Commit 29a98c1c authored by Eric Biggers's avatar Eric Biggers
Browse files

fscrypt: use ENOPKG when crypto API support missing 



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: default avatarEric Biggers <ebiggers@google.com>
parent a4d14e91

fs/crypto/keyinfo.c

+11 −9
Original line number Diff line number Diff line
@@ -237,11 +237,12 @@ 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

			return ERR_PTR(-ENOPKG);

		}

		fscrypt_err(inode, "Error allocating '%s' transform: %ld",

			    mode->cipher_str, PTR_ERR(tfm));

		return tfm;
@@ -389,10 +390,11 @@ 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

				return -ENOPKG;

			}

			fscrypt_err(NULL,

				    "Error allocating SHA-256 transform: %ld",

				    PTR_ERR(tfm));

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