net: add missing SOF_TIMESTAMPING_OPT_ID support

SOF_TIMESTAMPING_OPT_ID is supported on TCP, UDP and RAW sockets.
But it was missing on RAW with IPPROTO_IP, PF_PACKET and CAN.

Add skb_setup_tx_timestamp that configures both tx_flags and tskey
for these paths that do not need corking or use bytestream keys.

Fixes: 09c2d251 ("net-timestamp: add key to disambiguate concurrent datagrams")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sock.h

@@ -2340,22 +2340,39 @@ static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
 
 /**
- * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
+ * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
  * @sk:		socket sending this packet
  * @tsflags:	timestamping flags to use
  * @tx_flags:	completed with instructions for time stamping
+ * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
  *
  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
  */
-static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
-				     __u8 *tx_flags)
+static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
+				      __u8 *tx_flags, __u32 *tskey)
 {
-	if (unlikely(tsflags))
+	if (unlikely(tsflags)) {
 		__sock_tx_timestamp(tsflags, tx_flags);
+		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
+		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
+			*tskey = sk->sk_tskey++;
+	}
 	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
 		*tx_flags |= SKBTX_WIFI_STATUS;
 }
 
+static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
+				     __u8 *tx_flags)
+{
+	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
+}
+
+static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
+{
+	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
+			   &skb_shinfo(skb)->tskey);
+}
+
 /**
  * sk_eat_skb - Release a skb if it is no longer needed
  * @sk: socket to eat this skb from

net/can/raw.c

@@ -771,7 +771,7 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	if (err < 0)
 		goto free_skb;
 
-	sock_tx_timestamp(sk, sk->sk_tsflags, &skb_shinfo(skb)->tx_flags);
+	skb_setup_tx_timestamp(skb, sk->sk_tsflags);
 
 	skb->dev = dev;
 	skb->sk  = sk;

net/ipv4/raw.c

@@ -391,7 +391,7 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
 
 	skb->ip_summed = CHECKSUM_NONE;
 
-	sock_tx_timestamp(sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);
+	skb_setup_tx_timestamp(skb, sockc->tsflags);
 
 	if (flags & MSG_CONFIRM)
 		skb_set_dst_pending_confirm(skb, 1);

net/ipv6/raw.c

@@ -658,7 +658,7 @@ static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
 
 	skb->ip_summed = CHECKSUM_NONE;
 
-	sock_tx_timestamp(sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);
+	skb_setup_tx_timestamp(skb, sockc->tsflags);
 
 	if (flags & MSG_CONFIRM)
 		skb_set_dst_pending_confirm(skb, 1);

net/packet/af_packet.c

@@ -1965,7 +1965,7 @@ static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
 	skb->mark = sk->sk_mark;
 	skb->tstamp = sockc.transmit_time;
 
-	sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
+	skb_setup_tx_timestamp(skb, sockc.tsflags);
 
 	if (unlikely(extra_len == 4))
 		skb->no_fcs = 1;
@@ -2460,7 +2460,7 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
 	skb->priority = po->sk.sk_priority;
 	skb->mark = po->sk.sk_mark;
 	skb->tstamp = sockc->transmit_time;
-	sock_tx_timestamp(&po->sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);
+	skb_setup_tx_timestamp(skb, sockc->tsflags);
 	skb_zcopy_set_nouarg(skb, ph.raw);
 
 	skb_reserve(skb, hlen);
@@ -2898,7 +2898,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
 		goto out_free;
 	}
 
-	sock_tx_timestamp(sk, sockc.tsflags, &skb_shinfo(skb)->tx_flags);
+	skb_setup_tx_timestamp(skb, sockc.tsflags);
 
 	if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
 	    !packet_extra_vlan_len_allowed(dev, skb)) {