source3/rpc_server/mdssvc/sparql_parser.y

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Main metadata server / Spotlight routines
   4
   5    Copyright (C) Ralph Boehme 2012-2014
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 %{
  22         #include "includes.h"
  23         #include "rpc_server/mdssvc/mdssvc.h"
  24         #include "rpc_server/mdssvc/mdssvc_tracker.h"
  25         #include "rpc_server/mdssvc/sparql_parser.tab.h"
  26         #include "rpc_server/mdssvc/sparql_mapping.h"
  27
  28         #define YYMALLOC SMB_MALLOC
  29         #define YYREALLOC SMB_REALLOC
  30
  31         struct yy_buffer_state;
  32         typedef struct yy_buffer_state *YY_BUFFER_STATE;
  33         extern int mdsyylex (void);
  34         extern void mdsyyerror (char const *);
  35         extern void *mdsyyterminate(void);
  36         extern YY_BUFFER_STATE mdsyy_scan_string( const char *str);
  37         extern void mdsyy_delete_buffer ( YY_BUFFER_STATE buffer );
  38
  39         /* forward declarations */
  40         static const char *map_expr(const char *attr, char op, const char *val);
  41         static const char *map_daterange(const char *dateattr,
  42                                          time_t date1, time_t date2);
  43         static time_t isodate2unix(const char *s);
  44
  45         /* global vars, eg needed by the lexer */
  46         struct sparql_parser_state {
  47                 TALLOC_CTX *frame;
  48                 YY_BUFFER_STATE s;
  49                 char var;
  50                 const char *result;
  51         } *global_sparql_parser_state;
  52 %}
  53
  54 %code provides {
  55         #include <stdbool.h>
  56         #include "rpc_server/mdssvc/mdssvc.h"
  57         #define SPRAW_TIME_OFFSET 978307200
  58         extern int mdsyywrap(void);
  59         extern bool map_spotlight_to_sparql_query(struct sl_query *slq);
  60 }
  61
  62 %union {
  63         int ival;
  64         const char *sval;
  65         bool bval;
  66         time_t tval;
  67 }
  68
  69 %define api.prefix {mdsyy}
  70 %expect 5
  71 %define parse.error verbose
  72
  73 %type <sval> match expr line function
  74 %type <tval> date
  75
  76 %token <sval> WORD
  77 %token <bval> BOOL
  78 %token FUNC_INRANGE
  79 %token DATE_ISO
  80 %token OBRACE CBRACE EQUAL UNEQUAL GT LT COMMA QUOTE
  81 %left AND
  82 %left OR
  83 %%
  84
  85 input:
  86 /* empty */
  87 | input line
  88 ;
  89
  90 line:
  91 expr {
  92         global_sparql_parser_state->result = $1;
  93 }
  94 ;
  95
  96 expr:
  97 BOOL {
  98         /*
  99          * We can't properly handle these in expressions, fortunately this
 100          * is probably only ever used by OS X as sole element in an
 101          * expression ie "False" (when Finder window selected our share
 102          * but no search string entered yet). Packet traces showed that OS
 103          * X Spotlight server then returns a failure (ie -1) which is what
 104          * we do here too by calling YYABORT.
 105          */
 106         YYABORT;
 107 }
 108 /*
 109  * We have "match OR match" and "expr OR expr", because the former is
 110  * supposed to catch and coalesque expressions of the form
 111  *
 112  *   MDSattribute1="hello"||MDSattribute2="hello"
 113  *
 114  * into a single SPARQL expression for the case where both
 115  * MDSattribute1 and MDSattribute2 map to the same SPARQL attribute,
 116  * which is eg the case for "*" and "kMDItemTextContent" which both
 117  * map to SPARQL "fts:match".
 118  */
 119
 120 | match OR match {
 121         if (strcmp($1, $3) != 0) {
 122                 $$ = talloc_asprintf(talloc_tos(), "{ %s } UNION { %s }", $1, $3);
 123         } else {
 124                 $$ = talloc_asprintf(talloc_tos(), "%s", $1);
 125         }
 126 }
 127 | match {
 128         $$ = $1;
 129 }
 130 | function {
 131         $$ = $1;
 132 }
 133 | OBRACE expr CBRACE {
 134         $$ = talloc_asprintf(talloc_tos(), "%s", $2);
 135 }
 136 | expr AND expr {
 137         $$ = talloc_asprintf(talloc_tos(), "%s . %s", $1, $3);
 138 }
 139 | expr OR expr {
 140         if (strcmp($1, $3) != 0) {
 141                 $$ = talloc_asprintf(talloc_tos(), "{ %s } UNION { %s }", $1, $3);
 142         } else {
 143                 $$ = talloc_asprintf(talloc_tos(), "%s", $1);
 144         }
 145 }
 146 ;
 147
 148 match:
 149 WORD EQUAL QUOTE WORD QUOTE {
 150         $$ = map_expr($1, '=', $4);
 151         if ($$ == NULL) YYABORT;
 152 }
 153 | WORD UNEQUAL QUOTE WORD QUOTE {
 154         $$ = map_expr($1, '!', $4);
 155         if ($$ == NULL) YYABORT;
 156 }
 157 | WORD LT QUOTE WORD QUOTE {
 158         $$ = map_expr($1, '<', $4);
 159         if ($$ == NULL) YYABORT;
 160 }
 161 | WORD GT QUOTE WORD QUOTE {
 162         $$ = map_expr($1, '>', $4);
 163         if ($$ == NULL) YYABORT;
 164 }
 165 | WORD EQUAL QUOTE WORD QUOTE WORD {
 166         $$ = map_expr($1, '=', $4);
 167         if ($$ == NULL) YYABORT;
 168 }
 169 | WORD UNEQUAL QUOTE WORD QUOTE WORD {
 170         $$ = map_expr($1, '!', $4);
 171         if ($$ == NULL) YYABORT;
 172 }
 173 | WORD LT QUOTE WORD QUOTE WORD {
 174         $$ = map_expr($1, '<', $4);
 175         if ($$ == NULL) YYABORT;
 176 }
 177 | WORD GT QUOTE WORD QUOTE WORD {
 178         $$ = map_expr($1, '>', $4);
 179         if ($$ == NULL) YYABORT;
 180 }
 181 ;
 182
 183 function:
 184 FUNC_INRANGE OBRACE WORD COMMA date COMMA date CBRACE {
 185         $$ = map_daterange($3, $5, $7);
 186         if ($$ == NULL) YYABORT;
 187 }
 188 ;
 189
 190 date:
 191 DATE_ISO OBRACE WORD CBRACE    {$$ = isodate2unix($3);}
 192 | WORD                         {$$ = atoi($1) + SPRAW_TIME_OFFSET;}
 193 ;
 194
 195 %%
 196
 197 static time_t isodate2unix(const char *s)
 198 {
 199         struct tm tm = {};
 200         const char *p;
 201
 202         p = strptime(s, "%Y-%m-%dT%H:%M:%SZ", &tm);
 203         if (p == NULL) {
 204                 return (time_t)-1;
 205         }
 206         return mktime(&tm);
 207 }
 208
 209 static const char *map_daterange(const char *dateattr,
 210                                  time_t date1, time_t date2)
 211 {
 212         struct sparql_parser_state *s = global_sparql_parser_state;
 213         int result = 0;
 214         char *sparql = NULL;
 215         const struct sl_attr_map *p;
 216         struct tm *tmp;
 217         char buf1[64], buf2[64];
 218
 219         if (s->var == 'z') {
 220                 return NULL;
 221         }
 222
 223         tmp = localtime(&date1);
 224         if (tmp == NULL) {
 225                 return NULL;
 226         }
 227         result = strftime(buf1, sizeof(buf1), "%Y-%m-%dT%H:%M:%SZ", tmp);
 228         if (result == 0) {
 229                 return NULL;
 230         }
 231
 232         tmp = localtime(&date2);
 233         if (tmp == NULL) {
 234                 return NULL;
 235         }
 236         result = strftime(buf2, sizeof(buf2), "%Y-%m-%dT%H:%M:%SZ", tmp);
 237         if (result == 0) {
 238                 return NULL;
 239         }
 240
 241         p = sl_attr_map_by_spotlight(dateattr);
 242         if (p == NULL) {
 243                 return NULL;
 244         }
 245
 246         sparql = talloc_asprintf(talloc_tos(),
 247                                  "?obj %s ?%c FILTER (?%c > '%s' && ?%c < '%s')",
 248                                  p->sparql_attr,
 249                                  s->var,
 250                                  s->var,
 251                                  buf1,
 252                                  s->var,
 253                                  buf2);
 254         if (sparql == NULL) {
 255                 return NULL;
 256         }
 257
 258         s->var++;
 259         return sparql;
 260 }
 261
 262 static char *map_type_search(const char *attr, char op, const char *val)
 263 {
 264         char *result = NULL;
 265         const char *sparqlAttr;
 266         const struct sl_type_map *p;
 267
 268         p = sl_type_map_by_spotlight(val);
 269         if (p == NULL) {
 270                 return NULL;
 271         }
 272
 273         switch (p->type) {
 274         case kMDTypeMapRDF:
 275                 sparqlAttr = "rdf:type";
 276                 break;
 277         case kMDTypeMapMime:
 278                 sparqlAttr = "nie:mimeType";
 279                 break;
 280         default:
 281                 return NULL;
 282         }
 283
 284         result = talloc_asprintf(talloc_tos(), "?obj %s '%s'",
 285                                  sparqlAttr,
 286                                  p->sparql_type);
 287         if (result == NULL) {
 288                 return NULL;
 289         }
 290
 291         return result;
 292 }
 293
 294 static const char *map_expr(const char *attr, char op, const char *val)
 295 {
 296         struct sparql_parser_state *s = global_sparql_parser_state;
 297         int result = 0;
 298         char *sparql = NULL;
 299         const struct sl_attr_map *p;
 300         time_t t;
 301         struct tm *tmp;
 302         char buf1[64];
 303         char *q;
 304         const char *start;
 305
 306         if (s->var == 'z') {
 307                 return NULL;
 308         }
 309
 310         p = sl_attr_map_by_spotlight(attr);
 311         if (p == NULL) {
 312                 return NULL;
 313         }
 314
 315         if ((p->type != ssmt_type) && (p->sparql_attr == NULL)) {
 316                 yyerror("unsupported Spotlight attribute");
 317                 return NULL;
 318         }
 319
 320         switch (p->type) {
 321         case ssmt_bool:
 322                 sparql = talloc_asprintf(talloc_tos(), "?obj %s '%s'",
 323                                          p->sparql_attr, val);
 324                 if (sparql == NULL) {
 325                         return NULL;
 326                 }
 327                 break;
 328
 329         case ssmt_num:
 330                 sparql = talloc_asprintf(talloc_tos(),
 331                                          "?obj %s ?%c FILTER(?%c %c%c '%s')",
 332                                          p->sparql_attr,
 333                                          s->var,
 334                                          s->var,
 335                                          op,
 336                                          /* append '=' to '!' */
 337                                          op == '!' ? '=' : ' ',
 338                                          val);
 339                 if (sparql == NULL) {
 340                         return NULL;
 341                 }
 342                 s->var++;
 343                 break;
 344
 345         case ssmt_str:
 346                 q = talloc_strdup(talloc_tos(), "");
 347                 if (q == NULL) {
 348                         return NULL;
 349                 }
 350                 start = val;
 351                 while (*val) {
 352                         if (*val != '*') {
 353                                 val++;
 354                                 continue;
 355                         }
 356                         if (val > start) {
 357                                 q = talloc_strndup_append(q, start, val - start);
 358                                 if (q == NULL) {
 359                                         return NULL;
 360                                 }
 361                         }
 362                         q = talloc_strdup_append(q, ".*");
 363                         if (q == NULL) {
 364                                 return NULL;
 365                         }
 366                         val++;
 367                         start = val;
 368                 }
 369                 if (val > start) {
 370                         q = talloc_strndup_append(q, start, val - start);
 371                         if (q == NULL) {
 372                                 return NULL;
 373                         }
 374                 }
 375                 sparql = talloc_asprintf(talloc_tos(),
 376                                          "?obj %s ?%c "
 377                                          "FILTER(regex(?%c, '^%s$', 'i'))",
 378                                          p->sparql_attr,
 379                                          s->var,
 380                                          s->var,
 381                                          q);
 382                 TALLOC_FREE(q);
 383                 if (sparql == NULL) {
 384                         return NULL;
 385                 }
 386                 s->var++;
 387                 break;
 388
 389         case ssmt_fts:
 390                 sparql = talloc_asprintf(talloc_tos(), "?obj %s '%s'",
 391                                          p->sparql_attr, val);
 392                 if (sparql == NULL) {
 393                         return NULL;
 394                 }
 395                 break;
 396
 397         case ssmt_date:
 398                 t = atoi(val) + SPRAW_TIME_OFFSET;
 399                 tmp = localtime(&t);
 400                 if (tmp == NULL) {
 401                         return NULL;
 402                 }
 403                 result = strftime(buf1, sizeof(buf1),
 404                                   "%Y-%m-%dT%H:%M:%SZ", tmp);
 405                 if (result == 0) {
 406                         return NULL;
 407                 }
 408                 sparql = talloc_asprintf(talloc_tos(),
 409                                          "?obj %s ?%c FILTER(?%c %c '%s')",
 410                                          p->sparql_attr,
 411                                          s->var,
 412                                          s->var,
 413                                          op,
 414                                          buf1);
 415                 if (sparql == NULL) {
 416                         return NULL;
 417                 }
 418                 s->var++;
 419                 break;
 420
 421         case ssmt_type:
 422                 sparql = map_type_search(attr, op, val);
 423                 if (sparql == NULL) {
 424                         return NULL;
 425                 }
 426                 break;
 427
 428         default:
 429                 return NULL;
 430         }
 431
 432         return sparql;
 433 }
 434
 435 void mdsyyerror(const char *str)
 436 {
 437         DEBUG(1, ("mdsyyerror: %s\n", str));
 438 }
 439
 440 int mdsyywrap(void)
 441 {
 442         return 1;
 443 }
 444
 445 /**
 446  * Map a Spotlight RAW query string to a SPARQL query string
 447  **/
 448 bool map_spotlight_to_sparql_query(struct sl_query *slq)
 449 {
 450         struct sl_tracker_query *tq = talloc_get_type_abort(
 451                 slq->backend_private, struct sl_tracker_query);
 452         struct sparql_parser_state s = {
 453                 .frame = talloc_stackframe(),
 454                 .var = 'a',
 455         };
 456         int result;
 457
 458         s.s = mdsyy_scan_string(slq->query_string);
 459         if (s.s == NULL) {
 460                 TALLOC_FREE(s.frame);
 461                 return false;
 462         }
 463         global_sparql_parser_state = &s;
 464         result = mdsyyparse();
 465         global_sparql_parser_state = NULL;
 466         mdsyy_delete_buffer(s.s);
 467
 468         if (result != 0) {
 469                 TALLOC_FREE(s.frame);
 470                 return false;
 471         }
 472
 473         tq->sparql_query = talloc_asprintf(slq,
 474                 "SELECT ?url WHERE { %s . ?obj nie:url ?url . "
 475                 "FILTER(tracker:uri-is-descendant('file://%s/', ?url)) }",
 476                 s.result, tq->path_scope);
 477         TALLOC_FREE(s.frame);
 478         if (tq->sparql_query == NULL) {
 479                 return false;
 480         }
 481
 482         return true;
 483 }