Sets the bpf program represented by fd as an early filter in the rx path
of the netdev. The fd must have been created as BPF_PROG_TYPE_XDP.
Providing a negative value as fd clears the program. Getting the fd back
via rtnl is not possible, therefore reading of this value merely
provides a bool whether the program is valid on the link or not.
Signed-off-by: Brenden Blanco <bbla...@plumgrid.com>
---
include/uapi/linux/if_link.h | 12 +++++++++
net/core/rtnetlink.c | 64 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 76 insertions(+)
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 4285ac3..a1b5202 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -156,6 +156,7 @@ enum {
IFLA_GSO_MAX_SEGS,
IFLA_GSO_MAX_SIZE,
IFLA_PAD,
+ IFLA_XDP,
__IFLA_MAX
};
@@ -843,4 +844,15 @@ enum {
};
#define LINK_XSTATS_TYPE_MAX (__LINK_XSTATS_TYPE_MAX - 1)
+/* XDP section */
+
+enum {
+ IFLA_XDP_UNSPEC,
+ IFLA_XDP_FD,
+ IFLA_XDP_ATTACHED,
+ __IFLA_XDP_MAX,
+};
+
+#define IFLA_XDP_MAX (__IFLA_XDP_MAX - 1)
+
#endif /* _UAPI_LINUX_IF_LINK_H */
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index a9e3805..eba2b82 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -891,6 +891,16 @@ static size_t rtnl_port_size(const struct net_device *dev,
return port_self_size;
}
+static size_t rtnl_xdp_size(const struct net_device *dev)
+{
+ size_t xdp_size = nla_total_size(1); /* XDP_ATTACHED */
+
+ if (!dev->netdev_ops->ndo_xdp)
+ return 0;
+ else
+ return xdp_size;
+}
+
static noinline size_t if_nlmsg_size(const struct net_device *dev,
u32 ext_filter_mask)
{
@@ -927,6 +937,7 @@ static noinline size_t if_nlmsg_size(const struct
net_device *dev,
+ nla_total_size(MAX_PHYS_ITEM_ID_LEN) /* IFLA_PHYS_PORT_ID */
+ nla_total_size(MAX_PHYS_ITEM_ID_LEN) /* IFLA_PHYS_SWITCH_ID */
+ nla_total_size(IFNAMSIZ) /* IFLA_PHYS_PORT_NAME */
+ + rtnl_xdp_size(dev) /* IFLA_XDP */
+ nla_total_size(1); /* IFLA_PROTO_DOWN */
}
@@ -1211,6 +1222,33 @@ static int rtnl_fill_link_ifmap(struct sk_buff *skb,
struct net_device *dev)
return 0;
}
+static int rtnl_xdp_fill(struct sk_buff *skb, struct net_device *dev)
+{
+ struct netdev_xdp xdp_op = {};
+ struct nlattr *xdp;
+ int err;
+
+ if (!dev->netdev_ops->ndo_xdp)
+ return 0;
+ xdp = nla_nest_start(skb, IFLA_XDP);
+ if (!xdp)
+ return -EMSGSIZE;
+ xdp_op.command = XDP_QUERY_PROG;
+ err = dev->netdev_ops->ndo_xdp(dev, &xdp_op);
+ if (err)
+ goto err_cancel;
+ err = nla_put_u8(skb, IFLA_XDP_ATTACHED, xdp_op.prog_attached);
+ if (err)
+ goto err_cancel;
+
+ nla_nest_end(skb, xdp);
+ return 0;
+
+err_cancel:
+ nla_nest_cancel(skb, xdp);
+ return err;
+}
+
static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
int type, u32 pid, u32 seq, u32 change,
unsigned int flags, u32 ext_filter_mask)
@@ -1307,6 +1345,9 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct
net_device *dev,
if (rtnl_port_fill(skb, dev, ext_filter_mask))
goto nla_put_failure;
+ if (rtnl_xdp_fill(skb, dev))
+ goto nla_put_failure;
+
if (dev->rtnl_link_ops || rtnl_have_link_slave_info(dev)) {
if (rtnl_link_fill(skb, dev) < 0)
goto nla_put_failure;
@@ -1392,6 +1433,7 @@ static const struct nla_policy ifla_policy[IFLA_MAX+1] = {
[IFLA_PHYS_SWITCH_ID] = { .type = NLA_BINARY, .len =
MAX_PHYS_ITEM_ID_LEN },
[IFLA_LINK_NETNSID] = { .type = NLA_S32 },
[IFLA_PROTO_DOWN] = { .type = NLA_U8 },
+ [IFLA_XDP] = { .type = NLA_NESTED },
};
static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
@@ -1429,6 +1471,11 @@ static const struct nla_policy
ifla_port_policy[IFLA_PORT_MAX+1] = {
[IFLA_PORT_RESPONSE] = { .type = NLA_U16, },
};
+static const struct nla_policy ifla_xdp_policy[IFLA_XDP_MAX + 1] = {
+ [IFLA_XDP_FD] = { .type = NLA_S32 },
+ [IFLA_XDP_ATTACHED] = { .type = NLA_U8 },
+};
+
static const struct rtnl_link_ops *linkinfo_to_kind_ops(const struct nlattr
*nla)
{
const struct rtnl_link_ops *ops = NULL;
@@ -2054,6 +2101,23 @@ static int do_setlink(const struct sk_buff *skb,
status |= DO_SETLINK_NOTIFY;
}
+ if (tb[IFLA_XDP]) {
+ struct nlattr *xdp[IFLA_XDP_MAX + 1];
+
+ err = nla_parse_nested(xdp, IFLA_XDP_MAX, tb[IFLA_XDP],
+ ifla_xdp_policy);
+ if (err < 0)
+ goto errout;
+
+ if (xdp[IFLA_XDP_FD]) {
+ err = dev_change_xdp_fd(dev,
+ nla_get_s32(xdp[IFLA_XDP_FD]));
+ if (err)
+ goto errout;
+ status |= DO_SETLINK_NOTIFY;
+ }
+ }
+
errout:
if (status & DO_SETLINK_MODIFIED) {
if (status & DO_SETLINK_NOTIFY)
--
2.8.2
