diff --git a/common/big.go b/common/big.go
index a5d512d0d..4ce87ee0c 100644
--- a/common/big.go
+++ b/common/big.go
@@ -27,6 +27,9 @@ var (
BigTrue = Big1
BigFalse = Big0
Big32 = big.NewInt(32)
+ Big36 = big.NewInt(36)
+ Big97 = big.NewInt(97)
+ Big98 = big.NewInt(98)
Big256 = big.NewInt(0xff)
Big257 = big.NewInt(257)
MaxBig = String2Big("0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff")
diff --git a/common/icap.go b/common/icap.go
new file mode 100644
index 000000000..a36e669b3
--- /dev/null
+++ b/common/icap.go
@@ -0,0 +1,190 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see .
+
+// Spec at https://github.com/ethereum/wiki/wiki/ICAP:-Inter-exchange-Client-Address-Protocol
+
+package common
+
+import (
+ "errors"
+ "math/big"
+ "strconv"
+ "strings"
+)
+
+var (
+ Base36Chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ ICAPLengthError = errors.New("Invalid ICAP length")
+ ICAPEncodingError = errors.New("Invalid ICAP encoding")
+ ICAPChecksumError = errors.New("Invalid ICAP checksum")
+ ICAPCountryCodeError = errors.New("Invalid ICAP country code")
+ ICAPAssetIdentError = errors.New("Invalid ICAP asset identifier")
+ ICAPInstCodeError = errors.New("Invalid ICAP institution code")
+ ICAPClientIdentError = errors.New("Invalid ICAP client identifier")
+)
+
+func ICAPToAddress(s string) (Address, error) {
+ switch len(s) {
+ case 35: // "XE" + 2 digit checksum + 31 base-36 chars of address
+ return parseICAP(s)
+ case 34: // "XE" + 2 digit checksum + 30 base-36 chars of address
+ return parseICAP(s)
+ case 20: // "XE" + 2 digit checksum + 3-char asset identifier +
+ // 4-char institution identifier + 9-char institution client identifier
+ return parseIndirectICAP(s)
+ default:
+ return Address{}, ICAPLengthError
+ }
+}
+
+func parseICAP(s string) (Address, error) {
+ if !strings.HasPrefix(s, "XE") {
+ return Address{}, ICAPCountryCodeError
+ }
+ if err := validCheckSum(s); err != nil {
+ return Address{}, err
+ }
+ // checksum is ISO13616, Ethereum address is base-36
+ bigAddr, _ := new(big.Int).SetString(s[4:], 36)
+ return BigToAddress(bigAddr), nil
+}
+
+func parseIndirectICAP(s string) (Address, error) {
+ if !strings.HasPrefix(s, "XE") {
+ return Address{}, ICAPCountryCodeError
+ }
+ if s[4:7] != "ETH" {
+ return Address{}, ICAPAssetIdentError
+ }
+ if err := validCheckSum(s); err != nil {
+ return Address{}, err
+ }
+ // TODO: integrate with ICAP namereg
+ return Address{}, errors.New("not implemented")
+}
+
+func AddressToICAP(a Address) (string, error) {
+ enc := base36Encode(a.Big())
+ // zero padd encoded address to Direct ICAP length if needed
+ if len(enc) < 30 {
+ enc = join(strings.Repeat("0", 30-len(enc)), enc)
+ }
+ icap := join("XE", checkDigits(enc), enc)
+ return icap, nil
+}
+
+// TODO: integrate with ICAP namereg when it's available
+func AddressToIndirectICAP(a Address, instCode string) (string, error) {
+ // return addressToIndirectICAP(a, instCode)
+ return "", errors.New("not implemented")
+}
+
+func addressToIndirectICAP(a Address, instCode string) (string, error) {
+ // TODO: add addressToClientIdent which grabs client ident from ICAP namereg
+ //clientIdent := addressToClientIdent(a)
+ clientIdent := "todo"
+ return clientIdentToIndirectICAP(instCode, clientIdent)
+}
+
+func clientIdentToIndirectICAP(instCode, clientIdent string) (string, error) {
+ if len(instCode) != 4 || !validBase36(instCode) {
+ return "", ICAPInstCodeError
+ }
+ if len(clientIdent) != 9 || !validBase36(instCode) {
+ return "", ICAPClientIdentError
+ }
+
+ // currently ETH is only valid asset identifier
+ s := join("ETH", instCode, clientIdent)
+ return join("XE", checkDigits(s), s), nil
+}
+
+// https://en.wikipedia.org/wiki/International_Bank_Account_Number#Validating_the_IBAN
+func validCheckSum(s string) error {
+ s = join(s[4:], s[:4])
+ expanded, err := iso13616Expand(s)
+ if err != nil {
+ return err
+ }
+ checkSumNum, _ := new(big.Int).SetString(expanded, 10)
+ if checkSumNum.Mod(checkSumNum, Big97).Cmp(Big1) != 0 {
+ return ICAPChecksumError
+ }
+ return nil
+}
+
+func checkDigits(s string) string {
+ expanded, _ := iso13616Expand(strings.Join([]string{s, "XE00"}, ""))
+ num, _ := new(big.Int).SetString(expanded, 10)
+ num.Sub(Big98, num.Mod(num, Big97))
+
+ checkDigits := num.String()
+ // zero padd checksum
+ if len(checkDigits) == 1 {
+ checkDigits = join("0", checkDigits)
+ }
+ return checkDigits
+}
+
+// not base-36, but expansion to decimal literal: A = 10, B = 11, ... Z = 35
+func iso13616Expand(s string) (string, error) {
+ var parts []string
+ if !validBase36(s) {
+ return "", ICAPEncodingError
+ }
+ for _, c := range s {
+ i := uint64(c)
+ if i >= 65 {
+ parts = append(parts, strconv.FormatUint(uint64(c)-55, 10))
+ } else {
+ parts = append(parts, string(c))
+ }
+ }
+ return join(parts...), nil
+}
+
+func base36Encode(i *big.Int) string {
+ var chars []rune
+ x := new(big.Int)
+ for {
+ x.Mod(i, Big36)
+ chars = append(chars, rune(Base36Chars[x.Uint64()]))
+ i.Div(i, Big36)
+ if i.Cmp(Big0) == 0 {
+ break
+ }
+ }
+ // reverse slice
+ for i, j := 0, len(chars)-1; i < j; i, j = i+1, j-1 {
+ chars[i], chars[j] = chars[j], chars[i]
+ }
+ return string(chars)
+}
+
+func validBase36(s string) bool {
+ for _, c := range s {
+ i := uint64(c)
+ // 0-9 or A-Z
+ if i < 48 || (i > 57 && i < 65) || i > 90 {
+ return false
+ }
+ }
+ return true
+}
+
+func join(s ...string) string {
+ return strings.Join(s, "")
+}
diff --git a/common/icap_test.go b/common/icap_test.go
new file mode 100644
index 000000000..6306686d1
--- /dev/null
+++ b/common/icap_test.go
@@ -0,0 +1,91 @@
+// Copyright 2015 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see .
+
+package common
+
+import "testing"
+
+/* More test vectors:
+https://github.com/ethereum/web3.js/blob/master/test/iban.fromAddress.js
+https://github.com/ethereum/web3.js/blob/master/test/iban.toAddress.js
+https://github.com/ethereum/web3.js/blob/master/test/iban.isValid.js
+https://github.com/ethereum/libethereum/blob/develop/test/libethcore/icap.cpp
+*/
+
+type icapTest struct {
+ name string
+ addr string
+ icap string
+}
+
+var icapOKTests = []icapTest{
+ {"Direct1", "0x52dc504a422f0e2a9e7632a34a50f1a82f8224c7", "XE499OG1EH8ZZI0KXC6N83EKGT1BM97P2O7"},
+ {"Direct2", "0x11c5496aee77c1ba1f0854206a26dda82a81d6d8", "XE1222Q908LN1QBBU6XUQSO1OHWJIOS46OO"},
+ {"DirectZeroPrefix", "0x00c5496aee77c1ba1f0854206a26dda82a81d6d8", "XE7338O073KYGTWWZN0F2WZ0R8PX5ZPPZS"},
+ {"DirectDoubleZeroPrefix", "0x0000a5327eab78357cbf2ae8f3d49fd9d90c7d22", "XE0600DQK33XDTYUCRI0KYM5ELAKXDWWF6"},
+}
+
+var icapInvalidTests = []icapTest{
+ {"DirectInvalidCheckSum", "", "XE7438O073KYGTWWZN0F2WZ0R8PX5ZPPZS"},
+ {"DirectInvalidCountryCode", "", "XD7338O073KYGTWWZN0F2WZ0R8PX5ZPPZS"},
+ {"DirectInvalidLength36", "", "XE499OG1EH8ZZI0KXC6N83EKGT1BM97P2O77"},
+ {"DirectInvalidLength33", "", "XE499OG1EH8ZZI0KXC6N83EKGT1BM97P2"},
+
+ {"IndirectInvalidCheckSum", "", "XE35ETHXREGGOPHERSSS"},
+ {"IndirectInvalidAssetIdentifier", "", "XE34ETHXREGGOPHERSSS"},
+ {"IndirectInvalidLength19", "", "XE34ETHXREGGOPHERSS"},
+ {"IndirectInvalidLength21", "", "XE34ETHXREGGOPHERSSSS"},
+}
+
+func TestICAPOK(t *testing.T) {
+ for _, test := range icapOKTests {
+ decodeEncodeTest(HexToAddress(test.addr), test.icap, t)
+ }
+}
+
+func TestICAPInvalid(t *testing.T) {
+ for _, test := range icapInvalidTests {
+ failedDecodingTest(test.icap, t)
+ }
+}
+
+func decodeEncodeTest(addr0 Address, icap0 string, t *testing.T) {
+ icap1, err := AddressToICAP(addr0)
+ if err != nil {
+ t.Errorf("ICAP encoding failed: %s", err)
+ }
+ if icap1 != icap0 {
+ t.Errorf("ICAP mismatch: have: %s want: %s", icap1, icap0)
+ }
+
+ addr1, err := ICAPToAddress(icap0)
+ if err != nil {
+ t.Errorf("ICAP decoding failed: %s", err)
+ }
+ if addr1 != addr0 {
+ t.Errorf("Address mismatch: have: %x want: %x", addr1, addr0)
+ }
+}
+
+func failedDecodingTest(icap string, t *testing.T) {
+ addr, err := ICAPToAddress(icap)
+ if err == nil {
+ t.Errorf("Expected ICAP decoding to fail.")
+ }
+ if addr != (Address{}) {
+ t.Errorf("Expected empty Address on failed ICAP decoding.")
+ }
+}
diff --git a/crypto/key.go b/crypto/key.go
index 35139b67f..4ec43dfd7 100644
--- a/crypto/key.go
+++ b/crypto/key.go
@@ -22,6 +22,7 @@ import (
"encoding/hex"
"encoding/json"
"io"
+ "strings"
"github.com/ethereum/go-ethereum/common"
"github.com/pborman/uuid"
@@ -143,3 +144,24 @@ func NewKey(rand io.Reader) *Key {
return NewKeyFromECDSA(privateKeyECDSA)
}
+
+// generate key whose address fits into < 155 bits so it can fit into
+// the Direct ICAP spec. for simplicity and easier compatibility with
+// other libs, we retry until the first byte is 0.
+func NewKeyForDirectICAP(rand io.Reader) *Key {
+ randBytes := make([]byte, 64)
+ _, err := rand.Read(randBytes)
+ if err != nil {
+ panic("key generation: could not read from random source: " + err.Error())
+ }
+ reader := bytes.NewReader(randBytes)
+ privateKeyECDSA, err := ecdsa.GenerateKey(S256(), reader)
+ if err != nil {
+ panic("key generation: ecdsa.GenerateKey failed: " + err.Error())
+ }
+ key := NewKeyFromECDSA(privateKeyECDSA)
+ if !strings.HasPrefix(key.Address.Hex(), "0x00") {
+ return NewKeyForDirectICAP(rand)
+ }
+ return key
+}
diff --git a/crypto/key_store_test.go b/crypto/key_store_test.go
index fda87ddc8..de4a21dcf 100644
--- a/crypto/key_store_test.go
+++ b/crypto/key_store_test.go
@@ -20,6 +20,7 @@ import (
"encoding/hex"
"fmt"
"reflect"
+ "strings"
"testing"
"github.com/ethereum/go-ethereum/common"
@@ -223,3 +224,10 @@ func loadKeyStoreTestV1(file string, t *testing.T) map[string]KeyStoreTestV1 {
}
return tests
}
+
+func TestKeyForDirectICAP(t *testing.T) {
+ key := NewKeyForDirectICAP(randentropy.Reader)
+ if !strings.HasPrefix(key.Address.Hex(), "0x00") {
+ t.Errorf("Expected first address byte to be zero, have: %s", key.Address.Hex())
+ }
+}