| 1 | /* |
| 2 | ashd - A Sane HTTP Daemon |
| 3 | Copyright (C) 2008 Fredrik Tolf <fredrik@dolda2000.com> |
| 4 | |
| 5 | This program is free software: you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation, either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 17 | */ |
| 18 | |
| 19 | #include <stdlib.h> |
| 20 | #include <stdio.h> |
| 21 | #include <string.h> |
| 22 | #include <unistd.h> |
| 23 | #include <signal.h> |
| 24 | #include <errno.h> |
| 25 | #include <ctype.h> |
| 26 | #include <regex.h> |
| 27 | #include <sys/wait.h> |
| 28 | |
| 29 | #ifdef HAVE_CONFIG_H |
| 30 | #include <config.h> |
| 31 | #endif |
| 32 | #include <utils.h> |
| 33 | #include <log.h> |
| 34 | #include <req.h> |
| 35 | #include <proc.h> |
| 36 | #include <resp.h> |
| 37 | #include <cf.h> |
| 38 | |
| 39 | #define PAT_REST 0 |
| 40 | #define PAT_URL 1 |
| 41 | #define PAT_METHOD 2 |
| 42 | #define PAT_HEADER 3 |
| 43 | #define PAT_ALL 4 |
| 44 | #define PAT_DEFAULT 5 |
| 45 | |
| 46 | #define PATFL_MSS 1 |
| 47 | |
| 48 | struct config { |
| 49 | struct child *children; |
| 50 | struct pattern *patterns; |
| 51 | }; |
| 52 | |
| 53 | struct rule { |
| 54 | int type; |
| 55 | int fl; |
| 56 | char *header; |
| 57 | regex_t *pattern; |
| 58 | }; |
| 59 | |
| 60 | struct headmod { |
| 61 | struct headmod *next; |
| 62 | char *name, *value; |
| 63 | }; |
| 64 | |
| 65 | struct pattern { |
| 66 | struct pattern *next; |
| 67 | struct headmod *headers; |
| 68 | char *childnm; |
| 69 | struct rule **rules; |
| 70 | char *restpat; |
| 71 | }; |
| 72 | |
| 73 | static struct config *gconfig, *lconfig; |
| 74 | static volatile int reload = 0; |
| 75 | |
| 76 | static void freepattern(struct pattern *pat) |
| 77 | { |
| 78 | struct rule **rule; |
| 79 | struct headmod *head; |
| 80 | |
| 81 | for(rule = pat->rules; *rule; rule++) { |
| 82 | if((*rule)->header != NULL) |
| 83 | free((*rule)->header); |
| 84 | if((*rule)->pattern != NULL) { |
| 85 | regfree((*rule)->pattern); |
| 86 | free((*rule)->pattern); |
| 87 | } |
| 88 | free(*rule); |
| 89 | } |
| 90 | while((head = pat->headers) != NULL) { |
| 91 | pat->headers = head->next; |
| 92 | free(head->name); |
| 93 | free(head->value); |
| 94 | free(head); |
| 95 | } |
| 96 | if(pat->childnm != NULL) |
| 97 | free(pat->childnm); |
| 98 | free(pat); |
| 99 | } |
| 100 | |
| 101 | static void freeconfig(struct config *cf) |
| 102 | { |
| 103 | struct child *ch, *nch; |
| 104 | struct pattern *pat, *npat; |
| 105 | |
| 106 | for(ch = cf->children; ch != NULL; ch = nch) { |
| 107 | nch = ch->next; |
| 108 | freechild(ch); |
| 109 | } |
| 110 | for(pat = cf->patterns; pat != NULL; pat = npat) { |
| 111 | npat = pat->next; |
| 112 | freepattern(pat); |
| 113 | } |
| 114 | free(cf); |
| 115 | } |
| 116 | |
| 117 | static struct child *getchild(struct config *cf, char *name) |
| 118 | { |
| 119 | struct child *ch; |
| 120 | |
| 121 | for(ch = cf->children; ch; ch = ch->next) { |
| 122 | if(!strcmp(ch->name, name)) |
| 123 | break; |
| 124 | } |
| 125 | return(ch); |
| 126 | } |
| 127 | |
| 128 | static struct rule *newrule(struct pattern *pat) |
| 129 | { |
| 130 | int i; |
| 131 | struct rule *rule; |
| 132 | |
| 133 | for(i = 0; pat->rules[i]; i++); |
| 134 | pat->rules = srealloc(pat->rules, sizeof(*pat->rules) * (i + 2)); |
| 135 | rule = pat->rules[i] = szmalloc(sizeof(*rule)); |
| 136 | pat->rules[i + 1] = NULL; |
| 137 | return(rule); |
| 138 | } |
| 139 | |
| 140 | static struct pattern *newpattern(void) |
| 141 | { |
| 142 | struct pattern *pat; |
| 143 | |
| 144 | omalloc(pat); |
| 145 | pat->rules = szmalloc(sizeof(*pat->rules)); |
| 146 | return(pat); |
| 147 | } |
| 148 | |
| 149 | static regex_t *regalloc(char *regex, int flags) |
| 150 | { |
| 151 | regex_t *ret; |
| 152 | int res; |
| 153 | char errbuf[256]; |
| 154 | |
| 155 | omalloc(ret); |
| 156 | if((res = regcomp(ret, regex, flags | REG_EXTENDED)) != 0) { |
| 157 | regerror(res, ret, errbuf, sizeof(errbuf)); |
| 158 | flog(LOG_WARNING, "%s: %s", regex, errbuf); |
| 159 | free(ret); |
| 160 | return(NULL); |
| 161 | } |
| 162 | return(ret); |
| 163 | } |
| 164 | |
| 165 | static struct pattern *parsepattern(struct cfstate *s) |
| 166 | { |
| 167 | struct pattern *pat; |
| 168 | int sl; |
| 169 | struct rule *rule; |
| 170 | struct headmod *head; |
| 171 | regex_t *regex; |
| 172 | int rxfl; |
| 173 | |
| 174 | if(!strcmp(s->argv[0], "match")) { |
| 175 | s->expstart = 1; |
| 176 | pat = newpattern(); |
| 177 | } else { |
| 178 | return(NULL); |
| 179 | } |
| 180 | |
| 181 | sl = s->lno; |
| 182 | while(1) { |
| 183 | getcfline(s); |
| 184 | if(!strcmp(s->argv[0], "point") || |
| 185 | !strcmp(s->argv[0], "url") || |
| 186 | !strcmp(s->argv[0], "method")) { |
| 187 | if(s->argc < 2) { |
| 188 | flog(LOG_WARNING, "%s:%i: missing pattern for `%s' match", s->file, s->lno, s->argv[0]); |
| 189 | continue; |
| 190 | } |
| 191 | if(s->argc >= 3) { |
| 192 | if(strchr(s->argv[2], 'i')) |
| 193 | rxfl |= REG_ICASE; |
| 194 | } |
| 195 | if((regex = regalloc(s->argv[1], rxfl)) == NULL) { |
| 196 | flog(LOG_WARNING, "%s:%i: invalid regex for `%s' match", s->file, s->lno, s->argv[0]); |
| 197 | continue; |
| 198 | } |
| 199 | rule = newrule(pat); |
| 200 | if(!strcmp(s->argv[0], "point")) |
| 201 | rule->type = PAT_REST; |
| 202 | else if(!strcmp(s->argv[0], "url")) |
| 203 | rule->type = PAT_URL; |
| 204 | else if(!strcmp(s->argv[0], "method")) |
| 205 | rule->type = PAT_METHOD; |
| 206 | rule->pattern = regex; |
| 207 | if(s->argc >= 3) { |
| 208 | if(strchr(s->argv[2], 's')) |
| 209 | rule->fl |= PATFL_MSS; |
| 210 | } |
| 211 | } else if(!strcmp(s->argv[0], "header")) { |
| 212 | if(s->argc < 3) { |
| 213 | flog(LOG_WARNING, "%s:%i: missing header name or pattern for `header' match", s->file, s->lno); |
| 214 | continue; |
| 215 | } |
| 216 | if(s->argc >= 4) { |
| 217 | if(strchr(s->argv[3], 'i')) |
| 218 | rxfl |= REG_ICASE; |
| 219 | } |
| 220 | if((regex = regalloc(s->argv[2], rxfl)) == NULL) { |
| 221 | flog(LOG_WARNING, "%s:%i: invalid regex for `header' match", s->file, s->lno); |
| 222 | continue; |
| 223 | } |
| 224 | rule = newrule(pat); |
| 225 | rule->type = PAT_HEADER; |
| 226 | rule->header = sstrdup(s->argv[1]); |
| 227 | rule->pattern = regex; |
| 228 | if(s->argc >= 4) { |
| 229 | if(strchr(s->argv[3], 's')) |
| 230 | rule->fl |= PATFL_MSS; |
| 231 | } |
| 232 | } else if(!strcmp(s->argv[0], "all")) { |
| 233 | newrule(pat)->type = PAT_ALL; |
| 234 | } else if(!strcmp(s->argv[0], "default")) { |
| 235 | newrule(pat)->type = PAT_DEFAULT; |
| 236 | } else if(!strcmp(s->argv[0], "handler")) { |
| 237 | if(s->argc < 2) { |
| 238 | flog(LOG_WARNING, "%s:%i: missing child name for `handler' directive", s->file, s->lno); |
| 239 | continue; |
| 240 | } |
| 241 | if(pat->childnm != NULL) |
| 242 | free(pat->childnm); |
| 243 | pat->childnm = sstrdup(s->argv[1]); |
| 244 | } else if(!strcmp(s->argv[0], "restpat")) { |
| 245 | if(s->argc < 2) { |
| 246 | flog(LOG_WARNING, "%s:%i: missing pattern for `restpat' directive", s->file, s->lno); |
| 247 | continue; |
| 248 | } |
| 249 | if(pat->restpat != NULL) |
| 250 | free(pat->restpat); |
| 251 | pat->restpat = sstrdup(s->argv[1]); |
| 252 | } else if(!strcmp(s->argv[0], "set") || !strcmp(s->argv[0], "xset")) { |
| 253 | if(s->argc < 3) { |
| 254 | flog(LOG_WARNING, "%s:%i: missing header name or pattern for `%s' directive", s->file, s->lno, s->argv[0]); |
| 255 | continue; |
| 256 | } |
| 257 | omalloc(head); |
| 258 | if(!strcmp(s->argv[0], "xset")) |
| 259 | head->name = sprintf2("X-Ash-%s", s->argv[1]); |
| 260 | else |
| 261 | head->name = sstrdup(s->argv[1]); |
| 262 | head->value = sstrdup(s->argv[2]); |
| 263 | head->next = pat->headers; |
| 264 | pat->headers = head; |
| 265 | } else if(!strcmp(s->argv[0], "end") || !strcmp(s->argv[0], "eof")) { |
| 266 | break; |
| 267 | } else { |
| 268 | flog(LOG_WARNING, "%s:%i: unknown directive `%s' in pattern declaration", s->file, s->lno, s->argv[0]); |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | if(pat->rules[0] == NULL) { |
| 273 | flog(LOG_WARNING, "%s:%i: missing rules in match declaration", s->file, sl); |
| 274 | freepattern(pat); |
| 275 | return(NULL); |
| 276 | } |
| 277 | if(pat->childnm == NULL) { |
| 278 | flog(LOG_WARNING, "%s:%i: missing handler in match declaration", s->file, sl); |
| 279 | freepattern(pat); |
| 280 | return(NULL); |
| 281 | } |
| 282 | return(pat); |
| 283 | } |
| 284 | |
| 285 | static struct config *readconfig(char *filename) |
| 286 | { |
| 287 | struct cfstate *s; |
| 288 | struct config *cf; |
| 289 | struct child *ch; |
| 290 | struct pattern *pat; |
| 291 | FILE *in; |
| 292 | |
| 293 | if((in = fopen(filename, "r")) == NULL) { |
| 294 | flog(LOG_WARNING, "%s: %s", filename, strerror(errno)); |
| 295 | return(NULL); |
| 296 | } |
| 297 | s = mkcfparser(in, filename); |
| 298 | omalloc(cf); |
| 299 | |
| 300 | while(1) { |
| 301 | getcfline(s); |
| 302 | if((ch = parsechild(s)) != NULL) { |
| 303 | ch->next = cf->children; |
| 304 | cf->children = ch; |
| 305 | } else if((pat = parsepattern(s)) != NULL) { |
| 306 | pat->next = cf->patterns; |
| 307 | cf->patterns = pat; |
| 308 | } else if(!strcmp(s->argv[0], "eof")) { |
| 309 | break; |
| 310 | } else { |
| 311 | flog(LOG_WARNING, "%s:%i: unknown directive `%s'", s->file, s->lno, s->argv[0]); |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | freecfparser(s); |
| 316 | fclose(in); |
| 317 | return(cf); |
| 318 | } |
| 319 | |
| 320 | static void exprestpat(struct hthead *req, struct pattern *pat, char **mstr) |
| 321 | { |
| 322 | char *p, *p2, *hdr; |
| 323 | int mc; |
| 324 | struct charbuf buf; |
| 325 | |
| 326 | if(mstr == NULL) |
| 327 | mc = 0; |
| 328 | else |
| 329 | for(mc = 0; mstr[mc]; mc++); |
| 330 | bufinit(buf); |
| 331 | for(p = pat->restpat; *p; ) { |
| 332 | if(*p == '$') { |
| 333 | p++; |
| 334 | if((*p >= '0') && (*p <= '9')) { |
| 335 | if(*p - '0' < mc) |
| 336 | bufcatstr(buf, mstr[*p - '0']); |
| 337 | p++; |
| 338 | } else if(*p == '_') { |
| 339 | bufcatstr(buf, req->rest); |
| 340 | p++; |
| 341 | } else if(*p == '$') { |
| 342 | bufadd(buf, '$'); |
| 343 | p++; |
| 344 | } else if(*p == '{') { |
| 345 | if((p2 = strchr(p, '}')) == NULL) { |
| 346 | p++; |
| 347 | } else { |
| 348 | hdr = getheader(req, sprintf3("%.*s", p2 - p - 1, p + 1)); |
| 349 | if(hdr) |
| 350 | bufcatstr(buf, hdr); |
| 351 | } |
| 352 | } else if(!*p) { |
| 353 | } |
| 354 | } else { |
| 355 | bufadd(buf, *(p++)); |
| 356 | } |
| 357 | } |
| 358 | bufadd(buf, 0); |
| 359 | replrest(req, buf.b); |
| 360 | buffree(buf); |
| 361 | } |
| 362 | |
| 363 | static struct pattern *findmatch(struct config *cf, struct hthead *req, int trydefault) |
| 364 | { |
| 365 | int i, o; |
| 366 | struct pattern *pat; |
| 367 | struct rule *rule; |
| 368 | int rmo, matched; |
| 369 | char *pstr; |
| 370 | char **mstr; |
| 371 | regmatch_t gr[10]; |
| 372 | |
| 373 | mstr = NULL; |
| 374 | for(pat = cf->patterns; pat != NULL; pat = pat->next) { |
| 375 | rmo = -1; |
| 376 | for(i = 0; (rule = pat->rules[i]) != NULL; i++) { |
| 377 | matched = 0; |
| 378 | if(rule->type == PAT_REST) { |
| 379 | if((matched = !regexec(rule->pattern, pstr = req->rest, 10, gr, 0))) |
| 380 | rmo = gr[0].rm_eo; |
| 381 | else |
| 382 | break; |
| 383 | } else if(rule->type == PAT_URL) { |
| 384 | if(!(matched = !regexec(rule->pattern, pstr = req->url, 10, gr, 0))) |
| 385 | break; |
| 386 | } else if(rule->type == PAT_METHOD) { |
| 387 | if(!(matched = !regexec(rule->pattern, pstr = req->method, 10, gr, 0))) |
| 388 | break; |
| 389 | } else if(rule->type == PAT_HEADER) { |
| 390 | if(!(pstr = getheader(req, rule->header))) |
| 391 | break; |
| 392 | if(!(matched = !regexec(rule->pattern, pstr, 10, gr, 0))) |
| 393 | break; |
| 394 | } else if(rule->type == PAT_ALL) { |
| 395 | } else if(rule->type == PAT_DEFAULT) { |
| 396 | if(!trydefault) |
| 397 | break; |
| 398 | } |
| 399 | if(matched && (rule->fl & PATFL_MSS)) { |
| 400 | if(mstr) { |
| 401 | flog(LOG_WARNING, "two pattern rules marked with `s' flag found (for handler %s)", pat->childnm); |
| 402 | freeca(mstr); |
| 403 | } |
| 404 | for(o = 0; o < 10; o++) { |
| 405 | if(gr[o].rm_so < 0) |
| 406 | break; |
| 407 | } |
| 408 | mstr = szmalloc((o + 1) * sizeof(*mstr)); |
| 409 | for(o = 0; o < 10; o++) { |
| 410 | if(gr[o].rm_so < 0) |
| 411 | break; |
| 412 | mstr[o] = smalloc(gr[o].rm_eo - gr[o].rm_so + 1); |
| 413 | memcpy(mstr[o], pstr + gr[o].rm_so, gr[o].rm_eo - gr[o].rm_so); |
| 414 | mstr[o][gr[o].rm_eo - gr[o].rm_so] = 0; |
| 415 | } |
| 416 | } |
| 417 | } |
| 418 | if(!rule) { |
| 419 | if(pat->restpat) { |
| 420 | exprestpat(req, pat, mstr); |
| 421 | } else if(rmo != -1) { |
| 422 | replrest(req, req->rest + rmo); |
| 423 | } |
| 424 | if(mstr) |
| 425 | freeca(mstr); |
| 426 | return(pat); |
| 427 | } |
| 428 | if(mstr) { |
| 429 | freeca(mstr); |
| 430 | mstr = NULL; |
| 431 | } |
| 432 | } |
| 433 | return(NULL); |
| 434 | } |
| 435 | |
| 436 | static void serve(struct hthead *req, int fd) |
| 437 | { |
| 438 | struct pattern *pat; |
| 439 | struct headmod *head; |
| 440 | struct child *ch; |
| 441 | |
| 442 | pat = NULL; |
| 443 | if(pat == NULL) |
| 444 | pat = findmatch(lconfig, req, 0); |
| 445 | if(pat == NULL) |
| 446 | pat = findmatch(lconfig, req, 1); |
| 447 | if(gconfig != NULL) { |
| 448 | if(pat == NULL) |
| 449 | pat = findmatch(gconfig, req, 0); |
| 450 | if(pat == NULL) |
| 451 | pat = findmatch(gconfig, req, 1); |
| 452 | } |
| 453 | if(pat == NULL) { |
| 454 | simpleerror(fd, 404, "Not Found", "The requested resource could not be found on this server."); |
| 455 | return; |
| 456 | } |
| 457 | ch = NULL; |
| 458 | if(ch == NULL) |
| 459 | ch = getchild(lconfig, pat->childnm); |
| 460 | if(gconfig != NULL) { |
| 461 | if(ch == NULL) |
| 462 | ch = getchild(gconfig, pat->childnm); |
| 463 | } |
| 464 | if(ch == NULL) { |
| 465 | flog(LOG_ERR, "child %s requested, but was not declared", pat->childnm); |
| 466 | simpleerror(fd, 500, "Configuration Error", "The server is erroneously configured. Handler %s was requested, but not declared.", pat->childnm); |
| 467 | return; |
| 468 | } |
| 469 | |
| 470 | for(head = pat->headers; head != NULL; head = head->next) { |
| 471 | headrmheader(req, head->name); |
| 472 | headappheader(req, head->name, head->value); |
| 473 | } |
| 474 | if(childhandle(ch, req, fd, NULL, NULL)) |
| 475 | simpleerror(fd, 500, "Server Error", "The request handler crashed."); |
| 476 | } |
| 477 | |
| 478 | static void reloadconf(char *nm) |
| 479 | { |
| 480 | struct config *cf; |
| 481 | |
| 482 | if((cf = readconfig(nm)) == NULL) { |
| 483 | flog(LOG_WARNING, "could not reload configuration file `%s'", nm); |
| 484 | return; |
| 485 | } |
| 486 | mergechildren(cf->children, lconfig->children); |
| 487 | freeconfig(lconfig); |
| 488 | lconfig = cf; |
| 489 | } |
| 490 | |
| 491 | static void chldhandler(int sig) |
| 492 | { |
| 493 | pid_t pid; |
| 494 | int st; |
| 495 | |
| 496 | while((pid = waitpid(-1, &st, WNOHANG)) > 0) { |
| 497 | if(WCOREDUMP(st)) |
| 498 | flog(LOG_WARNING, "child process %i dumped core", pid); |
| 499 | } |
| 500 | } |
| 501 | |
| 502 | static void sighandler(int sig) |
| 503 | { |
| 504 | if(sig == SIGHUP) |
| 505 | reload = 1; |
| 506 | } |
| 507 | |
| 508 | static void usage(FILE *out) |
| 509 | { |
| 510 | fprintf(out, "usage: patplex [-hN] CONFIGFILE\n"); |
| 511 | } |
| 512 | |
| 513 | int main(int argc, char **argv) |
| 514 | { |
| 515 | int c; |
| 516 | int nodef; |
| 517 | char *gcf; |
| 518 | struct hthead *req; |
| 519 | int fd; |
| 520 | |
| 521 | nodef = 0; |
| 522 | while((c = getopt(argc, argv, "hN")) >= 0) { |
| 523 | switch(c) { |
| 524 | case 'h': |
| 525 | usage(stdout); |
| 526 | exit(0); |
| 527 | case 'N': |
| 528 | nodef = 1; |
| 529 | break; |
| 530 | default: |
| 531 | usage(stderr); |
| 532 | exit(1); |
| 533 | } |
| 534 | } |
| 535 | if(argc - optind < 1) { |
| 536 | usage(stderr); |
| 537 | exit(1); |
| 538 | } |
| 539 | if(!nodef) { |
| 540 | if((gcf = findstdconf("ashd/patplex.rc")) != NULL) { |
| 541 | gconfig = readconfig(gcf); |
| 542 | free(gcf); |
| 543 | } |
| 544 | } |
| 545 | if((lconfig = readconfig(argv[optind])) == NULL) { |
| 546 | flog(LOG_ERR, "could not read `%s'", argv[optind]); |
| 547 | exit(1); |
| 548 | } |
| 549 | signal(SIGCHLD, chldhandler); |
| 550 | signal(SIGHUP, sighandler); |
| 551 | signal(SIGPIPE, sighandler); |
| 552 | while(1) { |
| 553 | if(reload) { |
| 554 | reloadconf(argv[optind]); |
| 555 | reload = 0; |
| 556 | } |
| 557 | if((fd = recvreq(0, &req)) < 0) { |
| 558 | if(errno == EINTR) |
| 559 | continue; |
| 560 | if(errno != 0) |
| 561 | flog(LOG_ERR, "recvreq: %s", strerror(errno)); |
| 562 | break; |
| 563 | } |
| 564 | serve(req, fd); |
| 565 | freehthead(req); |
| 566 | close(fd); |
| 567 | } |
| 568 | return(0); |
| 569 | } |