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