* Proxy TLS connection for another transport process *
******************************************************/
/*
-Use the given buffer as a staging area, and select on both the given fd
-and the TLS'd client-fd for data to read (per the coding in ip_recv() and
-fd_ready() this is legitimate). Do blocking full-size writes, and reads
-under a timeout.
+Close the unused end of the pipe, fork once more, then use the given buffer
+as a staging area, and select on both the given fd and the TLS'd client-fd for
+data to read (per the coding in ip_recv() and fd_ready() this is legitimate).
+Do blocking full-size writes, and reads under a timeout. Once both input
+channels are closed, exit the process.
Arguments:
buf space to use for buffering
bufsiz size of buffer
- proxy_fd comms to proxied process
+ pfd pipe filedescriptor array; [0] is comms to proxied process
timeout per-read timeout, seconds
*/
void
-smtp_proxy_tls(uschar * buf, size_t bsize, int proxy_fd, int timeout)
+smtp_proxy_tls(uschar * buf, size_t bsize, int * pfd, int timeout)
{
fd_set rfds, efds;
-int max_fd = MAX(proxy_fd, tls_out.active) + 1;
+int max_fd = MAX(pfd[0], tls_out.active) + 1;
int rc, i, fd_bits, nbytes;
+close(pfd[1]);
+if ((rc = fork()))
+ {
+ DEBUG(D_transport) debug_printf("proxy-proc final-pid %d\n", rc);
+ _exit(rc < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+ }
+
set_process_info("proxying TLS connection for continued transport");
FD_ZERO(&rfds);
FD_SET(tls_out.active, &rfds);
-FD_SET(proxy_fd, &rfds);
+FD_SET(pfd[0], &rfds);
for (fd_bits = 3; fd_bits; )
{
if (rc <= 0)
{
DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
- return;
+ goto done;
}
- if (FD_ISSET(tls_out.active, &efds) || FD_ISSET(proxy_fd, &efds))
+ if (FD_ISSET(tls_out.active, &efds) || FD_ISSET(pfd[0], &efds))
{
DEBUG(D_transport) debug_printf("select: exceptional cond on %s fd\n",
- FD_ISSET(proxy_fd, &efds) ? "proxy" : "tls");
- return;
+ FD_ISSET(pfd[0], &efds) ? "proxy" : "tls");
+ goto done;
}
}
- while (rc < 0 || !(FD_ISSET(tls_out.active, &rfds) || FD_ISSET(proxy_fd, &rfds)));
+ while (rc < 0 || !(FD_ISSET(tls_out.active, &rfds) || FD_ISSET(pfd[0], &rfds)));
/* handle inbound data */
if (FD_ISSET(tls_out.active, &rfds))
{
fd_bits &= ~1;
FD_CLR(tls_out.active, &rfds);
- shutdown(proxy_fd, SHUT_WR);
+ shutdown(pfd[0], SHUT_WR);
timeout = 5;
}
else
{
for (nbytes = 0; rc - nbytes > 0; nbytes += i)
- if ((i = write(proxy_fd, buf + nbytes, rc - nbytes)) < 0) return;
+ if ((i = write(pfd[0], buf + nbytes, rc - nbytes)) < 0) goto done;
}
else if (fd_bits & 1)
FD_SET(tls_out.active, &rfds);
/* handle outbound data */
- if (FD_ISSET(proxy_fd, &rfds))
- if ((rc = read(proxy_fd, buf, bsize)) <= 0)
+ if (FD_ISSET(pfd[0], &rfds))
+ if ((rc = read(pfd[0], buf, bsize)) <= 0)
{
fd_bits = 0;
tls_close(FALSE, TRUE);
{
for (nbytes = 0; rc - nbytes > 0; nbytes += i)
if ((i = tls_write(FALSE, buf + nbytes, rc - nbytes, FALSE)) < 0)
- return;
+ goto done;
}
else if (fd_bits & 2)
- FD_SET(proxy_fd, &rfds);
+ FD_SET(pfd[0], &rfds);
}
+
+done:
+ if (running_in_test_harness) millisleep(100); /* let logging complete */
+ exim_exit(0, US"TLS proxy");
}
#endif
{
sx.send_quit = FALSE;
- /* If TLS is still active, we need to proxy it for the transport we
+ /* We have passed the client socket to a fresh transport process.
+ If TLS is still active, we need to proxy it for the transport we
just passed the baton to. Fork a child to to do it, and return to
get logging done asap. Which way to place the work makes assumptions
about post-fork prioritisation which may not hold on all platforms. */
if (tls_out.active >= 0)
{
int pid = fork();
+ if (pid == 0) /* child; fork again to disconnect totally */
+ /* does not return */
+ smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd,
+ sx.ob->command_timeout);
+
if (pid > 0) /* parent */
{
DEBUG(D_transport) debug_printf("proxy-proc inter-pid %d\n", pid);
close(pfd[0]);
+ /* tidy the inter-proc to disconn the proxy proc */
waitpid(pid, NULL, 0);
tls_close(FALSE, FALSE);
(void)close(sx.inblock.sock);
continue_hostname = NULL;
return yield;
}
- else if (pid == 0) /* child; fork again to disconnect totally */
- {
- close(pfd[1]);
- if ((pid = fork()))
- {
- DEBUG(D_transport) debug_printf("proxy-prox final-pid %d\n", pid);
- _exit(pid < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
- }
- smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd[0], sx.ob->command_timeout);
- if (running_in_test_harness) millisleep(100); /* let logging complete */
- exim_exit(0, US"TLS proxy");
- }
+ log_write(0, LOG_PANIC_DIE, "fork failed");
}
#endif
}
git://git.exim.org / exim.git / commitdiff