+/*************************************************
+*************************************************/
+
+#ifdef EXIM_TFO_PROBE
+void
+tfo_probe(void)
+{
+# ifdef TCP_FASTOPEN
+int sock, backlog = 5;
+
+if ( (sock = socket(SOCK_STREAM, AF_INET, 0)) < 0
+ && setsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &backlog, sizeof(backlog))
+ )
+ tcp_fastopen_ok = TRUE;
+close(sock);
+# endif
+}
+#endif
+
+
/*************************************************
* Connect socket to remote host *
*************************************************/
address the remote address, in text form
port the remote port
timeout a timeout (zero for indefinite timeout)
- fastopen non-null iff TCP_FASTOPEN can be used; may indicate early-data to
+ fastopen_blob non-null iff TCP_FASTOPEN can be used; may indicate early-data to
be sent in SYN segment
Returns: 0 on success; -1 on failure, with errno set
int
ip_connect(int sock, int af, const uschar *address, int port, int timeout,
- const blob * fastopen)
+ const blob * fastopen_blob)
{
struct sockaddr_in s_in4;
struct sockaddr *s_ptr;
the SMTP banner. Other (than SMTP) cases of TCP connections can
possibly use the data-on-syn, so support that too. */
-if (fastopen)
+if (fastopen_blob && tcp_fastopen_ok)
{
- if ((rc = sendto(sock, fastopen->data, fastopen->len,
+ if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len,
MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0)
/* seen for with-data, experimental TFO option, with-cookie case */
+ /* seen for with-data, proper TFO opt, with-cookie case */
{
- DEBUG(D_transport|D_v) debug_printf("TFO mode connection attempt, %s data\n",
- fastopen->len > 0 ? "with" : "no");
- tcp_out_fastopen = fastopen->len > 0 ? 2 : 1;
+ DEBUG(D_transport|D_v)
+ debug_printf("non-TFO mode connection attempt to %s, %lu data\n",
+ address, (unsigned long)fastopen_blob->len);
+ tcp_out_fastopen = fastopen_blob->len > 0 ? 2 : 1;
}
- else if (errno == EINPROGRESS) /* expected for nonready peer */
+ else if (errno == EINPROGRESS) /* expected if we had no cookie for peer */
/* seen for no-data, proper TFO option, both cookie-request and with-cookie cases */
/* apparently no visibility of the diffference at this point */
+ /* seen for with-data, proper TFO opt, cookie-req */
/* with netwk delay, post-conn tcp_info sees unacked 1 for R, 2 for C; code in smtp_out.c */
/* ? older Experimental TFO option behaviour ? */
{ /* queue unsent data */
- if (!fastopen->data)
+ DEBUG(D_transport|D_v) debug_printf("TFO mode sendto, %s data: EINPROGRESS\n",
+ fastopen_blob->len > 0 ? "with" : "no");
+ if (!fastopen_blob->data)
{
- tcp_out_fastopen = 1; /* we tried; unknown if useful yet */
+ tcp_out_fastopen = 1; /* we tried; unknown if useful yet */
rc = 0;
}
- else if ( (rc = send(sock, fastopen->data, fastopen->len, 0)) < 0
- && errno == EINPROGRESS /* expected for nonready peer */
- )
- rc = 0;
+ else
+ rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0);
}
else if(errno == EOPNOTSUPP)
{
#endif
{
legacy_connect:
+ DEBUG(D_transport|D_v) if (fastopen_blob)
+ debug_printf("non-TFO mode connection attempt to %s, %lu data\n",
+ address, (unsigned long)fastopen_blob->len);
if ((rc = connect(sock, s_ptr, s_len)) >= 0)
- if ( fastopen && fastopen->data && fastopen->len
- && send(sock, fastopen->data, fastopen->len, 0) < 0)
+ if ( fastopen_blob && fastopen_blob->data && fastopen_blob->len
+ && send(sock, fastopen_blob->data, fastopen_blob->len, 0) < 0)
rc = -1;
}
timeout a timeout
connhost if not NULL, host_item to be filled in with connection details
errstr pointer for allocated string on error
- fastopen with SOCK_STREAM, if non-null, request TCP Fast Open.
+ fastopen_blob with SOCK_STREAM, if non-null, request TCP Fast Open.
Additionally, optional early-data to send
Return:
*/
int
ip_connectedsocket(int type, const uschar * hostname, int portlo, int porthi,
- int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen)
+ int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen_blob)
{
int namelen, port;
host_item shost;
}
for(port = portlo; port <= porthi; port++)
- if (ip_connect(fd, af, h->address, port, timeout, fastopen) == 0)
+ if (ip_connect(fd, af, h->address, port, timeout, fastopen_blob) == 0)
{
if (fd != fd6) close(fd6);
if (fd != fd4) close(fd4);