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 * $FreeBSD: src/usr.bin/ldd/ldd.c,v 1.18.2.7 2002/02/27 18:35:53 sobomax Exp $ 31 * $DragonFly: src/usr.bin/ldd/ldd.c,v 1.6 2006/01/12 13:43:11 corecode Exp $ 32 */ 33 34 #include <sys/param.h> 35 #include <sys/wait.h> 36 #include <machine/elf.h> 37 #include <a.out.h> 38 #include <dlfcn.h> 39 #include <err.h> 40 #include <fcntl.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <unistd.h> 44 45 extern void dump_file(const char *); 46 extern int error_count; 47 48 void 49 usage(void) 50 { 51 fprintf(stderr, "usage: ldd [-v] [-f format] program ...\n"); 52 exit(1); 53 } 54 55 int 56 main(int argc, char **argv) 57 { 58 char *fmt1 = NULL, *fmt2 = NULL; 59 int rval; 60 int c; 61 int vflag = 0; 62 63 while ((c = getopt(argc, argv, "vf:")) != -1) { 64 switch (c) { 65 case 'v': 66 vflag++; 67 break; 68 case 'f': 69 if (fmt1) { 70 if (fmt2) 71 errx(1, "too many formats"); 72 fmt2 = optarg; 73 } else 74 fmt1 = optarg; 75 break; 76 default: 77 usage(); 78 /*NOTREACHED*/ 79 } 80 } 81 argc -= optind; 82 argv += optind; 83 84 if (vflag && fmt1) 85 errx(1, "-v may not be used with -f"); 86 87 if (argc <= 0) { 88 usage(); 89 /*NOTREACHED*/ 90 } 91 92 #ifdef __i386__ 93 if (vflag) { 94 for (c = 0; c < argc; c++) 95 dump_file(argv[c]); 96 exit(error_count == 0 ? EXIT_SUCCESS : EXIT_FAILURE); 97 } 98 #endif 99 100 /* ld.so magic */ 101 if (setenv("LD_TRACE_LOADED_OBJECTS", "1", 1) == -1) 102 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS=1"); 103 if (fmt1) { 104 if (setenv("LD_TRACE_LOADED_OBJECTS_FMT1", fmt1, 1) == -1) 105 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_FMT1=%s", fmt1); 106 } 107 if (fmt2) { 108 if (setenv("LD_TRACE_LOADED_OBJECTS_FMT2", fmt2, 1) == -1) 109 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_FMT2=%s", fmt2); 110 } 111 112 rval = 0; 113 for ( ; argc > 0; argc--, argv++) { 114 int fd; 115 union { 116 struct exec aout; 117 Elf_Ehdr elf; 118 } hdr; 119 int n; 120 int status; 121 int file_ok; 122 int is_shlib; 123 124 if ((fd = open(*argv, O_RDONLY, 0)) < 0) { 125 warn("%s", *argv); 126 rval |= 1; 127 continue; 128 } 129 if ((n = read(fd, &hdr, sizeof hdr)) == -1) { 130 warn("%s: can't read program header", *argv); 131 (void)close(fd); 132 rval |= 1; 133 continue; 134 } 135 136 file_ok = 1; 137 is_shlib = 0; 138 if (n >= sizeof hdr.aout && !N_BADMAG(hdr.aout)) { 139 /* a.out file */ 140 if ((N_GETFLAG(hdr.aout) & EX_DPMASK) != EX_DYNAMIC 141 #if 1 /* Compatibility */ 142 || hdr.aout.a_entry < __LDPGSZ 143 #endif 144 ) { 145 warnx("%s: not a dynamic executable", *argv); 146 file_ok = 0; 147 } 148 } else if (n >= sizeof hdr.elf && IS_ELF(hdr.elf)) { 149 Elf_Ehdr ehdr; 150 Elf_Phdr phdr; 151 int dynamic = 0, i; 152 153 if (lseek(fd, 0, SEEK_SET) == -1 || 154 read(fd, &ehdr, sizeof ehdr) != sizeof ehdr || 155 lseek(fd, ehdr.e_phoff, SEEK_SET) == -1 156 ) { 157 warnx("%s: can't read program header", *argv); 158 file_ok = 0; 159 } else { 160 for (i = 0; i < ehdr.e_phnum; i++) { 161 if (read(fd, &phdr, ehdr.e_phentsize) 162 != sizeof phdr) { 163 warnx("%s: can't read program header", 164 *argv); 165 file_ok = 0; 166 break; 167 } 168 if (phdr.p_type == PT_DYNAMIC) 169 dynamic = 1; 170 } 171 } 172 if (!dynamic) { 173 warnx("%s: not a dynamic executable", *argv); 174 file_ok = 0; 175 } else if (hdr.elf.e_type == ET_DYN) { 176 is_shlib = 1; 177 } 178 } else { 179 warnx("%s: not a dynamic executable", *argv); 180 file_ok = 0; 181 } 182 (void)close(fd); 183 if (!file_ok) { 184 rval |= 1; 185 continue; 186 } 187 188 if (setenv("LD_TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1) == -1) 189 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_PROGNAME=%s", *argv); 190 if (fmt1 == NULL && fmt2 == NULL) 191 /* Default formats */ 192 printf("%s:\n", *argv); 193 194 fflush(stdout); 195 196 switch (fork()) { 197 case -1: 198 err(1, "fork"); 199 break; 200 default: 201 if (wait(&status) <= 0) { 202 warn("wait"); 203 rval |= 1; 204 } else if (WIFSIGNALED(status)) { 205 fprintf(stderr, "%s: signal %d\n", 206 *argv, WTERMSIG(status)); 207 rval |= 1; 208 } else if (WIFEXITED(status) && WEXITSTATUS(status)) { 209 fprintf(stderr, "%s: exit status %d\n", 210 *argv, WEXITSTATUS(status)); 211 rval |= 1; 212 } 213 break; 214 case 0: 215 if (is_shlib == 0) { 216 execl(*argv, *argv, (char *)NULL); 217 warn("%s", *argv); 218 } else { 219 dlopen(*argv, RTLD_TRACE); 220 warnx("%s: %s", *argv, dlerror()); 221 } 222 _exit(1); 223 } 224 } 225 226 return rval; 227 } 228