1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/*
* Copyright (c) 2014
* Canonical, Ltd. (All rights reserved)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, contact Novell, Inc. or Canonical
* Ltd.
*/
#include <ctype.h>
#include <dirent.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/stat.h>
#include "lib.h"
#include "parser.h"
#include "policy_cache.h"
#define le16_to_cpu(x) ((uint16_t)(le16toh (*(uint16_t *) x)))
const char header_string[] = "\004\010\000version\000\002";
#define HEADER_STRING_SIZE 12
#define VERSION_STRING_SIZE 4
bool valid_cached_file_version(const char *cachename)
{
char buffer[HEADER_STRING_SIZE + VERSION_STRING_SIZE];
autofclose FILE *f;
if (!(f = fopen(cachename, "r"))) {
PERROR("Error: Could not read cache file '%s', skipping...\n", cachename);
return false;
}
size_t res = fread(buffer, 1, HEADER_STRING_SIZE + VERSION_STRING_SIZE, f);
if (res < HEADER_STRING_SIZE + VERSION_STRING_SIZE) {
if (debug_cache)
pwarn("%s: cache file '%s' invalid size\n", progname, cachename);
return false;
}
/* 12 byte header that is always the same and then 4 byte version # */
if (memcmp(buffer, header_string, HEADER_STRING_SIZE) != 0) {
if (debug_cache)
pwarn("%s: cache file '%s' has wrong header\n", progname, cachename);
return false;
}
uint32_t version = cpu_to_le32(ENCODE_VERSION(force_complain,
policy_version,
parser_abi_version,
kernel_abi_version));
if (memcmp(buffer + HEADER_STRING_SIZE, &version, VERSION_STRING_SIZE) != 0) {
if (debug_cache)
pwarn("%s: cache file '%s' has wrong version\n", progname, cachename);
return false;
}
return true;
}
void set_cache_tstamp(struct timespec t)
{
mru_skip_cache = 0;
cache_tstamp = t;
}
void update_mru_tstamp(FILE *file, const char *name)
{
struct stat stat_file;
if (fstat(fileno(file), &stat_file))
return;
if (tstamp_cmp(mru_policy_tstamp, stat_file.st_mtim) < 0)
/* keep track of the most recent policy tstamp */
mru_policy_tstamp = stat_file.st_mtim;
if (tstamp_is_null(cache_tstamp))
return;
if (tstamp_cmp(stat_file.st_mtim, cache_tstamp) > 0) {
if (debug_cache)
pwarn("%s: file '%s' is newer than cache file\n", progname, name);
mru_skip_cache = 1;
}
}
char *cache_filename(aa_policy_cache *pc, int dir, const char *basename)
{
char *cachename;
autofree char *path;
path = aa_policy_cache_dir_path(pc, dir);
if (!path || asprintf(&cachename, "%s/%s", path, basename) < 0) {
PERROR("Memory allocation error.");
return NULL;
}
return cachename;
}
void valid_read_cache(const char *cachename)
{
struct stat stat_bin;
/* Load a binary cache if it exists and is newest */
if (!skip_read_cache) {
if (stat(cachename, &stat_bin) == 0 &&
stat_bin.st_size > 0) {
if (valid_cached_file_version(cachename))
set_cache_tstamp(stat_bin.st_mtim);
else if (!cond_clear_cache)
write_cache = 0;
} else {
if (!cond_clear_cache)
write_cache = 0;
if (debug_cache)
pwarn("%s: Invalid or missing cache file '%s' (%s)\n", progname, cachename, strerror(errno));
}
}
}
int cache_hit(const char *cachename)
{
if (!mru_skip_cache) {
if (show_cache)
PERROR("Cache hit: %s\n", cachename);
return true;
}
return false;
}
int setup_cache_tmp(const char **cachetmpname, const char *cachename)
{
char *tmpname;
int cache_fd = -1;
*cachetmpname = NULL;
if (write_cache) {
/* Otherwise, set up to save a cached copy */
if (asprintf(&tmpname, "%s-XXXXXX", cachename) < 0) {
perror("asprintf");
return -1;
}
if ((cache_fd = mkstemp(tmpname)) < 0) {
perror("mkstemp");
return -1;
}
*cachetmpname = tmpname;
}
return cache_fd;
}
void install_cache(const char *cachetmpname, const char *cachename)
{
/* Only install the generate cache file if it parsed correctly
and did not have write/close errors */
if (cachetmpname) {
struct timespec times[2];
/* set the mtime of the cache file to the most newest mtime
* of policy files used to generate it
*/
times[0].tv_sec = 0;
times[0].tv_nsec = UTIME_OMIT;
times[1] = mru_policy_tstamp;
if (utimensat(AT_FDCWD, cachetmpname, times, 0) < 0) {
PERROR("%s: Failed to set the mtime of cache file '%s': %m\n",
progname, cachename);
unlink(cachetmpname);
return;
}
if (rename(cachetmpname, cachename) < 0) {
pwarn("Warning failed to write cache: %s\n", cachename);
unlink(cachetmpname);
}
else if (show_cache) {
PERROR("Wrote cache: %s\n", cachename);
}
}
}
|
