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path: root/vendor/github.com/cilium/ebpf/collection.go
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-rw-r--r--vendor/github.com/cilium/ebpf/collection.go772
1 files changed, 0 insertions, 772 deletions
diff --git a/vendor/github.com/cilium/ebpf/collection.go b/vendor/github.com/cilium/ebpf/collection.go
deleted file mode 100644
index 8c2ddc380..000000000
--- a/vendor/github.com/cilium/ebpf/collection.go
+++ /dev/null
@@ -1,772 +0,0 @@
-package ebpf
-
-import (
- "encoding/binary"
- "errors"
- "fmt"
- "reflect"
- "strings"
-
- "github.com/cilium/ebpf/asm"
- "github.com/cilium/ebpf/btf"
-)
-
-// CollectionOptions control loading a collection into the kernel.
-//
-// Maps and Programs are passed to NewMapWithOptions and NewProgramsWithOptions.
-type CollectionOptions struct {
- Maps MapOptions
- Programs ProgramOptions
-
- // MapReplacements takes a set of Maps that will be used instead of
- // creating new ones when loading the CollectionSpec.
- //
- // For each given Map, there must be a corresponding MapSpec in
- // CollectionSpec.Maps, and its type, key/value size, max entries and flags
- // must match the values of the MapSpec.
- //
- // The given Maps are Clone()d before being used in the Collection, so the
- // caller can Close() them freely when they are no longer needed.
- MapReplacements map[string]*Map
-}
-
-// CollectionSpec describes a collection.
-type CollectionSpec struct {
- Maps map[string]*MapSpec
- Programs map[string]*ProgramSpec
-
- // Types holds type information about Maps and Programs.
- // Modifications to Types are currently undefined behaviour.
- Types *btf.Spec
-
- // ByteOrder specifies whether the ELF was compiled for
- // big-endian or little-endian architectures.
- ByteOrder binary.ByteOrder
-}
-
-// Copy returns a recursive copy of the spec.
-func (cs *CollectionSpec) Copy() *CollectionSpec {
- if cs == nil {
- return nil
- }
-
- cpy := CollectionSpec{
- Maps: make(map[string]*MapSpec, len(cs.Maps)),
- Programs: make(map[string]*ProgramSpec, len(cs.Programs)),
- ByteOrder: cs.ByteOrder,
- Types: cs.Types,
- }
-
- for name, spec := range cs.Maps {
- cpy.Maps[name] = spec.Copy()
- }
-
- for name, spec := range cs.Programs {
- cpy.Programs[name] = spec.Copy()
- }
-
- return &cpy
-}
-
-// RewriteMaps replaces all references to specific maps.
-//
-// Use this function to use pre-existing maps instead of creating new ones
-// when calling NewCollection. Any named maps are removed from CollectionSpec.Maps.
-//
-// Returns an error if a named map isn't used in at least one program.
-//
-// Deprecated: Pass CollectionOptions.MapReplacements when loading the Collection
-// instead.
-func (cs *CollectionSpec) RewriteMaps(maps map[string]*Map) error {
- for symbol, m := range maps {
- // have we seen a program that uses this symbol / map
- seen := false
- for progName, progSpec := range cs.Programs {
- err := progSpec.Instructions.AssociateMap(symbol, m)
-
- switch {
- case err == nil:
- seen = true
-
- case errors.Is(err, asm.ErrUnreferencedSymbol):
- // Not all programs need to use the map
-
- default:
- return fmt.Errorf("program %s: %w", progName, err)
- }
- }
-
- if !seen {
- return fmt.Errorf("map %s not referenced by any programs", symbol)
- }
-
- // Prevent NewCollection from creating rewritten maps
- delete(cs.Maps, symbol)
- }
-
- return nil
-}
-
-// RewriteConstants replaces the value of multiple constants.
-//
-// The constant must be defined like so in the C program:
-//
-// volatile const type foobar;
-// volatile const type foobar = default;
-//
-// Replacement values must be of the same length as the C sizeof(type).
-// If necessary, they are marshalled according to the same rules as
-// map values.
-//
-// From Linux 5.5 the verifier will use constants to eliminate dead code.
-//
-// Returns an error if a constant doesn't exist.
-func (cs *CollectionSpec) RewriteConstants(consts map[string]interface{}) error {
- replaced := make(map[string]bool)
-
- for name, spec := range cs.Maps {
- if !strings.HasPrefix(name, ".rodata") {
- continue
- }
-
- b, ds, err := spec.dataSection()
- if errors.Is(err, errMapNoBTFValue) {
- // Data sections without a BTF Datasec are valid, but don't support
- // constant replacements.
- continue
- }
- if err != nil {
- return fmt.Errorf("map %s: %w", name, err)
- }
-
- // MapSpec.Copy() performs a shallow copy. Fully copy the byte slice
- // to avoid any changes affecting other copies of the MapSpec.
- cpy := make([]byte, len(b))
- copy(cpy, b)
-
- for _, v := range ds.Vars {
- vname := v.Type.TypeName()
- replacement, ok := consts[vname]
- if !ok {
- continue
- }
-
- if replaced[vname] {
- return fmt.Errorf("section %s: duplicate variable %s", name, vname)
- }
-
- if int(v.Offset+v.Size) > len(cpy) {
- return fmt.Errorf("section %s: offset %d(+%d) for variable %s is out of bounds", name, v.Offset, v.Size, vname)
- }
-
- b, err := marshalBytes(replacement, int(v.Size))
- if err != nil {
- return fmt.Errorf("marshaling constant replacement %s: %w", vname, err)
- }
-
- copy(cpy[v.Offset:v.Offset+v.Size], b)
-
- replaced[vname] = true
- }
-
- spec.Contents[0] = MapKV{Key: uint32(0), Value: cpy}
- }
-
- var missing []string
- for c := range consts {
- if !replaced[c] {
- missing = append(missing, c)
- }
- }
-
- if len(missing) != 0 {
- return fmt.Errorf("spec is missing one or more constants: %s", strings.Join(missing, ","))
- }
-
- return nil
-}
-
-// Assign the contents of a CollectionSpec to a struct.
-//
-// This function is a shortcut to manually checking the presence
-// of maps and programs in a CollectionSpec. Consider using bpf2go
-// if this sounds useful.
-//
-// 'to' must be a pointer to a struct. A field of the
-// struct is updated with values from Programs or Maps if it
-// has an `ebpf` tag and its type is *ProgramSpec or *MapSpec.
-// The tag's value specifies the name of the program or map as
-// found in the CollectionSpec.
-//
-// struct {
-// Foo *ebpf.ProgramSpec `ebpf:"xdp_foo"`
-// Bar *ebpf.MapSpec `ebpf:"bar_map"`
-// Ignored int
-// }
-//
-// Returns an error if any of the eBPF objects can't be found, or
-// if the same MapSpec or ProgramSpec is assigned multiple times.
-func (cs *CollectionSpec) Assign(to interface{}) error {
- // Assign() only supports assigning ProgramSpecs and MapSpecs,
- // so doesn't load any resources into the kernel.
- getValue := func(typ reflect.Type, name string) (interface{}, error) {
- switch typ {
-
- case reflect.TypeOf((*ProgramSpec)(nil)):
- if p := cs.Programs[name]; p != nil {
- return p, nil
- }
- return nil, fmt.Errorf("missing program %q", name)
-
- case reflect.TypeOf((*MapSpec)(nil)):
- if m := cs.Maps[name]; m != nil {
- return m, nil
- }
- return nil, fmt.Errorf("missing map %q", name)
-
- default:
- return nil, fmt.Errorf("unsupported type %s", typ)
- }
- }
-
- return assignValues(to, getValue)
-}
-
-// LoadAndAssign loads Maps and Programs into the kernel and assigns them
-// to a struct.
-//
-// Omitting Map/Program.Close() during application shutdown is an error.
-// See the package documentation for details around Map and Program lifecycle.
-//
-// This function is a shortcut to manually checking the presence
-// of maps and programs in a CollectionSpec. Consider using bpf2go
-// if this sounds useful.
-//
-// 'to' must be a pointer to a struct. A field of the struct is updated with
-// a Program or Map if it has an `ebpf` tag and its type is *Program or *Map.
-// The tag's value specifies the name of the program or map as found in the
-// CollectionSpec. Before updating the struct, the requested objects and their
-// dependent resources are loaded into the kernel and populated with values if
-// specified.
-//
-// struct {
-// Foo *ebpf.Program `ebpf:"xdp_foo"`
-// Bar *ebpf.Map `ebpf:"bar_map"`
-// Ignored int
-// }
-//
-// opts may be nil.
-//
-// Returns an error if any of the fields can't be found, or
-// if the same Map or Program is assigned multiple times.
-func (cs *CollectionSpec) LoadAndAssign(to interface{}, opts *CollectionOptions) error {
- loader, err := newCollectionLoader(cs, opts)
- if err != nil {
- return err
- }
- defer loader.close()
-
- // Support assigning Programs and Maps, lazy-loading the required objects.
- assignedMaps := make(map[string]bool)
- assignedProgs := make(map[string]bool)
-
- getValue := func(typ reflect.Type, name string) (interface{}, error) {
- switch typ {
-
- case reflect.TypeOf((*Program)(nil)):
- assignedProgs[name] = true
- return loader.loadProgram(name)
-
- case reflect.TypeOf((*Map)(nil)):
- assignedMaps[name] = true
- return loader.loadMap(name)
-
- default:
- return nil, fmt.Errorf("unsupported type %s", typ)
- }
- }
-
- // Load the Maps and Programs requested by the annotated struct.
- if err := assignValues(to, getValue); err != nil {
- return err
- }
-
- // Populate the requested maps. Has a chance of lazy-loading other dependent maps.
- if err := loader.populateMaps(); err != nil {
- return err
- }
-
- // Evaluate the loader's objects after all (lazy)loading has taken place.
- for n, m := range loader.maps {
- switch m.typ {
- case ProgramArray:
- // Require all lazy-loaded ProgramArrays to be assigned to the given object.
- // The kernel empties a ProgramArray once the last user space reference
- // to it closes, which leads to failed tail calls. Combined with the library
- // closing map fds via GC finalizers this can lead to surprising behaviour.
- // Only allow unassigned ProgramArrays when the library hasn't pre-populated
- // any entries from static value declarations. At this point, we know the map
- // is empty and there's no way for the caller to interact with the map going
- // forward.
- if !assignedMaps[n] && len(cs.Maps[n].Contents) > 0 {
- return fmt.Errorf("ProgramArray %s must be assigned to prevent missed tail calls", n)
- }
- }
- }
-
- // Prevent loader.cleanup() from closing assigned Maps and Programs.
- for m := range assignedMaps {
- delete(loader.maps, m)
- }
- for p := range assignedProgs {
- delete(loader.programs, p)
- }
-
- return nil
-}
-
-// Collection is a collection of Programs and Maps associated
-// with their symbols
-type Collection struct {
- Programs map[string]*Program
- Maps map[string]*Map
-}
-
-// NewCollection creates a Collection from the given spec, creating and
-// loading its declared resources into the kernel.
-//
-// Omitting Collection.Close() during application shutdown is an error.
-// See the package documentation for details around Map and Program lifecycle.
-func NewCollection(spec *CollectionSpec) (*Collection, error) {
- return NewCollectionWithOptions(spec, CollectionOptions{})
-}
-
-// NewCollectionWithOptions creates a Collection from the given spec using
-// options, creating and loading its declared resources into the kernel.
-//
-// Omitting Collection.Close() during application shutdown is an error.
-// See the package documentation for details around Map and Program lifecycle.
-func NewCollectionWithOptions(spec *CollectionSpec, opts CollectionOptions) (*Collection, error) {
- loader, err := newCollectionLoader(spec, &opts)
- if err != nil {
- return nil, err
- }
- defer loader.close()
-
- // Create maps first, as their fds need to be linked into programs.
- for mapName := range spec.Maps {
- if _, err := loader.loadMap(mapName); err != nil {
- return nil, err
- }
- }
-
- for progName, prog := range spec.Programs {
- if prog.Type == UnspecifiedProgram {
- continue
- }
-
- if _, err := loader.loadProgram(progName); err != nil {
- return nil, err
- }
- }
-
- // Maps can contain Program and Map stubs, so populate them after
- // all Maps and Programs have been successfully loaded.
- if err := loader.populateMaps(); err != nil {
- return nil, err
- }
-
- // Prevent loader.cleanup from closing maps and programs.
- maps, progs := loader.maps, loader.programs
- loader.maps, loader.programs = nil, nil
-
- return &Collection{
- progs,
- maps,
- }, nil
-}
-
-type handleCache struct {
- btfHandles map[*btf.Spec]*btf.Handle
-}
-
-func newHandleCache() *handleCache {
- return &handleCache{
- btfHandles: make(map[*btf.Spec]*btf.Handle),
- }
-}
-
-func (hc handleCache) btfHandle(spec *btf.Spec) (*btf.Handle, error) {
- if hc.btfHandles[spec] != nil {
- return hc.btfHandles[spec], nil
- }
-
- handle, err := btf.NewHandle(spec)
- if err != nil {
- return nil, err
- }
-
- hc.btfHandles[spec] = handle
- return handle, nil
-}
-
-func (hc handleCache) close() {
- for _, handle := range hc.btfHandles {
- handle.Close()
- }
-}
-
-type collectionLoader struct {
- coll *CollectionSpec
- opts *CollectionOptions
- maps map[string]*Map
- programs map[string]*Program
- handles *handleCache
-}
-
-func newCollectionLoader(coll *CollectionSpec, opts *CollectionOptions) (*collectionLoader, error) {
- if opts == nil {
- opts = &CollectionOptions{}
- }
-
- // Check for existing MapSpecs in the CollectionSpec for all provided replacement maps.
- for name, m := range opts.MapReplacements {
- spec, ok := coll.Maps[name]
- if !ok {
- return nil, fmt.Errorf("replacement map %s not found in CollectionSpec", name)
- }
-
- if err := spec.checkCompatibility(m); err != nil {
- return nil, fmt.Errorf("using replacement map %s: %w", spec.Name, err)
- }
- }
-
- return &collectionLoader{
- coll,
- opts,
- make(map[string]*Map),
- make(map[string]*Program),
- newHandleCache(),
- }, nil
-}
-
-// close all resources left over in the collectionLoader.
-func (cl *collectionLoader) close() {
- cl.handles.close()
- for _, m := range cl.maps {
- m.Close()
- }
- for _, p := range cl.programs {
- p.Close()
- }
-}
-
-func (cl *collectionLoader) loadMap(mapName string) (*Map, error) {
- if m := cl.maps[mapName]; m != nil {
- return m, nil
- }
-
- mapSpec := cl.coll.Maps[mapName]
- if mapSpec == nil {
- return nil, fmt.Errorf("missing map %s", mapName)
- }
-
- if mapSpec.BTF != nil && cl.coll.Types != mapSpec.BTF {
- return nil, fmt.Errorf("map %s: BTF doesn't match collection", mapName)
- }
-
- if replaceMap, ok := cl.opts.MapReplacements[mapName]; ok {
- // Clone the map to avoid closing user's map later on.
- m, err := replaceMap.Clone()
- if err != nil {
- return nil, err
- }
-
- cl.maps[mapName] = m
- return m, nil
- }
-
- m, err := newMapWithOptions(mapSpec, cl.opts.Maps, cl.handles)
- if err != nil {
- return nil, fmt.Errorf("map %s: %w", mapName, err)
- }
-
- cl.maps[mapName] = m
- return m, nil
-}
-
-func (cl *collectionLoader) loadProgram(progName string) (*Program, error) {
- if prog := cl.programs[progName]; prog != nil {
- return prog, nil
- }
-
- progSpec := cl.coll.Programs[progName]
- if progSpec == nil {
- return nil, fmt.Errorf("unknown program %s", progName)
- }
-
- // Bail out early if we know the kernel is going to reject the program.
- // This skips loading map dependencies, saving some cleanup work later.
- if progSpec.Type == UnspecifiedProgram {
- return nil, fmt.Errorf("cannot load program %s: program type is unspecified", progName)
- }
-
- if progSpec.BTF != nil && cl.coll.Types != progSpec.BTF {
- return nil, fmt.Errorf("program %s: BTF doesn't match collection", progName)
- }
-
- progSpec = progSpec.Copy()
-
- // Rewrite any reference to a valid map in the program's instructions,
- // which includes all of its dependencies.
- for i := range progSpec.Instructions {
- ins := &progSpec.Instructions[i]
-
- if !ins.IsLoadFromMap() || ins.Reference() == "" {
- continue
- }
-
- // Don't overwrite map loads containing non-zero map fd's,
- // they can be manually included by the caller.
- // Map FDs/IDs are placed in the lower 32 bits of Constant.
- if int32(ins.Constant) > 0 {
- continue
- }
-
- m, err := cl.loadMap(ins.Reference())
- if err != nil {
- return nil, fmt.Errorf("program %s: %w", progName, err)
- }
-
- if err := ins.AssociateMap(m); err != nil {
- return nil, fmt.Errorf("program %s: map %s: %w", progName, ins.Reference(), err)
- }
- }
-
- prog, err := newProgramWithOptions(progSpec, cl.opts.Programs, cl.handles)
- if err != nil {
- return nil, fmt.Errorf("program %s: %w", progName, err)
- }
-
- cl.programs[progName] = prog
- return prog, nil
-}
-
-func (cl *collectionLoader) populateMaps() error {
- for mapName, m := range cl.maps {
- mapSpec, ok := cl.coll.Maps[mapName]
- if !ok {
- return fmt.Errorf("missing map spec %s", mapName)
- }
-
- mapSpec = mapSpec.Copy()
-
- // MapSpecs that refer to inner maps or programs within the same
- // CollectionSpec do so using strings. These strings are used as the key
- // to look up the respective object in the Maps or Programs fields.
- // Resolve those references to actual Map or Program resources that
- // have been loaded into the kernel.
- for i, kv := range mapSpec.Contents {
- if objName, ok := kv.Value.(string); ok {
- switch mapSpec.Type {
- case ProgramArray:
- // loadProgram is idempotent and could return an existing Program.
- prog, err := cl.loadProgram(objName)
- if err != nil {
- return fmt.Errorf("loading program %s, for map %s: %w", objName, mapName, err)
- }
- mapSpec.Contents[i] = MapKV{kv.Key, prog}
-
- case ArrayOfMaps, HashOfMaps:
- // loadMap is idempotent and could return an existing Map.
- innerMap, err := cl.loadMap(objName)
- if err != nil {
- return fmt.Errorf("loading inner map %s, for map %s: %w", objName, mapName, err)
- }
- mapSpec.Contents[i] = MapKV{kv.Key, innerMap}
- }
- }
- }
-
- // Populate and freeze the map if specified.
- if err := m.finalize(mapSpec); err != nil {
- return fmt.Errorf("populating map %s: %w", mapName, err)
- }
- }
-
- return nil
-}
-
-// LoadCollection reads an object file and creates and loads its declared
-// resources into the kernel.
-//
-// Omitting Collection.Close() during application shutdown is an error.
-// See the package documentation for details around Map and Program lifecycle.
-func LoadCollection(file string) (*Collection, error) {
- spec, err := LoadCollectionSpec(file)
- if err != nil {
- return nil, err
- }
- return NewCollection(spec)
-}
-
-// Close frees all maps and programs associated with the collection.
-//
-// The collection mustn't be used afterwards.
-func (coll *Collection) Close() {
- for _, prog := range coll.Programs {
- prog.Close()
- }
- for _, m := range coll.Maps {
- m.Close()
- }
-}
-
-// DetachMap removes the named map from the Collection.
-//
-// This means that a later call to Close() will not affect this map.
-//
-// Returns nil if no map of that name exists.
-func (coll *Collection) DetachMap(name string) *Map {
- m := coll.Maps[name]
- delete(coll.Maps, name)
- return m
-}
-
-// DetachProgram removes the named program from the Collection.
-//
-// This means that a later call to Close() will not affect this program.
-//
-// Returns nil if no program of that name exists.
-func (coll *Collection) DetachProgram(name string) *Program {
- p := coll.Programs[name]
- delete(coll.Programs, name)
- return p
-}
-
-// structField represents a struct field containing the ebpf struct tag.
-type structField struct {
- reflect.StructField
- value reflect.Value
-}
-
-// ebpfFields extracts field names tagged with 'ebpf' from a struct type.
-// Keep track of visited types to avoid infinite recursion.
-func ebpfFields(structVal reflect.Value, visited map[reflect.Type]bool) ([]structField, error) {
- if visited == nil {
- visited = make(map[reflect.Type]bool)
- }
-
- structType := structVal.Type()
- if structType.Kind() != reflect.Struct {
- return nil, fmt.Errorf("%s is not a struct", structType)
- }
-
- if visited[structType] {
- return nil, fmt.Errorf("recursion on type %s", structType)
- }
-
- fields := make([]structField, 0, structType.NumField())
- for i := 0; i < structType.NumField(); i++ {
- field := structField{structType.Field(i), structVal.Field(i)}
-
- // If the field is tagged, gather it and move on.
- name := field.Tag.Get("ebpf")
- if name != "" {
- fields = append(fields, field)
- continue
- }
-
- // If the field does not have an ebpf tag, but is a struct or a pointer
- // to a struct, attempt to gather its fields as well.
- var v reflect.Value
- switch field.Type.Kind() {
- case reflect.Ptr:
- if field.Type.Elem().Kind() != reflect.Struct {
- continue
- }
-
- if field.value.IsNil() {
- return nil, fmt.Errorf("nil pointer to %s", structType)
- }
-
- // Obtain the destination type of the pointer.
- v = field.value.Elem()
-
- case reflect.Struct:
- // Reference the value's type directly.
- v = field.value
-
- default:
- continue
- }
-
- inner, err := ebpfFields(v, visited)
- if err != nil {
- return nil, fmt.Errorf("field %s: %w", field.Name, err)
- }
-
- fields = append(fields, inner...)
- }
-
- return fields, nil
-}
-
-// assignValues attempts to populate all fields of 'to' tagged with 'ebpf'.
-//
-// getValue is called for every tagged field of 'to' and must return the value
-// to be assigned to the field with the given typ and name.
-func assignValues(to interface{},
- getValue func(typ reflect.Type, name string) (interface{}, error)) error {
-
- toValue := reflect.ValueOf(to)
- if toValue.Type().Kind() != reflect.Ptr {
- return fmt.Errorf("%T is not a pointer to struct", to)
- }
-
- if toValue.IsNil() {
- return fmt.Errorf("nil pointer to %T", to)
- }
-
- fields, err := ebpfFields(toValue.Elem(), nil)
- if err != nil {
- return err
- }
-
- type elem struct {
- // Either *Map or *Program
- typ reflect.Type
- name string
- }
-
- assigned := make(map[elem]string)
- for _, field := range fields {
- // Get string value the field is tagged with.
- tag := field.Tag.Get("ebpf")
- if strings.Contains(tag, ",") {
- return fmt.Errorf("field %s: ebpf tag contains a comma", field.Name)
- }
-
- // Check if the eBPF object with the requested
- // type and tag was already assigned elsewhere.
- e := elem{field.Type, tag}
- if af := assigned[e]; af != "" {
- return fmt.Errorf("field %s: object %q was already assigned to %s", field.Name, tag, af)
- }
-
- // Get the eBPF object referred to by the tag.
- value, err := getValue(field.Type, tag)
- if err != nil {
- return fmt.Errorf("field %s: %w", field.Name, err)
- }
-
- if !field.value.CanSet() {
- return fmt.Errorf("field %s: can't set value", field.Name)
- }
- field.value.Set(reflect.ValueOf(value))
-
- assigned[e] = field.Name
- }
-
- return nil
-}
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-13 01:17:08 +0000