Subject: Re: [PATCH net-next v2 3/3] nfp: implement xfrm callbacks and expose ipsec offload feature to upper layer

From: Leon Romanovsky <[email-masked]>
Date: Thu, 29 Sep 2022 11:26:24 +0300

On Tue, Sep 27, 2022 at 12:27:07PM +0200, Simon Horman wrote:
> From: Huanhuan Wang <[email-masked]>
> 
> Xfrm callbacks are implemented to offload SA info into firmware
> by mailbox. It supports 16K SA info in total.
> 
> Expose ipsec offload feature to upper layer, this feature will
> signal the availability of the offload.
> 
> Based on initial work of Norm Bagley <[email-masked]>.
> 
> Signed-off-by: Huanhuan Wang <[email-masked]>
> Signed-off-by: Simon Horman <[email-masked]>
> ---
>  .../net/ethernet/netronome/nfp/crypto/ipsec.c | 562 +++++++++++++++++-
>  .../ethernet/netronome/nfp/nfp_net_common.c   |   6 +
>  .../net/ethernet/netronome/nfp/nfp_net_ctrl.h |   4 +-
>  3 files changed, 568 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/netronome/nfp/crypto/ipsec.c b/drivers/net/ethernet/netronome/nfp/crypto/ipsec.c
> index 658fcba8e733..a81e6cde4ea8 100644
> --- a/drivers/net/ethernet/netronome/nfp/crypto/ipsec.c
> +++ b/drivers/net/ethernet/netronome/nfp/crypto/ipsec.c
> @@ -17,6 +17,77 @@
>  #define NFP_NET_IPSEC_MAX_SA_CNT  (16 * 1024) /* Firmware support a maximum of 16K sa offload */
>  #define OFFLOAD_HANDLE_ERROR      0xffffffff
>  
> +/* IPsec config message cmd codes */
> +enum nfp_ipsec_cfg_mssg_cmd_codes {
> +	NFP_IPSEC_CFG_MSSG_ADD_SA,	 /* Add a new SA */
> +	NFP_IPSEC_CFG_MSSG_INV_SA,	 /* Invalidate an existing SA */
> +	NFP_IPSEC_CFG_MSSG_MODIFY_SA,	 /* Modify an existing SA */
> +	NFP_IPSEC_CFG_MSSG_GET_SA_STATS, /* Report SA counters, flags, etc. */
> +	NFP_IPSEC_CFG_MSSG_GET_SEQ_NUMS, /* Allocate sequence numbers */
> +	NFP_IPSEC_CFG_MSSG_LAST
> +};
> +
> +/* IPsec config message response codes */
> +enum nfp_ipsec_cfg_mssg_rsp_codes {
> +	NFP_IPSEC_CFG_MSSG_OK,
> +	NFP_IPSEC_CFG_MSSG_FAILED,
> +	NFP_IPSEC_CFG_MSSG_SA_VALID,
> +	NFP_IPSEC_CFG_MSSG_SA_HASH_ADD_FAILED,
> +	NFP_IPSEC_CFG_MSSG_SA_HASH_DEL_FAILED,
> +	NFP_IPSEC_CFG_MSSG_SA_INVALID_CMD
> +};
> +
> +/* Protocol */
> +enum nfp_ipsec_sa_prot {
> +	NFP_IPSEC_PROTOCOL_AH = 0,
> +	NFP_IPSEC_PROTOCOL_ESP = 1
> +};
> +
> +/* Mode */
> +enum nfp_ipsec_sa_mode {
> +	NFP_IPSEC_PROTMODE_TRANSPORT = 0,
> +	NFP_IPSEC_PROTMODE_TUNNEL = 1
> +};
> +
> +/* Cipher types */
> +enum nfp_ipsec_sa_cipher {
> +	NFP_IPSEC_CIPHER_NULL,
> +	NFP_IPSEC_CIPHER_3DES,
> +	NFP_IPSEC_CIPHER_AES128,
> +	NFP_IPSEC_CIPHER_AES192,
> +	NFP_IPSEC_CIPHER_AES256,
> +	NFP_IPSEC_CIPHER_AES128_NULL,
> +	NFP_IPSEC_CIPHER_AES192_NULL,
> +	NFP_IPSEC_CIPHER_AES256_NULL,
> +	NFP_IPSEC_CIPHER_CHACHA20
> +};
> +
> +/* Cipher modes */
> +enum nfp_ipsec_sa_cipher_mode {
> +	NFP_IPSEC_CIMODE_ECB,
> +	NFP_IPSEC_CIMODE_CBC,
> +	NFP_IPSEC_CIMODE_CFB,
> +	NFP_IPSEC_CIMODE_OFB,
> +	NFP_IPSEC_CIMODE_CTR
> +};
> +
> +/* Hash types */
> +enum nfp_ipsec_sa_hash_type {
> +	NFP_IPSEC_HASH_NONE,
> +	NFP_IPSEC_HASH_MD5_96,
> +	NFP_IPSEC_HASH_SHA1_96,
> +	NFP_IPSEC_HASH_SHA256_96,
> +	NFP_IPSEC_HASH_SHA384_96,
> +	NFP_IPSEC_HASH_SHA512_96,
> +	NFP_IPSEC_HASH_MD5_128,
> +	NFP_IPSEC_HASH_SHA1_80,
> +	NFP_IPSEC_HASH_SHA256_128,
> +	NFP_IPSEC_HASH_SHA384_192,
> +	NFP_IPSEC_HASH_SHA512_256,
> +	NFP_IPSEC_HASH_GF128_128,
> +	NFP_IPSEC_HASH_POLY1305_128
> +};
> +
>  /* IPSEC_CFG_MSSG_ADD_SA */
>  struct nfp_ipsec_cfg_add_sa {
>  	u32 ciph_key[8];		  /* Cipher Key */
> @@ -71,6 +142,73 @@ struct nfp_ipsec_cfg_add_sa {
>  	uint32_t tfc_padding :16;	  /* Traffic Flow Confidential Pad */
>  };
>  
> +/* IPSEC_CFG_MSSG_INV_SA */
> +struct nfp_ipsec_cfg_inv_sa {
> +	u32 spare6;
> +};
> +
> +/* IPSEC_CFG_MSSG_GET_SA_STATS */
> +struct nfp_ipsec_cfg_get_sa_stats {
> +	u32 seq_lo;					/* Sequence Number (low 32bits) */
> +	u32 seq_high;					/* Sequence Number (high 32bits) */
> +	u32 arw_counter_lo;				/* Anti-replay wndw cntr */
> +	u32 arw_counter_high;				/* Anti-replay wndw cntr */
> +	u32 arw_bitmap_lo;				/* Anti-replay wndw bitmap */
> +	u32 arw_bitmap_high;				/* Anti-replay wndw bitmap */
> +	uint32_t reserved1:1;
> +	uint32_t soft_lifetime_byte_cnt_exceeded :1;	/* Soft cnt_exceeded */
> +	uint32_t hard_lifetime_byte_cnt_exceeded :1;	/* Hard cnt_exceeded */
> +	uint32_t soft_lifetime_time_limit_exceeded :1;	/* Soft cnt_exceeded */
> +	uint32_t hard_lifetime_time_limit_exceeded :1;	/* Hard cnt_exceeded */
> +	uint32_t spare7:27;
> +	u32 lifetime_byte_count;
> +	u32 pkt_count;
> +	u32 discards_auth;				/* Auth failures */
> +	u32 discards_unsupported;			/* Unsupported crypto mode */
> +	u32 discards_alignment;				/* Alignment error */
> +	u32 discards_hard_bytelimit;			/* Byte Count limit */
> +	u32 discards_seq_num_wrap;			/* Sequ Number wrap */
> +	u32 discards_pmtu_limit_exceeded;		/* PMTU Limit */
> +	u32 discards_arw_old_seq;			/* Anti-Replay seq small */
> +	u32 discards_arw_replay;			/* Anti-Replay seq rcvd */
> +	u32 discards_ctrl_word;				/* Bad SA Control word */
> +	u32 discards_ip_hdr_len;			/* Hdr offset from too high */
> +	u32 discards_eop_buf;				/* No EOP buffer */
> +	u32 ipv4_id_counter;				/* IPv4 ID field counter */
> +	u32 discards_isl_fail;				/* Inbound SPD Lookup failure */
> +	u32 discards_ext_not_found;			/* Ext header end */
> +	u32 discards_max_ext_hdrs;			/* Max ext header */
> +	u32 discards_non_ext_hdrs;			/* Non-extension headers */
> +	u32 discards_ext_hdr_too_big;			/* Ext header chain */
> +	u32 discards_hard_timelimit;			/* Time Limit */
> +};
> +
> +/* IPSEC_CFG_MSSG_GET_SEQ_NUMS */
> +struct ipsec_cfg_get_seq_nums {
> +	u32 seq_nums;	 /* Sequence numbers to allocate */
> +	u32 seq_num_low; /* Rtrn start seq num 31:00 */
> +	u32 seq_num_hi;	 /* Rtrn start seq num 63:32 */
> +};
> +
> +/* IPSEC_CFG_MSSG */
> +struct nfp_ipsec_cfg_mssg {
> +	union {
> +		struct{
> +			uint32_t cmd:16;     /* One of nfp_ipsec_cfg_mssg_cmd_codes */
> +			uint32_t rsp:16;     /* One of nfp_ipsec_cfg_mssg_rsp_codes */
> +			uint32_t sa_idx:16;  /* SA table index */
> +			uint32_t spare0:16;
> +			union {
> +				struct nfp_ipsec_cfg_add_sa cfg_add_sa;
> +				struct nfp_ipsec_cfg_inv_sa cfg_inv_sa;
> +				struct nfp_ipsec_cfg_get_sa_stats cfg_get_stats;
> +				struct ipsec_cfg_get_seq_nums cfg_get_seq_nums;
> +			};
> +		};
> +		u32 raw[64];
> +	};
> +};
> +
>  struct nfp_net_ipsec_sa_data {
>  	struct nfp_ipsec_cfg_add_sa nfp_sa;
>  	struct xfrm_state *x;
> @@ -84,22 +222,442 @@ struct nfp_net_ipsec_data {
>  	struct mutex lock;	/* Protects nfp_net_ipsec_data struct */
>  };
>  
> +static int nfp_ipsec_cfg_cmd_issue(struct nfp_net *nn, int type, int saidx,
> +				   struct nfp_ipsec_cfg_mssg *msg)
> +{
> +	int i, msg_size, ret;
> +
> +	msg->cmd = type;
> +	msg->sa_idx = saidx;
> +	msg->rsp = 0;
> +	msg_size = ARRAY_SIZE(msg->raw);
> +
> +	for (i = 0; i < msg_size; i++)
> +		nn_writel(nn, NFP_NET_CFG_MBOX_VAL + 4 * i, msg->raw[i]);
> +
> +	ret = nfp_net_mbox_reconfig(nn, NFP_NET_CFG_MBOX_CMD_IPSEC);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* For now we always read the whole message response back */
> +	for (i = 0; i < msg_size; i++)
> +		msg->raw[i] = nn_readl(nn, NFP_NET_CFG_MBOX_VAL + 4 * i);
> +
> +	switch (msg->rsp) {
> +	case NFP_IPSEC_CFG_MSSG_OK:
> +		return 0;
> +	case NFP_IPSEC_CFG_MSSG_SA_INVALID_CMD:
> +		return -EINVAL;
> +	case NFP_IPSEC_CFG_MSSG_SA_VALID:
> +		return -EEXIST;
> +	case NFP_IPSEC_CFG_MSSG_FAILED:
> +	case NFP_IPSEC_CFG_MSSG_SA_HASH_ADD_FAILED:
> +	case NFP_IPSEC_CFG_MSSG_SA_HASH_DEL_FAILED:
> +		return -EIO;
> +	default:
> +		return -EDOM;
> +	}
> +}
> +
> +static int set_aes_keylen(struct nfp_ipsec_cfg_add_sa *cfg, int alg, int keylen)
> +{
> +	if (alg == SADB_X_EALG_NULL_AES_GMAC) {
> +		if (keylen == 128)
> +			cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_AES128_NULL;
> +		else if (keylen == 192)
> +			cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_AES192_NULL;
> +		else if (keylen == 256)
> +			cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_AES256_NULL;
> +		else
> +			return -EINVAL;
> +	} else {
> +		if (keylen == 128)
> +			cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_AES128;
> +		else if (keylen == 192)
> +			cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_AES192;
> +		else if (keylen == 256)
> +			cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_AES256;
> +		else
> +			return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>  static int nfp_net_xfrm_add_state(struct xfrm_state *x)
>  {
> -	return -EOPNOTSUPP;
> +	int i, key_len, trunc_len, err = 0, saidx = -1;
> +	struct net_device *netdev = x->xso.dev;
> +	struct nfp_net_ipsec_sa_data *sa_data;
> +	struct nfp_ipsec_cfg_add_sa *cfg;
> +	struct nfp_net_ipsec_data *ipd;
> +	struct nfp_ipsec_cfg_mssg msg;

struct nfp_ipsec_cfg_mssg msg = {};

and memset below will be redundant.

> +	struct nfp_net *nn;
> +	__be32 *p;
> +
> +	nn = netdev_priv(netdev);
> +	ipd = nn->ipsec_data;
> +	cfg = &msg.cfg_add_sa;
> +
> +	nn_dbg(nn, "XFRM add state!\n");

ftrace can give it, you don't need add prints for functions entry/exit.

> +	mutex_lock(&ipd->lock);
> +
> +	if (ipd->sa_free_cnt == 0) {
> +		nn_err(nn, "No space for xfrm offload\n");
> +		err = -ENOSPC;

Why don't you return EOPNOTSUPP?

> +		goto error;
> +	}
> +
> +	saidx = ipd->sa_free_stack[ipd->sa_free_cnt - 1];
> +	sa_data = &ipd->sa_entries[saidx];
> +	memset(&msg, 0, sizeof(msg));

Redundant.

> +
> +	/* General */
> +	switch (x->props.mode) {
> +	case XFRM_MODE_TUNNEL:
> +		cfg->ctrl_word.mode = NFP_IPSEC_PROTMODE_TUNNEL;
> +		break;
> +	case XFRM_MODE_TRANSPORT:
> +		cfg->ctrl_word.mode = NFP_IPSEC_PROTMODE_TRANSPORT;
> +		break;
> +	default:
> +		nn_err(nn, "Unsupported mode for xfrm offload\n");
> +		err = -EINVAL;
> +		goto error;
> +	}
> +
> +	switch (x->id.proto) {
> +	case IPPROTO_ESP:
> +		cfg->ctrl_word.proto = NFP_IPSEC_PROTOCOL_ESP;
> +		break;
> +	case IPPROTO_AH:
> +		cfg->ctrl_word.proto = NFP_IPSEC_PROTOCOL_AH;
> +		break;
> +	default:
> +		nn_err(nn, "Unsupported protocol for xfrm offload\n");
> +		err = -EINVAL;
> +		goto error;
> +	}
> +
> +	if (x->props.flags & XFRM_STATE_ESN) {
> +		nn_err(nn, "Unsupported XFRM_REPLAY_MODE_ESN for xfrm offload\n");
> +		err = -EINVAL;
> +		goto error;
> +	}
> +
> +	cfg->ctrl_word.ena_arw = 0;
> +	cfg->ctrl_word.ext_arw = 0;
> +	cfg->spi = ntohl(x->id.spi);
> +
> +	/* Hash/Authentication */
> +	if (x->aalg)
> +		trunc_len = x->aalg->alg_trunc_len;
> +	else
> +		trunc_len = 0;
> +
> +	switch (x->props.aalgo) {
> +	case SADB_AALG_NONE:
> +		if (x->aead) {
> +			trunc_len = -1;
> +		} else {
> +			nn_err(nn, "Unsupported authentication algorithm\n");
> +			err = -EINVAL;
> +			goto error;
> +		}
> +		break;
> +	case SADB_X_AALG_NULL:
> +		cfg->ctrl_word.hash = NFP_IPSEC_HASH_NONE;
> +		trunc_len = -1;
> +		break;
> +	case SADB_AALG_MD5HMAC:
> +		if (trunc_len == 96)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_MD5_96;
> +		else if (trunc_len == 128)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_MD5_128;
> +		else
> +			trunc_len = 0;
> +		break;
> +	case SADB_AALG_SHA1HMAC:
> +		if (trunc_len == 96)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA1_96;
> +		else if (trunc_len == 80)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA1_80;
> +		else
> +			trunc_len = 0;
> +		break;
> +	case SADB_X_AALG_SHA2_256HMAC:
> +		if (trunc_len == 96)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA256_96;
> +		else if (trunc_len == 128)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA256_128;
> +		else
> +			trunc_len = 0;
> +		break;
> +	case SADB_X_AALG_SHA2_384HMAC:
> +		if (trunc_len == 96)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA384_96;
> +		else if (trunc_len == 192)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA384_192;
> +		else
> +			trunc_len = 0;
> +		break;
> +	case SADB_X_AALG_SHA2_512HMAC:
> +		if (trunc_len == 96)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA512_96;
> +		else if (trunc_len == 256)
> +			cfg->ctrl_word.hash = NFP_IPSEC_HASH_SHA512_256;
> +		else
> +			trunc_len = 0;
> +		break;
> +	default:
> +		nn_err(nn, "Unsupported authentication algorithm\n");
> +		err = -EINVAL;
> +		goto error;
> +	}
> +
> +	if (!trunc_len) {
> +		nn_err(nn, "Unsupported authentication algorithm trunc length\n");
> +		err = -EINVAL;
> +		goto error;
> +	}
> +
> +	if (x->aalg) {
> +		p = (__be32 *)x->aalg->alg_key;
> +		key_len = DIV_ROUND_UP(x->aalg->alg_key_len, BITS_PER_BYTE);
> +		if (key_len > sizeof(cfg->auth_key)) {
> +			nn_err(nn, "Insufficient space for offloaded auth key\n");
> +			err = -EINVAL;
> +			goto error;
> +		}
> +		for (i = 0; i < key_len / sizeof(cfg->auth_key[0]) ; i++)
> +			cfg->auth_key[i] = ntohl(*p++);
> +	}
> +	/* Encryption */
> +	switch (x->props.ealgo) {
> +	case SADB_EALG_NONE:
> +	case SADB_EALG_NULL:
> +		cfg->ctrl_word.cimode = NFP_IPSEC_CIMODE_CBC;
> +		cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_NULL;
> +		break;
> +	case SADB_EALG_3DESCBC:
> +		cfg->ctrl_word.cimode = NFP_IPSEC_CIMODE_CBC;
> +		cfg->ctrl_word.cipher = NFP_IPSEC_CIPHER_3DES;
> +		break;
> +	case SADB_X_EALG_AES_GCM_ICV16:
> +	case SADB_X_EALG_NULL_AES_GMAC:
> +		if (!x->aead) {
> +			nn_err(nn, "Invalid AES key data\n");
> +			err = -EINVAL;
> +			goto error;
> +		}
> +
> +		if (x->aead->alg_icv_len != 128) {
> +			nn_err(nn, "ICV must be 128bit with SADB_X_EALG_AES_GCM_ICV16\n");
> +			err = -EINVAL;
> +			goto error;
> +		}
> +		cfg->ctrl_word.cimode = NFP_IPSEC_CIMODE_CTR;
> +		cfg->ctrl_word.hash = NFP_IPSEC_HASH_GF128_128;
> +
> +		/* Aead->alg_key_len includes 32-bit salt */
> +		if (set_aes_keylen(cfg, x->props.ealgo, x->aead->alg_key_len - 32)) {
> +			nn_err(nn, "Unsupported AES key length %d\n", x->aead->alg_key_len);
> +			err = -EINVAL;
> +			goto error;
> +		}
> +		break;
> +	case SADB_X_EALG_AESCBC:
> +		cfg->ctrl_word.cimode = NFP_IPSEC_CIMODE_CBC;
> +		if (!x->ealg) {
> +			nn_err(nn, "Invalid AES key data\n");
> +			err = -EINVAL;
> +			goto error;
> +		}
> +		if (set_aes_keylen(cfg, x->props.ealgo, x->ealg->alg_key_len) < 0) {
> +			nn_err(nn, "Unsupported AES key length %d\n", x->ealg->alg_key_len);
> +			err = -EINVAL;
> +			goto error;
> +		}
> +		break;
> +	default:
> +		nn_err(nn, "Unsupported encryption algorithm for offload\n");
> +		err = -EINVAL;
> +		goto error;
> +	}
> +
> +	if (x->aead) {
> +		int salt_len = 4;
> +
> +		p = (__be32 *)x->aead->alg_key;
> +		key_len = DIV_ROUND_UP(x->aead->alg_key_len, BITS_PER_BYTE);
> +		key_len -= salt_len;
> +
> +		if (key_len > sizeof(cfg->ciph_key)) {
> +			nn_err(nn, "Insufficient space for offloaded key\n");
> +			err = -EINVAL;
> +			goto error;
> +		}
> +
> +		for (i = 0; i < key_len / sizeof(cfg->ciph_key[0]) ; i++)
> +			cfg->ciph_key[i] = ntohl(*p++);
> +
> +		/* Load up the salt */
> +		for (i = 0; i < salt_len; i++)
> +			cfg->auth_key[i] = ntohl(*p++);
> +	}
> +
> +	if (x->ealg) {
> +		p = (__be32 *)x->ealg->alg_key;
> +		key_len = DIV_ROUND_UP(x->ealg->alg_key_len, BITS_PER_BYTE);
> +
> +		if (key_len > sizeof(cfg->ciph_key)) {
> +			nn_err(nn, "Insufficient space for offloaded key\n");
> +			err = -EINVAL;
> +			goto error;
> +		}
> +		for (i = 0; i < key_len / sizeof(cfg->ciph_key[0]) ; i++)
> +			cfg->ciph_key[i] = ntohl(*p++);
> +	}
> +	/* IP related info */
> +	switch (x->props.family) {
> +	case AF_INET:
> +		cfg->ipv6 = 0;
> +		cfg->src_ip[0] = ntohl(x->props.saddr.a4);
> +		cfg->dst_ip[0] = ntohl(x->id.daddr.a4);
> +		break;
> +	case AF_INET6:
> +		cfg->ipv6 = 1;
> +		for (i = 0; i < 4; i++) {
> +			cfg->src_ip[i] = ntohl(x->props.saddr.a6[i]);
> +			cfg->dst_ip[i] = ntohl(x->id.daddr.a6[i]);
> +		}
> +		break;
> +	default:
> +		nn_err(nn, "Unsupported address family\n");
> +		err = -EINVAL;
> +		goto error;
> +	}
> +
> +	/* Maximum nic ipsec code could handle. Other limits may apply. */
> +	cfg->pmtu_limit = 0xffff;
> +
> +	/* Host will generate the sequence numbers so that if packets get
> +	 * fragmented in host, sequence numbers will stay in sync.
> +	 */
> +	cfg->ctrl_word.gen_seq = 0;
> +
> +	cfg->ctrl_word.encap_dsbl = 1;
> +
> +	/* Sa direction */
> +	cfg->ctrl_word.dir = x->xso.dir;
> +
> +	/* Allocate saidx and commit the Sa */
> +	ipd->sa_free_cnt -= 1;
> +	sa_data->invalidated = 0;
> +	sa_data->x = x;
> +	x->xso.offload_handle = saidx + 1;
> +	err = nfp_ipsec_cfg_cmd_issue(nn, NFP_IPSEC_CFG_MSSG_ADD_SA, saidx, &msg);
> +	if (err) {
> +		nn_err(nn, "Failed to issue ipsec command err ret=%d\n", err);
> +		goto error;
> +	}
> +
> +	mutex_unlock(&ipd->lock);
> +
> +	nn_dbg(nn, "Successfully offload saidx %d\n", saidx);
> +	return 0;
> +error:
> +	if (saidx < 0) {
> +		ipd->sa_free_stack[ipd->sa_free_cnt] = saidx;
> +		ipd->sa_free_cnt++;
> +	}
> +	mutex_unlock(&ipd->lock);
> +	x->xso.offload_handle = OFFLOAD_HANDLE_ERROR;

If everything is wired correctly, XFRM core won't never call to driver
with invalid state.

The failure here means that state is not crypto offloaded.

> +	return err;
> +}
> +
> +static void xfrm_invalidate(struct nfp_net *nn, unsigned int saidx, int is_del)
> +{
> +	struct nfp_net_ipsec_data *ipd = nn->ipsec_data;
> +	struct nfp_net_ipsec_sa_data *sa_data;
> +	struct nfp_ipsec_cfg_mssg msg;
> +	int err;
> +
> +	sa_data = &ipd->sa_entries[saidx];
> +	if (!sa_data->invalidated) {
> +		err = nfp_ipsec_cfg_cmd_issue(nn, NFP_IPSEC_CFG_MSSG_INV_SA, saidx, &msg);
> +		if (err)
> +			nn_warn(nn, "Failed to invalidate SA in hardware\n");
> +		sa_data->invalidated = 1;
> +	} else if (is_del) {
> +		nn_warn(nn, "Unexpected invalidate state for offloaded saidx %d\n", saidx);

You definitely need to clean all these not-possible flows.

> +	}
>  }
>  
>  static void nfp_net_xfrm_del_state(struct xfrm_state *x)
>  {
> +	struct net_device *netdev = x->xso.dev;
> +	struct nfp_net_ipsec_data *ipd;
> +	struct nfp_net *nn;
> +
> +	nn = netdev_priv(netdev);
> +	ipd = nn->ipsec_data;
> +
> +	nn_dbg(nn, "XFRM del state!\n");
> +
> +	if (x->xso.offload_handle == OFFLOAD_HANDLE_ERROR) {
> +		nn_err(nn, "Invalid xfrm offload handle\n");
> +		return;
> +	}
> +
> +	mutex_lock(&ipd->lock);
> +	xfrm_invalidate(nn, x->xso.offload_handle - 1, 1);
> +	mutex_unlock(&ipd->lock);
>  }
>  
>  static void nfp_net_xfrm_free_state(struct xfrm_state *x)
>  {
> +	struct net_device *netdev = x->xso.dev;
> +	struct nfp_net_ipsec_data *ipd;
> +	struct nfp_net *nn;
> +	int saidx;
> +
> +	nn = netdev_priv(netdev);
> +	ipd = nn->ipsec_data;
> +
> +	nn_dbg(nn, "XFRM free state!\n");
> +
> +	if (x->xso.offload_handle == OFFLOAD_HANDLE_ERROR) {
> +		nn_err(nn, "Invalid xfrm offload handle\n");
> +		return;
> +	}
> +
> +	mutex_lock(&ipd->lock);
> +	saidx = x->xso.offload_handle - 1;
> +	xfrm_invalidate(nn, saidx, 0);
> +	ipd->sa_entries[saidx].x = NULL;
> +	/* Return saidx to free list */
> +	ipd->sa_free_stack[ipd->sa_free_cnt] = saidx;
> +	ipd->sa_free_cnt++;
> +
> +	mutex_unlock(&ipd->lock);
>  }
>  
>  static bool nfp_net_ipsec_offload_ok(struct sk_buff *skb, struct xfrm_state *x)
>  {
> -	return false;
> +	if (x->props.family == AF_INET) {
> +		/* Offload with IPv4 options is not supported yet */
> +		if (ip_hdr(skb)->ihl != 5)
> +			return false;
> +	} else if (x->props.family == AF_INET6) {
> +		/* Offload with IPv6 extension headers is not support yet */
> +		if (ipv6_ext_hdr(ipv6_hdr(skb)->nexthdr))
> +			return false;
> +	} else {
> +		return false;
> +	}
> +
> +	return true;

This return is unreachable.

>  }
>  
>  static const struct xfrmdev_ops nfp_net_ipsec_xfrmdev_ops = {
> diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> index 040c0c2aad80..0e48e2887278 100644
> --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> @@ -2375,6 +2375,12 @@ static void nfp_net_netdev_init(struct nfp_net *nn)
>  	}
>  	if (nn->cap & NFP_NET_CFG_CTRL_RSS_ANY)
>  		netdev->hw_features |= NETIF_F_RXHASH;
> +
> +#ifdef CONFIG_NFP_NET_IPSEC
> +	if (nn->cap_w1 & NFP_NET_CFG_CTRL_IPSEC)
> +		netdev->hw_features |= NETIF_F_HW_ESP | NETIF_F_HW_ESP_TX_CSUM;
> +#endif
> +
>  	if (nn->cap & NFP_NET_CFG_CTRL_VXLAN) {
>  		if (nn->cap & NFP_NET_CFG_CTRL_LSO) {
>  			netdev->hw_features |= NETIF_F_GSO_UDP_TUNNEL |
> diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
> index fff05496152d..b7e62d1186ca 100644
> --- a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
> +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
> @@ -399,14 +399,14 @@
>   */
>  #define NFP_NET_CFG_MBOX_BASE		0x1800
>  #define NFP_NET_CFG_MBOX_VAL_MAX_SZ	0x1F8
> -
> +#define NFP_NET_CFG_MBOX_VAL		0x1808
>  #define NFP_NET_CFG_MBOX_SIMPLE_CMD	0x0
>  #define NFP_NET_CFG_MBOX_SIMPLE_RET	0x4
>  #define NFP_NET_CFG_MBOX_SIMPLE_VAL	0x8
>  
>  #define NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_ADD 1
>  #define NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_KILL 2
> -
> +#define NFP_NET_CFG_MBOX_CMD_IPSEC 3
>  #define NFP_NET_CFG_MBOX_CMD_PCI_DSCP_PRIOMAP_SET	5
>  #define NFP_NET_CFG_MBOX_CMD_TLV_CMSG			6
>  
> -- 
> 2.30.2
>