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 <[email protected]>
37 *
38 * $Whistle: msg.c,v 1.9 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 <stdatomic.h>
48 #include <netgraph/ng_message.h>
49 #include <netgraph/ng_socket.h>
50
51 #include "netgraph.h"
52 #include "internal.h"
53
54 /* Next message token value */
55 static _Atomic(unsigned int) gMsgId;
56
57 /* For delivering both messages and replies */
58 static int NgDeliverMsg(int cs, const char *path,
59 const struct ng_mesg *hdr, const void *args, size_t arglen);
60
61 /*
62 * Send a message to a node using control socket node "cs".
63 * Returns -1 if error and sets errno appropriately.
64 * If successful, returns the message ID (token) used.
65 */
66 int
NgSendMsg(int cs,const char * path,int cookie,int cmd,const void * args,size_t arglen)67 NgSendMsg(int cs, const char *path,
68 int cookie, int cmd, const void *args, size_t arglen)
69 {
70 struct ng_mesg msg;
71
72 /* Prepare message header */
73 memset(&msg, 0, sizeof(msg));
74 msg.header.version = NG_VERSION;
75 msg.header.typecookie = cookie;
76 msg.header.token = atomic_fetch_add(&gMsgId, 1) & INT_MAX;
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 binary->header.token = atomic_fetch_add(&gMsgId, 1) & INT_MAX;
146 binary->header.version = NG_VERSION;
147 if (NgDeliverMsg(cs,
148 path, binary, binary->data, binary->header.arglen) < 0) {
149 free(reply);
150 return (-1);
151 }
152 token = binary->header.token;
153 free(reply);
154 return (token);
155 }
156
157 /*
158 * Send a message that is a reply to a previously received message.
159 * Returns -1 and sets errno on error, otherwise returns zero.
160 */
161 int
NgSendReplyMsg(int cs,const char * path,const struct ng_mesg * msg,const void * args,size_t arglen)162 NgSendReplyMsg(int cs, const char *path,
163 const struct ng_mesg *msg, const void *args, size_t arglen)
164 {
165 struct ng_mesg rep;
166
167 /* Prepare message header */
168 rep = *msg;
169 rep.header.flags = NGF_RESP;
170
171 /* Deliver message */
172 return (NgDeliverMsg(cs, path, &rep, args, arglen));
173 }
174
175 /*
176 * Send a message to a node using control socket node "cs".
177 * Returns -1 if error and sets errno appropriately, otherwise zero.
178 */
179 static int
NgDeliverMsg(int cs,const char * path,const struct ng_mesg * hdr,const void * args,size_t arglen)180 NgDeliverMsg(int cs, const char *path,
181 const struct ng_mesg *hdr, const void *args, size_t arglen)
182 {
183 u_char sgbuf[NG_PATHSIZ + NGSA_OVERHEAD];
184 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf;
185 u_char *buf = NULL;
186 struct ng_mesg *msg;
187 int errnosv = 0;
188 int rtn = 0;
189
190 /* Sanity check */
191 if (args == NULL)
192 arglen = 0;
193
194 /* Get buffer */
195 if ((buf = malloc(sizeof(*msg) + arglen)) == NULL) {
196 errnosv = errno;
197 if (_gNgDebugLevel >= 1)
198 NGLOG("malloc");
199 rtn = -1;
200 goto done;
201 }
202 msg = (struct ng_mesg *) buf;
203
204 /* Finalize message */
205 *msg = *hdr;
206 msg->header.arglen = arglen;
207 memcpy(msg->data, args, arglen);
208
209 /* Prepare socket address */
210 sg->sg_family = AF_NETGRAPH;
211 /* XXX handle overflow */
212 strlcpy(sg->sg_data, path, NG_PATHSIZ);
213 sg->sg_len = strlen(sg->sg_data) + 1 + NGSA_OVERHEAD;
214
215 /* Debugging */
216 if (_gNgDebugLevel >= 2) {
217 NGLOGX("SENDING %s:",
218 (msg->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE");
219 _NgDebugSockaddr(sg);
220 _NgDebugMsg(msg, sg->sg_data);
221 }
222
223 /* Send it */
224 if (sendto(cs, msg, sizeof(*msg) + arglen,
225 0, (struct sockaddr *) sg, sg->sg_len) < 0) {
226 errnosv = errno;
227 if (_gNgDebugLevel >= 1)
228 NGLOG("sendto(%s)", sg->sg_data);
229 rtn = -1;
230 goto done;
231 }
232
233 /* Wait for reply if there should be one. */
234 if (msg->header.cmd & NGM_HASREPLY && !(msg->header.flags & NGF_RESP)) {
235 struct pollfd rfds;
236 int n;
237
238 rfds.fd = cs;
239 rfds.events = POLLIN;
240 rfds.revents = 0;
241 n = poll(&rfds, 1, INFTIM);
242 if (n == -1) {
243 errnosv = errno;
244 if (_gNgDebugLevel >= 1)
245 NGLOG("poll");
246 rtn = -1;
247 }
248 }
249
250 done:
251 /* Done */
252 free(buf); /* OK if buf is NULL */
253 errno = errnosv;
254 return (rtn);
255 }
256
257 /*
258 * Receive a control message.
259 *
260 * On error, this returns -1 and sets errno.
261 * Otherwise, it returns the length of the received reply.
262 */
263 int
NgRecvMsg(int cs,struct ng_mesg * rep,size_t replen,char * path)264 NgRecvMsg(int cs, struct ng_mesg *rep, size_t replen, char *path)
265 {
266 u_char sgbuf[NG_PATHSIZ + NGSA_OVERHEAD];
267 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf;
268 socklen_t sglen = sizeof(sgbuf);
269 int len, errnosv;
270
271 /* Read reply */
272 len = recvfrom(cs, rep, replen, 0, (struct sockaddr *) sg, &sglen);
273 if (len < 0) {
274 errnosv = errno;
275 if (_gNgDebugLevel >= 1)
276 NGLOG("recvfrom");
277 goto errout;
278 }
279 if (path != NULL)
280 strlcpy(path, sg->sg_data, NG_PATHSIZ);
281
282 /* Debugging */
283 if (_gNgDebugLevel >= 2) {
284 NGLOGX("RECEIVED %s:",
285 (rep->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE");
286 _NgDebugSockaddr(sg);
287 _NgDebugMsg(rep, sg->sg_data);
288 }
289
290 /* Done */
291 return (len);
292
293 errout:
294 errno = errnosv;
295 return (-1);
296 }
297
298 /*
299 * Identical to NgRecvMsg() except buffer is dynamically allocated.
300 */
301 int
NgAllocRecvMsg(int cs,struct ng_mesg ** rep,char * path)302 NgAllocRecvMsg(int cs, struct ng_mesg **rep, char *path)
303 {
304 int len;
305 socklen_t optlen;
306
307 optlen = sizeof(len);
308 if (getsockopt(cs, SOL_SOCKET, SO_RCVBUF, &len, &optlen) == -1 ||
309 (*rep = malloc(len)) == NULL)
310 return (-1);
311 if ((len = NgRecvMsg(cs, *rep, len, path)) < 0)
312 free(*rep);
313 return (len);
314 }
315
316 /*
317 * Receive a control message and convert the arguments to ASCII
318 */
319 int
NgRecvAsciiMsg(int cs,struct ng_mesg * reply,size_t replen,char * path)320 NgRecvAsciiMsg(int cs, struct ng_mesg *reply, size_t replen, char *path)
321 {
322 struct ng_mesg *msg, *ascii;
323 int bufSize, errnosv;
324 u_char *buf;
325
326 /* Allocate buffer */
327 bufSize = 2 * sizeof(*reply) + replen;
328 if ((buf = malloc(bufSize)) == NULL)
329 return (-1);
330 msg = (struct ng_mesg *)buf;
331 ascii = (struct ng_mesg *)msg->data;
332
333 /* Get binary message */
334 if (NgRecvMsg(cs, msg, bufSize, path) < 0)
335 goto fail;
336 memcpy(reply, msg, sizeof(*msg));
337
338 /* Ask originating node to convert the arguments to ASCII */
339 if (NgSendMsg(cs, path, NGM_GENERIC_COOKIE,
340 NGM_BINARY2ASCII, msg, sizeof(*msg) + msg->header.arglen) < 0)
341 goto fail;
342 if (NgRecvMsg(cs, msg, bufSize, NULL) < 0)
343 goto fail;
344
345 /* Copy result to client buffer */
346 if (sizeof(*ascii) + ascii->header.arglen > replen) {
347 errno = ERANGE;
348 fail:
349 errnosv = errno;
350 free(buf);
351 errno = errnosv;
352 return (-1);
353 }
354 strncpy(reply->data, ascii->data, ascii->header.arglen);
355
356 /* Done */
357 free(buf);
358 return (0);
359 }
360
361 /*
362 * Identical to NgRecvAsciiMsg() except buffer is dynamically allocated.
363 */
364 int
NgAllocRecvAsciiMsg(int cs,struct ng_mesg ** reply,char * path)365 NgAllocRecvAsciiMsg(int cs, struct ng_mesg **reply, char *path)
366 {
367 int len;
368 socklen_t optlen;
369
370 optlen = sizeof(len);
371 if (getsockopt(cs, SOL_SOCKET, SO_RCVBUF, &len, &optlen) == -1 ||
372 (*reply = malloc(len)) == NULL)
373 return (-1);
374 if ((len = NgRecvAsciiMsg(cs, *reply, len, path)) < 0)
375 free(*reply);
376 return (len);
377 }
378