diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/nfsd/nfsfh.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/nfsd/nfsfh.c | 690 |
1 files changed, 0 insertions, 690 deletions
diff --git a/ANDROID_3.4.5/fs/nfsd/nfsfh.c b/ANDROID_3.4.5/fs/nfsd/nfsfh.c deleted file mode 100644 index 68454e75..00000000 --- a/ANDROID_3.4.5/fs/nfsd/nfsfh.c +++ /dev/null @@ -1,690 +0,0 @@ -/* - * NFS server file handle treatment. - * - * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> - * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org> - * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999 - * ... and again Southern-Winter 2001 to support export_operations - */ - -#include <linux/exportfs.h> - -#include <linux/sunrpc/svcauth_gss.h> -#include "nfsd.h" -#include "vfs.h" -#include "auth.h" - -#define NFSDDBG_FACILITY NFSDDBG_FH - - -/* - * our acceptability function. - * if NOSUBTREECHECK, accept anything - * if not, require that we can walk up to exp->ex_dentry - * doing some checks on the 'x' bits - */ -static int nfsd_acceptable(void *expv, struct dentry *dentry) -{ - struct svc_export *exp = expv; - int rv; - struct dentry *tdentry; - struct dentry *parent; - - if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) - return 1; - - tdentry = dget(dentry); - while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) { - /* make sure parents give x permission to user */ - int err; - parent = dget_parent(tdentry); - err = inode_permission(parent->d_inode, MAY_EXEC); - if (err < 0) { - dput(parent); - break; - } - dput(tdentry); - tdentry = parent; - } - if (tdentry != exp->ex_path.dentry) - dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name); - rv = (tdentry == exp->ex_path.dentry); - dput(tdentry); - return rv; -} - -/* Type check. The correct error return for type mismatches does not seem to be - * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a - * comment in the NFSv3 spec says this is incorrect (implementation notes for - * the write call). - */ -static inline __be32 -nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, umode_t requested) -{ - mode &= S_IFMT; - - if (requested == 0) /* the caller doesn't care */ - return nfs_ok; - if (mode == requested) - return nfs_ok; - /* - * v4 has an error more specific than err_notdir which we should - * return in preference to err_notdir: - */ - if (rqstp->rq_vers == 4 && mode == S_IFLNK) - return nfserr_symlink; - if (requested == S_IFDIR) - return nfserr_notdir; - if (mode == S_IFDIR) - return nfserr_isdir; - return nfserr_inval; -} - -static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp, - struct svc_export *exp) -{ - int flags = nfsexp_flags(rqstp, exp); - - /* Check if the request originated from a secure port. */ - if (!rqstp->rq_secure && !(flags & NFSEXP_INSECURE_PORT)) { - RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); - dprintk(KERN_WARNING - "nfsd: request from insecure port %s!\n", - svc_print_addr(rqstp, buf, sizeof(buf))); - return nfserr_perm; - } - - /* Set user creds for this exportpoint */ - return nfserrno(nfsd_setuser(rqstp, exp)); -} - -static inline __be32 check_pseudo_root(struct svc_rqst *rqstp, - struct dentry *dentry, struct svc_export *exp) -{ - if (!(exp->ex_flags & NFSEXP_V4ROOT)) - return nfs_ok; - /* - * v2/v3 clients have no need for the V4ROOT export--they use - * the mount protocl instead; also, further V4ROOT checks may be - * in v4-specific code, in which case v2/v3 clients could bypass - * them. - */ - if (!nfsd_v4client(rqstp)) - return nfserr_stale; - /* - * We're exposing only the directories and symlinks that have to be - * traversed on the way to real exports: - */ - if (unlikely(!S_ISDIR(dentry->d_inode->i_mode) && - !S_ISLNK(dentry->d_inode->i_mode))) - return nfserr_stale; - /* - * A pseudoroot export gives permission to access only one - * single directory; the kernel has to make another upcall - * before granting access to anything else under it: - */ - if (unlikely(dentry != exp->ex_path.dentry)) - return nfserr_stale; - return nfs_ok; -} - -/* - * Use the given filehandle to look up the corresponding export and - * dentry. On success, the results are used to set fh_export and - * fh_dentry. - */ -static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) -{ - struct knfsd_fh *fh = &fhp->fh_handle; - struct fid *fid = NULL, sfid; - struct svc_export *exp; - struct dentry *dentry; - int fileid_type; - int data_left = fh->fh_size/4; - __be32 error; - - error = nfserr_stale; - if (rqstp->rq_vers > 2) - error = nfserr_badhandle; - if (rqstp->rq_vers == 4 && fh->fh_size == 0) - return nfserr_nofilehandle; - - if (fh->fh_version == 1) { - int len; - - if (--data_left < 0) - return error; - if (fh->fh_auth_type != 0) - return error; - len = key_len(fh->fh_fsid_type) / 4; - if (len == 0) - return error; - if (fh->fh_fsid_type == FSID_MAJOR_MINOR) { - /* deprecated, convert to type 3 */ - len = key_len(FSID_ENCODE_DEV)/4; - fh->fh_fsid_type = FSID_ENCODE_DEV; - fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1]))); - fh->fh_fsid[1] = fh->fh_fsid[2]; - } - data_left -= len; - if (data_left < 0) - return error; - exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_auth); - fid = (struct fid *)(fh->fh_auth + len); - } else { - __u32 tfh[2]; - dev_t xdev; - ino_t xino; - - if (fh->fh_size != NFS_FHSIZE) - return error; - /* assume old filehandle format */ - xdev = old_decode_dev(fh->ofh_xdev); - xino = u32_to_ino_t(fh->ofh_xino); - mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL); - exp = rqst_exp_find(rqstp, FSID_DEV, tfh); - } - - error = nfserr_stale; - if (PTR_ERR(exp) == -ENOENT) - return error; - - if (IS_ERR(exp)) - return nfserrno(PTR_ERR(exp)); - - if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) { - /* Elevate privileges so that the lack of 'r' or 'x' - * permission on some parent directory will - * not stop exportfs_decode_fh from being able - * to reconnect a directory into the dentry cache. - * The same problem can affect "SUBTREECHECK" exports, - * but as nfsd_acceptable depends on correct - * access control settings being in effect, we cannot - * fix that case easily. - */ - struct cred *new = prepare_creds(); - if (!new) - return nfserrno(-ENOMEM); - new->cap_effective = - cap_raise_nfsd_set(new->cap_effective, - new->cap_permitted); - put_cred(override_creds(new)); - put_cred(new); - } else { - error = nfsd_setuser_and_check_port(rqstp, exp); - if (error) - goto out; - } - - /* - * Look up the dentry using the NFS file handle. - */ - error = nfserr_stale; - if (rqstp->rq_vers > 2) - error = nfserr_badhandle; - - if (fh->fh_version != 1) { - sfid.i32.ino = fh->ofh_ino; - sfid.i32.gen = fh->ofh_generation; - sfid.i32.parent_ino = fh->ofh_dirino; - fid = &sfid; - data_left = 3; - if (fh->ofh_dirino == 0) - fileid_type = FILEID_INO32_GEN; - else - fileid_type = FILEID_INO32_GEN_PARENT; - } else - fileid_type = fh->fh_fileid_type; - - if (fileid_type == FILEID_ROOT) - dentry = dget(exp->ex_path.dentry); - else { - dentry = exportfs_decode_fh(exp->ex_path.mnt, fid, - data_left, fileid_type, - nfsd_acceptable, exp); - } - if (dentry == NULL) - goto out; - if (IS_ERR(dentry)) { - if (PTR_ERR(dentry) != -EINVAL) - error = nfserrno(PTR_ERR(dentry)); - goto out; - } - - if (S_ISDIR(dentry->d_inode->i_mode) && - (dentry->d_flags & DCACHE_DISCONNECTED)) { - printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n", - dentry->d_parent->d_name.name, dentry->d_name.name); - } - - fhp->fh_dentry = dentry; - fhp->fh_export = exp; - return 0; -out: - exp_put(exp); - return error; -} - -/** - * fh_verify - filehandle lookup and access checking - * @rqstp: pointer to current rpc request - * @fhp: filehandle to be verified - * @type: expected type of object pointed to by filehandle - * @access: type of access needed to object - * - * Look up a dentry from the on-the-wire filehandle, check the client's - * access to the export, and set the current task's credentials. - * - * Regardless of success or failure of fh_verify(), fh_put() should be - * called on @fhp when the caller is finished with the filehandle. - * - * fh_verify() may be called multiple times on a given filehandle, for - * example, when processing an NFSv4 compound. The first call will look - * up a dentry using the on-the-wire filehandle. Subsequent calls will - * skip the lookup and just perform the other checks and possibly change - * the current task's credentials. - * - * @type specifies the type of object expected using one of the S_IF* - * constants defined in include/linux/stat.h. The caller may use zero - * to indicate that it doesn't care, or a negative integer to indicate - * that it expects something not of the given type. - * - * @access is formed from the NFSD_MAY_* constants defined in - * include/linux/nfsd/nfsd.h. - */ -__be32 -fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access) -{ - struct svc_export *exp; - struct dentry *dentry; - __be32 error; - - dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp)); - - if (!fhp->fh_dentry) { - error = nfsd_set_fh_dentry(rqstp, fhp); - if (error) - goto out; - } - dentry = fhp->fh_dentry; - exp = fhp->fh_export; - /* - * We still have to do all these permission checks, even when - * fh_dentry is already set: - * - fh_verify may be called multiple times with different - * "access" arguments (e.g. nfsd_proc_create calls - * fh_verify(...,NFSD_MAY_EXEC) first, then later (in - * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE). - * - in the NFSv4 case, the filehandle may have been filled - * in by fh_compose, and given a dentry, but further - * compound operations performed with that filehandle - * still need permissions checks. In the worst case, a - * mountpoint crossing may have changed the export - * options, and we may now need to use a different uid - * (for example, if different id-squashing options are in - * effect on the new filesystem). - */ - error = check_pseudo_root(rqstp, dentry, exp); - if (error) - goto out; - - error = nfsd_setuser_and_check_port(rqstp, exp); - if (error) - goto out; - - error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type); - if (error) - goto out; - - /* - * pseudoflavor restrictions are not enforced on NLM, - * which clients virtually always use auth_sys for, - * even while using RPCSEC_GSS for NFS. - */ - if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS) - goto skip_pseudoflavor_check; - /* - * Clients may expect to be able to use auth_sys during mount, - * even if they use gss for everything else; see section 2.3.2 - * of rfc 2623. - */ - if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT - && exp->ex_path.dentry == dentry) - goto skip_pseudoflavor_check; - - error = check_nfsd_access(exp, rqstp); - if (error) - goto out; - -skip_pseudoflavor_check: - /* Finally, check access permissions. */ - error = nfsd_permission(rqstp, exp, dentry, access); - - if (error) { - dprintk("fh_verify: %s/%s permission failure, " - "acc=%x, error=%d\n", - dentry->d_parent->d_name.name, - dentry->d_name.name, - access, ntohl(error)); - } -out: - if (error == nfserr_stale) - nfsdstats.fh_stale++; - return error; -} - - -/* - * Compose a file handle for an NFS reply. - * - * Note that when first composed, the dentry may not yet have - * an inode. In this case a call to fh_update should be made - * before the fh goes out on the wire ... - */ -static void _fh_update(struct svc_fh *fhp, struct svc_export *exp, - struct dentry *dentry) -{ - if (dentry != exp->ex_path.dentry) { - struct fid *fid = (struct fid *) - (fhp->fh_handle.fh_auth + fhp->fh_handle.fh_size/4 - 1); - int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4; - int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK); - - fhp->fh_handle.fh_fileid_type = - exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck); - fhp->fh_handle.fh_size += maxsize * 4; - } else { - fhp->fh_handle.fh_fileid_type = FILEID_ROOT; - } -} - -/* - * for composing old style file handles - */ -static inline void _fh_update_old(struct dentry *dentry, - struct svc_export *exp, - struct knfsd_fh *fh) -{ - fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino); - fh->ofh_generation = dentry->d_inode->i_generation; - if (S_ISDIR(dentry->d_inode->i_mode) || - (exp->ex_flags & NFSEXP_NOSUBTREECHECK)) - fh->ofh_dirino = 0; -} - -static bool is_root_export(struct svc_export *exp) -{ - return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root; -} - -static struct super_block *exp_sb(struct svc_export *exp) -{ - return exp->ex_path.dentry->d_inode->i_sb; -} - -static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp) -{ - switch (fsid_type) { - case FSID_DEV: - if (!old_valid_dev(exp_sb(exp)->s_dev)) - return 0; - /* FALL THROUGH */ - case FSID_MAJOR_MINOR: - case FSID_ENCODE_DEV: - return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV; - case FSID_NUM: - return exp->ex_flags & NFSEXP_FSID; - case FSID_UUID8: - case FSID_UUID16: - if (!is_root_export(exp)) - return 0; - /* fall through */ - case FSID_UUID4_INUM: - case FSID_UUID16_INUM: - return exp->ex_uuid != NULL; - } - return 1; -} - - -static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh) -{ - u8 version; - u8 fsid_type; -retry: - version = 1; - if (ref_fh && ref_fh->fh_export == exp) { - version = ref_fh->fh_handle.fh_version; - fsid_type = ref_fh->fh_handle.fh_fsid_type; - - ref_fh = NULL; - - switch (version) { - case 0xca: - fsid_type = FSID_DEV; - break; - case 1: - break; - default: - goto retry; - } - - /* - * As the fsid -> filesystem mapping was guided by - * user-space, there is no guarantee that the filesystem - * actually supports that fsid type. If it doesn't we - * loop around again without ref_fh set. - */ - if (!fsid_type_ok_for_exp(fsid_type, exp)) - goto retry; - } else if (exp->ex_flags & NFSEXP_FSID) { - fsid_type = FSID_NUM; - } else if (exp->ex_uuid) { - if (fhp->fh_maxsize >= 64) { - if (is_root_export(exp)) - fsid_type = FSID_UUID16; - else - fsid_type = FSID_UUID16_INUM; - } else { - if (is_root_export(exp)) - fsid_type = FSID_UUID8; - else - fsid_type = FSID_UUID4_INUM; - } - } else if (!old_valid_dev(exp_sb(exp)->s_dev)) - /* for newer device numbers, we must use a newer fsid format */ - fsid_type = FSID_ENCODE_DEV; - else - fsid_type = FSID_DEV; - fhp->fh_handle.fh_version = version; - if (version) - fhp->fh_handle.fh_fsid_type = fsid_type; -} - -__be32 -fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, - struct svc_fh *ref_fh) -{ - /* ref_fh is a reference file handle. - * if it is non-null and for the same filesystem, then we should compose - * a filehandle which is of the same version, where possible. - * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca - * Then create a 32byte filehandle using nfs_fhbase_old - * - */ - - struct inode * inode = dentry->d_inode; - struct dentry *parent = dentry->d_parent; - __u32 *datap; - dev_t ex_dev = exp_sb(exp)->s_dev; - - dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n", - MAJOR(ex_dev), MINOR(ex_dev), - (long) exp->ex_path.dentry->d_inode->i_ino, - parent->d_name.name, dentry->d_name.name, - (inode ? inode->i_ino : 0)); - - /* Choose filehandle version and fsid type based on - * the reference filehandle (if it is in the same export) - * or the export options. - */ - set_version_and_fsid_type(fhp, exp, ref_fh); - - if (ref_fh == fhp) - fh_put(ref_fh); - - if (fhp->fh_locked || fhp->fh_dentry) { - printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n", - parent->d_name.name, dentry->d_name.name); - } - if (fhp->fh_maxsize < NFS_FHSIZE) - printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n", - fhp->fh_maxsize, - parent->d_name.name, dentry->d_name.name); - - fhp->fh_dentry = dget(dentry); /* our internal copy */ - fhp->fh_export = exp; - cache_get(&exp->h); - - if (fhp->fh_handle.fh_version == 0xca) { - /* old style filehandle please */ - memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE); - fhp->fh_handle.fh_size = NFS_FHSIZE; - fhp->fh_handle.ofh_dcookie = 0xfeebbaca; - fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev); - fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev; - fhp->fh_handle.ofh_xino = - ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino); - fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry)); - if (inode) - _fh_update_old(dentry, exp, &fhp->fh_handle); - } else { - int len; - fhp->fh_handle.fh_auth_type = 0; - datap = fhp->fh_handle.fh_auth+0; - mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev, - exp->ex_path.dentry->d_inode->i_ino, - exp->ex_fsid, exp->ex_uuid); - - len = key_len(fhp->fh_handle.fh_fsid_type); - datap += len/4; - fhp->fh_handle.fh_size = 4 + len; - - if (inode) - _fh_update(fhp, exp, dentry); - if (fhp->fh_handle.fh_fileid_type == 255) { - fh_put(fhp); - return nfserr_opnotsupp; - } - } - - return 0; -} - -/* - * Update file handle information after changing a dentry. - * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create - */ -__be32 -fh_update(struct svc_fh *fhp) -{ - struct dentry *dentry; - - if (!fhp->fh_dentry) - goto out_bad; - - dentry = fhp->fh_dentry; - if (!dentry->d_inode) - goto out_negative; - if (fhp->fh_handle.fh_version != 1) { - _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle); - } else { - if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT) - goto out; - - _fh_update(fhp, fhp->fh_export, dentry); - if (fhp->fh_handle.fh_fileid_type == 255) - return nfserr_opnotsupp; - } -out: - return 0; - -out_bad: - printk(KERN_ERR "fh_update: fh not verified!\n"); - goto out; -out_negative: - printk(KERN_ERR "fh_update: %s/%s still negative!\n", - dentry->d_parent->d_name.name, dentry->d_name.name); - goto out; -} - -/* - * Release a file handle. - */ -void -fh_put(struct svc_fh *fhp) -{ - struct dentry * dentry = fhp->fh_dentry; - struct svc_export * exp = fhp->fh_export; - if (dentry) { - fh_unlock(fhp); - fhp->fh_dentry = NULL; - dput(dentry); -#ifdef CONFIG_NFSD_V3 - fhp->fh_pre_saved = 0; - fhp->fh_post_saved = 0; -#endif - } - if (exp) { - cache_put(&exp->h, &svc_export_cache); - fhp->fh_export = NULL; - } - return; -} - -/* - * Shorthand for dprintk()'s - */ -char * SVCFH_fmt(struct svc_fh *fhp) -{ - struct knfsd_fh *fh = &fhp->fh_handle; - - static char buf[80]; - sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x", - fh->fh_size, - fh->fh_base.fh_pad[0], - fh->fh_base.fh_pad[1], - fh->fh_base.fh_pad[2], - fh->fh_base.fh_pad[3], - fh->fh_base.fh_pad[4], - fh->fh_base.fh_pad[5]); - return buf; -} - -enum fsid_source fsid_source(struct svc_fh *fhp) -{ - if (fhp->fh_handle.fh_version != 1) - return FSIDSOURCE_DEV; - switch(fhp->fh_handle.fh_fsid_type) { - case FSID_DEV: - case FSID_ENCODE_DEV: - case FSID_MAJOR_MINOR: - if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV) - return FSIDSOURCE_DEV; - break; - case FSID_NUM: - if (fhp->fh_export->ex_flags & NFSEXP_FSID) - return FSIDSOURCE_FSID; - break; - default: - break; - } - /* either a UUID type filehandle, or the filehandle doesn't - * match the export. - */ - if (fhp->fh_export->ex_flags & NFSEXP_FSID) - return FSIDSOURCE_FSID; - if (fhp->fh_export->ex_uuid) - return FSIDSOURCE_UUID; - return FSIDSOURCE_DEV; -} |