Update to FreeBSD head 2018-04-01

Git mirror commit 8dfb1ccc26d1cea7e2529303003ff61f9f1784c4.

Update #3472.

1 files changed, 67 insertions, 29 deletions

diff --git a/freebsd/sys/netinet/tcp_output.c b/freebsd/sys/netinet/tcp_output.c
index d0f08e3a..8762407f 100644
--- a/freebsd/sys/netinet/tcp_output.c
+++ b/freebsd/sys/netinet/tcp_output.c
@@ -73,17 +73,16 @@ __FBSDID("$FreeBSD$");
 #include <netinet/ip6.h>
 #include <netinet6/ip6_var.h>
 #endif
-#ifdef TCP_RFC7413
-#include <netinet/tcp_fastopen.h>
-#endif
 #include <netinet/tcp.h>
 #define	TCPOUTFLAGS
 #include <netinet/tcp_fsm.h>
+#include <netinet/tcp_log_buf.h>
 #include <netinet/tcp_seq.h>
 #include <netinet/tcp_timer.h>
 #include <netinet/tcp_var.h>
 #include <netinet/tcpip.h>
 #include <netinet/cc/cc.h>
+#include <netinet/tcp_fastopen.h>
 #ifdef TCPPCAP
 #include <netinet/tcp_pcap.h>
 #endif
@@ -214,6 +213,8 @@ tcp_output(struct tcpcb *tp)
 	struct sackhole *p;
 	int tso, mtu;
 	struct tcpopt to;
+	unsigned int wanted_cookie = 0;
+	unsigned int dont_sendalot = 0;
 #if 0
 	int maxburst = TCP_MAXBURST;
 #endif
@@ -231,7 +232,6 @@ tcp_output(struct tcpcb *tp)
 		return (tcp_offload_output(tp));
 #endif
 
-#ifdef TCP_RFC7413
 	/*
 	 * For TFO connections in SYN_RECEIVED, only allow the initial
 	 * SYN|ACK and those sent by the retransmit timer.
@@ -239,9 +239,9 @@ tcp_output(struct tcpcb *tp)
 	if (IS_FASTOPEN(tp->t_flags) &&
 	    (tp->t_state == TCPS_SYN_RECEIVED) &&
 	    SEQ_GT(tp->snd_max, tp->snd_una) &&    /* initial SYN|ACK sent */
-	    (tp->snd_nxt != tp->snd_una))          /* not a retransmit */
+	    (tp->snd_nxt != tp->snd_una))         /* not a retransmit */
 		return (0);
-#endif
+
 	/*
 	 * Determine length of data that should be transmitted,
 	 * and flags that will be used.
@@ -427,7 +427,6 @@ after_sack_rexmit:
 	if ((flags & TH_SYN) && SEQ_GT(tp->snd_nxt, tp->snd_una)) {
 		if (tp->t_state != TCPS_SYN_RECEIVED)
 			flags &= ~TH_SYN;
-#ifdef TCP_RFC7413
 		/*
 		 * When sending additional segments following a TFO SYN|ACK,
 		 * do not include the SYN bit.
@@ -435,7 +434,6 @@ after_sack_rexmit:
 		if (IS_FASTOPEN(tp->t_flags) &&
 		    (tp->t_state == TCPS_SYN_RECEIVED))
 			flags &= ~TH_SYN;
-#endif
 		off--, len++;
 	}
 
@@ -449,17 +447,24 @@ after_sack_rexmit:
 		flags &= ~TH_FIN;
 	}
 
-#ifdef TCP_RFC7413
 	/*
-	 * When retransmitting SYN|ACK on a passively-created TFO socket,
-	 * don't include data, as the presence of data may have caused the
-	 * original SYN|ACK to have been dropped by a middlebox.
+	 * On TFO sockets, ensure no data is sent in the following cases:
+	 *
+	 *  - When retransmitting SYN|ACK on a passively-created socket
+	 *
+	 *  - When retransmitting SYN on an actively created socket
+	 *
+	 *  - When sending a zero-length cookie (cookie request) on an
+	 *    actively created socket
+	 *
+	 *  - When the socket is in the CLOSED state (RST is being sent)
 	 */
 	if (IS_FASTOPEN(tp->t_flags) &&
-	    (((tp->t_state == TCPS_SYN_RECEIVED) && (tp->t_rxtshift > 0)) ||
+	    (((flags & TH_SYN) && (tp->t_rxtshift > 0)) ||
+	     ((tp->t_state == TCPS_SYN_SENT) &&
+	      (tp->t_tfo_client_cookie_len == 0)) ||
 	     (flags & TH_RST)))
 		len = 0;
-#endif
 	if (len <= 0) {
 		/*
 		 * If FIN has been sent but not acked,
@@ -543,7 +548,7 @@ after_sack_rexmit:
 	if ((tp->t_flags & TF_TSO) && V_tcp_do_tso && len > tp->t_maxseg &&
 	    ((tp->t_flags & TF_SIGNATURE) == 0) &&
 	    tp->rcv_numsacks == 0 && sack_rxmit == 0 &&
-	    ipoptlen == 0)
+	    ipoptlen == 0 && !(flags & TH_SYN))
 		tso = 1;
 
 	if (sack_rxmit) {
@@ -763,22 +768,39 @@ send:
 			tp->snd_nxt = tp->iss;
 			to.to_mss = tcp_mssopt(&tp->t_inpcb->inp_inc);
 			to.to_flags |= TOF_MSS;
-#ifdef TCP_RFC7413
+
 			/*
-			 * Only include the TFO option on the first
-			 * transmission of the SYN|ACK on a
-			 * passively-created TFO socket, as the presence of
-			 * the TFO option may have caused the original
-			 * SYN|ACK to have been dropped by a middlebox.
+			 * On SYN or SYN|ACK transmits on TFO connections,
+			 * only include the TFO option if it is not a
+			 * retransmit, as the presence of the TFO option may
+			 * have caused the original SYN or SYN|ACK to have
+			 * been dropped by a middlebox.
 			 */
 			if (IS_FASTOPEN(tp->t_flags) &&
-			    (tp->t_state == TCPS_SYN_RECEIVED) &&
 			    (tp->t_rxtshift == 0)) {
-				to.to_tfo_len = TCP_FASTOPEN_COOKIE_LEN;
-				to.to_tfo_cookie = (u_char *)&tp->t_tfo_cookie;
-				to.to_flags |= TOF_FASTOPEN;
+				if (tp->t_state == TCPS_SYN_RECEIVED) {
+					to.to_tfo_len = TCP_FASTOPEN_COOKIE_LEN;
+					to.to_tfo_cookie =
+					    (u_int8_t *)&tp->t_tfo_cookie.server;
+					to.to_flags |= TOF_FASTOPEN;
+					wanted_cookie = 1;
+				} else if (tp->t_state == TCPS_SYN_SENT) {
+					to.to_tfo_len =
+					    tp->t_tfo_client_cookie_len;
+					to.to_tfo_cookie =
+					    tp->t_tfo_cookie.client;
+					to.to_flags |= TOF_FASTOPEN;
+					wanted_cookie = 1;
+					/*
+					 * If we wind up having more data to
+					 * send with the SYN than can fit in
+					 * one segment, don't send any more
+					 * until the SYN|ACK comes back from
+					 * the other end.
+					 */
+					dont_sendalot = 1;
+				}
 			}
-#endif
 		}
 		/* Window scaling. */
 		if ((flags & TH_SYN) && (tp->t_flags & TF_REQ_SCALE)) {
@@ -822,6 +844,13 @@ send:
 
 		/* Processing the options. */
 		hdrlen += optlen = tcp_addoptions(&to, opt);
+		/*
+		 * If we wanted a TFO option to be added, but it was unable
+		 * to fit, ensure no data is sent.
+		 */
+		if (IS_FASTOPEN(tp->t_flags) && wanted_cookie &&
+		    !(to.to_flags & TOF_FASTOPEN))
+			len = 0;
 	}
 
 	/*
@@ -966,6 +995,8 @@ send:
 		} else {
 			len = tp->t_maxseg - optlen - ipoptlen;
 			sendalot = 1;
+			if (dont_sendalot)
+				sendalot = 0;
 		}
 	} else
 		tso = 0;
@@ -1282,6 +1313,10 @@ send:
 	}
 #endif
 
+	/* We're getting ready to send; log now. */
+	TCP_LOG_EVENT(tp, th, &so->so_rcv, &so->so_snd, TCP_LOG_OUT, ERRNO_UNK,
+	    len, NULL, false);
+
 	/*
 	 * Enable TSO and specify the size of the segments.
 	 * The TCP pseudo header checksum is always provided.
@@ -1521,6 +1556,9 @@ timer:
 	}
 
 	if (error) {
+		/* Record the error. */
+		TCP_LOG_EVENT(tp, NULL, &so->so_rcv, &so->so_snd, TCP_LOG_OUT,
+		    error, 0, NULL, false);
 
 		/*
 		 * We know that the packet was lost, so back out the
@@ -1769,15 +1807,16 @@ tcp_addoptions(struct tcpopt *to, u_char *optp)
 			TCPSTAT_INC(tcps_sack_send_blocks);
 			break;
 			}
-#ifdef TCP_RFC7413
 		case TOF_FASTOPEN:
 			{
 			int total_len;
 
 			/* XXX is there any point to aligning this option? */
 			total_len = TCPOLEN_FAST_OPEN_EMPTY + to->to_tfo_len;
-			if (TCP_MAXOLEN - optlen < total_len)
+			if (TCP_MAXOLEN - optlen < total_len) {
+				to->to_flags &= ~TOF_FASTOPEN;
 				continue;
+			}
 			*optp++ = TCPOPT_FAST_OPEN;
 			*optp++ = total_len;
 			if (to->to_tfo_len > 0) {
@@ -1787,7 +1826,6 @@ tcp_addoptions(struct tcpopt *to, u_char *optp)
 			optlen += total_len;
 			break;
 			}
-#endif
 		default:
 			panic("%s: unknown TCP option type", __func__);
 			break;