-#ifdef TCP_FASTOPEN
-static void
-tfo_out_check(int sock)
-{
-# if defined(TCP_INFO) && defined(EXIM_HAVE_TCPI_UNACKED)
-struct tcp_info tinfo;
-socklen_t len = sizeof(tinfo);
-
-if (getsockopt(sock, IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
- {
- /* This is a somewhat dubious detection method; totally undocumented so likely
- to fail in future kernels. There seems to be no documented way. */
-
- if (tinfo.tcpi_unacked > 1)
- {
- DEBUG(D_transport|D_v) debug_printf("TCP_FASTOPEN mode connection\n");
- tcp_out_fastopen = TRUE;
- }
- }
-# endif
-}
-#endif
+/* Arguments as for smtp_connect(), plus
+ early_data if non-NULL, data to be sent - preferably in the TCP SYN segment
+Returns: connected socket number, or -1 with errno set
+*/
int
smtp_sock_connect(host_item * host, int host_af, int port, uschar * interface,
- transport_instance * tb, int timeout)
+ transport_instance * tb, int timeout, const blob * early_data)
{
smtp_transport_options_block * ob =
(smtp_transport_options_block *)tb->options_block;
int dscp_option;
int sock;
int save_errno = 0;
-BOOL fastopen = FALSE;
#ifndef DISABLE_EVENT
deliver_host_address = host->address;
(void) setsockopt(sock, dscp_level, dscp_option, &dscp_value, sizeof(dscp_value));
}
-#ifdef TCP_FASTOPEN
-if (verify_check_given_host (&ob->hosts_try_fastopen, host) == OK) fastopen = TRUE;
-#endif
-
/* Bind to a specific interface if requested. Caller must ensure the interface
is the same type (IPv4 or IPv6) as the outgoing address. */
}
/* Connect to the remote host, and add keepalive to the socket before returning
-it, if requested. */
+it, if requested. If the build supports TFO, request it - and if the caller
+requested some early-data then include that in the TFO request. */
-else if (ip_connect(sock, host_af, host->address, port, timeout, fastopen) < 0)
- save_errno = errno;
+else
+ {
+ const blob * fastopen = NULL;
+
+#ifdef TCP_FASTOPEN
+ if (verify_check_given_host(&ob->hosts_try_fastopen, host) == OK)
+ fastopen = early_data ? early_data : &tcp_fastopen_nodata;
+#endif
+
+ if (ip_connect(sock, host_af, host->address, port, timeout, fastopen) < 0)
+ save_errno = errno;
+ else if (early_data && !fastopen && early_data->data && early_data->len)
+ if (send(sock, early_data->data, early_data->len, 0) < 0)
+ save_errno = errno;
+ }
/* Either bind() or connect() failed */
return -1;
}
if (ob->keepalive) ip_keepalive(sock, host->address, TRUE);
-#ifdef TCP_FASTOPEN
- tfo_out_check(sock);
-#endif
return sock;
}
}
return socks_sock_connect(host, host_af, port, interface, tb, timeout);
#endif
-return smtp_sock_connect(host, host_af, port, interface, tb, timeout);
+return smtp_sock_connect(host, host_af, port, interface, tb, timeout, NULL);
}