Commit a4356b29 authored by Ilpo Järvinen's avatar Ilpo Järvinen Committed by David S. Miller
Browse files

tcp: Add tcp_parse_aligned_timestamp 



Some duplicated code lying around. Located with my suffix tree
tool.

Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 2cf46637

net/ipv4/tcp_input.c

+18 −19
Original line number Diff line number Diff line
@@ -3442,6 +3442,22 @@ void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx, 
	}

}



static int tcp_parse_aligned_timestamp(struct tcp_sock *tp, struct tcphdr *th)

{

	__be32 *ptr = (__be32 *)(th + 1);



	if (*ptr == htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16)

			  | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP)) {

		tp->rx_opt.saw_tstamp = 1;

		++ptr;

		tp->rx_opt.rcv_tsval = ntohl(*ptr);

		++ptr;

		tp->rx_opt.rcv_tsecr = ntohl(*ptr);

		return 1;

	}

	return 0;

}



/* Fast parse options. This hopes to only see timestamps.

 * If it is wrong it falls back on tcp_parse_options().

 */
@@ -3453,17 +3469,9 @@ static int tcp_fast_parse_options(struct sk_buff *skb, struct tcphdr *th, 
		return 0;

	} else if (tp->rx_opt.tstamp_ok &&

		   th->doff == (sizeof(struct tcphdr)>>2)+(TCPOLEN_TSTAMP_ALIGNED>>2)) {

		__be32 *ptr = (__be32 *)(th + 1);

		if (*ptr == htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16)

				  | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP)) {

			tp->rx_opt.saw_tstamp = 1;

			++ptr;

			tp->rx_opt.rcv_tsval = ntohl(*ptr);

			++ptr;

			tp->rx_opt.rcv_tsecr = ntohl(*ptr);

		if (tcp_parse_aligned_timestamp(tp, th))

			return 1;

	}

	}

	tcp_parse_options(skb, &tp->rx_opt, 1);

	return 1;

}
@@ -4822,19 +4830,10 @@ int tcp_rcv_established(struct sock *sk, struct sk_buff *skb, 


		/* Check timestamp */

		if (tcp_header_len == sizeof(struct tcphdr) + TCPOLEN_TSTAMP_ALIGNED) {

			__be32 *ptr = (__be32 *)(th + 1);



			/* No? Slow path! */

			if (*ptr != htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16)

					  | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP))

			if (!tcp_parse_aligned_timestamp(tp, th))

				goto slow_path;



			tp->rx_opt.saw_tstamp = 1;

			++ptr;

			tp->rx_opt.rcv_tsval = ntohl(*ptr);

			++ptr;

			tp->rx_opt.rcv_tsecr = ntohl(*ptr);



			/* If PAWS failed, check it more carefully in slow path */

			if ((s32)(tp->rx_opt.rcv_tsval - tp->rx_opt.ts_recent) < 0)

				goto slow_path;