3 files changed, 153 insertions, 2 deletions

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 5071e435471c..415159061cd0 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -343,6 +343,27 @@ out_nocache:
 EXPORT_SYMBOL_GPL(rpcauth_init_credcache);
 
 /*
+ * Setup a credential key lifetime timeout notification
+ */
+int
+rpcauth_key_timeout_notify(struct rpc_auth *auth, struct rpc_cred *cred)
+{
+	if (!cred->cr_auth->au_ops->key_timeout)
+		return 0;
+	return cred->cr_auth->au_ops->key_timeout(auth, cred);
+}
+EXPORT_SYMBOL_GPL(rpcauth_key_timeout_notify);
+
+bool
+rpcauth_cred_key_to_expire(struct rpc_cred *cred)
+{
+	if (!cred->cr_ops->crkey_to_expire)
+		return false;
+	return cred->cr_ops->crkey_to_expire(cred);
+}
+EXPORT_SYMBOL_GPL(rpcauth_cred_key_to_expire);
+
+/*
  * Destroy a list of credentials
  */
 static inline
diff --git a/net/sunrpc/auth_generic.c b/net/sunrpc/auth_generic.c
index b6badafc6494..f6d84be49050 100644
--- a/net/sunrpc/auth_generic.c
+++ b/net/sunrpc/auth_generic.c
@@ -89,6 +89,7 @@ generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 	gcred->acred.uid = acred->uid;
 	gcred->acred.gid = acred->gid;
 	gcred->acred.group_info = acred->group_info;
+	gcred->acred.ac_flags = 0;
 	if (gcred->acred.group_info != NULL)
 		get_group_info(gcred->acred.group_info);
 	gcred->acred.machine_cred = acred->machine_cred;
@@ -182,11 +183,78 @@ void rpc_destroy_generic_auth(void)
 	rpcauth_destroy_credcache(&generic_auth);
 }
 
+/*
+ * Test the the current time (now) against the underlying credential key expiry
+ * minus a timeout and setup notification.
+ *
+ * The normal case:
+ * If 'now' is before the key expiry minus RPC_KEY_EXPIRE_TIMEO, set
+ * the RPC_CRED_NOTIFY_TIMEOUT flag to setup the underlying credential
+ * rpc_credops crmatch routine to notify this generic cred when it's key
+ * expiration is within RPC_KEY_EXPIRE_TIMEO, and return 0.
+ *
+ * The error case:
+ * If the underlying cred lookup fails, return -EACCES.
+ *
+ * The 'almost' error case:
+ * If 'now' is within key expiry minus RPC_KEY_EXPIRE_TIMEO, but not within
+ * key expiry minus RPC_KEY_EXPIRE_FAIL, set the RPC_CRED_EXPIRE_SOON bit
+ * on the acred ac_flags and return 0.
+ */
+static int
+generic_key_timeout(struct rpc_auth *auth, struct rpc_cred *cred)
+{
+	struct auth_cred *acred = &container_of(cred, struct generic_cred,
+						gc_base)->acred;
+	struct rpc_cred *tcred;
+	int ret = 0;
+
+
+	/* Fast track for non crkey_timeout (no key) underlying credentials */
+	if (test_bit(RPC_CRED_NO_CRKEY_TIMEOUT, &acred->ac_flags))
+		return 0;
+
+	/* Fast track for the normal case */
+	if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags))
+		return 0;
+
+	/* lookup_cred either returns a valid referenced rpc_cred, or PTR_ERR */
+	tcred = auth->au_ops->lookup_cred(auth, acred, 0);
+	if (IS_ERR(tcred))
+		return -EACCES;
+
+	if (!tcred->cr_ops->crkey_timeout) {
+		set_bit(RPC_CRED_NO_CRKEY_TIMEOUT, &acred->ac_flags);
+		ret = 0;
+		goto out_put;
+	}
+
+	/* Test for the almost error case */
+	ret = tcred->cr_ops->crkey_timeout(tcred);
+	if (ret != 0) {
+		set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
+		ret = 0;
+	} else {
+		/* In case underlying cred key has been reset */
+		if (test_and_clear_bit(RPC_CRED_KEY_EXPIRE_SOON,
+					&acred->ac_flags))
+			dprintk("RPC:        UID %d Credential key reset\n",
+				tcred->cr_uid);
+		/* set up fasttrack for the normal case */
+		set_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
+	}
+
+out_put:
+	put_rpccred(tcred);
+	return ret;
+}
+
 static const struct rpc_authops generic_auth_ops = {
 	.owner = THIS_MODULE,
 	.au_name = "Generic",
 	.lookup_cred = generic_lookup_cred,
 	.crcreate = generic_create_cred,
+	.key_timeout = generic_key_timeout,
 };
 
 static struct rpc_auth generic_auth = {
@@ -194,9 +262,23 @@ static struct rpc_auth generic_auth = {
 	.au_count = ATOMIC_INIT(0),
 };
 
+static bool generic_key_to_expire(struct rpc_cred *cred)
+{
+	struct auth_cred *acred = &container_of(cred, struct generic_cred,
+						gc_base)->acred;
+	bool ret;
+
+	get_rpccred(cred);
+	ret = test_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
+	put_rpccred(cred);
+
+	return ret;
+}
+
 static const struct rpc_credops generic_credops = {
 	.cr_name = "Generic cred",
 	.crdestroy = generic_destroy_cred,
 	.crbind = generic_bind_cred,
 	.crmatch = generic_match,
+	.crkey_to_expire = generic_key_to_expire,
 };
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index dc4b449d3680..a9b1edca917c 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -63,6 +63,9 @@ static const struct rpc_credops gss_nullops;
 #define GSS_RETRY_EXPIRED 5
 static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED;
 
+#define GSS_KEY_EXPIRE_TIMEO 240
+static unsigned int gss_key_expire_timeo = GSS_KEY_EXPIRE_TIMEO;
+
 #ifdef RPC_DEBUG
 # define RPCDBG_FACILITY	RPCDBG_AUTH
 #endif
@@ -1295,10 +1298,32 @@ gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred)
 	return err;
 }
 
+/*
+ * Returns -EACCES if GSS context is NULL or will expire within the
+ * timeout (miliseconds)
+ */
+static int
+gss_key_timeout(struct rpc_cred *rc)
+{
+	struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
+	unsigned long now = jiffies;
+	unsigned long expire;
+
+	if (gss_cred->gc_ctx == NULL)
+		return -EACCES;
+
+	expire = gss_cred->gc_ctx->gc_expiry - (gss_key_expire_timeo * HZ);
+
+	if (time_after(now, expire))
+		return -EACCES;
+	return 0;
+}
+
 static int
 gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags)
 {
 	struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
+	int ret;
 
 	if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags))
 		goto out;
@@ -1311,11 +1336,26 @@ out:
 	if (acred->principal != NULL) {
 		if (gss_cred->gc_principal == NULL)
 			return 0;
-		return strcmp(acred->principal, gss_cred->gc_principal) == 0;
+		ret = strcmp(acred->principal, gss_cred->gc_principal) == 0;
+		goto check_expire;
 	}
 	if (gss_cred->gc_principal != NULL)
 		return 0;
-	return uid_eq(rc->cr_uid, acred->uid);
+	ret = uid_eq(rc->cr_uid, acred->uid);
+
+check_expire:
+	if (ret == 0)
+		return ret;
+
+	/* Notify acred users of GSS context expiration timeout */
+	if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags) &&
+	    (gss_key_timeout(rc) != 0)) {
+		/* test will now be done from generic cred */
+		test_and_clear_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
+		/* tell NFS layer that key will expire soon */
+		set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
+	}
+	return ret;
 }
 
 /*
@@ -1842,6 +1882,7 @@ static const struct rpc_credops gss_credops = {
 	.crvalidate	= gss_validate,
 	.crwrap_req	= gss_wrap_req,
 	.crunwrap_resp	= gss_unwrap_resp,
+	.crkey_timeout	= gss_key_timeout,
 };
 
 static const struct rpc_credops gss_nullops = {
@@ -1929,5 +1970,12 @@ module_param_named(expired_cred_retry_delay,
 MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until "
 		"the RPC engine retries an expired credential");
 
+module_param_named(key_expire_timeo,
+		   gss_key_expire_timeo,
+		   uint, 0644);
+MODULE_PARM_DESC(key_expire_timeo, "Time (in seconds) at the end of a "
+		"credential keys lifetime where the NFS layer cleans up "
+		"prior to key expiration");
+
 module_init(init_rpcsec_gss)
 module_exit(exit_rpcsec_gss)