s3: Refactor smbd_smb2_request_process_negprot

Breakout smb2_protocol_dialect_match to support future work in
fsctl_validate_neg_info.

Signed-off-by: Ira Cooper <ira@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

2 files changed, 80 insertions, 63 deletions

diff --git a/source3/smbd/globals.h b/source3/smbd/globals.h
index 28e4f944303..d9ca5e31b04 100644
--- a/source3/smbd/globals.h
+++ b/source3/smbd/globals.h
@@ -260,6 +260,9 @@ NTSTATUS smbd_smb2_request_verify_creditcharge(struct smbd_smb2_request *req,
 NTSTATUS smbd_smb2_request_verify_sizes(struct smbd_smb2_request *req,
 					size_t expected_body_size);
 
+enum protocol_types smbd_smb2_protocol_dialect_match(const uint8_t *indyn,
+		                                     const int dialect_count,
+						     uint16_t *dialect);
 NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req);
 NTSTATUS smbd_smb2_request_process_sesssetup(struct smbd_smb2_request *req);
 NTSTATUS smbd_smb2_request_process_logoff(struct smbd_smb2_request *req);
diff --git a/source3/smbd/smb2_negprot.c b/source3/smbd/smb2_negprot.c
index 66434643782..5fa1fbbe008 100644
--- a/source3/smbd/smb2_negprot.c
+++ b/source3/smbd/smb2_negprot.c
@@ -82,61 +82,12 @@ void reply_smb20ff(struct smb_request *req, uint16_t choice)
 	reply_smb20xx(req, SMB2_DIALECT_REVISION_2FF);
 }
 
-NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
+enum protocol_types smbd_smb2_protocol_dialect_match(const uint8_t *indyn,
+				const int dialect_count,
+				uint16_t *dialect)
 {
-	NTSTATUS status;
-	const uint8_t *inbody;
-	const uint8_t *indyn = NULL;
-	DATA_BLOB outbody;
-	DATA_BLOB outdyn;
-	DATA_BLOB negprot_spnego_blob;
-	uint16_t security_offset;
-	DATA_BLOB security_buffer;
-	size_t expected_dyn_size = 0;
-	size_t c;
-	uint16_t security_mode;
-	uint16_t dialect_count;
-	uint16_t in_security_mode;
-	uint32_t in_capabilities;
-	DATA_BLOB in_guid_blob;
-	struct GUID in_guid;
-	uint16_t dialect = 0;
-	uint32_t capabilities;
-	DATA_BLOB out_guid_blob;
-	struct GUID out_guid;
+	size_t c = 0;
 	enum protocol_types protocol = PROTOCOL_NONE;
-	uint32_t max_limit;
-	uint32_t max_trans = lp_smb2_max_trans();
-	uint32_t max_read = lp_smb2_max_read();
-	uint32_t max_write = lp_smb2_max_write();
-	NTTIME now = timeval_to_nttime(&req->request_time);
-
-	status = smbd_smb2_request_verify_sizes(req, 0x24);
-	if (!NT_STATUS_IS_OK(status)) {
-		return smbd_smb2_request_error(req, status);
-	}
-	inbody = SMBD_SMB2_IN_BODY_PTR(req);
-
-	dialect_count = SVAL(inbody, 0x02);
-
-	in_security_mode = SVAL(inbody, 0x04);
-	in_capabilities = IVAL(inbody, 0x08);
-	in_guid_blob = data_blob_const(inbody + 0x0C, 16);
-
-	if (dialect_count == 0) {
-		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
-	}
-
-	status = GUID_from_ndr_blob(&in_guid_blob, &in_guid);
-	if (!NT_STATUS_IS_OK(status)) {
-		return smbd_smb2_request_error(req, status);
-	}
-
-	expected_dyn_size = dialect_count * 2;
-	if (SMBD_SMB2_IN_DYN_LEN(req) < expected_dyn_size) {
-		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
-	}
-	indyn = SMBD_SMB2_IN_DYN_PTR(req);
 
 	for (c=0; protocol == PROTOCOL_NONE && c < dialect_count; c++) {
 		if (lp_server_max_protocol() < PROTOCOL_SMB3_00) {
@@ -146,8 +97,8 @@ NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
 			break;
 		}
 
-		dialect = SVAL(indyn, c*2);
-		if (dialect == SMB3_DIALECT_REVISION_300) {
+		*dialect = SVAL(indyn, c*2);
+		if (*dialect == SMB3_DIALECT_REVISION_300) {
 			protocol = PROTOCOL_SMB3_00;
 			break;
 		}
@@ -161,8 +112,8 @@ NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
 			break;
 		}
 
-		dialect = SVAL(indyn, c*2);
-		if (dialect == SMB2_DIALECT_REVISION_224) {
+		*dialect = SVAL(indyn, c*2);
+		if (*dialect == SMB2_DIALECT_REVISION_224) {
 			protocol = PROTOCOL_SMB2_24;
 			break;
 		}
@@ -176,8 +127,8 @@ NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
 			break;
 		}
 
-		dialect = SVAL(indyn, c*2);
-		if (dialect == SMB2_DIALECT_REVISION_222) {
+		*dialect = SVAL(indyn, c*2);
+		if (*dialect == SMB2_DIALECT_REVISION_222) {
 			protocol = PROTOCOL_SMB2_22;
 			break;
 		}
@@ -191,8 +142,8 @@ NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
 			break;
 		}
 
-		dialect = SVAL(indyn, c*2);
-		if (dialect == SMB2_DIALECT_REVISION_210) {
+		*dialect = SVAL(indyn, c*2);
+		if (*dialect == SMB2_DIALECT_REVISION_210) {
 			protocol = PROTOCOL_SMB2_10;
 			break;
 		}
@@ -206,13 +157,76 @@ NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
 			break;
 		}
 
-		dialect = SVAL(indyn, c*2);
-		if (dialect == SMB2_DIALECT_REVISION_202) {
+		*dialect = SVAL(indyn, c*2);
+		if (*dialect == SMB2_DIALECT_REVISION_202) {
 			protocol = PROTOCOL_SMB2_02;
 			break;
 		}
 	}
 
+	return protocol;
+}
+
+NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
+{
+	NTSTATUS status;
+	const uint8_t *inbody;
+	const uint8_t *indyn = NULL;
+	DATA_BLOB outbody;
+	DATA_BLOB outdyn;
+	DATA_BLOB negprot_spnego_blob;
+	uint16_t security_offset;
+	DATA_BLOB security_buffer;
+	size_t expected_dyn_size = 0;
+	size_t c;
+	uint16_t security_mode;
+	uint16_t dialect_count;
+	uint16_t in_security_mode;
+	uint32_t in_capabilities;
+	DATA_BLOB in_guid_blob;
+	struct GUID in_guid;
+	uint16_t dialect = 0;
+	uint32_t capabilities;
+	DATA_BLOB out_guid_blob;
+	struct GUID out_guid;
+	enum protocol_types protocol = PROTOCOL_NONE;
+	uint32_t max_limit;
+	uint32_t max_trans = lp_smb2_max_trans();
+	uint32_t max_read = lp_smb2_max_read();
+	uint32_t max_write = lp_smb2_max_write();
+	NTTIME now = timeval_to_nttime(&req->request_time);
+
+	status = smbd_smb2_request_verify_sizes(req, 0x24);
+	if (!NT_STATUS_IS_OK(status)) {
+		return smbd_smb2_request_error(req, status);
+	}
+	inbody = SMBD_SMB2_IN_BODY_PTR(req);
+
+	dialect_count = SVAL(inbody, 0x02);
+
+	in_security_mode = SVAL(inbody, 0x04);
+	in_capabilities = IVAL(inbody, 0x08);
+	in_guid_blob = data_blob_const(inbody + 0x0C, 16);
+
+	if (dialect_count == 0) {
+		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
+	}
+
+	status = GUID_from_ndr_blob(&in_guid_blob, &in_guid);
+	if (!NT_STATUS_IS_OK(status)) {
+		return smbd_smb2_request_error(req, status);
+	}
+
+	expected_dyn_size = dialect_count * 2;
+	if (SMBD_SMB2_IN_DYN_LEN(req) < expected_dyn_size) {
+		return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
+	}
+	indyn = SMBD_SMB2_IN_DYN_PTR(req);
+
+	protocol = smbd_smb2_protocol_dialect_match(indyn,
+					dialect_count,
+					&dialect);
+
 	for (c=0; protocol == PROTOCOL_NONE && c < dialect_count; c++) {
 		if (lp_server_max_protocol() < PROTOCOL_SMB2_10) {
 			break;