diff options
Diffstat (limited to 'fs/nfsd/nfsxdr.c')
-rw-r--r-- | fs/nfsd/nfsxdr.c | 616 |
1 files changed, 616 insertions, 0 deletions
diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c new file mode 100644 index 000000000..8a288c8fc --- /dev/null +++ b/fs/nfsd/nfsxdr.c @@ -0,0 +1,616 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * XDR support for nfsd + * + * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> + */ + +#include "vfs.h" +#include "xdr.h" +#include "auth.h" + +#define NFSDDBG_FACILITY NFSDDBG_XDR + +/* + * Mapping of S_IF* types to NFS file types + */ +static u32 nfs_ftypes[] = { + NFNON, NFCHR, NFCHR, NFBAD, + NFDIR, NFBAD, NFBLK, NFBAD, + NFREG, NFBAD, NFLNK, NFBAD, + NFSOCK, NFBAD, NFLNK, NFBAD, +}; + + +/* + * XDR functions for basic NFS types + */ +static __be32 * +decode_fh(__be32 *p, struct svc_fh *fhp) +{ + fh_init(fhp, NFS_FHSIZE); + memcpy(&fhp->fh_handle.fh_base, p, NFS_FHSIZE); + fhp->fh_handle.fh_size = NFS_FHSIZE; + + /* FIXME: Look up export pointer here and verify + * Sun Secure RPC if requested */ + return p + (NFS_FHSIZE >> 2); +} + +/* Helper function for NFSv2 ACL code */ +__be32 *nfs2svc_decode_fh(__be32 *p, struct svc_fh *fhp) +{ + return decode_fh(p, fhp); +} + +static __be32 * +encode_fh(__be32 *p, struct svc_fh *fhp) +{ + memcpy(p, &fhp->fh_handle.fh_base, NFS_FHSIZE); + return p + (NFS_FHSIZE>> 2); +} + +/* + * Decode a file name and make sure that the path contains + * no slashes or null bytes. + */ +static __be32 * +decode_filename(__be32 *p, char **namp, unsigned int *lenp) +{ + char *name; + unsigned int i; + + if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXNAMLEN)) != NULL) { + for (i = 0, name = *namp; i < *lenp; i++, name++) { + if (*name == '\0' || *name == '/') + return NULL; + } + } + + return p; +} + +static __be32 * +decode_sattr(__be32 *p, struct iattr *iap, struct user_namespace *userns) +{ + u32 tmp, tmp1; + + iap->ia_valid = 0; + + /* Sun client bug compatibility check: some sun clients seem to + * put 0xffff in the mode field when they mean 0xffffffff. + * Quoting the 4.4BSD nfs server code: Nah nah nah nah na nah. + */ + if ((tmp = ntohl(*p++)) != (u32)-1 && tmp != 0xffff) { + iap->ia_valid |= ATTR_MODE; + iap->ia_mode = tmp; + } + if ((tmp = ntohl(*p++)) != (u32)-1) { + iap->ia_uid = make_kuid(userns, tmp); + if (uid_valid(iap->ia_uid)) + iap->ia_valid |= ATTR_UID; + } + if ((tmp = ntohl(*p++)) != (u32)-1) { + iap->ia_gid = make_kgid(userns, tmp); + if (gid_valid(iap->ia_gid)) + iap->ia_valid |= ATTR_GID; + } + if ((tmp = ntohl(*p++)) != (u32)-1) { + iap->ia_valid |= ATTR_SIZE; + iap->ia_size = tmp; + } + tmp = ntohl(*p++); tmp1 = ntohl(*p++); + if (tmp != (u32)-1 && tmp1 != (u32)-1) { + iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET; + iap->ia_atime.tv_sec = tmp; + iap->ia_atime.tv_nsec = tmp1 * 1000; + } + tmp = ntohl(*p++); tmp1 = ntohl(*p++); + if (tmp != (u32)-1 && tmp1 != (u32)-1) { + iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET; + iap->ia_mtime.tv_sec = tmp; + iap->ia_mtime.tv_nsec = tmp1 * 1000; + /* + * Passing the invalid value useconds=1000000 for mtime + * is a Sun convention for "set both mtime and atime to + * current server time". It's needed to make permissions + * checks for the "touch" program across v2 mounts to + * Solaris and Irix boxes work correctly. See description of + * sattr in section 6.1 of "NFS Illustrated" by + * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5 + */ + if (tmp1 == 1000000) + iap->ia_valid &= ~(ATTR_ATIME_SET|ATTR_MTIME_SET); + } + return p; +} + +static __be32 * +encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp, + struct kstat *stat) +{ + struct user_namespace *userns = nfsd_user_namespace(rqstp); + struct dentry *dentry = fhp->fh_dentry; + int type; + struct timespec64 time; + u32 f; + + type = (stat->mode & S_IFMT); + + *p++ = htonl(nfs_ftypes[type >> 12]); + *p++ = htonl((u32) stat->mode); + *p++ = htonl((u32) stat->nlink); + *p++ = htonl((u32) from_kuid_munged(userns, stat->uid)); + *p++ = htonl((u32) from_kgid_munged(userns, stat->gid)); + + if (S_ISLNK(type) && stat->size > NFS_MAXPATHLEN) { + *p++ = htonl(NFS_MAXPATHLEN); + } else { + *p++ = htonl((u32) stat->size); + } + *p++ = htonl((u32) stat->blksize); + if (S_ISCHR(type) || S_ISBLK(type)) + *p++ = htonl(new_encode_dev(stat->rdev)); + else + *p++ = htonl(0xffffffff); + *p++ = htonl((u32) stat->blocks); + switch (fsid_source(fhp)) { + default: + case FSIDSOURCE_DEV: + *p++ = htonl(new_encode_dev(stat->dev)); + break; + case FSIDSOURCE_FSID: + *p++ = htonl((u32) fhp->fh_export->ex_fsid); + break; + case FSIDSOURCE_UUID: + f = ((u32*)fhp->fh_export->ex_uuid)[0]; + f ^= ((u32*)fhp->fh_export->ex_uuid)[1]; + f ^= ((u32*)fhp->fh_export->ex_uuid)[2]; + f ^= ((u32*)fhp->fh_export->ex_uuid)[3]; + *p++ = htonl(f); + break; + } + *p++ = htonl((u32) stat->ino); + *p++ = htonl((u32) stat->atime.tv_sec); + *p++ = htonl(stat->atime.tv_nsec ? stat->atime.tv_nsec / 1000 : 0); + time = stat->mtime; + lease_get_mtime(d_inode(dentry), &time); + *p++ = htonl((u32) time.tv_sec); + *p++ = htonl(time.tv_nsec ? time.tv_nsec / 1000 : 0); + *p++ = htonl((u32) stat->ctime.tv_sec); + *p++ = htonl(stat->ctime.tv_nsec ? stat->ctime.tv_nsec / 1000 : 0); + + return p; +} + +/* Helper function for NFSv2 ACL code */ +__be32 *nfs2svc_encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp, struct kstat *stat) +{ + return encode_fattr(rqstp, p, fhp, stat); +} + +/* + * XDR decode functions + */ +int +nfssvc_decode_void(struct svc_rqst *rqstp, __be32 *p) +{ + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_fhandle *args = rqstp->rq_argp; + + p = decode_fh(p, &args->fh); + if (!p) + return 0; + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_sattrargs *args = rqstp->rq_argp; + + p = decode_fh(p, &args->fh); + if (!p) + return 0; + p = decode_sattr(p, &args->attrs, nfsd_user_namespace(rqstp)); + + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_diropargs *args = rqstp->rq_argp; + + if (!(p = decode_fh(p, &args->fh)) + || !(p = decode_filename(p, &args->name, &args->len))) + return 0; + + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_readargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_readargs *args = rqstp->rq_argp; + unsigned int len; + int v; + p = decode_fh(p, &args->fh); + if (!p) + return 0; + + args->offset = ntohl(*p++); + len = args->count = ntohl(*p++); + p++; /* totalcount - unused */ + + len = min_t(unsigned int, len, NFSSVC_MAXBLKSIZE_V2); + + /* set up somewhere to store response. + * We take pages, put them on reslist and include in iovec + */ + v=0; + while (len > 0) { + struct page *p = *(rqstp->rq_next_page++); + + rqstp->rq_vec[v].iov_base = page_address(p); + rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE); + len -= rqstp->rq_vec[v].iov_len; + v++; + } + args->vlen = v; + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_writeargs *args = rqstp->rq_argp; + unsigned int len, hdr, dlen; + struct kvec *head = rqstp->rq_arg.head; + + p = decode_fh(p, &args->fh); + if (!p) + return 0; + + p++; /* beginoffset */ + args->offset = ntohl(*p++); /* offset */ + p++; /* totalcount */ + len = args->len = ntohl(*p++); + /* + * The protocol specifies a maximum of 8192 bytes. + */ + if (len > NFSSVC_MAXBLKSIZE_V2) + return 0; + + /* + * Check to make sure that we got the right number of + * bytes. + */ + hdr = (void*)p - head->iov_base; + if (hdr > head->iov_len) + return 0; + dlen = head->iov_len + rqstp->rq_arg.page_len - hdr; + + /* + * Round the length of the data which was specified up to + * the next multiple of XDR units and then compare that + * against the length which was actually received. + * Note that when RPCSEC/GSS (for example) is used, the + * data buffer can be padded so dlen might be larger + * than required. It must never be smaller. + */ + if (dlen < XDR_QUADLEN(len)*4) + return 0; + + args->first.iov_base = (void *)p; + args->first.iov_len = head->iov_len - hdr; + return 1; +} + +int +nfssvc_decode_createargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_createargs *args = rqstp->rq_argp; + + if ( !(p = decode_fh(p, &args->fh)) + || !(p = decode_filename(p, &args->name, &args->len))) + return 0; + p = decode_sattr(p, &args->attrs, nfsd_user_namespace(rqstp)); + + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_renameargs *args = rqstp->rq_argp; + + if (!(p = decode_fh(p, &args->ffh)) + || !(p = decode_filename(p, &args->fname, &args->flen)) + || !(p = decode_fh(p, &args->tfh)) + || !(p = decode_filename(p, &args->tname, &args->tlen))) + return 0; + + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_readlinkargs *args = rqstp->rq_argp; + + p = decode_fh(p, &args->fh); + if (!p) + return 0; + args->buffer = page_address(*(rqstp->rq_next_page++)); + + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_linkargs *args = rqstp->rq_argp; + + if (!(p = decode_fh(p, &args->ffh)) + || !(p = decode_fh(p, &args->tfh)) + || !(p = decode_filename(p, &args->tname, &args->tlen))) + return 0; + + return xdr_argsize_check(rqstp, p); +} + +int +nfssvc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_symlinkargs *args = rqstp->rq_argp; + char *base = (char *)p; + size_t xdrlen; + + if ( !(p = decode_fh(p, &args->ffh)) + || !(p = decode_filename(p, &args->fname, &args->flen))) + return 0; + + args->tlen = ntohl(*p++); + if (args->tlen == 0) + return 0; + + args->first.iov_base = p; + args->first.iov_len = rqstp->rq_arg.head[0].iov_len; + args->first.iov_len -= (char *)p - base; + + /* This request is never larger than a page. Therefore, + * transport will deliver either: + * 1. pathname in the pagelist -> sattr is in the tail. + * 2. everything in the head buffer -> sattr is in the head. + */ + if (rqstp->rq_arg.page_len) { + if (args->tlen != rqstp->rq_arg.page_len) + return 0; + p = rqstp->rq_arg.tail[0].iov_base; + } else { + xdrlen = XDR_QUADLEN(args->tlen); + if (xdrlen > args->first.iov_len - (8 * sizeof(__be32))) + return 0; + p += xdrlen; + } + decode_sattr(p, &args->attrs, nfsd_user_namespace(rqstp)); + + return 1; +} + +int +nfssvc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_readdirargs *args = rqstp->rq_argp; + + p = decode_fh(p, &args->fh); + if (!p) + return 0; + args->cookie = ntohl(*p++); + args->count = ntohl(*p++); + args->count = min_t(u32, args->count, PAGE_SIZE); + args->buffer = page_address(*(rqstp->rq_next_page++)); + + return xdr_argsize_check(rqstp, p); +} + +/* + * XDR encode functions + */ +int +nfssvc_encode_void(struct svc_rqst *rqstp, __be32 *p) +{ + return xdr_ressize_check(rqstp, p); +} + +int +nfssvc_encode_stat(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_stat *resp = rqstp->rq_resp; + + *p++ = resp->status; + return xdr_ressize_check(rqstp, p); +} + +int +nfssvc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_attrstat *resp = rqstp->rq_resp; + + *p++ = resp->status; + if (resp->status != nfs_ok) + goto out; + p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); +out: + return xdr_ressize_check(rqstp, p); +} + +int +nfssvc_encode_diropres(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_diropres *resp = rqstp->rq_resp; + + *p++ = resp->status; + if (resp->status != nfs_ok) + goto out; + p = encode_fh(p, &resp->fh); + p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); +out: + return xdr_ressize_check(rqstp, p); +} + +int +nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_readlinkres *resp = rqstp->rq_resp; + + *p++ = resp->status; + if (resp->status != nfs_ok) + return xdr_ressize_check(rqstp, p); + + *p++ = htonl(resp->len); + xdr_ressize_check(rqstp, p); + rqstp->rq_res.page_len = resp->len; + if (resp->len & 3) { + /* need to pad the tail */ + rqstp->rq_res.tail[0].iov_base = p; + *p = 0; + rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3); + } + return 1; +} + +int +nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_readres *resp = rqstp->rq_resp; + + *p++ = resp->status; + if (resp->status != nfs_ok) + return xdr_ressize_check(rqstp, p); + + p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); + *p++ = htonl(resp->count); + xdr_ressize_check(rqstp, p); + + /* now update rqstp->rq_res to reflect data as well */ + rqstp->rq_res.page_len = resp->count; + if (resp->count & 3) { + /* need to pad the tail */ + rqstp->rq_res.tail[0].iov_base = p; + *p = 0; + rqstp->rq_res.tail[0].iov_len = 4 - (resp->count&3); + } + return 1; +} + +int +nfssvc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_readdirres *resp = rqstp->rq_resp; + + *p++ = resp->status; + if (resp->status != nfs_ok) + return xdr_ressize_check(rqstp, p); + + xdr_ressize_check(rqstp, p); + p = resp->buffer; + *p++ = 0; /* no more entries */ + *p++ = htonl((resp->common.err == nfserr_eof)); + rqstp->rq_res.page_len = (((unsigned long)p-1) & ~PAGE_MASK)+1; + + return 1; +} + +int +nfssvc_encode_statfsres(struct svc_rqst *rqstp, __be32 *p) +{ + struct nfsd_statfsres *resp = rqstp->rq_resp; + struct kstatfs *stat = &resp->stats; + + *p++ = resp->status; + if (resp->status != nfs_ok) + return xdr_ressize_check(rqstp, p); + + *p++ = htonl(NFSSVC_MAXBLKSIZE_V2); /* max transfer size */ + *p++ = htonl(stat->f_bsize); + *p++ = htonl(stat->f_blocks); + *p++ = htonl(stat->f_bfree); + *p++ = htonl(stat->f_bavail); + return xdr_ressize_check(rqstp, p); +} + +int +nfssvc_encode_entry(void *ccdv, const char *name, + int namlen, loff_t offset, u64 ino, unsigned int d_type) +{ + struct readdir_cd *ccd = ccdv; + struct nfsd_readdirres *cd = container_of(ccd, struct nfsd_readdirres, common); + __be32 *p = cd->buffer; + int buflen, slen; + + /* + dprintk("nfsd: entry(%.*s off %ld ino %ld)\n", + namlen, name, offset, ino); + */ + + if (offset > ~((u32) 0)) { + cd->common.err = nfserr_fbig; + return -EINVAL; + } + if (cd->offset) + *cd->offset = htonl(offset); + + /* truncate filename */ + namlen = min(namlen, NFS2_MAXNAMLEN); + slen = XDR_QUADLEN(namlen); + + if ((buflen = cd->buflen - slen - 4) < 0) { + cd->common.err = nfserr_toosmall; + return -EINVAL; + } + if (ino > ~((u32) 0)) { + cd->common.err = nfserr_fbig; + return -EINVAL; + } + *p++ = xdr_one; /* mark entry present */ + *p++ = htonl((u32) ino); /* file id */ + p = xdr_encode_array(p, name, namlen);/* name length & name */ + cd->offset = p; /* remember pointer */ + *p++ = htonl(~0U); /* offset of next entry */ + + cd->buflen = buflen; + cd->buffer = p; + cd->common.err = nfs_ok; + return 0; +} + +/* + * XDR release functions + */ +void nfssvc_release_attrstat(struct svc_rqst *rqstp) +{ + struct nfsd_attrstat *resp = rqstp->rq_resp; + + fh_put(&resp->fh); +} + +void nfssvc_release_diropres(struct svc_rqst *rqstp) +{ + struct nfsd_diropres *resp = rqstp->rq_resp; + + fh_put(&resp->fh); +} + +void nfssvc_release_readres(struct svc_rqst *rqstp) +{ + struct nfsd_readres *resp = rqstp->rq_resp; + + fh_put(&resp->fh); +} |