usr.sbin/resident/resident.c

   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 }