knfsd: nfsd: set rq_client to ip-address-determined-domain

We want it to be possible for users to restrict exports both by IP address and
by pseudoflavor.  The pseudoflavor information has previously been passed
using special auth_domains stored in the rq_client field.  After the preceding
patch that stored the pseudoflavor in rq_pflavor, that's now superfluous; so
now we use rq_client for the ip information, as auth_null and auth_unix do.

However, we keep around the special auth_domain in the rq_gssclient field for
backwards compatibility purposes, so we can still do upcalls using the old
"gss/pseudoflavor" auth_domain if upcalls using the unix domain to give us an
appropriate export.  This allows us to continue supporting old mountd.

In fact, for this first patch, we always use the "gss/pseudoflavor"
auth_domain (and only it) if it is available; thus rq_client is ignored in the
auth_gss case, and this patch on its own makes no change in behavior; that
will be left to later patches.

Note on idmap: I'm almost tempted to just replace the auth_domain in the idmap
upcall by a dummy value--no version of idmapd has ever used it, and it's
unlikely anyone really wants to perform idmapping differently depending on the
where the client is (they may want to perform *credential* mapping
differently, but that's a different matter--the idmapper just handles id's
used in getattr and setattr).  But I'm updating the idmapd code anyway, just
out of general backwards-compatibility paranoia.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 21 insertions, 4 deletions

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 7a3e1758bea..e4b3de08b04 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -913,10 +913,23 @@ svcauth_gss_set_client(struct svc_rqst *rqstp)
 	struct gss_svc_data *svcdata = rqstp->rq_auth_data;
 	struct rsc *rsci = svcdata->rsci;
 	struct rpc_gss_wire_cred *gc = &svcdata->clcred;
+	int stat;
 
-	rqstp->rq_client = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
-	if (rqstp->rq_client == NULL)
+	/*
+	 * A gss export can be specified either by:
+	 * 	export	*(sec=krb5,rw)
+	 * or by
+	 * 	export gss/krb5(rw)
+	 * The latter is deprecated; but for backwards compatibility reasons
+	 * the nfsd code will still fall back on trying it if the former
+	 * doesn't work; so we try to make both available to nfsd, below.
+	 */
+	rqstp->rq_gssclient = find_gss_auth_domain(rsci->mechctx, gc->gc_svc);
+	if (rqstp->rq_gssclient == NULL)
 		return SVC_DENIED;
+	stat = svcauth_unix_set_client(rqstp);
+	if (stat == SVC_DROP)
+		return stat;
 	return SVC_OK;
 }
 
@@ -1088,7 +1101,6 @@ svcauth_gss_accept(struct svc_rqst *rqstp, __be32 *authp)
 			svc_putnl(resv, GSS_SEQ_WIN);
 			if (svc_safe_putnetobj(resv, &rsip->out_token))
 				goto drop;
-			rqstp->rq_client = NULL;
 		}
 		goto complete;
 	case RPC_GSS_PROC_DESTROY:
@@ -1319,6 +1331,9 @@ out_err:
 	if (rqstp->rq_client)
 		auth_domain_put(rqstp->rq_client);
 	rqstp->rq_client = NULL;
+	if (rqstp->rq_gssclient)
+		auth_domain_put(rqstp->rq_gssclient);
+	rqstp->rq_gssclient = NULL;
 	if (rqstp->rq_cred.cr_group_info)
 		put_group_info(rqstp->rq_cred.cr_group_info);
 	rqstp->rq_cred.cr_group_info = NULL;
diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index d9fdf2e4d24..411479411b2 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -638,7 +638,7 @@ static int unix_gid_find(uid_t uid, struct group_info **gip,
 	}
 }
 
-static int
+int
 svcauth_unix_set_client(struct svc_rqst *rqstp)
 {
 	struct sockaddr_in *sin = svc_addr_in(rqstp);
@@ -673,6 +673,8 @@ svcauth_unix_set_client(struct svc_rqst *rqstp)
 	return SVC_OK;
 }
 
+EXPORT_SYMBOL(svcauth_unix_set_client);
+
 static int
 svcauth_null_accept(struct svc_rqst *rqstp, __be32 *authp)
 {