package cmd import ( "crypto/rand" "encoding/base64" "fmt" "github.com/spf13/cobra" "golang.org/x/crypto/curve25519" ) func init() { rootCmd.AddCommand(&cobra.Command{ Use: "x25519", Short: "Generate key pair for x25519 key exchange", Run: func(cmd *cobra.Command, args []string) { if err := x25519(); err != nil { fmt.Println(err) } }, }) } func x25519() error { var publicKey []byte privateKey := make([]byte, curve25519.ScalarSize) if _, err := rand.Read(privateKey); err != nil { return err } // Modify random bytes using algorithm described at: // https://cr.yp.to/ecdh.html. privateKey[0] &= 248 privateKey[31] &= 127 privateKey[31] |= 64 publicKey, err := curve25519.X25519(privateKey, curve25519.Basepoint) if err != nil { return err } output := fmt.Sprintf("Private key: %v\nPublic key: %v", base64.RawURLEncoding.EncodeToString(privateKey), base64.RawURLEncoding.EncodeToString(publicKey)) fmt.Println(output) return nil }