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 1.3 2004/01/20 21:32:43 dillon Exp $
  27  */
  28
  29 #include <sys/cdefs.h>
  30
  31 #include <sys/param.h>
  32 #include <sys/wait.h>
  33 #include <sys/resident.h>
  34
  35 #include <machine/elf.h>
  36 #include <a.out.h>
  37 #include <dlfcn.h>
  38 #include <err.h>
  39 #include <fcntl.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <unistd.h>
  43 #include <string.h>
  44 #include <errno.h>
  45
  46 static void
  47 usage(void)
  48 {
  49         fprintf(stderr, "usage: resident [-d] program ...\n");
  50         exit(1);
  51 }
  52
  53 int
  54 main(int argc, char *argv[])
  55 {
  56         int     rval;
  57         int     c;
  58         int     doreg = 1;
  59         int     force = 0;
  60
  61         while ((c = getopt(argc, argv, "dfx:")) != -1) {
  62                 switch (c) {
  63                 case 'f':
  64                         force = 1;
  65                         break;
  66                 case 'd':
  67                         doreg = 0;
  68                         break;
  69                 case 'x':
  70                 case 'R':
  71                         if (c == 'x')
  72                             c = exec_sys_unregister(-2);
  73                         else
  74                             c = exec_sys_unregister(strtol(optarg, NULL, 0));
  75                         if (c < 0)
  76                             printf("unregister: %s\n", strerror(errno));
  77                         else
  78                             printf("unregister: success\n");
  79                         exit(0);
  80                 default:
  81                         usage();
  82                         /*NOTREACHED*/
  83                 }
  84         }
  85         argc -= optind;
  86         argv += optind;
  87
  88         if (argc <= 0) {
  89                 usage();
  90                 /*NOTREACHED*/
  91         }
  92
  93         /* ld-elf.so magic */
  94         if (doreg)
  95             setenv("LD_RESIDENT_REGISTER_NOW", "yes", 1);
  96         else
  97             setenv("LD_RESIDENT_UNREGISTER_NOW", "yes", 1);
  98
  99         rval = 0;
 100         for ( ;  argc > 0;  argc--, argv++) {
 101                 int     fd;
 102                 union {
 103                         struct exec aout;
 104                         Elf_Ehdr elf;
 105                 } hdr;
 106                 int     n;
 107                 int     status;
 108                 int     file_ok;
 109                 int     is_shlib;
 110
 111                 if (force)
 112                         goto force_target;
 113
 114                 if ((fd = open(*argv, O_RDONLY, 0)) < 0) {
 115                         warn("%s", *argv);
 116                         rval |= 1;
 117                         continue;
 118                 }
 119                 if ((n = read(fd, &hdr, sizeof hdr)) == -1) {
 120                         warn("%s: can't read program header", *argv);
 121                         (void)close(fd);
 122                         rval |= 1;
 123                         continue;
 124                 }
 125
 126                 file_ok = 1;
 127                 is_shlib = 0;
 128                 if ((size_t)n >= sizeof hdr.aout && !N_BADMAG(hdr.aout)) {
 129                         /* a.out file */
 130                         if ((N_GETFLAG(hdr.aout) & EX_DPMASK) != EX_DYNAMIC
 131 #if 1 /* Compatibility */
 132                             || hdr.aout.a_entry < __LDPGSZ
 133 #endif
 134                                 ) {
 135                                 warnx("%s: not a dynamic executable", *argv);
 136                                 file_ok = 0;
 137                         }
 138                 } else if ((size_t)n >= sizeof hdr.elf && IS_ELF(hdr.elf)) {
 139                         Elf_Ehdr ehdr;
 140                         Elf_Phdr phdr;
 141                         int dynamic = 0, i;
 142
 143                         if (lseek(fd, 0, SEEK_SET) == -1 ||
 144                             read(fd, &ehdr, sizeof ehdr) != sizeof ehdr ||
 145                             lseek(fd, ehdr.e_phoff, SEEK_SET) == -1
 146                            ) {
 147                                 warnx("%s: can't read program header", *argv);
 148                                 file_ok = 0;
 149                         } else {
 150                                 for (i = 0; i < ehdr.e_phnum; i++) {
 151                                         if (read(fd, &phdr, ehdr.e_phentsize)
 152                                            != sizeof phdr) {
 153                                                 warnx("%s: can't read program header",
 154                                                     *argv);
 155                                                 file_ok = 0;
 156                                                 break;
 157                                         }
 158                                         if (phdr.p_type == PT_DYNAMIC)
 159                                                 dynamic = 1;
 160                                 }
 161                         }
 162                         if (!dynamic) {
 163                                 warnx("%s: not a dynamic executable", *argv);
 164                                 file_ok = 0;
 165                         } else if (hdr.elf.e_type == ET_DYN) {
 166                                 if (hdr.elf.e_ident[EI_OSABI] & ELFOSABI_FREEBSD) {
 167                                         is_shlib = 1;
 168                                 } else {
 169                                         warnx("%s: not a FreeBSD ELF shared "
 170                                               "object", *argv);
 171                                         file_ok = 0;
 172                                 }
 173                         }
 174                 } else {
 175                         warnx("%s: not a dynamic executable", *argv);
 176                         file_ok = 0;
 177                 }
 178                 (void)close(fd);
 179                 if (!file_ok) {
 180                         rval |= 1;
 181                         continue;
 182                 }
 183
 184                 if (is_shlib) {
 185                         rval |= 1;
 186                         warnx("%s: resident not supported on shared libraries.", *argv);
 187                         continue;
 188                 }
 189
 190 force_target:
 191                 fflush(stdout);
 192
 193                 switch (fork()) {
 194                 case -1:
 195                         err(1, "fork");
 196                         break;
 197                 default:
 198                         if (wait(&status) <= 0) {
 199                                 warn("wait");
 200                                 rval |= 1;
 201                         } else if (WIFSIGNALED(status)) {
 202                                 fprintf(stderr, "%s: signal %d\n",
 203                                                 *argv, WTERMSIG(status));
 204                                 rval |= 1;
 205                         } else if (WIFEXITED(status) && WEXITSTATUS(status)) {
 206                                 switch(WEXITSTATUS(status)) {
 207                                 case ENOENT:
 208                                     fprintf(stderr, "%s: entry not found\n",
 209                                         *argv);
 210                                     break;
 211                                 case EEXIST:
 212                                     fprintf(stderr, "%s: binary already resident\n",
 213                                         *argv);
 214                                     break;
 215                                 default:
 216                                     fprintf(stderr, "%s: exit status %s\n",
 217                                                 *argv, strerror(WEXITSTATUS(status)));
 218                                 }
 219                                 rval |= 1;
 220                         } else {
 221                         }
 222                         break;
 223                 case 0:
 224                         execl(*argv, *argv, (char *)NULL);
 225                         warn("%s", *argv);
 226                         _exit(1);
 227                 }
 228         }
 229
 230         return rval;
 231 }