SMB3.1.1: add defines for new signing negotiate context

Currently there are three supported signing algorithms
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/cifs/smb2pdu.h

@@ -323,6 +323,7 @@ struct smb2_negotiate_req {
 #define SMB2_NETNAME_NEGOTIATE_CONTEXT_ID	cpu_to_le16(5)
 #define SMB2_TRANSPORT_CAPABILITIES		cpu_to_le16(6)
 #define SMB2_RDMA_TRANSFORM_CAPABILITIES	cpu_to_le16(7)
+#define SMB2_SIGNING_CAPABILITIES		cpu_to_le16(8)
 #define SMB2_POSIX_EXTENSIONS_AVAILABLE		cpu_to_le16(0x100)
 
 struct smb2_neg_context {
@@ -416,6 +417,19 @@ struct smb2_rdma_transform_capabilities_context {
 	__le16	RDMATransformIds[1];
 } __packed;
 
+/* Signing algorithms */
+#define SIGNING_ALG_HMAC_SHA256	0
+#define SIGNING_ALG_AES_CMAC	1
+#define SIGNING_ALG_AES_GMAC	2
+
+struct smb2_signing_capabilities {
+	__le16	ContextType; /* 8 */
+	__le16	DataLength;
+	__u32	Reserved;
+	__le16	SigningAlgorithmCount;
+	__le16	SigningAlgorithms[];
+} __packed;
+
 #define POSIX_CTXT_DATA_LEN	16
 struct smb2_posix_neg_context {
 	__le16	ContextType; /* 0x100 */