| 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 | |
| 28 | #ifdef HAVE_CONFIG_H |
| 29 | #include <config.h> |
| 30 | #endif |
| 31 | #include <utils.h> |
| 32 | #include <log.h> |
| 33 | #include <req.h> |
| 34 | #include <proc.h> |
| 35 | #include <resp.h> |
| 36 | |
| 37 | #define CH_SOCKET 0 |
| 38 | #define CH_FORK 1 |
| 39 | |
| 40 | #define PAT_REST 0 |
| 41 | #define PAT_URL 1 |
| 42 | #define PAT_METHOD 2 |
| 43 | #define PAT_HEADER 3 |
| 44 | #define PAT_ALL 4 |
| 45 | #define PAT_DEFAULT 5 |
| 46 | |
| 47 | #define PATFL_MSS 1 |
| 48 | |
| 49 | struct config { |
| 50 | struct child *children; |
| 51 | struct pattern *patterns; |
| 52 | }; |
| 53 | |
| 54 | struct child { |
| 55 | struct child *next; |
| 56 | char *name; |
| 57 | int type; |
| 58 | char **argv; |
| 59 | int fd; |
| 60 | }; |
| 61 | |
| 62 | struct rule { |
| 63 | int type; |
| 64 | int fl; |
| 65 | char *header; |
| 66 | regex_t *pattern; |
| 67 | }; |
| 68 | |
| 69 | struct pattern { |
| 70 | struct pattern *next; |
| 71 | char *childnm; |
| 72 | struct rule **rules; |
| 73 | char *restpat; |
| 74 | }; |
| 75 | |
| 76 | static struct config *config; |
| 77 | |
| 78 | static void freepattern(struct pattern *pat) |
| 79 | { |
| 80 | struct rule **rule; |
| 81 | |
| 82 | for(rule = pat->rules; *rule; rule++) { |
| 83 | if((*rule)->header != NULL) |
| 84 | free((*rule)->header); |
| 85 | if((*rule)->pattern != NULL) { |
| 86 | regfree((*rule)->pattern); |
| 87 | free((*rule)->pattern); |
| 88 | } |
| 89 | free(*rule); |
| 90 | } |
| 91 | if(pat->childnm != NULL) |
| 92 | free(pat->childnm); |
| 93 | free(pat); |
| 94 | } |
| 95 | |
| 96 | static void freechild(struct child *ch) |
| 97 | { |
| 98 | if(ch->fd != -1) |
| 99 | close(ch->fd); |
| 100 | if(ch->name != NULL) |
| 101 | free(ch->name); |
| 102 | if(ch->argv != NULL) |
| 103 | freeca(ch->argv); |
| 104 | free(ch); |
| 105 | } |
| 106 | |
| 107 | static struct child *newchild(char *name, int type) |
| 108 | { |
| 109 | struct child *ch; |
| 110 | |
| 111 | omalloc(ch); |
| 112 | ch->name = sstrdup(name); |
| 113 | ch->type = type; |
| 114 | ch->fd = -1; |
| 115 | return(ch); |
| 116 | } |
| 117 | |
| 118 | static struct child *getchild(struct config *cf, char *name) |
| 119 | { |
| 120 | struct child *ch; |
| 121 | |
| 122 | for(ch = cf->children; ch; ch = ch->next) { |
| 123 | if(!strcmp(ch->name, name)) |
| 124 | break; |
| 125 | } |
| 126 | return(ch); |
| 127 | } |
| 128 | |
| 129 | static struct rule *newrule(struct pattern *pat) |
| 130 | { |
| 131 | int i; |
| 132 | struct rule *rule; |
| 133 | |
| 134 | for(i = 0; pat->rules[i]; i++); |
| 135 | pat->rules = srealloc(pat->rules, sizeof(*pat->rules) * (i + 2)); |
| 136 | rule = pat->rules[i] = szmalloc(sizeof(*rule)); |
| 137 | pat->rules[i + 1] = NULL; |
| 138 | return(rule); |
| 139 | } |
| 140 | |
| 141 | static struct pattern *newpattern(void) |
| 142 | { |
| 143 | struct pattern *pat; |
| 144 | |
| 145 | omalloc(pat); |
| 146 | pat->rules = szmalloc(sizeof(*pat->rules)); |
| 147 | return(pat); |
| 148 | } |
| 149 | |
| 150 | static regex_t *regalloc(char *regex, int flags) |
| 151 | { |
| 152 | regex_t *ret; |
| 153 | int res; |
| 154 | char errbuf[256]; |
| 155 | |
| 156 | omalloc(ret); |
| 157 | if((res = regcomp(ret, regex, flags | REG_EXTENDED)) != 0) { |
| 158 | regerror(res, ret, errbuf, sizeof(errbuf)); |
| 159 | flog(LOG_WARNING, "%s: %s", regex, errbuf); |
| 160 | free(ret); |
| 161 | return(NULL); |
| 162 | } |
| 163 | return(ret); |
| 164 | } |
| 165 | |
| 166 | static struct config *readconfig(char *filename) |
| 167 | { |
| 168 | int i; |
| 169 | struct config *cf; |
| 170 | FILE *s; |
| 171 | char line[1024]; |
| 172 | char *p, **w; |
| 173 | int ind, eof; |
| 174 | int lno; |
| 175 | int state; |
| 176 | int rv; |
| 177 | int argc; |
| 178 | struct child *child; |
| 179 | struct pattern *pat; |
| 180 | struct rule *rule; |
| 181 | regex_t *regex; |
| 182 | int rxfl; |
| 183 | |
| 184 | if((s = fopen(filename, "r")) == NULL) |
| 185 | return(NULL); |
| 186 | omalloc(cf); |
| 187 | eof = 0; |
| 188 | state = 0; |
| 189 | w = NULL; |
| 190 | lno = 0; |
| 191 | do { |
| 192 | if(fgets(line, sizeof(line), s) == NULL) { |
| 193 | eof = 1; |
| 194 | line[0] = 0; |
| 195 | } |
| 196 | lno++; |
| 197 | for(p = line; *p; p++) { |
| 198 | if(*p == '#') |
| 199 | continue; |
| 200 | if(!isspace(*p)) |
| 201 | break; |
| 202 | } |
| 203 | ind = isspace(line[0]); |
| 204 | w = tokenize(line); |
| 205 | argc = calen(w); |
| 206 | |
| 207 | retry: |
| 208 | if(state == 0) { |
| 209 | if(ind) { |
| 210 | flog(LOG_WARNING, "%s%i: unexpected line indentation in global scope", filename, lno); |
| 211 | goto next; |
| 212 | } else { |
| 213 | if(!w[0]) { |
| 214 | } else if(!strcmp(w[0], "child")) { |
| 215 | if(argc < 2) { |
| 216 | flog(LOG_WARNING, "%s:%i: missing name in child declaration", filename, lno); |
| 217 | goto next; |
| 218 | } |
| 219 | child = newchild(w[1], CH_SOCKET); |
| 220 | state = 1; |
| 221 | } else if(!strcmp(w[0], "fchild")) { |
| 222 | if(argc < 2) { |
| 223 | flog(LOG_WARNING, "%s:%i: missing name in child declaration", filename, lno); |
| 224 | goto next; |
| 225 | } |
| 226 | child = newchild(w[1], CH_FORK); |
| 227 | state = 1; |
| 228 | } else if(!strcmp(w[0], "match")) { |
| 229 | pat = newpattern(); |
| 230 | state = 2; |
| 231 | } else { |
| 232 | flog(LOG_WARNING, "%s:%i: unknown directive %s", filename, lno, w[0]); |
| 233 | } |
| 234 | } |
| 235 | } else if(state == 1) { |
| 236 | if(ind) { |
| 237 | if(!w[0]) { |
| 238 | } else if(!strcmp(w[0], "exec")) { |
| 239 | if(argc < 2) { |
| 240 | flog(LOG_WARNING, "%s:%i: too few parameters to `exec'", filename, lno); |
| 241 | goto next; |
| 242 | } |
| 243 | child->argv = szmalloc(sizeof(*child->argv) * argc); |
| 244 | for(i = 0; i < argc - 1; i++) |
| 245 | child->argv[i] = sstrdup(w[i + 1]); |
| 246 | } else { |
| 247 | flog(LOG_WARNING, "%s:%i: unknown directive %s", filename, lno, w[0]); |
| 248 | } |
| 249 | } else { |
| 250 | state = 0; |
| 251 | if(child->argv == NULL) { |
| 252 | flog(LOG_WARNING, "%s:%i: missing `exec' in child declaration %s", filename, lno, child->name); |
| 253 | freechild(child); |
| 254 | goto retry; |
| 255 | } |
| 256 | child->next = cf->children; |
| 257 | cf->children = child; |
| 258 | goto retry; |
| 259 | } |
| 260 | } else if(state == 2) { |
| 261 | if(ind) { |
| 262 | rxfl = 0; |
| 263 | if(!w[0]) { |
| 264 | } else if(!strcmp(w[0], "point") || |
| 265 | !strcmp(w[0], "url") || |
| 266 | !strcmp(w[0], "method")) { |
| 267 | if(argc < 2) { |
| 268 | flog(LOG_WARNING, "%s:%i: missing pattern for `%s' match", w[0], filename, lno); |
| 269 | goto next; |
| 270 | } |
| 271 | if(argc >= 3) { |
| 272 | if(strchr(w[2], 'i')) |
| 273 | rxfl |= REG_ICASE; |
| 274 | } |
| 275 | if((regex = regalloc(w[1], rxfl)) == NULL) { |
| 276 | flog(LOG_WARNING, "%s:%i: invalid regex for `%s' match", w[0], filename, lno); |
| 277 | goto next; |
| 278 | } |
| 279 | rule = newrule(pat); |
| 280 | if(!strcmp(w[0], "point")) |
| 281 | rule->type = PAT_REST; |
| 282 | else if(!strcmp(w[0], "url")) |
| 283 | rule->type = PAT_URL; |
| 284 | else if(!strcmp(w[0], "method")) |
| 285 | rule->type = PAT_METHOD; |
| 286 | rule->pattern = regex; |
| 287 | if(argc >= 3) { |
| 288 | if(strchr(w[2], 's')) |
| 289 | rule->fl |= PATFL_MSS; |
| 290 | } |
| 291 | } else if(!strcmp(w[0], "header")) { |
| 292 | if(argc < 3) { |
| 293 | flog(LOG_WARNING, "%s:%i: missing header name or pattern for `header' match", filename, lno); |
| 294 | goto next; |
| 295 | } |
| 296 | if(argc >= 4) { |
| 297 | if(strchr(w[3], 'i')) |
| 298 | rxfl |= REG_ICASE; |
| 299 | } |
| 300 | if((regex = regalloc(w[2], rxfl)) == NULL) { |
| 301 | flog(LOG_WARNING, "%s:%i: invalid regex for `header' match", filename, lno); |
| 302 | goto next; |
| 303 | } |
| 304 | rule = newrule(pat); |
| 305 | rule->type = PAT_HEADER; |
| 306 | rule->header = sstrdup(w[1]); |
| 307 | rule->pattern = regex; |
| 308 | if(argc >= 4) { |
| 309 | if(strchr(w[3], 's')) |
| 310 | rule->fl |= PATFL_MSS; |
| 311 | } |
| 312 | } else if(!strcmp(w[0], "all")) { |
| 313 | newrule(pat)->type = PAT_ALL; |
| 314 | } else if(!strcmp(w[0], "default")) { |
| 315 | newrule(pat)->type = PAT_DEFAULT; |
| 316 | } else if(!strcmp(w[0], "handler")) { |
| 317 | if(argc < 2) { |
| 318 | flog(LOG_WARNING, "%s:%i: missing child name for `handler' directive", filename, lno); |
| 319 | goto next; |
| 320 | } |
| 321 | if(pat->childnm != NULL) |
| 322 | free(pat->childnm); |
| 323 | pat->childnm = sstrdup(w[1]); |
| 324 | } else if(!strcmp(w[0], "restpat")) { |
| 325 | if(argc < 2) { |
| 326 | flog(LOG_WARNING, "%s:%i: missing pattern for `restpat' directive", filename, lno); |
| 327 | goto next; |
| 328 | } |
| 329 | if(pat->restpat != NULL) |
| 330 | free(pat->restpat); |
| 331 | pat->restpat = sstrdup(w[1]); |
| 332 | } else { |
| 333 | flog(LOG_WARNING, "%s:%i: unknown directive %s", filename, lno, w[0]); |
| 334 | } |
| 335 | } else { |
| 336 | state = 0; |
| 337 | if(pat->rules[0] == NULL) { |
| 338 | flog(LOG_WARNING, "%s:%i: missing rules in match declaration", filename, lno); |
| 339 | freepattern(pat); |
| 340 | goto retry; |
| 341 | } |
| 342 | if(pat->childnm == NULL) { |
| 343 | flog(LOG_WARNING, "%s:%i: missing handler in match declaration", filename, lno); |
| 344 | freepattern(pat); |
| 345 | goto retry; |
| 346 | } |
| 347 | pat->next = cf->patterns; |
| 348 | cf->patterns = pat; |
| 349 | goto retry; |
| 350 | } |
| 351 | } |
| 352 | |
| 353 | next: |
| 354 | freeca(w); |
| 355 | w = NULL; |
| 356 | } while(!eof); |
| 357 | rv = 0; |
| 358 | |
| 359 | if(w != NULL) |
| 360 | freeca(w); |
| 361 | fclose(s); |
| 362 | return(cf); |
| 363 | } |
| 364 | |
| 365 | static void exprestpat(struct hthead *req, struct pattern *pat, char **mstr) |
| 366 | { |
| 367 | char *p, *p2, *hdr; |
| 368 | int mc; |
| 369 | struct charbuf buf; |
| 370 | |
| 371 | if(mstr == NULL) |
| 372 | mc = 0; |
| 373 | else |
| 374 | for(mc = 0; mstr[mc]; mc++); |
| 375 | bufinit(buf); |
| 376 | for(p = pat->restpat; *p; ) { |
| 377 | if(*p == '$') { |
| 378 | p++; |
| 379 | if((*p >= '0') && (*p <= '9')) { |
| 380 | if(*p - '0' < mc) |
| 381 | bufcatstr(buf, mstr[*p - '0']); |
| 382 | p++; |
| 383 | } else if(*p == '_') { |
| 384 | bufcatstr(buf, req->rest); |
| 385 | p++; |
| 386 | } else if(*p == '$') { |
| 387 | bufadd(buf, '$'); |
| 388 | p++; |
| 389 | } else if(*p == '{') { |
| 390 | if((p2 = strchr(p, '{')) == NULL) { |
| 391 | p++; |
| 392 | } else { |
| 393 | hdr = getheader(req, sprintf3("$.*s", p2 - p - 1, p + 1)); |
| 394 | if(hdr) |
| 395 | bufcatstr(buf, hdr); |
| 396 | } |
| 397 | } else if(!*p) { |
| 398 | } |
| 399 | } else { |
| 400 | bufadd(buf, *(p++)); |
| 401 | } |
| 402 | } |
| 403 | bufadd(buf, 0); |
| 404 | replrest(req, buf.b); |
| 405 | buffree(buf); |
| 406 | } |
| 407 | |
| 408 | static char *findmatch(struct config *cf, struct hthead *req, int trydefault) |
| 409 | { |
| 410 | int i, o; |
| 411 | struct pattern *pat; |
| 412 | struct rule *rule; |
| 413 | int rmo, matched; |
| 414 | char *pstr; |
| 415 | char **mstr; |
| 416 | regmatch_t gr[10]; |
| 417 | |
| 418 | mstr = NULL; |
| 419 | for(pat = cf->patterns; pat != NULL; pat = pat->next) { |
| 420 | rmo = -1; |
| 421 | for(i = 0; (rule = pat->rules[i]) != NULL; i++) { |
| 422 | matched = 0; |
| 423 | if(rule->type == PAT_REST) { |
| 424 | if((matched = !regexec(rule->pattern, pstr = req->rest, 10, gr, 0))) |
| 425 | rmo = gr[0].rm_eo; |
| 426 | else |
| 427 | break; |
| 428 | } else if(rule->type == PAT_URL) { |
| 429 | if(!(matched = !regexec(rule->pattern, pstr = req->url, 10, gr, 0))) |
| 430 | break; |
| 431 | } else if(rule->type == PAT_METHOD) { |
| 432 | if(!(matched = !regexec(rule->pattern, pstr = req->method, 10, gr, 0))) |
| 433 | break; |
| 434 | } else if(rule->type == PAT_HEADER) { |
| 435 | if(!(pstr = getheader(req, rule->header))) |
| 436 | break; |
| 437 | if(!(matched = !regexec(rule->pattern, pstr, 10, gr, 0))) |
| 438 | break; |
| 439 | } else if(rule->type == PAT_ALL) { |
| 440 | } else if(rule->type == PAT_DEFAULT) { |
| 441 | if(!trydefault) |
| 442 | break; |
| 443 | } |
| 444 | if(matched && (rule->fl & PATFL_MSS)) { |
| 445 | if(mstr) { |
| 446 | flog(LOG_WARNING, "two pattern rules marked with `s' flag found (for handler %s)", pat->childnm); |
| 447 | freeca(mstr); |
| 448 | } |
| 449 | for(o = 0; o < 10; o++) { |
| 450 | if(gr[o].rm_so < 0) |
| 451 | break; |
| 452 | } |
| 453 | mstr = szmalloc((o + 1) * sizeof(*mstr)); |
| 454 | for(o = 0; o < 10; o++) { |
| 455 | if(gr[o].rm_so < 0) |
| 456 | break; |
| 457 | mstr[o] = smalloc(gr[o].rm_eo - gr[o].rm_so + 1); |
| 458 | memcpy(mstr[o], pstr + gr[o].rm_so, gr[o].rm_eo - gr[o].rm_so); |
| 459 | mstr[o][gr[o].rm_eo - gr[o].rm_so] = 0; |
| 460 | } |
| 461 | } |
| 462 | } |
| 463 | if(!rule) { |
| 464 | if(pat->restpat) { |
| 465 | exprestpat(req, pat, mstr); |
| 466 | } else if(rmo != -1) { |
| 467 | replrest(req, req->rest + rmo); |
| 468 | } |
| 469 | if(mstr) |
| 470 | freeca(mstr); |
| 471 | return(pat->childnm); |
| 472 | } |
| 473 | if(mstr) { |
| 474 | freeca(mstr); |
| 475 | mstr = NULL; |
| 476 | } |
| 477 | } |
| 478 | return(NULL); |
| 479 | } |
| 480 | |
| 481 | static void forkchild(struct child *ch) |
| 482 | { |
| 483 | ch->fd = stdmkchild(ch->argv); |
| 484 | } |
| 485 | |
| 486 | static void passreq(struct child *ch, struct hthead *req, int fd) |
| 487 | { |
| 488 | if(ch->fd < 0) |
| 489 | forkchild(ch); |
| 490 | if(sendreq(ch->fd, req, fd)) { |
| 491 | if(errno == EPIPE) { |
| 492 | /* Assume that the child has crashed and restart it. */ |
| 493 | forkchild(ch); |
| 494 | if(!sendreq(ch->fd, req, fd)) |
| 495 | return; |
| 496 | } |
| 497 | flog(LOG_ERR, "could not pass on request to child %s: %s", ch->name, strerror(errno)); |
| 498 | close(ch->fd); |
| 499 | ch->fd = -1; |
| 500 | } |
| 501 | } |
| 502 | |
| 503 | static void serve(struct hthead *req, int fd) |
| 504 | { |
| 505 | char *chnm; |
| 506 | struct child *ch; |
| 507 | |
| 508 | if(((chnm = findmatch(config, req, 0)) == NULL) && ((chnm = findmatch(config, req, 1)) == NULL)) { |
| 509 | simpleerror(fd, 404, "Not Found", "The requested resource could not be found on this server."); |
| 510 | return; |
| 511 | } |
| 512 | if((ch = getchild(config, chnm)) == NULL) { |
| 513 | flog(LOG_ERR, "child %s requested, but was not declared", chnm); |
| 514 | simpleerror(fd, 500, "Configuration Error", "The server is erroneously configured. Handler %s was requested, but not declared.", chnm); |
| 515 | return; |
| 516 | } |
| 517 | |
| 518 | if(ch->type == CH_SOCKET) { |
| 519 | passreq(ch, req, fd); |
| 520 | } else if(ch->type == CH_FORK) { |
| 521 | stdforkserve(ch->argv, req, fd); |
| 522 | } |
| 523 | } |
| 524 | |
| 525 | int main(int argc, char **argv) |
| 526 | { |
| 527 | struct hthead *req; |
| 528 | int fd; |
| 529 | |
| 530 | if(argc < 2) { |
| 531 | flog(LOG_ERR, "usage: patplex CONFIGFILE"); |
| 532 | exit(1); |
| 533 | } |
| 534 | config = readconfig(argv[1]); |
| 535 | signal(SIGCHLD, SIG_IGN); |
| 536 | while(1) { |
| 537 | if((fd = recvreq(0, &req)) < 0) { |
| 538 | if(errno != 0) |
| 539 | flog(LOG_ERR, "recvreq: %s", strerror(errno)); |
| 540 | break; |
| 541 | } |
| 542 | serve(req, fd); |
| 543 | freehthead(req); |
| 544 | close(fd); |
| 545 | } |
| 546 | return(0); |
| 547 | } |