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 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(char *); 48 static void lmc_parse_dir(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(char *path) 100 { 101 struct lmc *p; 102 struct stat st; 103 ssize_t retval; 104 int fd; 105 char *lm_map; 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(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; 203 int i; 204 205 cnt = 0; 206 p = NULL; 207 while (cnt < lm_len) { 208 i = 0; 209 while (cnt < lm_len && lm_p[cnt] != '\n' && 210 i < sizeof(line) - 1) { 211 line[i] = lm_p[cnt]; 212 cnt++; 213 i++; 214 } 215 line[i] = '\0'; 216 while (cnt < lm_len && lm_p[cnt] != '\n') 217 cnt++; 218 /* skip over nl */ 219 cnt++; 220 221 cp = &line[0]; 222 t = f = c = NULL; 223 224 /* Skip over leading space */ 225 while (rtld_isspace(*cp)) cp++; 226 227 /* Found a comment or EOL */ 228 if (iseol(*cp)) continue; 229 230 /* Found a constraint selector */ 231 if (*cp == '[') { 232 cp++; 233 234 /* Skip leading space */ 235 while (rtld_isspace(*cp)) cp++; 236 237 /* Found comment, EOL or end of selector */ 238 if (iseol(*cp) || *cp == ']') 239 continue; 240 241 c = cp++; 242 /* Skip to end of word */ 243 while (!rtld_isspace(*cp) && !iseol(*cp) && *cp != ']') 244 cp++; 245 246 /* Skip and zero out trailing space */ 247 while (rtld_isspace(*cp)) *cp++ = '\0'; 248 249 /* Check if there is a closing brace */ 250 if (*cp != ']') continue; 251 252 /* Terminate string if there was no trailing space */ 253 *cp++ = '\0'; 254 255 /* 256 * There should be nothing except whitespace or comment 257 from this point to the end of the line. 258 */ 259 while(rtld_isspace(*cp)) cp++; 260 if (!iseol(*cp)) continue; 261 262 if (strlcpy(prog, c, sizeof prog) >= sizeof prog) 263 continue; 264 p = prog; 265 continue; 266 } 267 268 /* Parse the 'from' candidate. */ 269 f = cp++; 270 while (!rtld_isspace(*cp) && !iseol(*cp)) cp++; 271 272 /* Skip and zero out the trailing whitespace */ 273 while (rtld_isspace(*cp)) *cp++ = '\0'; 274 275 /* Found a comment or EOL */ 276 if (iseol(*cp)) continue; 277 278 /* Parse 'to' mapping */ 279 t = cp++; 280 while (!rtld_isspace(*cp) && !iseol(*cp)) cp++; 281 282 /* Skip and zero out the trailing whitespace */ 283 while (rtld_isspace(*cp)) *cp++ = '\0'; 284 285 /* Should be no extra tokens at this point */ 286 if (!iseol(*cp)) continue; 287 288 *cp = '\0'; 289 if (strcmp(f, "includedir") == 0) 290 lmc_parse_dir(t); 291 else if (strcmp(f, "include") == 0) 292 lmc_parse_file(t); 293 else 294 lm_add(p, f, t); 295 } 296 } 297 298 static void 299 lm_free (struct lm_list *lml) 300 { 301 struct lm *lm; 302 303 dbg("%s(%p)", __func__, lml); 304 305 while (!TAILQ_EMPTY(lml)) { 306 lm = TAILQ_FIRST(lml); 307 TAILQ_REMOVE(lml, lm, lm_link); 308 free(lm->f); 309 free(lm->t); 310 free(lm); 311 } 312 return; 313 } 314 315 void 316 lm_fini (void) 317 { 318 struct lmp *lmp; 319 struct lmc *p; 320 321 dbg("%s()", __func__); 322 323 while (!TAILQ_EMPTY(&lmc_head)) { 324 p = TAILQ_FIRST(&lmc_head); 325 TAILQ_REMOVE(&lmc_head, p, next); 326 free(p->path); 327 free(p); 328 } 329 330 while (!TAILQ_EMPTY(&lmp_head)) { 331 lmp = TAILQ_FIRST(&lmp_head); 332 TAILQ_REMOVE(&lmp_head, lmp, lmp_link); 333 free(lmp->p); 334 lm_free(&lmp->lml); 335 free(lmp); 336 } 337 return; 338 } 339 340 static void 341 lm_add (const char *p, const char *f, const char *t) 342 { 343 struct lm_list *lml; 344 struct lm *lm; 345 346 if (p == NULL) 347 p = "$DEFAULT$"; 348 349 dbg("%s(\"%s\", \"%s\", \"%s\")", __func__, p, f, t); 350 351 if ((lml = lmp_find(p)) == NULL) 352 lml = lmp_init(xstrdup(p)); 353 354 lm = xmalloc(sizeof(struct lm)); 355 lm->f = xstrdup(f); 356 lm->t = xstrdup(t); 357 TAILQ_INSERT_HEAD(lml, lm, lm_link); 358 lm_count++; 359 } 360 361 char * 362 lm_find (const char *p, const char *f) 363 { 364 struct lm_list *lml; 365 char *t; 366 367 dbg("%s(\"%s\", \"%s\")", __func__, p, f); 368 369 if (p != NULL && (lml = lmp_find(p)) != NULL) { 370 t = lml_find(lml, f); 371 if (t != NULL) { 372 /* 373 * Add a global mapping if we have 374 * a successful constrained match. 375 */ 376 lm_add(NULL, f, t); 377 return (t); 378 } 379 } 380 lml = lmp_find("$DEFAULT$"); 381 if (lml != NULL) 382 return (lml_find(lml, f)); 383 else 384 return (NULL); 385 } 386 387 /* Given a libmap translation list and a library name, return the 388 replacement library, or NULL */ 389 char * 390 lm_findn (const char *p, const char *f, const int n) 391 { 392 char pathbuf[64], *s, *t; 393 394 if (n < sizeof(pathbuf) - 1) 395 s = pathbuf; 396 else 397 s = xmalloc(n + 1); 398 memcpy(s, f, n); 399 s[n] = '\0'; 400 t = lm_find(p, s); 401 if (s != pathbuf) 402 free(s); 403 return (t); 404 } 405 406 static char * 407 lml_find (struct lm_list *lmh, const char *f) 408 { 409 struct lm *lm; 410 411 dbg("%s(%p, \"%s\")", __func__, lmh, f); 412 413 TAILQ_FOREACH(lm, lmh, lm_link) 414 if (strcmp(f, lm->f) == 0) 415 return (lm->t); 416 return (NULL); 417 } 418 419 /* Given an executable name, return a pointer to the translation list or 420 NULL if no matches */ 421 static struct lm_list * 422 lmp_find (const char *n) 423 { 424 struct lmp *lmp; 425 426 dbg("%s(\"%s\")", __func__, n); 427 428 TAILQ_FOREACH(lmp, &lmp_head, lmp_link) 429 if ((lmp->type == T_EXACT && strcmp(n, lmp->p) == 0) || 430 (lmp->type == T_DIRECTORY && strncmp(n, lmp->p, strlen(lmp->p)) == 0) || 431 (lmp->type == T_BASENAME && strcmp(quickbasename(n), lmp->p) == 0)) 432 return (&lmp->lml); 433 return (NULL); 434 } 435 436 static struct lm_list * 437 lmp_init (char *n) 438 { 439 struct lmp *lmp; 440 441 dbg("%s(\"%s\")", __func__, n); 442 443 lmp = xmalloc(sizeof(struct lmp)); 444 lmp->p = n; 445 if (n[strlen(n)-1] == '/') 446 lmp->type = T_DIRECTORY; 447 else if (strchr(n,'/') == NULL) 448 lmp->type = T_BASENAME; 449 else 450 lmp->type = T_EXACT; 451 TAILQ_INIT(&lmp->lml); 452 TAILQ_INSERT_HEAD(&lmp_head, lmp, lmp_link); 453 454 return (&lmp->lml); 455 } 456 457 /* libc basename is overkill. Return a pointer to the character after the 458 last /, or the original string if there are no slashes. */ 459 static const char * 460 quickbasename (const char *path) 461 { 462 const char *p = path; 463 for (; *path; path++) { 464 if (*path == '/') 465 p = path+1; 466 } 467 return (p); 468 } 469