Daiki Kato / DhcpServer_mbed-os

DhcpServer library for mbed-os.

Fork of DhcpServer by Daiki Kato

mbedボードをDHCPサーバとして使用するためのライブラリです。mbedボードとPCを直結する際などに使用してください。
このクラスは5つのIPアドレスを割り当てられることができます。
IPアドレスの上位3バイトはサーバーアドレスと同じで、下の1バイトは、10-14が割り当てられます。
例えば、サーバーアドレスが"192.168.0.1"の場合、IPアドレスは"192.168.0.10"～"192.168.0.14"が割り当てられます。

EthernetInterfaceでconnectを実行した後に、DhcpServerを使用してください。

    EthernetInterface eth;
    eth.init("192.168.0.1", "255.255.255.0", "192.168.0.1");
    eth.connect();
    DhcpServer dhcp_server(&eth, "HostName");


Library in Beta!

This library is in Beta.
このライブラリはβ版です。

DhcpServer.cpp

Committer:
dkato
Date:
2018-06-21
Revision:
4:ac6385f9f2db
Parent:
3:bdea854c0ec8

File content as of revision 4:ac6385f9f2db:

#include "mbed.h"
#include "rtos.h"
#include "TCPSocket.h"
#include "TCPServer.h"
#include "SocketAddress.h"
#include "UDPSocket.h"
#include "DhcpServer.h"

 /* DHCP message item offsets and length */
#define DHCP_SNAME_LEN    64U

/* DHCP message types */
#define DHCP_DISCOVER               1
#define DHCP_OFFER                  2
#define DHCP_REQUEST                3
#define DHCP_DECLINE                4
#define DHCP_ACK                    5
#define DHCP_NAK                    6
#define DHCP_RELEASE                7
#define DHCP_INFORM                 8

/* BootP options */
#define DHCP_OPTION_SUBNET_MASK     1 /* RFC 2132 3.3 */
#define DHCP_OPTION_ROUTER          3
#define DHCP_OPTION_DNS_SERVER      6

/* DHCP options */
#define DHCP_OPTION_LEASE_TIME      51 /* RFC 2132 9.2, time in seconds, in 4 bytes */

#define DHCP_OPTION_MESSAGE_TYPE    53 /* RFC 2132 9.6, important for DHCP */
#define DHCP_OPTION_MESSAGE_TYPE_LEN 1

#define DHCP_OPTION_SERVER_ID       54 /* RFC 2132 9.7, server IP address */


#define IP_ADDER_START (10)

#define OFS_XID        (4)
#define OFS_YIADDR     (16)
#define OFS_SIADDR     (20)
#define OFS_CHADDR     (28)
#define OFS_SNAME      (44)
#define OFS_COOKIE     (236)
#define OFS_OPTIONS    (240)

void DhcpServer::dhcp_process(void) {
    SocketAddress client;
    int cnt;
    int tbl_index;
    int option;
    nsapi_addr_t addr;
    const char mac_no_use[6] = {0, 0, 0, 0, 0, 0};

    dhcp_server.bind(67);
    option = 1;
    dhcp_server.setsockopt(0xfff, 0x0020, &option, sizeof(option));

    while (true) {
        int n = dhcp_server.recvfrom(&client, receivebuff, 500);
        if (n > 0) {
            addr.version = NSAPI_IPv4;
            addr.bytes[0] = 255;
            addr.bytes[1] = 255;
            addr.bytes[2] = 255;
            addr.bytes[3] = 255;
            client.set_addr(addr);
            client.set_port(68);

            sendbuff[OFS_XID + 0]    = receivebuff[OFS_XID + 0];
            sendbuff[OFS_XID + 1]    = receivebuff[OFS_XID + 1];
            sendbuff[OFS_XID + 2]    = receivebuff[OFS_XID + 2];
            sendbuff[OFS_XID + 3]    = receivebuff[OFS_XID + 3];

            tbl_index = -1;
            for (cnt = 0; cnt < CONNECT_NUM; cnt++) {
                if (memcmp(&receivebuff[OFS_CHADDR], chaddr_tbl[cnt], 6) == 0) {
                    tbl_index = cnt;
                    break;
                }
            }
            if (tbl_index == -1) {
                sendbuff[OFS_YIADDR + 0] = 0;
                sendbuff[OFS_YIADDR + 1] = 0;
                sendbuff[OFS_YIADDR + 2] = 0;
                sendbuff[OFS_YIADDR + 3] = 0;
            } else {
                sendbuff[OFS_YIADDR + 0] = sendbuff[OFS_SIADDR + 0];
                sendbuff[OFS_YIADDR + 1] = sendbuff[OFS_SIADDR + 1];
                sendbuff[OFS_YIADDR + 2] = sendbuff[OFS_SIADDR + 2];
                sendbuff[OFS_YIADDR + 3] = IP_ADDER_START + tbl_index;
            }

            sendbuff[OFS_CHADDR + 0] = receivebuff[OFS_CHADDR + 0];
            sendbuff[OFS_CHADDR + 1] = receivebuff[OFS_CHADDR + 1];
            sendbuff[OFS_CHADDR + 2] = receivebuff[OFS_CHADDR + 2];
            sendbuff[OFS_CHADDR + 3] = receivebuff[OFS_CHADDR + 3];
            sendbuff[OFS_CHADDR + 4] = receivebuff[OFS_CHADDR + 4];
            sendbuff[OFS_CHADDR + 5] = receivebuff[OFS_CHADDR + 5];

            if (receivebuff[OFS_OPTIONS + 2] == DHCP_DISCOVER) {
                sendbuff[OFS_OPTIONS + 2]  = DHCP_OFFER;
                if (tbl_index == -1) {
                    for (cnt = 0; cnt < CONNECT_NUM; cnt++) {
                        if (memcmp( chaddr_tbl[cnt], mac_no_use, 6) == 0) {
                            tbl_index = cnt;
                            break;
                        }
                    }
                }
                if (tbl_index != -1) {
                    chaddr_tbl[tbl_index][0]  = receivebuff[OFS_CHADDR + 0];
                    chaddr_tbl[tbl_index][1]  = receivebuff[OFS_CHADDR + 1];
                    chaddr_tbl[tbl_index][2]  = receivebuff[OFS_CHADDR + 2];
                    chaddr_tbl[tbl_index][3]  = receivebuff[OFS_CHADDR + 3];
                    chaddr_tbl[tbl_index][4]  = receivebuff[OFS_CHADDR + 4];
                    chaddr_tbl[tbl_index][5]  = receivebuff[OFS_CHADDR + 5];
                    sendbuff[OFS_YIADDR + 0] = sendbuff[OFS_SIADDR + 0];
                    sendbuff[OFS_YIADDR + 1] = sendbuff[OFS_SIADDR + 1];
                    sendbuff[OFS_YIADDR + 2] = sendbuff[OFS_SIADDR + 2];
                    sendbuff[OFS_YIADDR + 3] = IP_ADDER_START + tbl_index;
                }
                dhcp_server.sendto(client, sendbuff, 300);
            } else if (receivebuff[OFS_OPTIONS + 2] == DHCP_REQUEST) {
                if (tbl_index != -1) {
                    sendbuff[OFS_OPTIONS + 2]  = DHCP_ACK;
                } else {
                    sendbuff[OFS_OPTIONS + 2]  = DHCP_NAK;
                }
                dhcp_server.sendto(client, sendbuff, 300);
            } else if (receivebuff[OFS_OPTIONS + 2] == DHCP_RELEASE) {
                if (tbl_index != -1) {
                    memset(chaddr_tbl[tbl_index], 0, 6);
                }
            } else {
                // do nothing
            }
        }
    }
}

DhcpServer::DhcpServer(NetworkInterface *net, const char * name) :
 dhcp_server(net), dhcpThread(osPriorityNormal, (1024 * 8)) {
    uint32_t i;
    uint32_t len;
    uint32_t ofs;

    receivebuff = new char[500];
    sendbuff = new char[300];
    memset(sendbuff, 0, 300);
    memset(chaddr_tbl, 0, sizeof(chaddr_tbl));

    sscanf(net->get_ip_address(), "%d.%d.%d.%d", (int *)&sendbuff[OFS_SIADDR + 0], (int *)&sendbuff[OFS_SIADDR + 1],
     (int *)&sendbuff[OFS_SIADDR + 2], (int *)&sendbuff[OFS_SIADDR + 3]);

    len = strlen(name);
    for (i = 0; (i < len) && (i < DHCP_SNAME_LEN); i++) {
        sendbuff[OFS_SNAME + i] = name[i];
    }

    sendbuff[0] = 0x02;
    sendbuff[1] = 0x01;
    sendbuff[2] = 0x06;
    sendbuff[3] = 0x00;

    sendbuff[OFS_COOKIE + 0] = 0x63;
    sendbuff[OFS_COOKIE + 1] = 0x82;
    sendbuff[OFS_COOKIE + 2] = 0x53;
    sendbuff[OFS_COOKIE + 3] = 0x63;

    ofs = OFS_OPTIONS;
    sendbuff[ofs++] = DHCP_OPTION_MESSAGE_TYPE;
    sendbuff[ofs++] = DHCP_OPTION_MESSAGE_TYPE_LEN;
    sendbuff[ofs++] = 0;

    sendbuff[ofs++] = DHCP_OPTION_SERVER_ID;
    sendbuff[ofs++] = 0x04;
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 0];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 1];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 2];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 3];

    sendbuff[ofs++] = DHCP_OPTION_LEASE_TIME;
    sendbuff[ofs++] = 0x04;
    sendbuff[ofs++] = 0x00;
    sendbuff[ofs++] = 0x01;
    sendbuff[ofs++] = 0x4e;
    sendbuff[ofs++] = 0x20;

    sendbuff[ofs++] = DHCP_OPTION_SUBNET_MASK;
    sendbuff[ofs++] = 0x04;
    sendbuff[ofs++] = 0xff;
    sendbuff[ofs++] = 0xff;
    sendbuff[ofs++] = 0xff;
    sendbuff[ofs++] = 0xf0;

    sendbuff[ofs++] = DHCP_OPTION_ROUTER;
    sendbuff[ofs++] = 0x04;
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 0];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 1];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 2];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 3];

    sendbuff[ofs++] = DHCP_OPTION_DNS_SERVER;
    sendbuff[ofs++] = 0x04;
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 0];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 1];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 2];
    sendbuff[ofs++] = sendbuff[OFS_SIADDR + 3];

    sendbuff[ofs++] = 0xff;

    dhcpThread.start(callback(this, &DhcpServer::dhcp_process));
}

DhcpServer::~DhcpServer() {
    delete [] receivebuff;
    delete [] sendbuff;
}