Certificates

certificate-list.go

package main

import (
	"crypto"
	"crypto/rand"
	"crypto/sha256"
	"encoding/base64"
	"fmt"
	"time"

	"github.com/github/smimesign/certstore"
)

func main() {

	if err := certList(); err != nil {
		fmt.Printf("Error: %s\n", err)
	}

}

func certList() error {
	store, err := certstore.Open()
	if err != nil {
		return fmt.Errorf("opening certstore: %w", err)
	}
	defer store.Close()

	idents, err := store.Identities()
	if err != nil {
		return fmt.Errorf("getting identities: %w", err)
	}

	for _, ident := range idents {
		tryIdent(ident)

	}

	return nil
}

func tryIdent(ident certstore.Identity) {
	defer fmt.Println("\n")

	crt, err := ident.Certificate()
	if err != nil {
		fmt.Printf("Not a cert: %s\n", err)
		return
	}

	fmt.Printf("Subject: %s\nIssuer: %s\n", crt.Subject.String(), crt.Issuer.String())

	nonce := time.Now().String()
	fmt.Printf("msg: %s\n", nonce)

	signer, err := ident.Signer()
	if err != nil {
		fmt.Printf("error getting signer: %s", err)
		return
	}

	// Digest and sign our message.
	digest := sha256.Sum256([]byte(nonce))
	signature, err := signer.Sign(rand.Reader, digest[:], crypto.SHA256)
	if err != nil {
		fmt.Printf("error signing: %s", err)
		return
	}

	fmt.Printf("sig: %s\n", base64.StdEncoding.EncodeToString(signature))
}