1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 23 /* 24 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 25 * Use is subject to license terms. 26 */ 27 28 #pragma ident "%Z%%M% %I% %E% SMI" 29 30 /* 31 * t_rcv.c and t_rcvv.c are very similar and contain common code. 32 * Any changes to either of them should be reviewed to see whether they 33 * are applicable to the other file. 34 */ 35 #include "mt.h" 36 #include <stdlib.h> 37 #include <errno.h> 38 #include <unistd.h> 39 #include <stropts.h> 40 #include <sys/stream.h> 41 #define _SUN_TPI_VERSION 2 42 #include <sys/tihdr.h> 43 #include <sys/timod.h> 44 #include <xti.h> 45 #include <syslog.h> 46 #include <assert.h> 47 #include "tx.h" 48 49 int 50 _tx_rcvv(int fd, struct t_iovec *tiov, unsigned int tiovcount, int *flags, 51 int api_semantics) 52 { 53 struct strbuf ctlbuf, databuf; 54 int retval, flg = 0; 55 int msglen; 56 union T_primitives *pptr; 57 struct _ti_user *tiptr; 58 int sv_errno; 59 int didalloc; 60 unsigned int nbytes; 61 char *dataptr; 62 63 if ((tiptr = _t_checkfd(fd, 0, api_semantics)) == NULL) 64 return (-1); 65 sig_mutex_lock(&tiptr->ti_lock); 66 67 if (tiptr->ti_servtype == T_CLTS) { 68 t_errno = TNOTSUPPORT; 69 sig_mutex_unlock(&tiptr->ti_lock); 70 return (-1); 71 } 72 73 assert(api_semantics == TX_XTI_XNS5_API); 74 75 if (tiovcount == 0 || tiovcount > T_IOV_MAX) { 76 t_errno = TBADDATA; 77 sig_mutex_unlock(&tiptr->ti_lock); 78 return (-1); 79 } 80 81 if (!(tiptr->ti_state == T_DATAXFER || 82 tiptr->ti_state == T_OUTREL)) { 83 t_errno = TOUTSTATE; 84 sig_mutex_unlock(&tiptr->ti_lock); 85 return (-1); 86 } 87 88 /* 89 * Check in lookbuf for stuff 90 */ 91 if (tiptr->ti_lookcnt > 0) { 92 /* 93 * Implied preference rules give priority to 94 * T_DISCON_IND over T_ORDREL_IND. Also certain errors like 95 * data received after T_ORDREL_IND or a duplicate T_ORDREL_IND 96 * after a T_ORDRELING have priority over TLOOK. 97 * This manifests in following code behavior. 98 * 99 * (1) If something in lookbuf then check 100 * the stream head also. This may result 101 * in retuning a TLOOK error but only if there are 102 * - message at stream head but look buffer 103 * has a T_DISCON_IND event. 104 * - no messages are on the stream head 105 * 106 * (2) If there are messages on the stream head and 107 * all of them are T_ORDREL_IND(i.e. no message in 108 * look buffer is T_DISCON_IND), there 109 * could be data on stream head to be picked up and 110 * we work on the stream head and not return TLOOK. 111 * We remove the event on the stream head and queue it. 112 * 113 */ 114 do { 115 retval = ioctl(fd, I_NREAD, &msglen); 116 } while (retval < 0 && errno == EINTR); 117 118 if (retval < 0) { 119 sv_errno = errno; 120 t_errno = TSYSERR; 121 sig_mutex_unlock(&tiptr->ti_lock); 122 errno = sv_errno; 123 return (-1); 124 } 125 126 if (retval > 0) { 127 /* 128 * If any T_DISCON_IND event in look buffer 129 * list then return TLOOK. Else continue 130 * processing as what could be on the stream 131 * head might be a possible T_DISCON_IND (which 132 * would have priority over the T_ORDREL_INDs 133 * on the look buffer.) 134 */ 135 struct _ti_lookbufs *tlbs; 136 137 tlbs = &tiptr->ti_lookbufs; 138 do { 139 /* LINTED pointer cast */ 140 if (*((t_scalar_t *)tlbs->tl_lookcbuf) 141 == T_DISCON_IND) { 142 t_errno = TLOOK; 143 sig_mutex_unlock(&tiptr->ti_lock); 144 return (-1); 145 } 146 } while ((tlbs = tlbs->tl_next) != NULL); 147 148 } else { /* retval == 0 */ 149 /* 150 * Nothing on stream head so whatever in 151 * look buffer has nothing that might override 152 * it. 153 */ 154 t_errno = TLOOK; 155 sig_mutex_unlock(&tiptr->ti_lock); 156 return (-1); 157 } 158 } 159 160 /* 161 * Acquire ctlbuf for use in sending/receiving control part 162 * of the message. 163 */ 164 if (_t_acquire_ctlbuf(tiptr, &ctlbuf, &didalloc) < 0) { 165 sv_errno = errno; 166 sig_mutex_unlock(&tiptr->ti_lock); 167 errno = sv_errno; 168 return (-1); 169 } 170 171 nbytes = _t_bytecount_upto_intmax(tiov, tiovcount); 172 dataptr = NULL; 173 if (nbytes != 0 && ((dataptr = malloc(nbytes)) == NULL)) { 174 sv_errno = errno; 175 t_errno = TSYSERR; 176 if (didalloc) 177 free(ctlbuf.buf); 178 else 179 tiptr->ti_ctlbuf = ctlbuf.buf; 180 sig_mutex_unlock(&tiptr->ti_lock); 181 errno = sv_errno; 182 return (-1); 183 } 184 185 databuf.maxlen = (int)nbytes; 186 databuf.len = 0; 187 databuf.buf = dataptr; 188 189 *flags = 0; 190 191 /* 192 * This is a call that may block indefinitely so we drop the 193 * lock and allow signals in MT case here and reacquire it. 194 * Error case should roll back state changes done above 195 * (happens to be no state change here) 196 */ 197 sig_mutex_unlock(&tiptr->ti_lock); 198 if ((retval = getmsg(fd, &ctlbuf, &databuf, &flg)) < 0) { 199 if (errno == EAGAIN) 200 t_errno = TNODATA; 201 else 202 t_errno = TSYSERR; 203 sv_errno = errno; 204 sig_mutex_lock(&tiptr->ti_lock); 205 errno = sv_errno; 206 goto err_out; 207 } 208 sig_mutex_lock(&tiptr->ti_lock); 209 210 assert((retval & MORECTL) == 0); /* MORECTL should not be on */ 211 212 if (databuf.len == -1) databuf.len = 0; 213 214 if (ctlbuf.len > 0) { 215 if (ctlbuf.len < (int)sizeof (t_scalar_t)) { 216 t_errno = TSYSERR; 217 errno = EPROTO; 218 goto err_out; 219 } 220 221 /* LINTED pointer cast */ 222 pptr = (union T_primitives *)ctlbuf.buf; 223 224 switch (pptr->type) { 225 226 case T_EXDATA_IND: 227 *flags |= T_EXPEDITED; 228 if (retval > 0) 229 tiptr->ti_flags |= EXPEDITED; 230 /* FALLTHROUGH */ 231 case T_DATA_IND: 232 /* 233 * Uses the fact T_DATA_IND and T_EXDATA_IND 234 * are same in size 235 */ 236 if ((ctlbuf.len < (int)sizeof (struct T_data_ind)) || 237 (tiptr->ti_lookcnt > 0)) { 238 /* 239 * ti_lookcnt > 0 implies data 240 * received after T_DISCON_IND or 241 * T_ORDREL_IND hence error 242 */ 243 t_errno = TSYSERR; 244 errno = EPROTO; 245 goto err_out; 246 } 247 248 if ((pptr->data_ind.MORE_flag) || retval) 249 *flags |= T_MORE; 250 if ((pptr->data_ind.MORE_flag) && retval) 251 tiptr->ti_flags |= MORE; 252 /* 253 * No real state change on T_RCV event (noop) 254 * 255 * We invoke the macro only for error logging 256 * part of its capabilities when in a bad state. 257 */ 258 _T_TX_NEXTSTATE(T_RCV, tiptr, 259 "t_rcvv: invalid state event T_RCV"); 260 if (didalloc) 261 free(ctlbuf.buf); 262 else 263 tiptr->ti_ctlbuf = ctlbuf.buf; 264 _t_scatter(&databuf, tiov, tiovcount); 265 if (dataptr != NULL) 266 free(dataptr); 267 sig_mutex_unlock(&tiptr->ti_lock); 268 return (databuf.len); 269 270 case T_ORDREL_IND: 271 if (tiptr->ti_lookcnt > 0) { 272 /* 273 * ti_lookcnt > 0 implies T_ORDREL_IND 274 * received after T_DISCON_IND or 275 * another T_ORDREL_IND hence error. 276 */ 277 t_errno = TSYSERR; 278 errno = EPROTO; 279 goto err_out; 280 } 281 /* FALLTHROUGH */ 282 case T_DISCON_IND: 283 /* 284 * Post event (T_ORDREL_IND/T_DISCON_IND) to 285 * the lookbuffer list. 286 */ 287 288 if (_t_register_lookevent(tiptr, databuf.buf, 289 databuf.len, 290 ctlbuf.buf, ctlbuf.len) < 0) { 291 t_errno = TSYSERR; 292 errno = ENOMEM; 293 goto err_out; 294 } 295 /* 296 * We know that T_DISCON_IND is stored in 297 * last look buffer. If there is more data 298 * that follows, we try to append it to 299 * the same look buffer 300 */ 301 if (retval & MOREDATA) { 302 ctlbuf.maxlen = 0; /* XXX why ? */ 303 ctlbuf.len = 0; 304 305 /* 306 * XXX Will break (-ve maxlen) for 307 * transport provider with unbounded 308 * T_DISCON_IND data part (-1). 309 */ 310 databuf.maxlen = 311 tiptr->ti_rcvsize - databuf.len; 312 313 databuf.len = 0; 314 databuf.buf = 315 tiptr->ti_lookbufs.tl_lookdbuf + 316 tiptr->ti_lookbufs.tl_lookdlen; 317 *flags = 0; 318 319 /* 320 * Since MOREDATA was set, we assume 321 * that this getmsg will not block 322 * indefinitely 323 */ 324 do { 325 retval = getmsg(fd, &ctlbuf, 326 &databuf, &flg); 327 } while (retval < 0 && errno == EINTR); 328 329 if (retval < 0) { 330 t_errno = TSYSERR; 331 goto err_out; 332 } 333 if (databuf.len == -1) databuf.len = 0; 334 if (retval > 0) { 335 /* MORECTL should not be on */ 336 assert((retval & MORECTL) == 0); 337 /* 338 * XXX - Why ? 339 * No support for unbounded data 340 * on T_DISCON_IND ? 341 */ 342 t_errno = TSYSERR; 343 errno = EPROTO; 344 goto err_out; 345 } 346 tiptr->ti_lookbufs.tl_lookdlen += 347 databuf.len; 348 } 349 350 t_errno = TLOOK; 351 goto err_out; 352 353 default: 354 break; 355 } 356 357 t_errno = TSYSERR; 358 errno = EPROTO; 359 goto err_out; 360 361 } else { /* else for "if (ctlbuf.len > 0)" */ 362 if (!retval && (tiptr->ti_flags & MORE)) { 363 *flags |= T_MORE; 364 tiptr->ti_flags &= ~MORE; 365 } 366 if (retval & MOREDATA) 367 *flags |= T_MORE; 368 369 /* 370 * If inside an ETSDU, set expedited flag and turn 371 * of internal version when reach end of "ETIDU". 372 */ 373 if (tiptr->ti_flags & EXPEDITED) { 374 *flags |= T_EXPEDITED; 375 if (!retval) 376 tiptr->ti_flags &= ~EXPEDITED; 377 } 378 379 /* 380 * No real state change on T_RCV events (It is a NOOP) 381 * 382 * We invoke the macro only for error logging 383 * part of its capabilities when in a bad state. 384 */ 385 _T_TX_NEXTSTATE(T_RCV, tiptr, 386 "t_rcvv: state invalid T_RCV event"); 387 if (didalloc) 388 free(ctlbuf.buf); 389 else 390 tiptr->ti_ctlbuf = ctlbuf.buf; 391 _t_scatter(&databuf, tiov, tiovcount); 392 if (dataptr != NULL) 393 free(dataptr); 394 sig_mutex_unlock(&tiptr->ti_lock); 395 return (databuf.len); 396 } 397 /* NOTREACHED */ 398 399 err_out: 400 sv_errno = errno; 401 if (didalloc) 402 free(ctlbuf.buf); 403 else 404 tiptr->ti_ctlbuf = ctlbuf.buf; 405 if (dataptr != NULL) 406 free(dataptr); 407 sig_mutex_unlock(&tiptr->ti_lock); 408 409 errno = sv_errno; 410 return (-1); 411 } 412