1 /* $NetBSD: subr_tftproot.c,v 1.24 2020/03/07 23:20:19 tnn 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 1.24 2020/03/07 23:20:19 tnn Exp $"); 43 44 #include <sys/param.h> 45 #include <sys/types.h> 46 #include <sys/vnode.h> 47 #include <sys/mount.h> 48 #include <sys/lwp.h> 49 #include <sys/kmem.h> 50 #include <sys/mbuf.h> 51 #include <sys/timevar.h> 52 #include <sys/socketvar.h> 53 54 #include <net/if.h> 55 56 #include <dev/md.h> 57 58 #include <netinet/in.h> 59 60 #include <nfs/rpcv2.h> 61 62 #include <nfs/nfsproto.h> 63 #include <nfs/nfs.h> 64 #include <nfs/nfsmount.h> 65 #include <nfs/nfsdiskless.h> 66 #include <nfs/nfs_var.h> 67 68 /* 69 * Copied from <lib/libsa/tftp.h> 70 */ 71 72 #define SEGSIZE 512 /* data segment size */ 73 74 /* 75 * Packet types. 76 */ 77 #define RRQ 01 /* read request */ 78 #define WRQ 02 /* write request */ 79 #define DATA 03 /* data packet */ 80 #define ACK 04 /* acknowledgement */ 81 #define ERROR 05 /* error code */ 82 83 struct tftphdr { 84 short th_opcode; /* packet type */ 85 union { 86 unsigned short tu_block; /* block # */ 87 short tu_code; /* error code */ 88 char tu_stuff[1]; /* request packet stuff */ 89 } th_u; 90 char th_data[1]; /* data or error string */ 91 } __packed; 92 93 #define th_block th_u.tu_block 94 #define th_code th_u.tu_code 95 #define th_stuff th_u.tu_stuff 96 #define th_msg th_data 97 98 #define IPPORT_TFTP 69 99 100 #ifdef TFTPROOT_DEBUG 101 #define DPRINTF(x) printf x 102 #else 103 #define DPRINTF(x) 104 #endif 105 106 struct tftproot_handle { 107 struct nfs_diskless *trh_nd; 108 void *trh_base; 109 size_t trh_len; 110 unsigned short trh_block; 111 int trh_flags; 112 }; 113 114 #define TRH_FINISHED 1 115 116 int tftproot_dhcpboot(device_t); 117 118 static int tftproot_getfile(struct tftproot_handle *, struct lwp *); 119 static int tftproot_recv(struct mbuf **, void *); 120 121 int 122 tftproot_dhcpboot(device_t bootdv) 123 { 124 struct nfs_diskless *nd = NULL; 125 struct ifnet *ifp = NULL; 126 struct lwp *l; 127 struct tftproot_handle trh; 128 device_t dv; 129 int error = -1; 130 131 if (rootspec != NULL) { 132 int s = pserialize_read_enter(); 133 IFNET_READER_FOREACH(ifp) 134 if (strcmp(rootspec, ifp->if_xname) == 0) 135 break; 136 pserialize_read_exit(s); 137 } 138 139 if ((ifp == NULL) && 140 (bootdv != NULL && device_class(bootdv) == DV_IFNET)) { 141 int s = pserialize_read_enter(); 142 IFNET_READER_FOREACH(ifp) 143 if (strcmp(device_xname(bootdv), ifp->if_xname) == 0) 144 break; 145 pserialize_read_exit(s); 146 } 147 148 if (ifp == NULL) { 149 DPRINTF(("%s():%d ifp is NULL\n", __func__, __LINE__)); 150 goto out; 151 } 152 153 dv = device_find_by_xname(ifp->if_xname); 154 155 if ((dv == NULL) || (device_class(dv) != DV_IFNET)) { 156 DPRINTF(("%s():%d cannot find device for interface %s\n", 157 __func__, __LINE__, ifp->if_xname)); 158 goto out; 159 } 160 161 root_device = dv; 162 163 l = curlwp; /* XXX */ 164 165 nd = kmem_zalloc(sizeof(*nd), KM_SLEEP); 166 nd->nd_ifp = ifp; 167 nd->nd_nomount = 1; 168 169 if ((error = nfs_boot_init(nd, l)) != 0) { 170 DPRINTF(("%s():%d nfs_boot_init returned %d\n", 171 __func__, __LINE__, error)); 172 goto out; 173 } 174 175 /* 176 * Strip leading "tftp:" 177 */ 178 #define PREFIX "tftp:" 179 if (strstr(nd->nd_bootfile, PREFIX) == nd->nd_bootfile) 180 (void)memmove(nd->nd_bootfile, 181 nd->nd_bootfile + (sizeof(PREFIX) - 1), 182 sizeof(nd->nd_bootfile) - sizeof(PREFIX)); 183 #undef PREFIX 184 185 printf("tftproot: bootfile=%s\n", nd->nd_bootfile); 186 187 memset(&trh, 0, sizeof(trh)); 188 trh.trh_nd = nd; 189 trh.trh_block = 1; 190 191 if ((error = tftproot_getfile(&trh, l)) != 0) { 192 DPRINTF(("%s():%d tftproot_getfile returned %d\n", 193 __func__, __LINE__, error)); 194 goto out; 195 } 196 197 error = 0; 198 199 out: 200 if (nd) 201 kmem_free(nd, sizeof(*nd)); 202 203 return error; 204 } 205 206 static int 207 tftproot_getfile(struct tftproot_handle *trh, struct lwp *l) 208 { 209 struct socket *so = NULL; 210 struct mbuf *m_serv = NULL; 211 struct mbuf *m_outbuf = NULL; 212 struct sockaddr_in sin; 213 struct tftphdr *tftp; 214 size_t packetlen, namelen; 215 int error = -1; 216 const char octetstr[] = "octet"; 217 size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data); 218 char *cp; 219 220 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, l, NULL)) != 0) { 221 DPRINTF(("%s():%d socreate returned %d\n", 222 __func__, __LINE__, error)); 223 goto out; 224 } 225 226 /* 227 * Set timeout 228 */ 229 if ((error = nfs_boot_setrecvtimo(so))) { 230 DPRINTF(("%s():%d SO_RCVTIMEO failed %d\n", 231 __func__, __LINE__, error)); 232 goto out; 233 } 234 235 /* 236 * Set server address and port 237 */ 238 memcpy(&sin, &trh->trh_nd->nd_root.ndm_saddr, sizeof(sin)); 239 sin.sin_port = htons(IPPORT_TFTP); 240 241 /* 242 * Set send buffer, prepare the TFTP packet 243 */ 244 namelen = strlen(trh->trh_nd->nd_bootfile) + 1; 245 packetlen = sizeof(tftp->th_opcode) + namelen + sizeof(octetstr); 246 if (packetlen > MSIZE) { 247 DPRINTF(("%s():%d boot filename too long (%ld bytes)\n", 248 __func__, __LINE__, (long)namelen)); 249 error = E2BIG; 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_reset_rcvif(m_outbuf); 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 printf("tftproot: download %s:%s ", 272 inet_ntoa(sin.sin_addr), trh->trh_nd->nd_bootfile); 273 274 do { 275 /* 276 * Show progress for every 200 blocks (100kB) 277 */ 278 #ifndef TFTPROOT_PROGRESS 279 #define TFTPROOT_PROGRESS 200 280 #endif 281 if ((trh->trh_block % TFTPROOT_PROGRESS) == 0) 282 twiddle(); 283 284 /* 285 * Send the packet and receive the answer. 286 * We get the sender address here, which should be 287 * the same server with a different port 288 */ 289 if ((error = nfs_boot_sendrecv(so, &sin, NULL, m_outbuf, 290 tftproot_recv, NULL, &m_serv, trh, l)) != 0) { 291 DPRINTF(("%s():%d sendrecv failed %d\n", 292 __func__, __LINE__, error)); 293 goto out; 294 } 295 296 /* 297 * Accommodate the packet length for acks. 298 * This is really needed only on first pass 299 */ 300 m_outbuf->m_len = hdrlen; 301 m_outbuf->m_pkthdr.len = hdrlen; 302 tftp->th_opcode = htons((short)ACK); 303 tftp->th_block = htons(trh->trh_block); 304 305 306 /* 307 * Check for termination 308 */ 309 if (trh->trh_flags & TRH_FINISHED) 310 break; 311 312 trh->trh_block++; 313 } while (1/* CONSTCOND */); 314 315 printf("\n"); 316 317 /* 318 * Ack the last block. Ignore errors, as we already have the whole 319 * file. 320 */ 321 if ((error = (*so->so_send)(so, mtod(m_serv, struct sockaddr *), NULL, 322 m_outbuf, NULL, 0, l)) != 0) { 323 DPRINTF(("%s():%d tftproot: sosend returned %d\n", 324 __func__, __LINE__, error)); 325 } 326 327 /* Freed by the protocol */ 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); 336 337 error = 0; 338 out: 339 if (m_serv) 340 m_freem(m_serv); 341 342 if (m_outbuf) 343 m_freem(m_outbuf); 344 345 if (so) 346 soclose(so); 347 348 return error; 349 } 350 351 static int 352 tftproot_recv(struct mbuf **mp, void *ctx) 353 { 354 struct tftproot_handle *trh = ctx; 355 struct tftphdr *tftp; 356 struct mbuf *m = *mp; 357 size_t newlen; 358 size_t hdrlen = sizeof(*tftp) - sizeof(tftp->th_data); 359 360 /* 361 * Check for short packet 362 */ 363 if (m->m_pkthdr.len < hdrlen) { 364 DPRINTF(("%s():%d short reply (%d bytes)\n", 365 __func__, __LINE__, m->m_pkthdr.len)); 366 return -1; 367 } 368 369 /* 370 * Check for packet too large for being a TFTP packet 371 */ 372 if (m->m_pkthdr.len > hdrlen + SEGSIZE) { 373 DPRINTF(("%s():%d packet too big (%d bytes)\n", 374 __func__, __LINE__, m->m_pkthdr.len)); 375 return -1; 376 } 377 378 379 /* 380 * Examine the TFTP header 381 */ 382 if (m->m_len > sizeof(*tftp)) { 383 if ((m = *mp = m_pullup(m, sizeof(*tftp))) == NULL) { 384 DPRINTF(("%s():%d m_pullup failed\n", 385 __func__, __LINE__)); 386 return -1; 387 } 388 } 389 tftp = mtod(m, struct tftphdr *); 390 391 /* 392 * We handle data or error 393 */ 394 switch(ntohs(tftp->th_opcode)) { 395 case DATA: 396 break; 397 398 case ERROR: { 399 char errbuf[SEGSIZE + 1]; 400 int i; 401 402 for (i = 0; i < SEGSIZE; i++) { 403 if ((tftp->th_data[i] < ' ') || 404 (tftp->th_data[i] > '~')) { 405 errbuf[i] = '\0'; 406 break; 407 } 408 errbuf[i] = tftp->th_data[i]; 409 } 410 errbuf[SEGSIZE] = '\0'; 411 412 printf("tftproot: TFTP server returned error %d, %s\n", 413 ntohs(tftp->th_code), errbuf); 414 415 return -1; 416 break; 417 } 418 419 default: 420 DPRINTF(("%s():%d unexpected tftp reply opcode %d\n", 421 __func__, __LINE__, ntohs(tftp->th_opcode))); 422 return -1; 423 break; 424 } 425 426 /* 427 * Check for last packet, which does not fill the whole space 428 */ 429 if (m->m_pkthdr.len < hdrlen + SEGSIZE) { 430 DPRINTF(("%s():%d last chunk (%d bytes)\n", 431 __func__, __LINE__, m->m_pkthdr.len)); 432 trh->trh_flags |= TRH_FINISHED; 433 } 434 435 436 if (ntohs(tftp->th_block) != trh->trh_block) { 437 DPRINTF(("%s():%d expected block %d, got block %d\n", 438 __func__, __LINE__, trh->trh_block, ntohs(tftp->th_block))); 439 return -1; 440 } 441 442 /* 443 * Grow the receiving buffer to accommodate new data 444 */ 445 newlen = trh->trh_len + (m->m_pkthdr.len - hdrlen); 446 if ((trh->trh_base = realloc(trh->trh_base, 447 newlen, M_TEMP, M_WAITOK)) == NULL) { 448 DPRINTF(("%s():%d failed to realloc %ld bytes\n", 449 __func__, __LINE__, (long)newlen)); 450 return -1; 451 } 452 453 /* 454 * Copy the data 455 */ 456 m_copydata(m, hdrlen, m->m_pkthdr.len - hdrlen, 457 (char *)trh->trh_base + trh->trh_len); 458 trh->trh_len = newlen; 459 460 return 0; 461 } 462 463