projects / linux-seccomp.git / blame
| Commit | Line | Data |
|---|---|---|
| 8befd5cc MG |
1 | .TH "seccomp_export_bpf" 3 "25 July 2012" "paul@paul-moore.com" "libseccomp Documentation" |
| 2 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 3 | .SH NAME | |
| 4 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 5 | seccomp_export_bpf, seccomp_export_pfc \- Export the seccomp filter | |
| 6 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 7 | .SH SYNOPSIS | |
| 8 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 9 | .nf | |
| 10 | .B #include <seccomp.h> | |
| 11 | .sp | |
| 12 | .B typedef void * scmp_filter_ctx; | |
| 13 | .sp | |
| 14 | .BI "int seccomp_export_bpf(const scmp_filter_ctx " ctx ", int " fd ");" | |
| 15 | .BI "int seccomp_export_pfc(const scmp_filter_ctx " ctx ", int " fd ");" | |
| 16 | .sp | |
| 17 | Link with \fI\-lseccomp\fP. | |
| 18 | .fi | |
| 19 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 20 | .SH DESCRIPTION | |
| 21 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 22 | .P | |
| 23 | The | |
| 24 | .BR seccomp_export_bpf () | |
| 25 | and | |
| 26 | .BR seccomp_export_pfc () | |
| 27 | functions generate and output the current seccomp filter in either BPF (Berkley | |
| 28 | Packet Filter) or PFC (Pseudo Filter Code). The output of | |
| 29 | .BR seccomp_export_bpf () | |
| 30 | is suitable for loading into the kernel, while the output of | |
| 31 | .BR seccomp_export_pfc () | |
| 32 | is human readable and is intended primarily as a debugging tool for developers | |
| 33 | using libseccomp. Both functions write the filter to the | |
| 34 | .I fd | |
| 35 | file descriptor. | |
| 36 | .P | |
| 37 | The filter context | |
| 38 | .I ctx | |
| 39 | is the value returned by the call to | |
| 40 | .BR seccomp_init (3). | |
| 41 | .P | |
| 42 | While the two output formats are guaranteed to be functionally equivalent for | |
| 43 | the given seccomp filter configuration, the filter instructions, and their | |
| 44 | ordering, are not guaranteed to be the same in both the BPF and PFC formats. | |
| 45 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 46 | .SH RETURN VALUE | |
| 47 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 48 | Returns zero on success, negative errno values on failure. | |
| 49 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 50 | .SH EXAMPLES | |
| 51 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 52 | .nf | |
| 53 | #include <seccomp.h> | |
| 54 | ||
| 55 | int main(int argc, char *argv[]) | |
| 56 | { | |
| 57 | int rc = \-1; | |
| 58 | scmp_filter_ctx ctx; | |
| 59 | int filter_fd; | |
| 60 | ||
| 61 | ctx = seccomp_init(SCMP_ACT_KILL); | |
| 62 | if (ctx == NULL) | |
| 63 | goto out; | |
| 64 | ||
| 65 | /* ... */ | |
| 66 | ||
| 67 | filter_fd = open("/tmp/seccomp_filter.bpf", O_WRONLY); | |
| 68 | if (filter_fd == \-1) { | |
| 69 | rc = \-errno; | |
| 70 | goto out; | |
| 71 | } | |
| 72 | ||
| 73 | rc = seccomp_export_bpf(ctx, filter_fd); | |
| 74 | if (rc < 0) { | |
| 75 | close(filter_fd); | |
| 76 | goto out; | |
| 77 | } | |
| 78 | close(filter_fd); | |
| 79 | ||
| 80 | /* ... */ | |
| 81 | ||
| 82 | out: | |
| 83 | seccomp_release(ctx); | |
| 84 | return \-rc; | |
| 85 | } | |
| 86 | .fi | |
| 87 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 88 | .SH NOTES | |
| 89 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 90 | .P | |
| 91 | While the seccomp filter can be generated independent of the kernel, kernel | |
| 92 | support is required to load and enforce the seccomp filter generated by | |
| 93 | libseccomp. | |
| 94 | .P | |
| 95 | The libseccomp project site, with more information and the source code | |
| 96 | repository, can be found at https://github.com/seccomp/libseccomp. This tool, | |
| 97 | as well as the libseccomp library, is currently under development, please | |
| 98 | report any bugs at the project site or directly to the author. | |
| 99 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 100 | .SH AUTHOR | |
| 101 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 102 | Paul Moore <paul@paul-moore.com> | |
| 103 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 104 | .SH SEE ALSO | |
| 105 | .\" ////////////////////////////////////////////////////////////////////////// | |
| 106 | .BR seccomp_init (3), | |
| 107 | .BR seccomp_release (3) | |
| 108 |