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/*
*
* DHCP client library with GLib integration
*
* Copyright (C) 2009-2010 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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 St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <netinet/udp.h>
#include <netinet/ip.h>
#include <glib.h>
#include "gdhcp.h"
#define dhcp_get_unaligned(ptr) \
({ \
struct __attribute__((packed)) { \
typeof(*(ptr)) __v; \
} *__p = (void *) (ptr); \
__p->__v; \
})
#define dhcp_put_unaligned(val, ptr) \
do { \
struct __attribute__((packed)) { \
typeof(*(ptr)) __v; \
} *__p = (void *) (ptr); \
__p->__v = (val); \
} while (0)
#define CLIENT_PORT 68
#define SERVER_PORT 67
#define EXTEND_FOR_BUGGY_SERVERS 80
static const uint8_t MAC_BCAST_ADDR[ETH_ALEN] __attribute__((aligned(2))) = {
0xff, 0xff, 0xff, 0xff, 0xff, 0xff
};
static const uint8_t MAC_ANY_ADDR[ETH_ALEN] __attribute__((aligned(2))) = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* DHCP packet */
#define DHCP_MAGIC 0x63825363
#define DHCP_OPTIONS_BUFSIZE 308
#define BOOTREQUEST 1
#define BOOTREPLY 2
#define BROADCAST_FLAG 0x8000
/* See RFC 2131 */
struct dhcp_packet {
uint8_t op;
uint8_t htype;
uint8_t hlen;
uint8_t hops;
uint32_t xid;
uint16_t secs;
uint16_t flags;
uint32_t ciaddr;
uint32_t yiaddr;
uint32_t siaddr_nip;
uint32_t gateway_nip;
uint8_t chaddr[16];
uint8_t sname[64];
uint8_t file[128];
uint32_t cookie;
uint8_t options[DHCP_OPTIONS_BUFSIZE + EXTEND_FOR_BUGGY_SERVERS];
} __attribute__((packed));
struct ip_udp_dhcp_packet {
struct iphdr ip;
struct udphdr udp;
struct dhcp_packet data;
} __attribute__((packed));
/* See RFC 2132 */
#define DHCP_PADDING 0x00
#define DHCP_SUBNET 0x01
#define DHCP_ROUTER 0x03
#define DHCP_TIME_SERVER 0x04
#define DHCP_NAME_SERVER 0x05
#define DHCP_DNS_SERVER 0x06
#define DHCP_HOST_NAME 0x0c
#define DHCP_DOMAIN_NAME 0x0f
#define DHCP_NTP_SERVER 0x2a
#define DHCP_REQUESTED_IP 0x32
#define DHCP_LEASE_TIME 0x33
#define DHCP_OPTION_OVERLOAD 0x34
#define DHCP_MESSAGE_TYPE 0x35
#define DHCP_SERVER_ID 0x36
#define DHCP_PARAM_REQ 0x37
#define DHCP_ERR_MESSAGE 0x38
#define DHCP_MAX_SIZE 0x39
#define DHCP_VENDOR 0x3c
#define DHCP_CLIENT_ID 0x3d
#define DHCP_END 0xff
#define OPT_CODE 0
#define OPT_LEN 1
#define OPT_DATA 2
#define OPTION_FIELD 0
#define FILE_FIELD 1
#define SNAME_FIELD 2
/* DHCP_MESSAGE_TYPE values */
#define DHCPDISCOVER 1
#define DHCPOFFER 2
#define DHCPREQUEST 3
#define DHCPDECLINE 4
#define DHCPACK 5
#define DHCPNAK 6
#define DHCPRELEASE 7
#define DHCPINFORM 8
#define DHCP_MINTYPE DHCPDISCOVER
#define DHCP_MAXTYPE DHCPINFORM
typedef enum {
OPTION_UNKNOWN,
OPTION_IP,
OPTION_STRING,
OPTION_U8,
OPTION_U16,
OPTION_U32,
OPTION_TYPE_MASK = 0x0f,
OPTION_LIST = 0x10,
} GDHCPOptionType;
typedef struct dhcp_option {
GDHCPOptionType type;
uint8_t code;
} DHCPOption;
/* Length of the option types in binary form */
static const uint8_t dhcp_option_lengths[] = {
[OPTION_IP] = 4,
[OPTION_STRING] = 1,
[OPTION_U8] = 1,
[OPTION_U16] = 2,
[OPTION_U32] = 4,
};
uint8_t *dhcp_get_option(struct dhcp_packet *packet, int code);
int dhcp_end_option(uint8_t *optionptr);
void dhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt);
void dhcp_add_simple_option(struct dhcp_packet *packet,
uint8_t code, uint32_t data);
GDHCPOptionType dhcp_get_code_type(uint8_t code);
uint16_t dhcp_checksum(void *addr, int count);
void dhcp_init_header(struct dhcp_packet *packet, char type);
int dhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt,
uint32_t source_ip, int source_port,
uint32_t dest_ip, int dest_port,
const uint8_t *dest_arp, int ifindex);
int dhcp_send_kernel_packet(struct dhcp_packet *dhcp_pkt,
uint32_t source_ip, int source_port,
uint32_t dest_ip, int dest_port);
int dhcp_l3_socket(int port, const char *interface);
int dhcp_recv_l3_packet(struct dhcp_packet *packet, int fd);
char *get_interface_name(int index);
gboolean interface_is_up(int index);
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