net: ipv6: add support for rpl sr exthdr
This patch adds rpl source routing receive handling. Everything works only if sysconf "rpl_seg_enabled" and source routing is enabled. Mostly the same behaviour as IPv6 segmentation routing. To handle compression and uncompression a rpl.c file is created which contains the necessary functionality. The receive handling will also care about IPv6 encapsulated so far it's specified as possible nexthdr in RFC 6554. Signed-off-by: Alexander Aring <alex.aring@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexander Aring
David S. Miller
parent
f37c605936
commit
8610c7c6e3
|
|
@ -74,6 +74,7 @@ struct ipv6_devconf {
|
|||
__u32 addr_gen_mode;
|
||||
__s32 disable_policy;
|
||||
__s32 ndisc_tclass;
|
||||
__s32 rpl_seg_enabled;
|
||||
|
||||
struct ctl_table_header *sysctl_header;
|
||||
};
|
||||
|
|
|
|||
|
|
@ -0,0 +1,34 @@
|
|||
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
||||
/*
|
||||
* RPL implementation
|
||||
*
|
||||
* Author:
|
||||
* (C) 2020 Alexander Aring <alex.aring@gmail.com>
|
||||
*/
|
||||
|
||||
#ifndef _NET_RPL_H
|
||||
#define _NET_RPL_H
|
||||
|
||||
#include <linux/rpl.h>
|
||||
|
||||
/* Worst decompression memory usage ipv6 address (16) + pad 7 */
|
||||
#define IPV6_RPL_SRH_WORST_SWAP_SIZE (sizeof(struct in6_addr) + 7)
|
||||
|
||||
static inline size_t ipv6_rpl_srh_alloc_size(unsigned char n)
|
||||
{
|
||||
return sizeof(struct ipv6_rpl_sr_hdr) +
|
||||
((n + 1) * sizeof(struct in6_addr));
|
||||
}
|
||||
|
||||
size_t ipv6_rpl_srh_size(unsigned char n, unsigned char cmpri,
|
||||
unsigned char cmpre);
|
||||
|
||||
void ipv6_rpl_srh_decompress(struct ipv6_rpl_sr_hdr *outhdr,
|
||||
const struct ipv6_rpl_sr_hdr *inhdr,
|
||||
const struct in6_addr *daddr, unsigned char n);
|
||||
|
||||
void ipv6_rpl_srh_compress(struct ipv6_rpl_sr_hdr *outhdr,
|
||||
const struct ipv6_rpl_sr_hdr *inhdr,
|
||||
const struct in6_addr *daddr, unsigned char n);
|
||||
|
||||
#endif /* _NET_RPL_H */
|
||||
|
|
@ -40,6 +40,7 @@ struct in6_ifreq {
|
|||
#define IPV6_SRCRT_STRICT 0x01 /* Deprecated; will be removed */
|
||||
#define IPV6_SRCRT_TYPE_0 0 /* Deprecated; will be removed */
|
||||
#define IPV6_SRCRT_TYPE_2 2 /* IPv6 type 2 Routing Header */
|
||||
#define IPV6_SRCRT_TYPE_3 3 /* RPL Segment Routing with IPv6 */
|
||||
#define IPV6_SRCRT_TYPE_4 4 /* Segment Routing with IPv6 */
|
||||
|
||||
/*
|
||||
|
|
@ -187,6 +188,7 @@ enum {
|
|||
DEVCONF_DISABLE_POLICY,
|
||||
DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN,
|
||||
DEVCONF_NDISC_TCLASS,
|
||||
DEVCONF_RPL_SEG_ENABLED,
|
||||
DEVCONF_MAX
|
||||
};
|
||||
|
||||
|
|
|
|||
|
|
@ -10,7 +10,7 @@ ipv6-objs := af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o \
|
|||
route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o udplite.o \
|
||||
raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o ping.o \
|
||||
exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o \
|
||||
udp_offload.o seg6.o fib6_notifier.o
|
||||
udp_offload.o seg6.o fib6_notifier.o rpl.o
|
||||
|
||||
ipv6-offload := ip6_offload.o tcpv6_offload.o exthdrs_offload.o
|
||||
|
||||
|
|
|
|||
|
|
@ -236,6 +236,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
|
|||
.enhanced_dad = 1,
|
||||
.addr_gen_mode = IN6_ADDR_GEN_MODE_EUI64,
|
||||
.disable_policy = 0,
|
||||
.rpl_seg_enabled = 0,
|
||||
};
|
||||
|
||||
static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
|
||||
|
|
@ -290,6 +291,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
|
|||
.enhanced_dad = 1,
|
||||
.addr_gen_mode = IN6_ADDR_GEN_MODE_EUI64,
|
||||
.disable_policy = 0,
|
||||
.rpl_seg_enabled = 0,
|
||||
};
|
||||
|
||||
/* Check if link is ready: is it up and is a valid qdisc available */
|
||||
|
|
@ -5520,6 +5522,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
|
|||
array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
|
||||
array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
|
||||
array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
|
||||
array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
|
||||
}
|
||||
|
||||
static inline size_t inet6_ifla6_size(void)
|
||||
|
|
@ -6900,6 +6903,13 @@ static const struct ctl_table addrconf_sysctl[] = {
|
|||
.extra1 = (void *)SYSCTL_ZERO,
|
||||
.extra2 = (void *)&two_five_five,
|
||||
},
|
||||
{
|
||||
.procname = "rpl_seg_enabled",
|
||||
.data = &ipv6_devconf.rpl_seg_enabled,
|
||||
.maxlen = sizeof(int),
|
||||
.mode = 0644,
|
||||
.proc_handler = proc_dointvec,
|
||||
},
|
||||
{
|
||||
/* sentinel */
|
||||
}
|
||||
|
|
|
|||
|
|
@ -48,6 +48,7 @@
|
|||
#ifdef CONFIG_IPV6_SEG6_HMAC
|
||||
#include <net/seg6_hmac.h>
|
||||
#endif
|
||||
#include <net/rpl.h>
|
||||
|
||||
#include <linux/uaccess.h>
|
||||
|
||||
|
|
@ -468,6 +469,195 @@ looped_back:
|
|||
return -1;
|
||||
}
|
||||
|
||||
static int ipv6_rpl_srh_rcv(struct sk_buff *skb)
|
||||
{
|
||||
struct ipv6_rpl_sr_hdr *hdr, *ohdr, *chdr;
|
||||
struct inet6_skb_parm *opt = IP6CB(skb);
|
||||
struct net *net = dev_net(skb->dev);
|
||||
struct inet6_dev *idev;
|
||||
struct ipv6hdr *oldhdr;
|
||||
struct in6_addr addr;
|
||||
unsigned char *buf;
|
||||
int accept_rpl_seg;
|
||||
int i, err;
|
||||
u64 n = 0;
|
||||
u32 r;
|
||||
|
||||
idev = __in6_dev_get(skb->dev);
|
||||
|
||||
accept_rpl_seg = net->ipv6.devconf_all->rpl_seg_enabled;
|
||||
if (accept_rpl_seg > idev->cnf.rpl_seg_enabled)
|
||||
accept_rpl_seg = idev->cnf.rpl_seg_enabled;
|
||||
|
||||
if (!accept_rpl_seg) {
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
|
||||
looped_back:
|
||||
hdr = (struct ipv6_rpl_sr_hdr *)skb_transport_header(skb);
|
||||
|
||||
if (hdr->segments_left == 0) {
|
||||
if (hdr->nexthdr == NEXTHDR_IPV6) {
|
||||
int offset = (hdr->hdrlen + 1) << 3;
|
||||
|
||||
skb_postpull_rcsum(skb, skb_network_header(skb),
|
||||
skb_network_header_len(skb));
|
||||
|
||||
if (!pskb_pull(skb, offset)) {
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
skb_postpull_rcsum(skb, skb_transport_header(skb),
|
||||
offset);
|
||||
|
||||
skb_reset_network_header(skb);
|
||||
skb_reset_transport_header(skb);
|
||||
skb->encapsulation = 0;
|
||||
|
||||
__skb_tunnel_rx(skb, skb->dev, net);
|
||||
|
||||
netif_rx(skb);
|
||||
return -1;
|
||||
}
|
||||
|
||||
opt->srcrt = skb_network_header_len(skb);
|
||||
opt->lastopt = opt->srcrt;
|
||||
skb->transport_header += (hdr->hdrlen + 1) << 3;
|
||||
opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (!pskb_may_pull(skb, sizeof(*hdr))) {
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
|
||||
n = (hdr->hdrlen << 3) - hdr->pad - (16 - hdr->cmpre);
|
||||
r = do_div(n, (16 - hdr->cmpri));
|
||||
/* checks if calculation was without remainder and n fits into
|
||||
* unsigned char which is segments_left field. Should not be
|
||||
* higher than that.
|
||||
*/
|
||||
if (r || (n + 1) > 255) {
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (hdr->segments_left > n + 1) {
|
||||
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
||||
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
|
||||
((&hdr->segments_left) -
|
||||
skb_network_header(skb)));
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (skb_cloned(skb)) {
|
||||
if (pskb_expand_head(skb, IPV6_RPL_SRH_WORST_SWAP_SIZE, 0,
|
||||
GFP_ATOMIC)) {
|
||||
__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
|
||||
IPSTATS_MIB_OUTDISCARDS);
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
} else {
|
||||
err = skb_cow_head(skb, IPV6_RPL_SRH_WORST_SWAP_SIZE);
|
||||
if (unlikely(err)) {
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
}
|
||||
|
||||
hdr = (struct ipv6_rpl_sr_hdr *)skb_transport_header(skb);
|
||||
|
||||
if (!pskb_may_pull(skb, ipv6_rpl_srh_size(n, hdr->cmpri,
|
||||
hdr->cmpre))) {
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
|
||||
hdr->segments_left--;
|
||||
i = n - hdr->segments_left;
|
||||
|
||||
buf = kzalloc(ipv6_rpl_srh_alloc_size(n + 1) * 2, GFP_ATOMIC);
|
||||
if (unlikely(!buf)) {
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
|
||||
ohdr = (struct ipv6_rpl_sr_hdr *)buf;
|
||||
ipv6_rpl_srh_decompress(ohdr, hdr, &ipv6_hdr(skb)->daddr, n);
|
||||
chdr = (struct ipv6_rpl_sr_hdr *)(buf + ((ohdr->hdrlen + 1) << 3));
|
||||
|
||||
if ((ipv6_addr_type(&ipv6_hdr(skb)->daddr) & IPV6_ADDR_MULTICAST) ||
|
||||
(ipv6_addr_type(&ohdr->rpl_segaddr[i]) & IPV6_ADDR_MULTICAST)) {
|
||||
kfree_skb(skb);
|
||||
kfree(buf);
|
||||
return -1;
|
||||
}
|
||||
|
||||
err = ipv6_chk_rpl_srh_loop(net, ohdr->rpl_segaddr, n + 1);
|
||||
if (err) {
|
||||
icmpv6_send(skb, ICMPV6_PARAMPROB, 0, 0);
|
||||
kfree_skb(skb);
|
||||
kfree(buf);
|
||||
return -1;
|
||||
}
|
||||
|
||||
addr = ipv6_hdr(skb)->daddr;
|
||||
ipv6_hdr(skb)->daddr = ohdr->rpl_segaddr[i];
|
||||
ohdr->rpl_segaddr[i] = addr;
|
||||
|
||||
ipv6_rpl_srh_compress(chdr, ohdr, &ipv6_hdr(skb)->daddr, n);
|
||||
|
||||
oldhdr = ipv6_hdr(skb);
|
||||
|
||||
skb_pull(skb, ((hdr->hdrlen + 1) << 3));
|
||||
skb_postpull_rcsum(skb, oldhdr,
|
||||
sizeof(struct ipv6hdr) + ((hdr->hdrlen + 1) << 3));
|
||||
skb_push(skb, ((chdr->hdrlen + 1) << 3) + sizeof(struct ipv6hdr));
|
||||
skb_reset_network_header(skb);
|
||||
skb_mac_header_rebuild(skb);
|
||||
skb_set_transport_header(skb, sizeof(struct ipv6hdr));
|
||||
|
||||
memmove(ipv6_hdr(skb), oldhdr, sizeof(struct ipv6hdr));
|
||||
memcpy(skb_transport_header(skb), chdr, (chdr->hdrlen + 1) << 3);
|
||||
|
||||
ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
|
||||
skb_postpush_rcsum(skb, ipv6_hdr(skb),
|
||||
sizeof(struct ipv6hdr) + ((chdr->hdrlen + 1) << 3));
|
||||
|
||||
kfree(buf);
|
||||
|
||||
skb_dst_drop(skb);
|
||||
|
||||
ip6_route_input(skb);
|
||||
|
||||
if (skb_dst(skb)->error) {
|
||||
dst_input(skb);
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (skb_dst(skb)->dev->flags & IFF_LOOPBACK) {
|
||||
if (ipv6_hdr(skb)->hop_limit <= 1) {
|
||||
__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);
|
||||
icmpv6_send(skb, ICMPV6_TIME_EXCEED,
|
||||
ICMPV6_EXC_HOPLIMIT, 0);
|
||||
kfree_skb(skb);
|
||||
return -1;
|
||||
}
|
||||
ipv6_hdr(skb)->hop_limit--;
|
||||
|
||||
skb_pull(skb, sizeof(struct ipv6hdr));
|
||||
goto looped_back;
|
||||
}
|
||||
|
||||
dst_input(skb);
|
||||
|
||||
return -1;
|
||||
}
|
||||
|
||||
/********************************
|
||||
Routing header.
|
||||
********************************/
|
||||
|
|
@ -506,9 +696,16 @@ static int ipv6_rthdr_rcv(struct sk_buff *skb)
|
|||
return -1;
|
||||
}
|
||||
|
||||
/* segment routing */
|
||||
if (hdr->type == IPV6_SRCRT_TYPE_4)
|
||||
switch (hdr->type) {
|
||||
case IPV6_SRCRT_TYPE_4:
|
||||
/* segment routing */
|
||||
return ipv6_srh_rcv(skb);
|
||||
case IPV6_SRCRT_TYPE_3:
|
||||
/* rpl segment routing */
|
||||
return ipv6_rpl_srh_rcv(skb);
|
||||
default:
|
||||
break;
|
||||
}
|
||||
|
||||
looped_back:
|
||||
if (hdr->segments_left == 0) {
|
||||
|
|
|
|||
|
|
@ -0,0 +1,123 @@
|
|||
// SPDX-License-Identifier: GPL-2.0-only
|
||||
/**
|
||||
* Authors:
|
||||
* (C) 2020 Alexander Aring <alex.aring@gmail.com>
|
||||
*/
|
||||
|
||||
#include <net/ipv6.h>
|
||||
#include <net/rpl.h>
|
||||
|
||||
#define IPV6_PFXTAIL_LEN(x) (sizeof(struct in6_addr) - (x))
|
||||
|
||||
static void ipv6_rpl_addr_decompress(struct in6_addr *dst,
|
||||
const struct in6_addr *daddr,
|
||||
const void *post, unsigned char pfx)
|
||||
{
|
||||
memcpy(dst, daddr, pfx);
|
||||
memcpy(&dst->s6_addr[pfx], post, IPV6_PFXTAIL_LEN(pfx));
|
||||
}
|
||||
|
||||
static void ipv6_rpl_addr_compress(void *dst, const struct in6_addr *addr,
|
||||
unsigned char pfx)
|
||||
{
|
||||
memcpy(dst, &addr->s6_addr[pfx], IPV6_PFXTAIL_LEN(pfx));
|
||||
}
|
||||
|
||||
static void *ipv6_rpl_segdata_pos(const struct ipv6_rpl_sr_hdr *hdr, int i)
|
||||
{
|
||||
return (void *)&hdr->rpl_segdata[i * IPV6_PFXTAIL_LEN(hdr->cmpri)];
|
||||
}
|
||||
|
||||
size_t ipv6_rpl_srh_size(unsigned char n, unsigned char cmpri,
|
||||
unsigned char cmpre)
|
||||
{
|
||||
return (n * IPV6_PFXTAIL_LEN(cmpri)) + IPV6_PFXTAIL_LEN(cmpre);
|
||||
}
|
||||
|
||||
void ipv6_rpl_srh_decompress(struct ipv6_rpl_sr_hdr *outhdr,
|
||||
const struct ipv6_rpl_sr_hdr *inhdr,
|
||||
const struct in6_addr *daddr, unsigned char n)
|
||||
{
|
||||
int i;
|
||||
|
||||
outhdr->nexthdr = inhdr->nexthdr;
|
||||
outhdr->hdrlen = (((n + 1) * sizeof(struct in6_addr)) >> 3);
|
||||
outhdr->pad = 0;
|
||||
outhdr->type = inhdr->type;
|
||||
outhdr->segments_left = inhdr->segments_left;
|
||||
outhdr->cmpri = 0;
|
||||
outhdr->cmpre = 0;
|
||||
|
||||
for (i = 0; i <= n; i++)
|
||||
ipv6_rpl_addr_decompress(&outhdr->rpl_segaddr[i], daddr,
|
||||
ipv6_rpl_segdata_pos(inhdr, i),
|
||||
inhdr->cmpri);
|
||||
|
||||
ipv6_rpl_addr_decompress(&outhdr->rpl_segaddr[n], daddr,
|
||||
ipv6_rpl_segdata_pos(inhdr, n),
|
||||
inhdr->cmpre);
|
||||
}
|
||||
|
||||
static unsigned char ipv6_rpl_srh_calc_cmpri(const struct ipv6_rpl_sr_hdr *inhdr,
|
||||
const struct in6_addr *daddr,
|
||||
unsigned char n)
|
||||
{
|
||||
unsigned char plen;
|
||||
int i;
|
||||
|
||||
for (plen = 0; plen < sizeof(*daddr); plen++) {
|
||||
for (i = 0; i <= n; i++) {
|
||||
if (daddr->s6_addr[plen] !=
|
||||
inhdr->rpl_segaddr[i].s6_addr[plen])
|
||||
return plen;
|
||||
}
|
||||
}
|
||||
|
||||
return plen;
|
||||
}
|
||||
|
||||
static unsigned char ipv6_rpl_srh_calc_cmpre(const struct in6_addr *daddr,
|
||||
const struct in6_addr *last_segment)
|
||||
{
|
||||
unsigned int plen;
|
||||
|
||||
for (plen = 0; plen < sizeof(*daddr); plen++) {
|
||||
if (daddr->s6_addr[plen] != last_segment->s6_addr[plen])
|
||||
break;
|
||||
}
|
||||
|
||||
return plen;
|
||||
}
|
||||
|
||||
void ipv6_rpl_srh_compress(struct ipv6_rpl_sr_hdr *outhdr,
|
||||
const struct ipv6_rpl_sr_hdr *inhdr,
|
||||
const struct in6_addr *daddr, unsigned char n)
|
||||
{
|
||||
unsigned char cmpri, cmpre;
|
||||
size_t seglen;
|
||||
int i;
|
||||
|
||||
cmpri = ipv6_rpl_srh_calc_cmpri(inhdr, daddr, n);
|
||||
cmpre = ipv6_rpl_srh_calc_cmpre(daddr, &inhdr->rpl_segaddr[n]);
|
||||
|
||||
outhdr->nexthdr = inhdr->nexthdr;
|
||||
seglen = (n * IPV6_PFXTAIL_LEN(cmpri)) + IPV6_PFXTAIL_LEN(cmpre);
|
||||
outhdr->hdrlen = seglen >> 3;
|
||||
if (seglen & 0x7) {
|
||||
outhdr->hdrlen++;
|
||||
outhdr->pad = 8 - (seglen & 0x7);
|
||||
} else {
|
||||
outhdr->pad = 0;
|
||||
}
|
||||
outhdr->type = inhdr->type;
|
||||
outhdr->segments_left = inhdr->segments_left;
|
||||
outhdr->cmpri = cmpri;
|
||||
outhdr->cmpre = cmpre;
|
||||
|
||||
for (i = 0; i <= n; i++)
|
||||
ipv6_rpl_addr_compress(ipv6_rpl_segdata_pos(outhdr, i),
|
||||
&inhdr->rpl_segaddr[i], cmpri);
|
||||
|
||||
ipv6_rpl_addr_compress(ipv6_rpl_segdata_pos(outhdr, n),
|
||||
&inhdr->rpl_segaddr[n], cmpre);
|
||||
}
|
||||
Loading…
Reference in New Issue