/*
* Copyright (c) 2017 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 <crypto/aead.h>
#include <net/xfrm.h>
#include <net/esp.h>
#include "en_accel/ipsec_rxtx.h"
#include "en_accel/ipsec.h"
#include "accel/accel.h"
#include "en.h"
enum {
MLX5E_IPSEC_RX_SYNDROME_DECRYPTED = 0x11,
MLX5E_IPSEC_RX_SYNDROME_AUTH_FAILED = 0x12,
MLX5E_IPSEC_RX_SYNDROME_BAD_PROTO = 0x17,
};
struct mlx5e_ipsec_rx_metadata {
unsigned char nexthdr;
__be32 sa_handle;
} __packed;
enum {
MLX5E_IPSEC_TX_SYNDROME_OFFLOAD = 0x8,
MLX5E_IPSEC_TX_SYNDROME_OFFLOAD_WITH_LSO_TCP = 0x9,
};
struct mlx5e_ipsec_tx_metadata {
__be16 mss_inv; /* 1/MSS in 16bit fixed point, only for LSO */
__be16 seq; /* LSBs of the first TCP seq, only for LSO */
u8 esp_next_proto; /* Next protocol of ESP */
} __packed;
struct mlx5e_ipsec_metadata {
unsigned char syndrome;
union {
unsigned char raw[5];
/* from FPGA to host, on successful decrypt */
struct mlx5e_ipsec_rx_metadata rx;
/* from host to FPGA */
struct mlx5e_ipsec_tx_metadata tx;
} __packed content;
/* packet type ID field */
__be16 ethertype;
} __packed;
#define MAX_LSO_MSS 2048
/* Pre-calculated (Q0.16) fixed-point inverse 1/x function */
static __be16 mlx5e_ipsec_inverse_table[MAX_LSO_MSS];
static inline __be16 mlx5e_ipsec_mss_inv(struct sk_buff *skb)
{
return mlx5e_ipsec_inverse_table[skb_shinfo(skb)->gso_size];
}
static struct mlx5e_ipsec_metadata *mlx5e_ipsec_add_metadata(struct sk_buff *skb)
{
struct mlx5e_ipsec_metadata *mdata;
struct ethhdr *eth;
if (unlikely(skb_cow_head(skb, sizeof(*mdata))))
return ERR_PTR(-ENOMEM);
eth = (struct ethhdr *)skb_push(skb, sizeof(*mdata));
skb->mac_header -= sizeof(*mdata);
mdata = (struct mlx5e_ipsec_metadata *)(eth + 1);
memmove(skb->data, skb->data + sizeof(*mdata),
2 * ETH_ALEN);
eth->h_proto = cpu_to_be16(MLX5E_METADATA_ETHER_TYPE);
memset(mdata->content.raw, 0, sizeof(mdata->content.raw));
return mdata;
}
static int mlx5e_ipsec_remove_trailer(struct sk_buff *skb, struct xfrm_state *x)
{
unsigned int alen = crypto_aead_authsize(x->data);
struct ipv6hdr *ipv6hdr = ipv6_hdr(skb);
struct iphdr *ipv4hdr = ip_hdr(skb);
unsigned int trailer_len;
u8 plen;
int ret;
ret = skb_copy_bits(skb, skb->len - alen - 2, &plen, 1);
if (unlikely(ret))
return ret;
trailer_len = alen + plen + 2;
pskb_trim(skb, skb->len - trailer_len);
if (skb->protocol == htons(ETH_P_IP)) {
ipv4hdr->tot_len = htons(ntohs(ipv4hdr->tot_len) - trailer_len);
ip_send_check(ipv4hdr);
} else {
ipv6hdr->payload_len = htons(ntohs(ipv6hdr->payload_len) -
trailer_len);
}
return 0;
}
static void mlx5e_ipsec_set_swp(struct sk_buff *skb,
struct mlx5_wqe_eth_seg *eseg, u8 mode,
struct xfrm_offload *xo)
{
struct mlx5e_swp_spec swp_spec = {};
/* Tunnel Mode:
* SWP: OutL3 InL3 InL4
* Pkt: MAC IP ESP IP L4
*
* Transport Mode:
* SWP: OutL3 InL4
* InL3
* Pkt: MAC IP ESP L4
*/
swp_spec.l3_proto = skb->protocol;
swp_spec.is_tun = mode == XFRM_MODE_TUNNEL;
if (swp_spec.is_tun) {
if (xo->proto == IPPROTO_IPV6) {
swp_spec.tun_l3_proto = htons(ETH_P_IPV6);
swp_spec.tun_l4_proto = inner_ipv6_hdr(skb)->nexthdr;
} else {
swp_spec.tun_l3_proto = htons(ETH_P_IP);
swp_spec.tun_l4_proto = inner_ip_hdr(skb)->protocol;
}
} else {
swp_spec.tun_l3_proto = skb->protocol;
swp_spec.tun_l4_proto = xo->proto;
}
mlx5e_set_eseg_swp(skb, eseg, &swp_spec);
}
void mlx5e_ipsec_set_iv_esn(struct sk_buff *skb, struct xfrm_state *x,
struct xfrm_offload *xo)
{
struct xfrm_replay_state_esn *replay_esn = x->replay_esn;
__u32 oseq = replay_esn->oseq;
int iv_offset;
__be64 seqno;
u32 seq_hi;
if (unlikely(skb_is_gso(skb) && oseq < MLX5E_IPSEC_ESN_SCOPE_MID &&
MLX5E_IPSEC_ESN_SCOPE_MID < (oseq - skb_shinfo(skb)->gso_segs))) {
seq_hi = xo->seq.hi - 1;
} else {
seq_hi = xo->seq.hi;
}
/* Place the SN in the IV field */
seqno = cpu_to_be64(xo->seq.low + ((u64)seq_hi << 32));
iv_offset = skb_transport_offset(skb) + sizeof(struct ip_esp_hdr);
skb_store_bits(skb, iv_offset, &seqno, 8);
}
void mlx5e_ipsec_set_iv(struct sk_buff *skb, struct xfrm_state *x,
struct xfrm_offload *xo)
{
int iv_offset;
__be64 seqno;
/* Place the SN in the IV field */
seqno = cpu_to_be64(xo->seq.low + ((u64)xo->seq.hi << 32));
iv_offset = skb_transport_offset(skb) + sizeof(struct ip_esp_hdr);
skb_store_bits(skb, iv_offset, &seqno, 8);
}
static void mlx5e_ipsec_set_metadata(struct sk_buff *skb,
struct mlx5e_ipsec_metadata *mdata,
struct xfrm_offload *xo)
{
struct ip_esp_hdr *esph;
struct tcphdr *tcph;
if (skb_is_gso(skb)) {
/* Add LSO metadata indication */
esph = ip_esp_hdr(skb);
tcph = inner_tcp_hdr(skb);
netdev_dbg(skb->dev, " Offloading GSO packet outer L3 %u; L4 %u; Inner L3 %u; L4 %u\n",
skb->network_header,
skb->transport_header,
skb->inner_network_header,
skb->inner_transport_header);
netdev_dbg(skb->dev, " Offloading GSO packet of len %u; mss %u; TCP sp %u dp %u seq 0x%x ESP seq 0x%x\n",
skb->len, skb_shinfo(skb)->gso_size,
ntohs(tcph->source), ntohs(tcph->dest),
ntohl(tcph->seq), ntohl(esph->seq_no));
mdata->syndrome = MLX5E_IPSEC_TX_SYNDROME_OFFLOAD_WITH_LSO_TCP;
mdata->content.tx.mss_inv = mlx5e_ipsec_mss_inv(skb);
mdata->content.tx.seq = htons(ntohl(tcph->seq) & 0xFFFF);
} else {
mdata->syndrome = MLX5E_IPSEC_TX_SYNDROME_OFFLOAD;
}
mdata->content.tx.esp_next_proto = xo->proto;
netdev_dbg(skb->dev, " TX metadata syndrome %u proto %u mss_inv %04x seq %04x\n",
mdata->syndrome, mdata->content.tx.esp_next_proto,
ntohs(mdata->content.tx.mss_inv),
ntohs(mdata->content.tx.seq));
}
struct sk_buff *mlx5e_ipsec_handle_tx_skb(struct net_device *netdev,
struct mlx5e_tx_wqe *wqe,
struct sk_buff *skb)
{
struct mlx5e_priv *priv = netdev_priv(netdev);
struct xfrm_offload *xo = xfrm_offload(skb);
struct mlx5e_ipsec_metadata *mdata;
struct mlx5e_ipsec_sa_entry *sa_entry;
struct xfrm_state *x;
struct sec_path *sp;
if (!xo)
return skb;
sp = skb_sec_path(skb);
if (unlikely(sp->len != 1)) {
atomic64_inc(&priv->ipsec->sw_stats.ipsec_tx_drop_bundle);
goto drop;
}
x = xfrm_input_state(skb);
if (unlikely(!x)) {
atomic64_inc(&priv->ipsec->sw_stats.ipsec_tx_drop_no_state);
goto drop;
}
if (unlikely(!x->xso.offload_handle ||
(skb->protocol != htons(ETH_P_IP) &&
skb->protocol != htons(ETH_P_IPV6)))) {
atomic64_inc(&priv->ipsec->sw_stats.ipsec_tx_drop_not_ip);
goto drop;
}
if (!skb_is_gso(skb))
if (unlikely(mlx5e_ipsec_remove_trailer(skb, x))) {
atomic64_inc(&priv->ipsec->sw_stats.ipsec_tx_drop_trailer);
goto drop;
}
mdata = mlx5e_ipsec_add_metadata(skb);
if (IS_ERR(mdata)) {
atomic64_inc(&priv->ipsec->sw_stats.ipsec_tx_drop_metadata);
goto drop;
}
mlx5e_ipsec_set_swp(skb, &wqe->eth, x->props.mode, xo);
sa_entry = (struct mlx5e_ipsec_sa_entry *)x->xso.offload_handle;
sa_entry->set_iv_op(skb, x, xo);
mlx5e_ipsec_set_metadata(skb, mdata, xo);
return skb;
drop:
kfree_skb(skb);
return NULL;
}
static inline struct xfrm_state *
mlx5e_ipsec_build_sp(struct net_device *netdev, struct sk_buff *skb,
struct mlx5e_ipsec_metadata *mdata)
{
struct mlx5e_priv *priv = netdev_priv(netdev);
struct xfrm_offload *xo;
struct xfrm_state *xs;
struct sec_path *sp;
u32 sa_handle;
sp = secpath_set(skb);
if (unlikely(!sp)) {
atomic64_inc(&priv->ipsec->sw_stats.ipsec_rx_drop_sp_alloc);
return NULL;
}
sa_handle = be32_to_cpu(mdata->content.rx.sa_handle);
xs = mlx5e_ipsec_sadb_rx_lookup(priv->ipsec, sa_handle);
if (unlikely(!xs)) {
atomic64_inc(&priv->ipsec->sw_stats.ipsec_rx_drop_sadb_miss);
return NULL;
}
sp = skb_sec_path(skb);
sp->xvec[sp->len++] = xs;
sp->olen++;
xo = xfrm_offload(skb);
xo->flags = CRYPTO_DONE;
switch (mdata->syndrome) {
case MLX5E_IPSEC_RX_SYNDROME_DECRYPTED:
xo->status = CRYPTO_SUCCESS;
if (likely(priv->ipsec->no_trailer)) {
xo->flags |= XFRM_ESP_NO_TRAILER;
xo->proto = mdata->content.rx.nexthdr;
}
break;
case MLX5E_IPSEC_RX_SYNDROME_AUTH_FAILED:
xo->status = CRYPTO_TUNNEL_ESP_AUTH_FAILED;
break;
case MLX5E_IPSEC_RX_SYNDROME_BAD_PROTO:
xo->status = CRYPTO_INVALID_PROTOCOL;
break;
default:
atomic64_inc(&priv->ipsec->sw_stats.ipsec_rx_drop_syndrome);
return NULL;
}
return xs;
}
struct sk_buff *mlx5e_ipsec_handle_rx_skb(struct net_device *netdev,
struct sk_buff *skb, u32 *cqe_bcnt)
{
struct mlx5e_ipsec_metadata *mdata;
struct xfrm_state *xs;
if (!is_metadata_hdr_valid(skb))
return skb;
/* Use the metadata */
mdata = (struct mlx5e_ipsec_metadata *)(skb->data + ETH_HLEN);
xs = mlx5e_ipsec_build_sp(netdev, skb, mdata);
if (unlikely(!xs)) {
kfree_skb(skb);
return NULL;
}
remove_metadata_hdr(skb);
*cqe_bcnt -= MLX5E_METADATA_ETHER_LEN;
return skb;
}
bool mlx5e_ipsec_feature_check(struct sk_buff *skb, struct net_device *netdev,
netdev_features_t features)
{
struct sec_path *sp = skb_sec_path(skb);
struct xfrm_state *x;
if (sp && sp->len) {
x = sp->xvec[0];
if (x && x->xso.offload_handle)
return true;
}
return false;
}
void mlx5e_ipsec_build_inverse_table(void)
{
u16 mss_inv;
u32 mss;
/* Calculate 1/x inverse table for use in GSO data path.
* Using this table, we provide the IPSec accelerator with the value of
* 1/gso_size so that it can infer the position of each segment inside
* the GSO, and increment the ESP sequence number, and generate the IV.
* The HW needs this value in Q0.16 fixed-point number format
*/
mlx5e_ipsec_inverse_table[1] = htons(0xFFFF);
for (mss = 2; mss < MAX_LSO_MSS; mss++) {
mss_inv = div_u64(1ULL << 32, mss) >> 16;
mlx5e_ipsec_inverse_table[mss] = htons(mss_inv);
}
}
