Re: [PATCH net-next v1 04/10] net/mlx5e: Prepare IPsec packet reformat code for tunnel mode

["Samudrala, Sridhar" <sridhar.samudrala@intel.com>]

On 4/13/2023 7:29 AM, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@nvidia.com>
> 
> Refactor setup_pkt_reformat() function to accommodate future extension
> to support tunnel mode.
> 
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
> ---
>   .../mellanox/mlx5/core/en_accel/ipsec.c       |  1 +
>   .../mellanox/mlx5/core/en_accel/ipsec.h       |  2 +-
>   .../mellanox/mlx5/core/en_accel/ipsec_fs.c    | 81 ++++++++++++++-----
>   3 files changed, 63 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c
> index def01bfde610..359da277c03a 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.c
> @@ -297,6 +297,7 @@ void mlx5e_ipsec_build_accel_xfrm_attrs(struct mlx5e_ipsec_sa_entry *sa_entry,
>   	attrs->upspec.sport = ntohs(x->sel.sport);
>   	attrs->upspec.sport_mask = ntohs(x->sel.sport_mask);
>   	attrs->upspec.proto = x->sel.proto;
> +	attrs->mode = x->props.mode;
>   
>   	mlx5e_ipsec_init_limits(sa_entry, attrs);
>   }
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.h b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.h
> index bb89e18b17b4..ae525420a492 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec.h
> @@ -77,7 +77,7 @@ struct mlx5_replay_esn {
>   
>   struct mlx5_accel_esp_xfrm_attrs {
>   	u32   spi;
> -	u32   flags;
> +	u32   mode;
>   	struct aes_gcm_keymat aes_gcm;
>   
>   	union {
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_fs.c b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_fs.c
> index 060be020ca64..6a1ed4114054 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_fs.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_fs.c
> @@ -10,6 +10,7 @@
>   #include "lib/fs_chains.h"
>   
>   #define NUM_IPSEC_FTE BIT(15)
> +#define MLX5_REFORMAT_TYPE_ADD_ESP_TRANSPORT_SIZE 16
>   
>   struct mlx5e_ipsec_fc {
>   	struct mlx5_fc *cnt;
> @@ -836,40 +837,80 @@ static int setup_modify_header(struct mlx5_core_dev *mdev, u32 val, u8 dir,
>   	return 0;
>   }
>   
> +static int
> +setup_pkt_transport_reformat(struct mlx5_accel_esp_xfrm_attrs *attrs,
> +			     struct mlx5_pkt_reformat_params *reformat_params)
> +{
> +	u8 *reformatbf;
> +	__be32 spi;
> +
> +	switch (attrs->dir) {
> +	case XFRM_DEV_OFFLOAD_IN:
> +		reformat_params->type = MLX5_REFORMAT_TYPE_DEL_ESP_TRANSPORT;
> +		break;
> +	case XFRM_DEV_OFFLOAD_OUT:
> +		if (attrs->family == AF_INET)
> +			reformat_params->type =
> +				MLX5_REFORMAT_TYPE_ADD_ESP_TRANSPORT_OVER_IPV4;
> +		else
> +			reformat_params->type =
> +				MLX5_REFORMAT_TYPE_ADD_ESP_TRANSPORT_OVER_IPV6;

Is it guaranteed that attrs->family will be either AF_INET or AF_INET6?
Later patches seem to indicate that this may not be true as they use
switch statement and includes default case


> +
> +		reformatbf = kzalloc(MLX5_REFORMAT_TYPE_ADD_ESP_TRANSPORT_SIZE,
> +				     GFP_KERNEL);
> +		if (!reformatbf)
> +			return -ENOMEM;
> +
> +		/* convert to network format */
> +		spi = htonl(attrs->spi);
> +		memcpy(reformatbf, &spi, sizeof(spi));
> +
> +		reformat_params->param_0 = attrs->authsize;
> +		reformat_params->size =
> +			MLX5_REFORMAT_TYPE_ADD_ESP_TRANSPORT_SIZE;
> +		reformat_params->data = reformatbf;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>   static int setup_pkt_reformat(struct mlx5_core_dev *mdev,
>   			      struct mlx5_accel_esp_xfrm_attrs *attrs,
>   			      struct mlx5_flow_act *flow_act)
>   {
> -	enum mlx5_flow_namespace_type ns_type = MLX5_FLOW_NAMESPACE_EGRESS;
>   	struct mlx5_pkt_reformat_params reformat_params = {};
>   	struct mlx5_pkt_reformat *pkt_reformat;
> -	u8 reformatbf[16] = {};
> -	__be32 spi;
> +	enum mlx5_flow_namespace_type ns_type;
> +	int ret;
>   
> -	if (attrs->dir == XFRM_DEV_OFFLOAD_IN) {
> -		reformat_params.type = MLX5_REFORMAT_TYPE_DEL_ESP_TRANSPORT;
> +	switch (attrs->dir) {
> +	case XFRM_DEV_OFFLOAD_IN:
>   		ns_type = MLX5_FLOW_NAMESPACE_KERNEL;
> -		goto cmd;
> +		break;
> +	case XFRM_DEV_OFFLOAD_OUT:
> +		ns_type = MLX5_FLOW_NAMESPACE_EGRESS;
> +		break;
> +	default:
> +		return -EINVAL;
>   	}
>   
> -	if (attrs->family == AF_INET)
> -		reformat_params.type =
> -			MLX5_REFORMAT_TYPE_ADD_ESP_TRANSPORT_OVER_IPV4;
> -	else
> -		reformat_params.type =
> -			MLX5_REFORMAT_TYPE_ADD_ESP_TRANSPORT_OVER_IPV6;

same here

> -
> -	/* convert to network format */
> -	spi = htonl(attrs->spi);
> -	memcpy(reformatbf, &spi, 4);
> +	switch (attrs->mode) {
> +	case XFRM_MODE_TRANSPORT:
> +		ret = setup_pkt_transport_reformat(attrs, &reformat_params);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
>   
> -	reformat_params.param_0 = attrs->authsize;
> -	reformat_params.size = sizeof(reformatbf);
> -	reformat_params.data = &reformatbf;
> +	if (ret)
> +		return ret;
>   
> -cmd:
>   	pkt_reformat =
>   		mlx5_packet_reformat_alloc(mdev, &reformat_params, ns_type);
> +	kfree(reformat_params.data);
>   	if (IS_ERR(pkt_reformat))
>   		return PTR_ERR(pkt_reformat);
>