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 1.1 2004/01/20 18:46:22 dillon Exp $
  27  */
  28
  29 #include <sys/cdefs.h>
  30
  31 #include <sys/param.h>
  32 #include <sys/wait.h>
  33
  34 #include <machine/elf.h>
  35 #include <a.out.h>
  36 #include <dlfcn.h>
  37 #include <err.h>
  38 #include <fcntl.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <unistd.h>
  42 #include <string.h>
  43 #include <errno.h>
  44
  45 static void
  46 usage(void)
  47 {
  48         fprintf(stderr, "usage: resident [-d] program ...\n");
  49         exit(1);
  50 }
  51
  52 int
  53 main(int argc, char *argv[])
  54 {
  55         int     rval;
  56         int     c;
  57         int     doreg = 1;
  58         int     force = 0;
  59
  60         while ((c = getopt(argc, argv, "dfx:")) != -1) {
  61                 switch (c) {
  62                 case 'f':
  63                         force = 1;
  64                         break;
  65                 case 'd':
  66                         doreg = 0;
  67                         break;
  68                 case 'x':
  69                         c = exec_sys_unregister(strtol(optarg, NULL, 0));
  70                         if (c < 0)
  71                             printf("unregister: %s\n", strerror(errno));
  72                         else
  73                             printf("unregister: success\n");
  74                         exit(0);
  75                 default:
  76                         usage();
  77                         /*NOTREACHED*/
  78                 }
  79         }
  80         argc -= optind;
  81         argv += optind;
  82
  83         if (argc <= 0) {
  84                 usage();
  85                 /*NOTREACHED*/
  86         }
  87
  88         /* ld-elf.so magic */
  89         if (doreg)
  90             setenv("LD_RESIDENT_REGISTER_NOW", "yes", 1);
  91         else
  92             setenv("LD_RESIDENT_UNREGISTER_NOW", "yes", 1);
  93
  94         rval = 0;
  95         for ( ;  argc > 0;  argc--, argv++) {
  96                 int     fd;
  97                 union {
  98                         struct exec aout;
  99                         Elf_Ehdr elf;
 100                 } hdr;
 101                 int     n;
 102                 int     status;
 103                 int     file_ok;
 104                 int     is_shlib;
 105
 106                 if (force)
 107                         goto force_target;
 108
 109                 if ((fd = open(*argv, O_RDONLY, 0)) < 0) {
 110                         warn("%s", *argv);
 111                         rval |= 1;
 112                         continue;
 113                 }
 114                 if ((n = read(fd, &hdr, sizeof hdr)) == -1) {
 115                         warn("%s: can't read program header", *argv);
 116                         (void)close(fd);
 117                         rval |= 1;
 118                         continue;
 119                 }
 120
 121                 file_ok = 1;
 122                 is_shlib = 0;
 123                 if ((size_t)n >= sizeof hdr.aout && !N_BADMAG(hdr.aout)) {
 124                         /* a.out file */
 125                         if ((N_GETFLAG(hdr.aout) & EX_DPMASK) != EX_DYNAMIC
 126 #if 1 /* Compatibility */
 127                             || hdr.aout.a_entry < __LDPGSZ
 128 #endif
 129                                 ) {
 130                                 warnx("%s: not a dynamic executable", *argv);
 131                                 file_ok = 0;
 132                         }
 133                 } else if ((size_t)n >= sizeof hdr.elf && IS_ELF(hdr.elf)) {
 134                         Elf_Ehdr ehdr;
 135                         Elf_Phdr phdr;
 136                         int dynamic = 0, i;
 137
 138                         if (lseek(fd, 0, SEEK_SET) == -1 ||
 139                             read(fd, &ehdr, sizeof ehdr) != sizeof ehdr ||
 140                             lseek(fd, ehdr.e_phoff, SEEK_SET) == -1
 141                            ) {
 142                                 warnx("%s: can't read program header", *argv);
 143                                 file_ok = 0;
 144                         } else {
 145                                 for (i = 0; i < ehdr.e_phnum; i++) {
 146                                         if (read(fd, &phdr, ehdr.e_phentsize)
 147                                            != sizeof phdr) {
 148                                                 warnx("%s: can't read program header",
 149                                                     *argv);
 150                                                 file_ok = 0;
 151                                                 break;
 152                                         }
 153                                         if (phdr.p_type == PT_DYNAMIC)
 154                                                 dynamic = 1;
 155                                 }
 156                         }
 157                         if (!dynamic) {
 158                                 warnx("%s: not a dynamic executable", *argv);
 159                                 file_ok = 0;
 160                         } else if (hdr.elf.e_type == ET_DYN) {
 161                                 if (hdr.elf.e_ident[EI_OSABI] & ELFOSABI_FREEBSD) {
 162                                         is_shlib = 1;
 163                                 } else {
 164                                         warnx("%s: not a FreeBSD ELF shared "
 165                                               "object", *argv);
 166                                         file_ok = 0;
 167                                 }
 168                         }
 169                 } else {
 170                         warnx("%s: not a dynamic executable", *argv);
 171                         file_ok = 0;
 172                 }
 173                 (void)close(fd);
 174                 if (!file_ok) {
 175                         rval |= 1;
 176                         continue;
 177                 }
 178
 179                 if (is_shlib) {
 180                         rval |= 1;
 181                         warnx("%s: prebinding not supported on shared libraries.", *argv);
 182                         continue;
 183                 }
 184
 185 force_target:
 186                 fflush(stdout);
 187
 188                 switch (fork()) {
 189                 case -1:
 190                         err(1, "fork");
 191                         break;
 192                 default:
 193                         if (wait(&status) <= 0) {
 194                                 warn("wait");
 195                                 rval |= 1;
 196                         } else if (WIFSIGNALED(status)) {
 197                                 fprintf(stderr, "%s: signal %d\n",
 198                                                 *argv, WTERMSIG(status));
 199                                 rval |= 1;
 200                         } else if (WIFEXITED(status) && WEXITSTATUS(status)) {
 201                                 switch(WEXITSTATUS(status)) {
 202                                 case ENOENT:
 203                                     fprintf(stderr, "%s: entry not found\n",
 204                                         *argv);
 205                                     break;
 206                                 case EEXIST:
 207                                     fprintf(stderr, "%s: binary already resident\n",
 208                                         *argv);
 209                                     break;
 210                                 default:
 211                                     fprintf(stderr, "%s: exit status %s\n",
 212                                                 *argv, strerror(WEXITSTATUS(status)));
 213                                 }
 214                                 rval |= 1;
 215                         } else {
 216                         }
 217                         break;
 218                 case 0:
 219                         execl(*argv, *argv, (char *)NULL);
 220                         warn("%s", *argv);
 221                         _exit(1);
 222                 }
 223         }
 224
 225         return rval;
 226 }