v2:
- fix warnings
Add generic netlink multicast event support to ioam6 as another solution
to share IOAM data with user space. The other one being via IPv6 raw
sockets combined with ancillary data. This patchset focuses on the IOAM
Pre-allocated Trace (the only Option-Type currently supported), and so
on IOAM "trace" events. See an example of a consumer here [1].
[1] https://github.com/Advanced-Observability/ioam-agent-python/blob/netlink_event/ioam-agent.py
Justin Iurman (3):
uapi: ioam6: API for netlink multicast events
net: ioam6: multicast event
net: exthdrs: ioam6: send trace event
include/net/ioam6.h | 4 +++
include/uapi/linux/ioam6_genl.h | 20 +++++++++++
net/ipv6/exthdrs.c | 6 ++++
net/ipv6/ioam6.c | 64 +++++++++++++++++++++++++++++++++
4 files changed, 94 insertions(+)
base-commit: a6e0cb150c514efba4aaba4069927de43d80bb59
--
2.34.1
Add a multicast group to the ioam6 generic netlink family and provide
ioam6_event() to send an ioam6 event to the multicast group.
Signed-off-by: Justin Iurman <[email protected]>
---
include/net/ioam6.h | 4 +++
net/ipv6/ioam6.c | 64 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 68 insertions(+)
diff --git a/include/net/ioam6.h b/include/net/ioam6.h
index 781d2d8b2f29..2cbbee6e806a 100644
--- a/include/net/ioam6.h
+++ b/include/net/ioam6.h
@@ -12,6 +12,7 @@
#include <linux/net.h>
#include <linux/ipv6.h>
#include <linux/ioam6.h>
+#include <linux/ioam6_genl.h>
#include <linux/rhashtable-types.h>
struct ioam6_namespace {
@@ -65,4 +66,7 @@ void ioam6_exit(void);
int ioam6_iptunnel_init(void);
void ioam6_iptunnel_exit(void);
+void ioam6_event(enum ioam6_event_type type, struct net *net, gfp_t gfp,
+ void *opt, unsigned int opt_len);
+
#endif /* _NET_IOAM6_H */
diff --git a/net/ipv6/ioam6.c b/net/ipv6/ioam6.c
index 571f0e4d9cf3..5fa923f06632 100644
--- a/net/ipv6/ioam6.c
+++ b/net/ipv6/ioam6.c
@@ -612,6 +612,68 @@ static const struct genl_ops ioam6_genl_ops[] = {
},
};
+#define IOAM6_GENL_EV_GRP_OFFSET 0
+
+static const struct genl_multicast_group ioam6_mcgrps[] = {
+ [IOAM6_GENL_EV_GRP_OFFSET] = { .name = IOAM6_GENL_EV_GRP_NAME,
+ .flags = GENL_MCAST_CAP_NET_ADMIN },
+};
+
+static int ioam6_event_put_trace(struct sk_buff *skb,
+ struct ioam6_trace_hdr *trace,
+ unsigned int len)
+{
+ if (nla_put_u16(skb, IOAM6_EVENT_ATTR_TRACE_NAMESPACE,
+ be16_to_cpu(trace->namespace_id)) ||
+ nla_put_u8(skb, IOAM6_EVENT_ATTR_TRACE_NODELEN, trace->nodelen) ||
+ nla_put_u32(skb, IOAM6_EVENT_ATTR_TRACE_TYPE,
+ be32_to_cpu(trace->type_be32)) ||
+ nla_put(skb, IOAM6_EVENT_ATTR_TRACE_DATA,
+ len - sizeof(struct ioam6_trace_hdr) - trace->remlen * 4,
+ trace->data + trace->remlen * 4))
+ return 1;
+
+ return 0;
+}
+
+void ioam6_event(enum ioam6_event_type type, struct net *net, gfp_t gfp,
+ void *opt, unsigned int opt_len)
+{
+ struct nlmsghdr *nlh;
+ struct sk_buff *skb;
+
+ if (!genl_has_listeners(&ioam6_genl_family, net,
+ IOAM6_GENL_EV_GRP_OFFSET))
+ return;
+
+ skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
+ if (!skb)
+ return;
+
+ nlh = genlmsg_put(skb, 0, 0, &ioam6_genl_family, 0, type);
+ if (!nlh)
+ goto nla_put_failure;
+
+ switch (type) {
+ case IOAM6_EVENT_UNSPEC:
+ WARN_ON_ONCE(1);
+ break;
+ case IOAM6_EVENT_TRACE:
+ if (ioam6_event_put_trace(skb, (struct ioam6_trace_hdr *)opt,
+ opt_len))
+ goto nla_put_failure;
+ break;
+ }
+
+ genlmsg_end(skb, nlh);
+ genlmsg_multicast_netns(&ioam6_genl_family, net, skb, 0,
+ IOAM6_GENL_EV_GRP_OFFSET, gfp);
+ return;
+
+nla_put_failure:
+ nlmsg_free(skb);
+}
+
static struct genl_family ioam6_genl_family __ro_after_init = {
.name = IOAM6_GENL_NAME,
.version = IOAM6_GENL_VERSION,
@@ -620,6 +682,8 @@ static struct genl_family ioam6_genl_family __ro_after_init = {
.ops = ioam6_genl_ops,
.n_ops = ARRAY_SIZE(ioam6_genl_ops),
.resv_start_op = IOAM6_CMD_NS_SET_SCHEMA + 1,
+ .mcgrps = ioam6_mcgrps,
+ .n_mcgrps = ARRAY_SIZE(ioam6_mcgrps),
.module = THIS_MODULE,
};
--
2.34.1
Add new api to support ioam6 events for generic netlink multicast. A
first "trace" event is added to the list of ioam6 events, which will
represent an IOAM Pre-allocated (or Incremental) Trace Option-Type. It
provides another solution to share IOAM data with user space.
Suggested-By: Paolo Abeni <[email protected]>
Signed-off-by: Justin Iurman <[email protected]>
---
include/uapi/linux/ioam6_genl.h | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/include/uapi/linux/ioam6_genl.h b/include/uapi/linux/ioam6_genl.h
index ca4b22833754..1733fbc51fb5 100644
--- a/include/uapi/linux/ioam6_genl.h
+++ b/include/uapi/linux/ioam6_genl.h
@@ -49,4 +49,24 @@ enum {
#define IOAM6_CMD_MAX (__IOAM6_CMD_MAX - 1)
+#define IOAM6_GENL_EV_GRP_NAME "ioam6_events"
+
+enum ioam6_event_type {
+ IOAM6_EVENT_UNSPEC,
+ IOAM6_EVENT_TRACE,
+};
+
+enum ioam6_event_attr {
+ IOAM6_EVENT_ATTR_UNSPEC,
+
+ IOAM6_EVENT_ATTR_TRACE_NAMESPACE, /* u16 */
+ IOAM6_EVENT_ATTR_TRACE_NODELEN, /* u8 */
+ IOAM6_EVENT_ATTR_TRACE_TYPE, /* u32 */
+ IOAM6_EVENT_ATTR_TRACE_DATA, /* Binary */
+
+ __IOAM6_EVENT_ATTR_MAX
+};
+
+#define IOAM6_EVENT_ATTR_MAX (__IOAM6_EVENT_ATTR_MAX - 1)
+
#endif /* _UAPI_LINUX_IOAM6_GENL_H */
--
2.34.1
If we're processing an IOAM Pre-allocated Trace Option-Type (the only
one supported currently), and if we're the destination, then send the
trace as an ioam6 event to the multicast group. This way, user space
apps will be able to collect IOAM data (for a trace, it only makes sense
to send events if we're the destination).
Signed-off-by: Justin Iurman <[email protected]>
---
net/ipv6/exthdrs.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 4952ae792450..b26dcf4d0239 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -50,6 +50,7 @@
#endif
#include <net/rpl.h>
#include <linux/ioam6.h>
+#include <linux/ioam6_genl.h>
#include <net/ioam6.h>
#include <net/dst_metadata.h>
@@ -944,6 +945,11 @@ static bool ipv6_hop_ioam(struct sk_buff *skb, int optoff)
ip6_route_input(skb);
ioam6_fill_trace_data(skb, ns, trace, true);
+
+ if (skb_dst(skb)->dev->flags & IFF_LOOPBACK)
+ ioam6_event(IOAM6_EVENT_TRACE, dev_net(skb->dev),
+ GFP_ATOMIC, (void *)trace,
+ hdr->opt_len - 2);
break;
default:
break;
--
2.34.1