1
2 /*
3 * msg.c
4 *
5 * Copyright (c) 1996-1999 Whistle Communications, Inc.
6 * All rights reserved.
7 *
8 * Subject to the following obligations and disclaimer of warranty, use and
9 * redistribution of this software, in source or object code forms, with or
10 * without modifications are expressly permitted by Whistle Communications;
11 * provided, however, that:
12 * 1. Any and all reproductions of the source or object code must include the
13 * copyright notice above and the following disclaimer of warranties; and
14 * 2. No rights are granted, in any manner or form, to use Whistle
15 * Communications, Inc. trademarks, including the mark "WHISTLE
16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17 * such appears in the above copyright notice or in the software.
18 *
19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35 * OF SUCH DAMAGE.
36 *
37 * Author: Archie Cobbs <archie@whistle.com>
38 *
39 * $FreeBSD: src/lib/libnetgraph/msg.c,v 1.2.2.3 2001/10/29 18:36:30 archie Exp $
40 * $DragonFly: src/lib/libnetgraph/msg.c,v 1.4 2007/06/03 23:41:25 swildner Exp $
41 * $Whistle: msg.c,v 1.9 1999/01/20 00:57:23 archie Exp $
42 */
43
44 #include <sys/types.h>
45 #include <stdarg.h>
46 #include <netgraph/ng_message.h>
47 #include <netgraph/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(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 const int bufSize = 1024;
95 char replybuf[2 * sizeof(struct ng_mesg) + bufSize];
96 struct ng_mesg *const reply = (struct ng_mesg *)replybuf;
97 struct ng_mesg *const binary = (struct ng_mesg *)reply->data;
98 struct ng_mesg *ascii;
99 char *buf, *cmd, *args;
100 va_list fmtargs;
101
102 /* Parse out command and arguments */
103 va_start(fmtargs, fmt);
104 vasprintf(&buf, fmt, fmtargs);
105 va_end(fmtargs);
106 if (buf == NULL)
107 return (-1);
108
109 /* Parse out command, arguments */
110 for (cmd = buf; isspace(*cmd); cmd++)
111 ;
112 for (args = cmd; *args != '\0' && !isspace(*args); args++)
113 ;
114 if (*args != '\0') {
115 while (isspace(*args))
116 *args++ = '\0';
117 }
118
119 /* Get a bigger buffer to hold inner message header plus arg string */
120 if ((ascii = malloc(sizeof(struct ng_mesg)
121 + strlen(args) + 1)) == NULL) {
122 free(buf);
123 return (-1);
124 }
125 memset(ascii, 0, sizeof(*ascii));
126
127 /* Build inner header (only need cmdstr, arglen, and data fields) */
128 strncpy(ascii->header.cmdstr, cmd, sizeof(ascii->header.cmdstr) - 1);
129 strcpy(ascii->data, args);
130 ascii->header.arglen = strlen(ascii->data) + 1;
131 free(buf);
132
133 /* Send node a request to convert ASCII to binary */
134 if (NgSendMsg(cs, path, NGM_GENERIC_COOKIE, NGM_ASCII2BINARY,
135 (u_char *)ascii, sizeof(*ascii) + ascii->header.arglen) < 0)
136 return (-1);
137
138 /* Get reply */
139 if (NgRecvMsg(cs, reply, sizeof(replybuf), NULL) < 0)
140 return (-1);
141
142 /* Now send binary version */
143 if (++gMsgId < 0)
144 gMsgId = 1;
145 binary->header.token = gMsgId;
146 if (NgDeliverMsg(cs,
147 path, binary, binary->data, binary->header.arglen) < 0)
148 return (-1);
149 return (binary->header.token);
150 }
151
152 /*
153 * Send a message that is a reply to a previously received message.
154 * Returns -1 and sets errno on error, otherwise returns zero.
155 */
156 int
NgSendReplyMsg(int cs,const char * path,const struct ng_mesg * msg,const void * args,size_t arglen)157 NgSendReplyMsg(int cs, const char *path,
158 const struct ng_mesg *msg, const void *args, size_t arglen)
159 {
160 struct ng_mesg rep;
161
162 /* Prepare message header */
163 rep = *msg;
164 rep.header.flags = NGF_RESP;
165
166 /* Deliver message */
167 return (NgDeliverMsg(cs, path, &rep, args, arglen));
168 }
169
170 /*
171 * Send a message to a node using control socket node "cs".
172 * Returns -1 if error and sets errno appropriately, otherwise zero.
173 */
174 static int
NgDeliverMsg(int cs,const char * path,const struct ng_mesg * hdr,const void * args,size_t arglen)175 NgDeliverMsg(int cs, const char *path,
176 const struct ng_mesg *hdr, const void *args, size_t arglen)
177 {
178 u_char sgbuf[NG_PATHSIZ + 2];
179 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf;
180 u_char *buf = NULL;
181 struct ng_mesg *msg;
182 int errnosv = 0;
183 int rtn = 0;
184
185 /* Sanity check */
186 if (args == NULL)
187 arglen = 0;
188
189 /* Get buffer */
190 if ((buf = malloc(sizeof(*msg) + arglen)) == NULL) {
191 errnosv = errno;
192 if (_gNgDebugLevel >= 1)
193 NGLOG("malloc");
194 rtn = -1;
195 goto done;
196 }
197 msg = (struct ng_mesg *) buf;
198
199 /* Finalize message */
200 *msg = *hdr;
201 msg->header.arglen = arglen;
202 memcpy(msg->data, args, arglen);
203
204 /* Prepare socket address */
205 sg->sg_family = AF_NETGRAPH;
206 snprintf(sg->sg_data, NG_PATHSIZ, "%s", path);
207 sg->sg_len = strlen(sg->sg_data) + 3;
208
209 /* Debugging */
210 if (_gNgDebugLevel >= 2) {
211 NGLOGX("SENDING %s:",
212 (msg->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE");
213 _NgDebugSockaddr(sg);
214 _NgDebugMsg(msg, sg->sg_data);
215 }
216
217 /* Send it */
218 if (sendto(cs, msg, sizeof(*msg) + arglen,
219 0, (struct sockaddr *) sg, sg->sg_len) < 0) {
220 errnosv = errno;
221 if (_gNgDebugLevel >= 1)
222 NGLOG("sendto(%s)", sg->sg_data);
223 rtn = -1;
224 goto done;
225 }
226
227 done:
228 /* Done */
229 free(buf); /* OK if buf is NULL */
230 errno = errnosv;
231 return (rtn);
232 }
233
234 /*
235 * Receive a control message.
236 *
237 * On error, this returns -1 and sets errno.
238 * Otherwise, it returns the length of the received reply.
239 */
240 int
NgRecvMsg(int cs,struct ng_mesg * rep,size_t replen,char * path)241 NgRecvMsg(int cs, struct ng_mesg *rep, size_t replen, char *path)
242 {
243 u_char sgbuf[NG_PATHSIZ - 1 + sizeof(struct sockaddr_ng)];
244 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf;
245 int len, sglen = sizeof(sgbuf);
246 int errnosv;
247
248 /* Read reply */
249 len = recvfrom(cs, rep, replen, 0, (struct sockaddr *) sg, &sglen);
250 if (len < 0) {
251 errnosv = errno;
252 if (_gNgDebugLevel >= 1)
253 NGLOG("recvfrom");
254 goto errout;
255 }
256 if (path != NULL)
257 snprintf(path, NG_PATHSIZ, "%s", sg->sg_data);
258
259 /* Debugging */
260 if (_gNgDebugLevel >= 2) {
261 NGLOGX("RECEIVED %s:",
262 (rep->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE");
263 _NgDebugSockaddr(sg);
264 _NgDebugMsg(rep, sg->sg_data);
265 }
266
267 /* Done */
268 return (len);
269
270 errout:
271 errno = errnosv;
272 return (-1);
273 }
274
275 /*
276 * Receive a control message and convert the arguments to ASCII
277 */
278 int
NgRecvAsciiMsg(int cs,struct ng_mesg * reply,size_t replen,char * path)279 NgRecvAsciiMsg(int cs, struct ng_mesg *reply, size_t replen, char *path)
280 {
281 struct ng_mesg *msg, *ascii;
282 int bufSize, errnosv;
283 u_char *buf;
284
285 /* Allocate buffer */
286 bufSize = 2 * sizeof(*reply) + replen;
287 if ((buf = malloc(bufSize)) == NULL)
288 return (-1);
289 msg = (struct ng_mesg *)buf;
290 ascii = (struct ng_mesg *)msg->data;
291
292 /* Get binary message */
293 if (NgRecvMsg(cs, msg, bufSize, path) < 0)
294 goto fail;
295 memcpy(reply, msg, sizeof(*msg));
296
297 /* Ask originating node to convert the arguments to ASCII */
298 if (NgSendMsg(cs, path, NGM_GENERIC_COOKIE,
299 NGM_BINARY2ASCII, msg, sizeof(*msg) + msg->header.arglen) < 0)
300 goto fail;
301 if (NgRecvMsg(cs, msg, bufSize, NULL) < 0)
302 goto fail;
303
304 /* Copy result to client buffer */
305 if (sizeof(*ascii) + ascii->header.arglen > replen) {
306 errno = ERANGE;
307 fail:
308 errnosv = errno;
309 free(buf);
310 errno = errnosv;
311 return (-1);
312 }
313 strncpy(reply->data, ascii->data, ascii->header.arglen);
314
315 /* Done */
316 free(buf);
317 return (0);
318 }
319
320