From 414ca017a54d26c3a58ed1504884e51448d22ae1 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Fri, 20 Nov 2015 10:48:02 -0500 Subject: 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 Acked-by: Simo Sorce Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4state.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'fs/nfsd') diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index ed58ced6fa8b..113ecbfac25c 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -1873,6 +1873,10 @@ static int copy_cred(struct svc_cred *target, struct svc_cred *source) int ret; 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; @@ -1978,6 +1982,9 @@ static bool mach_creds_match(struct nfs4_client *cl, struct svc_rqst *rqstp) 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 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, * 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; } -- cgit v1.2.3