/*
 * net/ife/ife.c - Inter-FE protocol based on ForCES WG InterFE LFB
 * Copyright (c) 2015 Jamal Hadi Salim <jhs@mojatatu.com>
 * Copyright (c) 2017 Yotam Gigi <yotamg@mellanox.com>
 *
 * Refer to: draft-ietf-forces-interfelfb-03 and netdev01 paper:
 * "Distributing Linux Traffic Control Classifier-Action Subsystem"
 * Authors: Jamal Hadi Salim and Damascene M. Joachimpillai
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation.
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/etherdevice.h>
#include <net/ife.h>

struct ifeheadr {
	__be16 metalen;
	u8 tlv_data[];
};

void *ife_encode(struct sk_buff *skb, u16 metalen)
{
	/* OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA
	 * where ORIGDATA = original ethernet header ...
	 */
	int hdrm = metalen + IFE_METAHDRLEN;
	int total_push = hdrm + skb->dev->hard_header_len;
	struct ifeheadr *ifehdr;
	struct ethhdr *iethh;	/* inner ether header */
	int skboff = 0;
	int err;

	err = skb_cow_head(skb, total_push);
	if (unlikely(err))
		return NULL;

	iethh = (struct ethhdr *) skb->data;

	__skb_push(skb, total_push);
	memcpy(skb->data, iethh, skb->dev->hard_header_len);
	skb_reset_mac_header(skb);
	skboff += skb->dev->hard_header_len;

	/* total metadata length */
	ifehdr = (struct ifeheadr *) (skb->data + skboff);
	metalen += IFE_METAHDRLEN;
	ifehdr->metalen = htons(metalen);

	return ifehdr->tlv_data;
}
EXPORT_SYMBOL_GPL(ife_encode);

void *ife_decode(struct sk_buff *skb, u16 *metalen)
{
	struct ifeheadr *ifehdr;
	int total_pull;
	u16 ifehdrln;

	ifehdr = (struct ifeheadr *) (skb->data + skb->dev->hard_header_len);
	ifehdrln = ntohs(ifehdr->metalen);
	total_pull = skb->dev->hard_header_len + ifehdrln;

	if (unlikely(ifehdrln < 2))
		return NULL;

	if (unlikely(!pskb_may_pull(skb, total_pull)))
		return NULL;

	skb_set_mac_header(skb, total_pull);
	__skb_pull(skb, total_pull);
	*metalen = ifehdrln - IFE_METAHDRLEN;

	return &ifehdr->tlv_data;
}
EXPORT_SYMBOL_GPL(ife_decode);

struct meta_tlvhdr {
	__be16 type;
	__be16 len;
};

/* Caller takes care of presenting data in network order
 */
void *ife_tlv_meta_decode(void *skbdata, u16 *attrtype, u16 *dlen, u16 *totlen)
{
	struct meta_tlvhdr *tlv = (struct meta_tlvhdr *) skbdata;

	*dlen = ntohs(tlv->len) - NLA_HDRLEN;
	*attrtype = ntohs(tlv->type);

	if (totlen)
		*totlen = nla_total_size(*dlen);

	return skbdata + sizeof(struct meta_tlvhdr);
}
EXPORT_SYMBOL_GPL(ife_tlv_meta_decode);

void *ife_tlv_meta_next(void *skbdata)
{
	struct meta_tlvhdr *tlv = (struct meta_tlvhdr *) skbdata;
	u16 tlvlen = ntohs(tlv->len);

	tlvlen = NLA_ALIGN(tlvlen);

	return skbdata + tlvlen;
}
EXPORT_SYMBOL_GPL(ife_tlv_meta_next);

/* Caller takes care of presenting data in network order
 */
int ife_tlv_meta_encode(void *skbdata, u16 attrtype, u16 dlen, const void *dval)
{
	__be32 *tlv = (__be32 *) (skbdata);
	u16 totlen = nla_total_size(dlen);	/*alignment + hdr */
	char *dptr = (char *) tlv + NLA_HDRLEN;
	u32 htlv = attrtype << 16 | (dlen + NLA_HDRLEN);

	*tlv = htonl(htlv);
	memset(dptr, 0, totlen - NLA_HDRLEN);
	memcpy(dptr, dval, dlen);

	return totlen;
}
EXPORT_SYMBOL_GPL(ife_tlv_meta_encode);

MODULE_AUTHOR("Jamal Hadi Salim <jhs@mojatatu.com>");
MODULE_AUTHOR("Yotam Gigi <yotamg@mellanox.com>");
MODULE_DESCRIPTION("Inter-FE LFB action");
MODULE_LICENSE("GPL");
ified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-10-07 11:58:38 -0700</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-10-07 11:58:38 -0700</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=bc75450cc3db3485db1e289fef8c1028ba38296a'>bc75450cc3db3485db1e289fef8c1028ba38296a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=bc75450cc3db3485db1e289fef8c1028ba38296a'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=bc75450cc3db3485db1e289fef8c1028ba38296a'>cd7dca62f9f60524ed5241a9e2fbdce1c8ab0bb7</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=e6e3d8f8f4f06caf25004c749bb2ba84f18c7d39'>e6e3d8f8f4f06caf25004c749bb2ba84f18c7d39</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=bc75450cc3db3485db1e289fef8c1028ba38296a&amp;id2=e6e3d8f8f4f06caf25004c749bb2ba84f18c7d39'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=179023e6af0c608ffb505821223f5580853ef6b8'>179023e6af0c608ffb505821223f5580853ef6b8</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=bc75450cc3db3485db1e289fef8c1028ba38296a&amp;id2=179023e6af0c608ffb505821223f5580853ef6b8'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid</div><div class='commit-msg'>Pull HID updates from Jiri Kosina:

 - Integrated Sensor Hub support (Cherrytrail+) from Srinivas Pandruvada

 - Big cleanup of Wacom driver; namely it's now using devres, and the
   standardized LED API so that libinput doesn't need to have root
   access any more, with substantial amount of other cleanups
   piggy-backing on top. All this from Benjamin Tissoires

 - Report descriptor parsing would now ignore and out-of-range System
   controls in case of the application actually being System Control.
   This fixes quite some issues with several devices, and allows us to
   remove a few -&gt;report_fixup callbacks. From Benjamin Tissoires

 - ... a lot of other assorted small fixes and device ID additions

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (76 commits)
  HID: add missing \n to end of dev_warn messages
  HID: alps: fix multitouch cursor issue
  HID: hid-logitech: Documentation updates/corrections
  HID: hid-logitech: Improve Wingman Formula Force GP support
  HID: hid-logitech: Rewrite of descriptor for all DF wheels
  HID: hid-logitech: Compute combined pedals value
  HID: hid-logitech: Add combined pedal support Logitech wheels
  HID: hid-logitech: Introduce control for combined pedals feature
  HID: sony: Update copyright and add Dualshock 4 rate control note
  HID: sony: Defer the initial USB Sixaxis output report
  HID: sony: Relax duplicate checking for USB-only devices
  Revert "HID: microsoft: fix invalid rdesc for 3k kbd"
  HID: alps: fix error return code in alps_input_configured()
  HID: alps: fix stick device not working after resume
  HID: support for keyboard - Corsair STRAFE
  HID: alps: Fix memory leak
  HID: uclogic: Add support for UC-Logic TWHA60 v3
  HID: uclogic: Override constant descriptors
  HID: uclogic: Support UGTizer GP0610 partially
  HID: uclogic: Add support for several more tablets
  ...
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=bc75450cc3db3485db1e289fef8c1028ba38296a'>Diffstat</a></div><table summary='diffstat' class='diffstat'>