nfsd4: fix gss-proxy 4.1 mounts for some AD principals
The principal name on a gss cred is used to setup the NFSv4.0 callback,
which has to have a client principal name to authenticate to.
That code wants the name to be in the form servicetype@hostname.
rpc.svcgssd passes down such names (and passes down no principal name at
all in the case the principal isn't a service principal).
gss-proxy always passes down the principal name, and passes it down in
the form servicetype/hostname@REALM. So we've been munging the name
gss-proxy passes down into the format the NFSv4.0 callback code expects,
or throwing away the name if we can't.
Since the introduction of the MACH_CRED enforcement in NFSv4.1, we've
also been using the principal name to verify that certain operations are
done as the same principal as was used on the original EXCHANGE_ID call.
For that application, the original name passed down by gss-proxy is also
useful.
Lack of that name in some cases was causing some kerberized NFSv4.1
mount failures in an Active Directory environment.
This fix only works in the gss-proxy case. The fix for legacy
rpc.svcgssd would be more involved, and rpc.svcgssd already has other
problems in the AD case.
Reported-and-tested-by: James Ralston <ralston@pobox.com>
Acked-by: Simo Sorce <simo@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index ed58ced..113ecbf 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1875,6 +1875,10 @@
ret = strdup_if_nonnull(&target->cr_principal, source->cr_principal);
if (ret)
return ret;
+ ret = strdup_if_nonnull(&target->cr_raw_principal,
+ source->cr_raw_principal);
+ if (ret)
+ return ret;
target->cr_flavor = source->cr_flavor;
target->cr_uid = source->cr_uid;
target->cr_gid = source->cr_gid;
@@ -1978,6 +1982,9 @@
return false;
if (!svc_rqst_integrity_protected(rqstp))
return false;
+ if (cl->cl_cred.cr_raw_principal)
+ return 0 == strcmp(cl->cl_cred.cr_raw_principal,
+ cr->cr_raw_principal);
if (!cr->cr_principal)
return false;
return 0 == strcmp(cl->cl_cred.cr_principal, cr->cr_principal);
@@ -2390,7 +2397,8 @@
* Which is a bug, really. Anyway, we can't enforce
* MACH_CRED in that case, better to give up now:
*/
- if (!new->cl_cred.cr_principal) {
+ if (!new->cl_cred.cr_principal &&
+ !new->cl_cred.cr_raw_principal) {
status = nfserr_serverfault;
goto out_nolock;
}