NAME

       seccomp_arch_add,  seccomp_arch_remove,  seccomp_arch_exist,  seccomp_arch_native - Manage seccomp filter
       architectures

SYNOPSIS

       #include <seccomp.h>

       typedef void * scmp_filter_ctx;

       #define SCMP_ARCH_NATIVE
       #define SCMP_ARCH_X86
       #define SCMP_ARCH_X86_64

       uint32_t seccomp_arch_native();
       int seccomp_arch_exist(const scmp_filter_ctx ctx, uint32_t arch_token);
       int seccomp_arch_add(scmp_filter_ctx ctx, uint32_t arch_token);
       int seccomp_arch_remove(scmp_filter_ctx ctx, uint32_t arch_token);

       Link with -lseccomp.

DESCRIPTION

       The seccomp_arch_exist() function tests to see if a given architecture has  been  added  to  the  seccomp
       filter  in  ctx  ,  where  the seccomp_arch_add() and seccomp_arch_remove() add and remove, respectively,
       architectures from the seccomp filter.   In  all  three  functions,  the  architecture  values  given  in
       arch_token  should  be  the  SCMP_ARCH_*  defined  constants;  with  the SCMP_ARCH_NATIVE constant always
       referring to the native compiled architecture.  The seccomp_arch_native() function returns  the  system's
       architecture such that it will match one of the SCMP_ARCH_* constants.

       When  a  seccomp  filter  is  initialized  with  the  call  to seccomp_init(3) the native architecture is
       automatically added to the filter.  If you want to remove the native architecture from  the  filter,  you
       first  need  to  add  another  architecture  to  the filter as a seccomp filter must contain at least one
       architecture at all times.  After you have added a second architecture to the  seccomp  filter,  you  can
       remove the native architecture.

       When  adding  a  new  architecture to an existing filter, the existing rules will not be added to the new
       architecture.  However, rules added after adding the new  architecture  will  be  added  to  all  of  the
       architectures in the filter.

RETURN VALUE

       The  seccomp_arch_add() and seccomp_arch_remove() functions return zero on success, negative errno values
       on failure.  The seccomp_arch_exist() function returns zero if the architecture  exists,  -EEXIST  if  it
       does not, and other 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_KILL);
            if (ctx == NULL)
                 goto out;

            if (seccomp_arch_exist(ctx, SCMP_ARCH_X86) == -EEXIST) {
                 rc = seccomp_arch_add(ctx, SCMP_ARCH_X86);
                 if (rc != 0)
                      goto out_all;
                 rc = seccomp_arch_remove(ctx, SCMP_ARCH_NATIVE);
                 if (rc != 0)
                      goto out_all;
            }

            /* ... */

       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 generated 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 ALSO

       seccomp_init(3), seccomp_reset(3), seccom_merge(3)