Subject: Re: [net-next,v3 5/8] cn10k-ipsec: Add SA add/delete support for outb inline ipsec

From: Leon Romanovsky <[email-masked]>
Date: Thu, 30 May 2024 17:49:59 +0300

On Tue, May 28, 2024 at 07:23:46PM +0530, Bharat Bhushan wrote:
> This patch adds support to add and delete Security Association
> (SA) xfrm ops. Hardware maintains SA context in memory allocated
> by software. Each SA context is 128 byte aligned and size of
> each context is multiple of 128-byte. Add support for transport
> and tunnel ipsec mode, ESP protocol, aead aes-gcm-icv16, key size
> 128/192/256-bits with 32bit salt.
> 
> Signed-off-by: Bharat Bhushan <[email-masked]>
> ---
> v2->v3:
>  - Removed memset to zero wherever possible
>   (comment from Kalesh Anakkur Purayil)
>  - Corrected error hanlding when setting SA for inbound
>    (comment from Kalesh Anakkur Purayil)
>  - Move "netdev->xfrmdev_ops = &cn10k_ipsec_xfrmdev_ops;" to this patch
>    This fix build error with W=1
> 
>  .../marvell/octeontx2/nic/cn10k_ipsec.c       | 452 ++++++++++++++++++
>  .../marvell/octeontx2/nic/cn10k_ipsec.h       | 114 +++++
>  2 files changed, 566 insertions(+)

<...>

> +static int cn10k_ipsec_validate_state(struct xfrm_state *x)
> +{
> +	struct net_device *netdev = x->xso.dev;
> +
> +	if (x->props.aalgo != SADB_AALG_NONE) {
> +		netdev_err(netdev, "Cannot offload authenticated xfrm states\n");
> +		return -EINVAL;
> +	}
> +	if (x->props.ealgo != SADB_X_EALG_AES_GCM_ICV16) {
> +		netdev_err(netdev, "Only AES-GCM-ICV16 xfrm state may be offloaded\n");
> +		return -EINVAL;
> +	}
> +	if (x->props.calgo != SADB_X_CALG_NONE) {
> +		netdev_err(netdev, "Cannot offload compressed xfrm states\n");
> +		return -EINVAL;
> +	}
> +	if (x->props.flags & XFRM_STATE_ESN) {
> +		netdev_err(netdev, "Cannot offload ESN xfrm states\n");
> +		return -EINVAL;
> +	}

I afraid that this check will cause for this offload to be unusable in
real life scenarios. It is hard to imagine that someone will use offload
which requires rekeying every 2^32 packets.

> +	if (x->props.family != AF_INET && x->props.family != AF_INET6) {
> +		netdev_err(netdev, "Only IPv4/v6 xfrm states may be offloaded\n");
> +		return -EINVAL;
> +	}
> +	if (x->props.mode != XFRM_MODE_TRANSPORT &&
> +	    x->props.mode != XFRM_MODE_TUNNEL) {
> +		dev_info(&netdev->dev, "Only tunnel/transport xfrm states may be offloaded\n");
> +		return -EINVAL;
> +	}
> +	if (x->id.proto != IPPROTO_ESP) {
> +		netdev_err(netdev, "Only ESP xfrm state may be offloaded\n");
> +		return -EINVAL;
> +	}
> +	if (x->encap) {
> +		netdev_err(netdev, "Encapsulated xfrm state may not be offloaded\n");
> +		return -EINVAL;
> +	}
> +	if (!x->aead) {
> +		netdev_err(netdev, "Cannot offload xfrm states without aead\n");
> +		return -EINVAL;
> +	}
> +
> +	if (x->aead->alg_icv_len != 128) {
> +		netdev_err(netdev, "Cannot offload xfrm states with AEAD ICV length other than 128bit\n");
> +		return -EINVAL;
> +	}
> +	if (x->aead->alg_key_len != 128 + 32 &&
> +	    x->aead->alg_key_len != 192 + 32 &&
> +	    x->aead->alg_key_len != 256 + 32) {
> +		netdev_err(netdev, "Cannot offload xfrm states with AEAD key length other than 128/192/256bit\n");
> +		return -EINVAL;
> +	}
> +	if (x->tfcpad) {
> +		netdev_err(netdev, "Cannot offload xfrm states with tfc padding\n");
> +		return -EINVAL;
> +	}
> +	if (!x->geniv) {
> +		netdev_err(netdev, "Cannot offload xfrm states without geniv\n");
> +		return -EINVAL;
> +	}
> +	if (strcmp(x->geniv, "seqiv")) {
> +		netdev_err(netdev, "Cannot offload xfrm states with geniv other than seqiv\n");
> +		return -EINVAL;
> +	}
> +	return 0;
> +}

I don't see check for supported offload type among these checks.
if (x->xso.type != XFRM_DEV_OFFLOAD_CRYPTO) {
 ....