bsd/nfs/krpc_subr.c

   1 /*
   2  * Copyright (c) 2000-2016 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  29 /*
  30  * Copyright (c) 1994 Gordon Ross, Adam Glass
  31  * Copyright (c) 1992 Regents of the University of California.
  32  * All rights reserved.
  33  *
  34  * This software was developed by the Computer Systems Engineering group
  35  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
  36  * contributed to Berkeley.
  37  *
  38  * Redistribution and use in source and binary forms, with or without
  39  * modification, are permitted provided that the following conditions
  40  * are met:
  41  * 1. Redistributions of source code must retain the above copyright
  42  *    notice, this list of conditions and the following disclaimer.
  43  * 2. Redistributions in binary form must reproduce the above copyright
  44  *    notice, this list of conditions and the following disclaimer in the
  45  *    documentation and/or other materials provided with the distribution.
  46  * 3. All advertising materials mentioning features or use of this software
  47  *    must display the following acknowledgement:
  48  *      This product includes software developed by the University of
  49  *      California, Lawrence Berkeley Laboratory and its contributors.
  50  * 4. Neither the name of the University nor the names of its contributors
  51  *    may be used to endorse or promote products derived from this software
  52  *    without specific prior written permission.
  53  *
  54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  64  * SUCH DAMAGE.
  65  *
  66  */
  67
  68 #include <sys/param.h>
  69 #include <sys/conf.h>
  70 #include <sys/ioctl.h>
  71 #include <sys/proc.h>
  72 #include <sys/mount.h>
  73 #include <sys/kpi_mbuf.h>
  74 #include <sys/malloc.h>
  75 #include <sys/socket.h>
  76 #include <sys/socketvar.h>
  77 #include <sys/systm.h>
  78 #include <sys/reboot.h>
  79
  80 #include <net/if.h>
  81 #include <netinet/in.h>
  82
  83 #include <nfs/rpcv2.h>
  84 #include <nfs/krpc.h>
  85
  86 /*
  87  * Kernel support for Sun RPC
  88  *
  89  * Used currently for bootstrapping in nfs diskless configurations.
  90  *
  91  * Note: will not work on variable-sized rpc args/results.
  92  *       implicit size-limit of an mbuf.
  93  */
  94
  95 /*
  96  * Generic RPC headers
  97  */
  98
  99 struct auth_info {
 100         u_int32_t       rp_atype;       /* auth type */
 101         u_int32_t       rp_alen;        /* auth length */
 102 };
 103
 104 struct rpc_call {
 105         u_int32_t       rp_xid;         /* request transaction id */
 106         int32_t         rp_direction;   /* call direction (0) */
 107         u_int32_t       rp_rpcvers;     /* rpc version (2) */
 108         u_int32_t       rp_prog;        /* program */
 109         u_int32_t       rp_vers;        /* version */
 110         u_int32_t       rp_proc;        /* procedure */
 111         struct  auth_info rp_auth;
 112         struct  auth_info rp_verf;
 113 };
 114
 115 struct rpc_reply {
 116         u_int32_t rp_xid;               /* request transaction id */
 117         int32_t  rp_direction;          /* call direction (1) */
 118         int32_t  rp_astatus;            /* accept status (0: accepted) */
 119         union {
 120                 u_int32_t rpu_errno;
 121                 struct {
 122                         struct auth_info rp_auth;
 123                         u_int32_t       rp_rstatus;
 124                 } rpu_ok;
 125         } rp_u;
 126 };
 127
 128 #define MIN_REPLY_HDR 16        /* xid, dir, astat, errno */
 129 #define REPLY_SIZE 24           /* xid, dir, astat, rpu_ok */
 130
 131 /*
 132  * What is the longest we will wait before re-sending a request?
 133  * Note this is also the frequency of "RPC timeout" messages.
 134  * The re-send loop count sup linearly to this maximum, so the
 135  * first complaint will happen after (1+2+3+4+5)=15 seconds.
 136  */
 137 #define MAX_RESEND_DELAY 5      /* seconds */
 138
 139 /* copied over from nfs_boot.c for printf format. could put in .h file... */
 140 #define IP_FORMAT       "%d.%d.%d.%d"
 141 #define IP_CH(ip)       ((u_char *)ip)
 142 #define IP_LIST(ip)     IP_CH(ip)[0],IP_CH(ip)[1],IP_CH(ip)[2],IP_CH(ip)[3]
 143
 144
 145 /*
 146  * Call portmap to lookup a port number for a particular rpc program
 147  * Returns non-zero error on failure.
 148  */
 149 int
 150 krpc_portmap(
 151         struct sockaddr_in *sin,        /* server address */
 152         u_int prog, u_int vers, u_int proto,    /* host order */
 153         u_int16_t *portp)               /* network order */
 154 {
 155         struct sdata {
 156                 u_int32_t prog;         /* call program */
 157                 u_int32_t vers;         /* call version */
 158                 u_int32_t proto;        /* call protocol */
 159                 u_int32_t port;         /* call port (unused) */
 160         } *sdata;
 161         struct rdata {
 162                 u_int16_t pad;
 163                 u_int16_t port;
 164         } *rdata;
 165         mbuf_t m;
 166         int error;
 167
 168         /* The portmapper port is fixed. */
 169         if (prog == PMAPPROG) {
 170                 *portp = htons(PMAPPORT);
 171                 return 0;
 172         }
 173
 174         error = mbuf_gethdr(MBUF_WAITOK, MBUF_TYPE_DATA, &m);
 175         if (error) {
 176                 return error;
 177         }
 178         mbuf_setlen(m, sizeof(*sdata));
 179         mbuf_pkthdr_setlen(m, sizeof(*sdata));
 180         sdata = mbuf_data(m);
 181
 182         /* Do the RPC to get it. */
 183         sdata->prog = htonl(prog);
 184         sdata->vers = htonl(vers);
 185         sdata->proto = htonl(proto);
 186         sdata->port = 0;
 187
 188         sin->sin_port = htons(PMAPPORT);
 189         error = krpc_call(sin, SOCK_DGRAM, PMAPPROG, PMAPVERS, PMAPPROC_GETPORT, &m, NULL);
 190         if (error) {
 191                 return error;
 192         }
 193
 194         rdata = mbuf_data(m);
 195
 196         if (mbuf_len(m) >= sizeof(*rdata)) {
 197                 *portp = rdata->port;
 198         }
 199
 200         if (mbuf_len(m) < sizeof(*rdata) || !rdata->port) {
 201                 error = EPROGUNAVAIL;
 202         }
 203
 204         mbuf_freem(m);
 205         return error;
 206 }
 207
 208 /*
 209  * Do a remote procedure call (RPC) and wait for its reply.
 210  * If from_p is non-null, then we are doing broadcast, and
 211  * the address from whence the response came is saved there.
 212  */
 213 int
 214 krpc_call(
 215         struct sockaddr_in *sa,
 216         u_int sotype, u_int prog, u_int vers, u_int func,
 217         mbuf_t *data,                   /* input/output */
 218         struct sockaddr_in *from_p)     /* output */
 219 {
 220         socket_t so;
 221         struct sockaddr_in *sin;
 222         mbuf_t m, nam, mhead;
 223         struct rpc_call *call;
 224         struct rpc_reply *reply;
 225         int error, timo, secs;
 226         size_t len;
 227         static u_int32_t xid = ~0xFF;
 228         u_int16_t tport;
 229         size_t maxpacket = 1 << 16;
 230
 231         /*
 232          * Validate address family.
 233          * Sorry, this is INET specific...
 234          */
 235         if (sa->sin_family != AF_INET) {
 236                 return EAFNOSUPPORT;
 237         }
 238
 239         /* Free at end if not null. */
 240         nam = mhead = NULL;
 241
 242         /*
 243          * Create socket and set its recieve timeout.
 244          */
 245         if ((error = sock_socket(AF_INET, sotype, 0, 0, 0, &so))) {
 246                 goto out1;
 247         }
 248
 249         {
 250                 struct timeval tv;
 251
 252                 tv.tv_sec = 1;
 253                 tv.tv_usec = 0;
 254
 255                 if ((error = sock_setsockopt(so, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)))) {
 256                         goto out;
 257                 }
 258         }
 259
 260         /*
 261          * Enable broadcast if necessary.
 262          */
 263
 264         if (from_p && (sotype == SOCK_DGRAM)) {
 265                 int on = 1;
 266                 if ((error = sock_setsockopt(so, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on)))) {
 267                         goto out;
 268                 }
 269         }
 270
 271         /*
 272          * Bind the local endpoint to a reserved port,
 273          * because some NFS servers refuse requests from
 274          * non-reserved (non-privileged) ports.
 275          */
 276         if ((error = mbuf_get(MBUF_WAITOK, MBUF_TYPE_SONAME, &m))) {
 277                 goto out;
 278         }
 279         sin = mbuf_data(m);
 280         bzero(sin, sizeof(*sin));
 281         mbuf_setlen(m, sizeof(*sin));
 282         sin->sin_len = sizeof(*sin);
 283         sin->sin_family = AF_INET;
 284         sin->sin_addr.s_addr = INADDR_ANY;
 285         tport = IPPORT_RESERVED;
 286         do {
 287                 tport--;
 288                 sin->sin_port = htons(tport);
 289                 error = sock_bind(so, (struct sockaddr*)sin);
 290         } while (error == EADDRINUSE &&
 291             tport > IPPORT_RESERVED / 2);
 292         mbuf_freem(m);
 293         m = NULL;
 294         if (error) {
 295                 printf("bind failed\n");
 296                 goto out;
 297         }
 298
 299         /*
 300          * Setup socket address for the server.
 301          */
 302         if ((error = mbuf_get(MBUF_WAITOK, MBUF_TYPE_SONAME, &nam))) {
 303                 goto out;
 304         }
 305         sin = mbuf_data(nam);
 306         mbuf_setlen(nam, sa->sin_len);
 307         bcopy((caddr_t)sa, (caddr_t)sin, sa->sin_len);
 308
 309         if (sotype == SOCK_STREAM) {
 310                 struct timeval tv;
 311                 tv.tv_sec = 60;
 312                 tv.tv_usec = 0;
 313                 error = sock_connect(so, mbuf_data(nam), MSG_DONTWAIT);
 314                 if (error && (error != EINPROGRESS)) {
 315                         goto out;
 316                 }
 317                 error = sock_connectwait(so, &tv);
 318                 if (error) {
 319                         if (error == EINPROGRESS) {
 320                                 error = ETIMEDOUT;
 321                         }
 322                         printf("krpc_call: error waiting for TCP socket connect: %d\n", error);
 323                         goto out;
 324                 }
 325         }
 326
 327         /*
 328          * Prepend RPC message header.
 329          */
 330         m = *data;
 331         *data = NULL;
 332 #if     DIAGNOSTIC
 333         if ((mbuf_flags(m) & MBUF_PKTHDR) == 0) {
 334                 panic("krpc_call: send data w/o pkthdr");
 335         }
 336         if (mbuf_pkthdr_len(m) < mbuf_len(m)) {
 337                 panic("krpc_call: pkthdr.len not set");
 338         }
 339 #endif
 340         len = sizeof(*call);
 341         if (sotype == SOCK_STREAM) {
 342                 len += 4;  /* account for RPC record marker */
 343         }
 344         mhead = m;
 345         if ((error = mbuf_prepend(&mhead, len, MBUF_WAITOK))) {
 346                 goto out;
 347         }
 348         if ((error = mbuf_pkthdr_setrcvif(mhead, NULL))) {
 349                 goto out;
 350         }
 351
 352         /*
 353          * Fill in the RPC header
 354          */
 355         if (sotype == SOCK_STREAM) {
 356                 /* first, fill in RPC record marker */
 357                 u_int32_t *recmark = mbuf_data(mhead);
 358                 *recmark = htonl(0x80000000 | (mbuf_pkthdr_len(mhead) - 4));
 359                 call = (struct rpc_call *)(recmark + 1);
 360         } else {
 361                 call = mbuf_data(mhead);
 362         }
 363         bzero((caddr_t)call, sizeof(*call));
 364         xid++;
 365         call->rp_xid = htonl(xid);
 366         /* call->rp_direction = 0; */
 367         call->rp_rpcvers = htonl(2);
 368         call->rp_prog = htonl(prog);
 369         call->rp_vers = htonl(vers);
 370         call->rp_proc = htonl(func);
 371         /* call->rp_auth = 0; */
 372         /* call->rp_verf = 0; */
 373
 374         /*
 375          * Send it, repeatedly, until a reply is received,
 376          * but delay each re-send by an increasing amount.
 377          * If the delay hits the maximum, start complaining.
 378          */
 379         timo = 0;
 380         for (;;) {
 381                 struct msghdr msg;
 382
 383                 /* Send RPC request (or re-send). */
 384                 if ((error = mbuf_copym(mhead, 0, MBUF_COPYALL, MBUF_WAITOK, &m))) {
 385                         goto out;
 386                 }
 387                 bzero(&msg, sizeof(msg));
 388                 if (sotype == SOCK_STREAM) {
 389                         msg.msg_name = NULL;
 390                         msg.msg_namelen = 0;
 391                 } else {
 392                         msg.msg_name = mbuf_data(nam);
 393                         msg.msg_namelen = mbuf_len(nam);
 394                 }
 395                 error = sock_sendmbuf(so, &msg, m, 0, 0);
 396                 if (error) {
 397                         printf("krpc_call: sosend: %d\n", error);
 398                         goto out;
 399                 }
 400                 m = NULL;
 401
 402                 /* Determine new timeout. */
 403                 if (timo < MAX_RESEND_DELAY) {
 404                         timo++;
 405                 } else {
 406                         printf("RPC timeout for server " IP_FORMAT "\n",
 407                             IP_LIST(&(sin->sin_addr.s_addr)));
 408                 }
 409
 410                 /*
 411                  * Wait for up to timo seconds for a reply.
 412                  * The socket receive timeout was set to 1 second.
 413                  */
 414                 secs = timo;
 415                 while (secs > 0) {
 416                         size_t readlen;
 417
 418                         if (m) {
 419                                 mbuf_freem(m);
 420                                 m = NULL;
 421                         }
 422                         if (sotype == SOCK_STREAM) {
 423                                 int maxretries = 60;
 424                                 struct iovec aio;
 425                                 aio.iov_base = &len;
 426                                 aio.iov_len = sizeof(u_int32_t);
 427                                 bzero(&msg, sizeof(msg));
 428                                 msg.msg_iov = &aio;
 429                                 msg.msg_iovlen = 1;
 430                                 do {
 431                                         error = sock_receive(so, &msg, MSG_WAITALL, &readlen);
 432                                         if ((error == EWOULDBLOCK) && (--maxretries <= 0)) {
 433                                                 error = ETIMEDOUT;
 434                                         }
 435                                 } while (error == EWOULDBLOCK);
 436                                 if (!error && readlen < aio.iov_len) {
 437                                         /* only log a message if we got a partial word */
 438                                         if (readlen != 0) {
 439                                                 printf("short receive (%ld/%ld) from server " IP_FORMAT "\n",
 440                                                     readlen, sizeof(u_int32_t), IP_LIST(&(sin->sin_addr.s_addr)));
 441                                         }
 442                                         error = EPIPE;
 443                                 }
 444                                 if (error) {
 445                                         goto out;
 446                                 }
 447                                 len = ntohl(len) & ~0x80000000;
 448                                 /*
 449                                  * This is SERIOUS! We are out of sync with the sender
 450                                  * and forcing a disconnect/reconnect is all I can do.
 451                                  */
 452                                 if (len > maxpacket) {
 453                                         printf("impossible packet length (%ld) from server " IP_FORMAT "\n",
 454                                             len, IP_LIST(&(sin->sin_addr.s_addr)));
 455                                         error = EFBIG;
 456                                         goto out;
 457                                 }
 458
 459                                 do {
 460                                         readlen = len;
 461                                         error = sock_receivembuf(so, NULL, &m, MSG_WAITALL, &readlen);
 462                                 } while (error == EWOULDBLOCK);
 463
 464                                 if (!error && (len > readlen)) {
 465                                         printf("short receive (%ld/%ld) from server " IP_FORMAT "\n",
 466                                             readlen, len, IP_LIST(&(sin->sin_addr.s_addr)));
 467                                         error = EPIPE;
 468                                 }
 469                         } else {
 470                                 len = maxpacket;
 471                                 readlen = len;
 472                                 bzero(&msg, sizeof(msg));
 473                                 msg.msg_name = from_p;
 474                                 msg.msg_namelen = (from_p == NULL) ? 0 : sizeof(*from_p);
 475                                 error = sock_receivembuf(so, &msg, &m, 0, &readlen);
 476                         }
 477
 478                         if (error == EWOULDBLOCK) {
 479                                 secs--;
 480                                 continue;
 481                         }
 482                         if (error) {
 483                                 goto out;
 484                         }
 485                         len = readlen;
 486
 487                         /* Does the reply contain at least a header? */
 488                         if (len < MIN_REPLY_HDR) {
 489                                 continue;
 490                         }
 491                         if (mbuf_len(m) < MIN_REPLY_HDR) {
 492                                 continue;
 493                         }
 494                         reply = mbuf_data(m);
 495
 496                         /* Is it the right reply? */
 497                         if (reply->rp_direction != htonl(RPC_REPLY)) {
 498                                 continue;
 499                         }
 500
 501                         if (reply->rp_xid != htonl(xid)) {
 502                                 continue;
 503                         }
 504
 505                         /* Was RPC accepted? (authorization OK) */
 506                         if (reply->rp_astatus != 0) {
 507                                 error = ntohl(reply->rp_u.rpu_errno);
 508                                 printf("rpc denied, error=%d\n", error);
 509                                 /* convert rpc error to errno */
 510                                 switch (error) {
 511                                 case RPC_MISMATCH:
 512                                         error = ERPCMISMATCH;
 513                                         break;
 514                                 case RPC_AUTHERR:
 515                                         error = EAUTH;
 516                                         break;
 517                                 }
 518                                 goto out;
 519                         }
 520
 521
 522                         if (mbuf_len(m) < REPLY_SIZE) {
 523                                 error = RPC_SYSTEM_ERR;
 524                         } else {
 525                                 error = ntohl(reply->rp_u.rpu_ok.rp_rstatus);
 526                         }
 527
 528                         /* Did the call succeed? */
 529                         if (error != 0) {
 530                                 printf("rpc status=%d\n", error);
 531                                 /* convert rpc error to errno */
 532                                 switch (error) {
 533                                 case RPC_PROGUNAVAIL:
 534                                         error = EPROGUNAVAIL;
 535                                         break;
 536                                 case RPC_PROGMISMATCH:
 537                                         error = EPROGMISMATCH;
 538                                         break;
 539                                 case RPC_PROCUNAVAIL:
 540                                         error = EPROCUNAVAIL;
 541                                         break;
 542                                 case RPC_GARBAGE:
 543                                         error = EINVAL;
 544                                         break;
 545                                 case RPC_SYSTEM_ERR:
 546                                         error = EIO;
 547                                         break;
 548                                 }
 549                                 goto out;
 550                         }
 551
 552                         goto gotreply;  /* break two levels */
 553                 } /* while secs */
 554         } /* forever send/receive */
 555
 556         error = ETIMEDOUT;
 557         goto out;
 558
 559 gotreply:
 560
 561         /*
 562          * Pull as much as we can into first mbuf, to make
 563          * result buffer contiguous.  Note that if the entire
 564          * result won't fit into one mbuf, you're out of luck.
 565          * XXX - Should not rely on making the entire reply
 566          * contiguous (fix callers instead). -gwr
 567          */
 568 #if     DIAGNOSTIC
 569         if ((mbuf_flags(m) & MBUF_PKTHDR) == 0) {
 570                 panic("krpc_call: received pkt w/o header?");
 571         }
 572 #endif
 573         len = mbuf_pkthdr_len(m);
 574         if (sotype == SOCK_STREAM) {
 575                 len -= 4;  /* the RPC record marker was read separately */
 576         }
 577         if (mbuf_len(m) < len) {
 578                 if ((error = mbuf_pullup(&m, len))) {
 579                         goto out;
 580                 }
 581                 reply = mbuf_data(m);
 582         }
 583
 584         /*
 585          * Strip RPC header
 586          */
 587         len = sizeof(*reply);
 588         if (reply->rp_u.rpu_ok.rp_auth.rp_atype != 0) {
 589                 len += ntohl(reply->rp_u.rpu_ok.rp_auth.rp_alen);
 590                 len = (len + 3) & ~3; /* XXX? */
 591         }
 592         mbuf_adj(m, len);
 593
 594         /* result */
 595         *data = m;
 596 out:
 597         sock_close(so);
 598 out1:
 599         if (nam) {
 600                 mbuf_freem(nam);
 601         }
 602         if (mhead) {
 603                 mbuf_freem(mhead);
 604         }
 605         return error;
 606 }