1 /* 2 * S390 virtio-ccw network boot loading program 3 * 4 * Copyright 2017 Thomas Huth, Red Hat Inc. 5 * 6 * Based on the S390 virtio-ccw loading program (main.c) 7 * Copyright (c) 2013 Alexander Graf <agraf@suse.de> 8 * 9 * And based on the network loading code from SLOF (netload.c) 10 * Copyright (c) 2004, 2008 IBM Corporation 11 * 12 * This code is free software; you can redistribute it and/or modify it 13 * under the terms of the GNU General Public License as published by the 14 * Free Software Foundation; either version 2 of the License, or (at your 15 * option) any later version. 16 */ 17 18 #include <stdint.h> 19 #include <stdbool.h> 20 #include <stdio.h> 21 #include <stdlib.h> 22 #include <string.h> 23 #include <unistd.h> 24 25 #include <tftp.h> 26 #include <ethernet.h> 27 #include <dhcp.h> 28 #include <dhcpv6.h> 29 #include <ipv4.h> 30 #include <ipv6.h> 31 #include <dns.h> 32 #include <time.h> 33 #include <pxelinux.h> 34 35 #include "s390-ccw.h" 36 #include "cio.h" 37 #include "virtio.h" 38 #include "s390-time.h" 39 40 #define DEFAULT_BOOT_RETRIES 10 41 #define DEFAULT_TFTP_RETRIES 20 42 43 extern char _start[]; 44 45 #define KERNEL_ADDR ((void *)0L) 46 #define KERNEL_MAX_SIZE ((long)_start) 47 #define ARCH_COMMAND_LINE_SIZE 896 /* Taken from Linux kernel */ 48 49 /* STSI 3.2.2 offset of first vmdb + offset of uuid inside vmdb */ 50 #define STSI322_VMDB_UUID_OFFSET ((8 + 12) * 4) 51 52 static char cfgbuf[2048]; 53 54 SubChannelId net_schid = { .one = 1 }; 55 static uint8_t mac[6]; 56 static uint64_t dest_timer; 57 58 void set_timer(int val) 59 { 60 dest_timer = get_time_ms() + val; 61 } 62 63 int get_timer(void) 64 { 65 return dest_timer - get_time_ms(); 66 } 67 68 int get_sec_ticks(void) 69 { 70 return 1000; /* number of ticks in 1 second */ 71 } 72 73 /** 74 * Obtain IP and configuration info from DHCP server (either IPv4 or IPv6). 75 * @param fn_ip contains the following configuration information: 76 * client MAC, client IP, TFTP-server MAC, TFTP-server IP, 77 * boot file name 78 * @param retries Number of DHCP attempts 79 * @return 0 : IP and configuration info obtained; 80 * non-0 : error condition occurred. 81 */ 82 static int dhcp(struct filename_ip *fn_ip, int retries) 83 { 84 int i = retries + 1; 85 int rc = -1; 86 87 printf(" Requesting information via DHCP: "); 88 89 dhcpv4_generate_transaction_id(); 90 dhcpv6_generate_transaction_id(); 91 92 do { 93 printf("\b\b\b%03d", i - 1); 94 if (!--i) { 95 printf("\nGiving up after %d DHCP requests\n", retries); 96 return -1; 97 } 98 fn_ip->ip_version = 4; 99 rc = dhcpv4(NULL, fn_ip); 100 if (rc == -1) { 101 fn_ip->ip_version = 6; 102 set_ipv6_address(fn_ip->fd, 0); 103 rc = dhcpv6(NULL, fn_ip); 104 if (rc == 0) { 105 memcpy(&fn_ip->own_ip6, get_ipv6_address(), 16); 106 break; 107 } 108 } 109 if (rc != -1) { /* either success or non-dhcp failure */ 110 break; 111 } 112 } while (1); 113 printf("\b\b\b\bdone\n"); 114 115 return rc; 116 } 117 118 /** 119 * Seed the random number generator with our mac and current timestamp 120 */ 121 static void seed_rng(uint8_t mac[]) 122 { 123 uint64_t seed; 124 125 asm volatile(" stck %0 " : : "Q"(seed) : "memory"); 126 seed ^= (mac[2] << 24) | (mac[3] << 16) | (mac[4] << 8) | mac[5]; 127 srand(seed); 128 } 129 130 static int tftp_load(filename_ip_t *fnip, void *buffer, int len) 131 { 132 tftp_err_t tftp_err; 133 int rc; 134 135 rc = tftp(fnip, buffer, len, DEFAULT_TFTP_RETRIES, &tftp_err); 136 137 if (rc < 0) { 138 /* Make sure that error messages are put into a new line */ 139 printf("\n "); 140 } 141 142 if (rc > 1024) { 143 printf(" TFTP: Received %s (%d KBytes)\n", fnip->filename, rc / 1024); 144 } else if (rc > 0) { 145 printf(" TFTP: Received %s (%d Bytes)\n", fnip->filename, rc); 146 } else { 147 const char *errstr = NULL; 148 int ecode; 149 tftp_get_error_info(fnip, &tftp_err, rc, &errstr, &ecode); 150 printf("TFTP error: %s\n", errstr ? errstr : "unknown error"); 151 } 152 153 return rc; 154 } 155 156 static int net_init(filename_ip_t *fn_ip) 157 { 158 int rc; 159 160 memset(fn_ip, 0, sizeof(filename_ip_t)); 161 162 rc = virtio_net_init(mac); 163 if (rc < 0) { 164 puts("Could not initialize network device"); 165 return -101; 166 } 167 fn_ip->fd = rc; 168 169 printf(" Using MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n", 170 mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]); 171 172 set_mac_address(mac); /* init ethernet layer */ 173 seed_rng(mac); 174 175 rc = dhcp(fn_ip, DEFAULT_BOOT_RETRIES); 176 if (rc >= 0) { 177 if (fn_ip->ip_version == 4) { 178 set_ipv4_address(fn_ip->own_ip); 179 } 180 } else { 181 puts("Could not get IP address"); 182 return -101; 183 } 184 185 if (fn_ip->ip_version == 4) { 186 printf(" Using IPv4 address: %d.%d.%d.%d\n", 187 (fn_ip->own_ip >> 24) & 0xFF, (fn_ip->own_ip >> 16) & 0xFF, 188 (fn_ip->own_ip >> 8) & 0xFF, fn_ip->own_ip & 0xFF); 189 } else if (fn_ip->ip_version == 6) { 190 char ip6_str[40]; 191 ipv6_to_str(fn_ip->own_ip6.addr, ip6_str); 192 printf(" Using IPv6 address: %s\n", ip6_str); 193 } 194 195 if (rc == -2) { 196 printf("ARP request to TFTP server (%d.%d.%d.%d) failed\n", 197 (fn_ip->server_ip >> 24) & 0xFF, (fn_ip->server_ip >> 16) & 0xFF, 198 (fn_ip->server_ip >> 8) & 0xFF, fn_ip->server_ip & 0xFF); 199 return -102; 200 } 201 if (rc == -4 || rc == -3) { 202 puts("Can't obtain TFTP server IP address"); 203 return -107; 204 } 205 206 printf(" Using TFTP server: "); 207 if (fn_ip->ip_version == 4) { 208 printf("%d.%d.%d.%d\n", 209 (fn_ip->server_ip >> 24) & 0xFF, (fn_ip->server_ip >> 16) & 0xFF, 210 (fn_ip->server_ip >> 8) & 0xFF, fn_ip->server_ip & 0xFF); 211 } else if (fn_ip->ip_version == 6) { 212 char ip6_str[40]; 213 ipv6_to_str(fn_ip->server_ip6.addr, ip6_str); 214 printf("%s\n", ip6_str); 215 } 216 217 if (strlen(fn_ip->filename) > 0) { 218 printf(" Bootfile name: '%s'\n", fn_ip->filename); 219 } 220 221 return rc; 222 } 223 224 static void net_release(filename_ip_t *fn_ip) 225 { 226 if (fn_ip->ip_version == 4) { 227 dhcp_send_release(fn_ip->fd); 228 } 229 } 230 231 /** 232 * Retrieve the Universally Unique Identifier of the VM. 233 * @return UUID string, or NULL in case of errors 234 */ 235 static const char *get_uuid(void) 236 { 237 register int r0 asm("0"); 238 register int r1 asm("1"); 239 uint8_t *mem, *buf, uuid[16]; 240 int i, cc, chk = 0; 241 static char uuid_str[37]; 242 243 mem = malloc(2 * PAGE_SIZE); 244 if (!mem) { 245 puts("Out of memory ... can not get UUID."); 246 return NULL; 247 } 248 buf = (uint8_t *)(((uint64_t)mem + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1)); 249 memset(buf, 0, PAGE_SIZE); 250 251 /* Get SYSIB 3.2.2 */ 252 r0 = (3 << 28) | 2; 253 r1 = 2; 254 asm volatile(" stsi 0(%[addr])\n" 255 " ipm %[cc]\n" 256 " srl %[cc],28\n" 257 : [cc] "=d" (cc) 258 : "d" (r0), "d" (r1), [addr] "a" (buf) 259 : "cc", "memory"); 260 if (cc) { 261 free(mem); 262 return NULL; 263 } 264 265 for (i = 0; i < 16; i++) { 266 uuid[i] = buf[STSI322_VMDB_UUID_OFFSET + i]; 267 chk |= uuid[i]; 268 } 269 free(mem); 270 if (!chk) { 271 return NULL; 272 } 273 274 sprintf(uuid_str, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-" 275 "%02x%02x%02x%02x%02x%02x", uuid[0], uuid[1], uuid[2], uuid[3], 276 uuid[4], uuid[5], uuid[6], uuid[7], uuid[8], uuid[9], uuid[10], 277 uuid[11], uuid[12], uuid[13], uuid[14], uuid[15]); 278 279 return uuid_str; 280 } 281 282 /** 283 * Load a kernel with initrd (i.e. with the information that we've got from 284 * a pxelinux.cfg config file) 285 */ 286 static int load_kernel_with_initrd(filename_ip_t *fn_ip, 287 struct pl_cfg_entry *entry) 288 { 289 int rc; 290 291 printf("Loading pxelinux.cfg entry '%s'\n", entry->label); 292 293 if (!entry->kernel) { 294 puts("Kernel entry is missing!\n"); 295 return -1; 296 } 297 298 strncpy(fn_ip->filename, entry->kernel, sizeof(fn_ip->filename)); 299 rc = tftp_load(fn_ip, KERNEL_ADDR, KERNEL_MAX_SIZE); 300 if (rc < 0) { 301 return rc; 302 } 303 304 if (entry->initrd) { 305 uint64_t iaddr = (rc + 0xfff) & ~0xfffUL; 306 307 strncpy(fn_ip->filename, entry->initrd, sizeof(fn_ip->filename)); 308 rc = tftp_load(fn_ip, (void *)iaddr, KERNEL_MAX_SIZE - iaddr); 309 if (rc < 0) { 310 return rc; 311 } 312 /* Patch location and size: */ 313 *(uint64_t *)0x10408 = iaddr; 314 *(uint64_t *)0x10410 = rc; 315 rc += iaddr; 316 } 317 318 if (entry->append) { 319 strncpy((char *)0x10480, entry->append, ARCH_COMMAND_LINE_SIZE); 320 } 321 322 return rc; 323 } 324 325 #define MAX_PXELINUX_ENTRIES 16 326 327 static int net_try_pxelinux_cfg(filename_ip_t *fn_ip) 328 { 329 struct pl_cfg_entry entries[MAX_PXELINUX_ENTRIES]; 330 int num_ent, def_ent = 0; 331 332 num_ent = pxelinux_load_parse_cfg(fn_ip, mac, get_uuid(), 333 DEFAULT_TFTP_RETRIES, 334 cfgbuf, sizeof(cfgbuf), 335 entries, MAX_PXELINUX_ENTRIES, &def_ent); 336 if (num_ent > 0) { 337 return load_kernel_with_initrd(fn_ip, &entries[def_ent]); 338 } 339 340 return -1; 341 } 342 343 /** 344 * Load via information from a .INS file (which can be found on CD-ROMs 345 * for example) 346 */ 347 static int handle_ins_cfg(filename_ip_t *fn_ip, char *cfg, int cfgsize) 348 { 349 char *ptr; 350 int rc = -1, llen; 351 void *destaddr; 352 char *insbuf = cfg; 353 354 ptr = strchr(insbuf, '\n'); 355 if (!ptr) { 356 puts("Does not seem to be a valid .INS file"); 357 return -1; 358 } 359 360 *ptr = 0; 361 printf("\nParsing .INS file:\n %s\n", &insbuf[2]); 362 363 insbuf = ptr + 1; 364 while (*insbuf && insbuf < cfg + cfgsize) { 365 ptr = strchr(insbuf, '\n'); 366 if (ptr) { 367 *ptr = 0; 368 } 369 llen = strlen(insbuf); 370 if (!llen) { 371 insbuf = ptr + 1; 372 continue; 373 } 374 ptr = strchr(insbuf, ' '); 375 if (!ptr) { 376 puts("Missing space separator in .INS file"); 377 return -1; 378 } 379 *ptr = 0; 380 strncpy(fn_ip->filename, insbuf, sizeof(fn_ip->filename)); 381 destaddr = (char *)atol(ptr + 1); 382 rc = tftp_load(fn_ip, destaddr, (long)_start - (long)destaddr); 383 if (rc <= 0) { 384 break; 385 } 386 insbuf += llen + 1; 387 } 388 389 return rc; 390 } 391 392 static int net_try_direct_tftp_load(filename_ip_t *fn_ip) 393 { 394 int rc; 395 void *loadaddr = (void *)0x2000; /* Load right after the low-core */ 396 397 rc = tftp_load(fn_ip, loadaddr, KERNEL_MAX_SIZE - (long)loadaddr); 398 if (rc < 0) { 399 return rc; 400 } else if (rc < 8) { 401 printf("'%s' is too small (%i bytes only).\n", fn_ip->filename, rc); 402 return -1; 403 } 404 405 /* Check whether it is a configuration file instead of a kernel */ 406 if (rc < sizeof(cfgbuf) - 1) { 407 memcpy(cfgbuf, loadaddr, rc); 408 cfgbuf[rc] = 0; /* Make sure that it is NUL-terminated */ 409 if (!strncmp("* ", cfgbuf, 2)) { 410 return handle_ins_cfg(fn_ip, cfgbuf, rc); 411 } 412 /* 413 * pxelinux.cfg support via bootfile name is just here for developers' 414 * convenience (it eases testing with the built-in DHCP server of QEMU 415 * that does not support RFC 5071). The official way to configure a 416 * pxelinux.cfg file name is to use DHCP options 209 and 210 instead. 417 * So only use the pxelinux.cfg parser here for files that start with 418 * a magic comment string. 419 */ 420 if (!strncasecmp("# pxelinux", cfgbuf, 10)) { 421 struct pl_cfg_entry entries[MAX_PXELINUX_ENTRIES]; 422 int num_ent, def_ent = 0; 423 424 num_ent = pxelinux_parse_cfg(cfgbuf, sizeof(cfgbuf), entries, 425 MAX_PXELINUX_ENTRIES, &def_ent); 426 if (num_ent <= 0) { 427 return -1; 428 } 429 return load_kernel_with_initrd(fn_ip, &entries[def_ent]); 430 } 431 } 432 433 /* Move kernel to right location */ 434 memmove(KERNEL_ADDR, loadaddr, rc); 435 436 return rc; 437 } 438 439 static bool find_net_dev(Schib *schib, int dev_no) 440 { 441 int i, r; 442 443 for (i = 0; i < 0x10000; i++) { 444 net_schid.sch_no = i; 445 r = stsch_err(net_schid, schib); 446 if (r == 3 || r == -EIO) { 447 break; 448 } 449 if (!schib->pmcw.dnv) { 450 continue; 451 } 452 enable_subchannel(net_schid); 453 if (!virtio_is_supported(net_schid)) { 454 continue; 455 } 456 if (virtio_get_device_type() != VIRTIO_ID_NET) { 457 continue; 458 } 459 if (dev_no < 0 || schib->pmcw.dev == dev_no) { 460 return true; 461 } 462 } 463 464 return false; 465 } 466 467 static bool virtio_setup(void) 468 { 469 Schib schib; 470 int ssid; 471 bool found = false; 472 uint16_t dev_no; 473 474 /* 475 * We unconditionally enable mss support. In every sane configuration, 476 * this will succeed; and even if it doesn't, stsch_err() can deal 477 * with the consequences. 478 */ 479 enable_mss_facility(); 480 481 if (have_iplb || store_iplb(&iplb)) { 482 IPL_assert(iplb.pbt == S390_IPL_TYPE_CCW, "IPL_TYPE_CCW expected"); 483 dev_no = iplb.ccw.devno; 484 debug_print_int("device no. ", dev_no); 485 net_schid.ssid = iplb.ccw.ssid & 0x3; 486 debug_print_int("ssid ", net_schid.ssid); 487 found = find_net_dev(&schib, dev_no); 488 } else { 489 for (ssid = 0; ssid < 0x3; ssid++) { 490 net_schid.ssid = ssid; 491 found = find_net_dev(&schib, -1); 492 if (found) { 493 break; 494 } 495 } 496 } 497 498 return found; 499 } 500 501 int netmain(void) 502 { 503 filename_ip_t fn_ip; 504 int rc, fnlen; 505 506 sclp_setup(); 507 puts("Network boot starting..."); 508 509 if (!virtio_setup()) { 510 puts("No virtio net device found."); 511 return -1; 512 } 513 514 rc = net_init(&fn_ip); 515 if (rc) { 516 puts("Network initialization failed."); 517 return -1; 518 } 519 520 fnlen = strlen(fn_ip.filename); 521 if (fnlen > 0 && fn_ip.filename[fnlen - 1] != '/') { 522 rc = net_try_direct_tftp_load(&fn_ip); 523 } 524 if (rc <= 0) { 525 rc = net_try_pxelinux_cfg(&fn_ip); 526 } 527 528 net_release(&fn_ip); 529 530 if (rc > 0) { 531 puts("Network loading done, starting kernel..."); 532 jump_to_low_kernel(); 533 } 534 535 puts("Failed to load OS from network."); 536 return -1; 537 } 538