mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 03:10:12 +00:00
![Justin Iurman](/assets/img/avatar_default.png)
Add support for the IOAM inline insertion (only for the host-to-host use case) which is per-route configured with lightweight tunnels. The target is iproute2 and the patch is ready. It will be posted as soon as this patchset is merged. Here is an overview: $ ip -6 ro ad fc00::1/128 encap ioam6 trace type 0x800000 ns 1 size 12 dev eth0 This example configures an IOAM Pre-allocated Trace option attached to the fc00::1/128 prefix. The IOAM namespace (ns) is 1, the size of the pre-allocated trace data block is 12 octets (size) and only the first IOAM data (bit 0: hop_limit + node id) is included in the trace (type) represented as a bitfield. The reason why the in-transit (IPv6-in-IPv6 encapsulation) use case is not implemented is explained on the patchset cover. Signed-off-by: Justin Iurman <justin.iurman@uliege.be> Signed-off-by: David S. Miller <davem@davemloft.net>
274 lines
6.5 KiB
C
274 lines
6.5 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* IPv6 IOAM Lightweight Tunnel implementation
|
|
*
|
|
* Author:
|
|
* Justin Iurman <justin.iurman@uliege.be>
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/net.h>
|
|
#include <linux/netlink.h>
|
|
#include <linux/in6.h>
|
|
#include <linux/ioam6.h>
|
|
#include <linux/ioam6_iptunnel.h>
|
|
#include <net/dst.h>
|
|
#include <net/sock.h>
|
|
#include <net/lwtunnel.h>
|
|
#include <net/ioam6.h>
|
|
|
|
#define IOAM6_MASK_SHORT_FIELDS 0xff100000
|
|
#define IOAM6_MASK_WIDE_FIELDS 0xe00000
|
|
|
|
struct ioam6_lwt_encap {
|
|
struct ipv6_hopopt_hdr eh;
|
|
u8 pad[2]; /* 2-octet padding for 4n-alignment */
|
|
struct ioam6_hdr ioamh;
|
|
struct ioam6_trace_hdr traceh;
|
|
} __packed;
|
|
|
|
struct ioam6_lwt {
|
|
struct ioam6_lwt_encap tuninfo;
|
|
};
|
|
|
|
static struct ioam6_lwt *ioam6_lwt_state(struct lwtunnel_state *lwt)
|
|
{
|
|
return (struct ioam6_lwt *)lwt->data;
|
|
}
|
|
|
|
static struct ioam6_lwt_encap *ioam6_lwt_info(struct lwtunnel_state *lwt)
|
|
{
|
|
return &ioam6_lwt_state(lwt)->tuninfo;
|
|
}
|
|
|
|
static struct ioam6_trace_hdr *ioam6_trace(struct lwtunnel_state *lwt)
|
|
{
|
|
return &(ioam6_lwt_state(lwt)->tuninfo.traceh);
|
|
}
|
|
|
|
static const struct nla_policy ioam6_iptunnel_policy[IOAM6_IPTUNNEL_MAX + 1] = {
|
|
[IOAM6_IPTUNNEL_TRACE] = NLA_POLICY_EXACT_LEN(sizeof(struct ioam6_trace_hdr)),
|
|
};
|
|
|
|
static int nla_put_ioam6_trace(struct sk_buff *skb, int attrtype,
|
|
struct ioam6_trace_hdr *trace)
|
|
{
|
|
struct ioam6_trace_hdr *data;
|
|
struct nlattr *nla;
|
|
int len;
|
|
|
|
len = sizeof(*trace);
|
|
|
|
nla = nla_reserve(skb, attrtype, len);
|
|
if (!nla)
|
|
return -EMSGSIZE;
|
|
|
|
data = nla_data(nla);
|
|
memcpy(data, trace, len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool ioam6_validate_trace_hdr(struct ioam6_trace_hdr *trace)
|
|
{
|
|
u32 fields;
|
|
|
|
if (!trace->type_be32 || !trace->remlen ||
|
|
trace->remlen > IOAM6_TRACE_DATA_SIZE_MAX / 4)
|
|
return false;
|
|
|
|
trace->nodelen = 0;
|
|
fields = be32_to_cpu(trace->type_be32);
|
|
|
|
trace->nodelen += hweight32(fields & IOAM6_MASK_SHORT_FIELDS)
|
|
* (sizeof(__be32) / 4);
|
|
trace->nodelen += hweight32(fields & IOAM6_MASK_WIDE_FIELDS)
|
|
* (sizeof(__be64) / 4);
|
|
|
|
return true;
|
|
}
|
|
|
|
static int ioam6_build_state(struct net *net, struct nlattr *nla,
|
|
unsigned int family, const void *cfg,
|
|
struct lwtunnel_state **ts,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct nlattr *tb[IOAM6_IPTUNNEL_MAX + 1];
|
|
struct ioam6_lwt_encap *tuninfo;
|
|
struct ioam6_trace_hdr *trace;
|
|
struct lwtunnel_state *s;
|
|
int len_aligned;
|
|
int len, err;
|
|
|
|
if (family != AF_INET6)
|
|
return -EINVAL;
|
|
|
|
err = nla_parse_nested(tb, IOAM6_IPTUNNEL_MAX, nla,
|
|
ioam6_iptunnel_policy, extack);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (!tb[IOAM6_IPTUNNEL_TRACE]) {
|
|
NL_SET_ERR_MSG(extack, "missing trace");
|
|
return -EINVAL;
|
|
}
|
|
|
|
trace = nla_data(tb[IOAM6_IPTUNNEL_TRACE]);
|
|
if (!ioam6_validate_trace_hdr(trace)) {
|
|
NL_SET_ERR_MSG_ATTR(extack, tb[IOAM6_IPTUNNEL_TRACE],
|
|
"invalid trace validation");
|
|
return -EINVAL;
|
|
}
|
|
|
|
len = sizeof(*tuninfo) + trace->remlen * 4;
|
|
len_aligned = ALIGN(len, 8);
|
|
|
|
s = lwtunnel_state_alloc(len_aligned);
|
|
if (!s)
|
|
return -ENOMEM;
|
|
|
|
tuninfo = ioam6_lwt_info(s);
|
|
tuninfo->eh.hdrlen = (len_aligned >> 3) - 1;
|
|
tuninfo->pad[0] = IPV6_TLV_PADN;
|
|
tuninfo->ioamh.type = IOAM6_TYPE_PREALLOC;
|
|
tuninfo->ioamh.opt_type = IPV6_TLV_IOAM;
|
|
tuninfo->ioamh.opt_len = sizeof(tuninfo->ioamh) - 2 + sizeof(*trace)
|
|
+ trace->remlen * 4;
|
|
|
|
memcpy(&tuninfo->traceh, trace, sizeof(*trace));
|
|
|
|
len = len_aligned - len;
|
|
if (len == 1) {
|
|
tuninfo->traceh.data[trace->remlen * 4] = IPV6_TLV_PAD1;
|
|
} else if (len > 0) {
|
|
tuninfo->traceh.data[trace->remlen * 4] = IPV6_TLV_PADN;
|
|
tuninfo->traceh.data[trace->remlen * 4 + 1] = len - 2;
|
|
}
|
|
|
|
s->type = LWTUNNEL_ENCAP_IOAM6;
|
|
s->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT;
|
|
|
|
*ts = s;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ioam6_do_inline(struct sk_buff *skb, struct ioam6_lwt_encap *tuninfo)
|
|
{
|
|
struct ioam6_trace_hdr *trace;
|
|
struct ipv6hdr *oldhdr, *hdr;
|
|
struct ioam6_namespace *ns;
|
|
int hdrlen, err;
|
|
|
|
hdrlen = (tuninfo->eh.hdrlen + 1) << 3;
|
|
|
|
err = skb_cow_head(skb, hdrlen + skb->mac_len);
|
|
if (unlikely(err))
|
|
return err;
|
|
|
|
oldhdr = ipv6_hdr(skb);
|
|
skb_pull(skb, sizeof(*oldhdr));
|
|
skb_postpull_rcsum(skb, skb_network_header(skb), sizeof(*oldhdr));
|
|
|
|
skb_push(skb, sizeof(*oldhdr) + hdrlen);
|
|
skb_reset_network_header(skb);
|
|
skb_mac_header_rebuild(skb);
|
|
|
|
hdr = ipv6_hdr(skb);
|
|
memmove(hdr, oldhdr, sizeof(*oldhdr));
|
|
tuninfo->eh.nexthdr = hdr->nexthdr;
|
|
|
|
skb_set_transport_header(skb, sizeof(*hdr));
|
|
skb_postpush_rcsum(skb, hdr, sizeof(*hdr) + hdrlen);
|
|
|
|
memcpy(skb_transport_header(skb), (u8 *)tuninfo, hdrlen);
|
|
|
|
hdr->nexthdr = NEXTHDR_HOP;
|
|
hdr->payload_len = cpu_to_be16(skb->len - sizeof(*hdr));
|
|
|
|
trace = (struct ioam6_trace_hdr *)(skb_transport_header(skb)
|
|
+ sizeof(struct ipv6_hopopt_hdr) + 2
|
|
+ sizeof(struct ioam6_hdr));
|
|
|
|
ns = ioam6_namespace(dev_net(skb_dst(skb)->dev), trace->namespace_id);
|
|
if (ns)
|
|
ioam6_fill_trace_data(skb, ns, trace);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ioam6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct lwtunnel_state *lwt = skb_dst(skb)->lwtstate;
|
|
int err = -EINVAL;
|
|
|
|
if (skb->protocol != htons(ETH_P_IPV6))
|
|
goto drop;
|
|
|
|
/* Only for packets we send and
|
|
* that do not contain a Hop-by-Hop yet
|
|
*/
|
|
if (skb->dev || ipv6_hdr(skb)->nexthdr == NEXTHDR_HOP)
|
|
goto out;
|
|
|
|
err = ioam6_do_inline(skb, ioam6_lwt_info(lwt));
|
|
if (unlikely(err))
|
|
goto drop;
|
|
|
|
err = skb_cow_head(skb, LL_RESERVED_SPACE(skb_dst(skb)->dev));
|
|
if (unlikely(err))
|
|
goto drop;
|
|
|
|
out:
|
|
return lwt->orig_output(net, sk, skb);
|
|
|
|
drop:
|
|
kfree_skb(skb);
|
|
return err;
|
|
}
|
|
|
|
static int ioam6_fill_encap_info(struct sk_buff *skb,
|
|
struct lwtunnel_state *lwtstate)
|
|
{
|
|
struct ioam6_trace_hdr *trace = ioam6_trace(lwtstate);
|
|
|
|
if (nla_put_ioam6_trace(skb, IOAM6_IPTUNNEL_TRACE, trace))
|
|
return -EMSGSIZE;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ioam6_encap_nlsize(struct lwtunnel_state *lwtstate)
|
|
{
|
|
struct ioam6_trace_hdr *trace = ioam6_trace(lwtstate);
|
|
|
|
return nla_total_size(sizeof(*trace));
|
|
}
|
|
|
|
static int ioam6_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
|
|
{
|
|
struct ioam6_trace_hdr *a_hdr = ioam6_trace(a);
|
|
struct ioam6_trace_hdr *b_hdr = ioam6_trace(b);
|
|
|
|
return (a_hdr->namespace_id != b_hdr->namespace_id);
|
|
}
|
|
|
|
static const struct lwtunnel_encap_ops ioam6_iptun_ops = {
|
|
.build_state = ioam6_build_state,
|
|
.output = ioam6_output,
|
|
.fill_encap = ioam6_fill_encap_info,
|
|
.get_encap_size = ioam6_encap_nlsize,
|
|
.cmp_encap = ioam6_encap_cmp,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
int __init ioam6_iptunnel_init(void)
|
|
{
|
|
return lwtunnel_encap_add_ops(&ioam6_iptun_ops, LWTUNNEL_ENCAP_IOAM6);
|
|
}
|
|
|
|
void ioam6_iptunnel_exit(void)
|
|
{
|
|
lwtunnel_encap_del_ops(&ioam6_iptun_ops, LWTUNNEL_ENCAP_IOAM6);
|
|
}
|