@@ -9,9 +9,38 @@
#ifndef _UAPI_LINUX_IOAM6_IPTUNNEL_H
#define _UAPI_LINUX_IOAM6_IPTUNNEL_H
+/* Encap modes:
+ * - inline: direct insertion
+ * - encap: ip6ip6 encapsulation
+ * - auto: inline for local packets, encap for in-transit packets
+ */
+enum {
+ __IOAM6_IPTUNNEL_MODE_MIN,
+
+ IOAM6_IPTUNNEL_MODE_INLINE,
+ IOAM6_IPTUNNEL_MODE_ENCAP,
+ IOAM6_IPTUNNEL_MODE_AUTO,
+
+ __IOAM6_IPTUNNEL_MODE_MAX,
+};
+
+#define IOAM6_IPTUNNEL_MODE_MIN (__IOAM6_IPTUNNEL_MODE_MIN + 1)
+#define IOAM6_IPTUNNEL_MODE_MAX (__IOAM6_IPTUNNEL_MODE_MAX - 1)
+
enum {
IOAM6_IPTUNNEL_UNSPEC,
+
+ /* Encap mode */
+ IOAM6_IPTUNNEL_MODE, /* u8 */
+
+ /* Tunnel dst address.
+ * For encap,auto modes.
+ */
+ IOAM6_IPTUNNEL_DST, /* struct in6_addr */
+
+ /* IOAM Trace Header */
IOAM6_IPTUNNEL_TRACE, /* struct ioam6_trace_hdr */
+
__IOAM6_IPTUNNEL_MAX,
};
@@ -332,10 +332,10 @@ config IPV6_IOAM6_LWTUNNEL
bool "IPv6: IOAM Pre-allocated Trace insertion support"
depends on IPV6
select LWTUNNEL
+ select DST_CACHE
help
- Support for the inline insertion of IOAM Pre-allocated
- Trace Header (only on locally generated packets), using
- the lightweight tunnels mechanism.
+ Support for the insertion of IOAM Pre-allocated Trace
+ Header using the lightweight tunnels mechanism.
If unsure, say N.
@@ -17,6 +17,10 @@
#include <net/lwtunnel.h>
#include <net/ioam6.h>
#include <net/netlink.h>
+#include <net/ipv6.h>
+#include <net/dst_cache.h>
+#include <net/ip6_route.h>
+#include <net/addrconf.h>
#define IOAM6_MASK_SHORT_FIELDS 0xff100000
#define IOAM6_MASK_WIDE_FIELDS 0xe00000
@@ -29,6 +33,9 @@ struct ioam6_lwt_encap {
} __packed;
struct ioam6_lwt {
+ struct dst_cache cache;
+ u8 mode;
+ struct in6_addr tundst;
struct ioam6_lwt_encap tuninfo;
};
@@ -48,6 +55,10 @@ static struct ioam6_trace_hdr *ioam6_lwt_trace(struct lwtunnel_state *lwt)
}
static const struct nla_policy ioam6_iptunnel_policy[IOAM6_IPTUNNEL_MAX + 1] = {
+ [IOAM6_IPTUNNEL_MODE] = NLA_POLICY_RANGE(NLA_U8,
+ IOAM6_IPTUNNEL_MODE_MIN,
+ IOAM6_IPTUNNEL_MODE_MAX),
+ [IOAM6_IPTUNNEL_DST] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
[IOAM6_IPTUNNEL_TRACE] = NLA_POLICY_EXACT_LEN(sizeof(struct ioam6_trace_hdr)),
};
@@ -78,9 +89,10 @@ static int ioam6_build_state(struct net *net, struct nlattr *nla,
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;
+ struct lwtunnel_state *lwt;
+ struct ioam6_lwt *ilwt;
+ int len_aligned, err;
+ u8 mode;
if (family != AF_INET6)
return -EINVAL;
@@ -90,6 +102,16 @@ static int ioam6_build_state(struct net *net, struct nlattr *nla,
if (err < 0)
return err;
+ if (!tb[IOAM6_IPTUNNEL_MODE])
+ mode = IOAM6_IPTUNNEL_MODE_INLINE;
+ else
+ mode = nla_get_u8(tb[IOAM6_IPTUNNEL_MODE]);
+
+ if (!tb[IOAM6_IPTUNNEL_DST] && mode != IOAM6_IPTUNNEL_MODE_INLINE) {
+ NL_SET_ERR_MSG(extack, "this mode needs a tunnel destination");
+ return -EINVAL;
+ }
+
if (!tb[IOAM6_IPTUNNEL_TRACE]) {
NL_SET_ERR_MSG(extack, "missing trace");
return -EINVAL;
@@ -102,15 +124,24 @@ static int ioam6_build_state(struct net *net, struct nlattr *nla,
return -EINVAL;
}
- len = sizeof(*tuninfo) + trace->remlen * 4;
- len_aligned = ALIGN(len, 8);
-
- s = lwtunnel_state_alloc(len_aligned);
- if (!s)
+ len_aligned = ALIGN(trace->remlen * 4, 8);
+ lwt = lwtunnel_state_alloc(sizeof(*ilwt) + len_aligned);
+ if (!lwt)
return -ENOMEM;
- tuninfo = ioam6_lwt_info(s);
- tuninfo->eh.hdrlen = (len_aligned >> 3) - 1;
+ ilwt = ioam6_lwt_state(lwt);
+ err = dst_cache_init(&ilwt->cache, GFP_ATOMIC);
+ if (err) {
+ kfree(lwt);
+ return err;
+ }
+
+ ilwt->mode = mode;
+ if (tb[IOAM6_IPTUNNEL_DST])
+ ilwt->tundst = nla_get_in6_addr(tb[IOAM6_IPTUNNEL_DST]);
+
+ tuninfo = ioam6_lwt_info(lwt);
+ tuninfo->eh.hdrlen = ((sizeof(*tuninfo) + len_aligned) >> 3) - 1;
tuninfo->pad[0] = IPV6_TLV_PADN;
tuninfo->ioamh.type = IOAM6_TYPE_PREALLOC;
tuninfo->ioamh.opt_type = IPV6_TLV_IOAM;
@@ -119,27 +150,39 @@ static int ioam6_build_state(struct net *net, struct nlattr *nla,
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) {
+ if (len_aligned - trace->remlen * 4) {
tuninfo->traceh.data[trace->remlen * 4] = IPV6_TLV_PADN;
- tuninfo->traceh.data[trace->remlen * 4 + 1] = len - 2;
+ tuninfo->traceh.data[trace->remlen * 4 + 1] = 2;
}
- s->type = LWTUNNEL_ENCAP_IOAM6;
- s->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT;
+ lwt->type = LWTUNNEL_ENCAP_IOAM6;
+ lwt->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT;
- *ts = s;
+ *ts = lwt;
return 0;
}
-static int ioam6_do_inline(struct sk_buff *skb, struct ioam6_lwt_encap *tuninfo)
+static int ioam6_do_fill(struct net *net, struct sk_buff *skb)
{
struct ioam6_trace_hdr *trace;
- struct ipv6hdr *oldhdr, *hdr;
struct ioam6_namespace *ns;
+
+ trace = (struct ioam6_trace_hdr *)(skb_transport_header(skb)
+ + sizeof(struct ipv6_hopopt_hdr) + 2
+ + sizeof(struct ioam6_hdr));
+
+ ns = ioam6_namespace(net, trace->namespace_id);
+ if (ns)
+ ioam6_fill_trace_data(skb, ns, trace, false);
+
+ return 0;
+}
+
+static int ioam6_do_inline(struct net *net, struct sk_buff *skb,
+ struct ioam6_lwt_encap *tuninfo)
+{
+ struct ipv6hdr *oldhdr, *hdr;
int hdrlen, err;
hdrlen = (tuninfo->eh.hdrlen + 1) << 3;
@@ -168,79 +211,195 @@ static int ioam6_do_inline(struct sk_buff *skb, struct ioam6_lwt_encap *tuninfo)
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));
+ return ioam6_do_fill(net, skb);
+}
- ns = ioam6_namespace(dev_net(skb_dst(skb)->dev), trace->namespace_id);
- if (ns)
- ioam6_fill_trace_data(skb, ns, trace);
+static int ioam6_do_encap(struct net *net, struct sk_buff *skb,
+ struct ioam6_lwt_encap *tuninfo,
+ struct in6_addr *tundst)
+{
+ struct dst_entry *dst = skb_dst(skb);
+ struct ipv6hdr *hdr, *inner_hdr;
+ int hdrlen, len, err;
- return 0;
+ hdrlen = (tuninfo->eh.hdrlen + 1) << 3;
+ len = sizeof(*hdr) + hdrlen;
+
+ err = skb_cow_head(skb, len + skb->mac_len);
+ if (unlikely(err))
+ return err;
+
+ inner_hdr = ipv6_hdr(skb);
+
+ skb_push(skb, len);
+ skb_reset_network_header(skb);
+ skb_mac_header_rebuild(skb);
+ skb_set_transport_header(skb, sizeof(*hdr));
+
+ tuninfo->eh.nexthdr = NEXTHDR_IPV6;
+ memcpy(skb_transport_header(skb), (u8 *)tuninfo, hdrlen);
+
+ hdr = ipv6_hdr(skb);
+ memcpy(hdr, inner_hdr, sizeof(*hdr));
+
+ hdr->nexthdr = NEXTHDR_HOP;
+ hdr->payload_len = cpu_to_be16(skb->len - sizeof(*hdr));
+ hdr->daddr = *tundst;
+ ipv6_dev_get_saddr(net, dst->dev, &hdr->daddr,
+ IPV6_PREFER_SRC_PUBLIC, &hdr->saddr);
+
+ skb_postpush_rcsum(skb, hdr, len);
+
+ return ioam6_do_fill(net, skb);
}
static int ioam6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
- struct lwtunnel_state *lwt = skb_dst(skb)->lwtstate;
+ struct dst_entry *dst = skb_dst(skb);
+ struct in6_addr orig_daddr;
+ struct ioam6_lwt *ilwt;
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))
+ ilwt = ioam6_lwt_state(dst->lwtstate);
+ orig_daddr = ipv6_hdr(skb)->daddr;
+
+ switch (ilwt->mode) {
+ case IOAM6_IPTUNNEL_MODE_INLINE:
+do_inline:
+ /* Direct insertion - if there is no Hop-by-Hop yet */
+ if (ipv6_hdr(skb)->nexthdr == NEXTHDR_HOP)
+ goto out;
+
+ err = ioam6_do_inline(net, skb, &ilwt->tuninfo);
+ if (unlikely(err))
+ goto drop;
+
+ break;
+ case IOAM6_IPTUNNEL_MODE_ENCAP:
+do_encap:
+ /* Encapsulation (ip6ip6) */
+ err = ioam6_do_encap(net, skb, &ilwt->tuninfo, &ilwt->tundst);
+ if (unlikely(err))
+ goto drop;
+
+ break;
+ case IOAM6_IPTUNNEL_MODE_AUTO:
+ /* Automatic (RFC8200 compliant):
+ * - local packets -> INLINE mode
+ * - in-transit packets -> ENCAP mode
+ */
+ if (!skb->dev)
+ goto do_inline;
+
+ goto do_encap;
+ default:
goto drop;
+ }
- err = skb_cow_head(skb, LL_RESERVED_SPACE(skb_dst(skb)->dev));
+ err = skb_cow_head(skb, LL_RESERVED_SPACE(dst->dev));
if (unlikely(err))
goto drop;
+ if (!ipv6_addr_equal(&orig_daddr, &ipv6_hdr(skb)->daddr)) {
+ preempt_disable();
+ dst = dst_cache_get(&ilwt->cache);
+ preempt_enable();
+
+ if (unlikely(!dst)) {
+ struct ipv6hdr *hdr = ipv6_hdr(skb);
+ struct flowi6 fl6;
+
+ memset(&fl6, 0, sizeof(fl6));
+ fl6.daddr = hdr->daddr;
+ fl6.saddr = hdr->saddr;
+ fl6.flowlabel = ip6_flowinfo(hdr);
+ fl6.flowi6_mark = skb->mark;
+ fl6.flowi6_proto = hdr->nexthdr;
+
+ dst = ip6_route_output(net, NULL, &fl6);
+ if (dst->error) {
+ err = dst->error;
+ dst_release(dst);
+ goto drop;
+ }
+
+ preempt_disable();
+ dst_cache_set_ip6(&ilwt->cache, dst, &fl6.saddr);
+ preempt_enable();
+ }
+
+ skb_dst_drop(skb);
+ skb_dst_set(skb, dst);
+
+ return dst_output(net, sk, skb);
+ }
out:
- return lwt->orig_output(net, sk, skb);
-
+ return dst->lwtstate->orig_output(net, sk, skb);
drop:
kfree_skb(skb);
return err;
}
+static void ioam6_destroy_state(struct lwtunnel_state *lwt)
+{
+ dst_cache_destroy(&ioam6_lwt_state(lwt)->cache);
+}
+
static int ioam6_fill_encap_info(struct sk_buff *skb,
struct lwtunnel_state *lwtstate)
{
- struct ioam6_trace_hdr *trace;
+ struct ioam6_lwt *ilwt = ioam6_lwt_state(lwtstate);
int err;
- trace = ioam6_lwt_trace(lwtstate);
-
- err = nla_put(skb, IOAM6_IPTUNNEL_TRACE, sizeof(*trace), trace);
+ err = nla_put_u8(skb, IOAM6_IPTUNNEL_MODE, ilwt->mode);
if (err)
- return err;
+ goto ret;
- return 0;
+ if (ilwt->mode != IOAM6_IPTUNNEL_MODE_INLINE) {
+ err = nla_put_in6_addr(skb, IOAM6_IPTUNNEL_DST, &ilwt->tundst);
+ if (err)
+ goto ret;
+ }
+
+ err = nla_put(skb, IOAM6_IPTUNNEL_TRACE, sizeof(ilwt->tuninfo.traceh),
+ &ilwt->tuninfo.traceh);
+ret:
+ return err;
}
static int ioam6_encap_nlsize(struct lwtunnel_state *lwtstate)
{
- struct ioam6_trace_hdr *trace = ioam6_lwt_trace(lwtstate);
+ struct ioam6_lwt *ilwt = ioam6_lwt_state(lwtstate);
+ int nlsize;
+
+ nlsize = nla_total_size(sizeof(ilwt->mode)) +
+ nla_total_size(sizeof(ilwt->tuninfo.traceh));
- return nla_total_size(sizeof(*trace));
+ if (ilwt->mode != IOAM6_IPTUNNEL_MODE_INLINE)
+ nlsize += nla_total_size(sizeof(ilwt->tundst));
+
+ return nlsize;
}
static int ioam6_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
{
- struct ioam6_trace_hdr *a_hdr = ioam6_lwt_trace(a);
- struct ioam6_trace_hdr *b_hdr = ioam6_lwt_trace(b);
-
- return (a_hdr->namespace_id != b_hdr->namespace_id);
+ struct ioam6_trace_hdr *trace_a = ioam6_lwt_trace(a);
+ struct ioam6_trace_hdr *trace_b = ioam6_lwt_trace(b);
+ struct ioam6_lwt *ilwt_a = ioam6_lwt_state(a);
+ struct ioam6_lwt *ilwt_b = ioam6_lwt_state(b);
+
+ return (ilwt_a->mode != ilwt_b->mode ||
+ (ilwt_a->mode != IOAM6_IPTUNNEL_MODE_INLINE &&
+ !ipv6_addr_equal(&ilwt_a->tundst, &ilwt_b->tundst)) ||
+ trace_a->namespace_id != trace_b->namespace_id);
}
static const struct lwtunnel_encap_ops ioam6_iptun_ops = {
.build_state = ioam6_build_state,
+ .destroy_state = ioam6_destroy_state,
.output = ioam6_output,
.fill_encap = ioam6_fill_encap_info,
.get_encap_size = ioam6_encap_nlsize,
This patch adds support for the ip6ip6 encapsulation by providing three encap modes: inline, encap and auto. Signed-off-by: Justin Iurman <justin.iurman@uliege.be> --- include/uapi/linux/ioam6_iptunnel.h | 29 ++++ net/ipv6/Kconfig | 6 +- net/ipv6/ioam6_iptunnel.c | 261 ++++++++++++++++++++++------ 3 files changed, 242 insertions(+), 54 deletions(-)