static void log_option(Telnet telnet, char *sender, int cmd, int option)
{
char *buf;
/*
* The strange-looking "<?""?>" below is there to avoid a
* trigraph - a double question mark followed by > maps to a
* closing brace character!
*/
buf = dupprintf("%s:\t%s %s", sender,
(cmd == WILL ? "WILL" : cmd == WONT ? "WONT" :
cmd == DO ? "DO" : cmd == DONT ? "DONT" : "<?""?>"),
telopt(option));
logevent(telnet->frontend, buf);
sfree(buf);
}
void term_init()
{
tel_init();
telopt(1, WILL, TELOPT_SGA);
telopt(1, DO, TELOPT_SGA);
telopt(1, WILL, TELOPT_BINARY);
telopt(1, DO, TELOPT_BINARY);
telopt(1, WILL, TELOPT_ECHO);
telopt(1, DO, TELOPT_WINCH);
}
static void process_subneg(Telnet telnet)
{
unsigned char b[2048], *p, *q;
int var, value, n;
char *e;
switch (telnet->sb_opt) {
case TELOPT_TSPEED:
if (telnet->sb_len == 1 && telnet->sb_buf[0] == TELQUAL_SEND) {
char *logbuf;
b[0] = IAC;
b[1] = SB;
b[2] = TELOPT_TSPEED;
b[3] = TELQUAL_IS;
strcpy((char *)(b + 4), telnet->cfg.termspeed);
n = 4 + strlen(telnet->cfg.termspeed);
b[n] = IAC;
b[n + 1] = SE;
telnet->bufsize = sk_write(telnet->s, (char *)b, n + 2);
logevent(telnet->frontend, "server:\tSB TSPEED SEND");
logbuf = dupprintf("client:\tSB TSPEED IS %s", telnet->cfg.termspeed);
logevent(telnet->frontend, logbuf);
sfree(logbuf);
} else
logevent(telnet->frontend, "server:\tSB TSPEED <something weird>");
break;
case TELOPT_TTYPE:
if (telnet->sb_len == 1 && telnet->sb_buf[0] == TELQUAL_SEND) {
char *logbuf;
b[0] = IAC;
b[1] = SB;
b[2] = TELOPT_TTYPE;
b[3] = TELQUAL_IS;
for (n = 0; telnet->cfg.termtype[n]; n++)
b[n + 4] = (telnet->cfg.termtype[n] >= 'a'
&& telnet->cfg.termtype[n] <=
'z' ? telnet->cfg.termtype[n] + 'A' -
'a' : telnet->cfg.termtype[n]);
b[n + 4] = IAC;
b[n + 5] = SE;
telnet->bufsize = sk_write(telnet->s, (char *)b, n + 6);
b[n + 4] = 0;
logevent(telnet->frontend, "server:\tSB TTYPE SEND");
logbuf = dupprintf("client:\tSB TTYPE IS %s", b + 4);
logevent(telnet->frontend, logbuf);
sfree(logbuf);
} else
logevent(telnet->frontend, "server:\tSB TTYPE <something weird>\r\n");
break;
case TELOPT_OLD_ENVIRON:
case TELOPT_NEW_ENVIRON:
p = telnet->sb_buf;
q = p + telnet->sb_len;
if (p < q && *p == TELQUAL_SEND) {
char *logbuf;
p++;
logbuf = dupprintf("server:\tSB %s SEND", telopt(telnet->sb_opt));
logevent(telnet->frontend, logbuf);
sfree(logbuf);
if (telnet->sb_opt == TELOPT_OLD_ENVIRON) {
if (telnet->cfg.rfc_environ) {
value = RFC_VALUE;
var = RFC_VAR;
} else {
value = BSD_VALUE;
var = BSD_VAR;
}
/*
* Try to guess the sense of VAR and VALUE.
*/
while (p < q) {
if (*p == RFC_VAR) {
value = RFC_VALUE;
var = RFC_VAR;
} else if (*p == BSD_VAR) {
value = BSD_VALUE;
var = BSD_VAR;
}
p++;
}
} else {
/*
* With NEW_ENVIRON, the sense of VAR and VALUE
* isn't in doubt.
*/
value = RFC_VALUE;
var = RFC_VAR;
}
b[0] = IAC;
b[1] = SB;
b[2] = telnet->sb_opt;
b[3] = TELQUAL_IS;
n = 4;
e = telnet->cfg.environmt;
while (*e) {
b[n++] = var;
while (*e && *e != '\t')
b[n++] = *e++;
if (*e == '\t')
e++;
b[n++] = value;
while (*e)
b[n++] = *e++;
e++;
}
if (*telnet->cfg.username) {
b[n++] = var;
b[n++] = 'U';
b[n++] = 'S';
b[n++] = 'E';
b[n++] = 'R';
b[n++] = value;
e = telnet->cfg.username;
while (*e)
b[n++] = *e++;
}
b[n++] = IAC;
b[n++] = SE;
telnet->bufsize = sk_write(telnet->s, (char *)b, n);
logbuf = dupprintf("client:\tSB %s IS %s%s%s%s",
telopt(telnet->sb_opt),
*telnet->cfg.username ? "USER="******"",
telnet->cfg.username,
*telnet->cfg.username ? " " : "",
n == 6 ? "<nothing>" :
(*telnet->cfg.environmt ? "<stuff>" : ""));
logevent(telnet->frontend, logbuf);
sfree(logbuf);
}
break;
}
}
static void handlenetinput(int len)
{
int i;
int cstart = 0;
for (i = 0; i < len; i++)
{
byte c = G.buf[i];
if (G.telstate == 0) /* most of the time state == 0 */
{
if (c == IAC)
{
cstart = i;
G.telstate = TS_IAC;
}
}
else
switch (G.telstate)
{
case TS_0:
if (c == IAC)
G.telstate = TS_IAC;
else
G.buf[cstart++] = c;
break;
case TS_IAC:
if (c == IAC) /* IAC IAC -> 0xFF */
{
G.buf[cstart++] = c;
G.telstate = TS_0;
break;
}
/* else */
switch (c)
{
case SB:
G.telstate = TS_SUB1;
break;
case DO:
case DONT:
case WILL:
case WONT:
G.telwish = c;
G.telstate = TS_OPT;
break;
default:
G.telstate = TS_0; /* DATA MARK must be added later */
}
break;
case TS_OPT: /* WILL, WONT, DO, DONT */
telopt(c);
G.telstate = TS_0;
break;
case TS_SUB1: /* Subnegotiation */
case TS_SUB2: /* Subnegotiation */
if (subneg(c))
G.telstate = TS_0;
break;
}
}
if (G.telstate)
{
if (G.iaclen) iacflush();
if (G.telstate == TS_0) G.telstate = 0;
len = cstart;
}
if (len)
write(1, G.buf, len);
}
static void handle_net_input(int len)
{
int i;
int cstart = 0;
for (i = 0; i < len; i++) {
byte c = G.buf[i];
if (G.telstate == TS_NORMAL) { /* most typical state */
if (c == IAC) {
cstart = i;
G.telstate = TS_IAC;
}
else if (c == '\r') {
cstart = i + 1;
G.telstate = TS_CR;
}
/* No IACs were seen so far, no need to copy
* bytes within G.buf: */
continue;
}
switch (G.telstate) {
case TS_CR:
/* Prev char was CR. If cur one is NUL, ignore it.
* See RFC 1123 section 3.3.1 for discussion of telnet EOL handling.
*/
G.telstate = TS_COPY;
if (c == '\0')
break;
/* else: fall through - need to handle CR IAC ... properly */
case TS_COPY: /* Prev char was ordinary */
/* Similar to NORMAL, but in TS_COPY we need to copy bytes */
if (c == IAC)
G.telstate = TS_IAC;
else
G.buf[cstart++] = c;
if (c == '\r')
G.telstate = TS_CR;
break;
case TS_IAC: /* Prev char was IAC */
if (c == IAC) { /* IAC IAC -> one IAC */
G.buf[cstart++] = c;
G.telstate = TS_COPY;
break;
}
/* else */
switch (c) {
case SB:
G.telstate = TS_SUB1;
break;
case DO:
case DONT:
case WILL:
case WONT:
G.telwish = c;
G.telstate = TS_OPT;
break;
/* DATA MARK must be added later */
default:
G.telstate = TS_COPY;
}
break;
case TS_OPT: /* Prev chars were IAC WILL/WONT/DO/DONT */
telopt(c);
G.telstate = TS_COPY;
break;
case TS_SUB1: /* Subnegotiation */
case TS_SUB2: /* Subnegotiation */
subneg(c); /* can change G.telstate */
break;
}
}
if (G.telstate != TS_NORMAL) {
/* We had some IACs, or CR */
if (G.iaclen)
iac_flush();
if (G.telstate == TS_COPY) /* we aren't in the middle of IAC */
G.telstate = TS_NORMAL;
len = cstart;
}
if (len)
full_write(STDOUT_FILENO, G.buf, len);
}
