xfrm: extend add state callback to set failure reason

Almost all validation logic is in the drivers, but they are
missing reliable way to convey failure reason to userspace
applications.

Let's use extack to return this information to users.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/networking/xfrm_device.rst

@@ -64,7 +64,7 @@ Callbacks to implement
   /* from include/linux/netdevice.h */
   struct xfrmdev_ops {
         /* Crypto and Packet offload callbacks */
-	int	(*xdo_dev_state_add) (struct xfrm_state *x);
+	int	(*xdo_dev_state_add) (struct xfrm_state *x, struct netlink_ext_ack *extack);
 	void	(*xdo_dev_state_delete) (struct xfrm_state *x);
 	void	(*xdo_dev_state_free) (struct xfrm_state *x);
 	bool	(*xdo_dev_offload_ok) (struct sk_buff *skb,

drivers/net/bonding/bond_main.c

@@ -419,8 +419,10 @@ static int bond_vlan_rx_kill_vid(struct net_device *bond_dev,
 /**
  * bond_ipsec_add_sa - program device with a security association
  * @xs: pointer to transformer state struct
+ * @extack: extack point to fill failure reason
  **/
-static int bond_ipsec_add_sa(struct xfrm_state *xs)
+static int bond_ipsec_add_sa(struct xfrm_state *xs,
+			     struct netlink_ext_ack *extack)
 {
 	struct net_device *bond_dev = xs->xso.dev;
 	struct bond_ipsec *ipsec;
@@ -454,7 +456,7 @@ static int bond_ipsec_add_sa(struct xfrm_state *xs)
 	}
 	xs->xso.real_dev = slave->dev;
 
-	err = slave->dev->xfrmdev_ops->xdo_dev_state_add(xs);
+	err = slave->dev->xfrmdev_ops->xdo_dev_state_add(xs, extack);
 	if (!err) {
 		ipsec->xs = xs;
 		INIT_LIST_HEAD(&ipsec->list);
@@ -494,7 +496,7 @@ static void bond_ipsec_add_sa_all(struct bonding *bond)
 	spin_lock_bh(&bond->ipsec_lock);
 	list_for_each_entry(ipsec, &bond->ipsec_list, list) {
 		ipsec->xs->xso.real_dev = slave->dev;
-		if (slave->dev->xfrmdev_ops->xdo_dev_state_add(ipsec->xs)) {
+		if (slave->dev->xfrmdev_ops->xdo_dev_state_add(ipsec->xs, NULL)) {
 			slave_warn(bond_dev, slave->dev, "%s: failed to add SA\n", __func__);
 			ipsec->xs->xso.real_dev = NULL;
 		}

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

@@ -6490,7 +6490,8 @@ static const struct tlsdev_ops cxgb4_ktls_ops = {
 
 #if IS_ENABLED(CONFIG_CHELSIO_IPSEC_INLINE)
 
-static int cxgb4_xfrm_add_state(struct xfrm_state *x)
+static int cxgb4_xfrm_add_state(struct xfrm_state *x,
+				struct netlink_ext_ack *extack)
 {
 	struct adapter *adap = netdev2adap(x->xso.dev);
 	int ret;
@@ -6504,7 +6505,7 @@ static int cxgb4_xfrm_add_state(struct xfrm_state *x)
 	if (ret)
 		goto out_unlock;
 
-	ret = adap->uld[CXGB4_ULD_IPSEC].xfrmdev_ops->xdo_dev_state_add(x);
+	ret = adap->uld[CXGB4_ULD_IPSEC].xfrmdev_ops->xdo_dev_state_add(x, extack);
 
 out_unlock:
 	mutex_unlock(&uld_mutex);

drivers/net/ethernet/chelsio/inline_crypto/ch_ipsec/chcr_ipsec.c

@@ -80,7 +80,8 @@ static void *ch_ipsec_uld_add(const struct cxgb4_lld_info *infop);
 static void ch_ipsec_advance_esn_state(struct xfrm_state *x);
 static void ch_ipsec_xfrm_free_state(struct xfrm_state *x);
 static void ch_ipsec_xfrm_del_state(struct xfrm_state *x);
-static int ch_ipsec_xfrm_add_state(struct xfrm_state *x);
+static int ch_ipsec_xfrm_add_state(struct xfrm_state *x,
+				   struct netlink_ext_ack *extack);
 
 static const struct xfrmdev_ops ch_ipsec_xfrmdev_ops = {
 	.xdo_dev_state_add      = ch_ipsec_xfrm_add_state,
@@ -226,7 +227,8 @@ static int ch_ipsec_setkey(struct xfrm_state *x,
  * returns 0 on success, negative error if failed to send message to FPGA
  * positive error if FPGA returned a bad response
  */
-static int ch_ipsec_xfrm_add_state(struct xfrm_state *x)
+static int ch_ipsec_xfrm_add_state(struct xfrm_state *x,
+				   struct netlink_ext_ack *extack)
 {
 	struct ipsec_sa_entry *sa_entry;
 	int res = 0;

drivers/net/ethernet/intel/ixgbe/ixgbe_ipsec.c

@@ -557,8 +557,10 @@ static int ixgbe_ipsec_check_mgmt_ip(struct xfrm_state *xs)
 /**
  * ixgbe_ipsec_add_sa - program device with a security association
  * @xs: pointer to transformer state struct
+ * @extack: extack point to fill failure reason
  **/
-static int ixgbe_ipsec_add_sa(struct xfrm_state *xs)
+static int ixgbe_ipsec_add_sa(struct xfrm_state *xs,
+			      struct netlink_ext_ack *extack)
 {
 	struct net_device *dev = xs->xso.real_dev;
 	struct ixgbe_adapter *adapter = netdev_priv(dev);
@@ -950,7 +952,7 @@ int ixgbe_ipsec_vf_add_sa(struct ixgbe_adapter *adapter, u32 *msgbuf, u32 vf)
 	memcpy(xs->aead->alg_name, aes_gcm_name, sizeof(aes_gcm_name));
 
 	/* set up the HW offload */
-	err = ixgbe_ipsec_add_sa(xs);
+	err = ixgbe_ipsec_add_sa(xs, NULL);
 	if (err)
 		goto err_aead;
 

drivers/net/ethernet/intel/ixgbevf/ipsec.c

@@ -257,8 +257,10 @@ static int ixgbevf_ipsec_parse_proto_keys(struct xfrm_state *xs,
 /**
  * ixgbevf_ipsec_add_sa - program device with a security association
  * @xs: pointer to transformer state struct
+ * @extack: extack point to fill failure reason
  **/
-static int ixgbevf_ipsec_add_sa(struct xfrm_state *xs)
+static int ixgbevf_ipsec_add_sa(struct xfrm_state *xs,
+				struct netlink_ext_ack *extack)
 {
 	struct net_device *dev = xs->xso.real_dev;
 	struct ixgbevf_adapter *adapter;

drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c

@@ -298,7 +298,8 @@ static void _update_xfrm_state(struct work_struct *work)
 	mlx5_accel_esp_modify_xfrm(sa_entry, &modify_work->attrs);
 }
 
-static int mlx5e_xfrm_add_state(struct xfrm_state *x)
+static int mlx5e_xfrm_add_state(struct xfrm_state *x,
+				struct netlink_ext_ack *extack)
 {
 	struct mlx5e_ipsec_sa_entry *sa_entry = NULL;
 	struct net_device *netdev = x->xso.real_dev;

drivers/net/ethernet/netronome/nfp/crypto/ipsec.c

@@ -260,7 +260,8 @@ static void set_sha2_512hmac(struct nfp_ipsec_cfg_add_sa *cfg, int *trunc_len)
 	}
 }
 
-static int nfp_net_xfrm_add_state(struct xfrm_state *x)
+static int nfp_net_xfrm_add_state(struct xfrm_state *x,
+				  struct netlink_ext_ack *extack)
 {
 	struct net_device *netdev = x->xso.dev;
 	struct nfp_ipsec_cfg_mssg msg = {};

drivers/net/netdevsim/ipsec.c

@@ -125,7 +125,8 @@ static int nsim_ipsec_parse_proto_keys(struct xfrm_state *xs,
 	return 0;
 }
 
-static int nsim_ipsec_add_sa(struct xfrm_state *xs)
+static int nsim_ipsec_add_sa(struct xfrm_state *xs,
+			     struct netlink_ext_ack *extack)
 {
 	struct nsim_ipsec *ipsec;
 	struct net_device *dev;

include/linux/netdevice.h

@@ -1035,7 +1035,7 @@ struct netdev_bpf {
 
 #ifdef CONFIG_XFRM_OFFLOAD
 struct xfrmdev_ops {
-	int	(*xdo_dev_state_add) (struct xfrm_state *x);
+	int	(*xdo_dev_state_add) (struct xfrm_state *x, struct netlink_ext_ack *extack);
 	void	(*xdo_dev_state_delete) (struct xfrm_state *x);
 	void	(*xdo_dev_state_free) (struct xfrm_state *x);
 	bool	(*xdo_dev_offload_ok) (struct sk_buff *skb,

net/xfrm/xfrm_device.c

@@ -309,7 +309,7 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 	else
 		xso->type = XFRM_DEV_OFFLOAD_CRYPTO;
 
-	err = dev->xfrmdev_ops->xdo_dev_state_add(x);
+	err = dev->xfrmdev_ops->xdo_dev_state_add(x, extack);
 	if (err) {
 		xso->dev = NULL;
 		xso->dir = 0;
@@ -325,10 +325,8 @@ int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
 		 * authors to do not return -EOPNOTSUPP in packet offload mode.
 		 */
 		WARN_ON(err == -EOPNOTSUPP && is_packet_offload);
-		if (err != -EOPNOTSUPP || is_packet_offload) {
-			NL_SET_ERR_MSG(extack, "Device failed to offload this state");
+		if (err != -EOPNOTSUPP || is_packet_offload)
 			return err;
-		}
 	}
 
 	return 0;

net/xfrm/xfrm_state.c

@@ -1274,7 +1274,7 @@ xfrm_state_find(const xfrm_address_t *daddr, const xfrm_address_t *saddr,
 			xso->real_dev = xdo->real_dev;
 			netdev_tracker_alloc(xso->dev, &xso->dev_tracker,
 					     GFP_ATOMIC);
-			error = xso->dev->xfrmdev_ops->xdo_dev_state_add(x);
+			error = xso->dev->xfrmdev_ops->xdo_dev_state_add(x, NULL);
 			if (error) {
 				xso->dir = 0;
 				netdev_put(xso->dev, &xso->dev_tracker);