xref: /netbsd-src/sys/kern/subr_tftproot.c (revision 56a34939419542e88b386b2229be7565f4f45461)
1 /*	$NetBSD: subr_tftproot.c,v 1.5 2008/04/24 11:38:36 ad Exp $ */
2 
3 /*-
4  * Copyright (c) 2007 Emmanuel Dreyfus, all rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Emmanuel Dreyfus
17  * 4. The name of the author may not be used to endorse or promote
18  *    products derived from this software without specific prior written
19  *    permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS''
22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
23  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Download the root RAMdisk through TFTP at root mount time
36  */
37 
38 #include "opt_tftproot.h"
39 #include "opt_md.h"
40 
41 #include <sys/cdefs.h>
42 __KERNEL_RCSID(0, "$NetBSD: subr_tftproot.c,v 1.5 2008/04/24 11:38:36 ad Exp $");
43 
44 #include <sys/param.h>
45 #include <sys/types.h>
46 #include <sys/mount.h>
47 #include <sys/lwp.h>
48 #include <sys/kmem.h>
49 #include <sys/mbuf.h>
50 #include <sys/timevar.h>
51 #include <sys/socketvar.h>
52 
53 #include <net/if.h>
54 
55 #include <dev/md.h>
56 
57 #include <netinet/in.h>
58 
59 #include <nfs/rpcv2.h>
60 
61 #include <nfs/nfsproto.h>
62 #include <nfs/nfs.h>
63 #include <nfs/nfsmount.h>
64 #include <nfs/nfsdiskless.h>
65 #include <nfs/nfs_var.h>
66 
67 extern void       mdattach(int);
68 
69 /*
70  * Copied from <lib/libsa/tftp.h>
71  */
72 
73 #define SEGSIZE         512             /* data segment size */
74 
75 /*
76  * Packet types.
77  */
78 #define RRQ     01                      /* read request */
79 #define WRQ     02                      /* write request */
80 #define DATA    03                      /* data packet */
81 #define ACK     04                      /* acknowledgement */
82 #define ERROR   05                      /* error code */
83 
84 struct  tftphdr {
85         short   th_opcode;              /* packet type */
86         union {
87                 unsigned short tu_block; /* block # */
88                 short   tu_code;        /* error code */
89                 char    tu_stuff[1];    /* request packet stuff */
90         } th_u;
91         char    th_data[1];             /* data or error string */
92 } __packed;
93 
94 #define th_block        th_u.tu_block
95 #define th_code         th_u.tu_code
96 #define th_stuff        th_u.tu_stuff
97 #define th_msg          th_data
98 
99 #define IPPORT_TFTP 69
100 
101 #ifdef TFTPROOT_DEBUG
102 #define DPRINTF(x) printf x
103 #else
104 #define DPRINTF(x)
105 #endif
106 
107 struct tftproot_handle {
108 	struct nfs_diskless *trh_nd;
109 	void *trh_base;
110 	size_t trh_len;
111 	unsigned short trh_block;
112 	int trh_flags;
113 };
114 
115 #define TRH_FINISHED	1
116 
117 int tftproot_dhcpboot(struct device *);
118 
119 static int tftproot_getfile(struct tftproot_handle *, struct lwp *);
120 static int tftproot_recv __P((struct mbuf*, void*));
121 
122 int
123 tftproot_dhcpboot(bootdv)
124 	struct device *bootdv;
125 {
126 	struct nfs_diskless *nd = NULL;
127 	struct ifnet *ifp = NULL;
128 	struct lwp *l;
129 	struct tftproot_handle trh;
130 	struct device *dv;
131 	int error = -1;
132 
133 	if (rootspec != NULL) {
134 		IFNET_FOREACH(ifp)
135 			if (strcmp(rootspec, ifp->if_xname) == 0)
136 				break;
137 	} else if ((bootdv != NULL && device_class(bootdv) == DV_IFNET)) {
138 		IFNET_FOREACH(ifp)
139 			if (strcmp(device_xname(bootdv), ifp->if_xname) == 0)
140 				break;
141 	}
142 
143 	if (ifp == NULL) {
144 		DPRINTF(("%s():%d ifp is NULL\n", __func__, __LINE__));
145 		goto out;
146 	}
147 
148 	dv = device_find_by_xname(ifp->if_xname);
149 
150 	if ((dv == NULL) || (device_class(dv) != DV_IFNET)) {
151 		DPRINTF(("%s():%d cannot find device for interface %s\n",
152 		    __func__, __LINE__, ifp->if_xname));
153 		goto out;
154 	}
155 
156 	root_device = dv;
157 
158 	l = curlwp; /* XXX */
159 
160 	nd = kmem_zalloc(sizeof(*nd), KM_SLEEP);
161 	nd->nd_ifp = ifp;
162 	nd->nd_nomount = 1;
163 
164 	if ((error = nfs_boot_init(nd, l)) != 0) {
165 		DPRINTF(("%s():%d nfs_boot_init returned %d\n",
166 		    __func__, __LINE__, error));
167 		goto out;
168 	}
169 
170 	/*
171 	 * Strip leading "tftp:"
172 	 */
173 #define PREFIX "tftp:"
174 	if (strstr(nd->nd_bootfile, PREFIX) == nd->nd_bootfile)
175 		(void)memmove(nd->nd_bootfile,
176 			      nd->nd_bootfile + (sizeof(PREFIX) - 1),
177 			      sizeof(nd->nd_bootfile) - sizeof(PREFIX));
178 #undef PREFIX
179 
180 	printf("tftproot: bootfile=%s\n", nd->nd_bootfile);
181 
182 	bzero(&trh, sizeof(trh));
183 	trh.trh_nd = nd;
184 	trh.trh_block = 1;
185 
186 	if ((error = tftproot_getfile(&trh, l)) != 0) {
187 		DPRINTF(("%s():%d tftproot_getfile returned %d\n",
188 		    __func__, __LINE__, error));
189 		goto out;
190 	}
191 
192 	error = 0;
193 
194 out:
195 	if (nd)
196 		kmem_free(nd, sizeof(*nd));
197 
198 	return error;
199 }
200 
201 static int
202 tftproot_getfile(trh, l)
203 	struct tftproot_handle *trh;
204 	struct lwp *l;
205 {
206 	struct socket *so = NULL;
207 	struct mbuf *m_serv = NULL;
208 	struct mbuf *m_outbuf = NULL;
209 	struct sockaddr_in *sin;
210 	struct tftphdr *tftp;
211 	size_t packetlen, namelen;
212 	int error = -1;
213 	const char octetstr[] = "octet";
214 	size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data);
215 	char *cp;
216 	/* struct device *dv; */
217 
218 	if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, l, NULL)) != 0) {
219 		DPRINTF(("%s():%d socreate returned %d\n",
220 		    __func__, __LINE__, error));
221 		goto out;
222 	}
223 
224 	/*
225 	 * Set timeout
226 	 */
227 	if ((error = nfs_boot_setrecvtimo(so))) {
228 		DPRINTF(("%s():%d SO_RCVTIMEO failed %d\n",
229 		    __func__, __LINE__, error));
230 		goto out;
231 	}
232 
233 	/*
234 	 * Set server address and port
235 	 */
236 	m_serv = m_get(M_WAIT, MT_SONAME);
237 	m_serv->m_len = sizeof(*sin);
238 	sin = mtod(m_serv, struct sockaddr_in *);
239 	memcpy(sin, &trh->trh_nd->nd_root.ndm_saddr, sizeof(*sin));
240 	sin->sin_port = htons(IPPORT_TFTP);
241 
242 	/*
243 	 * Set send buffer, prepare the TFTP packet
244 	 */
245 	namelen = strlen(trh->trh_nd->nd_bootfile) + 1;
246 	packetlen = sizeof(tftp->th_opcode) + namelen + sizeof(octetstr);
247 	if (packetlen > MSIZE) {
248 		DPRINTF(("%s():%d boot filename too long (%ld bytes)\n",
249 		    __func__, __LINE__, (long)namelen));
250 		goto out;
251 	}
252 
253 	m_outbuf = m_gethdr(M_WAIT, MT_DATA);
254 	m_clget(m_outbuf, M_WAIT);
255 	m_outbuf->m_len = packetlen;
256 	m_outbuf->m_pkthdr.len = packetlen;
257 	m_outbuf->m_pkthdr.rcvif = NULL;
258 
259 	tftp = mtod(m_outbuf, struct tftphdr *);
260 	memset(tftp, 0, packetlen);
261 
262 	tftp->th_opcode = htons((short)RRQ);
263 	cp = tftp->th_stuff;
264 	(void)strncpy(cp,  trh->trh_nd->nd_bootfile, namelen);
265 	cp += namelen;
266 	(void)strncpy(cp, octetstr, sizeof(octetstr));
267 
268 	/*
269 	 * Perform the file transfer
270 	 */
271 	sin = (struct sockaddr_in *)&trh->trh_nd->nd_root.ndm_saddr;
272 	printf("tftproot: download %s:%s ",
273 	    inet_ntoa(sin->sin_addr), trh->trh_nd->nd_bootfile);
274 
275 	do {
276 		/*
277 		 * Show progress for every 200 blocks (100kB)
278 		 */
279 #ifndef TFTPROOT_PROGRESS
280 #define TFTPROOT_PROGRESS 200
281 #endif
282 		if ((trh->trh_block % TFTPROOT_PROGRESS) == 0)
283 			twiddle();
284 
285 		/*
286 		 * Send the packet and receive the answer.
287 		 * We get the sender address here, which should be
288 		 * the same server with a different port
289 		 */
290 		if ((error = nfs_boot_sendrecv(so, m_serv, NULL, m_outbuf,
291 		    tftproot_recv, NULL, &m_serv, trh, l)) != 0) {
292 			DPRINTF(("%s():%d sendrecv failed %d\n",
293 			    __func__, __LINE__, error));
294 			goto out;
295 		}
296 
297 		/*
298 		 * Accomodate the packet length for acks.
299 		 * This is really needed only on first pass
300 		 */
301 		m_outbuf->m_len = hdrlen;
302 		m_outbuf->m_pkthdr.len = hdrlen;
303 		tftp->th_opcode = htons((short)ACK);
304 		tftp->th_block = htons(trh->trh_block);
305 
306 
307 		/*
308 		 * Check for termination
309 		 */
310 		if (trh->trh_flags & TRH_FINISHED)
311 			break;
312 
313 		trh->trh_block++;
314 	} while (1/* CONSTCOND */);
315 
316 	printf("\n");
317 
318 	/*
319 	 * Ack the last block. so_send frees m_outbuf, therefore
320 	 * we do not want to free it ourselves.
321 	 * Ignore errors, as we already have the whole file.
322 	 */
323 	if ((error = (*so->so_send)(so, m_serv, NULL,
324 	    m_outbuf, NULL, 0, l)) != 0)
325 		DPRINTF(("%s():%d tftproot: sosend returned %d\n",
326 		    __func__, __LINE__, error));
327 	else
328 		m_outbuf = NULL;
329 
330 	/*
331 	 * And use it as the root ramdisk.
332 	 */
333 	DPRINTF(("%s():%d RAMdisk loaded: %ld@%p\n",
334 	    __func__, __LINE__, trh->trh_len, trh->trh_base));
335 	md_root_setconf(trh->trh_base, trh->trh_len);
336 	mdattach(0);
337 
338 	error = 0;
339 out:
340 	if (m_serv)
341 		m_freem(m_serv);
342 
343 	if (m_outbuf)
344 		m_freem(m_outbuf);
345 
346 	if (so)
347 		soclose(so);
348 
349 	return error;
350 }
351 
352 static int
353 tftproot_recv(m, ctx)
354 	struct mbuf *m;
355 	void *ctx;
356 {
357 	struct tftproot_handle *trh = ctx;
358 	struct tftphdr *tftp;
359 	size_t newlen;
360 	size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data);
361 
362 	/*
363 	 * Check for short packet
364 	 */
365 	if (m->m_pkthdr.len < hdrlen) {
366 		DPRINTF(("%s():%d short reply (%d bytes)\n",
367 		    __func__, __LINE__, m->m_pkthdr.len));
368 		return -1;
369 	}
370 
371 	/*
372 	 * Check for packet too large for being a TFTP packet
373 	 */
374 	if (m->m_pkthdr.len > hdrlen + SEGSIZE) {
375 		DPRINTF(("%s():%d packet too big (%d bytes)\n",
376 		    __func__, __LINE__, m->m_pkthdr.len));
377 		return -1;
378 	}
379 
380 
381 	/*
382 	 * Examine the TFTP header
383 	 */
384 	if (m->m_len > sizeof(*tftp)) {
385 		if ((m = m_pullup(m, sizeof(*tftp))) == NULL) {
386 			DPRINTF(("%s():%d m_pullup failed\n",
387 			    __func__, __LINE__));
388 			return -1;
389 		}
390 	}
391 	tftp = mtod(m, struct tftphdr *);
392 
393 	/*
394 	 * We handle data or error
395 	 */
396 	switch(ntohs(tftp->th_opcode)) {
397 	case DATA:
398 		break;
399 
400 	case ERROR: {
401 		char errbuf[SEGSIZE + 1];
402 		int i;
403 
404 		for (i = 0; i < SEGSIZE; i++) {
405 			if ((tftp->th_data[i] < ' ') ||
406 			    (tftp->th_data[i] > '~')) {
407 				errbuf[i] = '\0';
408 				break;
409 			}
410 			errbuf[i] = tftp->th_data[i];
411 		}
412 		errbuf[SEGSIZE] = '\0';
413 
414 		printf("tftproot: TFTP server returned error %d, %s\n",
415 		    ntohs(tftp->th_code), errbuf);
416 
417 		return -1;
418 		break;
419 	}
420 
421 	default:
422 		DPRINTF(("%s():%d unexpected tftp reply opcode %d\n",
423 		    __func__, __LINE__, ntohs(tftp->th_opcode)));
424 		return -1;
425 		break;
426 	}
427 
428 	/*
429 	 * Check for last packet, which does not fill the whole space
430 	 */
431 	if (m->m_pkthdr.len < hdrlen + SEGSIZE) {
432 		DPRINTF(("%s():%d last chunk (%d bytes)\n",
433 		    __func__, __LINE__, m->m_pkthdr.len));
434 		trh->trh_flags |= TRH_FINISHED;
435 	}
436 
437 
438 	if (ntohs(tftp->th_block) != trh->trh_block) {
439 		DPRINTF(("%s():%d expected block %d, got block %d\n",
440 		    __func__, __LINE__, trh->trh_block, ntohs(tftp->th_block)));
441 		return -1;
442 	}
443 
444 	/*
445 	 * Grow the receiving buffer to accomodate new data
446 	 */
447 	newlen = trh->trh_len + (m->m_pkthdr.len - hdrlen);
448 	if ((trh->trh_base = realloc(trh->trh_base,
449 	    newlen, M_TEMP, M_WAITOK)) == NULL) {
450 		DPRINTF(("%s():%d failed to realloc %ld bytes\n",
451 		    __func__, __LINE__, (long)newlen));
452 		return -1;
453 	}
454 
455 	/*
456 	 * Copy the data
457 	 */
458 	m_copydata(m, hdrlen, m->m_pkthdr.len - hdrlen,
459 		   (char *)trh->trh_base + trh->trh_len);
460 	trh->trh_len = newlen;
461 
462 	return 0;
463 }
464 
465