xref: /netbsd-src/usr.bin/ldd/ldd.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: ldd.c,v 1.25 2021/07/23 04:20:05 martin Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Paul Kranenburg.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright 1996 John D. Polstra.
34  * Copyright 1996 Matt Thomas <matt@3am-software.com>
35  * All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. All advertising materials mentioning features or use of this software
46  *    must display the following acknowledgement:
47  *      This product includes software developed by John Polstra.
48  * 4. The name of the author may not be used to endorse or promote products
49  *    derived from this software without specific prior written permission.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
52  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
53  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
54  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
55  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
56  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
60  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61  */
62 
63 #include <sys/cdefs.h>
64 #ifndef lint
65 __RCSID("$NetBSD: ldd.c,v 1.25 2021/07/23 04:20:05 martin Exp $");
66 #endif /* not lint */
67 
68 #include <sys/types.h>
69 #include <sys/mman.h>
70 #include <sys/wait.h>
71 
72 #include <dirent.h>
73 #include <err.h>
74 #include <errno.h>
75 #include <fcntl.h>
76 #include <stdarg.h>
77 #include <stdio.h>
78 #include <stdlib.h>
79 #include <string.h>
80 #include <unistd.h>
81 #include <ctype.h>
82 
83 #include "debug.h"
84 #include "rtld.h"
85 #include "ldd.h"
86 
87 /*
88  * Data declarations.
89  */
90 static char *error_message;	/* Message for dlopen(), or NULL */
91 bool _rtld_trust;		/* False for setuid and setgid programs */
92 /*
93  * This may be ELF64 or ELF32 but since they are used opaquely it doesn't
94  * really matter.
95  */
96 Obj_Entry *_rtld_objlist;	/* Head of linked list of shared objects */
97 Obj_Entry **_rtld_objtail = &_rtld_objlist;
98 				/* Link field of last object in list */
99 u_int _rtld_objcount;		/* Number of shared objects */
100 u_int _rtld_objloads;		/* Number of objects loaded */
101 
102 Obj_Entry *_rtld_objmain;	/* The main program shared object */
103 size_t _rtld_pagesz;
104 
105 Search_Path *_rtld_default_paths;
106 Search_Path *_rtld_paths;
107 Library_Xform *_rtld_xforms;
108 
109 static void usage(void) __dead;
110 char *main_local;
111 char *main_progname;
112 
113 static void
114 usage(void)
115 {
116 	fprintf(stderr, "Usage: %s [-f <format 1>] [-f <format 2>] <filename>"
117 		" ...\n", getprogname());
118 	exit(1);
119 }
120 
121 int
122 main(int argc, char **argv)
123 {
124 	const char *fmt1 = NULL, *fmt2 = NULL;
125 	int c, exit_status = EXIT_SUCCESS;
126 	char cwd[MAXPATHLEN], path[MAXPATHLEN];
127 
128 #ifdef DEBUG
129 	debug = 1;
130 #endif
131 	while ((c = getopt(argc, argv, "f:o")) != -1) {
132 		switch (c) {
133 		case 'f':
134 			if (fmt1) {
135 				if (fmt2)
136 					errx(1, "Too many formats");
137 				fmt2 = optarg;
138 			} else
139 				fmt1 = optarg;
140 			break;
141 		case 'o':
142 			if (fmt1 || fmt2)
143 				errx(1, "Cannot use -o and -f together");
144 			fmt1 = "%a:-l%o.%m => %p\n";
145 			break;
146 		default:
147 			usage();
148 			/*NOTREACHED*/
149 		}
150 	}
151 	argc -= optind;
152 	argv += optind;
153 
154 	if (argc <= 0) {
155 		usage();
156 		/*NOTREACHED*/
157 	}
158 	if (getcwd(cwd, sizeof(cwd)) == NULL)
159 		err(EXIT_FAILURE, "Can't get working directory");
160 
161 	for (; argc != 0; argc--, argv++) {
162 		int fd;
163 
164 		if (**argv != '/') {
165 			strcpy(path, cwd);
166 			strlcat(path, "/", sizeof(path));
167 			strlcat(path, *argv, sizeof(path));
168 		} else {
169 			strlcpy(path, *argv, sizeof(path));
170 		}
171 		fd = open(*argv, O_RDONLY);
172 		if (fd == -1) {
173 			exit_status = EXIT_FAILURE;
174 			warn("%s", *argv);
175 			continue;
176 		}
177 		if (elf_ldd(fd, *argv, path, fmt1, fmt2) == -1
178 		    /* Alpha never had 32 bit support. */
179 #if (defined(_LP64) && !defined(ELF64_ONLY)) || defined(MIPS_N32)
180 		    && elf32_ldd(fd, *argv, path, fmt1, fmt2) == -1
181 #if defined(__mips__) && 0 /* XXX this is still hosed for some reason */
182 		    && elf32_ldd_compat(fd, *argv, path, fmt1, fmt2) == -1
183 #endif
184 #endif
185 		    ) {
186 			exit_status = EXIT_FAILURE;
187 			warnx("%s", error_message);
188 		}
189 		close(fd);
190 	}
191 
192 	return exit_status;
193 }
194 
195 /*
196  * Error reporting function.  Use it like printf.  If formats the message
197  * into a buffer, and sets things up so that the next call to dlerror()
198  * will return the message.
199  */
200 void
201 _rtld_error(const char *fmt, ...)
202 {
203 	static char buf[512];
204 	va_list ap;
205 	va_start(ap, fmt);
206 	xvsnprintf(buf, sizeof buf, fmt, ap);
207 	error_message = buf;
208 	va_end(ap);
209 }
210 
211 char *
212 dlerror()
213 {
214 	char *msg = error_message;
215 	error_message = NULL;
216 	return msg;
217 }
218 
219 void
220 _rtld_die(void)
221 {
222 	const char *msg = dlerror();
223 
224 	if (msg == NULL)
225 		msg = "Fatal error";
226 	xerrx(1, "%s", msg);
227 }
228 
229 void
230 _rtld_shared_enter(void)
231 {
232 }
233 
234 void
235 _rtld_shared_exit(void)
236 {
237 }
238 
239 void
240 _rtld_exclusive_enter(sigset_t *mask)
241 {
242 }
243 
244 void
245 _rtld_exclusive_exit(sigset_t *mask)
246 {
247 }
248