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ssh: actually handle flow control and channel id's

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This commit is contained in:
cinap_lenrek 2017-04-21 19:23:56 +02:00
parent 99825e22ed
commit a944c37d68
1 changed files with 61 additions and 20 deletions
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81
sys/src/cmd/ssh.c
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@ -45,19 +45,33 @@ enum {
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 @@ dispatch(void)
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 @@ dispatch(void)
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 @@ usage(void)
void
main(int argc, char *argv[])
{
static char buf[8*1024];
static QLock sl;
int b, n, c;
char *s;
@ -1106,6 +1132,8 @@ main(int argc, char *argv[])
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 @@ Next0: switch(recvpkt()){
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 @@ Next1: switch(recvpkt()){
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 @@ Next1: switch(recvpkt()){
if(raw) {
rawon();
sendpkt("busbsuuuus", MSG_CHANNEL_REQUEST,
0,
send.chan,
"pty-req", 7,
0,
tty.term, strlen(tty.term),
@ -1182,26 +1219,27 @@ Next1: switch(recvpkt()){
}
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;
if(n < 0 && wasintr()){
if(!raw) break;
sendpkt("busbs", MSG_CHANNEL_REQUEST,
0,
send.chan,
"signal", 6,
0,
"INT", 3);
@ -1210,12 +1248,15 @@ Next1: switch(recvpkt()){
}
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);