crypto: better docs for cases where peer's public key is invalid

changes in c++ are in the computeSecret function, but the thrown
exception that was moved to JS land was in BufferToPoint
function, here i let the allocation error be thrown so the only value
returned is the nullptr that i use later to catch the error in
computeSecret, to then construct the exception in JS land.

an ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY error was added to errors.js
and with that, subsequent changes to docs and tests were made.

PR-URL: https://github.com/nodejs/node/pull/16849
Refs: https://www.iacr.org/archive/pkc2003/25670211/25670211.pdf
Fixes: https://github.com/nodejs/node/issues/16625
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

1 files changed, 14 insertions, 6 deletions

diff --git a/test/parallel/test-crypto-dh.js b/test/parallel/test-crypto-dh.js
index c162d660bd..d55540dd88 100644
--- a/test/parallel/test-crypto-dh.js
+++ b/test/parallel/test-crypto-dh.js
@@ -222,9 +222,13 @@ if (availableCurves.has('prime256v1') && availableCurves.has('secp256k1')) {
   const ecdh3 = crypto.createECDH('secp256k1');
   const key3 = ecdh3.generateKeys();
 
-  assert.throws(() => {
-    ecdh2.computeSecret(key3, 'latin1', 'buffer');
-  }, /^Error: Failed to translate Buffer to a EC_POINT$/);
+  common.expectsError(
+    () => ecdh2.computeSecret(key3, 'latin1', 'buffer'),
+    {
+      code: 'ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY',
+      type: Error,
+      message: 'Public key is not valid for specified curve'
+    });
 
   // ECDH should allow .setPrivateKey()/.setPublicKey()
   const ecdh4 = crypto.createECDH('prime256v1');
@@ -331,9 +335,13 @@ if (availableCurves.has('prime256v1') && availableHashes.has('sha256')) {
   const invalidKey = Buffer.alloc(65);
   invalidKey.fill('\0');
   curve.generateKeys();
-  assert.throws(() => {
-    curve.computeSecret(invalidKey);
-  }, /^Error: Failed to translate Buffer to a EC_POINT$/);
+  common.expectsError(
+    () => curve.computeSecret(invalidKey),
+    {
+      code: 'ERR_CRYPTO_ECDH_INVALID_PUBLIC_KEY',
+      type: Error,
+      message: 'Public key is not valid for specified curve'
+    });
   // Check that signing operations are not impacted by the above error.
   const ecPrivateKey =
     '-----BEGIN EC PRIVATE KEY-----\n' +