From 0fba4e28de2d0b5b8a262f512b65e487ded0c6e1 Mon Sep 17 00:00:00 2001 From: Paul Kehrer Date: Thu, 12 Jul 2018 22:19:21 +0530 Subject: raise valueerror for null x25519 derived keys (#4332) * raise valueerror for null x25519 derived keys OpenSSL errors when it hits this edge case and a null shared key is bad anyway so let's raise an error * empty commit --- src/cryptography/hazmat/backends/openssl/x25519.py | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'src/cryptography/hazmat/backends/openssl/x25519.py') diff --git a/src/cryptography/hazmat/backends/openssl/x25519.py b/src/cryptography/hazmat/backends/openssl/x25519.py index 5599c2fd..983ece6a 100644 --- a/src/cryptography/hazmat/backends/openssl/x25519.py +++ b/src/cryptography/hazmat/backends/openssl/x25519.py @@ -71,5 +71,9 @@ class _X25519PrivateKey(object): self._backend.openssl_assert(keylen[0] > 0) buf = self._backend._ffi.new("unsigned char[]", keylen[0]) res = self._backend._lib.EVP_PKEY_derive(ctx, buf, keylen) - self._backend.openssl_assert(res == 1) + if res != 1: + raise ValueError( + "Null shared key derived from public/private pair." + ) + return self._backend._ffi.buffer(buf, keylen[0])[:] -- cgit v1.2.3