><td>Netlink message to be sent. </td></tr>
</table>
</dd>
</dl>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="group__nl.html#gaf3dca993337ed2d60a42269eaab65585" title="Send netlink message with control over sendmsg() message header.">nl_sendmsg()</a> </dd></dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>Number of characters sent on success or a negative error code. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00325">325</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>References <a class="el" href="netlink-kernel_8h_source.html#l00011">sockaddr_nl::nl_family</a>, and <a class="el" href="nl_8c_source.html#l00290">nl_sendmsg()</a>.</p>
<p>Referenced by <a class="el" href="nl_8c_source.html#l00373">nl_send_auto_complete()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keyword">struct </span><a class="code" href="structsockaddr__nl.html" title="Netlink socket address.">sockaddr_nl</a> *dst;
<span class="keyword">struct </span>ucred *creds;
<span class="keyword">struct </span>msghdr hdr = {
.msg_name = (<span class="keywordtype">void</span> *) &handle->h_peer,
.msg_namelen = <span class="keyword">sizeof</span>(<span class="keyword">struct</span> <a class="code" href="structsockaddr__nl.html" title="Netlink socket address.">sockaddr_nl</a>),
};
<span class="comment">/* Overwrite destination if specified in the message itself, defaults</span>
<span class="comment"> * to the peer address of the handle.</span>
<span class="comment"> */</span>
dst = nlmsg_get_dst(msg);
<span class="keywordflow">if</span> (dst-><a class="code" href="structsockaddr__nl.html#a28df558ea904fe04840eb2a4ce4b779d" title="socket family (AF_NETLINK)">nl_family</a> == AF_NETLINK)
hdr.msg_name = dst;
<span class="comment">/* Add credentials if present. */</span>
creds = nlmsg_get_creds(msg);
<span class="keywordflow">if</span> (creds != NULL) {
<span class="keywordtype">char</span> buf[CMSG_SPACE(<span class="keyword">sizeof</span>(<span class="keyword">struct</span> ucred))];
<span class="keyword">struct </span>cmsghdr *cmsg;
hdr.msg_control = buf;
hdr.msg_controllen = <span class="keyword">sizeof</span>(buf);
cmsg = CMSG_FIRSTHDR(&hdr);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_CREDENTIALS;
cmsg->cmsg_len = CMSG_LEN(<span class="keyword">sizeof</span>(<span class="keyword">struct</span> ucred));
memcpy(CMSG_DATA(cmsg), creds, <span class="keyword">sizeof</span>(<span class="keyword">struct</span> ucred));
}
<span class="keywordflow">return</span> <a class="code" href="group__nl.html#gaf3dca993337ed2d60a42269eaab65585" title="Send netlink message with control over sendmsg() message header.">nl_sendmsg</a>(handle, msg, &hdr);
}
</pre></div>
</div>
</div>
<a class="anchor" id="ga01a2aad82350f867e704d5c696438b60"></a><!-- doxytag: member="nl.c::nl_send_auto_complete" ref="ga01a2aad82350f867e704d5c696438b60" args="(struct nl_handle *handle, struct nl_msg *msg)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_send_auto_complete </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">struct nl_msg * </td>
<td class="paramname"><em>msg</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle. </td></tr>
<tr><td class="paramname">msg</td><td>Netlink message to be sent.</td></tr>
</table>
</dd>
</dl>
<p>Checks the netlink message <code>nlh</code> for completness and extends it as required before sending it out. Checked fields include pid, sequence nr, and flags.</p>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="group__nl.html#ga5f3fff85c39f18946100c85f09d2c41c" title="Send netlink message.">nl_send()</a> </dd></dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>Number of characters sent or a negative error code. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00373">373</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>References <a class="el" href="nl_8c_source.html#l00325">nl_send()</a>, <a class="el" href="netlink-kernel_8h_source.html#l00076">NLM_F_ACK</a>, <a class="el" href="netlink-kernel_8h_source.html#l00065">NLM_F_REQUEST</a>, <a class="el" href="netlink-kernel_8h_source.html#l00042">nlmsghdr::nlmsg_flags</a>, <a class="el" href="msg_8c_source.html#l00643">nlmsg_hdr()</a>, <a class="el" href="netlink-kernel_8h_source.html#l00052">nlmsghdr::nlmsg_pid</a>, and <a class="el" href="netlink-kernel_8h_source.html#l00047">nlmsghdr::nlmsg_seq</a>.</p>
<p>Referenced by <a class="el" href="lookup_8c_source.html#l00263">flnl_lookup()</a>, <a class="el" href="nl_8c_source.html#l00410">nl_send_simple()</a>, <a class="el" href="route_2addr_8c_source.html#l00765">rtnl_addr_add()</a>, <a class="el" href="route_2addr_8c_source.html#l00838">rtnl_addr_delete()</a>, <a class="el" href="class_8c_source.html#l00148">rtnl_class_add()</a>, <a class="el" href="classifier_8c_source.html#l00162">rtnl_cls_add()</a>, <a class="el" href="classifier_8c_source.html#l00208">rtnl_cls_change()</a>, <a class="el" href="classifier_8c_source.html#l00256">rtnl_cls_delete()</a>, <a class="el" href="link_8c_source.html#l01048">rtnl_link_change()</a>, <a class="el" href="neigh_8c_source.html#l00656">rtnl_neigh_add()</a>, <a class="el" href="neigh_8c_source.html#l00770">rtnl_neigh_change()</a>, <a class="el" href="neigh_8c_source.html#l00711">rtnl_neigh_delete()</a>, <a class="el" href="neightbl_8c_source.html#l00578">rtnl_neightbl_change()</a>, <a class="el" href="qdisc_8c_source.html#l00224">rtnl_qdisc_add()</a>, <a class="el" href="qdisc_8c_source.html#l00279">rtnl_qdisc_change()</a>, <a class="el" href="qdisc_8c_source.html#l00348">rtnl_qdisc_delete()</a>, <a class="el" href="rule_8c_source.html#l00581">rtnl_rule_add()</a>, and <a class="el" href="rule_8c_source.html#l00635">rtnl_rule_delete()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keyword">struct </span><a class="code" href="structnlmsghdr.html" title="Netlink message header.">nlmsghdr</a> *nlh;
<span class="keyword">struct </span>nl_cb *cb = handle->h_cb;
nlh = <a class="code" href="group__msg.html#gaa5f29579d86d2bdab26c312b44b56de7" title="Return actual netlink message.">nlmsg_hdr</a>(msg);
<span class="keywordflow">if</span> (nlh-><a class="code" href="structnlmsghdr.html#a071903f5e2400298bca69ac70500421f" title="Netlink PID of the proccess sending the message.">nlmsg_pid</a> == 0)
nlh-><a class="code" href="structnlmsghdr.html#a071903f5e2400298bca69ac70500421f" title="Netlink PID of the proccess sending the message.">nlmsg_pid</a> = handle->h_local.nl_pid;
<span class="keywordflow">if</span> (nlh-><a class="code" href="structnlmsghdr.html#ad6c6a7aa9de65bb2da498c84148be7e6" title="Sequence number.">nlmsg_seq</a> == 0)
nlh-><a class="code" href="structnlmsghdr.html#ad6c6a7aa9de65bb2da498c84148be7e6" title="Sequence number.">nlmsg_seq</a> = handle->h_seq_next++;
<span class="keywordflow">if</span> (msg->nm_protocol == -1)
msg->nm_protocol = handle->h_proto;
nlh-><a class="code" href="structnlmsghdr.html#abcf664d354ea35ebb9b3d8a50088fec6" title="Message flags.">nlmsg_flags</a> |= (<a class="code" href="group__msg.html#ga456954d27b8adedd78136a9511f13160" title="Must be set on all request messages (typically from user space to kernel space).">NLM_F_REQUEST</a> | <a class="code" href="group__msg.html#ga67d5b6ba8714b97d74df72d119351bee" title="Request for an acknowledgment on success.">NLM_F_ACK</a>);
<span class="keywordflow">if</span> (cb->cb_send_ow)
<span class="keywordflow">return</span> cb->cb_send_ow(handle, msg);
<span class="keywordflow">else</span>
<span class="keywordflow">return</span> <a class="code" href="group__nl.html#ga5f3fff85c39f18946100c85f09d2c41c" title="Send netlink message.">nl_send</a>(handle, msg);
}
</pre></div>
</div>
</div>
<a class="anchor" id="ga73ed88a505f2d67bcf328183fe1e692a"></a><!-- doxytag: member="nl.c::nl_send_simple" ref="ga73ed88a505f2d67bcf328183fe1e692a" args="(struct nl_handle *handle, int type, int flags, void *buf, size_t size)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_send_simple </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int </td>
<td class="paramname"><em>type</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">int </td>
<td class="paramname"><em>flags</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">void * </td>
<td class="paramname"><em>buf</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t </td>
<td class="paramname"><em>size</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle. </td></tr>
<tr><td class="paramname">type</td><td>Netlink message type. </td></tr>
<tr><td class="paramname">flags</td><td>Netlink message flags. </td></tr>
<tr><td class="paramname">buf</td><td>Data buffer. </td></tr>
<tr><td class="paramname">size</td><td>Size of data buffer.</td></tr>
</table>
</dd>
</dl>
<p>Builds a netlink message with the specified type and flags and appends the specified data as payload to the message.</p>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="group__nl.html#ga01a2aad82350f867e704d5c696438b60" title="Send netlink message and check & extend header values as needed.">nl_send_auto_complete()</a> </dd></dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>Number of characters sent on success or a negative error code. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00410">410</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>References <a class="el" href="nl_8c_source.html#l00373">nl_send_auto_complete()</a>, <a class="el" href="msg_8c_source.html#l00448">nlmsg_alloc_simple()</a>, <a class="el" href="msg_8c_source.html#l00549">nlmsg_append()</a>, and <a class="el" href="msg_8c_source.html#l00656">nlmsg_free()</a>.</p>
<p>Referenced by <a class="el" href="genl_8c_source.html#l00128">genl_send_simple()</a>, <a class="el" href="nfnl_8c_source.html#l00108">nfnl_send_simple()</a>, and <a class="el" href="rtnl_8c_source.html#l00040">nl_rtgen_request()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordtype">int</span> err;
<span class="keyword">struct </span>nl_msg *msg;
msg = <a class="code" href="group__msg.html#ga580d8697d19050c55060bc10ab4eae9f" title="Allocate a new netlink message.">nlmsg_alloc_simple</a>(type, flags);
<span class="keywordflow">if</span> (!msg)
<span class="keywordflow">return</span> nl_errno(ENOMEM);
<span class="keywordflow">if</span> (buf && size) {
err = <a class="code" href="group__msg.html#gacc5e5ade5675d041f86c7c8693f7088d" title="Append data to tail of a netlink message.">nlmsg_append</a>(msg, buf, size, NLMSG_ALIGNTO);
<span class="keywordflow">if</span> (err < 0)
<span class="keywordflow">goto</span> errout;
}
err = <a class="code" href="group__nl.html#ga01a2aad82350f867e704d5c696438b60" title="Send netlink message and check &amp; extend header values as needed.">nl_send_auto_complete</a>(handle, msg);
errout:
<a class="code" href="group__msg.html#ga138ba9bee70553f9fbe7143deacad48c" title="Free a netlink message.">nlmsg_free</a>(msg);
<span class="keywordflow">return</span> err;
}
</pre></div>
</div>
</div>
<a class="anchor" id="ga060acc8371fdb242c5ae3d5b761d28e1"></a><!-- doxytag: member="nl.c::nl_recv" ref="ga060acc8371fdb242c5ae3d5b761d28e1" args="(struct nl_handle *handle, struct sockaddr_nl *nla, unsigned char **buf, struct ucred **creds)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_recv </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">struct <a class="el" href="structsockaddr__nl.html">sockaddr_nl</a> * </td>
<td class="paramname"><em>nla</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">unsigned char ** </td>
<td class="paramname"><em>buf</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">struct ucred ** </td>
<td class="paramname"><em>creds</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>Netlink handle. </td></tr>
<tr><td class="paramname">nla</td><td>Destination pointer for peer's netlink address. </td></tr>
<tr><td class="paramname">buf</td><td>Destination pointer for message content. </td></tr>
<tr><td class="paramname">creds</td><td>Destination pointer for credentials.</td></tr>
</table>
</dd>
</dl>
<p>Receives a netlink message, allocates a buffer in <code>*buf</code> and stores the message content. The peer's netlink address is stored in <code>*nla</code>. The caller is responsible for freeing the buffer allocated in <code>*buf</code> if a positive value is returned. Interruped system calls are handled by repeating the read. The input buffer size is determined by peeking before the actual read is done.</p>
<p>A non-blocking sockets causes the function to return immediately with a return value of 0 if no data is available.</p>
<dl class="return"><dt><b>Returns:</b></dt><dd>Number of octets read, 0 on EOF or a negative error code. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00460">460</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordtype">int</span> n;
<span class="keywordtype">int</span> flags = 0;
<span class="keyword">static</span> <span class="keywordtype">int</span> page_size = 0;
<span class="keyword">struct </span>iovec iov;
<span class="keyword">struct </span>msghdr msg = {
.msg_name = (<span class="keywordtype">void</span> *) nla,
.msg_namelen = <span class="keyword">sizeof</span>(<span class="keyword">struct</span> <a class="code" href="structsockaddr__nl.html" title="Netlink socket address.">sockaddr_nl</a>),
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_control = NULL,
.msg_controllen = 0,
.msg_flags = 0,
};
<span class="keyword">struct </span>cmsghdr *cmsg;
<span class="keywordflow">if</span> (handle->h_flags & NL_MSG_PEEK)
flags |= MSG_PEEK;
<span class="keywordflow">if</span> (page_size == 0)
page_size = getpagesize();
iov.iov_len = page_size;
iov.iov_base = *buf = calloc(1, iov.iov_len);
<span class="keywordflow">if</span> (handle->h_flags & NL_SOCK_PASSCRED) {
msg.msg_controllen = CMSG_SPACE(<span class="keyword">sizeof</span>(<span class="keyword">struct</span> ucred));
msg.msg_control = calloc(1, msg.msg_controllen);
}
retry:
n = recvmsg(handle->h_fd, &msg, flags);
<span class="keywordflow">if</span> (!n)
<span class="keywordflow">goto</span> abort;
<span class="keywordflow">else</span> <span class="keywordflow">if</span> (n < 0) {
<span class="keywordflow">if</span> (errno == EINTR) {
NL_DBG(3, <span class="stringliteral">"recvmsg() returned EINTR, retrying\n"</span>);
<span class="keywordflow">goto</span> retry;
} <span class="keywordflow">else</span> <span class="keywordflow">if</span> (errno == EAGAIN) {
NL_DBG(3, <span class="stringliteral">"recvmsg() returned EAGAIN, aborting\n"</span>);
<span class="keywordflow">goto</span> abort;
} <span class="keywordflow">else</span> {
free(msg.msg_control);
free(*buf);
<span class="keywordflow">return</span> nl_error(errno, <span class="stringliteral">"recvmsg failed"</span>);
}
}
<span class="keywordflow">if</span> (iov.iov_len < n ||
msg.msg_flags & MSG_TRUNC) {
<span class="comment">/* Provided buffer is not long enough, enlarge it</span>
<span class="comment"> * and try again. */</span>
iov.iov_len *= 2;
iov.iov_base = *buf = realloc(*buf, iov.iov_len);
<span class="keywordflow">goto</span> retry;
} <span class="keywordflow">else</span> <span class="keywordflow">if</span> (msg.msg_flags & MSG_CTRUNC) {
msg.msg_controllen *= 2;
msg.msg_control = realloc(msg.msg_control, msg.msg_controllen);
<span class="keywordflow">goto</span> retry;
} <span class="keywordflow">else</span> <span class="keywordflow">if</span> (flags != 0) {
<span class="comment">/* Buffer is big enough, do the actual reading */</span>
flags = 0;
<span class="keywordflow">goto</span> retry;
}
<span class="keywordflow">if</span> (msg.msg_namelen != <span class="keyword">sizeof</span>(<span class="keyword">struct</span> <a class="code" href="structsockaddr__nl.html" title="Netlink socket address.">sockaddr_nl</a>)) {
free(msg.msg_control);
free(*buf);
<span class="keywordflow">return</span> nl_error(EADDRNOTAVAIL, <span class="stringliteral">"socket address size mismatch"</span>);
}
<span class="keywordflow">for</span> (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
<span class="keywordflow">if</span> (cmsg->cmsg_level == SOL_SOCKET &&
cmsg->cmsg_type == SCM_CREDENTIALS) {
*creds = calloc(1, <span class="keyword">sizeof</span>(<span class="keyword">struct</span> ucred));
memcpy(*creds, CMSG_DATA(cmsg), <span class="keyword">sizeof</span>(<span class="keyword">struct</span> ucred));
<span class="keywordflow">break</span>;
}
}
free(msg.msg_control);
<span class="keywordflow">return</span> n;
abort:
free(msg.msg_control);
free(*buf);
<span class="keywordflow">return</span> 0;
}
</pre></div>
</div>
</div>
<a class="anchor" id="ga1bb066e1772b89f79fe1d76a4ef243a6"></a><!-- doxytag: member="nl.c::nl_recvmsgs" ref="ga1bb066e1772b89f79fe1d76a4ef243a6" args="(struct nl_handle *handle, struct nl_cb *cb)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_recvmsgs </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">struct nl_cb * </td>
<td class="paramname"><em>cb</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>netlink handle </td></tr>
<tr><td class="paramname">cb</td><td>set of callbacks to control behaviour.</td></tr>
</table>
</dd>
</dl>
<p>Repeatedly calls <a class="el" href="group__nl.html#ga060acc8371fdb242c5ae3d5b761d28e1" title="Receive data from netlink socket.">nl_recv()</a> or the respective replacement if provided by the application (see <a class="el" href="group__cb.html#ga0d2f92ed95a6d7a5f915e128d1643e24" title="Overwrite internal calls to nl_recv()">nl_cb_overwrite_recv()</a>) and parses the received data as netlink messages. Stops reading if one of the callbacks returns NL_STOP or nl_recv returns either 0 or a negative error code.</p>
<p>A non-blocking sockets causes the function to return immediately if no data is available.</p>
<dl class="return"><dt><b>Returns:</b></dt><dd>0 on success or a negative error code from <a class="el" href="group__nl.html#ga060acc8371fdb242c5ae3d5b761d28e1" title="Receive data from netlink socket.">nl_recv()</a>. </dd></dl>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00767">767</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>Referenced by <a class="el" href="nl_8c_source.html#l00781">nl_recvmsgs_default()</a>, and <a class="el" href="nl_8c_source.html#l00800">nl_wait_for_ack()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordflow">if</span> (cb->cb_recvmsgs_ow)
<span class="keywordflow">return</span> cb->cb_recvmsgs_ow(handle, cb);
<span class="keywordflow">else</span>
<span class="keywordflow">return</span> recvmsgs(handle, cb);
}
</pre></div>
</div>
</div>
<a class="anchor" id="gab287fc77c46d80c4e22bc87494cbf853"></a><!-- doxytag: member="nl.c::nl_recvmsgs_default" ref="gab287fc77c46d80c4e22bc87494cbf853" args="(struct nl_handle *handle)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_recvmsgs_default </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em></td><td>)</td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>netlink handle</td></tr>
</table>
</dd>
</dl>
<p>Calls <a class="el" href="group__nl.html#ga1bb066e1772b89f79fe1d76a4ef243a6" title="Receive a set of messages from a netlink socket.">nl_recvmsgs()</a> with the handlers configured in the netlink handle. </p>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00781">781</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>References <a class="el" href="nl_8c_source.html#l00767">nl_recvmsgs()</a>.</p>
<p>Referenced by <a class="el" href="cache__mngr_8c_source.html#l00356">nl_cache_mngr_data_ready()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordflow">return</span> <a class="code" href="group__nl.html#ga1bb066e1772b89f79fe1d76a4ef243a6" title="Receive a set of messages from a netlink socket.">nl_recvmsgs</a>(handle, handle->h_cb);
}
</pre></div>
</div>
</div>
<a class="anchor" id="gaa65fec588e0a0a2de1881fb8366ccd79"></a><!-- doxytag: member="nl.c::nl_wait_for_ack" ref="gaa65fec588e0a0a2de1881fb8366ccd79" args="(struct nl_handle *handle)" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int nl_wait_for_ack </td>
<td>(</td>
<td class="paramtype">struct nl_handle * </td>
<td class="paramname"><em>handle</em></td><td>)</td>
<td></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramname">handle</td><td>netlink handle </td></tr>
</table>
</dd>
</dl>
<dl class="pre"><dt><b>Precondition:</b></dt><dd>The netlink socket must be in blocking state.</dd></dl>
<p>Waits until an ACK is received for the latest not yet acknowledged netlink message. </p>
<p>Definition at line <a class="el" href="nl_8c_source.html#l00800">800</a> of file <a class="el" href="nl_8c_source.html">nl.c</a>.</p>
<p>References <a class="el" href="handlers_8h_source.html#l00103">NL_CB_ACK</a>, <a class="el" href="handlers_8c_source.html#l00285">nl_cb_clone()</a>, <a class="el" href="handlers_8h_source.html#l00083">NL_CB_CUSTOM</a>, <a class="el" href="handlers_8c_source.html#l00337">nl_cb_set()</a>, and <a class="el" href="nl_8c_source.html#l00767">nl_recvmsgs()</a>.</p>
<p>Referenced by <a class="el" href="route_2addr_8c_source.html#l00765">rtnl_addr_add()</a>, <a class="el" href="route_2addr_8c_source.html#l00838">rtnl_addr_delete()</a>, <a class="el" href="class_8c_source.html#l00148">rtnl_class_add()</a>, <a class="el" href="classifier_8c_source.html#l00162">rtnl_cls_add()</a>, <a class="el" href="classifier_8c_source.html#l00208">rtnl_cls_change()</a>, <a class="el" href="classifier_8c_source.html#l00256">rtnl_cls_delete()</a>, <a class="el" href="link_8c_source.html#l01048">rtnl_link_change()</a>, <a class="el" href="neigh_8c_source.html#l00656">rtnl_neigh_add()</a>, <a class="el" href="neigh_8c_source.html#l00770">rtnl_neigh_change()</a>, <a class="el" href="neigh_8c_source.html#l00711">rtnl_neigh_delete()</a>, <a class="el" href="neightbl_8c_source.html#l00578">rtnl_neightbl_change()</a>, <a class="el" href="qdisc_8c_source.html#l00224">rtnl_qdisc_add()</a>, <a class="el" href="qdisc_8c_source.html#l00279">rtnl_qdisc_change()</a>, <a class="el" href="qdisc_8c_source.html#l00348">rtnl_qdisc_delete()</a>, <a class="el" href="rule_8c_source.html#l00581">rtnl_rule_add()</a>, and <a class="el" href="rule_8c_source.html#l00635">rtnl_rule_delete()</a>.</p>
<div class="fragment"><pre class="fragment">{
<span class="keywordtype">int</span> err;
<span class="keyword">struct </span>nl_cb *cb;
cb = <a class="code" href="group__cb.html#gad438f32bb0f83bd1d15f53e9525f1f65" title="Clone an existing callback handle.">nl_cb_clone</a>(handle->h_cb);
<span class="keywordflow">if</span> (cb == NULL)
<span class="keywordflow">return</span> nl_get_errno();
<a class="code" href="group__cb.html#gabe7b2516f28fbb8bb9c5b1ea2dfaf1d3" title="Set up a callback.">nl_cb_set</a>(cb, <a class="code" href="group__cb.html#gga3f60f4515ada826d2bf16395ee722363a8295b387c07bd076ccdee45b555f1134" title="Message is an acknowledge.">NL_CB_ACK</a>, <a class="code" href="group__cb.html#ggaba3fabad0c62db483941101e1a18d14da22448271a402b4c4a55733ef4884c038" title="Customized handler specified by the user.">NL_CB_CUSTOM</a>, ack_wait_handler, NULL);
err = <a class="code" href="group__nl.html#ga1bb066e1772b89f79fe1d76a4ef243a6" title="Receive a set of messages from a netlink socket.">nl_recvmsgs</a>(handle, cb);
nl_cb_put(cb);
<span class="keywordflow">return</span> err;
}
</pre></div>
</div>
</div>
</div>
<hr class="footer"/><address class="footer"><small>Generated on Mon Mar 21 2011 for libnl by 
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.7.3 </small></address>
</body>
</html>
distrib
>
Fedora
>
14
>
x86_64
>
media
>
updates
>
by-pkgid
>
87b89b73c41f4440bb86afd421c7548f
>
files
>
152
