elf2bb.c revision 1.7.2.5
1 /* $NetBSD: elf2bb.c,v 1.7.2.5 2004/12/18 09:31:01 skrll Exp $ */ 2 3 /*- 4 * Copyright (c) 1996 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Ignatios Souvatzis. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #if HAVE_NBTOOL_CONFIG_H 40 #include "nbtool_config.h" 41 #endif 42 43 #include <sys/types.h> 44 45 #include <err.h> 46 #include <fcntl.h> 47 #include <stdio.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <unistd.h> 51 52 #include <sys/mman.h> /* of the machine we're running on */ 53 #include <sys/endian.h> /* of the machine we're running on */ 54 55 #include <sys/exec_elf.h> /* TARGET */ 56 #ifndef R_68K_32 /* XXX host not m68k XXX */ 57 #define R_68K_32 1 58 #define R_68K_PC32 4 59 #define R_68K_PC16 5 60 #endif 61 62 #include "elf2bb.h" 63 #include "chksum.h" 64 65 void usage(void); 66 int intcmp(const void *, const void *); 67 int main(int argc, char *argv[]); 68 69 #ifdef DEBUG 70 #define dprintf(x) if (debug) printf x 71 #else 72 #define dprintf(x) 73 #endif 74 int debug; 75 76 #define BBSIZE 8192 77 78 char *progname; 79 int bbsize = BBSIZE; 80 u_int8_t *buffer; 81 u_int32_t *relbuf; 82 /* can't have more relocs than that*/ 83 84 int 85 intcmp(const void *i, const void *j) 86 { 87 int r; 88 89 r = (*(u_int32_t *)i) < (*(u_int32_t *)j); 90 91 return 2*r-1; 92 } 93 94 int 95 main(int argc, char *argv[]) 96 { 97 int ifd, ofd; 98 u_int mid, flags, magic; 99 caddr_t image; 100 Elf32_Ehdr *eh; 101 Elf32_Shdr *sh; 102 char *shstrtab; 103 Elf32_Sym *symtab; 104 char *strtab; 105 int eval(Elf32_Sym *, u_int32_t *); 106 u_int32_t *lptr; 107 int i, l, delta; 108 u_int8_t *rpo; 109 u_int32_t oldaddr, addrdiff; 110 u_int32_t tsz, dsz, bsz, trsz, drsz, entry, relver; 111 u_int32_t pcrelsz, r32sz; 112 int sumsize = 16; 113 int c; 114 u_int32_t *sect_offset; 115 int undefsyms; 116 uint32_t tmp32; 117 uint16_t tmp16; 118 119 progname = argv[0]; 120 121 /* insert getopt here, if needed */ 122 while ((c = getopt(argc, argv, "dFS")) != -1) 123 switch(c) { 124 case 'F': 125 sumsize = 2; 126 break; 127 case 'S': 128 /* Dynamically size second-stage boot */ 129 sumsize = 0; 130 break; 131 case 'd': 132 debug = 1; 133 break; 134 default: 135 usage(); 136 } 137 argv += optind; 138 argc -= optind; 139 140 if (argc < 2) 141 usage(); 142 143 ifd = open(argv[0], O_RDONLY, 0); 144 if (ifd < 0) 145 err(1, "Can't open %s", argv[0]); 146 147 image = mmap(0, 65536, PROT_READ, MAP_FILE|MAP_PRIVATE, ifd, 0); 148 if (image == 0) 149 err(1, "Can't mmap %s", argv[1]); 150 151 eh = (Elf32_Ehdr *)image; /* XXX endianness */ 152 153 dprintf(("%04x sections, offset %08x\n", htobe16(eh->e_shnum), htobe32(eh->e_shoff))); 154 if (htobe16(eh->e_type) != ET_REL) 155 errx(1, "%s isn't a relocatable file, type=%d", 156 argv[0], htobe16(eh->e_type)); 157 if (htobe16(eh->e_machine) != EM_68K) 158 errx(1, "%s isn't M68K, machine=%d", argv[0], 159 htobe16(eh->e_machine)); 160 161 /* Calculate sizes from section headers. */ 162 tsz = dsz = bsz = trsz = pcrelsz = r32sz = 0; 163 sh = (Elf32_Shdr *)(image + htobe32(eh->e_shoff)); 164 shstrtab = (char *)(image + htobe32(sh[htobe16(eh->e_shstrndx)].sh_offset)); 165 symtab = NULL; /*XXX*/ 166 strtab = NULL; /*XXX*/ 167 dprintf((" name type flags addr offset size align\n")); 168 for (i = 0; i < htobe16(eh->e_shnum); ++i) { 169 u_int32_t sh_size; 170 171 dprintf( ("%2d: %08x %-16s %08x %08x %08x %08x %08x %08x\n", i, 172 htobe32(sh[i].sh_name), shstrtab + htobe32(sh[i].sh_name), 173 htobe32(sh[i].sh_type), 174 htobe32(sh[i].sh_flags), htobe32(sh[i].sh_addr), 175 htobe32(sh[i].sh_offset), htobe32(sh[i].sh_size), 176 htobe32(sh[i].sh_addralign))); 177 sh_size = (htobe32(sh[i].sh_size) + htobe32(sh[i].sh_addralign) - 1) & 178 -htobe32(sh[i].sh_addralign); 179 /* If section allocates memory, add to text, data, or bss size. */ 180 if (htobe32(sh[i].sh_flags) & SHF_ALLOC) { 181 if (htobe32(sh[i].sh_type) == SHT_PROGBITS) { 182 if (htobe32(sh[i].sh_flags) & SHF_WRITE) 183 dsz += sh_size; 184 else 185 tsz += sh_size; 186 } else 187 bsz += sh_size; 188 /* If it's relocations, add to relocation count */ 189 } else if (htobe32(sh[i].sh_type) == SHT_RELA) { 190 trsz += htobe32(sh[i].sh_size); 191 } 192 /* Check for SHT_REL? */ 193 /* Get symbol table location. */ 194 else if (htobe32(sh[i].sh_type) == SHT_SYMTAB) { 195 symtab = (Elf32_Sym *)(image + htobe32(sh[i].sh_offset)); 196 } else if (strcmp(".strtab", shstrtab + htobe32(sh[i].sh_name)) == 0) { 197 strtab = image + htobe32(sh[i].sh_offset); 198 } 199 } 200 dprintf(("tsz = 0x%x, dsz = 0x%x, bsz = 0x%x, total 0x%x\n", 201 tsz, dsz, bsz, tsz + dsz + bsz)); 202 203 if (trsz == 0) 204 errx(1, "%s has no relocation records.", argv[0]); 205 206 dprintf(("%d relocs\n", trsz/12)); 207 208 if (sumsize == 0) { 209 bbsize = (tsz + dsz + bsz + 511) & ~511; 210 sumsize = bbsize / 512; 211 } 212 213 buffer = malloc(bbsize); 214 relbuf = (u_int32_t *)malloc(bbsize); 215 if (buffer == NULL || relbuf == NULL) 216 err(1, "Unable to allocate memory\n"); 217 218 /* 219 * We have one contiguous area allocated by the ROM to us. 220 */ 221 if (tsz+dsz+bsz > bbsize) 222 errx(1, "%s: resulting image too big %d+%d+%d=%d", argv[0], 223 tsz, dsz, bsz, tsz + dsz + bsz); 224 225 memset(buffer, 0, bbsize); 226 227 /* Allocate and load loadable sections */ 228 sect_offset = (u_int32_t *)malloc(htobe16(eh->e_shnum) * sizeof(u_int32_t)); 229 for (i = 0, l = 0; i < htobe16(eh->e_shnum); ++i) { 230 if (htobe32(sh[i].sh_flags) & SHF_ALLOC) { 231 dprintf(("vaddr 0x%04x size 0x%04x offset 0x%04x section %s\n", 232 l, htobe32(sh[i].sh_size), htobe32(sh[i].sh_offset), 233 shstrtab + htobe32(sh[i].sh_name))); 234 if (htobe32(sh[i].sh_type) == SHT_PROGBITS) 235 memcpy(buffer + l, image + htobe32(sh[i].sh_offset), 236 htobe32(sh[i].sh_size)); 237 sect_offset[i] = l; 238 l += (htobe32(sh[i].sh_size) + htobe32(sh[i].sh_addralign) - 1) & 239 -htobe32(sh[i].sh_addralign); 240 } 241 } 242 243 /* 244 * Hm. This tool REALLY should understand more than one 245 * relocator version. For now, check that the relocator at 246 * the image start does understand what we output. 247 */ 248 relver = htobe32(*(u_int32_t *)(buffer + 4)); 249 switch (relver) { 250 default: 251 errx(1, "%s: unrecognized relocator version %d", 252 argv[0], relver); 253 /*NOTREACHED*/ 254 255 case RELVER_RELATIVE_BYTES: 256 rpo = buffer + bbsize - 1; 257 delta = -1; 258 break; 259 260 case RELVER_RELATIVE_BYTES_FORWARD: 261 rpo = buffer + tsz + dsz; 262 delta = +1; 263 *(u_int16_t *)(buffer + 14) = htobe16(tsz + dsz); 264 break; 265 } 266 267 if (symtab == NULL) 268 errx(1, "No symbol table found"); 269 /* 270 * Link sections and generate relocation data 271 * Nasty: .text, .rodata, .data, .bss sections are not linked 272 * Symbol table values relative to start of sections. 273 * For each relocation entry: 274 * Symbol value needs to be calculated: value + section offset 275 * Image data adjusted to calculated value of symbol + addend 276 * Add relocation table entry for 32-bit relocatable values 277 * PC-relative entries will be absolute and don't need relocation 278 */ 279 undefsyms = 0; 280 for (i = 0; i < htobe16(eh->e_shnum); ++i) { 281 int n; 282 Elf32_Rela *ra; 283 u_int8_t *base; 284 285 if (htobe32(sh[i].sh_type) != SHT_RELA) 286 continue; 287 base = NULL; 288 if (strncmp(shstrtab + htobe32(sh[i].sh_name), ".rela", 5) != 0) 289 err(1, "bad relocation section name %s", shstrtab + 290 htobe32(sh[i].sh_name)); 291 for (n = 0; n < htobe16(eh->e_shnum); ++n) { 292 if (strcmp(shstrtab + htobe32(sh[i].sh_name) + 5, shstrtab + 293 htobe32(sh[n].sh_name)) != 0) 294 continue; 295 base = buffer + sect_offset[n]; 296 break; 297 } 298 if (base == NULL) 299 errx(1, "Can't find section for reloc %s", shstrtab + 300 htobe32(sh[i].sh_name)); 301 ra = (Elf32_Rela *)(image + htobe32(sh[i].sh_offset)); 302 for (n = 0; n < htobe32(sh[i].sh_size); n += sizeof(Elf32_Rela), ++ra) { 303 Elf32_Sym *s; 304 int value; 305 306 s = &symtab[ELF32_R_SYM(htobe32(ra->r_info))]; 307 if (s->st_shndx == ELF_SYM_UNDEFINED) { 308 fprintf(stderr, "Undefined symbol: %s\n", 309 strtab + s->st_name); 310 ++undefsyms; 311 } 312 value = htobe32(ra->r_addend) + eval(s, sect_offset); 313 dprintf(("reloc %04x info %04x (type %d sym %d) add 0x%x val %x\n", 314 htobe32(ra->r_offset), htobe32(ra->r_info), 315 ELF32_R_TYPE(htobe32(ra->r_info)), 316 ELF32_R_SYM(htobe32(ra->r_info)), 317 htobe32(ra->r_addend), value)); 318 switch (ELF32_R_TYPE(htobe32(ra->r_info))) { 319 case R_68K_32: 320 tmp32 = htobe32(value); 321 memcpy(base + htobe32(ra->r_offset), &tmp32, 322 sizeof(tmp32)); 323 relbuf[r32sz++] = (base - buffer) + htobe32(ra->r_offset); 324 break; 325 case R_68K_PC32: 326 ++pcrelsz; 327 tmp32 = htobe32(value - htobe32(ra->r_offset)); 328 memcpy(base + htobe32(ra->r_offset), &tmp32, 329 sizeof(tmp32)); 330 break; 331 case R_68K_PC16: 332 ++pcrelsz; 333 value -= htobe32(ra->r_offset); 334 if (value < -0x8000 || value > 0x7fff) 335 errx(1, "PC-relative offset out of range: %x\n", 336 value); 337 tmp16 = htobe16(value); 338 memcpy(base + htobe32(ra->r_offset), &tmp16, 339 sizeof(tmp16)); 340 break; 341 default: 342 errx(1, "Relocation type %d not supported", 343 ELF32_R_TYPE(htobe32(ra->r_info))); 344 } 345 } 346 } 347 dprintf(("%d PC-relative relocations, %d 32-bit relocations\n", 348 pcrelsz, r32sz)); 349 printf("%d absolute reloc%s found, ", r32sz, r32sz==1?"":"s"); 350 351 i = r32sz; 352 if (i > 1) 353 heapsort(relbuf, r32sz, 4, intcmp); 354 355 oldaddr = 0; 356 357 for (--i; i>=0; --i) { 358 dprintf(("0x%04x: ", relbuf[i])); 359 lptr = (u_int32_t *)&buffer[relbuf[i]]; 360 addrdiff = relbuf[i] - oldaddr; 361 dprintf(("(0x%04x, 0x%04x): ", *lptr, addrdiff)); 362 if (addrdiff > 255) { 363 *rpo = 0; 364 if (delta > 0) { 365 ++rpo; 366 *rpo++ = (relbuf[i] >> 8) & 0xff; 367 *rpo++ = relbuf[i] & 0xff; 368 dprintf(("%02x%02x%02x\n", 369 rpo[-3], rpo[-2], rpo[-1])); 370 } else { 371 *--rpo = relbuf[i] & 0xff; 372 *--rpo = (relbuf[i] >> 8) & 0xff; 373 --rpo; 374 dprintf(("%02x%02x%02x\n", 375 rpo[0], rpo[1], rpo[2])); 376 } 377 } else { 378 *rpo = addrdiff; 379 dprintf(("%02x\n", *rpo)); 380 rpo += delta; 381 } 382 383 oldaddr = relbuf[i]; 384 385 if (delta < 0 ? rpo <= buffer+tsz+dsz 386 : rpo >= buffer + bbsize) 387 errx(1, "Relocs don't fit."); 388 } 389 *rpo = 0; rpo += delta; 390 *rpo = 0; rpo += delta; 391 *rpo = 0; rpo += delta; 392 393 printf("using %d bytes, %d bytes remaining.\n", delta > 0 ? 394 rpo-buffer-tsz-dsz : buffer+bbsize-rpo, delta > 0 ? 395 buffer + bbsize - rpo : rpo - buffer - tsz - dsz); 396 /* 397 * RELOCs must fit into the bss area. 398 */ 399 if (delta < 0 ? rpo <= buffer+tsz+dsz 400 : rpo >= buffer + bbsize) 401 errx(1, "Relocs don't fit."); 402 403 if (undefsyms > 0) 404 errx(1, "Undefined symbols referenced"); 405 406 ((u_int32_t *)buffer)[1] = 0; 407 ((u_int32_t *)buffer)[1] = 408 htobe32((0xffffffff - chksum((u_int32_t *)buffer, sumsize * 512 / 4))); 409 410 ofd = open(argv[1], O_CREAT|O_WRONLY, 0644); 411 if (ofd < 0) 412 err(1, "Can't open %s", argv[1]); 413 414 if (write(ofd, buffer, bbsize) != bbsize) 415 err(1, "Writing output file"); 416 417 exit(0); 418 } 419 420 void 421 usage(void) 422 { 423 fprintf(stderr, "Usage: %s [-F] bootprog bootprog.bin\n", 424 progname); 425 exit(1); 426 /* NOTREACHED */ 427 } 428 429 int 430 eval(Elf32_Sym *s, u_int32_t *o) 431 { 432 int value; 433 434 value = htobe32(s->st_value); 435 if (htobe16(s->st_shndx) < 0xf000) 436 value += o[htobe16(s->st_shndx)]; 437 else 438 printf("eval: %x\n", htobe16(s->st_shndx)); 439 return value; 440 } 441
Indexes created Mon Oct 27 17:09:47 GMT 2025