diff options
Diffstat (limited to 'src/fsec-optimize/main.c')
-rw-r--r-- | src/fsec-optimize/main.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/src/fsec-optimize/main.c b/src/fsec-optimize/main.c new file mode 100644 index 000000000..2c11b91ef --- /dev/null +++ b/src/fsec-optimize/main.c | |||
@@ -0,0 +1,94 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2014-2017 Firejail Authors | ||
3 | * | ||
4 | * This file is part of firejail project | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License as published by | ||
8 | * the Free Software Foundation; either version 2 of the License, or | ||
9 | * (at your option) any later version. | ||
10 | * | ||
11 | * This program is distributed in the hope that it will be useful, | ||
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
14 | * GNU General Public License for more details. | ||
15 | * | ||
16 | * You should have received a copy of the GNU General Public License along | ||
17 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
18 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | ||
19 | */ | ||
20 | #include "fsec_optimize.h" | ||
21 | |||
22 | static void usage(void) { | ||
23 | printf("Usage:\n"); | ||
24 | printf("\tfsec-optimize file - optimize seccomp filter\n"); | ||
25 | } | ||
26 | |||
27 | int main(int argc, char **argv) { | ||
28 | #if 0 | ||
29 | { | ||
30 | //system("cat /proc/self/status"); | ||
31 | int i; | ||
32 | for (i = 0; i < argc; i++) | ||
33 | printf("*%s* ", argv[i]); | ||
34 | printf("\n"); | ||
35 | } | ||
36 | #endif | ||
37 | if (argc != 2) { | ||
38 | usage(); | ||
39 | return 1; | ||
40 | } | ||
41 | |||
42 | if (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0) { | ||
43 | usage(); | ||
44 | return 0; | ||
45 | } | ||
46 | |||
47 | char *fname = argv[1]; | ||
48 | |||
49 | // open input file | ||
50 | int fd = open(fname, O_RDONLY); | ||
51 | if (fd == -1) | ||
52 | goto errexit; | ||
53 | |||
54 | // calculate the number of entries | ||
55 | int size = lseek(fd, 0, SEEK_END); | ||
56 | if (size == -1) // todo: check maximum size of seccomp filter (4KB?) | ||
57 | goto errexit; | ||
58 | unsigned short entries = (unsigned short) size / (unsigned short) sizeof(struct sock_filter); | ||
59 | |||
60 | // read filter | ||
61 | struct sock_filter *filter = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); | ||
62 | if (filter == MAP_FAILED) | ||
63 | goto errexit; | ||
64 | close(fd); | ||
65 | |||
66 | // duplicate the filter memory and unmap the file | ||
67 | struct sock_filter *outfilter = duplicate(filter, entries); | ||
68 | if (munmap(filter, size) == -1) | ||
69 | perror("Error un-mmapping the file"); | ||
70 | |||
71 | // optimize filter | ||
72 | entries = optimize(outfilter, entries); | ||
73 | |||
74 | // write the new file and free memory | ||
75 | fd = open(argv[1], O_WRONLY | O_TRUNC | O_CREAT, 0755); | ||
76 | if (fd == -1) { | ||
77 | fprintf(stderr, "Error: cannot open output file\n"); | ||
78 | return 1; | ||
79 | } | ||
80 | size = write(fd, outfilter, entries * sizeof(struct sock_filter)); | ||
81 | if (size != entries * sizeof(struct sock_filter)) { | ||
82 | fprintf(stderr, "Error: cannot write output file\n"); | ||
83 | return 1; | ||
84 | } | ||
85 | close(fd); | ||
86 | free(outfilter); | ||
87 | |||
88 | return 0; | ||
89 | errexit: | ||
90 | close(fd); | ||
91 | fprintf(stderr, "Error: cannot read %s\n", fname); | ||
92 | exit(1); | ||
93 | |||
94 | } | ||