Subject: Re: [PATCH ipsec-next v13 1/4] xfrm: Add Direction to the SA in or out

From: Sabrina Dubroca <[email-masked]>
Date: Mon, 29 Apr 2024 14:11:32 +0200

2024-04-26, 10:05:06 +0200, Antony Antony wrote:
> diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
> index 810b520493f3..65948598be0b 100644
> --- a/net/xfrm/xfrm_user.c
> +++ b/net/xfrm/xfrm_user.c
> @@ -358,6 +383,64 @@ static int verify_newsa_info(struct xfrm_usersa_info *p,
>  			err = -EINVAL;
>  			goto out;
>  		}
> +
> +		if (sa_dir == XFRM_SA_DIR_OUT) {
> +			NL_SET_ERR_MSG(extack,
> +				       "MTIMER_THRESH attribute should not be set on output SA");
> +			err = -EINVAL;
> +			goto out;
> +		}
> +	}
> +
> +	if (sa_dir == XFRM_SA_DIR_OUT) {
> +		if (p->flags & XFRM_STATE_DECAP_DSCP) {
> +			NL_SET_ERR_MSG(extack, "Flag DECAP_DSCP should not be set for output SA");
> +			err = -EINVAL;
> +			goto out;
> +		}
> +
> +		if (p->flags & XFRM_STATE_ICMP) {
> +			NL_SET_ERR_MSG(extack, "Flag ICMP should not be set for output SA");
> +			err = -EINVAL;
> +			goto out;
> +		}

Maybe also XFRM_STATE_WILDRECV? It looks pretty "input" to me.

> +
> +		if (p->replay_window) {
> +			NL_SET_ERR_MSG(extack, "Replay window should be 0 for output SA");
> +			err = -EINVAL;
> +			goto out;
> +		}
> +
> +		if (attrs[XFRMA_REPLAY_VAL]) {
> +			struct xfrm_replay_state *replay;
> +
> +			replay = nla_data(attrs[XFRMA_REPLAY_VAL]);
> +
> +			if (replay->seq || replay->bitmap) {
> +				NL_SET_ERR_MSG(extack,
> +					       "Replay seq and bitmap should be 0 for output SA");
> +				err = -EINVAL;
> +				goto out;
> +			}
> +		}
> +	}
> +
> +	if (sa_dir == XFRM_SA_DIR_IN) {
> +		if (p->flags & XFRM_STATE_NOPMTUDISC) {
> +			NL_SET_ERR_MSG(extack, "Flag NOPMTUDISC should not be set for input SA");
> +			err = -EINVAL;
> +			goto out;
> +		}
> +
> +		if (attrs[XFRMA_SA_EXTRA_FLAGS]) {
> +			u32 xflags = nla_get_u32(attrs[XFRMA_SA_EXTRA_FLAGS]);
> +
> +			if (xflags & XFRM_SA_XFLAG_DONT_ENCAP_DSCP) {

Shouldn't XFRM_SA_XFLAG_OSEQ_MAY_WRAP also be excluded on input?

Sorry I didn't check all the remaining flags until now.

Apart from that, the series looks good now, so I can also ack it and
add those two extra flags as a follow-up patch. Steffen/Antony, let me
know what you prefer.

Thanks.

-- 
Sabrina