Add scanner/valuer interface to signature

babyjub/eddsa.go

@@ -2,6 +2,8 @@ package babyjub
 
 import (
 	"crypto/rand"
+	"database/sql/driver"
+	"fmt"
 
 	"github.com/iden3/go-iden3-crypto/mimc7"
 	"github.com/iden3/go-iden3-crypto/poseidon"
@@ -175,6 +177,27 @@ func (s *SignatureComp) Decompress() (*Signature, error) {
 	return new(Signature).Decompress(*s)
 }
 
+// Scan implements Scanner for database/sql.
+func (s *Signature) Scan(src interface{}) error {
+	srcB, ok := src.([]byte)
+	if !ok {
+		return fmt.Errorf("can't scan %T into Signature", src)
+	}
+	if len(srcB) != 64 {
+		return fmt.Errorf("can't scan []byte of len %d into Signature, want %d", len(srcB), 64)
+	}
+	buf := [64]byte{}
+	copy(buf[:], srcB[:])
+	_, err := s.Decompress(buf)
+	return err
+}
+
+// Value implements valuer for database/sql.
+func (s *Signature) Value() (driver.Value, error) {
+	comp := s.Compress()
+	return comp[:], nil
+}
+
 // SignMimc7 signs a message encoded as a big.Int in Zq using blake-512 hash
 // for buffer hashing and mimc7 for big.Int hashing.
 func (k *PrivateKey) SignMimc7(msg *big.Int) *Signature {

babyjub/eddsa_test.go

@@ -6,6 +6,9 @@ import (
 	"math/big"
 	"testing"
 
+	"database/sql"
+	"database/sql/driver"
+
 	"github.com/iden3/go-iden3-crypto/constants"
 	"github.com/iden3/go-iden3-crypto/utils"
 	"github.com/stretchr/testify/assert"
@@ -132,6 +135,18 @@ func TestCompressDecompress(t *testing.T) {
 	}
 }
 
+func TestScannerValuer(t *testing.T) {
+	privK := NewRandPrivKey()
+	var value driver.Valuer
+	var scan sql.Scanner
+	value = privK.SignPoseidon(big.NewInt(674238462))
+	scan = privK.SignPoseidon(big.NewInt(1))
+	fromDB, err := value.Value()
+	assert.NoError(t, err)
+	assert.NoError(t, scan.Scan(fromDB))
+	assert.Equal(t, value, scan)
+}
+
 func BenchmarkBabyjubEddsa(b *testing.B) {
 	var k PrivateKey
 	_, err := hex.Decode(k[:], []byte("0001020304050607080900010203040506070809000102030405060708090001"))

go.mod

@@ -7,4 +7,5 @@ require (
 	github.com/ethereum/go-ethereum v1.9.12
 	github.com/stretchr/testify v1.4.0
 	golang.org/x/crypto v0.0.0-20200311171314-f7b00557c8c4
+	golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd // indirect
 )

go.sum

@@ -50,8 +50,6 @@ github.com/dop251/goja v0.0.0-20200219165308-d1232e640a87/go.mod h1:Mw6PkjjMXWbT
 github.com/edsrzf/mmap-go v0.0.0-20160512033002-935e0e8a636c/go.mod h1:YO35OhQPt3KJa3ryjFM5Bs14WD66h8eGKpfaBNrHW5M=
 github.com/elastic/gosigar v0.8.1-0.20180330100440-37f05ff46ffa h1:XKAhUk/dtp+CV0VO6mhG2V7jA9vbcGcnYF/Ay9NjZrY=
 github.com/elastic/gosigar v0.8.1-0.20180330100440-37f05ff46ffa/go.mod h1:cdorVVzy1fhmEqmtgqkoE3bYtCfSCkVyjTyCIo22xvs=
-github.com/ethereum/go-ethereum v1.8.27 h1:d+gkiLaBDk5fn3Pe/xNVaMrB/ozI+AUB2IlVBp29IrY=
-github.com/ethereum/go-ethereum v1.8.27/go.mod h1:PwpWDrCLZrV+tfrhqqF6kPknbISMHaJv9Ln3kPCZLwY=
 github.com/ethereum/go-ethereum v1.9.12 h1:EPtimwsp/KGDSiXcNunzsI4kefdsMHZGJntKx3fvbaI=
 github.com/ethereum/go-ethereum v1.9.12/go.mod h1:PvsVkQmhZFx92Y+h2ylythYlheEDt/uBgFbl61Js/jo=
 github.com/fatih/color v1.3.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
@@ -76,15 +74,16 @@ github.com/graph-gophers/graphql-go v0.0.0-20191115155744-f33e81362277/go.mod h1
 github.com/hashicorp/golang-lru v0.0.0-20160813221303-0a025b7e63ad/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/huin/goupnp v0.0.0-20161224104101-679507af18f3/go.mod h1:MZ2ZmwcBpvOoJ22IJsc7va19ZwoheaBk43rKg12SKag=
-github.com/iden3/go-iden3 v0.0.5 h1:NV6HXnLmp+1YmKd2FmymzU6OAP77q1WWDcB/B+BUL9g=
 github.com/influxdata/influxdb v1.2.3-0.20180221223340-01288bdb0883/go.mod h1:qZna6X/4elxqT3yI9iZYdZrWWdeFOOprn86kgg4+IzY=
 github.com/jackpal/go-nat-pmp v1.0.2-0.20160603034137-1fa385a6f458/go.mod h1:QPH045xvCAeXUZOxsnwmrtiCoxIr9eob+4orBN1SBKc=
 github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
 github.com/julienschmidt/httprouter v1.1.1-0.20170430222011-975b5c4c7c21/go.mod h1:SYymIcj16QtmaHHD7aYtjjsJG7VTCxuUUipMqKk8s4w=
 github.com/karalabe/usb v0.0.0-20190919080040-51dc0efba356/go.mod h1:Od972xHfMJowv7NGVDiWVxk2zxnWgjLlJzE+F4F7AGU=
 github.com/kr/logfmt v0.0.0-20140226030751-b84e30acd515/go.mod h1:+0opPa2QZZtGFBFZlji/RkVcI2GknAs/DXo4wKdlNEc=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/mattn/go-colorable v0.1.0/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
@@ -138,8 +137,6 @@ github.com/tyler-smith/go-bip39 v1.0.1-0.20181017060643-dbb3b84ba2ef/go.mod h1:s
 github.com/urfave/cli v1.22.1/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=
 github.com/wsddn/go-ecdh v0.0.0-20161211032359-48726bab9208/go.mod h1:IotVbo4F+mw0EzQ08zFqg7pK3FebNXpaMsRy2RT+Ees=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20190621222207-cc06ce4a13d4 h1:ydJNl0ENAG67pFbB+9tfhiL2pYqLhfoaZFw/cjLhY4A=
-golang.org/x/crypto v0.0.0-20190621222207-cc06ce4a13d4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200311171314-f7b00557c8c4 h1:QmwruyY+bKbDDL0BaglrbZABEali68eoMFhTZpCjYVA=
 golang.org/x/crypto v0.0.0-20200311171314-f7b00557c8c4/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -154,12 +151,15 @@ golang.org/x/sys v0.0.0-20190412213103-97732733099d h1:+R4KGOnez64A81RvjARKc4UT5
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527 h1:uYVVQ9WP/Ds2ROhcaGPeIdVq0RIXVLwsHlnvJ+cT1So=
 golang.org/x/sys v0.0.0-20200302150141-5c8b2ff67527/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd h1:xhmwyvizuTgC2qz7ZlMluP20uW+C3Rm0FD/WLDX8884=
+golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys=
 gopkg.in/natefinch/npipe.v2 v2.0.0-20160621034901-c1b8fa8bdcce/go.mod h1:5AcXVHNjg+BDxry382+8OKon8SEWiKktQR07RKPsv1c=