src/src/lookups/nisplus.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 #include "../exim.h"
   9 #include "lf_functions.h"
  10
  11 #include <rpcsvc/nis.h>
  12
  13
  14 /*************************************************
  15 *              Open entry point                  *
  16 *************************************************/
  17
  18 /* See local README for interface description. */
  19
  20 static void *
  21 nisplus_open(uschar *filename, uschar **errmsg)
  22 {
  23 return (void *)(1);    /* Just return something non-null */
  24 }
  25
  26
  27
  28 /*************************************************
  29 *               Find entry point                 *
  30 *************************************************/
  31
  32 /* See local README for interface description. The format of queries for a
  33 NIS+ search is
  34
  35   [field=value,...],table-name
  36 or
  37   [field=value,...],table-name:result-field-name
  38
  39 in other words, a normal NIS+ "indexed name", with an optional result field
  40 name tagged on the end after a colon. If there is no result-field name, the
  41 yield is the concatenation of all the fields, preceded by their names and an
  42 equals sign. */
  43
  44 static int
  45 nisplus_find(void *handle, uschar *filename, const uschar *query, int length,
  46   uschar **result, uschar **errmsg, uint *do_cache)
  47 {
  48 int error_error = FAIL;
  49 const uschar * field_name = NULL;
  50 nis_result *nrt = NULL;
  51 nis_result *nre = NULL;
  52 nis_object *tno, *eno;
  53 struct entry_obj *eo;
  54 struct table_obj *ta;
  55 const uschar * p = query + length;
  56 gstring * yield = NULL;
  57
  58 do_cache = do_cache;   /* Placate picky compilers */
  59
  60 /* Search backwards for a colon to see if a result field name
  61 has been given. */
  62
  63 while (p > query && p[-1] != ':') p--;
  64
  65 if (p > query)          /* get the query without the result-field */
  66   {
  67   uint len = p-1 - query;
  68   field_name = p;
  69   query = string_copyn(query, len);
  70   p = query + len;
  71   }
  72 else
  73   p = query + length;
  74
  75 /* Now search backwards to find the comma that starts the
  76 table name. */
  77
  78 while (p > query && p[-1] != ',') p--;
  79 if (p <= query)
  80   {
  81   *errmsg = US"NIS+ query malformed";
  82   error_error = DEFER;
  83   goto NISPLUS_EXIT;
  84   }
  85
  86 /* Look up the data for the table, in order to get the field names,
  87 check that we got back a table, and set up pointers so the field
  88 names can be scanned. */
  89
  90 nrt = nis_lookup(CS p, EXPAND_NAME | NO_CACHE);
  91 if (nrt->status != NIS_SUCCESS)
  92   {
  93   *errmsg = string_sprintf("NIS+ error accessing %s table: %s", p,
  94     nis_sperrno(nrt->status));
  95   if (nrt->status != NIS_NOTFOUND && nrt->status != NIS_NOSUCHTABLE)
  96     error_error = DEFER;
  97   goto NISPLUS_EXIT;
  98   }
  99 tno = nrt->objects.objects_val;
 100 if (tno->zo_data.zo_type != TABLE_OBJ)
 101   {
 102   *errmsg = string_sprintf("NIS+ error: %s is not a table", p);
 103   goto NISPLUS_EXIT;
 104   }
 105 ta = &tno->zo_data.objdata_u.ta_data;
 106
 107 /* Now look up the entry in the table, check that we got precisely one
 108 object and that it is a table entry. */
 109
 110 nre = nis_list(CS query, EXPAND_NAME, NULL, NULL);
 111 if (nre->status != NIS_SUCCESS)
 112   {
 113   *errmsg = string_sprintf("NIS+ error accessing entry %s: %s",
 114     query, nis_sperrno(nre->status));
 115   goto NISPLUS_EXIT;
 116   }
 117 if (nre->objects.objects_len > 1)
 118   {
 119   *errmsg = string_sprintf("NIS+ returned more than one object for %s",
 120     query);
 121   goto NISPLUS_EXIT;
 122   }
 123 else if (nre->objects.objects_len < 1)
 124   {
 125   *errmsg = string_sprintf("NIS+ returned no data for %s", query);
 126   goto NISPLUS_EXIT;
 127   }
 128 eno = nre->objects.objects_val;
 129 if (eno->zo_data.zo_type != ENTRY_OBJ)
 130   {
 131   *errmsg = string_sprintf("NIS+ error: %s is not an entry", query);
 132   goto NISPLUS_EXIT;
 133   }
 134
 135 /* Scan the columns in the entry and in the table. If a result field
 136 was given, look for that field; otherwise concatenate all the fields
 137 with their names. */
 138
 139 eo = &(eno->zo_data.objdata_u.en_data);
 140 for (int i = 0; i < eo->en_cols.en_cols_len; i++)
 141   {
 142   table_col *tc = ta->ta_cols.ta_cols_val + i;
 143   entry_col *ec = eo->en_cols.en_cols_val + i;
 144   int len = ec->ec_value.ec_value_len;
 145   uschar *value = US ec->ec_value.ec_value_val;
 146
 147   /* The value may be NULL for a zero-length field. Turn this into an
 148   empty string for consistency. Remove trailing whitespace and zero
 149   bytes. */
 150
 151   if (!value) value = US"";
 152   else
 153     while (len > 0 && (value[len-1] == 0 || isspace(value[len-1])))
 154       len--;
 155
 156   /* Concatenate all fields if no specific one selected */
 157
 158   if (!field_name)
 159     {
 160     yield = string_cat (yield, US tc->tc_name);
 161     yield = string_catn(yield, US"=", 1);
 162
 163     /* Quote the value if it contains spaces or is empty */
 164
 165     if (value[0] == 0 || Ustrchr(value, ' ') != NULL)
 166       {
 167       yield = string_catn(yield, US"\"", 1);
 168       for (int j = 0; j < len; j++)
 169         {
 170         if (value[j] == '\"' || value[j] == '\\')
 171           yield = string_catn(yield, US"\\", 1);
 172         yield = string_catn(yield, value+j, 1);
 173         }
 174       yield = string_catn(yield, US"\"", 1);
 175       }
 176     else
 177       yield = string_catn(yield, value, len);
 178
 179     yield = string_catn(yield, US" ", 1);
 180     }
 181
 182   /* When the specified field is found, grab its data and finish */
 183
 184   else if (Ustrcmp(field_name, tc->tc_name) == 0)
 185     {
 186     yield = string_catn(yield, value, len);
 187     goto NISPLUS_EXIT;
 188     }
 189   }
 190
 191 /* Error if a field name was specified and we didn't find it; if no
 192 field name, ensure the concatenated data is zero-terminated. */
 193
 194 if (field_name)
 195   *errmsg = string_sprintf("NIS+ field %s not found for %s", field_name,
 196     query);
 197 else
 198   gstring_release_unused(yield);
 199
 200 /* Free result store before finishing. */
 201
 202 NISPLUS_EXIT:
 203 if (nrt) nis_freeresult(nrt);
 204 if (nre) nis_freeresult(nre);
 205
 206 if (yield)
 207   {
 208   *result = string_from_gstring(yield);
 209   return OK;
 210   }
 211
 212 return error_error;      /* FAIL or DEFER */
 213 }
 214
 215
 216
 217 /*************************************************
 218 *               Quote entry point                *
 219 *************************************************/
 220
 221 /* The only quoting that is necessary for NIS+ is to double any doublequote
 222 characters. No options are recognized.
 223
 224 Arguments:
 225   s          the string to be quoted
 226   opt        additional option text or NULL if none
 227
 228 Returns:     the processed string or NULL for a bad option
 229 */
 230
 231 static uschar *
 232 nisplus_quote(uschar *s, uschar *opt)
 233 {
 234 int count = 0;
 235 uschar *quoted;
 236 uschar *t = s;
 237
 238 if (opt != NULL) return NULL;    /* No options recognized */
 239
 240 while (*t != 0) if (*t++ == '\"') count++;
 241 if (count == 0) return s;
 242
 243 t = quoted = store_get(Ustrlen(s) + count + 1, is_tainted(s));
 244
 245 while (*s != 0)
 246   {
 247   *t++ = *s;
 248   if (*s++ == '\"') *t++ = '\"';
 249   }
 250
 251 *t = 0;
 252 return quoted;
 253 }
 254
 255
 256 /*************************************************
 257 *         Version reporting entry point          *
 258 *************************************************/
 259
 260 /* See local README for interface description. */
 261
 262 #include "../version.h"
 263
 264 void
 265 nisplus_version_report(FILE *f)
 266 {
 267 #ifdef DYNLOOKUP
 268 fprintf(f, "Library version: NIS+: Exim version %s\n", EXIM_VERSION_STR);
 269 #endif
 270 }
 271
 272
 273 static lookup_info _lookup_info = {
 274   US"nisplus",                   /* lookup name */
 275   lookup_querystyle,             /* query-style lookup */
 276   nisplus_open,                  /* open function */
 277   NULL,                          /* check function */
 278   nisplus_find,                  /* find function */
 279   NULL,                          /* no close function */
 280   NULL,                          /* no tidy function */
 281   nisplus_quote,                 /* quoting function */
 282   nisplus_version_report         /* version reporting */
 283 };
 284
 285 #ifdef DYNLOOKUP
 286 #define nisplus_lookup_module_info _lookup_module_info
 287 #endif
 288
 289 static lookup_info *_lookup_list[] = { &_lookup_info };
 290 lookup_module_info nisplus_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
 291
 292 /* End of lookups/nisplus.c */