1 /******************************************************************************
2 * Copyright (c) 2013 IBM Corporation
3 * All rights reserved.
4 * This program and the accompanying materials
5 * are made available under the terms of the BSD License
6 * which accompanies this distribution, and is available at
7 * http://www.opensource.org/licenses/bsd-license.php
8 *
9 * Contributors:
10 * IBM Corporation - initial implementation
11 *****************************************************************************/
12
13 #include <string.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <stdint.h>
17 #include <sys/socket.h>
18 #include <time.h>
19 #include "ethernet.h"
20 #include "ipv6.h"
21 #include "udp.h"
22 #include "dhcpv6.h"
23 #include "tftp.h"
24 #include "dns.h"
25
26 static uint8_t tid[3];
27 static uint32_t dhcpv6_state = -1;
28 static filename_ip_t *my_fn_ip;
29
30 static struct ip6addr_list_entry all_dhcpv6_ll; /* All DHCPv6 servers address */
31
32 void
dhcpv6_generate_transaction_id(void)33 dhcpv6_generate_transaction_id(void)
34 {
35 /* As per RFC 3315 transaction IDs should be generated randomly */
36 tid[0] = rand();
37 tid[1] = rand();
38 tid[2] = rand();
39 }
40
41 static void
send_info_request(int fd)42 send_info_request(int fd)
43 {
44 uint8_t ether_packet[ETH_MTU_SIZE];
45 uint32_t payload_length;
46 struct dhcp_message_header *dhcph;
47
48 memset(ether_packet, 0, ETH_MTU_SIZE);
49
50 /* Get an IPv6 packet */
51 payload_length = sizeof(struct udphdr) + sizeof(struct dhcp_message_header);
52 fill_ip6hdr (ether_packet + sizeof(struct ethhdr),
53 payload_length, IPTYPE_UDP,
54 get_ipv6_address(), &(all_dhcpv6_ll.addr));
55 fill_udphdr ( ether_packet + sizeof(struct ethhdr) + sizeof(struct ip6hdr),
56 payload_length, DHCP_CLIENT_PORT, DHCP_SERVER_PORT);
57 dhcph = (struct dhcp_message_header *) (ether_packet +
58 sizeof(struct ethhdr) +
59 sizeof(struct ip6hdr) +
60 sizeof(struct udphdr));
61
62 /* Fill in DHCPv6 data */
63 dhcph->type = DHCP_INFORMATION_REQUEST;
64 memcpy( &(dhcph->transaction_id), &tid, 3);
65 dhcph->option.client_id.code = DHCPV6_OPTION_CLIENTID;
66 dhcph->option.client_id.length = 10;
67 dhcph->option.client_id.duid_type = DUID_LL;
68 dhcph->option.client_id.hardware_type = 1;
69 memcpy( &(dhcph->option.client_id.mac),
70 get_mac_address(), 6);
71 dhcph->option.el_time.code = DHCPV6_OPTION_ELAPSED_TIME;
72 dhcph->option.el_time.length = 2;
73 dhcph->option.el_time.time = 0x190; /* 4000 ms */
74 dhcph->option.option_request_option.code = DHCPV6_OPTION_ORO;
75 dhcph->option.option_request_option.length = DHCPV6_OPTREQUEST_NUMOPTS * 2;
76 dhcph->option.option_request_option.option_code[0] = DHCPV6_OPTION_DNS_SERVERS;
77 dhcph->option.option_request_option.option_code[1] = DHCPV6_OPTION_DOMAIN_LIST;
78 dhcph->option.option_request_option.option_code[2] = DHCPV6_OPTION_BOOT_URL;
79
80 send_ipv6(fd, ether_packet + sizeof(struct ethhdr),
81 sizeof(struct ip6hdr) + sizeof(struct udphdr)
82 + sizeof(struct dhcp_message_header));
83 }
84
85 static int32_t
dhcpv6_attempt(int fd)86 dhcpv6_attempt(int fd)
87 {
88 int sec;
89
90 // Send information request
91 send_info_request(fd);
92
93 dhcpv6_state = DHCPV6_STATE_SELECT;
94
95 // setting up a timer with a timeout of two seconds
96 for (sec = 0; sec < 2; sec++) {
97 set_timer(TICKS_SEC);
98 do {
99 receive_ether(fd);
100
101 // Wait until client will switch to Final state or Timeout occurs
102 switch (dhcpv6_state) {
103 case DHCP_STATUSCODE_SUCCESS:
104 return 1;
105 case DHCP_STATUSCODE_UNSPECFAIL: //FIXME
106 return 0;
107 }
108 } while (get_timer() > 0);
109 }
110
111 // timeout
112 return 0;
113 }
114
115 int32_t
dhcpv6(char * ret_buffer,void * fn_ip)116 dhcpv6 ( char *ret_buffer, void *fn_ip)
117 {
118 int fd;
119
120 all_dhcpv6_ll.addr.part.prefix = 0xff02000000000000ULL;
121 all_dhcpv6_ll.addr.part.interface_id = 0x10002ULL;
122
123 my_fn_ip = (filename_ip_t *) fn_ip;
124 fd = my_fn_ip->fd;
125
126 if( !dhcpv6_attempt(fd)) {
127 return -1;
128 }
129
130 return 0;
131 }
132
dhcp6_process_options(uint8_t * option,int32_t option_length)133 static void dhcp6_process_options (uint8_t *option, int32_t option_length)
134 {
135 struct dhcp_boot_url *option_boot_url;
136 struct client_identifier *option_clientid;
137 struct server_identifier *option_serverid;
138 struct dhcp_dns *option_dns;
139 struct dhcp_dns_list *option_dns_list;
140 struct dhcp6_gen_option *option_gen;
141 char buffer[256];
142
143 while (option_length > 0) {
144 switch ((uint16_t) *(option+1)) {
145 case DHCPV6_OPTION_CLIENTID:
146 option_clientid = (struct client_identifier *) option;
147 option = option + option_clientid->length + 4;
148 option_length = option_length - option_clientid->length - 4;
149 break;
150 case DHCPV6_OPTION_SERVERID:
151 option_serverid = (struct server_identifier *) option;
152 option = option + option_serverid->length + 4;
153 option_length = option_length - option_serverid->length - 4;
154 break;
155 case DHCPV6_OPTION_DNS_SERVERS:
156 option_dns = (struct dhcp_dns *) option;
157 option = option + option_dns->length + 4;
158 option_length = option_length - option_dns->length - 4;
159 memcpy( &(my_fn_ip->dns_ip6),
160 option_dns->p_ip6,
161 IPV6_ADDR_LENGTH);
162 dns_init(0, option_dns->p_ip6, 6);
163 break;
164 case DHCPV6_OPTION_DOMAIN_LIST:
165 option_dns_list = (struct dhcp_dns_list *) option;
166 option = option + option_dns_list->length + 4;
167 option_length = option_length - option_dns_list->length - 4;
168 break;
169 case DHCPV6_OPTION_BOOT_URL:
170 option_boot_url = (struct dhcp_boot_url *) option;
171 option = option + option_boot_url->length + 4;
172 option_length = option_length - option_boot_url->length - 4;
173 strncpy((char *)buffer,
174 (const char *)option_boot_url->url,
175 (size_t)option_boot_url->length);
176 buffer[option_boot_url->length] = 0;
177 if (parse_tftp_args(buffer,
178 (char *)my_fn_ip->server_ip6.addr,
179 my_fn_ip->filename, my_fn_ip->fd,
180 option_boot_url->length) == -1)
181 return;
182 break;
183 default:
184 option_gen = (struct dhcp6_gen_option *) option;
185 option = option + option_gen->length + 4;
186 option_length = option_length - option_gen->length - 4;
187 }
188 }
189 }
190
191 uint32_t
handle_dhcpv6(uint8_t * packet,int32_t packetsize)192 handle_dhcpv6(uint8_t * packet, int32_t packetsize)
193 {
194
195 uint8_t *first_option;
196 int32_t option_length;
197 struct dhcp_message_reply *reply;
198 reply = (struct dhcp_message_reply *) packet;
199
200 if (memcmp(reply->transaction_id, tid, 3))
201 return -1; /* Wrong transaction ID */
202
203 if (reply->type == 7)
204 dhcpv6_state = DHCP_STATUSCODE_SUCCESS;
205
206 first_option = packet + 4;
207 option_length = packet + packetsize - first_option;
208 dhcp6_process_options(first_option, option_length);
209
210 return 0;
211 }
212