[PATCH bpf-next v4 08/12] bpf: sockmap: add UDP support

From: Lorenz Bauer
Date: Mon Mar 09 2020 - 07:14:03 EST


Allow adding hashed UDP sockets to sockmaps.

Signed-off-by: Lorenz Bauer <lmb@xxxxxxxxxxxxxx>
Signed-off-by: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>
---
net/core/sock_map.c | 37 +++++++++++++++++++++++++++++++++----
1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index edfdce17b951..a7075b3b4489 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -11,6 +11,7 @@
#include <linux/list.h>
#include <linux/jhash.h>
#include <linux/sock_diag.h>
+#include <net/udp.h>

struct bpf_stab {
struct bpf_map map;
@@ -147,7 +148,19 @@ static int sock_map_init_proto(struct sock *sk, struct sk_psock *psock)

sock_owned_by_me(sk);

- prot = tcp_bpf_get_proto(sk, psock);
+ switch (sk->sk_type) {
+ case SOCK_STREAM:
+ prot = tcp_bpf_get_proto(sk, psock);
+ break;
+
+ case SOCK_DGRAM:
+ prot = udp_bpf_get_proto(sk, psock);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
if (IS_ERR(prot))
return PTR_ERR(prot);

@@ -162,7 +175,7 @@ static struct sk_psock *sock_map_psock_get_checked(struct sock *sk)
rcu_read_lock();
psock = sk_psock(sk);
if (psock) {
- if (sk->sk_prot->recvmsg != tcp_bpf_recvmsg) {
+ if (sk->sk_prot->close != sock_map_close) {
psock = ERR_PTR(-EBUSY);
goto out;
}
@@ -474,15 +487,31 @@ static bool sock_map_op_okay(const struct bpf_sock_ops_kern *ops)
ops->op == BPF_SOCK_OPS_TCP_LISTEN_CB;
}

-static bool sock_map_sk_is_suitable(const struct sock *sk)
+static bool sk_is_tcp(const struct sock *sk)
{
return sk->sk_type == SOCK_STREAM &&
sk->sk_protocol == IPPROTO_TCP;
}

+static bool sk_is_udp(const struct sock *sk)
+{
+ return sk->sk_type == SOCK_DGRAM &&
+ sk->sk_protocol == IPPROTO_UDP;
+}
+
+static bool sock_map_sk_is_suitable(const struct sock *sk)
+{
+ return sk_is_tcp(sk) || sk_is_udp(sk);
+}
+
static bool sock_map_sk_state_allowed(const struct sock *sk)
{
- return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_LISTEN);
+ if (sk_is_tcp(sk))
+ return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_LISTEN);
+ else if (sk_is_udp(sk))
+ return sk_hashed(sk);
+
+ return false;
}

static int sock_map_update_elem(struct bpf_map *map, void *key,
--
2.20.1