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 static BOOTPClient bootp_clients
[NB_ADDR
];
41 const char *bootp_filename
;
43 static const uint8_t rfc1533_cookie
[] = { RFC1533_COOKIE
};
46 #define dprintf(fmt, ...) \
47 if (slirp_debug & DBG_CALL) { fprintf(dfd, fmt, ## __VA_ARGS__); fflush(dfd); }
49 #define dprintf(fmt, ...)
52 static BOOTPClient
*get_new_addr(struct in_addr
*paddr
)
57 for(i
= 0; i
< NB_ADDR
; i
++) {
58 if (!bootp_clients
[i
].allocated
)
63 bc
= &bootp_clients
[i
];
65 paddr
->s_addr
= htonl(ntohl(special_addr
.s_addr
) | (i
+ START_ADDR
));
69 static BOOTPClient
*request_addr(const struct in_addr
*paddr
,
70 const uint8_t *macaddr
)
72 uint32_t req_addr
= ntohl(paddr
->s_addr
);
73 uint32_t spec_addr
= ntohl(special_addr
.s_addr
);
76 if (req_addr
>= (spec_addr
| START_ADDR
) &&
77 req_addr
< (spec_addr
| (NB_ADDR
+ START_ADDR
))) {
78 bc
= &bootp_clients
[(req_addr
& 0xff) - START_ADDR
];
79 if (!bc
->allocated
|| !memcmp(macaddr
, bc
->macaddr
, 6)) {
87 static BOOTPClient
*find_addr(struct in_addr
*paddr
, const uint8_t *macaddr
)
92 for(i
= 0; i
< NB_ADDR
; i
++) {
93 if (!memcmp(macaddr
, bootp_clients
[i
].macaddr
, 6))
98 bc
= &bootp_clients
[i
];
100 paddr
->s_addr
= htonl(ntohl(special_addr
.s_addr
) | (i
+ START_ADDR
));
104 static void dhcp_decode(const struct bootp_t
*bp
, int *pmsg_type
,
105 const struct in_addr
**preq_addr
)
107 const uint8_t *p
, *p_end
;
114 p_end
= p
+ DHCP_OPT_LEN
;
115 if (memcmp(p
, rfc1533_cookie
, 4) != 0)
120 if (tag
== RFC1533_PAD
) {
122 } else if (tag
== RFC1533_END
) {
129 dprintf("dhcp: tag=%d len=%d\n", tag
, len
);
132 case RFC2132_MSG_TYPE
:
136 case RFC2132_REQ_ADDR
:
138 *preq_addr
= (struct in_addr
*)p
;
146 if (*pmsg_type
== DHCPREQUEST
&& !*preq_addr
&& bp
->bp_ciaddr
.s_addr
) {
147 *preq_addr
= &bp
->bp_ciaddr
;
151 static void bootp_reply(const struct bootp_t
*bp
)
153 BOOTPClient
*bc
= NULL
;
156 struct sockaddr_in saddr
, daddr
;
157 struct in_addr dns_addr
;
158 const struct in_addr
*preq_addr
;
159 int dhcp_msg_type
, val
;
162 /* extract exact DHCP msg type */
163 dhcp_decode(bp
, &dhcp_msg_type
, &preq_addr
);
164 dprintf("bootp packet op=%d msgtype=%d", bp
->bp_op
, dhcp_msg_type
);
166 dprintf(" req_addr=%08x\n", ntohl(preq_addr
->s_addr
));
170 if (dhcp_msg_type
== 0)
171 dhcp_msg_type
= DHCPREQUEST
; /* Force reply for old BOOTP clients */
173 if (dhcp_msg_type
!= DHCPDISCOVER
&&
174 dhcp_msg_type
!= DHCPREQUEST
)
176 /* XXX: this is a hack to get the client mac address */
177 memcpy(client_ethaddr
, bp
->bp_hwaddr
, 6);
179 if ((m
= m_get()) == NULL
)
181 m
->m_data
+= IF_MAXLINKHDR
;
182 rbp
= (struct bootp_t
*)m
->m_data
;
183 m
->m_data
+= sizeof(struct udpiphdr
);
184 memset(rbp
, 0, sizeof(struct bootp_t
));
186 if (dhcp_msg_type
== DHCPDISCOVER
) {
188 bc
= request_addr(preq_addr
, client_ethaddr
);
190 daddr
.sin_addr
= *preq_addr
;
195 bc
= get_new_addr(&daddr
.sin_addr
);
197 dprintf("no address left\n");
201 memcpy(bc
->macaddr
, client_ethaddr
, 6);
202 } else if (preq_addr
) {
203 bc
= request_addr(preq_addr
, client_ethaddr
);
205 daddr
.sin_addr
= *preq_addr
;
206 memcpy(bc
->macaddr
, client_ethaddr
, 6);
208 daddr
.sin_addr
.s_addr
= 0;
211 bc
= find_addr(&daddr
.sin_addr
, bp
->bp_hwaddr
);
213 /* if never assigned, behaves as if it was already
214 assigned (windows fix because it remembers its address) */
219 saddr
.sin_addr
.s_addr
= htonl(ntohl(special_addr
.s_addr
) | CTL_ALIAS
);
220 saddr
.sin_port
= htons(BOOTP_SERVER
);
222 daddr
.sin_port
= htons(BOOTP_CLIENT
);
224 rbp
->bp_op
= BOOTP_REPLY
;
225 rbp
->bp_xid
= bp
->bp_xid
;
228 memcpy(rbp
->bp_hwaddr
, bp
->bp_hwaddr
, 6);
230 rbp
->bp_yiaddr
= daddr
.sin_addr
; /* Client IP address */
231 rbp
->bp_siaddr
= saddr
.sin_addr
; /* Server IP address */
234 memcpy(q
, rfc1533_cookie
, 4);
238 dprintf("%s addr=%08x\n",
239 (dhcp_msg_type
== DHCPDISCOVER
) ? "offered" : "ack'ed",
240 ntohl(daddr
.sin_addr
.s_addr
));
242 if (dhcp_msg_type
== DHCPDISCOVER
) {
243 *q
++ = RFC2132_MSG_TYPE
;
246 } else /* DHCPREQUEST */ {
247 *q
++ = RFC2132_MSG_TYPE
;
253 snprintf((char *)rbp
->bp_file
, sizeof(rbp
->bp_file
), "%s",
256 *q
++ = RFC2132_SRV_ID
;
258 memcpy(q
, &saddr
.sin_addr
, 4);
261 *q
++ = RFC1533_NETMASK
;
268 if (!slirp_restrict
) {
269 *q
++ = RFC1533_GATEWAY
;
271 memcpy(q
, &saddr
.sin_addr
, 4);
276 dns_addr
.s_addr
= htonl(ntohl(special_addr
.s_addr
) | CTL_DNS
);
277 memcpy(q
, &dns_addr
, 4);
281 *q
++ = RFC2132_LEASE_TIME
;
283 val
= htonl(LEASE_TIME
);
287 if (*slirp_hostname
) {
288 val
= strlen(slirp_hostname
);
289 *q
++ = RFC1533_HOSTNAME
;
291 memcpy(q
, slirp_hostname
, val
);
295 static const char nak_msg
[] = "requested address not available";
297 dprintf("nak'ed addr=%08x\n", ntohl(preq_addr
->s_addr
));
299 *q
++ = RFC2132_MSG_TYPE
;
303 *q
++ = RFC2132_MESSAGE
;
304 *q
++ = sizeof(nak_msg
) - 1;
305 memcpy(q
, nak_msg
, sizeof(nak_msg
) - 1);
306 q
+= sizeof(nak_msg
) - 1;
310 daddr
.sin_addr
.s_addr
= 0xffffffffu
;
312 m
->m_len
= sizeof(struct bootp_t
) -
313 sizeof(struct ip
) - sizeof(struct udphdr
);
314 udp_output2(NULL
, m
, &saddr
, &daddr
, IPTOS_LOWDELAY
);
317 void bootp_input(struct mbuf
*m
)
319 struct bootp_t
*bp
= mtod(m
, struct bootp_t
*);
321 if (bp
->bp_op
== BOOTP_REQUEST
) {