net/ncsi/ncsi-rsp.c

Source file repositories/reference/linux-study-clean/net/ncsi/ncsi-rsp.c

File Facts

System
Linux kernel
Corpus path
net/ncsi/ncsi-rsp.c
Extension
.c
Size
34787 bytes
Lines
1273
Domain
Networking Core
Bucket
Sockets, Protocols, Packet Path, And Network Policy
Inferred role
Networking Core: implementation source
Status
source 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

ntohs(h->reason) != NCSI_PKT_RSP_R_NO_ERROR) {
		netdev_dbg(nr->ndp->ndev.dev,
			   "NCSI: non zero response/reason code %04xh, %04xh\n",
			    ntohs(h->code), ntohs(h->reason));
		return -EPERM;
	}

	/* Validate checksum, which might be zeroes if the
	 * sender doesn't support checksum according to NCSI
	 * specification.
	 */
	pchecksum = (__be32 *)((void *)(h + 1) + ALIGN(payload, 4) - 4);
	if (ntohl(*pchecksum) == 0)
		return 0;

	checksum = ncsi_calculate_checksum((unsigned char *)h,
					   sizeof(*h) + payload - 4);

	if (*pchecksum != htonl(checksum)) {
		netdev_dbg(nr->ndp->ndev.dev,
			   "NCSI: checksum mismatched; recd: %08x calc: %08x\n",
			   *pchecksum, htonl(checksum));
		return -EINVAL;
	}

	return 0;
}

static int ncsi_rsp_handler_cis(struct ncsi_request *nr)
{
	struct ncsi_rsp_pkt *rsp;
	struct ncsi_dev_priv *ndp = nr->ndp;
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	unsigned char id;

	rsp = (struct ncsi_rsp_pkt *)skb_network_header(nr->rsp);
	ncsi_find_package_and_channel(ndp, rsp->rsp.common.channel, &np, &nc);
	if (!nc) {
		if (ndp->flags & NCSI_DEV_PROBED)
			return -ENXIO;

		id = NCSI_CHANNEL_INDEX(rsp->rsp.common.channel);
		nc = ncsi_add_channel(np, id);
	}

	return nc ? 0 : -ENODEV;
}

static int ncsi_rsp_handler_sp(struct ncsi_request *nr)
{
	struct ncsi_rsp_pkt *rsp;
	struct ncsi_dev_priv *ndp = nr->ndp;
	struct ncsi_package *np;
	unsigned char id;

	/* Add the package if it's not existing. Otherwise,
	 * to change the state of its child channels.
	 */
	rsp = (struct ncsi_rsp_pkt *)skb_network_header(nr->rsp);
	ncsi_find_package_and_channel(ndp, rsp->rsp.common.channel,
				      &np, NULL);
	if (!np) {
		if (ndp->flags & NCSI_DEV_PROBED)
			return -ENXIO;

		id = NCSI_PACKAGE_INDEX(rsp->rsp.common.channel);
		np = ncsi_add_package(ndp, id);
		if (!np)
			return -ENODEV;
	}

	return 0;
}

static int ncsi_rsp_handler_dp(struct ncsi_request *nr)
{
	struct ncsi_rsp_pkt *rsp;
	struct ncsi_dev_priv *ndp = nr->ndp;
	struct ncsi_package *np;
	struct ncsi_channel *nc;
	unsigned long flags;

	/* Find the package */
	rsp = (struct ncsi_rsp_pkt *)skb_network_header(nr->rsp);
	ncsi_find_package_and_channel(ndp, rsp->rsp.common.channel,
				      &np, NULL);
	if (!np)
		return -ENODEV;

Annotation

Implementation Notes