Gitweb:
https://git.exim.org/exim.git/commitdiff/73a10da9bbc6aadd03c3aff7a12307252e617a71
Commit: 73a10da9bbc6aadd03c3aff7a12307252e617a71
Parent: ab6b4fdbded98ca6d185409e3c419ab1bfb26422
Author: Jeremy Harris <jgh146exb@???>
AuthorDate: Tue Dec 3 22:12:09 2019 +0000
Committer: Jeremy Harris <jgh146exb@???>
CommitDate: Sun Dec 8 11:36:23 2019 +0000
FreeBSD: better support for TFO
---
src/OS/os.c-FreeBSD | 23 +++++++++-
src/OS/os.h-FreeBSD | 8 +---
src/src/ip.c | 57 ++++++++++++------------
src/src/smtp_in.c | 25 ++++++++---
src/src/smtp_out.c | 26 +++++++++--
src/src/transport.c | 85 ++++++++++++++++++++----------------
test/scripts/1990-TCP-Fast-Open/1990 | 10 ++---
7 files changed, 148 insertions(+), 86 deletions(-)
diff --git a/src/OS/os.c-FreeBSD b/src/OS/os.c-FreeBSD
index 4cc46c7..c0fd48d 100644
--- a/src/OS/os.c-FreeBSD
+++ b/src/OS/os.c-FreeBSD
@@ -10,7 +10,7 @@ src/os.c file. */
/*************
-* Sendfile *
+Sendfile shim
*************/
ssize_t
@@ -23,4 +23,25 @@ if (sendfile(in, out, loff, cnt, NULL, &written, 0) < 0) return (ssize_t)-1;
return (ssize_t)written;
}
+/*************************************************
+TCP Fast Open: check that the ioctl is accepted
+*************************************************/
+
+#ifndef COMPILE_UTILITY
+void
+tfo_probe(void)
+{
+# ifdef TCP_FASTOPEN
+int sock;
+
+if ( (sock = socket(AF_INET, SOCK_STREAM, 0)) >= 0
+ && setsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &on, sizeof(on) >= 0)
+ )
+ f.tcp_fastopen_ok = TRUE;
+close(sock);
+# endif
+}
+#endif
+
+
/* End of os.c-Linux */
diff --git a/src/OS/os.h-FreeBSD b/src/OS/os.h-FreeBSD
index 4f1c616..a15d475 100644
--- a/src/OS/os.h-FreeBSD
+++ b/src/OS/os.h-FreeBSD
@@ -57,15 +57,9 @@ extern ssize_t os_sendfile(int, int, off_t *, size_t);
/*******************/
-/* TCP_FASTOPEN support. There does not seems to be a
-MSG_FASTOPEN defined yet... */
#define EXIM_TFO_PROBE
+#define EXIM_TFO_FREEBSD
-#include <netinet/tcp.h> /* for TCP_FASTOPEN */
-#include <sys/socket.h> /* for MSG_FASTOPEN */
-#if defined(TCP_FASTOPEN) && !defined(MSG_FASTOPEN)
-# define MSG_FASTOPEN 0x20000000
-#endif
/* for TCP state-variable values, for TFO logging */
#include <netinet/tcp_fsm.h>
diff --git a/src/src/ip.c b/src/src/ip.c
index 70e3e20..108c21d 100644
--- a/src/src/ip.c
+++ b/src/src/ip.c
@@ -14,6 +14,12 @@ different places in the code where sockets are used. */
#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 *
*************************************************/
@@ -161,26 +167,6 @@ return bind(sock, (struct sockaddr *)&sin, s_len);
/*************************************************
-*************************************************/
-
-#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 *
*************************************************/
@@ -245,7 +231,7 @@ callout_address = string_sprintf("[%s]:%d", address, port);
sigalrm_seen = FALSE;
if (timeout > 0) ALARM(timeout);
-#if defined(TCP_FASTOPEN) && (defined(MSG_FASTOPEN) || defined(EXIM_TFO_CONNECTX))
+#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
@@ -255,8 +241,7 @@ 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. FreeBSD does not seem to have MSG_FASTOPEN so
- how to get TFO is unknown. */
+ /* This is a Linux implementation. */
if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len,
MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0)
@@ -292,8 +277,26 @@ if (fastopen_blob && f.tcp_fastopen_ok)
debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n");
goto legacy_connect;
}
-# endif
-# ifdef EXIM_TFO_CONNECTX
+
+# 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;
+ }
+ 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,
@@ -329,9 +332,9 @@ if (fastopen_blob && f.tcp_fastopen_ok)
# 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
diff --git a/src/src/smtp_in.c b/src/src/smtp_in.c
index b88fde1..c2e234a 100644
--- a/src/src/smtp_in.c
+++ b/src/src/smtp_in.c
@@ -2405,20 +2405,35 @@ struct tcp_info tinfo;
socklen_t len = sizeof(tinfo);
if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0)
-#ifdef TCPI_OPT_SYN_DATA /* FreeBSD 11 does not seem to have this yet */
+# ifdef TCPI_OPT_SYN_DATA /* FreeBSD 11,12 do not seem to have this yet */
if (tinfo.tcpi_options & TCPI_OPT_SYN_DATA)
{
- DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (ACKd data-on-SYN)\n");
+ DEBUG(D_receive)
+ debug_printf("TCP_FASTOPEN mode connection (ACKd data-on-SYN)\n");
f.tcp_in_fastopen_data = f.tcp_in_fastopen = TRUE;
}
else
-#endif
- if (tinfo.tcpi_state == TCP_SYN_RECV)
+# endif
+ if (tinfo.tcpi_state == TCP_SYN_RECV) /* Not seen on FreeBSD 12.1 */
+ {
+ DEBUG(D_receive)
+ debug_printf("TCP_FASTOPEN mode connection (state TCP_SYN_RECV)\n");
+ f.tcp_in_fastopen = TRUE;
+ }
+# ifdef __FreeBSD__
+ else if (tinfo.tcpi_options & TCPOPT_FAST_OPEN)
{
- DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (state TCP_SYN_RECV)\n");
+ /* This only tells us that some combination of the TCP options was used. It
+ can be a TFO-R received (as of 12.1). However, pretend it shows real usage
+ (that an acceptable TFO-C was received and acted on). Ignore the possibility
+ of data-on-SYN for now. */
+ DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (TFO option used)\n");
f.tcp_in_fastopen = TRUE;
}
+# endif
# endif
+else DEBUG(D_receive)
+ debug_printf("TCP_INFO getsockopt: %s\n", strerror(errno));
}
#endif
diff --git a/src/src/smtp_out.c b/src/src/smtp_out.c
index 07cc9b7..3dc3a13 100644
--- a/src/src/smtp_out.c
+++ b/src/src/smtp_out.c
@@ -155,9 +155,28 @@ return TRUE;
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);
+int val;
+socklen_t len = sizeof(val);
+
+# ifdef __FreeBSD__
+/* The observability as of 12.1 is not useful as a client, only telling us that
+a TFO option was used on SYN. It could have been a TFO-R, or ignored by the
+server. */
+
+/*
+if (tcp_out_fastopen == TFO_ATTEMPTED_NODATA || tcp_out_fastopen == TFO_ATTEMPTED_DATA)
+ if (getsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &val, &len) == 0 && val != 0) {}
+*/
+switch (tcp_out_fastopen)
+ {
+ case TFO_ATTEMPTED_NODATA: tcp_out_fastopen = TFO_USED_NODATA; break;
+ case TFO_ATTEMPTED_DATA: tcp_out_fastopen = TFO_USED_DATA; break;
+ default: break; /* compiler quietening */
+ }
+
+# else /* Linux & Apple */
+# if defined(TCP_INFO) && defined(EXIM_HAVE_TCPI_UNACKED)
switch (tcp_out_fastopen)
{
@@ -205,7 +224,8 @@ switch (tcp_out_fastopen)
default: break; /* compiler quietening */
}
-# endif
+# endif
+# endif /* Linux & Apple */
}
#endif
diff --git a/src/src/transport.c b/src/src/transport.c
index df7fd16..14bd91c 100644
--- a/src/src/transport.c
+++ b/src/src/transport.c
@@ -172,6 +172,20 @@ for (transport_instance * t = transports; t; t = t->next)
* Write block of data *
*************************************************/
+static int
+tpt_write(int fd, uschar * block, int len, BOOL more, int options)
+{
+return
+#ifndef DISABLE_TLS
+ tls_out.active.sock == fd
+ ? tls_write(tls_out.active.tls_ctx, block, len, more) :
+#endif
+#ifdef MSG_MORE
+ more && !(options & topt_not_socket) ? send(fd, block, len, MSG_MORE) :
+#endif
+ write(fd, block, len);
+}
+
/* Subroutine called by write_chunk() and at the end of the message actually
to write a data block. Also called directly by some transports to write
additional data to the file descriptor (e.g. prefix, suffix).
@@ -215,10 +229,11 @@ Returns: TRUE on success, FALSE on failure (with errno preserved);
*/
static BOOL
-transport_write_block_fd(transport_ctx * tctx, uschar *block, int len, BOOL more)
+transport_write_block_fd(transport_ctx * tctx, uschar * block, int len, BOOL more)
{
int rc, save_errno;
int local_timeout = transport_write_timeout;
+int connretry = 1;
int fd = tctx->u.fd;
/* This loop is for handling incomplete writes and other retries. In most
@@ -230,48 +245,42 @@ for (int i = 0; i < 100; i++)
debug_printf("writing data block fd=%d size=%d timeout=%d%s\n",
fd, len, local_timeout, more ? " (more expected)" : "");
- /* This code makes use of alarm() in order to implement the timeout. This
- isn't a very tidy way of doing things. Using non-blocking I/O with select()
- provides a neater approach. However, I don't know how to do this when TLS is
- in use. */
-
- if (transport_write_timeout <= 0) /* No timeout wanted */
- {
- rc =
-#ifndef DISABLE_TLS
- tls_out.active.sock == fd ? tls_write(tls_out.active.tls_ctx, block, len, more) :
-#endif
-#ifdef MSG_MORE
- more && !(tctx->options & topt_not_socket)
- ? send(fd, block, len, MSG_MORE) :
-#endif
- write(fd, block, len);
- save_errno = errno;
- }
+ /* When doing TCP Fast Open we may get this far before the 3-way handshake
+ is complete, and write returns ENOTCONN. Detect that, wait for the socket
+ to become writable, and retry once only. */
- /* Timeout wanted. */
-
- else
+ for(;;)
{
- ALARM(local_timeout);
+ fd_set fds;
+ /* This code makes use of alarm() in order to implement the timeout. This
+ isn't a very tidy way of doing things. Using non-blocking I/O with select()
+ provides a neater approach. However, I don't know how to do this when TLS is
+ in use. */
- rc =
-#ifndef DISABLE_TLS
- tls_out.active.sock == fd ? tls_write(tls_out.active.tls_ctx, block, len, more) :
-#endif
-#ifdef MSG_MORE
- more && !(tctx->options & topt_not_socket)
- ? send(fd, block, len, MSG_MORE) :
-#endif
- write(fd, block, len);
-
- save_errno = errno;
- local_timeout = ALARM_CLR(0);
- if (sigalrm_seen)
+ if (transport_write_timeout <= 0) /* No timeout wanted */
{
- errno = ETIMEDOUT;
- return FALSE;
+ rc = tpt_write(fd, block, len, more, tctx->options);
+ save_errno = errno;
}
+ else /* Timeout wanted. */
+ {
+ ALARM(local_timeout);
+ rc = tpt_write(fd, block, len, more, tctx->options);
+ save_errno = errno;
+ local_timeout = ALARM_CLR(0);
+ if (sigalrm_seen)
+ {
+ errno = ETIMEDOUT;
+ return FALSE;
+ }
+ }
+
+ if (rc >= 0 || errno != ENOTCONN || connretry <= 0)
+ break;
+
+ FD_ZERO(&fds); FD_SET(fd, &fds);
+ select(fd+1, NULL, &fds, NULL, NULL); /* could set timout? */
+ connretry--;
}
/* Hopefully, the most common case is success, so test that first. */
diff --git a/test/scripts/1990-TCP-Fast-Open/1990 b/test/scripts/1990-TCP-Fast-Open/1990
index 1fc4682..80059e6 100644
--- a/test/scripts/1990-TCP-Fast-Open/1990
+++ b/test/scripts/1990-TCP-Fast-Open/1990
@@ -22,6 +22,11 @@
# which might do the job. But how to manipulate it?
#
#
+# FreeBSD: it looks like you have to compile a custom kernel, with
+# 'options TCP_RFC7413' in the config. Also set
+# 'net.inet.tcp.fastopen.server_enable=1' in /etc/sysctl.conf
+# Seems to always claim TFO used by transport, if tried.
+#
sudo perl
system ("tc qdisc add dev lo root netem delay 50ms");
****
@@ -50,11 +55,6 @@ system ("ip tcp_metrics delete 127.0.0.1");
#
#
#
-# FreeBSD: it looks like you have to compile a custom kernel, with
-# 'options TCP_RFC7413' in the config. Also set
-# 'net.inet.tcp.fastopen.enabled=1' in /etc/sysctl.conf
-# Untested.
-#
exim -DSERVER=server -bd -oX PORT_D
****
#
