refactor: generate ca now generates and writes its own private key.

internal/clis/hmpki/generate.go

@@ -5,28 +5,34 @@ import (
 )
 
 // Needed by all subcommands.
-var Output string
-
-// Needed by some subcommands.
-var KeyFile string
+var Name string
+var OutDir string
 
 func init() {
 	rootCmd.AddCommand(generateCmd)
 
-	// All "generate" commands output an artifact to a file,
-	// be it a key or a cert, etc.
+	// Name for artifacts being written to file(s).
 	generateCmd.PersistentFlags().StringVarP(
-		&Output,
-		"output",
-		"o",
+		&Name,
+		"name",
+		"n",
 		"",
-		"output filename",
+		"name of the artifact being benerated",
 	)
-	generateCmd.MarkPersistentFlagRequired("output")
-	generateCmd.MarkPersistentFlagFilename("output")
+	generateCmd.MarkPersistentFlagRequired("name")
+
+	// Output direcotry.
+	generateCmd.PersistentFlags().StringVar(
+		&OutDir,
+		"output-dir",
+		".",
+		"output directory for artifacts produced by this command, defaults to the current directory",
+	)
+	generateCmd.MarkPersistentFlagRequired("output-dir")
+	generateCmd.MarkPersistentFlagDirname("output-dir")
 }
 
 var generateCmd = &cobra.Command{
 	Use:   "generate",
-	Short: "Generate pki resources (keys/certs)",
+	Short: "Generate pki resources (cas/keys/certs)",
 }

internal/clis/hmpki/generate_ca.go

@@ -1,7 +1,6 @@
 package hmpki
 
 import (
-	"crypto/ecdsa"
 	"crypto/rand"
 	"crypto/x509"
 	"crypto/x509/pkix"
@@ -9,7 +8,7 @@ import (
 	"errors"
 	"math"
 	"math/big"
-	"os"
+	"path"
 	"time"
 
 	"git.handmadecities.com/HMC/shhh/pkg/pki"
@@ -18,41 +17,19 @@ import (
 
 func init() {
 	generateCmd.AddCommand(generateCACmd)
-
-	generateCACmd.Flags().StringVar(
-		&KeyFile,
-		"key-file",
-		"",
-		"File that contains the private key that will be associated to the CA",
-	)
-	generateCACmd.MarkFlagRequired("key-file")
-	generateCACmd.MarkFlagFilename("key-file")
 }
 
 var generateCACmd = &cobra.Command{
 	Use:   "ca",
 	Short: "Generate a Certificate Authority",
 	RunE: func(cmd *cobra.Command, args []string) error {
-		// Read key from KeyFile.
-		keyPemBytes, err := os.ReadFile(KeyFile)
-		if err != nil {
-			return err
-		}
-		privBlock, _ := pem.Decode(keyPemBytes)
-		if privBlock == nil || privBlock.Type != pki.PEMTypePrivateKey {
-			return errors.New("Invalid pem key file, or first block is not a private key")
-		}
-		rawKey, err := x509.ParsePKCS8PrivateKey(privBlock.Bytes)
-
-		key, ok := rawKey.(*ecdsa.PrivateKey)
-		if !ok {
-			return errors.New("key file did not contain an ecdsa private key")
-		}
+		// Private key for the ca.
+		key := pki.GenerateKey()
 
 		// Cryptographically random 64bit number as the serial.
 		sn, err := rand.Int(rand.Reader, big.NewInt(math.MaxInt64))
 		if err != nil {
-			errors.New("Could not generate a ca serial number")
+			return errors.New("Could not generate a ca serial number")
 		}
 		caTmpl := &x509.Certificate{
 			SerialNumber: sn,
@@ -87,17 +64,16 @@ var generateCACmd = &cobra.Command{
 			Bytes: caBytes,
 		})
 
-		caf, err := os.OpenFile(
-			Output,
-			// Write only, and fail if it alreay exists.
-			os.O_WRONLY|os.O_CREATE|os.O_EXCL,
-			pki.CertFilePerms,
-		)
+		// Write ca to disk.
+		cafn := path.Join(OutDir, Name+"_ca.crt")
+		err = createFileWith(cafn, caPEMBytes, pki.CertFilePerms)
 		if err != nil {
 			return err
 		}
-		defer caf.Close()
-		if _, err = caf.Write(caPEMBytes); err != nil {
+		// Write private key to disk.
+		keyfn := path.Join(OutDir, Name+"_ca.key")
+		err = createFileWith(keyfn, pki.MarshalKeyToPEM(key), pki.PrivateKeyFilePerms)
+		if err != nil {
 			return err
 		}