1 files changed, 295 insertions, 42 deletions

diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c
index ca905a5bb1ba..38ef9eaec407 100644
--- a/fs/nfs/mount_clnt.c
+++ b/fs/nfs/mount_clnt.c
@@ -20,8 +20,116 @@
 # define NFSDBG_FACILITY	NFSDBG_MOUNT
 #endif
 
+/*
+ * Defined by RFC 1094, section A.3; and RFC 1813, section 5.1.4
+ */
+#define MNTPATHLEN		(1024)
+
+/*
+ * XDR data type sizes
+ */
+#define encode_dirpath_sz	(1 + XDR_QUADLEN(MNTPATHLEN))
+#define MNT_status_sz		(1)
+#define MNT_fhs_status_sz	(1)
+#define MNT_fhandle_sz		XDR_QUADLEN(NFS2_FHSIZE)
+#define MNT_fhandle3_sz		(1 + XDR_QUADLEN(NFS3_FHSIZE))
+#define MNT_authflav3_sz	(1 + NFS_MAX_SECFLAVORS)
+
+/*
+ * XDR argument and result sizes
+ */
+#define MNT_enc_dirpath_sz	encode_dirpath_sz
+#define MNT_dec_mountres_sz	(MNT_status_sz + MNT_fhandle_sz)
+#define MNT_dec_mountres3_sz	(MNT_status_sz + MNT_fhandle_sz + \
+				 MNT_authflav3_sz)
+
+/*
+ * Defined by RFC 1094, section A.5
+ */
+enum {
+	MOUNTPROC_NULL		= 0,
+	MOUNTPROC_MNT		= 1,
+	MOUNTPROC_DUMP		= 2,
+	MOUNTPROC_UMNT		= 3,
+	MOUNTPROC_UMNTALL	= 4,
+	MOUNTPROC_EXPORT	= 5,
+};
+
+/*
+ * Defined by RFC 1813, section 5.2
+ */
+enum {
+	MOUNTPROC3_NULL		= 0,
+	MOUNTPROC3_MNT		= 1,
+	MOUNTPROC3_DUMP		= 2,
+	MOUNTPROC3_UMNT		= 3,
+	MOUNTPROC3_UMNTALL	= 4,
+	MOUNTPROC3_EXPORT	= 5,
+};
+
 static struct rpc_program	mnt_program;
 
+/*
+ * Defined by OpenGroup XNFS Version 3W, chapter 8
+ */
+enum mountstat {
+	MNT_OK			= 0,
+	MNT_EPERM		= 1,
+	MNT_ENOENT		= 2,
+	MNT_EACCES		= 13,
+	MNT_EINVAL		= 22,
+};
+
+static struct {
+	u32 status;
+	int errno;
+} mnt_errtbl[] = {
+	{ .status = MNT_OK,			.errno = 0,		},
+	{ .status = MNT_EPERM,			.errno = -EPERM,	},
+	{ .status = MNT_ENOENT,			.errno = -ENOENT,	},
+	{ .status = MNT_EACCES,			.errno = -EACCES,	},
+	{ .status = MNT_EINVAL,			.errno = -EINVAL,	},
+};
+
+/*
+ * Defined by RFC 1813, section 5.1.5
+ */
+enum mountstat3 {
+	MNT3_OK			= 0,		/* no error */
+	MNT3ERR_PERM		= 1,		/* Not owner */
+	MNT3ERR_NOENT		= 2,		/* No such file or directory */
+	MNT3ERR_IO		= 5,		/* I/O error */
+	MNT3ERR_ACCES		= 13,		/* Permission denied */
+	MNT3ERR_NOTDIR		= 20,		/* Not a directory */
+	MNT3ERR_INVAL		= 22,		/* Invalid argument */
+	MNT3ERR_NAMETOOLONG	= 63,		/* Filename too long */
+	MNT3ERR_NOTSUPP		= 10004,	/* Operation not supported */
+	MNT3ERR_SERVERFAULT	= 10006,	/* A failure on the server */
+};
+
+static struct {
+	u32 status;
+	int errno;
+} mnt3_errtbl[] = {
+	{ .status = MNT3_OK,			.errno = 0,		},
+	{ .status = MNT3ERR_PERM,		.errno = -EPERM,	},
+	{ .status = MNT3ERR_NOENT,		.errno = -ENOENT,	},
+	{ .status = MNT3ERR_IO,			.errno = -EIO,		},
+	{ .status = MNT3ERR_ACCES,		.errno = -EACCES,	},
+	{ .status = MNT3ERR_NOTDIR,		.errno = -ENOTDIR,	},
+	{ .status = MNT3ERR_INVAL,		.errno = -EINVAL,	},
+	{ .status = MNT3ERR_NAMETOOLONG,	.errno = -ENAMETOOLONG,	},
+	{ .status = MNT3ERR_NOTSUPP,		.errno = -ENOTSUPP,	},
+	{ .status = MNT3ERR_SERVERFAULT,	.errno = -ESERVERFAULT,	},
+};
+
+struct mountres {
+	int errno;
+	struct nfs_fh *fh;
+	unsigned int *auth_count;
+	rpc_authflavor_t *auth_flavors;
+};
+
 struct mnt_fhstatus {
 	u32 status;
 	struct nfs_fh *fh;
@@ -35,8 +143,10 @@ struct mnt_fhstatus {
  */
 int nfs_mount(struct nfs_mount_request *info)
 {
-	struct mnt_fhstatus	result = {
-		.fh		= info->fh
+	struct mountres	result = {
+		.fh		= info->fh,
+		.auth_count	= info->auth_flav_len,
+		.auth_flavors	= info->auth_flavs,
 	};
 	struct rpc_message msg	= {
 		.rpc_argp	= info->dirpath,
@@ -68,14 +178,14 @@ int nfs_mount(struct nfs_mount_request *info)
 	if (info->version == NFS_MNT3_VERSION)
 		msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC3_MNT];
 	else
-		msg.rpc_proc = &mnt_clnt->cl_procinfo[MNTPROC_MNT];
+		msg.rpc_proc = &mnt_clnt->cl_procinfo[MOUNTPROC_MNT];
 
 	status = rpc_call_sync(mnt_clnt, &msg, 0);
 	rpc_shutdown_client(mnt_clnt);
 
 	if (status < 0)
 		goto out_call_err;
-	if (result.status != 0)
+	if (result.errno != 0)
 		goto out_mnt_err;
 
 	dprintk("NFS: MNT request succeeded\n");
@@ -86,72 +196,215 @@ out:
 
 out_clnt_err:
 	status = PTR_ERR(mnt_clnt);
-	dprintk("NFS: failed to create RPC client, status=%d\n", status);
+	dprintk("NFS: failed to create MNT RPC client, status=%d\n", status);
 	goto out;
 
 out_call_err:
-	dprintk("NFS: failed to start MNT request, status=%d\n", status);
+	dprintk("NFS: MNT request failed, status=%d\n", status);
 	goto out;
 
 out_mnt_err:
-	dprintk("NFS: MNT server returned result %d\n", result.status);
-	status = nfs_stat_to_errno(result.status);
+	dprintk("NFS: MNT server returned result %d\n", result.errno);
+	status = result.errno;
 	goto out;
 }
 
 /*
  * XDR encode/decode functions for MOUNT
  */
-static int xdr_encode_dirpath(struct rpc_rqst *req, __be32 *p,
-			      const char *path)
+
+static int encode_mntdirpath(struct xdr_stream *xdr, const char *pathname)
+{
+	const u32 pathname_len = strlen(pathname);
+	__be32 *p;
+
+	if (unlikely(pathname_len > MNTPATHLEN))
+		return -EIO;
+
+	p = xdr_reserve_space(xdr, sizeof(u32) + pathname_len);
+	if (unlikely(p == NULL))
+		return -EIO;
+	xdr_encode_opaque(p, pathname, pathname_len);
+
+	return 0;
+}
+
+static int mnt_enc_dirpath(struct rpc_rqst *req, __be32 *p,
+			   const char *dirpath)
+{
+	struct xdr_stream xdr;
+
+	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+	return encode_mntdirpath(&xdr, dirpath);
+}
+
+/*
+ * RFC 1094: "A non-zero status indicates some sort of error.  In this
+ * case, the status is a UNIX error number."  This can be problematic
+ * if the server and client use different errno values for the same
+ * error.
+ *
+ * However, the OpenGroup XNFS spec provides a simple mapping that is
+ * independent of local errno values on the server and the client.
+ */
+static int decode_status(struct xdr_stream *xdr, struct mountres *res)
 {
-	p = xdr_encode_string(p, path);
+	unsigned int i;
+	u32 status;
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, sizeof(status));
+	if (unlikely(p == NULL))
+		return -EIO;
+	status = ntohl(*p);
 
-	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
+	for (i = 0; i <= ARRAY_SIZE(mnt_errtbl); i++) {
+		if (mnt_errtbl[i].status == status) {
+			res->errno = mnt_errtbl[i].errno;
+			return 0;
+		}
+	}
+
+	dprintk("NFS: unrecognized MNT status code: %u\n", status);
+	res->errno = -EACCES;
 	return 0;
 }
 
-static int xdr_decode_fhstatus(struct rpc_rqst *req, __be32 *p,
-			       struct mnt_fhstatus *res)
+static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res)
 {
 	struct nfs_fh *fh = res->fh;
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, NFS2_FHSIZE);
+	if (unlikely(p == NULL))
+		return -EIO;
+
+	fh->size = NFS2_FHSIZE;
+	memcpy(fh->data, p, NFS2_FHSIZE);
+	return 0;
+}
+
+static int mnt_dec_mountres(struct rpc_rqst *req, __be32 *p,
+			    struct mountres *res)
+{
+	struct xdr_stream xdr;
+	int status;
+
+	xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
+
+	status = decode_status(&xdr, res);
+	if (unlikely(status != 0 || res->errno != 0))
+		return status;
+	return decode_fhandle(&xdr, res);
+}
+
+static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res)
+{
+	unsigned int i;
+	u32 status;
+	__be32 *p;
 
-	if ((res->status = ntohl(*p++)) == 0) {
-		fh->size = NFS2_FHSIZE;
-		memcpy(fh->data, p, NFS2_FHSIZE);
+	p = xdr_inline_decode(xdr, sizeof(status));
+	if (unlikely(p == NULL))
+		return -EIO;
+	status = ntohl(*p);
+
+	for (i = 0; i <= ARRAY_SIZE(mnt3_errtbl); i++) {
+		if (mnt3_errtbl[i].status == status) {
+			res->errno = mnt3_errtbl[i].errno;
+			return 0;
+		}
 	}
+
+	dprintk("NFS: unrecognized MNT3 status code: %u\n", status);
+	res->errno = -EACCES;
 	return 0;
 }
 
-static int xdr_decode_fhstatus3(struct rpc_rqst *req, __be32 *p,
-				struct mnt_fhstatus *res)
+static int decode_fhandle3(struct xdr_stream *xdr, struct mountres *res)
 {
 	struct nfs_fh *fh = res->fh;
-	unsigned size;
-
-	if ((res->status = ntohl(*p++)) == 0) {
-		size = ntohl(*p++);
-		if (size <= NFS3_FHSIZE && size != 0) {
-			fh->size = size;
-			memcpy(fh->data, p, size);
-		} else
-			res->status = -EBADHANDLE;
+	u32 size;
+	__be32 *p;
+
+	p = xdr_inline_decode(xdr, sizeof(size));
+	if (unlikely(p == NULL))
+		return -EIO;
+
+	size = ntohl(*p++);
+	if (size > NFS3_FHSIZE || size == 0)
+		return -EIO;
+
+	p = xdr_inline_decode(xdr, size);
+	if (unlikely(p == NULL))
+		return -EIO;
+
+	fh->size = size;
+	memcpy(fh->data, p, size);
+	return 0;
+}
+
+static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res)
+{
+	rpc_authflavor_t *flavors = res->auth_flavors;
+	unsigned int *count = res->auth_count;
+	u32 entries, i;
+	__be32 *p;
+
+	if (*count == 0)
+		return 0;
+
+	p = xdr_inline_decode(xdr, sizeof(entries));
+	if (unlikely(p == NULL))
+		return -EIO;
+	entries = ntohl(*p);
+	dprintk("NFS: received %u auth flavors\n", entries);
+	if (entries > NFS_MAX_SECFLAVORS)
+		entries = NFS_MAX_SECFLAVORS;
+
+	p = xdr_inline_decode(xdr, sizeof(u32) * entries);
+	if (unlikely(p == NULL))
+		return -EIO;
+
+	if (entries > *count)
+		entries = *count;
+
+	for (i = 0; i < entries; i++) {
+		flavors[i] = ntohl(*p++);
+		dprintk("NFS:\tflavor %u: %d\n", i, flavors[i]);
 	}
+	*count = i;
+
 	return 0;
 }
 
-#define MNT_dirpath_sz		(1 + 256)
-#define MNT_fhstatus_sz		(1 + 8)
-#define MNT_fhstatus3_sz	(1 + 16)
+static int mnt_dec_mountres3(struct rpc_rqst *req, __be32 *p,
+			     struct mountres *res)
+{
+	struct xdr_stream xdr;
+	int status;
+
+	xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
+
+	status = decode_fhs_status(&xdr, res);
+	if (unlikely(status != 0 || res->errno != 0))
+		return status;
+	status = decode_fhandle3(&xdr, res);
+	if (unlikely(status != 0)) {
+		res->errno = -EBADHANDLE;
+		return 0;
+	}
+	return decode_auth_flavors(&xdr, res);
+}
 
 static struct rpc_procinfo mnt_procedures[] = {
-	[MNTPROC_MNT] = {
-		.p_proc		= MNTPROC_MNT,
-		.p_encode	= (kxdrproc_t) xdr_encode_dirpath,
-		.p_decode	= (kxdrproc_t) xdr_decode_fhstatus,
-		.p_arglen	= MNT_dirpath_sz,
-		.p_replen	= MNT_fhstatus_sz,
-		.p_statidx	= MNTPROC_MNT,
+	[MOUNTPROC_MNT] = {
+		.p_proc		= MOUNTPROC_MNT,
+		.p_encode	= (kxdrproc_t)mnt_enc_dirpath,
+		.p_decode	= (kxdrproc_t)mnt_dec_mountres,
+		.p_arglen	= MNT_enc_dirpath_sz,
+		.p_replen	= MNT_dec_mountres_sz,
+		.p_statidx	= MOUNTPROC_MNT,
 		.p_name		= "MOUNT",
 	},
 };
@@ -159,10 +412,10 @@ static struct rpc_procinfo mnt_procedures[] = {
 static struct rpc_procinfo mnt3_procedures[] = {
 	[MOUNTPROC3_MNT] = {
 		.p_proc		= MOUNTPROC3_MNT,
-		.p_encode	= (kxdrproc_t) xdr_encode_dirpath,
-		.p_decode	= (kxdrproc_t) xdr_decode_fhstatus3,
-		.p_arglen	= MNT_dirpath_sz,
-		.p_replen	= MNT_fhstatus3_sz,
+		.p_encode	= (kxdrproc_t)mnt_enc_dirpath,
+		.p_decode	= (kxdrproc_t)mnt_dec_mountres3,
+		.p_arglen	= MNT_enc_dirpath_sz,
+		.p_replen	= MNT_dec_mountres3_sz,
 		.p_statidx	= MOUNTPROC3_MNT,
 		.p_name		= "MOUNT",
 	},