sys/kern/link_elf_obj.c

   1 /*-
   2  * Copyright (c) 1998-2000 Doug Rabson
   3  * Copyright (c) 2004 Peter Wemm
   4  * 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  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 #include "opt_ddb.h"
  32
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/kernel.h>
  36 #include <sys/lock.h>
  37 #include <sys/malloc.h>
  38 #include <sys/mutex.h>
  39 #include <sys/mount.h>
  40 #include <sys/proc.h>
  41 #include <sys/namei.h>
  42 #include <sys/fcntl.h>
  43 #include <sys/vnode.h>
  44 #include <sys/linker.h>
  45
  46 #include <machine/elf.h>
  47
  48 #include <net/vnet.h>
  49
  50 #include <security/mac/mac_framework.h>
  51
  52 #include <vm/vm.h>
  53 #include <vm/vm_param.h>
  54 #include <vm/vm_object.h>
  55 #include <vm/vm_kern.h>
  56 #include <vm/vm_extern.h>
  57 #include <vm/pmap.h>
  58 #include <vm/vm_map.h>
  59
  60 #include <sys/link_elf.h>
  61
  62 #ifdef DDB_CTF
  63 #include <net/zlib.h>
  64 #endif
  65
  66 #include "linker_if.h"
  67
  68 typedef struct {
  69         void            *addr;
  70         Elf_Off         size;
  71         int             flags;
  72         int             sec;    /* Original section */
  73         char            *name;
  74 } Elf_progent;
  75
  76 typedef struct {
  77         Elf_Rel         *rel;
  78         int             nrel;
  79         int             sec;
  80 } Elf_relent;
  81
  82 typedef struct {
  83         Elf_Rela        *rela;
  84         int             nrela;
  85         int             sec;
  86 } Elf_relaent;
  87
  88
  89 typedef struct elf_file {
  90         struct linker_file lf;          /* Common fields */
  91
  92         int             preloaded;
  93         caddr_t         address;        /* Relocation address */
  94         vm_object_t     object;         /* VM object to hold file pages */
  95         Elf_Shdr        *e_shdr;
  96
  97         Elf_progent     *progtab;
  98         int             nprogtab;
  99
 100         Elf_relaent     *relatab;
 101         int             nrelatab;
 102
 103         Elf_relent      *reltab;
 104         int             nreltab;
 105
 106         Elf_Sym         *ddbsymtab;     /* The symbol table we are using */
 107         long            ddbsymcnt;      /* Number of symbols */
 108         caddr_t         ddbstrtab;      /* String table */
 109         long            ddbstrcnt;      /* number of bytes in string table */
 110
 111         caddr_t         shstrtab;       /* Section name string table */
 112         long            shstrcnt;       /* number of bytes in string table */
 113
 114         caddr_t         ctftab;         /* CTF table */
 115         long            ctfcnt;         /* number of bytes in CTF table */
 116         caddr_t         ctfoff;         /* CTF offset table */
 117         caddr_t         typoff;         /* Type offset table */
 118         long            typlen;         /* Number of type entries. */
 119
 120 } *elf_file_t;
 121
 122 #include <kern/kern_ctf.c>
 123
 124 static int      link_elf_link_preload(linker_class_t cls,
 125                     const char *, linker_file_t *);
 126 static int      link_elf_link_preload_finish(linker_file_t);
 127 static int      link_elf_load_file(linker_class_t, const char *, linker_file_t *);
 128 static int      link_elf_lookup_symbol(linker_file_t, const char *,
 129                     c_linker_sym_t *);
 130 static int      link_elf_symbol_values(linker_file_t, c_linker_sym_t,
 131                     linker_symval_t *);
 132 static int      link_elf_search_symbol(linker_file_t, caddr_t value,
 133                     c_linker_sym_t *sym, long *diffp);
 134
 135 static void     link_elf_unload_file(linker_file_t);
 136 static int      link_elf_lookup_set(linker_file_t, const char *,
 137                     void ***, void ***, int *);
 138 static int      link_elf_each_function_name(linker_file_t,
 139                     int (*)(const char *, void *), void *);
 140 static int      link_elf_each_function_nameval(linker_file_t,
 141                                 linker_function_nameval_callback_t,
 142                                 void *);
 143 static void     link_elf_reloc_local(linker_file_t);
 144 static long     link_elf_symtab_get(linker_file_t, const Elf_Sym **);
 145 static long     link_elf_strtab_get(linker_file_t, caddr_t *);
 146
 147 static Elf_Addr elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps);
 148
 149 static kobj_method_t link_elf_methods[] = {
 150         KOBJMETHOD(linker_lookup_symbol,        link_elf_lookup_symbol),
 151         KOBJMETHOD(linker_symbol_values,        link_elf_symbol_values),
 152         KOBJMETHOD(linker_search_symbol,        link_elf_search_symbol),
 153         KOBJMETHOD(linker_unload,               link_elf_unload_file),
 154         KOBJMETHOD(linker_load_file,            link_elf_load_file),
 155         KOBJMETHOD(linker_link_preload,         link_elf_link_preload),
 156         KOBJMETHOD(linker_link_preload_finish,  link_elf_link_preload_finish),
 157         KOBJMETHOD(linker_lookup_set,           link_elf_lookup_set),
 158         KOBJMETHOD(linker_each_function_name,   link_elf_each_function_name),
 159         KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval),
 160         KOBJMETHOD(linker_ctf_get,              link_elf_ctf_get),
 161         KOBJMETHOD(linker_symtab_get,           link_elf_symtab_get),
 162         KOBJMETHOD(linker_strtab_get,           link_elf_strtab_get),
 163         { 0, 0 }
 164 };
 165
 166 static struct linker_class link_elf_class = {
 167 #if ELF_TARG_CLASS == ELFCLASS32
 168         "elf32_obj",
 169 #else
 170         "elf64_obj",
 171 #endif
 172         link_elf_methods, sizeof(struct elf_file)
 173 };
 174
 175 static int      relocate_file(elf_file_t ef);
 176
 177 static void
 178 link_elf_error(const char *filename, const char *s)
 179 {
 180         if (filename == NULL)
 181                 printf("kldload: %s\n", s);
 182         else
 183                 printf("kldload: %s: %s\n", filename, s);
 184 }
 185
 186 static void
 187 link_elf_init(void *arg)
 188 {
 189
 190         linker_add_class(&link_elf_class);
 191 }
 192
 193 SYSINIT(link_elf_obj, SI_SUB_KLD, SI_ORDER_SECOND, link_elf_init, 0);
 194
 195 static int
 196 link_elf_link_preload(linker_class_t cls, const char *filename,
 197     linker_file_t *result)
 198 {
 199         Elf_Ehdr *hdr;
 200         Elf_Shdr *shdr;
 201         Elf_Sym *es;
 202         void *modptr, *baseptr, *sizeptr;
 203         char *type;
 204         elf_file_t ef;
 205         linker_file_t lf;
 206         Elf_Addr off;
 207         int error, i, j, pb, ra, rl, shstrindex, symstrindex, symtabindex;
 208
 209         /* Look to see if we have the file preloaded */
 210         modptr = preload_search_by_name(filename);
 211         if (modptr == NULL)
 212                 return ENOENT;
 213
 214         type = (char *)preload_search_info(modptr, MODINFO_TYPE);
 215         baseptr = preload_search_info(modptr, MODINFO_ADDR);
 216         sizeptr = preload_search_info(modptr, MODINFO_SIZE);
 217         hdr = (Elf_Ehdr *)preload_search_info(modptr, MODINFO_METADATA |
 218             MODINFOMD_ELFHDR);
 219         shdr = (Elf_Shdr *)preload_search_info(modptr, MODINFO_METADATA |
 220             MODINFOMD_SHDR);
 221         if (type == NULL || (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE)
 222             " obj module") != 0 &&
 223             strcmp(type, "elf obj module") != 0)) {
 224                 return (EFTYPE);
 225         }
 226         if (baseptr == NULL || sizeptr == NULL || hdr == NULL ||
 227             shdr == NULL)
 228                 return (EINVAL);
 229
 230         lf = linker_make_file(filename, &link_elf_class);
 231         if (lf == NULL)
 232                 return (ENOMEM);
 233
 234         ef = (elf_file_t)lf;
 235         ef->preloaded = 1;
 236         ef->address = *(caddr_t *)baseptr;
 237         lf->address = *(caddr_t *)baseptr;
 238         lf->size = *(size_t *)sizeptr;
 239
 240         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
 241             hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
 242             hdr->e_ident[EI_VERSION] != EV_CURRENT ||
 243             hdr->e_version != EV_CURRENT ||
 244             hdr->e_type != ET_REL ||
 245             hdr->e_machine != ELF_TARG_MACH) {
 246                 error = EFTYPE;
 247                 goto out;
 248         }
 249         ef->e_shdr = shdr;
 250
 251         /* Scan the section header for information and table sizing. */
 252         symtabindex = -1;
 253         symstrindex = -1;
 254         for (i = 0; i < hdr->e_shnum; i++) {
 255                 switch (shdr[i].sh_type) {
 256                 case SHT_PROGBITS:
 257                 case SHT_NOBITS:
 258 #ifdef __amd64__
 259                 case SHT_AMD64_UNWIND:
 260 #endif
 261                         ef->nprogtab++;
 262                         break;
 263                 case SHT_SYMTAB:
 264                         symtabindex = i;
 265                         symstrindex = shdr[i].sh_link;
 266                         break;
 267                 case SHT_REL:
 268                         ef->nreltab++;
 269                         break;
 270                 case SHT_RELA:
 271                         ef->nrelatab++;
 272                         break;
 273                 }
 274         }
 275
 276         shstrindex = hdr->e_shstrndx;
 277         if (ef->nprogtab == 0 || symstrindex < 0 ||
 278             symstrindex >= hdr->e_shnum ||
 279             shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 ||
 280             shstrindex >= hdr->e_shnum ||
 281             shdr[shstrindex].sh_type != SHT_STRTAB) {
 282                 printf("%s: bad/missing section headers\n", filename);
 283                 error = ENOEXEC;
 284                 goto out;
 285         }
 286
 287         /* Allocate space for tracking the load chunks */
 288         if (ef->nprogtab != 0)
 289                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
 290                     M_LINKER, M_WAITOK | M_ZERO);
 291         if (ef->nreltab != 0)
 292                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
 293                     M_LINKER, M_WAITOK | M_ZERO);
 294         if (ef->nrelatab != 0)
 295                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
 296                     M_LINKER, M_WAITOK | M_ZERO);
 297         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
 298             (ef->nreltab != 0 && ef->reltab == NULL) ||
 299             (ef->nrelatab != 0 && ef->relatab == NULL)) {
 300                 error = ENOMEM;
 301                 goto out;
 302         }
 303
 304         /* XXX, relocate the sh_addr fields saved by the loader. */
 305         off = 0;
 306         for (i = 0; i < hdr->e_shnum; i++) {
 307                 if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off))
 308                         off = shdr[i].sh_addr;
 309         }
 310         for (i = 0; i < hdr->e_shnum; i++) {
 311                 if (shdr[i].sh_addr != 0)
 312                         shdr[i].sh_addr = shdr[i].sh_addr - off +
 313                             (Elf_Addr)ef->address;
 314         }
 315
 316         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
 317         ef->ddbsymtab = (Elf_Sym *)shdr[symtabindex].sh_addr;
 318         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 319         ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr;
 320         ef->shstrcnt = shdr[shstrindex].sh_size;
 321         ef->shstrtab = (char *)shdr[shstrindex].sh_addr;
 322
 323         /* Now fill out progtab and the relocation tables. */
 324         pb = 0;
 325         rl = 0;
 326         ra = 0;
 327         for (i = 0; i < hdr->e_shnum; i++) {
 328                 switch (shdr[i].sh_type) {
 329                 case SHT_PROGBITS:
 330                 case SHT_NOBITS:
 331 #ifdef __amd64__
 332                 case SHT_AMD64_UNWIND:
 333 #endif
 334                         ef->progtab[pb].addr = (void *)shdr[i].sh_addr;
 335                         if (shdr[i].sh_type == SHT_PROGBITS)
 336                                 ef->progtab[pb].name = "<<PROGBITS>>";
 337 #ifdef __amd64__
 338                         else if (shdr[i].sh_type == SHT_AMD64_UNWIND)
 339                                 ef->progtab[pb].name = "<<UNWIND>>";
 340 #endif
 341                         else
 342                                 ef->progtab[pb].name = "<<NOBITS>>";
 343                         ef->progtab[pb].size = shdr[i].sh_size;
 344                         ef->progtab[pb].sec = i;
 345                         if (ef->shstrtab && shdr[i].sh_name != 0)
 346                                 ef->progtab[pb].name =
 347                                     ef->shstrtab + shdr[i].sh_name;
 348                         if (ef->progtab[pb].name != NULL &&
 349                             !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) {
 350                                 void *dpcpu;
 351
 352                                 dpcpu = dpcpu_alloc(shdr[i].sh_size);
 353                                 if (dpcpu == NULL) {
 354                                         error = ENOSPC;
 355                                         goto out;
 356                                 }
 357                                 memcpy(dpcpu, ef->progtab[pb].addr,
 358                                     ef->progtab[pb].size);
 359                                 dpcpu_copy(dpcpu, shdr[i].sh_size);
 360                                 ef->progtab[pb].addr = dpcpu;
 361 #ifdef VIMAGE
 362                         } else if (ef->progtab[pb].name != NULL &&
 363                             !strcmp(ef->progtab[pb].name, VNET_SETNAME)) {
 364                                 void *vnet_data;
 365
 366                                 vnet_data = vnet_data_alloc(shdr[i].sh_size);
 367                                 if (vnet_data == NULL) {
 368                                         error = ENOSPC;
 369                                         goto out;
 370                                 }
 371                                 memcpy(vnet_data, ef->progtab[pb].addr,
 372                                     ef->progtab[pb].size);
 373                                 vnet_data_copy(vnet_data, shdr[i].sh_size);
 374                                 ef->progtab[pb].addr = vnet_data;
 375 #endif
 376                         }
 377
 378                         /* Update all symbol values with the offset. */
 379                         for (j = 0; j < ef->ddbsymcnt; j++) {
 380                                 es = &ef->ddbsymtab[j];
 381                                 if (es->st_shndx != i)
 382                                         continue;
 383                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 384                         }
 385                         pb++;
 386                         break;
 387                 case SHT_REL:
 388                         ef->reltab[rl].rel = (Elf_Rel *)shdr[i].sh_addr;
 389                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 390                         ef->reltab[rl].sec = shdr[i].sh_info;
 391                         rl++;
 392                         break;
 393                 case SHT_RELA:
 394                         ef->relatab[ra].rela = (Elf_Rela *)shdr[i].sh_addr;
 395                         ef->relatab[ra].nrela =
 396                             shdr[i].sh_size / sizeof(Elf_Rela);
 397                         ef->relatab[ra].sec = shdr[i].sh_info;
 398                         ra++;
 399                         break;
 400                 }
 401         }
 402         if (pb != ef->nprogtab)
 403                 panic("lost progbits");
 404         if (rl != ef->nreltab)
 405                 panic("lost reltab");
 406         if (ra != ef->nrelatab)
 407                 panic("lost relatab");
 408
 409         /* Local intra-module relocations */
 410         link_elf_reloc_local(lf);
 411
 412         *result = lf;
 413         return (0);
 414
 415 out:
 416         /* preload not done this way */
 417         linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 418         return (error);
 419 }
 420
 421 static int
 422 link_elf_link_preload_finish(linker_file_t lf)
 423 {
 424         elf_file_t ef;
 425         int error;
 426
 427         ef = (elf_file_t)lf;
 428         error = relocate_file(ef);
 429         if (error)
 430                 return error;
 431
 432         /* Notify MD code that a module is being loaded. */
 433         error = elf_cpu_load_file(lf);
 434         if (error)
 435                 return (error);
 436
 437         return (0);
 438 }
 439
 440 static int
 441 link_elf_load_file(linker_class_t cls, const char *filename,
 442     linker_file_t *result)
 443 {
 444         struct nameidata nd;
 445         struct thread *td = curthread;  /* XXX */
 446         Elf_Ehdr *hdr;
 447         Elf_Shdr *shdr;
 448         Elf_Sym *es;
 449         int nbytes, i, j;
 450         vm_offset_t mapbase;
 451         size_t mapsize;
 452         int error = 0;
 453         ssize_t resid;
 454         int flags;
 455         elf_file_t ef;
 456         linker_file_t lf;
 457         int symtabindex;
 458         int symstrindex;
 459         int shstrindex;
 460         int nsym;
 461         int pb, rl, ra;
 462         int alignmask;
 463         int vfslocked;
 464
 465         shdr = NULL;
 466         lf = NULL;
 467         mapsize = 0;
 468         hdr = NULL;
 469
 470         NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, filename, td);
 471         flags = FREAD;
 472         error = vn_open(&nd, &flags, 0, NULL);
 473         if (error)
 474                 return error;
 475         vfslocked = NDHASGIANT(&nd);
 476         NDFREE(&nd, NDF_ONLY_PNBUF);
 477         if (nd.ni_vp->v_type != VREG) {
 478                 error = ENOEXEC;
 479                 goto out;
 480         }
 481 #ifdef MAC
 482         error = mac_kld_check_load(td->td_ucred, nd.ni_vp);
 483         if (error) {
 484                 goto out;
 485         }
 486 #endif
 487
 488         /* Read the elf header from the file. */
 489         hdr = malloc(sizeof(*hdr), M_LINKER, M_WAITOK);
 490         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)hdr, sizeof(*hdr), 0,
 491             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 492             &resid, td);
 493         if (error)
 494                 goto out;
 495         if (resid != 0){
 496                 error = ENOEXEC;
 497                 goto out;
 498         }
 499
 500         if (!IS_ELF(*hdr)) {
 501                 error = ENOEXEC;
 502                 goto out;
 503         }
 504
 505         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
 506             || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
 507                 link_elf_error(filename, "Unsupported file layout");
 508                 error = ENOEXEC;
 509                 goto out;
 510         }
 511         if (hdr->e_ident[EI_VERSION] != EV_CURRENT
 512             || hdr->e_version != EV_CURRENT) {
 513                 link_elf_error(filename, "Unsupported file version");
 514                 error = ENOEXEC;
 515                 goto out;
 516         }
 517         if (hdr->e_type != ET_REL) {
 518                 error = ENOSYS;
 519                 goto out;
 520         }
 521         if (hdr->e_machine != ELF_TARG_MACH) {
 522                 link_elf_error(filename, "Unsupported machine");
 523                 error = ENOEXEC;
 524                 goto out;
 525         }
 526
 527         lf = linker_make_file(filename, &link_elf_class);
 528         if (!lf) {
 529                 error = ENOMEM;
 530                 goto out;
 531         }
 532         ef = (elf_file_t) lf;
 533         ef->nprogtab = 0;
 534         ef->e_shdr = 0;
 535         ef->nreltab = 0;
 536         ef->nrelatab = 0;
 537
 538         /* Allocate and read in the section header */
 539         nbytes = hdr->e_shnum * hdr->e_shentsize;
 540         if (nbytes == 0 || hdr->e_shoff == 0 ||
 541             hdr->e_shentsize != sizeof(Elf_Shdr)) {
 542                 error = ENOEXEC;
 543                 goto out;
 544         }
 545         shdr = malloc(nbytes, M_LINKER, M_WAITOK);
 546         ef->e_shdr = shdr;
 547         error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shdr, nbytes, hdr->e_shoff,
 548             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td);
 549         if (error)
 550                 goto out;
 551         if (resid) {
 552                 error = ENOEXEC;
 553                 goto out;
 554         }
 555
 556         /* Scan the section header for information and table sizing. */
 557         nsym = 0;
 558         symtabindex = -1;
 559         symstrindex = -1;
 560         for (i = 0; i < hdr->e_shnum; i++) {
 561                 if (shdr[i].sh_size == 0)
 562                         continue;
 563                 switch (shdr[i].sh_type) {
 564                 case SHT_PROGBITS:
 565                 case SHT_NOBITS:
 566 #ifdef __amd64__
 567                 case SHT_AMD64_UNWIND:
 568 #endif
 569                         ef->nprogtab++;
 570                         break;
 571                 case SHT_SYMTAB:
 572                         nsym++;
 573                         symtabindex = i;
 574                         symstrindex = shdr[i].sh_link;
 575                         break;
 576                 case SHT_REL:
 577                         ef->nreltab++;
 578                         break;
 579                 case SHT_RELA:
 580                         ef->nrelatab++;
 581                         break;
 582                 case SHT_STRTAB:
 583                         break;
 584                 }
 585         }
 586         if (ef->nprogtab == 0) {
 587                 link_elf_error(filename, "file has no contents");
 588                 error = ENOEXEC;
 589                 goto out;
 590         }
 591         if (nsym != 1) {
 592                 /* Only allow one symbol table for now */
 593                 link_elf_error(filename, "file has no valid symbol table");
 594                 error = ENOEXEC;
 595                 goto out;
 596         }
 597         if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
 598             shdr[symstrindex].sh_type != SHT_STRTAB) {
 599                 link_elf_error(filename, "file has invalid symbol strings");
 600                 error = ENOEXEC;
 601                 goto out;
 602         }
 603
 604         /* Allocate space for tracking the load chunks */
 605         if (ef->nprogtab != 0)
 606                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
 607                     M_LINKER, M_WAITOK | M_ZERO);
 608         if (ef->nreltab != 0)
 609                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
 610                     M_LINKER, M_WAITOK | M_ZERO);
 611         if (ef->nrelatab != 0)
 612                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
 613                     M_LINKER, M_WAITOK | M_ZERO);
 614
 615         if (symtabindex == -1)
 616                 panic("lost symbol table index");
 617         /* Allocate space for and load the symbol table */
 618         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
 619         ef->ddbsymtab = malloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK);
 620         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ef->ddbsymtab,
 621             shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
 622             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 623             &resid, td);
 624         if (error)
 625                 goto out;
 626         if (resid != 0){
 627                 error = EINVAL;
 628                 goto out;
 629         }
 630
 631         if (symstrindex == -1)
 632                 panic("lost symbol string index");
 633         /* Allocate space for and load the symbol strings */
 634         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 635         ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
 636         error = vn_rdwr(UIO_READ, nd.ni_vp, ef->ddbstrtab,
 637             shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
 638             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 639             &resid, td);
 640         if (error)
 641                 goto out;
 642         if (resid != 0){
 643                 error = EINVAL;
 644                 goto out;
 645         }
 646
 647         /* Do we have a string table for the section names?  */
 648         shstrindex = -1;
 649         if (hdr->e_shstrndx != 0 &&
 650             shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
 651                 shstrindex = hdr->e_shstrndx;
 652                 ef->shstrcnt = shdr[shstrindex].sh_size;
 653                 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER,
 654                     M_WAITOK);
 655                 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->shstrtab,
 656                     shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
 657                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 658                     &resid, td);
 659                 if (error)
 660                         goto out;
 661                 if (resid != 0){
 662                         error = EINVAL;
 663                         goto out;
 664                 }
 665         }
 666
 667         /* Size up code/data(progbits) and bss(nobits). */
 668         alignmask = 0;
 669         for (i = 0; i < hdr->e_shnum; i++) {
 670                 if (shdr[i].sh_size == 0)
 671                         continue;
 672                 switch (shdr[i].sh_type) {
 673                 case SHT_PROGBITS:
 674                 case SHT_NOBITS:
 675 #ifdef __amd64__
 676                 case SHT_AMD64_UNWIND:
 677 #endif
 678                         alignmask = shdr[i].sh_addralign - 1;
 679                         mapsize += alignmask;
 680                         mapsize &= ~alignmask;
 681                         mapsize += shdr[i].sh_size;
 682                         break;
 683                 }
 684         }
 685
 686         /*
 687          * We know how much space we need for the text/data/bss/etc.
 688          * This stuff needs to be in a single chunk so that profiling etc
 689          * can get the bounds and gdb can associate offsets with modules
 690          */
 691         ef->object = vm_object_allocate(OBJT_DEFAULT,
 692             round_page(mapsize) >> PAGE_SHIFT);
 693         if (ef->object == NULL) {
 694                 error = ENOMEM;
 695                 goto out;
 696         }
 697         ef->address = (caddr_t) vm_map_min(kernel_map);
 698
 699         /*
 700          * In order to satisfy amd64's architectural requirements on the
 701          * location of code and data in the kernel's address space, request a
 702          * mapping that is above the kernel.
 703          */
 704         mapbase = KERNBASE;
 705         error = vm_map_find(kernel_map, ef->object, 0, &mapbase,
 706             round_page(mapsize), TRUE, VM_PROT_ALL, VM_PROT_ALL, FALSE);
 707         if (error) {
 708                 vm_object_deallocate(ef->object);
 709                 ef->object = 0;
 710                 goto out;
 711         }
 712
 713         /* Wire the pages */
 714         error = vm_map_wire(kernel_map, mapbase,
 715             mapbase + round_page(mapsize),
 716             VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES);
 717         if (error != KERN_SUCCESS) {
 718                 error = ENOMEM;
 719                 goto out;
 720         }
 721
 722         /* Inform the kld system about the situation */
 723         lf->address = ef->address = (caddr_t)mapbase;
 724         lf->size = mapsize;
 725
 726         /*
 727          * Now load code/data(progbits), zero bss(nobits), allocate space for
 728          * and load relocs
 729          */
 730         pb = 0;
 731         rl = 0;
 732         ra = 0;
 733         alignmask = 0;
 734         for (i = 0; i < hdr->e_shnum; i++) {
 735                 if (shdr[i].sh_size == 0)
 736                         continue;
 737                 switch (shdr[i].sh_type) {
 738                 case SHT_PROGBITS:
 739                 case SHT_NOBITS:
 740 #ifdef __amd64__
 741                 case SHT_AMD64_UNWIND:
 742 #endif
 743                         alignmask = shdr[i].sh_addralign - 1;
 744                         mapbase += alignmask;
 745                         mapbase &= ~alignmask;
 746                         if (ef->shstrtab && shdr[i].sh_name != 0)
 747                                 ef->progtab[pb].name =
 748                                     ef->shstrtab + shdr[i].sh_name;
 749                         else if (shdr[i].sh_type == SHT_PROGBITS)
 750                                 ef->progtab[pb].name = "<<PROGBITS>>";
 751 #ifdef __amd64__
 752                         else if (shdr[i].sh_type == SHT_AMD64_UNWIND)
 753                                 ef->progtab[pb].name = "<<UNWIND>>";
 754 #endif
 755                         else
 756                                 ef->progtab[pb].name = "<<NOBITS>>";
 757                         if (ef->progtab[pb].name != NULL &&
 758                             !strcmp(ef->progtab[pb].name, DPCPU_SETNAME))
 759                                 ef->progtab[pb].addr =
 760                                     dpcpu_alloc(shdr[i].sh_size);
 761 #ifdef VIMAGE
 762                         else if (ef->progtab[pb].name != NULL &&
 763                             !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 764                                 ef->progtab[pb].addr =
 765                                     vnet_data_alloc(shdr[i].sh_size);
 766 #endif
 767                         else
 768                                 ef->progtab[pb].addr =
 769                                     (void *)(uintptr_t)mapbase;
 770                         if (ef->progtab[pb].addr == NULL) {
 771                                 error = ENOSPC;
 772                                 goto out;
 773                         }
 774                         ef->progtab[pb].size = shdr[i].sh_size;
 775                         ef->progtab[pb].sec = i;
 776                         if (shdr[i].sh_type == SHT_PROGBITS
 777 #ifdef __amd64__
 778                             || shdr[i].sh_type == SHT_AMD64_UNWIND
 779 #endif
 780                             ) {
 781                                 error = vn_rdwr(UIO_READ, nd.ni_vp,
 782                                     ef->progtab[pb].addr,
 783                                     shdr[i].sh_size, shdr[i].sh_offset,
 784                                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
 785                                     NOCRED, &resid, td);
 786                                 if (error)
 787                                         goto out;
 788                                 if (resid != 0){
 789                                         error = EINVAL;
 790                                         goto out;
 791                                 }
 792                                 /* Initialize the per-cpu or vnet area. */
 793                                 if (ef->progtab[pb].addr != (void *)mapbase &&
 794                                     !strcmp(ef->progtab[pb].name, DPCPU_SETNAME))
 795                                         dpcpu_copy(ef->progtab[pb].addr,
 796                                             shdr[i].sh_size);
 797 #ifdef VIMAGE
 798                                 else if (ef->progtab[pb].addr !=
 799                                     (void *)mapbase &&
 800                                     !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 801                                         vnet_data_copy(ef->progtab[pb].addr,
 802                                             shdr[i].sh_size);
 803 #endif
 804                         } else
 805                                 bzero(ef->progtab[pb].addr, shdr[i].sh_size);
 806
 807                         /* Update all symbol values with the offset. */
 808                         for (j = 0; j < ef->ddbsymcnt; j++) {
 809                                 es = &ef->ddbsymtab[j];
 810                                 if (es->st_shndx != i)
 811                                         continue;
 812                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 813                         }
 814                         mapbase += shdr[i].sh_size;
 815                         pb++;
 816                         break;
 817                 case SHT_REL:
 818                         ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER,
 819                             M_WAITOK);
 820                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 821                         ef->reltab[rl].sec = shdr[i].sh_info;
 822                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 823                             (void *)ef->reltab[rl].rel,
 824                             shdr[i].sh_size, shdr[i].sh_offset,
 825                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 826                             &resid, td);
 827                         if (error)
 828                                 goto out;
 829                         if (resid != 0){
 830                                 error = EINVAL;
 831                                 goto out;
 832                         }
 833                         rl++;
 834                         break;
 835                 case SHT_RELA:
 836                         ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER,
 837                             M_WAITOK);
 838                         ef->relatab[ra].nrela =
 839                             shdr[i].sh_size / sizeof(Elf_Rela);
 840                         ef->relatab[ra].sec = shdr[i].sh_info;
 841                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 842                             (void *)ef->relatab[ra].rela,
 843                             shdr[i].sh_size, shdr[i].sh_offset,
 844                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 845                             &resid, td);
 846                         if (error)
 847                                 goto out;
 848                         if (resid != 0){
 849                                 error = EINVAL;
 850                                 goto out;
 851                         }
 852                         ra++;
 853                         break;
 854                 }
 855         }
 856         if (pb != ef->nprogtab)
 857                 panic("lost progbits");
 858         if (rl != ef->nreltab)
 859                 panic("lost reltab");
 860         if (ra != ef->nrelatab)
 861                 panic("lost relatab");
 862         if (mapbase != (vm_offset_t)ef->address + mapsize)
 863                 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
 864                     (u_long)mapbase, ef->address, (u_long)mapsize,
 865                     (u_long)(vm_offset_t)ef->address + mapsize);
 866
 867         /* Local intra-module relocations */
 868         link_elf_reloc_local(lf);
 869
 870         /* Pull in dependencies */
 871         VOP_UNLOCK(nd.ni_vp, 0);
 872         error = linker_load_dependencies(lf);
 873         vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
 874         if (error)
 875                 goto out;
 876
 877         /* External relocations */
 878         error = relocate_file(ef);
 879         if (error)
 880                 goto out;
 881
 882         /* Notify MD code that a module is being loaded. */
 883         error = elf_cpu_load_file(lf);
 884         if (error)
 885                 goto out;
 886
 887         *result = lf;
 888
 889 out:
 890         VOP_UNLOCK(nd.ni_vp, 0);
 891         vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
 892         VFS_UNLOCK_GIANT(vfslocked);
 893         if (error && lf)
 894                 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 895         if (hdr)
 896                 free(hdr, M_LINKER);
 897
 898         return error;
 899 }
 900
 901 static void
 902 link_elf_unload_file(linker_file_t file)
 903 {
 904         elf_file_t ef = (elf_file_t) file;
 905         int i;
 906
 907         /* Notify MD code that a module is being unloaded. */
 908         elf_cpu_unload_file(file);
 909
 910         if (ef->progtab) {
 911                 for (i = 0; i < ef->nprogtab; i++) {
 912                         if (ef->progtab[i].size == 0)
 913                                 continue;
 914                         if (ef->progtab[i].name == NULL)
 915                                 continue;
 916                         if (!strcmp(ef->progtab[i].name, DPCPU_SETNAME))
 917                                 dpcpu_free(ef->progtab[i].addr,
 918                                     ef->progtab[i].size);
 919 #ifdef VIMAGE
 920                         else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
 921                                 vnet_data_free(ef->progtab[i].addr,
 922                                     ef->progtab[i].size);
 923 #endif
 924                 }
 925         }
 926         if (ef->preloaded) {
 927                 if (ef->reltab)
 928                         free(ef->reltab, M_LINKER);
 929                 if (ef->relatab)
 930                         free(ef->relatab, M_LINKER);
 931                 if (ef->progtab)
 932                         free(ef->progtab, M_LINKER);
 933                 if (ef->ctftab)
 934                         free(ef->ctftab, M_LINKER);
 935                 if (ef->ctfoff)
 936                         free(ef->ctfoff, M_LINKER);
 937                 if (ef->typoff)
 938                         free(ef->typoff, M_LINKER);
 939                 if (file->filename != NULL)
 940                         preload_delete_name(file->filename);
 941                 /* XXX reclaim module memory? */
 942                 return;
 943         }
 944
 945         for (i = 0; i < ef->nreltab; i++)
 946                 if (ef->reltab[i].rel)
 947                         free(ef->reltab[i].rel, M_LINKER);
 948         for (i = 0; i < ef->nrelatab; i++)
 949                 if (ef->relatab[i].rela)
 950                         free(ef->relatab[i].rela, M_LINKER);
 951         if (ef->reltab)
 952                 free(ef->reltab, M_LINKER);
 953         if (ef->relatab)
 954                 free(ef->relatab, M_LINKER);
 955         if (ef->progtab)
 956                 free(ef->progtab, M_LINKER);
 957
 958         if (ef->object) {
 959                 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
 960                     (vm_offset_t) ef->address +
 961                     (ef->object->size << PAGE_SHIFT));
 962         }
 963         if (ef->e_shdr)
 964                 free(ef->e_shdr, M_LINKER);
 965         if (ef->ddbsymtab)
 966                 free(ef->ddbsymtab, M_LINKER);
 967         if (ef->ddbstrtab)
 968                 free(ef->ddbstrtab, M_LINKER);
 969         if (ef->shstrtab)
 970                 free(ef->shstrtab, M_LINKER);
 971         if (ef->ctftab)
 972                 free(ef->ctftab, M_LINKER);
 973         if (ef->ctfoff)
 974                 free(ef->ctfoff, M_LINKER);
 975         if (ef->typoff)
 976                 free(ef->typoff, M_LINKER);
 977 }
 978
 979 static const char *
 980 symbol_name(elf_file_t ef, Elf_Size r_info)
 981 {
 982         const Elf_Sym *ref;
 983
 984         if (ELF_R_SYM(r_info)) {
 985                 ref = ef->ddbsymtab + ELF_R_SYM(r_info);
 986                 return ef->ddbstrtab + ref->st_name;
 987         } else
 988                 return NULL;
 989 }
 990
 991 static Elf_Addr
 992 findbase(elf_file_t ef, int sec)
 993 {
 994         int i;
 995         Elf_Addr base = 0;
 996
 997         for (i = 0; i < ef->nprogtab; i++) {
 998                 if (sec == ef->progtab[i].sec) {
 999                         base = (Elf_Addr)ef->progtab[i].addr;
1000                         break;
1001                 }
1002         }
1003         return base;
1004 }
1005
1006 static int
1007 relocate_file(elf_file_t ef)
1008 {
1009         const Elf_Rel *rellim;
1010         const Elf_Rel *rel;
1011         const Elf_Rela *relalim;
1012         const Elf_Rela *rela;
1013         const char *symname;
1014         const Elf_Sym *sym;
1015         int i;
1016         Elf_Size symidx;
1017         Elf_Addr base;
1018
1019
1020         /* Perform relocations without addend if there are any: */
1021         for (i = 0; i < ef->nreltab; i++) {
1022                 rel = ef->reltab[i].rel;
1023                 if (rel == NULL)
1024                         panic("lost a reltab!");
1025                 rellim = rel + ef->reltab[i].nrel;
1026                 base = findbase(ef, ef->reltab[i].sec);
1027                 if (base == 0)
1028                         panic("lost base for reltab");
1029                 for ( ; rel < rellim; rel++) {
1030                         symidx = ELF_R_SYM(rel->r_info);
1031                         if (symidx >= ef->ddbsymcnt)
1032                                 continue;
1033                         sym = ef->ddbsymtab + symidx;
1034                         /* Local relocs are already done */
1035                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1036                                 continue;
1037                         if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL,
1038                             elf_obj_lookup)) {
1039                                 symname = symbol_name(ef, rel->r_info);
1040                                 printf("link_elf_obj: symbol %s undefined\n",
1041                                     symname);
1042                                 return ENOENT;
1043                         }
1044                 }
1045         }
1046
1047         /* Perform relocations with addend if there are any: */
1048         for (i = 0; i < ef->nrelatab; i++) {
1049                 rela = ef->relatab[i].rela;
1050                 if (rela == NULL)
1051                         panic("lost a relatab!");
1052                 relalim = rela + ef->relatab[i].nrela;
1053                 base = findbase(ef, ef->relatab[i].sec);
1054                 if (base == 0)
1055                         panic("lost base for relatab");
1056                 for ( ; rela < relalim; rela++) {
1057                         symidx = ELF_R_SYM(rela->r_info);
1058                         if (symidx >= ef->ddbsymcnt)
1059                                 continue;
1060                         sym = ef->ddbsymtab + symidx;
1061                         /* Local relocs are already done */
1062                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1063                                 continue;
1064                         if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA,
1065                             elf_obj_lookup)) {
1066                                 symname = symbol_name(ef, rela->r_info);
1067                                 printf("link_elf_obj: symbol %s undefined\n",
1068                                     symname);
1069                                 return ENOENT;
1070                         }
1071                 }
1072         }
1073
1074         return 0;
1075 }
1076
1077 static int
1078 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
1079 {
1080         elf_file_t ef = (elf_file_t) lf;
1081         const Elf_Sym *symp;
1082         const char *strp;
1083         int i;
1084
1085         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1086                 strp = ef->ddbstrtab + symp->st_name;
1087                 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
1088                         *sym = (c_linker_sym_t) symp;
1089                         return 0;
1090                 }
1091         }
1092         return ENOENT;
1093 }
1094
1095 static int
1096 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym,
1097     linker_symval_t *symval)
1098 {
1099         elf_file_t ef = (elf_file_t) lf;
1100         const Elf_Sym *es = (const Elf_Sym*) sym;
1101
1102         if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1103                 symval->name = ef->ddbstrtab + es->st_name;
1104                 symval->value = (caddr_t)es->st_value;
1105                 symval->size = es->st_size;
1106                 return 0;
1107         }
1108         return ENOENT;
1109 }
1110
1111 static int
1112 link_elf_search_symbol(linker_file_t lf, caddr_t value,
1113     c_linker_sym_t *sym, long *diffp)
1114 {
1115         elf_file_t ef = (elf_file_t) lf;
1116         u_long off = (uintptr_t) (void *) value;
1117         u_long diff = off;
1118         u_long st_value;
1119         const Elf_Sym *es;
1120         const Elf_Sym *best = 0;
1121         int i;
1122
1123         for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1124                 if (es->st_name == 0)
1125                         continue;
1126                 st_value = es->st_value;
1127                 if (off >= st_value) {
1128                         if (off - st_value < diff) {
1129                                 diff = off - st_value;
1130                                 best = es;
1131                                 if (diff == 0)
1132                                         break;
1133                         } else if (off - st_value == diff) {
1134                                 best = es;
1135                         }
1136                 }
1137         }
1138         if (best == 0)
1139                 *diffp = off;
1140         else
1141                 *diffp = diff;
1142         *sym = (c_linker_sym_t) best;
1143
1144         return 0;
1145 }
1146
1147 /*
1148  * Look up a linker set on an ELF system.
1149  */
1150 static int
1151 link_elf_lookup_set(linker_file_t lf, const char *name,
1152     void ***startp, void ***stopp, int *countp)
1153 {
1154         elf_file_t ef = (elf_file_t)lf;
1155         void **start, **stop;
1156         int i, count;
1157
1158         /* Relative to section number */
1159         for (i = 0; i < ef->nprogtab; i++) {
1160                 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
1161                     strcmp(ef->progtab[i].name + 4, name) == 0) {
1162                         start  = (void **)ef->progtab[i].addr;
1163                         stop = (void **)((char *)ef->progtab[i].addr +
1164                             ef->progtab[i].size);
1165                         count = stop - start;
1166                         if (startp)
1167                                 *startp = start;
1168                         if (stopp)
1169                                 *stopp = stop;
1170                         if (countp)
1171                                 *countp = count;
1172                         return (0);
1173                 }
1174         }
1175         return (ESRCH);
1176 }
1177
1178 static int
1179 link_elf_each_function_name(linker_file_t file,
1180     int (*callback)(const char *, void *), void *opaque)
1181 {
1182         elf_file_t ef = (elf_file_t)file;
1183         const Elf_Sym *symp;
1184         int i, error;
1185
1186         /* Exhaustive search */
1187         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1188                 if (symp->st_value != 0 &&
1189                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1190                         error = callback(ef->ddbstrtab + symp->st_name, opaque);
1191                         if (error)
1192                                 return (error);
1193                 }
1194         }
1195         return (0);
1196 }
1197
1198 static int
1199 link_elf_each_function_nameval(linker_file_t file,
1200     linker_function_nameval_callback_t callback, void *opaque)
1201 {
1202         linker_symval_t symval;
1203         elf_file_t ef = (elf_file_t)file;
1204         const Elf_Sym* symp;
1205         int i, error;
1206
1207         /* Exhaustive search */
1208         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1209                 if (symp->st_value != 0 &&
1210                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1211                         error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval);
1212                         if (error)
1213                                 return (error);
1214                         error = callback(file, i, &symval, opaque);
1215                         if (error)
1216                                 return (error);
1217                 }
1218         }
1219         return (0);
1220 }
1221
1222 /*
1223  * Symbol lookup function that can be used when the symbol index is known (ie
1224  * in relocations). It uses the symbol index instead of doing a fully fledged
1225  * hash table based lookup when such is valid. For example for local symbols.
1226  * This is not only more efficient, it's also more correct. It's not always
1227  * the case that the symbol can be found through the hash table.
1228  */
1229 static Elf_Addr
1230 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps)
1231 {
1232         elf_file_t ef = (elf_file_t)lf;
1233         const Elf_Sym *sym;
1234         const char *symbol;
1235         Elf_Addr ret;
1236
1237         /* Don't even try to lookup the symbol if the index is bogus. */
1238         if (symidx >= ef->ddbsymcnt)
1239                 return (0);
1240
1241         sym = ef->ddbsymtab + symidx;
1242
1243         /* Quick answer if there is a definition included. */
1244         if (sym->st_shndx != SHN_UNDEF)
1245                 return (sym->st_value);
1246
1247         /* If we get here, then it is undefined and needs a lookup. */
1248         switch (ELF_ST_BIND(sym->st_info)) {
1249         case STB_LOCAL:
1250                 /* Local, but undefined? huh? */
1251                 return (0);
1252
1253         case STB_GLOBAL:
1254                 /* Relative to Data or Function name */
1255                 symbol = ef->ddbstrtab + sym->st_name;
1256
1257                 /* Force a lookup failure if the symbol name is bogus. */
1258                 if (*symbol == 0)
1259                         return (0);
1260                 ret = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
1261                 return ret;
1262
1263         case STB_WEAK:
1264                 printf("link_elf_obj: Weak symbols not supported\n");
1265                 return (0);
1266
1267         default:
1268                 return (0);
1269         }
1270 }
1271
1272 static void
1273 link_elf_fix_link_set(elf_file_t ef)
1274 {
1275         static const char startn[] = "__start_";
1276         static const char stopn[] = "__stop_";
1277         Elf_Sym *sym;
1278         const char *sym_name, *linkset_name;
1279         Elf_Addr startp, stopp;
1280         Elf_Size symidx;
1281         int start, i;
1282
1283         startp = stopp = 0;
1284         for (symidx = 1 /* zero entry is special */;
1285                 symidx < ef->ddbsymcnt; symidx++) {
1286                 sym = ef->ddbsymtab + symidx;
1287                 if (sym->st_shndx != SHN_UNDEF)
1288                         continue;
1289
1290                 sym_name = ef->ddbstrtab + sym->st_name;
1291                 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
1292                         start = 1;
1293                         linkset_name = sym_name + sizeof(startn) - 1;
1294                 }
1295                 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
1296                         start = 0;
1297                         linkset_name = sym_name + sizeof(stopn) - 1;
1298                 }
1299                 else
1300                         continue;
1301
1302                 for (i = 0; i < ef->nprogtab; i++) {
1303                         if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
1304                                 startp = (Elf_Addr)ef->progtab[i].addr;
1305                                 stopp = (Elf_Addr)(startp + ef->progtab[i].size);
1306                                 break;
1307                         }
1308                 }
1309                 if (i == ef->nprogtab)
1310                         continue;
1311
1312                 sym->st_value = start ? startp : stopp;
1313                 sym->st_shndx = i;
1314         }
1315 }
1316
1317 static void
1318 link_elf_reloc_local(linker_file_t lf)
1319 {
1320         elf_file_t ef = (elf_file_t)lf;
1321         const Elf_Rel *rellim;
1322         const Elf_Rel *rel;
1323         const Elf_Rela *relalim;
1324         const Elf_Rela *rela;
1325         const Elf_Sym *sym;
1326         Elf_Addr base;
1327         int i;
1328         Elf_Size symidx;
1329
1330         link_elf_fix_link_set(ef);
1331
1332         /* Perform relocations without addend if there are any: */
1333         for (i = 0; i < ef->nreltab; i++) {
1334                 rel = ef->reltab[i].rel;
1335                 if (rel == NULL)
1336                         panic("lost a reltab!");
1337                 rellim = rel + ef->reltab[i].nrel;
1338                 base = findbase(ef, ef->reltab[i].sec);
1339                 if (base == 0)
1340                         panic("lost base for reltab");
1341                 for ( ; rel < rellim; rel++) {
1342                         symidx = ELF_R_SYM(rel->r_info);
1343                         if (symidx >= ef->ddbsymcnt)
1344                                 continue;
1345                         sym = ef->ddbsymtab + symidx;
1346                         /* Only do local relocs */
1347                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1348                                 continue;
1349                         elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
1350                             elf_obj_lookup);
1351                 }
1352         }
1353
1354         /* Perform relocations with addend if there are any: */
1355         for (i = 0; i < ef->nrelatab; i++) {
1356                 rela = ef->relatab[i].rela;
1357                 if (rela == NULL)
1358                         panic("lost a relatab!");
1359                 relalim = rela + ef->relatab[i].nrela;
1360                 base = findbase(ef, ef->relatab[i].sec);
1361                 if (base == 0)
1362                         panic("lost base for relatab");
1363                 for ( ; rela < relalim; rela++) {
1364                         symidx = ELF_R_SYM(rela->r_info);
1365                         if (symidx >= ef->ddbsymcnt)
1366                                 continue;
1367                         sym = ef->ddbsymtab + symidx;
1368                         /* Only do local relocs */
1369                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1370                                 continue;
1371                         elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
1372                             elf_obj_lookup);
1373                 }
1374         }
1375 }
1376
1377 static long
1378 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
1379 {
1380     elf_file_t ef = (elf_file_t)lf;
1381
1382     *symtab = ef->ddbsymtab;
1383
1384     if (*symtab == NULL)
1385         return (0);
1386
1387     return (ef->ddbsymcnt);
1388 }
1389
1390 static long
1391 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
1392 {
1393     elf_file_t ef = (elf_file_t)lf;
1394
1395     *strtab = ef->ddbstrtab;
1396
1397     if (*strtab == NULL)
1398         return (0);
1399
1400     return (ef->ddbstrcnt);
1401 }