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-rw-r--r--vendor/github.com/cilium/ebpf/link/tracing.go141
1 files changed, 141 insertions, 0 deletions
diff --git a/vendor/github.com/cilium/ebpf/link/tracing.go b/vendor/github.com/cilium/ebpf/link/tracing.go
new file mode 100644
index 000000000..e47e61a3b
--- /dev/null
+++ b/vendor/github.com/cilium/ebpf/link/tracing.go
@@ -0,0 +1,141 @@
+package link
+
+import (
+ "fmt"
+
+ "github.com/cilium/ebpf"
+ "github.com/cilium/ebpf/btf"
+ "github.com/cilium/ebpf/internal/sys"
+)
+
+type tracing struct {
+ RawLink
+}
+
+func (f *tracing) Update(new *ebpf.Program) error {
+ return fmt.Errorf("tracing update: %w", ErrNotSupported)
+}
+
+// AttachFreplace attaches the given eBPF program to the function it replaces.
+//
+// The program and name can either be provided at link time, or can be provided
+// at program load time. If they were provided at load time, they should be nil
+// and empty respectively here, as they will be ignored by the kernel.
+// Examples:
+//
+// AttachFreplace(dispatcher, "function", replacement)
+// AttachFreplace(nil, "", replacement)
+func AttachFreplace(targetProg *ebpf.Program, name string, prog *ebpf.Program) (Link, error) {
+ if (name == "") != (targetProg == nil) {
+ return nil, fmt.Errorf("must provide both or neither of name and targetProg: %w", errInvalidInput)
+ }
+ if prog == nil {
+ return nil, fmt.Errorf("prog cannot be nil: %w", errInvalidInput)
+ }
+ if prog.Type() != ebpf.Extension {
+ return nil, fmt.Errorf("eBPF program type %s is not an Extension: %w", prog.Type(), errInvalidInput)
+ }
+
+ var (
+ target int
+ typeID btf.TypeID
+ )
+ if targetProg != nil {
+ btfHandle, err := targetProg.Handle()
+ if err != nil {
+ return nil, err
+ }
+ defer btfHandle.Close()
+
+ spec, err := btfHandle.Spec(nil)
+ if err != nil {
+ return nil, err
+ }
+
+ var function *btf.Func
+ if err := spec.TypeByName(name, &function); err != nil {
+ return nil, err
+ }
+
+ target = targetProg.FD()
+ typeID, err = spec.TypeID(function)
+ if err != nil {
+ return nil, err
+ }
+ }
+
+ link, err := AttachRawLink(RawLinkOptions{
+ Target: target,
+ Program: prog,
+ Attach: ebpf.AttachNone,
+ BTF: typeID,
+ })
+ if err != nil {
+ return nil, err
+ }
+
+ return &tracing{*link}, nil
+}
+
+type TracingOptions struct {
+ // Program must be of type Tracing with attach type
+ // AttachTraceFEntry/AttachTraceFExit/AttachModifyReturn or
+ // AttachTraceRawTp.
+ Program *ebpf.Program
+}
+
+type LSMOptions struct {
+ // Program must be of type LSM with attach type
+ // AttachLSMMac.
+ Program *ebpf.Program
+}
+
+// attachBTFID links all BPF program types (Tracing/LSM) that they attach to a btf_id.
+func attachBTFID(program *ebpf.Program) (Link, error) {
+ if program.FD() < 0 {
+ return nil, fmt.Errorf("invalid program %w", sys.ErrClosedFd)
+ }
+
+ fd, err := sys.RawTracepointOpen(&sys.RawTracepointOpenAttr{
+ ProgFd: uint32(program.FD()),
+ })
+ if err != nil {
+ return nil, err
+ }
+
+ raw := RawLink{fd: fd}
+ info, err := raw.Info()
+ if err != nil {
+ raw.Close()
+ return nil, err
+ }
+
+ if info.Type == RawTracepointType {
+ // Sadness upon sadness: a Tracing program with AttachRawTp returns
+ // a raw_tracepoint link. Other types return a tracing link.
+ return &rawTracepoint{raw}, nil
+ }
+
+ return &tracing{RawLink: RawLink{fd: fd}}, nil
+}
+
+// AttachTracing links a tracing (fentry/fexit/fmod_ret) BPF program or
+// a BTF-powered raw tracepoint (tp_btf) BPF Program to a BPF hook defined
+// in kernel modules.
+func AttachTracing(opts TracingOptions) (Link, error) {
+ if t := opts.Program.Type(); t != ebpf.Tracing {
+ return nil, fmt.Errorf("invalid program type %s, expected Tracing", t)
+ }
+
+ return attachBTFID(opts.Program)
+}
+
+// AttachLSM links a Linux security module (LSM) BPF Program to a BPF
+// hook defined in kernel modules.
+func AttachLSM(opts LSMOptions) (Link, error) {
+ if t := opts.Program.Type(); t != ebpf.LSM {
+ return nil, fmt.Errorf("invalid program type %s, expected LSM", t)
+ }
+
+ return attachBTFID(opts.Program)
+}