tom 2008/03/05 21:13:23 GMT
Modified files:
exim-src/src functions.h transport.c
exim-src/src/transports smtp.c smtp.h
Log:
join transport logic for DK and DKIM, making it possible to use both at the same time for signing
Revision Changes Path
1.41 +4 -7 exim/exim-src/src/functions.h
1.21 +114 -239 exim/exim-src/src/transport.c
1.39 +22 -41 exim/exim-src/src/transports/smtp.c
1.14 +1 -3 exim/exim-src/src/transports/smtp.h
Index: functions.h
===================================================================
RCS file: /home/cvs/exim/exim-src/src/functions.h,v
retrieving revision 1.40
retrieving revision 1.41
diff -u -r1.40 -r1.41
--- functions.h 17 Jan 2008 13:03:35 -0000 1.40
+++ functions.h 5 Mar 2008 21:13:23 -0000 1.41
@@ -1,4 +1,4 @@
-/* $Cambridge: exim/exim-src/src/functions.h,v 1.40 2008/01/17 13:03:35 tom Exp $ */
+/* $Cambridge: exim/exim-src/src/functions.h,v 1.41 2008/03/05 21:13:23 tom Exp $ */
/*************************************************
* Exim - an Internet mail transport agent *
@@ -83,15 +83,12 @@
extern int demime(uschar **);
#endif
extern BOOL directory_make(uschar *, uschar *, int, BOOL);
-#ifdef EXPERIMENTAL_DOMAINKEYS
-extern BOOL dk_transport_write_message(address_item *, int, int,
- int, uschar *, uschar *, uschar *, uschar *, rewrite_rule *,
- int, uschar *, uschar *, uschar *, uschar *, uschar *, uschar *);
-#endif
-#ifdef EXPERIMENTAL_DKIM
+#if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
extern BOOL dkim_transport_write_message(address_item *, int, int,
int, uschar *, uschar *, uschar *, uschar *, rewrite_rule *,
- int, uschar *, uschar *, uschar *, uschar *, uschar *, uschar *);
+ int, uschar *, uschar *, uschar *, uschar *, uschar *, uschar *,
+ uschar *, uschar *, uschar *, uschar *, uschar *, uschar *
+ );
#endif
extern dns_address *dns_address_from_rr(dns_answer *, dns_record *);
extern void dns_build_reverse(uschar *, uschar *);
Index: transport.c
===================================================================
RCS file: /home/cvs/exim/exim-src/src/transport.c,v
retrieving revision 1.20
retrieving revision 1.21
diff -u -r1.20 -r1.21
--- transport.c 28 Sep 2007 12:21:57 -0000 1.20
+++ transport.c 5 Mar 2008 21:13:23 -0000 1.21
@@ -1,4 +1,4 @@
-/* $Cambridge: exim/exim-src/src/transport.c,v 1.20 2007/09/28 12:21:57 tom Exp $ */
+/* $Cambridge: exim/exim-src/src/transport.c,v 1.21 2008/03/05 21:13:23 tom Exp $ */
/*************************************************
* Exim - an Internet mail transport agent *
@@ -941,16 +941,14 @@
}
-#ifdef EXPERIMENTAL_DOMAINKEYS
+#if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
-/**********************************************************************************
-* External interface to write the message, while signing it with domainkeys *
-**********************************************************************************/
+/***************************************************************************************************
+* External interface to write the message, while signing it with DKIM and/or Domainkeys *
+***************************************************************************************************/
/* This function is a wrapper around transport_write_message(). It is only called
- from the smtp transport if
- (1) Domainkeys support is compiled in.
- (2) The dk_private_key option on the smtp transport is set.
+ from the smtp transport if DKIM or Domainkeys support is compiled in.
The function sets up a replacement fd into a -K file, then calls the normal
function. This way, the exact bits that exim would have put "on the wire" will
end up in the file (except for TLS encapsulation, which is the very
@@ -959,199 +957,22 @@
Arguments: as for internal_transport_write_message() above, with additional
arguments:
- uschar *dk_private_key The private key to use (filename or plain data)
- uschar *dk_domain Override domain (normally NULL)
- uschar *dk_selector The selector to use.
- uschar *dk_canon The canonalization scheme to use, "simple" or "nofws"
- uschar *dk_headers Colon-separated header list to include in the signing
- process.
- uschar *dk_strict What to do if signing fails: 1/true => throw error
- 0/false => send anyway
-
-Returns: TRUE on success; FALSE (with errno) for any failure
-*/
-
-BOOL
-dk_transport_write_message(address_item *addr, int fd, int options,
- int size_limit, uschar *add_headers, uschar *remove_headers,
- uschar *check_string, uschar *escape_string, rewrite_rule *rewrite_rules,
- int rewrite_existflags, uschar *dk_private_key, uschar *dk_domain,
- uschar *dk_selector, uschar *dk_canon, uschar *dk_headers, uschar *dk_strict)
-{
- int dk_fd;
- int save_errno = 0;
- BOOL rc;
- uschar dk_spool_name[256];
- char sbuf[2048];
- int sread = 0;
- int wwritten = 0;
- uschar *dk_signature = NULL;
- off_t size = 0;
-
- (void)string_format(dk_spool_name, 256, "%s/input/%s/%s-%d-K",
- spool_directory, message_subdir, message_id, (int)getpid());
- dk_fd = Uopen(dk_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE);
- if (dk_fd < 0)
- {
- /* Can't create spool file. Ugh. */
- rc = FALSE;
- save_errno = errno;
- goto CLEANUP;
- }
-
- /* Call original function */
- rc = transport_write_message(addr, dk_fd, options,
- size_limit, add_headers, remove_headers,
- check_string, escape_string, rewrite_rules,
- rewrite_existflags);
-
- /* Save error state. We must clean up before returning. */
- if (!rc)
- {
- save_errno = errno;
- goto CLEANUP;
- }
-
- /* Rewind file and feed it to the goats^W DK lib */
- lseek(dk_fd, 0, SEEK_SET);
- dk_signature = dk_exim_sign(dk_fd,
- dk_private_key,
- dk_domain,
- dk_selector,
- dk_canon);
-
- if (dk_signature != NULL)
- {
- /* Send the signature first */
- int siglen = Ustrlen(dk_signature);
- while(siglen > 0)
- {
- #ifdef SUPPORT_TLS
- if (tls_active == fd) wwritten = tls_write(dk_signature, siglen); else
- #endif
- wwritten = write(fd,dk_signature,siglen);
- if (wwritten == -1)
- {
- /* error, bail out */
- save_errno = errno;
- rc = FALSE;
- goto CLEANUP;
- }
- siglen -= wwritten;
- dk_signature += wwritten;
- }
- }
- else if (dk_strict != NULL)
- {
- uschar *dk_strict_result = expand_string(dk_strict);
- if (dk_strict_result != NULL)
- {
- if ( (strcmpic(dk_strict,US"1") == 0) ||
- (strcmpic(dk_strict,US"true") == 0) )
- {
- save_errno = errno;
- rc = FALSE;
- goto CLEANUP;
- }
- }
- }
-
- /* Fetch file positition (the size) */
- size = lseek(dk_fd,0,SEEK_CUR);
-
- /* Rewind file */
- lseek(dk_fd, 0, SEEK_SET);
-
-#ifdef HAVE_LINUX_SENDFILE
- /* We can use sendfile() to shove the file contents
- to the socket. However only if we don't use TLS,
- in which case theres another layer of indirection
- before the data finally hits the socket. */
- if (tls_active != fd)
- {
- ssize_t copied = 0;
- off_t offset = 0;
- while((copied >= 0) && (offset<size))
- {
- copied = sendfile(fd, dk_fd, &offset, (size - offset));
- }
- if (copied < 0)
- {
- save_errno = errno;
- rc = FALSE;
- }
- goto CLEANUP;
- }
-#endif
-
- /* Send file down the original fd */
- while((sread = read(dk_fd,sbuf,2048)) > 0)
- {
- char *p = sbuf;
- /* write the chunk */
- DK_WRITE:
- #ifdef SUPPORT_TLS
- if (tls_active == fd) wwritten = tls_write(US p, sread); else
- #endif
- wwritten = write(fd,p,sread);
- if (wwritten == -1)
- {
- /* error, bail out */
- save_errno = errno;
- rc = FALSE;
- goto CLEANUP;
- }
- if (wwritten < sread)
- {
- /* short write, try again */
- p += wwritten;
- sread -= wwritten;
- goto DK_WRITE;
- }
- }
-
- if (sread == -1)
- {
- save_errno = errno;
- rc = FALSE;
- goto CLEANUP;
- }
-
- CLEANUP:
- /* unlink -K file */
- (void)close(dk_fd);
- Uunlink(dk_spool_name);
- errno = save_errno;
- return rc;
-}
-#endif
-
-
-
-#ifdef EXPERIMENTAL_DKIM
-
-/**********************************************************************************
-* External interface to write the message, while signing it with DKIM *
-**********************************************************************************/
-
-/* This function is a wrapper around transport_write_message(). It is only called
- from the smtp transport if
- (1) DKIM support is compiled in.
- (2) The dkim_private_key and dkim_domain option on the smtp transport is set.
- The function sets up a replacement fd into a -K file, then calls the normal
- function. This way, the exact bits that exim would have put "on the wire" will
- end up in the file (except for TLS encapsulation, which is the very
- very last thing). When we are done signing the file, send the
- signed message down the original fd (or TLS fd).
-
-Arguments: as for internal_transport_write_message() above, with additional
- arguments:
- uschar *dkim_private_key The private key to use (filename or plain data)
- uschar *dkim_domain The domain to use
- uschar *dkim_selector The selector to use.
- uschar *dkim_canon The canonalization scheme to use, "simple" or "relaxed"
- uschar *dkim_strict What to do if signing fails: 1/true => throw error
- 0/false => send anyway
+ uschar *dkim_private_key DKIM: The private key to use (filename or plain data)
+ uschar *dkim_domain DKIM: The domain to use
+ uschar *dkim_selector DKIM: The selector to use.
+ uschar *dkim_canon DKIM: The canonalization scheme to use, "simple" or "relaxed"
+ uschar *dkim_strict DKIM: What to do if signing fails: 1/true => throw error
+ 0/false => send anyway
+ uschar *dkim_sign_headers DKIM: List of headers that should be included in signature
+ generation
+ uschar *dk_private_key Domainkeys: The private key to use (filename or plain data)
+ uschar *dk_domain Domainkeys: Override domain (normally NULL)
+ uschar *dk_selector Domainkeys: The selector to use.
+ uschar *dk_canon Domainkeys: The canonalization scheme to use, "simple" or "nofws"
+ uschar *dk_headers Domainkeys: Colon-separated header list to include in the signing
+ process.
+ uschar *dk_strict Domainkeys: What to do if signing fails: 1/true => throw error
+ 0/false => send anyway
Returns: TRUE on success; FALSE (with errno) for any failure
*/
@@ -1161,7 +982,10 @@
int size_limit, uschar *add_headers, uschar *remove_headers,
uschar *check_string, uschar *escape_string, rewrite_rule *rewrite_rules,
int rewrite_existflags, uschar *dkim_private_key, uschar *dkim_domain,
- uschar *dkim_selector, uschar *dkim_canon, uschar *dkim_strict, uschar *dkim_sign_headers)
+ uschar *dkim_selector, uschar *dkim_canon, uschar *dkim_strict, uschar *dkim_sign_headers,
+ uschar *dk_private_key, uschar *dk_domain, uschar *dk_selector, uschar *dk_canon,
+ uschar *dk_headers, uschar *dk_strict
+ )
{
int dkim_fd;
int save_errno = 0;
@@ -1171,8 +995,18 @@
int sread = 0;
int wwritten = 0;
uschar *dkim_signature = NULL;
+ uschar *dk_signature = NULL;
off_t size = 0;
+ if ( !( ((dkim_private_key != NULL) && (dkim_domain != NULL) && (dkim_selector != NULL)) ||
+ ((dk_private_key != NULL) && (dk_selector != NULL)) ) ) {
+ /* If we can sign with neither method, just call the original function. */
+ return transport_write_message(addr, fd, options,
+ size_limit, add_headers, remove_headers,
+ check_string, escape_string, rewrite_rules,
+ rewrite_existflags);
+ }
+
(void)string_format(dkim_spool_name, 256, "%s/input/%s/%s-%d-K",
spool_directory, message_subdir, message_id, (int)getpid());
dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE);
@@ -1197,50 +1031,91 @@
goto CLEANUP;
}
- /* Rewind file and feed it to the goats^W DKIM lib */
- lseek(dkim_fd, 0, SEEK_SET);
- dkim_signature = dkim_exim_sign(dkim_fd,
- dkim_private_key,
- dkim_domain,
- dkim_selector,
- dkim_canon,
- dkim_sign_headers);
-
- if (dkim_signature != NULL)
- {
- /* Send the signature first */
- int siglen = Ustrlen(dkim_signature);
- while(siglen > 0)
- {
- #ifdef SUPPORT_TLS
- if (tls_active == fd) wwritten = tls_write(dkim_signature, siglen); else
- #endif
- wwritten = write(fd,dkim_signature,siglen);
- if (wwritten == -1)
- {
- /* error, bail out */
- save_errno = errno;
- rc = FALSE;
- goto CLEANUP;
+
+ #ifdef EXPERIMENTAL_DKIM
+ if ( (dkim_private_key != NULL) && (dkim_domain != NULL) && (dkim_selector != NULL) ) {
+ /* Rewind file and feed it to the goats^W DKIM lib */
+ lseek(dkim_fd, 0, SEEK_SET);
+ dkim_signature = dkim_exim_sign(dkim_fd,
+ dkim_private_key,
+ dkim_domain,
+ dkim_selector,
+ dkim_canon,
+ dkim_sign_headers);
+ if (dkim_signature == NULL) {
+ if (dkim_strict != NULL) {
+ uschar *dkim_strict_result = expand_string(dkim_strict);
+ if (dkim_strict_result != NULL) {
+ if ( (strcmpic(dkim_strict,US"1") == 0) ||
+ (strcmpic(dkim_strict,US"true") == 0) ) {
+ save_errno = errno;
+ rc = FALSE;
+ goto CLEANUP;
+ }
}
- siglen -= wwritten;
- dkim_signature += wwritten;
}
}
- else if (dkim_strict != NULL)
- {
- uschar *dkim_strict_result = expand_string(dkim_strict);
- if (dkim_strict_result != NULL)
- {
- if ( (strcmpic(dkim_strict,US"1") == 0) ||
- (strcmpic(dkim_strict,US"true") == 0) )
- {
- save_errno = errno;
- rc = FALSE;
- goto CLEANUP;
+ else {
+ int siglen = Ustrlen(dkim_signature);
+ while(siglen > 0) {
+ #ifdef SUPPORT_TLS
+ if (tls_active == fd) wwritten = tls_write(dkim_signature, siglen); else
+ #endif
+ wwritten = write(fd,dkim_signature,siglen);
+ if (wwritten == -1) {
+ /* error, bail out */
+ save_errno = errno;
+ rc = FALSE;
+ goto CLEANUP;
+ }
+ siglen -= wwritten;
+ dkim_signature += wwritten;
+ }
+ }
+ }
+ #endif
+
+ #ifdef EXPERIMENTAL_DOMAINKEYS
+ if ( (dk_private_key != NULL) && (dk_selector != NULL) ) {
+ /* Rewind file and feed it to the goats^W DK lib */
+ lseek(dkim_fd, 0, SEEK_SET);
+ dk_signature = dk_exim_sign(dkim_fd,
+ dk_private_key,
+ dk_domain,
+ dk_selector,
+ dk_canon);
+ if (dk_signature == NULL) {
+ if (dk_strict != NULL) {
+ uschar *dk_strict_result = expand_string(dk_strict);
+ if (dk_strict_result != NULL) {
+ if ( (strcmpic(dk_strict,US"1") == 0) ||
+ (strcmpic(dk_strict,US"true") == 0) ) {
+ save_errno = errno;
+ rc = FALSE;
+ goto CLEANUP;
+ }
}
}
}
+ else {
+ int siglen = Ustrlen(dk_signature);
+ while(siglen > 0) {
+ #ifdef SUPPORT_TLS
+ if (tls_active == fd) wwritten = tls_write(dk_signature, siglen); else
+ #endif
+ wwritten = write(fd,dk_signature,siglen);
+ if (wwritten == -1) {
+ /* error, bail out */
+ save_errno = errno;
+ rc = FALSE;
+ goto CLEANUP;
+ }
+ siglen -= wwritten;
+ dk_signature += wwritten;
+ }
+ }
+ }
+ #endif
/* Fetch file positition (the size) */
size = lseek(dkim_fd,0,SEEK_CUR);
Index: smtp.c
===================================================================
RCS file: /home/cvs/exim/exim-src/src/transports/smtp.c,v
retrieving revision 1.38
retrieving revision 1.39
diff -u -r1.38 -r1.39
--- smtp.c 28 Sep 2007 12:21:57 -0000 1.38
+++ smtp.c 5 Mar 2008 21:13:23 -0000 1.39
@@ -1,4 +1,4 @@
-/* $Cambridge: exim/exim-src/src/transports/smtp.c,v 1.38 2007/09/28 12:21:57 tom Exp $ */
+/* $Cambridge: exim/exim-src/src/transports/smtp.c,v 1.39 2008/03/05 21:13:23 tom Exp $ */
/*************************************************
* Exim - an Internet mail transport agent *
@@ -39,7 +39,7 @@
(void *)offsetof(smtp_transport_options_block, data_timeout) },
{ "delay_after_cutoff", opt_bool,
(void *)offsetof(smtp_transport_options_block, delay_after_cutoff) },
-#ifdef EXPERIMENTAL_DOMAINKEYS
+ #if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
{ "dk_canon", opt_stringptr,
(void *)offsetof(smtp_transport_options_block, dk_canon) },
{ "dk_domain", opt_stringptr,
@@ -52,8 +52,6 @@
(void *)offsetof(smtp_transport_options_block, dk_selector) },
{ "dk_strict", opt_stringptr,
(void *)offsetof(smtp_transport_options_block, dk_strict) },
-#endif
-#ifdef EXPERIMENTAL_DKIM
{ "dkim_canon", opt_stringptr,
(void *)offsetof(smtp_transport_options_block, dkim_canon) },
{ "dkim_domain", opt_stringptr,
@@ -66,7 +64,7 @@
(void *)offsetof(smtp_transport_options_block, dkim_sign_headers) },
{ "dkim_strict", opt_stringptr,
(void *)offsetof(smtp_transport_options_block, dkim_strict) },
-#endif
+ #endif
{ "dns_qualify_single", opt_bool,
(void *)offsetof(smtp_transport_options_block, dns_qualify_single) },
{ "dns_search_parents", opt_bool,
@@ -209,15 +207,13 @@
NULL, /* tls_verify_certificates */
TRUE /* tls_tempfail_tryclear */
#endif
- #ifdef EXPERIMENTAL_DOMAINKEYS
+ #if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
,NULL, /* dk_canon */
NULL, /* dk_domain */
NULL, /* dk_headers */
NULL, /* dk_private_key */
NULL, /* dk_selector */
NULL /* dk_strict */
- #endif
- #ifdef EXPERIMENTAL_DKIM
,NULL, /* dkim_canon */
NULL, /* dkim_domain */
NULL, /* dkim_private_key */
@@ -1595,40 +1591,24 @@
DEBUG(D_transport|D_v)
debug_printf(" SMTP>> writing message and terminating \".\"\n");
transport_count = 0;
-#ifdef EXPERIMENTAL_DOMAINKEYS
- if ( (ob->dk_private_key != NULL) && (ob->dk_selector != NULL) )
- ok = dk_transport_write_message(addrlist, inblock.sock,
- topt_use_crlf | topt_end_dot | topt_escape_headers |
- (tblock->body_only? topt_no_headers : 0) |
- (tblock->headers_only? topt_no_body : 0) |
- (tblock->return_path_add? topt_add_return_path : 0) |
- (tblock->delivery_date_add? topt_add_delivery_date : 0) |
- (tblock->envelope_to_add? topt_add_envelope_to : 0),
- 0, /* No size limit */
- tblock->add_headers, tblock->remove_headers,
- US".", US"..", /* Escaping strings */
- tblock->rewrite_rules, tblock->rewrite_existflags,
- ob->dk_private_key, ob->dk_domain, ob->dk_selector,
- ob->dk_canon, ob->dk_headers, ob->dk_strict);
- else
-#endif
-#ifdef EXPERIMENTAL_DKIM
- if ( (ob->dkim_private_key != NULL) && (ob->dkim_domain != NULL) && (ob->dkim_selector != NULL) )
- ok = dkim_transport_write_message(addrlist, inblock.sock,
- topt_use_crlf | topt_end_dot | topt_escape_headers |
- (tblock->body_only? topt_no_headers : 0) |
- (tblock->headers_only? topt_no_body : 0) |
- (tblock->return_path_add? topt_add_return_path : 0) |
- (tblock->delivery_date_add? topt_add_delivery_date : 0) |
- (tblock->envelope_to_add? topt_add_envelope_to : 0),
- 0, /* No size limit */
- tblock->add_headers, tblock->remove_headers,
- US".", US"..", /* Escaping strings */
- tblock->rewrite_rules, tblock->rewrite_existflags,
- ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
- ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers);
- else
-#endif
+#if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
+ ok = dkim_transport_write_message(addrlist, inblock.sock,
+ topt_use_crlf | topt_end_dot | topt_escape_headers |
+ (tblock->body_only? topt_no_headers : 0) |
+ (tblock->headers_only? topt_no_body : 0) |
+ (tblock->return_path_add? topt_add_return_path : 0) |
+ (tblock->delivery_date_add? topt_add_delivery_date : 0) |
+ (tblock->envelope_to_add? topt_add_envelope_to : 0),
+ 0, /* No size limit */
+ tblock->add_headers, tblock->remove_headers,
+ US".", US"..", /* Escaping strings */
+ tblock->rewrite_rules, tblock->rewrite_existflags,
+ ob->dkim_private_key, ob->dkim_domain, ob->dkim_selector,
+ ob->dkim_canon, ob->dkim_strict, ob->dkim_sign_headers,
+ ob->dk_private_key, ob->dk_domain, ob->dk_selector,
+ ob->dk_canon, ob->dk_headers, ob->dk_strict
+ );
+#else
ok = transport_write_message(addrlist, inblock.sock,
topt_use_crlf | topt_end_dot | topt_escape_headers |
(tblock->body_only? topt_no_headers : 0) |
@@ -1640,6 +1620,7 @@
tblock->add_headers, tblock->remove_headers,
US".", US"..", /* Escaping strings */
tblock->rewrite_rules, tblock->rewrite_existflags);
+#endif
/* transport_write_message() uses write() because it is called from other
places to write to non-sockets. This means that under some OS (e.g. Solaris)
Index: smtp.h
===================================================================
RCS file: /home/cvs/exim/exim-src/src/transports/smtp.h,v
retrieving revision 1.13
retrieving revision 1.14
diff -u -r1.13 -r1.14
--- smtp.h 28 Sep 2007 12:21:57 -0000 1.13
+++ smtp.h 5 Mar 2008 21:13:23 -0000 1.14
@@ -1,4 +1,4 @@
-/* $Cambridge: exim/exim-src/src/transports/smtp.h,v 1.13 2007/09/28 12:21:57 tom Exp $ */
+/* $Cambridge: exim/exim-src/src/transports/smtp.h,v 1.14 2008/03/05 21:13:23 tom Exp $ */
/*************************************************
* Exim - an Internet mail transport agent *
@@ -57,15 +57,13 @@
uschar *tls_verify_certificates;
BOOL tls_tempfail_tryclear;
#endif
- #ifdef EXPERIMENTAL_DOMAINKEYS
+ #if (defined EXPERIMENTAL_DOMAINKEYS) || (defined EXPERIMENTAL_DKIM)
uschar *dk_domain;
uschar *dk_private_key;
uschar *dk_selector;
uschar *dk_canon;
uschar *dk_headers;
uschar *dk_strict;
- #endif
- #ifdef EXPERIMENTAL_DKIM
uschar *dkim_domain;
uschar *dkim_private_key;
uschar *dkim_selector;
