From 9a394d1208147715b8a365f44b4e7bfbb2094748 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 15 Aug 2019 12:01:12 +0300 Subject: [PATCH] fs: cifs: move from the crypto cipher API to the new DES library interface Some legacy code in the CIFS driver uses single DES to calculate some password hash, and uses the crypto cipher API to do so. Given that there is no point in invoking an accelerated cipher for doing 56-bit symmetric encryption on a single 8-byte block of input, the flexibility of the crypto cipher API does not add much value here, and so we're much better off using a library call into the generic C implementation. Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- fs/cifs/Kconfig | 2 +- fs/cifs/cifsfs.c | 1 - fs/cifs/smbencrypt.c | 18 +++++++++--------- 3 files changed, 10 insertions(+), 11 deletions(-) diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig index b16219e5dac9..350bc3061656 100644 --- a/fs/cifs/Kconfig +++ b/fs/cifs/Kconfig @@ -16,7 +16,7 @@ config CIFS select CRYPTO_GCM select CRYPTO_ECB select CRYPTO_AES - select CRYPTO_DES + select CRYPTO_LIB_DES select KEYS help This is the client VFS module for the SMB3 family of NAS protocols, diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 3289b566463f..4e2f74894e9b 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -1601,7 +1601,6 @@ MODULE_DESCRIPTION ("VFS to access SMB3 servers e.g. Samba, Macs, Azure and Windows (and " "also older servers complying with the SNIA CIFS Specification)"); MODULE_VERSION(CIFS_VERSION); -MODULE_SOFTDEP("pre: des"); MODULE_SOFTDEP("pre: ecb"); MODULE_SOFTDEP("pre: hmac"); MODULE_SOFTDEP("pre: md4"); diff --git a/fs/cifs/smbencrypt.c b/fs/cifs/smbencrypt.c index 2b6d87bfdf8e..39a938443e3e 100644 --- a/fs/cifs/smbencrypt.c +++ b/fs/cifs/smbencrypt.c @@ -11,13 +11,14 @@ */ -#include #include #include +#include #include #include #include #include +#include #include "cifs_fs_sb.h" #include "cifs_unicode.h" #include "cifspdu.h" @@ -58,19 +59,18 @@ static int smbhash(unsigned char *out, const unsigned char *in, unsigned char *key) { unsigned char key2[8]; - struct crypto_cipher *tfm_des; + struct des_ctx ctx; str_to_key(key, key2); - tfm_des = crypto_alloc_cipher("des", 0, 0); - if (IS_ERR(tfm_des)) { - cifs_dbg(VFS, "could not allocate des crypto API\n"); - return PTR_ERR(tfm_des); + if (fips_enabled) { + cifs_dbg(VFS, "FIPS compliance enabled: DES not permitted\n"); + return -ENOENT; } - crypto_cipher_setkey(tfm_des, key2, 8); - crypto_cipher_encrypt_one(tfm_des, out, in); - crypto_free_cipher(tfm_des); + des_expand_key(&ctx, key2, DES_KEY_SIZE); + des_encrypt(&ctx, out, in); + memzero_explicit(&ctx, sizeof(ctx)); return 0; } -- 2.30.2