From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- fs/nfsd/nfsfh.c | 532 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 532 insertions(+) create mode 100644 fs/nfsd/nfsfh.c (limited to 'fs/nfsd/nfsfh.c') diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c new file mode 100644 index 000000000000..7a3e397b4ed3 --- /dev/null +++ b/fs/nfsd/nfsfh.c @@ -0,0 +1,532 @@ +/* + * linux/fs/nfsd/nfsfh.c + * + * NFS server file handle treatment. + * + * Copyright (C) 1995, 1996 Olaf Kirch + * Portions Copyright (C) 1999 G. Allen Morris III + * Extensive rewrite by Neil Brown Southern-Spring 1999 + * ... and again Southern-Winter 2001 to support export_operations + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#define NFSDDBG_FACILITY NFSDDBG_FH +#define NFSD_PARANOIA 1 +/* #define NFSD_DEBUG_VERBOSE 1 */ + + +static int nfsd_nr_verified; +static int nfsd_nr_put; + +extern struct export_operations export_op_default; + +#define CALL(ops,fun) ((ops->fun)?(ops->fun):export_op_default.fun) + +/* + * 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_dentry && ! IS_ROOT(tdentry)) { + /* make sure parents give x permission to user */ + int err; + parent = dget_parent(tdentry); + err = permission(parent->d_inode, MAY_EXEC, NULL); + if (err < 0) { + dput(parent); + break; + } + dput(tdentry); + tdentry = parent; + } + if (tdentry != exp->ex_dentry) + dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name); + rv = (tdentry == exp->ex_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 int +nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type) +{ + /* Type can be negative when creating hardlinks - not to a dir */ + if (type > 0 && (mode & S_IFMT) != type) { + if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK) + return nfserr_symlink; + else if (type == S_IFDIR) + return nfserr_notdir; + else if ((mode & S_IFMT) == S_IFDIR) + return nfserr_isdir; + else + return nfserr_inval; + } + if (type < 0 && (mode & S_IFMT) == -type) { + if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK) + return nfserr_symlink; + else if (type == -S_IFDIR) + return nfserr_isdir; + else + return nfserr_notdir; + } + return 0; +} + +/* + * Perform sanity checks on the dentry in a client's file handle. + * + * Note that the file handle dentry may need to be freed even after + * an error return. + * + * This is only called at the start of an nfsproc call, so fhp points to + * a svc_fh which is all 0 except for the over-the-wire file handle. + */ +u32 +fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access) +{ + struct knfsd_fh *fh = &fhp->fh_handle; + struct svc_export *exp = NULL; + struct dentry *dentry; + u32 error = 0; + + dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp)); + + /* keep this filehandle for possible reference when encoding attributes */ + rqstp->rq_reffh = fh; + + if (!fhp->fh_dentry) { + __u32 *datap=NULL; + __u32 tfh[3]; /* filehandle fragment for oldstyle filehandles */ + int fileid_type; + int data_left = fh->fh_size/4; + + error = nfserr_stale; + if (rqstp->rq_client == NULL) + goto out; + 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; + datap = fh->fh_auth; + if (--data_left<0) goto out; + switch (fh->fh_auth_type) { + case 0: break; + default: goto out; + } + len = key_len(fh->fh_fsid_type) / 4; + if (len == 0) goto out; + if (fh->fh_fsid_type == 2) { + /* deprecated, convert to type 3 */ + len = 3; + fh->fh_fsid_type = 3; + 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]; + } + if ((data_left -= len)<0) goto out; + exp = exp_find(rqstp->rq_client, fh->fh_fsid_type, datap, &rqstp->rq_chandle); + datap += len; + } else { + dev_t xdev; + ino_t xino; + if (fh->fh_size != NFS_FHSIZE) + goto out; + /* assume old filehandle format */ + xdev = old_decode_dev(fh->ofh_xdev); + xino = u32_to_ino_t(fh->ofh_xino); + mk_fsid_v0(tfh, xdev, xino); + exp = exp_find(rqstp->rq_client, 0, tfh, &rqstp->rq_chandle); + } + + error = nfserr_dropit; + if (IS_ERR(exp) && PTR_ERR(exp) == -EAGAIN) + goto out; + + error = nfserr_stale; + if (!exp || IS_ERR(exp)) + goto out; + + /* Check if the request originated from a secure port. */ + error = nfserr_perm; + if (!rqstp->rq_secure && EX_SECURE(exp)) { + printk(KERN_WARNING + "nfsd: request from insecure port (%u.%u.%u.%u:%d)!\n", + NIPQUAD(rqstp->rq_addr.sin_addr.s_addr), + ntohs(rqstp->rq_addr.sin_port)); + goto out; + } + + /* Set user creds for this exportpoint */ + error = nfsd_setuser(rqstp, exp); + if (error) { + error = nfserrno(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) { + tfh[0] = fh->ofh_ino; + tfh[1] = fh->ofh_generation; + tfh[2] = fh->ofh_dirino; + datap = tfh; + data_left = 3; + if (fh->ofh_dirino == 0) + fileid_type = 1; + else + fileid_type = 2; + } else + fileid_type = fh->fh_fileid_type; + + if (fileid_type == 0) + dentry = dget(exp->ex_dentry); + else { + struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op; + dentry = CALL(nop,decode_fh)(exp->ex_mnt->mnt_sb, + datap, 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; + } +#ifdef NFSD_PARANOIA + 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); + } +#endif + + fhp->fh_dentry = dentry; + fhp->fh_export = exp; + nfsd_nr_verified++; + } else { + /* just rechecking permissions + * (e.g. nfsproc_create calls fh_verify, then nfsd_create does as well) + */ + dprintk("nfsd: fh_verify - just checking\n"); + dentry = fhp->fh_dentry; + exp = fhp->fh_export; + } + cache_get(&exp->h); + + error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type); + if (error) + goto out; + + /* Finally, check access permissions. */ + error = nfsd_permission(exp, dentry, access); + +#ifdef NFSD_PARANOIA_EXTREME + if (error) { + printk("fh_verify: %s/%s permission failure, acc=%x, error=%d\n", + dentry->d_parent->d_name.name, dentry->d_name.name, access, (error >> 24)); + } +#endif +out: + if (exp && !IS_ERR(exp)) + exp_put(exp); + 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 inline int _fh_update(struct dentry *dentry, struct svc_export *exp, + __u32 *datap, int *maxsize) +{ + struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op; + + if (dentry == exp->ex_dentry) { + *maxsize = 0; + return 0; + } + + return CALL(nop,encode_fh)(dentry, datap, maxsize, + !(exp->ex_flags&NFSEXP_NOSUBTREECHECK)); +} + +/* + * 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; +} + +int +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, 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 + * + */ + + u8 ref_fh_version = 0; + u8 ref_fh_fsid_type = 0; + struct inode * inode = dentry->d_inode; + struct dentry *parent = dentry->d_parent; + __u32 *datap; + dev_t ex_dev = exp->ex_dentry->d_inode->i_sb->s_dev; + + dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n", + MAJOR(ex_dev), MINOR(ex_dev), + (long) exp->ex_dentry->d_inode->i_ino, + parent->d_name.name, dentry->d_name.name, + (inode ? inode->i_ino : 0)); + + if (ref_fh) { + ref_fh_version = ref_fh->fh_handle.fh_version; + if (ref_fh_version == 0xca) + ref_fh_fsid_type = 0; + else + ref_fh_fsid_type = ref_fh->fh_handle.fh_fsid_type; + if (ref_fh_fsid_type > 3) + ref_fh_fsid_type = 0; + + /* make sure ref_fh type works for given export */ + if (ref_fh_fsid_type == 1 && + !(exp->ex_flags & NFSEXP_FSID)) { + /* if we don't have an fsid, we cannot provide one... */ + ref_fh_fsid_type = 0; + } + } else if (exp->ex_flags & NFSEXP_FSID) + ref_fh_fsid_type = 1; + + if (!old_valid_dev(ex_dev) && ref_fh_fsid_type == 0) { + /* for newer device numbers, we must use a newer fsid format */ + ref_fh_version = 1; + ref_fh_fsid_type = 3; + } + if (old_valid_dev(ex_dev) && + (ref_fh_fsid_type == 2 || ref_fh_fsid_type == 3)) + /* must use type1 for smaller device numbers */ + ref_fh_fsid_type = 0; + + 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 (ref_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_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_version = 1; + fhp->fh_handle.fh_auth_type = 0; + datap = fhp->fh_handle.fh_auth+0; + fhp->fh_handle.fh_fsid_type = ref_fh_fsid_type; + switch (ref_fh_fsid_type) { + case 0: + /* + * fsid_type 0: + * 2byte major, 2byte minor, 4byte inode + */ + mk_fsid_v0(datap, ex_dev, + exp->ex_dentry->d_inode->i_ino); + break; + case 1: + /* fsid_type 1 == 4 bytes filesystem id */ + mk_fsid_v1(datap, exp->ex_fsid); + break; + case 2: + /* + * fsid_type 2: + * 4byte major, 4byte minor, 4byte inode + */ + mk_fsid_v2(datap, ex_dev, + exp->ex_dentry->d_inode->i_ino); + break; + case 3: + /* + * fsid_type 3: + * 4byte devicenumber, 4byte inode + */ + mk_fsid_v3(datap, ex_dev, + exp->ex_dentry->d_inode->i_ino); + break; + } + len = key_len(ref_fh_fsid_type); + datap += len/4; + fhp->fh_handle.fh_size = 4 + len; + + if (inode) { + int size = (fhp->fh_maxsize-len-4)/4; + fhp->fh_handle.fh_fileid_type = + _fh_update(dentry, exp, datap, &size); + fhp->fh_handle.fh_size += size*4; + } + if (fhp->fh_handle.fh_fileid_type == 255) + return nfserr_opnotsupp; + } + + nfsd_nr_verified++; + return 0; +} + +/* + * Update file handle information after changing a dentry. + * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create + */ +int +fh_update(struct svc_fh *fhp) +{ + struct dentry *dentry; + __u32 *datap; + + 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 { + int size; + if (fhp->fh_handle.fh_fileid_type != 0) + goto out_uptodate; + datap = fhp->fh_handle.fh_auth+ + fhp->fh_handle.fh_size/4 -1; + size = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4; + fhp->fh_handle.fh_fileid_type = + _fh_update(dentry, fhp->fh_export, datap, &size); + fhp->fh_handle.fh_size += size*4; + 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; +out_uptodate: + printk(KERN_ERR "fh_update: %s/%s already up-to-date!\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 + nfsd_nr_put++; + } + if (exp) { + svc_export_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; +} -- cgit v1.2.3