smb3.1.1: set gcm256 when requested

update smb encryption code to set 32 byte key length and to
set gcm256 when requested on mount.

Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Steve French 2020-10-15 23:41:40 -05:00
parent fd08f2dbf0
commit 63ca565635
4 changed files with 17 additions and 6 deletions

View file

@ -58,6 +58,7 @@
#define SMB2_HMACSHA256_SIZE (32)
#define SMB2_CMACAES_SIZE (16)
#define SMB3_SIGNKEY_SIZE (16)
#define SMB3_GCM256_CRYPTKEY_SIZE (32)
/* Maximum buffer size value we can send with 1 credit */
#define SMB2_MAX_BUFFER_SIZE 65536

View file

@ -3820,7 +3820,8 @@ fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, unsigned int orig_len,
tr_hdr->ProtocolId = SMB2_TRANSFORM_PROTO_NUM;
tr_hdr->OriginalMessageSize = cpu_to_le32(orig_len);
tr_hdr->Flags = cpu_to_le16(0x01);
if (cipher_type == SMB2_ENCRYPTION_AES128_GCM)
if ((cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
(cipher_type == SMB2_ENCRYPTION_AES256_GCM))
get_random_bytes(&tr_hdr->Nonce, SMB3_AES_GCM_NONCE);
else
get_random_bytes(&tr_hdr->Nonce, SMB3_AES_CCM_NONCE);
@ -3954,7 +3955,12 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst,
tfm = enc ? server->secmech.ccmaesencrypt :
server->secmech.ccmaesdecrypt;
rc = crypto_aead_setkey(tfm, key, SMB3_SIGN_KEY_SIZE);
if (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
rc = crypto_aead_setkey(tfm, key, SMB3_GCM256_CRYPTKEY_SIZE);
else
rc = crypto_aead_setkey(tfm, key, SMB3_SIGN_KEY_SIZE);
if (rc) {
cifs_server_dbg(VFS, "%s: Failed to set aead key %d\n", __func__, rc);
return rc;
@ -3992,7 +3998,8 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst,
goto free_sg;
}
if (server->cipher_type == SMB2_ENCRYPTION_AES128_GCM)
if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
(server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
memcpy(iv, (char *)tr_hdr->Nonce, SMB3_AES_GCM_NONCE);
else {
iv[0] = 3;

View file

@ -352,6 +352,7 @@ struct smb2_preauth_neg_context {
/* Encryption Algorithms Ciphers */
#define SMB2_ENCRYPTION_AES128_CCM cpu_to_le16(0x0001)
#define SMB2_ENCRYPTION_AES128_GCM cpu_to_le16(0x0002)
/* we currently do not request AES256_CCM since presumably GCM faster */
#define SMB2_ENCRYPTION_AES256_CCM cpu_to_le16(0x0003)
#define SMB2_ENCRYPTION_AES256_GCM cpu_to_le16(0x0004)

View file

@ -849,12 +849,13 @@ smb3_crypto_aead_allocate(struct TCP_Server_Info *server)
struct crypto_aead *tfm;
if (!server->secmech.ccmaesencrypt) {
if (server->cipher_type == SMB2_ENCRYPTION_AES128_GCM)
if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
(server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
else
tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
if (IS_ERR(tfm)) {
cifs_server_dbg(VFS, "%s: Failed to alloc encrypt aead\n",
cifs_server_dbg(VFS, "%s: Failed alloc encrypt aead\n",
__func__);
return PTR_ERR(tfm);
}
@ -862,7 +863,8 @@ smb3_crypto_aead_allocate(struct TCP_Server_Info *server)
}
if (!server->secmech.ccmaesdecrypt) {
if (server->cipher_type == SMB2_ENCRYPTION_AES128_GCM)
if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
(server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
else
tfm = crypto_alloc_aead("ccm(aes)", 0, 0);