rtt-f030/components/net/lwip_dhcpd/dhcp_server.c

432 lines
14 KiB
C

/*
* File : dhcp_server.c
* A simple DHCP server implementation
*
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2013-2015, Shanghai Real-Thread Technology Co., Ltd
* http://www.rt-thread.com
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Change Logs:
* Date Author Notes
* 2013-01-30 aozima the first version
* 2013-08-08 aozima support different network segments.
* 2015-01-30 bernard release to RT-Thread RTOS.
*/
#include <stdio.h>
#include <stdint.h>
#include <rtthread.h>
#include <lwip/opt.h>
#include <lwip/sockets.h>
#include <lwip/inet_chksum.h>
#include <netif/etharp.h>
#include <netif/ethernetif.h>
#include <lwip/ip.h>
#include <lwip/init.h>
#if (LWIP_VERSION) >= 0x02000000U
#include <lwip/prot/dhcp.h>
#endif
/* DHCP server option */
/* allocated client ip range */
#ifndef DHCPD_CLIENT_IP_MIN
#define DHCPD_CLIENT_IP_MIN 2
#endif
#ifndef DHCPD_CLIENT_IP_MAX
#define DHCPD_CLIENT_IP_MAX 254
#endif
/* the DHCP server address */
#ifndef DHCPD_SERVER_IPADDR0
#define DHCPD_SERVER_IPADDR0 192UL
#define DHCPD_SERVER_IPADDR1 168UL
#define DHCPD_SERVER_IPADDR2 169UL
#define DHCPD_SERVER_IPADDR3 1UL
#endif
//#define DHCP_DEBUG_PRINTF
#ifdef DHCP_DEBUG_PRINTF
#define DEBUG_PRINTF rt_kprintf("[DHCP] "); rt_kprintf
#else
#define DEBUG_PRINTF(...)
#endif /* DHCP_DEBUG_PRINTF */
/* we need some routines in the DHCP of lwIP */
#undef LWIP_DHCP
#define LWIP_DHCP 1
#include <lwip/dhcp.h>
/* buffer size for receive DHCP packet */
#define BUFSZ 1024
static uint8_t next_client_ip = DHCPD_CLIENT_IP_MIN;
static rt_err_t _low_level_dhcp_send(struct netif *netif,
const void *buffer,
rt_size_t size)
{
struct pbuf *p;
struct eth_hdr *ethhdr;
struct ip_hdr *iphdr;
struct udp_hdr *udphdr;
p = pbuf_alloc(PBUF_LINK,
SIZEOF_ETH_HDR + sizeof(struct ip_hdr)
+ sizeof(struct udp_hdr) + size,
PBUF_RAM);
if (p == RT_NULL) return -RT_ENOMEM;
ethhdr = (struct eth_hdr *)p->payload;
iphdr = (struct ip_hdr *)((char *)ethhdr + SIZEOF_ETH_HDR);
udphdr = (struct udp_hdr *)((char *)iphdr + sizeof(struct ip_hdr));
ETHADDR32_COPY(&ethhdr->dest, (struct eth_addr *)&ethbroadcast);
ETHADDR16_COPY(&ethhdr->src, netif->hwaddr);
ethhdr->type = PP_HTONS(ETHTYPE_IP);
iphdr->src.addr = 0x00000000; /* src: 0.0.0.0 */
iphdr->dest.addr = 0xFFFFFFFF; /* src: 255.255.255.255 */
IPH_VHL_SET(iphdr, 4, IP_HLEN / 4);
IPH_TOS_SET(iphdr, 0x00);
IPH_LEN_SET(iphdr, htons(IP_HLEN + sizeof(struct udp_hdr) + size));
IPH_ID_SET(iphdr, htons(2));
IPH_OFFSET_SET(iphdr, 0);
IPH_TTL_SET(iphdr, 255);
IPH_PROTO_SET(iphdr, IP_PROTO_UDP);
IPH_CHKSUM_SET(iphdr, 0);
IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
udphdr->src = htons(DHCP_SERVER_PORT);
udphdr->dest = htons(DHCP_CLIENT_PORT);
udphdr->len = htons(sizeof(struct udp_hdr) + size);
udphdr->chksum = 0;
memcpy((char *)udphdr + sizeof(struct udp_hdr),
buffer, size);
netif->linkoutput(netif, p);
pbuf_free(p);
return RT_EOK;
}
static void dhcpd_thread_entry(void *parameter)
{
struct netif *netif = RT_NULL;
int sock;
int bytes_read;
char *recv_data;
rt_uint32_t addr_len;
struct sockaddr_in server_addr, client_addr;
struct dhcp_msg *msg;
int optval = 1;
/* get ethernet interface. */
netif = (struct netif *) parameter;
RT_ASSERT(netif != RT_NULL);
/* our DHCP server information */
DEBUG_PRINTF("DHCP server IP: %d.%d.%d.%d client IP: %d.%d.%d.%d-%d\n",
DHCPD_SERVER_IPADDR0, DHCPD_SERVER_IPADDR1,
DHCPD_SERVER_IPADDR2, DHCPD_SERVER_IPADDR3,
DHCPD_SERVER_IPADDR0, DHCPD_SERVER_IPADDR1,
DHCPD_SERVER_IPADDR2, DHCPD_CLIENT_IP_MIN, DHCPD_CLIENT_IP_MAX);
/* allocate buffer for receive */
recv_data = rt_malloc(BUFSZ);
if (recv_data == RT_NULL)
{
/* No memory */
DEBUG_PRINTF("Out of memory\n");
return;
}
/* create a socket with UDP */
if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
{
DEBUG_PRINTF("create socket failed, errno = %d\n", errno);
rt_free(recv_data);
return;
}
/* set to receive broadcast packet */
setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &optval, sizeof(optval));
/* initialize server address */
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(DHCP_SERVER_PORT);
server_addr.sin_addr.s_addr = INADDR_ANY;
rt_memset(&(server_addr.sin_zero), 0, sizeof(server_addr.sin_zero));
/* bind socket to the server address */
if (bind(sock, (struct sockaddr *)&server_addr,
sizeof(struct sockaddr)) == -1)
{
/* bind failed. */
DEBUG_PRINTF("bind server address failed, errno=%d\n", errno);
rt_free(recv_data);
return;
}
addr_len = sizeof(struct sockaddr);
DEBUG_PRINTF("DHCP server listen on port %d...\n", DHCP_SERVER_PORT);
while (1)
{
bytes_read = recvfrom(sock, recv_data, BUFSZ - 1, 0,
(struct sockaddr *)&client_addr, &addr_len);
if (bytes_read < DHCP_MSG_LEN)
{
DEBUG_PRINTF("packet too short, wait for next!\n");
continue;
}
msg = (struct dhcp_msg *)recv_data;
/* check message type to make sure we can handle it */
if ((msg->op != DHCP_BOOTREQUEST) || (msg->cookie != PP_HTONL(DHCP_MAGIC_COOKIE)))
{
continue;
}
/* handler. */
{
uint8_t *dhcp_opt;
uint8_t option;
uint8_t length;
uint8_t message_type = 0;
uint8_t finished = 0;
uint32_t request_ip = 0;
dhcp_opt = (uint8_t *)msg + DHCP_OPTIONS_OFS;
while (finished == 0)
{
option = *dhcp_opt;
length = *(dhcp_opt + 1);
switch (option)
{
case DHCP_OPTION_REQUESTED_IP:
request_ip = *(dhcp_opt + 2) << 24 | *(dhcp_opt + 3) << 16
| *(dhcp_opt + 4) << 8 | *(dhcp_opt + 5);
break;
case DHCP_OPTION_END:
finished = 1;
break;
case DHCP_OPTION_MESSAGE_TYPE:
message_type = *(dhcp_opt + 2);
break;
default:
break;
} /* switch(option) */
dhcp_opt += (2 + length);
}
/* reply. */
dhcp_opt = (uint8_t *)msg + DHCP_OPTIONS_OFS;
/* check. */
if (request_ip)
{
uint32_t client_ip = DHCPD_SERVER_IPADDR0 << 24 | DHCPD_SERVER_IPADDR1 << 16
| DHCPD_SERVER_IPADDR2 << 8 | (next_client_ip);
if (request_ip != client_ip)
{
*dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE;
*dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE_LEN;
*dhcp_opt++ = DHCP_NAK;
*dhcp_opt++ = DHCP_OPTION_END;
DEBUG_PRINTF("requested IP invalid, reply DHCP_NAK\n");
if (netif != RT_NULL)
{
int send_byte = (dhcp_opt - (uint8_t *)msg);
_low_level_dhcp_send(netif, msg, send_byte);
DEBUG_PRINTF("DHCP server send %d byte\n", send_byte);
}
next_client_ip++;
if (next_client_ip > DHCPD_CLIENT_IP_MAX)
next_client_ip = DHCPD_CLIENT_IP_MIN;
continue;
}
}
if (message_type == DHCP_DISCOVER)
{
DEBUG_PRINTF("request DHCP_DISCOVER\n");
DEBUG_PRINTF("reply DHCP_OFFER\n");
// DHCP_OPTION_MESSAGE_TYPE
*dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE;
*dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE_LEN;
*dhcp_opt++ = DHCP_OFFER;
// DHCP_OPTION_SERVER_ID
*dhcp_opt++ = DHCP_OPTION_SERVER_ID;
*dhcp_opt++ = 4;
*dhcp_opt++ = DHCPD_SERVER_IPADDR0;
*dhcp_opt++ = DHCPD_SERVER_IPADDR1;
*dhcp_opt++ = DHCPD_SERVER_IPADDR2;
*dhcp_opt++ = DHCPD_SERVER_IPADDR3;
// DHCP_OPTION_LEASE_TIME
*dhcp_opt++ = DHCP_OPTION_LEASE_TIME;
*dhcp_opt++ = 4;
*dhcp_opt++ = 0x00;
*dhcp_opt++ = 0x01;
*dhcp_opt++ = 0x51;
*dhcp_opt++ = 0x80;
}
else if (message_type == DHCP_REQUEST)
{
DEBUG_PRINTF("request DHCP_REQUEST\n");
DEBUG_PRINTF("reply DHCP_ACK\n");
// DHCP_OPTION_MESSAGE_TYPE
*dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE;
*dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE_LEN;
*dhcp_opt++ = DHCP_ACK;
// DHCP_OPTION_SERVER_ID
*dhcp_opt++ = DHCP_OPTION_SERVER_ID;
*dhcp_opt++ = 4;
*dhcp_opt++ = DHCPD_SERVER_IPADDR0;
*dhcp_opt++ = DHCPD_SERVER_IPADDR1;
*dhcp_opt++ = DHCPD_SERVER_IPADDR2;
*dhcp_opt++ = DHCPD_SERVER_IPADDR3;
// DHCP_OPTION_SUBNET_MASK
*dhcp_opt++ = DHCP_OPTION_SUBNET_MASK;
*dhcp_opt++ = 4;
*dhcp_opt++ = 0xFF;
*dhcp_opt++ = 0xFF;
*dhcp_opt++ = 0xFF;
*dhcp_opt++ = 0x00;
#ifdef DHCPD_USING_ROUTER
// DHCP_OPTION_ROUTER
*dhcp_opt++ = DHCP_OPTION_ROUTER;
*dhcp_opt++ = 4;
*dhcp_opt++ = DHCPD_SERVER_IPADDR0;
*dhcp_opt++ = DHCPD_SERVER_IPADDR1;
*dhcp_opt++ = DHCPD_SERVER_IPADDR2;
*dhcp_opt++ = 1;
#endif
// DHCP_OPTION_DNS_SERVER, use the default DNS server address in lwIP
*dhcp_opt++ = DHCP_OPTION_DNS_SERVER;
*dhcp_opt++ = 4;
*dhcp_opt++ = 208;
*dhcp_opt++ = 67;
*dhcp_opt++ = 222;
*dhcp_opt++ = 222;
// DHCP_OPTION_LEASE_TIME
*dhcp_opt++ = DHCP_OPTION_LEASE_TIME;
*dhcp_opt++ = 4;
*dhcp_opt++ = 0x00;
*dhcp_opt++ = 0x01;
*dhcp_opt++ = 0x51;
*dhcp_opt++ = 0x80;
}
else
{
DEBUG_PRINTF("un handle message:%d\n", message_type);
}
// append DHCP_OPTION_END
*dhcp_opt++ = DHCP_OPTION_END;
/* send reply. */
if ((message_type == DHCP_DISCOVER) || (message_type == DHCP_REQUEST))
{
msg->op = DHCP_BOOTREPLY;
IP4_ADDR(&msg->yiaddr,
DHCPD_SERVER_IPADDR0, DHCPD_SERVER_IPADDR1,
DHCPD_SERVER_IPADDR2, next_client_ip);
client_addr.sin_addr.s_addr = INADDR_BROADCAST;
if (netif != RT_NULL)
{
int send_byte = (dhcp_opt - (uint8_t *)msg);
_low_level_dhcp_send(netif, msg, send_byte);
DEBUG_PRINTF("DHCP server send %d byte\n", send_byte);
}
}
} /* handler. */
}
}
void dhcpd_start(char *netif_name)
{
rt_thread_t thread;
struct netif *netif = netif_list;
if (strlen(netif_name) > sizeof(netif->name))
{
rt_kprintf("network interface name too long!\r\n");
return;
}
while (netif != RT_NULL)
{
if (strncmp(netif_name, netif->name, sizeof(netif->name)) == 0)
break;
netif = netif->next;
if (netif == RT_NULL)
{
rt_kprintf("network interface: %s not found!\r\n", netif_name);
return;
}
}
if (1)
{
extern void set_if(char *netif_name, char *ip_addr, char *gw_addr, char *nm_addr);
char ip_str[4 * 4 + 1];
dhcp_stop(netif);
sprintf(ip_str, "%d.%d.%d.%d", DHCPD_SERVER_IPADDR0, DHCPD_SERVER_IPADDR1, DHCPD_SERVER_IPADDR2, DHCPD_SERVER_IPADDR3);
set_if(netif_name, ip_str, "0.0.0.0", "255.255.255.0");
netif_set_up(netif);
}
thread = rt_thread_create("dhcpd",
dhcpd_thread_entry, netif,
1024,
RT_THREAD_PRIORITY_MAX - 3,
2);
if (thread != RT_NULL)
{
rt_thread_startup(thread);
}
}