src/libsystemd-dhcp/dhcp-client.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright (C) 2013 Intel Corporation. All rights reserved.
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <stdlib.h>
  21 #include <errno.h>
  22 #include <string.h>
  23 #include <stdio.h>
  24
  25 #include "util.h"
  26 #include "list.h"
  27
  28 #include "dhcp-protocol.h"
  29 #include "sd-dhcp-client.h"
  30
  31 struct sd_dhcp_client {
  32         DHCPState state;
  33         int index;
  34         uint8_t *req_opts;
  35         size_t req_opts_size;
  36         uint32_t last_addr;
  37 };
  38
  39 static const uint8_t default_req_opts[] = {
  40         DHCP_OPTION_SUBNET_MASK,
  41         DHCP_OPTION_ROUTER,
  42         DHCP_OPTION_HOST_NAME,
  43         DHCP_OPTION_DOMAIN_NAME,
  44         DHCP_OPTION_DOMAIN_NAME_SERVER,
  45         DHCP_OPTION_NTP_SERVER,
  46 };
  47
  48 int sd_dhcp_client_set_request_option(sd_dhcp_client *client, uint8_t option)
  49 {
  50         size_t i;
  51
  52         assert_return(client, -EINVAL);
  53         assert_return (client->state == DHCP_STATE_INIT, -EBUSY);
  54
  55         switch(option) {
  56         case DHCP_OPTION_PAD:
  57         case DHCP_OPTION_OVERLOAD:
  58         case DHCP_OPTION_MESSAGE_TYPE:
  59         case DHCP_OPTION_PARAMETER_REQUEST_LIST:
  60         case DHCP_OPTION_END:
  61                 return -EINVAL;
  62
  63         default:
  64                 break;
  65         }
  66
  67         for (i = 0; i < client->req_opts_size; i++)
  68                 if (client->req_opts[i] == option)
  69                         return -EEXIST;
  70
  71         if (!GREEDY_REALLOC(client->req_opts, client->req_opts_size,
  72                             client->req_opts_size + 1))
  73                 return -ENOMEM;
  74
  75         client->req_opts[client->req_opts_size - 1] = option;
  76
  77         return 0;
  78 }
  79
  80 int sd_dhcp_client_set_request_address(sd_dhcp_client *client,
  81                                        const struct in_addr *last_addr)
  82 {
  83         assert_return(client, -EINVAL);
  84         assert_return(client->state == DHCP_STATE_INIT, -EBUSY);
  85
  86         if (last_addr)
  87                 client->last_addr = last_addr->s_addr;
  88         else
  89                 client->last_addr = INADDR_ANY;
  90
  91         return 0;
  92 }
  93
  94 int sd_dhcp_client_set_index(sd_dhcp_client *client, int interface_index)
  95 {
  96         assert_return(client, -EINVAL);
  97         assert_return(client->state == DHCP_STATE_INIT, -EBUSY);
  98         assert_return(interface_index >= -1, -EINVAL);
  99
 100         client->index = interface_index;
 101
 102         return 0;
 103 }
 104
 105 sd_dhcp_client *sd_dhcp_client_new(void)
 106 {
 107         sd_dhcp_client *client;
 108
 109         client = new0(sd_dhcp_client, 1);
 110         if (!client)
 111                 return NULL;
 112
 113         client->state = DHCP_STATE_INIT;
 114         client->index = -1;
 115
 116         client->req_opts_size = ELEMENTSOF(default_req_opts);
 117
 118         client->req_opts = memdup(default_req_opts, client->req_opts_size);
 119         if (!client->req_opts) {
 120                 free(client);
 121                 return NULL;
 122         }
 123
 124         return client;
 125 }