приоритет системным вызовам в фильтре seccomp (Prioritize syscalls in the seccomp filter)
Имя (Name)
seccomp_syscall_priority - Prioritize syscalls in the seccomp
filter
Синопсис (Synopsis)
#include <seccomp.h>
typedef void * scmp_filter_ctx;
int SCMP_SYS(
syscall_name);
int seccomp_syscall_priority(scmp_filter_ctx
ctx,
int
syscall, uint8_t
priority);
Link with -lseccomp.
Описание (Description)
The seccomp_syscall_priority
() function provides a priority hint
to the seccomp filter generator in libseccomp such that higher
priority syscalls are placed earlier in the seccomp filter code
so that they incur less overhead at the expense of lower priority
syscalls. A syscall's priority can be set regardless of if any
rules currently exist for that syscall; the library will remember
the priority and it will be assigned to the syscall if and when a
rule for that syscall is created.
While it is possible to specify the syscall value directly using
the standard __NR_syscall
values, in order to ensure proper
operation across multiple architectures it is highly recommended
to use the SCMP_SYS
() macro instead. See the EXAMPLES section
below.
The priority parameter takes an 8-bit value ranging from 0 - 255;
a higher value represents a higher priority.
The filter context ctx is the value returned by the call to
seccomp_init
().
Возвращаемое значение (Return value)
The SCMP_SYS
() macro returns a value suitable for use as the
syscall value in seccomp_syscall_priority
().
The seccomp_syscall_priority
() function returns zero on success
or one of the following error codes on failure:
-EDOM
Architecture specific failure.
-EFAULT
Internal libseccomp failure.
-EINVAL
Invalid input, either the context or architecture token is
invalid.
-ENOMEM
The library was unable to allocate enough memory.
Примеры (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;
/* ... */
rc = seccomp_syscall_priority(ctx, SCMP_SYS(read), 200);
if (rc < 0)
goto out;
/* ... */
out:
seccomp_release(ctx);
return -rc;
}
Примечание (Note)
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
https://github.com/seccomp/libseccomp. This tool, as well as the
libseccomp library, is currently under development, please report
any bugs at the project site or directly to the author.