Add Nix flake for mciasctl and mciasgrpcctl

Vendor dependencies and expose control program binaries via
nix build. Uses nixpkgs-unstable for Go 1.26 support.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

vendor/github.com/google/go-tpm/tpm2/names.go

@@ -0,0 +1,62 @@
+package tpm2
+
+import (
+	"bytes"
+	"encoding/binary"
+	"reflect"
+)
+
+// HandleName returns the TPM Name of a PCR, session, or permanent value
+// (e.g., hierarchy) handle.
+func HandleName(h TPMHandle) TPM2BName {
+	result := make([]byte, 4)
+	binary.BigEndian.PutUint32(result, uint32(h))
+	return TPM2BName{
+		Buffer: result,
+	}
+}
+
+// objectOrNVName calculates the Name of an NV index or object.
+// pub is a pointer to either a TPMTPublic or TPMSNVPublic.
+func objectOrNVName(alg TPMAlgID, pub interface{}) (*TPM2BName, error) {
+	h, err := alg.Hash()
+	if err != nil {
+		return nil, err
+	}
+
+	// Create a byte slice with the correct reserved size and marshal the
+	// NameAlg to it.
+	result := make([]byte, 2, 2+h.Size())
+	binary.BigEndian.PutUint16(result, uint16(alg))
+
+	// Calculate the hash of the entire Public contents and append it to the
+	// result.
+	ha := h.New()
+	var buf bytes.Buffer
+	if err := marshal(&buf, reflect.ValueOf(pub)); err != nil {
+		return nil, err
+	}
+	ha.Write(buf.Bytes())
+	result = ha.Sum(result)
+
+	return &TPM2BName{
+		Buffer: result,
+	}, nil
+}
+
+// ObjectName returns the TPM Name of an object.
+func ObjectName(p *TPMTPublic) (*TPM2BName, error) {
+	return objectOrNVName(p.NameAlg, p)
+}
+
+// NVName returns the TPM Name of an NV index.
+func NVName(p *TPMSNVPublic) (*TPM2BName, error) {
+	return objectOrNVName(p.NameAlg, p)
+}
+
+// PrimaryHandleName returns the TPM Name of a primary handle.
+func PrimaryHandleName(h TPMHandle) []byte {
+	result := make([]byte, 4)
+	binary.BigEndian.PutUint32(result, uint32(h))
+	return result
+}