RepoMirrors/netlink
1
0
Fork 0
mirror of https://github.com/vishvananda/netlink synced 2025-02-21 06:57:41 +00:00
Code Issues Packages Projects Releases Wiki Activity

Eliminate cgo from netlink.

Browse Source 
Signed-off-by: Christopher Koch <chrisko@google.com>
This commit is contained in:
Christopher Koch 2017-12-14 16:18:32 -08:00 committed by Alessandro Boch
parent 54ad9e3a4c
commit d4235bfaae
1 changed files with 37 additions and 46 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

83
bpf_linux.go
View File

@ -1,49 +1,12 @@
package netlink
/*
#include <asm/types.h>
#include <asm/unistd.h>
#include <errno.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
import (
"unsafe"
static int load_simple_bpf(int prog_type, int ret) {
#ifdef __NR_bpf
// { return ret; }
__u64 __attribute__((aligned(8))) insns[] = {
0x00000000000000b7ull | ((__u64)ret<<32),
0x0000000000000095ull,
};
__u8 __attribute__((aligned(8))) license[] = "ASL2";
// Copied from a header file since libc is notoriously slow to update.
// The call will succeed or fail and that will be our indication on
// whether or not it is supported.
struct {
__u32 prog_type;
__u32 insn_cnt;
__u64 insns;
__u64 license;
__u32 log_level;
__u32 log_size;
__u64 log_buf;
__u32 kern_version;
} __attribute__((aligned(8))) attr = {
.prog_type = prog_type,
.insn_cnt = 2,
.insns = (uintptr_t)&insns,
.license = (uintptr_t)&license,
};
return syscall(__NR_bpf, 5, &attr, sizeof(attr));
#else
errno = EINVAL;
return -1;
#endif
}
*/
import "C"
"golang.org/x/sys/unix"
)
type BpfProgType C.int
type BpfProgType uint32
const (
BPF_PROG_TYPE_UNSPEC BpfProgType = iota
@ -55,8 +18,36 @@ const (
BPF_PROG_TYPE_XDP
)
// loadSimpleBpf loads a trivial bpf program for testing purposes
func loadSimpleBpf(progType BpfProgType, ret int) (int, error) {
fd, err := C.load_simple_bpf(C.int(progType), C.int(ret))
return int(fd), err
type BPFAttr struct {
ProgType uint32
InsnCnt uint32
Insns uintptr
License uintptr
LogLevel uint32
LogSize uint32
LogBuf uintptr
KernVersion uint32
}
// loadSimpleBpf loads a trivial bpf program for testing purposes.
func loadSimpleBpf(progType BpfProgType, ret uint32) (int, error) {
insns := []uint64{
0x00000000000000b7 | (uint64(ret) << 32),
0x0000000000000095,
}
license := []byte{'A', 'S', 'L', '2', '\x00'}
attr := BPFAttr{
ProgType: uint32(progType),
InsnCnt: uint32(len(insns)),
Insns: uintptr(unsafe.Pointer(&insns)),
License: uintptr(unsafe.Pointer(&license[0])),
}
fd, _, errno := unix.Syscall(unix.SYS_BPF,
5, /* bpf cmd */
uintptr(unsafe.Pointer(&attr)),
unsafe.Sizeof(attr))
if errno != 0 {
return 0, errno
}
return int(fd), nil
}