lkml.org 
[lkml]   [2020]   [Dec]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v1 bpf-next 09/11] bpf: Support bpf_get_socket_cookie_sock() for BPF_PROG_TYPE_SK_REUSEPORT.
Date
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 makes the sk pointer available in sk_reuseport_md so that we can
get the ID by BPF_FUNC_get_socket_cookie() in the eBPF program.

Link: https://lore.kernel.org/netdev/20201119001154.kapwihc2plp4f7zc@kafai-mbp.dhcp.thefacebook.com/
Suggested-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
---
include/uapi/linux/bpf.h | 8 ++++++++
net/core/filter.c | 12 +++++++++++-
tools/include/uapi/linux/bpf.h | 8 ++++++++
3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index efe342bf3dbc..3e9b8bd42b4e 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1650,6 +1650,13 @@ union bpf_attr {
* A 8-byte long non-decreasing number on success, or 0 if the
* socket field is missing inside *skb*.
*
+ * u64 bpf_get_socket_cookie(struct bpf_sock *sk)
+ * Description
+ * Equivalent to bpf_get_socket_cookie() helper that accepts
+ * *skb*, but gets socket from **struct bpf_sock** context.
+ * Return
+ * A 8-byte long non-decreasing number.
+ *
* u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx)
* Description
* Equivalent to bpf_get_socket_cookie() helper that accepts
@@ -4420,6 +4427,7 @@ struct sk_reuseport_md {
__u32 bind_inany; /* Is sock bound to an INANY address? */
__u32 hash; /* A hash of the packet 4 tuples */
__u8 migration; /* Migration type */
+ __bpf_md_ptr(struct bpf_sock *, sk); /* current listening socket */
};

#define BPF_TAG_SIZE 8
diff --git a/net/core/filter.c b/net/core/filter.c
index 0a0634787bb4..1059d31847ef 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4628,7 +4628,7 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
.func = bpf_get_socket_cookie_sock,
.gpl_only = false,
.ret_type = RET_INTEGER,
- .arg1_type = ARG_PTR_TO_CTX,
+ .arg1_type = ARG_PTR_TO_SOCKET,
};

BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
@@ -9982,6 +9982,8 @@ sk_reuseport_func_proto(enum bpf_func_id func_id,
return &sk_reuseport_load_bytes_proto;
case BPF_FUNC_skb_load_bytes_relative:
return &sk_reuseport_load_bytes_relative_proto;
+ case BPF_FUNC_get_socket_cookie:
+ return &bpf_get_socket_cookie_sock_proto;
default:
return bpf_base_func_proto(func_id);
}
@@ -10015,6 +10017,10 @@ sk_reuseport_is_valid_access(int off, int size,
return prog->expected_attach_type == BPF_SK_REUSEPORT_SELECT_OR_MIGRATE &&
size == sizeof(__u8);

+ case offsetof(struct sk_reuseport_md, sk):
+ info->reg_type = PTR_TO_SOCKET;
+ 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))
@@ -10091,6 +10097,10 @@ static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
case offsetof(struct sk_reuseport_md, migration):
SK_REUSEPORT_LOAD_FIELD(migration);
break;
+
+ case offsetof(struct sk_reuseport_md, sk):
+ SK_REUSEPORT_LOAD_FIELD(sk);
+ break;
}

return insn - insn_buf;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index efe342bf3dbc..3e9b8bd42b4e 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1650,6 +1650,13 @@ union bpf_attr {
* A 8-byte long non-decreasing number on success, or 0 if the
* socket field is missing inside *skb*.
*
+ * u64 bpf_get_socket_cookie(struct bpf_sock *sk)
+ * Description
+ * Equivalent to bpf_get_socket_cookie() helper that accepts
+ * *skb*, but gets socket from **struct bpf_sock** context.
+ * Return
+ * A 8-byte long non-decreasing number.
+ *
* u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx)
* Description
* Equivalent to bpf_get_socket_cookie() helper that accepts
@@ -4420,6 +4427,7 @@ struct sk_reuseport_md {
__u32 bind_inany; /* Is sock bound to an INANY address? */
__u32 hash; /* A hash of the packet 4 tuples */
__u8 migration; /* Migration type */
+ __bpf_md_ptr(struct bpf_sock *, sk); /* current listening socket */
};

#define BPF_TAG_SIZE 8
--
2.17.2 (Apple Git-113)
\
 
 \ /
  Last update: 2020-12-01 16:10    [W:0.363 / U:0.152 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site