2011-04-19 20:48:35

by Anna Schumaker

[permalink] [raw]
Subject: [PATCH v2] NFS: Add SECINFO_NO_NAME procedure

From: Bryan Schumaker <[email protected]>

If the client is using NFS v4.1, then we can use SECINFO_NO_NAME to find
the secflavor for the initial mount. If the server doesn't support
SECINFO_NO_NAME then I fall back on the "guess and check" method used
for v4.0 mounts.

Signed-off-by: Bryan Schumaker <[email protected]>
---
fs/nfs/internal.h | 3 ++
fs/nfs/namespace.c | 2 +-
fs/nfs/nfs4_fs.h | 2 +
fs/nfs/nfs4proc.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++-
fs/nfs/nfs4xdr.c | 66 +++++++++++++++++++++++++++++++++++++
include/linux/nfs4.h | 1 +
include/linux/nfs_xdr.h | 8 ++++
7 files changed, 164 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index ce118ce..361a3a3 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -266,6 +266,9 @@ extern void nfs_sb_deactive(struct super_block *sb);
extern char *nfs_path(char **p, struct dentry *dentry,
char *buffer, ssize_t buflen);
extern struct vfsmount *nfs_d_automount(struct path *path);
+#ifdef CONFIG_NFS_V4
+rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *);
+#endif

/* getroot.c */
extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 1f063ba..8102391 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -119,7 +119,7 @@ Elong:
}

#ifdef CONFIG_NFS_V4
-static rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *flavors)
+rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *flavors)
{
struct gss_api_mech *mech;
struct xdr_netobj oid;
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index e1c261d..9f6bfa6 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -65,6 +65,8 @@ struct nfs4_minor_version_ops {
int cache_reply);
int (*validate_stateid)(struct nfs_delegation *,
const nfs4_stateid *);
+ int (*find_root_sec)(struct nfs_server *, struct nfs_fh *,
+ struct nfs_fsinfo *);
const struct nfs4_state_recovery_ops *reboot_recovery_ops;
const struct nfs4_state_recovery_ops *nograce_recovery_ops;
const struct nfs4_state_maintenance_ops *state_renewal_ops;
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 628e35f..a9c00f5 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2248,13 +2248,14 @@ static int nfs4_find_root_sec(struct nfs_server *server, struct nfs_fh *fhandle,
static int nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
struct nfs_fsinfo *info)
{
+ int minor_version = server->nfs_client->cl_minorversion;
int status = nfs4_lookup_root(server, fhandle, info);
if ((status == -NFS4ERR_WRONGSEC) && !(server->flags & NFS_MOUNT_SECFLAVOUR))
/*
* A status of -NFS4ERR_WRONGSEC will be mapped to -EPERM
* by nfs4_map_errors() as this function exits.
*/
- status = nfs4_find_root_sec(server, fhandle, info);
+ status = nfs_v4_minor_ops[minor_version]->find_root_sec(server, fhandle, info);
if (status == 0)
status = nfs4_server_capabilities(server, fhandle);
if (status == 0)
@@ -5821,6 +5822,85 @@ out:
rpc_put_task(task);
return status;
}
+
+static int
+_nfs41_proc_secinfo_no_name(struct nfs_server *server, struct nfs_fh *fhandle,
+ struct nfs_fsinfo *info, struct nfs4_secinfo_flavors *flavors)
+{
+ struct nfs41_secinfo_no_name_args args = {
+ .style = SECINFO_STYLE_CURRENT_FH,
+ };
+ struct nfs4_secinfo_res res = {
+ .flavors = flavors,
+ };
+ struct rpc_message msg = {
+ .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SECINFO_NO_NAME],
+ .rpc_argp = &args,
+ .rpc_resp = &res,
+ };
+ return nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 0);
+}
+
+static int
+nfs41_proc_secinfo_no_name(struct nfs_server *server, struct nfs_fh *fhandle,
+ struct nfs_fsinfo *info, struct nfs4_secinfo_flavors *flavors)
+{
+ struct nfs4_exception exception = { };
+ int err;
+ do {
+ err = _nfs41_proc_secinfo_no_name(server, fhandle, info, flavors);
+ switch (err) {
+ case 0:
+ case -NFS4ERR_WRONGSEC:
+ case -NFS4ERR_NOTSUPP:
+ break;
+ default:
+ err = nfs4_handle_exception(server, err, &exception);
+ }
+ } while (exception.retry);
+ return err;
+}
+
+static int
+nfs41_find_root_sec(struct nfs_server *server, struct nfs_fh *fhandle,
+ struct nfs_fsinfo *info)
+{
+ int err;
+ struct page *page;
+ rpc_authflavor_t flavor;
+ struct nfs4_secinfo_flavors *flavors;
+
+ page = alloc_page(GFP_KERNEL);
+ if (!page) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ flavors = page_address(page);
+ err = nfs41_proc_secinfo_no_name(server, fhandle, info, flavors);
+
+ /*
+ * Fall back on "guess and check" method if
+ * the server doesn't support SECINFO_NO_NAME
+ */
+ if (err == -NFS4ERR_WRONGSEC || err == -NFS4ERR_NOTSUPP) {
+ err = nfs4_find_root_sec(server, fhandle, info);
+ goto out_freepage;
+ }
+ if (err)
+ goto out_freepage;
+
+ flavor = nfs_find_best_sec(flavors);
+ if (err == 0)
+ err = nfs4_lookup_root_sec(server, fhandle, info, flavor);
+
+out_freepage:
+ put_page(page);
+ if (err == -EACCES)
+ return -EPERM;
+out:
+ return err;
+}
#endif /* CONFIG_NFS_V4_1 */

struct nfs4_state_recovery_ops nfs40_reboot_recovery_ops = {
@@ -5882,6 +5962,7 @@ static const struct nfs4_minor_version_ops nfs_v4_0_minor_ops = {
.minor_version = 0,
.call_sync = _nfs4_call_sync,
.validate_stateid = nfs4_validate_delegation_stateid,
+ .find_root_sec = nfs4_find_root_sec,
.reboot_recovery_ops = &nfs40_reboot_recovery_ops,
.nograce_recovery_ops = &nfs40_nograce_recovery_ops,
.state_renewal_ops = &nfs40_state_renewal_ops,
@@ -5892,6 +5973,7 @@ static const struct nfs4_minor_version_ops nfs_v4_1_minor_ops = {
.minor_version = 1,
.call_sync = _nfs4_call_sync_session,
.validate_stateid = nfs41_validate_delegation_stateid,
+ .find_root_sec = nfs41_find_root_sec,
.reboot_recovery_ops = &nfs41_reboot_recovery_ops,
.nograce_recovery_ops = &nfs41_nograce_recovery_ops,
.state_renewal_ops = &nfs41_state_renewal_ops,
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index ba952bd..00952b2 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -338,6 +338,8 @@ static int nfs4_stat_to_errno(int);
1 /* layoutupdate4 layout type */ + \
1 /* NULL filelayout layoutupdate4 payload */)
#define decode_layoutcommit_maxsz (op_decode_hdr_maxsz + 3)
+#define encode_secinfo_no_name_maxsz (op_encode_hdr_maxsz + 4)
+#define decode_secinfo_no_name_maxsz decode_secinfo_maxsz

#else /* CONFIG_NFS_V4_1 */
#define encode_sequence_maxsz 0
@@ -760,6 +762,12 @@ static int nfs4_stat_to_errno(int);
decode_putfh_maxsz + \
decode_layoutcommit_maxsz + \
decode_getattr_maxsz)
+#define NFS4_enc_secinfo_no_name_sz (compound_encode_hdr_maxsz + \
+ encode_putrootfh_maxsz +\
+ encode_secinfo_no_name_maxsz)
+#define NFS4_dec_secinfo_no_name_sz (compound_decode_hdr_maxsz + \
+ decode_putrootfh_maxsz + \
+ decode_secinfo_no_name_maxsz)


const u32 nfs41_maxwrite_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
@@ -1890,6 +1898,20 @@ encode_layoutcommit(struct xdr_stream *xdr,
hdr->replen += decode_layoutcommit_maxsz;
return 0;
}
+
+static int
+encode_secinfo_no_name(struct xdr_stream *xdr,
+ const struct nfs41_secinfo_no_name_args *args,
+ struct compound_hdr *hdr)
+{
+ __be32 *p;
+ p = reserve_space(xdr, 8);
+ *p++ = cpu_to_be32(OP_SECINFO_NO_NAME);
+ *p++ = cpu_to_be32(args->style);
+ hdr->nops++;
+ hdr->replen += decode_secinfo_no_name_maxsz;
+ return 0;
+}
#endif /* CONFIG_NFS_V4_1 */

/*
@@ -2723,6 +2745,25 @@ static int nfs4_xdr_enc_layoutcommit(struct rpc_rqst *req,
encode_nops(&hdr);
return 0;
}
+
+/*
+ * Encode SECINFO_NO_NAME request
+ */
+static int nfs4_xdr_enc_secinfo_no_name(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ struct nfs41_secinfo_no_name_args *args)
+{
+ struct compound_hdr hdr = {
+ .minorversion = nfs4_xdr_minorversion(&args->seq_args),
+ };
+
+ encode_compound_hdr(xdr, req, &hdr);
+ encode_sequence(xdr, &args->seq_args, &hdr);
+ encode_putrootfh(xdr, &hdr);
+ encode_secinfo_no_name(xdr, args, &hdr);
+ encode_nops(&hdr);
+ return 0;
+}
#endif /* CONFIG_NFS_V4_1 */

static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
@@ -6348,6 +6389,30 @@ static int nfs4_xdr_dec_layoutcommit(struct rpc_rqst *rqstp,
out:
return status;
}
+
+/*
+ * Decode SECINFO_NO_NAME response
+ */
+static int nfs4_xdr_dec_secinfo_no_name(struct rpc_rqst *rqstp,
+ struct xdr_stream *xdr,
+ struct nfs4_secinfo_res *res)
+{
+ struct compound_hdr hdr;
+ int status;
+
+ status = decode_compound_hdr(xdr, &hdr);
+ if (status)
+ goto out;
+ status = decode_sequence(xdr, &res->seq_res, rqstp);
+ if (status)
+ goto out;
+ status = decode_putrootfh(xdr);
+ if (status)
+ goto out;
+ status = decode_secinfo(xdr, res);
+out:
+ return status;
+}
#endif /* CONFIG_NFS_V4_1 */

/**
@@ -6547,6 +6612,7 @@ struct rpc_procinfo nfs4_procedures[] = {
PROC(GETDEVICEINFO, enc_getdeviceinfo, dec_getdeviceinfo),
PROC(LAYOUTGET, enc_layoutget, dec_layoutget),
PROC(LAYOUTCOMMIT, enc_layoutcommit, dec_layoutcommit),
+ PROC(SECINFO_NO_NAME, enc_secinfo_no_name, dec_secinfo_no_name),
#endif /* CONFIG_NFS_V4_1 */
};

diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 178fafe..7668f25 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -562,6 +562,7 @@ enum {
NFSPROC4_CLNT_LAYOUTGET,
NFSPROC4_CLNT_GETDEVICEINFO,
NFSPROC4_CLNT_LAYOUTCOMMIT,
+ NFSPROC4_CLNT_SECINFO_NO_NAME,
};

/* nfs41 types */
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 78b101e..a8123b7 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1060,6 +1060,14 @@ struct nfs41_reclaim_complete_args {
struct nfs41_reclaim_complete_res {
struct nfs4_sequence_res seq_res;
};
+
+#define SECINFO_STYLE_CURRENT_FH 0
+#define SECINFO_STYLE_PARENT 1
+struct nfs41_secinfo_no_name_args {
+ int style;
+ struct nfs4_sequence_args seq_args;
+};
+
#endif /* CONFIG_NFS_V4_1 */

struct nfs_page;
--
1.7.4.4