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
 130 /*
 131  * What is the longest we will wait before re-sending a request?
 132  * Note this is also the frequency of "RPC timeout" messages.
 133  * The re-send loop count sup linearly to this maximum, so the
 134  * first complaint will happen after (1+2+3+4+5)=15 seconds.
 135  */
 136 #define MAX_RESEND_DELAY 5      /* seconds */
 137
 138 /* copied over from nfs_boot.c for printf format. could put in .h file... */
 139 #define IP_FORMAT       "%d.%d.%d.%d"
 140 #define IP_CH(ip)       ((u_char *)ip)
 141 #define IP_LIST(ip)     IP_CH(ip)[0],IP_CH(ip)[1],IP_CH(ip)[2],IP_CH(ip)[3]
 142
 143
 144 /*
 145  * Call portmap to lookup a port number for a particular rpc program
 146  * Returns non-zero error on failure.
 147  */
 148 int
 149 krpc_portmap(
 150         struct sockaddr_in *sin,        /* server address */
 151         u_int prog, u_int vers, u_int proto,    /* host order */
 152         u_int16_t *portp)               /* network order */
 153 {
 154         struct sdata {
 155                 u_int32_t prog;         /* call program */
 156                 u_int32_t vers;         /* call version */
 157                 u_int32_t proto;        /* call protocol */
 158                 u_int32_t port;         /* call port (unused) */
 159         } *sdata;
 160         struct rdata {
 161                 u_int16_t pad;
 162                 u_int16_t port;
 163         } *rdata;
 164         mbuf_t m;
 165         int error;
 166
 167         /* The portmapper port is fixed. */
 168         if (prog == PMAPPROG) {
 169                 *portp = htons(PMAPPORT);
 170                 return 0;
 171         }
 172
 173         error = mbuf_gethdr(MBUF_WAITOK, MBUF_TYPE_DATA, &m);
 174         if (error)
 175                 return error;
 176         mbuf_setlen(m, sizeof(*sdata));
 177         mbuf_pkthdr_setlen(m, sizeof(*sdata));
 178         sdata = mbuf_data(m);
 179
 180         /* Do the RPC to get it. */
 181         sdata->prog = htonl(prog);
 182         sdata->vers = htonl(vers);
 183         sdata->proto = htonl(proto);
 184         sdata->port = 0;
 185
 186         sin->sin_port = htons(PMAPPORT);
 187         error = krpc_call(sin, SOCK_DGRAM, PMAPPROG, PMAPVERS, PMAPPROC_GETPORT, &m, NULL);
 188         if (error)
 189                 return error;
 190
 191         rdata = mbuf_data(m);
 192
 193         if (mbuf_len(m) >= sizeof(*rdata)) {
 194                 *portp = rdata->port;
 195         }
 196
 197         if (mbuf_len(m) < sizeof(*rdata) || !rdata->port)
 198                 error = EPROGUNAVAIL;
 199
 200         mbuf_freem(m);
 201         return (error);
 202 }
 203
 204 /*
 205  * Do a remote procedure call (RPC) and wait for its reply.
 206  * If from_p is non-null, then we are doing broadcast, and
 207  * the address from whence the response came is saved there.
 208  */
 209 int
 210 krpc_call(
 211         struct sockaddr_in *sa,
 212         u_int sotype, u_int prog, u_int vers, u_int func,
 213         mbuf_t *data,                   /* input/output */
 214         struct sockaddr_in *from_p)     /* output */
 215 {
 216         socket_t so;
 217         struct sockaddr_in *sin;
 218         mbuf_t m, nam, mhead;
 219         struct rpc_call *call;
 220         struct rpc_reply *reply;
 221         int error, timo, secs;
 222         size_t len;
 223         static u_int32_t xid = ~0xFF;
 224         u_int16_t tport;
 225         size_t maxpacket = 1<<16;
 226
 227         /*
 228          * Validate address family.
 229          * Sorry, this is INET specific...
 230          */
 231         if (sa->sin_family != AF_INET)
 232                 return (EAFNOSUPPORT);
 233
 234         /* Free at end if not null. */
 235         nam = mhead = NULL;
 236
 237         /*
 238          * Create socket and set its recieve timeout.
 239          */
 240         if ((error = sock_socket(AF_INET, sotype, 0, 0, 0, &so)))
 241                 goto out1;
 242
 243         {
 244                 struct timeval tv;
 245
 246                 tv.tv_sec = 1;
 247                 tv.tv_usec = 0;
 248
 249                 if ((error = sock_setsockopt(so, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv))))
 250                     goto out;
 251
 252         }
 253
 254         /*
 255          * Enable broadcast if necessary.
 256          */
 257
 258         if (from_p && (sotype == SOCK_DGRAM)) {
 259                 int on = 1;
 260                 if ((error = sock_setsockopt(so, SOL_SOCKET, SO_BROADCAST, &on, sizeof(on))))
 261                         goto out;
 262         }
 263
 264         /*
 265          * Bind the local endpoint to a reserved port,
 266          * because some NFS servers refuse requests from
 267          * non-reserved (non-privileged) ports.
 268          */
 269         if ((error = mbuf_get(MBUF_WAITOK, MBUF_TYPE_SONAME, &m)))
 270                 goto out;
 271         sin = mbuf_data(m);
 272         bzero(sin, sizeof(*sin));
 273         mbuf_setlen(m, sizeof(*sin));
 274         sin->sin_len = sizeof(*sin);
 275         sin->sin_family = AF_INET;
 276         sin->sin_addr.s_addr = INADDR_ANY;
 277         tport = IPPORT_RESERVED;
 278         do {
 279                 tport--;
 280                 sin->sin_port = htons(tport);
 281                 error = sock_bind(so, (struct sockaddr*)sin);
 282         } while (error == EADDRINUSE &&
 283                          tport > IPPORT_RESERVED / 2);
 284         mbuf_freem(m);
 285         m = NULL;
 286         if (error) {
 287                 printf("bind failed\n");
 288                 goto out;
 289         }
 290
 291         /*
 292          * Setup socket address for the server.
 293          */
 294         if ((error = mbuf_get(MBUF_WAITOK, MBUF_TYPE_SONAME, &nam)))
 295                 goto out;
 296         sin = mbuf_data(nam);
 297         mbuf_setlen(nam, sa->sin_len);
 298         bcopy((caddr_t)sa, (caddr_t)sin, sa->sin_len);
 299
 300         if (sotype == SOCK_STREAM) {
 301                 struct timeval tv;
 302                 tv.tv_sec = 60;
 303                 tv.tv_usec = 0;
 304                 error = sock_connect(so, mbuf_data(nam), MSG_DONTWAIT);
 305                 if (error && (error != EINPROGRESS))
 306                         goto out;
 307                 error = sock_connectwait(so, &tv);
 308                 if (error) {
 309                         if (error == EINPROGRESS)
 310                                 error = ETIMEDOUT;
 311                         printf("krpc_call: error waiting for TCP socket connect: %d\n", error);
 312                         goto out;
 313                 }
 314         }
 315
 316         /*
 317          * Prepend RPC message header.
 318          */
 319         m = *data;
 320         *data = NULL;
 321 #if     DIAGNOSTIC
 322         if ((mbuf_flags(m) & MBUF_PKTHDR) == 0)
 323                 panic("krpc_call: send data w/o pkthdr");
 324         if (mbuf_pkthdr_len(m) < mbuf_len(m))
 325                 panic("krpc_call: pkthdr.len not set");
 326 #endif
 327         len = sizeof(*call);
 328         if (sotype == SOCK_STREAM)
 329                 len += 4;  /* account for RPC record marker */
 330         mhead = m;
 331         if ((error = mbuf_prepend(&mhead, len, MBUF_WAITOK)))
 332                 goto out;
 333         if ((error = mbuf_pkthdr_setrcvif(mhead, NULL)))
 334                 goto out;
 335
 336         /*
 337          * Fill in the RPC header
 338          */
 339         if (sotype == SOCK_STREAM) {
 340                 /* first, fill in RPC record marker */
 341                 u_int32_t *recmark = mbuf_data(mhead);
 342                 *recmark = htonl(0x80000000 | (mbuf_pkthdr_len(mhead) - 4));
 343                 call = (struct rpc_call *)(recmark + 1);
 344         } else {
 345                 call = mbuf_data(mhead);
 346         }
 347         bzero((caddr_t)call, sizeof(*call));
 348         xid++;
 349         call->rp_xid = htonl(xid);
 350         /* call->rp_direction = 0; */
 351         call->rp_rpcvers = htonl(2);
 352         call->rp_prog = htonl(prog);
 353         call->rp_vers = htonl(vers);
 354         call->rp_proc = htonl(func);
 355         /* call->rp_auth = 0; */
 356         /* call->rp_verf = 0; */
 357
 358         /*
 359          * Send it, repeatedly, until a reply is received,
 360          * but delay each re-send by an increasing amount.
 361          * If the delay hits the maximum, start complaining.
 362          */
 363         timo = 0;
 364         for (;;) {
 365                 struct msghdr msg;
 366
 367                 /* Send RPC request (or re-send). */
 368                 if ((error = mbuf_copym(mhead, 0, MBUF_COPYALL, MBUF_WAITOK, &m)))
 369                         goto out;
 370                 bzero(&msg, sizeof(msg));
 371                 if (sotype == SOCK_STREAM) {
 372                         msg.msg_name = NULL;
 373                         msg.msg_namelen = 0;
 374                 } else {
 375                         msg.msg_name = mbuf_data(nam);
 376                         msg.msg_namelen = mbuf_len(nam);
 377                 }
 378                 error = sock_sendmbuf(so, &msg, m, 0, 0);
 379                 if (error) {
 380                         printf("krpc_call: sosend: %d\n", error);
 381                         goto out;
 382                 }
 383                 m = NULL;
 384
 385                 /* Determine new timeout. */
 386                 if (timo < MAX_RESEND_DELAY)
 387                         timo++;
 388                 else
 389                         printf("RPC timeout for server " IP_FORMAT "\n",
 390                                 IP_LIST(&(sin->sin_addr.s_addr)));
 391
 392                 /*
 393                  * Wait for up to timo seconds for a reply.
 394                  * The socket receive timeout was set to 1 second.
 395                  */
 396                 secs = timo;
 397                 while (secs > 0) {
 398                         size_t readlen;
 399
 400                         if (m) {
 401                                 mbuf_freem(m);
 402                                 m = NULL;
 403                         }
 404                         if (sotype == SOCK_STREAM) {
 405                                 int maxretries = 60;
 406                                 struct iovec aio;
 407                                 aio.iov_base = &len;
 408                                 aio.iov_len = sizeof(u_int32_t);
 409                                 bzero(&msg, sizeof(msg));
 410                                 msg.msg_iov = &aio;
 411                                 msg.msg_iovlen = 1;
 412                                 do {
 413                                    error = sock_receive(so, &msg, MSG_WAITALL, &readlen);
 414                                    if ((error == EWOULDBLOCK) && (--maxretries <= 0))
 415                                         error = ETIMEDOUT;
 416                                 } while (error == EWOULDBLOCK);
 417                                 if (!error && readlen < aio.iov_len) {
 418                                     /* only log a message if we got a partial word */
 419                                     if (readlen != 0)
 420                                             printf("short receive (%ld/%ld) from server " IP_FORMAT "\n",
 421                                                  readlen, sizeof(u_int32_t), IP_LIST(&(sin->sin_addr.s_addr)));
 422                                     error = EPIPE;
 423                                 }
 424                                 if (error)
 425                                         goto out;
 426                                 len = ntohl(len) & ~0x80000000;
 427                                 /*
 428                                  * This is SERIOUS! We are out of sync with the sender
 429                                  * and forcing a disconnect/reconnect is all I can do.
 430                                  */
 431                                 if (len > maxpacket) {
 432                                     printf("impossible packet length (%ld) from server " IP_FORMAT "\n",
 433                                         len, IP_LIST(&(sin->sin_addr.s_addr)));
 434                                     error = EFBIG;
 435                                     goto out;
 436                                 }
 437
 438                                 do {
 439                                     readlen = len;
 440                                     error = sock_receivembuf(so, NULL, &m, MSG_WAITALL, &readlen);
 441                                 } while (error == EWOULDBLOCK);
 442
 443                                 if (!error && (len > readlen)) {
 444                                     printf("short receive (%ld/%ld) from server " IP_FORMAT "\n",
 445                                         readlen, len, IP_LIST(&(sin->sin_addr.s_addr)));
 446                                     error = EPIPE;
 447                                 }
 448                         } else {
 449                                 len = maxpacket;
 450                                 readlen = len;
 451                                 bzero(&msg, sizeof(msg));
 452                                 msg.msg_name = from_p;
 453                                 msg.msg_namelen = (from_p == NULL) ? 0 : sizeof(*from_p);
 454                                 error = sock_receivembuf(so, &msg, &m, 0, &readlen);
 455                         }
 456
 457                         if (error == EWOULDBLOCK) {
 458                                 secs--;
 459                                 continue;
 460                         }
 461                         if (error)
 462                                 goto out;
 463                         len = readlen;
 464
 465                         /* Does the reply contain at least a header? */
 466                         if (len < MIN_REPLY_HDR)
 467                                 continue;
 468                         if (mbuf_len(m) < MIN_REPLY_HDR)
 469                                 continue;
 470                         reply = mbuf_data(m);
 471
 472                         /* Is it the right reply? */
 473                         if (reply->rp_direction != htonl(RPC_REPLY))
 474                                 continue;
 475
 476                         if (reply->rp_xid != htonl(xid))
 477                                 continue;
 478
 479                         /* Was RPC accepted? (authorization OK) */
 480                         if (reply->rp_astatus != 0) {
 481                                 error = ntohl(reply->rp_u.rpu_errno);
 482                                 printf("rpc denied, error=%d\n", error);
 483                                 /* convert rpc error to errno */
 484                                 switch (error) {
 485                                 case RPC_MISMATCH:
 486                                         error = ERPCMISMATCH;
 487                                         break;
 488                                 case RPC_AUTHERR:
 489                                         error = EAUTH;
 490                                         break;
 491                                 }
 492                                 goto out;
 493                         }
 494
 495                         /* Did the call succeed? */
 496                         if ((error = ntohl(reply->rp_u.rpu_ok.rp_rstatus)) != 0) {
 497                                 printf("rpc status=%d\n", error);
 498                                 /* convert rpc error to errno */
 499                                 switch (error) {
 500                                 case RPC_PROGUNAVAIL:
 501                                         error = EPROGUNAVAIL;
 502                                         break;
 503                                 case RPC_PROGMISMATCH:
 504                                         error = EPROGMISMATCH;
 505                                         break;
 506                                 case RPC_PROCUNAVAIL:
 507                                         error = EPROCUNAVAIL;
 508                                         break;
 509                                 case RPC_GARBAGE:
 510                                         error = EINVAL;
 511                                         break;
 512                                 case RPC_SYSTEM_ERR:
 513                                         error = EIO;
 514                                         break;
 515                                 }
 516                                 goto out;
 517                         }
 518
 519                         goto gotreply;  /* break two levels */
 520
 521                 } /* while secs */
 522         } /* forever send/receive */
 523
 524         error = ETIMEDOUT;
 525         goto out;
 526
 527  gotreply:
 528
 529         /*
 530          * Pull as much as we can into first mbuf, to make
 531          * result buffer contiguous.  Note that if the entire
 532          * result won't fit into one mbuf, you're out of luck.
 533          * XXX - Should not rely on making the entire reply
 534          * contiguous (fix callers instead). -gwr
 535          */
 536 #if     DIAGNOSTIC
 537         if ((mbuf_flags(m) & MBUF_PKTHDR) == 0)
 538                 panic("krpc_call: received pkt w/o header?");
 539 #endif
 540         len = mbuf_pkthdr_len(m);
 541         if (sotype == SOCK_STREAM)
 542                 len -= 4;  /* the RPC record marker was read separately */
 543         if (mbuf_len(m) < len) {
 544                 if ((error = mbuf_pullup(&m, len)))
 545                         goto out;
 546                 reply = mbuf_data(m);
 547         }
 548
 549         /*
 550          * Strip RPC header
 551          */
 552         len = sizeof(*reply);
 553         if (reply->rp_u.rpu_ok.rp_auth.rp_atype != 0) {
 554                 len += ntohl(reply->rp_u.rpu_ok.rp_auth.rp_alen);
 555                 len = (len + 3) & ~3; /* XXX? */
 556         }
 557         mbuf_adj(m, len);
 558
 559         /* result */
 560         *data = m;
 561  out:
 562         sock_close(so);
 563 out1:
 564         if (nam) mbuf_freem(nam);
 565         if (mhead) mbuf_freem(mhead);
 566         return error;
 567 }