net/xfrm/xfrm_replay.c

Source file repositories/reference/linux-study-clean/net/xfrm/xfrm_replay.c

File Facts

System
Linux kernel
Corpus path
net/xfrm/xfrm_replay.c
Extension
.c
Size
19243 bytes
Lines
800
Domain
Networking Core
Bucket
Sockets, Protocols, Packet Path, And Network Policy
Inferred role
Networking Core: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

Dependency Surface

Detected Declarations

Annotated Snippet

sizeof(struct xfrm_replay_state)) == 0) {
			x->xflags |= XFRM_TIME_DEFER;
			return;
		}

		break;
	}

	memcpy(&x->preplay, &x->replay, sizeof(struct xfrm_replay_state));
	c.event = XFRM_MSG_NEWAE;
	c.data.aevent = event;
	km_state_notify(x, &c);

	if (x->replay_maxage &&
	    !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
		x->xflags &= ~XFRM_TIME_DEFER;
}

static int __xfrm_replay_overflow(struct xfrm_state *x, struct sk_buff *skb)
{
	int err = 0;
	struct net *net = xs_net(x);

	if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
		XFRM_SKB_CB(skb)->seq.output.low = ++x->replay.oseq;
		XFRM_SKB_CB(skb)->seq.output.hi = 0;
		if (unlikely(x->replay.oseq == 0) &&
		    !(x->props.extra_flags & XFRM_SA_XFLAG_OSEQ_MAY_WRAP)) {
			x->replay.oseq--;
			xfrm_audit_state_replay_overflow(x, skb);
			err = -EOVERFLOW;

			return err;
		}
		if (xfrm_aevent_is_on(net))
			xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
	}

	return err;
}

static int xfrm_replay_check_legacy(struct xfrm_state *x,
				    struct sk_buff *skb, __be32 net_seq)
{
	u32 diff;
	u32 seq = ntohl(net_seq);

	if (!x->props.replay_window)
		return 0;

	if (unlikely(seq == 0))
		goto err;

	if (likely(seq > x->replay.seq))
		return 0;

	diff = x->replay.seq - seq;
	if (diff >= x->props.replay_window) {
		x->stats.replay_window++;
		goto err;
	}

	if (x->replay.bitmap & (1U << diff)) {
		x->stats.replay++;
		goto err;
	}
	return 0;

err:
	xfrm_audit_state_replay(x, skb, net_seq);
	return -EINVAL;
}

static void xfrm_replay_advance_bmp(struct xfrm_state *x, __be32 net_seq);
static void xfrm_replay_advance_esn(struct xfrm_state *x, __be32 net_seq);

void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
{
	u32 diff, seq;

	switch (x->repl_mode) {
	case XFRM_REPLAY_MODE_LEGACY:
		break;
	case XFRM_REPLAY_MODE_BMP:
		return xfrm_replay_advance_bmp(x, net_seq);
	case XFRM_REPLAY_MODE_ESN:
		return xfrm_replay_advance_esn(x, net_seq);
	}

	if (!x->props.replay_window)

Annotation

Implementation Notes