[BUG] Bitcoin addresses generated are not valid (incorrect checksum)

[Emyrk]

Describe the bug

Bitcoin keys use base58 check (see https://en.bitcoin.it/wiki/Base58Check_encoding, for example: https://gobittest.appspot.com/Address). Addresses generated by this package are not valid Bitcoin addresses since their checksums are invalid.

The generator just generates random base58 text. I implemented a function that can fix checksums of a randomly generated address, it just requires base58 encode/decode. You can copy this small implementation into the Faker lib to not need to go get it: https://github.com/akamensky/base58/blob/master/base58.go. Or implement it yourself.

If base58 is in this package, I can make a PR that runs all bitcoin generated addressed through a checksum fix function and make sure they are valid.

To Reproduce

https://go.dev/play/p/No5BYCcsUk4

package main

import (
	"crypto/sha256"
	"fmt"

	"github.com/btcsuite/btcutil/base58"
	"github.com/jaswdr/faker"
)

func main() {
	fake := faker.New()
	address := fake.Crypto().BitcoinAddress()
	fmt.Println("Before:", address)
	_, _, err := base58.CheckDecode(address)
	if err != nil {
		fmt.Println("Failed:", err)
	} else {
		fmt.Println("Success!")
	}

	// Fix the address
	address = FixChecksum(address)
	fmt.Println("After:", address)
	_, _, err = base58.CheckDecode(address)
	if err != nil {
		fmt.Println("Failed:", err)
	} else {
		fmt.Println("Success!")
	}
}

func FixChecksum(addr string) string {
	decoded := base58.Decode(addr)

	// Remove the last 4 bytes
	decoded = decoded[:len(decoded)-4]

	// Find the checksum
	checksum := sha256.Sum256(decoded)
	checksum = sha256.Sum256(checksum[:])

	// Add back the 4 byte checksum
	decoded = append(decoded, checksum[:4]...)
	return base58.Encode(decoded)
}

Expected behavior

The address should pass the CheckDecode

[jaswdr]

thank you for the report @Emyrk, I'll apply this fix as soon as possible and release a new version.

[Emyrk]

Thanks! I was going to open a PR, but the requirement of base58 is annoying since golang does not support it natively.

With your no deps in go.mod, it has to be implemented here 😢

[jaswdr]

Fixed in #153 by simplifying the way bitcoin and etherium addresses are generated.