gss_krb5: Add upcall info indicating supported kerberos enctypes
The text based upcall now indicates which Kerberos encryption types are
supported by the kernel rpcsecgss code. This is used by gssd to
determine which encryption types it should attempt to negotiate
when creating a context with a server.
The server principal's database and keytab encryption types are
what limits what it should negotiate. Therefore, its keytab
should be created with only the enctypes listed by this file.
Currently we support des-cbc-crc, des-cbc-md4 and des-cbc-md5
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/sunrpc/gss_api.h b/include/linux/sunrpc/gss_api.h
index 03f3333..b22d7f1 100644
--- a/include/linux/sunrpc/gss_api.h
+++ b/include/linux/sunrpc/gss_api.h
@@ -80,6 +80,8 @@
/* pseudoflavors supported by this mechanism: */
int gm_pf_num;
struct pf_desc * gm_pfs;
+ /* Should the following be a callback operation instead? */
+ const char *gm_upcall_enctypes;
};
/* and must provide the following operations: */
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index d64a58b..6654c85 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -377,11 +377,12 @@
static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
struct rpc_clnt *clnt, int machine_cred)
{
+ struct gss_api_mech *mech = gss_msg->auth->mech;
char *p = gss_msg->databuf;
int len = 0;
gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ",
- gss_msg->auth->mech->gm_name,
+ mech->gm_name,
gss_msg->uid);
p += gss_msg->msg.len;
if (clnt->cl_principal) {
@@ -398,6 +399,11 @@
p += len;
gss_msg->msg.len += len;
}
+ if (mech->gm_upcall_enctypes) {
+ len = sprintf(p, mech->gm_upcall_enctypes);
+ p += len;
+ gss_msg->msg.len += len;
+ }
len = sprintf(p, "\n");
gss_msg->msg.len += len;
diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c
index 8b612e7..03f1dcd 100644
--- a/net/sunrpc/auth_gss/gss_krb5_mech.c
+++ b/net/sunrpc/auth_gss/gss_krb5_mech.c
@@ -552,6 +552,7 @@
.gm_ops = &gss_kerberos_ops,
.gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs),
.gm_pfs = gss_kerberos_pfs,
+ .gm_upcall_enctypes = "enctypes=3,1,2 ",
};
static int __init init_kerberos_module(void)
