Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:34405 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759824Ab2CVUrH (ORCPT ); Thu, 22 Mar 2012 16:47:07 -0400 Date: Thu, 22 Mar 2012 16:47:05 -0400 To: Trond Myklebust Cc: linux-nfs@vger.kernel.org Subject: Re: [PATCH] NFSv4: Change the default setting of the nfs4_disable_idmapping parameter Message-ID: <20120322204705.GA23737@fieldses.org> References: <1326138354-8138-1-git-send-email-Trond.Myklebust@netapp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1326138354-8138-1-git-send-email-Trond.Myklebust@netapp.com> From: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: By the way, I finally got around to looking at the server side. We don't have any way to negotiate with the client--we don't get an error back if the name we return in a getattr reply isn't one the client likes--so I don't think I can default the new behavior to "on" without breaking existing setups. Other than that I think I'll just copy the client, module parameter and all. That allows us to do the numeric case in-kernel and avoid polluting our mapping cache with lots of "obvious" 123<->"123" mappings. (OK, maybe I shouldn't copy the same parameter name, though--even if it works it might be confusing.) (Untested.) --b. diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 0d79a88..aa90574 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1686,6 +1686,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted. The default is to send the implementation identification information. + nfsd.nfs4_disable_idmapping= + [NFSv4] When set to to '1', the NFSv4 server + will return only numeric uids and gids to clients + using auth_sys, and will expect numeric uids and + gids from such clients. This intended to ease + migration from NFSv2/v3. The default is '0' for + backwards-compatibility reasons, but '1' is + recommended for any newly set up server. objlayoutdriver.osd_login_prog= [NFS] [OBJLAYOUT] sets the pathname to the program which diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c index 9409627..4a1e3ce 100644 --- a/fs/nfsd/nfs4idmap.c +++ b/fs/nfsd/nfs4idmap.c @@ -41,6 +41,14 @@ #include "nfsd.h" /* + * Turn off idmapping when using AUTH_SYS. + */ +static bool nfs4_disable_idmapping = false; +module_param(nfs4_disable_idmapping, bool, 0644); +MODULE_PARM_DESC(nfs4_disable_idmapping, + "Turn off server's NFSv4 idmapping when using 'sec=sys'"); + +/* * Cache entry */ @@ -561,28 +569,60 @@ idmap_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name) return ret; } +static __be32 +numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, uid_t *id) +{ + int ret; + char buf[11]; + + if (namelen + 1 > sizeof(buf)) + /* too long to represent a 32-bit id: */ + return nfserr_badowner; + /* Just to make sure it's null-terminated: */ + memcpy(buf, name, namelen); + buf[namelen] = '\0'; + ret = strict_strtoul(name, 10, (unsigned long *)id); + return ret ? nfserr_badowner : 0; +} + +static __be32 +do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, uid_t *id) +{ + if (nfs4_disable_idmapping && rqstp->rq_flavor < RPC_AUTH_GSS) + return numeric_name_to_id(rqstp, type, name, namelen, id); + return idmap_name_to_id(rqstp, type, name, namelen, id); +} + +static int +do_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name) +{ + if (nfs4_disable_idmapping && rqstp->rq_flavor < RPC_AUTH_GSS) + return sprintf(name, "%u", id); + return idmap_id_to_name(rqstp, type, id, name); +} + __be32 nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen, __u32 *id) { - return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id); + return do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id); } __be32 nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen, __u32 *id) { - return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id); + return do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id); } int nfsd_map_uid_to_name(struct svc_rqst *rqstp, __u32 id, char *name) { - return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name); + return do_id_to_name(rqstp, IDMAP_TYPE_USER, id, name); } int nfsd_map_gid_to_name(struct svc_rqst *rqstp, __u32 id, char *name) { - return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name); + return do_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name); }