seccomp_export_bpf(3) libseccomp Documentation seccomp_export_bpf(3)NAME
seccomp_export_bpf, seccomp_export_pfc - Export the seccomp filter
SYNOPSIS
#include <seccomp.h>
typedef void * scmp_filter_ctx;
int seccomp_export_bpf(const scmp_filter_ctx ctx, int fd);
int seccomp_export_pfc(const scmp_filter_ctx ctx, int fd);
Link with -lseccomp.
DESCRIPTION
The seccomp_export_bpf() and seccomp_export_pfc() functions generate
and output the current seccomp filter in either BPF (Berkley Packet
Filter) or PFC (Pseudo Filter Code). The output of sec‐
comp_export_bpf() is suitable for loading into the kernel, while the
output of seccomp_export_pfc() is human readable and is intended pri‐
marily as a debugging tool for developers using libseccomp. Both func‐
tions write the filter to the fd file descriptor.
The filter context ctx is the value returned by the call to sec‐
comp_init(3).
While the two output formats are guaranteed to be functionally equiva‐
lent for the given seccomp filter configuration, the filter instruc‐
tions, and their ordering, are not guaranteed to be the same in both
the BPF and PFC formats.
RETURN VALUE
Returns zero on success, negative errno values on failure.
EXAMPLES
#include <seccomp.h>
int main(int argc, char *argv[])
{
int rc = -1;
scmp_filter_ctx ctx;
int filter_fd;
ctx = seccomp_init(SCMP_ACT_KILL);
if (ctx == NULL)
goto out;
/* ... */
filter_fd = open("/tmp/seccomp_filter.bpf", O_WRONLY);
if (filter_fd == -1) {
rc = -errno;
goto out;
}
rc = seccomp_export_bpf(ctx, filter_fd);
if (rc < 0) {
close(filter_fd);
goto out;
}
close(filter_fd);
/* ... */
out:
seccomp_release(ctx);
return -rc;
}
NOTES
While the seccomp filter can be generated independent of the kernel,
kernel support is required to load and enforce the seccomp filter gen‐
erated by libseccomp.
The libseccomp project site, with more information and the source code
repository, can be found at http://libseccomp.sf.net. This library is
currently under development, please report any bugs at the project site
or directly to the author.
AUTHOR
Paul Moore <paul@paul-moore.com>
SEE ALSOseccomp_init(3), seccomp_release(3)paul@paul-moore.com 25 July 2012 seccomp_export_bpf(3)
