extern pdkim_ctx * dkim_verify_ctx;
extern pdkim_ctx dkim_sign_ctx;
+#define ARC_SIGN_OPT_TSTAMP BIT(0)
+
/******************************************************************************/
typedef struct hdr_rlist {
int canon_head, canon_body;
long bodylen;
+if (!ams->c.data) ams->c.data = US"simple"; /* RFC 6376 (DKIM) default */
pdkim_cstring_to_canons(ams->c.data, ams->c.len, &canon_head, &canon_body);
bodylen = ams->l.data
? strtol(CS string_copyn(ams->l.data, ams->l.len), NULL, 10) : -1;
|| arc_cv_match(as->hdr_as, US"fail")
)
{
- arc_state_reason = string_sprintf("i=%d fail"
+ arc_state_reason = string_sprintf("i=%d"
" (cv, sequence or missing header)", as->instance);
- DEBUG(D_acl) debug_printf("ARC %s\n", arc_state_reason);
- ret = US"fail";
+ DEBUG(D_acl) debug_printf("ARC chain fail at %s\n", arc_state_reason);
+ return US"fail";
}
/* Evaluate the oldest-pass AMS validation while we're here.
/* Walk the given headers strings identifying each header, and construct
-a reverse-order list. Also parse ARC-chain headers and build the chain
-struct, retaining pointers into the string.
+a reverse-order list.
*/
static hdr_rlist *
if ( (errstr = exim_dkim_signing_init(privkey, &sctx))
|| (errstr = exim_dkim_sign(&sctx, hm, &hhash, sig)))
{
- log_write(0, LOG_MAIN|LOG_PANIC, "ARC: %s signing: %s\n", why, errstr);
+ log_write(0, LOG_MAIN, "ARC: %s signing: %s\n", why, errstr);
return FALSE;
}
return TRUE;
static gstring *
arc_sign_append_ams(gstring * g, arc_ctx * ctx, int instance,
const uschar * identity, const uschar * selector, blob * bodyhash,
- hdr_rlist * rheaders, const uschar * privkey)
+ hdr_rlist * rheaders, const uschar * privkey, unsigned options)
{
uschar * s;
gstring * hdata = NULL;
/* Construct the to-be-signed AMS pseudo-header: everything but the sig. */
ams_off = g->ptr;
-g = string_append(g, 10,
+g = string_append(g, 7,
ARC_HDR_AMS,
US" i=", string_sprintf("%d", instance),
US"; a=rsa-sha256; c=relaxed; d=", identity, /*XXX hardwired */
- US"; s=", selector,
+ US"; s=", selector);
+if (options & ARC_SIGN_OPT_TSTAMP)
+ g = string_append(g, 2,
+ US"; t=", string_sprintf("%lu", (u_long)time(NULL)));
+g = string_append(g, 3,
US";\r\n\tbh=", pdkim_encode_base64(bodyhash),
US";\r\n\th=");
static gstring *
arc_sign_prepend_as(gstring * arcset_interim, arc_ctx * ctx,
int instance, const uschar * identity, const uschar * selector, blob * ar,
- const uschar * privkey)
+ const uschar * privkey, unsigned options)
{
gstring * arcset;
arc_set * as;
/* Construct the AS except for the signature */
-arcset = string_append(NULL, 10,
+arcset = string_append(NULL, 9,
ARC_HDR_AS,
US" i=", string_sprintf("%d", instance),
US"; cv=", status,
US"; a=rsa-sha256; d=", identity, /*XXX hardwired */
- US"; s=", selector, /*XXX same as AMS */
+ US"; s=", selector); /*XXX same as AMS */
+if (options & ARC_SIGN_OPT_TSTAMP)
+ arcset = string_append(arcset, 2,
+ US"; t=", string_sprintf("%lu", (u_long)time(NULL)));
+arcset = string_cat(arcset,
US";\r\n\t b=;");
h->slen = arcset->ptr;
+void
+arc_sign_init(void)
+{
+memset(&arc_sign_ctx, 0, sizeof(arc_sign_ctx));
+}
+
+
+
/* A "normal" header line, identified by DKIM processing. These arrive before
the call to arc_sign(), which carries any newly-created DKIM headers - and
those go textually before the normal ones in the message.
message body for us so long as we requested a hash previously.
Arguments:
- signspec Three-element colon-sep list: identity, selector, privkey
+ signspec Three-element colon-sep list: identity, selector, privkey.
+ Optional fourth element: comma-sep list of options.
Already expanded
sigheaders Any signature headers already generated, eg. by DKIM, or NULL
errstr Error string
gstring *
arc_sign(const uschar * signspec, gstring * sigheaders, uschar ** errstr)
{
-const uschar * identity, * selector, * privkey;
+const uschar * identity, * selector, * privkey, * opts, * s;
+unsigned options = 0;
int sep = 0;
header_line * headers;
hdr_rlist * rheaders;
if ( !*identity | !*selector
|| !(privkey = string_nextinlist(&signspec, &sep, NULL, 0)) || !*privkey)
{
- log_write(0, LOG_MAIN|LOG_PANIC, "ARC: bad signing-specification (%s)",
+ log_write(0, LOG_MAIN, "ARC: bad signing-specification (%s)",
!*identity ? "identity" : !*selector ? "selector" : "private-key");
- return NULL;
+ return sigheaders ? sigheaders : string_get(0);
}
if (*privkey == '/' && !(privkey = expand_file_big_buffer(privkey)))
- return NULL;
+ return sigheaders ? sigheaders : string_get(0);
-DEBUG(D_transport) debug_printf("ARC: sign for %s\n", identity);
+if ((opts = string_nextinlist(&signspec, &sep, NULL, 0)))
+ {
+ int osep = ',';
+ while ((s = string_nextinlist(&opts, &osep, NULL, 0)))
+ if (Ustrcmp(s, "timestamps") == 0)
+ options |= ARC_SIGN_OPT_TSTAMP;
+ }
-/*
-- scan headers for existing ARC chain & A-R (with matching system-identfier)
- - paniclog & skip on problems (no A-R)
-*/
+DEBUG(D_transport) debug_printf("ARC: sign for %s\n", identity);
-/* Make an rlist of any new DKIM headers, then add the "normals" rlist to it */
+/* Make an rlist of any new DKIM headers, then add the "normals" rlist to it.
+Then scan the list for an A-R header. */
string_from_gstring(sigheaders);
if ((rheaders = arc_sign_scan_headers(&arc_sign_ctx, sigheaders)))
}
else
rheaders = headers_rlist;
+
/* Finally, build a normal-order headers list */
/*XXX only needed for hunt-the-AR? */
-{
-header_line * hnext = NULL;
-for (; rheaders; hnext = rheaders->h, rheaders = rheaders->prev)
- rheaders->h->next = hnext;
-headers = hnext;
-}
-
-instance = arc_sign_ctx.arcset_chain_last ? arc_sign_ctx.arcset_chain_last->instance + 1 : 1;
+ {
+ header_line * hnext = NULL;
+ for (; rheaders; hnext = rheaders->h, rheaders = rheaders->prev)
+ rheaders->h->next = hnext;
+ headers = hnext;
+ }
if (!(arc_sign_find_ar(headers, identity, &ar)))
{
- log_write(0, LOG_MAIN|LOG_PANIC, "ARC: no Authentication-Results header for signing");
+ log_write(0, LOG_MAIN, "ARC: no Authentication-Results header for signing");
return sigheaders ? sigheaders : string_get(0);
}
+/* We previously built the data-struct for the existing ARC chain, if any, using a headers
+feed from the DKIM module. Use that to give the instance number for the ARC set we are
+about to build. */
+
+DEBUG(D_transport)
+ if (arc_sign_ctx.arcset_chain_last)
+ debug_printf("ARC: existing chain highest instance: %d\n",
+ arc_sign_ctx.arcset_chain_last->instance);
+ else
+ debug_printf("ARC: no existing chain\n");
+
+instance = arc_sign_ctx.arcset_chain_last ? arc_sign_ctx.arcset_chain_last->instance + 1 : 1;
+
/*
- Generate AAR
- copy the A-R; prepend i= & identity
b = arc_ams_setup_sign_bodyhash();
g = arc_sign_append_ams(g, &arc_sign_ctx, instance, identity, selector,
- &b->bh, headers_rlist, privkey);
+ &b->bh, headers_rlist, privkey, options);
/*
- Generate AS
including self (but with an empty b= in self)
*/
-g = arc_sign_prepend_as(g, &arc_sign_ctx, instance, identity, selector, &ar, privkey);
+g = arc_sign_prepend_as(g, &arc_sign_ctx, instance, identity, selector, &ar,
+ privkey, options);
/* Finally, append the dkim headers and return the lot. */
if (sender_host_address)
g = string_append(g, 2, US" smtp.client-ip=", sender_host_address);
}
+ else if (arc_state_reason)
+ g = string_append(g, 3, US" (", arc_state_reason, US")");
DEBUG(D_acl) debug_printf("ARC: authres '%.*s'\n",
g->ptr - start - 3, g->s + start + 3);
}
git://git.exim.org / exim.git / blobdiff