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 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include <sys/wait.h> 35 36 #include <machine/elf.h> 37 38 #include <arpa/inet.h> 39 40 #include <a.out.h> 41 #include <dlfcn.h> 42 #include <err.h> 43 #include <fcntl.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <unistd.h> 47 48 #include "extern.h" 49 50 static void 51 usage(void) 52 { 53 fprintf(stderr, "usage: ldd [-a] [-v] [-f format] program ...\n"); 54 exit(1); 55 } 56 57 int 58 main(int argc, char *argv[]) 59 { 60 char *fmt1 = NULL, *fmt2 = NULL; 61 int rval; 62 int c; 63 int aflag, vflag; 64 65 aflag = vflag = 0; 66 67 while ((c = getopt(argc, argv, "avf:")) != -1) { 68 switch (c) { 69 case 'a': 70 aflag++; 71 break; 72 case 'v': 73 vflag++; 74 break; 75 case 'f': 76 if (fmt1) { 77 if (fmt2) 78 errx(1, "too many formats"); 79 fmt2 = optarg; 80 } else 81 fmt1 = optarg; 82 break; 83 default: 84 usage(); 85 /*NOTREACHED*/ 86 } 87 } 88 argc -= optind; 89 argv += optind; 90 91 if (vflag && fmt1) 92 errx(1, "-v may not be used with -f"); 93 94 if (argc <= 0) { 95 usage(); 96 /*NOTREACHED*/ 97 } 98 99 #ifdef __i386__ 100 if (vflag) { 101 for (c = 0; c < argc; c++) 102 dump_file(argv[c]); 103 exit(error_count == 0 ? EXIT_SUCCESS : EXIT_FAILURE); 104 } 105 #endif 106 107 /* ld.so magic */ 108 setenv("LD_TRACE_LOADED_OBJECTS", "yes", 1); 109 if (fmt1) 110 setenv("LD_TRACE_LOADED_OBJECTS_FMT1", fmt1, 1); 111 if (fmt2) 112 setenv("LD_TRACE_LOADED_OBJECTS_FMT2", fmt2, 1); 113 114 rval = 0; 115 for ( ; argc > 0; argc--, argv++) { 116 int fd; 117 union { 118 struct exec aout; 119 Elf_Ehdr elf; 120 } hdr; 121 int n; 122 int status; 123 int file_ok; 124 int is_shlib; 125 126 if ((fd = open(*argv, O_RDONLY, 0)) < 0) { 127 warn("%s", *argv); 128 rval |= 1; 129 continue; 130 } 131 if ((n = read(fd, &hdr, sizeof hdr)) == -1) { 132 warn("%s: can't read program header", *argv); 133 (void)close(fd); 134 rval |= 1; 135 continue; 136 } 137 138 file_ok = 1; 139 is_shlib = 0; 140 if ((size_t)n >= sizeof hdr.aout && !N_BADMAG(hdr.aout)) { 141 /* a.out file */ 142 if ((N_GETFLAG(hdr.aout) & EX_DPMASK) != EX_DYNAMIC 143 #if 1 /* Compatibility */ 144 || hdr.aout.a_entry < __LDPGSZ 145 #endif 146 ) { 147 warnx("%s: not a dynamic executable", *argv); 148 file_ok = 0; 149 } 150 } else if ((size_t)n >= sizeof hdr.elf && IS_ELF(hdr.elf)) { 151 Elf_Ehdr ehdr; 152 Elf_Phdr phdr; 153 int dynamic = 0, i; 154 155 if (lseek(fd, 0, SEEK_SET) == -1 || 156 read(fd, &ehdr, sizeof ehdr) != sizeof ehdr || 157 lseek(fd, ehdr.e_phoff, SEEK_SET) == -1 158 ) { 159 warnx("%s: can't read program header", *argv); 160 file_ok = 0; 161 } else { 162 for (i = 0; i < ehdr.e_phnum; i++) { 163 if (read(fd, &phdr, ehdr.e_phentsize) 164 != sizeof phdr) { 165 warnx("%s: can't read program header", 166 *argv); 167 file_ok = 0; 168 break; 169 } 170 if (phdr.p_type == PT_DYNAMIC) 171 dynamic = 1; 172 } 173 } 174 if (!dynamic) { 175 warnx("%s: not a dynamic executable", *argv); 176 file_ok = 0; 177 } else if (hdr.elf.e_type == ET_DYN) { 178 if (hdr.elf.e_ident[EI_OSABI] & ELFOSABI_FREEBSD) { 179 is_shlib = 1; 180 } else { 181 warnx("%s: not a FreeBSD ELF shared " 182 "object", *argv); 183 file_ok = 0; 184 } 185 } 186 } else { 187 warnx("%s: not a dynamic executable", *argv); 188 file_ok = 0; 189 } 190 (void)close(fd); 191 if (!file_ok) { 192 rval |= 1; 193 continue; 194 } 195 196 setenv("LD_TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1); 197 if (aflag) setenv("LD_TRACE_LOADED_OBJECTS_ALL", "1", 1); 198 else if (fmt1 == NULL && fmt2 == NULL) 199 /* Default formats */ 200 printf("%s:\n", *argv); 201 202 fflush(stdout); 203 204 switch (fork()) { 205 case -1: 206 err(1, "fork"); 207 break; 208 default: 209 if (wait(&status) <= 0) { 210 warn("wait"); 211 rval |= 1; 212 } else if (WIFSIGNALED(status)) { 213 fprintf(stderr, "%s: signal %d\n", 214 *argv, WTERMSIG(status)); 215 rval |= 1; 216 } else if (WIFEXITED(status) && WEXITSTATUS(status)) { 217 fprintf(stderr, "%s: exit status %d\n", 218 *argv, WEXITSTATUS(status)); 219 rval |= 1; 220 } 221 break; 222 case 0: 223 if (is_shlib == 0) { 224 execl(*argv, *argv, (char *)NULL); 225 warn("%s", *argv); 226 } else { 227 dlopen(*argv, RTLD_TRACE); 228 warnx("%s: %s", *argv, dlerror()); 229 } 230 _exit(1); 231 } 232 } 233 234 return rval; 235 } 236