OpenSSL: fix tls_eccurve setting explicit curve/group. Bug 2954

[exim.git] / src / src / dmarc.c

diff --git a/src/src/dmarc.c b/src/src/dmarc.c
index c4edc9159b72f5e0880d02950152a7c1268e271b..1187207502bcfff17029ce480c5175db01b42b4e 100644 (file)
--- a/src/src/dmarc.c
+++ b/src/src/dmarc.c
@@ -1,9 +1,11 @@
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/

-/* Experimental DMARC support.
+/* DMARC support.
+   Copyright (c) The Exim Maintainers 2019 - 2022

    Copyright (c) Todd Lyons <tlyons@exim.org> 2012 - 2014
    License: GPL */
    Copyright (c) Todd Lyons <tlyons@exim.org> 2012 - 2014
    License: GPL */

+/* SPDX-License-Identifier: GPL-2.0-or-later */

 
 /* Portions Copyright (c) 2012, 2013, The Trusted Domain Project;
    All rights reserved, licensed for use per LICENSE.opendmarc. */
 
 /* Portions Copyright (c) 2012, 2013, The Trusted Domain Project;
    All rights reserved, licensed for use per LICENSE.opendmarc. */


@@ -11,7 +13,7 @@
 /* Code for calling dmarc checks via libopendmarc. Called from acl.c. */
 
 #include "exim.h"
 /* Code for calling dmarc checks via libopendmarc. Called from acl.c. */
 
 #include "exim.h"

-#ifdef EXPERIMENTAL_DMARC
+#ifdef SUPPORT_DMARC

 # if !defined SUPPORT_SPF
 #  error SPF must also be enabled for DMARC
 # elif defined DISABLE_DKIM
 # if !defined SUPPORT_SPF
 #  error SPF must also be enabled for DMARC
 # elif defined DISABLE_DKIM


@@ -50,21 +52,32 @@ static dmarc_exim_p dmarc_policy_description[] = {
   { US"reject",     DMARC_RECORD_P_REJECT },
   { NULL,           0 }
 };
   { US"reject",     DMARC_RECORD_P_REJECT },
   { NULL,           0 }
 };

+
+
+gstring *
+dmarc_version_report(gstring * g)
+{
+return string_fmt_append(g, "Library version: dmarc: Compile: %d.%d.%d.%d\n",
+    (OPENDMARC_LIB_VERSION & 0xff000000) >> 24, (OPENDMARC_LIB_VERSION & 0x00ff0000) >> 16,
+    (OPENDMARC_LIB_VERSION & 0x0000ff00) >> 8, OPENDMARC_LIB_VERSION & 0x000000ff);
+}
+
+

 /* Accept an error_block struct, initialize if empty, parse to the
 /* Accept an error_block struct, initialize if empty, parse to the

- * end, and append the two strings passed to it.  Used for adding
- * variable amounts of value:pair data to the forensic emails. */
+end, and append the two strings passed to it.  Used for adding
+variable amounts of value:pair data to the forensic emails. */

 
 static error_block *
 add_to_eblock(error_block *eblock, uschar *t1, uschar *t2)
 {
 error_block *eb = store_malloc(sizeof(error_block));
 
 static error_block *
 add_to_eblock(error_block *eblock, uschar *t1, uschar *t2)
 {
 error_block *eb = store_malloc(sizeof(error_block));

-if (eblock == NULL)
+if (!eblock)

   eblock = eb;
 else
   {
   /* Find the end of the eblock struct and point it at eb */
   error_block *tmp = eblock;
   eblock = eb;
 else
   {
   /* Find the end of the eblock struct and point it at eb */
   error_block *tmp = eblock;

-  while(tmp->next != NULL)
+  while(tmp->next)

     tmp = tmp->next;
   tmp->next = eb;
   }
     tmp = tmp->next;
   tmp->next = eb;
   }


@@ -75,8 +88,8 @@ return eblock;
 }
 
 /* dmarc_init sets up a context that can be re-used for several
 }
 
 /* dmarc_init sets up a context that can be re-used for several

-   messages on the same SMTP connection (that come from the
-   same host with the same HELO string) */
+messages on the same SMTP connection (that come from the
+same host with the same HELO string) */

 
 int
 dmarc_init()
 
 int
 dmarc_init()


@@ -109,15 +122,15 @@ if (libdm_status != DMARC_PARSE_OKAY)
                       opendmarc_policy_status_to_str(libdm_status));
   dmarc_abort = TRUE;
   }
                       opendmarc_policy_status_to_str(libdm_status));
   dmarc_abort = TRUE;
   }

-if (!dmarc_tld_file)
+if (!dmarc_tld_file || !*dmarc_tld_file)

   {
   DEBUG(D_receive) debug_printf("DMARC: no dmarc_tld_file\n");
   dmarc_abort = TRUE;
   }
 else if (opendmarc_tld_read_file(CS dmarc_tld_file, NULL, NULL, NULL))
   {
   {
   DEBUG(D_receive) debug_printf("DMARC: no dmarc_tld_file\n");
   dmarc_abort = TRUE;
   }
 else if (opendmarc_tld_read_file(CS dmarc_tld_file, NULL, NULL, NULL))
   {

-  log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure to load tld list %s: %d",
-                      dmarc_tld_file, errno);
+  log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure to load tld list '%s': %s",
+                      dmarc_tld_file, strerror(errno));

   dmarc_abort = TRUE;
   }
 if (!sender_host_address)
   dmarc_abort = TRUE;
   }
 if (!sender_host_address)


@@ -203,6 +216,118 @@ if (  dmarc_policy == DMARC_POLICY_REJECT     && action == DMARC_RESULT_REJECT
     }
 }
 
     }
 }
 

+
+/* Look up a DNS dmarc record for the given domain.  Return it or NULL */
+
+static uschar *
+dmarc_dns_lookup(uschar * dom)
+{
+dns_answer * dnsa = store_get_dns_answer();
+dns_scan dnss;
+int rc = dns_lookup(dnsa, string_sprintf("_dmarc.%s", dom), T_TXT, NULL);
+
+if (rc == DNS_SUCCEED)
+  for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+       rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
+    if (rr->type == T_TXT && rr->size > 3)
+      {
+      uschar *record = string_copyn_taint(US rr->data, rr->size, GET_TAINTED);
+      store_free_dns_answer(dnsa);
+      return record;
+      }
+store_free_dns_answer(dnsa);
+return NULL;
+}
+
+
+static int
+dmarc_write_history_file()
+{
+int history_file_fd;
+ssize_t written_len;
+int tmp_ans;
+u_char **rua; /* aggregate report addressees */
+uschar *history_buffer = NULL;
+
+if (!dmarc_history_file)
+  {
+  DEBUG(D_receive) debug_printf("DMARC history file not set\n");
+  return DMARC_HIST_DISABLED;
+  }
+history_file_fd = log_open_as_exim(dmarc_history_file);
+
+if (history_file_fd < 0)
+  {
+  log_write(0, LOG_MAIN|LOG_PANIC, "failure to create DMARC history file: %s",
+                          dmarc_history_file);
+  return DMARC_HIST_FILE_ERR;
+  }
+
+/* Generate the contents of the history file */
+history_buffer = string_sprintf(
+  "job %s\nreporter %s\nreceived %ld\nipaddr %s\nfrom %s\nmfrom %s\n",
+  message_id, primary_hostname, time(NULL), sender_host_address,
+  header_from_sender, expand_string(US"$sender_address_domain"));
+
+if (spf_response)
+  history_buffer = string_sprintf("%sspf %d\n", history_buffer, dmarc_spf_ares_result);
+  /* history_buffer = string_sprintf("%sspf -1\n", history_buffer); */
+
+history_buffer = string_sprintf(
+  "%s%spdomain %s\npolicy %d\n",
+  history_buffer, dkim_history_buffer, dmarc_used_domain, dmarc_policy);
+
+if ((rua = opendmarc_policy_fetch_rua(dmarc_pctx, NULL, 0, 1)))
+  for (tmp_ans = 0; rua[tmp_ans]; tmp_ans++)
+    history_buffer = string_sprintf("%srua %s\n", history_buffer, rua[tmp_ans]);
+else
+  history_buffer = string_sprintf("%srua -\n", history_buffer);
+
+opendmarc_policy_fetch_pct(dmarc_pctx, &tmp_ans);
+history_buffer = string_sprintf("%spct %d\n", history_buffer, tmp_ans);
+
+opendmarc_policy_fetch_adkim(dmarc_pctx, &tmp_ans);
+history_buffer = string_sprintf("%sadkim %d\n", history_buffer, tmp_ans);
+
+opendmarc_policy_fetch_aspf(dmarc_pctx, &tmp_ans);
+history_buffer = string_sprintf("%saspf %d\n", history_buffer, tmp_ans);
+
+opendmarc_policy_fetch_p(dmarc_pctx, &tmp_ans);
+history_buffer = string_sprintf("%sp %d\n", history_buffer, tmp_ans);
+
+opendmarc_policy_fetch_sp(dmarc_pctx, &tmp_ans);
+history_buffer = string_sprintf("%ssp %d\n", history_buffer, tmp_ans);
+
+history_buffer = string_sprintf(
+  "%salign_dkim %d\nalign_spf %d\naction %d\n",
+  history_buffer, da, sa, action);
+
+/* Write the contents to the history file */
+DEBUG(D_receive)
+  debug_printf("DMARC logging history data for opendmarc reporting%s\n",
+            (host_checking || f.running_in_test_harness) ? " (not really)" : "");
+if (host_checking || f.running_in_test_harness)
+  {
+  DEBUG(D_receive)
+    debug_printf("DMARC history data for debugging:\n%s", history_buffer);
+  }
+else
+  {
+  written_len = write_to_fd_buf(history_file_fd,
+                               history_buffer,
+                               Ustrlen(history_buffer));
+  if (written_len == 0)
+    {
+    log_write(0, LOG_MAIN|LOG_PANIC, "failure to write to DMARC history file: %s",
+                          dmarc_history_file);
+    return DMARC_HIST_WRITE_ERR;
+    }
+  (void)close(history_file_fd);
+  }
+return DMARC_HIST_OK;
+}
+
+

 /* dmarc_process adds the envelope sender address to the existing
 context (if any), retrieves the result, sets up expansion
 strings and evaluates the condition outcome. */
 /* dmarc_process adds the envelope sender address to the existing
 context (if any), retrieves the result, sets up expansion
 strings and evaluates the condition outcome. */


@@ -214,6 +339,7 @@ int sr, origin;             /* used in SPF section */
 int dmarc_spf_result  = 0;  /* stores spf into dmarc conn ctx */
 int tmp_ans, c;
 pdkim_signature * sig = dkim_signatures;
 int dmarc_spf_result  = 0;  /* stores spf into dmarc conn ctx */
 int tmp_ans, c;
 pdkim_signature * sig = dkim_signatures;

+uschar * rr;

 BOOL has_dmarc_record = TRUE;
 u_char **ruf; /* forensic report addressees, if called for */
 
 BOOL has_dmarc_record = TRUE;
 u_char **ruf; /* forensic report addressees, if called for */
 


@@ -335,7 +461,12 @@ if (!dmarc_abort && !sender_host_authenticated)
                  vs == PDKIM_VERIFY_INVALID ? DMARC_POLICY_DKIM_OUTCOME_TMPFAIL :
                  DMARC_POLICY_DKIM_OUTCOME_NONE;
     libdm_status = opendmarc_policy_store_dkim(dmarc_pctx, US sig->domain,
                  vs == PDKIM_VERIFY_INVALID ? DMARC_POLICY_DKIM_OUTCOME_TMPFAIL :
                  DMARC_POLICY_DKIM_OUTCOME_NONE;
     libdm_status = opendmarc_policy_store_dkim(dmarc_pctx, US sig->domain,

-                                              dkim_result, US"");
+/* The opendmarc project broke its API in a way we can't detect * easily.
+ * The EDITME provides a DMARC_API variable */
+#if DMARC_API >= 100400
+                                               sig->selector,
+#endif
+                                               dkim_result, US"");

     DEBUG(D_receive)
       debug_printf("DMARC adding DKIM sender domain = %s\n", sig->domain);
     if (libdm_status != DMARC_PARSE_OKAY)
     DEBUG(D_receive)
       debug_printf("DMARC adding DKIM sender domain = %s\n", sig->domain);
     if (libdm_status != DMARC_PARSE_OKAY)


@@ -358,7 +489,15 @@ if (!dmarc_abort && !sender_host_authenticated)
                                         sig->domain, dkim_ares_result);
     sig = sig->next;
     }
                                         sig->domain, dkim_ares_result);
     sig = sig->next;
     }

-  libdm_status = opendmarc_policy_query_dmarc(dmarc_pctx, US"");
+
+  /* Look up DMARC policy record in DNS.  We do this explicitly, rather than
+  letting the dmarc library do it with opendmarc_policy_query_dmarc(), so that
+  our dns access path is used for debug tracing and for the testsuite
+  diversion. */
+
+  libdm_status = (rr = dmarc_dns_lookup(header_from_sender))
+    ? opendmarc_policy_store_dmarc(dmarc_pctx, rr, header_from_sender, NULL)
+    : DMARC_DNS_ERROR_NO_RECORD;

   switch (libdm_status)
     {
     case DMARC_DNS_ERROR_NXDOMAIN:
   switch (libdm_status)
     {
     case DMARC_DNS_ERROR_NXDOMAIN:


@@ -398,11 +537,11 @@ if (!dmarc_abort && !sender_host_authenticated)
   /* Can't use exim's string manipulation functions so allocate memory
   for libopendmarc using its max hostname length definition. */
 
   /* Can't use exim's string manipulation functions so allocate memory
   for libopendmarc using its max hostname length definition. */
 

-  dmarc_domain = US calloc(DMARC_MAXHOSTNAMELEN, sizeof(uschar));
+  dmarc_domain = store_get(DMARC_MAXHOSTNAMELEN, GET_TAINTED);

   libdm_status = opendmarc_policy_fetch_utilized_domain(dmarc_pctx,
     dmarc_domain, DMARC_MAXHOSTNAMELEN-1);
   libdm_status = opendmarc_policy_fetch_utilized_domain(dmarc_pctx,
     dmarc_domain, DMARC_MAXHOSTNAMELEN-1);

-  dmarc_used_domain = string_copy(dmarc_domain);
-  free(dmarc_domain);
+  store_release_above(dmarc_domain + Ustrlen(dmarc_domain)+1);
+  dmarc_used_domain = dmarc_domain;

 
   if (libdm_status != DMARC_PARSE_OKAY)
     log_write(0, LOG_MAIN|LOG_PANIC,
 
   if (libdm_status != DMARC_PARSE_OKAY)
     log_write(0, LOG_MAIN|LOG_PANIC,


@@ -485,94 +624,6 @@ if (!f.dmarc_disable_verify)
 return OK;
 }
 
 return OK;
 }
 

-static int
-dmarc_write_history_file()
-{
-int history_file_fd;
-ssize_t written_len;
-int tmp_ans;
-u_char **rua; /* aggregate report addressees */
-uschar *history_buffer = NULL;
-
-if (!dmarc_history_file)
-  {
-  DEBUG(D_receive) debug_printf("DMARC history file not set\n");
-  return DMARC_HIST_DISABLED;
-  }
-history_file_fd = log_create(dmarc_history_file);
-
-if (history_file_fd < 0)
-  {
-  log_write(0, LOG_MAIN|LOG_PANIC, "failure to create DMARC history file: %s",
-                          dmarc_history_file);
-  return DMARC_HIST_FILE_ERR;
-  }
-
-/* Generate the contents of the history file */
-history_buffer = string_sprintf(
-  "job %s\nreporter %s\nreceived %ld\nipaddr %s\nfrom %s\nmfrom %s\n",
-  message_id, primary_hostname, time(NULL), sender_host_address,
-  header_from_sender, expand_string(US"$sender_address_domain"));
-
-if (spf_response)
-  history_buffer = string_sprintf("%sspf %d\n", history_buffer, dmarc_spf_ares_result);
-  /* history_buffer = string_sprintf("%sspf -1\n", history_buffer); */
-
-history_buffer = string_sprintf(
-  "%s%spdomain %s\npolicy %d\n",
-  history_buffer, dkim_history_buffer, dmarc_used_domain, dmarc_policy);
-
-if ((rua = opendmarc_policy_fetch_rua(dmarc_pctx, NULL, 0, 1)))
-  for (tmp_ans = 0; rua[tmp_ans]; tmp_ans++)
-    history_buffer = string_sprintf("%srua %s\n", history_buffer, rua[tmp_ans]);
-else
-  history_buffer = string_sprintf("%srua -\n", history_buffer);
-
-opendmarc_policy_fetch_pct(dmarc_pctx, &tmp_ans);
-history_buffer = string_sprintf("%spct %d\n", history_buffer, tmp_ans);
-
-opendmarc_policy_fetch_adkim(dmarc_pctx, &tmp_ans);
-history_buffer = string_sprintf("%sadkim %d\n", history_buffer, tmp_ans);
-
-opendmarc_policy_fetch_aspf(dmarc_pctx, &tmp_ans);
-history_buffer = string_sprintf("%saspf %d\n", history_buffer, tmp_ans);
-
-opendmarc_policy_fetch_p(dmarc_pctx, &tmp_ans);
-history_buffer = string_sprintf("%sp %d\n", history_buffer, tmp_ans);
-
-opendmarc_policy_fetch_sp(dmarc_pctx, &tmp_ans);
-history_buffer = string_sprintf("%ssp %d\n", history_buffer, tmp_ans);
-
-history_buffer = string_sprintf(
-  "%salign_dkim %d\nalign_spf %d\naction %d\n",
-  history_buffer, da, sa, action);
-
-/* Write the contents to the history file */
-DEBUG(D_receive)
-  debug_printf("DMARC logging history data for opendmarc reporting%s\n",
-            (host_checking || f.running_in_test_harness) ? " (not really)" : "");
-if (host_checking || f.running_in_test_harness)
-  {
-  DEBUG(D_receive)
-    debug_printf("DMARC history data for debugging:\n%s", history_buffer);
-  }
-else
-  {
-  written_len = write_to_fd_buf(history_file_fd,
-                               history_buffer,
-                               Ustrlen(history_buffer));
-  if (written_len == 0)
-    {
-    log_write(0, LOG_MAIN|LOG_PANIC, "failure to write to DMARC history file: %s",
-                          dmarc_history_file);
-    return DMARC_HIST_WRITE_ERR;
-    }
-  (void)close(history_file_fd);
-  }
-return DMARC_HIST_OK;
-}
-
-

 uschar *
 dmarc_exim_expand_query(int what)
 {
 uschar *
 dmarc_exim_expand_query(int what)
 {


@@ -606,6 +657,6 @@ return g;
 }
 
 # endif /* SUPPORT_SPF */
 }
 
 # endif /* SUPPORT_SPF */

-#endif /* EXPERIMENTAL_DMARC */
+#endif /* SUPPORT_DMARC */

 /* vi: aw ai sw=2
  */
 /* vi: aw ai sw=2
  */