shithub: riscv

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ssh: actually handle flow control and channel id's

--- a/sys/src/cmd/ssh.c

+++ b/sys/src/cmd/ssh.c

@@ -45,19 +45,33 @@

 	MSG_CHANNEL_FAILURE,

 };

+

+enum {

+	Overhead = 256,		// enougth for MSG_CHANNEL_DATA header

+	MaxPacket = 1<<15,

+	WinPackets = 8,		// (1<<15) * 8 = 256K

+};

+

 typedef struct

 {

-	int		pid;

 	u32int		seq;

 	u32int		kex;

+	u32int		chan;

+

+	int		win;

+	int		pkt;

+	int		eof;

+

 	Chachastate	cs1;

 	Chachastate	cs2;

-	char		*v;

-	char		eof;

 	uchar		*r;

 	uchar		*w;

-	uchar		b[1<<15];

+	uchar		b[Overhead + MaxPacket];

+

+	char		*v;

+	int		pid;

+	Rendez;

 } Oneway;

 int nsid;

@@ -902,7 +916,6 @@

 	switch(recv.r[0]){

 	case MSG_IGNORE:

 	case MSG_GLOBAL_REQUEST:

-	case MSG_CHANNEL_WINDOW_ADJUST:

 		return;

 	case MSG_DISCONNECT:

 		if(unpack(recv.r, recv.w-recv.r, "_us", &c, &s, &n) < 0)

@@ -922,24 +935,38 @@

 	case MSG_CHANNEL_DATA:

 		if(unpack(recv.r, recv.w-recv.r, "_us", &c, &s, &n) < 0)

 			break;

-		if(c != 0)

+		if(c != recv.chan)

 			break;

 		if(write(1, s, n) != n)

 			sysfatal("write out: %r");

 	Winadjust:

-		sendpkt("buu", MSG_CHANNEL_WINDOW_ADJUST, c, n);

+		recv.win -= n;

+		if(recv.win < recv.pkt){

+			n = WinPackets*recv.pkt;

+			recv.win += n;

+			sendpkt("buu", MSG_CHANNEL_WINDOW_ADJUST, send.chan, n);

+		}

 		return;

 	case MSG_CHANNEL_EXTENDED_DATA:

 		if(unpack(recv.r, recv.w-recv.r, "_uus", &c, &b, &s, &n) < 0)

 			break;

-		if(c != 0)

+		if(c != recv.chan)

 			break;

 		if(b == 1) write(2, s, n);

 		goto Winadjust;

+	case MSG_CHANNEL_WINDOW_ADJUST:

+		if(unpack(recv.r, recv.w-recv.r, "_uu", &c, &n) < 0)

+			break;

+		if(c != recv.chan)

+			break;

+		send.win += n;

+		if(send.win >= send.pkt)

+			rwakeup(&send);

+		return;

 	case MSG_CHANNEL_REQUEST:

 		if(unpack(recv.r, recv.w-recv.r, "_usb.", &c, &s, &n, &b, &p) < 0)

 			break;

-		if(c != 0)

+		if(c != recv.chan)

 			break;

 		if(n == 11 && memcmp(s, "exit-signal", n) == 0){

 			if(unpack(p, recv.w-p, "s", &s, &n) < 0)

@@ -1044,7 +1071,6 @@

 void

 main(int argc, char *argv[])

 {

-	static char buf[8*1024];

 	static QLock sl;

 	int b, n, c;

 	char *s;

@@ -1106,6 +1132,8 @@

 		sysfatal("bad server version: %s", recv.v);

 	recv.v = strdup(recv.v);

+	send.l = recv.l = &sl;

+

 	kex(0);

 	if(user == nil)

@@ -1124,12 +1152,16 @@

 	if(pubkeyauth() < 0 && passauth() < 0 && kbintauth() < 0)

 		sysfatal("auth: %r");

+	recv.pkt = MaxPacket;

+	recv.win = WinPackets*recv.pkt;

+	recv.chan = 0;

+

 	/* open hailing frequencies */

 	sendpkt("bsuuu", MSG_CHANNEL_OPEN,

 		"session", 7,

-		0,

-		8*sizeof(buf),

-		sizeof(buf));

+		recv.chan,

+		recv.win,

+		recv.pkt);

 Next1:	switch(recvpkt()){

 	default:

@@ -1143,6 +1175,11 @@

 		break;

 	}

+	if(unpack(recv.r, recv.w-recv.r, "_uuuu", &recv.chan, &send.chan, &send.win, &send.pkt) < 0)

+		sysfatal("bad channel open confirmation");

+	if(send.pkt <= 0 || send.pkt > MaxPacket)

+		send.pkt = MaxPacket;

+

 	notify(catch);

 	atexit(shutdown);

@@ -1170,7 +1207,7 @@

 	if(raw) {

 		rawon();

 		sendpkt("busbsuuuus", MSG_CHANNEL_REQUEST,

-			0,

+			send.chan,

 			"pty-req", 7,

 			0,

 			tty.term, strlen(tty.term),

@@ -1182,19 +1219,20 @@

 	}

 	if(cmd == nil){

 		sendpkt("busb", MSG_CHANNEL_REQUEST,

-			0,

+			send.chan,

 			"shell", 5,

 			0);

 	} else {

 		sendpkt("busbs", MSG_CHANNEL_REQUEST,

-			0,

+			send.chan,

 			"exec", 4,

 			0,

 			cmd, strlen(cmd));

 	}

 	for(;;){

+		static uchar buf[MaxPacket];

 		qunlock(&sl);

-		n = read(0, buf, sizeof(buf));

+		n = read(0, buf, send.pkt);

 		qlock(&sl);

 		if(send.eof)

 			break;

@@ -1201,7 +1239,7 @@

 		if(n < 0 && wasintr()){

 			if(!raw) break;

 			sendpkt("busbs", MSG_CHANNEL_REQUEST,

-				0,

+				send.chan,

 				"signal", 6,

 				0,

 				"INT", 3);

@@ -1210,12 +1248,15 @@

 		}

 		if(n <= 0)

 			break;

+		send.win -= n;

+		while(send.win < 0)

+			rsleep(&send);

 		sendpkt("bus", MSG_CHANNEL_DATA,

-			0,

+			send.chan,

 			buf, n);

 	}

 	if(send.eof++ == 0)

-		sendpkt("bu", raw ? MSG_CHANNEL_CLOSE : MSG_CHANNEL_EOF, 0);

+		sendpkt("bu", raw ? MSG_CHANNEL_CLOSE : MSG_CHANNEL_EOF, send.chan);

 	qunlock(&sl);

 	exits(nil);