Try to fix Solaris build

[users/jgh/exim.git] / src / src / dkim.c

diff --git a/src/src/dkim.c b/src/src/dkim.c
index 41540b39d396d71a300394c27baa764ff33d491a..5c9d2279e165767715385013862a330b81023c9d 100644 (file)
--- a/src/src/dkim.c
+++ b/src/src/dkim.c
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 

-/* Copyright (c) University of Cambridge, 1995 - 2017 */
+/* Copyright (c) University of Cambridge, 1995 - 2018 */

 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Code for DKIM support. Other DKIM relevant code is in
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Code for DKIM support. Other DKIM relevant code is in


@@ -18,7 +18,7 @@
 #  include "macro_predef.h"
 
 void
 #  include "macro_predef.h"
 
 void

-dkim_params(void)
+params_dkim(void)

 {
 builtin_macro_create_var(US"_DKIM_SIGN_HEADERS", US PDKIM_DEFAULT_SIGN_HEADERS);
 }
 {
 builtin_macro_create_var(US"_DKIM_SIGN_HEADERS", US PDKIM_DEFAULT_SIGN_HEADERS);
 }


@@ -26,63 +26,77 @@ builtin_macro_create_var(US"_DKIM_SIGN_HEADERS", US PDKIM_DEFAULT_SIGN_HEADERS);
 
 
 
 
 
 

+pdkim_ctx dkim_sign_ctx;

 
 int dkim_verify_oldpool;
 pdkim_ctx *dkim_verify_ctx = NULL;
 
 int dkim_verify_oldpool;
 pdkim_ctx *dkim_verify_ctx = NULL;

-pdkim_signature *dkim_signatures = NULL;

 pdkim_signature *dkim_cur_sig = NULL;
 static const uschar * dkim_collect_error = NULL;
 
 pdkim_signature *dkim_cur_sig = NULL;
 static const uschar * dkim_collect_error = NULL;
 

+#define DKIM_MAX_SIGNATURES 20

 
 
 
 

-/*XXX the caller only uses the first record if we return multiple.
-Could we hand back an allocated string?
+
+/* Look up the DKIM record in DNS for the given hostname.
+Will use the first found if there are multiple.
+The return string is tainted, having come from off-site.

 */
 
 */
 

-static int
-dkim_exim_query_dns_txt(char *name, char *answer)
+uschar *
+dkim_exim_query_dns_txt(const uschar * name)

 {
 {

-dns_answer dnsa;
+dns_answer * dnsa = store_get_dns_answer();

 dns_scan dnss;
 dns_scan dnss;

-dns_record *rr;
+rmark reset_point = store_mark();
+gstring * g = NULL;

 
 lookup_dnssec_authenticated = NULL;
 
 lookup_dnssec_authenticated = NULL;

-if (dns_lookup(&dnsa, US name, T_TXT, NULL) != DNS_SUCCEED)
-  return PDKIM_FAIL;   /*XXX better error detail?  logging? */
+if (dns_lookup(dnsa, name, T_TXT, NULL) != DNS_SUCCEED)
+  return NULL; /*XXX better error detail?  logging? */

 
 /* Search for TXT record */
 
 
 /* Search for TXT record */
 

-for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
+for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS);

      rr;
      rr;

-     rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
+     rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))

   if (rr->type == T_TXT)
     {
     int rr_offset = 0;
   if (rr->type == T_TXT)
     {
     int rr_offset = 0;

-    int answer_offset = 0;

 
     /* Copy record content to the answer buffer */
 
     while (rr_offset < rr->size)
       {
       uschar len = rr->data[rr_offset++];
 
     /* Copy record content to the answer buffer */
 
     while (rr_offset < rr->size)
       {
       uschar len = rr->data[rr_offset++];

-      snprintf(answer + answer_offset,
-               PDKIM_DNS_TXT_MAX_RECLEN - answer_offset,
-               "%.*s", (int)len, CS  (rr->data + rr_offset));
+
+      g = string_catn(g, US(rr->data + rr_offset), len);
+      if (g->ptr >= PDKIM_DNS_TXT_MAX_RECLEN)
+       goto bad;
+

       rr_offset += len;
       rr_offset += len;

-      answer_offset += len;
-      if (answer_offset >= PDKIM_DNS_TXT_MAX_RECLEN)
-       return PDKIM_FAIL;      /*XXX better error detail?  logging? */

       }
       }

-    return PDKIM_OK;
+
+    /* check if this looks like a DKIM record */
+    if (Ustrncmp(g->s, "v=", 2) != 0 || strncasecmp(CS g->s, "v=dkim", 6) == 0)
+      {
+      gstring_release_unused(g);
+      return string_from_gstring(g);
+      }
+
+    if (g) g->ptr = 0;         /* overwrite previous record */

     }
 
     }
 

-return PDKIM_FAIL;     /*XXX better error detail?  logging? */
+bad:
+store_reset(reset_point);
+return NULL;   /*XXX better error detail?  logging? */

 }
 
 
 void
 dkim_exim_init(void)
 {
 }
 
 
 void
 dkim_exim_init(void)
 {

+if (f.dkim_init_done) return;
+f.dkim_init_done = TRUE;

 pdkim_init();
 }
 
 pdkim_init();
 }
 


@@ -91,6 +105,8 @@ pdkim_init();
 void
 dkim_exim_verify_init(BOOL dot_stuffing)
 {
 void
 dkim_exim_verify_init(BOOL dot_stuffing)
 {

+dkim_exim_init();
+

 /* There is a store-reset between header & body reception
 so cannot use the main pool. Any allocs done by Exim
 memory-handling must use the perm pool. */
 /* There is a store-reset between header & body reception
 so cannot use the main pool. Any allocs done by Exim
 memory-handling must use the perm pool. */


@@ -106,7 +122,7 @@ if (dkim_verify_ctx)
 /* Create new context */
 
 dkim_verify_ctx = pdkim_init_verify(&dkim_exim_query_dns_txt, dot_stuffing);
 /* Create new context */
 
 dkim_verify_ctx = pdkim_init_verify(&dkim_exim_query_dns_txt, dot_stuffing);

-dkim_collect_input = !!dkim_verify_ctx;
+dkim_collect_input = dkim_verify_ctx ? DKIM_MAX_SIGNATURES : 0;

 dkim_collect_error = NULL;
 
 /* Start feed up with any cached data */
 dkim_collect_error = NULL;
 
 /* Start feed up with any cached data */


@@ -128,146 +144,191 @@ if (  dkim_collect_input
   dkim_collect_error = pdkim_errstr(rc);
   log_write(0, LOG_MAIN,
             "DKIM: validation error: %.100s", dkim_collect_error);
   dkim_collect_error = pdkim_errstr(rc);
   log_write(0, LOG_MAIN,
             "DKIM: validation error: %.100s", dkim_collect_error);

-  dkim_collect_input = FALSE;
+  dkim_collect_input = 0;

   }
 store_pool = dkim_verify_oldpool;
 }
 
 
   }
 store_pool = dkim_verify_oldpool;
 }
 
 

-void
-dkim_exim_verify_finish(void)
+/* Log the result for the given signature */
+static void
+dkim_exim_verify_log_sig(pdkim_signature * sig)

 {
 {

-pdkim_signature * sig = NULL;
-int rc;
-gstring * g = NULL;
-const uschar * errstr;
-
-store_pool = POOL_PERM;
-
-/* Delete eventual previous signature chain */
-
-dkim_signers = NULL;
-dkim_signatures = NULL;
-
-if (dkim_collect_error)
-  {
-  log_write(0, LOG_MAIN,
-      "DKIM: Error during validation, disabling signature verification: %.100s",
-      dkim_collect_error);
-  dkim_disable_verify = TRUE;
-  goto out;
+gstring * logmsg;
+uschar * s;
+
+if (!sig) return;
+
+/* Remember the domain for the first pass result */
+
+if (  !dkim_verify_overall
+   && dkim_verify_status
+      ? Ustrcmp(dkim_verify_status, US"pass") == 0
+      : sig->verify_status == PDKIM_VERIFY_PASS
+   )
+  dkim_verify_overall = string_copy(sig->domain);
+
+/* Rewrite the sig result if the ACL overrode it.  This is only
+needed because the DMARC code (sigh) peeks at the dkim sigs.
+Mark the sig for this having been done. */
+
+if (  dkim_verify_status
+   && (  dkim_verify_status != dkim_exim_expand_query(DKIM_VERIFY_STATUS)
+      || dkim_verify_reason != dkim_exim_expand_query(DKIM_VERIFY_REASON)
+   )  )
+  {                    /* overridden by ACL */
+  sig->verify_ext_status = -1;
+  if (Ustrcmp(dkim_verify_status, US"fail") == 0)
+    sig->verify_status = PDKIM_VERIFY_POLICY | PDKIM_VERIFY_FAIL;
+  else if (Ustrcmp(dkim_verify_status, US"invalid") == 0)
+    sig->verify_status = PDKIM_VERIFY_POLICY | PDKIM_VERIFY_INVALID;
+  else if (Ustrcmp(dkim_verify_status, US"none") == 0)
+    sig->verify_status = PDKIM_VERIFY_POLICY | PDKIM_VERIFY_NONE;
+  else if (Ustrcmp(dkim_verify_status, US"pass") == 0)
+    sig->verify_status = PDKIM_VERIFY_POLICY | PDKIM_VERIFY_PASS;
+  else
+    sig->verify_status = -1;

   }
 
   }
 

-dkim_collect_input = FALSE;
-
-/* Finish DKIM operation and fetch link to signatures chain */
-
-rc = pdkim_feed_finish(dkim_verify_ctx, &dkim_signatures, &errstr);
-if (rc != PDKIM_OK)
-  {
-  log_write(0, LOG_MAIN, "DKIM: validation error: %.100s%s%s", pdkim_errstr(rc),
-           errstr ? ": " : "", errstr ? errstr : US"");
-  goto out;
-  }
-
-for (sig = dkim_signatures; sig; sig = sig->next)
-  {
-  uschar * s;
-  gstring * logmsg;
-
-  /* Log a line for each signature */
-
-  if (!(s = sig->domain)) s = US"<UNSET>";
-  logmsg = string_append(NULL, 2, "d=", s);
-  if (!(s = sig->selector)) s = US"<UNSET>";
-  logmsg = string_append(logmsg, 2, " s=", s);
-  logmsg = string_append(logmsg, 7, 
-       " c=", sig->canon_headers == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
-       "/",   sig->canon_body    == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
-       " a=", dkim_sig_to_a_tag(sig),
-       string_sprintf(" b=" SIZE_T_FMT,
-                       (int)sig->sighash.len > -1 ? sig->sighash.len * 8 : 0));
-  if ((s= sig->identity)) logmsg = string_append(logmsg, 2, " i=", s);
-  if (sig->created > 0) logmsg = string_cat(logmsg,
-                                     string_sprintf(" t=%lu", sig->created));
-  if (sig->expires > 0) logmsg = string_cat(logmsg,
-                                     string_sprintf(" x=%lu", sig->expires));
-  if (sig->bodylength > -1) logmsg = string_cat(logmsg,
-                                     string_sprintf(" l=%lu", sig->bodylength));
-
+if (!LOGGING(dkim_verbose)) return;
+
+
+logmsg = string_catn(NULL, US"DKIM: ", 6);
+if (!(s = sig->domain)) s = US"<UNSET>";
+logmsg = string_append(logmsg, 2, "d=", s);
+if (!(s = sig->selector)) s = US"<UNSET>";
+logmsg = string_append(logmsg, 2, " s=", s);
+logmsg = string_fmt_append(logmsg, " c=%s/%s a=%s b=" SIZE_T_FMT,
+         sig->canon_headers == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
+         sig->canon_body    == PDKIM_CANON_SIMPLE ? "simple" : "relaxed",
+         dkim_sig_to_a_tag(sig),
+         (int)sig->sighash.len > -1 ? sig->sighash.len * 8 : (size_t)0);
+if ((s= sig->identity)) logmsg = string_append(logmsg, 2, " i=", s);
+if (sig->created > 0) logmsg = string_fmt_append(logmsg, " t=%lu",
+                                   sig->created);
+if (sig->expires > 0) logmsg = string_fmt_append(logmsg, " x=%lu",
+                                   sig->expires);
+if (sig->bodylength > -1) logmsg = string_fmt_append(logmsg, " l=%lu",
+                                   sig->bodylength);
+
+if (sig->verify_status & PDKIM_VERIFY_POLICY)
+  logmsg = string_append(logmsg, 5,
+           US" [", dkim_verify_status, US" - ", dkim_verify_reason, US"]");
+else

   switch (sig->verify_status)
     {
     case PDKIM_VERIFY_NONE:
   switch (sig->verify_status)
     {
     case PDKIM_VERIFY_NONE:

-      logmsg = string_cat(logmsg, " [not verified]");
+      logmsg = string_cat(logmsg, US" [not verified]");

       break;
 
     case PDKIM_VERIFY_INVALID:
       break;
 
     case PDKIM_VERIFY_INVALID:

-      logmsg = string_cat(logmsg, " [invalid - ");
+      logmsg = string_cat(logmsg, US" [invalid - ");

       switch (sig->verify_ext_status)
        {
        case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE:
          logmsg = string_cat(logmsg,
       switch (sig->verify_ext_status)
        {
        case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE:
          logmsg = string_cat(logmsg,

-                       "public key record (currently?) unavailable]");
+                       US"public key record (currently?) unavailable]");

          break;
 
        case PDKIM_VERIFY_INVALID_BUFFER_SIZE:
          break;
 
        case PDKIM_VERIFY_INVALID_BUFFER_SIZE:

-         logmsg = string_cat(logmsg, "overlong public key record]");
+         logmsg = string_cat(logmsg, US"overlong public key record]");

          break;
 
        case PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD:
        case PDKIM_VERIFY_INVALID_PUBKEY_IMPORT:
          break;
 
        case PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD:
        case PDKIM_VERIFY_INVALID_PUBKEY_IMPORT:

-         logmsg = string_cat(logmsg, "syntax error in public key record]");
+         logmsg = string_cat(logmsg, US"syntax error in public key record]");

          break;
 
          break;
 

-        case PDKIM_VERIFY_INVALID_SIGNATURE_ERROR:
-          logmsg = string_cat(logmsg, "signature tag missing or invalid]");
-          break;
+       case PDKIM_VERIFY_INVALID_SIGNATURE_ERROR:
+         logmsg = string_cat(logmsg, US"signature tag missing or invalid]");
+         break;

 
 

-        case PDKIM_VERIFY_INVALID_DKIM_VERSION:
-          logmsg = string_cat(logmsg, "unsupported DKIM version]");
-          break;
+       case PDKIM_VERIFY_INVALID_DKIM_VERSION:
+         logmsg = string_cat(logmsg, US"unsupported DKIM version]");
+         break;

 
        default:
 
        default:

-         logmsg = string_cat(logmsg, "unspecified problem]");
+         logmsg = string_cat(logmsg, US"unspecified problem]");

        }
       break;
 
     case PDKIM_VERIFY_FAIL:
        }
       break;
 
     case PDKIM_VERIFY_FAIL:

-      logmsg =
-       string_cat(logmsg, " [verification failed - ");
+      logmsg = string_cat(logmsg, US" [verification failed - ");

       switch (sig->verify_ext_status)
        {
        case PDKIM_VERIFY_FAIL_BODY:
          logmsg = string_cat(logmsg,
       switch (sig->verify_ext_status)
        {
        case PDKIM_VERIFY_FAIL_BODY:
          logmsg = string_cat(logmsg,

-                      "body hash mismatch (body probably modified in transit)]");
+              US"body hash mismatch (body probably modified in transit)]");

          break;
 
        case PDKIM_VERIFY_FAIL_MESSAGE:
          logmsg = string_cat(logmsg,
          break;
 
        case PDKIM_VERIFY_FAIL_MESSAGE:
          logmsg = string_cat(logmsg,

-                      "signature did not verify (headers probably modified in transit)]");
-       break;
+               US"signature did not verify "
+               "(headers probably modified in transit)]");
+         break;

 
        default:
 
        default:

-         logmsg = string_cat(logmsg, "unspecified reason]");
+         logmsg = string_cat(logmsg, US"unspecified reason]");

        }
       break;
 
     case PDKIM_VERIFY_PASS:
        }
       break;
 
     case PDKIM_VERIFY_PASS:

-      logmsg = string_cat(logmsg, " [verification succeeded]");
+      logmsg = string_cat(logmsg, US" [verification succeeded]");

       break;
     }
 
       break;
     }
 

-  log_write(0, LOG_MAIN, "DKIM: %s", string_from_gstring(logmsg));
+log_write(0, LOG_MAIN, "%s", string_from_gstring(logmsg));
+return;
+}
+
+
+/* Log a line for each signature */
+void
+dkim_exim_verify_log_all(void)
+{
+for (pdkim_signature * sig = dkim_signatures; sig; sig = sig->next)
+  dkim_exim_verify_log_sig(sig);
+}
+
+
+void
+dkim_exim_verify_finish(void)
+{
+int rc;
+gstring * g = NULL;
+const uschar * errstr = NULL;
+
+store_pool = POOL_PERM;
+
+/* Delete eventual previous signature chain */
+
+dkim_signers = NULL;
+dkim_signatures = NULL;
+
+if (dkim_collect_error)
+  {
+  log_write(0, LOG_MAIN,
+      "DKIM: Error during validation, disabling signature verification: %.100s",
+      dkim_collect_error);
+  f.dkim_disable_verify = TRUE;
+  goto out;
+  }
+
+dkim_collect_input = 0;

 
 

-  /* Build a colon-separated list of signing domains (and identities, if present) in dkim_signers */
+/* Finish DKIM operation and fetch link to signatures chain */

 
 

-  if (sig->domain)
-    g = string_append_listele(g, ':', sig->domain);
+rc = pdkim_feed_finish(dkim_verify_ctx, (pdkim_signature **)&dkim_signatures,
+                       &errstr);
+if (rc != PDKIM_OK && errstr)
+  log_write(0, LOG_MAIN, "DKIM: validation error: %s", errstr);

 
 

-  if (sig->identity)
-    g = string_append_listele(g, ':', sig->identity);
+/* Build a colon-separated list of signing domains (and identities, if present) in dkim_signers */

 
 

-  /* Process next signature */
+for (pdkim_signature * sig = dkim_signatures; sig; sig = sig->next)
+  {
+  if (sig->domain)   g = string_append_listele(g, ':', sig->domain);
+  if (sig->identity) g = string_append_listele(g, ':', sig->identity);

   }
 
 if (g) dkim_signers = g->s;
   }
 
 if (g) dkim_signers = g->s;


@@ -277,40 +338,92 @@ store_pool = dkim_verify_oldpool;
 }
 
 
 }
 
 

-void
-dkim_exim_acl_setup(uschar * id)
+
+/* Args as per dkim_exim_acl_run() below */
+static int
+dkim_acl_call(uschar * id, gstring ** res_ptr,
+  uschar ** user_msgptr, uschar ** log_msgptr)
+{
+int rc;
+DEBUG(D_receive)
+  debug_printf("calling acl_smtp_dkim for dkim_cur_signer='%s'\n", id);
+
+rc = acl_check(ACL_WHERE_DKIM, NULL, acl_smtp_dkim, user_msgptr, log_msgptr);
+dkim_exim_verify_log_sig(dkim_cur_sig);
+*res_ptr = string_append_listele(*res_ptr, ':', dkim_verify_status);
+return rc;
+}
+
+
+
+/* For the given identity, run the DKIM ACL once for each matching signature.
+
+Arguments
+ id            Identity to look for in dkim signatures
+ res_ptr       ptr to growable string-list of status results,
+               appended to per ACL run
+ user_msgptr   where to put a user error (for SMTP response)
+ log_msgptr    where to put a logging message (not for SMTP response)
+
+Returns:       OK         access is granted by an ACCEPT verb
+               DISCARD    access is granted by a DISCARD verb
+               FAIL       access is denied
+               FAIL_DROP  access is denied; drop the connection
+               DEFER      can't tell at the moment
+               ERROR      disaster
+*/
+
+int
+dkim_exim_acl_run(uschar * id, gstring ** res_ptr,
+  uschar ** user_msgptr, uschar ** log_msgptr)

 {
 {

-pdkim_signature * sig;

 uschar * cmp_val;
 uschar * cmp_val;

+int rc = -1;

 
 

-dkim_cur_sig = NULL;
+dkim_verify_status = US"none";
+dkim_verify_reason = US"";

 dkim_cur_signer = id;
 
 dkim_cur_signer = id;
 

-if (dkim_disable_verify || !id || !dkim_verify_ctx)
-  return;
+if (f.dkim_disable_verify || !id || !dkim_verify_ctx)
+  return OK;

 
 

-/* Find signature to run ACL on */
+/* Find signatures to run ACL on */

 
 

-for (sig = dkim_signatures; sig; sig = sig->next)
+for (pdkim_signature * sig = dkim_signatures; sig; sig = sig->next)

   if (  (cmp_val = Ustrchr(id, '@') != NULL ? US sig->identity : US sig->domain)
      && strcmpic(cmp_val, id) == 0
      )
     {
   if (  (cmp_val = Ustrchr(id, '@') != NULL ? US sig->identity : US sig->domain)
      && strcmpic(cmp_val, id) == 0
      )
     {

-    dkim_cur_sig = sig;
-

     /* The "dkim_domain" and "dkim_selector" expansion variables have
     /* The "dkim_domain" and "dkim_selector" expansion variables have

-       related globals, since they are used in the signing code too.
-       Instead of inventing separate names for verification, we set
-       them here. This is easy since a domain and selector is guaranteed
-       to be in a signature. The other dkim_* expansion items are
-       dynamically fetched from dkim_cur_sig at expansion time (see
-       function below). */
+    related globals, since they are used in the signing code too.
+    Instead of inventing separate names for verification, we set
+    them here. This is easy since a domain and selector is guaranteed
+    to be in a signature. The other dkim_* expansion items are
+    dynamically fetched from dkim_cur_sig at expansion time (see
+    dkim_exim_expand_query() below). */

 
 

+    dkim_cur_sig = sig;

     dkim_signing_domain = US sig->domain;
     dkim_signing_selector = US sig->selector;
     dkim_key_length = sig->sighash.len * 8;
     dkim_signing_domain = US sig->domain;
     dkim_signing_selector = US sig->selector;
     dkim_key_length = sig->sighash.len * 8;

-    return;
+
+    /* These two return static strings, so we can compare the addr
+    later to see if the ACL overwrote them.  Check that when logging */
+
+    dkim_verify_status = dkim_exim_expand_query(DKIM_VERIFY_STATUS);
+    dkim_verify_reason = dkim_exim_expand_query(DKIM_VERIFY_REASON);
+
+    if ((rc = dkim_acl_call(id, res_ptr, user_msgptr, log_msgptr)) != OK)
+      return rc;

     }
     }

+
+if (rc != -1)
+  return rc;
+
+/* No matching sig found.  Call ACL once anyway. */
+
+dkim_cur_sig = NULL;
+return dkim_acl_call(id, res_ptr, user_msgptr, log_msgptr);

 }
 
 
 }
 
 


@@ -343,7 +456,7 @@ switch (what)
 uschar *
 dkim_exim_expand_query(int what)
 {
 uschar *
 dkim_exim_expand_query(int what)
 {

-if (!dkim_verify_ctx || dkim_disable_verify || !dkim_cur_sig)
+if (!dkim_verify_ctx || f.dkim_disable_verify || !dkim_cur_sig)

   return dkim_exim_expand_defaults(what);
 
 switch (what)
   return dkim_exim_expand_defaults(what);
 
 switch (what)


@@ -365,12 +478,12 @@ switch (what)
       }
 
   case DKIM_CANON_HEADERS:
       }
 
   case DKIM_CANON_HEADERS:

-  switch (dkim_cur_sig->canon_headers)
-    {
-    case PDKIM_CANON_RELAXED:  return US"relaxed";
-    case PDKIM_CANON_SIMPLE:
-    default:                   return US"simple";
-    }
+    switch (dkim_cur_sig->canon_headers)
+      {
+      case PDKIM_CANON_RELAXED:        return US"relaxed";
+      case PDKIM_CANON_SIMPLE:
+      default:                 return US"simple";
+      }

 
   case DKIM_COPIEDHEADERS:
     return dkim_cur_sig->copiedheaders
 
   case DKIM_COPIEDHEADERS:
     return dkim_cur_sig->copiedheaders


@@ -456,18 +569,33 @@ switch (what)
 }
 
 
 }
 
 

-/* Generate signatures for the given file, returning a string.
+void
+dkim_exim_sign_init(void)
+{
+int old_pool = store_pool;
+
+dkim_exim_init();
+store_pool = POOL_MAIN;
+pdkim_init_context(&dkim_sign_ctx, FALSE, &dkim_exim_query_dns_txt);
+store_pool = old_pool;
+}
+
+
+/* Generate signatures for the given file.

 If a prefix is given, prepend it to the file for the calculations.
 If a prefix is given, prepend it to the file for the calculations.

+
+Return:
+  NULL:                error; error string written
+  string:      signature header(s), or a zero-length string (not an error)

 */
 
 gstring *
 dkim_exim_sign(int fd, off_t off, uschar * prefix,
   struct ob_dkim * dkim, const uschar ** errstr)
 {
 */
 
 gstring *
 dkim_exim_sign(int fd, off_t off, uschar * prefix,
   struct ob_dkim * dkim, const uschar ** errstr)
 {

-const uschar * dkim_domain;
+const uschar * dkim_domain = NULL;

 int sep = 0;
 gstring * seen_doms = NULL;
 int sep = 0;
 gstring * seen_doms = NULL;

-pdkim_ctx ctx;

 pdkim_signature * sig;
 gstring * sigbuf;
 int pdkim_rc;
 pdkim_signature * sig;
 gstring * sigbuf;
 int pdkim_rc;


@@ -476,18 +604,21 @@ uschar buf[4096];
 int save_errno = 0;
 int old_pool = store_pool;
 uschar * errwhen;
 int save_errno = 0;
 int old_pool = store_pool;
 uschar * errwhen;

+const uschar * s;

 
 

-store_pool = POOL_MAIN;
+if (dkim->dot_stuffed)
+  dkim_sign_ctx.flags |= PDKIM_DOT_TERM;

 
 

-pdkim_init_context(&ctx, dkim->dot_stuffed, &dkim_exim_query_dns_txt);
+store_pool = POOL_MAIN;

 
 

-if (!(dkim_domain = expand_cstring(dkim->dkim_domain)))
+if ((s = dkim->dkim_domain) && !(dkim_domain = expand_cstring(s)))

   /* expansion error, do not send message. */
   { errwhen = US"dkim_domain"; goto expand_bad; }
 
 /* Set $dkim_domain expansion variable to each unique domain in list. */
 
   /* expansion error, do not send message. */
   { errwhen = US"dkim_domain"; goto expand_bad; }
 
 /* Set $dkim_domain expansion variable to each unique domain in list. */
 

-while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))
+if (dkim_domain)
+  while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))

   {
   const uschar * dkim_sel;
   int sel_sep = 0;
   {
   const uschar * dkim_sel;
   int sel_sep = 0;


@@ -498,6 +629,7 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))
   /* Only sign once for each domain, no matter how often it
   appears in the expanded list. */
 
   /* Only sign once for each domain, no matter how often it
   appears in the expanded list. */
 

+  dkim_signing_domain = string_copylc(dkim_signing_domain);

   if (match_isinlist(dkim_signing_domain, CUSS &seen_doms,
       0, NULL, NULL, MCL_STRING, TRUE, NULL) == OK)
     continue;
   if (match_isinlist(dkim_signing_domain, CUSS &seen_doms,
       0, NULL, NULL, MCL_STRING, TRUE, NULL) == OK)
     continue;


@@ -508,7 +640,6 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))
   for this domain. */
 
   if (!(dkim_sel = expand_string(dkim->dkim_selector)))
   for this domain. */
 
   if (!(dkim_sel = expand_string(dkim->dkim_selector)))

-  if (!(dkim_signing_selector = expand_string(dkim->dkim_selector)))

     { errwhen = US"dkim_selector"; goto expand_bad; }
 
   while ((dkim_signing_selector = string_nextinlist(&dkim_sel, &sel_sep,
     { errwhen = US"dkim_selector"; goto expand_bad; }
 
   while ((dkim_signing_selector = string_nextinlist(&dkim_sel, &sel_sep,


@@ -520,6 +651,8 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))
     uschar * dkim_private_key_expanded;
     uschar * dkim_hash_expanded;
     uschar * dkim_identity_expanded = NULL;
     uschar * dkim_private_key_expanded;
     uschar * dkim_hash_expanded;
     uschar * dkim_identity_expanded = NULL;

+    uschar * dkim_timestamps_expanded = NULL;
+    unsigned long tval = 0, xval = 0;

 
     /* Get canonicalization to use */
 
 
     /* Get canonicalization to use */
 


@@ -556,39 +689,10 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))
        )
       continue;                /* don't sign, but no error */
 
        )
       continue;                /* don't sign, but no error */
 

-    if (dkim_private_key_expanded[0] == '/')
-      {
-      int privkey_fd, off = 0, len;
-
-      /* Looks like a filename, load the private key. */
-
-      memset(big_buffer, 0, big_buffer_size);
-
-      if ((privkey_fd = open(CS dkim_private_key_expanded, O_RDONLY)) < 0)
-       {
-       log_write(0, LOG_MAIN | LOG_PANIC, "unable to open "
-                  "private key file for reading: %s",
-                  dkim_private_key_expanded);
-       goto bad;
-       }
-
-      do
-       {
-       if ((len = read(privkey_fd, big_buffer + off, big_buffer_size - 2 - off)) < 0)
-         {
-         (void) close(privkey_fd);
-         log_write(0, LOG_MAIN|LOG_PANIC, "unable to read private key file: %s",
-                    dkim_private_key_expanded);
-         goto bad;
-         }
-       off += len;
-       }
-      while (len > 0);
-
-      (void) close(privkey_fd);
-      big_buffer[off] = '\0';
-      dkim_private_key_expanded = big_buffer;
-      }
+    if (  dkim_private_key_expanded[0] == '/'
+       && !(dkim_private_key_expanded =
+            expand_file_big_buffer(dkim_private_key_expanded)))
+      goto bad;

 
     if (!(dkim_hash_expanded = expand_string(dkim->dkim_hash)))
       { errwhen = US"dkim_hash"; goto expand_bad; }
 
     if (!(dkim_hash_expanded = expand_string(dkim->dkim_hash)))
       { errwhen = US"dkim_hash"; goto expand_bad; }


@@ -599,10 +703,14 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))
       else if (!*dkim_identity_expanded)
        dkim_identity_expanded = NULL;
 
       else if (!*dkim_identity_expanded)
        dkim_identity_expanded = NULL;
 

-  /*XXX so we currently nail signing to RSA + this hash.
-  Need to extract algo from privkey and check for disallowed combos. */
+    if (dkim->dkim_timestamps)
+      if (!(dkim_timestamps_expanded = expand_string(dkim->dkim_timestamps)))
+       { errwhen = US"dkim_timestamps"; goto expand_bad; }
+      else
+       xval = (tval = (unsigned long) time(NULL))
+             + strtoul(CCS dkim_timestamps_expanded, NULL, 10);

 
 

-    if (!(sig = pdkim_init_sign(&ctx, dkim_signing_domain,
+    if (!(sig = pdkim_init_sign(&dkim_sign_ctx, dkim_signing_domain,

                          dkim_signing_selector,
                          dkim_private_key_expanded,
                          dkim_hash_expanded,
                          dkim_signing_selector,
                          dkim_private_key_expanded,
                          dkim_hash_expanded,


@@ -613,66 +721,160 @@ while ((dkim_signing_domain = string_nextinlist(&dkim_domain, &sep, NULL, 0)))
 
     pdkim_set_optional(sig,
                        CS dkim_sign_headers_expanded,
 
     pdkim_set_optional(sig,
                        CS dkim_sign_headers_expanded,

-                       dkim_identity_expanded,
+                       CS dkim_identity_expanded,

                        pdkim_canon,
                        pdkim_canon,

-                       pdkim_canon, -1, 0, 0);
+                       pdkim_canon, -1, tval, xval);

 
 

-    if (!ctx.sig)              /* link sig to context chain */
-      ctx.sig = sig;
+    if (!pdkim_set_sig_bodyhash(&dkim_sign_ctx, sig))
+      goto bad;
+
+    if (!dkim_sign_ctx.sig)            /* link sig to context chain */
+      dkim_sign_ctx.sig = sig;

     else
       {
     else
       {

-      pdkim_signature * n = ctx.sig;
+      pdkim_signature * n = dkim_sign_ctx.sig;

       while (n->next) n = n->next;
       n->next = sig;
       }
     }
   }
 
       while (n->next) n = n->next;
       n->next = sig;
       }
     }
   }
 

-if (prefix)
-  pdkim_feed(&ctx, prefix, Ustrlen(prefix));
-
-if (lseek(fd, off, SEEK_SET) < 0)
-  sread = -1;
-else
-  while ((sread = read(fd, &buf, sizeof(buf))) > 0)
-    if ((pdkim_rc = pdkim_feed(&ctx, buf, sread)) != PDKIM_OK)
-      goto pk_bad;
+/* We may need to carry on with the data-feed even if there are no DKIM sigs to
+produce, if some other package (eg. ARC) is signing. */

 
 

-/* Handle failed read above. */
-if (sread == -1)
+if (!dkim_sign_ctx.sig && !dkim->force_bodyhash)

   {
   {

-  debug_printf("DKIM: Error reading -K file.\n");
-  save_errno = errno;
-  goto bad;
+  DEBUG(D_transport) debug_printf("DKIM: no viable signatures to use\n");
+  sigbuf = string_get(1);      /* return a zero-len string */

   }
   }

+else
+  {
+  if (prefix && (pdkim_rc = pdkim_feed(&dkim_sign_ctx, prefix, Ustrlen(prefix))) != PDKIM_OK)
+    goto pk_bad;
+
+  if (lseek(fd, off, SEEK_SET) < 0)
+    sread = -1;
+  else
+    while ((sread = read(fd, &buf, sizeof(buf))) > 0)
+      if ((pdkim_rc = pdkim_feed(&dkim_sign_ctx, buf, sread)) != PDKIM_OK)
+       goto pk_bad;
+
+  /* Handle failed read above. */
+  if (sread == -1)
+    {
+    debug_printf("DKIM: Error reading -K file.\n");
+    save_errno = errno;
+    goto bad;
+    }

 
 

-/* Build string of headers, one per signature */
-
-if ((pdkim_rc = pdkim_feed_finish(&ctx, &sig, errstr)) != PDKIM_OK)
-  goto pk_bad;
+  /* Build string of headers, one per signature */

 
 

-for (sigbuf = NULL; sig; sig = sig->next)
-  sigbuf = string_append(sigbuf, 2, US sig->signature_header, US"\r\n");
+  if ((pdkim_rc = pdkim_feed_finish(&dkim_sign_ctx, &sig, errstr)) != PDKIM_OK)
+    goto pk_bad;

 
 

-(void) string_from_gstring(sigbuf);
+  if (!sig)
+    {
+    DEBUG(D_transport) debug_printf("DKIM: no signatures to use\n");
+    sigbuf = string_get(1);    /* return a zero-len string */
+    }
+  else for (sigbuf = NULL; sig; sig = sig->next)
+    sigbuf = string_append(sigbuf, 2, US sig->signature_header, US"\r\n");
+  }

 
 CLEANUP:
 
 CLEANUP:

+  (void) string_from_gstring(sigbuf);

   store_pool = old_pool;
   errno = save_errno;
   return sigbuf;
 
 pk_bad:
   log_write(0, LOG_MAIN|LOG_PANIC,
   store_pool = old_pool;
   errno = save_errno;
   return sigbuf;
 
 pk_bad:
   log_write(0, LOG_MAIN|LOG_PANIC,

-               "DKIM: signing failed: %.100s", pdkim_errstr(pdkim_rc));
+               "DKIM: signing failed: %.100s", pdkim_errstr(pdkim_rc));

 bad:
   sigbuf = NULL;
   goto CLEANUP;
 
 expand_bad:
 bad:
   sigbuf = NULL;
   goto CLEANUP;
 
 expand_bad:

-  log_write(0, LOG_MAIN | LOG_PANIC, "failed to expand %s: %s",
-             errwhen, expand_string_message);
+  *errstr = string_sprintf("failed to expand %s: %s",
+              errwhen, expand_string_message);
+  log_write(0, LOG_MAIN | LOG_PANIC, "%s", *errstr);

   goto bad;
 }
 
   goto bad;
 }
 

+
+
+
+gstring *
+authres_dkim(gstring * g)
+{
+int start = 0;         /* compiler quietening */
+
+DEBUG(D_acl) start = g->ptr;
+
+for (pdkim_signature * sig = dkim_signatures; sig; sig = sig->next)
+  {
+  g = string_catn(g, US";\n\tdkim=", 8);
+
+  if (sig->verify_status & PDKIM_VERIFY_POLICY)
+    g = string_append(g, 5,
+      US"policy (", dkim_verify_status, US" - ", dkim_verify_reason, US")");
+  else switch(sig->verify_status)
+    {
+    case PDKIM_VERIFY_NONE:    g = string_cat(g, US"none"); break;
+    case PDKIM_VERIFY_INVALID:
+      switch (sig->verify_ext_status)
+       {
+       case PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE:
+          g = string_cat(g, US"tmperror (pubkey unavailable)\n\t\t"); break;
+        case PDKIM_VERIFY_INVALID_BUFFER_SIZE:
+          g = string_cat(g, US"permerror (overlong public key record)\n\t\t"); break;
+        case PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD:
+        case PDKIM_VERIFY_INVALID_PUBKEY_IMPORT:
+          g = string_cat(g, US"neutral (public key record import problem)\n\t\t");
+          break;
+        case PDKIM_VERIFY_INVALID_SIGNATURE_ERROR:
+          g = string_cat(g, US"neutral (signature tag missing or invalid)\n\t\t");
+          break;
+        case PDKIM_VERIFY_INVALID_DKIM_VERSION:
+          g = string_cat(g, US"neutral (unsupported DKIM version)\n\t\t");
+          break;
+        default:
+          g = string_cat(g, US"permerror (unspecified problem)\n\t\t"); break;
+       }
+      break;
+    case PDKIM_VERIFY_FAIL:
+      switch (sig->verify_ext_status)
+       {
+       case PDKIM_VERIFY_FAIL_BODY:
+          g = string_cat(g,
+           US"fail (body hash mismatch; body probably modified in transit)\n\t\t");
+         break;
+        case PDKIM_VERIFY_FAIL_MESSAGE:
+          g = string_cat(g,
+           US"fail (signature did not verify; headers probably modified in transit)\n\t\t");
+         break;
+        default:
+          g = string_cat(g, US"fail (unspecified reason)\n\t\t");
+         break;
+       }
+      break;
+    case PDKIM_VERIFY_PASS:    g = string_cat(g, US"pass"); break;
+    default:                   g = string_cat(g, US"permerror"); break;
+    }
+  if (sig->domain)   g = string_append(g, 2, US" header.d=", sig->domain);
+  if (sig->identity) g = string_append(g, 2, US" header.i=", sig->identity);
+  if (sig->selector) g = string_append(g, 2, US" header.s=", sig->selector);
+  g = string_append(g, 2, US" header.a=", dkim_sig_to_a_tag(sig));
+  }
+
+DEBUG(D_acl)
+  if (g->ptr == start)
+    debug_printf("DKIM: no authres\n");
+  else
+    debug_printf("DKIM: authres '%.*s'\n", g->ptr - start - 3, g->s + start + 3);
+return g;
+}
+
+

 # endif        /*!MACRO_PREDEF*/
 #endif /*!DISABLE_DKIM*/
 # endif        /*!MACRO_PREDEF*/
 #endif /*!DISABLE_DKIM*/