tools/release-tools/tar-rootify.c

   1 /*
   2  * Copyright (c) 2002, Stockholms Universitet
   3  * (Stockholm University, Stockholm Sweden)
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the university nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  25  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  31  * POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <sys/types.h>
  35 #include <atypes.h>
  36
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <limits.h>
  40 #include <err.h>
  41 #include <unistd.h>
  42 #include <string.h>
  43
  44 #include "common.h"
  45
  46 /* from gnu tar manual */
  47
  48 struct posix_header
  49 {                               /* byte offset */
  50   char name[100];               /*   0 */
  51   char mode[8];                 /* 100 */
  52   char uid[8];                  /* 108 */
  53   char gid[8];                  /* 116 */
  54   char size[12];                /* 124 */
  55   char mtime[12];               /* 136 */
  56   char chksum[8];               /* 148 */
  57   char typeflag;                /* 156 */
  58   char linkname[100];           /* 157 */
  59   char magic[6];                /* 257 */
  60   char version[2];              /* 263 */
  61   char uname[32];               /* 265 */
  62   char gname[32];               /* 297 */
  63   char devmajor[8];             /* 329 */
  64   char devminor[8];             /* 337 */
  65   char prefix[155];             /* 345 */
  66                                 /* 500 */
  67 };
  68
  69 #define TMAGIC   "ustar"        /* ustar and a null */
  70 #define OLDGNU_MAGIC "ustar  "  /* 7 chars and a null */
  71 #define TMAGLEN  6
  72 #define TVERSION "00"           /* 00 and no null */
  73 #define TVERSLEN 2
  74
  75 int
  76 main(int argc, char **argv)
  77 {
  78     char *buf;
  79     int bufsz = 512;
  80     int i, skip = 0, rec = 0;
  81     struct posix_header *p;
  82     uint64_t size;
  83     unsigned long cksum, hcksum;
  84     int verbose = 0;
  85
  86     buf = malloc(bufsz);
  87     if (buf == NULL)
  88         err(1, "malloc");
  89
  90     while (read(0, buf, bufsz) == bufsz) {
  91         rec++;
  92         p = (void *)buf;
  93
  94         if (skip || p->name[0] == '\0') {
  95             if (write(1, buf, bufsz) != bufsz)
  96                 err(1, "write");
  97             skip--;
  98             continue;
  99         }
 100
 101         if (strcmp(p->magic, TMAGIC) != 0
 102             && strcmp(p->magic, OLDGNU_MAGIC) != 0)
 103             errx(1, "bad magic in #%d  '%.*s'\n", rec,
 104                  (int)sizeof(p->magic), p->magic);
 105
 106         cksum = 256;
 107         for (i = 0; i < sizeof(*p); i++)
 108             if (i < 148 || 155 < i)
 109                 cksum += (u_long)(buf[i] & 0xff);
 110
 111         size = estrntoll(p->size, 12, 8);
 112         if (verbose) {
 113             fprintf(stderr, "rec #%d\n", rec);
 114             fprintf(stderr, "name = %.*s\n", (int)sizeof(p->name), p->name);
 115             fprintf(stderr, "uid = %.*s\n", (int)sizeof(p->uid), p->uid);
 116             fprintf(stderr, "gid = %.*s\n", (int)sizeof(p->gid), p->gid);
 117             fprintf(stderr, "uname = %.*s\n", (int)sizeof(p->uname), p->uname);
 118             fprintf(stderr, "gname = %.*s\n", (int)sizeof(p->gname), p->gname);
 119             fprintf(stderr, "type =     %c\n", p->typeflag);
 120             fprintf(stderr, "size = %.*s\n", (int)sizeof(p->size), p->size);
 121             fprintf(stderr, "size = %llo\n", size);
 122         }
 123
 124         hcksum = estrntoll(p->chksum, 8, 8);
 125         if (hcksum != cksum)
 126             errx(1, "invalid cksum %d != %d", (int)hcksum, (int)cksum);
 127         snprintf(p->uid, (int)sizeof(p->uid), "%6o ", 0);
 128         snprintf(p->gid, (int)sizeof(p->gid), "%6o ", 0);
 129         snprintf(p->uname, (int)sizeof(p->uname), "root");
 130         snprintf(p->gname, (int)sizeof(p->gname), "wheel");
 131
 132         cksum = 256;
 133         for (i = 0; i < sizeof(*p); i++)
 134             if (i < 148 || 155 < i)
 135                 cksum += (u_long)(buf[i] & 0xff);
 136
 137         snprintf(p->chksum, (int)sizeof(p->chksum), " %6o ", (unsigned)cksum);
 138
 139         if (write(1, buf, bufsz) != bufsz)
 140             errx(1, "write");
 141
 142         if (size)
 143             skip = (size + bufsz - 1) / bufsz;
 144     }
 145     return 0;
 146 }