]>
Commit | Line | Data |
---|---|---|
f0cbd3ec FB |
1 | /* |
2 | * QEMU BOOTP/DHCP server | |
5fafdf24 | 3 | * |
f0cbd3ec | 4 | * Copyright (c) 2004 Fabrice Bellard |
5fafdf24 | 5 | * |
f0cbd3ec FB |
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: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
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 | |
22 | * THE SOFTWARE. | |
23 | */ | |
24 | #include <slirp.h> | |
25 | ||
26 | /* XXX: only DHCP is supported */ | |
27 | ||
28 | #define NB_ADDR 16 | |
29 | ||
f0cbd3ec FB |
30 | #define LEASE_TIME (24 * 3600) |
31 | ||
32 | typedef struct { | |
33 | uint8_t allocated; | |
512176db | 34 | uint8_t macaddr[6]; |
f0cbd3ec FB |
35 | } BOOTPClient; |
36 | ||
7ca699c8 | 37 | static BOOTPClient bootp_clients[NB_ADDR]; |
f0cbd3ec | 38 | |
ad196a9d | 39 | char *bootp_filename; |
47d5d01a | 40 | |
f0cbd3ec FB |
41 | static const uint8_t rfc1533_cookie[] = { RFC1533_COOKIE }; |
42 | ||
43 | #ifdef DEBUG | |
001faf32 | 44 | #define dprintf(fmt, ...) \ |
9f349498 | 45 | do if (slirp_debug & DBG_CALL) { fprintf(dfd, fmt, ## __VA_ARGS__); fflush(dfd); } while (0) |
f0cbd3ec | 46 | #else |
001faf32 | 47 | #define dprintf(fmt, ...) |
f0cbd3ec FB |
48 | #endif |
49 | ||
0928a95f JK |
50 | static BOOTPClient *get_new_addr(struct in_addr *paddr, |
51 | const uint8_t *macaddr) | |
f0cbd3ec FB |
52 | { |
53 | BOOTPClient *bc; | |
54 | int i; | |
55 | ||
56 | for(i = 0; i < NB_ADDR; i++) { | |
0928a95f JK |
57 | bc = &bootp_clients[i]; |
58 | if (!bc->allocated || !memcmp(macaddr, bc->macaddr, 6)) | |
f0cbd3ec FB |
59 | goto found; |
60 | } | |
61 | return NULL; | |
62 | found: | |
63 | bc = &bootp_clients[i]; | |
64 | bc->allocated = 1; | |
a13a4126 | 65 | paddr->s_addr = vdhcp_startaddr.s_addr + htonl(i); |
f0cbd3ec FB |
66 | return bc; |
67 | } | |
68 | ||
b63c7f6b AL |
69 | static BOOTPClient *request_addr(const struct in_addr *paddr, |
70 | const uint8_t *macaddr) | |
71 | { | |
72 | uint32_t req_addr = ntohl(paddr->s_addr); | |
a13a4126 | 73 | uint32_t dhcp_addr = ntohl(vdhcp_startaddr.s_addr); |
b63c7f6b AL |
74 | BOOTPClient *bc; |
75 | ||
a13a4126 JK |
76 | if (req_addr >= dhcp_addr && |
77 | req_addr < (dhcp_addr + NB_ADDR)) { | |
78 | bc = &bootp_clients[req_addr - dhcp_addr]; | |
b63c7f6b AL |
79 | if (!bc->allocated || !memcmp(macaddr, bc->macaddr, 6)) { |
80 | bc->allocated = 1; | |
81 | return bc; | |
82 | } | |
83 | } | |
84 | return NULL; | |
85 | } | |
86 | ||
512176db FB |
87 | static BOOTPClient *find_addr(struct in_addr *paddr, const uint8_t *macaddr) |
88 | { | |
89 | BOOTPClient *bc; | |
90 | int i; | |
91 | ||
92 | for(i = 0; i < NB_ADDR; i++) { | |
93 | if (!memcmp(macaddr, bootp_clients[i].macaddr, 6)) | |
94 | goto found; | |
95 | } | |
96 | return NULL; | |
97 | found: | |
98 | bc = &bootp_clients[i]; | |
99 | bc->allocated = 1; | |
a13a4126 | 100 | paddr->s_addr = vdhcp_startaddr.s_addr + htonl(i); |
512176db FB |
101 | return bc; |
102 | } | |
103 | ||
b63c7f6b AL |
104 | static void dhcp_decode(const struct bootp_t *bp, int *pmsg_type, |
105 | const struct in_addr **preq_addr) | |
f0cbd3ec FB |
106 | { |
107 | const uint8_t *p, *p_end; | |
108 | int len, tag; | |
109 | ||
3b46e624 | 110 | *pmsg_type = 0; |
b63c7f6b | 111 | *preq_addr = NULL; |
f0cbd3ec | 112 | |
b63c7f6b AL |
113 | p = bp->bp_vend; |
114 | p_end = p + DHCP_OPT_LEN; | |
f0cbd3ec FB |
115 | if (memcmp(p, rfc1533_cookie, 4) != 0) |
116 | return; | |
117 | p += 4; | |
118 | while (p < p_end) { | |
119 | tag = p[0]; | |
120 | if (tag == RFC1533_PAD) { | |
5fafdf24 | 121 | p++; |
f0cbd3ec FB |
122 | } else if (tag == RFC1533_END) { |
123 | break; | |
124 | } else { | |
125 | p++; | |
126 | if (p >= p_end) | |
127 | break; | |
128 | len = *p++; | |
b63c7f6b | 129 | dprintf("dhcp: tag=%d len=%d\n", tag, len); |
f0cbd3ec FB |
130 | |
131 | switch(tag) { | |
132 | case RFC2132_MSG_TYPE: | |
133 | if (len >= 1) | |
134 | *pmsg_type = p[0]; | |
135 | break; | |
b63c7f6b AL |
136 | case RFC2132_REQ_ADDR: |
137 | if (len >= 4) | |
138 | *preq_addr = (struct in_addr *)p; | |
139 | break; | |
f0cbd3ec FB |
140 | default: |
141 | break; | |
142 | } | |
143 | p += len; | |
144 | } | |
145 | } | |
b63c7f6b AL |
146 | if (*pmsg_type == DHCPREQUEST && !*preq_addr && bp->bp_ciaddr.s_addr) { |
147 | *preq_addr = &bp->bp_ciaddr; | |
148 | } | |
f0cbd3ec FB |
149 | } |
150 | ||
b63c7f6b | 151 | static void bootp_reply(const struct bootp_t *bp) |
f0cbd3ec | 152 | { |
b63c7f6b | 153 | BOOTPClient *bc = NULL; |
f0cbd3ec FB |
154 | struct mbuf *m; |
155 | struct bootp_t *rbp; | |
156 | struct sockaddr_in saddr, daddr; | |
b63c7f6b | 157 | const struct in_addr *preq_addr; |
f0cbd3ec FB |
158 | int dhcp_msg_type, val; |
159 | uint8_t *q; | |
160 | ||
161 | /* extract exact DHCP msg type */ | |
b63c7f6b AL |
162 | dhcp_decode(bp, &dhcp_msg_type, &preq_addr); |
163 | dprintf("bootp packet op=%d msgtype=%d", bp->bp_op, dhcp_msg_type); | |
164 | if (preq_addr) | |
165 | dprintf(" req_addr=%08x\n", ntohl(preq_addr->s_addr)); | |
166 | else | |
167 | dprintf("\n"); | |
3b46e624 | 168 | |
487be8a1 FB |
169 | if (dhcp_msg_type == 0) |
170 | dhcp_msg_type = DHCPREQUEST; /* Force reply for old BOOTP clients */ | |
3b46e624 | 171 | |
5fafdf24 | 172 | if (dhcp_msg_type != DHCPDISCOVER && |
f0cbd3ec FB |
173 | dhcp_msg_type != DHCPREQUEST) |
174 | return; | |
175 | /* XXX: this is a hack to get the client mac address */ | |
176 | memcpy(client_ethaddr, bp->bp_hwaddr, 6); | |
3b46e624 | 177 | |
f0cbd3ec FB |
178 | if ((m = m_get()) == NULL) |
179 | return; | |
9634d903 | 180 | m->m_data += IF_MAXLINKHDR; |
f0cbd3ec FB |
181 | rbp = (struct bootp_t *)m->m_data; |
182 | m->m_data += sizeof(struct udpiphdr); | |
183 | memset(rbp, 0, sizeof(struct bootp_t)); | |
184 | ||
512176db | 185 | if (dhcp_msg_type == DHCPDISCOVER) { |
b63c7f6b AL |
186 | if (preq_addr) { |
187 | bc = request_addr(preq_addr, client_ethaddr); | |
188 | if (bc) { | |
189 | daddr.sin_addr = *preq_addr; | |
190 | } | |
191 | } | |
512176db | 192 | if (!bc) { |
b63c7f6b | 193 | new_addr: |
0928a95f | 194 | bc = get_new_addr(&daddr.sin_addr, client_ethaddr); |
b63c7f6b AL |
195 | if (!bc) { |
196 | dprintf("no address left\n"); | |
197 | return; | |
198 | } | |
512176db FB |
199 | } |
200 | memcpy(bc->macaddr, client_ethaddr, 6); | |
b63c7f6b AL |
201 | } else if (preq_addr) { |
202 | bc = request_addr(preq_addr, client_ethaddr); | |
203 | if (bc) { | |
204 | daddr.sin_addr = *preq_addr; | |
205 | memcpy(bc->macaddr, client_ethaddr, 6); | |
206 | } else { | |
207 | daddr.sin_addr.s_addr = 0; | |
208 | } | |
512176db FB |
209 | } else { |
210 | bc = find_addr(&daddr.sin_addr, bp->bp_hwaddr); | |
211 | if (!bc) { | |
d981b883 FB |
212 | /* if never assigned, behaves as if it was already |
213 | assigned (windows fix because it remembers its address) */ | |
214 | goto new_addr; | |
512176db | 215 | } |
f0cbd3ec | 216 | } |
47d5d01a | 217 | |
a13a4126 | 218 | saddr.sin_addr = vhost_addr; |
f0cbd3ec FB |
219 | saddr.sin_port = htons(BOOTP_SERVER); |
220 | ||
221 | daddr.sin_port = htons(BOOTP_CLIENT); | |
222 | ||
223 | rbp->bp_op = BOOTP_REPLY; | |
224 | rbp->bp_xid = bp->bp_xid; | |
225 | rbp->bp_htype = 1; | |
226 | rbp->bp_hlen = 6; | |
227 | memcpy(rbp->bp_hwaddr, bp->bp_hwaddr, 6); | |
228 | ||
e95c8d51 FB |
229 | rbp->bp_yiaddr = daddr.sin_addr; /* Client IP address */ |
230 | rbp->bp_siaddr = saddr.sin_addr; /* Server IP address */ | |
f0cbd3ec FB |
231 | |
232 | q = rbp->bp_vend; | |
233 | memcpy(q, rfc1533_cookie, 4); | |
234 | q += 4; | |
235 | ||
b63c7f6b AL |
236 | if (bc) { |
237 | dprintf("%s addr=%08x\n", | |
238 | (dhcp_msg_type == DHCPDISCOVER) ? "offered" : "ack'ed", | |
239 | ntohl(daddr.sin_addr.s_addr)); | |
240 | ||
241 | if (dhcp_msg_type == DHCPDISCOVER) { | |
242 | *q++ = RFC2132_MSG_TYPE; | |
243 | *q++ = 1; | |
244 | *q++ = DHCPOFFER; | |
245 | } else /* DHCPREQUEST */ { | |
246 | *q++ = RFC2132_MSG_TYPE; | |
247 | *q++ = 1; | |
248 | *q++ = DHCPACK; | |
249 | } | |
250 | ||
251 | if (bootp_filename) | |
252 | snprintf((char *)rbp->bp_file, sizeof(rbp->bp_file), "%s", | |
253 | bootp_filename); | |
3b46e624 | 254 | |
f0cbd3ec FB |
255 | *q++ = RFC2132_SRV_ID; |
256 | *q++ = 4; | |
257 | memcpy(q, &saddr.sin_addr, 4); | |
258 | q += 4; | |
259 | ||
260 | *q++ = RFC1533_NETMASK; | |
261 | *q++ = 4; | |
a13a4126 JK |
262 | memcpy(q, &vnetwork_mask, 4); |
263 | q += 4; | |
3b46e624 | 264 | |
a9ba3a85 AL |
265 | if (!slirp_restrict) { |
266 | *q++ = RFC1533_GATEWAY; | |
267 | *q++ = 4; | |
268 | memcpy(q, &saddr.sin_addr, 4); | |
269 | q += 4; | |
270 | ||
271 | *q++ = RFC1533_DNS; | |
272 | *q++ = 4; | |
a13a4126 | 273 | memcpy(q, &vnameserver_addr, 4); |
a9ba3a85 AL |
274 | q += 4; |
275 | } | |
f0cbd3ec FB |
276 | |
277 | *q++ = RFC2132_LEASE_TIME; | |
278 | *q++ = 4; | |
279 | val = htonl(LEASE_TIME); | |
280 | memcpy(q, &val, 4); | |
281 | q += 4; | |
115defd1 PB |
282 | |
283 | if (*slirp_hostname) { | |
284 | val = strlen(slirp_hostname); | |
285 | *q++ = RFC1533_HOSTNAME; | |
286 | *q++ = val; | |
287 | memcpy(q, slirp_hostname, val); | |
288 | q += val; | |
289 | } | |
b63c7f6b AL |
290 | } else { |
291 | static const char nak_msg[] = "requested address not available"; | |
292 | ||
293 | dprintf("nak'ed addr=%08x\n", ntohl(preq_addr->s_addr)); | |
294 | ||
295 | *q++ = RFC2132_MSG_TYPE; | |
296 | *q++ = 1; | |
297 | *q++ = DHCPNAK; | |
298 | ||
299 | *q++ = RFC2132_MESSAGE; | |
300 | *q++ = sizeof(nak_msg) - 1; | |
301 | memcpy(q, nak_msg, sizeof(nak_msg) - 1); | |
302 | q += sizeof(nak_msg) - 1; | |
f0cbd3ec FB |
303 | } |
304 | *q++ = RFC1533_END; | |
3b46e624 | 305 | |
b63c7f6b AL |
306 | daddr.sin_addr.s_addr = 0xffffffffu; |
307 | ||
5fafdf24 | 308 | m->m_len = sizeof(struct bootp_t) - |
44bbf73f | 309 | sizeof(struct ip) - sizeof(struct udphdr); |
f0cbd3ec FB |
310 | udp_output2(NULL, m, &saddr, &daddr, IPTOS_LOWDELAY); |
311 | } | |
312 | ||
313 | void bootp_input(struct mbuf *m) | |
314 | { | |
101c5935 | 315 | struct bootp_t *bp = mtod(m, struct bootp_t *); |
f0cbd3ec FB |
316 | |
317 | if (bp->bp_op == BOOTP_REQUEST) { | |
318 | bootp_reply(bp); | |
319 | } | |
320 | } |