NFS: Add secinfo procedure

This patch adds the nfs4 operation secinfo as a
valid nfs rpc operation.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 208 insertions, 0 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 448657456b68..0b8bae119976 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -4639,6 +4639,40 @@ int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,
         return status;
 }
 
+static int _nfs4_proc_secinfo(struct inode *dir, const struct qstr *name, struct nfs4_secinfo_flavors *flavors)
+{
+        int status;
+        struct nfs4_secinfo_arg args = {
+                .dir_fh = NFS_FH(dir),
+                .name   = name,
+        };
+        struct nfs4_secinfo_res res = {
+                .flavors     = flavors,
+        };
+        struct rpc_message msg = {
+                .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SECINFO],
+                .rpc_argp = &args,
+                .rpc_resp = &res,
+        };
+
+        dprintk("NFS call  secinfo %s\n", name->name);
+        status = nfs4_call_sync(NFS_SERVER(dir)->client, NFS_SERVER(dir), &msg, &args.seq_args, &res.seq_res, 0);
+        dprintk("NFS reply  secinfo: %d\n", status);
+        return status;
+}
+
+int nfs4_proc_secinfo(struct inode *dir, const struct qstr *name, struct nfs4_secinfo_flavors *flavors)
+{
+        struct nfs4_exception exception = { };
+        int err;
+        do {
+                err = nfs4_handle_exception(NFS_SERVER(dir),
+                                _nfs4_proc_secinfo(dir, name, flavors),
+                                &exception);
+        } while (exception.retry);
+        return err;
+}
+
 #ifdef CONFIG_NFS_V4_1
 /*
  * Check the exchange flags returned by the server for invalid flags, having
@@ -5756,6 +5790,7 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
         .close_context  = nfs4_close_context,
         .open_context   = nfs4_atomic_open,
         .init_client    = nfs4_init_client,
+        .secinfo        = nfs4_proc_secinfo,
 };
 
 static const struct xattr_handler nfs4_xattr_nfs4_acl_handler = {
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 0cf560f77884..98afcf947aa4 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -46,6 +46,7 @@
 #include <linux/kdev_t.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/msg_prot.h>
+#include <linux/sunrpc/gss_api.h>
 #include <linux/nfs.h>
 #include <linux/nfs4.h>
 #include <linux/nfs_fs.h>
@@ -253,6 +254,8 @@ static int nfs4_stat_to_errno(int);
                                 (encode_getattr_maxsz)
 #define decode_fs_locations_maxsz \
                                 (0)
+#define encode_secinfo_maxsz    (op_encode_hdr_maxsz + nfs4_name_maxsz)
+#define decode_secinfo_maxsz    (op_decode_hdr_maxsz + 4 + (NFS_MAX_SECFLAVORS * (16 + GSS_OID_MAX_LEN)))
 
 #if defined(CONFIG_NFS_V4_1)
 #define NFS4_MAX_MACHINE_NAME_LEN (64)
@@ -676,6 +679,14 @@ static int nfs4_stat_to_errno(int);
                                  decode_putfh_maxsz + \
                                  decode_lookup_maxsz + \
                                  decode_fs_locations_maxsz)
+#define NFS4_enc_secinfo_sz     (compound_encode_hdr_maxsz + \
+                                encode_sequence_maxsz + \
+                                encode_putfh_maxsz + \
+                                encode_secinfo_maxsz)
+#define NFS4_dec_secinfo_sz     (compound_decode_hdr_maxsz + \
+                                decode_sequence_maxsz + \
+                                decode_putfh_maxsz + \
+                                decode_secinfo_maxsz)
 #if defined(CONFIG_NFS_V4_1)
 #define NFS4_enc_exchange_id_sz \
                                 (compound_encode_hdr_maxsz + \
@@ -1620,6 +1631,18 @@ static void encode_delegreturn(struct xdr_stream *xdr, const nfs4_stateid *state
         hdr->replen += decode_delegreturn_maxsz;
 }
 
+static void encode_secinfo(struct xdr_stream *xdr, const struct qstr *name, struct compound_hdr *hdr)
+{
+        int len = name->len;
+        __be32 *p;
+
+        p = reserve_space(xdr, 8 + len);
+        *p++ = cpu_to_be32(OP_SECINFO);
+        xdr_encode_opaque(p, name->name, len);
+        hdr->nops++;
+        hdr->replen += decode_secinfo_maxsz;
+}
+
 #if defined(CONFIG_NFS_V4_1)
 /* NFSv4.1 operations */
 static void encode_exchange_id(struct xdr_stream *xdr,
@@ -2465,6 +2488,24 @@ static void nfs4_xdr_enc_fs_locations(struct rpc_rqst *req,
         encode_nops(&hdr);
 }
 
+/*
+ * Encode SECINFO request
+ */
+static void nfs4_xdr_enc_secinfo(struct rpc_rqst *req,
+                                struct xdr_stream *xdr,
+                                struct nfs4_secinfo_arg *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_putfh(xdr, args->dir_fh, &hdr);
+        encode_secinfo(xdr, args->name, &hdr);
+        encode_nops(&hdr);
+}
+
 #if defined(CONFIG_NFS_V4_1)
 /*
  * EXCHANGE_ID request
@@ -4680,6 +4721,73 @@ static int decode_delegreturn(struct xdr_stream *xdr)
         return decode_op_hdr(xdr, OP_DELEGRETURN);
 }
 
+static int decode_secinfo_gss(struct xdr_stream *xdr, struct nfs4_secinfo_flavor *flavor)
+{
+        __be32 *p;
+
+        p = xdr_inline_decode(xdr, 4);
+        if (unlikely(!p))
+                goto out_overflow;
+        flavor->gss.sec_oid4.len = be32_to_cpup(p);
+        if (flavor->gss.sec_oid4.len > GSS_OID_MAX_LEN)
+                goto out_err;
+
+        p = xdr_inline_decode(xdr, flavor->gss.sec_oid4.len);
+        if (unlikely(!p))
+                goto out_overflow;
+        memcpy(flavor->gss.sec_oid4.data, p, flavor->gss.sec_oid4.len);
+
+        p = xdr_inline_decode(xdr, 8);
+        if (unlikely(!p))
+                goto out_overflow;
+        flavor->gss.qop4 = be32_to_cpup(p++);
+        flavor->gss.service = be32_to_cpup(p);
+
+        return 0;
+
+out_overflow:
+        print_overflow_msg(__func__, xdr);
+        return -EIO;
+out_err:
+        return -EINVAL;
+}
+
+static int decode_secinfo(struct xdr_stream *xdr, struct nfs4_secinfo_res *res)
+{
+        struct nfs4_secinfo_flavor *sec_flavor;
+        int status;
+        __be32 *p;
+        int i;
+
+        status = decode_op_hdr(xdr, OP_SECINFO);
+        p = xdr_inline_decode(xdr, 4);
+        if (unlikely(!p))
+                goto out_overflow;
+        res->flavors->num_flavors = be32_to_cpup(p);
+
+        for (i = 0; i < res->flavors->num_flavors; i++) {
+                sec_flavor = &res->flavors->flavors[i];
+                if ((char *)&sec_flavor[1] - (char *)res > PAGE_SIZE)
+                        break;
+
+                p = xdr_inline_decode(xdr, 4);
+                if (unlikely(!p))
+                        goto out_overflow;
+                sec_flavor->flavor = be32_to_cpup(p);
+
+                if (sec_flavor->flavor == RPC_AUTH_GSS) {
+                        if (decode_secinfo_gss(xdr, sec_flavor))
+                                break;
+                }
+        }
+
+        return 0;
+
+out_overflow:
+        print_overflow_msg(__func__, xdr);
+        return -EIO;
+}
+
 #if defined(CONFIG_NFS_V4_1)
 static int decode_exchange_id(struct xdr_stream *xdr,
                               struct nfs41_exchange_id_res *res)
@@ -5919,6 +6027,32 @@ out:
         return status;
 }
 
+/*
+ * Decode SECINFO response
+ */
+static int nfs4_xdr_dec_secinfo(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_putfh(xdr);
+        if (status)
+                goto out;
+        status = decode_secinfo(xdr, res);
+        if (status)
+                goto out;
+out:
+        return status;
+}
+
 #if defined(CONFIG_NFS_V4_1)
 /*
  * Decode EXCHANGE_ID response
@@ -6258,6 +6392,7 @@ struct rpc_procinfo	nfs4_procedures[] = {
         PROC(SETACL,            enc_setacl,             dec_setacl),
         PROC(FS_LOCATIONS,      enc_fs_locations,       dec_fs_locations),
         PROC(RELEASE_LOCKOWNER, enc_release_lockowner,  dec_release_lockowner),
+        PROC(SECINFO,           enc_secinfo,            dec_secinfo),
 #if defined(CONFIG_NFS_V4_1)
         PROC(EXCHANGE_ID,       enc_exchange_id,        dec_exchange_id),
         PROC(CREATE_SESSION,    enc_create_session,     dec_create_session),
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 134716e5e350..7e7f6b7e46b1 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -550,6 +550,7 @@ enum {
         NFSPROC4_CLNT_SETACL,
         NFSPROC4_CLNT_FS_LOCATIONS,
         NFSPROC4_CLNT_RELEASE_LOCKOWNER,
+        NFSPROC4_CLNT_SECINFO,
 
         /* nfs41 */
         NFSPROC4_CLNT_EXCHANGE_ID,
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 71ee6799db9b..3f32bf175840 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -3,6 +3,7 @@
 
 #include <linux/nfsacl.h>
 #include <linux/nfs3.h>
+#include <linux/sunrpc/gss_api.h>
 
 /*
  * To change the maximum rsize and wsize supported by the NFS client, adjust
@@ -14,6 +15,9 @@
 #define NFS_DEF_FILE_IO_SIZE    (4096U)
 #define NFS_MIN_FILE_IO_SIZE    (1024U)
 
+/* Forward declaration for NFS v3 */
+struct nfs4_secinfo_flavors;
+
 struct nfs_fsid {
         uint64_t                major;
         uint64_t                minor;
@@ -936,6 +940,38 @@ struct nfs4_fs_locations_res {
         struct nfs4_sequence_res        seq_res;
 };
 
+struct nfs4_secinfo_oid {
+        unsigned int len;
+        char data[GSS_OID_MAX_LEN];
+};
+
+struct nfs4_secinfo_gss {
+        struct nfs4_secinfo_oid sec_oid4;
+        unsigned int qop4;
+        unsigned int service;
+};
+
+struct nfs4_secinfo_flavor {
+        unsigned int            flavor;
+        struct nfs4_secinfo_gss gss;
+};
+
+struct nfs4_secinfo_flavors {
+        unsigned int num_flavors;
+        struct nfs4_secinfo_flavor flavors[0];
+};
+
+struct nfs4_secinfo_arg {
+        const struct nfs_fh             *dir_fh;
+        const struct qstr               *name;
+        struct nfs4_sequence_args       seq_args;
+};
+
+struct nfs4_secinfo_res {
+        struct nfs4_secinfo_flavors     *flavors;
+        struct nfs4_sequence_res        seq_res;
+};
+
 #endif /* CONFIG_NFS_V4 */
 
 struct nfstime4 {
@@ -1118,6 +1154,7 @@ struct nfs_rpc_ops {
                                 struct iattr *iattr);
         int     (*init_client) (struct nfs_client *, const struct rpc_timeout *,
                                 const char *, rpc_authflavor_t, int);
+        int     (*secinfo)(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 };
 
 /*