* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2016 */
+/* Copyright (c) University of Cambridge 1995 - 2017 */
/* See the file NOTICE for conditions of use and distribution. */
#include "../exim.h"
#ifdef SUPPORT_TLS
{ "hosts_nopass_tls", opt_stringptr,
(void *)offsetof(smtp_transport_options_block, hosts_nopass_tls) },
+ { "hosts_noproxy_tls", opt_stringptr,
+ (void *)offsetof(smtp_transport_options_block, hosts_noproxy_tls) },
#endif
{ "hosts_override", opt_bool,
(void *)offsetof(smtp_transport_options_block, hosts_override) },
NULL, /* hosts_verify_avoid_tls */
NULL, /* hosts_avoid_pipelining */
NULL, /* hosts_avoid_esmtp */
+#ifdef SUPPORT_TLS
NULL, /* hosts_nopass_tls */
+ US"*", /* hosts_noproxy_tls */
+#endif
5*60, /* command_timeout */
5*60, /* connect_timeout; shorter system default overrides */
5*60, /* data timeout */
static uschar *mail_command; /* Points to MAIL cmd for error messages */
static uschar *data_command = US""; /* Points to DATA cmd for error messages */
static BOOL update_waiting; /* TRUE to update the "wait" database */
+
+/*XXX move to smtp_context */
static BOOL pipelining_active; /* current transaction is in pipe mode */
*message = US string_sprintf("Remote host closed connection "
"in response to %s%s", pl, smtp_command);
}
-else *message = US string_sprintf("%s [%s]", host->name, host->address);
+else
+ *message = US string_sprintf("%s [%s]", host->name, host->address);
return FALSE;
}
If given a nonzero size, first flush any buffered SMTP commands
then emit the command.
-Reap previous SMTP command responses if requested.
-Reap one SMTP command response if requested.
+Reap previous SMTP command responses if requested, and always reap
+the response from a previous BDAT command.
+
+Args:
+ tctx transport context
+ chunk_size value for SMTP BDAT command
+ flags
+ tc_chunk_last add LAST option to SMTP BDAT command
+ tc_reap_prev reap response to previous SMTP commands
Returns: OK or ERROR
*/
static int
-smtp_chunk_cmd_callback(int fd, transport_ctx * tctx,
- unsigned chunk_size, unsigned flags)
+smtp_chunk_cmd_callback(transport_ctx * tctx, unsigned chunk_size,
+ unsigned flags)
{
smtp_transport_options_block * ob =
(smtp_transport_options_block *)(tctx->tblock->options_block);
if (errno == 0 && sx->buffer[0] == '4')
{
errno = ERRNO_DATA4XX; /*XXX does this actually get used? */
- sx->first_addr->more_errno |=
+ sx->addrlist->more_errno |=
((sx->buffer[1] - '0')*10 + sx->buffer[2] - '0') << 8;
}
return ERROR;
dns_answer tlsa_dnsa;
#endif
BOOL pass_message = FALSE;
-
uschar * message = NULL;
-int save_errno;
int yield = OK;
int rc;
if (sx->inblock.sock < 0)
{
uschar * msg = NULL;
- int save_errno = errno;
if (sx->verify)
{
- msg = strerror(errno);
+ msg = US strerror(errno);
HDEBUG(D_verify) debug_printf("connect: %s\n", msg);
}
set_errno_nohost(sx->addrlist,
- save_errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : save_errno,
+ errno == ETIMEDOUT ? ERRNO_CONNECTTIMEOUT : errno,
sx->verify ? string_sprintf("could not connect: %s", msg)
: NULL,
DEFER, FALSE);
if (rsp != sx->buffer && rsp[0] == 0 && (errno == 0 || errno == ECONNRESET))
{
- sx->send_quit = FALSE;
- save_errno = ERRNO_SMTPCLOSED;
- message = string_sprintf("Remote host closed connection "
- "in response to %s (EHLO response was: %s)",
- smtp_command, sx->buffer);
- goto FAILED;
+ errno = ERRNO_SMTPCLOSED;
+ goto EHLOHELO_FAILED;
}
Ustrncpy(sx->buffer, rsp, sizeof(sx->buffer)/2);
goto RESPONSE_FAILED;
}
}
-/* For continuing deliveries down the same channel, the socket is the standard
-input, and we don't need to redo EHLO here (but may need to do so for TLS - see
-below). Set up the pointer to where subsequent commands will be left, for
+/* For continuing deliveries down the same channel, having re-exec'd the socket
+is the standard input; for a socket held open from verify it is recorded
+in the cutthrough context block. Either way we don't need to redo EHLO here
+(but may need to do so for TLS - see below).
+Set up the pointer to where subsequent commands will be left, for
error messages. Note that smtp_peer_options will have been
set from the command line if they were set in the process that passed the
connection on. */
else
{
- sx->inblock.sock = sx->outblock.sock = fileno(stdin);
+ if (cutthrough.fd >= 0 && cutthrough.callout_hold_only)
+ {
+ sx->inblock.sock = sx->outblock.sock = cutthrough.fd;
+ sx->host->port = sx->port = cutthrough.host.port;
+ }
+ else
+ {
+ sx->inblock.sock = sx->outblock.sock = 0; /* stdin */
+ sx->host->port = sx->port; /* Record the port that was used */
+ }
smtp_command = big_buffer;
- sx->host->port = sx->port; /* Record the port that was used */
sx->helo_data = NULL; /* ensure we re-expand ob->helo_data */
+
+ /* For a continued connection with TLS being proxied for us, or a
+ held-open verify connection with TLS, nothing more to do. */
+
+ if ( continue_proxy_cipher
+ || (cutthrough.fd >= 0 && cutthrough.callout_hold_only && cutthrough.is_tls)
+ )
+ {
+ sx->peer_offered = smtp_peer_options;
+ pipelining_active = !!(smtp_peer_options & PEER_OFFERED_PIPE);
+ HDEBUG(D_transport) debug_printf("continued connection, %s TLS\n",
+ continue_proxy_cipher ? "proxied" : "verify conn with");
+ return OK;
+ }
+ HDEBUG(D_transport) debug_printf("continued connection, no TLS\n");
}
/* If TLS is available on this connection, whether continued or not, attempt to
TLS_NEGOTIATE:
{
address_item * addr;
- int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock
+ uschar * errstr;
+ int rc = tls_client_start(sx->inblock.sock, sx->host, sx->addrlist, sx->tblock,
# ifdef EXPERIMENTAL_DANE
- , sx->dane ? &tlsa_dnsa : NULL
+ sx->dane ? &tlsa_dnsa : NULL,
# endif
- );
+ &errstr);
/* TLS negotiation failed; give an error. From outside, this function may
be called again to try in clear on a new connection, if the options permit
{
# ifdef EXPERIMENTAL_DANE
if (sx->dane) log_write(0, LOG_MAIN,
- "DANE attempt failed; no TLS connection to %s [%s]",
- sx->host->name, sx->host->address);
+ "DANE attempt failed; TLS connection to %s [%s]: %s",
+ sx->host->name, sx->host->address, errstr);
# endif
- save_errno = ERRNO_TLSFAILURE;
- message = US"failure while setting up TLS session";
+ errno = ERRNO_TLSFAILURE;
+ message = string_sprintf("TLS session: %s", errstr);
sx->send_quit = FALSE;
goto TLS_FAILED;
}
|| verify_check_given_host(&sx->ob->hosts_require_tls, sx->host) == OK
)
{
- save_errno = ERRNO_TLSREQUIRED;
+ errno = ERRNO_TLSREQUIRED;
message = string_sprintf("a TLS session is required, but %s",
smtp_peer_options & PEER_OFFERED_TLS
? "an attempt to start TLS failed" : "the server did not offer TLS support");
{
int code;
- uschar * set_message;
RESPONSE_FAILED:
- {
- save_errno = errno;
message = NULL;
- sx->send_quit = check_response(sx->host, &save_errno, sx->addrlist->more_errno,
+ sx->send_quit = check_response(sx->host, &errno, sx->addrlist->more_errno,
sx->buffer, &code, &message, &pass_message);
goto FAILED;
- }
SEND_FAILED:
- {
- save_errno = errno;
code = '4';
message = US string_sprintf("send() to %s [%s] failed: %s",
- sx->host->name, sx->host->address, strerror(save_errno));
+ sx->host->name, sx->host->address, strerror(errno));
sx->send_quit = FALSE;
goto FAILED;
- }
/* This label is jumped to directly when a TLS negotiation has failed,
or was not done for a host for which it is required. Values will be set
- in message and save_errno, and setting_up will always be true. Treat as
+ in message and errno, and setting_up will always be true. Treat as
a temporary error. */
+ EHLOHELO_FAILED:
+ code = '4';
+ message = string_sprintf("Remote host closed connection in response to %s"
+ " (EHLO response was: %s)", smtp_command, sx->buffer);
+ sx->send_quit = FALSE;
+ goto FAILED;
+
#ifdef SUPPORT_TLS
TLS_FAILED:
- code = '4';
+ code = '4';
+ goto FAILED;
#endif
/* The failure happened while setting up the call; see if the failure was
whatever), defer all addresses, and yield DEFER, so that the host is not
tried again for a while. */
- FAILED:
+FAILED:
sx->ok = FALSE; /* For when reached by GOTO */
- set_message = message;
yield = code == '5'
#ifdef SUPPORT_I18N
#endif
? FAIL : DEFER;
- set_errno(sx->addrlist, save_errno, set_message, yield, pass_message, sx->host
+ set_errno(sx->addrlist, errno, message, yield, pass_message, sx->host
#ifdef EXPERIMENTAL_DSN_INFO
, sx->smtp_greeting, sx->helo_response
#endif
specified in the transports, and therefore not visible at top level, in which
case continue_more won't get set. */
-HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
+HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
if (sx->send_quit)
{
shutdown(sx->outblock.sock, SHUT_WR);
}
+#ifdef SUPPORT_TLS
+/*****************************************************
+* 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.
+
+Arguments:
+ buf space to use for buffering
+ bufsiz size of buffer
+ proxy_fd comms to proxied process
+ timeout per-read timeout, seconds
+*/
+
+void
+smtp_proxy_tls(uschar * buf, size_t bsize, int proxy_fd, int timeout)
+{
+fd_set fds;
+int max_fd = MAX(proxy_fd, tls_out.active) + 1;
+int rc, i, fd_bits, nbytes;
+
+set_process_info("proxying TLS connection for continued transport");
+FD_ZERO(&fds);
+FD_SET(tls_out.active, &fds);
+FD_SET(proxy_fd, &fds);
+
+for (fd_bits = 3; fd_bits; )
+ {
+ time_t time_left = timeout;
+ time_t time_start = time(NULL);
+
+ /* wait for data */
+ do
+ {
+ struct timeval tv = { time_left, 0 };
+
+ rc = select(max_fd, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tv);
+
+ if (rc < 0 && errno == EINTR)
+ if ((time_left -= time(NULL) - time_start) > 0) continue;
+
+ if (rc <= 0)
+ {
+ DEBUG(D_transport) if (rc == 0) debug_printf("%s: timed out\n", __FUNCTION__);
+ return;
+ }
+ }
+ while (rc < 0 || !(FD_ISSET(tls_out.active, &fds) || FD_ISSET(proxy_fd, &fds)));
+
+ /* handle inbound data */
+ if (FD_ISSET(tls_out.active, &fds))
+ if ((rc = tls_read(FALSE, buf, bsize)) <= 0)
+ {
+ fd_bits &= ~1;
+ FD_CLR(tls_out.active, &fds);
+ shutdown(proxy_fd, SHUT_WR);
+ }
+ else
+ {
+ for (nbytes = 0; rc - nbytes > 0; nbytes += i)
+ if ((i = write(proxy_fd, buf + nbytes, rc - nbytes)) < 0) return;
+ }
+ else if (fd_bits & 1)
+ FD_SET(tls_out.active, &fds);
+
+ /* handle outbound data */
+ if (FD_ISSET(proxy_fd, &fds))
+ if ((rc = read(proxy_fd, buf, bsize)) <= 0)
+ {
+ fd_bits &= ~2;
+ FD_CLR(proxy_fd, &fds);
+ shutdown(tls_out.active, SHUT_WR);
+ }
+ else
+ {
+ for (nbytes = 0; rc - nbytes > 0; nbytes += i)
+ if ((i = tls_write(FALSE, buf + nbytes, rc - nbytes)) < 0) return;
+ }
+ else if (fd_bits & 2)
+ FD_SET(proxy_fd, &fds);
+ }
+}
+#endif
+
+
/*************************************************
* Deliver address list to given host *
*************************************************/
sx.completed_addr = FALSE;
-/* Initiate a message transfer. */
+/* If we are a continued-connection-after-verify the MAIL and RCPT
+commands were already sent; do not re-send but do mark the addrs as
+having been accepted up to RCPT stage. A traditional cont-conn
+always has a sequence number greater than one. */
-switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
+if (continue_hostname && continue_sequence == 1)
{
- case 0: break;
- case -1: case -2: goto RESPONSE_FAILED;
- case -3: goto END_OFF;
- case -4: goto SEND_QUIT;
- default: goto SEND_FAILED;
- }
+ address_item * addr;
-/* If we are an MUA wrapper, abort if any RCPTs were rejected, either
-permanently or temporarily. We should have flushed and synced after the last
-RCPT. */
+ sx.peer_offered = smtp_peer_options;
+ sx.ok = TRUE;
+ sx.next_addr = NULL;
-if (mua_wrapper)
+ for (addr = addrlist; addr; addr = addr->next)
+ addr->transport_return = PENDING_OK;
+ }
+else
{
- address_item *badaddr;
- for (badaddr = sx.first_addr; badaddr; badaddr = badaddr->next)
- if (badaddr->transport_return != PENDING_OK)
- {
- /*XXX could we find a better errno than 0 here? */
- set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
- testflag(badaddr, af_pass_message));
- sx.ok = FALSE;
- break;
- }
+ /* Initiate a message transfer. */
+
+ switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
+ {
+ case 0: break;
+ case -1: case -2: goto RESPONSE_FAILED;
+ case -3: goto END_OFF;
+ case -4: goto SEND_QUIT;
+ default: goto SEND_FAILED;
+ }
+
+ /* If we are an MUA wrapper, abort if any RCPTs were rejected, either
+ permanently or temporarily. We should have flushed and synced after the last
+ RCPT. */
+
+ if (mua_wrapper)
+ {
+ address_item *badaddr;
+ for (badaddr = sx.first_addr; badaddr; badaddr = badaddr->next)
+ if (badaddr->transport_return != PENDING_OK)
+ {
+ /*XXX could we find a better errno than 0 here? */
+ set_errno_nohost(addrlist, 0, badaddr->message, FAIL,
+ testflag(badaddr, af_pass_message));
+ sx.ok = FALSE;
+ break;
+ }
+ }
}
/* If ok is TRUE, we know we have got at least one good recipient, and must now
transport_count = 0;
#ifndef DISABLE_DKIM
- sx.ok = dkim_transport_write_message(sx.inblock.sock, &tctx, &sx.ob->dkim);
+ sx.ok = dkim_transport_write_message(sx.inblock.sock, &tctx, &sx.ob->dkim,
+ CUSS &message);
#else
sx.ok = transport_write_message(sx.inblock.sock, &tctx, 0);
#endif
Or, when CHUNKING, it can be a protocol-detected failure. */
if (!sx.ok)
- goto RESPONSE_FAILED;
+ if (message) goto SEND_FAILED;
+ else goto RESPONSE_FAILED;
/* We used to send the terminating "." explicitly here, but because of
buffering effects at both ends of TCP/IP connections, you don't gain
else
sprintf(CS sx.buffer, "%.500s\n", addr->unique);
- DEBUG(D_deliver) debug_printf("journalling %s\n", sx.buffer);
+ DEBUG(D_deliver) debug_printf("S:journalling %s\n", sx.buffer);
len = Ustrlen(CS sx.buffer);
if (write(journal_fd, sx.buffer, len) != len)
log_write(0, LOG_MAIN|LOG_PANIC, "failed to write journal for "
{
save_errno = errno;
code = '4';
- message = US string_sprintf("send() to %s [%s] failed: %s",
- host->name, host->address, strerror(save_errno));
+ message = string_sprintf("send() to %s [%s] failed: %s",
+ host->name, host->address, message ? message : US strerror(save_errno));
sx.send_quit = FALSE;
goto FAILED;
}
if ( sx.first_addr != NULL
|| continue_more
- || ( ( tls_out.active < 0
+ || (
+#ifdef SUPPORT_TLS
+ ( tls_out.active < 0 && !continue_proxy_cipher
|| verify_check_given_host(&sx.ob->hosts_nopass_tls, host) != OK
)
&&
+#endif
transport_check_waiting(tblock->name, host->name,
tblock->connection_max_messages, new_message_id, &more,
(oicf)smtp_are_same_identities, (void*)&t_compare)
if (sx.ok)
{
- if (sx.first_addr != NULL) /* More addresses still to be sent */
+ int pfd[2];
+ int socket_fd = sx.inblock.sock;
+
+
+ if (sx.first_addr != NULL) /* More addresses still to be sent */
{ /* in this run of the transport */
continue_sequence++; /* Causes * in logging */
goto SEND_MESSAGE;
}
if (continue_more) return yield; /* More addresses for another run */
- /* Pass the socket to a new Exim process. Before doing so, we must shut
- down TLS. Not all MTAs allow for the continuation of the SMTP session
- when TLS is shut down. We test for this by sending a new EHLO. If we
- don't get a good response, we don't attempt to pass the socket on. */
-
+ /* Pass the connection on to a new Exim process. */
#ifdef SUPPORT_TLS
if (tls_out.active >= 0)
- {
- tls_close(FALSE, TRUE);
- smtp_peer_options = smtp_peer_options_wrap;
- sx.ok = !sx.smtps
- && smtp_write_command(&sx.outblock, FALSE,
- "EHLO %s\r\n", sx.helo_data) >= 0
- && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
- '2', sx.ob->command_timeout);
- }
+ if (verify_check_given_host(&sx.ob->hosts_noproxy_tls, host) == OK)
+ {
+ /* Pass the socket, for direct use, to a new Exim process. Before
+ doing so, we must shut down TLS. Not all MTAs allow for the
+ continuation of the SMTP session when TLS is shut down. We test for
+ this by sending a new EHLO. If we don't get a good response, we don't
+ attempt to pass the socket on. */
+
+ tls_close(FALSE, TRUE);
+ smtp_peer_options = smtp_peer_options_wrap;
+ sx.ok = !sx.smtps
+ && smtp_write_command(&sx.outblock, FALSE,
+ "EHLO %s\r\n", sx.helo_data) >= 0
+ && smtp_read_response(&sx.inblock, sx.buffer, sizeof(sx.buffer),
+ '2', sx.ob->command_timeout);
+ }
+ else
+ {
+ /* Set up a pipe for proxying TLS for the new transport process */
+
+ smtp_peer_options |= PEER_OFFERED_TLS;
+ if (sx.ok = (socketpair(AF_UNIX, SOCK_STREAM, 0, pfd) == 0))
+ socket_fd = pfd[1];
+ else
+ set_errno(sx.first_addr, errno, US"internal allocation problem",
+ DEFER, FALSE, host
+# ifdef EXPERIMENTAL_DSN_INFO
+ , sx.smtp_greeting, sx.helo_response
+# endif
+ );
+ }
#endif
/* If the socket is successfully passed, we mustn't send QUIT (or
propagate it from the initial
*/
if (sx.ok && transport_pass_socket(tblock->name, host->name,
- host->address, new_message_id, sx.inblock.sock))
+ host->address, new_message_id, socket_fd))
+ {
sx.send_quit = FALSE;
+
+ /* 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. */
+#ifdef SUPPORT_TLS
+ if (tls_out.active >= 0)
+ {
+ int pid = fork();
+ if (pid > 0) /* parent */
+ {
+ tls_close(FALSE, FALSE);
+ (void)close(sx.inblock.sock);
+ continue_transport = NULL;
+ continue_hostname = NULL;
+ return yield;
+ }
+ else if (pid == 0) /* child */
+ {
+ smtp_proxy_tls(sx.buffer, sizeof(sx.buffer), pfd[0], sx.ob->command_timeout);
+ exim_exit(0);
+ }
+ }
+#endif
+ }
}
/* If RSET failed and there are addresses left, they get deferred. */
-
- else set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
+ else
+ set_errno(sx.first_addr, errno, msg, DEFER, FALSE, host
#ifdef EXPERIMENTAL_DSN_INFO
, sx.smtp_greeting, sx.helo_response
#endif
specified in the transports, and therefore not visible at top level, in which
case continue_more won't get set. */
-HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP(close)>>\n");
+HDEBUG(D_transport|D_acl|D_v) debug_printf_indent(" SMTP(close)>>\n");
if (sx.send_quit)
{
shutdown(sx.outblock.sock, SHUT_WR);
for (host = hostlist; host; host = host->next)
debug_printf(" %s:%d\n", host->name, host->port);
}
- if (continue_hostname) debug_printf("already connected to %s [%s]\n",
- continue_hostname, continue_host_address);
+ if (continue_hostname)
+ debug_printf("already connected to %s [%s] (on fd %d)\n",
+ continue_hostname, continue_host_address,
+ cutthrough.fd >= 0 ? cutthrough.fd : 0);
}
/* Set the flag requesting that these hosts be added to the waiting
commonly points to a configuration error, but the best action is still
to carry on for the next host. */
- if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_FAILED)
+ if (rc == HOST_FIND_AGAIN || rc == HOST_FIND_SECURITY || rc == HOST_FIND_FAILED)
{
retry_add_item(addrlist, string_sprintf("R:%s", host->name), 0);
expired = FALSE;
{
if (addr->transport_return != DEFER) continue;
addr->basic_errno = ERRNO_UNKNOWNHOST;
- addr->message =
- string_sprintf("failed to lookup IP address for %s", host->name);
+ addr->message = string_sprintf(
+ rc == HOST_FIND_SECURITY
+ ? "lookup of IP address for %s was insecure"
+ : "failed to lookup IP address for %s",
+ host->name);
}
continue;
}
host_is_expired = retry_check_address(addrlist->domain, host, pistring,
incl_ip, &retry_host_key, &retry_message_key);
- DEBUG(D_transport) debug_printf("%s [%s]%s status = %s\n", host->name,
+ DEBUG(D_transport) debug_printf("%s [%s]%s retry-status = %s\n", host->name,
(host->address == NULL)? US"" : host->address, pistring,
(host->status == hstatus_usable)? "usable" :
(host->status == hstatus_unusable)? "unusable" :
{
case hwhy_retry: hosts_retry++; break;
case hwhy_failed: hosts_fail++; break;
+ case hwhy_insecure:
case hwhy_deferred: hosts_defer++; break;
}
&& verify_check_given_host(&ob->hosts_require_tls, host) != OK
)
{
- log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted "
- "to %s [%s] (not in hosts_require_tls)", host->name, host->address);
+ log_write(0, LOG_MAIN,
+ "%s: delivering unencrypted to H=%s [%s] (not in hosts_require_tls)",
+ first_addr->message, host->name, host->address);
first_addr = prepare_addresses(addrlist, host);
rc = smtp_deliver(addrlist, thost, host_af, port, interface, tblock,
&message_defer, TRUE);
git://git.exim.org / exim.git / blobdiff