Merge pull request #201 from Bytom/v0.1

[bytom/vapor.git] / vendor / github.com / bytom / protocol / vm / vmutil / script.go

diff --git a/vendor/github.com/bytom/protocol/vm/vmutil/script.go b/vendor/github.com/bytom/protocol/vm/vmutil/script.go
new file mode 100644 (file)
index 0000000..7cef891
--- /dev/null
+++ b/vendor/github.com/bytom/protocol/vm/vmutil/script.go
@@ -0,0 +1,154 @@
+package vmutil
+
+import (
+       "github.com/bytom/crypto/ed25519"
+       "github.com/bytom/errors"
+       "github.com/bytom/protocol/vm"
+)
+
+// pre-define errors
+var (
+       ErrBadValue       = errors.New("bad value")
+       ErrMultisigFormat = errors.New("bad multisig program format")
+)
+
+// IsUnspendable checks if a contorl program is absolute failed
+func IsUnspendable(prog []byte) bool {
+       return len(prog) > 0 && prog[0] == byte(vm.OP_FAIL)
+}
+
+func (b *Builder) addP2SPMultiSig(pubkeys []ed25519.PublicKey, nrequired int) error {
+       if err := checkMultiSigParams(int64(nrequired), int64(len(pubkeys))); err != nil {
+               return err
+       }
+
+       b.AddOp(vm.OP_TXSIGHASH) // stack is now [... NARGS SIG SIG SIG PREDICATEHASH]
+       for _, p := range pubkeys {
+               b.AddData(p)
+       }
+       b.AddInt64(int64(nrequired))    // stack is now [... SIG SIG SIG PREDICATEHASH PUB PUB PUB M]
+       b.AddInt64(int64(len(pubkeys))) // stack is now [... SIG SIG SIG PREDICATEHASH PUB PUB PUB M N]
+       b.AddOp(vm.OP_CHECKMULTISIG)    // stack is now [... NARGS]
+       return nil
+}
+
+// DefaultCoinbaseProgram generates the script for contorl coinbase output
+func DefaultCoinbaseProgram() ([]byte, error) {
+       builder := NewBuilder()
+       builder.AddOp(vm.OP_TRUE)
+       return builder.Build()
+}
+
+// P2WPKHProgram return the segwit pay to public key hash
+func P2WPKHProgram(hash []byte) ([]byte, error) {
+       builder := NewBuilder()
+       builder.AddInt64(0)
+       builder.AddData(hash)
+       return builder.Build()
+}
+
+// P2WSHProgram return the segwit pay to script hash
+func P2WSHProgram(hash []byte) ([]byte, error) {
+       builder := NewBuilder()
+       builder.AddInt64(0)
+       builder.AddData(hash)
+       return builder.Build()
+}
+
+// RetireProgram generates the script for retire output
+func RetireProgram(comment []byte) ([]byte, error) {
+       builder := NewBuilder()
+       builder.AddOp(vm.OP_FAIL)
+       if len(comment) != 0 {
+               builder.AddData(comment)
+       }
+       return builder.Build()
+}
+
+// P2PKHSigProgram generates the script for control with pubkey hash
+func P2PKHSigProgram(pubkeyHash []byte) ([]byte, error) {
+       builder := NewBuilder()
+       builder.AddOp(vm.OP_DUP)
+       builder.AddOp(vm.OP_HASH160)
+       builder.AddData(pubkeyHash)
+       builder.AddOp(vm.OP_EQUALVERIFY)
+       builder.AddOp(vm.OP_TXSIGHASH)
+       builder.AddOp(vm.OP_SWAP)
+       builder.AddOp(vm.OP_CHECKSIG)
+       return builder.Build()
+}
+
+// P2SHProgram generates the script for control with script hash
+func P2SHProgram(scriptHash []byte) ([]byte, error) {
+       builder := NewBuilder()
+       builder.AddOp(vm.OP_DUP)
+       builder.AddOp(vm.OP_SHA3)
+       builder.AddData(scriptHash)
+       builder.AddOp(vm.OP_EQUALVERIFY)
+       builder.AddInt64(-1)
+       builder.AddOp(vm.OP_SWAP)
+       builder.AddInt64(0)
+       builder.AddOp(vm.OP_CHECKPREDICATE)
+       return builder.Build()
+}
+
+// P2SPMultiSigProgram generates the script for control transaction output
+func P2SPMultiSigProgram(pubkeys []ed25519.PublicKey, nrequired int) ([]byte, error) {
+       builder := NewBuilder()
+       if err := builder.addP2SPMultiSig(pubkeys, nrequired); err != nil {
+               return nil, err
+       }
+       return builder.Build()
+}
+
+// P2SPMultiSigProgramWithHeight generates the script with block height for control transaction output
+func P2SPMultiSigProgramWithHeight(pubkeys []ed25519.PublicKey, nrequired int, blockHeight int64) ([]byte, error) {
+       builder := NewBuilder()
+       if blockHeight > 0 {
+               builder.AddInt64(blockHeight)
+               builder.AddOp(vm.OP_BLOCKHEIGHT)
+               builder.AddOp(vm.OP_GREATERTHAN)
+               builder.AddOp(vm.OP_VERIFY)
+       } else if blockHeight < 0 {
+               return nil, errors.WithDetail(ErrBadValue, "negative blockHeight")
+       }
+       if err := builder.addP2SPMultiSig(pubkeys, nrequired); err != nil {
+               return nil, err
+       }
+       return builder.Build()
+}
+
+func checkMultiSigParams(nrequired, npubkeys int64) error {
+       if nrequired < 0 {
+               return errors.WithDetail(ErrBadValue, "negative quorum")
+       }
+       if npubkeys < 0 {
+               return errors.WithDetail(ErrBadValue, "negative pubkey count")
+       }
+       if nrequired > npubkeys {
+               return errors.WithDetail(ErrBadValue, "quorum too big")
+       }
+       if nrequired == 0 && npubkeys > 0 {
+               return errors.WithDetail(ErrBadValue, "quorum empty with non-empty pubkey list")
+       }
+       return nil
+}
+
+// GetIssuanceProgramRestrictHeight return issuance program restrict height
+// if height invalid return 0
+func GetIssuanceProgramRestrictHeight(program []byte) int64 {
+       insts, err := vm.ParseProgram(program)
+       if err != nil {
+               return 0
+       }
+
+       if len(insts) >= 4 && insts[0].IsPushdata() && insts[1].Op == vm.OP_BLOCKHEIGHT && insts[2].Op == vm.OP_GREATERTHAN && insts[3].Op == vm.OP_VERIFY {
+               height, err := vm.AsInt64(insts[0].Data)
+               if err != nil {
+                       return 0
+               }
+
+               return height
+       }
+       return 0
+}