1 /*- 2 * Copyright (c) 1998 John D. Polstra 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/mman.h> 31 #include <sys/stat.h> 32 33 #include <ctype.h> 34 #include <dirent.h> 35 #include <elf.h> 36 #include <err.h> 37 #include <errno.h> 38 #include <fcntl.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include <unistd.h> 43 44 #include "ldconfig.h" 45 46 #define MAXDIRS 1024 /* Maximum directories in path */ 47 #define MAXFILESIZE (16*1024) /* Maximum hints file size */ 48 49 static void add_dir(const char *, const char *); 50 static void read_dirs_from_file(const char *, const char *); 51 static void read_elf_hints(const char *, int); 52 static void write_elf_hints(const char *); 53 54 static const char *dirs[MAXDIRS]; 55 static int ndirs; 56 57 static void 58 add_dir(const char *hintsfile, const char *name) 59 { 60 int i; 61 62 for (i = 0; i < ndirs; i++) 63 if (strcmp(dirs[i], name) == 0) 64 return; 65 if (ndirs >= MAXDIRS) 66 errx(1, "\"%s\": Too many directories in path", hintsfile); 67 dirs[ndirs++] = name; 68 } 69 70 void 71 list_elf_hints(const char *hintsfile) 72 { 73 int i; 74 int nlibs; 75 76 read_elf_hints(hintsfile, 1); 77 printf("%s:\n", hintsfile); 78 printf("\tsearch directories:"); 79 for (i = 0; i < ndirs; i++) 80 printf("%c%s", i == 0 ? ' ' : ':', dirs[i]); 81 printf("\n"); 82 83 nlibs = 0; 84 for (i = 0; i < ndirs; i++) { 85 DIR *dirp; 86 struct dirent *dp; 87 88 if ((dirp = opendir(dirs[i])) == NULL) 89 continue; 90 while ((dp = readdir(dirp)) != NULL) { 91 int len; 92 int namelen; 93 const char *name; 94 const char *vers; 95 96 /* Name can't be shorter than "libx.so.0" */ 97 if ((len = strlen(dp->d_name)) < 9 || 98 strncmp(dp->d_name, "lib", 3) != 0) 99 continue; 100 name = dp->d_name + 3; 101 vers = dp->d_name + len; 102 while (vers > dp->d_name && isdigit(*(vers-1))) 103 vers--; 104 if (vers == dp->d_name + len) 105 continue; 106 if (vers < dp->d_name + 4 || 107 strncmp(vers - 4, ".so.", 4) != 0) 108 continue; 109 110 /* We have a valid shared library name. */ 111 namelen = (vers - 4) - name; 112 printf("\t%d:-l%.*s.%s => %s/%s\n", nlibs, 113 namelen, name, vers, dirs[i], dp->d_name); 114 nlibs++; 115 } 116 closedir(dirp); 117 } 118 } 119 120 static void 121 read_dirs_from_file(const char *hintsfile, const char *listfile) 122 { 123 FILE *fp; 124 char buf[MAXPATHLEN]; 125 int linenum; 126 127 if ((fp = fopen(listfile, "r")) == NULL) 128 err(1, "%s", listfile); 129 130 linenum = 0; 131 while (fgets(buf, sizeof buf, fp) != NULL) { 132 char *cp, *sp; 133 134 linenum++; 135 cp = buf; 136 /* Skip leading white space. */ 137 while (isspace(*cp)) 138 cp++; 139 if (*cp == '#' || *cp == '\0') 140 continue; 141 sp = cp; 142 /* Advance over the directory name. */ 143 while (!isspace(*cp) && *cp != '\0') 144 cp++; 145 /* Terminate the string and skip trailing white space. */ 146 if (*cp != '\0') { 147 *cp++ = '\0'; 148 while (isspace(*cp)) 149 cp++; 150 } 151 /* Now we had better be at the end of the line. */ 152 if (*cp != '\0') 153 warnx("%s:%d: trailing characters ignored", 154 listfile, linenum); 155 156 if ((sp = strdup(sp)) == NULL) 157 errx(1, "Out of memory"); 158 add_dir(hintsfile, sp); 159 } 160 161 fclose(fp); 162 } 163 164 static void 165 read_elf_hints(const char *hintsfile, int must_exist) 166 { 167 int fd; 168 struct stat s; 169 void *mapbase; 170 struct elfhints_hdr *hdr; 171 char *strtab; 172 char *dirlist; 173 char *p; 174 175 if ((fd = open(hintsfile, O_RDONLY)) == -1) { 176 if (errno == ENOENT && !must_exist) 177 return; 178 err(1, "Cannot open \"%s\"", hintsfile); 179 } 180 if (fstat(fd, &s) == -1) 181 err(1, "Cannot stat \"%s\"", hintsfile); 182 if (s.st_size > MAXFILESIZE) 183 errx(1, "\"%s\" is unreasonably large", hintsfile); 184 /* 185 * We use a read-write, private mapping so that we can null-terminate 186 * some strings in it without affecting the underlying file. 187 */ 188 mapbase = mmap(NULL, s.st_size, PROT_READ|PROT_WRITE, 189 MAP_PRIVATE, fd, 0); 190 if (mapbase == MAP_FAILED) 191 err(1, "Cannot mmap \"%s\"", hintsfile); 192 close(fd); 193 194 hdr = (struct elfhints_hdr *)mapbase; 195 if (hdr->magic != ELFHINTS_MAGIC) 196 errx(1, "\"%s\": invalid file format", hintsfile); 197 if (hdr->version != 1) 198 errx(1, "\"%s\": unrecognized file version (%d)", hintsfile, 199 hdr->version); 200 201 strtab = (char *)mapbase + hdr->strtab; 202 dirlist = strtab + hdr->dirlist; 203 204 if (*dirlist != '\0') 205 while ((p = strsep(&dirlist, ":")) != NULL) 206 add_dir(hintsfile, p); 207 } 208 209 void 210 update_elf_hints(const char *hintsfile, int argc, char **argv, int merge) 211 { 212 int i; 213 214 if (merge) 215 read_elf_hints(hintsfile, 0); 216 for (i = 0; i < argc; i++) { 217 struct stat s; 218 219 if (stat(argv[i], &s) == -1) 220 warn("warning: %s", argv[i]); 221 else if (S_ISREG(s.st_mode)) 222 read_dirs_from_file(hintsfile, argv[i]); 223 else 224 add_dir(hintsfile, argv[i]); 225 } 226 write_elf_hints(hintsfile); 227 } 228 229 static void 230 write_elf_hints(const char *hintsfile) 231 { 232 struct elfhints_hdr hdr; 233 char *tempname; 234 int fd; 235 FILE *fp; 236 int i; 237 238 if (asprintf(&tempname, "%s.XXXXXX", hintsfile) == -1) 239 errx(1, "Out of memory"); 240 if ((fd = mkstemp(tempname)) == -1) 241 err(1, "mkstemp(%s)", tempname); 242 if (fchmod(fd, 0444) == -1) 243 err(1, "fchmod(%s)", tempname); 244 if ((fp = fdopen(fd, "wb")) == NULL) 245 err(1, "fdopen(%s)", tempname); 246 247 hdr.magic = ELFHINTS_MAGIC; 248 hdr.version = 1; 249 hdr.strtab = sizeof hdr; 250 hdr.strsize = 0; 251 hdr.dirlist = 0; 252 memset(hdr.spare, 0, sizeof hdr.spare); 253 254 /* Count up the size of the string table. */ 255 if (ndirs > 0) { 256 hdr.strsize += strlen(dirs[0]); 257 for (i = 1; i < ndirs; i++) 258 hdr.strsize += 1 + strlen(dirs[i]); 259 } 260 hdr.dirlistlen = hdr.strsize; 261 hdr.strsize++; /* For the null terminator */ 262 263 /* Write the header. */ 264 if (fwrite(&hdr, 1, sizeof hdr, fp) != sizeof hdr) 265 err(1, "%s: write error", tempname); 266 /* Write the strings. */ 267 if (ndirs > 0) { 268 if (fputs(dirs[0], fp) == EOF) 269 err(1, "%s: write error", tempname); 270 for (i = 1; i < ndirs; i++) 271 if (fprintf(fp, ":%s", dirs[i]) < 0) 272 err(1, "%s: write error", tempname); 273 } 274 if (putc('\0', fp) == EOF || fclose(fp) == EOF) 275 err(1, "%s: write error", tempname); 276 277 if (rename(tempname, hintsfile) == -1) 278 err(1, "rename %s to %s", tempname, hintsfile); 279 free(tempname); 280 } 281