mirror of
https://github.com/superseriousbusiness/gotosocial.git
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57dc742c76
Bumps [github.com/KimMachineGun/automemlimit](https://github.com/KimMachineGun/automemlimit) from 0.2.4 to 0.2.5. - [Release notes](https://github.com/KimMachineGun/automemlimit/releases) - [Commits](https://github.com/KimMachineGun/automemlimit/compare/v0.2.4...v0.2.5) --- updated-dependencies: - dependency-name: github.com/KimMachineGun/automemlimit dependency-type: direct:production update-type: version-update:semver-patch ... Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
1425 lines
37 KiB
Go
1425 lines
37 KiB
Go
package ebpf
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import (
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"bytes"
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"errors"
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"fmt"
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"io"
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"math/rand"
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"path/filepath"
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"reflect"
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"time"
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"unsafe"
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"github.com/cilium/ebpf/btf"
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"github.com/cilium/ebpf/internal"
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"github.com/cilium/ebpf/internal/sys"
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"github.com/cilium/ebpf/internal/unix"
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)
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// Errors returned by Map and MapIterator methods.
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var (
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ErrKeyNotExist = errors.New("key does not exist")
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ErrKeyExist = errors.New("key already exists")
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ErrIterationAborted = errors.New("iteration aborted")
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ErrMapIncompatible = errors.New("map spec is incompatible with existing map")
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errMapNoBTFValue = errors.New("map spec does not contain a BTF Value")
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)
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// MapOptions control loading a map into the kernel.
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type MapOptions struct {
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// The base path to pin maps in if requested via PinByName.
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// Existing maps will be re-used if they are compatible, otherwise an
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// error is returned.
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PinPath string
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LoadPinOptions LoadPinOptions
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}
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// MapID represents the unique ID of an eBPF map
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type MapID uint32
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// MapSpec defines a Map.
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type MapSpec struct {
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// Name is passed to the kernel as a debug aid. Must only contain
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// alpha numeric and '_' characters.
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Name string
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Type MapType
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KeySize uint32
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ValueSize uint32
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MaxEntries uint32
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// Flags is passed to the kernel and specifies additional map
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// creation attributes.
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Flags uint32
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// Automatically pin and load a map from MapOptions.PinPath.
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// Generates an error if an existing pinned map is incompatible with the MapSpec.
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Pinning PinType
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// Specify numa node during map creation
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// (effective only if unix.BPF_F_NUMA_NODE flag is set,
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// which can be imported from golang.org/x/sys/unix)
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NumaNode uint32
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// The initial contents of the map. May be nil.
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Contents []MapKV
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// Whether to freeze a map after setting its initial contents.
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Freeze bool
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// InnerMap is used as a template for ArrayOfMaps and HashOfMaps
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InnerMap *MapSpec
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// Extra trailing bytes found in the ELF map definition when using structs
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// larger than libbpf's bpf_map_def. nil if no trailing bytes were present.
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// Must be nil or empty before instantiating the MapSpec into a Map.
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Extra *bytes.Reader
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// The key and value type of this map. May be nil.
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Key, Value btf.Type
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// The BTF associated with this map.
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BTF *btf.Spec
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}
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func (ms *MapSpec) String() string {
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return fmt.Sprintf("%s(keySize=%d, valueSize=%d, maxEntries=%d, flags=%d)", ms.Type, ms.KeySize, ms.ValueSize, ms.MaxEntries, ms.Flags)
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}
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// Copy returns a copy of the spec.
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//
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// MapSpec.Contents is a shallow copy.
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func (ms *MapSpec) Copy() *MapSpec {
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if ms == nil {
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return nil
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}
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cpy := *ms
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cpy.Contents = make([]MapKV, len(ms.Contents))
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copy(cpy.Contents, ms.Contents)
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cpy.InnerMap = ms.InnerMap.Copy()
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return &cpy
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}
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// hasBTF returns true if the MapSpec has a valid BTF spec and if its
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// map type supports associated BTF metadata in the kernel.
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func (ms *MapSpec) hasBTF() bool {
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return ms.BTF != nil && ms.Type.hasBTF()
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}
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func (ms *MapSpec) clampPerfEventArraySize() error {
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if ms.Type != PerfEventArray {
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return nil
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}
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n, err := internal.PossibleCPUs()
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if err != nil {
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return fmt.Errorf("perf event array: %w", err)
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}
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if n := uint32(n); ms.MaxEntries > n {
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ms.MaxEntries = n
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}
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return nil
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}
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// dataSection returns the contents and BTF Datasec descriptor of the spec.
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func (ms *MapSpec) dataSection() ([]byte, *btf.Datasec, error) {
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if ms.Value == nil {
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return nil, nil, errMapNoBTFValue
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}
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ds, ok := ms.Value.(*btf.Datasec)
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if !ok {
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return nil, nil, fmt.Errorf("map value BTF is a %T, not a *btf.Datasec", ms.Value)
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}
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if n := len(ms.Contents); n != 1 {
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return nil, nil, fmt.Errorf("expected one key, found %d", n)
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}
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kv := ms.Contents[0]
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value, ok := kv.Value.([]byte)
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if !ok {
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return nil, nil, fmt.Errorf("value at first map key is %T, not []byte", kv.Value)
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}
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return value, ds, nil
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}
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// MapKV is used to initialize the contents of a Map.
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type MapKV struct {
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Key interface{}
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Value interface{}
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}
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func (ms *MapSpec) checkCompatibility(m *Map) error {
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switch {
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case m.typ != ms.Type:
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return fmt.Errorf("expected type %v, got %v: %w", ms.Type, m.typ, ErrMapIncompatible)
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case m.keySize != ms.KeySize:
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return fmt.Errorf("expected key size %v, got %v: %w", ms.KeySize, m.keySize, ErrMapIncompatible)
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case m.valueSize != ms.ValueSize:
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return fmt.Errorf("expected value size %v, got %v: %w", ms.ValueSize, m.valueSize, ErrMapIncompatible)
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case !(ms.Type == PerfEventArray && ms.MaxEntries == 0) &&
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m.maxEntries != ms.MaxEntries:
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return fmt.Errorf("expected max entries %v, got %v: %w", ms.MaxEntries, m.maxEntries, ErrMapIncompatible)
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case m.flags != ms.Flags:
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return fmt.Errorf("expected flags %v, got %v: %w", ms.Flags, m.flags, ErrMapIncompatible)
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}
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return nil
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}
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// Map represents a Map file descriptor.
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//
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// It is not safe to close a map which is used by other goroutines.
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//
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// Methods which take interface{} arguments by default encode
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// them using binary.Read/Write in the machine's native endianness.
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//
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// Implement encoding.BinaryMarshaler or encoding.BinaryUnmarshaler
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// if you require custom encoding.
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type Map struct {
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name string
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fd *sys.FD
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typ MapType
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keySize uint32
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valueSize uint32
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maxEntries uint32
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flags uint32
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pinnedPath string
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// Per CPU maps return values larger than the size in the spec
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fullValueSize int
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}
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// NewMapFromFD creates a map from a raw fd.
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//
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// You should not use fd after calling this function.
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func NewMapFromFD(fd int) (*Map, error) {
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f, err := sys.NewFD(fd)
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if err != nil {
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return nil, err
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}
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return newMapFromFD(f)
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}
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func newMapFromFD(fd *sys.FD) (*Map, error) {
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info, err := newMapInfoFromFd(fd)
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if err != nil {
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fd.Close()
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return nil, fmt.Errorf("get map info: %w", err)
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}
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return newMap(fd, info.Name, info.Type, info.KeySize, info.ValueSize, info.MaxEntries, info.Flags)
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}
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// NewMap creates a new Map.
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//
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// It's equivalent to calling NewMapWithOptions with default options.
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func NewMap(spec *MapSpec) (*Map, error) {
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return NewMapWithOptions(spec, MapOptions{})
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}
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// NewMapWithOptions creates a new Map.
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//
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// Creating a map for the first time will perform feature detection
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// by creating small, temporary maps.
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//
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// The caller is responsible for ensuring the process' rlimit is set
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// sufficiently high for locking memory during map creation. This can be done
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// by calling rlimit.RemoveMemlock() prior to calling NewMapWithOptions.
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//
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// May return an error wrapping ErrMapIncompatible.
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func NewMapWithOptions(spec *MapSpec, opts MapOptions) (*Map, error) {
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handles := newHandleCache()
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defer handles.close()
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m, err := newMapWithOptions(spec, opts, handles)
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if err != nil {
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return nil, fmt.Errorf("creating map: %w", err)
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}
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if err := m.finalize(spec); err != nil {
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m.Close()
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return nil, fmt.Errorf("populating map: %w", err)
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}
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return m, nil
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}
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func newMapWithOptions(spec *MapSpec, opts MapOptions, handles *handleCache) (_ *Map, err error) {
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closeOnError := func(c io.Closer) {
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if err != nil {
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c.Close()
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}
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}
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switch spec.Pinning {
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case PinByName:
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if spec.Name == "" {
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return nil, fmt.Errorf("pin by name: missing Name")
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}
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if opts.PinPath == "" {
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return nil, fmt.Errorf("pin by name: missing MapOptions.PinPath")
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}
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path := filepath.Join(opts.PinPath, spec.Name)
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m, err := LoadPinnedMap(path, &opts.LoadPinOptions)
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if errors.Is(err, unix.ENOENT) {
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break
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}
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if err != nil {
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return nil, fmt.Errorf("load pinned map: %w", err)
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}
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defer closeOnError(m)
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if err := spec.checkCompatibility(m); err != nil {
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return nil, fmt.Errorf("use pinned map %s: %w", spec.Name, err)
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}
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return m, nil
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case PinNone:
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// Nothing to do here
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default:
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return nil, fmt.Errorf("pin type %d: %w", int(spec.Pinning), ErrNotSupported)
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}
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var innerFd *sys.FD
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if spec.Type == ArrayOfMaps || spec.Type == HashOfMaps {
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if spec.InnerMap == nil {
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return nil, fmt.Errorf("%s requires InnerMap", spec.Type)
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}
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if spec.InnerMap.Pinning != PinNone {
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return nil, errors.New("inner maps cannot be pinned")
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}
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template, err := spec.InnerMap.createMap(nil, opts, handles)
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if err != nil {
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return nil, fmt.Errorf("inner map: %w", err)
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}
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defer template.Close()
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// Intentionally skip populating and freezing (finalizing)
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// the inner map template since it will be removed shortly.
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innerFd = template.fd
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}
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m, err := spec.createMap(innerFd, opts, handles)
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if err != nil {
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return nil, err
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}
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defer closeOnError(m)
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if spec.Pinning == PinByName {
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path := filepath.Join(opts.PinPath, spec.Name)
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if err := m.Pin(path); err != nil {
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return nil, fmt.Errorf("pin map: %w", err)
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}
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}
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return m, nil
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}
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// createMap validates the spec's properties and creates the map in the kernel
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// using the given opts. It does not populate or freeze the map.
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func (spec *MapSpec) createMap(inner *sys.FD, opts MapOptions, handles *handleCache) (_ *Map, err error) {
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closeOnError := func(closer io.Closer) {
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if err != nil {
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closer.Close()
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}
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}
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spec = spec.Copy()
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// Kernels 4.13 through 5.4 used a struct bpf_map_def that contained
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// additional 'inner_map_idx' and later 'numa_node' fields.
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// In order to support loading these definitions, tolerate the presence of
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// extra bytes, but require them to be zeroes.
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if spec.Extra != nil {
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if _, err := io.Copy(internal.DiscardZeroes{}, spec.Extra); err != nil {
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return nil, errors.New("extra contains unhandled non-zero bytes, drain before creating map")
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}
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}
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switch spec.Type {
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case ArrayOfMaps, HashOfMaps:
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if err := haveNestedMaps(); err != nil {
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return nil, err
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}
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if spec.ValueSize != 0 && spec.ValueSize != 4 {
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return nil, errors.New("ValueSize must be zero or four for map of map")
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}
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spec.ValueSize = 4
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case PerfEventArray:
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if spec.KeySize != 0 && spec.KeySize != 4 {
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return nil, errors.New("KeySize must be zero or four for perf event array")
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}
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spec.KeySize = 4
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if spec.ValueSize != 0 && spec.ValueSize != 4 {
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return nil, errors.New("ValueSize must be zero or four for perf event array")
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}
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spec.ValueSize = 4
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if spec.MaxEntries == 0 {
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n, err := internal.PossibleCPUs()
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if err != nil {
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return nil, fmt.Errorf("perf event array: %w", err)
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}
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spec.MaxEntries = uint32(n)
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}
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}
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if spec.Flags&(unix.BPF_F_RDONLY_PROG|unix.BPF_F_WRONLY_PROG) > 0 || spec.Freeze {
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if err := haveMapMutabilityModifiers(); err != nil {
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return nil, fmt.Errorf("map create: %w", err)
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}
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}
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if spec.Flags&unix.BPF_F_MMAPABLE > 0 {
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if err := haveMmapableMaps(); err != nil {
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return nil, fmt.Errorf("map create: %w", err)
|
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}
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}
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if spec.Flags&unix.BPF_F_INNER_MAP > 0 {
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if err := haveInnerMaps(); err != nil {
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return nil, fmt.Errorf("map create: %w", err)
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}
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}
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if spec.Flags&unix.BPF_F_NO_PREALLOC > 0 {
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if err := haveNoPreallocMaps(); err != nil {
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return nil, fmt.Errorf("map create: %w", err)
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}
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}
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attr := sys.MapCreateAttr{
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MapType: sys.MapType(spec.Type),
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KeySize: spec.KeySize,
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ValueSize: spec.ValueSize,
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MaxEntries: spec.MaxEntries,
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MapFlags: spec.Flags,
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NumaNode: spec.NumaNode,
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}
|
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|
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if inner != nil {
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attr.InnerMapFd = inner.Uint()
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}
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|
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if haveObjName() == nil {
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attr.MapName = sys.NewObjName(spec.Name)
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}
|
|
|
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if spec.hasBTF() {
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handle, err := handles.btfHandle(spec.BTF)
|
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if err != nil && !errors.Is(err, btf.ErrNotSupported) {
|
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return nil, fmt.Errorf("load BTF: %w", err)
|
|
}
|
|
|
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if handle != nil {
|
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keyTypeID, err := spec.BTF.TypeID(spec.Key)
|
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if err != nil {
|
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return nil, err
|
|
}
|
|
|
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valueTypeID, err := spec.BTF.TypeID(spec.Value)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
attr.BtfFd = uint32(handle.FD())
|
|
attr.BtfKeyTypeId = uint32(keyTypeID)
|
|
attr.BtfValueTypeId = uint32(valueTypeID)
|
|
}
|
|
}
|
|
|
|
fd, err := sys.MapCreate(&attr)
|
|
if err != nil {
|
|
if errors.Is(err, unix.EPERM) {
|
|
return nil, fmt.Errorf("map create: %w (MEMLOCK may be too low, consider rlimit.RemoveMemlock)", err)
|
|
}
|
|
if !spec.hasBTF() {
|
|
return nil, fmt.Errorf("map create without BTF: %w", err)
|
|
}
|
|
if errors.Is(err, unix.EINVAL) && attr.MaxEntries == 0 {
|
|
return nil, fmt.Errorf("map create: %w (MaxEntries may be incorrectly set to zero)", err)
|
|
}
|
|
return nil, fmt.Errorf("map create: %w", err)
|
|
}
|
|
defer closeOnError(fd)
|
|
|
|
m, err := newMap(fd, spec.Name, spec.Type, spec.KeySize, spec.ValueSize, spec.MaxEntries, spec.Flags)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("map create: %w", err)
|
|
}
|
|
|
|
return m, nil
|
|
}
|
|
|
|
// newMap allocates and returns a new Map structure.
|
|
// Sets the fullValueSize on per-CPU maps.
|
|
func newMap(fd *sys.FD, name string, typ MapType, keySize, valueSize, maxEntries, flags uint32) (*Map, error) {
|
|
m := &Map{
|
|
name,
|
|
fd,
|
|
typ,
|
|
keySize,
|
|
valueSize,
|
|
maxEntries,
|
|
flags,
|
|
"",
|
|
int(valueSize),
|
|
}
|
|
|
|
if !typ.hasPerCPUValue() {
|
|
return m, nil
|
|
}
|
|
|
|
possibleCPUs, err := internal.PossibleCPUs()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
m.fullValueSize = internal.Align(int(valueSize), 8) * possibleCPUs
|
|
return m, nil
|
|
}
|
|
|
|
func (m *Map) String() string {
|
|
if m.name != "" {
|
|
return fmt.Sprintf("%s(%s)#%v", m.typ, m.name, m.fd)
|
|
}
|
|
return fmt.Sprintf("%s#%v", m.typ, m.fd)
|
|
}
|
|
|
|
// Type returns the underlying type of the map.
|
|
func (m *Map) Type() MapType {
|
|
return m.typ
|
|
}
|
|
|
|
// KeySize returns the size of the map key in bytes.
|
|
func (m *Map) KeySize() uint32 {
|
|
return m.keySize
|
|
}
|
|
|
|
// ValueSize returns the size of the map value in bytes.
|
|
func (m *Map) ValueSize() uint32 {
|
|
return m.valueSize
|
|
}
|
|
|
|
// MaxEntries returns the maximum number of elements the map can hold.
|
|
func (m *Map) MaxEntries() uint32 {
|
|
return m.maxEntries
|
|
}
|
|
|
|
// Flags returns the flags of the map.
|
|
func (m *Map) Flags() uint32 {
|
|
return m.flags
|
|
}
|
|
|
|
// Info returns metadata about the map.
|
|
func (m *Map) Info() (*MapInfo, error) {
|
|
return newMapInfoFromFd(m.fd)
|
|
}
|
|
|
|
// MapLookupFlags controls the behaviour of the map lookup calls.
|
|
type MapLookupFlags uint64
|
|
|
|
// LookupLock look up the value of a spin-locked map.
|
|
const LookupLock MapLookupFlags = 4
|
|
|
|
// Lookup retrieves a value from a Map.
|
|
//
|
|
// Calls Close() on valueOut if it is of type **Map or **Program,
|
|
// and *valueOut is not nil.
|
|
//
|
|
// Returns an error if the key doesn't exist, see ErrKeyNotExist.
|
|
func (m *Map) Lookup(key, valueOut interface{}) error {
|
|
valuePtr, valueBytes := makeBuffer(valueOut, m.fullValueSize)
|
|
if err := m.lookup(key, valuePtr, 0); err != nil {
|
|
return err
|
|
}
|
|
|
|
return m.unmarshalValue(valueOut, valueBytes)
|
|
}
|
|
|
|
// LookupWithFlags retrieves a value from a Map with flags.
|
|
//
|
|
// Passing LookupLock flag will look up the value of a spin-locked
|
|
// map without returning the lock. This must be specified if the
|
|
// elements contain a spinlock.
|
|
//
|
|
// Calls Close() on valueOut if it is of type **Map or **Program,
|
|
// and *valueOut is not nil.
|
|
//
|
|
// Returns an error if the key doesn't exist, see ErrKeyNotExist.
|
|
func (m *Map) LookupWithFlags(key, valueOut interface{}, flags MapLookupFlags) error {
|
|
valuePtr, valueBytes := makeBuffer(valueOut, m.fullValueSize)
|
|
if err := m.lookup(key, valuePtr, flags); err != nil {
|
|
return err
|
|
}
|
|
|
|
return m.unmarshalValue(valueOut, valueBytes)
|
|
}
|
|
|
|
// LookupAndDelete retrieves and deletes a value from a Map.
|
|
//
|
|
// Returns ErrKeyNotExist if the key doesn't exist.
|
|
func (m *Map) LookupAndDelete(key, valueOut interface{}) error {
|
|
return m.lookupAndDelete(key, valueOut, 0)
|
|
}
|
|
|
|
// LookupAndDeleteWithFlags retrieves and deletes a value from a Map.
|
|
//
|
|
// Passing LookupLock flag will look up and delete the value of a spin-locked
|
|
// map without returning the lock. This must be specified if the elements
|
|
// contain a spinlock.
|
|
//
|
|
// Returns ErrKeyNotExist if the key doesn't exist.
|
|
func (m *Map) LookupAndDeleteWithFlags(key, valueOut interface{}, flags MapLookupFlags) error {
|
|
return m.lookupAndDelete(key, valueOut, flags)
|
|
}
|
|
|
|
// LookupBytes gets a value from Map.
|
|
//
|
|
// Returns a nil value if a key doesn't exist.
|
|
func (m *Map) LookupBytes(key interface{}) ([]byte, error) {
|
|
valueBytes := make([]byte, m.fullValueSize)
|
|
valuePtr := sys.NewSlicePointer(valueBytes)
|
|
|
|
err := m.lookup(key, valuePtr, 0)
|
|
if errors.Is(err, ErrKeyNotExist) {
|
|
return nil, nil
|
|
}
|
|
|
|
return valueBytes, err
|
|
}
|
|
|
|
func (m *Map) lookup(key interface{}, valueOut sys.Pointer, flags MapLookupFlags) error {
|
|
keyPtr, err := m.marshalKey(key)
|
|
if err != nil {
|
|
return fmt.Errorf("can't marshal key: %w", err)
|
|
}
|
|
|
|
attr := sys.MapLookupElemAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Key: keyPtr,
|
|
Value: valueOut,
|
|
Flags: uint64(flags),
|
|
}
|
|
|
|
if err = sys.MapLookupElem(&attr); err != nil {
|
|
return fmt.Errorf("lookup: %w", wrapMapError(err))
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (m *Map) lookupAndDelete(key, valueOut interface{}, flags MapLookupFlags) error {
|
|
valuePtr, valueBytes := makeBuffer(valueOut, m.fullValueSize)
|
|
|
|
keyPtr, err := m.marshalKey(key)
|
|
if err != nil {
|
|
return fmt.Errorf("can't marshal key: %w", err)
|
|
}
|
|
|
|
attr := sys.MapLookupAndDeleteElemAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Key: keyPtr,
|
|
Value: valuePtr,
|
|
Flags: uint64(flags),
|
|
}
|
|
|
|
if err := sys.MapLookupAndDeleteElem(&attr); err != nil {
|
|
return fmt.Errorf("lookup and delete: %w", wrapMapError(err))
|
|
}
|
|
|
|
return m.unmarshalValue(valueOut, valueBytes)
|
|
}
|
|
|
|
// MapUpdateFlags controls the behaviour of the Map.Update call.
|
|
//
|
|
// The exact semantics depend on the specific MapType.
|
|
type MapUpdateFlags uint64
|
|
|
|
const (
|
|
// UpdateAny creates a new element or update an existing one.
|
|
UpdateAny MapUpdateFlags = iota
|
|
// UpdateNoExist creates a new element.
|
|
UpdateNoExist MapUpdateFlags = 1 << (iota - 1)
|
|
// UpdateExist updates an existing element.
|
|
UpdateExist
|
|
// UpdateLock updates elements under bpf_spin_lock.
|
|
UpdateLock
|
|
)
|
|
|
|
// Put replaces or creates a value in map.
|
|
//
|
|
// It is equivalent to calling Update with UpdateAny.
|
|
func (m *Map) Put(key, value interface{}) error {
|
|
return m.Update(key, value, UpdateAny)
|
|
}
|
|
|
|
// Update changes the value of a key.
|
|
func (m *Map) Update(key, value interface{}, flags MapUpdateFlags) error {
|
|
keyPtr, err := m.marshalKey(key)
|
|
if err != nil {
|
|
return fmt.Errorf("can't marshal key: %w", err)
|
|
}
|
|
|
|
valuePtr, err := m.marshalValue(value)
|
|
if err != nil {
|
|
return fmt.Errorf("can't marshal value: %w", err)
|
|
}
|
|
|
|
attr := sys.MapUpdateElemAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Key: keyPtr,
|
|
Value: valuePtr,
|
|
Flags: uint64(flags),
|
|
}
|
|
|
|
if err = sys.MapUpdateElem(&attr); err != nil {
|
|
return fmt.Errorf("update: %w", wrapMapError(err))
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Delete removes a value.
|
|
//
|
|
// Returns ErrKeyNotExist if the key does not exist.
|
|
func (m *Map) Delete(key interface{}) error {
|
|
keyPtr, err := m.marshalKey(key)
|
|
if err != nil {
|
|
return fmt.Errorf("can't marshal key: %w", err)
|
|
}
|
|
|
|
attr := sys.MapDeleteElemAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Key: keyPtr,
|
|
}
|
|
|
|
if err = sys.MapDeleteElem(&attr); err != nil {
|
|
return fmt.Errorf("delete: %w", wrapMapError(err))
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// NextKey finds the key following an initial key.
|
|
//
|
|
// See NextKeyBytes for details.
|
|
//
|
|
// Returns ErrKeyNotExist if there is no next key.
|
|
func (m *Map) NextKey(key, nextKeyOut interface{}) error {
|
|
nextKeyPtr, nextKeyBytes := makeBuffer(nextKeyOut, int(m.keySize))
|
|
|
|
if err := m.nextKey(key, nextKeyPtr); err != nil {
|
|
return err
|
|
}
|
|
|
|
if err := m.unmarshalKey(nextKeyOut, nextKeyBytes); err != nil {
|
|
return fmt.Errorf("can't unmarshal next key: %w", err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// NextKeyBytes returns the key following an initial key as a byte slice.
|
|
//
|
|
// Passing nil will return the first key.
|
|
//
|
|
// Use Iterate if you want to traverse all entries in the map.
|
|
//
|
|
// Returns nil if there are no more keys.
|
|
func (m *Map) NextKeyBytes(key interface{}) ([]byte, error) {
|
|
nextKey := make([]byte, m.keySize)
|
|
nextKeyPtr := sys.NewSlicePointer(nextKey)
|
|
|
|
err := m.nextKey(key, nextKeyPtr)
|
|
if errors.Is(err, ErrKeyNotExist) {
|
|
return nil, nil
|
|
}
|
|
|
|
return nextKey, err
|
|
}
|
|
|
|
func (m *Map) nextKey(key interface{}, nextKeyOut sys.Pointer) error {
|
|
var (
|
|
keyPtr sys.Pointer
|
|
err error
|
|
)
|
|
|
|
if key != nil {
|
|
keyPtr, err = m.marshalKey(key)
|
|
if err != nil {
|
|
return fmt.Errorf("can't marshal key: %w", err)
|
|
}
|
|
}
|
|
|
|
attr := sys.MapGetNextKeyAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Key: keyPtr,
|
|
NextKey: nextKeyOut,
|
|
}
|
|
|
|
if err = sys.MapGetNextKey(&attr); err != nil {
|
|
// Kernels 4.4.131 and earlier return EFAULT instead of a pointer to the
|
|
// first map element when a nil key pointer is specified.
|
|
if key == nil && errors.Is(err, unix.EFAULT) {
|
|
var guessKey []byte
|
|
guessKey, err = m.guessNonExistentKey()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
// Retry the syscall with a valid non-existing key.
|
|
attr.Key = sys.NewSlicePointer(guessKey)
|
|
if err = sys.MapGetNextKey(&attr); err == nil {
|
|
return nil
|
|
}
|
|
}
|
|
|
|
return fmt.Errorf("next key: %w", wrapMapError(err))
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// guessNonExistentKey attempts to perform a map lookup that returns ENOENT.
|
|
// This is necessary on kernels before 4.4.132, since those don't support
|
|
// iterating maps from the start by providing an invalid key pointer.
|
|
func (m *Map) guessNonExistentKey() ([]byte, error) {
|
|
// Provide an invalid value pointer to prevent a copy on the kernel side.
|
|
valuePtr := sys.NewPointer(unsafe.Pointer(^uintptr(0)))
|
|
randKey := make([]byte, int(m.keySize))
|
|
|
|
for i := 0; i < 4; i++ {
|
|
switch i {
|
|
// For hash maps, the 0 key is less likely to be occupied. They're often
|
|
// used for storing data related to pointers, and their access pattern is
|
|
// generally scattered across the keyspace.
|
|
case 0:
|
|
// An all-0xff key is guaranteed to be out of bounds of any array, since
|
|
// those have a fixed key size of 4 bytes. The only corner case being
|
|
// arrays with 2^32 max entries, but those are prohibitively expensive
|
|
// in many environments.
|
|
case 1:
|
|
for r := range randKey {
|
|
randKey[r] = 0xff
|
|
}
|
|
// Inspired by BCC, 0x55 is an alternating binary pattern (0101), so
|
|
// is unlikely to be taken.
|
|
case 2:
|
|
for r := range randKey {
|
|
randKey[r] = 0x55
|
|
}
|
|
// Last ditch effort, generate a random key.
|
|
case 3:
|
|
rand.New(rand.NewSource(time.Now().UnixNano())).Read(randKey)
|
|
}
|
|
|
|
err := m.lookup(randKey, valuePtr, 0)
|
|
if errors.Is(err, ErrKeyNotExist) {
|
|
return randKey, nil
|
|
}
|
|
}
|
|
|
|
return nil, errors.New("couldn't find non-existing key")
|
|
}
|
|
|
|
// BatchLookup looks up many elements in a map at once.
|
|
//
|
|
// "keysOut" and "valuesOut" must be of type slice, a pointer
|
|
// to a slice or buffer will not work.
|
|
// "prevKey" is the key to start the batch lookup from, it will
|
|
// *not* be included in the results. Use nil to start at the first key.
|
|
//
|
|
// ErrKeyNotExist is returned when the batch lookup has reached
|
|
// the end of all possible results, even when partial results
|
|
// are returned. It should be used to evaluate when lookup is "done".
|
|
func (m *Map) BatchLookup(prevKey, nextKeyOut, keysOut, valuesOut interface{}, opts *BatchOptions) (int, error) {
|
|
return m.batchLookup(sys.BPF_MAP_LOOKUP_BATCH, prevKey, nextKeyOut, keysOut, valuesOut, opts)
|
|
}
|
|
|
|
// BatchLookupAndDelete looks up many elements in a map at once,
|
|
//
|
|
// It then deletes all those elements.
|
|
// "keysOut" and "valuesOut" must be of type slice, a pointer
|
|
// to a slice or buffer will not work.
|
|
// "prevKey" is the key to start the batch lookup from, it will
|
|
// *not* be included in the results. Use nil to start at the first key.
|
|
//
|
|
// ErrKeyNotExist is returned when the batch lookup has reached
|
|
// the end of all possible results, even when partial results
|
|
// are returned. It should be used to evaluate when lookup is "done".
|
|
func (m *Map) BatchLookupAndDelete(prevKey, nextKeyOut, keysOut, valuesOut interface{}, opts *BatchOptions) (int, error) {
|
|
return m.batchLookup(sys.BPF_MAP_LOOKUP_AND_DELETE_BATCH, prevKey, nextKeyOut, keysOut, valuesOut, opts)
|
|
}
|
|
|
|
func (m *Map) batchLookup(cmd sys.Cmd, startKey, nextKeyOut, keysOut, valuesOut interface{}, opts *BatchOptions) (int, error) {
|
|
if err := haveBatchAPI(); err != nil {
|
|
return 0, err
|
|
}
|
|
if m.typ.hasPerCPUValue() {
|
|
return 0, ErrNotSupported
|
|
}
|
|
keysValue := reflect.ValueOf(keysOut)
|
|
if keysValue.Kind() != reflect.Slice {
|
|
return 0, fmt.Errorf("keys must be a slice")
|
|
}
|
|
valuesValue := reflect.ValueOf(valuesOut)
|
|
if valuesValue.Kind() != reflect.Slice {
|
|
return 0, fmt.Errorf("valuesOut must be a slice")
|
|
}
|
|
count := keysValue.Len()
|
|
if count != valuesValue.Len() {
|
|
return 0, fmt.Errorf("keysOut and valuesOut must be the same length")
|
|
}
|
|
keyBuf := make([]byte, count*int(m.keySize))
|
|
keyPtr := sys.NewSlicePointer(keyBuf)
|
|
valueBuf := make([]byte, count*int(m.fullValueSize))
|
|
valuePtr := sys.NewSlicePointer(valueBuf)
|
|
nextPtr, nextBuf := makeBuffer(nextKeyOut, int(m.keySize))
|
|
|
|
attr := sys.MapLookupBatchAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Keys: keyPtr,
|
|
Values: valuePtr,
|
|
Count: uint32(count),
|
|
OutBatch: nextPtr,
|
|
}
|
|
|
|
if opts != nil {
|
|
attr.ElemFlags = opts.ElemFlags
|
|
attr.Flags = opts.Flags
|
|
}
|
|
|
|
var err error
|
|
if startKey != nil {
|
|
attr.InBatch, err = marshalPtr(startKey, int(m.keySize))
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
}
|
|
|
|
_, sysErr := sys.BPF(cmd, unsafe.Pointer(&attr), unsafe.Sizeof(attr))
|
|
sysErr = wrapMapError(sysErr)
|
|
if sysErr != nil && !errors.Is(sysErr, unix.ENOENT) {
|
|
return 0, sysErr
|
|
}
|
|
|
|
err = m.unmarshalKey(nextKeyOut, nextBuf)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
err = unmarshalBytes(keysOut, keyBuf)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
err = unmarshalBytes(valuesOut, valueBuf)
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
return int(attr.Count), sysErr
|
|
}
|
|
|
|
// BatchUpdate updates the map with multiple keys and values
|
|
// simultaneously.
|
|
// "keys" and "values" must be of type slice, a pointer
|
|
// to a slice or buffer will not work.
|
|
func (m *Map) BatchUpdate(keys, values interface{}, opts *BatchOptions) (int, error) {
|
|
if err := haveBatchAPI(); err != nil {
|
|
return 0, err
|
|
}
|
|
if m.typ.hasPerCPUValue() {
|
|
return 0, ErrNotSupported
|
|
}
|
|
keysValue := reflect.ValueOf(keys)
|
|
if keysValue.Kind() != reflect.Slice {
|
|
return 0, fmt.Errorf("keys must be a slice")
|
|
}
|
|
valuesValue := reflect.ValueOf(values)
|
|
if valuesValue.Kind() != reflect.Slice {
|
|
return 0, fmt.Errorf("values must be a slice")
|
|
}
|
|
var (
|
|
count = keysValue.Len()
|
|
valuePtr sys.Pointer
|
|
err error
|
|
)
|
|
if count != valuesValue.Len() {
|
|
return 0, fmt.Errorf("keys and values must be the same length")
|
|
}
|
|
keyPtr, err := marshalPtr(keys, count*int(m.keySize))
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
valuePtr, err = marshalPtr(values, count*int(m.valueSize))
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
attr := sys.MapUpdateBatchAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Keys: keyPtr,
|
|
Values: valuePtr,
|
|
Count: uint32(count),
|
|
}
|
|
if opts != nil {
|
|
attr.ElemFlags = opts.ElemFlags
|
|
attr.Flags = opts.Flags
|
|
}
|
|
|
|
err = sys.MapUpdateBatch(&attr)
|
|
if err != nil {
|
|
return int(attr.Count), fmt.Errorf("batch update: %w", wrapMapError(err))
|
|
}
|
|
|
|
return int(attr.Count), nil
|
|
}
|
|
|
|
// BatchDelete batch deletes entries in the map by keys.
|
|
// "keys" must be of type slice, a pointer to a slice or buffer will not work.
|
|
func (m *Map) BatchDelete(keys interface{}, opts *BatchOptions) (int, error) {
|
|
if err := haveBatchAPI(); err != nil {
|
|
return 0, err
|
|
}
|
|
if m.typ.hasPerCPUValue() {
|
|
return 0, ErrNotSupported
|
|
}
|
|
keysValue := reflect.ValueOf(keys)
|
|
if keysValue.Kind() != reflect.Slice {
|
|
return 0, fmt.Errorf("keys must be a slice")
|
|
}
|
|
count := keysValue.Len()
|
|
keyPtr, err := marshalPtr(keys, count*int(m.keySize))
|
|
if err != nil {
|
|
return 0, fmt.Errorf("cannot marshal keys: %v", err)
|
|
}
|
|
|
|
attr := sys.MapDeleteBatchAttr{
|
|
MapFd: m.fd.Uint(),
|
|
Keys: keyPtr,
|
|
Count: uint32(count),
|
|
}
|
|
|
|
if opts != nil {
|
|
attr.ElemFlags = opts.ElemFlags
|
|
attr.Flags = opts.Flags
|
|
}
|
|
|
|
if err = sys.MapDeleteBatch(&attr); err != nil {
|
|
return int(attr.Count), fmt.Errorf("batch delete: %w", wrapMapError(err))
|
|
}
|
|
|
|
return int(attr.Count), nil
|
|
}
|
|
|
|
// Iterate traverses a map.
|
|
//
|
|
// It's safe to create multiple iterators at the same time.
|
|
//
|
|
// It's not possible to guarantee that all keys in a map will be
|
|
// returned if there are concurrent modifications to the map.
|
|
func (m *Map) Iterate() *MapIterator {
|
|
return newMapIterator(m)
|
|
}
|
|
|
|
// Close the Map's underlying file descriptor, which could unload the
|
|
// Map from the kernel if it is not pinned or in use by a loaded Program.
|
|
func (m *Map) Close() error {
|
|
if m == nil {
|
|
// This makes it easier to clean up when iterating maps
|
|
// of maps / programs.
|
|
return nil
|
|
}
|
|
|
|
return m.fd.Close()
|
|
}
|
|
|
|
// FD gets the file descriptor of the Map.
|
|
//
|
|
// Calling this function is invalid after Close has been called.
|
|
func (m *Map) FD() int {
|
|
return m.fd.Int()
|
|
}
|
|
|
|
// Clone creates a duplicate of the Map.
|
|
//
|
|
// Closing the duplicate does not affect the original, and vice versa.
|
|
// Changes made to the map are reflected by both instances however.
|
|
// If the original map was pinned, the cloned map will not be pinned by default.
|
|
//
|
|
// Cloning a nil Map returns nil.
|
|
func (m *Map) Clone() (*Map, error) {
|
|
if m == nil {
|
|
return nil, nil
|
|
}
|
|
|
|
dup, err := m.fd.Dup()
|
|
if err != nil {
|
|
return nil, fmt.Errorf("can't clone map: %w", err)
|
|
}
|
|
|
|
return &Map{
|
|
m.name,
|
|
dup,
|
|
m.typ,
|
|
m.keySize,
|
|
m.valueSize,
|
|
m.maxEntries,
|
|
m.flags,
|
|
"",
|
|
m.fullValueSize,
|
|
}, nil
|
|
}
|
|
|
|
// Pin persists the map on the BPF virtual file system past the lifetime of
|
|
// the process that created it .
|
|
//
|
|
// Calling Pin on a previously pinned map will overwrite the path, except when
|
|
// the new path already exists. Re-pinning across filesystems is not supported.
|
|
// You can Clone a map to pin it to a different path.
|
|
//
|
|
// This requires bpffs to be mounted above fileName. See https://docs.cilium.io/en/k8s-doc/admin/#admin-mount-bpffs
|
|
func (m *Map) Pin(fileName string) error {
|
|
if err := internal.Pin(m.pinnedPath, fileName, m.fd); err != nil {
|
|
return err
|
|
}
|
|
m.pinnedPath = fileName
|
|
return nil
|
|
}
|
|
|
|
// Unpin removes the persisted state for the map from the BPF virtual filesystem.
|
|
//
|
|
// Failed calls to Unpin will not alter the state returned by IsPinned.
|
|
//
|
|
// Unpinning an unpinned Map returns nil.
|
|
func (m *Map) Unpin() error {
|
|
if err := internal.Unpin(m.pinnedPath); err != nil {
|
|
return err
|
|
}
|
|
m.pinnedPath = ""
|
|
return nil
|
|
}
|
|
|
|
// IsPinned returns true if the map has a non-empty pinned path.
|
|
func (m *Map) IsPinned() bool {
|
|
return m.pinnedPath != ""
|
|
}
|
|
|
|
// Freeze prevents a map to be modified from user space.
|
|
//
|
|
// It makes no changes to kernel-side restrictions.
|
|
func (m *Map) Freeze() error {
|
|
if err := haveMapMutabilityModifiers(); err != nil {
|
|
return fmt.Errorf("can't freeze map: %w", err)
|
|
}
|
|
|
|
attr := sys.MapFreezeAttr{
|
|
MapFd: m.fd.Uint(),
|
|
}
|
|
|
|
if err := sys.MapFreeze(&attr); err != nil {
|
|
return fmt.Errorf("can't freeze map: %w", err)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// finalize populates the Map according to the Contents specified
|
|
// in spec and freezes the Map if requested by spec.
|
|
func (m *Map) finalize(spec *MapSpec) error {
|
|
for _, kv := range spec.Contents {
|
|
if err := m.Put(kv.Key, kv.Value); err != nil {
|
|
return fmt.Errorf("putting value: key %v: %w", kv.Key, err)
|
|
}
|
|
}
|
|
|
|
if spec.Freeze {
|
|
if err := m.Freeze(); err != nil {
|
|
return fmt.Errorf("freezing map: %w", err)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (m *Map) marshalKey(data interface{}) (sys.Pointer, error) {
|
|
if data == nil {
|
|
if m.keySize == 0 {
|
|
// Queues have a key length of zero, so passing nil here is valid.
|
|
return sys.NewPointer(nil), nil
|
|
}
|
|
return sys.Pointer{}, errors.New("can't use nil as key of map")
|
|
}
|
|
|
|
return marshalPtr(data, int(m.keySize))
|
|
}
|
|
|
|
func (m *Map) unmarshalKey(data interface{}, buf []byte) error {
|
|
if buf == nil {
|
|
// This is from a makeBuffer call, nothing do do here.
|
|
return nil
|
|
}
|
|
|
|
return unmarshalBytes(data, buf)
|
|
}
|
|
|
|
func (m *Map) marshalValue(data interface{}) (sys.Pointer, error) {
|
|
if m.typ.hasPerCPUValue() {
|
|
return marshalPerCPUValue(data, int(m.valueSize))
|
|
}
|
|
|
|
var (
|
|
buf []byte
|
|
err error
|
|
)
|
|
|
|
switch value := data.(type) {
|
|
case *Map:
|
|
if !m.typ.canStoreMap() {
|
|
return sys.Pointer{}, fmt.Errorf("can't store map in %s", m.typ)
|
|
}
|
|
buf, err = marshalMap(value, int(m.valueSize))
|
|
|
|
case *Program:
|
|
if !m.typ.canStoreProgram() {
|
|
return sys.Pointer{}, fmt.Errorf("can't store program in %s", m.typ)
|
|
}
|
|
buf, err = marshalProgram(value, int(m.valueSize))
|
|
|
|
default:
|
|
return marshalPtr(data, int(m.valueSize))
|
|
}
|
|
|
|
if err != nil {
|
|
return sys.Pointer{}, err
|
|
}
|
|
|
|
return sys.NewSlicePointer(buf), nil
|
|
}
|
|
|
|
func (m *Map) unmarshalValue(value interface{}, buf []byte) error {
|
|
if buf == nil {
|
|
// This is from a makeBuffer call, nothing do do here.
|
|
return nil
|
|
}
|
|
|
|
if m.typ.hasPerCPUValue() {
|
|
return unmarshalPerCPUValue(value, int(m.valueSize), buf)
|
|
}
|
|
|
|
switch value := value.(type) {
|
|
case **Map:
|
|
if !m.typ.canStoreMap() {
|
|
return fmt.Errorf("can't read a map from %s", m.typ)
|
|
}
|
|
|
|
other, err := unmarshalMap(buf)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
// The caller might close the map externally, so ignore errors.
|
|
_ = (*value).Close()
|
|
|
|
*value = other
|
|
return nil
|
|
|
|
case *Map:
|
|
if !m.typ.canStoreMap() {
|
|
return fmt.Errorf("can't read a map from %s", m.typ)
|
|
}
|
|
return errors.New("require pointer to *Map")
|
|
|
|
case **Program:
|
|
if !m.typ.canStoreProgram() {
|
|
return fmt.Errorf("can't read a program from %s", m.typ)
|
|
}
|
|
|
|
other, err := unmarshalProgram(buf)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
// The caller might close the program externally, so ignore errors.
|
|
_ = (*value).Close()
|
|
|
|
*value = other
|
|
return nil
|
|
|
|
case *Program:
|
|
if !m.typ.canStoreProgram() {
|
|
return fmt.Errorf("can't read a program from %s", m.typ)
|
|
}
|
|
return errors.New("require pointer to *Program")
|
|
}
|
|
|
|
return unmarshalBytes(value, buf)
|
|
}
|
|
|
|
// LoadPinnedMap loads a Map from a BPF file.
|
|
func LoadPinnedMap(fileName string, opts *LoadPinOptions) (*Map, error) {
|
|
fd, err := sys.ObjGet(&sys.ObjGetAttr{
|
|
Pathname: sys.NewStringPointer(fileName),
|
|
FileFlags: opts.Marshal(),
|
|
})
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
m, err := newMapFromFD(fd)
|
|
if err == nil {
|
|
m.pinnedPath = fileName
|
|
}
|
|
|
|
return m, err
|
|
}
|
|
|
|
// unmarshalMap creates a map from a map ID encoded in host endianness.
|
|
func unmarshalMap(buf []byte) (*Map, error) {
|
|
if len(buf) != 4 {
|
|
return nil, errors.New("map id requires 4 byte value")
|
|
}
|
|
|
|
id := internal.NativeEndian.Uint32(buf)
|
|
return NewMapFromID(MapID(id))
|
|
}
|
|
|
|
// marshalMap marshals the fd of a map into a buffer in host endianness.
|
|
func marshalMap(m *Map, length int) ([]byte, error) {
|
|
if length != 4 {
|
|
return nil, fmt.Errorf("can't marshal map to %d bytes", length)
|
|
}
|
|
|
|
buf := make([]byte, 4)
|
|
internal.NativeEndian.PutUint32(buf, m.fd.Uint())
|
|
return buf, nil
|
|
}
|
|
|
|
// MapIterator iterates a Map.
|
|
//
|
|
// See Map.Iterate.
|
|
type MapIterator struct {
|
|
target *Map
|
|
prevKey interface{}
|
|
prevBytes []byte
|
|
count, maxEntries uint32
|
|
done bool
|
|
err error
|
|
}
|
|
|
|
func newMapIterator(target *Map) *MapIterator {
|
|
return &MapIterator{
|
|
target: target,
|
|
maxEntries: target.maxEntries,
|
|
prevBytes: make([]byte, target.keySize),
|
|
}
|
|
}
|
|
|
|
// Next decodes the next key and value.
|
|
//
|
|
// Iterating a hash map from which keys are being deleted is not
|
|
// safe. You may see the same key multiple times. Iteration may
|
|
// also abort with an error, see IsIterationAborted.
|
|
//
|
|
// Returns false if there are no more entries. You must check
|
|
// the result of Err afterwards.
|
|
//
|
|
// See Map.Get for further caveats around valueOut.
|
|
func (mi *MapIterator) Next(keyOut, valueOut interface{}) bool {
|
|
if mi.err != nil || mi.done {
|
|
return false
|
|
}
|
|
|
|
// For array-like maps NextKeyBytes returns nil only on after maxEntries
|
|
// iterations.
|
|
for mi.count <= mi.maxEntries {
|
|
var nextBytes []byte
|
|
nextBytes, mi.err = mi.target.NextKeyBytes(mi.prevKey)
|
|
if mi.err != nil {
|
|
return false
|
|
}
|
|
|
|
if nextBytes == nil {
|
|
mi.done = true
|
|
return false
|
|
}
|
|
|
|
// The user can get access to nextBytes since unmarshalBytes
|
|
// does not copy when unmarshaling into a []byte.
|
|
// Make a copy to prevent accidental corruption of
|
|
// iterator state.
|
|
copy(mi.prevBytes, nextBytes)
|
|
mi.prevKey = mi.prevBytes
|
|
|
|
mi.count++
|
|
mi.err = mi.target.Lookup(nextBytes, valueOut)
|
|
if errors.Is(mi.err, ErrKeyNotExist) {
|
|
// Even though the key should be valid, we couldn't look up
|
|
// its value. If we're iterating a hash map this is probably
|
|
// because a concurrent delete removed the value before we
|
|
// could get it. This means that the next call to NextKeyBytes
|
|
// is very likely to restart iteration.
|
|
// If we're iterating one of the fd maps like
|
|
// ProgramArray it means that a given slot doesn't have
|
|
// a valid fd associated. It's OK to continue to the next slot.
|
|
continue
|
|
}
|
|
if mi.err != nil {
|
|
return false
|
|
}
|
|
|
|
mi.err = mi.target.unmarshalKey(keyOut, nextBytes)
|
|
return mi.err == nil
|
|
}
|
|
|
|
mi.err = fmt.Errorf("%w", ErrIterationAborted)
|
|
return false
|
|
}
|
|
|
|
// Err returns any encountered error.
|
|
//
|
|
// The method must be called after Next returns nil.
|
|
//
|
|
// Returns ErrIterationAborted if it wasn't possible to do a full iteration.
|
|
func (mi *MapIterator) Err() error {
|
|
return mi.err
|
|
}
|
|
|
|
// MapGetNextID returns the ID of the next eBPF map.
|
|
//
|
|
// Returns ErrNotExist, if there is no next eBPF map.
|
|
func MapGetNextID(startID MapID) (MapID, error) {
|
|
attr := &sys.MapGetNextIdAttr{Id: uint32(startID)}
|
|
return MapID(attr.NextId), sys.MapGetNextId(attr)
|
|
}
|
|
|
|
// NewMapFromID returns the map for a given id.
|
|
//
|
|
// Returns ErrNotExist, if there is no eBPF map with the given id.
|
|
func NewMapFromID(id MapID) (*Map, error) {
|
|
fd, err := sys.MapGetFdById(&sys.MapGetFdByIdAttr{
|
|
Id: uint32(id),
|
|
})
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return newMapFromFD(fd)
|
|
}
|