diff options
Diffstat (limited to 'vendor/github.com/cilium/ebpf/internal/sys/syscall.go')
-rw-r--r-- | vendor/github.com/cilium/ebpf/internal/sys/syscall.go | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/vendor/github.com/cilium/ebpf/internal/sys/syscall.go b/vendor/github.com/cilium/ebpf/internal/sys/syscall.go new file mode 100644 index 000000000..2a5935dc9 --- /dev/null +++ b/vendor/github.com/cilium/ebpf/internal/sys/syscall.go @@ -0,0 +1,126 @@ +package sys + +import ( + "runtime" + "syscall" + "unsafe" + + "github.com/cilium/ebpf/internal/unix" +) + +// BPF wraps SYS_BPF. +// +// Any pointers contained in attr must use the Pointer type from this package. +func BPF(cmd Cmd, attr unsafe.Pointer, size uintptr) (uintptr, error) { + for { + r1, _, errNo := unix.Syscall(unix.SYS_BPF, uintptr(cmd), uintptr(attr), size) + runtime.KeepAlive(attr) + + // As of ~4.20 the verifier can be interrupted by a signal, + // and returns EAGAIN in that case. + if errNo == unix.EAGAIN && cmd == BPF_PROG_LOAD { + continue + } + + var err error + if errNo != 0 { + err = wrappedErrno{errNo} + } + + return r1, err + } +} + +// Info is implemented by all structs that can be passed to the ObjInfo syscall. +// +// MapInfo +// ProgInfo +// LinkInfo +// BtfInfo +type Info interface { + info() (unsafe.Pointer, uint32) +} + +var _ Info = (*MapInfo)(nil) + +func (i *MapInfo) info() (unsafe.Pointer, uint32) { + return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i)) +} + +var _ Info = (*ProgInfo)(nil) + +func (i *ProgInfo) info() (unsafe.Pointer, uint32) { + return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i)) +} + +var _ Info = (*LinkInfo)(nil) + +func (i *LinkInfo) info() (unsafe.Pointer, uint32) { + return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i)) +} + +var _ Info = (*BtfInfo)(nil) + +func (i *BtfInfo) info() (unsafe.Pointer, uint32) { + return unsafe.Pointer(i), uint32(unsafe.Sizeof(*i)) +} + +// ObjInfo retrieves information about a BPF Fd. +// +// info may be one of MapInfo, ProgInfo, LinkInfo and BtfInfo. +func ObjInfo(fd *FD, info Info) error { + ptr, len := info.info() + err := ObjGetInfoByFd(&ObjGetInfoByFdAttr{ + BpfFd: fd.Uint(), + InfoLen: len, + Info: NewPointer(ptr), + }) + runtime.KeepAlive(fd) + return err +} + +// BPFObjName is a null-terminated string made up of +// 'A-Za-z0-9_' characters. +type ObjName [unix.BPF_OBJ_NAME_LEN]byte + +// NewObjName truncates the result if it is too long. +func NewObjName(name string) ObjName { + var result ObjName + copy(result[:unix.BPF_OBJ_NAME_LEN-1], name) + return result +} + +// LinkID uniquely identifies a bpf_link. +type LinkID uint32 + +// BTFID uniquely identifies a BTF blob loaded into the kernel. +type BTFID uint32 + +// wrappedErrno wraps syscall.Errno to prevent direct comparisons with +// syscall.E* or unix.E* constants. +// +// You should never export an error of this type. +type wrappedErrno struct { + syscall.Errno +} + +func (we wrappedErrno) Unwrap() error { + return we.Errno +} + +type syscallError struct { + error + errno syscall.Errno +} + +func Error(err error, errno syscall.Errno) error { + return &syscallError{err, errno} +} + +func (se *syscallError) Is(target error) bool { + return target == se.error +} + +func (se *syscallError) Unwrap() error { + return se.errno +} |