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 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 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 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 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 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 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 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 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