src/src/lookups/lf_sqlperform.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   6 /* Copyright (c) The Exim Maintainers 2020 */
   7 /* See the file NOTICE for conditions of use and distribution. */
   8
   9
  10 #include "../exim.h"
  11 #include "lf_functions.h"
  12
  13
  14
  15 /*************************************************
  16 *    Call SQL server(s) to run an actual query   *
  17 *************************************************/
  18
  19 /* All the SQL lookups are of the same form, with a list of servers to try
  20 until one can be accessed. It is now also possible to provide the server data
  21 as part of the query. This function manages server selection and looping; each
  22 lookup has its own function for actually performing the lookup.
  23
  24 Arguments:
  25   name           the lookup name, e.g. "MySQL"
  26   optionname     the name of the servers option, e.g. "mysql_servers"
  27   optserverlist  the value of the servers option
  28   query          the query
  29   result         where to pass back the result
  30   errmsg         where to pass back an error message
  31   do_cache       to be set zero if data is changed
  32   func           the lookup function to call
  33
  34 Returns:         the return from the lookup function, or DEFER
  35 */
  36
  37 int
  38 lf_sqlperform(const uschar *name, const uschar *optionname,
  39   const uschar *optserverlist, const uschar *query,
  40   uschar **result, uschar **errmsg, uint *do_cache, const uschar * opts,
  41   int(*fn)(const uschar *, uschar *, uschar **, uschar **, BOOL *, uint *, const uschar *))
  42 {
  43 int rc;
  44 uschar *server;
  45 BOOL defer_break = FALSE;
  46
  47 DEBUG(D_lookup) debug_printf_indent("%s query: \"%s\" opts '%s'\n", name, query, opts);
  48
  49 /* Handle queries that do have server information at the start. */
  50
  51 if (Ustrncmp(query, "servers", 7) == 0)
  52   {
  53   int qsep = 0;
  54   const uschar *s, *ss;
  55   const uschar *qserverlist;
  56   uschar *qserver;
  57
  58   s = query + 7;
  59   skip_whitespace(&s);
  60   if (*s++ != '=')
  61     {
  62     *errmsg = string_sprintf("missing = after \"servers\" in %s lookup", name);
  63     return DEFER;
  64     }
  65   skip_whitespace(&s);
  66
  67   ss = Ustrchr(s, ';');
  68   if (!ss)
  69     {
  70     *errmsg = string_sprintf("missing ; after \"servers=\" in %s lookup",
  71       name);
  72     return DEFER;
  73     }
  74
  75   if (ss == s)
  76     {
  77     *errmsg = string_sprintf("\"servers=\" defines no servers in \"%s\"",
  78       query);
  79     return DEFER;
  80     }
  81
  82   qserverlist = string_sprintf("%.*s", (int)(ss - s), s);
  83
  84   while ((qserver = string_nextinlist(&qserverlist, &qsep, NULL, 0)))
  85     {
  86     if (Ustrchr(qserver, '/'))
  87       server = qserver;
  88     else
  89       {
  90       int len = Ustrlen(qserver);
  91       const uschar * serverlist = optserverlist;
  92
  93       for (int sep = 0; server = string_nextinlist(&serverlist, &sep, NULL, 0);)
  94         if (Ustrncmp(server, qserver, len) == 0 && server[len] == '/')
  95           break;
  96
  97       if (!server)
  98         {
  99         *errmsg = string_sprintf("%s server \"%s\" not found in %s", name,
 100           qserver, optionname);
 101         return DEFER;
 102         }
 103       }
 104
 105     if (is_tainted(server))
 106       {
 107       *errmsg = string_sprintf("%s server \"%s\" is tainted", name, server);
 108       return DEFER;
 109       }
 110
 111     rc = (*fn)(ss+1, server, result, errmsg, &defer_break, do_cache, opts);
 112     if (rc != DEFER || defer_break) return rc;
 113     }
 114   }
 115
 116 /* Handle queries that do not have server information at the start. */
 117
 118 else
 119   {
 120   const uschar * serverlist = NULL;
 121
 122   /* If options are present, scan for a server definition.  Default to
 123   the "optserverlist" srgument. */
 124
 125   if (opts)
 126     {
 127     uschar * ele;
 128     for (int sep = ','; ele = string_nextinlist(&opts, &sep, NULL, 0); )
 129       if (Ustrncmp(ele, "servers=", 8) == 0)
 130         { serverlist = ele + 8; break; }
 131     }
 132
 133   if (!serverlist)
 134     serverlist = optserverlist;
 135   if (!serverlist)
 136     *errmsg = string_sprintf("no %s servers defined (%s option)", name,
 137       optionname);
 138   else
 139     for (int d = 0; (server = string_nextinlist(&serverlist, &d, NULL, 0)); )
 140       {
 141       /* If not a full spec assume from options; scan main list for matching
 142       hostname */
 143
 144       if (!Ustrchr(server, '/'))
 145         {
 146         int len = Ustrlen(server);
 147         const uschar * slist = optserverlist;
 148         uschar * ele;
 149         for (int sep = 0; ele = string_nextinlist(&slist, &sep, NULL, 0); )
 150           if (Ustrncmp(ele, server, len) == 0 && ele[len] == '/')
 151             break;
 152         if (!ele)
 153           {
 154           *errmsg = string_sprintf("%s server \"%s\" not found in %s", name,
 155             server, optionname);
 156           return DEFER;
 157           }
 158         server = ele;
 159         }
 160
 161       if (is_tainted(server))
 162         {
 163         *errmsg = string_sprintf("%s server \"%s\" is tainted", name, server);
 164         return DEFER;
 165         }
 166
 167       rc = (*fn)(query, server, result, errmsg, &defer_break, do_cache, opts);
 168       if (rc != DEFER || defer_break) return rc;
 169       }
 170   }
 171
 172 return DEFER;
 173 }
 174
 175 /* End of lf_sqlperform.c */