1 /* 2 * Copyright (c) 1998 Robert Nordier 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 18 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 19 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 20 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 21 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 22 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 23 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 24 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #ifndef lint 28 static const char rcsid[] = 29 "$FreeBSD$"; 30 #endif /* not lint */ 31 32 #include <sys/param.h> 33 #include <sys/stat.h> 34 #include <sys/mman.h> 35 36 #include <err.h> 37 #include <errno.h> 38 #include <fcntl.h> 39 #include <stdarg.h> 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <unistd.h> 44 45 #include "a.out.h" 46 #include "btx.h" 47 #include "elfh.h" 48 49 #define BTX_PATH "/sys/boot/i386/btx" 50 51 #define I_LDR 0 /* BTX loader */ 52 #define I_BTX 1 /* BTX kernel */ 53 #define I_CLNT 2 /* Client program */ 54 55 #define F_BIN 0 /* Binary */ 56 #define F_AOUT 1 /* ZMAGIC a.out */ 57 #define F_ELF 2 /* 32-bit ELF */ 58 #define F_CNT 3 /* Number of formats */ 59 60 #define IMPURE 1 /* Writable text */ 61 #define MAXU32 0xffffffff /* Maximum unsigned 32-bit quantity */ 62 63 #define align(x, y) (((x) + (y) - 1) & ~((y) - 1)) 64 65 struct hdr { 66 uint32_t fmt; /* Format */ 67 uint32_t flags; /* Bit flags */ 68 uint32_t size; /* Size of file */ 69 uint32_t text; /* Size of text segment */ 70 uint32_t data; /* Size of data segment */ 71 uint32_t bss; /* Size of bss segment */ 72 uint32_t org; /* Program origin */ 73 uint32_t entry; /* Program entry point */ 74 }; 75 76 static const char *const fmtlist[] = {"bin", "aout", "elf"}; 77 78 static const char binfo[] = 79 "kernel: ver=%u.%02u size=%x load=%x entry=%x map=%uM " 80 "pgctl=%x:%x\n"; 81 static const char cinfo[] = 82 "client: fmt=%s size=%x text=%x data=%x bss=%x entry=%x\n"; 83 static const char oinfo[] = 84 "output: fmt=%s size=%x text=%x data=%x org=%x entry=%x\n"; 85 86 static const char *lname = 87 BTX_PATH "/btxldr/btxldr"; /* BTX loader */ 88 static const char *bname = 89 BTX_PATH "/btx/btx"; /* BTX kernel */ 90 static const char *oname = 91 "a.out"; /* Output filename */ 92 93 static int ppage = -1; /* First page present */ 94 static int wpage = -1; /* First page writable */ 95 96 static unsigned int format; /* Output format */ 97 98 static uint32_t centry; /* Client entry address */ 99 static uint32_t lentry; /* Loader entry address */ 100 101 static int Eflag; /* Client entry option */ 102 103 static int quiet; /* Inhibit warnings */ 104 static int verbose; /* Display information */ 105 106 static const char *tname; /* Temporary output file */ 107 static const char *fname; /* Current input file */ 108 109 static void cleanup(void); 110 static void btxld(const char *); 111 static void getbtx(int, struct btx_hdr *); 112 static void gethdr(int, struct hdr *); 113 static void puthdr(int, struct hdr *); 114 static void copy(int, int, size_t, off_t); 115 static size_t readx(int, void *, size_t, off_t); 116 static void writex(int, const void *, size_t); 117 static void seekx(int, off_t); 118 static unsigned int optfmt(const char *); 119 static uint32_t optaddr(const char *); 120 static int optpage(const char *, int); 121 static void Warn(const char *, const char *, ...); 122 static void usage(void); 123 124 /* 125 * A link editor for BTX clients. 126 */ 127 int 128 main(int argc, char *argv[]) 129 { 130 int c; 131 132 while ((c = getopt(argc, argv, "qvb:E:e:f:l:o:P:W:")) != -1) 133 switch (c) { 134 case 'q': 135 quiet = 1; 136 break; 137 case 'v': 138 verbose = 1; 139 break; 140 case 'b': 141 bname = optarg; 142 break; 143 case 'E': 144 centry = optaddr(optarg); 145 Eflag = 1; 146 break; 147 case 'e': 148 lentry = optaddr(optarg); 149 break; 150 case 'f': 151 format = optfmt(optarg); 152 break; 153 case 'l': 154 lname = optarg; 155 break; 156 case 'o': 157 oname = optarg; 158 break; 159 case 'P': 160 ppage = optpage(optarg, 1); 161 break; 162 case 'W': 163 wpage = optpage(optarg, BTX_MAXCWR); 164 break; 165 default: 166 usage(); 167 } 168 argc -= optind; 169 argv += optind; 170 if (argc != 1) 171 usage(); 172 atexit(cleanup); 173 btxld(*argv); 174 return 0; 175 } 176 177 /* 178 * Clean up after errors. 179 */ 180 static void 181 cleanup(void) 182 { 183 if (tname) 184 remove(tname); 185 } 186 187 /* 188 * Read the input files; write the output file; display information. 189 */ 190 static void 191 btxld(const char *iname) 192 { 193 char name[FILENAME_MAX]; 194 struct btx_hdr btx; 195 struct hdr ihdr, ohdr; 196 unsigned int ldr_size, cwr; 197 int fdi[3], fdo, i; 198 199 ldr_size = 0; 200 201 for (i = I_LDR; i <= I_CLNT; i++) { 202 fname = i == I_LDR ? lname : i == I_BTX ? bname : iname; 203 if ((fdi[i] = open(fname, O_RDONLY)) == -1) 204 err(2, "%s", fname); 205 switch (i) { 206 case I_LDR: 207 gethdr(fdi[i], &ihdr); 208 if (ihdr.fmt != F_BIN) 209 Warn(fname, "Loader format is %s; processing as %s", 210 fmtlist[ihdr.fmt], fmtlist[F_BIN]); 211 ldr_size = ihdr.size; 212 break; 213 case I_BTX: 214 getbtx(fdi[i], &btx); 215 break; 216 case I_CLNT: 217 gethdr(fdi[i], &ihdr); 218 if (ihdr.org && ihdr.org != BTX_PGSIZE) 219 Warn(fname, 220 "Client origin is 0x%x; expecting 0 or 0x%x", 221 ihdr.org, BTX_PGSIZE); 222 } 223 } 224 memset(&ohdr, 0, sizeof(ohdr)); 225 ohdr.fmt = format; 226 ohdr.text = ldr_size; 227 ohdr.data = btx.btx_textsz + ihdr.size; 228 ohdr.org = lentry; 229 ohdr.entry = lentry; 230 cwr = 0; 231 if (wpage > 0 || (wpage == -1 && !(ihdr.flags & IMPURE))) { 232 if (wpage > 0) 233 cwr = wpage; 234 else { 235 cwr = howmany(ihdr.text, BTX_PGSIZE); 236 if (cwr > BTX_MAXCWR) 237 cwr = BTX_MAXCWR; 238 } 239 } 240 if (ppage > 0 || (ppage && wpage && ihdr.org >= BTX_PGSIZE)) { 241 btx.btx_flags |= BTX_MAPONE; 242 if (!cwr) 243 cwr++; 244 } 245 btx.btx_pgctl -= cwr; 246 btx.btx_entry = Eflag ? centry : ihdr.entry; 247 if (snprintf(name, sizeof(name), "%s.tmp", oname) >= sizeof(name)) 248 errx(2, "%s: Filename too long", oname); 249 if ((fdo = open(name, O_CREAT | O_TRUNC | O_WRONLY, 0666)) == -1) 250 err(2, "%s", name); 251 if (!(tname = strdup(name))) 252 err(2, NULL); 253 puthdr(fdo, &ohdr); 254 for (i = I_LDR; i <= I_CLNT; i++) { 255 fname = i == I_LDR ? lname : i == I_BTX ? bname : iname; 256 switch (i) { 257 case I_LDR: 258 copy(fdi[i], fdo, ldr_size, 0); 259 seekx(fdo, ohdr.size += ohdr.text); 260 break; 261 case I_BTX: 262 writex(fdo, &btx, sizeof(btx)); 263 copy(fdi[i], fdo, btx.btx_textsz - sizeof(btx), 264 sizeof(btx)); 265 break; 266 case I_CLNT: 267 copy(fdi[i], fdo, ihdr.size, 0); 268 if (ftruncate(fdo, ohdr.size += ohdr.data)) 269 err(2, "%s", tname); 270 } 271 if (close(fdi[i])) 272 err(2, "%s", fname); 273 } 274 if (close(fdo)) 275 err(2, "%s", tname); 276 if (rename(tname, oname)) 277 err(2, "%s: Can't rename to %s", tname, oname); 278 tname = NULL; 279 if (verbose) { 280 printf(binfo, btx.btx_majver, btx.btx_minver, btx.btx_textsz, 281 BTX_ORIGIN(btx), BTX_ENTRY(btx), BTX_MAPPED(btx) * 282 BTX_PGSIZE / 0x100000, !!(btx.btx_flags & BTX_MAPONE), 283 BTX_MAPPED(btx) - btx.btx_pgctl - BTX_PGBASE / 284 BTX_PGSIZE - BTX_MAPPED(btx) * 4 / BTX_PGSIZE); 285 printf(cinfo, fmtlist[ihdr.fmt], ihdr.size, ihdr.text, 286 ihdr.data, ihdr.bss, ihdr.entry); 287 printf(oinfo, fmtlist[ohdr.fmt], ohdr.size, ohdr.text, 288 ohdr.data, ohdr.org, ohdr.entry); 289 } 290 } 291 292 /* 293 * Read BTX file header. 294 */ 295 static void 296 getbtx(int fd, struct btx_hdr * btx) 297 { 298 if (readx(fd, btx, sizeof(*btx), 0) != sizeof(*btx) || 299 btx->btx_magic[0] != BTX_MAG0 || 300 btx->btx_magic[1] != BTX_MAG1 || 301 btx->btx_magic[2] != BTX_MAG2) 302 errx(1, "%s: Not a BTX kernel", fname); 303 } 304 305 /* 306 * Get file size and read a.out or ELF header. 307 */ 308 static void 309 gethdr(int fd, struct hdr *hdr) 310 { 311 struct stat sb; 312 const struct exec *ex; 313 const Elf32_Ehdr *ee; 314 const Elf32_Phdr *ep; 315 void *p; 316 unsigned int fmt, x, n, i; 317 318 memset(hdr, 0, sizeof(*hdr)); 319 if (fstat(fd, &sb)) 320 err(2, "%s", fname); 321 if (sb.st_size > MAXU32) 322 errx(1, "%s: Too big", fname); 323 hdr->size = sb.st_size; 324 if ((p = mmap(NULL, hdr->size, PROT_READ, MAP_SHARED, fd, 325 0)) == MAP_FAILED) 326 err(2, "%s", fname); 327 for (fmt = F_CNT - 1; !hdr->fmt && fmt; fmt--) 328 switch (fmt) { 329 case F_AOUT: 330 ex = p; 331 if (hdr->size >= sizeof(struct exec) && !N_BADMAG(*ex)) { 332 hdr->fmt = fmt; 333 x = N_GETMAGIC(*ex); 334 if (x == OMAGIC || x == NMAGIC) { 335 if (x == NMAGIC) 336 Warn(fname, "Treating %s NMAGIC as OMAGIC", 337 fmtlist[fmt]); 338 hdr->flags |= IMPURE; 339 } 340 hdr->text = ex->a_text; 341 hdr->data = ex->a_data; 342 hdr->bss = ex->a_bss; 343 hdr->entry = ex->a_entry; 344 if (ex->a_entry >= BTX_PGSIZE) 345 hdr->org = BTX_PGSIZE; 346 } 347 break; 348 case F_ELF: 349 ee = p; 350 if (hdr->size >= sizeof(Elf32_Ehdr) && IS_ELF(*ee)) { 351 hdr->fmt = fmt; 352 for (n = i = 0; i < ee->e_phnum; i++) { 353 ep = (void *)((uint8_t *)p + ee->e_phoff + 354 ee->e_phentsize * i); 355 if (ep->p_type == PT_LOAD) 356 switch (n++) { 357 case 0: 358 hdr->text = ep->p_filesz; 359 hdr->org = ep->p_paddr; 360 if (ep->p_flags & PF_W) 361 hdr->flags |= IMPURE; 362 break; 363 case 1: 364 hdr->data = ep->p_filesz; 365 hdr->bss = ep->p_memsz - ep->p_filesz; 366 break; 367 case 2: 368 Warn(fname, 369 "Ignoring extra %s PT_LOAD segments", 370 fmtlist[fmt]); 371 } 372 } 373 hdr->entry = ee->e_entry; 374 } 375 } 376 if (munmap(p, hdr->size)) 377 err(2, "%s", fname); 378 } 379 380 /* 381 * Write a.out or ELF header. 382 */ 383 static void 384 puthdr(int fd, struct hdr *hdr) 385 { 386 struct exec ex; 387 struct elfh eh; 388 389 switch (hdr->fmt) { 390 case F_AOUT: 391 memset(&ex, 0, sizeof(ex)); 392 N_SETMAGIC(ex, ZMAGIC, MID_ZERO, 0); 393 hdr->text = N_ALIGN(ex, hdr->text); 394 ex.a_text = hdr->text; 395 hdr->data = N_ALIGN(ex, hdr->data); 396 ex.a_data = hdr->data; 397 ex.a_entry = hdr->entry; 398 writex(fd, &ex, sizeof(ex)); 399 hdr->size = N_ALIGN(ex, sizeof(ex)); 400 seekx(fd, hdr->size); 401 break; 402 case F_ELF: 403 eh = elfhdr; 404 eh.e.e_entry = hdr->entry; 405 eh.p[0].p_vaddr = eh.p[0].p_paddr = hdr->org; 406 eh.p[0].p_filesz = eh.p[0].p_memsz = hdr->text; 407 eh.p[1].p_offset = eh.p[0].p_offset + eh.p[0].p_filesz; 408 eh.p[1].p_vaddr = eh.p[1].p_paddr = align(eh.p[0].p_paddr + 409 eh.p[0].p_memsz, 4); 410 eh.p[1].p_filesz = eh.p[1].p_memsz = hdr->data; 411 eh.sh[2].sh_addr = eh.p[0].p_vaddr; 412 eh.sh[2].sh_offset = eh.p[0].p_offset; 413 eh.sh[2].sh_size = eh.p[0].p_filesz; 414 eh.sh[3].sh_addr = eh.p[1].p_vaddr; 415 eh.sh[3].sh_offset = eh.p[1].p_offset; 416 eh.sh[3].sh_size = eh.p[1].p_filesz; 417 writex(fd, &eh, sizeof(eh)); 418 hdr->size = sizeof(eh); 419 } 420 } 421 422 /* 423 * Safe copy from input file to output file. 424 */ 425 static void 426 copy(int fdi, int fdo, size_t nbyte, off_t offset) 427 { 428 char buf[8192]; 429 size_t n; 430 431 while (nbyte) { 432 if ((n = sizeof(buf)) > nbyte) 433 n = nbyte; 434 if (readx(fdi, buf, n, offset) != n) 435 errx(2, "%s: Short read", fname); 436 writex(fdo, buf, n); 437 nbyte -= n; 438 offset = -1; 439 } 440 } 441 442 /* 443 * Safe read from input file. 444 */ 445 static size_t 446 readx(int fd, void *buf, size_t nbyte, off_t offset) 447 { 448 ssize_t n; 449 450 if (offset != -1 && lseek(fd, offset, SEEK_SET) != offset) 451 err(2, "%s", fname); 452 if ((n = read(fd, buf, nbyte)) == -1) 453 err(2, "%s", fname); 454 return n; 455 } 456 457 /* 458 * Safe write to output file. 459 */ 460 static void 461 writex(int fd, const void *buf, size_t nbyte) 462 { 463 ssize_t n; 464 465 if ((n = write(fd, buf, nbyte)) == -1) 466 err(2, "%s", tname); 467 if (n != nbyte) 468 errx(2, "%s: Short write", tname); 469 } 470 471 /* 472 * Safe seek in output file. 473 */ 474 static void 475 seekx(int fd, off_t offset) 476 { 477 if (lseek(fd, offset, SEEK_SET) != offset) 478 err(2, "%s", tname); 479 } 480 481 /* 482 * Convert an option argument to a format code. 483 */ 484 static unsigned int 485 optfmt(const char *arg) 486 { 487 unsigned int i; 488 489 for (i = 0; i < F_CNT && strcmp(arg, fmtlist[i]); i++); 490 if (i == F_CNT) 491 errx(1, "%s: Unknown format", arg); 492 return i; 493 } 494 495 /* 496 * Convert an option argument to an address. 497 */ 498 static uint32_t 499 optaddr(const char *arg) 500 { 501 char *s; 502 unsigned long x; 503 504 errno = 0; 505 x = strtoul(arg, &s, 0); 506 if (errno || !*arg || *s || x > MAXU32) 507 errx(1, "%s: Illegal address", arg); 508 return x; 509 } 510 511 /* 512 * Convert an option argument to a page number. 513 */ 514 static int 515 optpage(const char *arg, int hi) 516 { 517 char *s; 518 long x; 519 520 errno = 0; 521 x = strtol(arg, &s, 0); 522 if (errno || !*arg || *s || x < 0 || x > hi) 523 errx(1, "%s: Illegal page number", arg); 524 return x; 525 } 526 527 /* 528 * Display a warning. 529 */ 530 static void 531 Warn(const char *locus, const char *fmt, ...) 532 { 533 va_list ap; 534 char *s; 535 536 if (!quiet) { 537 asprintf(&s, "%s: Warning: %s", locus, fmt); 538 va_start(ap, fmt); 539 vwarnx(s, ap); 540 va_end(ap); 541 free(s); 542 } 543 } 544 545 /* 546 * Display usage information. 547 */ 548 static void 549 usage(void) 550 { 551 fprintf(stderr, "%s\n%s\n", 552 "usage: btxld [-qv] [-b file] [-E address] [-e address] [-f format]", 553 " [-l file] [-o filename] [-P page] [-W page] file"); 554 exit(1); 555 } 556