seccomp_attr_set(3) libseccomp Documentation seccomp_attr_set(3)NAME
seccomp_attr_set, seccomp_attr_get - Manage the seccomp filter
attributes
SYNOPSIS
#include <seccomp.h>
typedef void * scmp_filter_ctx;
enum scmp_filter_attr;
int seccomp_attr_set(scmp_filter_ctx ctx,
enum scmp_filter_attr attr, uint32_t value);
int seccomp_attr_get(scmp_filter_ctx ctx,
enum scmp_filter_attr attr, uint32_t *value);
Link with -lseccomp.
DESCRIPTION
The seccomp_attr_set() function sets the different seccomp filter
attributes while the seccomp_attr_get() function fetches the filter
attributes. The seccomp filter attributes are tunable values that
affect how the library behaves when generating and loading the seccomp
filter into the kernel. The attributes are reset to their default val‐
ues whenever the filter is initialized or reset via seccomp_fil‐
ter_init(3) or seccomp_filter_reset(3).
The filter context ctx is the value returned by the call to sec‐
comp_init(3).
Valid attr values are as follows:
SCMP_FLTATR_ACT_DEFAULT
The default filter action as specified in the call to sec‐
comp_filter_init(3) or seccomp_filter_reset(3). This attribute
is read-only.
SCMP_FLTATR_ACT_BADARCH
The filter action taken when the loaded filter does not match
the architecture of the executing application. Defaults to the
SCMP_ACT_KILL action.
SCMP_FLTATR_CTL_NNP
A flag to specify if the NO_NEW_PRIVS functionality should be
enabled before loading the seccomp filter into the kernel. If
set to off ( value == 0) then loading the seccomp filter into
the kernel will fail if CAP_SYS_ADMIN is not set. Defaults to
on ( value == 1).
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;
ctx = seccomp_init(SCMP_ACT_ALLOW);
if (ctx == NULL)
goto out;
/* ... */
rc = seccomp_attr_set(ctx, SCMP_FLTATR_ACT_BADARCH, SCMP_ACT_TRAP);
if (rc < 0)
goto out;
/* ... */
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_reset(3), seccomp_load(3)paul@paul-moore.com 25 July 2012 seccomp_attr_set(3)
