Merge branch 'rpcsec_gss-from_cel' into linux-next

* rpcsec_gss-from_cel: (21 commits)
  NFS: Retry SETCLIENTID with AUTH_SYS instead of AUTH_NONE
  NFSv4: Don't clear the machine cred when client establish returns EACCES
  NFSv4: Fix issues in nfs4_discover_server_trunking
  NFSv4: Fix the fallback to AUTH_NULL if krb5i is not available
  NFS: Use server-recommended security flavor by default (NFSv3)
  SUNRPC: Don't recognize RPC_AUTH_MAXFLAVOR
  NFS: Use "krb5i" to establish NFSv4 state whenever possible
  NFS: Try AUTH_UNIX when PUTROOTFH gets NFS4ERR_WRONGSEC
  NFS: Use static list of security flavors during root FH lookup recovery
  NFS: Avoid PUTROOTFH when managing leases
  NFS: Clean up nfs4_proc_get_rootfh
  NFS: Handle missing rpc.gssd when looking up root FH
  SUNRPC: Remove EXPORT_SYMBOL_GPL() from GSS mech switch
  SUNRPC: Make gss_mech_get() static
  SUNRPC: Refactor nfsd4_do_encode_secinfo()
  SUNRPC: Consider qop when looking up pseudoflavors
  SUNRPC: Load GSS kernel module by OID
  SUNRPC: Introduce rpcauth_get_pseudoflavor()
  SUNRPC: Define rpcsec_gss_info structure
  NFS: Remove unneeded forward declaration
  ...

fs/nfs/nfs4client.c

@@ -201,7 +201,9 @@ struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 	if (clp->cl_minorversion != 0)
 		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
-	error = nfs_create_rpc_client(clp, timeparms, authflavour);
+	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_GSS_KRB5I);
+	if (error == -EINVAL)
+		error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_NULL);
 	if (error < 0)
 		goto error;
 

fs/nfs/nfs4namespace.c

@@ -134,33 +134,38 @@ static size_t nfs_parse_server_name(char *string, size_t len,
 	return ret;
 }
 
+/**
+ * nfs_find_best_sec - Find a security mechanism supported locally
+ * @flavors: List of security tuples returned by SECINFO procedure
+ *
+ * Return the pseudoflavor of the first security mechanism in
+ * "flavors" that is locally supported.  Return RPC_AUTH_UNIX if
+ * no matching flavor is found in the array.  The "flavors" array
+ * is searched in the order returned from the server, per RFC 3530
+ * recommendation.
+ */
 rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *flavors)
 {
-	struct gss_api_mech *mech;
-	struct xdr_netobj oid;
-	int i;
-	rpc_authflavor_t pseudoflavor = RPC_AUTH_UNIX;
+	rpc_authflavor_t pseudoflavor;
+	struct nfs4_secinfo4 *secinfo;
+	unsigned int i;
 
 	for (i = 0; i < flavors->num_flavors; i++) {
-		struct nfs4_secinfo_flavor *flavor;
-		flavor = &flavors->flavors[i];
-
-		if (flavor->flavor == RPC_AUTH_NULL || flavor->flavor == RPC_AUTH_UNIX) {
-			pseudoflavor = flavor->flavor;
-			break;
-		} else if (flavor->flavor == RPC_AUTH_GSS) {
-			oid.len  = flavor->gss.sec_oid4.len;
-			oid.data = flavor->gss.sec_oid4.data;
-			mech = gss_mech_get_by_OID(&oid);
-			if (!mech)
-				continue;
-			pseudoflavor = gss_svc_to_pseudoflavor(mech, flavor->gss.service);
-			gss_mech_put(mech);
+		secinfo = &flavors->flavors[i];
+
+		switch (secinfo->flavor) {
+		case RPC_AUTH_NULL:
+		case RPC_AUTH_UNIX:
+		case RPC_AUTH_GSS:
+			pseudoflavor = rpcauth_get_pseudoflavor(secinfo->flavor,
+							&secinfo->flavor_info);
+			if (pseudoflavor != RPC_AUTH_MAXFLAVOR)
+				return pseudoflavor;
 			break;
 		}
 	}
 
-	return pseudoflavor;
+	return RPC_AUTH_UNIX;
 }
 
 static rpc_authflavor_t nfs4_negotiate_security(struct inode *inode, struct qstr *name)

fs/nfs/nfs4proc.c

@@ -2547,7 +2547,7 @@ static int nfs4_lookup_root_sec(struct nfs_server *server, struct nfs_fh *fhandl
 
 	auth = rpcauth_create(flavor, server->client);
 	if (IS_ERR(auth)) {
-		ret = -EIO;
+		ret = -EACCES;
 		goto out;
 	}
 	ret = nfs4_lookup_root(server, fhandle, info);
@@ -2555,27 +2555,36 @@ static int nfs4_lookup_root_sec(struct nfs_server *server, struct nfs_fh *fhandl
 	return ret;
 }
 
+/*
+ * Retry pseudoroot lookup with various security flavors.  We do this when:
+ *
+ *   NFSv4.0: the PUTROOTFH operation returns NFS4ERR_WRONGSEC
+ *   NFSv4.1: the server does not support the SECINFO_NO_NAME operation
+ *
+ * Returns zero on success, or a negative NFS4ERR value, or a
+ * negative errno value.
+ */
 static int nfs4_find_root_sec(struct nfs_server *server, struct nfs_fh *fhandle,
 			      struct nfs_fsinfo *info)
 {
-	int i, len, status = 0;
-	rpc_authflavor_t flav_array[NFS_MAX_SECFLAVORS];
-
-	len = rpcauth_list_flavors(flav_array, ARRAY_SIZE(flav_array));
-	if (len < 0)
-		return len;
-
-	for (i = 0; i < len; i++) {
-		/* AUTH_UNIX is the default flavor if none was specified,
-		 * thus has already been tried. */
-		if (flav_array[i] == RPC_AUTH_UNIX)
-			continue;
+	/* Per 3530bis 15.33.5 */
+	static const rpc_authflavor_t flav_array[] = {
+		RPC_AUTH_GSS_KRB5P,
+		RPC_AUTH_GSS_KRB5I,
+		RPC_AUTH_GSS_KRB5,
+		RPC_AUTH_UNIX,			/* courtesy */
+		RPC_AUTH_NULL,
+	};
+	int status = -EPERM;
+	size_t i;
 
+	for (i = 0; i < ARRAY_SIZE(flav_array); i++) {
 		status = nfs4_lookup_root_sec(server, fhandle, info, flav_array[i]);
 		if (status == -NFS4ERR_WRONGSEC || status == -EACCES)
 			continue;
 		break;
 	}
+
 	/*
 	 * -EACCESS could mean that the user doesn't have correct permissions
 	 * to access the mount.  It could also mean that we tried to mount
@@ -2588,24 +2597,36 @@ static int nfs4_find_root_sec(struct nfs_server *server, struct nfs_fh *fhandle,
 	return status;
 }
 
-/*
- * get the file handle for the "/" directory on the server
+static int nfs4_do_find_root_sec(struct nfs_server *server,
+		struct nfs_fh *fhandle, struct nfs_fsinfo *info)
+{
+	int mv = server->nfs_client->cl_minorversion;
+	return nfs_v4_minor_ops[mv]->find_root_sec(server, fhandle, info);
+}
+
+/**
+ * nfs4_proc_get_rootfh - get file handle for server's pseudoroot
+ * @server: initialized nfs_server handle
+ * @fhandle: we fill in the pseudo-fs root file handle
+ * @info: we fill in an FSINFO struct
+ *
+ * Returns zero on success, or a negative errno.
  */
 int nfs4_proc_get_rootfh(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 = nfs_v4_minor_ops[minor_version]->find_root_sec(server, fhandle, info);
+	int status;
+
+	status = nfs4_lookup_root(server, fhandle, info);
+	if ((status == -NFS4ERR_WRONGSEC) &&
+	    !(server->flags & NFS_MOUNT_SECFLAVOUR))
+		status = nfs4_do_find_root_sec(server, fhandle, info);
+
 	if (status == 0)
 		status = nfs4_server_capabilities(server, fhandle);
 	if (status == 0)
 		status = nfs4_do_fsinfo(server, fhandle, info);
+
 	return nfs4_map_errors(status);
 }
 
@@ -3484,12 +3505,21 @@ static int _nfs4_do_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
 static int nfs4_do_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle, struct nfs_fsinfo *fsinfo)
 {
 	struct nfs4_exception exception = { };
+	unsigned long now = jiffies;
 	int err;
 
 	do {
-		err = nfs4_handle_exception(server,
-				_nfs4_do_fsinfo(server, fhandle, fsinfo),
-				&exception);
+		err = _nfs4_do_fsinfo(server, fhandle, fsinfo);
+		if (err == 0) {
+			struct nfs_client *clp = server->nfs_client;
+
+			spin_lock(&clp->cl_lock);
+			clp->cl_lease_time = fsinfo->lease_time * HZ;
+			clp->cl_last_renewal = now;
+			spin_unlock(&clp->cl_lock);
+			break;
+		}
+		err = nfs4_handle_exception(server, err, &exception);
 	} while (exception.retry);
 	return err;
 }
@@ -4330,27 +4360,17 @@ int nfs4_proc_setclientid_confirm(struct nfs_client *clp,
 		struct nfs4_setclientid_res *arg,
 		struct rpc_cred *cred)
 {
-	struct nfs_fsinfo fsinfo;
 	struct rpc_message msg = {
 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SETCLIENTID_CONFIRM],
 		.rpc_argp = arg,
-		.rpc_resp = &fsinfo,
 		.rpc_cred = cred,
 	};
-	unsigned long now;
 	int status;
 
 	dprintk("NFS call  setclientid_confirm auth=%s, (client ID %llx)\n",
 		clp->cl_rpcclient->cl_auth->au_ops->au_name,
 		clp->cl_clientid);
-	now = jiffies;
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
-	if (status == 0) {
-		spin_lock(&clp->cl_lock);
-		clp->cl_lease_time = fsinfo.lease_time * HZ;
-		clp->cl_last_renewal = now;
-		spin_unlock(&clp->cl_lock);
-	}
 	dprintk("NFS reply setclientid_confirm: %d\n", status);
 	return status;
 }

fs/nfs/nfs4state.c

@@ -154,18 +154,6 @@ struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
 	return cred;
 }
 
-static void nfs4_clear_machine_cred(struct nfs_client *clp)
-{
-	struct rpc_cred *cred;
-
-	spin_lock(&clp->cl_lock);
-	cred = clp->cl_machine_cred;
-	clp->cl_machine_cred = NULL;
-	spin_unlock(&clp->cl_lock);
-	if (cred != NULL)
-		put_rpccred(cred);
-}
-
 static struct rpc_cred *
 nfs4_get_renew_cred_server_locked(struct nfs_server *server)
 {
@@ -1776,10 +1764,6 @@ static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
 		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 		return -EPERM;
 	case -EACCES:
-		if (clp->cl_machine_cred == NULL)
-			return -EACCES;
-		/* Handle case where the user hasn't set up machine creds */
-		nfs4_clear_machine_cred(clp);
 	case -NFS4ERR_DELAY:
 	case -ETIMEDOUT:
 	case -EAGAIN:
@@ -1874,31 +1858,18 @@ int nfs4_discover_server_trunking(struct nfs_client *clp,
 {
 	const struct nfs4_state_recovery_ops *ops =
 				clp->cl_mvops->reboot_recovery_ops;
-	rpc_authflavor_t *flavors, flav, save;
 	struct rpc_clnt *clnt;
 	struct rpc_cred *cred;
-	int i, len, status;
+	int i, status;
 
 	dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
 
-	len = NFS_MAX_SECFLAVORS;
-	flavors = kcalloc(len, sizeof(*flavors), GFP_KERNEL);
-	if (flavors == NULL) {
-		status = -ENOMEM;
-		goto out;
-	}
-	len = rpcauth_list_flavors(flavors, len);
-	if (len < 0) {
-		status = len;
-		goto out_free;
-	}
 	clnt = clp->cl_rpcclient;
-	save = clnt->cl_auth->au_flavor;
 	i = 0;
 
 	mutex_lock(&nfs_clid_init_mutex);
-	status  = -ENOENT;
 again:
+	status  = -ENOENT;
 	cred = ops->get_clid_cred(clp);
 	if (cred == NULL)
 		goto out_unlock;
@@ -1908,12 +1879,6 @@ int nfs4_discover_server_trunking(struct nfs_client *clp,
 	switch (status) {
 	case 0:
 		break;
-
-	case -EACCES:
-		if (clp->cl_machine_cred == NULL)
-			break;
-		/* Handle case where the user hasn't set up machine creds */
-		nfs4_clear_machine_cred(clp);
 	case -NFS4ERR_DELAY:
 	case -ETIMEDOUT:
 	case -EAGAIN:
@@ -1922,17 +1887,12 @@ int nfs4_discover_server_trunking(struct nfs_client *clp,
 		dprintk("NFS: %s after status %d, retrying\n",
 			__func__, status);
 		goto again;
-
+	case -EACCES:
+		if (i++)
+			break;
 	case -NFS4ERR_CLID_INUSE:
 	case -NFS4ERR_WRONGSEC:
-		status = -EPERM;
-		if (i >= len)
-			break;
-
-		flav = flavors[i++];
-		if (flav == save)
-			flav = flavors[i++];
-		clnt = rpc_clone_client_set_auth(clnt, flav);
+		clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
 		if (IS_ERR(clnt)) {
 			status = PTR_ERR(clnt);
 			break;
@@ -1948,13 +1908,15 @@ int nfs4_discover_server_trunking(struct nfs_client *clp,
 	case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
 				 * in nfs4_exchange_id */
 		status = -EKEYEXPIRED;
+		break;
+	default:
+		pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
+				__func__, status);
+		status = -EIO;
 	}
 
 out_unlock:
 	mutex_unlock(&nfs_clid_init_mutex);
-out_free:
-	kfree(flavors);
-out:
 	dprintk("NFS: %s: status = %d\n", __func__, status);
 	return status;
 }

fs/nfs/nfs4super.c

@@ -252,6 +252,8 @@ struct dentry *nfs4_try_mount(int flags, const char *dev_name,
 
 	dfprintk(MOUNT, "--> nfs4_try_mount()\n");
 
+	if (data->auth_flavors[0] == RPC_AUTH_MAXFLAVOR)
+		data->auth_flavors[0] = RPC_AUTH_UNIX;
 	export_path = data->nfs_server.export_path;
 	data->nfs_server.export_path = "/";
 	root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info,

fs/nfs/nfs4xdr.c

@@ -530,14 +530,10 @@ static int nfs4_stat_to_errno(int);
 				decode_setclientid_maxsz)
 #define NFS4_enc_setclientid_confirm_sz \
 				(compound_encode_hdr_maxsz + \
-				encode_setclientid_confirm_maxsz + \
-				encode_putrootfh_maxsz + \
-				encode_fsinfo_maxsz)
+				encode_setclientid_confirm_maxsz)
 #define NFS4_dec_setclientid_confirm_sz \
 				(compound_decode_hdr_maxsz + \
-				decode_setclientid_confirm_maxsz + \
-				decode_putrootfh_maxsz + \
-				decode_fsinfo_maxsz)
+				decode_setclientid_confirm_maxsz)
 #define NFS4_enc_lock_sz        (compound_encode_hdr_maxsz + \
 				encode_sequence_maxsz + \
 				encode_putfh_maxsz + \
@@ -2601,12 +2597,9 @@ static void nfs4_xdr_enc_setclientid_confirm(struct rpc_rqst *req,
 	struct compound_hdr hdr = {
 		.nops	= 0,
 	};
-	const u32 lease_bitmap[3] = { FATTR4_WORD0_LEASE_TIME };
 
 	encode_compound_hdr(xdr, req, &hdr);
 	encode_setclientid_confirm(xdr, arg, &hdr);
-	encode_putrootfh(xdr, &hdr);
-	encode_fsinfo(xdr, lease_bitmap, &hdr);
 	encode_nops(&hdr);
 }
 
@@ -5198,27 +5191,30 @@ 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)
+static int decode_secinfo_gss(struct xdr_stream *xdr,
+			      struct nfs4_secinfo4 *flavor)
 {
+	u32 oid_len;
 	__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)
+	oid_len = be32_to_cpup(p);
+	if (oid_len > GSS_OID_MAX_LEN)
 		goto out_err;
 
-	p = xdr_inline_decode(xdr, flavor->gss.sec_oid4.len);
+	p = xdr_inline_decode(xdr, oid_len);
 	if (unlikely(!p))
 		goto out_overflow;
-	memcpy(flavor->gss.sec_oid4.data, p, flavor->gss.sec_oid4.len);
+	memcpy(flavor->flavor_info.oid.data, p, oid_len);
+	flavor->flavor_info.oid.len = oid_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);
+	flavor->flavor_info.qop = be32_to_cpup(p++);
+	flavor->flavor_info.service = be32_to_cpup(p);
 
 	return 0;
 
@@ -5231,10 +5227,10 @@ static int decode_secinfo_gss(struct xdr_stream *xdr, struct nfs4_secinfo_flavor
 
 static int decode_secinfo_common(struct xdr_stream *xdr, struct nfs4_secinfo_res *res)
 {
-	struct nfs4_secinfo_flavor *sec_flavor;
+	struct nfs4_secinfo4 *sec_flavor;
+	unsigned int i, num_flavors;
 	int status;
 	__be32 *p;
-	int i, num_flavors;
 
 	p = xdr_inline_decode(xdr, 4);
 	if (unlikely(!p))
@@ -6637,8 +6633,7 @@ static int nfs4_xdr_dec_setclientid(struct rpc_rqst *req,
  * Decode SETCLIENTID_CONFIRM response
  */
 static int nfs4_xdr_dec_setclientid_confirm(struct rpc_rqst *req,
-					    struct xdr_stream *xdr,
-					    struct nfs_fsinfo *fsinfo)
+					    struct xdr_stream *xdr)
 {
 	struct compound_hdr hdr;
 	int status;
@@ -6646,10 +6641,6 @@ static int nfs4_xdr_dec_setclientid_confirm(struct rpc_rqst *req,
 	status = decode_compound_hdr(xdr, &hdr);
 	if (!status)
 		status = decode_setclientid_confirm(xdr);
-	if (!status)
-		status = decode_putrootfh(xdr);
-	if (!status)
-		status = decode_fsinfo(xdr, fsinfo);
 	return status;
 }
 

fs/nfs/super.c

@@ -917,7 +917,7 @@ static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 		data->mount_server.port	= NFS_UNSPEC_PORT;
 		data->nfs_server.port	= NFS_UNSPEC_PORT;
 		data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-		data->auth_flavors[0]	= RPC_AUTH_UNIX;
+		data->auth_flavors[0]	= RPC_AUTH_MAXFLAVOR;
 		data->auth_flavor_len	= 1;
 		data->minorversion	= 0;
 		data->need_mount	= true;
@@ -1605,49 +1605,57 @@ static int nfs_parse_mount_options(char *raw,
 }
 
 /*
- * Match the requested auth flavors with the list returned by
- * the server.  Returns zero and sets the mount's authentication
- * flavor on success; returns -EACCES if server does not support
- * the requested flavor.
+ * Select a security flavor for this mount.  The selected flavor
+ * is planted in args->auth_flavors[0].
  */
-static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
-			     struct nfs_mount_request *request)
+static void nfs_select_flavor(struct nfs_parsed_mount_data *args,
+			      struct nfs_mount_request *request)
 {
-	unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
+	unsigned int i, count = *(request->auth_flav_len);
+	rpc_authflavor_t flavor;
+
+	if (args->auth_flavors[0] != RPC_AUTH_MAXFLAVOR)
+		goto out;
+
+	/*
+	 * The NFSv2 MNT operation does not return a flavor list.
+	 */
+	if (args->mount_server.version != NFS_MNT3_VERSION)
+		goto out_default;
 
 	/*
 	 * Certain releases of Linux's mountd return an empty
-	 * flavor list.  To prevent behavioral regression with
-	 * these servers (ie. rejecting mounts that used to
-	 * succeed), revert to pre-2.6.32 behavior (no checking)
-	 * if the returned flavor list is empty.
+	 * flavor list in some cases.
 	 */
-	if (server_authlist_len == 0)
-		return 0;
+	if (count == 0)
+		goto out_default;
 
 	/*
-	 * We avoid sophisticated negotiating here, as there are
-	 * plenty of cases where we can get it wrong, providing
-	 * either too little or too much security.
-	 *
 	 * RFC 2623, section 2.7 suggests we SHOULD prefer the
 	 * flavor listed first.  However, some servers list
-	 * AUTH_NULL first.  Our caller plants AUTH_SYS, the
-	 * preferred default, in args->auth_flavors[0] if user
-	 * didn't specify sec= mount option.
+	 * AUTH_NULL first.  Avoid ever choosing AUTH_NULL.
 	 */
-	for (i = 0; i < args->auth_flavor_len; i++)
-		for (j = 0; j < server_authlist_len; j++)
-			if (args->auth_flavors[i] == request->auth_flavs[j]) {
-				dfprintk(MOUNT, "NFS: using auth flavor %d\n",
-					request->auth_flavs[j]);
-				args->auth_flavors[0] = request->auth_flavs[j];
-				return 0;
-			}
+	for (i = 0; i < count; i++) {
+		struct rpcsec_gss_info info;
+
+		flavor = request->auth_flavs[i];
+		switch (flavor) {
+		case RPC_AUTH_UNIX:
+			goto out_set;
+		case RPC_AUTH_NULL:
+			continue;
+		default:
+			if (rpcauth_get_gssinfo(flavor, &info) == 0)
+				goto out_set;
+		}
+	}
 
-	dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
-	nfs_umount(request);
-	return -EACCES;
+out_default:
+	flavor = RPC_AUTH_UNIX;
+out_set:
+	args->auth_flavors[0] = flavor;
+out:
+	dfprintk(MOUNT, "NFS: using auth flavor %d\n", args->auth_flavors[0]);
 }
 
 /*
@@ -1710,12 +1718,8 @@ static int nfs_request_mount(struct nfs_parsed_mount_data *args,
 		return status;
 	}
 
-	/*
-	 * MNTv1 (NFSv2) does not support auth flavor negotiation.
-	 */
-	if (args->mount_server.version != NFS_MNT3_VERSION)
-		return 0;
-	return nfs_walk_authlist(args, &request);
+	nfs_select_flavor(args, &request);
+	return 0;
 }
 
 struct dentry *nfs_try_mount(int flags, const char *dev_name,

fs/nfsd/nfs4xdr.c

@@ -3138,10 +3138,9 @@ nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_
 
 static __be32
 nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
-			 __be32 nfserr,struct svc_export *exp)
+			 __be32 nfserr, struct svc_export *exp)
 {
-	int i = 0;
-	u32 nflavs;
+	u32 i, nflavs;
 	struct exp_flavor_info *flavs;
 	struct exp_flavor_info def_flavs[2];
 	__be32 *p;
@@ -3172,30 +3171,29 @@ nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
 	WRITE32(nflavs);
 	ADJUST_ARGS();
 	for (i = 0; i < nflavs; i++) {
-		u32 flav = flavs[i].pseudoflavor;
-		struct gss_api_mech *gm = gss_mech_get_by_pseudoflavor(flav);
+		struct rpcsec_gss_info info;
 
-		if (gm) {
+		if (rpcauth_get_gssinfo(flavs[i].pseudoflavor, &info) == 0) {
 			RESERVE_SPACE(4);
 			WRITE32(RPC_AUTH_GSS);
 			ADJUST_ARGS();
-			RESERVE_SPACE(4 + gm->gm_oid.len);
-			WRITE32(gm->gm_oid.len);
-			WRITEMEM(gm->gm_oid.data, gm->gm_oid.len);
+			RESERVE_SPACE(4 + info.oid.len);
+			WRITE32(info.oid.len);
+			WRITEMEM(info.oid.data, info.oid.len);
 			ADJUST_ARGS();
 			RESERVE_SPACE(4);
-			WRITE32(0); /* qop */
+			WRITE32(info.qop);
 			ADJUST_ARGS();
 			RESERVE_SPACE(4);
-			WRITE32(gss_pseudoflavor_to_service(gm, flav));
+			WRITE32(info.service);
 			ADJUST_ARGS();
-			gss_mech_put(gm);
 		} else {
 			RESERVE_SPACE(4);
-			WRITE32(flav);
+			WRITE32(flavs[i].pseudoflavor);
 			ADJUST_ARGS();
 		}
 	}
+
 out:
 	if (exp)
 		exp_put(exp);

include/linux/nfs_xdr.h

@@ -14,9 +14,6 @@
 #define NFS_DEF_FILE_IO_SIZE	(4096U)
 #define NFS_MIN_FILE_IO_SIZE	(1024U)
 
-/* Forward declaration for NFS v3 */
-struct nfs4_secinfo_flavors;
-
 struct nfs4_string {
 	unsigned int len;
 	char *data;
@@ -1053,25 +1050,14 @@ struct nfs4_fs_locations_res {
 	struct nfs4_fs_locations       *fs_locations;
 };
 
-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_secinfo4 {
+	u32			flavor;
+	struct rpcsec_gss_info	flavor_info;
 };
 
 struct nfs4_secinfo_flavors {
-	unsigned int num_flavors;
-	struct nfs4_secinfo_flavor flavors[0];
+	unsigned int		num_flavors;
+	struct nfs4_secinfo4	flavors[0];
 };
 
 struct nfs4_secinfo_arg {

include/linux/sunrpc/auth.h

@@ -22,6 +22,8 @@
 /* size of the nodename buffer */
 #define UNX_MAXNODENAME	32
 
+struct rpcsec_gss_info;
+
 /* Work around the lack of a VFS credential */
 struct auth_cred {
 	kuid_t	uid;
@@ -103,6 +105,9 @@ struct rpc_authops {
 	int			(*pipes_create)(struct rpc_auth *);
 	void			(*pipes_destroy)(struct rpc_auth *);
 	int			(*list_pseudoflavors)(rpc_authflavor_t *, int);
+	rpc_authflavor_t	(*info2flavor)(struct rpcsec_gss_info *);
+	int			(*flavor2info)(rpc_authflavor_t,
+						struct rpcsec_gss_info *);
 };
 
 struct rpc_credops {
@@ -137,6 +142,10 @@ int			rpcauth_register(const struct rpc_authops *);
 int			rpcauth_unregister(const struct rpc_authops *);
 struct rpc_auth *	rpcauth_create(rpc_authflavor_t, struct rpc_clnt *);
 void			rpcauth_release(struct rpc_auth *);
+rpc_authflavor_t	rpcauth_get_pseudoflavor(rpc_authflavor_t,
+				struct rpcsec_gss_info *);
+int			rpcauth_get_gssinfo(rpc_authflavor_t,
+				struct rpcsec_gss_info *);
 int			rpcauth_list_flavors(rpc_authflavor_t *, int);
 struct rpc_cred *	rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int);
 void			rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);

include/linux/sunrpc/gss_api.h

@@ -25,10 +25,21 @@ struct gss_ctx {
 
 #define GSS_C_NO_BUFFER		((struct xdr_netobj) 0)
 #define GSS_C_NO_CONTEXT	((struct gss_ctx *) 0)
-#define GSS_C_NULL_OID		((struct xdr_netobj) 0)
+#define GSS_C_QOP_DEFAULT	(0)
 
 /*XXX  arbitrary length - is this set somewhere? */
 #define GSS_OID_MAX_LEN 32
+struct rpcsec_gss_oid {
+	unsigned int	len;
+	u8		data[GSS_OID_MAX_LEN];
+};
+
+/* From RFC 3530 */
+struct rpcsec_gss_info {
+	struct rpcsec_gss_oid	oid;
+	u32			qop;
+	u32			service;
+};
 
 /* gss-api prototypes; note that these are somewhat simplified versions of
  * the prototypes specified in RFC 2744. */
@@ -58,12 +69,14 @@ u32 gss_unwrap(
 u32 gss_delete_sec_context(
 		struct gss_ctx		**ctx_id);
 
-u32 gss_svc_to_pseudoflavor(struct gss_api_mech *, u32 service);
+rpc_authflavor_t gss_svc_to_pseudoflavor(struct gss_api_mech *, u32 qop,
+					u32 service);
 u32 gss_pseudoflavor_to_service(struct gss_api_mech *, u32 pseudoflavor);
 char *gss_service_to_auth_domain_name(struct gss_api_mech *, u32 service);
 
 struct pf_desc {
 	u32	pseudoflavor;
+	u32	qop;
 	u32	service;
 	char	*name;
 	char	*auth_domain_name;
@@ -76,7 +89,7 @@ struct pf_desc {
 struct gss_api_mech {
 	struct list_head	gm_list;
 	struct module		*gm_owner;
-	struct xdr_netobj	gm_oid;
+	struct rpcsec_gss_oid	gm_oid;
 	char			*gm_name;
 	const struct gss_api_ops *gm_ops;
 	/* pseudoflavors supported by this mechanism: */
@@ -117,9 +130,11 @@ struct gss_api_ops {
 int gss_mech_register(struct gss_api_mech *);
 void gss_mech_unregister(struct gss_api_mech *);
 
-/* returns a mechanism descriptor given an OID, and increments the mechanism's
- * reference count. */
-struct gss_api_mech * gss_mech_get_by_OID(struct xdr_netobj *);
+/* Given a GSS security tuple, look up a pseudoflavor */
+rpc_authflavor_t gss_mech_info2flavor(struct rpcsec_gss_info *);
+
+/* Given a pseudoflavor, look up a GSS security tuple */
+int gss_mech_flavor2info(rpc_authflavor_t, struct rpcsec_gss_info *);
 
 /* Returns a reference to a mechanism, given a name like "krb5" etc. */
 struct gss_api_mech *gss_mech_get_by_name(const char *);
@@ -130,9 +145,6 @@ struct gss_api_mech *gss_mech_get_by_pseudoflavor(u32);
 /* Fill in an array with a list of supported pseudoflavors */
 int gss_mech_list_pseudoflavors(rpc_authflavor_t *, int);
 
-/* Just increments the mechanism's reference count and returns its input: */
-struct gss_api_mech * gss_mech_get(struct gss_api_mech *);
-
 /* For every successful gss_mech_get or gss_mech_get_by_* call there must be a
  * corresponding call to gss_mech_put. */
 void gss_mech_put(struct gss_api_mech *);

net/sunrpc/Kconfig

@@ -3,6 +3,7 @@ config SUNRPC
 
 config SUNRPC_GSS
 	tristate
+	select OID_REGISTRY
 
 config SUNRPC_BACKCHANNEL
 	bool

net/sunrpc/auth.c

@@ -82,7 +82,7 @@ MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size");
 
 static u32
 pseudoflavor_to_flavor(u32 flavor) {
-	if (flavor >= RPC_AUTH_MAXFLAVOR)
+	if (flavor > RPC_AUTH_MAXFLAVOR)
 		return RPC_AUTH_GSS;
 	return flavor;
 }
@@ -123,6 +123,79 @@ rpcauth_unregister(const struct rpc_authops *ops)
 }
 EXPORT_SYMBOL_GPL(rpcauth_unregister);
 
+/**
+ * rpcauth_get_pseudoflavor - check if security flavor is supported
+ * @flavor: a security flavor
+ * @info: a GSS mech OID, quality of protection, and service value
+ *
+ * Verifies that an appropriate kernel module is available or already loaded.
+ * Returns an equivalent pseudoflavor, or RPC_AUTH_MAXFLAVOR if "flavor" is
+ * not supported locally.
+ */
+rpc_authflavor_t
+rpcauth_get_pseudoflavor(rpc_authflavor_t flavor, struct rpcsec_gss_info *info)
+{
+	const struct rpc_authops *ops;
+	rpc_authflavor_t pseudoflavor;
+
+	ops = auth_flavors[flavor];
+	if (ops == NULL)
+		request_module("rpc-auth-%u", flavor);
+	spin_lock(&rpc_authflavor_lock);
+	ops = auth_flavors[flavor];
+	if (ops == NULL || !try_module_get(ops->owner)) {
+		spin_unlock(&rpc_authflavor_lock);
+		return RPC_AUTH_MAXFLAVOR;
+	}
+	spin_unlock(&rpc_authflavor_lock);
+
+	pseudoflavor = flavor;
+	if (ops->info2flavor != NULL)
+		pseudoflavor = ops->info2flavor(info);
+
+	module_put(ops->owner);
+	return pseudoflavor;
+}
+EXPORT_SYMBOL_GPL(rpcauth_get_pseudoflavor);
+
+/**
+ * rpcauth_get_gssinfo - find GSS tuple matching a GSS pseudoflavor
+ * @pseudoflavor: GSS pseudoflavor to match
+ * @info: rpcsec_gss_info structure to fill in
+ *
+ * Returns zero and fills in "info" if pseudoflavor matches a
+ * supported mechanism.
+ */
+int
+rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info)
+{
+	rpc_authflavor_t flavor = pseudoflavor_to_flavor(pseudoflavor);
+	const struct rpc_authops *ops;
+	int result;
+
+	if (flavor >= RPC_AUTH_MAXFLAVOR)
+		return -EINVAL;
+
+	ops = auth_flavors[flavor];
+	if (ops == NULL)
+		request_module("rpc-auth-%u", flavor);
+	spin_lock(&rpc_authflavor_lock);
+	ops = auth_flavors[flavor];
+	if (ops == NULL || !try_module_get(ops->owner)) {
+		spin_unlock(&rpc_authflavor_lock);
+		return -ENOENT;
+	}
+	spin_unlock(&rpc_authflavor_lock);
+
+	result = -ENOENT;
+	if (ops->flavor2info != NULL)
+		result = ops->flavor2info(pseudoflavor, info);
+
+	module_put(ops->owner);
+	return result;
+}
+EXPORT_SYMBOL_GPL(rpcauth_get_gssinfo);
+
 /**
  * rpcauth_list_flavors - discover registered flavors and pseudoflavors
  * @array: array to fill in

net/sunrpc/auth_gss/auth_gss.c

@@ -1641,6 +1641,8 @@ static const struct rpc_authops authgss_ops = {
 	.pipes_create	= gss_pipes_dentries_create,
 	.pipes_destroy	= gss_pipes_dentries_destroy,
 	.list_pseudoflavors = gss_mech_list_pseudoflavors,
+	.info2flavor	= gss_mech_info2flavor,
+	.flavor2info	= gss_mech_flavor2info,
 };
 
 static const struct rpc_credops gss_credops = {
@@ -1733,6 +1735,7 @@ static void __exit exit_rpcsec_gss(void)
 	rcu_barrier(); /* Wait for completion of call_rcu()'s */
 }
 
+MODULE_ALIAS("rpc-auth-6");
 MODULE_LICENSE("GPL");
 module_param_named(expired_cred_retry_delay,
 		   gss_expired_cred_retry_delay,

net/sunrpc/auth_gss/gss_krb5_mech.c

@@ -729,16 +729,19 @@ static const struct gss_api_ops gss_kerberos_ops = {
 static struct pf_desc gss_kerberos_pfs[] = {
 	[0] = {
 		.pseudoflavor = RPC_AUTH_GSS_KRB5,
+		.qop = GSS_C_QOP_DEFAULT,
 		.service = RPC_GSS_SVC_NONE,
 		.name = "krb5",
 	},
 	[1] = {
 		.pseudoflavor = RPC_AUTH_GSS_KRB5I,
+		.qop = GSS_C_QOP_DEFAULT,
 		.service = RPC_GSS_SVC_INTEGRITY,
 		.name = "krb5i",
 	},
 	[2] = {
 		.pseudoflavor = RPC_AUTH_GSS_KRB5P,
+		.qop = GSS_C_QOP_DEFAULT,
 		.service = RPC_GSS_SVC_PRIVACY,
 		.name = "krb5p",
 	},
@@ -750,11 +753,12 @@ MODULE_ALIAS("rpc-auth-gss-krb5p");
 MODULE_ALIAS("rpc-auth-gss-390003");
 MODULE_ALIAS("rpc-auth-gss-390004");
 MODULE_ALIAS("rpc-auth-gss-390005");
+MODULE_ALIAS("rpc-auth-gss-1.2.840.113554.1.2.2");
 
 static struct gss_api_mech gss_kerberos_mech = {
 	.gm_name	= "krb5",
 	.gm_owner	= THIS_MODULE,
-	.gm_oid		= {9, (void *)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"},
+	.gm_oid		= { 9, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02" },
 	.gm_ops		= &gss_kerberos_ops,
 	.gm_pf_num	= ARRAY_SIZE(gss_kerberos_pfs),
 	.gm_pfs		= gss_kerberos_pfs,

net/sunrpc/auth_gss/gss_mech_switch.c

@@ -36,6 +36,7 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/oid_registry.h>
 #include <linux/sunrpc/msg_prot.h>
 #include <linux/sunrpc/gss_asn1.h>
 #include <linux/sunrpc/auth_gss.h>
@@ -102,8 +103,13 @@ gss_mech_svc_setup(struct gss_api_mech *gm)
 	return status;
 }
 
-int
-gss_mech_register(struct gss_api_mech *gm)
+/**
+ * gss_mech_register - register a GSS mechanism
+ * @gm: GSS mechanism handle
+ *
+ * Returns zero if successful, or a negative errno.
+ */
+int gss_mech_register(struct gss_api_mech *gm)
 {
 	int status;
 
@@ -116,11 +122,14 @@ gss_mech_register(struct gss_api_mech *gm)
 	dprintk("RPC:       registered gss mechanism %s\n", gm->gm_name);
 	return 0;
 }
-
 EXPORT_SYMBOL_GPL(gss_mech_register);
 
-void
-gss_mech_unregister(struct gss_api_mech *gm)
+/**
+ * gss_mech_unregister - release a GSS mechanism
+ * @gm: GSS mechanism handle
+ *
+ */
+void gss_mech_unregister(struct gss_api_mech *gm)
 {
 	spin_lock(&registered_mechs_lock);
 	list_del(&gm->gm_list);
@@ -128,18 +137,14 @@ gss_mech_unregister(struct gss_api_mech *gm)
 	dprintk("RPC:       unregistered gss mechanism %s\n", gm->gm_name);
 	gss_mech_free(gm);
 }
-
 EXPORT_SYMBOL_GPL(gss_mech_unregister);
 
-struct gss_api_mech *
-gss_mech_get(struct gss_api_mech *gm)
+static struct gss_api_mech *gss_mech_get(struct gss_api_mech *gm)
 {
 	__module_get(gm->gm_owner);
 	return gm;
 }
 
-EXPORT_SYMBOL_GPL(gss_mech_get);
-
 static struct gss_api_mech *
 _gss_mech_get_by_name(const char *name)
 {
@@ -169,12 +174,16 @@ struct gss_api_mech * gss_mech_get_by_name(const char *name)
 	}
 	return gm;
 }
-EXPORT_SYMBOL_GPL(gss_mech_get_by_name);
 
-struct gss_api_mech *
-gss_mech_get_by_OID(struct xdr_netobj *obj)
+static struct gss_api_mech *gss_mech_get_by_OID(struct rpcsec_gss_oid *obj)
 {
 	struct gss_api_mech	*pos, *gm = NULL;
+	char buf[32];
+
+	if (sprint_oid(obj->data, obj->len, buf, sizeof(buf)) < 0)
+		return NULL;
+	dprintk("RPC:       %s(%s)\n", __func__, buf);
+	request_module("rpc-auth-gss-%s", buf);
 
 	spin_lock(&registered_mechs_lock);
 	list_for_each_entry(pos, &registered_mechs, gm_list) {
@@ -188,11 +197,8 @@ gss_mech_get_by_OID(struct xdr_netobj *obj)
 	}
 	spin_unlock(&registered_mechs_lock);
 	return gm;
-
 }
 
-EXPORT_SYMBOL_GPL(gss_mech_get_by_OID);
-
 static inline int
 mech_supports_pseudoflavor(struct gss_api_mech *gm, u32 pseudoflavor)
 {
@@ -237,8 +243,6 @@ gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
 	return gm;
 }
 
-EXPORT_SYMBOL_GPL(gss_mech_get_by_pseudoflavor);
-
 /**
  * gss_mech_list_pseudoflavors - Discover registered GSS pseudoflavors
  * @array: array to fill in
@@ -268,19 +272,82 @@ int gss_mech_list_pseudoflavors(rpc_authflavor_t *array_ptr, int size)
 	return i;
 }
 
-u32
-gss_svc_to_pseudoflavor(struct gss_api_mech *gm, u32 service)
+/**
+ * gss_svc_to_pseudoflavor - map a GSS service number to a pseudoflavor
+ * @gm: GSS mechanism handle
+ * @qop: GSS quality-of-protection value
+ * @service: GSS service value
+ *
+ * Returns a matching security flavor, or RPC_AUTH_MAXFLAVOR if none is found.
+ */
+rpc_authflavor_t gss_svc_to_pseudoflavor(struct gss_api_mech *gm, u32 qop,
+					 u32 service)
 {
 	int i;
 
 	for (i = 0; i < gm->gm_pf_num; i++) {
-		if (gm->gm_pfs[i].service == service) {
+		if (gm->gm_pfs[i].qop == qop &&
+		    gm->gm_pfs[i].service == service) {
 			return gm->gm_pfs[i].pseudoflavor;
 		}
 	}
-	return RPC_AUTH_MAXFLAVOR; /* illegal value */
+	return RPC_AUTH_MAXFLAVOR;
+}
+
+/**
+ * gss_mech_info2flavor - look up a pseudoflavor given a GSS tuple
+ * @info: a GSS mech OID, quality of protection, and service value
+ *
+ * Returns a matching pseudoflavor, or RPC_AUTH_MAXFLAVOR if the tuple is
+ * not supported.
+ */
+rpc_authflavor_t gss_mech_info2flavor(struct rpcsec_gss_info *info)
+{
+	rpc_authflavor_t pseudoflavor;
+	struct gss_api_mech *gm;
+
+	gm = gss_mech_get_by_OID(&info->oid);
+	if (gm == NULL)
+		return RPC_AUTH_MAXFLAVOR;
+
+	pseudoflavor = gss_svc_to_pseudoflavor(gm, info->qop, info->service);
+
+	gss_mech_put(gm);
+	return pseudoflavor;
+}
+
+/**
+ * gss_mech_flavor2info - look up a GSS tuple for a given pseudoflavor
+ * @pseudoflavor: GSS pseudoflavor to match
+ * @info: rpcsec_gss_info structure to fill in
+ *
+ * Returns zero and fills in "info" if pseudoflavor matches a
+ * supported mechanism.  Otherwise a negative errno is returned.
+ */
+int gss_mech_flavor2info(rpc_authflavor_t pseudoflavor,
+			 struct rpcsec_gss_info *info)
+{
+	struct gss_api_mech *gm;
+	int i;
+
+	gm = gss_mech_get_by_pseudoflavor(pseudoflavor);
+	if (gm == NULL)
+		return -ENOENT;
+
+	for (i = 0; i < gm->gm_pf_num; i++) {
+		if (gm->gm_pfs[i].pseudoflavor == pseudoflavor) {
+			memcpy(info->oid.data, gm->gm_oid.data, gm->gm_oid.len);
+			info->oid.len = gm->gm_oid.len;
+			info->qop = gm->gm_pfs[i].qop;
+			info->service = gm->gm_pfs[i].service;
+			gss_mech_put(gm);
+			return 0;
+		}
+	}
+
+	gss_mech_put(gm);
+	return -ENOENT;
 }
-EXPORT_SYMBOL_GPL(gss_svc_to_pseudoflavor);
 
 u32
 gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
@@ -294,8 +361,6 @@ gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
 	return 0;
 }
 
-EXPORT_SYMBOL_GPL(gss_pseudoflavor_to_service);
-
 char *
 gss_service_to_auth_domain_name(struct gss_api_mech *gm, u32 service)
 {
@@ -308,8 +373,6 @@ gss_service_to_auth_domain_name(struct gss_api_mech *gm, u32 service)
 	return NULL;
 }
 
-EXPORT_SYMBOL_GPL(gss_service_to_auth_domain_name);
-
 void
 gss_mech_put(struct gss_api_mech * gm)
 {
@@ -317,8 +380,6 @@ gss_mech_put(struct gss_api_mech * gm)
 		module_put(gm->gm_owner);
 }
 
-EXPORT_SYMBOL_GPL(gss_mech_put);
-
 /* The mech could probably be determined from the token instead, but it's just
  * as easy for now to pass it in. */
 int

net/sunrpc/auth_gss/svcauth_gss.c

@@ -1216,7 +1216,9 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
 		svcdata->rsci = rsci;
 		cache_get(&rsci->h);
 		rqstp->rq_cred.cr_flavor = gss_svc_to_pseudoflavor(
-					rsci->mechctx->mech_type, gc->gc_svc);
+					rsci->mechctx->mech_type,
+					GSS_C_QOP_DEFAULT,
+					gc->gc_svc);
 		ret = SVC_OK;
 		goto out;
 	}