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 */ 32 33 #include <sys/param.h> 34 #include <sys/wait.h> 35 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 static void usage(void); 46 47 static void 48 usage(void) 49 { 50 fprintf(stderr, "usage: ldd [-av] [-f format] program ...\n"); 51 exit(1); 52 } 53 54 int 55 main(int argc, char **argv) 56 { 57 char *fmt1 = NULL, *fmt2 = NULL; 58 int rval; 59 int c; 60 int aflag; 61 62 aflag = 0; 63 while ((c = getopt(argc, argv, "af:v")) != -1) { 64 switch (c) { 65 case 'a': 66 aflag++; 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 case 'v': 77 break; 78 default: 79 usage(); 80 /* NOTREACHED */ 81 } 82 } 83 argc -= optind; 84 argv += optind; 85 86 if (argc <= 0) { 87 usage(); 88 /* NOTREACHED */ 89 } 90 91 /* ld.so magic */ 92 if (setenv("LD_TRACE_LOADED_OBJECTS", "yes", 1) == -1) 93 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS=1"); 94 if (fmt1) { 95 if (setenv("LD_TRACE_LOADED_OBJECTS_FMT1", fmt1, 1) == -1) 96 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_FMT1=%s", fmt1); 97 } 98 if (fmt2) { 99 if (setenv("LD_TRACE_LOADED_OBJECTS_FMT2", fmt2, 1) == -1) 100 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_FMT2=%s", fmt2); 101 } 102 103 rval = 0; 104 for ( ; argc > 0; argc--, argv++) { 105 int fd; 106 union { 107 Elf_Ehdr elf; 108 } hdr; 109 ssize_t n; 110 int status; 111 int file_ok; 112 int is_shlib; 113 114 if ((fd = open(*argv, O_RDONLY, 0)) < 0) { 115 warn("%s", *argv); 116 rval |= 1; 117 continue; 118 } 119 if ((n = read(fd, &hdr, sizeof hdr)) == -1) { 120 warn("%s: can't read program header", *argv); 121 close(fd); 122 rval |= 1; 123 continue; 124 } 125 126 file_ok = 1; 127 is_shlib = 0; 128 if ((size_t)n >= sizeof hdr.elf && IS_ELF(hdr.elf)) { 129 Elf_Ehdr ehdr; 130 Elf_Phdr phdr; 131 int dynamic = 0, i; 132 133 if (lseek(fd, 0, SEEK_SET) == -1 || 134 read(fd, &ehdr, sizeof ehdr) != sizeof ehdr || 135 lseek(fd, ehdr.e_phoff, SEEK_SET) == -1 136 ) { 137 warnx("%s: can't read program header", *argv); 138 file_ok = 0; 139 } else { 140 for (i = 0; i < ehdr.e_phnum; i++) { 141 if (read(fd, &phdr, ehdr.e_phentsize) 142 != sizeof phdr) { 143 warnx("%s: can't read program header", 144 *argv); 145 file_ok = 0; 146 break; 147 } 148 if (phdr.p_type == PT_DYNAMIC) 149 dynamic = 1; 150 } 151 } 152 if (!dynamic) { 153 warnx("%s: not a dynamic executable", *argv); 154 file_ok = 0; 155 } else if (hdr.elf.e_type == ET_DYN) { 156 is_shlib = 1; 157 } 158 } else { 159 warnx("%s: not a dynamic executable", *argv); 160 file_ok = 0; 161 } 162 close(fd); 163 if (!file_ok) { 164 rval |= 1; 165 continue; 166 } 167 168 if (setenv("LD_TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1) == -1) 169 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_PROGNAME=%s", *argv); 170 if (aflag) setenv("LD_TRACE_LOADED_OBJECTS_ALL", "1", 1); 171 else if (fmt1 == NULL && fmt2 == NULL) 172 /* Default formats */ 173 printf("%s:\n", *argv); 174 fflush(stdout); 175 176 switch (fork()) { 177 case -1: 178 err(1, "fork"); 179 break; 180 default: 181 if (wait(&status) <= 0) { 182 warn("wait"); 183 rval |= 1; 184 } else if (WIFSIGNALED(status)) { 185 fprintf(stderr, "%s: signal %d\n", 186 *argv, WTERMSIG(status)); 187 rval |= 1; 188 } else if (WIFEXITED(status) && WEXITSTATUS(status)) { 189 fprintf(stderr, "%s: exit status %d\n", 190 *argv, WEXITSTATUS(status)); 191 rval |= 1; 192 } 193 break; 194 case 0: 195 if (is_shlib == 0) { 196 execl(*argv, *argv, NULL); 197 warn("%s", *argv); 198 } else { 199 dlopen(*argv, RTLD_TRACE); 200 warnx("%s: %s", *argv, dlerror()); 201 } 202 _exit(1); 203 } 204 } 205 206 return rval; 207 } 208