1 /* 2 * $FreeBSD$ 3 */ 4 5 #include <sys/types.h> 6 #include <sys/param.h> 7 #include <sys/fcntl.h> 8 #include <sys/mman.h> 9 #include <sys/queue.h> 10 #include <sys/stat.h> 11 #include <dirent.h> 12 #include <errno.h> 13 #include <stdlib.h> 14 #include <string.h> 15 16 #include "debug.h" 17 #include "rtld.h" 18 #include "libmap.h" 19 #include "paths.h" 20 21 TAILQ_HEAD(lm_list, lm); 22 struct lm { 23 char *f; 24 char *t; 25 TAILQ_ENTRY(lm) lm_link; 26 }; 27 28 static TAILQ_HEAD(lmp_list, lmp) lmp_head = TAILQ_HEAD_INITIALIZER(lmp_head); 29 struct lmp { 30 char *p; 31 enum { T_EXACT=0, T_BASENAME, T_DIRECTORY } type; 32 struct lm_list lml; 33 TAILQ_ENTRY(lmp) lmp_link; 34 }; 35 36 static TAILQ_HEAD(lmc_list, lmc) lmc_head = TAILQ_HEAD_INITIALIZER(lmc_head); 37 struct lmc { 38 char *path; 39 dev_t dev; 40 ino_t ino; 41 TAILQ_ENTRY(lmc) next; 42 }; 43 44 static int lm_count; 45 46 static void lmc_parse(char *, size_t); 47 static void lmc_parse_file(const char *); 48 static void lmc_parse_dir(const char *); 49 static void lm_add(const char *, const char *, const char *); 50 static void lm_free(struct lm_list *); 51 static char *lml_find(struct lm_list *, const char *); 52 static struct lm_list *lmp_find(const char *); 53 static struct lm_list *lmp_init(char *); 54 static const char *quickbasename(const char *); 55 56 #define iseol(c) (((c) == '#') || ((c) == '\0') || \ 57 ((c) == '\n') || ((c) == '\r')) 58 59 /* 60 * Do not use ctype.h macros, which rely on working TLS. It is 61 * too early to have thread-local variables functional. 62 */ 63 #define rtld_isspace(c) ((c) == ' ' || (c) == '\t') 64 65 int 66 lm_init(char *libmap_override) 67 { 68 char *p; 69 70 dbg("lm_init(\"%s\")", libmap_override); 71 TAILQ_INIT(&lmp_head); 72 73 lmc_parse_file(ld_path_libmap_conf); 74 75 if (libmap_override) { 76 /* 77 * Do some character replacement to make $LDLIBMAP look 78 * like a text file, then parse it. 79 */ 80 libmap_override = xstrdup(libmap_override); 81 for (p = libmap_override; *p; p++) { 82 switch (*p) { 83 case '=': 84 *p = ' '; 85 break; 86 case ',': 87 *p = '\n'; 88 break; 89 } 90 } 91 lmc_parse(libmap_override, p - libmap_override); 92 free(libmap_override); 93 } 94 95 return (lm_count == 0); 96 } 97 98 static void 99 lmc_parse_file(const char *path) 100 { 101 struct lmc *p; 102 char *lm_map; 103 struct stat st; 104 ssize_t retval; 105 int fd; 106 107 TAILQ_FOREACH(p, &lmc_head, next) { 108 if (strcmp(p->path, path) == 0) 109 return; 110 } 111 112 fd = open(path, O_RDONLY | O_CLOEXEC); 113 if (fd == -1) { 114 dbg("lm_parse_file: open(\"%s\") failed, %s", path, 115 rtld_strerror(errno)); 116 return; 117 } 118 if (fstat(fd, &st) == -1) { 119 close(fd); 120 dbg("lm_parse_file: fstat(\"%s\") failed, %s", path, 121 rtld_strerror(errno)); 122 return; 123 } 124 125 TAILQ_FOREACH(p, &lmc_head, next) { 126 if (p->dev == st.st_dev && p->ino == st.st_ino) { 127 close(fd); 128 return; 129 } 130 } 131 132 lm_map = xmalloc(st.st_size); 133 retval = read(fd, lm_map, st.st_size); 134 if (retval != st.st_size) { 135 close(fd); 136 free(lm_map); 137 dbg("lm_parse_file: read(\"%s\") failed, %s", path, 138 rtld_strerror(errno)); 139 return; 140 } 141 close(fd); 142 p = xmalloc(sizeof(struct lmc)); 143 p->path = xstrdup(path); 144 p->dev = st.st_dev; 145 p->ino = st.st_ino; 146 TAILQ_INSERT_HEAD(&lmc_head, p, next); 147 lmc_parse(lm_map, st.st_size); 148 free(lm_map); 149 } 150 151 static void 152 lmc_parse_dir(const char *idir) 153 { 154 DIR *d; 155 struct dirent *dp; 156 struct lmc *p; 157 char conffile[MAXPATHLEN]; 158 char *ext; 159 160 TAILQ_FOREACH(p, &lmc_head, next) { 161 if (strcmp(p->path, idir) == 0) 162 return; 163 } 164 d = opendir(idir); 165 if (d == NULL) 166 return; 167 168 p = xmalloc(sizeof(struct lmc)); 169 p->path = xstrdup(idir); 170 p->dev = NODEV; 171 p->ino = 0; 172 TAILQ_INSERT_HEAD(&lmc_head, p, next); 173 174 while ((dp = readdir(d)) != NULL) { 175 if (dp->d_ino == 0) 176 continue; 177 if (dp->d_type != DT_REG) 178 continue; 179 ext = strrchr(dp->d_name, '.'); 180 if (ext == NULL) 181 continue; 182 if (strcmp(ext, ".conf") != 0) 183 continue; 184 if (strlcpy(conffile, idir, MAXPATHLEN) >= MAXPATHLEN) 185 continue; /* too long */ 186 if (strlcat(conffile, "/", MAXPATHLEN) >= MAXPATHLEN) 187 continue; /* too long */ 188 if (strlcat(conffile, dp->d_name, MAXPATHLEN) >= MAXPATHLEN) 189 continue; /* too long */ 190 lmc_parse_file(conffile); 191 } 192 closedir(d); 193 } 194 195 static void 196 lmc_parse(char *lm_p, size_t lm_len) 197 { 198 char *cp, *f, *t, *c, *p; 199 char prog[MAXPATHLEN]; 200 /* allow includedir + full length path */ 201 char line[MAXPATHLEN + 13]; 202 size_t cnt, i; 203 204 cnt = 0; 205 p = NULL; 206 while (cnt < lm_len) { 207 i = 0; 208 while (cnt < lm_len && lm_p[cnt] != '\n' && 209 i < sizeof(line) - 1) { 210 line[i] = lm_p[cnt]; 211 cnt++; 212 i++; 213 } 214 line[i] = '\0'; 215 while (cnt < lm_len && lm_p[cnt] != '\n') 216 cnt++; 217 /* skip over nl */ 218 cnt++; 219 220 cp = &line[0]; 221 t = f = c = NULL; 222 223 /* Skip over leading space */ 224 while (rtld_isspace(*cp)) 225 cp++; 226 227 /* Found a comment or EOL */ 228 if (iseol(*cp)) 229 continue; 230 231 /* Found a constraint selector */ 232 if (*cp == '[') { 233 cp++; 234 235 /* Skip leading space */ 236 while (rtld_isspace(*cp)) 237 cp++; 238 239 /* Found comment, EOL or end of selector */ 240 if (iseol(*cp) || *cp == ']') 241 continue; 242 243 c = cp++; 244 /* Skip to end of word */ 245 while (!rtld_isspace(*cp) && !iseol(*cp) && *cp != ']') 246 cp++; 247 248 /* Skip and zero out trailing space */ 249 while (rtld_isspace(*cp)) 250 *cp++ = '\0'; 251 252 /* Check if there is a closing brace */ 253 if (*cp != ']') 254 continue; 255 256 /* Terminate string if there was no trailing space */ 257 *cp++ = '\0'; 258 259 /* 260 * There should be nothing except whitespace or comment 261 from this point to the end of the line. 262 */ 263 while (rtld_isspace(*cp)) 264 cp++; 265 if (!iseol(*cp)) 266 continue; 267 268 if (strlcpy(prog, c, sizeof prog) >= sizeof prog) 269 continue; 270 p = prog; 271 continue; 272 } 273 274 /* Parse the 'from' candidate. */ 275 f = cp++; 276 while (!rtld_isspace(*cp) && !iseol(*cp)) 277 cp++; 278 279 /* Skip and zero out the trailing whitespace */ 280 while (rtld_isspace(*cp)) 281 *cp++ = '\0'; 282 283 /* Found a comment or EOL */ 284 if (iseol(*cp)) 285 continue; 286 287 /* Parse 'to' mapping */ 288 t = cp++; 289 while (!rtld_isspace(*cp) && !iseol(*cp)) 290 cp++; 291 292 /* Skip and zero out the trailing whitespace */ 293 while (rtld_isspace(*cp)) 294 *cp++ = '\0'; 295 296 /* Should be no extra tokens at this point */ 297 if (!iseol(*cp)) 298 continue; 299 300 *cp = '\0'; 301 if (strcmp(f, "includedir") == 0) 302 lmc_parse_dir(t); 303 else if (strcmp(f, "include") == 0) 304 lmc_parse_file(t); 305 else 306 lm_add(p, f, t); 307 } 308 } 309 310 static void 311 lm_free(struct lm_list *lml) 312 { 313 struct lm *lm; 314 315 dbg("%s(%p)", __func__, lml); 316 317 while (!TAILQ_EMPTY(lml)) { 318 lm = TAILQ_FIRST(lml); 319 TAILQ_REMOVE(lml, lm, lm_link); 320 free(lm->f); 321 free(lm->t); 322 free(lm); 323 } 324 } 325 326 void 327 lm_fini(void) 328 { 329 struct lmp *lmp; 330 struct lmc *p; 331 332 dbg("%s()", __func__); 333 334 while (!TAILQ_EMPTY(&lmc_head)) { 335 p = TAILQ_FIRST(&lmc_head); 336 TAILQ_REMOVE(&lmc_head, p, next); 337 free(p->path); 338 free(p); 339 } 340 341 while (!TAILQ_EMPTY(&lmp_head)) { 342 lmp = TAILQ_FIRST(&lmp_head); 343 TAILQ_REMOVE(&lmp_head, lmp, lmp_link); 344 free(lmp->p); 345 lm_free(&lmp->lml); 346 free(lmp); 347 } 348 } 349 350 static void 351 lm_add(const char *p, const char *f, const char *t) 352 { 353 struct lm_list *lml; 354 struct lm *lm; 355 const char *t1; 356 357 if (p == NULL) 358 p = "$DEFAULT$"; 359 360 dbg("%s(\"%s\", \"%s\", \"%s\")", __func__, p, f, t); 361 362 if ((lml = lmp_find(p)) == NULL) 363 lml = lmp_init(xstrdup(p)); 364 365 t1 = lml_find(lml, f); 366 if (t1 == NULL || strcmp(t1, t) != 0) { 367 lm = xmalloc(sizeof(struct lm)); 368 lm->f = xstrdup(f); 369 lm->t = xstrdup(t); 370 TAILQ_INSERT_HEAD(lml, lm, lm_link); 371 lm_count++; 372 } 373 } 374 375 char * 376 lm_find(const char *p, const char *f) 377 { 378 struct lm_list *lml; 379 char *t; 380 381 dbg("%s(\"%s\", \"%s\")", __func__, p, f); 382 383 if (p != NULL && (lml = lmp_find(p)) != NULL) { 384 t = lml_find(lml, f); 385 if (t != NULL) { 386 /* 387 * Add a global mapping if we have 388 * a successful constrained match. 389 */ 390 lm_add(NULL, f, t); 391 return (t); 392 } 393 } 394 lml = lmp_find("$DEFAULT$"); 395 if (lml != NULL) 396 return (lml_find(lml, f)); 397 return (NULL); 398 } 399 400 /* 401 * Given a libmap translation list and a library name, return the 402 * replacement library, or NULL. 403 */ 404 char * 405 lm_findn(const char *p, const char *f, const size_t n) 406 { 407 char pathbuf[64], *s, *t; 408 409 if (n < sizeof(pathbuf) - 1) 410 s = pathbuf; 411 else 412 s = xmalloc(n + 1); 413 memcpy(s, f, n); 414 s[n] = '\0'; 415 t = lm_find(p, s); 416 if (s != pathbuf) 417 free(s); 418 return (t); 419 } 420 421 static char * 422 lml_find(struct lm_list *lmh, const char *f) 423 { 424 struct lm *lm; 425 426 dbg("%s(%p, \"%s\")", __func__, lmh, f); 427 428 TAILQ_FOREACH(lm, lmh, lm_link) { 429 if (strcmp(f, lm->f) == 0) 430 return (lm->t); 431 } 432 return (NULL); 433 } 434 435 /* 436 * Given an executable name, return a pointer to the translation list or 437 * NULL if no matches. 438 */ 439 static struct lm_list * 440 lmp_find(const char *n) 441 { 442 struct lmp *lmp; 443 444 dbg("%s(\"%s\")", __func__, n); 445 446 TAILQ_FOREACH(lmp, &lmp_head, lmp_link) { 447 if ((lmp->type == T_EXACT && strcmp(n, lmp->p) == 0) || 448 (lmp->type == T_DIRECTORY && strncmp(n, lmp->p, 449 strlen(lmp->p)) == 0) || 450 (lmp->type == T_BASENAME && strcmp(quickbasename(n), 451 lmp->p) == 0)) 452 return (&lmp->lml); 453 } 454 return (NULL); 455 } 456 457 static struct lm_list * 458 lmp_init(char *n) 459 { 460 struct lmp *lmp; 461 462 dbg("%s(\"%s\")", __func__, n); 463 464 lmp = xmalloc(sizeof(struct lmp)); 465 lmp->p = n; 466 if (n[strlen(n) - 1] == '/') 467 lmp->type = T_DIRECTORY; 468 else if (strchr(n,'/') == NULL) 469 lmp->type = T_BASENAME; 470 else 471 lmp->type = T_EXACT; 472 TAILQ_INIT(&lmp->lml); 473 TAILQ_INSERT_HEAD(&lmp_head, lmp, lmp_link); 474 475 return (&lmp->lml); 476 } 477 478 /* 479 * libc basename is overkill. Return a pointer to the character after 480 * the last /, or the original string if there are no slashes. 481 */ 482 static const char * 483 quickbasename(const char *path) 484 { 485 const char *p; 486 487 for (p = path; *path != '\0'; path++) { 488 if (*path == '/') 489 p = path + 1; 490 } 491 return (p); 492 } 493