cache_from_tree.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause
   3  *
   4  * Copyright (c) 2022 Cameron Katri.  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  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY CAMERON KATRI AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL CAMERON KATRI OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 #define _XOPEN_SOURCE 500
  29 #include <errno.h>
  30 #include <ftw.h>
  31 #include <stdio.h>
  32 #include <string.h>
  33
  34 #include "trustcache.h"
  35 #include "machoparse/cdhash.h"
  36
  37 static struct trust_cache cache = {};
  38
  39 static int
  40 tccallback(const char *path, const struct stat *sb, __attribute__((unused)) int typeflag, __attribute__((unused)) struct FTW *ftw)
  41 {
  42         if (!S_ISREG(sb->st_mode))
  43                 return 0;
  44
  45         struct cdhashes c = {};
  46         c.count = 0;
  47         find_cdhash(path, sb, &c);
  48
  49         if (c.count == 0)
  50                 return 0;
  51
  52         for (int i = 0; i < c.count; i++) {
  53                 if (cache.version == 0) {
  54                         if ((cache.hashes = realloc(cache.hashes, sizeof(trust_cache_hash0) * (cache.num_entries + 1))) == NULL)
  55                                 exit(1);
  56                         memcpy(cache.hashes[cache.num_entries], c.h[i].cdhash, CS_CDHASH_LEN);
  57                 } else if (cache.version == 1) {
  58                         if ((cache.entries = realloc(cache.entries, sizeof(struct trust_cache_entry1) * (cache.num_entries + 1))) == NULL)
  59                                 exit(1);
  60                         cache.entries[cache.num_entries].hash_type = c.h[i].hash_type;
  61                         cache.entries[cache.num_entries].flags = 0;
  62                         memcpy(cache.entries[cache.num_entries].cdhash, c.h[i].cdhash, CS_CDHASH_LEN);
  63                 }
  64                 cache.num_entries++;
  65         }
  66
  67         free(c.h);
  68
  69         return 0;
  70 }
  71
  72 struct trust_cache
  73 cache_from_tree(const char *path, uint32_t version)
  74 {
  75         struct trust_cache ret = {};
  76         cache.version = version;
  77         cache.num_entries = 0;
  78         ret.version = version;
  79
  80         if (nftw(path, tccallback, 20, 0) == -1) {
  81                 // on macOS, nftw(3) will fail if the path is not a directory, but we don't want that
  82                 if (errno == ENOTDIR) {
  83                         struct stat sb;
  84                         if (stat(path, &sb) == 0 && tccallback(path, &sb, 0, NULL) == 0)
  85                                 goto done;
  86                 }
  87                 perror("nftw");
  88                 return ret;
  89         }
  90
  91 done:
  92         ret.num_entries = cache.num_entries;
  93         ret.hashes = cache.hashes;
  94         return ret;
  95 }