Problem
You have a algorand account address, you want to derive the public key from it with Golang.
Solution
Install Algorand SDK:
1
| $ go get -u github.com/algorand/go-algorand-sdk/...
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
|
import (
"crypto/ed25519"
"crypto/sha512"
"encoding/base64"
algocrypto "github.com/algorand/go-algorand-sdk/crypto"
"github.com/algorand/go-algorand-sdk/types"
)
func algoAddrToPublicKey(address string) (ed25519.PublicKey, error) {
addr, err := types.DecodeAddress(address)
if err != nil {
return nil, err
}
bytes := [sha512.Size256]byte(addr)
return ed25519.PublicKey(bytes[:]), nil
}
func main() {
addr := "<wallet address, 58 characters>"
pubKey, _ := algoAddrToPublicKey(addr)
}
|
With the public key we can verify if a signed message is valid:
1
2
3
4
5
6
7
| msg := "message to sign"
rawSig := "<base64 signature string>"
sig, _ := base64.StdEncoding.DecodeString(rawSig)
valid := algocrypto.VerifyBytes(pubKey, []byte(msg), sig)
if valid {
fmt.Println("signature is valid")
}
|