From 0c6a113b2446e7d4c6b8222fe63518dc2e01e8c1 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Wed, 16 Sep 2020 21:53:41 -0700 Subject: [PATCH] fscrypt: use sha256() instead of open coding Now that there's a library function that calculates the SHA-256 digest of a buffer in one step, use it instead of sha256_init() + sha256_update() + sha256_final(). Link: https://lore.kernel.org/r/20200917045341.324996-1-ebiggers@kernel.org Signed-off-by: Eric Biggers --- fs/crypto/fname.c | 23 +++++++---------------- 1 file changed, 7 insertions(+), 16 deletions(-) diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c index eb13408b50a7..f47b581d8a94 100644 --- a/fs/crypto/fname.c +++ b/fs/crypto/fname.c @@ -61,15 +61,6 @@ struct fscrypt_nokey_name { */ #define FSCRYPT_NOKEY_NAME_MAX offsetofend(struct fscrypt_nokey_name, sha256) -static void fscrypt_do_sha256(const u8 *data, unsigned int data_len, u8 *result) -{ - struct sha256_state sctx; - - sha256_init(&sctx); - sha256_update(&sctx, data, data_len); - sha256_final(&sctx, result); -} - static inline bool fscrypt_is_dot_dotdot(const struct qstr *str) { if (str->len == 1 && str->name[0] == '.') @@ -366,9 +357,9 @@ int fscrypt_fname_disk_to_usr(const struct inode *inode, } else { memcpy(nokey_name.bytes, iname->name, sizeof(nokey_name.bytes)); /* Compute strong hash of remaining part of name. */ - fscrypt_do_sha256(&iname->name[sizeof(nokey_name.bytes)], - iname->len - sizeof(nokey_name.bytes), - nokey_name.sha256); + sha256(&iname->name[sizeof(nokey_name.bytes)], + iname->len - sizeof(nokey_name.bytes), + nokey_name.sha256); size = FSCRYPT_NOKEY_NAME_MAX; } oname->len = base64_encode((const u8 *)&nokey_name, size, oname->name); @@ -497,7 +488,7 @@ bool fscrypt_match_name(const struct fscrypt_name *fname, { const struct fscrypt_nokey_name *nokey_name = (const void *)fname->crypto_buf.name; - u8 sha256[SHA256_DIGEST_SIZE]; + u8 digest[SHA256_DIGEST_SIZE]; if (likely(fname->disk_name.name)) { if (de_name_len != fname->disk_name.len) @@ -508,9 +499,9 @@ bool fscrypt_match_name(const struct fscrypt_name *fname, return false; if (memcmp(de_name, nokey_name->bytes, sizeof(nokey_name->bytes))) return false; - fscrypt_do_sha256(&de_name[sizeof(nokey_name->bytes)], - de_name_len - sizeof(nokey_name->bytes), sha256); - return !memcmp(sha256, nokey_name->sha256, sizeof(sha256)); + sha256(&de_name[sizeof(nokey_name->bytes)], + de_name_len - sizeof(nokey_name->bytes), digest); + return !memcmp(digest, nokey_name->sha256, sizeof(digest)); } EXPORT_SYMBOL_GPL(fscrypt_match_name);