xref: /dragonfly/usr.sbin/resident/resident.c (revision 2ee85085) 
1 /*
2  * Copyright (c) 2003 Matthew Dillon <dillon@backplane.com>
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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $DragonFly: src/usr.sbin/resident/resident.c,v 1.8 2005/04/22 16:59:46 liamfoy Exp $
27  */
28 
29 #include <sys/cdefs.h>
30 
31 #include <sys/param.h>
32 #include <sys/wait.h>
33 #include <sys/stat.h>
34 #include <sys/resident.h>
35 #include <sys/sysctl.h>
36 
37 #include <machine/elf.h>
38 #include <a.out.h>
39 #include <dlfcn.h>
40 #include <err.h>
41 #include <fcntl.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <unistd.h>
45 #include <string.h>
46 #include <errno.h>
47 
48 static void
49 usage(void)
50 {
51 	fprintf(stderr, "usage: resident [-l] [-f] [-x id] [-d] [-R] program ...\n");
52 	exit(1);
53 }
54 
55 static int
56 list_residents(void)
57 {
58 	const char *mib = "vm.resident";
59 	struct xresident *buf;
60 	int res_count, res_total;
61 	int error, i;
62 
63 	/* get the number of resident binaries */
64 	error = sysctlbyname(mib, NULL, &res_count, NULL, 0);
65 	if (error != 0) {
66 		perror("sysctl: vm.resident");
67 		goto done;
68 	}
69 
70 	if (res_count == 0) {
71 		printf("no resident binaries to list\n");
72 		goto done;
73 	}
74 
75 	/* allocate memory for the list of binaries */
76 	res_total = sizeof(*buf) * res_count;
77 	if ((buf = malloc(res_total)) != NULL) {
78 		/* retrieve entries via sysctl */
79 		error = sysctlbyname(mib, buf, &res_total, NULL, 0);
80 		if (error != 0) {
81 			perror("sysctl: vm.resident");
82 			goto done;
83 		}
84 	} else {
85 		perror("malloc");
86 		goto done;
87 	}
88 
89 	/* print the list of retrieved resident binary */
90 	printf("%-4s\t%-15s\t%-12s\t%-30s\n","Id", "Size", "Address", "Executable");
91 	for (i = 0; i < res_count; ++i) {
92 		printf("%-4d\t%-15lld\t0x%-12x\t%-30s\n",
93 			buf[i].res_id,
94 			buf[i].res_stat.st_size,
95 			buf[i].res_entry_addr,
96 			buf[i].res_file);
97 	}
98 
99 	/* free back the memory */
100 	free(buf);
101 
102 done:
103 	return error;
104 }
105 
106 int
107 main(int argc, char *argv[])
108 {
109 	int	rval;
110 	int	c;
111 	int	doreg = 1;
112 	int	force = 0;
113 
114 	while ((c = getopt(argc, argv, "Rdflx:")) != -1) {
115 		switch (c) {
116 		case 'f':
117 			force = 1;
118 			break;
119 		case 'l':
120 			rval = list_residents();
121 			if (rval < 0)
122 				exit(EXIT_FAILURE);
123 			else
124 				exit(EXIT_SUCCESS);
125 		case 'd':
126 			doreg = 0;
127 			break;
128 		case 'x':
129 		case 'R':
130 			if (c == 'R')
131 			    c = exec_sys_unregister(-2);
132 			else
133 			    c = exec_sys_unregister(strtol(optarg, NULL, 0));
134 			if (c < 0)
135 			    printf("unregister: %s\n", strerror(errno));
136 			else
137 			    printf("unregister: success\n");
138 			exit(0);
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 	/* ld-elf.so magic */
153 	if (doreg) {
154 	    if (setenv("LD_RESIDENT_REGISTER_NOW", "yes", 1) == -1)
155 			err(1, "setenv failed");
156 	} else {
157 	    if (setenv("LD_RESIDENT_UNREGISTER_NOW", "yes", 1) == -1)
158 			err(1, "setenv failed");
159 	}
160 
161 	rval = 0;
162 	for ( ;  argc > 0;  argc--, argv++) {
163 		int	fd;
164 		union {
165 			struct exec aout;
166 			Elf_Ehdr elf;
167 		} hdr;
168 		int	n;
169 		int	status;
170 		int	file_ok;
171 		int	is_shlib;
172 
173 		if (force)
174 			goto force_target;
175 
176 		if ((fd = open(*argv, O_RDONLY, 0)) < 0) {
177 			warn("%s", *argv);
178 			rval |= 1;
179 			continue;
180 		}
181 		if ((n = read(fd, &hdr, sizeof hdr)) == -1) {
182 			warn("%s: can't read program header", *argv);
183 			close(fd);
184 			rval |= 1;
185 			continue;
186 		}
187 
188 		file_ok = 1;
189 		is_shlib = 0;
190 		if ((size_t)n >= sizeof hdr.aout && !N_BADMAG(hdr.aout)) {
191 			/* a.out file */
192 			if ((N_GETFLAG(hdr.aout) & EX_DPMASK) != EX_DYNAMIC
193 #if 1 /* Compatibility */
194 			    || hdr.aout.a_entry < __LDPGSZ
195 #endif
196 				) {
197 				warnx("%s: not a dynamic executable", *argv);
198 				file_ok = 0;
199 			}
200 		} else if ((size_t)n >= sizeof hdr.elf && IS_ELF(hdr.elf)) {
201 			Elf_Ehdr ehdr;
202 			Elf_Phdr phdr;
203 			int dynamic = 0, i;
204 
205 			if (lseek(fd, 0, SEEK_SET) == -1 ||
206 			    read(fd, &ehdr, sizeof ehdr) != sizeof ehdr ||
207 			    lseek(fd, ehdr.e_phoff, SEEK_SET) == -1
208 			   ) {
209 				warnx("%s: can't read program header", *argv);
210 				file_ok = 0;
211 			} else {
212 				for (i = 0; i < ehdr.e_phnum; i++) {
213 					if (read(fd, &phdr, ehdr.e_phentsize)
214 					   != sizeof phdr) {
215 						warnx("%s: can't read program header",
216 						    *argv);
217 						file_ok = 0;
218 						break;
219 					}
220 					if (phdr.p_type == PT_DYNAMIC)
221 						dynamic = 1;
222 				}
223 			}
224 			if (!dynamic) {
225 				warnx("%s: not a dynamic executable", *argv);
226 				file_ok = 0;
227 			} else if (hdr.elf.e_type == ET_DYN) {
228 				if (hdr.elf.e_ident[EI_OSABI] & ELFOSABI_FREEBSD) {
229 					is_shlib = 1;
230 				} else {
231 					warnx("%s: not a FreeBSD ELF shared "
232 					      "object", *argv);
233 					file_ok = 0;
234 				}
235 			}
236 		} else {
237 			warnx("%s: not a dynamic executable", *argv);
238 			file_ok = 0;
239 		}
240 		close(fd);
241 		if (!file_ok) {
242 			rval |= 1;
243 			continue;
244 		}
245 
246 		if (is_shlib) {
247 			rval |= 1;
248 			warnx("%s: resident not supported on shared libraries.", *argv);
249 			continue;
250 		}
251 
252 force_target:
253 		fflush(stdout);
254 
255 		switch (fork()) {
256 		case -1:
257 			err(1, "fork");
258 			break;
259 		default:
260 			if (wait(&status) <= 0) {
261 				warn("wait");
262 				rval |= 1;
263 			} else if (WIFSIGNALED(status)) {
264 				fprintf(stderr, "%s: signal %d\n",
265 						*argv, WTERMSIG(status));
266 				rval |= 1;
267 			} else if (WIFEXITED(status) && WEXITSTATUS(status)) {
268 				switch(WEXITSTATUS(status)) {
269 				case ENOENT:
270 				    fprintf(stderr, "%s: entry not found\n",
271 					*argv);
272 				    break;
273 				case EEXIST:
274 				    fprintf(stderr, "%s: binary already resident\n",
275 					*argv);
276 				    break;
277 				default:
278 				    fprintf(stderr, "%s: exit status %s\n",
279 						*argv, strerror(WEXITSTATUS(status)));
280 				}
281 				rval |= 1;
282 			} else {
283 			}
284 			break;
285 		case 0:
286 			execl(*argv, *argv, (char *)NULL);
287 			warn("%s", *argv);
288 			_exit(1);
289 		}
290 	}
291 
292 	return rval;
293 }
294