nfsd: add proc file listing kernel's gss_krb5 enctypes
Add a new proc file which lists the encryption types supported
by the kernel's gss_krb5 code.
Newer MIT Kerberos libraries support the assertion of acceptor
subkeys. This enctype information allows user-land (svcgssd)
to request that the Kerberos libraries limit the encryption
types that it uses when generating the subkeys.
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 33b3e2b..35dcfa8 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -12,13 +12,14 @@
#include <linux/nfsd/syscall.h>
#include <linux/lockd/lockd.h>
#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/gss_api.h>
#include "idmap.h"
#include "nfsd.h"
#include "cache.h"
/*
- * We have a single directory with 9 nodes in it.
+ * We have a single directory with several nodes in it.
*/
enum {
NFSD_Root = 1,
@@ -42,6 +43,7 @@
NFSD_Versions,
NFSD_Ports,
NFSD_MaxBlkSize,
+ NFSD_SupportedEnctypes,
/*
* The below MUST come last. Otherwise we leave a hole in nfsd_files[]
* with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
@@ -187,6 +189,32 @@
.release = single_release,
};
+static int supported_enctypes_show(struct seq_file *m, void *v)
+{
+ struct gss_api_mech *k5mech;
+
+ k5mech = gss_mech_get_by_name("krb5");
+ if (k5mech == NULL)
+ goto out;
+ if (k5mech->gm_upcall_enctypes != NULL)
+ seq_printf(m, k5mech->gm_upcall_enctypes);
+ gss_mech_put(k5mech);
+out:
+ return 0;
+}
+
+static int supported_enctypes_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, supported_enctypes_show, NULL);
+}
+
+static struct file_operations supported_enctypes_ops = {
+ .open = supported_enctypes_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
extern int nfsd_pool_stats_open(struct inode *inode, struct file *file);
extern int nfsd_pool_stats_release(struct inode *inode, struct file *file);
@@ -1397,6 +1425,7 @@
[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},
[NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO},
+ [NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", &supported_enctypes_ops, S_IRUGO},
#ifdef CONFIG_NFSD_V4
[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Gracetime] = {"nfsv4gracetime", &transaction_ops, S_IWUSR|S_IRUSR},