tpws: fix-seg wait before send. tune max delay.

docs/readme.md

@@ -812,7 +812,7 @@ tpws - это transparent proxy.
 --skip-nodelay				; не устанавливать в исходящих соединения TCP_NODELAY. несовместимо со split.
 --local-tcp-user-timeout=<seconds>	; таймаут соединений client-proxy (по умолчанию : 10 сек, 0 = оставить системное значение)
 --remote-tcp-user-timeout=<seconds>	; таймаут соединений proxy-target (по умолчанию : 20 сек, 0 = оставить системное значение)
---fix-seg				; исправлять неудачи tcp сегментации ценой задержек для всех клиентов и замедления
+--fix-seg=<int>				; исправлять неудачи tcp сегментации ценой задержек для всех клиентов и замедления. ждать до N мс. по умолчанию 30 мс.
 
 --split-pos=N|-N|marker+N|marker-N	; список через запятую маркеров для tcp сегментации
 --split-any-protocol			; применять сегментацию к любым пакетам. по умолчанию - только к известным протоколам (http, TLS)

tpws/helpers.c

@@ -484,10 +484,11 @@ bool socket_has_notsent(int sfd)
 
 	if (getsockopt(sfd, IPPROTO_TCP, TCP_INFO, (char *)&tcpi, &ts) < 0)
 		return false;
-	if (tcpi.tcpi_state != 1)
+	if (tcpi.tcpi_state != 1) // TCP_ESTABLISHED
 		return false;
 	size_t s = (char *)&tcpi.tcpi_notsent_bytes - (char *)&tcpi.tcpi_state;
 	if (ts < s)
+		// old structure version
 		return false;
 	return !!tcpi.tcpi_notsent_bytes;
 }

tpws/params.h

@@ -18,6 +18,8 @@
 #define HOSTLIST_AUTO_FAIL_THRESHOLD_DEFAULT	3
 #define	HOSTLIST_AUTO_FAIL_TIME_DEFAULT 	60
 
+#define FIX_SEG_DEFAULT_MAX_WAIT		30
+
 enum bindll { unwanted=0, no, prefer, force };
 
 #define MAX_BINDS	32
@@ -102,13 +104,13 @@ struct params_s
 	char connect_bind6_ifname[IF_NAMESIZE];
 
 	uint8_t proxy_type;
+	unsigned int fix_seg;
 	bool no_resolve;
 	bool skip_nodelay;
-	bool fix_seg;
 	bool droproot;
+	bool daemon;
 	uid_t uid;
 	gid_t gid;
-	bool daemon;
 	char pidfile[256];
 	int maxconn,resolver_threads,maxfiles,max_orphan_time;
 	int local_rcvbuf,local_sndbuf,remote_rcvbuf,remote_sndbuf;

tpws/tpws.c

@@ -171,7 +171,7 @@ static void exithelp(void)
 		" --enable-pf\t\t\t\t; enable PF redirector support. required in FreeBSD when used with PF firewall.\n"
 #endif
 #if defined(__linux__)
-		" --fix-seg\t\t\t\t; fix segmentation failures at the cost of possible slowdown\n"
+		" --fix-seg=<int>\t\t\t; fix segmentation failures at the cost of possible slowdown. wait up to N msec (default %u)\n"
 #endif
 		" --debug=0|1|2|syslog|@<filename>\t; 1 and 2 means log to console and set debug level. for other targets use --debug-level.\n"
 		" --debug-level=0|1|2\t\t\t; specify debug level\n"
@@ -218,6 +218,9 @@ static void exithelp(void)
 		" --tamper-cutoff=[n]<pos>\t\t; do not tamper anymore after specified outbound stream position. default is unlimited.\n",
 #if defined(__linux__) || defined(__APPLE__)
 		DEFAULT_TCP_USER_TIMEOUT_LOCAL,DEFAULT_TCP_USER_TIMEOUT_REMOTE,
+#endif
+#ifdef __linux__
+		FIX_SEG_DEFAULT_MAX_WAIT,
 #endif
 		HOSTLIST_AUTO_FAIL_THRESHOLD_DEFAULT, HOSTLIST_AUTO_FAIL_TIME_DEFAULT
 	);
@@ -638,7 +641,7 @@ void parse_params(int argc, char *argv[])
 		{ "local-tcp-user-timeout",required_argument,0,0 },	// optidx=62
 		{ "remote-tcp-user-timeout",required_argument,0,0 },	// optidx=63
 		{ "mss",required_argument,0,0 },			// optidx=64
-		{ "fix-seg",no_argument,0,0 },				// optidx=65
+		{ "fix-seg",optional_argument,0,0 },			// optidx=65
 #ifdef SPLICE_PRESENT
 		{ "nosplice",no_argument,0,0 },				// optidx=66
 #endif
@@ -1233,7 +1236,18 @@ void parse_params(int argc, char *argv[])
 			}
 			break;
 		case 65: /* fix-seg */
-			params.fix_seg = true;
+			if (optarg)
+			{
+				i = atoi(optarg);
+				if (i < 0 || i > 1000)
+				{
+					DLOG_ERR("fix_seg value must be within 0..1000\n");
+					exit_clean(1);
+				}
+				params.fix_seg = i;
+			}
+			else
+				params.fix_seg = FIX_SEG_DEFAULT_MAX_WAIT;
 			break;
 #ifdef SPLICE_PRESENT
 		case 66: /* nosplice */

tpws/tpws_conn.c

@@ -1231,27 +1231,15 @@ static bool handle_epoll(tproxy_conn_t *conn, struct tailhead *conn_list, uint32
 						bApplyDisorder = !(i & 1) && i<multisplit_count && (split_flags & SPLIT_FLAG_DISORDER);
 						bApplyOOB = i==0 && (split_flags & SPLIT_FLAG_OOB);
 						len = to-from;
-						VPRINT("Sending multisplit part %d %zd-%zd (len %zd)%s%s : ", i+1, from, to, len, bApplyDisorder ? " with disorder" : "", bApplyOOB ? " with OOB" : "");
-						packet_debug(buf+from,len);
-						wr = send_oob(conn->partner->fd, buf+from, len, bApplyDisorder, bApplyOOB, conn->track.dp ? conn->track.dp->oob_byte : 0);
-						if (wr<0) break;
-						conn->partner->twr += wr;
-						if (wr<len)
-						{
-							from+=wr;
-							VPRINT("Cannot send part %d immediately. only %zd bytes were sent (%zd left in segment). cancelling split.\n", i+1, wr, bs-from);
-							wr = send_or_buffer(conn->partner->wr_buf, conn->partner->fd, buf+from, bs-from, 0, 0);
-							if (wr>0) conn->partner->twr += wr;
-							break;
-						}
 #ifdef __linux__
 						if (params.fix_seg)
 						{
 							unsigned int wasted;
-							if (!socket_wait_notsent(conn->partner->fd, 20, &wasted))
-								DLOG_ERR("WARNING ! segmentation failed\n");
+							bool bWaitOK = socket_wait_notsent(conn->partner->fd, params.fix_seg, &wasted);
 							if (wasted)
 								VPRINT("WARNING ! wasted %u ms to fix segmenation\n", wasted);
+							if (!bWaitOK)
+								DLOG_ERR("WARNING ! segmentation failed\n");
 						}
 						else
 						{
@@ -1259,6 +1247,19 @@ static bool handle_epoll(tproxy_conn_t *conn, struct tailhead *conn_list, uint32
 								DLOG_ERR("WARNING ! segmentation failed\n");
 						}
 #endif
+						VPRINT("Sending multisplit part %d %zd-%zd (len %zd)%s%s : ", i+1, from, to, len, bApplyDisorder ? " with disorder" : "", bApplyOOB ? " with OOB" : "");
+						packet_debug(buf+from,len);
+						wr = send_oob(conn->partner->fd, buf+from, len, bApplyDisorder, bApplyOOB, conn->track.dp ? conn->track.dp->oob_byte : 0);
+						if (wr<0) break;
+						conn->partner->twr += wr;
+						if (wr<len)
+						{
+							from+=wr;
+							VPRINT("Cannot send part %d immediately. only %zd bytes were sent (%zd left in segment). cancelling split.\n", i+1, wr, bs-from);
+							wr = send_or_buffer(conn->partner->wr_buf, conn->partner->fd, buf+from, bs-from, 0, 0);
+							if (wr>0) conn->partner->twr += wr;
+							break;
+						}
 						from = to;
 					}
 				}