SUNRPC: Refactor nfsd4_do_encode_secinfo()

Clean up.  This matches a similar API for the client side, and
keeps ULP fingers out the of the GSS mech switch.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 69 insertions, 2 deletions

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 9b81be8d9946..2bc0cc2196e0 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -159,6 +159,41 @@ rpcauth_get_pseudoflavor(rpc_authflavor_t flavor, struct rpcsec_gss_info *info)
 EXPORT_SYMBOL_GPL(rpcauth_get_pseudoflavor);
 
 /**
+ * rpcauth_get_gssinfo - find GSS tuple matching a GSS pseudoflavor
+ * @pseudoflavor: GSS pseudoflavor to match
+ * @info: rpcsec_gss_info structure to fill in
+ *
+ * Returns zero and fills in "info" if pseudoflavor matches a
+ * supported mechanism.
+ */
+int
+rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info)
+{
+        rpc_authflavor_t flavor = pseudoflavor_to_flavor(pseudoflavor);
+        const struct rpc_authops *ops;
+        int result;
+
+        ops = auth_flavors[flavor];
+        if (ops == NULL)
+                request_module("rpc-auth-%u", flavor);
+        spin_lock(&rpc_authflavor_lock);
+        ops = auth_flavors[flavor];
+        if (ops == NULL || !try_module_get(ops->owner)) {
+                spin_unlock(&rpc_authflavor_lock);
+                return -ENOENT;
+        }
+        spin_unlock(&rpc_authflavor_lock);
+
+        result = -ENOENT;
+        if (ops->flavor2info != NULL)
+                result = ops->flavor2info(pseudoflavor, info);
+
+        module_put(ops->owner);
+        return result;
+}
+EXPORT_SYMBOL_GPL(rpcauth_get_gssinfo);
+
+/**
  * rpcauth_list_flavors - discover registered flavors and pseudoflavors
  * @array: array to fill in
  * @size: size of "array"
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index a7420076ef39..51415b07174e 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -1642,6 +1642,7 @@ static const struct rpc_authops authgss_ops = {
         .pipes_destroy  = gss_pipes_dentries_destroy,
         .list_pseudoflavors = gss_mech_list_pseudoflavors,
         .info2flavor    = gss_mech_info2flavor,
+        .flavor2info    = gss_mech_flavor2info,
 };
 
 static const struct rpc_credops gss_credops = {
diff --git a/net/sunrpc/auth_gss/gss_mech_switch.c b/net/sunrpc/auth_gss/gss_mech_switch.c
index 81fb6f3e2424..deaa7ae81cdf 100644
--- a/net/sunrpc/auth_gss/gss_mech_switch.c
+++ b/net/sunrpc/auth_gss/gss_mech_switch.c
@@ -240,8 +240,6 @@ gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
         return gm;
 }
 
-EXPORT_SYMBOL_GPL(gss_mech_get_by_pseudoflavor);
-
 /**
  * gss_mech_list_pseudoflavors - Discover registered GSS pseudoflavors
  * @array: array to fill in
@@ -315,6 +313,39 @@ rpc_authflavor_t gss_mech_info2flavor(struct rpcsec_gss_info *info)
         return pseudoflavor;
 }
 
+/**
+ * gss_mech_flavor2info - look up a GSS tuple for a given pseudoflavor
+ * @pseudoflavor: GSS pseudoflavor to match
+ * @info: rpcsec_gss_info structure to fill in
+ *
+ * Returns zero and fills in "info" if pseudoflavor matches a
+ * supported mechanism.  Otherwise a negative errno is returned.
+ */
+int gss_mech_flavor2info(rpc_authflavor_t pseudoflavor,
+                         struct rpcsec_gss_info *info)
+{
+        struct gss_api_mech *gm;
+        int i;
+
+        gm = gss_mech_get_by_pseudoflavor(pseudoflavor);
+        if (gm == NULL)
+                return -ENOENT;
+
+        for (i = 0; i < gm->gm_pf_num; i++) {
+                if (gm->gm_pfs[i].pseudoflavor == pseudoflavor) {
+                        memcpy(info->oid.data, gm->gm_oid.data, gm->gm_oid.len);
+                        info->oid.len = gm->gm_oid.len;
+                        info->qop = gm->gm_pfs[i].qop;
+                        info->service = gm->gm_pfs[i].service;
+                        gss_mech_put(gm);
+                        return 0;
+                }
+        }
+
+        gss_mech_put(gm);
+        return -ENOENT;
+}
+
 u32
 gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
 {