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
|
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <inttypes.h>
#include <selinux/selinux.h>
#include <selinux/label.h>
#include "private/android_filesystem_config.h"
// This program takes a list of files and directories (indicated by a
// trailing slash) on the stdin, and prints to stdout each input
// filename along with its desired uid, gid, and mode (in octal).
// The leading slash should be stripped from the input.
//
// After the first 4 columns, optional key=value pairs are emitted
// for each file. Currently, the following keys are supported:
// * -S: selabel=[selinux_label]
// * -C: capabilities=[hex capabilities value]
//
// Example input:
//
// system/etc/dbus.conf
// data/app/
//
// Output:
//
// system/etc/dbus.conf 1002 1002 440
// data/app 1000 1000 771
//
// or if, for example, -S is used:
//
// system/etc/dbus.conf 1002 1002 440 selabel=u:object_r:system_file:s0
// data/app 1000 1000 771 selabel=u:object_r:apk_data_file:s0
//
// Note that the output will omit the trailing slash from
// directories.
static struct selabel_handle* get_sehnd(const char* context_file) {
struct selinux_opt seopts[] = { { SELABEL_OPT_PATH, context_file } };
struct selabel_handle* sehnd = selabel_open(SELABEL_CTX_FILE, seopts, 1);
if (!sehnd) {
perror("error running selabel_open");
exit(EXIT_FAILURE);
}
return sehnd;
}
static void usage() {
fprintf(stderr, "Usage: fs_config [-D product_out_path] [-S context_file] [-C]\n");
}
int main(int argc, char** argv) {
char buffer[1024];
const char* context_file = NULL;
const char* product_out_path = NULL;
struct selabel_handle* sehnd = NULL;
int print_capabilities = 0;
int opt;
while((opt = getopt(argc, argv, "CS:D:")) != -1) {
switch(opt) {
case 'C':
print_capabilities = 1;
break;
case 'S':
context_file = optarg;
break;
case 'D':
product_out_path = optarg;
break;
default:
usage();
exit(EXIT_FAILURE);
}
}
if (context_file != NULL) {
sehnd = get_sehnd(context_file);
}
while (fgets(buffer, 1023, stdin) != NULL) {
int is_dir = 0;
int i;
for (i = 0; i < 1024 && buffer[i]; ++i) {
switch (buffer[i]) {
case '\n':
buffer[i-is_dir] = '\0';
if (i == 0) {
is_dir = 1; // empty line is considered as root directory
}
i = 1025;
break;
case '/':
is_dir = 1;
break;
default:
is_dir = 0;
break;
}
}
unsigned uid = 0, gid = 0, mode = 0;
uint64_t capabilities;
fs_config(buffer, is_dir, product_out_path, &uid, &gid, &mode, &capabilities);
printf("%s %d %d %o", buffer, uid, gid, mode);
if (sehnd != NULL) {
size_t buffer_strlen = strnlen(buffer, sizeof(buffer));
if (buffer_strlen >= sizeof(buffer)) {
fprintf(stderr, "non null terminated buffer, aborting\n");
exit(EXIT_FAILURE);
}
size_t full_name_size = buffer_strlen + 2;
char* full_name = (char*) malloc(full_name_size);
if (full_name == NULL) {
perror("malloc");
exit(EXIT_FAILURE);
}
full_name[0] = '/';
strncpy(full_name + 1, buffer, full_name_size - 1);
full_name[full_name_size - 1] = '\0';
char* secontext;
if (selabel_lookup(sehnd, &secontext, full_name, ( mode | (is_dir ? S_IFDIR : S_IFREG)))) {
secontext = strdup("u:object_r:unlabeled:s0");
}
printf(" selabel=%s", secontext);
free(full_name);
freecon(secontext);
}
if (print_capabilities) {
printf(" capabilities=0x%" PRIx64, capabilities);
}
printf("\n");
}
return 0;
}
|
