sys/nfs/krpc_subr.c

   1 /*      $NetBSD: krpc_subr.c,v 1.36 2009/03/14 21:04:25 dsl Exp $       */
   2
   3 /*
   4  * Copyright (c) 1995 Gordon Ross, Adam Glass
   5  * Copyright (c) 1992 Regents of the University of California.
   6  * All rights reserved.
   7  *
   8  * This software was developed by the Computer Systems Engineering group
   9  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
  10  * contributed to Berkeley.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. All advertising materials mentioning features or use of this software
  21  *    must display the following acknowledgement:
  22  *      This product includes software developed by the University of
  23  *      California, Lawrence Berkeley Laboratory and its contributors.
  24  * 4. Neither the name of the University nor the names of its contributors
  25  *    may be used to endorse or promote products derived from this software
  26  *    without specific prior written permission.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  38  * SUCH DAMAGE.
  39  *
  40  * partially based on:
  41  *      libnetboot/rpc.c
  42  *               @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp  (LBL)
  43  */
  44
  45 #include <sys/cdefs.h>
  46 __KERNEL_RCSID(0, "$NetBSD: krpc_subr.c,v 1.36 2009/03/14 21:04:25 dsl Exp $");
  47
  48 #include <sys/param.h>
  49 #include <sys/systm.h>
  50 #include <sys/ioctl.h>
  51 #include <sys/proc.h>
  52 #include <sys/mount.h>
  53 #include <sys/mbuf.h>
  54 #include <sys/reboot.h>
  55 #include <sys/socket.h>
  56 #include <sys/socketvar.h>
  57
  58 #include <netinet/in.h>
  59
  60 #include <nfs/rpcv2.h>
  61 #include <nfs/krpc.h>
  62 #include <nfs/xdr_subs.h>
  63 #include <nfs/nfsproto.h> /* XXX NFSX_V3FHMAX for next */
  64 #include <nfs/nfs.h>
  65 #include <nfs/nfsmount.h>
  66 #include <nfs/nfsdiskless.h> /* XXX decl nfs_boot_sendrecv */
  67
  68 /*
  69  * Kernel support for Sun RPC
  70  *
  71  * Used currently for bootstrapping in nfs diskless configurations.
  72  */
  73
  74 /*
  75  * Generic RPC headers
  76  */
  77
  78 struct auth_info {
  79         u_int32_t       authtype;       /* auth type */
  80         u_int32_t       authlen;        /* auth length */
  81 };
  82
  83 struct auth_unix {
  84         int32_t   ua_time;
  85         int32_t   ua_hostname;  /* null */
  86         int32_t   ua_uid;
  87         int32_t   ua_gid;
  88         int32_t   ua_gidlist;   /* null */
  89 };
  90
  91 struct rpc_call {
  92         u_int32_t       rp_xid;         /* request transaction id */
  93         int32_t         rp_direction;   /* call direction (0) */
  94         u_int32_t       rp_rpcvers;     /* rpc version (2) */
  95         u_int32_t       rp_prog;        /* program */
  96         u_int32_t       rp_vers;        /* version */
  97         u_int32_t       rp_proc;        /* procedure */
  98         struct  auth_info rpc_auth;
  99         struct  auth_unix rpc_unix;
 100         struct  auth_info rpc_verf;
 101 };
 102
 103 struct rpc_reply {
 104         u_int32_t rp_xid;               /* request transaction id */
 105         int32_t  rp_direction;          /* call direction (1) */
 106         int32_t  rp_astatus;            /* accept status (0: accepted) */
 107         union {
 108                 /* rejected */
 109                 struct {
 110                         u_int32_t rej_stat;
 111                         u_int32_t rej_val1;
 112                         u_int32_t rej_val2;
 113                 } rpu_rej;
 114                 /* accepted */
 115                 struct {
 116                         struct auth_info rok_auth;
 117                         u_int32_t       rok_status;
 118                 } rpu_rok;
 119         } rp_u;
 120 };
 121 #define rp_rstat  rp_u.rpu_rej.rej_stat
 122 #define rp_auth   rp_u.rpu_rok.rok_auth
 123 #define rp_status rp_u.rpu_rok.rok_status
 124
 125 #define MIN_REPLY_HDR 16        /* xid, dir, astat, errno */
 126
 127 static int krpccheck(struct mbuf*, void*);
 128
 129 /*
 130  * Call portmap to lookup a port number for a particular rpc program
 131  * Returns non-zero error on failure.
 132  */
 133 int
 134 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int proto, u_int16_t *portp, struct lwp *l)
 135         /* sin:          server address */
 136         /* prog, vers, proto:    host order */
 137         /* portp:        network order */
 138 {
 139         struct sdata {
 140                 u_int32_t prog;         /* call program */
 141                 u_int32_t vers;         /* call version */
 142                 u_int32_t proto;        /* call protocol */
 143                 u_int32_t port;         /* call port (unused) */
 144         } *sdata;
 145         struct rdata {
 146                 u_int16_t pad;
 147                 u_int16_t port;
 148         } *rdata;
 149         struct mbuf *m;
 150         int error;
 151
 152         /* The portmapper port is fixed. */
 153         if (prog == PMAPPROG) {
 154                 *portp = htons(PMAPPORT);
 155                 return 0;
 156         }
 157
 158         m = m_get(M_WAIT, MT_DATA);
 159         sdata = mtod(m, struct sdata *);
 160         m->m_len = sizeof(*sdata);
 161
 162         /* Do the RPC to get it. */
 163         sdata->prog = txdr_unsigned(prog);
 164         sdata->vers = txdr_unsigned(vers);
 165         sdata->proto = txdr_unsigned(proto);
 166         sdata->port = 0;
 167
 168         sin->sin_port = htons(PMAPPORT);
 169         error = krpc_call(sin, PMAPPROG, PMAPVERS,
 170                                           PMAPPROC_GETPORT, &m, NULL, l);
 171         if (error)
 172                 return error;
 173
 174         if (m->m_len < sizeof(*rdata)) {
 175                 m = m_pullup(m, sizeof(*rdata));
 176                 if (m == NULL)
 177                         return ENOBUFS;
 178         }
 179         rdata = mtod(m, struct rdata *);
 180         *portp = rdata->port;
 181
 182         m_freem(m);
 183         return 0;
 184 }
 185
 186 static int krpccheck(struct mbuf *m, void *context)
 187 {
 188         struct rpc_reply *reply;
 189
 190         /* Does the reply contain at least a header? */
 191         if (m->m_pkthdr.len < MIN_REPLY_HDR)
 192                 return(-1);
 193         if (m->m_len < sizeof(struct rpc_reply)) {
 194                 m = m_pullup(m, sizeof(struct rpc_reply));
 195                 if (m == NULL)
 196                         return(-1);
 197         }
 198         reply = mtod(m, struct rpc_reply *);
 199
 200         /* Is it the right reply? */
 201         if (reply->rp_direction != txdr_unsigned(RPC_REPLY))
 202                 return(-1);
 203
 204         if (reply->rp_xid != txdr_unsigned(*(u_int32_t*)context))
 205                 return(-1);
 206
 207         return(0);
 208 }
 209
 210 /*
 211  * Do a remote procedure call (RPC) and wait for its reply.
 212  * If from_p is non-null, then we are doing broadcast, and
 213  * the address from whence the response came is saved there.
 214  */
 215 int
 216 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, struct mbuf **data, struct mbuf **from_p, struct lwp *l)
 217         /* data:         input/output */
 218         /* from_p:       output */
 219 {
 220         struct socket *so;
 221         struct sockaddr_in *sin;
 222         struct mbuf *m, *nam, *mhead, *from;
 223         struct rpc_call *call;
 224         struct rpc_reply *reply;
 225         int error, len;
 226         static u_int32_t xid = ~0xFF;
 227         u_int16_t tport;
 228
 229         /*
 230          * Validate address family.
 231          * Sorry, this is INET specific...
 232          */
 233         if (sa->sin_family != AF_INET)
 234                 return (EAFNOSUPPORT);
 235
 236         /* Free at end if not null. */
 237         nam = mhead = NULL;
 238         from = NULL;
 239
 240         /*
 241          * Create socket and set its receive timeout.
 242          */
 243         if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, l, NULL)))
 244                 goto out;
 245
 246         if ((error = nfs_boot_setrecvtimo(so)))
 247                 goto out;
 248
 249         /*
 250          * Enable broadcast if necessary.
 251          */
 252         if (from_p) {
 253                 if ((error = nfs_boot_enbroadcast(so)))
 254                         goto out;
 255         }
 256
 257         /*
 258          * Bind the local endpoint to a reserved port,
 259          * because some NFS servers refuse requests from
 260          * non-reserved (non-privileged) ports.
 261          */
 262         tport = IPPORT_RESERVED;
 263         do {
 264                 tport--;
 265                 error = nfs_boot_sobind_ipport(so, tport, l);
 266         } while (error == EADDRINUSE &&
 267                          tport > IPPORT_RESERVED / 2);
 268         if (error) {
 269                 printf("bind failed\n");
 270                 goto out;
 271         }
 272
 273         /*
 274          * Setup socket address for the server.
 275          */
 276         nam = m_get(M_WAIT, MT_SONAME);
 277         sin = mtod(nam, struct sockaddr_in *);
 278         memcpy((void *)sin, (void *)sa,
 279                   (nam->m_len = sa->sin_len));
 280
 281         /*
 282          * Prepend RPC message header.
 283          */
 284         mhead = m_gethdr(M_WAIT, MT_DATA);
 285         mhead->m_next = *data;
 286         call = mtod(mhead, struct rpc_call *);
 287         mhead->m_len = sizeof(*call);
 288         memset((void *)call, 0, sizeof(*call));
 289         /* rpc_call part */
 290         xid++;
 291         call->rp_xid = txdr_unsigned(xid);
 292         /* call->rp_direction = 0; */
 293         call->rp_rpcvers = txdr_unsigned(2);
 294         call->rp_prog = txdr_unsigned(prog);
 295         call->rp_vers = txdr_unsigned(vers);
 296         call->rp_proc = txdr_unsigned(func);
 297         /* rpc_auth part (auth_unix as root) */
 298         call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX);
 299         call->rpc_auth.authlen  = txdr_unsigned(sizeof(struct auth_unix));
 300         /* rpc_verf part (auth_null) */
 301         call->rpc_verf.authtype = 0;
 302         call->rpc_verf.authlen  = 0;
 303
 304         /*
 305          * Setup packet header
 306          */
 307         len = 0;
 308         m = mhead;
 309         while (m) {
 310                 len += m->m_len;
 311                 m = m->m_next;
 312         }
 313         mhead->m_pkthdr.len = len;
 314         mhead->m_pkthdr.rcvif = NULL;
 315
 316         error = nfs_boot_sendrecv(so, nam, 0, mhead, krpccheck, &m, &from,
 317             &xid, l);
 318         if (error)
 319                 goto out;
 320
 321         /* m_pullup() was done in krpccheck() */
 322         reply = mtod(m, struct rpc_reply *);
 323
 324         /* Was RPC accepted? (authorization OK) */
 325         if (reply->rp_astatus != 0) {
 326                 /* Note: This is NOT an error code! */
 327                 error = fxdr_unsigned(u_int32_t, reply->rp_rstat);
 328                 switch (error) {
 329                     case RPC_MISMATCH:
 330                         /* .re_status = RPC_VERSMISMATCH; */
 331                         error = ERPCMISMATCH;
 332                         break;
 333                     case RPC_AUTHERR:
 334                         /* .re_status = RPC_AUTHERROR; */
 335                         error = EAUTH;
 336                         break;
 337                     default:
 338                         /* unexpected */
 339                         error = EBADRPC;
 340                         break;
 341                 }
 342                 goto out;
 343         }
 344
 345         /* Did the call succeed? */
 346         if (reply->rp_status != 0) {
 347                 /* Note: This is NOT an error code! */
 348                 error = fxdr_unsigned(u_int32_t, reply->rp_status);
 349                 switch (error) {
 350                     case RPC_PROGUNAVAIL:
 351                         error = EPROGUNAVAIL;
 352                         break;
 353                     case RPC_PROGMISMATCH:
 354                         error = EPROGMISMATCH;
 355                         break;
 356                     case RPC_PROCUNAVAIL:
 357                         error = EPROCUNAVAIL;
 358                         break;
 359                     case RPC_GARBAGE:
 360                     default:
 361                         error = EBADRPC;
 362                 }
 363                 goto out;
 364         }
 365
 366         /*
 367          * OK, we have received a good reply!
 368          * Get its length, then strip it off.
 369          */
 370         len = sizeof(*reply);
 371         if (reply->rp_auth.authtype != 0) {
 372                 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen);
 373                 len = (len + 3) & ~3; /* XXX? */
 374         }
 375         m_adj(m, len);
 376
 377         /* result */
 378         *data = m;
 379         if (from_p && error == 0) {
 380                 *from_p = from;
 381                 from = NULL;
 382         }
 383
 384  out:
 385         if (nam) m_freem(nam);
 386         if (mhead) m_freem(mhead);
 387         if (from) m_freem(from);
 388         soclose(so);
 389         return error;
 390 }
 391
 392 /*
 393  * eXternal Data Representation routines.
 394  * (but with non-standard args...)
 395  */
 396
 397 /*
 398  * String representation for RPC.
 399  */
 400 struct xdr_string {
 401         u_int32_t len;          /* length without null or padding */
 402         char data[4];   /* data (longer, of course) */
 403     /* data is padded to a long-word boundary */
 404 };
 405
 406 struct mbuf *
 407 xdr_string_encode(char *str, int len)
 408 {
 409         struct mbuf *m;
 410         struct xdr_string *xs;
 411         int dlen;       /* padded string length */
 412         int mlen;       /* message length */
 413
 414         dlen = (len + 3) & ~3;
 415         mlen = dlen + 4;
 416
 417         if (mlen > MCLBYTES)            /* If too big, we just can't do it. */
 418                 return (NULL);
 419
 420         m = m_get(M_WAIT, MT_DATA);
 421         if (mlen > MLEN) {
 422                 m_clget(m, M_WAIT);
 423                 if ((m->m_flags & M_EXT) == 0) {
 424                         (void) m_free(m);       /* There can be only one. */
 425                         return (NULL);
 426                 }
 427         }
 428         xs = mtod(m, struct xdr_string *);
 429         m->m_len = mlen;
 430         xs->len = txdr_unsigned(len);
 431         memcpy(xs->data, str, len);
 432         return (m);
 433 }
 434
 435 struct mbuf *
 436 xdr_string_decode(struct mbuf *m, char *str, int *len_p)
 437         /* len_p:                bufsize - 1 */
 438 {
 439         struct xdr_string *xs;
 440         int mlen;       /* message length */
 441         int slen;       /* string length */
 442
 443         if (m->m_len < 4) {
 444                 m = m_pullup(m, 4);
 445                 if (m == NULL)
 446                         return (NULL);
 447         }
 448         xs = mtod(m, struct xdr_string *);
 449         slen = fxdr_unsigned(u_int32_t, xs->len);
 450         mlen = 4 + ((slen + 3) & ~3);
 451
 452         if (slen > *len_p)
 453                 slen = *len_p;
 454         m_copydata(m, 4, slen, str);
 455         m_adj(m, mlen);
 456
 457         str[slen] = '\0';
 458         *len_p = slen;
 459
 460         return (m);
 461 }
 462
 463
 464 /*
 465  * Inet address in RPC messages
 466  * (Note, really four ints, NOT chars.  Blech.)
 467  */
 468 struct xdr_inaddr {
 469         u_int32_t atype;
 470         u_int32_t addr[4];
 471 };
 472
 473 struct mbuf *
 474 xdr_inaddr_encode(struct in_addr *ia)
 475         /* ia:           already in network order */
 476 {
 477         struct mbuf *m;
 478         struct xdr_inaddr *xi;
 479         u_int8_t *cp;
 480         u_int32_t *ip;
 481
 482         m = m_get(M_WAIT, MT_DATA);
 483         xi = mtod(m, struct xdr_inaddr *);
 484         m->m_len = sizeof(*xi);
 485         xi->atype = txdr_unsigned(1);
 486         ip = xi->addr;
 487         cp = (u_int8_t *)&ia->s_addr;
 488         *ip++ = txdr_unsigned(*cp++);
 489         *ip++ = txdr_unsigned(*cp++);
 490         *ip++ = txdr_unsigned(*cp++);
 491         *ip++ = txdr_unsigned(*cp++);
 492
 493         return (m);
 494 }
 495
 496 struct mbuf *
 497 xdr_inaddr_decode(struct mbuf *m, struct in_addr *ia)
 498         /* ia:           already in network order */
 499 {
 500         struct xdr_inaddr *xi;
 501         u_int8_t *cp;
 502         u_int32_t *ip;
 503
 504         if (m->m_len < sizeof(*xi)) {
 505                 m = m_pullup(m, sizeof(*xi));
 506                 if (m == NULL)
 507                         return (NULL);
 508         }
 509         xi = mtod(m, struct xdr_inaddr *);
 510         if (xi->atype != txdr_unsigned(1)) {
 511                 ia->s_addr = INADDR_ANY;
 512                 goto out;
 513         }
 514         ip = xi->addr;
 515         cp = (u_int8_t *)&ia->s_addr;
 516         *cp++ = fxdr_unsigned(u_int8_t, *ip++);
 517         *cp++ = fxdr_unsigned(u_int8_t, *ip++);
 518         *cp++ = fxdr_unsigned(u_int8_t, *ip++);
 519         *cp++ = fxdr_unsigned(u_int8_t, *ip++);
 520
 521 out:
 522         m_adj(m, sizeof(*xi));
 523         return (m);
 524 }