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/*
* Copyright 2008, The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include <netinet/in.h>
#include "dhcpmsg.h"
static void *init_dhcp_msg(dhcp_msg *msg, int type, void *hwaddr, uint32_t xid)
{
uint8_t *x;
memset(msg, 0, sizeof(dhcp_msg));
msg->op = OP_BOOTREQUEST;
msg->htype = HTYPE_ETHER;
msg->hlen = 6;
msg->hops = 0;
msg->flags = htons(FLAGS_BROADCAST);
msg->xid = xid;
memcpy(msg->chaddr, hwaddr, 6);
x = msg->options;
*x++ = OPT_COOKIE1;
*x++ = OPT_COOKIE2;
*x++ = OPT_COOKIE3;
*x++ = OPT_COOKIE4;
*x++ = OPT_MESSAGE_TYPE;
*x++ = 1;
*x++ = type;
return x;
}
int init_dhcp_discover_msg(dhcp_msg *msg, void *hwaddr, uint32_t xid)
{
uint8_t *x;
x = init_dhcp_msg(msg, DHCPDISCOVER, hwaddr, xid);
*x++ = OPT_PARAMETER_LIST;
*x++ = 4;
*x++ = OPT_SUBNET_MASK;
*x++ = OPT_GATEWAY;
*x++ = OPT_DNS;
*x++ = OPT_BROADCAST_ADDR;
*x++ = OPT_END;
return DHCP_MSG_FIXED_SIZE + (x - msg->options);
}
int init_dhcp_request_msg(dhcp_msg *msg, void *hwaddr, uint32_t xid,
uint32_t ipaddr, uint32_t serveraddr)
{
uint8_t *x;
x = init_dhcp_msg(msg, DHCPREQUEST, hwaddr, xid);
*x++ = OPT_PARAMETER_LIST;
*x++ = 4;
*x++ = OPT_SUBNET_MASK;
*x++ = OPT_GATEWAY;
*x++ = OPT_DNS;
*x++ = OPT_BROADCAST_ADDR;
*x++ = OPT_REQUESTED_IP;
*x++ = 4;
memcpy(x, &ipaddr, 4);
x += 4;
*x++ = OPT_SERVER_ID;
*x++ = 4;
memcpy(x, &serveraddr, 4);
x += 4;
*x++ = OPT_END;
return DHCP_MSG_FIXED_SIZE + (x - msg->options);
}
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