Move BLS related wrapper structure into a separate package (#3209)
Rongjian Lan
4 years ago
committed by
GitHub
parent
af38bc655d
commit
a168517dfc
@ -1,283 +1,89 @@ |
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package bls |
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|
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import ( |
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"bytes" |
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"encoding/hex" |
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"math/big" |
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|
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"github.com/harmony-one/bls/ffi/go/bls" |
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lru "github.com/hashicorp/golang-lru" |
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"github.com/pkg/errors" |
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) |
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const ( |
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blsPubKeyCacheSize = 1024 |
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) |
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var ( |
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// BLSPubKeyCache is the Cache of the Deserialized BLS PubKey
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BLSPubKeyCache, _ = lru.New(blsPubKeyCacheSize) |
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emptyBLSPubKey = SerializedPublicKey{} |
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) |
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func init() { |
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bls.Init(bls.BLS12_381) |
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} |
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// RandPrivateKey returns a random private key.
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func RandPrivateKey() *bls.SecretKey { |
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sec := bls.SecretKey{} |
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sec.SetByCSPRNG() |
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return &sec |
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} |
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var ( |
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errEmptyInput = errors.New("BytesToBLSPublicKey: empty input") |
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errPubKeyCast = errors.New("BytesToBLSPublicKey: cast error") |
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// PublicKeySizeInBytes ..
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const ( |
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PublicKeySizeInBytes = 48 |
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BLSSignatureSizeInBytes = 96 |
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) |
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// BytesToBLSPublicKey converts bytes into bls.PublicKey pointer.
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func BytesToBLSPublicKey(bytes []byte) (*bls.PublicKey, error) { |
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if len(bytes) == 0 { |
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return nil, errEmptyInput |
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} |
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kkey := string(bytes) |
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if k, ok := BLSPubKeyCache.Get(kkey); ok { |
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if pk, ok := k.(bls.PublicKey); ok { |
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return &pk, nil |
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} |
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return nil, errPubKeyCast |
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} |
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pubKey := &bls.PublicKey{} |
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err := pubKey.Deserialize(bytes) |
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if err == nil { |
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BLSPubKeyCache.Add(kkey, *pubKey) |
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return pubKey, nil |
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} |
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return nil, err |
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// PrivateKeyWrapper combines the bls private key and the corresponding public key
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type PrivateKeyWrapper struct { |
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Pri *bls.SecretKey |
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Pub *PublicKeyWrapper |
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} |
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// AggregateSig aggregates all the BLS signature into a single multi-signature.
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func AggregateSig(sigs []*bls.Sign) *bls.Sign { |
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var aggregatedSig bls.Sign |
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for _, sig := range sigs { |
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aggregatedSig.Add(sig) |
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} |
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return &aggregatedSig |
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// PublicKeyWrapper defines the bls public key in both serialized and
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// deserialized form.
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type PublicKeyWrapper struct { |
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Bytes SerializedPublicKey |
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Object *bls.PublicKey |
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} |
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// Mask represents a cosigning participation bitmask.
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type Mask struct { |
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Bitmap []byte |
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Publics []*bls.PublicKey |
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AggregatePublic *bls.PublicKey |
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} |
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// SerializedPublicKey defines the serialized bls public key
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type SerializedPublicKey [PublicKeySizeInBytes]byte |
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// NewMask returns a new participation bitmask for cosigning where all
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// cosigners are disabled by default. If a public key is given it verifies that
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// it is present in the list of keys and sets the corresponding index in the
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// bitmask to 1 (enabled).
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func NewMask(publics []*bls.PublicKey, myKey *bls.PublicKey) (*Mask, error) { |
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m := &Mask{ |
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Publics: publics, |
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} |
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m.Bitmap = make([]byte, m.Len()) |
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m.AggregatePublic = &bls.PublicKey{} |
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if myKey != nil { |
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found := false |
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for i, key := range publics { |
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if key.IsEqual(myKey) { |
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m.SetBit(i, true) |
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found = true |
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break |
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} |
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} |
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if !found { |
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return nil, errors.New("key not found") |
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} |
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} |
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return m, nil |
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} |
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// SerializedSignature defines the bls signature
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type SerializedSignature [BLSSignatureSizeInBytes]byte |
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// Clear clears the existing bits and aggregate public keys.
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func (m *Mask) Clear() { |
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m.Bitmap = make([]byte, m.Len()) |
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m.AggregatePublic = &bls.PublicKey{} |
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// Big ..
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func (pk SerializedPublicKey) Big() *big.Int { |
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return new(big.Int).SetBytes(pk[:]) |
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} |
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// Mask returns a copy of the participation bitmask.
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func (m *Mask) Mask() []byte { |
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clone := make([]byte, len(m.Bitmap)) |
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copy(clone[:], m.Bitmap) |
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return clone |
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// IsEmpty returns whether the bls public key is empty 0 bytes
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func (pk SerializedPublicKey) IsEmpty() bool { |
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return bytes.Equal(pk[:], emptyBLSPubKey[:]) |
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} |
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// Len returns the Bitmap length in bytes.
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func (m *Mask) Len() int { |
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return (len(m.Publics) + 7) >> 3 |
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// Hex returns the hex string of bls public key
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func (pk SerializedPublicKey) Hex() string { |
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return hex.EncodeToString(pk[:]) |
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} |
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// SetMask sets the participation bitmask according to the given byte slice
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// interpreted in little-endian order, i.e., bits 0-7 of byte 0 correspond to
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// cosigners 0-7, bits 0-7 of byte 1 correspond to cosigners 8-15, etc.
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func (m *Mask) SetMask(mask []byte) error { |
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if m.Len() != len(mask) { |
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return errors.Errorf( |
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"mismatching bitmap lengths expectedBitmapLength %d providedBitmapLength %d", |
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m.Len(), |
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len(mask), |
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) |
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} |
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for i := range m.Publics { |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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if ((m.Bitmap[byt] & msk) == 0) && ((mask[byt] & msk) != 0) { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 0 to 1
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m.AggregatePublic.Add(m.Publics[i]) |
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} |
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if ((m.Bitmap[byt] & msk) != 0) && ((mask[byt] & msk) == 0) { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 1 to 0
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m.AggregatePublic.Sub(m.Publics[i]) |
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} |
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} |
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return nil |
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// MarshalText so that we can use this as JSON printable when used as
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// key in a map
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func (pk SerializedPublicKey) MarshalText() (text []byte, err error) { |
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text = make([]byte, BLSSignatureSizeInBytes) |
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hex.Encode(text, pk[:]) |
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return text, nil |
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} |
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// SetBit enables (enable: true) or disables (enable: false) the bit
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// in the participation Bitmap of the given cosigner.
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func (m *Mask) SetBit(i int, enable bool) error { |
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if i >= len(m.Publics) { |
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return errors.New("index out of range") |
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} |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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if ((m.Bitmap[byt] & msk) == 0) && enable { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 0 to 1
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m.AggregatePublic.Add(m.Publics[i]) |
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} |
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if ((m.Bitmap[byt] & msk) != 0) && !enable { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 1 to 0
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m.AggregatePublic.Sub(m.Publics[i]) |
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} |
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// FromLibBLSPublicKeyUnsafe could give back nil, use only in cases when
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// have invariant that return value won't be nil
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func FromLibBLSPublicKeyUnsafe(key *bls.PublicKey) *SerializedPublicKey { |
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result := &SerializedPublicKey{} |
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if err := result.FromLibBLSPublicKey(key); err != nil { |
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return nil |
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} |
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// GetPubKeyFromMask will return pubkeys which masked either zero or one depending on the flag
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// it is used to show which signers are signed or not in the cosign message
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func (m *Mask) GetPubKeyFromMask(flag bool) []*bls.PublicKey { |
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pubKeys := []*bls.PublicKey{} |
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for i := range m.Publics { |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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if flag { |
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if (m.Bitmap[byt] & msk) != 0 { |
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pubKeys = append(pubKeys, m.Publics[i]) |
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} |
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} else { |
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if (m.Bitmap[byt] & msk) == 0 { |
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pubKeys = append(pubKeys, m.Publics[i]) |
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} |
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} |
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} |
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return pubKeys |
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} |
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// IndexEnabled checks whether the given index is enabled in the Bitmap or not.
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func (m *Mask) IndexEnabled(i int) (bool, error) { |
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if i >= len(m.Publics) { |
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return false, errors.New("index out of range") |
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} |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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return ((m.Bitmap[byt] & msk) != 0), nil |
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} |
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// KeyEnabled checks whether the index, corresponding to the given key, is
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// enabled in the Bitmap or not.
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func (m *Mask) KeyEnabled(public *bls.PublicKey) (bool, error) { |
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for i, key := range m.Publics { |
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if key.IsEqual(public) { |
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return m.IndexEnabled(i) |
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} |
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} |
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return false, errors.New("key not found") |
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return result |
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} |
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// SetKey set the bit in the Bitmap for the given cosigner
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func (m *Mask) SetKey(public *bls.PublicKey, enable bool) error { |
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for i, key := range m.Publics { |
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if key.IsEqual(public) { |
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return m.SetBit(i, enable) |
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} |
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} |
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return errors.New("key not found") |
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} |
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// CountEnabled returns the number of enabled nodes in the CoSi participation
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// Bitmap.
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func (m *Mask) CountEnabled() int { |
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// hw is hamming weight
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hw := 0 |
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for i := range m.Publics { |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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if (m.Bitmap[byt] & msk) != 0 { |
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hw++ |
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} |
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} |
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return hw |
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} |
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// CountTotal returns the total number of nodes this CoSi instance knows.
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func (m *Mask) CountTotal() int { |
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return len(m.Publics) |
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} |
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// AggregateMasks computes the bitwise OR of the two given participation masks.
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func AggregateMasks(a, b []byte) ([]byte, error) { |
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if len(a) != len(b) { |
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return nil, errors.New("mismatching Bitmap lengths") |
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} |
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m := make([]byte, len(a)) |
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for i := range m { |
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m[i] = a[i] | b[i] |
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// FromLibBLSPublicKey replaces the key contents with the given key,
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func (pk *SerializedPublicKey) FromLibBLSPublicKey(key *bls.PublicKey) error { |
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bytes := key.Serialize() |
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if len(bytes) != len(pk) { |
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return errors.Errorf( |
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"key size (BLS) size mismatch, expected %d have %d", len(pk), len(bytes), |
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) |
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} |
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return m, nil |
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} |
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// Policy represents a fully customizable cosigning policy deciding what
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// cosigner sets are and aren't sufficient for a collective signature to be
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// considered acceptable to a verifier. The Check method may inspect the set of
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// participants that cosigned by invoking cosi.Mask and/or cosi.MaskBit, and may
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// use any other relevant contextual information (e.g., how security-critical
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// the operation relying on the collective signature is) in determining whether
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// the collective signature was produced by an acceptable set of cosigners.
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type Policy interface { |
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Check(m *Mask) bool |
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} |
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// CompletePolicy is the default policy requiring that all participants have
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// cosigned to make a collective signature valid.
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type CompletePolicy struct { |
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} |
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// Check verifies that all participants have contributed to a collective
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// signature.
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func (p CompletePolicy) Check(m *Mask) bool { |
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return m.CountEnabled() == m.CountTotal() |
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} |
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// ThresholdPolicy allows to specify a simple t-of-n policy requring that at
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// least the given threshold number of participants t have cosigned to make a
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// collective signature valid.
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type ThresholdPolicy struct { |
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thold int |
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} |
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// NewThresholdPolicy returns a new ThresholdPolicy with the given threshold.
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func NewThresholdPolicy(thold int) *ThresholdPolicy { |
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return &ThresholdPolicy{thold: thold} |
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copy(pk[:], bytes) |
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return nil |
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} |
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// Check verifies that at least a threshold number of participants have
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// contributed to a collective signature.
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func (p ThresholdPolicy) Check(m *Mask) bool { |
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return m.CountEnabled() >= p.thold |
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// ToLibBLSPublicKey copies the key contents into the given key.
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func (pk *SerializedPublicKey) ToLibBLSPublicKey(key *bls.PublicKey) error { |
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return key.Deserialize(pk[:]) |
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} |
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@ -0,0 +1,283 @@ |
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package bls |
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import ( |
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"github.com/harmony-one/bls/ffi/go/bls" |
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lru "github.com/hashicorp/golang-lru" |
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"github.com/pkg/errors" |
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) |
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const ( |
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blsPubKeyCacheSize = 1024 |
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) |
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var ( |
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// BLSPubKeyCache is the Cache of the Deserialized BLS PubKey
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BLSPubKeyCache, _ = lru.New(blsPubKeyCacheSize) |
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) |
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func init() { |
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bls.Init(bls.BLS12_381) |
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} |
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// RandPrivateKey returns a random private key.
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func RandPrivateKey() *bls.SecretKey { |
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sec := bls.SecretKey{} |
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sec.SetByCSPRNG() |
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return &sec |
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} |
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var ( |
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errEmptyInput = errors.New("BytesToBLSPublicKey: empty input") |
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errPubKeyCast = errors.New("BytesToBLSPublicKey: cast error") |
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) |
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// BytesToBLSPublicKey converts bytes into bls.PublicKey pointer.
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func BytesToBLSPublicKey(bytes []byte) (*bls.PublicKey, error) { |
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if len(bytes) == 0 { |
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return nil, errEmptyInput |
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} |
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kkey := string(bytes) |
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if k, ok := BLSPubKeyCache.Get(kkey); ok { |
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if pk, ok := k.(bls.PublicKey); ok { |
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return &pk, nil |
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} |
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return nil, errPubKeyCast |
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} |
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pubKey := &bls.PublicKey{} |
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err := pubKey.Deserialize(bytes) |
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if err == nil { |
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BLSPubKeyCache.Add(kkey, *pubKey) |
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return pubKey, nil |
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} |
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return nil, err |
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} |
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// AggregateSig aggregates all the BLS signature into a single multi-signature.
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func AggregateSig(sigs []*bls.Sign) *bls.Sign { |
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var aggregatedSig bls.Sign |
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for _, sig := range sigs { |
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aggregatedSig.Add(sig) |
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} |
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return &aggregatedSig |
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} |
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// Mask represents a cosigning participation bitmask.
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type Mask struct { |
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Bitmap []byte |
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Publics []*bls.PublicKey |
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AggregatePublic *bls.PublicKey |
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} |
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// NewMask returns a new participation bitmask for cosigning where all
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// cosigners are disabled by default. If a public key is given it verifies that
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// it is present in the list of keys and sets the corresponding index in the
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// bitmask to 1 (enabled).
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func NewMask(publics []*bls.PublicKey, myKey *bls.PublicKey) (*Mask, error) { |
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m := &Mask{ |
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Publics: publics, |
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} |
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m.Bitmap = make([]byte, m.Len()) |
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m.AggregatePublic = &bls.PublicKey{} |
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if myKey != nil { |
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found := false |
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for i, key := range publics { |
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if key.IsEqual(myKey) { |
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m.SetBit(i, true) |
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found = true |
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break |
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} |
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} |
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if !found { |
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return nil, errors.New("key not found") |
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} |
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} |
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return m, nil |
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} |
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// Clear clears the existing bits and aggregate public keys.
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func (m *Mask) Clear() { |
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m.Bitmap = make([]byte, m.Len()) |
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m.AggregatePublic = &bls.PublicKey{} |
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} |
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// Mask returns a copy of the participation bitmask.
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func (m *Mask) Mask() []byte { |
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clone := make([]byte, len(m.Bitmap)) |
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copy(clone[:], m.Bitmap) |
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return clone |
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} |
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// Len returns the Bitmap length in bytes.
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func (m *Mask) Len() int { |
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return (len(m.Publics) + 7) >> 3 |
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} |
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// SetMask sets the participation bitmask according to the given byte slice
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// interpreted in little-endian order, i.e., bits 0-7 of byte 0 correspond to
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// cosigners 0-7, bits 0-7 of byte 1 correspond to cosigners 8-15, etc.
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func (m *Mask) SetMask(mask []byte) error { |
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if m.Len() != len(mask) { |
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return errors.Errorf( |
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"mismatching bitmap lengths expectedBitmapLength %d providedBitmapLength %d", |
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m.Len(), |
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len(mask), |
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) |
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} |
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for i := range m.Publics { |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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if ((m.Bitmap[byt] & msk) == 0) && ((mask[byt] & msk) != 0) { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 0 to 1
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m.AggregatePublic.Add(m.Publics[i]) |
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} |
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if ((m.Bitmap[byt] & msk) != 0) && ((mask[byt] & msk) == 0) { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 1 to 0
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m.AggregatePublic.Sub(m.Publics[i]) |
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} |
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} |
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return nil |
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} |
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// SetBit enables (enable: true) or disables (enable: false) the bit
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// in the participation Bitmap of the given cosigner.
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func (m *Mask) SetBit(i int, enable bool) error { |
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if i >= len(m.Publics) { |
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return errors.New("index out of range") |
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} |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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if ((m.Bitmap[byt] & msk) == 0) && enable { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 0 to 1
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m.AggregatePublic.Add(m.Publics[i]) |
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} |
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if ((m.Bitmap[byt] & msk) != 0) && !enable { |
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m.Bitmap[byt] ^= msk // flip bit in Bitmap from 1 to 0
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m.AggregatePublic.Sub(m.Publics[i]) |
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} |
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return nil |
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} |
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|
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// GetPubKeyFromMask will return pubkeys which masked either zero or one depending on the flag
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// it is used to show which signers are signed or not in the cosign message
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func (m *Mask) GetPubKeyFromMask(flag bool) []*bls.PublicKey { |
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pubKeys := []*bls.PublicKey{} |
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for i := range m.Publics { |
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byt := i >> 3 |
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msk := byte(1) << uint(i&7) |
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if flag { |
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if (m.Bitmap[byt] & msk) != 0 { |
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pubKeys = append(pubKeys, m.Publics[i]) |
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} |
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} else { |
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if (m.Bitmap[byt] & msk) == 0 { |
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pubKeys = append(pubKeys, m.Publics[i]) |
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} |
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} |
||||
} |
||||
return pubKeys |
||||
} |
||||
|
||||
// IndexEnabled checks whether the given index is enabled in the Bitmap or not.
|
||||
func (m *Mask) IndexEnabled(i int) (bool, error) { |
||||
if i >= len(m.Publics) { |
||||
return false, errors.New("index out of range") |
||||
} |
||||
byt := i >> 3 |
||||
msk := byte(1) << uint(i&7) |
||||
return ((m.Bitmap[byt] & msk) != 0), nil |
||||
} |
||||
|
||||
// KeyEnabled checks whether the index, corresponding to the given key, is
|
||||
// enabled in the Bitmap or not.
|
||||
func (m *Mask) KeyEnabled(public *bls.PublicKey) (bool, error) { |
||||
for i, key := range m.Publics { |
||||
if key.IsEqual(public) { |
||||
return m.IndexEnabled(i) |
||||
} |
||||
} |
||||
return false, errors.New("key not found") |
||||
} |
||||
|
||||
// SetKey set the bit in the Bitmap for the given cosigner
|
||||
func (m *Mask) SetKey(public *bls.PublicKey, enable bool) error { |
||||
for i, key := range m.Publics { |
||||
if key.IsEqual(public) { |
||||
return m.SetBit(i, enable) |
||||
} |
||||
} |
||||
return errors.New("key not found") |
||||
} |
||||
|
||||
// CountEnabled returns the number of enabled nodes in the CoSi participation
|
||||
// Bitmap.
|
||||
func (m *Mask) CountEnabled() int { |
||||
// hw is hamming weight
|
||||
hw := 0 |
||||
for i := range m.Publics { |
||||
byt := i >> 3 |
||||
msk := byte(1) << uint(i&7) |
||||
if (m.Bitmap[byt] & msk) != 0 { |
||||
hw++ |
||||
} |
||||
} |
||||
return hw |
||||
} |
||||
|
||||
// CountTotal returns the total number of nodes this CoSi instance knows.
|
||||
func (m *Mask) CountTotal() int { |
||||
return len(m.Publics) |
||||
} |
||||
|
||||
// AggregateMasks computes the bitwise OR of the two given participation masks.
|
||||
func AggregateMasks(a, b []byte) ([]byte, error) { |
||||
if len(a) != len(b) { |
||||
return nil, errors.New("mismatching Bitmap lengths") |
||||
} |
||||
m := make([]byte, len(a)) |
||||
for i := range m { |
||||
m[i] = a[i] | b[i] |
||||
} |
||||
return m, nil |
||||
} |
||||
|
||||
// Policy represents a fully customizable cosigning policy deciding what
|
||||
// cosigner sets are and aren't sufficient for a collective signature to be
|
||||
// considered acceptable to a verifier. The Check method may inspect the set of
|
||||
// participants that cosigned by invoking cosi.Mask and/or cosi.MaskBit, and may
|
||||
// use any other relevant contextual information (e.g., how security-critical
|
||||
// the operation relying on the collective signature is) in determining whether
|
||||
// the collective signature was produced by an acceptable set of cosigners.
|
||||
type Policy interface { |
||||
Check(m *Mask) bool |
||||
} |
||||
|
||||
// CompletePolicy is the default policy requiring that all participants have
|
||||
// cosigned to make a collective signature valid.
|
||||
type CompletePolicy struct { |
||||
} |
||||
|
||||
// Check verifies that all participants have contributed to a collective
|
||||
// signature.
|
||||
func (p CompletePolicy) Check(m *Mask) bool { |
||||
return m.CountEnabled() == m.CountTotal() |
||||
} |
||||
|
||||
// ThresholdPolicy allows to specify a simple t-of-n policy requring that at
|
||||
// least the given threshold number of participants t have cosigned to make a
|
||||
// collective signature valid.
|
||||
type ThresholdPolicy struct { |
||||
thold int |
||||
} |
||||
|
||||
// NewThresholdPolicy returns a new ThresholdPolicy with the given threshold.
|
||||
func NewThresholdPolicy(thold int) *ThresholdPolicy { |
||||
return &ThresholdPolicy{thold: thold} |
||||
} |
||||
|
||||
// Check verifies that at least a threshold number of participants have
|
||||
// contributed to a collective signature.
|
||||
func (p ThresholdPolicy) Check(m *Mask) bool { |
||||
return m.CountEnabled() >= p.thold |
||||
} |
||||
Loading…
Reference in new issue