+/*
+ * Validate NFSv4 mount options
+ */
+static int nfs4_validate_mount_data(struct nfs4_mount_data **options,
+ const char *dev_name,
+ struct sockaddr_in *addr,
+ rpc_authflavor_t *authflavour,
+ char **hostname,
+ char **mntpath,
+ char **ip_addr)
+{
+ struct nfs4_mount_data *data = *options;
+ char *c;
+
+ if (data == NULL)
+ goto out_no_data;
+
+ switch (data->version) {
+ case 1:
+ if (data->host_addrlen != sizeof(*addr))
+ goto out_no_address;
+ if (copy_from_user(addr, data->host_addr, sizeof(*addr)))
+ return -EFAULT;
+ if (addr->sin_port == 0)
+ addr->sin_port = htons(NFS_PORT);
+ if (!nfs_verify_server_address((struct sockaddr *) addr))
+ goto out_no_address;
+
+ switch (data->auth_flavourlen) {
+ case 0:
+ *authflavour = RPC_AUTH_UNIX;
+ break;
+ case 1:
+ if (copy_from_user(authflavour, data->auth_flavours,
+ sizeof(*authflavour)))
+ return -EFAULT;
+ break;
+ default:
+ goto out_inval_auth;
+ }
+
+ c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
+ if (IS_ERR(c))
+ return PTR_ERR(c);
+ *hostname = c;
+
+ c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
+ if (IS_ERR(c))
+ return PTR_ERR(c);
+ *mntpath = c;
+ dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *mntpath);
+
+ c = strndup_user(data->client_addr.data, 16);
+ if (IS_ERR(c))
+ return PTR_ERR(c);
+ *ip_addr = c;
+
+ break;
+ default:
+ goto out_bad_version;
+ }
+
+ return 0;
+
+out_no_data:
+ dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
+ return -EINVAL;
+
+out_inval_auth:
+ dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
+ data->auth_flavourlen);
+ return -EINVAL;
+
+out_no_address:
+ dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
+ return -EINVAL;
+
+out_bad_version:
+ dfprintk(MOUNT, "NFS4: bad nfs_mount_data version %d\n",
+ data->version);
+ return -EINVAL;
+}
+