xref: /netbsd-src/usr.bin/ldd/ldd.c (revision 4e6df137e8e14049b5a701d249962c480449c141)
1 /*	$NetBSD: ldd.c,v 1.14 2010/02/27 11:17:05 roy 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 1.14 2010/02/27 11:17:05 roy 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 Obj_Entry *_rtld_objlist;	/* Head of linked list of shared objects */
93 Obj_Entry **_rtld_objtail = &_rtld_objlist;
94 				/* Link field of last object in list */
95 int _rtld_objcount;		/* Number of shared objects */
96 Obj_Entry *_rtld_objmain;	/* The main program shared object */
97 size_t _rtld_pagesz;
98 
99 Search_Path *_rtld_default_paths;
100 Search_Path *_rtld_paths;
101 Library_Xform *_rtld_xforms;
102 
103 static void usage(void) __dead;
104 char *main_local;
105 char *main_progname;
106 
107 static void
108 usage(void)
109 {
110 	fprintf(stderr, "Usage: %s [-f <format 1>] [-f <format 2>] <filename>"
111 		" ...\n", getprogname());
112 	exit(1);
113 }
114 
115 int
116 main(int argc, char **argv)
117 {
118 	const char *fmt1 = NULL, *fmt2 = NULL;
119 	int c;
120 
121 #ifdef DEBUG
122 	debug = 1;
123 #endif
124 	while ((c = getopt(argc, argv, "f:o")) != -1) {
125 		switch (c) {
126 		case 'f':
127 			if (fmt1) {
128 				if (fmt2)
129 					errx(1, "Too many formats");
130 				fmt2 = optarg;
131 			} else
132 				fmt1 = optarg;
133 			break;
134 		case 'o':
135 			if (fmt1 || fmt2)
136 				errx(1, "Cannot use -o and -f together");
137 			fmt1 = "%a:-l%o.%m => %p\n";
138 			break;
139 		default:
140 			usage();
141 			/*NOTREACHED*/
142 		}
143 	}
144 	argc -= optind;
145 	argv += optind;
146 
147 	if (argc <= 0) {
148 		usage();
149 		/*NOTREACHED*/
150 	}
151 
152 	for (; argc != 0; argc--, argv++) {
153 		int fd;
154 
155 		fd = open(*argv, O_RDONLY);
156 		if (fd == -1) {
157 			warn("%s", *argv);
158 			continue;
159 		}
160 		if (elf_ldd(fd, *argv, fmt1, fmt2) == -1
161 		    /* Alpha never had 32 bit support. */
162 #if defined(_LP64) && !defined(__alpha__)
163 		    && elf32_ldd(fd, *argv, fmt1, fmt2) == -1
164 #ifdef __mips__
165 		    && elf32_ldd_compat(fd, *argv, fmt1, fmt2) == -1
166 #endif
167 #endif
168 		    )
169 			warnx("%s", error_message);
170 		close(fd);
171 	}
172 
173 	return 0;
174 }
175 
176 /*
177  * Error reporting function.  Use it like printf.  If formats the message
178  * into a buffer, and sets things up so that the next call to dlerror()
179  * will return the message.
180  */
181 void
182 _rtld_error(const char *fmt, ...)
183 {
184 	static char buf[512];
185 	va_list ap;
186 	va_start(ap, fmt);
187 	xvsnprintf(buf, sizeof buf, fmt, ap);
188 	error_message = buf;
189 	va_end(ap);
190 }
191 
192 char *
193 dlerror()
194 {
195 	char *msg = error_message;
196 	error_message = NULL;
197 	return msg;
198 }
199 
200 void
201 fmtprint(const char *libname, Obj_Entry *obj, const char *fmt1,
202     const char *fmt2)
203 {
204 	const char *libpath = obj ? obj->path : "not found";
205 	char libnamebuf[200];
206 	char *libmajor = NULL;
207 	const char *fmt;
208 	char *cp;
209 	int c;
210 
211 	if (strncmp(libname, "lib", 3) == 0 &&
212 	    (cp = strstr(libname, ".so")) != NULL) {
213 		int i = cp - (libname + 3);
214 
215 		if (i >= sizeof(libnamebuf))
216 			i = sizeof(libnamebuf) - 1;
217 		(void)memcpy(libnamebuf, libname + 3, i);
218 		libnamebuf[i] = '\0';
219 		if (cp[3] && isdigit((unsigned char)cp[4]))
220 			libmajor = &cp[4];
221 		libname = libnamebuf;
222 	}
223 
224 	if (fmt1 == NULL)
225 		fmt1 = libmajor != NULL ?
226 		    "\t-l%o.%m => %p\n" :
227 		    "\t-l%o => %p\n";
228 	if (fmt2 == NULL)
229 		fmt2 = "\t%o => %p\n";
230 
231 	fmt = libname == libnamebuf ? fmt1 : fmt2;
232 	while ((c = *fmt++) != '\0') {
233 		switch (c) {
234 		default:
235 			putchar(c);
236 			continue;
237 		case '\\':
238 			switch (c = *fmt) {
239 			case '\0':
240 				continue;
241 			case 'n':
242 				putchar('\n');
243 				break;
244 			case 't':
245 				putchar('\t');
246 				break;
247 			}
248 			break;
249 		case '%':
250 			switch (c = *fmt) {
251 			case '\0':
252 				continue;
253 			case '%':
254 			default:
255 				putchar(c);
256 				break;
257 			case 'A':
258 				printf("%s", main_local);
259 				break;
260 			case 'a':
261 				printf("%s", main_progname);
262 				break;
263 			case 'o':
264 				printf("%s", libname);
265 				break;
266 			case 'm':
267 				printf("%s", libmajor);
268 				break;
269 			case 'n':
270 				/* XXX: not supported for elf */
271 				break;
272 			case 'p':
273 				printf("%s", libpath);
274 				break;
275 			case 'x':
276 				printf("%p", obj ? obj->mapbase : 0);
277 				break;
278 			}
279 			break;
280 		}
281 		++fmt;
282 	}
283 }
284 
285 void
286 print_needed(Obj_Entry *obj, const char *fmt1, const char *fmt2)
287 {
288 	const Needed_Entry *needed;
289 
290 	for (needed = obj->needed; needed != NULL; needed = needed->next) {
291 		const char *libname = obj->strtab + needed->name;
292 
293 		if (needed->obj != NULL) {
294 			if (!needed->obj->printed) {
295 				fmtprint(libname, needed->obj, fmt1, fmt2);
296 				needed->obj->printed = 1;
297 				print_needed(needed->obj, fmt1, fmt2);
298 			}
299 		} else {
300 			fmtprint(libname, needed->obj, fmt1, fmt2);
301 		}
302 	}
303 }
304