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telnetd: correctly output 0xff char. ~100 bytes.

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telnet: fix some atrocious names and style. no code changes
This commit is contained in:
Denis Vlasenko
2008-11-11 02:56:39 +00:00
parent e9b9a19ad3
commit 9f2f808b0d
2 changed files with 169 additions and 123 deletions
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58
networking/telnetd.c
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@@ -74,9 +74,6 @@ static const char *issuefile = "/etc/issue.net";
past (bf + len) then that IAC will be left unprocessed and *processed
will be less than len.
FIXME - if we mean to send 0xFF to the terminal then it will be escaped,
what is the escape character? We aren't handling that situation here.
CR-LF ->'s CR mapping is also done here, for convenience.
NB: may fail to remove iacs which wrap around buffer!
@@ -159,6 +156,47 @@ remove_iacs(struct tsession *ts, int *pnum_totty)
return memmove(ptr - num_totty, ptr0, num_totty);
}
/*
* Converting single 0xff into double on output
*/
static size_t iac_safe_write(int fd, const char *buf, size_t count)
{
const char *oxff;
size_t wr, rc, total;
total = 0;
while (1) {
if (count == 0)
return total;
if (*buf == (char)0xff) {
rc = safe_write(fd, "\xff\xff", 2);
if (rc != 2)
break;
buf++;
total++;
count--;
continue;
}
/* count != 0, *buf != 0xff */
oxff = memchr(buf, 0xff, count);
wr = count;
if (oxff)
wr = oxff - buf;
rc = safe_write(fd, buf, wr);
if (rc != wr)
break;
buf += rc;
total += rc;
count -= rc;
}
/* here: rc - result of last short write */
if ((ssize_t)rc < 0) { /* error? */
if (total == 0)
return rc;
rc = 0;
}
return total + rc;
}
static struct tsession *
make_new_session(
@@ -212,9 +250,15 @@ make_new_session(
IAC, WILL, TELOPT_ECHO,
IAC, WILL, TELOPT_SGA
};
memcpy(TS_BUF2, iacs_to_send, sizeof(iacs_to_send));
ts->rdidx2 = sizeof(iacs_to_send);
ts->size2 = sizeof(iacs_to_send);
/* This confuses iac_safe_write(), it will try to duplicate
* each IAC... */
//memcpy(TS_BUF2, iacs_to_send, sizeof(iacs_to_send));
//ts->rdidx2 = sizeof(iacs_to_send);
//ts->size2 = sizeof(iacs_to_send);
/* So just stuff it into TCP buffer! */
safe_write(sock, iacs_to_send, sizeof(iacs_to_send));
/*ts->rdidx2 = 0; - xzalloc did it! */
/*ts->size2 = 0;*/
}
fflush(NULL); /* flush all streams */
@@ -538,7 +582,7 @@ int telnetd_main(int argc UNUSED_PARAM, char **argv)
if (/*ts->size2 &&*/ FD_ISSET(ts->sockfd_write, &wrfdset)) {
/* Write to socket from buffer 2. */
count = MIN(BUFSIZE - ts->wridx2, ts->size2);
count = safe_write(ts->sockfd_write, TS_BUF2 + ts->wridx2, count);
count = iac_safe_write(ts->sockfd_write, (void*)(TS_BUF2 + ts->wridx2), count);
if (count < 0) {
if (errno == EAGAIN)
goto skip2;