net/mlx5e: TLS, Add Innova TLS TX offload data path

Implement the TLS tx offload data path according to the
requirements of the TLS generic NIC offload infrastructure.

Special metadata ethertype is used to pass information to
the hardware.

Signed-off-by: Ilya Lesokhin <[email protected]>
Signed-off-by: Boris Pismenny <[email protected]>
Acked-by: Saeed Mahameed <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: Ilya Lesokhin

drivers/net/ethernet/mellanox/mlx5/core/Makefile

@@ -28,6 +28,6 @@ mlx5_core-$(CONFIG_MLX5_CORE_IPOIB) += ipoib/ipoib.o ipoib/ethtool.o ipoib/ipoib
 mlx5_core-$(CONFIG_MLX5_EN_IPSEC) += en_accel/ipsec.o en_accel/ipsec_rxtx.o \
 		en_accel/ipsec_stats.o
 
-mlx5_core-$(CONFIG_MLX5_EN_TLS) +=  en_accel/tls.o
+mlx5_core-$(CONFIG_MLX5_EN_TLS) +=  en_accel/tls.o en_accel/tls_rxtx.o
 
 CFLAGS_tracepoint.o := -I$(src)

drivers/net/ethernet/mellanox/mlx5/core/en.h

@@ -335,6 +335,7 @@ enum {
 	MLX5E_SQ_STATE_RECOVERING,
 	MLX5E_SQ_STATE_IPSEC,
 	MLX5E_SQ_STATE_AM,
+	MLX5E_SQ_STATE_TLS,
 };
 
 struct mlx5e_sq_wqe_info {
@@ -830,6 +831,8 @@ void mlx5e_build_ptys2ethtool_map(void);
 u16 mlx5e_select_queue(struct net_device *dev, struct sk_buff *skb,
 		       void *accel_priv, select_queue_fallback_t fallback);
 netdev_tx_t mlx5e_xmit(struct sk_buff *skb, struct net_device *dev);
+netdev_tx_t mlx5e_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
+			  struct mlx5e_tx_wqe *wqe, u16 pi);
 
 void mlx5e_completion_event(struct mlx5_core_cq *mcq);
 void mlx5e_cq_error_event(struct mlx5_core_cq *mcq, enum mlx5_event event);
@@ -945,6 +948,18 @@ static inline bool mlx5e_tunnel_inner_ft_supported(struct mlx5_core_dev *mdev)
 		MLX5_CAP_FLOWTABLE_NIC_RX(mdev, ft_field_support.inner_ip_version));
 }
 
+static inline void mlx5e_sq_fetch_wqe(struct mlx5e_txqsq *sq,
+				      struct mlx5e_tx_wqe **wqe,
+				      u16 *pi)
+{
+	struct mlx5_wq_cyc *wq;
+
+	wq = &sq->wq;
+	*pi = sq->pc & wq->sz_m1;
+	*wqe = mlx5_wq_cyc_get_wqe(wq, *pi);
+	memset(*wqe, 0, sizeof(**wqe));
+}
+
 static inline
 struct mlx5e_tx_wqe *mlx5e_post_nop(struct mlx5_wq_cyc *wq, u32 sqn, u16 *pc)
 {

drivers/net/ethernet/mellanox/mlx5/core/en_accel/en_accel.h

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#ifndef __MLX5E_EN_ACCEL_H__
+#define __MLX5E_EN_ACCEL_H__
+
+#ifdef CONFIG_MLX5_ACCEL
+
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include "en_accel/ipsec_rxtx.h"
+#include "en_accel/tls_rxtx.h"
+#include "en.h"
+
+static inline struct sk_buff *mlx5e_accel_handle_tx(struct sk_buff *skb,
+						    struct mlx5e_txqsq *sq,
+						    struct net_device *dev,
+						    struct mlx5e_tx_wqe **wqe,
+						    u16 *pi)
+{
+#ifdef CONFIG_MLX5_EN_TLS
+	if (sq->state & BIT(MLX5E_SQ_STATE_TLS)) {
+		skb = mlx5e_tls_handle_tx_skb(dev, sq, skb, wqe, pi);
+		if (unlikely(!skb))
+			return NULL;
+	}
+#endif
+
+#ifdef CONFIG_MLX5_EN_IPSEC
+	if (sq->state & BIT(MLX5E_SQ_STATE_IPSEC)) {
+		skb = mlx5e_ipsec_handle_tx_skb(dev, *wqe, skb);
+		if (unlikely(!skb))
+			return NULL;
+	}
+#endif
+
+	return skb;
+}
+
+#endif /* CONFIG_MLX5_ACCEL */
+
+#endif /* __MLX5E_EN_ACCEL_H__ */

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

@@ -169,5 +169,7 @@ void mlx5e_tls_build_netdev(struct mlx5e_priv *priv)
 	if (!mlx5_accel_is_tls_device(priv->mdev))
 		return;
 
+	netdev->features |= NETIF_F_HW_TLS_TX;
+	netdev->hw_features |= NETIF_F_HW_TLS_TX;
 	netdev->tlsdev_ops = &mlx5e_tls_ops;
 }

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

@@ -0,0 +1,272 @@
+/*
+ * Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#include "en_accel/tls.h"
+#include "en_accel/tls_rxtx.h"
+
+#define SYNDROME_OFFLOAD_REQUIRED 32
+#define SYNDROME_SYNC 33
+
+struct sync_info {
+	u64 rcd_sn;
+	s32 sync_len;
+	int nr_frags;
+	skb_frag_t frags[MAX_SKB_FRAGS];
+};
+
+struct mlx5e_tls_metadata {
+	/* One byte of syndrome followed by 3 bytes of swid */
+	__be32 syndrome_swid;
+	__be16 first_seq;
+	/* packet type ID field	*/
+	__be16 ethertype;
+} __packed;
+
+static int mlx5e_tls_add_metadata(struct sk_buff *skb, __be32 swid)
+{
+	struct mlx5e_tls_metadata *pet;
+	struct ethhdr *eth;
+
+	if (skb_cow_head(skb, sizeof(struct mlx5e_tls_metadata)))
+		return -ENOMEM;
+
+	eth = (struct ethhdr *)skb_push(skb, sizeof(struct mlx5e_tls_metadata));
+	skb->mac_header -= sizeof(struct mlx5e_tls_metadata);
+	pet = (struct mlx5e_tls_metadata *)(eth + 1);
+
+	memmove(skb->data, skb->data + sizeof(struct mlx5e_tls_metadata),
+		2 * ETH_ALEN);
+
+	eth->h_proto = cpu_to_be16(MLX5E_METADATA_ETHER_TYPE);
+	pet->syndrome_swid = htonl(SYNDROME_OFFLOAD_REQUIRED << 24) | swid;
+
+	return 0;
+}
+
+static int mlx5e_tls_get_sync_data(struct mlx5e_tls_offload_context *context,
+				   u32 tcp_seq, struct sync_info *info)
+{
+	int remaining, i = 0, ret = -EINVAL;
+	struct tls_record_info *record;
+	unsigned long flags;
+	s32 sync_size;
+
+	spin_lock_irqsave(&context->base.lock, flags);
+	record = tls_get_record(&context->base, tcp_seq, &info->rcd_sn);
+
+	if (unlikely(!record))
+		goto out;
+
+	sync_size = tcp_seq - tls_record_start_seq(record);
+	info->sync_len = sync_size;
+	if (unlikely(sync_size < 0)) {
+		if (tls_record_is_start_marker(record))
+			goto done;
+
+		goto out;
+	}
+
+	remaining = sync_size;
+	while (remaining > 0) {
+		info->frags[i] = record->frags[i];
+		__skb_frag_ref(&info->frags[i]);
+		remaining -= skb_frag_size(&info->frags[i]);
+
+		if (remaining < 0)
+			skb_frag_size_add(&info->frags[i], remaining);
+
+		i++;
+	}
+	info->nr_frags = i;
+done:
+	ret = 0;
+out:
+	spin_unlock_irqrestore(&context->base.lock, flags);
+	return ret;
+}
+
+static void mlx5e_tls_complete_sync_skb(struct sk_buff *skb,
+					struct sk_buff *nskb, u32 tcp_seq,
+					int headln, __be64 rcd_sn)
+{
+	struct mlx5e_tls_metadata *pet;
+	u8 syndrome = SYNDROME_SYNC;
+	struct iphdr *iph;
+	struct tcphdr *th;
+	int data_len, mss;
+
+	nskb->dev = skb->dev;
+	skb_reset_mac_header(nskb);
+	skb_set_network_header(nskb, skb_network_offset(skb));
+	skb_set_transport_header(nskb, skb_transport_offset(skb));
+	memcpy(nskb->data, skb->data, headln);
+	memcpy(nskb->data + headln, &rcd_sn, sizeof(rcd_sn));
+
+	iph = ip_hdr(nskb);
+	iph->tot_len = htons(nskb->len - skb_network_offset(nskb));
+	th = tcp_hdr(nskb);
+	data_len = nskb->len - headln;
+	tcp_seq -= data_len;
+	th->seq = htonl(tcp_seq);
+
+	mss = nskb->dev->mtu - (headln - skb_network_offset(nskb));
+	skb_shinfo(nskb)->gso_size = 0;
+	if (data_len > mss) {
+		skb_shinfo(nskb)->gso_size = mss;
+		skb_shinfo(nskb)->gso_segs = DIV_ROUND_UP(data_len, mss);
+	}
+	skb_shinfo(nskb)->gso_type = skb_shinfo(skb)->gso_type;
+
+	pet = (struct mlx5e_tls_metadata *)(nskb->data + sizeof(struct ethhdr));
+	memcpy(pet, &syndrome, sizeof(syndrome));
+	pet->first_seq = htons(tcp_seq);
+
+	/* MLX5 devices don't care about the checksum partial start, offset
+	 * and pseudo header
+	 */
+	nskb->ip_summed = CHECKSUM_PARTIAL;
+
+	nskb->xmit_more = 1;
+	nskb->queue_mapping = skb->queue_mapping;
+}
+
+static struct sk_buff *
+mlx5e_tls_handle_ooo(struct mlx5e_tls_offload_context *context,
+		     struct mlx5e_txqsq *sq, struct sk_buff *skb,
+		     struct mlx5e_tx_wqe **wqe,
+		     u16 *pi)
+{
+	u32 tcp_seq = ntohl(tcp_hdr(skb)->seq);
+	struct sync_info info;
+	struct sk_buff *nskb;
+	int linear_len = 0;
+	int headln;
+	int i;
+
+	sq->stats.tls_ooo++;
+
+	if (mlx5e_tls_get_sync_data(context, tcp_seq, &info))
+		/* We might get here if a retransmission reaches the driver
+		 * after the relevant record is acked.
+		 * It should be safe to drop the packet in this case
+		 */
+		goto err_out;
+
+	if (unlikely(info.sync_len < 0)) {
+		u32 payload;
+
+		headln = skb_transport_offset(skb) + tcp_hdrlen(skb);
+		payload = skb->len - headln;
+		if (likely(payload <= -info.sync_len))
+			/* SKB payload doesn't require offload
+			 */
+			return skb;
+
+		netdev_err(skb->dev,
+			   "Can't offload from the middle of an SKB [seq: %X, offload_seq: %X, end_seq: %X]\n",
+			   tcp_seq, tcp_seq + payload + info.sync_len,
+			   tcp_seq + payload);
+		goto err_out;
+	}
+
+	if (unlikely(mlx5e_tls_add_metadata(skb, context->swid)))
+		goto err_out;
+
+	headln = skb_transport_offset(skb) + tcp_hdrlen(skb);
+	linear_len += headln + sizeof(info.rcd_sn);
+	nskb = alloc_skb(linear_len, GFP_ATOMIC);
+	if (unlikely(!nskb))
+		goto err_out;
+
+	context->expected_seq = tcp_seq + skb->len - headln;
+	skb_put(nskb, linear_len);
+	for (i = 0; i < info.nr_frags; i++)
+		skb_shinfo(nskb)->frags[i] = info.frags[i];
+
+	skb_shinfo(nskb)->nr_frags = info.nr_frags;
+	nskb->data_len = info.sync_len;
+	nskb->len += info.sync_len;
+	sq->stats.tls_resync_bytes += nskb->len;
+	mlx5e_tls_complete_sync_skb(skb, nskb, tcp_seq, headln,
+				    cpu_to_be64(info.rcd_sn));
+	mlx5e_sq_xmit(sq, nskb, *wqe, *pi);
+	mlx5e_sq_fetch_wqe(sq, wqe, pi);
+	return skb;
+
+err_out:
+	dev_kfree_skb_any(skb);
+	return NULL;
+}
+
+struct sk_buff *mlx5e_tls_handle_tx_skb(struct net_device *netdev,
+					struct mlx5e_txqsq *sq,
+					struct sk_buff *skb,
+					struct mlx5e_tx_wqe **wqe,
+					u16 *pi)
+{
+	struct mlx5e_tls_offload_context *context;
+	struct tls_context *tls_ctx;
+	u32 expected_seq;
+	int datalen;
+	u32 skb_seq;
+
+	if (!skb->sk || !tls_is_sk_tx_device_offloaded(skb->sk))
+		goto out;
+
+	datalen = skb->len - (skb_transport_offset(skb) + tcp_hdrlen(skb));
+	if (!datalen)
+		goto out;
+
+	tls_ctx = tls_get_ctx(skb->sk);
+	if (unlikely(tls_ctx->netdev != netdev))
+		goto out;
+
+	skb_seq = ntohl(tcp_hdr(skb)->seq);
+	context = mlx5e_get_tls_tx_context(tls_ctx);
+	expected_seq = context->expected_seq;
+
+	if (unlikely(expected_seq != skb_seq)) {
+		skb = mlx5e_tls_handle_ooo(context, sq, skb, wqe, pi);
+		goto out;
+	}
+
+	if (unlikely(mlx5e_tls_add_metadata(skb, context->swid))) {
+		dev_kfree_skb_any(skb);
+		skb = NULL;
+		goto out;
+	}
+
+	context->expected_seq = skb_seq + datalen;
+out:
+	return skb;
+}