| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id$ |
| 4 | * |
| 5 | * Parser for `become.conf' files |
| 6 | * |
| 7 | * (c) 1998 EBI |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of `become' |
| 13 | * |
| 14 | * `Become' is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * `Become' is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with `become'; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Header files ------------------------------------------------------*/ |
| 30 | %{ |
| 31 | |
| 32 | /* --- ANSI headers --- */ |
| 33 | |
| 34 | #include <stdio.h> |
| 35 | #include <stdlib.h> |
| 36 | #include <string.h> |
| 37 | |
| 38 | /* --- Unix headers --- */ |
| 39 | |
| 40 | #include <sys/types.h> |
| 41 | #include <sys/socket.h> |
| 42 | |
| 43 | #include <netinet/in.h> |
| 44 | |
| 45 | #include <arpa/inet.h> |
| 46 | |
| 47 | #include <netdb.h> |
| 48 | #include <pwd.h> |
| 49 | #include <unistd.h> |
| 50 | |
| 51 | /* --- mLib headers --- */ |
| 52 | |
| 53 | #include <mLib/report.h> |
| 54 | #include <mLib/sym.h> |
| 55 | |
| 56 | /* --- Local headers --- */ |
| 57 | |
| 58 | #include "class.h" |
| 59 | #include "daemon.h" |
| 60 | #include "lexer.h" |
| 61 | #include "name.h" |
| 62 | #include "rule.h" |
| 63 | #include "userdb.h" |
| 64 | |
| 65 | #define YYDEBUG 1 |
| 66 | #define YYERROR_VERBOSE |
| 67 | |
| 68 | %} |
| 69 | /*----- Stack type --------------------------------------------------------*/ |
| 70 | |
| 71 | %union { |
| 72 | long i; |
| 73 | char *s; |
| 74 | name *n; |
| 75 | class_node *c; |
| 76 | } |
| 77 | |
| 78 | /*----- Token and rule declarations ---------------------------------------*/ |
| 79 | |
| 80 | /* --- Tokens --- */ |
| 81 | |
| 82 | %token BADTOKEN |
| 83 | %token USER |
| 84 | %token COMMAND |
| 85 | %token HOST |
| 86 | %token ALLOW |
| 87 | %token PORT |
| 88 | %token KEYFILE |
| 89 | %token <i> INT |
| 90 | %token <s> WORD |
| 91 | %token <s> STRING |
| 92 | %token ARROW |
| 93 | |
| 94 | %left ',' |
| 95 | %left '-' |
| 96 | %left '|' |
| 97 | %left '&' |
| 98 | |
| 99 | /* --- Rules --- */ |
| 100 | |
| 101 | %type <c> user_class command_class host_class |
| 102 | %type <c> user_class_opt command_class_opt host_class_opt |
| 103 | %type <n> name |
| 104 | |
| 105 | /*----- Error reporting ---------------------------------------------------*/ |
| 106 | %{ |
| 107 | |
| 108 | /* --- @yyprint@ --- * |
| 109 | * |
| 110 | * Arguments: @FILE *fp@ = pointer to stream to write on |
| 111 | * @int type@ = pointer to token type |
| 112 | * @YYSTYPE v@ = token value |
| 113 | * |
| 114 | * Returns: --- |
| 115 | * |
| 116 | * Use: Displays the semantic value of a token. |
| 117 | */ |
| 118 | |
| 119 | #define YYPRINT(fp, type, value) yyprint(fp, type, value) |
| 120 | |
| 121 | static void yyprint(FILE *fp, int type, YYSTYPE v) |
| 122 | { |
| 123 | switch (type) { |
| 124 | case INT: |
| 125 | fprintf(fp, " %li", v.i); |
| 126 | break; |
| 127 | case WORD: |
| 128 | case STRING: |
| 129 | fprintf(fp, " `%s'", v.s); |
| 130 | break; |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | /* --- @yyerror@ --- * |
| 135 | * |
| 136 | * Arguments: @const char *msg@ = pointer to error message |
| 137 | * |
| 138 | * Returns: --- |
| 139 | * |
| 140 | * Use: Reports parse errors. |
| 141 | */ |
| 142 | |
| 143 | static void yyerror(const char *msg) |
| 144 | { |
| 145 | moan("%s at line %i", msg, lex_line); |
| 146 | } |
| 147 | |
| 148 | %} |
| 149 | %% |
| 150 | /*----- The actual grammar ------------------------------------------------*/ |
| 151 | |
| 152 | /* --- Simple driver things --- */ |
| 153 | |
| 154 | file : /* empty */ |
| 155 | | file statement |
| 156 | ; |
| 157 | |
| 158 | statement : user_spec |
| 159 | | command_spec |
| 160 | | host_spec |
| 161 | | allow_spec |
| 162 | | port_spec |
| 163 | | key_spec |
| 164 | | error ';' |
| 165 | ; |
| 166 | |
| 167 | /* --- Main statement types --- */ |
| 168 | |
| 169 | user_spec : USER name '=' user_class ';' { |
| 170 | if ($2->c) |
| 171 | class_dec($2->c); |
| 172 | $2->c = $4; |
| 173 | } |
| 174 | ; |
| 175 | |
| 176 | command_spec : COMMAND name '=' command_class ';' { |
| 177 | if ($2->c) |
| 178 | class_dec($2->c); |
| 179 | $2->c = $4; |
| 180 | } |
| 181 | ; |
| 182 | |
| 183 | host_spec : HOST name '=' host_class ';' { |
| 184 | if ($2->c) |
| 185 | class_dec($2->c); |
| 186 | $2->c = $4; |
| 187 | } |
| 188 | ; |
| 189 | |
| 190 | port_spec : PORT STRING ';' { |
| 191 | #ifndef NONETWORK |
| 192 | struct servent *s = getservbyname($2, "udp"); |
| 193 | if (!s) { |
| 194 | moan("unknown service `%s' at line %i", |
| 195 | $2, lex_line); |
| 196 | yynerrs++; YYERROR; |
| 197 | } |
| 198 | daemon_usePort(s->s_port); |
| 199 | #else |
| 200 | yyerror("`port' command unsupported"); |
| 201 | yynerrs++; YYERROR; |
| 202 | #endif |
| 203 | } |
| 204 | | PORT INT ';' { |
| 205 | #ifndef NONETWORK |
| 206 | daemon_usePort(htons($2)); |
| 207 | #else |
| 208 | yyerror("`port' command unsupported"); |
| 209 | yynerrs++; YYERROR; |
| 210 | #endif |
| 211 | } |
| 212 | ; |
| 213 | |
| 214 | key_spec : KEYFILE STRING ';' { |
| 215 | #ifndef NONETWORK |
| 216 | daemon_readKey($2); |
| 217 | #else |
| 218 | yyerror("`keyfile' command unsupported"); |
| 219 | yynerrs++; YYERROR; |
| 220 | #endif |
| 221 | } |
| 222 | ; |
| 223 | |
| 224 | /* --- Parsing allow specifications --- */ |
| 225 | |
| 226 | allow_spec : ALLOW host_class_opt user_class ARROW |
| 227 | user_class_opt command_class_opt ';' { |
| 228 | rule_add($2, $3, $5, $6); |
| 229 | } |
| 230 | ; |
| 231 | |
| 232 | host_class_opt : /* empty */ { $$ = class_all; } |
| 233 | | '[' host_class ']' { $$ = $2; } |
| 234 | ; |
| 235 | |
| 236 | user_class_opt : /* empty */ { $$ = class_all; } |
| 237 | | user_class { $$ = $1; } |
| 238 | ; |
| 239 | |
| 240 | command_class_opt : /* empty */ { $$ = class_all; } |
| 241 | | ':' command_class { $$ = $2; } |
| 242 | ; |
| 243 | |
| 244 | /* --- Names get translated into symbols quickly --- */ |
| 245 | |
| 246 | name : WORD { |
| 247 | unsigned f; |
| 248 | name *n = name_find($1, 1, &f); |
| 249 | if (!f) |
| 250 | n->c = 0; |
| 251 | $$ = n; |
| 252 | } |
| 253 | ; |
| 254 | |
| 255 | /*----- Various class expression types ------------------------------------* |
| 256 | * |
| 257 | * Unfortunately, all these need to handle token types slightly differently |
| 258 | * and I can't be bothered to remember the current state. |
| 259 | */ |
| 260 | |
| 261 | /* --- User class expressions --- */ |
| 262 | |
| 263 | user_class : user_class ',' user_class { |
| 264 | if (($$ = class_union($1, $3)) == 0) { |
| 265 | yyerror("type mismatch"); |
| 266 | yynerrs++; YYERROR; |
| 267 | } |
| 268 | } |
| 269 | | user_class '-' user_class { |
| 270 | if (($$ = class_diff($1, $3)) == 0) { |
| 271 | yyerror("type mismatch"); |
| 272 | yynerrs++; YYERROR; |
| 273 | } |
| 274 | } |
| 275 | | user_class '&' user_class { |
| 276 | if (($$ = class_isect($1, $3)) == 0) { |
| 277 | yyerror("type mismatch"); |
| 278 | yynerrs++; YYERROR; |
| 279 | } |
| 280 | } |
| 281 | | user_class '|' user_class { |
| 282 | if (($$ = class_union($1, $3)) == 0) { |
| 283 | yyerror("type mismatch"); |
| 284 | yynerrs++; YYERROR; |
| 285 | } |
| 286 | } |
| 287 | | INT { $$ = class_fromUser(clType_user, $1); } |
| 288 | | STRING { |
| 289 | struct passwd *pw; |
| 290 | if ((pw = userdb_userByName($1)) == 0) { |
| 291 | moan("user `%s' not known at line %i", |
| 292 | $1, lex_line); |
| 293 | yynerrs++; YYERROR; |
| 294 | } else |
| 295 | $$ = class_fromUser(clType_user, pw->pw_uid); |
| 296 | } |
| 297 | | WORD { |
| 298 | name *n = name_find($1, 0, 0); |
| 299 | if (!n || !n->c) { |
| 300 | moan("class `%s' not found at line %i", |
| 301 | $1, lex_line); |
| 302 | yynerrs++; YYERROR; |
| 303 | } else if (~n->c->type & clType_user) { |
| 304 | yynerrs++; yyerror("type mismatch"); |
| 305 | yynerrs++; YYERROR; |
| 306 | } else { |
| 307 | $$ = n->c; |
| 308 | class_inc(n->c); |
| 309 | } |
| 310 | } |
| 311 | | '(' user_class ')' { $$ = $2; } |
| 312 | ; |
| 313 | |
| 314 | /* --- Command class expressions --- */ |
| 315 | |
| 316 | command_class : command_class ',' command_class { |
| 317 | if (($$ = class_union($1, $3)) == 0) { |
| 318 | yyerror("type mismatch"); |
| 319 | yynerrs++; YYERROR; |
| 320 | } |
| 321 | } |
| 322 | | command_class '-' command_class { |
| 323 | if (($$ = class_diff($1, $3)) == 0) { |
| 324 | yyerror("type mismatch"); |
| 325 | yynerrs++; YYERROR; |
| 326 | } |
| 327 | } |
| 328 | | command_class '&' command_class { |
| 329 | if (($$ = class_isect($1, $3)) == 0) { |
| 330 | yyerror("type mismatch"); |
| 331 | yynerrs++; YYERROR; |
| 332 | } |
| 333 | } |
| 334 | | command_class '|' command_class { |
| 335 | if (($$ = class_union($1, $3)) == 0) { |
| 336 | yyerror("type mismatch"); |
| 337 | yynerrs++; YYERROR; |
| 338 | } |
| 339 | } |
| 340 | | STRING { $$ = class_fromString(clType_command, $1); } |
| 341 | | WORD { |
| 342 | name *n = name_find($1, 0, 0); |
| 343 | if (!n || !n->c) { |
| 344 | moan("class `%s' not found at line %i", |
| 345 | $1, lex_line); |
| 346 | yynerrs++; YYERROR; |
| 347 | } else if (~n->c->type & clType_command) { |
| 348 | yyerror("type mismatch"); |
| 349 | yynerrs++; YYERROR; |
| 350 | } else { |
| 351 | $$ = n->c; |
| 352 | class_inc(n->c); |
| 353 | } |
| 354 | } |
| 355 | | '(' command_class ')' { $$ = $2; } |
| 356 | ; |
| 357 | |
| 358 | /* --- Host class expressions --- */ |
| 359 | |
| 360 | host_class : host_class ',' host_class { |
| 361 | if (($$ = class_union($1, $3)) == 0) { |
| 362 | yyerror("type mismatch"); |
| 363 | yynerrs++; YYERROR; |
| 364 | } |
| 365 | } |
| 366 | | host_class '-' host_class { |
| 367 | if (($$ = class_diff($1, $3)) == 0) { |
| 368 | yyerror("type mismatch"); |
| 369 | yynerrs++; YYERROR; |
| 370 | } |
| 371 | } |
| 372 | | host_class '&' host_class { |
| 373 | if (($$ = class_isect($1, $3)) == 0) { |
| 374 | yyerror("type mismatch"); |
| 375 | yynerrs++; YYERROR; |
| 376 | } |
| 377 | } |
| 378 | | host_class '|' host_class { |
| 379 | if (($$ = class_union($1, $3)) == 0) { |
| 380 | yyerror("type mismatch"); |
| 381 | yynerrs++; YYERROR; |
| 382 | } |
| 383 | } |
| 384 | | STRING { $$ = class_fromString(clType_host, $1); } |
| 385 | | WORD { |
| 386 | name *n = name_find($1, 0, 0); |
| 387 | if (!n || !n->c) { |
| 388 | moan("class `%s' not found at line %i", |
| 389 | $1, lex_line); |
| 390 | yynerrs++; YYERROR; |
| 391 | } else if (~n->c->type & clType_host) { |
| 392 | yyerror("type mismatch"); |
| 393 | yynerrs++; YYERROR; |
| 394 | } else { |
| 395 | $$ = n->c; |
| 396 | class_inc(n->c); |
| 397 | } |
| 398 | } |
| 399 | | '(' host_class ')' { $$ = $2; } |
| 400 | ; |
| 401 | |
| 402 | /*----- Helper functions --------------------------------------------------*/ |
| 403 | %% |
| 404 | /* --- @parse@ --- * |
| 405 | * |
| 406 | * Arguments: --- |
| 407 | * |
| 408 | * Returns: Zero if it worked, nonzero if it didn't. |
| 409 | * |
| 410 | * Use: Parses configuration files. |
| 411 | */ |
| 412 | |
| 413 | int parse(void) |
| 414 | { |
| 415 | yynerrs = 0; |
| 416 | return (yyparse() || yynerrs); |
| 417 | } |
| 418 | |
| 419 | /*----- That's all, folks -------------------------------------------------*/ |