/*
 * xfrm6_mode_beet.c - BEET mode encapsulation for IPv6.
 *
 * Copyright (c) 2006 Diego Beltrami <diego.beltrami@gmail.com>
 *                    Miika Komu     <miika@iki.fi>
 *                    Herbert Xu     <herbert@gondor.apana.org.au>
 *                    Abhinav Pathak <abhinav.pathak@hiit.fi>
 *                    Jeff Ahrenholz <ahrenholz@gmail.com>
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/stringify.h>
#include <net/dsfield.h>
#include <net/dst.h>
#include <net/inet_ecn.h>
#include <net/ipv6.h>
#include <net/xfrm.h>

static void xfrm6_beet_make_header(struct sk_buff *skb)
{
	struct ipv6hdr *iph = ipv6_hdr(skb);

	iph->version = 6;

	memcpy(iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl,
	       sizeof(iph->flow_lbl));
	iph->nexthdr = XFRM_MODE_SKB_CB(skb)->protocol;

	ipv6_change_dsfield(iph, 0, XFRM_MODE_SKB_CB(skb)->tos);
	iph->hop_limit = XFRM_MODE_SKB_CB(skb)->ttl;
}

/* Add encapsulation header.
 *
 * The top IP header will be constructed per draft-nikander-esp-beet-mode-06.txt.
 */
static int xfrm6_beet_output(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *top_iph;
	struct ip_beet_phdr *ph;
	int optlen, hdr_len;

	hdr_len = 0;
	optlen = XFRM_MODE_SKB_CB(skb)->optlen;
	if (unlikely(optlen))
		hdr_len += IPV4_BEET_PHMAXLEN - (optlen & 4);

	skb_set_network_header(skb, -x->props.header_len - hdr_len);
	if (x->sel.family != AF_INET6)
		skb->network_header += IPV4_BEET_PHMAXLEN;
	skb->mac_header = skb->network_header +
			  offsetof(struct ipv6hdr, nexthdr);
	skb->transport_header = skb->network_header + sizeof(*top_iph);
	ph = (struct ip_beet_phdr *)__skb_pull(skb, XFRM_MODE_SKB_CB(skb)->ihl-hdr_len);

	xfrm6_beet_make_header(skb);

	top_iph = ipv6_hdr(skb);
	if (unlikely(optlen)) {

		BUG_ON(optlen < 0);

		ph->padlen = 4 - (optlen & 4);
		ph->hdrlen = optlen / 8;
		ph->nexthdr = top_iph->nexthdr;
		if (ph->padlen)
			memset(ph + 1, IPOPT_NOP, ph->padlen);

		top_iph->nexthdr = IPPROTO_BEETPH;
	}

	top_iph->saddr = *(struct in6_addr *)&x->props.saddr;
	top_iph->daddr = *(struct in6_addr *)&x->id.daddr;
	return 0;
}

static int xfrm6_beet_input(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *ip6h;
	int size = sizeof(struct ipv6hdr);
	int err;

	err = skb_cow_head(skb, size + skb->mac_len);
	if (err)
		goto out;

	__skb_push(skb, size);
	skb_reset_network_header(skb);
	skb_mac_header_rebuild(skb);

	xfrm6_beet_make_header(skb);

	ip6h = ipv6_hdr(skb);
	ip6h->payload_len = htons(skb->len - size);
	ip6h->daddr = x->sel.daddr.in6;
	ip6h->saddr = x->sel.saddr.in6;
	err = 0;
out:
	return err;
}

static struct xfrm_mode xfrm6_beet_mode = {
	.input2 = xfrm6_beet_input,
	.input = xfrm_prepare_input,
	.output2 = xfrm6_beet_output,
	.output = xfrm6_prepare_output,
	.owner = THIS_MODULE,
	.encap = XFRM_MODE_BEET,
	.flags = XFRM_MODE_FLAG_TUNNEL,
};

static int __init xfrm6_beet_init(void)
{
	return xfrm_register_mode(&xfrm6_beet_mode, AF_INET6);
}

static void __exit xfrm6_beet_exit(void)
{
	int err;

	err = xfrm_unregister_mode(&xfrm6_beet_mode, AF_INET6);
	BUG_ON(err);
}

module_init(xfrm6_beet_init);
module_exit(xfrm6_beet_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_BEET);
ion><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</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'>2016-12-12 21:58:13 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-12-12 21:58:13 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/input/appletouch.txt?id=e7aa8c2eb11ba69b1b69099c3c7bd6be3087b0ba'>e7aa8c2eb11ba69b1b69099c3c7bd6be3087b0ba</a> (<a href='/cgit.cgi/linux/net-next.git/patch/Documentation/input/appletouch.txt?id=e7aa8c2eb11ba69b1b69099c3c7bd6be3087b0ba'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/'>f63906f41699c8e38af9d12b063e2ceab0286ef2</a> /<a href='/cgit.cgi/linux/net-next.git/tree/Documentation/input/appletouch.txt'>Documentation/input/appletouch.txt</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/input/appletouch.txt?id=e34bac726d27056081d0250c0e173e4b155aa340'>e34bac726d27056081d0250c0e173e4b155aa340</a> (<a href='/cgit.cgi/linux/net-next.git/diff/Documentation/input/appletouch.txt?id2=e34bac726d27056081d0250c0e173e4b155aa340'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/input/appletouch.txt?id=868c97a846a73e937d835b09b8c885a69df50ec8'>868c97a846a73e937d835b09b8c885a69df50ec8</a> (<a href='/cgit.cgi/linux/net-next.git/diff/Documentation/input/appletouch.txt?id2=868c97a846a73e937d835b09b8c885a69df50ec8'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge tag 'docs-4.10' of git://git.lwn.net/linux<span class='decoration'><a class='deco' href='/cgit.cgi/linux/net-next.git/commit/Documentation/input/appletouch.txt?id=e7aa8c2eb11ba69b1b69099c3c7bd6be3087b0ba'>HEAD</a><a class='branch-deco' href='/cgit.cgi/linux/net-next.git/log/Documentation/input/appletouch.txt'>master</a></span></div><div class='commit-msg'>Pull documentation update from Jonathan Corbet:
 "These are the documentation changes for 4.10.

  It's another busy cycle for the docs tree, as the sphinx conversion
  continues. Highlights include:

   - Further work on PDF output, which remains a bit of a pain but
     should be more solid now.

   - Five more DocBook template files converted to Sphinx. Only 27 to
     go... Lots of plain-text files have also been converted and
     integrated.

   - Images in binary formats have been replaced with more
     source-friendly versions.

   - Various bits of organizational work, including the renaming of
     various files discussed at the kernel summit.

   - New documentation for the device_link mechanism.

  ... and, of course, lots of typo fixes and small updates"

* tag 'docs-4.10' of git://git.lwn.net/linux: (193 commits)
  dma-buf: Extract dma-buf.rst
  Update Documentation/00-INDEX
  docs: 00-INDEX: document directories/files with no docs
  docs: 00-INDEX: remove non-existing entries
  docs: 00-INDEX: add missing entries for documentation files/dirs
  docs: 00-INDEX: consolidate process/ and admin-guide/ description
  scripts: add a script to check if Documentation/00-INDEX is sane
  Docs: change sh -&gt; awk in REPORTING-BUGS
  Documentation/core-api/device_link: Add initial documentation
  core-api: remove an unexpected unident
  ppc/idle: Add documentation for powersave=off
  Doc: Correct typo, "Introdution" =&gt; "Introduction"
  Documentation/atomic_ops.txt: convert to ReST markup
  Documentation/local_ops.txt: convert to ReST markup
  Documentation/assoc_array.txt: convert to ReST markup
  docs-rst: parse-headers.pl: cleanup the documentation
  docs-rst: fix media cleandocs target
  docs-rst: media/Makefile: reorganize the rules
  docs-rst: media: build SVG from graphviz files
  docs-rst: replace bayer.png by a SVG image
  ...
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/'>Diffstat</a> (limited to 'Documentation/input/appletouch.txt')</div><table summary='diffstat' class='diffstat'>