1 /* 2 * Copyright (c) 1993 Paul Kranenburg 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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by Paul Kranenburg. 16 * 4. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef lint 32 static const char rcsid[] = 33 "$FreeBSD$"; 34 #endif /* not lint */ 35 36 #include <sys/wait.h> 37 #include <machine/elf.h> 38 #include <a.out.h> 39 #include <dlfcn.h> 40 #include <err.h> 41 #include <fcntl.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <unistd.h> 45 46 extern void dump_file(const char *); 47 extern int error_count; 48 49 void 50 usage() 51 { 52 fprintf(stderr, "usage: ldd [-a] [-v] [-f format] program ...\n"); 53 exit(1); 54 } 55 56 int 57 main(argc, argv) 58 int argc; 59 char *argv[]; 60 { 61 char *fmt1 = NULL, *fmt2 = NULL; 62 int rval; 63 int c; 64 int aflag, vflag; 65 66 aflag = vflag = 0; 67 68 while ((c = getopt(argc, argv, "avf:")) != -1) { 69 switch (c) { 70 case 'a': 71 aflag++; 72 break; 73 case 'v': 74 vflag++; 75 break; 76 case 'f': 77 if (fmt1) { 78 if (fmt2) 79 errx(1, "too many formats"); 80 fmt2 = optarg; 81 } else 82 fmt1 = optarg; 83 break; 84 default: 85 usage(); 86 /*NOTREACHED*/ 87 } 88 } 89 argc -= optind; 90 argv += optind; 91 92 if (vflag && fmt1) 93 errx(1, "-v may not be used with -f"); 94 95 if (argc <= 0) { 96 usage(); 97 /*NOTREACHED*/ 98 } 99 100 #ifdef __i386__ 101 if (vflag) { 102 for (c = 0; c < argc; c++) 103 dump_file(argv[c]); 104 exit(error_count == 0 ? EXIT_SUCCESS : EXIT_FAILURE); 105 } 106 #endif 107 108 /* ld.so magic */ 109 setenv("LD_TRACE_LOADED_OBJECTS", "yes", 1); 110 if (fmt1) 111 setenv("LD_TRACE_LOADED_OBJECTS_FMT1", fmt1, 1); 112 if (fmt2) 113 setenv("LD_TRACE_LOADED_OBJECTS_FMT2", fmt2, 1); 114 115 rval = 0; 116 for ( ; argc > 0; argc--, argv++) { 117 int fd; 118 union { 119 struct exec aout; 120 Elf_Ehdr elf; 121 } hdr; 122 int n; 123 int status; 124 int file_ok; 125 int is_shlib; 126 127 if ((fd = open(*argv, O_RDONLY, 0)) < 0) { 128 warn("%s", *argv); 129 rval |= 1; 130 continue; 131 } 132 if ((n = read(fd, &hdr, sizeof hdr)) == -1) { 133 warn("%s: can't read program header", *argv); 134 (void)close(fd); 135 rval |= 1; 136 continue; 137 } 138 139 file_ok = 1; 140 is_shlib = 0; 141 if (n >= sizeof hdr.aout && !N_BADMAG(hdr.aout)) { 142 /* a.out file */ 143 if ((N_GETFLAG(hdr.aout) & EX_DPMASK) != EX_DYNAMIC 144 #if 1 /* Compatibility */ 145 || hdr.aout.a_entry < __LDPGSZ 146 #endif 147 ) { 148 warnx("%s: not a dynamic executable", *argv); 149 file_ok = 0; 150 } 151 } else if (n >= sizeof hdr.elf && IS_ELF(hdr.elf)) { 152 Elf_Ehdr ehdr; 153 Elf_Phdr phdr; 154 int dynamic = 0, i; 155 156 if (lseek(fd, 0, SEEK_SET) == -1 || 157 read(fd, &ehdr, sizeof ehdr) != sizeof ehdr || 158 lseek(fd, ehdr.e_phoff, SEEK_SET) == -1 159 ) { 160 warnx("%s: can't read program header", *argv); 161 file_ok = 0; 162 } else { 163 for (i = 0; i < ehdr.e_phnum; i++) { 164 if (read(fd, &phdr, ehdr.e_phentsize) 165 != sizeof phdr) { 166 warnx("%s: can't read program header", 167 *argv); 168 file_ok = 0; 169 break; 170 } 171 if (phdr.p_type == PT_DYNAMIC) 172 dynamic = 1; 173 } 174 } 175 if (!dynamic) { 176 warnx("%s: not a dynamic executable", *argv); 177 file_ok = 0; 178 } else if (hdr.elf.e_type == ET_DYN) { 179 if (hdr.elf.e_ident[EI_OSABI] & ELFOSABI_FREEBSD) { 180 is_shlib = 1; 181 } else { 182 warnx("%s: not a FreeBSD ELF shared " 183 "object", *argv); 184 file_ok = 0; 185 } 186 } 187 } else { 188 warnx("%s: not a dynamic executable", *argv); 189 file_ok = 0; 190 } 191 (void)close(fd); 192 if (!file_ok) { 193 rval |= 1; 194 continue; 195 } 196 197 setenv("LD_TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1); 198 if (aflag) setenv("LD_TRACE_LOADED_OBJECTS_ALL", "1", 1); 199 else if (fmt1 == NULL && fmt2 == NULL) 200 /* Default formats */ 201 printf("%s:\n", *argv); 202 203 fflush(stdout); 204 205 switch (fork()) { 206 case -1: 207 err(1, "fork"); 208 break; 209 default: 210 if (wait(&status) <= 0) { 211 warn("wait"); 212 rval |= 1; 213 } else if (WIFSIGNALED(status)) { 214 fprintf(stderr, "%s: signal %d\n", 215 *argv, WTERMSIG(status)); 216 rval |= 1; 217 } else if (WIFEXITED(status) && WEXITSTATUS(status)) { 218 fprintf(stderr, "%s: exit status %d\n", 219 *argv, WEXITSTATUS(status)); 220 rval |= 1; 221 } 222 break; 223 case 0: 224 if (is_shlib == 0) { 225 execl(*argv, *argv, (char *)NULL); 226 warn("%s", *argv); 227 } else { 228 dlopen(*argv, RTLD_TRACE); 229 warnx("%s: %s", *argv, dlerror()); 230 } 231 _exit(1); 232 } 233 } 234 235 return rval; 236 } 237