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 #ifdef FSTACK 42 #define _GNU_SOURCE 43 #include <stdio.h> 44 #endif 45 46 #include <sys/cdefs.h> 47 __FBSDID("$FreeBSD$"); 48 49 #include <sys/types.h> 50 #include <sys/socket.h> 51 #include <stdarg.h> 52 #ifndef FSTACK 53 #include <stdatomic.h> 54 #endif 55 #include <netgraph/ng_message.h> 56 #include <netgraph/ng_socket.h> 57 58 #include "netgraph.h" 59 #include "internal.h" 60 61 #ifdef FSTACK 62 #define _Atomic(T) T volatile 63 64 #ifndef __ATOMIC_SEQ_CST 65 #define __ATOMIC_SEQ_CST 5 66 #endif 67 68 typedef enum { 69 memory_order_seq_cst = __ATOMIC_SEQ_CST 70 } memory_order; 71 72 #define atomic_fetch_add(object, operand) \ 73 atomic_fetch_add_explicit(object, operand, memory_order_seq_cst) 74 #define atomic_fetch_add_explicit(object, operand, order) \ 75 __atomic_fetch_add(object, operand, order) 76 #endif 77 78 /* Next message token value */ 79 static _Atomic(unsigned int) gMsgId; 80 81 /* For delivering both messages and replies */ 82 static int NgDeliverMsg(int cs, const char *path, 83 const struct ng_mesg *hdr, const void *args, size_t arglen); 84 85 /* 86 * Send a message to a node using control socket node "cs". 87 * Returns -1 if error and sets errno appropriately. 88 * If successful, returns the message ID (token) used. 89 */ 90 int 91 NgSendMsg(int cs, const char *path, 92 int cookie, int cmd, const void *args, size_t arglen) 93 { 94 struct ng_mesg msg; 95 96 /* Prepare message header */ 97 memset(&msg, 0, sizeof(msg)); 98 msg.header.version = NG_VERSION; 99 msg.header.typecookie = cookie; 100 msg.header.token = atomic_fetch_add(&gMsgId, 1) & INT_MAX; 101 msg.header.flags = NGF_ORIG; 102 msg.header.cmd = cmd; 103 snprintf((char *)msg.header.cmdstr, NG_CMDSTRSIZ, "cmd%d", cmd); 104 105 /* Deliver message */ 106 if (NgDeliverMsg(cs, path, &msg, args, arglen) < 0) 107 return (-1); 108 return (msg.header.token); 109 } 110 111 /* 112 * Send a message given in ASCII format. We first ask the node to translate 113 * the command into binary, and then we send the binary. 114 */ 115 int 116 NgSendAsciiMsg(int cs, const char *path, const char *fmt, ...) 117 { 118 struct ng_mesg *reply, *binary, *ascii; 119 char *buf, *cmd, *args; 120 va_list fmtargs; 121 int token; 122 123 /* Parse out command and arguments */ 124 va_start(fmtargs, fmt); 125 vasprintf(&buf, fmt, fmtargs); 126 va_end(fmtargs); 127 if (buf == NULL) 128 return (-1); 129 130 /* Parse out command, arguments */ 131 for (cmd = buf; isspace(*cmd); cmd++) 132 ; 133 for (args = cmd; *args != '\0' && !isspace(*args); args++) 134 ; 135 if (*args != '\0') { 136 while (isspace(*args)) 137 *args++ = '\0'; 138 } 139 140 /* Get a bigger buffer to hold inner message header plus arg string */ 141 if ((ascii = malloc(sizeof(struct ng_mesg) 142 + strlen(args) + 1)) == NULL) { 143 free(buf); 144 return (-1); 145 } 146 memset(ascii, 0, sizeof(*ascii)); 147 148 /* Build inner header (only need cmdstr, arglen, and data fields) */ 149 strncpy((char *)ascii->header.cmdstr, cmd, 150 sizeof(ascii->header.cmdstr) - 1); 151 strcpy(ascii->data, args); 152 ascii->header.arglen = strlen(ascii->data) + 1; 153 free(buf); 154 155 /* Send node a request to convert ASCII to binary */ 156 if (NgSendMsg(cs, path, NGM_GENERIC_COOKIE, NGM_ASCII2BINARY, 157 (u_char *)ascii, sizeof(*ascii) + ascii->header.arglen) < 0) { 158 free(ascii); 159 return (-1); 160 } 161 free(ascii); 162 163 /* Get reply */ 164 if (NgAllocRecvMsg(cs, &reply, NULL) < 0) 165 return (-1); 166 167 /* Now send binary version */ 168 binary = (struct ng_mesg *)reply->data; 169 binary->header.token = atomic_fetch_add(&gMsgId, 1) & INT_MAX; 170 binary->header.version = NG_VERSION; 171 if (NgDeliverMsg(cs, 172 path, binary, binary->data, binary->header.arglen) < 0) { 173 free(reply); 174 return (-1); 175 } 176 token = binary->header.token; 177 free(reply); 178 return (token); 179 } 180 181 /* 182 * Send a message that is a reply to a previously received message. 183 * Returns -1 and sets errno on error, otherwise returns zero. 184 */ 185 int 186 NgSendReplyMsg(int cs, const char *path, 187 const struct ng_mesg *msg, const void *args, size_t arglen) 188 { 189 struct ng_mesg rep; 190 191 /* Prepare message header */ 192 rep = *msg; 193 rep.header.flags = NGF_RESP; 194 195 /* Deliver message */ 196 return (NgDeliverMsg(cs, path, &rep, args, arglen)); 197 } 198 199 /* 200 * Send a message to a node using control socket node "cs". 201 * Returns -1 if error and sets errno appropriately, otherwise zero. 202 */ 203 static int 204 NgDeliverMsg(int cs, const char *path, 205 const struct ng_mesg *hdr, const void *args, size_t arglen) 206 { 207 u_char sgbuf[NG_PATHSIZ + NGSA_OVERHEAD]; 208 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf; 209 u_char *buf = NULL; 210 struct ng_mesg *msg; 211 int errnosv = 0; 212 int rtn = 0; 213 214 /* Sanity check */ 215 if (args == NULL) 216 arglen = 0; 217 218 /* Get buffer */ 219 if ((buf = malloc(sizeof(*msg) + arglen)) == NULL) { 220 errnosv = errno; 221 if (_gNgDebugLevel >= 1) 222 NGLOG("malloc"); 223 rtn = -1; 224 goto done; 225 } 226 msg = (struct ng_mesg *) buf; 227 228 /* Finalize message */ 229 *msg = *hdr; 230 msg->header.arglen = arglen; 231 memcpy(msg->data, args, arglen); 232 233 /* Prepare socket address */ 234 sg->sg_family = AF_NETGRAPH; 235 /* XXX handle overflow */ 236 strlcpy(sg->sg_data, path, NG_PATHSIZ); 237 sg->sg_len = strlen(sg->sg_data) + 1 + NGSA_OVERHEAD; 238 239 /* Debugging */ 240 if (_gNgDebugLevel >= 2) { 241 NGLOGX("SENDING %s:", 242 (msg->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE"); 243 _NgDebugSockaddr(sg); 244 _NgDebugMsg(msg, sg->sg_data); 245 } 246 247 /* Send it */ 248 if (sendto(cs, msg, sizeof(*msg) + arglen, 249 0, (struct sockaddr *) sg, sg->sg_len) < 0) { 250 errnosv = errno; 251 if (_gNgDebugLevel >= 1) 252 NGLOG("sendto(%s)", sg->sg_data); 253 rtn = -1; 254 goto done; 255 } 256 257 #ifndef FSTACK 258 /* Wait for reply if there should be one. */ 259 if (msg->header.cmd & NGM_HASREPLY && !(msg->header.flags & NGF_RESP)) { 260 struct pollfd rfds; 261 int n; 262 263 rfds.fd = cs; 264 rfds.events = POLLIN; 265 rfds.revents = 0; 266 n = poll(&rfds, 1, INFTIM); 267 if (n == -1) { 268 errnosv = errno; 269 if (_gNgDebugLevel >= 1) 270 NGLOG("poll"); 271 rtn = -1; 272 } 273 } 274 #endif 275 276 done: 277 /* Done */ 278 free(buf); /* OK if buf is NULL */ 279 errno = errnosv; 280 return (rtn); 281 } 282 283 /* 284 * Receive a control message. 285 * 286 * On error, this returns -1 and sets errno. 287 * Otherwise, it returns the length of the received reply. 288 */ 289 int 290 NgRecvMsg(int cs, struct ng_mesg *rep, size_t replen, char *path) 291 { 292 u_char sgbuf[NG_PATHSIZ + NGSA_OVERHEAD]; 293 struct sockaddr_ng *const sg = (struct sockaddr_ng *) sgbuf; 294 socklen_t sglen = sizeof(sgbuf); 295 int len, errnosv; 296 297 /* Read reply */ 298 len = recvfrom(cs, rep, replen, 0, (struct sockaddr *) sg, &sglen); 299 if (len < 0) { 300 errnosv = errno; 301 if (_gNgDebugLevel >= 1) 302 NGLOG("recvfrom"); 303 goto errout; 304 } 305 if (path != NULL) 306 strlcpy(path, sg->sg_data, NG_PATHSIZ); 307 308 /* Debugging */ 309 if (_gNgDebugLevel >= 2) { 310 NGLOGX("RECEIVED %s:", 311 (rep->header.flags & NGF_RESP) ? "RESPONSE" : "MESSAGE"); 312 _NgDebugSockaddr(sg); 313 _NgDebugMsg(rep, sg->sg_data); 314 } 315 316 /* Done */ 317 return (len); 318 319 errout: 320 errno = errnosv; 321 return (-1); 322 } 323 324 /* 325 * Identical to NgRecvMsg() except buffer is dynamically allocated. 326 */ 327 int 328 NgAllocRecvMsg(int cs, struct ng_mesg **rep, char *path) 329 { 330 int len; 331 #ifndef FSTACK 332 socklen_t optlen; 333 334 optlen = sizeof(len); 335 if (getsockopt(cs, SOL_SOCKET, SO_RCVBUF, &len, &optlen) == -1 || 336 #else 337 len = NGCTL_DEFAULT_RCVBUF; 338 if ( 339 #endif 340 (*rep = malloc(len)) == NULL) 341 return (-1); 342 if ((len = NgRecvMsg(cs, *rep, len, path)) < 0) 343 free(*rep); 344 return (len); 345 } 346 347 /* 348 * Receive a control message and convert the arguments to ASCII 349 */ 350 int 351 NgRecvAsciiMsg(int cs, struct ng_mesg *reply, size_t replen, char *path) 352 { 353 struct ng_mesg *msg, *ascii; 354 int bufSize, errnosv; 355 u_char *buf; 356 357 /* Allocate buffer */ 358 bufSize = 2 * sizeof(*reply) + replen; 359 if ((buf = malloc(bufSize)) == NULL) 360 return (-1); 361 msg = (struct ng_mesg *)buf; 362 ascii = (struct ng_mesg *)msg->data; 363 364 /* Get binary message */ 365 if (NgRecvMsg(cs, msg, bufSize, path) < 0) 366 goto fail; 367 memcpy(reply, msg, sizeof(*msg)); 368 369 /* Ask originating node to convert the arguments to ASCII */ 370 if (NgSendMsg(cs, path, NGM_GENERIC_COOKIE, 371 NGM_BINARY2ASCII, msg, sizeof(*msg) + msg->header.arglen) < 0) 372 goto fail; 373 if (NgRecvMsg(cs, msg, bufSize, NULL) < 0) 374 goto fail; 375 376 /* Copy result to client buffer */ 377 if (sizeof(*ascii) + ascii->header.arglen > replen) { 378 errno = ERANGE; 379 fail: 380 errnosv = errno; 381 free(buf); 382 errno = errnosv; 383 return (-1); 384 } 385 strncpy(reply->data, ascii->data, ascii->header.arglen); 386 387 /* Done */ 388 free(buf); 389 return (0); 390 } 391 392 /* 393 * Identical to NgRecvAsciiMsg() except buffer is dynamically allocated. 394 */ 395 int 396 NgAllocRecvAsciiMsg(int cs, struct ng_mesg **reply, char *path) 397 { 398 int len; 399 #ifndef FSTACK 400 socklen_t optlen; 401 402 optlen = sizeof(len); 403 if (getsockopt(cs, SOL_SOCKET, SO_RCVBUF, &len, &optlen) == -1 || 404 #else 405 len = NGCTL_DEFAULT_RCVBUF; 406 if ( 407 #endif 408 (*reply = malloc(len)) == NULL) 409 return (-1); 410 if ((len = NgRecvAsciiMsg(cs, *reply, len, path)) < 0) 411 free(*reply); 412 return (len); 413 } 414