usr/src/tools/btxld/btxld.c

   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 #include <sys/param.h>
  28 #include "endian.h"
  29 #include <sys/stat.h>
  30 #include <sys/mman.h>
  31
  32 /* XXX make this work as an i386/amd64 cross-tool */
  33 #undef __LDPGSZ
  34 #define __LDPGSZ        4096
  35
  36 #include <netinet/in.h>
  37
  38 #include "imgact_aout.h"
  39 #include <err.h>
  40 #include <errno.h>
  41 #include <fcntl.h>
  42 #include <stdarg.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46 #include <unistd.h>
  47
  48 #include "btx.h"
  49 #include "elfh.h"
  50
  51 #define BTX_PATH                "/sys/boot/i386/btx"
  52
  53 #define I_LDR   0               /* BTX loader */
  54 #define I_BTX   1               /* BTX kernel */
  55 #define I_CLNT  2               /* Client program */
  56
  57 #define F_BIN   0               /* Binary */
  58 #define F_AOUT  1               /* ZMAGIC a.out */
  59 #define F_ELF   2               /* 32-bit ELF */
  60 #define F_CNT   3               /* Number of formats */
  61
  62 #define IMPURE  1               /* Writable text */
  63 #define MAXU32  0xffffffff      /* Maximum unsigned 32-bit quantity */
  64
  65 #define align(x, y) (((x) + (y) - 1) & ~((y) - 1))
  66
  67 struct hdr {
  68     uint32_t fmt;               /* Format */
  69     uint32_t flags;             /* Bit flags */
  70     uint32_t size;              /* Size of file */
  71     uint32_t text;              /* Size of text segment */
  72     uint32_t data;              /* Size of data segment */
  73     uint32_t bss;               /* Size of bss segment */
  74     uint32_t org;               /* Program origin */
  75     uint32_t entry;             /* Program entry point */
  76 };
  77
  78 static const char *const fmtlist[] = {"bin", "aout", "elf"};
  79
  80 static const char binfo[] =
  81     "kernel: ver=%u.%02u size=%x load=%x entry=%x map=%uM "
  82     "pgctl=%x:%x\n";
  83 static const char cinfo[] =
  84     "client: fmt=%s size=%x text=%x data=%x bss=%x entry=%x\n";
  85 static const char oinfo[] =
  86     "output: fmt=%s size=%x text=%x data=%x org=%x entry=%x\n";
  87
  88 static const char *lname =
  89     BTX_PATH "/btxldr/btxldr";  /* BTX loader */
  90 static const char *bname =
  91     BTX_PATH "/btx/btx";        /* BTX kernel */
  92 static const char *oname =
  93     "a.out";                    /* Output filename */
  94
  95 static int ppage = -1;          /* First page present */
  96 static int wpage = -1;          /* First page writable */
  97
  98 static unsigned int format;     /* Output format */
  99
 100 static uint32_t centry;         /* Client entry address */
 101 static uint32_t lentry;         /* Loader entry address */
 102
 103 static int Eflag;               /* Client entry option */
 104
 105 static int quiet;               /* Inhibit warnings */
 106 static int verbose;             /* Display information */
 107
 108 static const char *tname;       /* Temporary output file */
 109 static const char *fname;       /* Current input file */
 110
 111 static void cleanup(void);
 112 static void btxld(const char *);
 113 static void getbtx(int, struct btx_hdr *);
 114 static void gethdr(int, struct hdr *);
 115 static void puthdr(int, struct hdr *);
 116 static void copy(int, int, size_t, off_t);
 117 static size_t readx(int, void *, size_t, off_t);
 118 static void writex(int, const void *, size_t);
 119 static void seekx(int, off_t);
 120 static unsigned int optfmt(const char *);
 121 static uint32_t optaddr(const char *);
 122 static int optpage(const char *, int);
 123 static void Warn(const char *, const char *, ...);
 124 static void usage(void);
 125 extern void add_version(const char *, char *);
 126
 127 /*
 128  * A link editor for BTX clients.
 129  */
 130 int
 131 main(int argc, char *argv[])
 132 {
 133     int c;
 134     char *version = NULL;
 135
 136     while ((c = getopt(argc, argv, "qvb:E:e:f:l:o:P:V:W:")) != -1)
 137         switch (c) {
 138         case 'q':
 139             quiet = 1;
 140             break;
 141         case 'v':
 142             verbose = 1;
 143             break;
 144         case 'b':
 145             bname = optarg;
 146             break;
 147         case 'E':
 148             centry = optaddr(optarg);
 149             Eflag = 1;
 150             break;
 151         case 'e':
 152             lentry = optaddr(optarg);
 153             break;
 154         case 'f':
 155             format = optfmt(optarg);
 156             break;
 157         case 'l':
 158             lname = optarg;
 159             break;
 160         case 'o':
 161             oname = optarg;
 162             break;
 163         case 'P':
 164             ppage = optpage(optarg, 1);
 165             break;
 166         case 'V':
 167             version = optarg;
 168             break;
 169         case 'W':
 170             wpage = optpage(optarg, BTX_MAXCWR);
 171             break;
 172         default:
 173             usage();
 174         }
 175     argc -= optind;
 176     argv += optind;
 177     if (argc != 1)
 178         usage();
 179     atexit(cleanup);
 180     btxld(*argv);
 181     if (version != NULL)
 182         add_version(oname, version);
 183     return 0;
 184 }
 185
 186 /*
 187  * Clean up after errors.
 188  */
 189 static void
 190 cleanup(void)
 191 {
 192     if (tname)
 193         (void) remove(tname);
 194 }
 195
 196 /*
 197  * Read the input files; write the output file; display information.
 198  */
 199 static void
 200 btxld(const char *iname)
 201 {
 202     char name[FILENAME_MAX];
 203     struct btx_hdr btx, btxle;
 204     struct hdr ihdr, ohdr;
 205     unsigned int ldr_size, cwr;
 206     int fdi[3], fdo, i;
 207
 208     ldr_size = 0;
 209
 210     for (i = I_LDR; i <= I_CLNT; i++) {
 211         fname = i == I_LDR ? lname : i == I_BTX ? bname : iname;
 212         if ((fdi[i] = open(fname, O_RDONLY)) == -1)
 213             err(2, "%s", fname);
 214         switch (i) {
 215         case I_LDR:
 216             gethdr(fdi[i], &ihdr);
 217             if (ihdr.fmt != F_BIN)
 218                 Warn(fname, "Loader format is %s; processing as %s",
 219                      fmtlist[ihdr.fmt], fmtlist[F_BIN]);
 220             ldr_size = ihdr.size;
 221             break;
 222         case I_BTX:
 223             getbtx(fdi[i], &btx);
 224             break;
 225         case I_CLNT:
 226             gethdr(fdi[i], &ihdr);
 227             if (ihdr.org && ihdr.org != BTX_PGSIZE)
 228                 Warn(fname,
 229                      "Client origin is 0x%x; expecting 0 or 0x%x",
 230                      ihdr.org, BTX_PGSIZE);
 231         }
 232     }
 233     memset(&ohdr, 0, sizeof(ohdr));
 234     ohdr.fmt = format;
 235     ohdr.text = ldr_size;
 236     ohdr.data = btx.btx_textsz + ihdr.size;
 237     ohdr.org = lentry;
 238     ohdr.entry = lentry;
 239     cwr = 0;
 240     if (wpage > 0 || (wpage == -1 && !(ihdr.flags & IMPURE))) {
 241         if (wpage > 0)
 242             cwr = wpage;
 243         else {
 244             cwr = howmany(ihdr.text, BTX_PGSIZE);
 245             if (cwr > BTX_MAXCWR)
 246                 cwr = BTX_MAXCWR;
 247         }
 248     }
 249     if (ppage > 0 || (ppage && wpage && ihdr.org >= BTX_PGSIZE)) {
 250         btx.btx_flags |= BTX_MAPONE;
 251         if (!cwr)
 252             cwr++;
 253     }
 254     btx.btx_pgctl -= cwr;
 255     btx.btx_entry = Eflag ? centry : ihdr.entry;
 256     if ((size_t)snprintf(name, sizeof(name), "%s.tmp", oname) >= sizeof(name))
 257         errx(2, "%s: Filename too long", oname);
 258     if ((fdo = open(name, O_CREAT | O_TRUNC | O_WRONLY, 0666)) == -1)
 259         err(2, "%s", name);
 260     if (!(tname = strdup(name)))
 261         err(2, NULL);
 262     puthdr(fdo, &ohdr);
 263     for (i = I_LDR; i <= I_CLNT; i++) {
 264         fname = i == I_LDR ? lname : i == I_BTX ? bname : iname;
 265         switch (i) {
 266         case I_LDR:
 267             copy(fdi[i], fdo, ldr_size, 0);
 268             seekx(fdo, ohdr.size += ohdr.text);
 269             break;
 270         case I_BTX:
 271             btxle = btx;
 272             btxle.btx_pgctl = htole16(btxle.btx_pgctl);
 273             btxle.btx_textsz = htole16(btxle.btx_textsz);
 274             btxle.btx_entry = htole32(btxle.btx_entry);
 275             writex(fdo, &btxle, sizeof(btxle));
 276             copy(fdi[i], fdo, btx.btx_textsz - sizeof(btx),
 277                  sizeof(btx));
 278             break;
 279         case I_CLNT:
 280             copy(fdi[i], fdo, ihdr.size, 0);
 281             if (ftruncate(fdo, ohdr.size += ohdr.data))
 282                 err(2, "%s", tname);
 283         }
 284         if (close(fdi[i]))
 285             err(2, "%s", fname);
 286     }
 287     if (close(fdo))
 288         err(2, "%s", tname);
 289     if (rename(tname, oname))
 290         err(2, "%s: Can't rename to %s", tname, oname);
 291     free((void *)(intptr_t)tname);
 292     tname = NULL;
 293     if (verbose) {
 294         printf(binfo, btx.btx_majver, btx.btx_minver, btx.btx_textsz,
 295                BTX_ORIGIN(btx), BTX_ENTRY(btx), BTX_MAPPED(btx) *
 296                BTX_PGSIZE / 0x100000, !!(btx.btx_flags & BTX_MAPONE),
 297                BTX_MAPPED(btx) - btx.btx_pgctl - BTX_PGBASE /
 298                BTX_PGSIZE - BTX_MAPPED(btx) * 4 / BTX_PGSIZE);
 299         printf(cinfo, fmtlist[ihdr.fmt], ihdr.size, ihdr.text,
 300                ihdr.data, ihdr.bss, ihdr.entry);
 301         printf(oinfo, fmtlist[ohdr.fmt], ohdr.size, ohdr.text,
 302                ohdr.data, ohdr.org, ohdr.entry);
 303     }
 304 }
 305
 306 /*
 307  * Read BTX file header.
 308  */
 309 static void
 310 getbtx(int fd, struct btx_hdr * btx)
 311 {
 312     if (readx(fd, btx, sizeof(*btx), 0) != sizeof(*btx) ||
 313         btx->btx_magic[0] != BTX_MAG0 ||
 314         btx->btx_magic[1] != BTX_MAG1 ||
 315         btx->btx_magic[2] != BTX_MAG2)
 316         errx(1, "%s: Not a BTX kernel", fname);
 317     btx->btx_pgctl = le16toh(btx->btx_pgctl);
 318     btx->btx_textsz = le16toh(btx->btx_textsz);
 319     btx->btx_entry = le32toh(btx->btx_entry);
 320 }
 321
 322 /*
 323  * Get file size and read a.out or ELF header.
 324  */
 325 static void
 326 gethdr(int fd, struct hdr *hdr)
 327 {
 328     struct stat sb;
 329     const struct exec *ex;
 330     const Elf32_Ehdr *ee;
 331     const Elf32_Phdr *ep;
 332     void *p;
 333     unsigned int fmt, x, n, i;
 334
 335     memset(hdr, 0, sizeof(*hdr));
 336     if (fstat(fd, &sb))
 337         err(2, "%s", fname);
 338     if (sb.st_size > MAXU32)
 339         errx(1, "%s: Too big", fname);
 340     hdr->size = sb.st_size;
 341     if (!hdr->size)
 342         return;
 343     if ((p = mmap(NULL, hdr->size, PROT_READ, MAP_SHARED, fd,
 344                   0)) == MAP_FAILED)
 345         err(2, "%s", fname);
 346     for (fmt = F_CNT - 1; !hdr->fmt && fmt; fmt--)
 347         switch (fmt) {
 348         case F_AOUT:
 349             ex = p;
 350             if (hdr->size >= sizeof(struct exec) && !N_BADMAG(*ex)) {
 351                 hdr->fmt = fmt;
 352                 x = N_GETMAGIC(*ex);
 353                 if (x == OMAGIC || x == NMAGIC) {
 354                     if (x == NMAGIC)
 355                         Warn(fname, "Treating %s NMAGIC as OMAGIC",
 356                              fmtlist[fmt]);
 357                     hdr->flags |= IMPURE;
 358                 }
 359                 hdr->text = le32toh(ex->a_text);
 360                 hdr->data = le32toh(ex->a_data);
 361                 hdr->bss = le32toh(ex->a_bss);
 362                 hdr->entry = le32toh(ex->a_entry);
 363                 if (le32toh(ex->a_entry) >= BTX_PGSIZE)
 364                     hdr->org = BTX_PGSIZE;
 365             }
 366             break;
 367         case F_ELF:
 368             ee = p;
 369             if (hdr->size >= sizeof(Elf32_Ehdr) && IS_ELF(*ee)) {
 370                 hdr->fmt = fmt;
 371                 for (n = i = 0; i < le16toh(ee->e_phnum); i++) {
 372                     ep = (void *)((uint8_t *)p + le32toh(ee->e_phoff) +
 373                                   le16toh(ee->e_phentsize) * i);
 374                     if (le32toh(ep->p_type) == PT_LOAD)
 375                         switch (n++) {
 376                         case 0:
 377                             hdr->text = le32toh(ep->p_filesz);
 378                             hdr->org = le32toh(ep->p_paddr);
 379                             if (le32toh(ep->p_flags) & PF_W)
 380                                 hdr->flags |= IMPURE;
 381                             break;
 382                         case 1:
 383                             hdr->data = le32toh(ep->p_filesz);
 384                             hdr->bss = le32toh(ep->p_memsz) -
 385                                 le32toh(ep->p_filesz);
 386                             break;
 387                         case 2:
 388                             Warn(fname,
 389                                  "Ignoring extra %s PT_LOAD segments",
 390                                  fmtlist[fmt]);
 391                         }
 392                 }
 393                 hdr->entry = le32toh(ee->e_entry);
 394             }
 395         }
 396     if (munmap(p, hdr->size))
 397         err(2, "%s", fname);
 398 }
 399
 400 /*
 401  * Write a.out or ELF header.
 402  */
 403 static void
 404 puthdr(int fd, struct hdr *hdr)
 405 {
 406     struct exec ex;
 407     struct elfh eh;
 408
 409     switch (hdr->fmt) {
 410     case F_AOUT:
 411         memset(&ex, 0, sizeof(ex));
 412         N_SETMAGIC(ex, ZMAGIC, MID_I386, 0);
 413         hdr->text = N_ALIGN(ex, hdr->text);
 414         ex.a_text = htole32(hdr->text);
 415         hdr->data = N_ALIGN(ex, hdr->data);
 416         ex.a_data = htole32(hdr->data);
 417         ex.a_entry = htole32(hdr->entry);
 418         writex(fd, &ex, sizeof(ex));
 419         hdr->size = N_ALIGN(ex, sizeof(ex));
 420         seekx(fd, hdr->size);
 421         break;
 422     case F_ELF:
 423         eh = elfhdr;
 424         eh.e.e_entry = htole32(hdr->entry);
 425         eh.p[0].p_vaddr = eh.p[0].p_paddr = htole32(hdr->org);
 426         eh.p[0].p_filesz = eh.p[0].p_memsz = htole32(hdr->text);
 427         eh.p[1].p_offset = htole32(le32toh(eh.p[0].p_offset) +
 428             le32toh(eh.p[0].p_filesz));
 429         eh.p[1].p_vaddr = eh.p[1].p_paddr =
 430             htole32(align(le32toh(eh.p[0].p_paddr) + le32toh(eh.p[0].p_memsz),
 431             4096));
 432         eh.p[1].p_filesz = eh.p[1].p_memsz = htole32(hdr->data);
 433         eh.sh[2].sh_addr = eh.p[0].p_vaddr;
 434         eh.sh[2].sh_offset = eh.p[0].p_offset;
 435         eh.sh[2].sh_size = eh.p[0].p_filesz;
 436         eh.sh[3].sh_addr = eh.p[1].p_vaddr;
 437         eh.sh[3].sh_offset = eh.p[1].p_offset;
 438         eh.sh[3].sh_size = eh.p[1].p_filesz;
 439         writex(fd, &eh, sizeof(eh));
 440         hdr->size = sizeof(eh);
 441     }
 442 }
 443
 444 /*
 445  * Safe copy from input file to output file.
 446  */
 447 static void
 448 copy(int fdi, int fdo, size_t nbyte, off_t offset)
 449 {
 450     char buf[8192];
 451     size_t n;
 452
 453     while (nbyte) {
 454         if ((n = sizeof(buf)) > nbyte)
 455             n = nbyte;
 456         if (readx(fdi, buf, n, offset) != n)
 457             errx(2, "%s: Short read", fname);
 458         writex(fdo, buf, n);
 459         nbyte -= n;
 460         offset = -1;
 461     }
 462 }
 463
 464 /*
 465  * Safe read from input file.
 466  */
 467 static size_t
 468 readx(int fd, void *buf, size_t nbyte, off_t offset)
 469 {
 470     ssize_t n;
 471
 472     if (offset != -1 && lseek(fd, offset, SEEK_SET) != offset)
 473         err(2, "%s", fname);
 474     if ((n = read(fd, buf, nbyte)) == -1)
 475         err(2, "%s", fname);
 476     return n;
 477 }
 478
 479 /*
 480  * Safe write to output file.
 481  */
 482 static void
 483 writex(int fd, const void *buf, size_t nbyte)
 484 {
 485     ssize_t n;
 486
 487     if ((n = write(fd, buf, nbyte)) == -1)
 488         err(2, "%s", tname);
 489     if ((size_t)n != nbyte)
 490         errx(2, "%s: Short write", tname);
 491 }
 492
 493 /*
 494  * Safe seek in output file.
 495  */
 496 static void
 497 seekx(int fd, off_t offset)
 498 {
 499     if (lseek(fd, offset, SEEK_SET) != offset)
 500         err(2, "%s", tname);
 501 }
 502
 503 /*
 504  * Convert an option argument to a format code.
 505  */
 506 static unsigned int
 507 optfmt(const char *arg)
 508 {
 509     unsigned int i;
 510
 511     for (i = 0; i < F_CNT && strcmp(arg, fmtlist[i]); i++);
 512     if (i == F_CNT)
 513         errx(1, "%s: Unknown format", arg);
 514     return i;
 515 }
 516
 517 /*
 518  * Convert an option argument to an address.
 519  */
 520 static uint32_t
 521 optaddr(const char *arg)
 522 {
 523     char *s;
 524     unsigned long x;
 525
 526     errno = 0;
 527     x = strtoul(arg, &s, 0);
 528     if (errno || !*arg || *s || x > MAXU32)
 529         errx(1, "%s: Illegal address", arg);
 530     return x;
 531 }
 532
 533 /*
 534  * Convert an option argument to a page number.
 535  */
 536 static int
 537 optpage(const char *arg, int hi)
 538 {
 539     char *s;
 540     long x;
 541
 542     errno = 0;
 543     x = strtol(arg, &s, 0);
 544     if (errno || !*arg || *s || x < 0 || x > hi)
 545         errx(1, "%s: Illegal page number", arg);
 546     return x;
 547 }
 548
 549 /*
 550  * Display a warning.
 551  */
 552 static void
 553 Warn(const char *locus, const char *fmt, ...)
 554 {
 555     va_list ap;
 556     char *s;
 557
 558     if (!quiet) {
 559         asprintf(&s, "%s: Warning: %s", locus, fmt);
 560         va_start(ap, fmt);
 561         vwarnx(s, ap);
 562         va_end(ap);
 563         free(s);
 564     }
 565 }
 566
 567 /*
 568  * Display usage information.
 569  */
 570 static void
 571 usage(void)
 572 {
 573     fprintf(stderr, "%s\n%s\n",
 574     "usage: btxld [-qv] [-b file] [-E address] [-e address] [-f format]",
 575     "             [-l file] [-o filename] [-P page] [-W page] file");
 576     exit(1);
 577 }