* Exim - an Internet mail transport agent *
*************************************************/
+/* Copyright (c) The Exim Maintainers 2020 - 2023 */
/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Functions for doing things with sockets. With the advent of IPv6 this has
got messier, so that it's worth pulling out the code into separate functions
#include "exim.h"
+#if defined(TCP_FASTOPEN)
+# if defined(MSG_FASTOPEN) || defined(EXIM_TFO_CONNECTX) || defined(EXIM_TFO_FREEBSD)
+# define EXIM_SUPPORT_TFO
+# endif
+#endif
+
/*************************************************
* Create a socket *
*************************************************/
return sizeof(sin->v6);
}
else
-#else /* HAVE_IPv6 */
-af = af; /* Avoid compiler warning */
#endif /* HAVE_IPV6 */
/* Setup code when using IPv4 socket. The wildcard address is "". */
{
union sockaddr_46 sin;
int s_len = ip_addr(&sin, af, address, port);
-return bind(sock, (struct sockaddr *)&sin, s_len);
+int rc = bind(sock, (struct sockaddr *)&sin, s_len);
+if (rc < 0)
+ log_write(0, LOG_MAIN, "bind of [%s]:%d failed", address, port);
+return rc;
}
-/*************************************************
-*************************************************/
-
-#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))
- )
- f.tcp_fastopen_ok = TRUE;
-close(sock);
-# endif
-}
-#endif
-
-
/*************************************************
* Connect socket to remote host *
*************************************************/
s_len = sizeof(s_in6);
}
else
-#else /* HAVE_IPV6 */
-af = af; /* Avoid compiler warning */
#endif /* HAVE_IPV6 */
/* For an IPv4 address, use an IPv4 sockaddr structure, even on a system with
sigalrm_seen = FALSE;
if (timeout > 0) ALARM(timeout);
-#ifdef TCP_FASTOPEN
+#ifdef EXIM_SUPPORT_TFO
/* TCP Fast Open, if the system has a cookie from a previous call to
this peer, can send data in the SYN packet. The peer can send data
before it gets our ACK of its SYN,ACK - the latter is useful for
if (fastopen_blob && f.tcp_fastopen_ok)
{
# ifdef MSG_FASTOPEN
- /* This is a Linux implementation. It might be useable on FreeBSD; I have
- not checked. */
+ /* This is a Linux implementation. */
if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len,
MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0)
/*XXX also seen on successful TFO, sigh */
tcp_out_fastopen = fastopen_blob->len > 0 ? TFO_ATTEMPTED_DATA : TFO_ATTEMPTED_NODATA;
}
- else if (errno == EINPROGRESS) /* expected if we had no cookie for peer */
+ else switch (errno)
+ {
+ case 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 */
- 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 = TFO_ATTEMPTED_NODATA; /* we tried; unknown if useful yet */
- rc = 0;
- }
- else
- rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0);
+ 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 = TFO_ATTEMPTED_NODATA; /* we tried; unknown if useful yet */
+ rc = 0;
+ }
+ else /* queue unsent data */
+ rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0);
+ break;
+
+ case EOPNOTSUPP:
+ DEBUG(D_transport)
+ debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n");
+ goto legacy_connect;
+
+ case EPIPE:
+ DEBUG(D_transport)
+ debug_printf("Tried TCP Fast Open but kernel too old to support it\n");
+ goto legacy_connect;
}
- else if(errno == EOPNOTSUPP)
+
+# elif defined(EXIM_TFO_FREEBSD)
+ /* Re: https://people.freebsd.org/~pkelsey/tfo-tools/tfo-client.c */
+
+ if (setsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &on, sizeof(on)) < 0)
{
DEBUG(D_transport)
debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n");
goto legacy_connect;
}
-# endif
-# ifdef EXIM_TFO_CONNECTX
+ if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len, 0,
+ s_ptr, s_len)) >= 0)
+ {
+ DEBUG(D_transport|D_v)
+ debug_printf(" TFO mode connection attempt to %s, %lu data\n",
+ address, (unsigned long)fastopen_blob->len);
+ tcp_out_fastopen = fastopen_blob->len > 0 ? TFO_ATTEMPTED_DATA : TFO_ATTEMPTED_NODATA;
+ }
+
+# elif defined(EXIM_TFO_CONNECTX)
/* MacOS */
sa_endpoints_t ends = {
.sae_srcif = 0, .sae_srcaddr = NULL, .sae_srcaddrlen = 0,
# endif
}
else
-#endif /*TCP_FASTOPEN*/
+#endif /*EXIM_SUPPORT_TFO*/
{
-#if defined(TCP_FASTOPEN) && defined(MSG_FASTOPEN)
+#if defined(EXIM_SUPPORT_TFO) && !defined(EXIM_TFO_CONNECTX)
legacy_connect:
#endif
for (int port = portlo; port <= porthi; port++)
if (ip_connect(fd, af, h->address, port, timeout, fastopen_blob) == 0)
{
- if (fd != fd6) close(fd6);
- if (fd != fd4) close(fd4);
+ if (fd6 >= 0 && fd != fd6) close(fd6);
+ if (fd4 >= 0 && fd != fd4) close(fd4);
if (connhost)
{
h->port = port;
/*XXX TFO? */
int
-ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo)
+ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo,
+ host_item * connhost)
{
int scan;
uschar hostname[256];
}
return ip_connectedsocket(SOCK_STREAM, hostname, portlow, porthigh,
- tmo, NULL, errstr, NULL);
+ tmo, connhost, errstr, NULL);
}
int
return sock;
}
+/* spec is either an absolute path (with a leading /), or
+a host (name or IP) and port (whitespace-separated).
+The port can be a range, dash-separated, or a single number.
+
+For a TCP socket, optionally fill in a host_item.
+*/
int
-ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo)
+ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo,
+ host_item * connhost)
{
return *spec == '/'
- ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo);
+ ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo, connhost);
}
/*************************************************
BOOL
fd_ready(int fd, time_t timelimit)
{
-fd_set select_inset;
-int time_left = timelimit - time(NULL);
-int rc;
+int rc, time_left = timelimit - time(NULL);
if (time_left <= 0)
{
do
{
- struct timeval tv = { .tv_sec = time_left, .tv_usec = 0 };
- FD_ZERO (&select_inset);
- FD_SET (fd, &select_inset);
-
/*DEBUG(D_transport) debug_printf("waiting for data on fd\n");*/
- rc = select(fd + 1, (SELECT_ARG2_TYPE *)&select_inset, NULL, NULL, &tv);
+ rc = poll_one_fd(fd, POLLIN, time_left * 1000);
/* If some interrupt arrived, just retry. We presume this to be rare,
but it can happen (e.g. the SIGUSR1 signal sent by exiwhat causes
/* Checking the FD_ISSET is not enough, if we're interrupted, the
select_inset may still contain the 'input'. */
}
-while (rc < 0 || !FD_ISSET(fd, &select_inset));
+while (rc < 0);
return TRUE;
}
git://git.exim.org / exim.git / blobdiff