From 108b833cde9c9b93204e6a4e455829a67f9785c3 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 20 Aug 2018 10:39:16 -0400 Subject: [PATCH] sunrpc: Add comment defining gssd upcall API keywords During review, it was found that the target, service, and srchost keywords are easily conflated. Add an explainer. Signed-off-by: Chuck Lever Signed-off-by: J. Bruce Fields --- net/sunrpc/auth_gss/auth_gss.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index 1943e1198804..246075960712 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -461,12 +461,28 @@ static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, buflen -= len; p += len; gss_msg->msg.len = len; + + /* + * target= is a full service principal that names the remote + * identity that we are authenticating to. + */ if (target_name) { len = scnprintf(p, buflen, "target=%s ", target_name); buflen -= len; p += len; gss_msg->msg.len += len; } + + /* + * gssd uses service= and srchost= to select a matching key from + * the system's keytab to use as the source principal. + * + * service= is the service name part of the source principal, + * or "*" (meaning choose any). + * + * srchost= is the hostname part of the source principal. When + * not provided, gssd uses the local hostname. + */ if (service_name) { char *c = strchr(service_name, '@'); @@ -482,6 +498,7 @@ static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg, p += len; gss_msg->msg.len += len; } + if (mech->gm_upcall_enctypes) { len = scnprintf(p, buflen, "enctypes=%s ", mech->gm_upcall_enctypes);