xref: /netbsd-src/sys/kern/subr_tftproot.c (revision b5677b36047b601b9addaaa494a58ceae82c2a6c)
1 /*	$NetBSD: subr_tftproot.c,v 1.8 2009/03/18 16:00:21 cegger 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 1.8 2009/03/18 16:00:21 cegger 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(struct mbuf*, void*);
121 
122 int
123 tftproot_dhcpboot(struct device *bootdv)
124 {
125 	struct nfs_diskless *nd = NULL;
126 	struct ifnet *ifp = NULL;
127 	struct lwp *l;
128 	struct tftproot_handle trh;
129 	struct device *dv;
130 	int error = -1;
131 
132 	if (rootspec != NULL) {
133 		IFNET_FOREACH(ifp)
134 			if (strcmp(rootspec, ifp->if_xname) == 0)
135 				break;
136 	} else if ((bootdv != NULL && device_class(bootdv) == DV_IFNET)) {
137 		IFNET_FOREACH(ifp)
138 			if (strcmp(device_xname(bootdv), ifp->if_xname) == 0)
139 				break;
140 	}
141 
142 	if (ifp == NULL) {
143 		DPRINTF(("%s():%d ifp is NULL\n", __func__, __LINE__));
144 		goto out;
145 	}
146 
147 	dv = device_find_by_xname(ifp->if_xname);
148 
149 	if ((dv == NULL) || (device_class(dv) != DV_IFNET)) {
150 		DPRINTF(("%s():%d cannot find device for interface %s\n",
151 		    __func__, __LINE__, ifp->if_xname));
152 		goto out;
153 	}
154 
155 	root_device = dv;
156 
157 	l = curlwp; /* XXX */
158 
159 	nd = kmem_zalloc(sizeof(*nd), KM_SLEEP);
160 	nd->nd_ifp = ifp;
161 	nd->nd_nomount = 1;
162 
163 	if ((error = nfs_boot_init(nd, l)) != 0) {
164 		DPRINTF(("%s():%d nfs_boot_init returned %d\n",
165 		    __func__, __LINE__, error));
166 		goto out;
167 	}
168 
169 	/*
170 	 * Strip leading "tftp:"
171 	 */
172 #define PREFIX "tftp:"
173 	if (strstr(nd->nd_bootfile, PREFIX) == nd->nd_bootfile)
174 		(void)memmove(nd->nd_bootfile,
175 			      nd->nd_bootfile + (sizeof(PREFIX) - 1),
176 			      sizeof(nd->nd_bootfile) - sizeof(PREFIX));
177 #undef PREFIX
178 
179 	printf("tftproot: bootfile=%s\n", nd->nd_bootfile);
180 
181 	memset(&trh, 0, sizeof(trh));
182 	trh.trh_nd = nd;
183 	trh.trh_block = 1;
184 
185 	if ((error = tftproot_getfile(&trh, l)) != 0) {
186 		DPRINTF(("%s():%d tftproot_getfile returned %d\n",
187 		    __func__, __LINE__, error));
188 		goto out;
189 	}
190 
191 	error = 0;
192 
193 out:
194 	if (nd)
195 		kmem_free(nd, sizeof(*nd));
196 
197 	return error;
198 }
199 
200 static int
201 tftproot_getfile(struct tftproot_handle *trh, struct lwp *l)
202 {
203 	struct socket *so = NULL;
204 	struct mbuf *m_serv = NULL;
205 	struct mbuf *m_outbuf = NULL;
206 	struct sockaddr_in *sin;
207 	struct tftphdr *tftp;
208 	size_t packetlen, namelen;
209 	int error = -1;
210 	const char octetstr[] = "octet";
211 	size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data);
212 	char *cp;
213 	/* struct device *dv; */
214 
215 	if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, l, NULL)) != 0) {
216 		DPRINTF(("%s():%d socreate returned %d\n",
217 		    __func__, __LINE__, error));
218 		goto out;
219 	}
220 
221 	/*
222 	 * Set timeout
223 	 */
224 	if ((error = nfs_boot_setrecvtimo(so))) {
225 		DPRINTF(("%s():%d SO_RCVTIMEO failed %d\n",
226 		    __func__, __LINE__, error));
227 		goto out;
228 	}
229 
230 	/*
231 	 * Set server address and port
232 	 */
233 	m_serv = m_get(M_WAIT, MT_SONAME);
234 	m_serv->m_len = sizeof(*sin);
235 	sin = mtod(m_serv, struct sockaddr_in *);
236 	memcpy(sin, &trh->trh_nd->nd_root.ndm_saddr, sizeof(*sin));
237 	sin->sin_port = htons(IPPORT_TFTP);
238 
239 	/*
240 	 * Set send buffer, prepare the TFTP packet
241 	 */
242 	namelen = strlen(trh->trh_nd->nd_bootfile) + 1;
243 	packetlen = sizeof(tftp->th_opcode) + namelen + sizeof(octetstr);
244 	if (packetlen > MSIZE) {
245 		DPRINTF(("%s():%d boot filename too long (%ld bytes)\n",
246 		    __func__, __LINE__, (long)namelen));
247 		goto out;
248 	}
249 
250 	m_outbuf = m_gethdr(M_WAIT, MT_DATA);
251 	m_clget(m_outbuf, M_WAIT);
252 	m_outbuf->m_len = packetlen;
253 	m_outbuf->m_pkthdr.len = packetlen;
254 	m_outbuf->m_pkthdr.rcvif = NULL;
255 
256 	tftp = mtod(m_outbuf, struct tftphdr *);
257 	memset(tftp, 0, packetlen);
258 
259 	tftp->th_opcode = htons((short)RRQ);
260 	cp = tftp->th_stuff;
261 	(void)strncpy(cp,  trh->trh_nd->nd_bootfile, namelen);
262 	cp += namelen;
263 	(void)strncpy(cp, octetstr, sizeof(octetstr));
264 
265 	/*
266 	 * Perform the file transfer
267 	 */
268 	sin = (struct sockaddr_in *)&trh->trh_nd->nd_root.ndm_saddr;
269 	printf("tftproot: download %s:%s ",
270 	    inet_ntoa(sin->sin_addr), trh->trh_nd->nd_bootfile);
271 
272 	do {
273 		/*
274 		 * Show progress for every 200 blocks (100kB)
275 		 */
276 #ifndef TFTPROOT_PROGRESS
277 #define TFTPROOT_PROGRESS 200
278 #endif
279 		if ((trh->trh_block % TFTPROOT_PROGRESS) == 0)
280 			twiddle();
281 
282 		/*
283 		 * Send the packet and receive the answer.
284 		 * We get the sender address here, which should be
285 		 * the same server with a different port
286 		 */
287 		if ((error = nfs_boot_sendrecv(so, m_serv, NULL, m_outbuf,
288 		    tftproot_recv, NULL, &m_serv, trh, l)) != 0) {
289 			DPRINTF(("%s():%d sendrecv failed %d\n",
290 			    __func__, __LINE__, error));
291 			goto out;
292 		}
293 
294 		/*
295 		 * Accomodate the packet length for acks.
296 		 * This is really needed only on first pass
297 		 */
298 		m_outbuf->m_len = hdrlen;
299 		m_outbuf->m_pkthdr.len = hdrlen;
300 		tftp->th_opcode = htons((short)ACK);
301 		tftp->th_block = htons(trh->trh_block);
302 
303 
304 		/*
305 		 * Check for termination
306 		 */
307 		if (trh->trh_flags & TRH_FINISHED)
308 			break;
309 
310 		trh->trh_block++;
311 	} while (1/* CONSTCOND */);
312 
313 	printf("\n");
314 
315 	/*
316 	 * Ack the last block. so_send frees m_outbuf, therefore
317 	 * we do not want to free it ourselves.
318 	 * Ignore errors, as we already have the whole file.
319 	 */
320 	if ((error = (*so->so_send)(so, m_serv, NULL,
321 	    m_outbuf, NULL, 0, l)) != 0)
322 		DPRINTF(("%s():%d tftproot: sosend returned %d\n",
323 		    __func__, __LINE__, error));
324 	else
325 		m_outbuf = NULL;
326 
327 	/*
328 	 * And use it as the root ramdisk.
329 	 */
330 	DPRINTF(("%s():%d RAMdisk loaded: %ld@%p\n",
331 	    __func__, __LINE__, trh->trh_len, trh->trh_base));
332 	md_root_setconf(trh->trh_base, trh->trh_len);
333 	mdattach(0);
334 
335 	error = 0;
336 out:
337 	if (m_serv)
338 		m_freem(m_serv);
339 
340 	if (m_outbuf)
341 		m_freem(m_outbuf);
342 
343 	if (so)
344 		soclose(so);
345 
346 	return error;
347 }
348 
349 static int
350 tftproot_recv(struct mbuf *m, void *ctx)
351 {
352 	struct tftproot_handle *trh = ctx;
353 	struct tftphdr *tftp;
354 	size_t newlen;
355 	size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data);
356 
357 	/*
358 	 * Check for short packet
359 	 */
360 	if (m->m_pkthdr.len < hdrlen) {
361 		DPRINTF(("%s():%d short reply (%d bytes)\n",
362 		    __func__, __LINE__, m->m_pkthdr.len));
363 		return -1;
364 	}
365 
366 	/*
367 	 * Check for packet too large for being a TFTP packet
368 	 */
369 	if (m->m_pkthdr.len > hdrlen + SEGSIZE) {
370 		DPRINTF(("%s():%d packet too big (%d bytes)\n",
371 		    __func__, __LINE__, m->m_pkthdr.len));
372 		return -1;
373 	}
374 
375 
376 	/*
377 	 * Examine the TFTP header
378 	 */
379 	if (m->m_len > sizeof(*tftp)) {
380 		if ((m = m_pullup(m, sizeof(*tftp))) == NULL) {
381 			DPRINTF(("%s():%d m_pullup failed\n",
382 			    __func__, __LINE__));
383 			return -1;
384 		}
385 	}
386 	tftp = mtod(m, struct tftphdr *);
387 
388 	/*
389 	 * We handle data or error
390 	 */
391 	switch(ntohs(tftp->th_opcode)) {
392 	case DATA:
393 		break;
394 
395 	case ERROR: {
396 		char errbuf[SEGSIZE + 1];
397 		int i;
398 
399 		for (i = 0; i < SEGSIZE; i++) {
400 			if ((tftp->th_data[i] < ' ') ||
401 			    (tftp->th_data[i] > '~')) {
402 				errbuf[i] = '\0';
403 				break;
404 			}
405 			errbuf[i] = tftp->th_data[i];
406 		}
407 		errbuf[SEGSIZE] = '\0';
408 
409 		printf("tftproot: TFTP server returned error %d, %s\n",
410 		    ntohs(tftp->th_code), errbuf);
411 
412 		return -1;
413 		break;
414 	}
415 
416 	default:
417 		DPRINTF(("%s():%d unexpected tftp reply opcode %d\n",
418 		    __func__, __LINE__, ntohs(tftp->th_opcode)));
419 		return -1;
420 		break;
421 	}
422 
423 	/*
424 	 * Check for last packet, which does not fill the whole space
425 	 */
426 	if (m->m_pkthdr.len < hdrlen + SEGSIZE) {
427 		DPRINTF(("%s():%d last chunk (%d bytes)\n",
428 		    __func__, __LINE__, m->m_pkthdr.len));
429 		trh->trh_flags |= TRH_FINISHED;
430 	}
431 
432 
433 	if (ntohs(tftp->th_block) != trh->trh_block) {
434 		DPRINTF(("%s():%d expected block %d, got block %d\n",
435 		    __func__, __LINE__, trh->trh_block, ntohs(tftp->th_block)));
436 		return -1;
437 	}
438 
439 	/*
440 	 * Grow the receiving buffer to accomodate new data
441 	 */
442 	newlen = trh->trh_len + (m->m_pkthdr.len - hdrlen);
443 	if ((trh->trh_base = realloc(trh->trh_base,
444 	    newlen, M_TEMP, M_WAITOK)) == NULL) {
445 		DPRINTF(("%s():%d failed to realloc %ld bytes\n",
446 		    __func__, __LINE__, (long)newlen));
447 		return -1;
448 	}
449 
450 	/*
451 	 * Copy the data
452 	 */
453 	m_copydata(m, hdrlen, m->m_pkthdr.len - hdrlen,
454 		   (char *)trh->trh_base + trh->trh_len);
455 	trh->trh_len = newlen;
456 
457 	return 0;
458 }
459 
460