xref: /freebsd/lib/libnetgraph/sock.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
1 /*
2  * sock.c
3  *
4  * Copyright (c) 1996-1999 Whistle Communications, Inc.
5  * All rights reserved.
6  *
7  * Subject to the following obligations and disclaimer of warranty, use and
8  * redistribution of this software, in source or object code forms, with or
9  * without modifications are expressly permitted by Whistle Communications;
10  * provided, however, that:
11  * 1. Any and all reproductions of the source or object code must include the
12  *    copyright notice above and the following disclaimer of warranties; and
13  * 2. No rights are granted, in any manner or form, to use Whistle
14  *    Communications, Inc. trademarks, including the mark "WHISTLE
15  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
16  *    such appears in the above copyright notice or in the software.
17  *
18  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
19  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
20  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
21  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
22  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
23  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
24  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
25  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
26  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
27  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
28  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
29  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
30  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
31  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
34  * OF SUCH DAMAGE.
35  *
36  * Author: Archie Cobbs <archie@whistle.com>
37  *
38  * $Whistle: sock.c,v 1.12 1999/01/20 00:57:23 archie Exp $
39  */
40 
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <sys/types.h>
45 #include <sys/socket.h>
46 #include <stdarg.h>
47 #include <netgraph/ng_message.h>
48 #include <netgraph/ng_socket.h>
49 
50 #include "netgraph.h"
51 #include "internal.h"
52 
53 /* The socket node type KLD */
54 #define NG_SOCKET_KLD	"ng_socket.ko"
55 
56 /*
57  * Create a socket type node and give it the supplied name.
58  * Return data and control sockets corresponding to the node.
59  * Returns -1 if error and sets errno.
60  */
61 int
62 NgMkSockNode(const char *name, int *csp, int *dsp)
63 {
64 	char namebuf[NG_NODESIZ];
65 	int cs = -1;		/* control socket */
66 	int ds = -1;		/* data socket */
67 	int errnosv;
68 
69 	/* Empty name means no name */
70 	if (name && *name == 0)
71 		name = NULL;
72 
73 	/* Create control socket; this also creates the netgraph node.
74 	   If we get an EPROTONOSUPPORT then the socket node type is
75 	   not loaded, so load it and try again. */
76 	if ((cs = socket(AF_NETGRAPH, SOCK_DGRAM, NG_CONTROL)) < 0) {
77 		if (errno == EPROTONOSUPPORT) {
78 			if (kldload(NG_SOCKET_KLD) < 0) {
79 				errnosv = errno;
80 				if (_gNgDebugLevel >= 1)
81 					NGLOG("can't load %s", NG_SOCKET_KLD);
82 				goto errout;
83 			}
84 			cs = socket(AF_NETGRAPH, SOCK_DGRAM, NG_CONTROL);
85 			if (cs >= 0)
86 				goto gotNode;
87 		}
88 		errnosv = errno;
89 		if (_gNgDebugLevel >= 1)
90 			NGLOG("socket");
91 		goto errout;
92 	}
93 
94 gotNode:
95 	/* Assign the node the desired name, if any */
96 	if (name != NULL) {
97 		u_char sbuf[NG_NODESIZ + NGSA_OVERHEAD];
98 		struct sockaddr_ng *const sg = (struct sockaddr_ng *) sbuf;
99 
100 		/* Assign name */
101 		strlcpy(sg->sg_data, name, NG_NODESIZ);
102 		sg->sg_family = AF_NETGRAPH;
103 		sg->sg_len = strlen(sg->sg_data) + 1 + NGSA_OVERHEAD;
104 		if (bind(cs, (struct sockaddr *) sg, sg->sg_len) < 0) {
105 			errnosv = errno;
106 			if (_gNgDebugLevel >= 1)
107 				NGLOG("bind(%s)", sg->sg_data);
108 			goto errout;
109 		}
110 
111 		/* Save node name */
112 		strlcpy(namebuf, name, sizeof(namebuf));
113 	} else if (dsp != NULL) {
114 		u_char rbuf[sizeof(struct ng_mesg) + sizeof(struct nodeinfo)];
115 		struct ng_mesg *const resp = (struct ng_mesg *) rbuf;
116 		struct nodeinfo *const ni = (struct nodeinfo *) resp->data;
117 
118 		/* Find out the node ID */
119 		if (NgSendMsg(cs, ".", NGM_GENERIC_COOKIE,
120 		    NGM_NODEINFO, NULL, 0) < 0) {
121 			errnosv = errno;
122 			if (_gNgDebugLevel >= 1)
123 				NGLOG("send nodeinfo");
124 			goto errout;
125 		}
126 		if (NgRecvMsg(cs, resp, sizeof(rbuf), NULL) < 0) {
127 			errnosv = errno;
128 			if (_gNgDebugLevel >= 1)
129 				NGLOG("recv nodeinfo");
130 			goto errout;
131 		}
132 
133 		/* Save node "name" */
134 		snprintf(namebuf, sizeof(namebuf), "[%lx]", (u_long) ni->id);
135 	}
136 
137 	/* Create data socket if desired */
138 	if (dsp != NULL) {
139 		u_char sbuf[NG_NODESIZ + 1 + NGSA_OVERHEAD];
140 		struct sockaddr_ng *const sg = (struct sockaddr_ng *) sbuf;
141 
142 		/* Create data socket, initially just "floating" */
143 		if ((ds = socket(AF_NETGRAPH, SOCK_DGRAM, NG_DATA)) < 0) {
144 			errnosv = errno;
145 			if (_gNgDebugLevel >= 1)
146 				NGLOG("socket");
147 			goto errout;
148 		}
149 
150 		/* Associate the data socket with the node */
151 		snprintf(sg->sg_data, NG_NODESIZ + 1, "%s:", namebuf);
152 		sg->sg_family = AF_NETGRAPH;
153 		sg->sg_len = strlen(sg->sg_data) + 1 + NGSA_OVERHEAD;
154 		if (connect(ds, (struct sockaddr *) sg, sg->sg_len) < 0) {
155 			errnosv = errno;
156 			if (_gNgDebugLevel >= 1)
157 				NGLOG("connect(%s)", sg->sg_data);
158 			goto errout;
159 		}
160 	}
161 
162 	/* Return the socket(s) */
163 	if (csp)
164 		*csp = cs;
165 	else
166 		close(cs);
167 	if (dsp)
168 		*dsp = ds;
169 	return (0);
170 
171 errout:
172 	/* Failed */
173 	if (cs >= 0)
174 		close(cs);
175 	if (ds >= 0)
176 		close(ds);
177 	errno = errnosv;
178 	return (-1);
179 }
180 
181 /*
182  * Assign a globally unique name to a node
183  * Returns -1 if error and sets errno.
184  */
185 int
186 NgNameNode(int cs, const char *path, const char *fmt, ...)
187 {
188 	struct ngm_name ngn;
189 	va_list args;
190 
191 	/* Build message arg */
192 	va_start(args, fmt);
193 	vsnprintf(ngn.name, sizeof(ngn.name), fmt, args);
194 	va_end(args);
195 
196 	/* Send message */
197 	if (NgSendMsg(cs, path,
198 	    NGM_GENERIC_COOKIE, NGM_NAME, &ngn, sizeof(ngn)) < 0) {
199 		if (_gNgDebugLevel >= 1)
200 			NGLOGX("%s: failed", __func__);
201 		return (-1);
202 	}
203 
204 	/* Done */
205 	return (0);
206 }
207 
208 /*
209  * Read a packet from a data socket
210  * Returns -1 if error and sets errno.
211  */
212 int
213 NgRecvData(int ds, u_char * buf, size_t len, char *hook)
214 {
215 	u_char frombuf[NG_HOOKSIZ + NGSA_OVERHEAD];
216 	struct sockaddr_ng *const from = (struct sockaddr_ng *) frombuf;
217 	socklen_t fromlen = sizeof(frombuf);
218 	int rtn, errnosv;
219 
220 	/* Read packet */
221 	rtn = recvfrom(ds, buf, len, 0, (struct sockaddr *) from, &fromlen);
222 	if (rtn < 0) {
223 		errnosv = errno;
224 		if (_gNgDebugLevel >= 1)
225 			NGLOG("recvfrom");
226 		errno = errnosv;
227 		return (-1);
228 	}
229 
230 	/* Copy hook name */
231 	if (hook != NULL)
232 		strlcpy(hook, from->sg_data, NG_HOOKSIZ);
233 
234 	/* Debugging */
235 	if (_gNgDebugLevel >= 2) {
236 		NGLOGX("READ %s from hook \"%s\" (%d bytes)",
237 		       rtn ? "PACKET" : "EOF", from->sg_data, rtn);
238 		if (_gNgDebugLevel >= 3)
239 			_NgDebugBytes(buf, rtn);
240 	}
241 
242 	/* Done */
243 	return (rtn);
244 }
245 
246 /*
247  * Identical to NgRecvData() except buffer is dynamically allocated.
248  */
249 int
250 NgAllocRecvData(int ds, u_char **buf, char *hook)
251 {
252 	int len;
253 	socklen_t optlen;
254 
255 	optlen = sizeof(len);
256 	if (getsockopt(ds, SOL_SOCKET, SO_RCVBUF, &len, &optlen) == -1 ||
257 	    (*buf = malloc(len)) == NULL)
258 		return (-1);
259 	if ((len = NgRecvData(ds, *buf, len, hook)) < 0)
260 		free(*buf);
261 	return (len);
262 }
263 
264 /*
265  * Write a packet to a data socket. The packet will be sent
266  * out the corresponding node on the specified hook.
267  * Returns -1 if error and sets errno.
268  */
269 int
270 NgSendData(int ds, const char *hook, const u_char * buf, size_t len)
271 {
272 	u_char sgbuf[NG_HOOKSIZ + NGSA_OVERHEAD];
273 	struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf;
274 	int errnosv;
275 
276 	/* Set up destination hook */
277 	sg->sg_family = AF_NETGRAPH;
278 	strlcpy(sg->sg_data, hook, NG_HOOKSIZ);
279 	sg->sg_len = strlen(sg->sg_data) + 1 + NGSA_OVERHEAD;
280 
281 	/* Debugging */
282 	if (_gNgDebugLevel >= 2) {
283 		NGLOGX("WRITE PACKET to hook \"%s\" (%d bytes)", hook, len);
284 		_NgDebugSockaddr(sg);
285 		if (_gNgDebugLevel >= 3)
286 			_NgDebugBytes(buf, len);
287 	}
288 
289 	/* Send packet */
290 	if (sendto(ds, buf, len, 0, (struct sockaddr *) sg, sg->sg_len) < 0) {
291 		errnosv = errno;
292 		if (_gNgDebugLevel >= 1)
293 			NGLOG("sendto(%s)", sg->sg_data);
294 		errno = errnosv;
295 		return (-1);
296 	}
297 
298 	/* Done */
299 	return (0);
300 }
301 
302