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/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 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 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 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 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 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 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 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 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