libcli/smb: add smb2cli_conn_req_possible()

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
(cherry picked from commit 7efdc323d1a1abdae70bcafefe07b3cffcdb2521)

2 files changed, 23 insertions, 0 deletions

diff --git a/libcli/smb/smbXcli_base.c b/libcli/smb/smbXcli_base.c
index 028f1522d41..b502f4f7054 100644
--- a/libcli/smb/smbXcli_base.c
+++ b/libcli/smb/smbXcli_base.c
@@ -2452,6 +2452,28 @@ bool smbXcli_conn_has_async_calls(struct smbXcli_conn *conn)
 		|| (talloc_array_length(conn->pending) != 0));
 }
 
+bool smb2cli_conn_req_possible(struct smbXcli_conn *conn, uint32_t *max_dyn_len)
+{
+	uint16_t credits = 1;
+
+	if (conn->smb2.cur_credits == 0) {
+		if (max_dyn_len != NULL) {
+			*max_dyn_len = 0;
+		}
+		return false;
+	}
+
+	if (conn->smb2.server.capabilities & SMB2_CAP_LARGE_MTU) {
+		credits = conn->smb2.cur_credits;
+	}
+
+	if (max_dyn_len != NULL) {
+		*max_dyn_len = credits * 65536;
+	}
+
+	return true;
+}
+
 uint32_t smb2cli_conn_server_capabilities(struct smbXcli_conn *conn)
 {
 	return conn->smb2.server.capabilities;
diff --git a/libcli/smb/smbXcli_base.h b/libcli/smb/smbXcli_base.h
index 6b3156f42a0..a7cfcc32607 100644
--- a/libcli/smb/smbXcli_base.h
+++ b/libcli/smb/smbXcli_base.h
@@ -199,6 +199,7 @@ NTSTATUS smb1cli_echo_recv(struct tevent_req *req);
 NTSTATUS smb1cli_echo(struct smbXcli_conn *conn, uint32_t timeout_msec,
 		      uint16_t num_echos, DATA_BLOB data);
 
+bool smb2cli_conn_req_possible(struct smbXcli_conn *conn, uint32_t *max_dyn_len);
 uint32_t smb2cli_conn_server_capabilities(struct smbXcli_conn *conn);
 uint16_t smb2cli_conn_server_security_mode(struct smbXcli_conn *conn);
 uint32_t smb2cli_conn_max_trans_size(struct smbXcli_conn *conn);