static void
conread(int s)
{
con *c = &fdcon[s];
size_t n;
if (c->c_status == CS_CON) {
congreet(s);
return;
}
n = atomicio(read, s, c->c_data + c->c_off, c->c_len - c->c_off);
if (n == 0) {
error("read (%s): %s", c->c_name, strerror(errno));
confree(s);
return;
}
c->c_off += n;
if (c->c_off == c->c_len)
switch (c->c_status) {
case CS_SIZE:
c->c_plen = htonl(c->c_plen);
c->c_len = c->c_plen + 8 - (c->c_plen & 7);
c->c_off = 0;
c->c_data = xmalloc(c->c_len);
c->c_status = CS_KEYS;
break;
default:
fatal("conread: invalid status %d", c->c_status);
break;
}
contouch(s);
}
static void
congreet(int s)
{
int n = 0, remote_major = 0, remote_minor = 0;
char buf[256], *cp;
char remote_version[sizeof buf];
size_t bufsiz;
con *c = &fdcon[s];
for (;;) {
memset(buf, '\0', sizeof(buf));
bufsiz = sizeof(buf);
cp = buf;
while (bufsiz-- &&
(n = atomicio(read, s, cp, 1)) == 1 && *cp != '\n') {
if (*cp == '\r')
*cp = '\n';
cp++;
}
if (n != 1 || strncmp(buf, "SSH-", 4) == 0)
break;
}
if (n == 0) {
switch (errno) {
case EPIPE:
error("%s: Connection closed by remote host", c->c_name);
break;
case ECONNREFUSED:
break;
default:
error("read (%s): %s", c->c_name, strerror(errno));
break;
}
conrecycle(s);
return;
}
if (*cp != '\n' && *cp != '\r') {
error("%s: bad greeting", c->c_name);
confree(s);
return;
}
*cp = '\0';
if (sscanf(buf, "SSH-%d.%d-%[^\n]\n",
&remote_major, &remote_minor, remote_version) == 3)
compat_datafellows(remote_version);
else
datafellows = 0;
if (c->c_keytype != KT_RSA1) {
if (!ssh2_capable(remote_major, remote_minor)) {
debug("%s doesn't support ssh2", c->c_name);
confree(s);
return;
}
} else if (remote_major != 1) {
debug("%s doesn't support ssh1", c->c_name);
confree(s);
return;
}
fprintf(stderr, "# %s %s\n", c->c_name, chop(buf));
n = snprintf(buf, sizeof buf, "SSH-%d.%d-OpenSSH-keyscan\r\n",
c->c_keytype == KT_RSA1? PROTOCOL_MAJOR_1 : PROTOCOL_MAJOR_2,
c->c_keytype == KT_RSA1? PROTOCOL_MINOR_1 : PROTOCOL_MINOR_2);
if (n < 0 || (size_t)n >= sizeof(buf)) {
error("snprintf: buffer too small");
confree(s);
return;
}
if (atomicio(vwrite, s, buf, n) != (size_t)n) {
error("write (%s): %s", c->c_name, strerror(errno));
confree(s);
return;
}
if (c->c_keytype != KT_RSA1) {
keyprint(c, keygrab_ssh2(c));
confree(s);
return;
}
c->c_status = CS_SIZE;
contouch(s);
}
