package smartcontract import ( "bytes" "fmt" "sort" "github.com/CityOfZion/neo-go/pkg/crypto/keys" "github.com/CityOfZion/neo-go/pkg/vm" "github.com/CityOfZion/neo-go/pkg/vm/opcode" ) // CreateMultiSigRedeemScript creates a script runnable by the VM. func CreateMultiSigRedeemScript(m int, publicKeys keys.PublicKeys) ([]byte, error) { if m < 1 { return nil, fmt.Errorf("param m cannot be smaller or equal to 1 got %d", m) } if m > len(publicKeys) { return nil, fmt.Errorf("length of the signatures (%d) is higher then the number of public keys", m) } if m > 1024 { return nil, fmt.Errorf("public key count %d exceeds maximum of length 1024", len(publicKeys)) } buf := new(bytes.Buffer) if err := vm.EmitInt(buf, int64(m)); err != nil { return nil, err } sort.Sort(publicKeys) for _, pubKey := range publicKeys { if err := vm.EmitBytes(buf, pubKey.Bytes()); err != nil { return nil, err } } if err := vm.EmitInt(buf, int64(len(publicKeys))); err != nil { return nil, err } if err := vm.EmitOpcode(buf, opcode.CHECKMULTISIG); err != nil { return nil, err } return buf.Bytes(), nil }