1 /* 2 * a generic (simple) parser. Use to parse rr's, private key 3 * information and /etc/resolv.conf files 4 * 5 * a Net::DNS like library for C 6 * LibDNS Team @ NLnet Labs 7 * (c) NLnet Labs, 2005-2006 8 * See the file LICENSE for the license 9 */ 10 #include <ldns/config.h> 11 #include <ldns/ldns.h> 12 13 #include <limits.h> 14 #include <strings.h> 15 16 ldns_lookup_table ldns_directive_types[] = { 17 { LDNS_DIR_TTL, "$TTL" }, 18 { LDNS_DIR_ORIGIN, "$ORIGIN" }, 19 { LDNS_DIR_INCLUDE, "$INCLUDE" }, 20 { 0, NULL } 21 }; 22 23 /* add max_limit here? */ 24 ssize_t 25 ldns_fget_token(FILE *f, char *token, const char *delim, size_t limit) 26 { 27 return ldns_fget_token_l(f, token, delim, limit, NULL); 28 } 29 30 ssize_t 31 ldns_fget_token_l(FILE *f, char *token, const char *delim, size_t limit, int *line_nr) 32 { 33 int c, prev_c; 34 int p; /* 0 -> no parenthese seen, >0 nr of ( seen */ 35 int com, quoted; 36 char *t; 37 size_t i; 38 const char *d; 39 const char *del; 40 41 /* standard delimeters */ 42 if (!delim) { 43 /* from isspace(3) */ 44 del = LDNS_PARSE_NORMAL; 45 } else { 46 del = delim; 47 } 48 49 p = 0; 50 i = 0; 51 com = 0; 52 quoted = 0; 53 prev_c = 0; 54 t = token; 55 if (del[0] == '"') { 56 quoted = 1; 57 } 58 while ((c = getc(f)) != EOF) { 59 if (c == '(' && prev_c != '\\' && !quoted) { 60 /* this only counts for non-comments */ 61 if (com == 0) { 62 p++; 63 } 64 prev_c = c; 65 continue; 66 } 67 68 if (c == ')' && prev_c != '\\' && !quoted) { 69 /* this only counts for non-comments */ 70 if (com == 0) { 71 p--; 72 } 73 prev_c = c; 74 continue; 75 } 76 77 if (p < 0) { 78 /* more ) then ( - close off the string */ 79 *t = '\0'; 80 return 0; 81 } 82 83 /* do something with comments ; */ 84 if (c == ';' && quoted == 0) { 85 if (prev_c != '\\') { 86 com = 1; 87 } 88 } 89 if (c == '\"' && com == 0 && prev_c != '\\') { 90 quoted = 1 - quoted; 91 } 92 93 if (c == '\n' && com != 0) { 94 /* comments */ 95 com = 0; 96 *t = ' '; 97 if (line_nr) { 98 *line_nr = *line_nr + 1; 99 } 100 if (p == 0 && i > 0) { 101 goto tokenread; 102 } else { 103 prev_c = c; 104 continue; 105 } 106 } 107 108 if (com == 1) { 109 *t = ' '; 110 prev_c = c; 111 continue; 112 } 113 114 115 if (c == '\n' && p != 0 && t > token) { 116 /* in parentheses */ 117 if (line_nr) { 118 *line_nr = *line_nr + 1; 119 } 120 *t++ = ' '; 121 prev_c = c; 122 continue; 123 } 124 125 /* check if we hit the delim */ 126 for (d = del; *d; d++) { 127 if (c == *d && i > 0 && prev_c != '\\') { 128 if (c == '\n' && line_nr) { 129 *line_nr = *line_nr + 1; 130 } 131 goto tokenread; 132 } 133 } 134 if (c != '\0' && c != '\n') { 135 *t++ = c; 136 i++; 137 } 138 if (limit > 0 && i >= limit) { 139 *t = '\0'; 140 return -1; 141 } 142 if (c == '\\' && prev_c == '\\') 143 prev_c = 0; 144 else prev_c = c; 145 } 146 *t = '\0'; 147 if (c == EOF) { 148 return (ssize_t)i; 149 } 150 151 if (i == 0) { 152 /* nothing read */ 153 return -1; 154 } 155 if (p != 0) { 156 return -1; 157 } 158 return (ssize_t)i; 159 160 tokenread: 161 ldns_fskipcs_l(f, delim, line_nr); 162 *t = '\0'; 163 if (p != 0) { 164 return -1; 165 } 166 167 return (ssize_t)i; 168 } 169 170 ssize_t 171 ldns_fget_keyword_data(FILE *f, const char *keyword, const char *k_del, char *data, 172 const char *d_del, size_t data_limit) 173 { 174 return ldns_fget_keyword_data_l(f, keyword, k_del, data, d_del, 175 data_limit, NULL); 176 } 177 178 ssize_t 179 ldns_fget_keyword_data_l(FILE *f, const char *keyword, const char *k_del, char *data, 180 const char *d_del, size_t data_limit, int *line_nr) 181 { 182 /* we assume: keyword|sep|data */ 183 char *fkeyword; 184 ssize_t i; 185 186 fkeyword = LDNS_XMALLOC(char, LDNS_MAX_KEYWORDLEN); 187 if(!fkeyword) 188 return -1; 189 190 i = ldns_fget_token(f, fkeyword, k_del, LDNS_MAX_KEYWORDLEN); 191 if(i==0 || i==-1) { 192 LDNS_FREE(fkeyword); 193 return -1; 194 } 195 196 /* case??? i instead of strlen? */ 197 if (strncmp(fkeyword, keyword, LDNS_MAX_KEYWORDLEN - 1) == 0) { 198 /* whee! */ 199 /* printf("%s\n%s\n", "Matching keyword", fkeyword); */ 200 i = ldns_fget_token_l(f, data, d_del, data_limit, line_nr); 201 LDNS_FREE(fkeyword); 202 return i; 203 } else { 204 /*printf("no match for %s (read: %s)\n", keyword, fkeyword);*/ 205 LDNS_FREE(fkeyword); 206 return -1; 207 } 208 } 209 210 211 ssize_t 212 ldns_bget_token(ldns_buffer *b, char *token, const char *delim, size_t limit) 213 { 214 int c, lc; 215 int p; /* 0 -> no parenthese seen, >0 nr of ( seen */ 216 int com, quoted; 217 char *t; 218 size_t i; 219 const char *d; 220 const char *del; 221 222 /* standard delimiters */ 223 if (!delim) { 224 /* from isspace(3) */ 225 del = LDNS_PARSE_NORMAL; 226 } else { 227 del = delim; 228 } 229 230 p = 0; 231 i = 0; 232 com = 0; 233 quoted = 0; 234 t = token; 235 lc = 0; 236 if (del[0] == '"') { 237 quoted = 1; 238 } 239 240 while ((c = ldns_bgetc(b)) != EOF) { 241 if (c == '(' && lc != '\\' && !quoted) { 242 /* this only counts for non-comments */ 243 if (com == 0) { 244 p++; 245 } 246 lc = c; 247 continue; 248 } 249 250 if (c == ')' && lc != '\\' && !quoted) { 251 /* this only counts for non-comments */ 252 if (com == 0) { 253 p--; 254 } 255 lc = c; 256 continue; 257 } 258 259 if (p < 0) { 260 /* more ) then ( */ 261 *t = '\0'; 262 return 0; 263 } 264 265 /* do something with comments ; */ 266 if (c == ';' && quoted == 0) { 267 if (lc != '\\') { 268 com = 1; 269 } 270 } 271 if (c == '"' && com == 0 && lc != '\\') { 272 quoted = 1 - quoted; 273 } 274 275 if (c == '\n' && com != 0) { 276 /* comments */ 277 com = 0; 278 *t = ' '; 279 lc = c; 280 continue; 281 } 282 283 if (com == 1) { 284 *t = ' '; 285 lc = c; 286 continue; 287 } 288 289 if (c == '\n' && p != 0) { 290 /* in parentheses */ 291 *t++ = ' '; 292 lc = c; 293 continue; 294 } 295 296 /* check if we hit the delim */ 297 for (d = del; *d; d++) { 298 if (c == *d && lc != '\\') { 299 goto tokenread; 300 } 301 } 302 303 *t++ = c; 304 i++; 305 if (limit > 0 && i >= limit) { 306 *t = '\0'; 307 return -1; 308 } 309 310 if (c == '\\' && lc == '\\') { 311 lc = 0; 312 } else { 313 lc = c; 314 } 315 } 316 *t = '\0'; 317 if (i == 0) { 318 /* nothing read */ 319 return -1; 320 } 321 if (p != 0) { 322 return -1; 323 } 324 return (ssize_t)i; 325 326 tokenread: 327 ldns_bskipcs(b, delim); 328 *t = '\0'; 329 330 if (p != 0) { 331 return -1; 332 } 333 return (ssize_t)i; 334 } 335 336 void 337 ldns_bskipc(ldns_buffer *buffer, char c) 338 { 339 while (c == (char) ldns_buffer_read_u8_at(buffer, ldns_buffer_position(buffer))) { 340 if (ldns_buffer_available_at(buffer, 341 buffer->_position + sizeof(char), sizeof(char))) { 342 buffer->_position += sizeof(char); 343 } else { 344 return; 345 } 346 } 347 } 348 349 void 350 ldns_bskipcs(ldns_buffer *buffer, const char *s) 351 { 352 bool found; 353 char c; 354 const char *d; 355 356 while(ldns_buffer_available_at(buffer, buffer->_position, sizeof(char))) { 357 c = (char) ldns_buffer_read_u8_at(buffer, buffer->_position); 358 found = false; 359 for (d = s; *d; d++) { 360 if (*d == c) { 361 found = true; 362 } 363 } 364 if (found && buffer->_limit > buffer->_position) { 365 buffer->_position += sizeof(char); 366 } else { 367 return; 368 } 369 } 370 } 371 372 void 373 ldns_fskipc(FILE *fp, char c) 374 { 375 fp = fp; 376 c = c; 377 } 378 379 380 void 381 ldns_fskipcs(FILE *fp, const char *s) 382 { 383 ldns_fskipcs_l(fp, s, NULL); 384 } 385 386 void 387 ldns_fskipcs_l(FILE *fp, const char *s, int *line_nr) 388 { 389 bool found; 390 int c; 391 const char *d; 392 393 while ((c = fgetc(fp)) != EOF) { 394 if (line_nr && c == '\n') { 395 *line_nr = *line_nr + 1; 396 } 397 found = false; 398 for (d = s; *d; d++) { 399 if (*d == c) { 400 found = true; 401 } 402 } 403 if (!found) { 404 /* with getc, we've read too far */ 405 ungetc(c, fp); 406 return; 407 } 408 } 409 } 410 411 ssize_t 412 ldns_bget_keyword_data(ldns_buffer *b, const char *keyword, const char *k_del, char 413 *data, const char *d_del, size_t data_limit) 414 { 415 /* we assume: keyword|sep|data */ 416 char *fkeyword; 417 ssize_t i; 418 419 fkeyword = LDNS_XMALLOC(char, LDNS_MAX_KEYWORDLEN); 420 if(!fkeyword) 421 return -1; /* out of memory */ 422 423 i = ldns_bget_token(b, fkeyword, k_del, data_limit); 424 if(i==0 || i==-1) { 425 LDNS_FREE(fkeyword); 426 return -1; /* nothing read */ 427 } 428 429 /* case??? */ 430 if (strncmp(fkeyword, keyword, strlen(keyword)) == 0) { 431 LDNS_FREE(fkeyword); 432 /* whee, the match! */ 433 /* retrieve it's data */ 434 i = ldns_bget_token(b, data, d_del, 0); 435 return i; 436 } else { 437 LDNS_FREE(fkeyword); 438 return -1; 439 } 440 } 441 442