diff options
Diffstat (limited to 'common/icap.go')
| -rw-r--r-- | common/icap.go | 190 |
1 files changed, 0 insertions, 190 deletions
diff --git a/common/icap.go b/common/icap.go deleted file mode 100644 index a36e669b3..000000000 --- a/common/icap.go +++ /dev/null @@ -1,190 +0,0 @@ -// 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 <http://www.gnu.org/licenses/>. - -// 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, "") -} |