src/libsystemd-network/dhcp-protocol.h

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2 #pragma once
   3
   4 /***
   5   Copyright © 2013 Intel Corporation. All rights reserved.
   6 ***/
   7
   8 #include <netinet/ip.h>
   9 #include <netinet/udp.h>
  10
  11 #include "sd-dhcp-protocol.h"
  12
  13 #include "forward.h"
  14 #include "sparse-endian.h"
  15 #include "time-util.h"
  16
  17 /* RFC 8925 - IPv6-Only Preferred Option for DHCPv4 3.4.
  18  * MIN_V6ONLY_WAIT: The lower boundary for V6ONLY_WAIT. Value: 300 seconds */
  19 #define MIN_V6ONLY_WAIT_USEC (300U * USEC_PER_SEC)
  20
  21 #define DHCP_MESSAGE_HEADER_DEFINITION \
  22         uint8_t op;                    \
  23         uint8_t htype;                 \
  24         uint8_t hlen;                  \
  25         uint8_t hops;                  \
  26         be32_t xid;                    \
  27         be16_t secs;                   \
  28         be16_t flags;                  \
  29         be32_t ciaddr;                 \
  30         be32_t yiaddr;                 \
  31         be32_t siaddr;                 \
  32         be32_t giaddr;                 \
  33         uint8_t chaddr[16];            \
  34         uint8_t sname[64];             \
  35         uint8_t file[128];             \
  36         be32_t magic;
  37
  38 struct DHCPMessage {
  39         DHCP_MESSAGE_HEADER_DEFINITION;
  40         uint8_t options[];
  41 } _packed_;
  42
  43 typedef struct DHCPMessage DHCPMessage;
  44
  45 struct DHCPPacket {
  46         struct iphdr ip;
  47         struct udphdr udp;
  48         DHCPMessage dhcp;
  49 } _packed_;
  50
  51 typedef struct DHCPPacket DHCPPacket;
  52
  53 #define DHCP_IP_SIZE            (int32_t)(sizeof(struct iphdr))
  54 #define DHCP_IP_UDP_SIZE        (int32_t)(sizeof(struct udphdr) + DHCP_IP_SIZE)
  55 #define DHCP_HEADER_SIZE        (int32_t)(sizeof(DHCPMessage))
  56 #define DHCP_MIN_MESSAGE_SIZE   576 /* the minimum internet hosts must be able to receive, see RFC 2132 Section 9.10 */
  57 #define DHCP_MIN_OPTIONS_SIZE   (DHCP_MIN_MESSAGE_SIZE - DHCP_HEADER_SIZE)
  58 #define DHCP_MIN_PACKET_SIZE    (DHCP_MIN_MESSAGE_SIZE + DHCP_IP_UDP_SIZE)
  59 #define DHCP_MAGIC_COOKIE       (uint32_t)(0x63825363)
  60
  61 enum {
  62         DHCP_PORT_SERVER                        = 67,
  63         DHCP_PORT_CLIENT                        = 68,
  64 };
  65
  66 enum {
  67         BOOTREQUEST                             = 1,
  68         BOOTREPLY                               = 2,
  69 };
  70
  71 enum {
  72         DHCP_DISCOVER                           = 1,  /* [RFC2132] */
  73         DHCP_OFFER                              = 2,  /* [RFC2132] */
  74         DHCP_REQUEST                            = 3,  /* [RFC2132] */
  75         DHCP_DECLINE                            = 4,  /* [RFC2132] */
  76         DHCP_ACK                                = 5,  /* [RFC2132] */
  77         DHCP_NAK                                = 6,  /* [RFC2132] */
  78         DHCP_RELEASE                            = 7,  /* [RFC2132] */
  79         DHCP_INFORM                             = 8,  /* [RFC2132] */
  80         DHCP_FORCERENEW                         = 9,  /* [RFC3203] */
  81         DHCPLEASEQUERY                          = 10, /* [RFC4388] */
  82         DHCPLEASEUNASSIGNED                     = 11, /* [RFC4388] */
  83         DHCPLEASEUNKNOWN                        = 12, /* [RFC4388] */
  84         DHCPLEASEACTIVE                         = 13, /* [RFC4388] */
  85         DHCPBULKLEASEQUERY                      = 14, /* [RFC6926] */
  86         DHCPLEASEQUERYDONE                      = 15, /* [RFC6926] */
  87         DHCPACTIVELEASEQUERY                    = 16, /* [RFC7724] */
  88         DHCPLEASEQUERYSTATUS                    = 17, /* [RFC7724] */
  89         DHCPTLS                                 = 18, /* [RFC7724] */
  90 };
  91
  92 enum {
  93         DHCP_OVERLOAD_FILE                      = 1,
  94         DHCP_OVERLOAD_SNAME                     = 2,
  95 };
  96
  97 #define DHCP_MAX_FQDN_LENGTH 255
  98
  99 enum {
 100         DHCP_FQDN_FLAG_S = (1 << 0),
 101         DHCP_FQDN_FLAG_O = (1 << 1),
 102         DHCP_FQDN_FLAG_E = (1 << 2),
 103         DHCP_FQDN_FLAG_N = (1 << 3),
 104 };