From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:37490 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404354AbfGXTya (ORCPT ); Wed, 24 Jul 2019 15:54:30 -0400 Received: from ebiggers-linuxstation.mtv.corp.google.com (unknown [104.132.1.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 003E922BED for ; Wed, 24 Jul 2019 19:54:28 +0000 (UTC) From: Eric Biggers Subject: [PATCH 4/4] fscrypt: use ENOPKG when crypto API support missing Date: Wed, 24 Jul 2019 12:54:22 -0700 Message-Id: <20190724195422.42495-5-ebiggers@kernel.org> In-Reply-To: <20190724195422.42495-1-ebiggers@kernel.org> References: <20190724195422.42495-1-ebiggers@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fscrypt-owner@vger.kernel.org To: linux-fscrypt@vger.kernel.org List-ID: From: Eric Biggers Return ENOPKG rather than ENOENT when trying to open a file that's encrypted using algorithms not available in the kernel's crypto API. This avoids an ambiguity, since ENOENT is also returned when the file doesn't exist. Note: this is the same approach I'm taking for fs-verity. Signed-off-by: Eric Biggers --- fs/crypto/keyinfo.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c index b75678587c3a85..2129943002335c 100644 --- a/fs/crypto/keyinfo.c +++ b/fs/crypto/keyinfo.c @@ -237,13 +237,14 @@ allocate_skcipher_for_mode(struct fscrypt_mode *mode, const u8 *raw_key, tfm = crypto_alloc_skcipher(mode->cipher_str, 0, 0); if (IS_ERR(tfm)) { - if (PTR_ERR(tfm) == -ENOENT) + if (PTR_ERR(tfm) == -ENOENT) { fscrypt_warn(inode, "Missing crypto API support for %s (API name: \"%s\")", mode->friendly_name, mode->cipher_str); - else - fscrypt_err(inode, "Error allocating '%s' transform: %ld", - mode->cipher_str, PTR_ERR(tfm)); + return ERR_PTR(-ENOPKG); + } + fscrypt_err(inode, "Error allocating '%s' transform: %ld", + mode->cipher_str, PTR_ERR(tfm)); return tfm; } if (unlikely(!mode->logged_impl_name)) { @@ -389,13 +390,14 @@ static int derive_essiv_salt(const u8 *key, int keysize, u8 *salt) tfm = crypto_alloc_shash("sha256", 0, 0); if (IS_ERR(tfm)) { - if (PTR_ERR(tfm) == -ENOENT) + if (PTR_ERR(tfm) == -ENOENT) { fscrypt_warn(NULL, "Missing crypto API support for SHA-256"); - else - fscrypt_err(NULL, - "Error allocating SHA-256 transform: %ld", - PTR_ERR(tfm)); + return -ENOPKG; + } + fscrypt_err(NULL, + "Error allocating SHA-256 transform: %ld", + PTR_ERR(tfm)); return PTR_ERR(tfm); } prev_tfm = cmpxchg(&essiv_hash_tfm, NULL, tfm); -- 2.22.0.657.g960e92d24f-goog