| 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 <errno.h> |
| 24 | #include <sys/stat.h> |
| 25 | #include <ctype.h> |
| 26 | #include <dirent.h> |
| 27 | #include <time.h> |
| 28 | #include <fnmatch.h> |
| 29 | #include <sys/wait.h> |
| 30 | #include <sys/signal.h> |
| 31 | |
| 32 | #ifdef HAVE_CONFIG_H |
| 33 | #include <config.h> |
| 34 | #endif |
| 35 | #include <utils.h> |
| 36 | #include <log.h> |
| 37 | #include <req.h> |
| 38 | #include <proc.h> |
| 39 | #include <resp.h> |
| 40 | #include <cf.h> |
| 41 | |
| 42 | #include "dirplex.h" |
| 43 | |
| 44 | time_t now; |
| 45 | |
| 46 | static void chinit(void *idata) |
| 47 | { |
| 48 | char *twd = idata; |
| 49 | |
| 50 | if(twd != NULL) { |
| 51 | /* This should never be able to fail other than for critical |
| 52 | * I/O errors or some such, since the path has already been |
| 53 | * traversed. */ |
| 54 | if(chdir(twd)) |
| 55 | exit(127); |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | static void childerror(struct hthead *req, int fd) |
| 60 | { |
| 61 | if(errno == EAGAIN) |
| 62 | simpleerror(fd, 500, "Server Error", "The request handler is overloaded."); |
| 63 | else |
| 64 | simpleerror(fd, 500, "Server Error", "The request handler crashed."); |
| 65 | } |
| 66 | |
| 67 | static void handle(struct hthead *req, int fd, char *path, struct pattern *pat) |
| 68 | { |
| 69 | struct child *ch; |
| 70 | struct config *ccf; |
| 71 | struct headmod *head; |
| 72 | char *twd; |
| 73 | |
| 74 | for(head = pat->headers; head != NULL; head = head->next) { |
| 75 | headrmheader(req, head->name); |
| 76 | headappheader(req, head->name, head->value); |
| 77 | } |
| 78 | if(!strncmp(path, "./", 2) && path[2]) |
| 79 | path += 2; |
| 80 | if(pat->fchild) { |
| 81 | headappheader(req, "X-Ash-File", path); |
| 82 | stdforkserve(pat->fchild, req, fd, NULL, NULL); |
| 83 | } else { |
| 84 | if((ch = findchild(path, pat->childnm, &ccf)) == NULL) { |
| 85 | flog(LOG_ERR, "child %s requested, but was not declared", pat->childnm); |
| 86 | simpleerror(fd, 500, "Configuration Error", "The server is erroneously configured. Handler %s was requested, but not declared.", pat->childnm); |
| 87 | return; |
| 88 | } |
| 89 | if((twd = ccf?ccf->path:NULL) != NULL) { |
| 90 | if(!strcmp(twd, ".")) { |
| 91 | twd = NULL; |
| 92 | } else if(strncmp(path, twd, strlen(twd)) || (path[strlen(twd)] != '/')) { |
| 93 | /* Should be an impossible case under the current (and |
| 94 | * foreseeable) scheme. */ |
| 95 | simpleerror(fd, 500, "Server Error", "An internal server error occurred."); |
| 96 | return; |
| 97 | } else { |
| 98 | path = path + strlen(twd) + 1; |
| 99 | } |
| 100 | } |
| 101 | headappheader(req, "X-Ash-File", path); |
| 102 | if(childhandle(ch, req, fd, chinit, twd)) |
| 103 | childerror(req, fd); |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | static void handle404(struct hthead *req, int fd, char *path) |
| 108 | { |
| 109 | struct child *ch; |
| 110 | struct config *ccf; |
| 111 | struct pattern *pat; |
| 112 | |
| 113 | char tmp[strlen(path) + 1]; |
| 114 | strcpy(tmp, path); |
| 115 | if((pat = findmatch(tmp, 0, PT_NOTFOUND)) != NULL) { |
| 116 | handle(req, fd, tmp, pat); |
| 117 | } else { |
| 118 | ch = findchild(tmp, ".notfound", &ccf); |
| 119 | if(childhandle(ch, req, fd, chinit, ccf?ccf->path:NULL)) |
| 120 | childerror(req, fd); |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | static void handlefile(struct hthead *req, int fd, char *path) |
| 125 | { |
| 126 | struct pattern *pat; |
| 127 | |
| 128 | if((pat = findmatch(path, 0, PT_FILE)) == NULL) { |
| 129 | handle404(req, fd, path); |
| 130 | return; |
| 131 | } |
| 132 | handle(req, fd, path, pat); |
| 133 | } |
| 134 | |
| 135 | static int checkaccess(char *path, char *name) |
| 136 | { |
| 137 | int i, o; |
| 138 | struct config **cfs; |
| 139 | |
| 140 | if(*name == '.') { |
| 141 | cfs = getconfigs(sprintf3("%s/", path)); |
| 142 | for(i = 0; cfs[i] != NULL; i++) { |
| 143 | if(cfs[i]->dotallow != NULL) { |
| 144 | for(o = 0; cfs[i]->dotallow[o] != NULL; o++) { |
| 145 | if(!fnmatch(cfs[i]->dotallow[o], name, 0)) |
| 146 | return(1); |
| 147 | } |
| 148 | break; |
| 149 | } |
| 150 | } |
| 151 | return(0); |
| 152 | } |
| 153 | return(1); |
| 154 | } |
| 155 | |
| 156 | static char *findfile(char *path, char *name, struct stat *sb) |
| 157 | { |
| 158 | DIR *dir; |
| 159 | struct stat sbuf; |
| 160 | struct dirent *dent; |
| 161 | char *p, *fp, *ret; |
| 162 | |
| 163 | if(sb == NULL) |
| 164 | sb = &sbuf; |
| 165 | if((dir = opendir(path)) == NULL) |
| 166 | return(NULL); |
| 167 | ret = NULL; |
| 168 | while((dent = readdir(dir)) != NULL) { |
| 169 | /* Ignore backup files. |
| 170 | * XXX: There is probably a better and more extensible way to |
| 171 | * do this. */ |
| 172 | if(dent->d_name[strlen(dent->d_name) - 1] == '~') |
| 173 | continue; |
| 174 | if((p = strchr(dent->d_name, '.')) == NULL) |
| 175 | continue; |
| 176 | if(p - dent->d_name != strlen(name)) |
| 177 | continue; |
| 178 | if(strncmp(dent->d_name, name, strlen(name))) |
| 179 | continue; |
| 180 | fp = sprintf2("%s/%s", path, dent->d_name); |
| 181 | if(stat(fp, sb)) { |
| 182 | free(fp); |
| 183 | continue; |
| 184 | } |
| 185 | if(!S_ISREG(sb->st_mode)) { |
| 186 | free(fp); |
| 187 | continue; |
| 188 | } |
| 189 | if(!checkaccess(path, dent->d_name)) { |
| 190 | free(fp); |
| 191 | continue; |
| 192 | } |
| 193 | ret = fp; |
| 194 | break; |
| 195 | } |
| 196 | closedir(dir); |
| 197 | return(ret); |
| 198 | } |
| 199 | |
| 200 | static void handledir(struct hthead *req, int fd, char *path) |
| 201 | { |
| 202 | struct config **cfs; |
| 203 | int i, o; |
| 204 | struct stat sb; |
| 205 | char *inm, *ipath, *cpath; |
| 206 | struct pattern *pat; |
| 207 | |
| 208 | cpath = sprintf2("%s/", path); |
| 209 | cfs = getconfigs(cpath); |
| 210 | for(i = 0; cfs[i] != NULL; i++) { |
| 211 | if(cfs[i]->index != NULL) { |
| 212 | for(o = 0; cfs[i]->index[o] != NULL; o++) { |
| 213 | inm = cfs[i]->index[o]; |
| 214 | ipath = sprintf2("%s/%s", path, inm); |
| 215 | if(!stat(ipath, &sb) && S_ISREG(sb.st_mode)) { |
| 216 | handlefile(req, fd, ipath); |
| 217 | free(ipath); |
| 218 | goto out; |
| 219 | } |
| 220 | free(ipath); |
| 221 | |
| 222 | if(!strchr(inm, '.') && ((ipath = findfile(path, inm, NULL)) != NULL)) { |
| 223 | handlefile(req, fd, ipath); |
| 224 | free(ipath); |
| 225 | goto out; |
| 226 | } |
| 227 | } |
| 228 | break; |
| 229 | } |
| 230 | } |
| 231 | if((pat = findmatch(cpath, 0, PT_DIR)) != NULL) { |
| 232 | handle(req, fd, cpath, pat); |
| 233 | goto out; |
| 234 | } |
| 235 | simpleerror(fd, 403, "Not Authorized", "Will not send listings for this directory."); |
| 236 | |
| 237 | out: |
| 238 | free(cpath); |
| 239 | } |
| 240 | |
| 241 | static int checkpath(struct hthead *req, int fd, char *path, char *rest, int final); |
| 242 | |
| 243 | static int checkentry(struct hthead *req, int fd, char *path, char *rest, char *el, int final) |
| 244 | { |
| 245 | struct stat sb; |
| 246 | char *newpath; |
| 247 | int rv; |
| 248 | |
| 249 | if(!stat(sprintf3("%s/%s", path, el), &sb)) { |
| 250 | if(!checkaccess(path, el)) |
| 251 | return(0); |
| 252 | if(S_ISDIR(sb.st_mode)) { |
| 253 | if(!*rest) { |
| 254 | stdredir(req, fd, 301, sprintf3("%s/", el)); |
| 255 | return(1); |
| 256 | } |
| 257 | newpath = sprintf2("%s/%s", path, el); |
| 258 | rv = checkpath(req, fd, newpath, rest + 1, final); |
| 259 | free(newpath); |
| 260 | return(rv); |
| 261 | } else if(S_ISREG(sb.st_mode)) { |
| 262 | newpath = sprintf2("%s/%s", path, el); |
| 263 | replrest(req, rest); |
| 264 | handlefile(req, fd, newpath); |
| 265 | free(newpath); |
| 266 | return(1); |
| 267 | } |
| 268 | handle404(req, fd, sprintf3("%s/", path)); |
| 269 | return(1); |
| 270 | } |
| 271 | if(!strchr(el, '.') && ((newpath = findfile(path, el, NULL)) != NULL)) { |
| 272 | replrest(req, rest); |
| 273 | handlefile(req, fd, newpath); |
| 274 | free(newpath); |
| 275 | return(1); |
| 276 | } |
| 277 | return(0); |
| 278 | } |
| 279 | |
| 280 | static int checkdir(struct hthead *req, int fd, char *path, char *rest) |
| 281 | { |
| 282 | char *cpath, *newpath; |
| 283 | struct config *cf, *ccf; |
| 284 | struct child *ch; |
| 285 | struct stat sb; |
| 286 | int rv; |
| 287 | |
| 288 | cf = getconfig(path); |
| 289 | if((cf->capture != NULL) && (cf->caproot || !cf->path || strcmp(cf->path, "."))) { |
| 290 | cpath = sprintf2("%s/", path); |
| 291 | if((ch = findchild(cpath, cf->capture, &ccf)) == NULL) { |
| 292 | free(cpath); |
| 293 | flog(LOG_ERR, "child %s requested for capture, but was not declared", cf->capture); |
| 294 | simpleerror(fd, 500, "Configuration Error", "The server is erroneously configured. Handler %s was requested, but not declared.", cf->capture); |
| 295 | return(1); |
| 296 | } |
| 297 | free(cpath); |
| 298 | if(*rest == '/') |
| 299 | rest++; |
| 300 | replrest(req, rest); |
| 301 | if(childhandle(ch, req, fd, chinit, ccf?ccf->path:NULL)) |
| 302 | childerror(req, fd); |
| 303 | return(1); |
| 304 | } |
| 305 | if(cf->reparse != NULL) { |
| 306 | newpath = (cf->reparse[0] == '/')?sstrdup(cf->reparse):sprintf2("%s/%s", path, cf->reparse); |
| 307 | rv = stat(newpath, &sb); |
| 308 | if(!rv && S_ISDIR(sb.st_mode)) { |
| 309 | rv = checkpath(req, fd, newpath, rest, !cf->parsecomb); |
| 310 | } else if(!rv && S_ISREG(sb.st_mode)) { |
| 311 | replrest(req, rest); |
| 312 | handlefile(req, fd, newpath); |
| 313 | rv = 1; |
| 314 | } else { |
| 315 | rv = !cf->parsecomb; |
| 316 | } |
| 317 | free(newpath); |
| 318 | if(rv) |
| 319 | return(rv); |
| 320 | } |
| 321 | return(0); |
| 322 | } |
| 323 | |
| 324 | static int checkpath(struct hthead *req, int fd, char *path, char *rest, int final) |
| 325 | { |
| 326 | char *p, *el; |
| 327 | int rv; |
| 328 | |
| 329 | el = NULL; |
| 330 | rv = 0; |
| 331 | |
| 332 | if(!strncmp(path, "./", 2)) |
| 333 | path += 2; |
| 334 | if(checkdir(req, fd, path, rest)) |
| 335 | return(1); |
| 336 | |
| 337 | if((p = strchr(rest, '/')) == NULL) { |
| 338 | el = unquoteurl(rest); |
| 339 | rest = ""; |
| 340 | } else { |
| 341 | char buf[p - rest + 1]; |
| 342 | memcpy(buf, rest, p - rest); |
| 343 | buf[p - rest] = 0; |
| 344 | el = unquoteurl(buf); |
| 345 | rest = p; |
| 346 | } |
| 347 | if(el == NULL) { |
| 348 | simpleerror(fd, 400, "Bad Request", "The requested URL contains an invalid escape sequence."); |
| 349 | rv = 1; |
| 350 | goto out; |
| 351 | } |
| 352 | if(strchr(el, '/') || (!*el && *rest)) { |
| 353 | rv = 0; |
| 354 | goto out; |
| 355 | } |
| 356 | if(!*el) { |
| 357 | replrest(req, rest); |
| 358 | handledir(req, fd, path); |
| 359 | rv = 1; |
| 360 | goto out; |
| 361 | } |
| 362 | rv = checkentry(req, fd, path, rest, el, final); |
| 363 | |
| 364 | out: |
| 365 | if(final && !rv) { |
| 366 | handle404(req, fd, sprintf3("%s/", path)); |
| 367 | rv = 1; |
| 368 | } |
| 369 | if(el != NULL) |
| 370 | free(el); |
| 371 | return(rv); |
| 372 | } |
| 373 | |
| 374 | static void serve(struct hthead *req, int fd) |
| 375 | { |
| 376 | now = time(NULL); |
| 377 | checkpath(req, fd, ".", req->rest, 1); |
| 378 | } |
| 379 | |
| 380 | static void chldhandler(int sig) |
| 381 | { |
| 382 | pid_t pid; |
| 383 | int st; |
| 384 | |
| 385 | while((pid = waitpid(-1, &st, WNOHANG)) > 0) { |
| 386 | if(WCOREDUMP(st)) |
| 387 | flog(LOG_WARNING, "child process %i dumped core", pid); |
| 388 | } |
| 389 | } |
| 390 | |
| 391 | static void sighandler(int sig) |
| 392 | { |
| 393 | } |
| 394 | |
| 395 | static void usage(FILE *out) |
| 396 | { |
| 397 | fprintf(out, "usage: dirplex [-hN] [-c CONFIG] DIR\n"); |
| 398 | } |
| 399 | |
| 400 | int main(int argc, char **argv) |
| 401 | { |
| 402 | int c; |
| 403 | int nodef; |
| 404 | char *gcf, *lcf, *clcf; |
| 405 | struct hthead *req; |
| 406 | int fd; |
| 407 | |
| 408 | nodef = 0; |
| 409 | lcf = NULL; |
| 410 | while((c = getopt(argc, argv, "hNc:")) >= 0) { |
| 411 | switch(c) { |
| 412 | case 'h': |
| 413 | usage(stdout); |
| 414 | exit(0); |
| 415 | case 'N': |
| 416 | nodef = 1; |
| 417 | break; |
| 418 | case 'c': |
| 419 | lcf = optarg; |
| 420 | break; |
| 421 | default: |
| 422 | usage(stderr); |
| 423 | exit(1); |
| 424 | } |
| 425 | } |
| 426 | if(argc - optind < 1) { |
| 427 | usage(stderr); |
| 428 | exit(1); |
| 429 | } |
| 430 | if(!nodef) { |
| 431 | if((gcf = findstdconf("ashd/dirplex.rc")) != NULL) { |
| 432 | gconfig = readconfig(gcf); |
| 433 | free(gcf); |
| 434 | } |
| 435 | } |
| 436 | if(lcf != NULL) { |
| 437 | if(strchr(lcf, '/') == NULL) { |
| 438 | if((clcf = findstdconf(sprintf3("ashd/%s", lcf))) == NULL) { |
| 439 | flog(LOG_ERR, "could not find requested configuration `%s'", lcf); |
| 440 | exit(1); |
| 441 | } |
| 442 | if((lconfig = readconfig(clcf)) == NULL) |
| 443 | exit(1); |
| 444 | free(clcf); |
| 445 | } else { |
| 446 | if((lconfig = readconfig(lcf)) == NULL) |
| 447 | exit(1); |
| 448 | } |
| 449 | } |
| 450 | if(chdir(argv[optind])) { |
| 451 | flog(LOG_ERR, "could not change directory to %s: %s", argv[optind], strerror(errno)); |
| 452 | exit(1); |
| 453 | } |
| 454 | signal(SIGCHLD, chldhandler); |
| 455 | signal(SIGPIPE, sighandler); |
| 456 | while(1) { |
| 457 | if((fd = recvreq(0, &req)) < 0) { |
| 458 | if(errno != 0) |
| 459 | flog(LOG_ERR, "recvreq: %s", strerror(errno)); |
| 460 | break; |
| 461 | } |
| 462 | serve(req, fd); |
| 463 | freehthead(req); |
| 464 | close(fd); |
| 465 | } |
| 466 | return(0); |
| 467 | } |