xref: /dragonfly/usr.sbin/resident/resident.c (revision c9f721c2) 
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 1.6 2004/06/04 17:30:26 hmp 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 	    setenv("LD_RESIDENT_REGISTER_NOW", "yes", 1);
155 	else
156 	    setenv("LD_RESIDENT_UNREGISTER_NOW", "yes", 1);
157 
158 	rval = 0;
159 	for ( ;  argc > 0;  argc--, argv++) {
160 		int	fd;
161 		union {
162 			struct exec aout;
163 			Elf_Ehdr elf;
164 		} hdr;
165 		int	n;
166 		int	status;
167 		int	file_ok;
168 		int	is_shlib;
169 
170 		if (force)
171 			goto force_target;
172 
173 		if ((fd = open(*argv, O_RDONLY, 0)) < 0) {
174 			warn("%s", *argv);
175 			rval |= 1;
176 			continue;
177 		}
178 		if ((n = read(fd, &hdr, sizeof hdr)) == -1) {
179 			warn("%s: can't read program header", *argv);
180 			(void)close(fd);
181 			rval |= 1;
182 			continue;
183 		}
184 
185 		file_ok = 1;
186 		is_shlib = 0;
187 		if ((size_t)n >= sizeof hdr.aout && !N_BADMAG(hdr.aout)) {
188 			/* a.out file */
189 			if ((N_GETFLAG(hdr.aout) & EX_DPMASK) != EX_DYNAMIC
190 #if 1 /* Compatibility */
191 			    || hdr.aout.a_entry < __LDPGSZ
192 #endif
193 				) {
194 				warnx("%s: not a dynamic executable", *argv);
195 				file_ok = 0;
196 			}
197 		} else if ((size_t)n >= sizeof hdr.elf && IS_ELF(hdr.elf)) {
198 			Elf_Ehdr ehdr;
199 			Elf_Phdr phdr;
200 			int dynamic = 0, i;
201 
202 			if (lseek(fd, 0, SEEK_SET) == -1 ||
203 			    read(fd, &ehdr, sizeof ehdr) != sizeof ehdr ||
204 			    lseek(fd, ehdr.e_phoff, SEEK_SET) == -1
205 			   ) {
206 				warnx("%s: can't read program header", *argv);
207 				file_ok = 0;
208 			} else {
209 				for (i = 0; i < ehdr.e_phnum; i++) {
210 					if (read(fd, &phdr, ehdr.e_phentsize)
211 					   != sizeof phdr) {
212 						warnx("%s: can't read program header",
213 						    *argv);
214 						file_ok = 0;
215 						break;
216 					}
217 					if (phdr.p_type == PT_DYNAMIC)
218 						dynamic = 1;
219 				}
220 			}
221 			if (!dynamic) {
222 				warnx("%s: not a dynamic executable", *argv);
223 				file_ok = 0;
224 			} else if (hdr.elf.e_type == ET_DYN) {
225 				if (hdr.elf.e_ident[EI_OSABI] & ELFOSABI_FREEBSD) {
226 					is_shlib = 1;
227 				} else {
228 					warnx("%s: not a FreeBSD ELF shared "
229 					      "object", *argv);
230 					file_ok = 0;
231 				}
232 			}
233 		} else {
234 			warnx("%s: not a dynamic executable", *argv);
235 			file_ok = 0;
236 		}
237 		(void)close(fd);
238 		if (!file_ok) {
239 			rval |= 1;
240 			continue;
241 		}
242 
243 		if (is_shlib) {
244 			rval |= 1;
245 			warnx("%s: resident not supported on shared libraries.", *argv);
246 			continue;
247 		}
248 
249 force_target:
250 		fflush(stdout);
251 
252 		switch (fork()) {
253 		case -1:
254 			err(1, "fork");
255 			break;
256 		default:
257 			if (wait(&status) <= 0) {
258 				warn("wait");
259 				rval |= 1;
260 			} else if (WIFSIGNALED(status)) {
261 				fprintf(stderr, "%s: signal %d\n",
262 						*argv, WTERMSIG(status));
263 				rval |= 1;
264 			} else if (WIFEXITED(status) && WEXITSTATUS(status)) {
265 				switch(WEXITSTATUS(status)) {
266 				case ENOENT:
267 				    fprintf(stderr, "%s: entry not found\n",
268 					*argv);
269 				    break;
270 				case EEXIST:
271 				    fprintf(stderr, "%s: binary already resident\n",
272 					*argv);
273 				    break;
274 				default:
275 				    fprintf(stderr, "%s: exit status %s\n",
276 						*argv, strerror(WEXITSTATUS(status)));
277 				}
278 				rval |= 1;
279 			} else {
280 			}
281 			break;
282 		case 0:
283 			execl(*argv, *argv, (char *)NULL);
284 			warn("%s", *argv);
285 			_exit(1);
286 		}
287 	}
288 
289 	return rval;
290 }
291