1 /*
2 * msg.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 * $FreeBSD: src/lib/libnetgraph/msg.c,v 1.14 2007/05/14 14:18:41 mav Exp $
39 * $DragonFly: src/lib/libnetgraph/msg.c,v 1.4 2007/06/03 23:41:25 swildner Exp $
40 * $Whistle: msg.c,v 1.9 1999/01/20 00:57:23 archie Exp $
41 */
42
43 #include <sys/types.h>
44 #include <sys/socket.h>
45 #include <stdarg.h>
46 #include <netgraph7/ng_message.h>
47 #include <netgraph7/socket/ng_socket.h>
48
49 #include "netgraph.h"
50 #include "internal.h"
51
52 /* Next message token value */
53 static int gMsgId;
54
55 /* For delivering both messages and replies */
56 static int NgDeliverMsg(int cs, const char *path,
57 const struct ng_mesg *hdr, const void *args, size_t arglen);
58
59 /*
60 * Send a message to a node using control socket node "cs".
61 * Returns -1 if error and sets errno appropriately.
62 * If successful, returns the message ID (token) used.
63 */
64 int
NgSendMsg(int cs,const char * path,int cookie,int cmd,const void * args,size_t arglen)65 NgSendMsg(int cs, const char *path,
66 int cookie, int cmd, const void *args, size_t arglen)
67 {
68 struct ng_mesg msg;
69
70 /* Prepare message header */
71 memset(&msg, 0, sizeof(msg));
72 msg.header.version = NG_VERSION;
73 msg.header.typecookie = cookie;
74 if (++gMsgId < 0)
75 gMsgId = 1;
76 msg.header.token = gMsgId;
77 msg.header.flags = NGF_ORIG;
78 msg.header.cmd = cmd;
79 snprintf((char *)msg.header.cmdstr, NG_CMDSTRSIZ, "cmd%d", cmd);
80
81 /* Deliver message */
82 if (NgDeliverMsg(cs, path, &msg, args, arglen) < 0)
83 return (-1);
84 return (msg.header.token);
85 }
86
87 /*
88 * Send a message given in ASCII format. We first ask the node to translate
89 * the command into binary, and then we send the binary.
90 */
91 int
NgSendAsciiMsg(int cs,const char * path,const char * fmt,...)92 NgSendAsciiMsg(int cs, const char *path, const char *fmt, ...)
93 {
94 struct ng_mesg *reply, *binary, *ascii;
95 char *buf, *cmd, *args;
96 va_list fmtargs;
97 int token;
98
99 /* Parse out command and arguments */
100 va_start(fmtargs, fmt);
101 vasprintf(&buf, fmt, fmtargs);
102 va_end(fmtargs);
103 if (buf == NULL)
104 return (-1);
105
106 /* Parse out command, arguments */
107 for (cmd = buf; isspace(*cmd); cmd++)
108 ;
109 for (args = cmd; *args != '\0' && !isspace(*args); args++)
110 ;
111 if (*args != '\0') {
112 while (isspace(*args))
113 *args++ = '\0';
114 }
115
116 /* Get a bigger buffer to hold inner message header plus arg string */
117 if ((ascii = malloc(sizeof(struct ng_mesg)
118 + strlen(args) + 1)) == NULL) {
119 free(buf);
120 return (-1);
121 }
122 memset(ascii, 0, sizeof(*ascii));
123
124 /* Build inner header (only need cmdstr, arglen, and data fields) */
125 strncpy((char *)ascii->header.cmdstr, cmd,
126 sizeof(ascii->header.cmdstr) - 1);
127 strcpy(ascii->data, args);
128 ascii->header.arglen = strlen(ascii->data) + 1;
129 free(buf);
130
131 /* Send node a request to convert ASCII to binary */
132 if (NgSendMsg(cs, path, NGM_GENERIC_COOKIE, NGM_ASCII2BINARY,
133 (u_char *)ascii, sizeof(*ascii) + ascii->header.arglen) < 0) {
134 free(ascii);
135 return (-1);
136 }
137 free(ascii);
138
139 /* Get reply */
140 if (NgAllocRecvMsg(cs, &reply, NULL) < 0)
141 return (-1);
142
143 /* Now send binary version */
144 binary = (struct ng_mesg *)reply->data;
145 if (++gMsgId < 0)
146 gMsgId = 1;
147 binary->header.token = gMsgId;
148 binary->header.version = NG_VERSION;
149 if (NgDeliverMsg(cs,
150 path, binary, binary->data, binary->header.arglen) < 0) {
151 free(reply);
152 return (-1);
153 }
154 token = binary->header.token;
155 free(reply);
156 return (token);
157 }
158
159 /*
160 * Send a message that is a reply to a previously received message.
161 * Returns -1 and sets errno on error, otherwise returns zero.
162 */
163 int
NgSendReplyMsg(int cs,const char * path,const struct ng_mesg * msg,const void * args,size_t arglen)164 NgSendReplyMsg(int cs, const char *path,
165 const struct ng_mesg *msg, const void *args, size_t arglen)
166 {
167 struct ng_mesg rep;
168
169 /* Prepare message header */
170 rep = *msg;
171 rep.header.flags = NGF_RESP;
172
173 /* Deliver message */
174 return (NgDeliverMsg(cs, path, &rep, args, arglen));
175 }
176
177 /*
178 * Send a message to a node using control socket node "cs".
179 * Returns -1 if error and sets errno appropriately, otherwise zero.
180 */
181 static int
NgDeliverMsg(int cs,const char * path,const struct ng_mesg * hdr,const void * args,size_t arglen)182 NgDeliverMsg(int cs, const char *path,
183 const struct ng_mesg *hdr, const void *args, size_t arglen)
184 {
185 u_char sgbuf[NG_PATHSIZ + NGSA_OVERHEAD];
186 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf;
187 u_char *buf = NULL;
188 struct ng_mesg *msg;
189 int errnosv = 0;
190 int rtn = 0;
191
192 /* Sanity check */
193 if (args == NULL)
194 arglen = 0;
195
196 /* Get buffer */
197 if ((buf = malloc(sizeof(*msg) + arglen)) == NULL) {
198 errnosv = errno;
199 if (_gNgDebugLevel >= 1)
200 NGLOG("malloc");
201 rtn = -1;
202 goto done;
203 }
204 msg = (struct ng_mesg *) buf;
205
206 /* Finalize message */
207 *msg = *hdr;
208 msg->header.arglen = arglen;
209 memcpy(msg->data, args, arglen);
210
211 /* Prepare socket address */
212 sg->sg_family = AF_NETGRAPH;
213 /* XXX handle overflow */
214 strlcpy(sg->sg_data, path, NG_PATHSIZ);
215 sg->sg_len = strlen(sg->sg_data) + 1 + NGSA_OVERHEAD;
216
217 /* Debugging */
218 if (_gNgDebugLevel >= 2) {
219 NGLOGX("SENDING %s:",
220 (msg->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE");
221 _NgDebugSockaddr(sg);
222 _NgDebugMsg(msg, sg->sg_data);
223 }
224
225 /* Send it */
226 if (sendto(cs, msg, sizeof(*msg) + arglen,
227 0, (struct sockaddr *) sg, sg->sg_len) < 0) {
228 errnosv = errno;
229 if (_gNgDebugLevel >= 1)
230 NGLOG("sendto(%s)", sg->sg_data);
231 rtn = -1;
232 goto done;
233 }
234
235 /* Wait for reply if there should be one. */
236 if (msg->header.cmd & NGM_HASREPLY) {
237 struct pollfd rfds;
238 int n;
239
240 rfds.fd = cs;
241 rfds.events = POLLIN;
242 rfds.revents = 0;
243 n = poll(&rfds, 1, INFTIM);
244 if (n == -1) {
245 errnosv = errno;
246 if (_gNgDebugLevel >= 1)
247 NGLOG("poll");
248 rtn = -1;
249 }
250 }
251
252 done:
253 /* Done */
254 free(buf); /* OK if buf is NULL */
255 errno = errnosv;
256 return (rtn);
257 }
258
259 /*
260 * Receive a control message.
261 *
262 * On error, this returns -1 and sets errno.
263 * Otherwise, it returns the length of the received reply.
264 */
265 int
NgRecvMsg(int cs,struct ng_mesg * rep,size_t replen,char * path)266 NgRecvMsg(int cs, struct ng_mesg *rep, size_t replen, char *path)
267 {
268 u_char sgbuf[NG_PATHSIZ + NGSA_OVERHEAD];
269 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf;
270 socklen_t sglen = sizeof(sgbuf);
271 int len, errnosv;
272
273 /* Read reply */
274 len = recvfrom(cs, rep, replen, 0, (struct sockaddr *) sg, &sglen);
275 if (len < 0) {
276 errnosv = errno;
277 if (_gNgDebugLevel >= 1)
278 NGLOG("recvfrom");
279 goto errout;
280 }
281 if (path != NULL)
282 strlcpy(path, sg->sg_data, NG_PATHSIZ);
283
284 /* Debugging */
285 if (_gNgDebugLevel >= 2) {
286 NGLOGX("RECEIVED %s:",
287 (rep->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE");
288 _NgDebugSockaddr(sg);
289 _NgDebugMsg(rep, sg->sg_data);
290 }
291
292 /* Done */
293 return (len);
294
295 errout:
296 errno = errnosv;
297 return (-1);
298 }
299
300 /*
301 * Identical to NgRecvMsg() except buffer is dynamically allocated.
302 */
303 int
NgAllocRecvMsg(int cs,struct ng_mesg ** rep,char * path)304 NgAllocRecvMsg(int cs, struct ng_mesg **rep, char *path)
305 {
306 int len;
307 socklen_t optlen;
308
309 optlen = sizeof(len);
310 if (getsockopt(cs, SOL_SOCKET, SO_RCVBUF, &len, &optlen) == -1 ||
311 (*rep = malloc(len)) == NULL)
312 return (-1);
313 if ((len = NgRecvMsg(cs, *rep, len, path)) < 0)
314 free(*rep);
315 return (len);
316 }
317
318 /*
319 * Receive a control message and convert the arguments to ASCII
320 */
321 int
NgRecvAsciiMsg(int cs,struct ng_mesg * reply,size_t replen,char * path)322 NgRecvAsciiMsg(int cs, struct ng_mesg *reply, size_t replen, char *path)
323 {
324 struct ng_mesg *msg, *ascii;
325 int bufSize, errnosv;
326 u_char *buf;
327
328 /* Allocate buffer */
329 bufSize = 2 * sizeof(*reply) + replen;
330 if ((buf = malloc(bufSize)) == NULL)
331 return (-1);
332 msg = (struct ng_mesg *)buf;
333 ascii = (struct ng_mesg *)msg->data;
334
335 /* Get binary message */
336 if (NgRecvMsg(cs, msg, bufSize, path) < 0)
337 goto fail;
338 memcpy(reply, msg, sizeof(*msg));
339
340 /* Ask originating node to convert the arguments to ASCII */
341 if (NgSendMsg(cs, path, NGM_GENERIC_COOKIE,
342 NGM_BINARY2ASCII, msg, sizeof(*msg) + msg->header.arglen) < 0)
343 goto fail;
344 if (NgRecvMsg(cs, msg, bufSize, NULL) < 0)
345 goto fail;
346
347 /* Copy result to client buffer */
348 if (sizeof(*ascii) + ascii->header.arglen > replen) {
349 errno = ERANGE;
350 fail:
351 errnosv = errno;
352 free(buf);
353 errno = errnosv;
354 return (-1);
355 }
356 strncpy(reply->data, ascii->data, ascii->header.arglen);
357
358 /* Done */
359 free(buf);
360 return (0);
361 }
362
363 /*
364 * Identical to NgRecvAsciiMsg() except buffer is dynamically allocated.
365 */
366 int
NgAllocRecvAsciiMsg(int cs,struct ng_mesg ** reply,char * path)367 NgAllocRecvAsciiMsg(int cs, struct ng_mesg **reply, char *path)
368 {
369 int len;
370 socklen_t optlen;
371
372 optlen = sizeof(len);
373 if (getsockopt(cs, SOL_SOCKET, SO_RCVBUF, &len, &optlen) == -1 ||
374 (*reply = malloc(len)) == NULL)
375 return (-1);
376 if ((len = NgRecvAsciiMsg(cs, *reply, len, path)) < 0)
377 free(*reply);
378 return (len);
379 }
380