2 * QEMU BOOTP/DHCP server
4 * Copyright (c) 2004 Fabrice Bellard
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
26 /* XXX: only DHCP is supported */
32 #define LEASE_TIME (24 * 3600)
39 BOOTPClient bootp_clients
[NB_ADDR
];
41 static const uint8_t rfc1533_cookie
[] = { RFC1533_COOKIE
};
44 #define dprintf(fmt, args...) \
45 if (slirp_debug & DBG_CALL) { fprintf(dfd, fmt, ## args); fflush(dfd); }
47 #define dprintf(fmt, args...)
50 static BOOTPClient
*get_new_addr(struct in_addr
*paddr
)
55 for(i
= 0; i
< NB_ADDR
; i
++) {
56 if (!bootp_clients
[i
].allocated
)
61 bc
= &bootp_clients
[i
];
63 paddr
->s_addr
= htonl(ntohl(special_addr
.s_addr
) | (i
+ START_ADDR
));
67 static BOOTPClient
*find_addr(struct in_addr
*paddr
, const uint8_t *macaddr
)
72 for(i
= 0; i
< NB_ADDR
; i
++) {
73 if (!memcmp(macaddr
, bootp_clients
[i
].macaddr
, 6))
78 bc
= &bootp_clients
[i
];
80 paddr
->s_addr
= htonl(ntohl(special_addr
.s_addr
) | (i
+ START_ADDR
));
84 static void dhcp_decode(const uint8_t *buf
, int size
,
87 const uint8_t *p
, *p_end
;
96 if (memcmp(p
, rfc1533_cookie
, 4) != 0)
101 if (tag
== RFC1533_PAD
) {
103 } else if (tag
== RFC1533_END
) {
110 dprintf("dhcp: tag=0x%02x len=%d\n", tag
, len
);
113 case RFC2132_MSG_TYPE
:
125 static void bootp_reply(struct bootp_t
*bp
)
130 struct sockaddr_in saddr
, daddr
;
131 struct in_addr dns_addr
;
132 int dhcp_msg_type
, val
;
135 /* extract exact DHCP msg type */
136 dhcp_decode(bp
->bp_vend
, DHCP_OPT_LEN
, &dhcp_msg_type
);
137 dprintf("bootp packet op=%d msgtype=%d\n", bp
->bp_op
, dhcp_msg_type
);
139 if (dhcp_msg_type
== 0)
140 dhcp_msg_type
= DHCPREQUEST
; /* Force reply for old BOOTP clients */
142 if (dhcp_msg_type
!= DHCPDISCOVER
&&
143 dhcp_msg_type
!= DHCPREQUEST
)
145 /* XXX: this is a hack to get the client mac address */
146 memcpy(client_ethaddr
, bp
->bp_hwaddr
, 6);
148 if ((m
= m_get()) == NULL
)
150 m
->m_data
+= if_maxlinkhdr
;
151 rbp
= (struct bootp_t
*)m
->m_data
;
152 m
->m_data
+= sizeof(struct udpiphdr
);
153 memset(rbp
, 0, sizeof(struct bootp_t
));
155 if (dhcp_msg_type
== DHCPDISCOVER
) {
157 bc
= get_new_addr(&daddr
.sin_addr
);
159 dprintf("no address left\n");
162 memcpy(bc
->macaddr
, client_ethaddr
, 6);
164 bc
= find_addr(&daddr
.sin_addr
, bp
->bp_hwaddr
);
166 /* if never assigned, behaves as if it was already
167 assigned (windows fix because it remembers its address) */
171 dprintf("offered addr=%08x\n", ntohl(daddr
.sin_addr
.s_addr
));
173 saddr
.sin_addr
.s_addr
= htonl(ntohl(special_addr
.s_addr
) | CTL_ALIAS
);
174 saddr
.sin_port
= htons(BOOTP_SERVER
);
176 daddr
.sin_port
= htons(BOOTP_CLIENT
);
178 rbp
->bp_op
= BOOTP_REPLY
;
179 rbp
->bp_xid
= bp
->bp_xid
;
182 memcpy(rbp
->bp_hwaddr
, bp
->bp_hwaddr
, 6);
184 rbp
->bp_yiaddr
= daddr
.sin_addr
; /* Client IP address */
185 rbp
->bp_siaddr
= saddr
.sin_addr
; /* Server IP address */
188 memcpy(q
, rfc1533_cookie
, 4);
191 if (dhcp_msg_type
== DHCPDISCOVER
) {
192 *q
++ = RFC2132_MSG_TYPE
;
195 } else if (dhcp_msg_type
== DHCPREQUEST
) {
196 *q
++ = RFC2132_MSG_TYPE
;
201 if (dhcp_msg_type
== DHCPDISCOVER
||
202 dhcp_msg_type
== DHCPREQUEST
) {
203 *q
++ = RFC2132_SRV_ID
;
205 memcpy(q
, &saddr
.sin_addr
, 4);
208 *q
++ = RFC1533_NETMASK
;
215 *q
++ = RFC1533_GATEWAY
;
217 memcpy(q
, &saddr
.sin_addr
, 4);
222 dns_addr
.s_addr
= htonl(ntohl(special_addr
.s_addr
) | CTL_DNS
);
223 memcpy(q
, &dns_addr
, 4);
226 *q
++ = RFC2132_LEASE_TIME
;
228 val
= htonl(LEASE_TIME
);
234 m
->m_len
= sizeof(struct bootp_t
) -
235 sizeof(struct ip
) - sizeof(struct udphdr
);
236 udp_output2(NULL
, m
, &saddr
, &daddr
, IPTOS_LOWDELAY
);
239 void bootp_input(struct mbuf
*m
)
241 struct bootp_t
*bp
= (struct bootp_t
*)m
->m_data
;
243 if (bp
->bp_op
== BOOTP_REQUEST
) {