8. A "noutf8" debug option, for disabling the UTF-8 characters in debug output.
+ 9. TCP Fast Open support on MacOS.
+
Version 4.91
--------------
#define _DARWIN_UNLIMITED_GETGROUPS
#define EXIM_GROUPLIST_SIZE 64
-/* TCP_FASTOPEN support. For the moment, claim there is none
-(the probe fails; unsure why).
-Sometime in the future need to investigate connectex(). */
-
-#define EXIM_TFO_PROBE
+/* TCP Fast Open: Darwin uses a connectex() call
+rather than a modified sendto() */
+#define EXIM_TFO_CONNECTX
/* End */
else
debug_printf("listening on %s port %d\n", ipa->address, ipa->port);
-#ifdef TCP_FASTOPEN
+#if defined(TCP_FASTOPEN) && !defined(__APPLE__)
if ( f.tcp_fastopen_ok
&& setsockopt(listen_sockets[sk], IPPROTO_TCP, TCP_FASTOPEN,
&smtp_connect_backlog, sizeof(smtp_connect_backlog)))
/* Start listening on the bound socket, establishing the maximum backlog of
connections that is allowed. On success, continue to the next address. */
- if (listen(listen_sockets[sk], smtp_connect_backlog) >= 0) continue;
+ if (listen(listen_sockets[sk], smtp_connect_backlog) >= 0)
+ {
+#if defined(TCP_FASTOPEN) && defined(__APPLE__)
+ if ( f.tcp_fastopen_ok
+ && setsockopt(listen_sockets[sk], IPPROTO_TCP, TCP_FASTOPEN,
+ &on, sizeof(on)))
+ {
+ DEBUG(D_any) debug_printf("setsockopt FASTOPEN: %s\n", strerror(errno));
+ f.tcp_fastopen_ok = FALSE;
+ }
+#endif
+ continue;
+ }
/* Listening has failed. In an IPv6 environment, as for bind(), if listen()
fails with the error EADDRINUSE and we are doing IPv4 wildcard listening
port = ntohs(service_info->s_port);
}
+ /*XXX we trust that the request is idempotent. Hmm. */
fd = ip_connectedsocket(SOCK_STREAM, server_name, port, port,
timeout, &host, &expand_string_message,
do_tls ? NULL : &reqstr);
port the remote port
timeout a timeout (zero for indefinite timeout)
fastopen_blob non-null iff TCP_FASTOPEN can be used; may indicate early-data to
- be sent in SYN segment
+ be sent in SYN segment. Any such data must be idempotent.
Returns: 0 on success; -1 on failure, with errno set
*/
sigalrm_seen = FALSE;
if (timeout > 0) ALARM(timeout);
-#if defined(TCP_FASTOPEN) && defined(MSG_FASTOPEN)
+#ifdef TCP_FASTOPEN
/* 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
the SMTP banner. Other (than SMTP) cases of TCP connections can
-possibly use the data-on-syn, so support that too.
-
-This is a Linux implementation. It might be useable on FreeBSD; I have
-not checked. I think MacOS has a "connectx" call for this purpose,
-rather than using "sendto" ? */
+possibly use the data-on-syn, so support that too. */
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. */
+
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 */
debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n");
goto legacy_connect;
}
+# endif
+# ifdef EXIM_TFO_CONNECTX
+ /* MacOS */
+ sa_endpoints_t ends = {
+ .sae_srcif = 0, .sae_srcaddr = NULL, .sae_srcaddrlen = 0,
+ .sae_dstaddr = s_ptr, .sae_dstaddrlen = s_len };
+ struct iovec iov = {
+ .iov_base = fastopen_blob->data, .iov_len = fastopen_blob->len };
+ size_t len;
+
+ if ((rc = connectx(sock, &ends, SAE_ASSOCID_ANY,
+ CONNECT_DATA_IDEMPOTENT, &iov, 1, &len, NULL)) == 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_USED : TFO_ATTEMPTED;
+
+ if (len != fastopen_blob->len)
+ DEBUG(D_transport|D_v)
+ debug_printf(" only queued %lu data!\n", (unsigned long)len);
+ }
+ else if (errno == EINPROGRESS)
+ {
+ 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; /* we tried; unknown if useful yet */
+ rc = 0;
+ }
+ else /* assume that no data was queued; block in send */
+ rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0);
+ }
+# endif
}
else
-#endif
+#endif /*TCP_FASTOPEN*/
{
legacy_connect:
DEBUG(D_transport|D_v) if (fastopen_blob)
connhost if not NULL, host_item to be filled in with connection details
errstr pointer for allocated string on error
fastopen_blob with SOCK_STREAM, if non-null, request TCP Fast Open.
- Additionally, optional early-data to send
+ Additionally, optional idempotent early-data to send
Return:
socket fd, or -1 on failure (having allocated an error string)
* on both connections (as one host could resolve to multiple ips) */
for (;;)
{
+ /*XXX we trust that the cmd_str is ideempotent */
if ((malware_daemon_ctx.sock = m_tcpsocket(cd->hostspec, cd->tcp_port,
&connhost, &errstr, &cmd_str)) >= 0)
{
/* Arguments as for smtp_connect(), plus
- early_data if non-NULL, data to be sent - preferably in the TCP SYN segment
+ early_data if non-NULL, idenmpotent data to be sent -
+ preferably in the TCP SYN segment
Returns: connected socket number, or -1 with errno set
*/
proxy.address = proxy.name = sob->proxy_host;
proxy_af = Ustrchr(sob->proxy_host, ':') ? AF_INET6 : AF_INET;
+ /*XXX we trust that the method-select command is idempotent */
if ((fd = smtp_sock_connect(&proxy, proxy_af, sob->port,
interface, tb, sob->timeout, &early_data)) >= 0)
{
early_data.data = buffer;
early_data.len = qlen;
+/*XXX we trust that the query is idempotent */
if (ip_connect(ident_conn_ctx.sock, host_af, sender_host_address, port,
rfc1413_query_timeout, &early_data) < 0)
{
# an unhelpful error from RTNETLINK.
# To tidy up: 'sudo tc qdisc delete dev lo root'
#
+# MacOS:
+# The kernel seems to have TFO enabled both ways as default.
+# There is a net.inet.tcp.clear_tfocache parameter
+## sysctl -w foo-val
+#
+# For network delays there is something called 'Network Link Conditioner'
+# which might do the job. But how to manipulate it?
+#
+#
sudo perl
system ("tc qdisc add dev lo root netem delay 50ms");
****
# (currently on a separate packet after the server SYN,ACK but before
# the client ACK).
#
-# The client log => lint.ex should have a "TFO" element.
-# Assuming this is the first run since boot, the a@test recipient will not.
+# The client log => line should have a "TFO" element.
+# The server log <= line for a@test.ex should not.
#
+# First clear any previously-obtained cookie:
sudo perl
system ("ip tcp_metrics delete 127.0.0.1");
****
#
-# The server log <= line for b@test.ex should have a "TFO" element, but
-# this will only be obtained when the above delay is inserted into the
-# loopback net path.
-#
#
#
# FreeBSD: it looks like you have to compile a custom kernel, with
****
sleep 3
#
+# The server log <= line for b@test.ex should have a "TFO" element, but
+# this will only be obtained when the above delay is inserted into the
+# loopback net path.
+#
exim b@test.ex
Testing
****
printf("IPv6 socket creation failed: %s\n", strerror(errno));
exit(1);
}
-#ifdef TCP_FASTOPEN
+#if defined(TCP_FASTOPEN) && !defined(__APPLE__)
if (tfo)
{
int backlog = 5;
printf("IPv4 socket creation failed: %s\n", strerror(errno));
exit(1);
}
-#ifdef TCP_FASTOPEN
+#if defined(TCP_FASTOPEN) && !defined(__APPLE__)
if (tfo)
{
int backlog = 5;
output anything, because it will mess up the test output, which will be
different for systems that do this and those that don't. */
-for (i = 0; i <= skn; i++)
+for (i = 0; i <= skn; i++) if (listen_socket[i] >= 0)
{
- if (listen_socket[i] >= 0 && listen(listen_socket[i], 5) < 0)
- {
+ if (listen(listen_socket[i], 5) < 0)
if (i != v4n || listen_socket[v6n] < 0 || errno != EADDRINUSE)
{
printf("listen() failed: %s\n", strerror(errno));
exit(1);
}
- }
+
+#if defined(TCP_FASTOPEN) && defined(__APPLE__)
+ if ( tfo
+ && setsockopt(listen_socket[v4n], IPPROTO_TCP, TCP_FASTOPEN, &on, sizeof(on))
+ && debug)
+ printf("setsockopt TCP_FASTOPEN: %s\n", strerror(errno));
+#endif
}
git://git.exim.org / exim.git / commitdiff