* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2014 */
+/* Copyright (c) University of Cambridge 1995 - 2016 */
/* See the file NOTICE for conditions of use and distribution. */
/* Functions for doing things with sockets. With the advent of IPv6 this has
ip_addr(void * sin_, int af, const uschar * address, int port)
{
union sockaddr_46 * sin = sin_;
-memset(sin, 0, sizeof(sin));
+memset(sin, 0, sizeof(*sin));
/* Setup code when using an IPv6 socket. The wildcard address is ":", to
ensure an IPv6 socket is used. */
address the remote address, in text form
port the remote port
timeout a timeout (zero for indefinite timeout)
+ fastopen TRUE iff TCP_FASTOPEN can be used
Returns: 0 on success; -1 on failure, with errno set
*/
int
-ip_connect(int sock, int af, const uschar *address, int port, int timeout)
+ip_connect(int sock, int af, const uschar *address, int port, int timeout,
+ BOOL fastopen)
{
struct sockaddr_in s_in4;
struct sockaddr *s_ptr;
/* If no connection timeout is set, just call connect() without setting a
timer, thereby allowing the inbuilt OS timeout to operate. */
+callout_address = string_sprintf("[%s]:%d", address, port);
sigalrm_seen = FALSE;
if (timeout > 0) alarm(timeout);
-rc = connect(sock, s_ptr, s_len);
+
+#if defined(TCP_FASTOPEN) && defined(MSG_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. Is there any usage where the former might be?
+We might extend the ip_connect() args for data if so. For now,
+connect in FASTOPEN mode but with zero data.
+*/
+
+if (fastopen)
+ {
+ if ( (rc = sendto(sock, NULL, 0, MSG_FASTOPEN, s_ptr, s_len)) < 0
+ && errno == EOPNOTSUPP
+ )
+ {
+ DEBUG(D_transport)
+ debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl");
+ rc = connect(sock, s_ptr, s_len);
+ }
+ }
+else
+#endif
+ rc = connect(sock, s_ptr, s_len);
+
save_errno = errno;
alarm(0);
/* Success */
-if (rc >= 0) return 0;
+if (rc >= 0)
+ return 0;
/* A failure whose error code is "Interrupted system call" is in fact
an externally applied timeout if the signal handler has been run. */
if (hostname[0] == '[' &&
hostname[namelen - 1] == ']')
{
- uschar * host = string_copy(hostname);
- host[namelen - 1] = 0;
- host++;
+ uschar * host = string_copyn(hostname+1, namelen-2);
if (string_is_ip_address(host, NULL) == 0)
{
*errstr = string_sprintf("malformed IP address \"%s\"", hostname);
/* Otherwise check for an unadorned IP address */
else if (string_is_ip_address(hostname, NULL) != 0)
- shost.name = shost.address = string_copy(hostname);
+ shost.name = shost.address = string_copyn(hostname, namelen);
/* Otherwise lookup IP address(es) from the name */
else
{
- shost.name = string_copy(hostname);
- if (host_find_byname(&shost, NULL, HOST_FIND_QUALIFY_SINGLE, NULL,
- FALSE) != HOST_FOUND)
+ shost.name = string_copyn(hostname, namelen);
+ if (host_find_byname(&shost, NULL, HOST_FIND_QUALIFY_SINGLE,
+ NULL, FALSE) != HOST_FOUND)
{
*errstr = string_sprintf("no IP address found for host %s", shost.name);
return -1;
/* Try to connect to the server - test each IP till one works */
-for (h = &shost; h != NULL; h = h->next)
+for (h = &shost; h; h = h->next)
{
- fd = (Ustrchr(h->address, ':') != 0)
- ? (fd6 < 0) ? (fd6 = ip_socket(type, af = AF_INET6)) : fd6
- : (fd4 < 0) ? (fd4 = ip_socket(type, af = AF_INET )) : fd4;
+ fd = Ustrchr(h->address, ':') != 0
+ ? fd6 < 0 ? (fd6 = ip_socket(type, af = AF_INET6)) : fd6
+ : fd4 < 0 ? (fd4 = ip_socket(type, af = AF_INET )) : fd4;
if (fd < 0)
{
}
for(port = portlo; port <= porthi; port++)
- if (ip_connect(fd, af, h->address, port, timeout) == 0)
+ if (ip_connect(fd, af, h->address, port, timeout, type == SOCK_STREAM) == 0)
{
if (fd != fd6) close(fd6);
if (fd != fd4) close(fd4);
return -1;
}
+callout_address = string_copy(path);
server.sun_family = AF_UNIX;
Ustrncpy(server.sun_path, path, sizeof(server.sun_path)-1);
server.sun_path[sizeof(server.sun_path)-1] = '\0';
fd_ready(int fd, int timeout)
{
fd_set select_inset;
-struct timeval tv;
time_t start_recv = time(NULL);
+int time_left = timeout;
int rc;
-if (timeout <= 0)
+if (time_left <= 0)
{
errno = ETIMEDOUT;
return FALSE;
do
{
+ struct timeval tv = { time_left, 0 };
FD_ZERO (&select_inset);
FD_SET (fd, &select_inset);
- tv.tv_sec = timeout;
- tv.tv_usec = 0;
/*DEBUG(D_transport) debug_printf("waiting for data on fd\n");*/
rc = select(fd + 1, (SELECT_ARG2_TYPE *)&select_inset, NULL, NULL, &tv);
Aug 2004: Somebody set up a cron job that ran exiwhat every 2 minutes, making
the interrupt not at all rare. Since the timeout is typically more than 2
minutes, the effect was to block the timeout completely. To prevent this
- happening again, we do an explicit time test. */
+ happening again, we do an explicit time test and adjust the timeout
+ accordingly */
if (rc < 0 && errno == EINTR)
{
DEBUG(D_transport) debug_printf("EINTR while waiting for socket data\n");
- if (time(NULL) - start_recv < timeout) continue;
- DEBUG(D_transport) debug_printf("total wait time exceeds timeout\n");
- }
- /* Handle a timeout, and treat any other select error as a timeout, including
- an EINTR when we have been in this loop for longer than timeout. */
+ /* Watch out, 'continue' jumps to the condition, not to the loops top */
+ time_left = timeout - (time(NULL) - start_recv);
+ if (time_left > 0) continue;
+ }
if (rc <= 0)
{
return FALSE;
}
- /* If the socket is ready, break out of the loop. */
+ /* Checking the FD_ISSET is not enough, if we're interrupted, the
+ select_inset may still contain the 'input'. */
}
-while (!FD_ISSET(fd, &select_inset));
+while (rc < 0 || !FD_ISSET(fd, &select_inset));
return TRUE;
}
projects / exim.git / blobdiff