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