From: Jason Xing <kerneljasonxing@gmail.com>
Date: Thu, 20 Feb 2025 07:29:29 +0000 (+0800)
Subject: bpf: Add networking timestamping support to bpf_get/setsockopt()
X-Git-Tag: v6.15-rc1~160^2~249^2~1^2~11
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=24e82b7c045ba5afde5bd81f691b7a72283de35e;p=thirdparty%2Fkernel%2Flinux.git

bpf: Add networking timestamping support to bpf_get/setsockopt()

The new SK_BPF_CB_FLAGS and new SK_BPF_CB_TX_TIMESTAMPING are
added to bpf_get/setsockopt. The later patches will implement the
BPF networking timestamping. The BPF program will use
bpf_setsockopt(SK_BPF_CB_FLAGS, SK_BPF_CB_TX_TIMESTAMPING) to
enable the BPF networking timestamping on a socket.

Signed-off-by: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250220072940.99994-2-kerneljasonxing@gmail.com
---

diff --git a/include/net/sock.h b/include/net/sock.h
index 60ebf3c7b229e..a95eedacae76c 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -303,6 +303,7 @@ struct sk_filter;
   *	@sk_stamp: time stamp of last packet received
   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
   *	@sk_tsflags: SO_TIMESTAMPING flags
+  *	@sk_bpf_cb_flags: used in bpf_setsockopt()
   *	@sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
   *			   Sockets that can be used under memory reclaim should
   *			   set this to false.
@@ -525,6 +526,8 @@ struct sock {
 	u8			sk_txtime_deadline_mode : 1,
 				sk_txtime_report_errors : 1,
 				sk_txtime_unused : 6;
+#define SK_BPF_CB_FLAG_TEST(SK, FLAG) ((SK)->sk_bpf_cb_flags & (FLAG))
+	u8			sk_bpf_cb_flags;
 
 	void			*sk_user_data;
 #ifdef CONFIG_SECURITY
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 2acf9b3363717..4e0632848440b 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -6913,6 +6913,12 @@ enum {
 	BPF_SOCK_OPS_ALL_CB_FLAGS       = 0x7F,
 };
 
+enum {
+	SK_BPF_CB_TX_TIMESTAMPING	= 1<<0,
+	SK_BPF_CB_MASK			= (SK_BPF_CB_TX_TIMESTAMPING - 1) |
+					   SK_BPF_CB_TX_TIMESTAMPING
+};
+
 /* List of known BPF sock_ops operators.
  * New entries can only be added at the end
  */
@@ -7091,6 +7097,7 @@ enum {
 	TCP_BPF_SYN_IP		= 1006, /* Copy the IP[46] and TCP header */
 	TCP_BPF_SYN_MAC         = 1007, /* Copy the MAC, IP[46], and TCP header */
 	TCP_BPF_SOCK_OPS_CB_FLAGS = 1008, /* Get or Set TCP sock ops flags */
+	SK_BPF_CB_FLAGS		= 1009, /* Get or set sock ops flags in socket */
 };
 
 enum {
diff --git a/net/core/filter.c b/net/core/filter.c
index ffec7b4357f9f..5b7e44dfc037c 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5222,6 +5222,25 @@ static const struct bpf_func_proto bpf_get_socket_uid_proto = {
 	.arg1_type      = ARG_PTR_TO_CTX,
 };
 
+static int sk_bpf_set_get_cb_flags(struct sock *sk, char *optval, bool getopt)
+{
+	u32 sk_bpf_cb_flags;
+
+	if (getopt) {
+		*(u32 *)optval = sk->sk_bpf_cb_flags;
+		return 0;
+	}
+
+	sk_bpf_cb_flags = *(u32 *)optval;
+
+	if (sk_bpf_cb_flags & ~SK_BPF_CB_MASK)
+		return -EINVAL;
+
+	sk->sk_bpf_cb_flags = sk_bpf_cb_flags;
+
+	return 0;
+}
+
 static int sol_socket_sockopt(struct sock *sk, int optname,
 			      char *optval, int *optlen,
 			      bool getopt)
@@ -5238,6 +5257,7 @@ static int sol_socket_sockopt(struct sock *sk, int optname,
 	case SO_MAX_PACING_RATE:
 	case SO_BINDTOIFINDEX:
 	case SO_TXREHASH:
+	case SK_BPF_CB_FLAGS:
 		if (*optlen != sizeof(int))
 			return -EINVAL;
 		break;
@@ -5247,6 +5267,9 @@ static int sol_socket_sockopt(struct sock *sk, int optname,
 		return -EINVAL;
 	}
 
+	if (optname == SK_BPF_CB_FLAGS)
+		return sk_bpf_set_get_cb_flags(sk, optval, getopt);
+
 	if (getopt) {
 		if (optname == SO_BINDTODEVICE)
 			return -EINVAL;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 2acf9b3363717..4e0632848440b 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -6913,6 +6913,12 @@ enum {
 	BPF_SOCK_OPS_ALL_CB_FLAGS       = 0x7F,
 };
 
+enum {
+	SK_BPF_CB_TX_TIMESTAMPING	= 1<<0,
+	SK_BPF_CB_MASK			= (SK_BPF_CB_TX_TIMESTAMPING - 1) |
+					   SK_BPF_CB_TX_TIMESTAMPING
+};
+
 /* List of known BPF sock_ops operators.
  * New entries can only be added at the end
  */
@@ -7091,6 +7097,7 @@ enum {
 	TCP_BPF_SYN_IP		= 1006, /* Copy the IP[46] and TCP header */
 	TCP_BPF_SYN_MAC         = 1007, /* Copy the MAC, IP[46], and TCP header */
 	TCP_BPF_SOCK_OPS_CB_FLAGS = 1008, /* Get or Set TCP sock ops flags */
+	SK_BPF_CB_FLAGS		= 1009, /* Get or set sock ops flags in socket */
 };
 
 enum {