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 <dlfcn.h> 38 #include <err.h> 39 #include <fcntl.h> 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <unistd.h> 43 44 static void usage(void); 45 46 static void 47 usage(void) 48 { 49 fprintf(stderr, "usage: ldd [-av] [-f format] program ...\n"); 50 exit(1); 51 } 52 53 int 54 main(int argc, char **argv) 55 { 56 char *fmt1 = NULL, *fmt2 = NULL; 57 int rval; 58 int c; 59 int aflag; 60 61 aflag = 0; 62 while ((c = getopt(argc, argv, "af:v")) != -1) { 63 switch (c) { 64 case 'a': 65 aflag++; 66 break; 67 case 'f': 68 if (fmt1) { 69 if (fmt2) 70 errx(1, "too many formats"); 71 fmt2 = optarg; 72 } else 73 fmt1 = optarg; 74 break; 75 case 'v': 76 break; 77 default: 78 usage(); 79 /* NOTREACHED */ 80 } 81 } 82 argc -= optind; 83 argv += optind; 84 85 if (argc <= 0) { 86 usage(); 87 /* NOTREACHED */ 88 } 89 90 /* ld.so magic */ 91 if (setenv("LD_TRACE_LOADED_OBJECTS", "yes", 1) == -1) 92 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS=1"); 93 if (fmt1) { 94 if (setenv("LD_TRACE_LOADED_OBJECTS_FMT1", fmt1, 1) == -1) 95 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_FMT1=%s", fmt1); 96 } 97 if (fmt2) { 98 if (setenv("LD_TRACE_LOADED_OBJECTS_FMT2", fmt2, 1) == -1) 99 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_FMT2=%s", fmt2); 100 } 101 102 rval = 0; 103 for ( ; argc > 0; argc--, argv++) { 104 int fd; 105 union { 106 Elf_Ehdr elf; 107 } hdr; 108 ssize_t n; 109 int status; 110 int file_ok; 111 int is_shlib; 112 113 if ((fd = open(*argv, O_RDONLY, 0)) < 0) { 114 warn("%s", *argv); 115 rval |= 1; 116 continue; 117 } 118 if ((n = read(fd, &hdr, sizeof hdr)) == -1) { 119 warn("%s: can't read program header", *argv); 120 close(fd); 121 rval |= 1; 122 continue; 123 } 124 125 file_ok = 1; 126 is_shlib = 0; 127 if ((size_t)n >= sizeof hdr.elf && IS_ELF(hdr.elf)) { 128 Elf_Ehdr ehdr; 129 Elf_Phdr phdr; 130 int dynamic = 0, i; 131 132 if (lseek(fd, 0, SEEK_SET) == -1 || 133 read(fd, &ehdr, sizeof ehdr) != sizeof ehdr || 134 lseek(fd, ehdr.e_phoff, SEEK_SET) == -1 135 ) { 136 warnx("%s: can't read program header", *argv); 137 file_ok = 0; 138 } else { 139 for (i = 0; i < ehdr.e_phnum; i++) { 140 if (read(fd, &phdr, ehdr.e_phentsize) 141 != sizeof phdr) { 142 warnx("%s: can't read program header", 143 *argv); 144 file_ok = 0; 145 break; 146 } 147 if (phdr.p_type == PT_DYNAMIC) 148 dynamic = 1; 149 } 150 } 151 if (!dynamic) { 152 warnx("%s: not a dynamic executable", *argv); 153 file_ok = 0; 154 } else if (hdr.elf.e_type == ET_DYN) { 155 is_shlib = 1; 156 } 157 } else { 158 warnx("%s: not a dynamic executable", *argv); 159 file_ok = 0; 160 } 161 close(fd); 162 if (!file_ok) { 163 rval |= 1; 164 continue; 165 } 166 167 if (setenv("LD_TRACE_LOADED_OBJECTS_PROGNAME", *argv, 1) == -1) 168 err(1, "setenv: cannot set LD_TRACE_LOADED_OBJECTS_PROGNAME=%s", *argv); 169 if (aflag) setenv("LD_TRACE_LOADED_OBJECTS_ALL", "1", 1); 170 else if (fmt1 == NULL && fmt2 == NULL) 171 /* Default formats */ 172 printf("%s:\n", *argv); 173 fflush(stdout); 174 175 switch (fork()) { 176 case -1: 177 err(1, "fork"); 178 break; 179 default: 180 if (wait(&status) <= 0) { 181 warn("wait"); 182 rval |= 1; 183 } else if (WIFSIGNALED(status)) { 184 fprintf(stderr, "%s: signal %d\n", 185 *argv, WTERMSIG(status)); 186 rval |= 1; 187 } else if (WIFEXITED(status) && WEXITSTATUS(status)) { 188 fprintf(stderr, "%s: exit status %d\n", 189 *argv, WEXITSTATUS(status)); 190 rval |= 1; 191 } 192 break; 193 case 0: 194 if (is_shlib == 0) { 195 execl(*argv, *argv, NULL); 196 warn("%s", *argv); 197 } else { 198 dlopen(*argv, RTLD_TRACE); 199 warnx("%s: %s", *argv, dlerror()); 200 } 201 _exit(1); 202 } 203 } 204 205 return rval; 206 } 207