Lookups: fix pgsql multiple-row, single-column return

[users/heiko/exim.git] / src / src / expand.c

diff --git a/src/src/expand.c b/src/src/expand.c
index 47f1453bebc2cf89cf906e8d1d75c698f1cfeffd..e754fbc8cd3c8d25531153754cf8ed66032539bb 100644 (file)
--- a/src/src/expand.c
+++ b/src/src/expand.c
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 

-/* Copyright (c) University of Cambridge 1995 - 2015 */
+/* Copyright (c) University of Cambridge 1995 - 2017 */

 /* See the file NOTICE for conditions of use and distribution. */
 
 
 /* See the file NOTICE for conditions of use and distribution. */
 
 


@@ -17,22 +17,22 @@ static uschar *expand_string_internal(const uschar *, BOOL, const uschar **, BOO
 static int_eximarith_t expanded_string_integer(const uschar *, BOOL);
 
 #ifdef STAND_ALONE
 static int_eximarith_t expanded_string_integer(const uschar *, BOOL);
 
 #ifdef STAND_ALONE

-#ifndef SUPPORT_CRYPTEQ
-#define SUPPORT_CRYPTEQ
-#endif
+# ifndef SUPPORT_CRYPTEQ
+#  define SUPPORT_CRYPTEQ
+# endif

 #endif
 
 #ifdef LOOKUP_LDAP
 #endif
 
 #ifdef LOOKUP_LDAP

-#include "lookups/ldap.h"
+# include "lookups/ldap.h"

 #endif
 
 #ifdef SUPPORT_CRYPTEQ
 #endif
 
 #ifdef SUPPORT_CRYPTEQ

-#ifdef CRYPT_H
-#include <crypt.h>
-#endif
-#ifndef HAVE_CRYPT16
+# ifdef CRYPT_H
+#  include <crypt.h>
+# endif
+# ifndef HAVE_CRYPT16

 extern char* crypt16(char*, char*);
 extern char* crypt16(char*, char*);

-#endif
+# endif

 #endif
 
 /* The handling of crypt16() is a mess. I will record below the analysis of the
 #endif
 
 /* The handling of crypt16() is a mess. I will record below the analysis of the


@@ -46,7 +46,7 @@ the first 8 characters of the password using a 20-round version of crypt
 (standard crypt does 25 rounds).  It then crypts the next 8 characters,
 or an empty block if the password is less than 9 characters, using a
 20-round version of crypt and the same salt as was used for the first
 (standard crypt does 25 rounds).  It then crypts the next 8 characters,
 or an empty block if the password is less than 9 characters, using a
 20-round version of crypt and the same salt as was used for the first

-block.  Charaters after the first 16 are ignored.  It always generates
+block.  Characters after the first 16 are ignored.  It always generates

 a 16-byte hash, which is expressed together with the salt as a string
 of 24 base 64 digits.  Here are some links to peruse:
 
 a 16-byte hash, which is expressed together with the salt as a string
 of 24 base 64 digits.  Here are some links to peruse:
 


@@ -199,12 +199,15 @@ enum {
 static uschar *op_table_main[] = {
   US"address",
   US"addresses",
 static uschar *op_table_main[] = {
   US"address",
   US"addresses",

+  US"base32",
+  US"base32d",

   US"base62",
   US"base62d",
   US"base64",
   US"base64d",
   US"domain",
   US"escape",
   US"base62",
   US"base62d",
   US"base64",
   US"base64d",
   US"domain",
   US"escape",

+  US"escape8bit",

   US"eval",
   US"eval10",
   US"expand",
   US"eval",
   US"eval10",
   US"expand",


@@ -231,6 +234,7 @@ static uschar *op_table_main[] = {
   US"s",
   US"sha1",
   US"sha256",
   US"s",
   US"sha1",
   US"sha256",

+  US"sha3",

   US"stat",
   US"str2b64",
   US"strlen",
   US"stat",
   US"str2b64",
   US"strlen",


@@ -241,12 +245,15 @@ static uschar *op_table_main[] = {
 enum {
   EOP_ADDRESS =  nelem(op_table_underscore),
   EOP_ADDRESSES,
 enum {
   EOP_ADDRESS =  nelem(op_table_underscore),
   EOP_ADDRESSES,

+  EOP_BASE32,
+  EOP_BASE32D,

   EOP_BASE62,
   EOP_BASE62D,
   EOP_BASE64,
   EOP_BASE64D,
   EOP_DOMAIN,
   EOP_ESCAPE,
   EOP_BASE62,
   EOP_BASE62D,
   EOP_BASE64,
   EOP_BASE64D,
   EOP_DOMAIN,
   EOP_ESCAPE,

+  EOP_ESCAPE8BIT,

   EOP_EVAL,
   EOP_EVAL10,
   EOP_EXPAND,
   EOP_EVAL,
   EOP_EVAL10,
   EOP_EXPAND,


@@ -273,6 +280,7 @@ enum {
   EOP_S,
   EOP_SHA1,
   EOP_SHA256,
   EOP_S,
   EOP_SHA1,
   EOP_SHA256,

+  EOP_SHA3,

   EOP_STAT,
   EOP_STR2B64,
   EOP_STRLEN,
   EOP_STAT,
   EOP_STR2B64,
   EOP_STRLEN,


@@ -480,10 +488,6 @@ static var_entry var_table[] = {
   { "dcc_header",          vtype_stringptr,   &dcc_header },
   { "dcc_result",          vtype_stringptr,   &dcc_result },
 #endif
   { "dcc_header",          vtype_stringptr,   &dcc_header },
   { "dcc_result",          vtype_stringptr,   &dcc_result },
 #endif

-#ifdef WITH_OLD_DEMIME
-  { "demime_errorlevel",   vtype_int,         &demime_errorlevel },
-  { "demime_reason",       vtype_stringptr,   &demime_reason },
-#endif

 #ifndef DISABLE_DKIM
   { "dkim_algo",           vtype_dkim,        (void *)DKIM_ALGO },
   { "dkim_bodylength",     vtype_dkim,        (void *)DKIM_BODYLENGTH },
 #ifndef DISABLE_DKIM
   { "dkim_algo",           vtype_dkim,        (void *)DKIM_ALGO },
   { "dkim_bodylength",     vtype_dkim,        (void *)DKIM_BODYLENGTH },


@@ -504,8 +508,8 @@ static var_entry var_table[] = {
   { "dkim_key_testing",    vtype_dkim,        (void *)DKIM_KEY_TESTING },
   { "dkim_selector",       vtype_stringptr,   &dkim_signing_selector },
   { "dkim_signers",        vtype_stringptr,   &dkim_signers },
   { "dkim_key_testing",    vtype_dkim,        (void *)DKIM_KEY_TESTING },
   { "dkim_selector",       vtype_stringptr,   &dkim_signing_selector },
   { "dkim_signers",        vtype_stringptr,   &dkim_signers },

-  { "dkim_verify_reason",  vtype_dkim,        (void *)DKIM_VERIFY_REASON },
-  { "dkim_verify_status",  vtype_dkim,        (void *)DKIM_VERIFY_STATUS},
+  { "dkim_verify_reason",  vtype_stringptr,   &dkim_verify_reason },
+  { "dkim_verify_status",  vtype_stringptr,   &dkim_verify_status },

 #endif
 #ifdef EXPERIMENTAL_DMARC
   { "dmarc_ar_header",     vtype_stringptr,   &dmarc_ar_header },
 #endif
 #ifdef EXPERIMENTAL_DMARC
   { "dmarc_ar_header",     vtype_stringptr,   &dmarc_ar_header },


@@ -532,9 +536,6 @@ static var_entry var_table[] = {
   { "exim_path",           vtype_stringptr,   &exim_path },
   { "exim_uid",            vtype_uid,         &exim_uid },
   { "exim_version",        vtype_stringptr,   &version_string },
   { "exim_path",           vtype_stringptr,   &exim_path },
   { "exim_uid",            vtype_uid,         &exim_uid },
   { "exim_version",        vtype_stringptr,   &version_string },

-#ifdef WITH_OLD_DEMIME
-  { "found_extension",     vtype_stringptr,   &found_extension },
-#endif

   { "headers_added",       vtype_string_func, &fn_hdrs_added },
   { "home",                vtype_stringptr,   &deliver_home },
   { "host",                vtype_stringptr,   &deliver_host },
   { "headers_added",       vtype_string_func, &fn_hdrs_added },
   { "home",                vtype_stringptr,   &deliver_home },
   { "host",                vtype_stringptr,   &deliver_host },


@@ -632,6 +633,7 @@ static var_entry var_table[] = {
   { "prvscheck_result",    vtype_stringptr,   &prvscheck_result },
   { "qualify_domain",      vtype_stringptr,   &qualify_domain_sender },
   { "qualify_recipient",   vtype_stringptr,   &qualify_domain_recipient },
   { "prvscheck_result",    vtype_stringptr,   &prvscheck_result },
   { "qualify_domain",      vtype_stringptr,   &qualify_domain_sender },
   { "qualify_recipient",   vtype_stringptr,   &qualify_domain_recipient },

+  { "queue_name",          vtype_stringptr,   &queue_name },

   { "rcpt_count",          vtype_int,         &rcpt_count },
   { "rcpt_defer_count",    vtype_int,         &rcpt_defer_count },
   { "rcpt_fail_count",     vtype_int,         &rcpt_fail_count },
   { "rcpt_count",          vtype_int,         &rcpt_count },
   { "rcpt_defer_count",    vtype_int,         &rcpt_defer_count },
   { "rcpt_fail_count",     vtype_int,         &rcpt_fail_count },


@@ -640,7 +642,7 @@ static var_entry var_table[] = {
   { "received_ip_address", vtype_stringptr,   &interface_address },
   { "received_port",       vtype_int,         &interface_port },
   { "received_protocol",   vtype_stringptr,   &received_protocol },
   { "received_ip_address", vtype_stringptr,   &interface_address },
   { "received_port",       vtype_int,         &interface_port },
   { "received_protocol",   vtype_stringptr,   &received_protocol },

-  { "received_time",       vtype_int,         &received_time },
+  { "received_time",       vtype_int,         &received_time.tv_sec },

   { "recipient_data",      vtype_stringptr,   &recipient_data },
   { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
   { "recipients",          vtype_string_func, &fn_recipients },
   { "recipient_data",      vtype_stringptr,   &recipient_data },
   { "recipient_verify_failure",vtype_stringptr,&recipient_verify_failure },
   { "recipients",          vtype_string_func, &fn_recipients },


@@ -678,6 +680,7 @@ static var_entry var_table[] = {
   { "smtp_active_hostname", vtype_stringptr,  &smtp_active_hostname },
   { "smtp_command",        vtype_stringptr,   &smtp_cmd_buffer },
   { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },
   { "smtp_active_hostname", vtype_stringptr,  &smtp_active_hostname },
   { "smtp_command",        vtype_stringptr,   &smtp_cmd_buffer },
   { "smtp_command_argument", vtype_stringptr, &smtp_cmd_argument },

+  { "smtp_command_history", vtype_string_func, &smtp_cmd_hist },

   { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
   { "smtp_notquit_reason", vtype_stringptr,   &smtp_notquit_reason },
   { "sn0",                 vtype_filter_int,  &filter_sn[0] },
   { "smtp_count_at_connection_start", vtype_int, &smtp_accept_count },
   { "smtp_notquit_reason", vtype_stringptr,   &smtp_notquit_reason },
   { "sn0",                 vtype_filter_int,  &filter_sn[0] },


@@ -842,6 +845,9 @@ static int utf8_table2[] = { 0xff, 0x1f, 0x0f, 0x07, 0x03, 0x01};
     }
 
 
     }
 
 

+
+static uschar * base32_chars = US"abcdefghijklmnopqrstuvwxyz234567";
+

 /*************************************************
 *           Binary chop search on a table        *
 *************************************************/
 /*************************************************
 *           Binary chop search on a table        *
 *************************************************/


@@ -1478,16 +1484,14 @@ while (*s != 0)
 /* If value2 is unset, just compute one number */
 
 if (value2 < 0)
 /* If value2 is unset, just compute one number */
 
 if (value2 < 0)

-  {
-  s = string_sprintf("%d", total % value1);
-  }
+  s = string_sprintf("%lu", total % value1);

 
 /* Otherwise do a div/mod hash */
 
 else
   {
   total = total % (value1 * value2);
 
 /* Otherwise do a div/mod hash */
 
 else
   {
   total = total % (value1 * value2);

-  s = string_sprintf("%d/%d", total/value2, total % value2);
+  s = string_sprintf("%lu/%lu", total/value2, total % value2);

   }
 
 *len = Ustrlen(s);
   }
 
 *len = Ustrlen(s);


@@ -1549,11 +1553,9 @@ for (i = 0; i < 2; i++)
   int size = 0;
   header_line *h;
 
   int size = 0;
   header_line *h;
 

-  for (h = header_list; size < header_insert_maxlen && h != NULL; h = h->next)
-    {
-    if (h->type != htype_old && h->text != NULL)  /* NULL => Received: placeholder */
-      {
-      if (name == NULL || (len <= h->slen && strncmpic(name, h->text, len) == 0))
+  for (h = header_list; size < header_insert_maxlen && h; h = h->next)
+    if (h->type != htype_old && h->text)  /* NULL => Received: placeholder */
+      if (!name || (len <= h->slen && strncmpic(name, h->text, len) == 0))

         {
         int ilen;
         uschar *t;
         {
         int ilen;
         uschar *t;


@@ -1575,7 +1577,7 @@ for (i = 0; i < 2; i++)
         that contains an address list, except when asked for raw headers. Only
         need to do this once. */
 
         that contains an address list, except when asked for raw headers. Only
         need to do this once. */
 

-        if (!want_raw && name != NULL && comma == 0 &&
+        if (!want_raw && name && comma == 0 &&

             Ustrchr("BCFRST", h->type) != NULL)
           comma = 1;
 
             Ustrchr("BCFRST", h->type) != NULL)
           comma = 1;
 


@@ -1584,7 +1586,7 @@ for (i = 0; i < 2; i++)
 
         size += ilen + comma + 1;  /* +1 for the newline */
 
 
         size += ilen + comma + 1;  /* +1 for the newline */
 

-        /* Second pass - concatentate the data, up to a maximum. Note that
+        /* Second pass - concatenate the data, up to a maximum. Note that

         the loop stops when size hits the limit. */
 
         if (i != 0)
         the loop stops when size hits the limit. */
 
         if (i != 0)


@@ -1608,8 +1610,6 @@ for (i = 0; i < 2; i++)
             }
           }
         }
             }
           }
         }

-      }
-    }

 
   /* At end of first pass, return NULL if no header found. Then truncate size
   if necessary, and get the buffer to hold the data, returning the buffer size.
 
   /* At end of first pass, return NULL if no header found. Then truncate size
   if necessary, and get the buffer to hold the data, returning the buffer size.


@@ -1627,9 +1627,7 @@ for (i = 0; i < 2; i++)
 /* That's all we do for raw header expansion. */
 
 if (want_raw)
 /* That's all we do for raw header expansion. */
 
 if (want_raw)

-  {

   *ptr = 0;
   *ptr = 0;

-  }

 
 /* Otherwise, remove a final newline and a redundant added comma. Then we do
 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()
 
 /* Otherwise, remove a final newline and a redundant added comma. Then we do
 RFC 2047 decoding, translating the charset if requested. The rfc2047_decode2()


@@ -1668,21 +1666,18 @@ generated from a system filter, but not elsewhere. */
 static uschar *
 fn_recipients(void)
 {
 static uschar *
 fn_recipients(void)
 {

-if (!enable_dollar_recipients) return NULL; else
+gstring * g = NULL;
+int i;
+
+if (!enable_dollar_recipients) return NULL;
+
+for (i = 0; i < recipients_count; i++)

   {
   {

-  int size = 128;
-  int ptr = 0;
-  int i;
-  uschar * s = store_get(size);
-  for (i = 0; i < recipients_count; i++)
-    {
-    if (i != 0) s = string_cat(s, &size, &ptr, US", ", 2);
-    s = string_cat(s, &size, &ptr, recipients_list[i].address,
-      Ustrlen(recipients_list[i].address));
-    }
-  s[ptr] = 0;     /* string_cat() leaves room */
-  return s;
+  /*XXX variant of list_appendele? */
+  if (i != 0) g = string_catn(g, US", ", 2);
+  g = string_cat(g, recipients_list[i].address);

   }
   }

+return string_from_gstring(g);

 }
 
 
 }
 
 


@@ -1834,7 +1829,7 @@ switch (vp->type)
   case vtype_msgbody:                        /* Pointer to msgbody string */
   case vtype_msgbody_end:                    /* Ditto, the end of the msg */
     ss = (uschar **)(val);
   case vtype_msgbody:                        /* Pointer to msgbody string */
   case vtype_msgbody_end:                    /* Ditto, the end of the msg */
     ss = (uschar **)(val);

-    if (*ss == NULL && deliver_datafile >= 0)  /* Read body when needed */
+    if (!*ss && deliver_datafile >= 0)  /* Read body when needed */

       {
       uschar *body;
       off_t start_offset = SPOOL_DATA_START_OFFSET;
       {
       uschar *body;
       off_t start_offset = SPOOL_DATA_START_OFFSET;


@@ -1867,7 +1862,7 @@ switch (vp->type)
            { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
        }
       }
            { if (body[--len] == '\n' || body[len] == 0) body[len] = ' '; }
        }
       }

-    return (*ss == NULL)? US"" : *ss;
+    return *ss ? *ss : US"";

 
   case vtype_todbsdin:                       /* BSD inbox time of day */
     return tod_stamp(tod_bsdin);
 
   case vtype_todbsdin:                       /* BSD inbox time of day */
     return tod_stamp(tod_bsdin);


@@ -1962,6 +1957,7 @@ return;          /* Unknown variable name, fail silently */
 
 
 
 
 
 

+

 /*************************************************
 *           Read and expand substrings           *
 *************************************************/
 /*************************************************
 *           Read and expand substrings           *
 *************************************************/


@@ -1999,12 +1995,17 @@ for (i = 0; i < n; i++)
   {
   if (*s != '{')
     {
   {
   if (*s != '{')
     {

-    if (i < m) return 1;
+    if (i < m)
+      {
+      expand_string_message = string_sprintf("Not enough arguments for '%s' "
+       "(min is %d)", name, m);
+      return 1;
+      }

     sub[i] = NULL;
     break;
     }
     sub[i] = NULL;
     break;
     }

-  sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, resetok);
-  if (sub[i] == NULL) return 3;
+  if (!(sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, resetok)))
+    return 3;

   if (*s++ != '}') return 1;
   while (isspace(*s)) s++;
   }
   if (*s++ != '}') return 1;
   while (isspace(*s)) s++;
   }


@@ -2012,10 +2013,11 @@ if (check_end && *s++ != '}')
   {
   if (s[-1] == '{')
     {
   {
   if (s[-1] == '{')
     {

-    expand_string_message = string_sprintf("Too many arguments for \"%s\" "
+    expand_string_message = string_sprintf("Too many arguments for '%s' "

       "(max is %d)", name, n);
     return 2;
     }
       "(max is %d)", name, n);
     return 2;
     }

+  expand_string_message = string_sprintf("missing '}' after '%s'", name);

   return 1;
   }
 
   return 1;
   }
 


@@ -2058,7 +2060,7 @@ Load args from sub array to globals, and call acl_check().
 Sub array will be corrupted on return.
 
 Returns:       OK         access is granted by an ACCEPT verb
 Sub array will be corrupted on return.
 
 Returns:       OK         access is granted by an ACCEPT verb

-               DISCARD    access is granted by a DISCARD verb
+               DISCARD    access is (apparently) granted by a DISCARD verb

               FAIL       access is denied
               FAIL_DROP  access is denied; drop the connection
               DEFER      can't tell at the moment
               FAIL       access is denied
               FAIL_DROP  access is denied; drop the connection
               DEFER      can't tell at the moment


@@ -2088,7 +2090,7 @@ while (i < nsub)
   }
 
 DEBUG(D_expand)
   }
 
 DEBUG(D_expand)

-  debug_printf("expanding: acl: %s  arg: %s%s\n",
+  debug_printf_indent("expanding: acl: %s  arg: %s%s\n",

     sub[0],
     acl_narg>0 ? acl_arg[0] : US"<none>",
     acl_narg>1 ? " +more"   : "");
     sub[0],
     acl_narg>0 ? acl_arg[0] : US"<none>",
     acl_narg>1 ? " +more"   : "");


@@ -2358,8 +2360,6 @@ switch(cond_type)
     uschar *sub[10];
     uschar *user_msg;
     BOOL cond = FALSE;
     uschar *sub[10];
     uschar *user_msg;
     BOOL cond = FALSE;

-    int size = 0;
-    int ptr = 0;

 
     while (isspace(*s)) s++;
     if (*s++ != '{') goto COND_FAILED_CURLY_START;     /*}*/
 
     while (isspace(*s)) s++;
     if (*s++ != '{') goto COND_FAILED_CURLY_START;     /*}*/


@@ -2373,27 +2373,28 @@ switch(cond_type)
       case 3: return NULL;
       }
 
       case 3: return NULL;
       }
 

-    *resetok = FALSE;
-    if (yield != NULL) switch(eval_acl(sub, nelem(sub), &user_msg))
+    if (yield != NULL)
+      {
+      *resetok = FALSE;        /* eval_acl() might allocate; do not reclaim */
+      switch(eval_acl(sub, nelem(sub), &user_msg))

        {
        case OK:
          cond = TRUE;
        case FAIL:
           lookup_value = NULL;
          if (user_msg)
        {
        case OK:
          cond = TRUE;
        case FAIL:
           lookup_value = NULL;
          if (user_msg)

-           {
-            lookup_value = string_cat(NULL, &size, &ptr, user_msg, Ustrlen(user_msg));
-            lookup_value[ptr] = '\0';
-           }
+            lookup_value = string_copy(user_msg);

          *yield = cond == testfor;
          break;
 
        case DEFER:
           expand_string_forcedfail = TRUE;
          *yield = cond == testfor;
          break;
 
        case DEFER:
           expand_string_forcedfail = TRUE;

+         /*FALLTHROUGH*/

        default:
           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
          return NULL;
        }
        default:
           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
          return NULL;
        }

+      }

     return s;
     }
 
     return s;
     }
 


@@ -2507,19 +2508,17 @@ switch(cond_type)
     checking for them individually. */
 
     if (!isalpha(name[0]) && yield != NULL)
     checking for them individually. */
 
     if (!isalpha(name[0]) && yield != NULL)

-      {

       if (sub[i][0] == 0)
         {
         num[i] = 0;
         DEBUG(D_expand)
       if (sub[i][0] == 0)
         {
         num[i] = 0;
         DEBUG(D_expand)

-          debug_printf("empty string cast to zero for numerical comparison\n");
+          debug_printf_indent("empty string cast to zero for numerical comparison\n");

         }
       else
         {
         num[i] = expanded_string_integer(sub[i], FALSE);
         if (expand_string_message != NULL) return NULL;
         }
         }
       else
         {
         num[i] = expanded_string_integer(sub[i], FALSE);
         if (expand_string_message != NULL) return NULL;
         }

-      }

     }
 
   /* Result not required */
     }
 
   /* Result not required */


@@ -2687,7 +2686,7 @@ switch(cond_type)
       uschar digest[16];
 
       md5_start(&base);
       uschar digest[16];
 
       md5_start(&base);

-      md5_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
+      md5_end(&base, sub[0], Ustrlen(sub[0]), digest);

 
       /* If the length that we are comparing against is 24, the MD5 digest
       is expressed as a base64 string. This is the way LDAP does it. However,
 
       /* If the length that we are comparing against is 24, the MD5 digest
       is expressed as a base64 string. This is the way LDAP does it. However,


@@ -2696,7 +2695,7 @@ switch(cond_type)
 
       if (sublen == 24)
         {
 
       if (sublen == 24)
         {

-        uschar *coded = b64encode((uschar *)digest, 16);
+        uschar *coded = b64encode(digest, 16);

         DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
         tempcond = (Ustrcmp(coded, sub[1]+5) == 0);
         DEBUG(D_auth) debug_printf("crypteq: using MD5+B64 hashing\n"
           "  subject=%s\n  crypted=%s\n", coded, sub[1]+5);
         tempcond = (Ustrcmp(coded, sub[1]+5) == 0);


@@ -2722,11 +2721,11 @@ switch(cond_type)
     else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
       {
       int sublen = Ustrlen(sub[1]+6);
     else if (strncmpic(sub[1], US"{sha1}", 6) == 0)
       {
       int sublen = Ustrlen(sub[1]+6);

-      sha1 base;
+      hctx h;

       uschar digest[20];
 
       uschar digest[20];
 

-      sha1_start(&base);
-      sha1_end(&base, (uschar *)sub[0], Ustrlen(sub[0]), digest);
+      sha1_start(&h);
+      sha1_end(&h, sub[0], Ustrlen(sub[0]), digest);

 
       /* If the length that we are comparing against is 28, assume the SHA1
       digest is expressed as a base64 string. If the length is 40, assume a
 
       /* If the length that we are comparing against is 28, assume the SHA1
       digest is expressed as a base64 string. If the length is 40, assume a


@@ -2734,7 +2733,7 @@ switch(cond_type)
 
       if (sublen == 28)
         {
 
       if (sublen == 28)
         {

-        uschar *coded = b64encode((uschar *)digest, 20);
+        uschar *coded = b64encode(digest, 20);

         DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
         tempcond = (Ustrcmp(coded, sub[1]+6) == 0);
         DEBUG(D_auth) debug_printf("crypteq: using SHA1+B64 hashing\n"
           "  subject=%s\n  crypted=%s\n", coded, sub[1]+6);
         tempcond = (Ustrcmp(coded, sub[1]+6) == 0);


@@ -2822,18 +2821,21 @@ switch(cond_type)
       uschar *save_iterate_item = iterate_item;
       int (*compare)(const uschar *, const uschar *);
 
       uschar *save_iterate_item = iterate_item;
       int (*compare)(const uschar *, const uschar *);
 

-      DEBUG(D_expand) debug_printf("condition: %s\n", name);
+      DEBUG(D_expand) debug_printf_indent("condition: %s  item: %s\n", name, sub[0]);

 
       tempcond = FALSE;
       compare = cond_type == ECOND_INLISTI
         ? strcmpic : (int (*)(const uschar *, const uschar *)) strcmp;
 
       while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))
 
       tempcond = FALSE;
       compare = cond_type == ECOND_INLISTI
         ? strcmpic : (int (*)(const uschar *, const uschar *)) strcmp;
 
       while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))

+       {
+       DEBUG(D_expand) debug_printf_indent(" compare %s\n", iterate_item);

         if (compare(sub[0], iterate_item) == 0)
           {
           tempcond = TRUE;
           break;
           }
         if (compare(sub[0], iterate_item) == 0)
           {
           tempcond = TRUE;
           break;
           }

+       }

       iterate_item = save_iterate_item;
       }
 
       iterate_item = save_iterate_item;
       }
 


@@ -2910,7 +2912,7 @@ switch(cond_type)
     int sep = 0;
     uschar *save_iterate_item = iterate_item;
 
     int sep = 0;
     uschar *save_iterate_item = iterate_item;
 

-    DEBUG(D_expand) debug_printf("condition: %s\n", name);
+    DEBUG(D_expand) debug_printf_indent("condition: %s\n", name);

 
     while (isspace(*s)) s++;
     if (*s++ != '{') goto COND_FAILED_CURLY_START;     /* }-for-text-editors */
 
     while (isspace(*s)) s++;
     if (*s++ != '{') goto COND_FAILED_CURLY_START;     /* }-for-text-editors */


@@ -2949,7 +2951,7 @@ switch(cond_type)
     list = sub[0];
     while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
       {
     list = sub[0];
     while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
       {

-      DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
+      DEBUG(D_expand) debug_printf_indent("%s: $item = \"%s\"\n", name, iterate_item);

       if (!eval_condition(sub[1], resetok, &tempcond))
         {
         expand_string_message = string_sprintf("%s inside \"%s\" condition",
       if (!eval_condition(sub[1], resetok, &tempcond))
         {
         expand_string_message = string_sprintf("%s inside \"%s\" condition",


@@ -2957,7 +2959,7 @@ switch(cond_type)
         iterate_item = save_iterate_item;
         return NULL;
         }
         iterate_item = save_iterate_item;
         return NULL;
         }

-      DEBUG(D_expand) debug_printf("%s: condition evaluated to %s\n", name,
+      DEBUG(D_expand) debug_printf_indent("%s: condition evaluated to %s\n", name,

         tempcond? "true":"false");
 
       if (yield != NULL) *yield = (tempcond == testfor);
         tempcond? "true":"false");
 
       if (yield != NULL) *yield = (tempcond == testfor);


@@ -3014,7 +3016,7 @@ switch(cond_type)
         }
       }
     DEBUG(D_expand)
         }
       }
     DEBUG(D_expand)

-      debug_printf("considering %s: %s\n", ourname, len ? t : US"<empty>");
+      debug_printf_indent("considering %s: %s\n", ourname, len ? t : US"<empty>");

     /* logic for the lax case from expand_check_condition(), which also does
     expands, and the logic is both short and stable enough that there should
     be no maintenance burden from replicating it. */
     /* logic for the lax case from expand_check_condition(), which also does
     expands, and the logic is both short and stable enough that there should
     be no maintenance burden from replicating it. */


@@ -3041,6 +3043,8 @@ switch(cond_type)
        "value \"%s\"", t);
       return NULL;
       }
        "value \"%s\"", t);
       return NULL;
       }

+    DEBUG(D_expand) debug_printf_indent("%s: condition evaluated to %s\n", ourname,
+        boolvalue? "true":"false");

     if (yield != NULL) *yield = (boolvalue == testfor);
     return s;
     }
     if (yield != NULL) *yield = (boolvalue == testfor);
     return s;
     }


@@ -3152,9 +3156,7 @@ Arguments:
   yes            TRUE if the first string is to be used, else use the second
   save_lookup    a value to put back into lookup_value before the 2nd expansion
   sptr           points to the input string pointer
   yes            TRUE if the first string is to be used, else use the second
   save_lookup    a value to put back into lookup_value before the 2nd expansion
   sptr           points to the input string pointer

-  yieldptr       points to the output string pointer
-  sizeptr        points to the output string size
-  ptrptr         points to the output string pointer
+  yieldptr       points to the output growable-string pointer

   type           "lookup", "if", "extract", "run", "env", "listextract" or
                  "certextract" for error message
   resetok       if not NULL, pointer to flag - write FALSE if unsafe to reset
   type           "lookup", "if", "extract", "run", "env", "listextract" or
                  "certextract" for error message
   resetok       if not NULL, pointer to flag - write FALSE if unsafe to reset


@@ -3167,11 +3169,12 @@ Returns:         0 OK; lookup_value has been reset to save_lookup
 
 static int
 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, const uschar **sptr,
 
 static int
 process_yesno(BOOL skipping, BOOL yes, uschar *save_lookup, const uschar **sptr,

-  uschar **yieldptr, int *sizeptr, int *ptrptr, uschar *type, BOOL *resetok)
+  gstring ** yieldptr, uschar *type, BOOL *resetok)

 {
 int rc = 0;
 const uschar *s = *sptr;    /* Local value */
 uschar *sub1, *sub2;
 {
 int rc = 0;
 const uschar *s = *sptr;    /* Local value */
 uschar *sub1, *sub2;

+const uschar * errwhere;

 
 /* If there are no following strings, we substitute the contents of $value for
 lookups and for extractions in the success case. For the ${if item, the string
 
 /* If there are no following strings, we substitute the contents of $value for
 lookups and for extractions in the success case. For the ${if item, the string


@@ -3183,13 +3186,13 @@ if (*s == '}')
   {
   if (type[0] == 'i')
     {
   {
   if (type[0] == 'i')
     {

-    if (yes) *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, US"true", 4);
+    if (yes && !skipping)
+      *yieldptr = string_catn(*yieldptr, US"true", 4);

     }
   else
     {
     }
   else
     {

-    if (yes && lookup_value)
-      *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, lookup_value,
-        Ustrlen(lookup_value));
+    if (yes && lookup_value && !skipping)
+      *yieldptr = string_cat(*yieldptr, lookup_value);

     lookup_value = save_lookup;
     }
   s++;
     lookup_value = save_lookup;
     }
   s++;


@@ -3198,7 +3201,11 @@ if (*s == '}')
 
 /* The first following string must be braced. */
 
 
 /* The first following string must be braced. */
 

-if (*s++ != '{') goto FAILED_CURLY;
+if (*s++ != '{')
+  {
+  errwhere = US"'yes' part did not start with '{'";
+  goto FAILED_CURLY;
+  }

 
 /* Expand the first substring. Forced failures are noticed only if we actually
 want this string. Set skipping in the call in the fail case (this will always
 
 /* Expand the first substring. Forced failures are noticed only if we actually
 want this string. Set skipping in the call in the fail case (this will always


@@ -3207,12 +3214,16 @@ be the case if we were already skipping). */
 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE, resetok);
 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
 expand_string_forcedfail = FALSE;
 sub1 = expand_string_internal(s, TRUE, &s, !yes, TRUE, resetok);
 if (sub1 == NULL && (yes || !expand_string_forcedfail)) goto FAILED;
 expand_string_forcedfail = FALSE;

-if (*s++ != '}') goto FAILED_CURLY;
+if (*s++ != '}')
+  {
+  errwhere = US"'yes' part did not end with '}'";
+  goto FAILED_CURLY;
+  }

 
 /* If we want the first string, add it to the output */
 
 if (yes)
 
 /* If we want the first string, add it to the output */
 
 if (yes)

-  *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub1, Ustrlen(sub1));
+  *yieldptr = string_cat(*yieldptr, sub1);

 
 /* If this is called from a lookup/env or a (cert)extract, we want to restore
 $value to what it was at the start of the item, so that it has this value
 
 /* If this is called from a lookup/env or a (cert)extract, we want to restore
 $value to what it was at the start of the item, so that it has this value


@@ -3233,12 +3244,16 @@ if (*s == '{')
   sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE, resetok);
   if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
   expand_string_forcedfail = FALSE;
   sub2 = expand_string_internal(s+1, TRUE, &s, yes || skipping, TRUE, resetok);
   if (sub2 == NULL && (!yes || !expand_string_forcedfail)) goto FAILED;
   expand_string_forcedfail = FALSE;

-  if (*s++ != '}') goto FAILED_CURLY;
+  if (*s++ != '}')
+    {
+    errwhere = US"'no' part did not start with '{'";
+    goto FAILED_CURLY;
+    }

 
   /* If we want the second string, add it to the output */
 
   if (!yes)
 
   /* If we want the second string, add it to the output */
 
   if (!yes)

-    *yieldptr = string_cat(*yieldptr, sizeptr, ptrptr, sub2, Ustrlen(sub2));
+    *yieldptr = string_cat(*yieldptr, sub2);

   }
 
 /* If there is no second string, but the word "fail" is present when the use of
   }
 
 /* If there is no second string, but the word "fail" is present when the use of


@@ -3256,7 +3271,11 @@ else if (*s != '}')
     if (!yes && !skipping)
       {
       while (isspace(*s)) s++;
     if (!yes && !skipping)
       {
       while (isspace(*s)) s++;

-      if (*s++ != '}') goto FAILED_CURLY;
+      if (*s++ != '}')
+        {
+       errwhere = US"did not close with '}' after forcedfail";
+       goto FAILED_CURLY;
+       }

       expand_string_message =
         string_sprintf("\"%s\" failed and \"fail\" requested", type);
       expand_string_forcedfail = TRUE;
       expand_string_message =
         string_sprintf("\"%s\" failed and \"fail\" requested", type);
       expand_string_forcedfail = TRUE;


@@ -3274,23 +3293,30 @@ else if (*s != '}')
 /* All we have to do now is to check on the final closing brace. */
 
 while (isspace(*s)) s++;
 /* All we have to do now is to check on the final closing brace. */
 
 while (isspace(*s)) s++;

-if (*s++ == '}') goto RETURN;
-
-/* Get here if there is a bracketing failure */
-
-FAILED_CURLY:
-rc++;
-
-/* Get here for other failures */
-
-FAILED:
-rc++;
+if (*s++ != '}')
+  {
+  errwhere = US"did not close with '}'";
+  goto FAILED_CURLY;
+  }

 
 

-/* Update the input pointer value before returning */

 
 RETURN:
 
 RETURN:

+/* Update the input pointer value before returning */

 *sptr = s;
 return rc;
 *sptr = s;
 return rc;

+
+FAILED_CURLY:
+  /* Get here if there is a bracketing failure */
+  expand_string_message = string_sprintf(
+    "curly-bracket problem in conditional yes/no parsing: %s\n"
+    " remaining string is '%s'", errwhere, --s);
+  rc = 2;
+  goto RETURN;
+
+FAILED:
+  /* Get here for other failures */
+  rc = 1;
+  goto RETURN;

 }
 
 
 }
 
 


@@ -3316,7 +3342,7 @@ chash_start(int type, void *base)
 if (type == HMAC_MD5)
   md5_start((md5 *)base);
 else
 if (type == HMAC_MD5)
   md5_start((md5 *)base);
 else

-  sha1_start((sha1 *)base);
+  sha1_start((hctx *)base);

 }
 
 static void
 }
 
 static void


@@ -3325,7 +3351,7 @@ chash_mid(int type, void *base, uschar *string)
 if (type == HMAC_MD5)
   md5_mid((md5 *)base, string);
 else
 if (type == HMAC_MD5)
   md5_mid((md5 *)base, string);
 else

-  sha1_mid((sha1 *)base, string);
+  sha1_mid((hctx *)base, string);

 }
 
 static void
 }
 
 static void


@@ -3334,7 +3360,7 @@ chash_end(int type, void *base, uschar *string, int length, uschar *digest)
 if (type == HMAC_MD5)
   md5_end((md5 *)base, string, length, digest);
 else
 if (type == HMAC_MD5)
   md5_end((md5 *)base, string, length, digest);
 else

-  sha1_end((sha1 *)base, string, length, digest);
+  sha1_end((hctx *)base, string, length, digest);

 }
 
 
 }
 
 


@@ -3391,10 +3417,10 @@ Returns:  pointer to string containing the first three
 static uschar *
 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
 {
 static uschar *
 prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp)
 {

-uschar *hash_source, *p;
-int size = 0,offset = 0,i;
-sha1 sha1_base;
-void *use_base = &sha1_base;
+gstring * hash_source;
+uschar * p;
+int i;
+hctx h;

 uschar innerhash[20];
 uschar finalhash[20];
 uschar innerkey[64];
 uschar innerhash[20];
 uschar finalhash[20];
 uschar innerkey[64];


@@ -3407,12 +3433,13 @@ if (key_num == NULL)
 if (Ustrlen(key) > 64)
   return NULL;
 
 if (Ustrlen(key) > 64)
   return NULL;
 

-hash_source = string_cat(NULL,&size,&offset,key_num,1);
-hash_source = string_cat(hash_source,&size,&offset,daystamp,3);
-hash_source = string_cat(hash_source,&size,&offset,address,Ustrlen(address));
-hash_source[offset] = '\0';
+hash_source = string_catn(NULL, key_num, 1);
+hash_source = string_catn(hash_source, daystamp, 3);
+hash_source = string_cat(hash_source, address);
+(void) string_from_gstring(hash_source);

 
 

-DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source);
+DEBUG(D_expand)
+  debug_printf_indent("prvs: hash source is '%s'\n", hash_source->s);

 
 memset(innerkey, 0x36, 64);
 memset(outerkey, 0x5c, 64);
 
 memset(innerkey, 0x36, 64);
 memset(outerkey, 0x5c, 64);


@@ -3423,13 +3450,13 @@ for (i = 0; i < Ustrlen(key); i++)
   outerkey[i] ^= key[i];
   }
 
   outerkey[i] ^= key[i];
   }
 

-chash_start(HMAC_SHA1, use_base);
-chash_mid(HMAC_SHA1, use_base, innerkey);
-chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash);
+chash_start(HMAC_SHA1, &h);
+chash_mid(HMAC_SHA1, &h, innerkey);
+chash_end(HMAC_SHA1, &h, hash_source->s, hash_source->ptr, innerhash);

 
 

-chash_start(HMAC_SHA1, use_base);
-chash_mid(HMAC_SHA1, use_base, outerkey);
-chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash);
+chash_start(HMAC_SHA1, &h);
+chash_mid(HMAC_SHA1, &h, outerkey);
+chash_end(HMAC_SHA1, &h, innerhash, 20, finalhash);

 
 p = finalhash_hex;
 for (i = 0; i < 3; i++)
 
 p = finalhash_hex;
 for (i = 0; i < 3; i++)


@@ -3455,31 +3482,27 @@ newlines with a given string (optionally).
 
 Arguments:
   f            the FILE
 
 Arguments:
   f            the FILE

-  yield        pointer to the expandable string
-  sizep        pointer to the current size
-  ptrp         pointer to the current position
+  yield        pointer to the expandable string struct

   eol          newline replacement string, or NULL
 
   eol          newline replacement string, or NULL
 

-Returns:       new value of string pointer
+Returns:       new pointer for expandable string, terminated if non-null

 */
 
 */
 

-static uschar *
-cat_file(FILE *f, uschar *yield, int *sizep, int *ptrp, uschar *eol)
+static gstring *
+cat_file(FILE *f, gstring *yield, uschar *eol)

 {
 {

-int eollen = eol ? Ustrlen(eol) : 0;

 uschar buffer[1024];
 
 while (Ufgets(buffer, sizeof(buffer), f))
   {
   int len = Ustrlen(buffer);
   if (eol && buffer[len-1] == '\n') len--;
 uschar buffer[1024];
 
 while (Ufgets(buffer, sizeof(buffer), f))
   {
   int len = Ustrlen(buffer);
   if (eol && buffer[len-1] == '\n') len--;

-  yield = string_cat(yield, sizep, ptrp, buffer, len);
-  if (buffer[len] != 0)
-    yield = string_cat(yield, sizep, ptrp, eol, eollen);
+  yield = string_catn(yield, buffer, len);
+  if (eol && buffer[len])
+    yield = string_cat(yield, eol);

   }
 
   }
 

-if (yield) yield[*ptrp] = 0;
-
+(void) string_from_gstring(yield);

 return yield;
 }
 
 return yield;
 }
 


@@ -3602,7 +3625,7 @@ if (*error == NULL)
     /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
      * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
      * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64].  In fact, -N*-M where
     /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give
      * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which
      * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64].  In fact, -N*-M where

-     * -N*M is INT_MIN will yielf INT_MIN.
+     * -N*M is INT_MIN will yield INT_MIN.

      * Since we don't support floating point, this is somewhat simpler.
      * Ideally, we'd return an error, but since we overflow for all other
      * arithmetic, consistency suggests otherwise, but what's the correct value
      * Since we don't support floating point, this is somewhat simpler.
      * Ideally, we'd return an error, but since we overflow for all other
      * arithmetic, consistency suggests otherwise, but what's the correct value


@@ -3652,13 +3675,20 @@ eval_op_sum(uschar **sptr, BOOL decimal, uschar **error)
 {
 uschar *s = *sptr;
 int_eximarith_t x = eval_op_mult(&s, decimal, error);
 {
 uschar *s = *sptr;
 int_eximarith_t x = eval_op_mult(&s, decimal, error);

-if (*error == NULL)
+if (!*error)

   {
   while (*s == '+' || *s == '-')
     {
     int op = *s++;
     int_eximarith_t y = eval_op_mult(&s, decimal, error);
   {
   while (*s == '+' || *s == '-')
     {
     int op = *s++;
     int_eximarith_t y = eval_op_mult(&s, decimal, error);

-    if (*error != NULL) break;
+    if (*error) break;
+    if (  (x >=   EXIM_ARITH_MAX/2  && x >=   EXIM_ARITH_MAX/2)
+       || (x <= -(EXIM_ARITH_MAX/2) && y <= -(EXIM_ARITH_MAX/2)))
+      {                        /* over-conservative check */
+      *error = op == '+'
+       ? US"overflow in sum" : US"overflow in difference";
+      break;
+      }

     if (op == '+') x += y; else x -= y;
     }
   }
     if (op == '+') x += y; else x -= y;
     }
   }


@@ -3773,7 +3803,7 @@ them here in detail any more.
 We use an internal routine recursively to handle embedded substrings. The
 external function follows. The yield is NULL if the expansion failed, and there
 are two cases: if something collapsed syntactically, or if "fail" was given
 We use an internal routine recursively to handle embedded substrings. The
 external function follows. The yield is NULL if the expansion failed, and there
 are two cases: if something collapsed syntactically, or if "fail" was given

-as the action on a lookup failure. These can be distinguised by looking at the
+as the action on a lookup failure. These can be distinguished by looking at the

 variable expand_string_forcedfail, which is TRUE in the latter case.
 
 The skipping flag is set true when expanding a substring that isn't actually
 variable expand_string_forcedfail, which is TRUE in the latter case.
 
 The skipping flag is set true when expanding a substring that isn't actually


@@ -3820,15 +3850,21 @@ static uschar *
 expand_string_internal(const uschar *string, BOOL ket_ends, const uschar **left,
   BOOL skipping, BOOL honour_dollar, BOOL *resetok_p)
 {
 expand_string_internal(const uschar *string, BOOL ket_ends, const uschar **left,
   BOOL skipping, BOOL honour_dollar, BOOL *resetok_p)
 {

-int ptr = 0;
-int size = Ustrlen(string)+ 64;
+gstring * yield = string_get(Ustrlen(string) + 64);

 int item_type;
 int item_type;

-uschar *yield = store_get(size);

 const uschar *s = string;
 uschar *save_expand_nstring[EXPAND_MAXN+1];
 int save_expand_nlength[EXPAND_MAXN+1];
 BOOL resetok = TRUE;
 
 const uschar *s = string;
 uschar *save_expand_nstring[EXPAND_MAXN+1];
 int save_expand_nlength[EXPAND_MAXN+1];
 BOOL resetok = TRUE;
 

+expand_level++;
+DEBUG(D_expand)
+  debug_printf_indent(UTF8_DOWN_RIGHT "%s: %s\n",
+    skipping
+    ? UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ "scanning"
+    : "considering",
+    string);
+

 expand_string_forcedfail = FALSE;
 expand_string_message = US"";
 
 expand_string_forcedfail = FALSE;
 expand_string_message = US"";
 


@@ -3854,7 +3890,7 @@ while (*s != 0)
       {
       const uschar * t = s + 2;
       for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;
       {
       const uschar * t = s + 2;
       for (s = t; *s != 0; s++) if (*s == '\\' && s[1] == 'N') break;

-      yield = string_cat(yield, &size, &ptr, t, s - t);
+      yield = string_catn(yield, t, s - t);

       if (*s != 0) s += 2;
       }
 
       if (*s != 0) s += 2;
       }
 


@@ -3863,7 +3899,7 @@ while (*s != 0)
       uschar ch[1];
       ch[0] = string_interpret_escape(&s);
       s++;
       uschar ch[1];
       ch[0] = string_interpret_escape(&s);
       s++;

-      yield = string_cat(yield, &size, &ptr, ch, 1);
+      yield = string_catn(yield, ch, 1);

       }
 
     continue;
       }
 
     continue;


@@ -3878,7 +3914,7 @@ while (*s != 0)
 
   if (*s != '$' || !honour_dollar)
     {
 
   if (*s != '$' || !honour_dollar)
     {

-    yield = string_cat(yield, &size, &ptr, s++, 1);
+    yield = string_catn(yield, s++, 1);

     continue;
     }
 
     continue;
     }
 


@@ -3894,17 +3930,20 @@ while (*s != 0)
     {
     int len;
     int newsize = 0;
     {
     int len;
     int newsize = 0;

+    gstring * g = NULL;

 
     s = read_name(name, sizeof(name), s, US"_");
 
     /* If this is the first thing to be expanded, release the pre-allocated
     buffer. */
 
 
     s = read_name(name, sizeof(name), s, US"_");
 
     /* If this is the first thing to be expanded, release the pre-allocated
     buffer. */
 

-    if (ptr == 0 && yield != NULL)
+    if (!yield)
+      g = store_get(sizeof(gstring));
+    else if (yield->ptr == 0)

       {
       if (resetok) store_reset(yield);
       yield = NULL;
       {
       if (resetok) store_reset(yield);
       yield = NULL;

-      size = 0;
+      g = store_get(sizeof(gstring));  /* alloc _before_ calling find_variable() */

       }
 
     /* Header */
       }
 
     /* Header */


@@ -3926,7 +3965,7 @@ while (*s != 0)
       has been omitted. Set a flag to adjust the error message in this case.
       But there is no error here - nothing gets inserted. */
 
       has been omitted. Set a flag to adjust the error message in this case.
       But there is no error here - nothing gets inserted. */
 

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

         {
         if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
         continue;
         {
         if (Ustrchr(name, '}') != NULL) malformed_header = TRUE;
         continue;


@@ -3947,16 +3986,20 @@ while (*s != 0)
     size of that buffer. If this is the first thing in an expansion string,
     yield will be NULL; just point it at the new store instead of copying. Many
     expansion strings contain just one reference, so this is a useful
     size of that buffer. If this is the first thing in an expansion string,
     yield will be NULL; just point it at the new store instead of copying. Many
     expansion strings contain just one reference, so this is a useful

-    optimization, especially for humungous headers. */
+    optimization, especially for humungous headers.  We need to use a gstring
+    structure that is not allocated after that new-buffer, else a later store
+    reset in the middle of the buffer will make it inaccessible. */

 
     len = Ustrlen(value);
 
     len = Ustrlen(value);

-    if (yield == NULL && newsize != 0)
+    if (!yield && newsize != 0)

       {
       {

-      yield = value;
-      size = newsize;
-      ptr = len;
+      yield = g;
+      yield->size = newsize;
+      yield->ptr = len;
+      yield->s = value;

       }
       }

-    else yield = string_cat(yield, &size, &ptr, value, len);
+    else
+      yield = string_catn(yield, value, len);

 
     continue;
     }
 
     continue;
     }


@@ -3966,8 +4009,7 @@ while (*s != 0)
     int n;
     s = read_cnumber(&n, s);
     if (n >= 0 && n <= expand_nmax)
     int n;
     s = read_cnumber(&n, s);
     if (n >= 0 && n <= expand_nmax)

-      yield = string_cat(yield, &size, &ptr, expand_nstring[n],
-        expand_nlength[n]);
+      yield = string_catn(yield, expand_nstring[n], expand_nlength[n]);

     continue;
     }
 
     continue;
     }
 


@@ -3992,8 +4034,7 @@ while (*s != 0)
       goto EXPAND_FAILED;
       }
     if (n >= 0 && n <= expand_nmax)
       goto EXPAND_FAILED;
       }
     if (n >= 0 && n <= expand_nmax)

-      yield = string_cat(yield, &size, &ptr, expand_nstring[n],
-        expand_nlength[n]);
+      yield = string_catn(yield, expand_nstring[n], expand_nlength[n]);

     continue;
     }
 
     continue;
     }
 


@@ -4042,13 +4083,14 @@ while (*s != 0)
        case OK:
        case FAIL:
          DEBUG(D_expand)
        case OK:
        case FAIL:
          DEBUG(D_expand)

-           debug_printf("acl expansion yield: %s\n", user_msg);
+           debug_printf_indent("acl expansion yield: %s\n", user_msg);

          if (user_msg)
          if (user_msg)

-            yield = string_cat(yield, &size, &ptr, user_msg, Ustrlen(user_msg));
+            yield = string_cat(yield, user_msg);

          continue;
 
        case DEFER:
           expand_string_forcedfail = TRUE;
          continue;
 
        case DEFER:
           expand_string_forcedfail = TRUE;

+         /*FALLTHROUGH*/

        default:
           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
          goto EXPAND_FAILED;
        default:
           expand_string_message = string_sprintf("error from acl \"%s\"", sub[0]);
          goto EXPAND_FAILED;


@@ -4068,12 +4110,19 @@ while (*s != 0)
         save_expand_strings(save_expand_nstring, save_expand_nlength);
 
       while (isspace(*s)) s++;
         save_expand_strings(save_expand_nstring, save_expand_nlength);
 
       while (isspace(*s)) s++;

-      next_s = eval_condition(s, &resetok, skipping? NULL : &cond);
+      next_s = eval_condition(s, &resetok, skipping ? NULL : &cond);

       if (next_s == NULL) goto EXPAND_FAILED;  /* message already set */
 
       DEBUG(D_expand)
       if (next_s == NULL) goto EXPAND_FAILED;  /* message already set */
 
       DEBUG(D_expand)

-        debug_printf("condition: %.*s\n   result: %s\n", (int)(next_s - s), s,
-          cond? "true" : "false");
+       {
+        debug_printf_indent(UTF8_VERT_RIGHT UTF8_HORIZ UTF8_HORIZ
+         "condition: %.*s\n",
+         (int)(next_s - s), s);
+        debug_printf_indent(UTF8_VERT_RIGHT UTF8_HORIZ UTF8_HORIZ
+         UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
+         "result: %s\n",
+         cond ? "true" : "false");
+       }

 
       s = next_s;
 
 
       s = next_s;
 


@@ -4086,8 +4135,6 @@ while (*s != 0)
                lookup_value,                 /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */
                lookup_value,                 /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */

-               &size,                        /* output size */
-               &ptr,                         /* output current point */

                US"if",                       /* condition type */
               &resetok))
         {
                US"if",                       /* condition type */
               &resetok))
         {


@@ -4131,11 +4178,13 @@ while (*s != 0)
        goto EXPAND_FAILED;
        }
 
        goto EXPAND_FAILED;
        }
 

-      if (!(encoded = imap_utf7_encode(sub_arg[0], headers_charset,
-                         sub_arg[1][0], sub_arg[2], &expand_string_message)))
-       goto EXPAND_FAILED;

       if (!skipping)
       if (!skipping)

-       yield = string_cat(yield, &size, &ptr, encoded, Ustrlen(encoded));
+       {
+       if (!(encoded = imap_utf7_encode(sub_arg[0], headers_charset,
+                           sub_arg[1][0], sub_arg[2], &expand_string_message)))
+         goto EXPAND_FAILED;
+       yield = string_cat(yield, encoded);
+       }

       continue;
       }
 #endif
       continue;
       }
 #endif


@@ -4171,8 +4220,12 @@ while (*s != 0)
       if (*s == '{')                                   /*}*/
         {
         key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (*s == '{')                                   /*}*/
         {
         key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);

-        if (key == NULL) goto EXPAND_FAILED;           /*{*/
-        if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+        if (!key) goto EXPAND_FAILED;                  /*{{*/
+        if (*s++ != '}')
+         {
+         expand_string_message = US"missing '}' after lookup key";
+         goto EXPAND_FAILED_CURLY;
+         }

         while (isspace(*s)) s++;
         }
       else key = NULL;
         while (isspace(*s)) s++;
         }
       else key = NULL;


@@ -4235,10 +4288,18 @@ while (*s != 0)
       queries that also require a file name (e.g. sqlite), the file name comes
       first. */
 
       queries that also require a file name (e.g. sqlite), the file name comes
       first. */
 

-      if (*s != '{') goto EXPAND_FAILED_CURLY;
+      if (*s != '{')
+        {
+       expand_string_message = US"missing '{' for lookup file-or-query arg";
+       goto EXPAND_FAILED_CURLY;
+       }

       filename = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (filename == NULL) goto EXPAND_FAILED;
       filename = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (filename == NULL) goto EXPAND_FAILED;

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+       expand_string_message = US"missing '}' closing lookup file-or-query arg";
+       goto EXPAND_FAILED_CURLY;
+       }

       while (isspace(*s)) s++;
 
       /* If this isn't a single-key+file lookup, re-arrange the variables
       while (isspace(*s)) s++;
 
       /* If this isn't a single-key+file lookup, re-arrange the variables


@@ -4246,15 +4307,13 @@ while (*s != 0)
       there is just a "key", and no file name. For the special query-style +
       file types, the query (i.e. "key") starts with a file name. */
 
       there is just a "key", and no file name. For the special query-style +
       file types, the query (i.e. "key") starts with a file name. */
 

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

         {
         while (isspace(*filename)) filename++;
         key = filename;
 
         if (mac_islookup(stype, lookup_querystyle))
         {
         while (isspace(*filename)) filename++;
         key = filename;
 
         if (mac_islookup(stype, lookup_querystyle))

-          {

           filename = NULL;
           filename = NULL;

-          }

         else
           {
           if (*filename != '/')
         else
           {
           if (*filename != '/')


@@ -4312,8 +4371,6 @@ while (*s != 0)
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */

-               &size,                        /* output size */
-               &ptr,                         /* output current point */

                US"lookup",                   /* condition type */
               &resetok))
         {
                US"lookup",                   /* condition type */
               &resetok))
         {


@@ -4345,7 +4402,7 @@ while (*s != 0)
     #else   /* EXIM_PERL */
       {
       uschar *sub_arg[EXIM_PERL_MAX_ARGS + 2];
     #else   /* EXIM_PERL */
       {
       uschar *sub_arg[EXIM_PERL_MAX_ARGS + 2];

-      uschar *new_yield;
+      gstring *new_yield;

 
       if ((expand_forbid & RDO_PERL) != 0)
         {
 
       if ((expand_forbid & RDO_PERL) != 0)
         {


@@ -4390,7 +4447,7 @@ while (*s != 0)
       /* Call the function */
 
       sub_arg[EXIM_PERL_MAX_ARGS + 1] = NULL;
       /* Call the function */
 
       sub_arg[EXIM_PERL_MAX_ARGS + 1] = NULL;

-      new_yield = call_perl_cat(yield, &size, &ptr, &expand_string_message,
+      new_yield = call_perl_cat(yield, &expand_string_message,

         sub_arg[0], sub_arg + 1);
 
       /* NULL yield indicates failure; if the message pointer has been set to
         sub_arg[0], sub_arg + 1);
 
       /* NULL yield indicates failure; if the message pointer has been set to


@@ -4437,25 +4494,25 @@ while (*s != 0)
       if (skipping) continue;
 
       /* sub_arg[0] is the address */
       if (skipping) continue;
 
       /* sub_arg[0] is the address */

-      domain = Ustrrchr(sub_arg[0],'@');
-      if ( (domain == NULL) || (domain == sub_arg[0]) || (Ustrlen(domain) == 1) )
+      if (  !(domain = Ustrrchr(sub_arg[0],'@'))
+        || domain == sub_arg[0] || Ustrlen(domain) == 1)

         {
         expand_string_message = US"prvs first argument must be a qualified email address";
         goto EXPAND_FAILED;
         }
 
         {
         expand_string_message = US"prvs first argument must be a qualified email address";
         goto EXPAND_FAILED;
         }
 

-      /* Calculate the hash. The second argument must be a single-digit
+      /* Calculate the hash. The third argument must be a single-digit

       key number, or unset. */
 
       key number, or unset. */
 

-      if (sub_arg[2] != NULL &&
-          (!isdigit(sub_arg[2][0]) || sub_arg[2][1] != 0))
+      if (  sub_arg[2]
+         && (!isdigit(sub_arg[2][0]) || sub_arg[2][1] != 0))

         {
         {

-        expand_string_message = US"prvs second argument must be a single digit";
+        expand_string_message = US"prvs third argument must be a single digit";

         goto EXPAND_FAILED;
         }
 
         goto EXPAND_FAILED;
         }
 

-      p = prvs_hmac_sha1(sub_arg[0],sub_arg[1],sub_arg[2],prvs_daystamp(7));
-      if (p == NULL)
+      p = prvs_hmac_sha1(sub_arg[0], sub_arg[1], sub_arg[2], prvs_daystamp(7));
+      if (!p)

         {
         expand_string_message = US"prvs hmac-sha1 conversion failed";
         goto EXPAND_FAILED;
         {
         expand_string_message = US"prvs hmac-sha1 conversion failed";
         goto EXPAND_FAILED;


@@ -4464,14 +4521,14 @@ while (*s != 0)
       /* Now separate the domain from the local part */
       *domain++ = '\0';
 
       /* Now separate the domain from the local part */
       *domain++ = '\0';
 

-      yield = string_cat(yield,&size,&ptr,US"prvs=",5);
-      string_cat(yield,&size,&ptr,(sub_arg[2] != NULL) ? sub_arg[2] : US"0", 1);
-      string_cat(yield,&size,&ptr,prvs_daystamp(7),3);
-      string_cat(yield,&size,&ptr,p,6);
-      string_cat(yield,&size,&ptr,US"=",1);
-      string_cat(yield,&size,&ptr,sub_arg[0],Ustrlen(sub_arg[0]));
-      string_cat(yield,&size,&ptr,US"@",1);
-      string_cat(yield,&size,&ptr,domain,Ustrlen(domain));
+      yield = string_catn(yield, US"prvs=", 5);
+      yield = string_catn(yield, sub_arg[2] ? sub_arg[2] : US"0", 1);
+      yield = string_catn(yield, prvs_daystamp(7), 3);
+      yield = string_catn(yield, p, 6);
+      yield = string_catn(yield, US"=", 1);
+      yield = string_cat (yield, sub_arg[0]);
+      yield = string_catn(yield, US"@", 1);
+      yield = string_cat (yield, domain);

 
       continue;
       }
 
       continue;
       }


@@ -4481,7 +4538,7 @@ while (*s != 0)
     case EITEM_PRVSCHECK:
       {
       uschar *sub_arg[3];
     case EITEM_PRVSCHECK:
       {
       uschar *sub_arg[3];

-      int mysize = 0, myptr = 0;
+      gstring * g;

       const pcre *re;
       uschar *p;
 
       const pcre *re;
       uschar *p;
 


@@ -4518,17 +4575,17 @@ while (*s != 0)
         uschar *hash = string_copyn(expand_nstring[3],expand_nlength[3]);
         uschar *domain = string_copyn(expand_nstring[5],expand_nlength[5]);
 
         uschar *hash = string_copyn(expand_nstring[3],expand_nlength[3]);
         uschar *domain = string_copyn(expand_nstring[5],expand_nlength[5]);
 

-        DEBUG(D_expand) debug_printf("prvscheck localpart: %s\n", local_part);
-        DEBUG(D_expand) debug_printf("prvscheck key number: %s\n", key_num);
-        DEBUG(D_expand) debug_printf("prvscheck daystamp: %s\n", daystamp);
-        DEBUG(D_expand) debug_printf("prvscheck hash: %s\n", hash);
-        DEBUG(D_expand) debug_printf("prvscheck domain: %s\n", domain);
+        DEBUG(D_expand) debug_printf_indent("prvscheck localpart: %s\n", local_part);
+        DEBUG(D_expand) debug_printf_indent("prvscheck key number: %s\n", key_num);
+        DEBUG(D_expand) debug_printf_indent("prvscheck daystamp: %s\n", daystamp);
+        DEBUG(D_expand) debug_printf_indent("prvscheck hash: %s\n", hash);
+        DEBUG(D_expand) debug_printf_indent("prvscheck domain: %s\n", domain);

 
         /* Set up expansion variables */
 
         /* Set up expansion variables */

-        prvscheck_address = string_cat(NULL, &mysize, &myptr, local_part, Ustrlen(local_part));
-        string_cat(prvscheck_address,&mysize,&myptr,US"@",1);
-        string_cat(prvscheck_address,&mysize,&myptr,domain,Ustrlen(domain));
-        prvscheck_address[myptr] = '\0';
+        g = string_cat (NULL, local_part);
+        g = string_catn(g, US"@", 1);
+        g = string_cat (g, domain);
+        prvscheck_address = string_from_gstring(g);

         prvscheck_keynum = string_copy(key_num);
 
         /* Now expand the second argument */
         prvscheck_keynum = string_copy(key_num);
 
         /* Now expand the second argument */


@@ -4544,14 +4601,14 @@ while (*s != 0)
         p = prvs_hmac_sha1(prvscheck_address, sub_arg[0], prvscheck_keynum,
           daystamp);
 
         p = prvs_hmac_sha1(prvscheck_address, sub_arg[0], prvscheck_keynum,
           daystamp);
 

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

           {
           expand_string_message = US"hmac-sha1 conversion failed";
           goto EXPAND_FAILED;
           }
 
           {
           expand_string_message = US"hmac-sha1 conversion failed";
           goto EXPAND_FAILED;
           }
 

-        DEBUG(D_expand) debug_printf("prvscheck: received hash is %s\n", hash);
-        DEBUG(D_expand) debug_printf("prvscheck:      own hash is %s\n", p);
+        DEBUG(D_expand) debug_printf_indent("prvscheck: received hash is %s\n", hash);
+        DEBUG(D_expand) debug_printf_indent("prvscheck:      own hash is %s\n", p);

 
         if (Ustrcmp(p,hash) == 0)
           {
 
         if (Ustrcmp(p,hash) == 0)
           {


@@ -4569,18 +4626,18 @@ while (*s != 0)
           if (iexpire >= inow)
             {
             prvscheck_result = US"1";
           if (iexpire >= inow)
             {
             prvscheck_result = US"1";

-            DEBUG(D_expand) debug_printf("prvscheck: success, $pvrs_result set to 1\n");
+            DEBUG(D_expand) debug_printf_indent("prvscheck: success, $pvrs_result set to 1\n");

             }
             }

-            else
+         else

             {
             prvscheck_result = NULL;
             {
             prvscheck_result = NULL;

-            DEBUG(D_expand) debug_printf("prvscheck: signature expired, $pvrs_result unset\n");
+            DEBUG(D_expand) debug_printf_indent("prvscheck: signature expired, $pvrs_result unset\n");

             }
           }
         else
           {
           prvscheck_result = NULL;
             }
           }
         else
           {
           prvscheck_result = NULL;

-          DEBUG(D_expand) debug_printf("prvscheck: hash failure, $pvrs_result unset\n");
+          DEBUG(D_expand) debug_printf_indent("prvscheck: hash failure, $pvrs_result unset\n");

           }
 
         /* Now expand the final argument. We leave this till now so that
           }
 
         /* Now expand the final argument. We leave this till now so that


@@ -4593,10 +4650,8 @@ while (*s != 0)
           case 3: goto EXPAND_FAILED;
           }
 
           case 3: goto EXPAND_FAILED;
           }
 

-        if (sub_arg[0] == NULL || *sub_arg[0] == '\0')
-          yield = string_cat(yield,&size,&ptr,prvscheck_address,Ustrlen(prvscheck_address));
-        else
-          yield = string_cat(yield,&size,&ptr,sub_arg[0],Ustrlen(sub_arg[0]));
+       yield = string_cat(yield,
+         !sub_arg[0] || !*sub_arg[0] ? prvscheck_address : sub_arg[0]);

 
         /* Reset the "internal" variables afterwards, because they are in
         dynamic store that will be reclaimed if the expansion succeeded. */
 
         /* Reset the "internal" variables afterwards, because they are in
         dynamic store that will be reclaimed if the expansion succeeded. */


@@ -4605,7 +4660,6 @@ while (*s != 0)
         prvscheck_keynum = NULL;
         }
       else
         prvscheck_keynum = NULL;
         }
       else

-        {

         /* Does not look like a prvs encoded address, return the empty string.
            We need to make sure all subs are expanded first, so as to skip over
            the entire item. */
         /* Does not look like a prvs encoded address, return the empty string.
            We need to make sure all subs are expanded first, so as to skip over
            the entire item. */


@@ -4616,7 +4670,6 @@ while (*s != 0)
           case 2:
           case 3: goto EXPAND_FAILED;
           }
           case 2:
           case 3: goto EXPAND_FAILED;
           }

-        }

 
       continue;
       }
 
       continue;
       }


@@ -4647,31 +4700,32 @@ while (*s != 0)
 
       /* Open the file and read it */
 
 
       /* Open the file and read it */
 

-      f = Ufopen(sub_arg[0], "rb");
-      if (f == NULL)
+      if (!(f = Ufopen(sub_arg[0], "rb")))

         {
         expand_string_message = string_open_failed(errno, "%s", sub_arg[0]);
         goto EXPAND_FAILED;
         }
 
         {
         expand_string_message = string_open_failed(errno, "%s", sub_arg[0]);
         goto EXPAND_FAILED;
         }
 

-      yield = cat_file(f, yield, &size, &ptr, sub_arg[1]);
+      yield = cat_file(f, yield, sub_arg[1]);

       (void)fclose(f);
       continue;
       }
 
       (void)fclose(f);
       continue;
       }
 

-    /* Handle "readsocket" to insert data from a Unix domain socket */
+    /* Handle "readsocket" to insert data from a socket, either
+    Inet or Unix domain */

 
     case EITEM_READSOCK:
       {
       int fd;
       int timeout = 5;
 
     case EITEM_READSOCK:
       {
       int fd;
       int timeout = 5;

-      int save_ptr = ptr;
+      int save_ptr = yield->ptr;

       FILE *f;
       FILE *f;

-      struct sockaddr_un sockun;         /* don't call this "sun" ! */

       uschar *arg;
       uschar *sub_arg[4];
       uschar *arg;
       uschar *sub_arg[4];

+      BOOL do_shutdown = TRUE;
+      blob reqstr;

 
 

-      if ((expand_forbid & RDO_READSOCK) != 0)
+      if (expand_forbid & RDO_READSOCK)

         {
         expand_string_message = US"socket insertions are not permitted";
         goto EXPAND_FAILED;
         {
         expand_string_message = US"socket insertions are not permitted";
         goto EXPAND_FAILED;


@@ -4687,17 +4741,32 @@ while (*s != 0)
         case 3: goto EXPAND_FAILED;
         }
 
         case 3: goto EXPAND_FAILED;
         }
 

-      /* Sort out timeout, if given */
+      /* Grab the request string, if any */
+
+      reqstr.data = sub_arg[1];
+      reqstr.len = Ustrlen(sub_arg[1]);

 
 

-      if (sub_arg[2] != NULL)
+      /* Sort out timeout, if given.  The second arg is a list with the first element
+      being a time value.  Any more are options of form "name=value".  Currently the
+      only option recognised is "shutdown". */
+
+      if (sub_arg[2])

         {
         {

-        timeout = readconf_readtime(sub_arg[2], 0, FALSE);
-        if (timeout < 0)
+       const uschar * list = sub_arg[2];
+       uschar * item;
+       int sep = 0;
+
+       item = string_nextinlist(&list, &sep, NULL, 0);
+        if ((timeout = readconf_readtime(item, 0, FALSE)) < 0)

           {
           {

-          expand_string_message = string_sprintf("bad time value %s",
-            sub_arg[2]);
+          expand_string_message = string_sprintf("bad time value %s", item);

           goto EXPAND_FAILED;
           }
           goto EXPAND_FAILED;
           }

+
+       while ((item = string_nextinlist(&list, &sep, NULL, 0)))
+         if (Ustrncmp(item, US"shutdown=", 9) == 0)
+           if (Ustrcmp(item + 9, US"no") == 0)
+             do_shutdown = FALSE;

         }
       else sub_arg[3] = NULL;                     /* No eol if no timeout */
 
         }
       else sub_arg[3] = NULL;                     /* No eol if no timeout */
 


@@ -4711,12 +4780,12 @@ while (*s != 0)
         if (Ustrncmp(sub_arg[0], "inet:", 5) == 0)
           {
           int port;
         if (Ustrncmp(sub_arg[0], "inet:", 5) == 0)
           {
           int port;

-          uschar *server_name = sub_arg[0] + 5;
-          uschar *port_name = Ustrrchr(server_name, ':');
+          uschar * server_name = sub_arg[0] + 5;
+          uschar * port_name = Ustrrchr(server_name, ':');

 
           /* Sort out the port */
 
 
           /* Sort out the port */
 

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

             {
             expand_string_message =
               string_sprintf("missing port for readsocket %s", sub_arg[0]);
             {
             expand_string_message =
               string_sprintf("missing port for readsocket %s", sub_arg[0]);


@@ -4738,7 +4807,7 @@ while (*s != 0)
           else
             {
             struct servent *service_info = getservbyname(CS port_name, "tcp");
           else
             {
             struct servent *service_info = getservbyname(CS port_name, "tcp");

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

               {
               expand_string_message = string_sprintf("unknown port \"%s\"",
                 port_name);
               {
               expand_string_message = string_sprintf("unknown port \"%s\"",
                 port_name);


@@ -4747,16 +4816,21 @@ while (*s != 0)
             port = ntohs(service_info->s_port);
             }
 
             port = ntohs(service_info->s_port);
             }
 

-         if ((fd = ip_connectedsocket(SOCK_STREAM, server_name, port, port,
-                 timeout, NULL, &expand_string_message)) < 0)
+         fd = ip_connectedsocket(SOCK_STREAM, server_name, port, port,
+                 timeout, NULL, &expand_string_message, &reqstr);
+         callout_address = NULL;
+         if (fd < 0)

               goto SOCK_FAIL;
               goto SOCK_FAIL;

+         reqstr.len = 0;

           }
 
         /* Handle a Unix domain socket */
 
         else
           {
           }
 
         /* Handle a Unix domain socket */
 
         else
           {

+         struct sockaddr_un sockun;         /* don't call this "sun" ! */

           int rc;
           int rc;

+

           if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
             {
             expand_string_message = string_sprintf("failed to create socket: %s",
           if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
             {
             expand_string_message = string_sprintf("failed to create socket: %s",


@@ -4785,19 +4859,18 @@ while (*s != 0)
             }
           }
 
             }
           }
 

-        DEBUG(D_expand) debug_printf("connected to socket %s\n", sub_arg[0]);
+        DEBUG(D_expand) debug_printf_indent("connected to socket %s\n", sub_arg[0]);

 
        /* Allow sequencing of test actions */
        if (running_in_test_harness) millisleep(100);
 
 
        /* Allow sequencing of test actions */
        if (running_in_test_harness) millisleep(100);
 

-        /* Write the request string, if not empty */
+        /* Write the request string, if not empty or already done */

 
 

-        if (sub_arg[1][0] != 0)
+        if (reqstr.len)

           {
           {

-          int len = Ustrlen(sub_arg[1]);
-          DEBUG(D_expand) debug_printf("writing \"%s\" to socket\n",
-            sub_arg[1]);
-          if (write(fd, sub_arg[1], len) != len)
+          DEBUG(D_expand) debug_printf_indent("writing \"%s\" to socket\n",
+            reqstr.data);
+          if (write(fd, reqstr.data, reqstr.len) != reqstr.len)

             {
             expand_string_message = string_sprintf("request write to socket "
               "failed: %s", strerror(errno));
             {
             expand_string_message = string_sprintf("request write to socket "
               "failed: %s", strerror(errno));


@@ -4809,9 +4882,9 @@ while (*s != 0)
         recognise that it is their turn to do some work. Just in case some
         system doesn't have this function, make it conditional. */
 
         recognise that it is their turn to do some work. Just in case some
         system doesn't have this function, make it conditional. */
 

-        #ifdef SHUT_WR
-        shutdown(fd, SHUT_WR);
-        #endif
+#ifdef SHUT_WR
+       if (do_shutdown) shutdown(fd, SHUT_WR);
+#endif

 
        if (running_in_test_harness) millisleep(100);
 
 
        if (running_in_test_harness) millisleep(100);
 


@@ -4821,7 +4894,7 @@ while (*s != 0)
         f = fdopen(fd, "rb");
         sigalrm_seen = FALSE;
         alarm(timeout);
         f = fdopen(fd, "rb");
         sigalrm_seen = FALSE;
         alarm(timeout);

-        yield = cat_file(f, yield, &size, &ptr, sub_arg[3]);
+        yield = cat_file(f, yield, sub_arg[3]);

         alarm(0);
         (void)fclose(f);
 
         alarm(0);
         (void)fclose(f);
 


@@ -4830,7 +4903,7 @@ while (*s != 0)
 
         if (sigalrm_seen)
           {
 
         if (sigalrm_seen)
           {

-          ptr = save_ptr;
+          yield->ptr = save_ptr;

           expand_string_message = US "socket read timed out";
           goto SOCK_FAIL;
           }
           expand_string_message = US "socket read timed out";
           goto SOCK_FAIL;
           }


@@ -4843,26 +4916,39 @@ while (*s != 0)
         {
         if (expand_string_internal(s+1, TRUE, &s, TRUE, TRUE, &resetok) == NULL)
           goto EXPAND_FAILED;
         {
         if (expand_string_internal(s+1, TRUE, &s, TRUE, TRUE, &resetok) == NULL)
           goto EXPAND_FAILED;

-        if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+        if (*s++ != '}')
+         {
+         expand_string_message = US"missing '}' closing failstring for readsocket";
+         goto EXPAND_FAILED_CURLY;
+         }

         while (isspace(*s)) s++;
         }
         while (isspace(*s)) s++;
         }

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+
+    READSOCK_DONE:
+      if (*s++ != '}')
+        {
+       expand_string_message = US"missing '}' closing readsocket";
+       goto EXPAND_FAILED_CURLY;
+       }

       continue;
 
       /* Come here on failure to create socket, connect socket, write to the
       socket, or timeout on reading. If another substring follows, expand and
       use it. Otherwise, those conditions give expand errors. */
 
       continue;
 
       /* Come here on failure to create socket, connect socket, write to the
       socket, or timeout on reading. If another substring follows, expand and
       use it. Otherwise, those conditions give expand errors. */
 

-      SOCK_FAIL:
+    SOCK_FAIL:

       if (*s != '{') goto EXPAND_FAILED;
       DEBUG(D_any) debug_printf("%s\n", expand_string_message);
       if (*s != '{') goto EXPAND_FAILED;
       DEBUG(D_any) debug_printf("%s\n", expand_string_message);

-      arg = expand_string_internal(s+1, TRUE, &s, FALSE, TRUE, &resetok);
-      if (arg == NULL) goto EXPAND_FAILED;
-      yield = string_cat(yield, &size, &ptr, arg, Ustrlen(arg));
-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (!(arg = expand_string_internal(s+1, TRUE, &s, FALSE, TRUE, &resetok)))
+        goto EXPAND_FAILED;
+      yield = string_cat(yield, arg);
+      if (*s++ != '}')
+        {
+       expand_string_message = US"missing '}' closing failstring for readsocket";
+       goto EXPAND_FAILED_CURLY;
+       }

       while (isspace(*s)) s++;
       while (isspace(*s)) s++;

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
-      continue;
+      goto READSOCK_DONE;

       }
 
     /* Handle "run" to execute a program. */
       }
 
     /* Handle "run" to execute a program. */


@@ -4874,7 +4960,6 @@ while (*s != 0)
       const uschar **argv;
       pid_t pid;
       int fd_in, fd_out;
       const uschar **argv;
       pid_t pid;
       int fd_in, fd_out;

-      int lsize = 0, lptr = 0;

 
       if ((expand_forbid & RDO_RUN) != 0)
         {
 
       if ((expand_forbid & RDO_RUN) != 0)
         {


@@ -4883,16 +4968,25 @@ while (*s != 0)
         }
 
       while (isspace(*s)) s++;
         }
 
       while (isspace(*s)) s++;

-      if (*s != '{') goto EXPAND_FAILED_CURLY;
+      if (*s != '{')
+        {
+       expand_string_message = US"missing '{' for command arg of run";
+       goto EXPAND_FAILED_CURLY;
+       }

       arg = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (arg == NULL) goto EXPAND_FAILED;
       while (isspace(*s)) s++;
       arg = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (arg == NULL) goto EXPAND_FAILED;
       while (isspace(*s)) s++;

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+       expand_string_message = US"missing '}' closing command arg of run";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       if (skipping)   /* Just pretend it worked when we're skipping */
 
       if (skipping)   /* Just pretend it worked when we're skipping */

-        {
+       {

         runrc = 0;
         runrc = 0;

-        }
+       lookup_value = NULL;
+       }

       else
         {
         if (!transport_set_up_command(&argv,    /* anchor for arg list */
       else
         {
         if (!transport_set_up_command(&argv,    /* anchor for arg list */


@@ -4926,7 +5020,7 @@ while (*s != 0)
         f = fdopen(fd_out, "rb");
         sigalrm_seen = FALSE;
         alarm(60);
         f = fdopen(fd_out, "rb");
         sigalrm_seen = FALSE;
         alarm(60);

-        lookup_value = cat_file(f, NULL, &lsize, &lptr, NULL);
+       lookup_value = string_from_gstring(cat_file(f, NULL, NULL));

         alarm(0);
         (void)fclose(f);
 
         alarm(0);
         (void)fclose(f);
 


@@ -4934,9 +5028,9 @@ while (*s != 0)
         return code for serious disasters. Simple non-zero returns are passed on.
         */
 
         return code for serious disasters. Simple non-zero returns are passed on.
         */
 

-        if (sigalrm_seen == TRUE || (runrc = child_close(pid, 30)) < 0)
+        if (sigalrm_seen || (runrc = child_close(pid, 30)) < 0)

           {
           {

-          if (sigalrm_seen == TRUE || runrc == -256)
+          if (sigalrm_seen || runrc == -256)

             {
             expand_string_message = string_sprintf("command timed out");
             killpg(pid, SIGKILL);       /* Kill the whole process group */
             {
             expand_string_message = string_sprintf("command timed out");
             killpg(pid, SIGKILL);       /* Kill the whole process group */


@@ -4962,8 +5056,6 @@ while (*s != 0)
                lookup_value,                 /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */
                lookup_value,                 /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */

-               &size,                        /* output size */
-               &ptr,                         /* output current point */

                US"run",                      /* condition type */
               &resetok))
         {
                US"run",                      /* condition type */
               &resetok))
         {


@@ -4978,7 +5070,7 @@ while (*s != 0)
 
     case EITEM_TR:
       {
 
     case EITEM_TR:
       {

-      int oldptr = ptr;
+      int oldptr = yield->ptr;

       int o2m;
       uschar *sub[3];
 
       int o2m;
       uschar *sub[3];
 


@@ -4989,16 +5081,16 @@ while (*s != 0)
         case 3: goto EXPAND_FAILED;
         }
 
         case 3: goto EXPAND_FAILED;
         }
 

-      yield = string_cat(yield, &size, &ptr, sub[0], Ustrlen(sub[0]));
+      yield = string_cat(yield, sub[0]);

       o2m = Ustrlen(sub[2]) - 1;
 
       o2m = Ustrlen(sub[2]) - 1;
 

-      if (o2m >= 0) for (; oldptr < ptr; oldptr++)
+      if (o2m >= 0) for (; oldptr < yield->ptr; oldptr++)

         {
         {

-        uschar *m = Ustrrchr(sub[1], yield[oldptr]);
+        uschar *m = Ustrrchr(sub[1], yield->s[oldptr]);

         if (m != NULL)
           {
           int o = m - sub[1];
         if (m != NULL)
           {
           int o = m - sub[1];

-          yield[oldptr] = sub[2][(o < o2m)? o : o2m];
+          yield->s[oldptr] = sub[2][(o < o2m)? o : o2m];

           }
         }
 
           }
         }
 


@@ -5066,7 +5158,7 @@ while (*s != 0)
           extract_substr(sub[2], val[0], val[1], &len);
 
       if (ret == NULL) goto EXPAND_FAILED;
           extract_substr(sub[2], val[0], val[1], &len);
 
       if (ret == NULL) goto EXPAND_FAILED;

-      yield = string_cat(yield, &size, &ptr, ret, len);
+      yield = string_catn(yield, ret, len);

       continue;
       }
 
       continue;
       }
 


@@ -5084,7 +5176,7 @@ while (*s != 0)
       {
       uschar *sub[3];
       md5 md5_base;
       {
       uschar *sub[3];
       md5 md5_base;

-      sha1 sha1_base;
+      hctx sha1_ctx;

       void *use_base;
       int type, i;
       int hashlen;      /* Number of octets for the hash algorithm's output */
       void *use_base;
       int type, i;
       int hashlen;      /* Number of octets for the hash algorithm's output */


@@ -5106,79 +5198,81 @@ while (*s != 0)
         case 3: goto EXPAND_FAILED;
         }
 
         case 3: goto EXPAND_FAILED;
         }
 

-      if (Ustrcmp(sub[0], "md5") == 0)
-        {
-        type = HMAC_MD5;
-        use_base = &md5_base;
-        hashlen = 16;
-        hashblocklen = 64;
-        }
-      else if (Ustrcmp(sub[0], "sha1") == 0)
-        {
-        type = HMAC_SHA1;
-        use_base = &sha1_base;
-        hashlen = 20;
-        hashblocklen = 64;
-        }
-      else
-        {
-        expand_string_message =
-          string_sprintf("hmac algorithm \"%s\" is not recognised", sub[0]);
-        goto EXPAND_FAILED;
-        }
+      if (!skipping)
+       {
+       if (Ustrcmp(sub[0], "md5") == 0)
+         {
+         type = HMAC_MD5;
+         use_base = &md5_base;
+         hashlen = 16;
+         hashblocklen = 64;
+         }
+       else if (Ustrcmp(sub[0], "sha1") == 0)
+         {
+         type = HMAC_SHA1;
+         use_base = &sha1_ctx;
+         hashlen = 20;
+         hashblocklen = 64;
+         }
+       else
+         {
+         expand_string_message =
+           string_sprintf("hmac algorithm \"%s\" is not recognised", sub[0]);
+         goto EXPAND_FAILED;
+         }

 
 

-      keyptr = sub[1];
-      keylen = Ustrlen(keyptr);
+       keyptr = sub[1];
+       keylen = Ustrlen(keyptr);

 
 

-      /* If the key is longer than the hash block length, then hash the key
-      first */
+       /* If the key is longer than the hash block length, then hash the key
+       first */

 
 

-      if (keylen > hashblocklen)
-        {
-        chash_start(type, use_base);
-        chash_end(type, use_base, keyptr, keylen, keyhash);
-        keyptr = keyhash;
-        keylen = hashlen;
-        }
+       if (keylen > hashblocklen)
+         {
+         chash_start(type, use_base);
+         chash_end(type, use_base, keyptr, keylen, keyhash);
+         keyptr = keyhash;
+         keylen = hashlen;
+         }

 
 

-      /* Now make the inner and outer key values */
+       /* Now make the inner and outer key values */

 
 

-      memset(innerkey, 0x36, hashblocklen);
-      memset(outerkey, 0x5c, hashblocklen);
+       memset(innerkey, 0x36, hashblocklen);
+       memset(outerkey, 0x5c, hashblocklen);

 
 

-      for (i = 0; i < keylen; i++)
-        {
-        innerkey[i] ^= keyptr[i];
-        outerkey[i] ^= keyptr[i];
-        }
+       for (i = 0; i < keylen; i++)
+         {
+         innerkey[i] ^= keyptr[i];
+         outerkey[i] ^= keyptr[i];
+         }

 
 

-      /* Now do the hashes */
+       /* Now do the hashes */

 
 

-      chash_start(type, use_base);
-      chash_mid(type, use_base, innerkey);
-      chash_end(type, use_base, sub[2], Ustrlen(sub[2]), innerhash);
+       chash_start(type, use_base);
+       chash_mid(type, use_base, innerkey);
+       chash_end(type, use_base, sub[2], Ustrlen(sub[2]), innerhash);

 
 

-      chash_start(type, use_base);
-      chash_mid(type, use_base, outerkey);
-      chash_end(type, use_base, innerhash, hashlen, finalhash);
+       chash_start(type, use_base);
+       chash_mid(type, use_base, outerkey);
+       chash_end(type, use_base, innerhash, hashlen, finalhash);

 
 

-      /* Encode the final hash as a hex string */
+       /* Encode the final hash as a hex string */

 
 

-      p = finalhash_hex;
-      for (i = 0; i < hashlen; i++)
-        {
-        *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
-        *p++ = hex_digits[finalhash[i] & 0x0f];
-        }
+       p = finalhash_hex;
+       for (i = 0; i < hashlen; i++)
+         {
+         *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4];
+         *p++ = hex_digits[finalhash[i] & 0x0f];
+         }

 
 

-      DEBUG(D_any) debug_printf("HMAC[%s](%.*s,%.*s)=%.*s\n", sub[0],
-        (int)keylen, keyptr, Ustrlen(sub[2]), sub[2], hashlen*2, finalhash_hex);
+       DEBUG(D_any) debug_printf("HMAC[%s](%.*s,%s)=%.*s\n",
+         sub[0], (int)keylen, keyptr, sub[2], hashlen*2, finalhash_hex);

 
 

-      yield = string_cat(yield, &size, &ptr, finalhash_hex, hashlen*2);
+       yield = string_catn(yield, finalhash_hex, hashlen*2);
+       }
+      continue;

       }
 
       }
 

-    continue;
-

     /* Handle global substitution for "sg" - like Perl's s/xxx/yyy/g operator.
     We have to save the numerical variables and restore them afterwards. */
 
     /* Handle global substitution for "sg" - like Perl's s/xxx/yyy/g operator.
     We have to save the numerical variables and restore them afterwards. */
 


@@ -5245,7 +5339,7 @@ while (*s != 0)
             emptyopt = 0;
             continue;
             }
             emptyopt = 0;
             continue;
             }

-          yield = string_cat(yield, &size, &ptr, subject+moffset, slen-moffset);
+          yield = string_catn(yield, subject+moffset, slen-moffset);

           break;
           }
 
           break;
           }
 


@@ -5262,11 +5356,10 @@ while (*s != 0)
 
         /* Copy the characters before the match, plus the expanded insertion. */
 
 
         /* Copy the characters before the match, plus the expanded insertion. */
 

-        yield = string_cat(yield, &size, &ptr, subject + moffset,
-          ovector[0] - moffset);
+        yield = string_catn(yield, subject + moffset, ovector[0] - moffset);

         insert = expand_string(sub[2]);
         if (insert == NULL) goto EXPAND_FAILED;
         insert = expand_string(sub[2]);
         if (insert == NULL) goto EXPAND_FAILED;

-        yield = string_cat(yield, &size, &ptr, insert, Ustrlen(insert));
+        yield = string_cat(yield, insert);

 
         moffset = ovector[1];
         moffsetextra = 0;
 
         moffset = ovector[1];
         moffsetextra = 0;


@@ -5299,7 +5392,7 @@ while (*s != 0)
     case EITEM_EXTRACT:
       {
       int i;
     case EITEM_EXTRACT:
       {
       int i;

-      int j = 2;
+      int j;

       int field_number = 1;
       BOOL field_number_set = FALSE;
       uschar *save_lookup_value = lookup_value;
       int field_number = 1;
       BOOL field_number_set = FALSE;
       uschar *save_lookup_value = lookup_value;


@@ -5309,30 +5402,49 @@ while (*s != 0)
 
       /* While skipping we cannot rely on the data for expansions being
       available (eg. $item) hence cannot decide on numeric vs. keyed.
 
       /* While skipping we cannot rely on the data for expansions being
       available (eg. $item) hence cannot decide on numeric vs. keyed.

-      Just read as many arguments as there are. */
+      Read a maximum of 5 arguments (including the yes/no) */

 
       if (skipping)
        {
         while (isspace(*s)) s++;
 
       if (skipping)
        {
         while (isspace(*s)) s++;

-        while (*s == '{')
+        for (j = 5; j > 0 && *s == '{'; j--)

          {
           if (!expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok))
            goto EXPAND_FAILED;                                 /*{*/
          {
           if (!expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok))
            goto EXPAND_FAILED;                                 /*{*/

-          if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+          if (*s++ != '}')
+           {
+           expand_string_message = US"missing '{' for arg of extract";
+           goto EXPAND_FAILED_CURLY;
+           }
+         while (isspace(*s)) s++;
+         }
+       if (  Ustrncmp(s, "fail", 4) == 0
+          && (s[4] == '}' || s[4] == ' ' || s[4] == '\t' || !s[4])
+          )
+         {
+         s += 4;

          while (isspace(*s)) s++;
          }
        if (*s != '}')
          while (isspace(*s)) s++;
          }
        if (*s != '}')

+         {
+         expand_string_message = US"missing '}' closing extract";

          goto EXPAND_FAILED_CURLY;
          goto EXPAND_FAILED_CURLY;

+         }

        }
 
        }
 

-      else for (i = 0; i < j; i++) /* Read the proper number of arguments */
+      else for (i = 0, j = 2; i < j; i++) /* Read the proper number of arguments */

         {
         while (isspace(*s)) s++;
         if (*s == '{')                                                 /*}*/
           {
           sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
           if (sub[i] == NULL) goto EXPAND_FAILED;              /*{*/
         {
         while (isspace(*s)) s++;
         if (*s == '{')                                                 /*}*/
           {
           sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
           if (sub[i] == NULL) goto EXPAND_FAILED;              /*{*/

-          if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+          if (*s++ != '}')
+           {
+           expand_string_message = string_sprintf(
+             "missing '}' closing arg %d of extract", i+1);
+           goto EXPAND_FAILED_CURLY;
+           }

 
           /* After removal of leading and trailing white space, the first
           argument must not be empty; if it consists entirely of digits
 
           /* After removal of leading and trailing white space, the first
           argument must not be empty; if it consists entirely of digits


@@ -5373,7 +5485,12 @@ while (*s != 0)
              }
             }
           }
              }
             }
           }

-        else goto EXPAND_FAILED_CURLY;
+        else
+         {
+         expand_string_message = string_sprintf(
+           "missing '{' for arg %d of extract", i+1);
+         goto EXPAND_FAILED_CURLY;
+         }

         }
 
       /* Extract either the numbered or the keyed substring into $value. If
         }
 
       /* Extract either the numbered or the keyed substring into $value. If


@@ -5392,8 +5509,6 @@ while (*s != 0)
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */

-               &size,                        /* output size */
-               &ptr,                         /* output current point */

                US"extract",                  /* condition type */
               &resetok))
         {
                US"extract",                  /* condition type */
               &resetok))
         {


@@ -5426,11 +5541,20 @@ while (*s != 0)
         {
         while (isspace(*s)) s++;
         if (*s != '{')                                 /*}*/
         {
         while (isspace(*s)) s++;
         if (*s != '{')                                 /*}*/

+         {
+         expand_string_message = string_sprintf(
+           "missing '{' for arg %d of listextract", i+1);

          goto EXPAND_FAILED_CURLY;
          goto EXPAND_FAILED_CURLY;

+         }

 
        sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
        if (!sub[i])     goto EXPAND_FAILED;            /*{*/
 
        sub[i] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
        if (!sub[i])     goto EXPAND_FAILED;            /*{*/

-       if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+       if (*s++ != '}')
+         {
+         expand_string_message = string_sprintf(
+           "missing '}' closing arg %d of listextract", i+1);
+         goto EXPAND_FAILED_CURLY;
+         }

 
        /* After removal of leading and trailing white space, the first
        argument must be numeric and nonempty. */
 
        /* After removal of leading and trailing white space, the first
        argument must be numeric and nonempty. */


@@ -5485,8 +5609,6 @@ while (*s != 0)
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */

-               &size,                        /* output size */
-               &ptr,                         /* output current point */

                US"listextract",              /* condition type */
               &resetok))
         {
                US"listextract",              /* condition type */
               &resetok))
         {


@@ -5513,10 +5635,17 @@ while (*s != 0)
       /* Read the field argument */
       while (isspace(*s)) s++;
       if (*s != '{')                                   /*}*/
       /* Read the field argument */
       while (isspace(*s)) s++;
       if (*s != '{')                                   /*}*/

+       {
+       expand_string_message = US"missing '{' for field arg of certextract";

        goto EXPAND_FAILED_CURLY;
        goto EXPAND_FAILED_CURLY;

+       }

       sub[0] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (!sub[0])     goto EXPAND_FAILED;             /*{*/
       sub[0] = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (!sub[0])     goto EXPAND_FAILED;             /*{*/

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+       expand_string_message = US"missing '}' closing field arg of certextract";
+       goto EXPAND_FAILED_CURLY;
+       }

       /* strip spaces fore & aft */
       {
       int len;
       /* strip spaces fore & aft */
       {
       int len;


@@ -5533,7 +5662,10 @@ while (*s != 0)
       /* inspect the cert argument */
       while (isspace(*s)) s++;
       if (*s != '{')                                   /*}*/
       /* inspect the cert argument */
       while (isspace(*s)) s++;
       if (*s != '{')                                   /*}*/

+       {
+       expand_string_message = US"missing '{' for cert variable arg of certextract";

        goto EXPAND_FAILED_CURLY;
        goto EXPAND_FAILED_CURLY;

+       }

       if (*++s != '$')
         {
        expand_string_message = US"second argument of \"certextract\" must "
       if (*++s != '$')
         {
        expand_string_message = US"second argument of \"certextract\" must "


@@ -5542,7 +5674,11 @@ while (*s != 0)
        }
       sub[1] = expand_string_internal(s+1, TRUE, &s, skipping, FALSE, &resetok);
       if (!sub[1])     goto EXPAND_FAILED;             /*{*/
        }
       sub[1] = expand_string_internal(s+1, TRUE, &s, skipping, FALSE, &resetok);
       if (!sub[1])     goto EXPAND_FAILED;             /*{*/

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+       expand_string_message = US"missing '}' closing cert variable arg of certextract";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       if (skipping)
        lookup_value = NULL;
 
       if (skipping)
        lookup_value = NULL;


@@ -5557,8 +5693,6 @@ while (*s != 0)
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */

-               &size,                        /* output size */
-               &ptr,                         /* output current point */

                US"certextract",              /* condition type */
               &resetok))
         {
                US"certextract",              /* condition type */
               &resetok))
         {


@@ -5579,32 +5713,55 @@ while (*s != 0)
     case EITEM_REDUCE:
       {
       int sep = 0;
     case EITEM_REDUCE:
       {
       int sep = 0;

-      int save_ptr = ptr;
+      int save_ptr = yield->ptr;

       uschar outsep[2] = { '\0', '\0' };
       const uschar *list, *expr, *temp;
       uschar *save_iterate_item = iterate_item;
       uschar *save_lookup_value = lookup_value;
 
       while (isspace(*s)) s++;
       uschar outsep[2] = { '\0', '\0' };
       const uschar *list, *expr, *temp;
       uschar *save_iterate_item = iterate_item;
       uschar *save_lookup_value = lookup_value;
 
       while (isspace(*s)) s++;

-      if (*s++ != '{') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '{')
+        {
+       expand_string_message =
+         string_sprintf("missing '{' for first arg of %s", name);
+       goto EXPAND_FAILED_CURLY;
+       }

 
       list = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
       if (list == NULL) goto EXPAND_FAILED;
 
       list = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
       if (list == NULL) goto EXPAND_FAILED;

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+       expand_string_message =
+         string_sprintf("missing '}' closing first arg of %s", name);
+       goto EXPAND_FAILED_CURLY;
+       }

 
       if (item_type == EITEM_REDUCE)
         {
        uschar * t;
         while (isspace(*s)) s++;
 
       if (item_type == EITEM_REDUCE)
         {
        uschar * t;
         while (isspace(*s)) s++;

-        if (*s++ != '{') goto EXPAND_FAILED_CURLY;
+        if (*s++ != '{')
+         {
+         expand_string_message = US"missing '{' for second arg of reduce";
+         goto EXPAND_FAILED_CURLY;
+         }

         t = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
         if (!t) goto EXPAND_FAILED;
         lookup_value = t;
         t = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
         if (!t) goto EXPAND_FAILED;
         lookup_value = t;

-        if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+        if (*s++ != '}')
+         {
+         expand_string_message = US"missing '}' closing second arg of reduce";
+         goto EXPAND_FAILED_CURLY;
+         }

         }
 
       while (isspace(*s)) s++;
         }
 
       while (isspace(*s)) s++;

-      if (*s++ != '{') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '{')
+        {
+       expand_string_message =
+         string_sprintf("missing '{' for last arg of %s", name);
+       goto EXPAND_FAILED_CURLY;
+       }

 
       expr = s;
 
 
       expr = s;
 


@@ -5649,11 +5806,12 @@ while (*s != 0)
       processing for real, we perform the iteration. */
 
       if (skipping) continue;
       processing for real, we perform the iteration. */
 
       if (skipping) continue;

-      while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
+      while ((iterate_item = string_nextinlist(&list, &sep, NULL, 0)))

         {
         *outsep = (uschar)sep;      /* Separator as a string */
 
         {
         *outsep = (uschar)sep;      /* Separator as a string */
 

-        DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, iterate_item);
+       DEBUG(D_expand) debug_printf_indent("%s: $item = '%s'  $value = '%s'\n",
+                         name, iterate_item, lookup_value);

 
         if (item_type == EITEM_FILTER)
           {
 
         if (item_type == EITEM_FILTER)
           {


@@ -5666,7 +5824,7 @@ while (*s != 0)
               expand_string_message, name);
             goto EXPAND_FAILED;
             }
               expand_string_message, name);
             goto EXPAND_FAILED;
             }

-          DEBUG(D_expand) debug_printf("%s: condition is %s\n", name,
+          DEBUG(D_expand) debug_printf_indent("%s: condition is %s\n", name,

             condresult? "true":"false");
           if (condresult)
             temp = iterate_item;    /* TRUE => include this item */
             condresult? "true":"false");
           if (condresult)
             temp = iterate_item;    /* TRUE => include this item */


@@ -5701,8 +5859,8 @@ while (*s != 0)
         item of the output list, add in a space if the new item begins with the
         separator character, or is an empty string. */
 
         item of the output list, add in a space if the new item begins with the
         separator character, or is an empty string. */
 

-        if (ptr != save_ptr && (temp[0] == *outsep || temp[0] == 0))
-          yield = string_cat(yield, &size, &ptr, US" ", 1);
+        if (yield->ptr != save_ptr && (temp[0] == *outsep || temp[0] == 0))
+          yield = string_catn(yield, US" ", 1);

 
         /* Add the string in "temp" to the output list that we are building,
         This is done in chunks by searching for the separator character. */
 
         /* Add the string in "temp" to the output list that we are building,
         This is done in chunks by searching for the separator character. */


@@ -5710,21 +5868,22 @@ while (*s != 0)
         for (;;)
           {
           size_t seglen = Ustrcspn(temp, outsep);
         for (;;)
           {
           size_t seglen = Ustrcspn(temp, outsep);

-            yield = string_cat(yield, &size, &ptr, temp, seglen + 1);
+
+         yield = string_catn(yield, temp, seglen + 1);

 
           /* If we got to the end of the string we output one character
           too many; backup and end the loop. Otherwise arrange to double the
           separator. */
 
 
           /* If we got to the end of the string we output one character
           too many; backup and end the loop. Otherwise arrange to double the
           separator. */
 

-          if (temp[seglen] == '\0') { ptr--; break; }
-          yield = string_cat(yield, &size, &ptr, outsep, 1);
+          if (temp[seglen] == '\0') { yield->ptr--; break; }
+          yield = string_catn(yield, outsep, 1);

           temp += seglen + 1;
           }
 
         /* Output a separator after the string: we will remove the redundant
         final one at the end. */
 
           temp += seglen + 1;
           }
 
         /* Output a separator after the string: we will remove the redundant
         final one at the end. */
 

-        yield = string_cat(yield, &size, &ptr, outsep, 1);
+        yield = string_catn(yield, outsep, 1);

         }   /* End of iteration over the list loop */
 
       /* REDUCE has generated no output above: output the final value of
         }   /* End of iteration over the list loop */
 
       /* REDUCE has generated no output above: output the final value of


@@ -5732,8 +5891,7 @@ while (*s != 0)
 
       if (item_type == EITEM_REDUCE)
         {
 
       if (item_type == EITEM_REDUCE)
         {

-        yield = string_cat(yield, &size, &ptr, lookup_value,
-          Ustrlen(lookup_value));
+        yield = string_cat(yield, lookup_value);

         lookup_value = save_lookup_value;  /* Restore $value */
         }
 
         lookup_value = save_lookup_value;  /* Restore $value */
         }
 


@@ -5741,7 +5899,7 @@ while (*s != 0)
       the redundant final separator. Even though an empty item at the end of a
       list does not count, this is tidier. */
 
       the redundant final separator. Even though an empty item at the end of a
       list does not count, this is tidier. */
 

-      else if (ptr != save_ptr) ptr--;
+      else if (yield->ptr != save_ptr) yield->ptr--;

 
       /* Restore preserved $item */
 
 
       /* Restore preserved $item */
 


@@ -5759,28 +5917,52 @@ while (*s != 0)
       uschar *save_iterate_item = iterate_item;
 
       while (isspace(*s)) s++;
       uschar *save_iterate_item = iterate_item;
 
       while (isspace(*s)) s++;

-      if (*s++ != '{') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '{')
+        {
+        expand_string_message = US"missing '{' for list arg of sort";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       srclist = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
       if (!srclist) goto EXPAND_FAILED;
 
       srclist = expand_string_internal(s, TRUE, &s, skipping, TRUE, &resetok);
       if (!srclist) goto EXPAND_FAILED;

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+        expand_string_message = US"missing '}' closing list arg of sort";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       while (isspace(*s)) s++;
 
       while (isspace(*s)) s++;

-      if (*s++ != '{') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '{')
+        {
+        expand_string_message = US"missing '{' for comparator arg of sort";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       cmp = expand_string_internal(s, TRUE, &s, skipping, FALSE, &resetok);
       if (!cmp) goto EXPAND_FAILED;
 
       cmp = expand_string_internal(s, TRUE, &s, skipping, FALSE, &resetok);
       if (!cmp) goto EXPAND_FAILED;

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+        expand_string_message = US"missing '}' closing comparator arg of sort";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       while (isspace(*s)) s++;
 
       while (isspace(*s)) s++;

-      if (*s++ != '{') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '{')
+        {
+        expand_string_message = US"missing '{' for extractor arg of sort";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       xtract = s;
       tmp = expand_string_internal(s, TRUE, &s, TRUE, TRUE, &resetok);
       if (!tmp) goto EXPAND_FAILED;
       xtract = string_copyn(xtract, s - xtract);
 
 
       xtract = s;
       tmp = expand_string_internal(s, TRUE, &s, TRUE, TRUE, &resetok);
       if (!tmp) goto EXPAND_FAILED;
       xtract = string_copyn(xtract, s - xtract);
 

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+        expand_string_message = US"missing '}' closing extractor arg of sort";
+       goto EXPAND_FAILED_CURLY;
+       }

                                                        /*{*/
       if (*s++ != '}')
         {                                              /*{*/
                                                        /*{*/
       if (*s++ != '}')
         {                                              /*{*/


@@ -5793,11 +5975,11 @@ while (*s != 0)
       while ((srcitem = string_nextinlist(&srclist, &sep, NULL, 0)))
         {
        uschar * dstitem;
       while ((srcitem = string_nextinlist(&srclist, &sep, NULL, 0)))
         {
        uschar * dstitem;

-       uschar * newlist = NULL;
-       uschar * newkeylist = NULL;
+       gstring * newlist = NULL;
+       gstring * newkeylist = NULL;

        uschar * srcfield;
 
        uschar * srcfield;
 

-        DEBUG(D_expand) debug_printf("%s: $item = \"%s\"\n", name, srcitem);
+        DEBUG(D_expand) debug_printf_indent("%s: $item = \"%s\"\n", name, srcitem);

 
        /* extract field for comparisons */
        iterate_item = srcitem;
 
        /* extract field for comparisons */
        iterate_item = srcitem;


@@ -5826,7 +6008,7 @@ while (*s != 0)
          /* build and run condition string */
          expr = string_sprintf("%s{%s}{%s}", cmp, srcfield, dstfield);
 
          /* build and run condition string */
          expr = string_sprintf("%s{%s}{%s}", cmp, srcfield, dstfield);
 

-         DEBUG(D_expand) debug_printf("%s: cond = \"%s\"\n", name, expr);
+         DEBUG(D_expand) debug_printf_indent("%s: cond = \"%s\"\n", name, expr);

          if (!eval_condition(expr, &resetok, &before))
            {
            expand_string_message = string_sprintf("comparison in sort: %s",
          if (!eval_condition(expr, &resetok, &before))
            {
            expand_string_message = string_sprintf("comparison in sort: %s",


@@ -5868,15 +6050,15 @@ while (*s != 0)
          newkeylist = string_append_listele(newkeylist, sep, srcfield);
          }
 
          newkeylist = string_append_listele(newkeylist, sep, srcfield);
          }
 

-       dstlist = newlist;
-       dstkeylist = newkeylist;
+       dstlist = newlist->s;
+       dstkeylist = newkeylist->s;

 
 

-        DEBUG(D_expand) debug_printf("%s: dstlist = \"%s\"\n", name, dstlist);
-        DEBUG(D_expand) debug_printf("%s: dstkeylist = \"%s\"\n", name, dstkeylist);
+        DEBUG(D_expand) debug_printf_indent("%s: dstlist = \"%s\"\n", name, dstlist);
+        DEBUG(D_expand) debug_printf_indent("%s: dstkeylist = \"%s\"\n", name, dstkeylist);

        }
 
       if (dstlist)
        }
 
       if (dstlist)

-       yield = string_cat(yield, &size, &ptr, dstlist, Ustrlen(dstlist));
+       yield = string_cat(yield, dstlist);

 
       /* Restore preserved $item */
       iterate_item = save_iterate_item;
 
       /* Restore preserved $item */
       iterate_item = save_iterate_item;


@@ -5974,7 +6156,7 @@ while (*s != 0)
       if(status == OK)
         {
         if (result == NULL) result = US"";
       if(status == OK)
         {
         if (result == NULL) result = US"";

-        yield = string_cat(yield, &size, &ptr, result, Ustrlen(result));
+        yield = string_cat(yield, result);

         continue;
         }
       else
         continue;
         }
       else


@@ -6000,7 +6182,11 @@ while (*s != 0)
 
       key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (!key) goto EXPAND_FAILED;                    /*{*/
 
       key = expand_string_internal(s+1, TRUE, &s, skipping, TRUE, &resetok);
       if (!key) goto EXPAND_FAILED;                    /*{*/

-      if (*s++ != '}') goto EXPAND_FAILED_CURLY;
+      if (*s++ != '}')
+        {
+        expand_string_message = US"missing '{' for name arg of env";
+       goto EXPAND_FAILED_CURLY;
+       }

 
       lookup_value = US getenv(CS key);
 
 
       lookup_value = US getenv(CS key);
 


@@ -6010,8 +6196,6 @@ while (*s != 0)
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */
                save_lookup_value,            /* value to reset for string2 */
                &s,                           /* input pointer */
                &yield,                       /* output pointer */

-               &size,                        /* output size */
-               &ptr,                         /* output current point */

                US"env",                      /* condition type */
               &resetok))
         {
                US"env",                      /* condition type */
               &resetok))
         {


@@ -6064,7 +6248,12 @@ while (*s != 0)
          sub = expand_string_internal(s+2, TRUE, &s1, skipping,
                  FALSE, &resetok);
          if (!sub)       goto EXPAND_FAILED;           /*{*/
          sub = expand_string_internal(s+2, TRUE, &s1, skipping,
                  FALSE, &resetok);
          if (!sub)       goto EXPAND_FAILED;           /*{*/

-         if (*s1 != '}') goto EXPAND_FAILED_CURLY;
+         if (*s1 != '}')
+           {
+           expand_string_message =
+             string_sprintf("missing '}' closing cert arg of %s", name);
+           goto EXPAND_FAILED_CURLY;
+           }

          if ((vp = find_var_ent(sub)) && vp->type == vtype_cert)
            {
            s = s1+1;
          if ((vp = find_var_ent(sub)) && vp->type == vtype_cert)
            {
            s = s1+1;


@@ -6093,6 +6282,46 @@ while (*s != 0)
 
     switch(c)
       {
 
     switch(c)
       {

+      case EOP_BASE32:
+       {
+        uschar *t;
+        unsigned long int n = Ustrtoul(sub, &t, 10);
+       gstring * g = NULL;
+
+        if (*t != 0)
+          {
+          expand_string_message = string_sprintf("argument for base32 "
+            "operator is \"%s\", which is not a decimal number", sub);
+          goto EXPAND_FAILED;
+          }
+       for ( ; n; n >>= 5)
+         g = string_catn(g, &base32_chars[n & 0x1f], 1);
+
+       if (g) while (g->ptr > 0) yield = string_catn(yield, &g->s[--g->ptr], 1);
+       continue;
+       }
+
+      case EOP_BASE32D:
+        {
+        uschar *tt = sub;
+        unsigned long int n = 0;
+       uschar * s;
+        while (*tt)
+          {
+          uschar * t = Ustrchr(base32_chars, *tt++);
+          if (t == NULL)
+            {
+            expand_string_message = string_sprintf("argument for base32d "
+              "operator is \"%s\", which is not a base 32 number", sub);
+            goto EXPAND_FAILED;
+            }
+          n = n * 32 + (t - base32_chars);
+          }
+        s = string_sprintf("%ld", n);
+        yield = string_cat(yield, s);
+        continue;
+        }
+

       case EOP_BASE62:
         {
         uschar *t;
       case EOP_BASE62:
         {
         uschar *t;


@@ -6104,7 +6333,7 @@ while (*s != 0)
           goto EXPAND_FAILED;
           }
         t = string_base62(n);
           goto EXPAND_FAILED;
           }
         t = string_base62(n);

-        yield = string_cat(yield, &size, &ptr, t, Ustrlen(t));
+        yield = string_cat(yield, t);

         continue;
         }
 
         continue;
         }
 


@@ -6128,7 +6357,7 @@ while (*s != 0)
           n = n * BASE_62 + (t - base62_chars);
           }
         (void)sprintf(CS buf, "%ld", n);
           n = n * BASE_62 + (t - base62_chars);
           }
         (void)sprintf(CS buf, "%ld", n);

-        yield = string_cat(yield, &size, &ptr, buf, Ustrlen(buf));
+        yield = string_cat(yield, buf);

         continue;
         }
 
         continue;
         }
 


@@ -6142,7 +6371,7 @@ while (*s != 0)
               expand_string_message);
           goto EXPAND_FAILED;
           }
               expand_string_message);
           goto EXPAND_FAILED;
           }

-        yield = string_cat(yield, &size, &ptr, expanded, Ustrlen(expanded));
+        yield = string_cat(yield, expanded);

         continue;
         }
 
         continue;
         }
 


@@ -6151,7 +6380,7 @@ while (*s != 0)
         int count = 0;
         uschar *t = sub - 1;
         while (*(++t) != 0) { *t = tolower(*t); count++; }
         int count = 0;
         uschar *t = sub - 1;
         while (*(++t) != 0) { *t = tolower(*t); count++; }

-        yield = string_cat(yield, &size, &ptr, sub, count);
+        yield = string_catn(yield, sub, count);

         continue;
         }
 
         continue;
         }
 


@@ -6160,7 +6389,7 @@ while (*s != 0)
         int count = 0;
         uschar *t = sub - 1;
         while (*(++t) != 0) { *t = toupper(*t); count++; }
         int count = 0;
         uschar *t = sub - 1;
         while (*(++t) != 0) { *t = toupper(*t); count++; }

-        yield = string_cat(yield, &size, &ptr, sub, count);
+        yield = string_catn(yield, sub, count);

         continue;
         }
 
         continue;
         }
 


@@ -6169,7 +6398,7 @@ while (*s != 0)
        if (vp && *(void **)vp->value)
          {
          uschar * cp = tls_cert_fprt_md5(*(void **)vp->value);
        if (vp && *(void **)vp->value)
          {
          uschar * cp = tls_cert_fprt_md5(*(void **)vp->value);

-         yield = string_cat(yield, &size, &ptr, cp, Ustrlen(cp));
+         yield = string_cat(yield, cp);

          }
        else
 #endif
          }
        else
 #endif


@@ -6181,7 +6410,7 @@ while (*s != 0)
          md5_start(&base);
          md5_end(&base, sub, Ustrlen(sub), digest);
          for(j = 0; j < 16; j++) sprintf(st+2*j, "%02x", digest[j]);
          md5_start(&base);
          md5_end(&base, sub, Ustrlen(sub), digest);
          for(j = 0; j < 16; j++) sprintf(st+2*j, "%02x", digest[j]);

-         yield = string_cat(yield, &size, &ptr, US st, (int)strlen(st));
+         yield = string_cat(yield, US st);

          }
         continue;
 
          }
         continue;
 


@@ -6190,34 +6419,86 @@ while (*s != 0)
        if (vp && *(void **)vp->value)
          {
          uschar * cp = tls_cert_fprt_sha1(*(void **)vp->value);
        if (vp && *(void **)vp->value)
          {
          uschar * cp = tls_cert_fprt_sha1(*(void **)vp->value);

-         yield = string_cat(yield, &size, &ptr, cp, Ustrlen(cp));
+         yield = string_cat(yield, cp);

          }
        else
 #endif
          {
          }
        else
 #endif
          {

-         sha1 base;
+         hctx h;

          uschar digest[20];
          int j;
          char st[41];
          uschar digest[20];
          int j;
          char st[41];

-         sha1_start(&base);
-         sha1_end(&base, sub, Ustrlen(sub), digest);
+         sha1_start(&h);
+         sha1_end(&h, sub, Ustrlen(sub), digest);

          for(j = 0; j < 20; j++) sprintf(st+2*j, "%02X", digest[j]);
          for(j = 0; j < 20; j++) sprintf(st+2*j, "%02X", digest[j]);

-         yield = string_cat(yield, &size, &ptr, US st, (int)strlen(st));
+         yield = string_catn(yield, US st, 40);

          }
         continue;
 
       case EOP_SHA256:
          }
         continue;
 
       case EOP_SHA256:

-#ifdef SUPPORT_TLS
+#ifdef EXIM_HAVE_SHA2

        if (vp && *(void **)vp->value)
          {
          uschar * cp = tls_cert_fprt_sha256(*(void **)vp->value);
        if (vp && *(void **)vp->value)
          {
          uschar * cp = tls_cert_fprt_sha256(*(void **)vp->value);

-         yield = string_cat(yield, &size, &ptr, cp, (int)Ustrlen(cp));
+         yield = string_cat(yield, cp);

          }
        else
          }
        else

+         {
+         hctx h;
+         blob b;
+         char st[3];
+
+         if (!exim_sha_init(&h, HASH_SHA2_256))
+           {
+           expand_string_message = US"unrecognised sha256 variant";
+           goto EXPAND_FAILED;
+           }
+         exim_sha_update(&h, sub, Ustrlen(sub));
+         exim_sha_finish(&h, &b);
+         while (b.len-- > 0)
+           {
+           sprintf(st, "%02X", *b.data++);
+           yield = string_catn(yield, US st, 2);
+           }
+         }
+#else
+         expand_string_message = US"sha256 only supported with TLS";

 #endif
 #endif

-         expand_string_message = US"sha256 only supported for certificates";

         continue;
 
         continue;
 

+      case EOP_SHA3:
+#ifdef EXIM_HAVE_SHA3
+       {
+       hctx h;
+       blob b;
+       char st[3];
+       hashmethod m = !arg ? HASH_SHA3_256
+         : Ustrcmp(arg, "224") == 0 ? HASH_SHA3_224
+         : Ustrcmp(arg, "256") == 0 ? HASH_SHA3_256
+         : Ustrcmp(arg, "384") == 0 ? HASH_SHA3_384
+         : Ustrcmp(arg, "512") == 0 ? HASH_SHA3_512
+         : HASH_BADTYPE;
+
+       if (m == HASH_BADTYPE || !exim_sha_init(&h, m))
+         {
+         expand_string_message = US"unrecognised sha3 variant";
+         goto EXPAND_FAILED;
+         }
+
+       exim_sha_update(&h, sub, Ustrlen(sub));
+       exim_sha_finish(&h, &b);
+       while (b.len-- > 0)
+         {
+         sprintf(st, "%02X", *b.data++);
+         yield = string_catn(yield, US st, 2);
+         }
+       }
+        continue;
+#else
+       expand_string_message = US"sha3 only supported with GnuTLS 3.5.0 +";
+       goto EXPAND_FAILED;
+#endif
+

       /* Convert hex encoding to base64 encoding */
 
       case EOP_HEX2B64:
       /* Convert hex encoding to base64 encoding */
 
       case EOP_HEX2B64:


@@ -6262,7 +6543,7 @@ while (*s != 0)
           }
 
         enc = b64encode(sub, out - sub);
           }
 
         enc = b64encode(sub, out - sub);

-        yield = string_cat(yield, &size, &ptr, enc, Ustrlen(enc));
+        yield = string_cat(yield, enc);

         continue;
         }
 
         continue;
         }
 


@@ -6274,10 +6555,9 @@ while (*s != 0)
         while (*(++t) != 0)
           {
           if (*t < 0x21 || 0x7E < *t)
         while (*(++t) != 0)
           {
           if (*t < 0x21 || 0x7E < *t)

-            yield = string_cat(yield, &size, &ptr,
-             string_sprintf("\\x%02x", *t), 4);
+            yield = string_catn(yield, string_sprintf("\\x%02x", *t), 4);

          else
          else

-           yield = string_cat(yield, &size, &ptr, t, 1);
+           yield = string_catn(yield, t, 1);

           }
        continue;
        }
           }
        continue;
        }


@@ -6293,7 +6573,7 @@ while (*s != 0)
 
        while (string_nextinlist(CUSS &sub, &sep, buffer, sizeof(buffer)) != NULL) cnt++;
        cp = string_sprintf("%d", cnt);
 
        while (string_nextinlist(CUSS &sub, &sep, buffer, sizeof(buffer)) != NULL) cnt++;
        cp = string_sprintf("%d", cnt);

-        yield = string_cat(yield, &size, &ptr, cp, Ustrlen(cp));
+        yield = string_cat(yield, cp);

         continue;
         }
 
         continue;
         }
 


@@ -6343,11 +6623,11 @@ while (*s != 0)
 
        list = ((namedlist_block *)(t->data.ptr))->string;
 
 
        list = ((namedlist_block *)(t->data.ptr))->string;
 

-       while ((item = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
+       while ((item = string_nextinlist(&list, &sep, buffer, sizeof(buffer))))

          {
          uschar * buf = US" : ";
          if (needsep)
          {
          uschar * buf = US" : ";
          if (needsep)

-           yield = string_cat(yield, &size, &ptr, buf, 3);
+           yield = string_catn(yield, buf, 3);

          else
            needsep = TRUE;
 
          else
            needsep = TRUE;
 


@@ -6361,23 +6641,23 @@ while (*s != 0)
            char * cp;
            char tok[3];
            tok[0] = sep; tok[1] = ':'; tok[2] = 0;
            char * cp;
            char tok[3];
            tok[0] = sep; tok[1] = ':'; tok[2] = 0;

-           while ((cp= strpbrk((const char *)item, tok)))
+           while ((cp= strpbrk(CCS item, tok)))

              {
              {

-              yield = string_cat(yield, &size, &ptr, item, cp-(char *)item);
+              yield = string_catn(yield, item, cp - CS item);

              if (*cp++ == ':') /* colon in a non-colon-sep list item, needs doubling */
                {
              if (*cp++ == ':') /* colon in a non-colon-sep list item, needs doubling */
                {

-                yield = string_cat(yield, &size, &ptr, US"::", 2);
-               item = (uschar *)cp;
+                yield = string_catn(yield, US"::", 2);
+               item = US cp;

                }
              else              /* sep in item; should already be doubled; emit once */
                {
                }
              else              /* sep in item; should already be doubled; emit once */
                {

-                yield = string_cat(yield, &size, &ptr, (uschar *)tok, 1);
+                yield = string_catn(yield, US tok, 1);

                if (*cp == sep) cp++;
                if (*cp == sep) cp++;

-               item = (uschar *)cp;
+               item = US cp;

                }
              }
            }
                }
              }
            }

-          yield = string_cat(yield, &size, &ptr, item, Ustrlen(item));
+          yield = string_cat(yield, item);

          }
         continue;
        }
          }
         continue;
        }


@@ -6425,7 +6705,7 @@ while (*s != 0)
 
         /* Convert to masked textual format and add to output. */
 
 
         /* Convert to masked textual format and add to output. */
 

-        yield = string_cat(yield, &size, &ptr, buffer,
+        yield = string_catn(yield, buffer,

           host_nmtoa(count, binary, mask, buffer, '.'));
         continue;
         }
           host_nmtoa(count, binary, mask, buffer, '.'));
         continue;
         }


@@ -6455,8 +6735,7 @@ while (*s != 0)
            goto EXPAND_FAILED;
          }
 
            goto EXPAND_FAILED;
          }
 

-       yield = string_cat(yield, &size, &ptr, buffer,
-                 c == EOP_IPV6NORM
+       yield = string_catn(yield, buffer, c == EOP_IPV6NORM

                    ? ipv6_nmtoa(binary, buffer)
                    : host_nmtoa(4, binary, -1, buffer, ':')
                  );
                    ? ipv6_nmtoa(binary, buffer)
                    : host_nmtoa(4, binary, -1, buffer, ':')
                  );


@@ -6467,23 +6746,21 @@ while (*s != 0)
       case EOP_LOCAL_PART:
       case EOP_DOMAIN:
         {
       case EOP_LOCAL_PART:
       case EOP_DOMAIN:
         {

-        uschar *error;
+        uschar * error;

         int start, end, domain;
         int start, end, domain;

-        uschar *t = parse_extract_address(sub, &error, &start, &end, &domain,
+        uschar * t = parse_extract_address(sub, &error, &start, &end, &domain,

           FALSE);
           FALSE);

-        if (t != NULL)
-          {
+        if (t)

           if (c != EOP_DOMAIN)
             {
             if (c == EOP_LOCAL_PART && domain != 0) end = start + domain - 1;
           if (c != EOP_DOMAIN)
             {
             if (c == EOP_LOCAL_PART && domain != 0) end = start + domain - 1;

-            yield = string_cat(yield, &size, &ptr, sub+start, end-start);
+            yield = string_catn(yield, sub+start, end-start);

             }
           else if (domain != 0)
             {
             domain += start;
             }
           else if (domain != 0)
             {
             domain += start;

-            yield = string_cat(yield, &size, &ptr, sub+domain, end-domain);
+            yield = string_catn(yield, sub+domain, end-domain);

             }
             }

-          }

         continue;
         }
 
         continue;
         }
 


@@ -6491,11 +6768,18 @@ while (*s != 0)
         {
         uschar outsep[2] = { ':', '\0' };
         uschar *address, *error;
         {
         uschar outsep[2] = { ':', '\0' };
         uschar *address, *error;

-        int save_ptr = ptr;
+        int save_ptr = yield->ptr;

         int start, end, domain;  /* Not really used */
 
         while (isspace(*sub)) sub++;
         int start, end, domain;  /* Not really used */
 
         while (isspace(*sub)) sub++;

-        if (*sub == '>') { *outsep = *++sub; ++sub; }
+        if (*sub == '>')
+          if (*outsep = *++sub) ++sub;
+          else
+           {
+            expand_string_message = string_sprintf("output separator "
+              "missing in expanding ${addresses:%s}", --sub);
+            goto EXPAND_FAILED;
+            }

         parse_allow_group = TRUE;
 
         for (;;)
         parse_allow_group = TRUE;
 
         for (;;)


@@ -6515,26 +6799,26 @@ while (*s != 0)
 
           if (address != NULL)
             {
 
           if (address != NULL)
             {

-            if (ptr != save_ptr && address[0] == *outsep)
-              yield = string_cat(yield, &size, &ptr, US" ", 1);
+            if (yield->ptr != save_ptr && address[0] == *outsep)
+              yield = string_catn(yield, US" ", 1);

 
             for (;;)
               {
               size_t seglen = Ustrcspn(address, outsep);
 
             for (;;)
               {
               size_t seglen = Ustrcspn(address, outsep);

-              yield = string_cat(yield, &size, &ptr, address, seglen + 1);
+              yield = string_catn(yield, address, seglen + 1);

 
               /* If we got to the end of the string we output one character
               too many. */
 
 
               /* If we got to the end of the string we output one character
               too many. */
 

-              if (address[seglen] == '\0') { ptr--; break; }
-              yield = string_cat(yield, &size, &ptr, outsep, 1);
+              if (address[seglen] == '\0') { yield->ptr--; break; }
+              yield = string_catn(yield, outsep, 1);

               address += seglen + 1;
               }
 
             /* Output a separator after the string: we will remove the
             redundant final one at the end. */
 
               address += seglen + 1;
               }
 
             /* Output a separator after the string: we will remove the
             redundant final one at the end. */
 

-            yield = string_cat(yield, &size, &ptr, outsep, 1);
+            yield = string_catn(yield, outsep, 1);

             }
 
           if (saveend == '\0') break;
             }
 
           if (saveend == '\0') break;


@@ -6544,7 +6828,7 @@ while (*s != 0)
         /* If we have generated anything, remove the redundant final
         separator. */
 
         /* If we have generated anything, remove the redundant final
         separator. */
 

-        if (ptr != save_ptr) ptr--;
+        if (yield->ptr != save_ptr) yield->ptr--;

         parse_allow_group = FALSE;
         continue;
         }
         parse_allow_group = FALSE;
         continue;
         }


@@ -6581,24 +6865,24 @@ while (*s != 0)
 
         if (needs_quote)
           {
 
         if (needs_quote)
           {

-          yield = string_cat(yield, &size, &ptr, US"\"", 1);
+          yield = string_catn(yield, US"\"", 1);

           t = sub - 1;
           while (*(++t) != 0)
             {
             if (*t == '\n')
           t = sub - 1;
           while (*(++t) != 0)
             {
             if (*t == '\n')

-              yield = string_cat(yield, &size, &ptr, US"\\n", 2);
+              yield = string_catn(yield, US"\\n", 2);

             else if (*t == '\r')
             else if (*t == '\r')

-              yield = string_cat(yield, &size, &ptr, US"\\r", 2);
+              yield = string_catn(yield, US"\\r", 2);

             else
               {
               if (*t == '\\' || *t == '"')
             else
               {
               if (*t == '\\' || *t == '"')

-                yield = string_cat(yield, &size, &ptr, US"\\", 1);
-              yield = string_cat(yield, &size, &ptr, t, 1);
+                yield = string_catn(yield, US"\\", 1);
+              yield = string_catn(yield, t, 1);

               }
             }
               }
             }

-          yield = string_cat(yield, &size, &ptr, US"\"", 1);
+          yield = string_catn(yield, US"\"", 1);

           }
           }

-        else yield = string_cat(yield, &size, &ptr, sub, Ustrlen(sub));
+        else yield = string_cat(yield, sub);

         continue;
         }
 
         continue;
         }
 


@@ -6630,7 +6914,7 @@ while (*s != 0)
           goto EXPAND_FAILED;
           }
 
           goto EXPAND_FAILED;
           }
 

-        yield = string_cat(yield, &size, &ptr, sub, Ustrlen(sub));
+        yield = string_cat(yield, sub);

         continue;
         }
 
         continue;
         }
 


@@ -6643,8 +6927,8 @@ while (*s != 0)
         while (*(++t) != 0)
           {
           if (!isalnum(*t))
         while (*(++t) != 0)
           {
           if (!isalnum(*t))

-            yield = string_cat(yield, &size, &ptr, US"\\", 1);
-          yield = string_cat(yield, &size, &ptr, t, 1);
+            yield = string_catn(yield, US"\\", 1);
+          yield = string_catn(yield, t, 1);

           }
         continue;
         }
           }
         continue;
         }


@@ -6657,7 +6941,7 @@ while (*s != 0)
         uschar buffer[2048];
        const uschar *string = parse_quote_2047(sub, Ustrlen(sub), headers_charset,
           buffer, sizeof(buffer), FALSE);
         uschar buffer[2048];
        const uschar *string = parse_quote_2047(sub, Ustrlen(sub), headers_charset,
           buffer, sizeof(buffer), FALSE);

-        yield = string_cat(yield, &size, &ptr, string, Ustrlen(string));
+        yield = string_cat(yield, string);

         continue;
         }
 
         continue;
         }
 


@@ -6674,7 +6958,7 @@ while (*s != 0)
           expand_string_message = error;
           goto EXPAND_FAILED;
           }
           expand_string_message = error;
           goto EXPAND_FAILED;
           }

-        yield = string_cat(yield, &size, &ptr, decoded, len);
+        yield = string_catn(yield, decoded, len);

         continue;
         }
 
         continue;
         }
 


@@ -6690,7 +6974,7 @@ while (*s != 0)
           GETUTF8INC(c, sub);
           if (c > 255) c = '_';
           buff[0] = c;
           GETUTF8INC(c, sub);
           if (c > 255) c = '_';
           buff[0] = c;

-          yield = string_cat(yield, &size, &ptr, buff, 1);
+          yield = string_catn(yield, buff, 1);

           }
         continue;
         }
           }
         continue;
         }


@@ -6725,7 +7009,7 @@ while (*s != 0)
                  complete = -1;        /* error (RFC3629 limit) */
                else
                  {             /* finished; output utf-8 sequence */
                  complete = -1;        /* error (RFC3629 limit) */
                else
                  {             /* finished; output utf-8 sequence */

-                 yield = string_cat(yield, &size, &ptr, seq_buff, seq_len);
+                 yield = string_catn(yield, seq_buff, seq_len);

                  index = 0;
                  }
              }
                  index = 0;
                  }
              }


@@ -6734,7 +7018,7 @@ while (*s != 0)
            {
            if((c & 0x80) == 0) /* 1-byte sequence, US-ASCII, keep it */
              {
            {
            if((c & 0x80) == 0) /* 1-byte sequence, US-ASCII, keep it */
              {

-             yield = string_cat(yield, &size, &ptr, &c, 1);
+             yield = string_catn(yield, &c, 1);

              continue;
              }
            if((c & 0xe0) == 0xc0)              /* 2-byte sequence */
              continue;
              }
            if((c & 0xe0) == 0xc0)              /* 2-byte sequence */


@@ -6767,11 +7051,11 @@ while (*s != 0)
          if (complete != 0)
            {
            bytes_left = index = 0;
          if (complete != 0)
            {
            bytes_left = index = 0;

-           yield = string_cat(yield, &size, &ptr, UTF8_REPLACEMENT_CHAR, 1);
+           yield = string_catn(yield, UTF8_REPLACEMENT_CHAR, 1);

            }
          if ((complete == 1) && ((c & 0x80) == 0))
                        /* ASCII character follows incomplete sequence */
            }
          if ((complete == 1) && ((c & 0x80) == 0))
                        /* ASCII character follows incomplete sequence */

-             yield = string_cat(yield, &size, &ptr, &c, 1);
+             yield = string_catn(yield, &c, 1);

          }
         continue;
         }
          }
         continue;
         }


@@ -6788,7 +7072,7 @@ while (*s != 0)
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }

-       yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+       yield = string_cat(yield, s);

         continue;
        }
 
         continue;
        }
 


@@ -6803,7 +7087,7 @@ while (*s != 0)
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }

-       yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+       yield = string_cat(yield, s);

         continue;
        }
 
         continue;
        }
 


@@ -6818,8 +7102,8 @@ while (*s != 0)
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }

-       yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
-       DEBUG(D_expand) debug_printf("yield: '%s'\n", yield);
+       yield = string_cat(yield, s);
+       DEBUG(D_expand) debug_printf_indent("yield: '%s'\n", yield->s);

         continue;
        }
 
         continue;
        }
 


@@ -6834,7 +7118,7 @@ while (*s != 0)
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }
            string_printing(sub), error);
          goto EXPAND_FAILED;
          }

-       yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+       yield = string_cat(yield, s);

         continue;
        }
 #endif /* EXPERIMENTAL_INTERNATIONAL */
         continue;
        }
 #endif /* EXPERIMENTAL_INTERNATIONAL */


@@ -6843,11 +7127,23 @@ while (*s != 0)
 
       case EOP_ESCAPE:
         {
 
       case EOP_ESCAPE:
         {

-        const uschar *t = string_printing(sub);
-        yield = string_cat(yield, &size, &ptr, t, Ustrlen(t));
+        const uschar * t = string_printing(sub);
+        yield = string_cat(yield, t);

         continue;
         }
 
         continue;
         }
 

+      case EOP_ESCAPE8BIT:
+       {
+       const uschar * s = sub;
+       uschar c;
+
+       for (s = sub; (c = *s); s++)
+         yield = c < 127 && c != '\\'
+           ? string_catn(yield, s, 1)
+           : string_catn(yield, string_sprintf("\\%03o", c), 4);
+       continue;
+       }
+

       /* Handle numeric expression evaluation */
 
       case EOP_EVAL:
       /* Handle numeric expression evaluation */
 
       case EOP_EVAL:


@@ -6859,12 +7155,12 @@ while (*s != 0)
         if (error != NULL)
           {
           expand_string_message = string_sprintf("error in expression "
         if (error != NULL)
           {
           expand_string_message = string_sprintf("error in expression "

-            "evaluation: %s (after processing \"%.*s\")", error, sub-save_sub,
-              save_sub);
+            "evaluation: %s (after processing \"%.*s\")", error,
+           (int)(sub-save_sub), save_sub);

           goto EXPAND_FAILED;
           }
         sprintf(CS var_buffer, PR_EXIM_ARITH, n);
           goto EXPAND_FAILED;
           }
         sprintf(CS var_buffer, PR_EXIM_ARITH, n);

-        yield = string_cat(yield, &size, &ptr, var_buffer, Ustrlen(var_buffer));
+        yield = string_cat(yield, var_buffer);

         continue;
         }
 
         continue;
         }
 


@@ -6880,7 +7176,7 @@ while (*s != 0)
           goto EXPAND_FAILED;
           }
         sprintf(CS var_buffer, "%d", n);
           goto EXPAND_FAILED;
           }
         sprintf(CS var_buffer, "%d", n);

-        yield = string_cat(yield, &size, &ptr, var_buffer, Ustrlen(var_buffer));
+        yield = string_cat(yield, var_buffer);

         continue;
         }
 
         continue;
         }
 


@@ -6895,7 +7191,7 @@ while (*s != 0)
           goto EXPAND_FAILED;
           }
         t = readconf_printtime(n);
           goto EXPAND_FAILED;
           }
         t = readconf_printtime(n);

-        yield = string_cat(yield, &size, &ptr, t, Ustrlen(t));
+        yield = string_cat(yield, t);

         continue;
         }
 
         continue;
         }
 


@@ -6911,7 +7207,7 @@ while (*s != 0)
 #else
        uschar * s = b64encode(sub, Ustrlen(sub));
 #endif
 #else
        uschar * s = b64encode(sub, Ustrlen(sub));
 #endif

-       yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+       yield = string_cat(yield, s);

        continue;
        }
 
        continue;
        }
 


@@ -6925,7 +7221,7 @@ while (*s != 0)
             "well-formed for \"%s\" operator", sub, name);
           goto EXPAND_FAILED;
           }
             "well-formed for \"%s\" operator", sub, name);
           goto EXPAND_FAILED;
           }

-        yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+        yield = string_cat(yield, s);

         continue;
         }
 
         continue;
         }
 


@@ -6935,7 +7231,7 @@ while (*s != 0)
         {
         uschar buff[24];
         (void)sprintf(CS buff, "%d", Ustrlen(sub));
         {
         uschar buff[24];
         (void)sprintf(CS buff, "%d", Ustrlen(sub));

-        yield = string_cat(yield, &size, &ptr, buff, Ustrlen(buff));
+        yield = string_cat(yield, buff);

         continue;
         }
 
         continue;
         }
 


@@ -7026,7 +7322,7 @@ while (*s != 0)
              extract_substr(sub, value1, value2, &len);
 
         if (ret == NULL) goto EXPAND_FAILED;
              extract_substr(sub, value1, value2, &len);
 
         if (ret == NULL) goto EXPAND_FAILED;

-        yield = string_cat(yield, &size, &ptr, ret, len);
+        yield = string_catn(yield, ret, len);

         continue;
         }
 
         continue;
         }
 


@@ -7081,7 +7377,7 @@ while (*s != 0)
           (long)st.st_dev, (long)st.st_nlink, (long)st.st_uid,
           (long)st.st_gid, st.st_size, (long)st.st_atime,
           (long)st.st_mtime, (long)st.st_ctime);
           (long)st.st_dev, (long)st.st_nlink, (long)st.st_uid,
           (long)st.st_gid, st.st_size, (long)st.st_atime,
           (long)st.st_mtime, (long)st.st_ctime);

-        yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+        yield = string_cat(yield, s);

         continue;
         }
 
         continue;
         }
 


@@ -7096,7 +7392,7 @@ while (*s != 0)
         if (expand_string_message != NULL)
           goto EXPAND_FAILED;
         s = string_sprintf("%d", vaguely_random_number((int)max));
         if (expand_string_message != NULL)
           goto EXPAND_FAILED;
         s = string_sprintf("%d", vaguely_random_number((int)max));

-        yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+        yield = string_cat(yield, s);

         continue;
         }
 
         continue;
         }
 


@@ -7115,7 +7411,7 @@ while (*s != 0)
           goto EXPAND_FAILED;
           }
         invert_address(reversed, sub);
           goto EXPAND_FAILED;
           }
         invert_address(reversed, sub);

-        yield = string_cat(yield, &size, &ptr, reversed, Ustrlen(reversed));
+        yield = string_cat(yield, reversed);

         continue;
         }
 
         continue;
         }
 


@@ -7139,14 +7435,17 @@ while (*s != 0)
     {
     int len;
     int newsize = 0;
     {
     int len;
     int newsize = 0;

-    if (ptr == 0)
+    gstring * g = NULL;
+
+    if (!yield)
+      g = store_get(sizeof(gstring));
+    else if (yield->ptr == 0)

       {
       if (resetok) store_reset(yield);
       yield = NULL;
       {
       if (resetok) store_reset(yield);
       yield = NULL;

-      size = 0;
+      g = store_get(sizeof(gstring));  /* alloc _before_ calling find_variable() */

       }
       }

-    value = find_variable(name, FALSE, skipping, &newsize);
-    if (value == NULL)
+    if (!(value = find_variable(name, FALSE, skipping, &newsize)))

       {
       expand_string_message =
         string_sprintf("unknown variable in \"${%s}\"", name);
       {
       expand_string_message =
         string_sprintf("unknown variable in \"${%s}\"", name);


@@ -7154,13 +7453,15 @@ while (*s != 0)
       goto EXPAND_FAILED;
       }
     len = Ustrlen(value);
       goto EXPAND_FAILED;
       }
     len = Ustrlen(value);

-    if (yield == NULL && newsize != 0)
+    if (!yield && newsize)

       {
       {

-      yield = value;
-      size = newsize;
-      ptr = len;
+      yield = g;
+      yield->size = newsize;
+      yield->ptr = len;
+      yield->s = value;

       }
       }

-    else yield = string_cat(yield, &size, &ptr, value, len);
+    else
+      yield = string_catn(yield, value, len);

     continue;
     }
 
     continue;
     }
 


@@ -7188,47 +7489,65 @@ if (ket_ends && *s == 0)
 added to the string. If so, set up an empty string. Add a terminating zero. If
 left != NULL, return a pointer to the terminator. */
 
 added to the string. If so, set up an empty string. Add a terminating zero. If
 left != NULL, return a pointer to the terminator. */
 

-if (yield == NULL) yield = store_get(1);
-yield[ptr] = 0;
-if (left != NULL) *left = s;
+if (!yield)
+  yield = string_get(1);
+(void) string_from_gstring(yield);
+if (left) *left = s;

 
 /* Any stacking store that was used above the final string is no longer needed.
 In many cases the final string will be the first one that was got and so there
 will be optimal store usage. */
 
 
 /* Any stacking store that was used above the final string is no longer needed.
 In many cases the final string will be the first one that was got and so there
 will be optimal store usage. */
 

-if (resetok) store_reset(yield + ptr + 1);
+if (resetok) store_reset(yield->s + (yield->size = yield->ptr + 1));

 else if (resetok_p) *resetok_p = FALSE;
 
 DEBUG(D_expand)
   {
 else if (resetok_p) *resetok_p = FALSE;
 
 DEBUG(D_expand)
   {

-  debug_printf("expanding: %.*s\n   result: %s\n", (int)(s - string), string,
-    yield);
-  if (skipping) debug_printf("skipping: result is not used\n");
+  debug_printf_indent(UTF8_VERT_RIGHT UTF8_HORIZ UTF8_HORIZ
+    "expanding: %.*s\n",
+    (int)(s - string), string);
+  debug_printf_indent("%s"
+    UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
+    "result: %s\n",
+    skipping ? UTF8_VERT_RIGHT : UTF8_UP_RIGHT,
+    yield->s);
+  if (skipping)
+    debug_printf_indent(UTF8_UP_RIGHT UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
+      "skipping: result is not used\n");

   }
   }

-return yield;
+expand_level--;
+return yield->s;

 
 /* This is the failure exit: easiest to program with a goto. We still need
 to update the pointer to the terminator, for cases of nested calls with "fail".
 */
 
 EXPAND_FAILED_CURLY:
 
 /* This is the failure exit: easiest to program with a goto. We still need
 to update the pointer to the terminator, for cases of nested calls with "fail".
 */
 
 EXPAND_FAILED_CURLY:

-expand_string_message = malformed_header?
-  US"missing or misplaced { or } - could be header name not terminated by colon"
-  :
-  US"missing or misplaced { or }";
+if (malformed_header)
+  expand_string_message =
+    US"missing or misplaced { or } - could be header name not terminated by colon";
+
+else if (!expand_string_message || !*expand_string_message)
+  expand_string_message = US"missing or misplaced { or }";

 
 /* At one point, Exim reset the store to yield (if yield was not NULL), but
 that is a bad idea, because expand_string_message is in dynamic store. */
 
 EXPAND_FAILED:
 
 /* At one point, Exim reset the store to yield (if yield was not NULL), but
 that is a bad idea, because expand_string_message is in dynamic store. */
 
 EXPAND_FAILED:

-if (left != NULL) *left = s;
+if (left) *left = s;

 DEBUG(D_expand)
   {
 DEBUG(D_expand)
   {

-  debug_printf("failed to expand: %s\n", string);
-  debug_printf("   error message: %s\n", expand_string_message);
-  if (expand_string_forcedfail) debug_printf("failure was forced\n");
+  debug_printf_indent(UTF8_VERT_RIGHT "failed to expand: %s\n",
+    string);
+  debug_printf_indent("%s" UTF8_HORIZ UTF8_HORIZ UTF8_HORIZ
+    "error message: %s\n",
+    expand_string_forcedfail ? UTF8_VERT_RIGHT : UTF8_UP_RIGHT,
+    expand_string_message);
+  if (expand_string_forcedfail)
+    debug_printf_indent(UTF8_UP_RIGHT "failure was forced\n");

   }
 if (resetok_p) *resetok_p = resetok;
   }
 if (resetok_p) *resetok_p = resetok;

+expand_level--;

 return NULL;
 }
 
 return NULL;
 }
 


@@ -7355,7 +7674,7 @@ if (isspace(*s))
   if (*s == '\0')
     {
       DEBUG(D_expand)
   if (*s == '\0')
     {
       DEBUG(D_expand)

-       debug_printf("treating blank string as number 0\n");
+       debug_printf_indent("treating blank string as number 0\n");

       return 0;
     }
   }
       return 0;
     }
   }


@@ -7466,6 +7785,83 @@ return OK;
 
 
 
 
 
 

+/* Avoid potentially exposing a password in a string about to be logged */
+
+uschar *
+expand_hide_passwords(uschar * s)
+{
+return (  (  Ustrstr(s, "failed to expand") != NULL
+         || Ustrstr(s, "expansion of ")    != NULL
+         ) 
+       && (  Ustrstr(s, "mysql")   != NULL
+         || Ustrstr(s, "pgsql")   != NULL
+         || Ustrstr(s, "redis")   != NULL
+         || Ustrstr(s, "sqlite")  != NULL
+         || Ustrstr(s, "ldap:")   != NULL
+         || Ustrstr(s, "ldaps:")  != NULL
+         || Ustrstr(s, "ldapi:")  != NULL
+         || Ustrstr(s, "ldapdn:") != NULL
+         || Ustrstr(s, "ldapm:")  != NULL
+       )  ) 
+  ? US"Temporary internal error" : s;
+}
+
+
+
+/*************************************************
+* Error-checking for testsuite                   *
+*************************************************/
+typedef struct {
+  const char * filename;
+  int          linenumber;
+  uschar *     region_start;
+  uschar *     region_end;
+  const uschar *var_name;
+  const uschar *var_data;
+} err_ctx;
+
+static void
+assert_variable_notin(uschar * var_name, uschar * var_data, void * ctx)
+{
+err_ctx * e = ctx;
+if (var_data >= e->region_start  &&  var_data < e->region_end)
+  {
+  e->var_name = CUS var_name;
+  e->var_data = CUS var_data;
+  }
+}
+
+void
+assert_no_variables(void * ptr, int len, const char * filename, int linenumber)
+{
+err_ctx e = {filename, linenumber, ptr, US ptr + len, NULL };
+int i;
+var_entry * v;
+
+/* check acl_ variables */
+tree_walk(acl_var_c, assert_variable_notin, &e);
+tree_walk(acl_var_m, assert_variable_notin, &e);
+
+/* check auth<n> variables */
+for (i = 0; i < AUTH_VARS; i++) if (auth_vars[i])
+  assert_variable_notin(US"auth<n>", auth_vars[i], &e);
+
+/* check regex<n> variables */
+for (i = 0; i < REGEX_VARS; i++) if (regex_vars[i])
+  assert_variable_notin(US"regex<n>", regex_vars[i], &e);
+
+/* check known-name variables */
+for (v = var_table; v < var_table + var_table_size; v++)
+  if (v->type == vtype_stringptr)
+    assert_variable_notin(US v->name, *(USS v->value), &e);
+
+if (e.var_name)
+  log_write(0, LOG_MAIN|LOG_PANIC_DIE,
+    "live variable '%s' destroyed by reset_store at %s:%d\n- value '%.64s'",
+    e.var_name, e.filename, e.linenumber, e.var_data);
+}
+
+

 
 /*************************************************
 **************************************************
 
 /*************************************************
 **************************************************