xref: /netbsd-src/sys/kern/subr_tftproot.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: subr_tftproot.c,v 1.1 2007/05/08 06:10:27 manu 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 1.1 2007/05/08 06:10:27 manu 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/malloc.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(bootdv->dv_xname, 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 	for (dv = TAILQ_FIRST(&alldevs); dv != NULL;
149 	     dv = TAILQ_NEXT(dv, dv_list))
150 		if (strcmp(dv->dv_xname, ifp->if_xname) == 0)
151 			break;
152 
153 	if ((dv == NULL) || (device_class(dv) != DV_IFNET)) {
154 		DPRINTF(("%s():%d cannot find device for interface %s\n",
155 		    __func__, __LINE__, ifp->if_xname));
156 		goto out;
157 	}
158 
159 	root_device = dv;
160 
161 	l = curlwp; /* XXX */
162 
163 	nd = malloc(sizeof(*nd), M_NFSMNT, M_WAITOK);
164 	bzero(nd, sizeof(nd));
165 	nd->nd_ifp = ifp;
166 	nd->nd_nomount = 1;
167 
168 	if ((error = nfs_boot_init(nd, l)) != 0) {
169 		DPRINTF(("%s():%d nfs_boot_init returned %d\n",
170 		    __func__, __LINE__, error));
171 		goto out;
172 	}
173 
174 	/*
175 	 * Strip leading "tftp:"
176 	 */
177 #define PREFIX "tftp:"
178 	if (strstr(nd->nd_bootfile, PREFIX) == nd->nd_bootfile)
179 		(void)memmove(nd->nd_bootfile,
180 			      nd->nd_bootfile + (sizeof(PREFIX) - 1),
181 			      sizeof(nd->nd_bootfile) - sizeof(PREFIX));
182 #undef PREFIX
183 
184 	printf("tftproot: bootfile=%s\n", nd->nd_bootfile);
185 
186 	bzero(&trh, sizeof(trh));
187 	trh.trh_nd = nd;
188 	trh.trh_block = 1;
189 
190 	if ((error = tftproot_getfile(&trh, l)) != 0) {
191 		DPRINTF(("%s():%d tftproot_getfile returned %d\n",
192 		    __func__, __LINE__, error));
193 		goto out;
194 	}
195 
196 	error = 0;
197 
198 out:
199 	if (nd)
200 		free(nd, M_NFSMNT);
201 
202 	return error;
203 }
204 
205 static int
206 tftproot_getfile(trh, l)
207 	struct tftproot_handle *trh;
208 	struct lwp *l;
209 {
210 	struct socket *so = NULL;
211 	struct mbuf *m_serv = NULL;
212 	struct mbuf *m_outbuf = NULL;
213 	struct sockaddr_in *sin;
214 	struct tftphdr *tftp;
215 	size_t packetlen, namelen;
216 	int error = -1;
217 	const char octetstr[] = "octet";
218 	size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data);
219 	char *cp;
220 	/* struct device *dv; */
221 
222 	if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, l)) != 0) {
223 		DPRINTF(("%s():%d socreate returned %d\n",
224 		    __func__, __LINE__, error));
225 		goto out;
226 	}
227 
228 	/*
229 	 * Set timeout
230 	 */
231 	if ((error = nfs_boot_setrecvtimo(so))) {
232 		DPRINTF(("%s():%d SO_RCVTIMEO failed %d\n",
233 		    __func__, __LINE__, error));
234 		goto out;
235 	}
236 
237 	/*
238 	 * Set server address and port
239 	 */
240 	m_serv = m_get(M_WAIT, MT_SONAME);
241 	m_serv->m_len = sizeof(*sin);
242 	sin = mtod(m_serv, struct sockaddr_in *);
243 	memcpy(sin, &trh->trh_nd->nd_root.ndm_saddr, sizeof(*sin));
244 	sin->sin_port = htons(IPPORT_TFTP);
245 
246 	/*
247 	 * Set send buffer, prepare the TFTP packet
248 	 */
249 	namelen = strlen(trh->trh_nd->nd_bootfile) + 1;
250 	packetlen = sizeof(tftp->th_opcode) + namelen + sizeof(octetstr);
251 	if (packetlen > MSIZE) {
252 		DPRINTF(("%s():%d boot filename too long (%ld bytes)\n",
253 		    __func__, __LINE__, (long)namelen));
254 		goto out;
255 	}
256 
257 	m_outbuf = m_gethdr(M_WAIT, MT_DATA);
258 	m_clget(m_outbuf, M_WAIT);
259 	m_outbuf->m_len = packetlen;
260 	m_outbuf->m_pkthdr.len = packetlen;
261 	m_outbuf->m_pkthdr.rcvif = NULL;
262 
263 	tftp = mtod(m_outbuf, struct tftphdr *);
264 	memset(tftp, 0, packetlen);
265 
266 	tftp->th_opcode = htons((short)RRQ);
267 	cp = tftp->th_stuff;
268 	(void)strncpy(cp,  trh->trh_nd->nd_bootfile, namelen);
269 	cp += namelen;
270 	(void)strncpy(cp, octetstr, sizeof(octetstr));
271 
272 	/*
273 	 * Perform the file transfer
274 	 */
275 	sin = (struct sockaddr_in *)&trh->trh_nd->nd_root.ndm_saddr;
276 	printf("tftproot: download %s:%s ",
277 	    inet_ntoa(sin->sin_addr), trh->trh_nd->nd_bootfile);
278 
279 	do {
280 		/*
281 		 * Show progress for every 200 blocks (100kB)
282 		 */
283 #ifndef TFTPROOT_PROGRESS
284 #define TFTPROOT_PROGRESS 200
285 #endif
286 		if ((trh->trh_block % TFTPROOT_PROGRESS) == 0)
287 			twiddle();
288 
289 		/*
290 		 * Send the packet and receive the answer.
291 		 * We get the sender address here, which should be
292 		 * the same server with a different port
293 		 */
294 		if ((error = nfs_boot_sendrecv(so, m_serv, NULL, m_outbuf,
295 		    tftproot_recv, NULL, &m_serv, trh, l)) != 0) {
296 			DPRINTF(("%s():%d sendrecv failed %d\n",
297 			    __func__, __LINE__, error));
298 			goto out;
299 		}
300 
301 		/*
302 		 * Accomodate the packet length for acks.
303 		 * This is really needed only on first pass
304 		 */
305 		m_outbuf->m_len = hdrlen;
306 		m_outbuf->m_pkthdr.len = hdrlen;
307 		tftp->th_opcode = htons((short)ACK);
308 		tftp->th_block = htons(trh->trh_block);
309 
310 
311 		/*
312 		 * Check for termination
313 		 */
314 		if (trh->trh_flags & TRH_FINISHED)
315 			break;
316 
317 		trh->trh_block++;
318 	} while (1/* CONSTCOND */);
319 
320 	printf("\n");
321 
322 	/*
323 	 * Ack the last block. so_send frees m_outbuf, therefore
324 	 * we do not want to free it ourselves.
325 	 * Ignore errors, as we already have the whole file.
326 	 */
327 	if ((error = (*so->so_send)(so, m_serv, NULL,
328 	    m_outbuf, NULL, 0, l)) != 0)
329 		DPRINTF(("%s():%d tftproot: sosend returned %d\n",
330 		    __func__, __LINE__, error));
331 	else
332 		m_outbuf = NULL;
333 
334 	/*
335 	 * And use it as the root ramdisk.
336 	 */
337 	DPRINTF(("%s():%d RAMdisk loaded: %ld@%p\n",
338 	    __func__, __LINE__, trh->trh_len, trh->trh_base));
339 	md_root_setconf(trh->trh_base, trh->trh_len);
340 	mdattach(0);
341 
342 	error = 0;
343 out:
344 	if (m_serv)
345 		m_freem(m_serv);
346 
347 	if (m_outbuf)
348 		m_freem(m_outbuf);
349 
350 	if (so)
351 		soclose(so);
352 
353 	return error;
354 }
355 
356 static int
357 tftproot_recv(m, ctx)
358 	struct mbuf *m;
359 	void *ctx;
360 {
361 	struct tftproot_handle *trh = ctx;
362 	struct tftphdr *tftp;
363 	size_t newlen;
364 	size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data);
365 
366 	/*
367 	 * Check for short packet
368 	 */
369 	if (m->m_pkthdr.len < hdrlen) {
370 		DPRINTF(("%s():%d short reply (%d bytes)\n",
371 		    __func__, __LINE__, m->m_pkthdr.len));
372 		return -1;
373 	}
374 
375 	/*
376 	 * Check for packet too large for being a TFTP packet
377 	 */
378 	if (m->m_pkthdr.len > hdrlen + SEGSIZE) {
379 		DPRINTF(("%s():%d packet too big (%d bytes)\n",
380 		    __func__, __LINE__, m->m_pkthdr.len));
381 		return -1;
382 	}
383 
384 
385 	/*
386 	 * Examine the TFTP header
387 	 */
388 	if (m->m_len > sizeof(*tftp)) {
389 		if ((m = m_pullup(m, sizeof(*tftp))) == NULL) {
390 			DPRINTF(("%s():%d m_pullup failed\n",
391 			    __func__, __LINE__));
392 			return -1;
393 		}
394 	}
395 	tftp = mtod(m, struct tftphdr *);
396 
397 	/*
398 	 * We handle data or error
399 	 */
400 	switch(ntohs(tftp->th_opcode)) {
401 	case DATA:
402 		break;
403 
404 	case ERROR: {
405 		char errbuf[SEGSIZE + 1];
406 		int i;
407 
408 		for (i = 0; i < SEGSIZE; i++) {
409 			if ((tftp->th_data[i] < ' ') ||
410 			    (tftp->th_data[i] > '~')) {
411 				errbuf[i] = '\0';
412 				break;
413 			}
414 			errbuf[i] = tftp->th_data[i];
415 		}
416 		errbuf[SEGSIZE] = '\0';
417 
418 		printf("tftproot: TFTP server returned error %d, %s\n",
419 		    ntohs(tftp->th_code), errbuf);
420 
421 		return -1;
422 		break;
423 	}
424 
425 	default:
426 		DPRINTF(("%s():%d unexpected tftp reply opcode %d\n",
427 		    __func__, __LINE__, ntohs(tftp->th_opcode)));
428 		return -1;
429 		break;
430 	}
431 
432 	/*
433 	 * Check for last packet, which does not fill the whole space
434 	 */
435 	if (m->m_pkthdr.len < hdrlen + SEGSIZE) {
436 		DPRINTF(("%s():%d last chunk (%d bytes)\n",
437 		    __func__, __LINE__, m->m_pkthdr.len));
438 		trh->trh_flags |= TRH_FINISHED;
439 	}
440 
441 
442 	if (ntohs(tftp->th_block) != trh->trh_block) {
443 		DPRINTF(("%s():%d expected block %d, got block %d\n",
444 		    __func__, __LINE__, trh->trh_block, ntohs(tftp->th_block)));
445 		return -1;
446 	}
447 
448 	/*
449 	 * Grow the receiving buffer to accomodate new data
450 	 */
451 	newlen = trh->trh_len + (m->m_pkthdr.len - hdrlen);
452 	if ((trh->trh_base = realloc(trh->trh_base,
453 	    newlen, M_TEMP, M_WAITOK)) == NULL) {
454 		DPRINTF(("%s():%d failed to realloc %ld bytes\n",
455 		    __func__, __LINE__, (long)newlen));
456 		return -1;
457 	}
458 
459 	/*
460 	 * Copy the data
461 	 */
462 	m_copydata(m, hdrlen, m->m_pkthdr.len - hdrlen,
463 		   (char *)trh->trh_base + trh->trh_len);
464 	trh->trh_len = newlen;
465 
466 	return 0;
467 }
468 
469