add CDC-ECM/RNDIS/CDC-EEM network device class with example

lib/networking/dhserver.h

@@ -0,0 +1,63 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 by Sergey Fetisov <fsenok@gmail.com>
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * version: 1.0 demo (7.02.2015)
+ * brief:   tiny dhcp ipv4 server using lwip (pcb)
+ * ref:     https://lists.gnu.org/archive/html/lwip-users/2012-12/msg00016.html
+ */
+
+#ifndef DHSERVER_H
+#define DHSERVER_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include "lwip/err.h"
+#include "lwip/udp.h"
+#include "netif/etharp.h"
+
+typedef struct dhcp_entry
+{
+	uint8_t  mac[6];
+	uint8_t  addr[4];
+	uint8_t  subnet[4];
+	uint32_t lease;
+} dhcp_entry_t;
+
+typedef struct dhcp_config
+{
+	uint8_t       addr[4];
+	uint16_t      port;
+	uint8_t       dns[4];
+	const char   *domain;
+	int           num_entry;
+	dhcp_entry_t *entries;
+} dhcp_config_t;
+
+err_t dhserv_init(const dhcp_config_t *config);
+void dhserv_free(void);
+
+#endif /* DHSERVER_H */