1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
import { typedView } from '@exodus/bytes/array.js'
import { toBase58, fromBase58 } from '@exodus/bytes/base58.js'
import { assertU8 } from './_utils.js'
const E_CHECKSUM = 'Invalid checksum'
// checksum length is 4, i.e. only the first 4 bytes of the hash are used
function encodeWithChecksum(arr, checksum) {
// arr type in already validated in input
const res = new Uint8Array(arr.length + 4)
res.set(arr, 0)
res.set(checksum.subarray(0, 4), arr.length)
return toBase58(res)
}
function decodeWithChecksum(str) {
const arr = fromBase58(str) // checks input
const payloadSize = arr.length - 4
if (payloadSize < 0) throw new Error(E_CHECKSUM)
return [arr.subarray(0, payloadSize), arr.subarray(payloadSize)]
}
function assertChecksum(c, r) {
if ((c[0] ^ r[0]) | (c[1] ^ r[1]) | (c[2] ^ r[2]) | (c[3] ^ r[3])) throw new Error(E_CHECKSUM)
}
export const makeBase58check = (hashAlgo, hashAlgoSync) => {
const apis = {
async encode(arr) {
assertU8(arr)
return encodeWithChecksum(arr, await hashAlgo(arr))
},
async decode(str, format = 'uint8') {
const [payload, checksum] = decodeWithChecksum(str)
assertChecksum(checksum, await hashAlgo(payload))
return typedView(payload, format)
},
}
if (!hashAlgoSync) return apis
return {
...apis,
encodeSync(arr) {
assertU8(arr)
return encodeWithChecksum(arr, hashAlgoSync(arr))
},
decodeSync(str, format = 'uint8') {
const [payload, checksum] = decodeWithChecksum(str)
assertChecksum(checksum, hashAlgoSync(payload))
return typedView(payload, format)
},
}
}
|
