[RFC PATCH bpf-next 6/8] bpf: Add cookie in sk_reuseport_md.
From: Kuniyuki Iwashima <hidden>
Date: 2020-11-17 09:42:49
Also in:
bpf, lkml
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), networking [general], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
We will call sock_reuseport.prog for socket migration in the next commit, so the eBPF program has to know which listener is closing in order to select the new listener. Currently, we can get a unique ID for each listener in the userspace by calling bpf_map_lookup_elem() for BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map. This patch exposes the ID to the eBPF program. Reviewed-by: Benjamin Herrenschmidt <redacted> Signed-off-by: Kuniyuki Iwashima <redacted> --- include/linux/bpf.h | 1 + include/uapi/linux/bpf.h | 1 + net/core/filter.c | 8 ++++++++ tools/include/uapi/linux/bpf.h | 1 + 4 files changed, 11 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 581b2a2e78eb..c0646eceffa2 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h@@ -1897,6 +1897,7 @@ struct sk_reuseport_kern { u32 hash; u32 reuseport_id; bool bind_inany; + u64 cookie; }; bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type, struct bpf_insn_access_aux *info);
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 162999b12790..3fcddb032838 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h@@ -4403,6 +4403,7 @@ struct sk_reuseport_md { __u32 ip_protocol; /* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */ __u32 bind_inany; /* Is sock bound to an INANY address? */ __u32 hash; /* A hash of the packet 4 tuples */ + __u64 cookie; /* ID of the listener in map */ }; #define BPF_TAG_SIZE 8
diff --git a/net/core/filter.c b/net/core/filter.c
index 2ca5eecebacf..01e28f283962 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c@@ -9862,6 +9862,7 @@ static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern, reuse_kern->hash = hash; reuse_kern->reuseport_id = reuse->reuseport_id; reuse_kern->bind_inany = reuse->bind_inany; + reuse_kern->cookie = sock_gen_cookie(sk); } struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
@@ -10010,6 +10011,9 @@ sk_reuseport_is_valid_access(int off, int size, case offsetof(struct sk_reuseport_md, hash): return size == size_default; + case bpf_ctx_range(struct sk_reuseport_md, cookie): + return size == sizeof(__u64); + /* Fields that allow narrowing */ case bpf_ctx_range(struct sk_reuseport_md, eth_protocol): if (size < sizeof_field(struct sk_buff, protocol))
@@ -10082,6 +10086,10 @@ static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type, case offsetof(struct sk_reuseport_md, bind_inany): SK_REUSEPORT_LOAD_FIELD(bind_inany); break; + + case offsetof(struct sk_reuseport_md, cookie): + SK_REUSEPORT_LOAD_FIELD(cookie); + break; } return insn - insn_buf;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 162999b12790..3fcddb032838 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h@@ -4403,6 +4403,7 @@ struct sk_reuseport_md { __u32 ip_protocol; /* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */ __u32 bind_inany; /* Is sock bound to an INANY address? */ __u32 hash; /* A hash of the packet 4 tuples */ + __u64 cookie; /* ID of the listener in map */ }; #define BPF_TAG_SIZE 8
--
2.17.2 (Apple Git-113)