/* * Copyright (c) 1997-1999 Erez Zadok * Copyright (c) 1990 Jan-Simon Pendry * Copyright (c) 1990 Imperial College of Science, Technology & Medicine * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * Jan-Simon Pendry at Imperial College, London. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgment: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * %W% (Berkeley) %G% * * $Id: ops_nfs.c,v 1.5 1999/03/13 17:03:28 ezk Exp $ * */ /* * Network file system */ #ifdef HAVE_CONFIG_H # include #endif /* HAVE_CONFIG_H */ #include #include /* * Convert from nfsstat to UN*X error code */ #define unx_error(e) ((int)(e)) /* * FH_TTL is the time a file handle will remain in the cache since * last being used. If the file handle becomes invalid, then it * will be flushed anyway. */ #define FH_TTL (5 * 60) /* five minutes */ #define FH_TTL_ERROR (30) /* 30 seconds */ #define FHID_ALLOC(struct) (++fh_id) /* * The NFS layer maintains a cache of file handles. * This is *fundamental* to the implementation and * also allows quick remounting when a filesystem * is accessed soon after timing out. * * The NFS server layer knows to flush this cache * when a server goes down so avoiding stale handles. * * Each cache entry keeps a hard reference to * the corresponding server. This ensures that * the server keepalive information is maintained. * * The copy of the sockaddr_in here is taken so * that the port can be twiddled to talk to mountd * instead of portmap or the NFS server as used * elsewhere. * The port# is flushed if a server goes down. * The IP address is never flushed - we assume * that the address of a mounted machine never * changes. If it does, then you have other * problems... */ typedef struct fh_cache fh_cache; struct fh_cache { qelem fh_q; /* List header */ voidp fh_wchan; /* Wait channel */ int fh_error; /* Valid data? */ int fh_id; /* Unique id */ int fh_cid; /* Callout id */ u_long fh_nfs_version; /* highest NFS version on host */ am_nfs_handle_t fh_nfs_handle; /* Handle on filesystem */ struct sockaddr_in fh_sin; /* Address of mountd */ fserver *fh_fs; /* Server holding filesystem */ char *fh_path; /* Filesystem on host */ }; /* forward definitions */ static int call_mountd(fh_cache *fp, u_long proc, fwd_fun f, voidp wchan); static int fh_id = 0; /* globals */ AUTH *nfs_auth; qelem fh_head = {&fh_head, &fh_head}; /* * Network file system operations */ am_ops nfs_ops = { "nfs", nfs_match, nfs_init, amfs_auto_fmount, nfs_fmount, amfs_auto_fumount, nfs_fumount, amfs_error_lookuppn, amfs_error_readdir, 0, /* nfs_readlink */ 0, /* nfs_mounted */ nfs_umounted, find_nfs_srvr, FS_MKMNT | FS_BACKGROUND | FS_AMQINFO }; static fh_cache * find_nfs_fhandle_cache(voidp idv, int done) { fh_cache *fp, *fp2 = 0; int id = (long) idv; /* for 64-bit archs */ ITER(fp, fh_cache, &fh_head) { if (fp->fh_id == id) { fp2 = fp; break; } } #ifdef DEBUG if (fp2) { dlog("fh cache gives fp %#lx, fs %s", (unsigned long) fp2, fp2->fh_path); } else { dlog("fh cache search failed"); } #endif /* DEBUG */ if (fp2 && !done) { fp2->fh_error = ETIMEDOUT; return 0; } return fp2; } /* * Called when a filehandle appears */ static void got_nfs_fh(voidp pkt, int len, struct sockaddr_in * sa, struct sockaddr_in * ia, voidp idv, int done) { fh_cache *fp; fp = find_nfs_fhandle_cache(idv, done); if (!fp) return; /* * retrieve the correct RPC reply for the file handle, based on the * NFS protocol version. */ #ifdef HAVE_FS_NFS3 if (fp->fh_nfs_version == NFS_VERSION3) fp->fh_error = pickup_rpc_reply(pkt, len, (voidp) &fp->fh_nfs_handle.v3, (XDRPROC_T_TYPE) xdr_mountres3); else #endif /* HAVE_FS_NFS3 */ fp->fh_error = pickup_rpc_reply(pkt, len, (voidp) &fp->fh_nfs_handle.v2, (XDRPROC_T_TYPE) xdr_fhstatus); if (!fp->fh_error) { #ifdef DEBUG dlog("got filehandle for %s:%s", fp->fh_fs->fs_host, fp->fh_path); #endif /* DEBUG */ /* * Wakeup anything sleeping on this filehandle */ if (fp->fh_wchan) { #ifdef DEBUG dlog("Calling wakeup on %#lx", (unsigned long) fp->fh_wchan); #endif /* DEBUG */ wakeup(fp->fh_wchan); } } } void flush_nfs_fhandle_cache(fserver *fs) { fh_cache *fp; ITER(fp, fh_cache, &fh_head) { if (fp->fh_fs == fs || fs == 0) { fp->fh_sin.sin_port = (u_short) 0; fp->fh_error = -1; } } } static void discard_fh(voidp v) { fh_cache *fp = v; rem_que(&fp->fh_q); if (fp->fh_fs) { #ifdef DEBUG dlog("Discarding filehandle for %s:%s", fp->fh_fs->fs_host, fp->fh_path); #endif /* DEBUG */ free_srvr(fp->fh_fs); } if (fp->fh_path) XFREE(fp->fh_path); XFREE(fp); } /* * Determine the file handle for a node */ static int prime_nfs_fhandle_cache(char *path, fserver *fs, am_nfs_handle_t *fhbuf, voidp wchan) { fh_cache *fp, *fp_save = 0; int error; int reuse_id = FALSE; #ifdef DEBUG dlog("Searching cache for %s:%s", fs->fs_host, path); #endif /* DEBUG */ /* * First search the cache */ ITER(fp, fh_cache, &fh_head) { if (fs == fp->fh_fs && STREQ(path, fp->fh_path)) { switch (fp->fh_error) { case 0: plog(XLOG_INFO, "prime_nfs_fhandle_cache: NFS version %d", (int) fp->fh_nfs_version); #ifdef HAVE_FS_NFS3 if (fp->fh_nfs_version == NFS_VERSION3) error = fp->fh_error = unx_error(fp->fh_nfs_handle.v3.fhs_status); else #endif /* HAVE_FS_NFS3 */ error = fp->fh_error = unx_error(fp->fh_nfs_handle.v2.fhs_status); if (error == 0) { if (fhbuf) { #ifdef HAVE_FS_NFS3 if (fp->fh_nfs_version == NFS_VERSION3) memmove((voidp) &(fhbuf->v3), (voidp) &(fp->fh_nfs_handle.v3), sizeof(fp->fh_nfs_handle.v3)); else #endif /* HAVE_FS_NFS3 */ memmove((voidp) &(fhbuf->v2), (voidp) &(fp->fh_nfs_handle.v2), sizeof(fp->fh_nfs_handle.v2)); } if (fp->fh_cid) untimeout(fp->fh_cid); fp->fh_cid = timeout(FH_TTL, discard_fh, (voidp) fp); } else if (error == EACCES) { /* * Now decode the file handle return code. */ plog(XLOG_INFO, "Filehandle denied for \"%s:%s\"", fs->fs_host, path); } else { errno = error; /* XXX */ plog(XLOG_INFO, "Filehandle error for \"%s:%s\": %m", fs->fs_host, path); } /* * The error was returned from the remote mount daemon. * Policy: this error will be cached for now... */ return error; case -1: /* * Still thinking about it, but we can re-use. */ fp_save = fp; reuse_id = TRUE; break; default: /* * Return the error. * Policy: make sure we recompute if required again * in case this was caused by a network failure. * This can thrash mountd's though... If you find * your mountd going slowly then: * 1. Add a fork() loop to main. * 2. Remove the call to innetgr() and don't use * netgroups, especially if you don't use YP. */ error = fp->fh_error; fp->fh_error = -1; return error; } break; } } /* * Not in cache */ if (fp_save) { fp = fp_save; /* * Re-use existing slot */ untimeout(fp->fh_cid); free_srvr(fp->fh_fs); XFREE(fp->fh_path); } else { fp = ALLOC(struct fh_cache); memset((voidp) fp, 0, sizeof(struct fh_cache)); ins_que(&fp->fh_q, &fh_head); } if (!reuse_id) fp->fh_id = FHID_ALLOC(struct ); fp->fh_wchan = wchan; fp->fh_error = -1; fp->fh_cid = timeout(FH_TTL, discard_fh, (voidp) fp); /* * if fs->fs_ip is null, remote server is probably down. */ if (!fs->fs_ip) { /* Mark the fileserver down and invalid again */ fs->fs_flags &= ~FSF_VALID; fs->fs_flags |= FSF_DOWN; error = AM_ERRNO_HOST_DOWN; return error; } /* * If the address has changed then don't try to re-use the * port information */ if (fp->fh_sin.sin_addr.s_addr != fs->fs_ip->sin_addr.s_addr) { fp->fh_sin = *fs->fs_ip; fp->fh_sin.sin_port = 0; fp->fh_nfs_version = fs->fs_version; } fp->fh_fs = dup_srvr(fs); fp->fh_path = strdup(path); error = call_mountd(fp, MOUNTPROC_MNT, got_nfs_fh, wchan); if (error) { /* * Local error - cache for a short period * just to prevent thrashing. */ untimeout(fp->fh_cid); fp->fh_cid = timeout(error < 0 ? 2 * ALLOWED_MOUNT_TIME : FH_TTL_ERROR, discard_fh, (voidp) fp); fp->fh_error = error; } else { error = fp->fh_error; } return error; } int make_nfs_auth(void) { AUTH_CREATE_GIDLIST_TYPE group_wheel = 0; /* Some NFS mounts (particularly cross-domain) require FQDNs to succeed */ #ifdef HAVE_TRANSPORT_TYPE_TLI if (gopt.flags & CFM_FULLY_QUALIFIED_HOSTS) { plog(XLOG_INFO, "Using NFS auth for fqhn \"%s\"", hostd); nfs_auth = authsys_create(hostd, 0, 0, 1, &group_wheel); } else { nfs_auth = authsys_create_default(); } #else /* not HAVE_TRANSPORT_TYPE_TLI */ if (gopt.flags & CFM_FULLY_QUALIFIED_HOSTS) { plog(XLOG_INFO, "Using NFS auth for fqhn \"%s\"", hostd); nfs_auth = authunix_create(hostd, 0, 0, 1, &group_wheel); } else { nfs_auth = authunix_create_default(); } #endif /* not HAVE_TRANSPORT_TYPE_TLI */ if (!nfs_auth) return ENOBUFS; return 0; } static int call_mountd(fh_cache *fp, u_long proc, fwd_fun f, voidp wchan) { struct rpc_msg mnt_msg; int len; char iobuf[8192]; int error; u_long mnt_version; if (!nfs_auth) { error = make_nfs_auth(); if (error) return error; } if (fp->fh_sin.sin_port == 0) { u_short port; error = nfs_srvr_port(fp->fh_fs, &port, wchan); if (error) return error; fp->fh_sin.sin_port = port; } /* find the right version of the mount protocol */ #ifdef HAVE_FS_NFS3 if (fp->fh_nfs_version == NFS_VERSION3) mnt_version = MOUNTVERS3; else #endif /* HAVE_FS_NFS3 */ mnt_version = MOUNTVERS; plog(XLOG_INFO, "call_mountd: NFS version %d, mount version %d", (int) fp->fh_nfs_version, (int) mnt_version); rpc_msg_init(&mnt_msg, MOUNTPROG, mnt_version, MOUNTPROC_NULL); len = make_rpc_packet(iobuf, sizeof(iobuf), proc, &mnt_msg, (voidp) &fp->fh_path, (XDRPROC_T_TYPE) xdr_nfspath, nfs_auth); if (len > 0) { error = fwd_packet(MK_RPC_XID(RPC_XID_MOUNTD, fp->fh_id), (voidp) iobuf, len, &fp->fh_sin, &fp->fh_sin, (voidp) ((long) fp->fh_id), /* for 64-bit archs */ f); } else { error = -len; } /* * It may be the case that we're sending to the wrong MOUNTD port. This * occurs if mountd is restarted on the server after the port has been * looked up and stored in the filehandle cache somewhere. The correct * solution, if we're going to cache port numbers is to catch the ICMP * port unreachable reply from the server and cause the portmap request * to be redone. The quick solution here is to invalidate the MOUNTD * port. */ fp->fh_sin.sin_port = 0; return error; } /* * NFS needs the local filesystem, remote filesystem * remote hostname. * Local filesystem defaults to remote and vice-versa. */ char * nfs_match(am_opts *fo) { char *xmtab; if (fo->opt_fs && !fo->opt_rfs) fo->opt_rfs = fo->opt_fs; if (!fo->opt_rfs) { plog(XLOG_USER, "nfs: no remote filesystem specified"); return NULL; } if (!fo->opt_rhost) { plog(XLOG_USER, "nfs: no remote host specified"); return NULL; } /* * Determine magic cookie to put in mtab */ xmtab = (char *) xmalloc(strlen(fo->opt_rhost) + strlen(fo->opt_rfs) + 2); sprintf(xmtab, "%s:%s", fo->opt_rhost, fo->opt_rfs); #ifdef DEBUG dlog("NFS: mounting remote server \"%s\", remote fs \"%s\" on \"%s\"", fo->opt_rhost, fo->opt_rfs, fo->opt_fs); #endif /* DEBUG */ return xmtab; } /* * Initialize am structure for nfs */ int nfs_init(mntfs *mf) { int error; am_nfs_handle_t fhs; char *colon; if (mf->mf_private) return 0; colon = strchr(mf->mf_info, ':'); if (colon == 0) return ENOENT; error = prime_nfs_fhandle_cache(colon + 1, mf->mf_server, &fhs, (voidp) mf); if (!error) { mf->mf_private = (voidp) ALLOC(am_nfs_handle_t); mf->mf_prfree = (void (*)(voidp)) free; memmove(mf->mf_private, (voidp) &fhs, sizeof(fhs)); } return error; } int mount_nfs_fh(am_nfs_handle_t *fhp, char *dir, char *fs_name, char *opts, mntfs *mf) { MTYPE_TYPE type; char *colon; char *xopts; char host[MAXHOSTNAMELEN + MAXPATHLEN + 2]; fserver *fs = mf->mf_server; u_long nfs_version = fs->fs_version; char *nfs_proto = fs->fs_proto; /* "tcp" or "udp" */ int error; int genflags; int retry; mntent_t mnt; nfs_args_t nfs_args; /* * Extract HOST name to give to kernel. * Some systems like osf1/aix3/bsd44 variants may need old code * for NFS_ARGS_NEEDS_PATH. */ if (!(colon = strchr(fs_name, ':'))) return ENOENT; #ifdef MOUNT_TABLE_ON_FILE *colon = '\0'; #endif /* MOUNT_TABLE_ON_FILE */ strncpy(host, fs_name, sizeof(host)); #ifdef MOUNT_TABLE_ON_FILE *colon = ':'; #endif /* MOUNT_TABLE_ON_FILE */ #ifdef MAXHOSTNAMELEN /* most kernels have a name length restriction */ if (strlen(host) >= MAXHOSTNAMELEN) strcpy(host + MAXHOSTNAMELEN - 3, ".."); #endif /* MAXHOSTNAMELEN */ if (mf->mf_remopts && *mf->mf_remopts && !islocalnet(fs->fs_ip->sin_addr.s_addr)) { plog(XLOG_INFO, "Using remopts=\"%s\"", mf->mf_remopts); xopts = strdup(mf->mf_remopts); } else { xopts = strdup(opts); } memset((voidp) &mnt, 0, sizeof(mnt)); mnt.mnt_dir = dir; mnt.mnt_fsname = fs_name; mnt.mnt_opts = xopts; /* * Set mount types accordingly */ #ifndef HAVE_FS_NFS3 type = MOUNT_TYPE_NFS; mnt.mnt_type = MNTTAB_TYPE_NFS; #else /* HAVE_FS_NFS3 */ if (nfs_version == NFS_VERSION3) { type = MOUNT_TYPE_NFS3; /* * Systems that include the mount table "vers" option generally do not * set the mnttab entry to "nfs3", but to "nfs" and then they set * "vers=3". Setting it to "nfs3" works, but it may break some things * like "df -t nfs" and the "quota" program (esp. on Solaris and Irix). * So on those systems, set it to "nfs". * Note: MNTTAB_OPT_VERS is always set for NFS3 (see am_compat.h). */ # if defined(MNTTAB_OPT_VERS) && defined(MOUNT_TABLE_ON_FILE) mnt.mnt_type = MNTTAB_TYPE_NFS; # else /* defined(MNTTAB_OPT_VERS) && defined(MOUNT_TABLE_ON_FILE) */ mnt.mnt_type = MNTTAB_TYPE_NFS3; # endif /* defined(MNTTAB_OPT_VERS) && defined(MOUNT_TABLE_ON_FILE) */ } else { type = MOUNT_TYPE_NFS; mnt.mnt_type = MNTTAB_TYPE_NFS; } #endif /* HAVE_FS_NFS3 */ plog(XLOG_INFO, "mount_nfs_fh: NFS version %d", (int) nfs_version); #if defined(HAVE_FS_NFS3) || defined(HAVE_TRANSPORT_TYPE_TLI) plog(XLOG_INFO, "mount_nfs_fh: using NFS transport %s", nfs_proto); #endif /* defined(HAVE_FS_NFS3) || defined(HAVE_TRANSPORT_TYPE_TLI) */ retry = hasmntval(&mnt, MNTTAB_OPT_RETRY); if (retry <= 0) retry = 1; /* XXX */ genflags = compute_mount_flags(&mnt); /* setup the many fields and flags within nfs_args */ #ifdef HAVE_TRANSPORT_TYPE_TLI compute_nfs_args(&nfs_args, &mnt, genflags, NULL, /* struct netconfig *nfsncp */ fs->fs_ip, nfs_version, nfs_proto, fhp, host, fs_name); #else /* not HAVE_TRANSPORT_TYPE_TLI */ compute_nfs_args(&nfs_args, &mnt, genflags, fs->fs_ip, nfs_version, nfs_proto, fhp, host, fs_name); #endif /* not HAVE_TRANSPORT_TYPE_TLI */ /* finally call the mounting function */ #ifdef DEBUG amuDebug(D_TRACE) { print_nfs_args(&nfs_args, nfs_version); plog(XLOG_DEBUG, "Generic mount flags 0x%x", genflags); } #endif /* DEBUG */ error = mount_fs(&mnt, genflags, (caddr_t) &nfs_args, retry, type, nfs_version, nfs_proto, mnttab_file_name); XFREE(xopts); #ifdef HAVE_TRANSPORT_TYPE_TLI free_knetconfig(nfs_args.knconf); if (nfs_args.addr) XFREE(nfs_args.addr); /* allocated in compute_nfs_args() */ #endif /* HAVE_TRANSPORT_TYPE_TLI */ return error; } static int mount_nfs(char *dir, char *fs_name, char *opts, mntfs *mf) { if (!mf->mf_private) { plog(XLOG_ERROR, "Missing filehandle for %s", fs_name); return EINVAL; } return mount_nfs_fh((am_nfs_handle_t *) mf->mf_private, dir, fs_name, opts, mf); } int nfs_fmount(mntfs *mf) { int error = 0; error = mount_nfs(mf->mf_mount, mf->mf_info, mf->mf_mopts, mf); #ifdef DEBUG if (error) { errno = error; dlog("mount_nfs: %m"); } #endif /* DEBUG */ return error; } int nfs_fumount(mntfs *mf) { int error = UMOUNT_FS(mf->mf_mount, mnttab_file_name); /* * Here is some code to unmount 'restarted' file systems. * The restarted file systems are marked as 'nfs', not * 'host', so we only have the map information for the * the top-level mount. The unmount will fail (EBUSY) * if there are anything else from the NFS server mounted * below the mount-point. This code checks to see if there * is anything mounted with the same prefix as the * file system to be unmounted ("/a/b/c" when unmounting "/a/b"). * If there is, and it is a 'restarted' file system, we unmount * it. * Added by Mike Mitchell, mcm@unx.sas.com, 09/08/93 */ if (error == EBUSY) { mntfs *new_mf; int len = strlen(mf->mf_mount); int didsome = 0; ITER(new_mf, mntfs, &mfhead) { if (new_mf->mf_ops != mf->mf_ops || new_mf->mf_refc > 1 || mf == new_mf || ((new_mf->mf_flags & (MFF_MOUNTED | MFF_UNMOUNTING | MFF_RESTART)) == (MFF_MOUNTED | MFF_RESTART))) continue; if (NSTREQ(mf->mf_mount, new_mf->mf_mount, len) && new_mf->mf_mount[len] == '/') { UMOUNT_FS(new_mf->mf_mount, mnttab_file_name); didsome = 1; } } if (didsome) error = UMOUNT_FS(mf->mf_mount, mnttab_file_name); } if (error) return error; return 0; } void nfs_umounted(am_node *mp) { /* * Don't bother to inform remote mountd that we are finished. Until a * full track of filehandles is maintained the mountd unmount callback * cannot be done correctly anyway... */ mntfs *mf = mp->am_mnt; fserver *fs; char *colon, *path; if (mf->mf_error || mf->mf_refc > 1) return; fs = mf->mf_server; /* * Call the mount daemon on the server to announce that we are not using * the fs any more. * * This is *wrong*. The mountd should be called when the fhandle is * flushed from the cache, and a reference held to the cached entry while * the fs is mounted... */ colon = path = strchr(mf->mf_info, ':'); if (fs && colon) { fh_cache f; #ifdef DEBUG dlog("calling mountd for %s", mf->mf_info); #endif /* DEBUG */ *path++ = '\0'; f.fh_path = path; f.fh_sin = *fs->fs_ip; f.fh_sin.sin_port = (u_short) 0; f.fh_nfs_version = fs->fs_version; f.fh_fs = fs; f.fh_id = 0; f.fh_error = 0; prime_nfs_fhandle_cache(colon + 1, mf->mf_server, (am_nfs_handle_t *) 0, (voidp) mf); call_mountd(&f, MOUNTPROC_UMNT, (fwd_fun) 0, (voidp) 0); *colon = ':'; } }