flip/dcrd
1
0
Fork 0
mirror of https://github.com/FlipsideCrypto/dcrd.git synced 2026-02-06 10:56:47 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
master
dcrd/txscript/error_test.go

168 lines
5.2 KiB
Go
Raw Permalink Normal View History

txscript: Significantly improve errors. This converts the majority of script errors from generic errors created via errors.New and fmt.Errorf to use a concrete type that implements the error interface with an error code and description. This allows callers to programmatically detect the type of error via type assertions and an error code while still allowing the errors to provide more context. For example, instead of just having an error the reads "disabled opcode" as would happen prior to these changes when a disabled opcode is encountered, the error will now read "attempt to execute disabled opcode OP_FOO". While it was previously possible to programmatically detect many errors due to them being exported, they provided no additional context and there were also various instances that were just returning errors created on the spot which callers could not reliably detect without resorting to looking at the actual error message, which is nearly always bad practice. Also, while here, export the MaxStackSize and MaxScriptSize constants since they can be useful for consumers of the package and perform some minor cleanup of some of the tests.
2018-06-29 16:58:31 +00:00
// Copyright (c) 2017 The btcsuite developers
txscript: Introduce zero-alloc script tokenizer. This implements an efficient and zero-allocation script tokenizer that is exported to both provide a new capability to tokenize scripts to external consumers of the API as well as to serve as a base for refactoring the existing highly inefficient internal code. It is important to note that this tokenizer is intended to be used in consensus critical code in the future, so it must exactly follow the existing semantics. The current script parsing mechanism used throughout the txscript module is to fully tokenize the scripts into an array of internal parsed opcodes which are then examined and passed around in order to implement virtually everything related to scripts. While that approach does simplify the analysis of certain scripts and thus provide some nice properties in that regard, it is both extremely inefficient in many cases, and makes it impossible for external consumers of the API to implement any form of custom script analysis without manually implementing a bunch of error prone tokenizing code or, alternatively, the script engine exposing internal structures. For example, as shown by profiling the total memory allocations of an initial sync, the existing script parsing code allocates a total of around 295.12GB, which equates to around 50% of all allocations performed. The zero-alloc tokenizer this introduces will allow that to be reduced to virtually zero. The following is a before and after comparison of tokenizing a large script with a high opcode count using the existing code versus the tokenizer this introduces for both speed and memory allocations: benchmark old ns/op new ns/op delta ------------------------------------------------------------ BenchmarkScriptParsing 153099 961 -99.37% benchmark old allocs new allocs delta ------------------------------------------------------------ BenchmarkScriptParsing 1 0 -100.00% benchmark old bytes new bytes delta ------------------------------------------------------------ BenchmarkScriptParsing 466945 0 -100.00% The following is an overview of the changes: - Introduce new error code ErrUnsupportedScriptVersion - Implement zero-allocation script tokenizer - Add a full suite of tests to ensure the tokenizer works as intended and follows the required consensus semantics - Add an example of using the new tokenizer to count the number of opcodes in a script - Update README.md to include the new example - Update script parsing benchmark to use the new tokenizer
2019-03-13 06:11:03 +00:00
// Copyright (c) 2015-2019 The Decred developers
txscript: Significantly improve errors. This converts the majority of script errors from generic errors created via errors.New and fmt.Errorf to use a concrete type that implements the error interface with an error code and description. This allows callers to programmatically detect the type of error via type assertions and an error code while still allowing the errors to provide more context. For example, instead of just having an error the reads "disabled opcode" as would happen prior to these changes when a disabled opcode is encountered, the error will now read "attempt to execute disabled opcode OP_FOO". While it was previously possible to programmatically detect many errors due to them being exported, they provided no additional context and there were also various instances that were just returning errors created on the spot which callers could not reliably detect without resorting to looking at the actual error message, which is nearly always bad practice. Also, while here, export the MaxStackSize and MaxScriptSize constants since they can be useful for consumers of the package and perform some minor cleanup of some of the tests.
2018-06-29 16:58:31 +00:00
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package txscript
import (
"testing"
)
// TestErrorCodeStringer tests the stringized output for the ErrorCode type.
func TestErrorCodeStringer(t *testing.T) {
t.Parallel()
tests := []struct {
in ErrorCode
want string
}{
{ErrInternal, "ErrInternal"},
{ErrInvalidIndex, "ErrInvalidIndex"},
{ErrInvalidSigHashSingleIndex, "ErrInvalidSigHashSingleIndex"},
{ErrUnsupportedAddress, "ErrUnsupportedAddress"},
{ErrTooManyRequiredSigs, "ErrTooManyRequiredSigs"},
{ErrMalformedCoinbaseNullData, "ErrMalformedCoinbaseNullData"},
{ErrTooMuchNullData, "ErrTooMuchNullData"},
txscript: Introduce zero-alloc script tokenizer. This implements an efficient and zero-allocation script tokenizer that is exported to both provide a new capability to tokenize scripts to external consumers of the API as well as to serve as a base for refactoring the existing highly inefficient internal code. It is important to note that this tokenizer is intended to be used in consensus critical code in the future, so it must exactly follow the existing semantics. The current script parsing mechanism used throughout the txscript module is to fully tokenize the scripts into an array of internal parsed opcodes which are then examined and passed around in order to implement virtually everything related to scripts. While that approach does simplify the analysis of certain scripts and thus provide some nice properties in that regard, it is both extremely inefficient in many cases, and makes it impossible for external consumers of the API to implement any form of custom script analysis without manually implementing a bunch of error prone tokenizing code or, alternatively, the script engine exposing internal structures. For example, as shown by profiling the total memory allocations of an initial sync, the existing script parsing code allocates a total of around 295.12GB, which equates to around 50% of all allocations performed. The zero-alloc tokenizer this introduces will allow that to be reduced to virtually zero. The following is a before and after comparison of tokenizing a large script with a high opcode count using the existing code versus the tokenizer this introduces for both speed and memory allocations: benchmark old ns/op new ns/op delta ------------------------------------------------------------ BenchmarkScriptParsing 153099 961 -99.37% benchmark old allocs new allocs delta ------------------------------------------------------------ BenchmarkScriptParsing 1 0 -100.00% benchmark old bytes new bytes delta ------------------------------------------------------------ BenchmarkScriptParsing 466945 0 -100.00% The following is an overview of the changes: - Introduce new error code ErrUnsupportedScriptVersion - Implement zero-allocation script tokenizer - Add a full suite of tests to ensure the tokenizer works as intended and follows the required consensus semantics - Add an example of using the new tokenizer to count the number of opcodes in a script - Update README.md to include the new example - Update script parsing benchmark to use the new tokenizer
2019-03-13 06:11:03 +00:00
{ErrUnsupportedScriptVersion, "ErrUnsupportedScriptVersion"},
txscript: Significantly improve errors. This converts the majority of script errors from generic errors created via errors.New and fmt.Errorf to use a concrete type that implements the error interface with an error code and description. This allows callers to programmatically detect the type of error via type assertions and an error code while still allowing the errors to provide more context. For example, instead of just having an error the reads "disabled opcode" as would happen prior to these changes when a disabled opcode is encountered, the error will now read "attempt to execute disabled opcode OP_FOO". While it was previously possible to programmatically detect many errors due to them being exported, they provided no additional context and there were also various instances that were just returning errors created on the spot which callers could not reliably detect without resorting to looking at the actual error message, which is nearly always bad practice. Also, while here, export the MaxStackSize and MaxScriptSize constants since they can be useful for consumers of the package and perform some minor cleanup of some of the tests.
2018-06-29 16:58:31 +00:00
{ErrNotMultisigScript, "ErrNotMultisigScript"},
{ErrEarlyReturn, "ErrEarlyReturn"},
{ErrEmptyStack, "ErrEmptyStack"},
{ErrEvalFalse, "ErrEvalFalse"},
{ErrScriptUnfinished, "ErrScriptUnfinished"},
{ErrInvalidProgramCounter, "ErrInvalidProgramCounter"},
{ErrScriptTooBig, "ErrScriptTooBig"},
{ErrElementTooBig, "ErrElementTooBig"},
{ErrTooManyOperations, "ErrTooManyOperations"},
{ErrStackOverflow, "ErrStackOverflow"},
{ErrInvalidPubKeyCount, "ErrInvalidPubKeyCount"},
{ErrInvalidSignatureCount, "ErrInvalidSignatureCount"},
{ErrNumOutOfRange, "ErrNumOutOfRange"},
{ErrVerify, "ErrVerify"},
{ErrEqualVerify, "ErrEqualVerify"},
{ErrNumEqualVerify, "ErrNumEqualVerify"},
{ErrCheckSigVerify, "ErrCheckSigVerify"},
{ErrCheckMultiSigVerify, "ErrCheckMultiSigVerify"},
txscript: Consistent checksigaltverify handling. This introduces a new error named ErrCheckSigAltVerify and modifies the opcodeCheckSigAltVerify handler to use the abstractVerify function along with the new error. This makes the handling consistent with all other signature checking verification opcode handlers and ensures the error both can be programmatically detected as well as be uniquely identified as compared to a generic verify failure.
2019-03-08 01:40:49 +00:00
{ErrCheckSigAltVerify, "ErrCheckSigAltVerify"},
txscript: Significantly improve errors. This converts the majority of script errors from generic errors created via errors.New and fmt.Errorf to use a concrete type that implements the error interface with an error code and description. This allows callers to programmatically detect the type of error via type assertions and an error code while still allowing the errors to provide more context. For example, instead of just having an error the reads "disabled opcode" as would happen prior to these changes when a disabled opcode is encountered, the error will now read "attempt to execute disabled opcode OP_FOO". While it was previously possible to programmatically detect many errors due to them being exported, they provided no additional context and there were also various instances that were just returning errors created on the spot which callers could not reliably detect without resorting to looking at the actual error message, which is nearly always bad practice. Also, while here, export the MaxStackSize and MaxScriptSize constants since they can be useful for consumers of the package and perform some minor cleanup of some of the tests.
2018-06-29 16:58:31 +00:00
{ErrP2SHStakeOpCodes, "ErrP2SHStakeOpCodes"},
{ErrDisabledOpcode, "ErrDisabledOpcode"},
{ErrReservedOpcode, "ErrReservedOpcode"},
{ErrMalformedPush, "ErrMalformedPush"},
{ErrInvalidStackOperation, "ErrInvalidStackOperation"},
{ErrUnbalancedConditional, "ErrUnbalancedConditional"},
{ErrNegativeSubstrIdx, "ErrNegativeSubstrIdx"},
{ErrOverflowSubstrIdx, "ErrOverflowSubstrIdx"},
{ErrNegativeRotation, "ErrNegativeRotation"},
{ErrOverflowRotation, "ErrOverflowRotation"},
{ErrDivideByZero, "ErrDivideByZero"},
{ErrNegativeShift, "ErrNegativeShift"},
{ErrOverflowShift, "ErrOverflowShift"},
{ErrMinimalData, "ErrMinimalData"},
{ErrInvalidSigHashType, "ErrInvalidSigHashType"},
{ErrSigTooShort, "ErrSigTooShort"},
{ErrSigTooLong, "ErrSigTooLong"},
{ErrSigInvalidSeqID, "ErrSigInvalidSeqID"},
{ErrSigInvalidDataLen, "ErrSigInvalidDataLen"},
{ErrSigMissingSTypeID, "ErrSigMissingSTypeID"},
{ErrSigMissingSLen, "ErrSigMissingSLen"},
{ErrSigInvalidSLen, "ErrSigInvalidSLen"},
{ErrSigInvalidRIntID, "ErrSigInvalidRIntID"},
{ErrSigZeroRLen, "ErrSigZeroRLen"},
{ErrSigNegativeR, "ErrSigNegativeR"},
{ErrSigTooMuchRPadding, "ErrSigTooMuchRPadding"},
{ErrSigInvalidSIntID, "ErrSigInvalidSIntID"},
{ErrSigZeroSLen, "ErrSigZeroSLen"},
{ErrSigNegativeS, "ErrSigNegativeS"},
{ErrSigTooMuchSPadding, "ErrSigTooMuchSPadding"},
{ErrSigHighS, "ErrSigHighS"},
{ErrNotPushOnly, "ErrNotPushOnly"},
{ErrPubKeyType, "ErrPubKeyType"},
{ErrCleanStack, "ErrCleanStack"},
{ErrDiscourageUpgradableNOPs, "ErrDiscourageUpgradableNOPs"},
{ErrNegativeLockTime, "ErrNegativeLockTime"},
{ErrUnsatisfiedLockTime, "ErrUnsatisfiedLockTime"},
{0xffff, "Unknown ErrorCode (65535)"},
}
// Detect additional error codes that don't have the stringer added.
if len(tests)-1 != int(numErrorCodes) {
t.Errorf("It appears an error code was added without adding an " +
"associated stringer test")
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
result := test.in.String()
if result != test.want {
t.Errorf("String #%d\n got: %s want: %s", i, result,
test.want)
continue
}
}
}
// TestError tests the error output for the Error type.
func TestError(t *testing.T) {
t.Parallel()
tests := []struct {
in Error
want string
}{
{
Error{Description: "some error"},
"some error",
},
{
Error{Description: "human-readable error"},
"human-readable error",
},
}
t.Logf("Running %d tests", len(tests))
for i, test := range tests {
result := test.in.Error()
if result != test.want {
t.Errorf("Error #%d\n got: %s want: %s", i, result,
test.want)
continue
}
}
}
// TestIsDERSigError ensures IsDERSigError returns true for all error codes
// that can be returned as a result of non-canonically-encoded DER signatures.
func TestIsDERSigError(t *testing.T) {
tests := []struct {
code ErrorCode
want bool
}{
{ErrSigTooShort, true},
{ErrSigTooLong, true},
{ErrSigInvalidSeqID, true},
{ErrSigInvalidDataLen, true},
{ErrSigMissingSTypeID, true},
{ErrSigMissingSLen, true},
{ErrSigInvalidSLen, true},
{ErrSigInvalidRIntID, true},
{ErrSigZeroRLen, true},
{ErrSigNegativeR, true},
{ErrSigTooMuchRPadding, true},
{ErrSigInvalidSIntID, true},
{ErrSigZeroSLen, true},
{ErrSigNegativeS, true},
{ErrSigTooMuchSPadding, true},
{ErrSigHighS, true},
{ErrEvalFalse, false},
{ErrInvalidIndex, false},
}
for _, test := range tests {
result := IsDERSigError(Error{ErrorCode: test.code})
if result != test.want {
t.Errorf("IsDERSigError(%v): unexpected result -- got: %v want: %v",
test.code, result, test.want)
continue
}
}
}
Reference in New Issue Copy Permalink