tls: improve tls.getCACertificates() to simplify certificate handling

Author: haramj

lib/tls.js

@@ -168,20 +168,29 @@ function cacheDefaultCACertificates() {
   return defaultCACertificates;
 }
 
+function getCACertificatesAsStrings(type = 'default') {
+  validateString(type, 'type');
+
+  switch (type) {
+    case 'default':
+      return cacheDefaultCACertificates();
+    case 'bundled':
+      return cacheBundledRootCertificates();
+    case 'system':
+      return cacheSystemCACertificates();
+    case 'extra':
+      return cacheExtraCACertificates();
+    default:
+      throw new ERR_INVALID_ARG_VALUE('type', type);
+  }
+}
+
 function getCACertificates(options = undefined) {
   if (typeof options === 'string' || options === undefined) {
-    const type = (typeof options === 'string') ? options : 'default';
-
-    validateString(type, 'type');
+    return getCACertificatesAsStrings(options);
+  }
 
-    switch (type) {
-      case 'default': return cacheDefaultCACertificates();
-      case 'bundled': return cacheBundledRootCertificates();
-      case 'system': return cacheSystemCACertificates();
-      case 'extra': return cacheExtraCACertificates();
-      default: throw new ERR_INVALID_ARG_VALUE('type', type);
-    }
-  } else if (typeof options === 'object' && options !== null) {
+  if (typeof options === 'object' && options !== null) {
     const {
       type = 'default',
       format = 'pem',
@@ -190,44 +199,24 @@ function getCACertificates(options = undefined) {
     validateString(type, 'type');
     validateOneOf(format, 'format', ['pem', 'der', 'x509', 'string', 'buffer']);
 
-    let effectiveFormat = format;
-    if (format === 'string') {
-      effectiveFormat = 'pem';
-    } else if (format === 'buffer') {
-      effectiveFormat = 'der';
-    }
+    const certs = getCACertificatesAsStrings(type);
 
-    let certs;
-    switch (type) {
-      case 'default': certs = cacheDefaultCACertificates(); break;
-      case 'bundled': certs = cacheBundledRootCertificates(); break;
-      case 'system': certs = cacheSystemCACertificates(); break;
-      case 'extra': certs = cacheExtraCACertificates(); break;
-      default: throw new ERR_INVALID_ARG_VALUE('type', type);
+    if (format === 'x509') {
+      return certs.map((cert) => new X509Certificate(cert));
     }
 
-    if (effectiveFormat === 'pem') {
-      return certs.map((cert) => {
-        if (typeof cert === 'string') {
-          return cert;
-        }
-        return `-----BEGIN CERTIFICATE-----\n${cert.toString('base64').match(/.{1,64}/g).join('\n')}\n-----END CERTIFICATE-----`;
-      });
+    if (format === 'pem' || format === 'string') {
+      return certs;
     }
 
     const buffers = certs.map((cert) => {
-      if (Buffer.isBuffer(cert)) {
-        return cert;
-      }
       const base64 = cert.replace(/(?:\s|-----BEGIN CERTIFICATE-----|-----END CERTIFICATE-----)+/g, '');
       return Buffer.from(base64, 'base64');
     });
 
-    if (effectiveFormat === 'der') {
+    if (format === 'der' || format === 'buffer') {
       return buffers;
     }
-
-    return buffers.map((buf) => new X509Certificate(buf));
   }
 
   throw new ERR_INVALID_ARG_TYPE('options', ['string', 'object'], options);