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                         ef->nprogtab++;
 259                         break;
 260                 case SHT_SYMTAB:
 261                         symtabindex = i;
 262                         symstrindex = shdr[i].sh_link;
 263                         break;
 264                 case SHT_REL:
 265                         ef->nreltab++;
 266                         break;
 267                 case SHT_RELA:
 268                         ef->nrelatab++;
 269                         break;
 270                 }
 271         }
 272
 273         shstrindex = hdr->e_shstrndx;
 274         if (ef->nprogtab == 0 || symstrindex < 0 ||
 275             symstrindex >= hdr->e_shnum ||
 276             shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 ||
 277             shstrindex >= hdr->e_shnum ||
 278             shdr[shstrindex].sh_type != SHT_STRTAB) {
 279                 printf("%s: bad/missing section headers\n", filename);
 280                 error = ENOEXEC;
 281                 goto out;
 282         }
 283
 284         /* Allocate space for tracking the load chunks */
 285         if (ef->nprogtab != 0)
 286                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
 287                     M_LINKER, M_WAITOK | M_ZERO);
 288         if (ef->nreltab != 0)
 289                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
 290                     M_LINKER, M_WAITOK | M_ZERO);
 291         if (ef->nrelatab != 0)
 292                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
 293                     M_LINKER, M_WAITOK | M_ZERO);
 294         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
 295             (ef->nreltab != 0 && ef->reltab == NULL) ||
 296             (ef->nrelatab != 0 && ef->relatab == NULL)) {
 297                 error = ENOMEM;
 298                 goto out;
 299         }
 300
 301         /* XXX, relocate the sh_addr fields saved by the loader. */
 302         off = 0;
 303         for (i = 0; i < hdr->e_shnum; i++) {
 304                 if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off))
 305                         off = shdr[i].sh_addr;
 306         }
 307         for (i = 0; i < hdr->e_shnum; i++) {
 308                 if (shdr[i].sh_addr != 0)
 309                         shdr[i].sh_addr = shdr[i].sh_addr - off +
 310                             (Elf_Addr)ef->address;
 311         }
 312
 313         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
 314         ef->ddbsymtab = (Elf_Sym *)shdr[symtabindex].sh_addr;
 315         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 316         ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr;
 317         ef->shstrcnt = shdr[shstrindex].sh_size;
 318         ef->shstrtab = (char *)shdr[shstrindex].sh_addr;
 319
 320         /* Now fill out progtab and the relocation tables. */
 321         pb = 0;
 322         rl = 0;
 323         ra = 0;
 324         for (i = 0; i < hdr->e_shnum; i++) {
 325                 switch (shdr[i].sh_type) {
 326                 case SHT_PROGBITS:
 327                 case SHT_NOBITS:
 328                         ef->progtab[pb].addr = (void *)shdr[i].sh_addr;
 329                         if (shdr[i].sh_type == SHT_PROGBITS)
 330                                 ef->progtab[pb].name = "<<PROGBITS>>";
 331                         else
 332                                 ef->progtab[pb].name = "<<NOBITS>>";
 333                         ef->progtab[pb].size = shdr[i].sh_size;
 334                         ef->progtab[pb].sec = i;
 335                         if (ef->shstrtab && shdr[i].sh_name != 0)
 336                                 ef->progtab[pb].name =
 337                                     ef->shstrtab + shdr[i].sh_name;
 338                         if (ef->progtab[pb].name != NULL &&
 339                             !strcmp(ef->progtab[pb].name, "set_pcpu")) {
 340                                 void *dpcpu;
 341
 342                                 dpcpu = dpcpu_alloc(shdr[i].sh_size);
 343                                 if (dpcpu == NULL) {
 344                                         error = ENOSPC;
 345                                         goto out;
 346                                 }
 347                                 memcpy(dpcpu, ef->progtab[pb].addr,
 348                                     ef->progtab[pb].size);
 349                                 dpcpu_copy(dpcpu, shdr[i].sh_size);
 350                                 ef->progtab[pb].addr = dpcpu;
 351 #ifdef VIMAGE
 352                         } else if (ef->progtab[pb].name != NULL &&
 353                             !strcmp(ef->progtab[pb].name, VNET_SETNAME)) {
 354                                 void *vnet_data;
 355
 356                                 vnet_data = vnet_data_alloc(shdr[i].sh_size);
 357                                 if (vnet_data == NULL) {
 358                                         error = ENOSPC;
 359                                         goto out;
 360                                 }
 361                                 memcpy(vnet_data, ef->progtab[pb].addr,
 362                                     ef->progtab[pb].size);
 363                                 vnet_data_copy(vnet_data, shdr[i].sh_size);
 364                                 ef->progtab[pb].addr = vnet_data;
 365 #endif
 366                         }
 367
 368                         /* Update all symbol values with the offset. */
 369                         for (j = 0; j < ef->ddbsymcnt; j++) {
 370                                 es = &ef->ddbsymtab[j];
 371                                 if (es->st_shndx != i)
 372                                         continue;
 373                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 374                         }
 375                         pb++;
 376                         break;
 377                 case SHT_REL:
 378                         ef->reltab[rl].rel = (Elf_Rel *)shdr[i].sh_addr;
 379                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 380                         ef->reltab[rl].sec = shdr[i].sh_info;
 381                         rl++;
 382                         break;
 383                 case SHT_RELA:
 384                         ef->relatab[ra].rela = (Elf_Rela *)shdr[i].sh_addr;
 385                         ef->relatab[ra].nrela =
 386                             shdr[i].sh_size / sizeof(Elf_Rela);
 387                         ef->relatab[ra].sec = shdr[i].sh_info;
 388                         ra++;
 389                         break;
 390                 }
 391         }
 392         if (pb != ef->nprogtab)
 393                 panic("lost progbits");
 394         if (rl != ef->nreltab)
 395                 panic("lost reltab");
 396         if (ra != ef->nrelatab)
 397                 panic("lost relatab");
 398
 399         /* Local intra-module relocations */
 400         link_elf_reloc_local(lf);
 401
 402         *result = lf;
 403         return (0);
 404
 405 out:
 406         /* preload not done this way */
 407         linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 408         return (error);
 409 }
 410
 411 static int
 412 link_elf_link_preload_finish(linker_file_t lf)
 413 {
 414         elf_file_t ef;
 415         int error;
 416
 417         ef = (elf_file_t)lf;
 418         error = relocate_file(ef);
 419         if (error)
 420                 return error;
 421
 422         /* Notify MD code that a module is being loaded. */
 423         error = elf_cpu_load_file(lf);
 424         if (error)
 425                 return (error);
 426
 427         return (0);
 428 }
 429
 430 static int
 431 link_elf_load_file(linker_class_t cls, const char *filename,
 432     linker_file_t *result)
 433 {
 434         struct nameidata nd;
 435         struct thread *td = curthread;  /* XXX */
 436         Elf_Ehdr *hdr;
 437         Elf_Shdr *shdr;
 438         Elf_Sym *es;
 439         int nbytes, i, j;
 440         vm_offset_t mapbase;
 441         size_t mapsize;
 442         int error = 0;
 443         int resid, flags;
 444         elf_file_t ef;
 445         linker_file_t lf;
 446         int symtabindex;
 447         int symstrindex;
 448         int shstrindex;
 449         int nsym;
 450         int pb, rl, ra;
 451         int alignmask;
 452         int vfslocked;
 453
 454         shdr = NULL;
 455         lf = NULL;
 456         mapsize = 0;
 457         hdr = NULL;
 458
 459         NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, filename, td);
 460         flags = FREAD;
 461         error = vn_open(&nd, &flags, 0, NULL);
 462         if (error)
 463                 return error;
 464         vfslocked = NDHASGIANT(&nd);
 465         NDFREE(&nd, NDF_ONLY_PNBUF);
 466         if (nd.ni_vp->v_type != VREG) {
 467                 error = ENOEXEC;
 468                 goto out;
 469         }
 470 #ifdef MAC
 471         error = mac_kld_check_load(td->td_ucred, nd.ni_vp);
 472         if (error) {
 473                 goto out;
 474         }
 475 #endif
 476
 477         /* Read the elf header from the file. */
 478         hdr = malloc(sizeof(*hdr), M_LINKER, M_WAITOK);
 479         if (hdr == NULL) {
 480                 error = ENOMEM;
 481                 goto out;
 482         }
 483         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)hdr, sizeof(*hdr), 0,
 484             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 485             &resid, td);
 486         if (error)
 487                 goto out;
 488         if (resid != 0){
 489                 error = ENOEXEC;
 490                 goto out;
 491         }
 492
 493         if (!IS_ELF(*hdr)) {
 494                 error = ENOEXEC;
 495                 goto out;
 496         }
 497
 498         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
 499             || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
 500                 link_elf_error(filename, "Unsupported file layout");
 501                 error = ENOEXEC;
 502                 goto out;
 503         }
 504         if (hdr->e_ident[EI_VERSION] != EV_CURRENT
 505             || hdr->e_version != EV_CURRENT) {
 506                 link_elf_error(filename, "Unsupported file version");
 507                 error = ENOEXEC;
 508                 goto out;
 509         }
 510         if (hdr->e_type != ET_REL) {
 511                 error = ENOSYS;
 512                 goto out;
 513         }
 514         if (hdr->e_machine != ELF_TARG_MACH) {
 515                 link_elf_error(filename, "Unsupported machine");
 516                 error = ENOEXEC;
 517                 goto out;
 518         }
 519
 520         lf = linker_make_file(filename, &link_elf_class);
 521         if (!lf) {
 522                 error = ENOMEM;
 523                 goto out;
 524         }
 525         ef = (elf_file_t) lf;
 526         ef->nprogtab = 0;
 527         ef->e_shdr = 0;
 528         ef->nreltab = 0;
 529         ef->nrelatab = 0;
 530
 531         /* Allocate and read in the section header */
 532         nbytes = hdr->e_shnum * hdr->e_shentsize;
 533         if (nbytes == 0 || hdr->e_shoff == 0 ||
 534             hdr->e_shentsize != sizeof(Elf_Shdr)) {
 535                 error = ENOEXEC;
 536                 goto out;
 537         }
 538         shdr = malloc(nbytes, M_LINKER, M_WAITOK);
 539         if (shdr == NULL) {
 540                 error = ENOMEM;
 541                 goto out;
 542         }
 543         ef->e_shdr = shdr;
 544         error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shdr, nbytes, hdr->e_shoff,
 545             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td);
 546         if (error)
 547                 goto out;
 548         if (resid) {
 549                 error = ENOEXEC;
 550                 goto out;
 551         }
 552
 553         /* Scan the section header for information and table sizing. */
 554         nsym = 0;
 555         symtabindex = -1;
 556         symstrindex = -1;
 557         for (i = 0; i < hdr->e_shnum; i++) {
 558                 if (shdr[i].sh_size == 0)
 559                         continue;
 560                 switch (shdr[i].sh_type) {
 561                 case SHT_PROGBITS:
 562                 case SHT_NOBITS:
 563                         ef->nprogtab++;
 564                         break;
 565                 case SHT_SYMTAB:
 566                         nsym++;
 567                         symtabindex = i;
 568                         symstrindex = shdr[i].sh_link;
 569                         break;
 570                 case SHT_REL:
 571                         ef->nreltab++;
 572                         break;
 573                 case SHT_RELA:
 574                         ef->nrelatab++;
 575                         break;
 576                 case SHT_STRTAB:
 577                         break;
 578                 }
 579         }
 580         if (ef->nprogtab == 0) {
 581                 link_elf_error(filename, "file has no contents");
 582                 error = ENOEXEC;
 583                 goto out;
 584         }
 585         if (nsym != 1) {
 586                 /* Only allow one symbol table for now */
 587                 link_elf_error(filename, "file has no valid symbol table");
 588                 error = ENOEXEC;
 589                 goto out;
 590         }
 591         if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
 592             shdr[symstrindex].sh_type != SHT_STRTAB) {
 593                 link_elf_error(filename, "file has invalid symbol strings");
 594                 error = ENOEXEC;
 595                 goto out;
 596         }
 597
 598         /* Allocate space for tracking the load chunks */
 599         if (ef->nprogtab != 0)
 600                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
 601                     M_LINKER, M_WAITOK | M_ZERO);
 602         if (ef->nreltab != 0)
 603                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
 604                     M_LINKER, M_WAITOK | M_ZERO);
 605         if (ef->nrelatab != 0)
 606                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
 607                     M_LINKER, M_WAITOK | M_ZERO);
 608         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
 609             (ef->nreltab != 0 && ef->reltab == NULL) ||
 610             (ef->nrelatab != 0 && ef->relatab == NULL)) {
 611                 error = ENOMEM;
 612                 goto out;
 613         }
 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         if (ef->ddbsymtab == NULL) {
 621                 error = ENOMEM;
 622                 goto out;
 623         }
 624         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ef->ddbsymtab,
 625             shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
 626             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 627             &resid, td);
 628         if (error)
 629                 goto out;
 630         if (resid != 0){
 631                 error = EINVAL;
 632                 goto out;
 633         }
 634
 635         if (symstrindex == -1)
 636                 panic("lost symbol string index");
 637         /* Allocate space for and load the symbol strings */
 638         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 639         ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
 640         if (ef->ddbstrtab == NULL) {
 641                 error = ENOMEM;
 642                 goto out;
 643         }
 644         error = vn_rdwr(UIO_READ, nd.ni_vp, ef->ddbstrtab,
 645             shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
 646             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 647             &resid, td);
 648         if (error)
 649                 goto out;
 650         if (resid != 0){
 651                 error = EINVAL;
 652                 goto out;
 653         }
 654
 655         /* Do we have a string table for the section names?  */
 656         shstrindex = -1;
 657         if (hdr->e_shstrndx != 0 &&
 658             shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
 659                 shstrindex = hdr->e_shstrndx;
 660                 ef->shstrcnt = shdr[shstrindex].sh_size;
 661                 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER,
 662                     M_WAITOK);
 663                 if (ef->shstrtab == NULL) {
 664                         error = ENOMEM;
 665                         goto out;
 666                 }
 667                 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->shstrtab,
 668                     shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
 669                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 670                     &resid, td);
 671                 if (error)
 672                         goto out;
 673                 if (resid != 0){
 674                         error = EINVAL;
 675                         goto out;
 676                 }
 677         }
 678
 679         /* Size up code/data(progbits) and bss(nobits). */
 680         alignmask = 0;
 681         for (i = 0; i < hdr->e_shnum; i++) {
 682                 if (shdr[i].sh_size == 0)
 683                         continue;
 684                 switch (shdr[i].sh_type) {
 685                 case SHT_PROGBITS:
 686                 case SHT_NOBITS:
 687                         alignmask = shdr[i].sh_addralign - 1;
 688                         mapsize += alignmask;
 689                         mapsize &= ~alignmask;
 690                         mapsize += shdr[i].sh_size;
 691                         break;
 692                 }
 693         }
 694
 695         /*
 696          * We know how much space we need for the text/data/bss/etc.
 697          * This stuff needs to be in a single chunk so that profiling etc
 698          * can get the bounds and gdb can associate offsets with modules
 699          */
 700         ef->object = vm_object_allocate(OBJT_DEFAULT,
 701             round_page(mapsize) >> PAGE_SHIFT);
 702         if (ef->object == NULL) {
 703                 error = ENOMEM;
 704                 goto out;
 705         }
 706         ef->address = (caddr_t) vm_map_min(kernel_map);
 707
 708         /*
 709          * In order to satisfy amd64's architectural requirements on the
 710          * location of code and data in the kernel's address space, request a
 711          * mapping that is above the kernel.
 712          */
 713         mapbase = KERNBASE;
 714         error = vm_map_find(kernel_map, ef->object, 0, &mapbase,
 715             round_page(mapsize), TRUE, VM_PROT_ALL, VM_PROT_ALL, FALSE);
 716         if (error) {
 717                 vm_object_deallocate(ef->object);
 718                 ef->object = 0;
 719                 goto out;
 720         }
 721
 722         /* Wire the pages */
 723         error = vm_map_wire(kernel_map, mapbase,
 724             mapbase + round_page(mapsize),
 725             VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES);
 726         if (error != KERN_SUCCESS) {
 727                 error = ENOMEM;
 728                 goto out;
 729         }
 730
 731         /* Inform the kld system about the situation */
 732         lf->address = ef->address = (caddr_t)mapbase;
 733         lf->size = mapsize;
 734
 735         /*
 736          * Now load code/data(progbits), zero bss(nobits), allocate space for
 737          * and load relocs
 738          */
 739         pb = 0;
 740         rl = 0;
 741         ra = 0;
 742         alignmask = 0;
 743         for (i = 0; i < hdr->e_shnum; i++) {
 744                 if (shdr[i].sh_size == 0)
 745                         continue;
 746                 switch (shdr[i].sh_type) {
 747                 case SHT_PROGBITS:
 748                 case SHT_NOBITS:
 749                         alignmask = shdr[i].sh_addralign - 1;
 750                         mapbase += alignmask;
 751                         mapbase &= ~alignmask;
 752                         if (ef->shstrtab && shdr[i].sh_name != 0)
 753                                 ef->progtab[pb].name =
 754                                     ef->shstrtab + shdr[i].sh_name;
 755                         else if (shdr[i].sh_type == SHT_PROGBITS)
 756                                 ef->progtab[pb].name = "<<PROGBITS>>";
 757                         else
 758                                 ef->progtab[pb].name = "<<NOBITS>>";
 759                         if (ef->progtab[pb].name != NULL &&
 760                             !strcmp(ef->progtab[pb].name, "set_pcpu"))
 761                                 ef->progtab[pb].addr =
 762                                     dpcpu_alloc(shdr[i].sh_size);
 763 #ifdef VIMAGE
 764                         else if (ef->progtab[pb].name != NULL &&
 765                             !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 766                                 ef->progtab[pb].addr =
 767                                     vnet_data_alloc(shdr[i].sh_size);
 768 #endif
 769                         else
 770                                 ef->progtab[pb].addr =
 771                                     (void *)(uintptr_t)mapbase;
 772                         if (ef->progtab[pb].addr == NULL) {
 773                                 error = ENOSPC;
 774                                 goto out;
 775                         }
 776                         ef->progtab[pb].size = shdr[i].sh_size;
 777                         ef->progtab[pb].sec = i;
 778                         if (shdr[i].sh_type == SHT_PROGBITS) {
 779                                 error = vn_rdwr(UIO_READ, nd.ni_vp,
 780                                     ef->progtab[pb].addr,
 781                                     shdr[i].sh_size, shdr[i].sh_offset,
 782                                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
 783                                     NOCRED, &resid, td);
 784                                 if (error)
 785                                         goto out;
 786                                 if (resid != 0){
 787                                         error = EINVAL;
 788                                         goto out;
 789                                 }
 790                                 /* Initialize the per-cpu or vnet area. */
 791                                 if (ef->progtab[pb].addr != (void *)mapbase &&
 792                                     !strcmp(ef->progtab[pb].name, "set_pcpu"))
 793                                         dpcpu_copy(ef->progtab[pb].addr,
 794                                             shdr[i].sh_size);
 795 #ifdef VIMAGE
 796                                 else if (ef->progtab[pb].addr !=
 797                                     (void *)mapbase &&
 798                                     !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 799                                         vnet_data_copy(ef->progtab[pb].addr,
 800                                             shdr[i].sh_size);
 801 #endif
 802                         } else
 803                                 bzero(ef->progtab[pb].addr, shdr[i].sh_size);
 804
 805                         /* Update all symbol values with the offset. */
 806                         for (j = 0; j < ef->ddbsymcnt; j++) {
 807                                 es = &ef->ddbsymtab[j];
 808                                 if (es->st_shndx != i)
 809                                         continue;
 810                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 811                         }
 812                         mapbase += shdr[i].sh_size;
 813                         pb++;
 814                         break;
 815                 case SHT_REL:
 816                         ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER,
 817                             M_WAITOK);
 818                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 819                         ef->reltab[rl].sec = shdr[i].sh_info;
 820                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 821                             (void *)ef->reltab[rl].rel,
 822                             shdr[i].sh_size, shdr[i].sh_offset,
 823                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 824                             &resid, td);
 825                         if (error)
 826                                 goto out;
 827                         if (resid != 0){
 828                                 error = EINVAL;
 829                                 goto out;
 830                         }
 831                         rl++;
 832                         break;
 833                 case SHT_RELA:
 834                         ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER,
 835                             M_WAITOK);
 836                         ef->relatab[ra].nrela =
 837                             shdr[i].sh_size / sizeof(Elf_Rela);
 838                         ef->relatab[ra].sec = shdr[i].sh_info;
 839                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 840                             (void *)ef->relatab[ra].rela,
 841                             shdr[i].sh_size, shdr[i].sh_offset,
 842                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 843                             &resid, td);
 844                         if (error)
 845                                 goto out;
 846                         if (resid != 0){
 847                                 error = EINVAL;
 848                                 goto out;
 849                         }
 850                         ra++;
 851                         break;
 852                 }
 853         }
 854         if (pb != ef->nprogtab)
 855                 panic("lost progbits");
 856         if (rl != ef->nreltab)
 857                 panic("lost reltab");
 858         if (ra != ef->nrelatab)
 859                 panic("lost relatab");
 860         if (mapbase != (vm_offset_t)ef->address + mapsize)
 861                 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
 862                     (u_long)mapbase, ef->address, (u_long)mapsize,
 863                     (u_long)(vm_offset_t)ef->address + mapsize);
 864
 865         /* Local intra-module relocations */
 866         link_elf_reloc_local(lf);
 867
 868         /* Pull in dependencies */
 869         VOP_UNLOCK(nd.ni_vp, 0);
 870         error = linker_load_dependencies(lf);
 871         vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
 872         if (error)
 873                 goto out;
 874
 875         /* External relocations */
 876         error = relocate_file(ef);
 877         if (error)
 878                 goto out;
 879
 880         /* Notify MD code that a module is being loaded. */
 881         error = elf_cpu_load_file(lf);
 882         if (error)
 883                 goto out;
 884
 885         *result = lf;
 886
 887 out:
 888         VOP_UNLOCK(nd.ni_vp, 0);
 889         vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
 890         VFS_UNLOCK_GIANT(vfslocked);
 891         if (error && lf)
 892                 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 893         if (hdr)
 894                 free(hdr, M_LINKER);
 895
 896         return error;
 897 }
 898
 899 static void
 900 link_elf_unload_file(linker_file_t file)
 901 {
 902         elf_file_t ef = (elf_file_t) file;
 903         int i;
 904
 905         /* Notify MD code that a module is being unloaded. */
 906         elf_cpu_unload_file(file);
 907
 908         if (ef->progtab) {
 909                 for (i = 0; i < ef->nprogtab; i++) {
 910                         if (ef->progtab[i].size == 0)
 911                                 continue;
 912                         if (ef->progtab[i].name == NULL)
 913                                 continue;
 914                         if (!strcmp(ef->progtab[i].name, "set_pcpu"))
 915                                 dpcpu_free(ef->progtab[i].addr,
 916                                     ef->progtab[i].size);
 917 #ifdef VIMAGE
 918                         else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
 919                                 vnet_data_free(ef->progtab[i].addr,
 920                                     ef->progtab[i].size);
 921 #endif
 922                 }
 923         }
 924         if (ef->preloaded) {
 925                 if (ef->reltab)
 926                         free(ef->reltab, M_LINKER);
 927                 if (ef->relatab)
 928                         free(ef->relatab, M_LINKER);
 929                 if (ef->progtab)
 930                         free(ef->progtab, M_LINKER);
 931                 if (ef->ctftab)
 932                         free(ef->ctftab, M_LINKER);
 933                 if (ef->ctfoff)
 934                         free(ef->ctfoff, M_LINKER);
 935                 if (ef->typoff)
 936                         free(ef->typoff, M_LINKER);
 937                 if (file->filename != NULL)
 938                         preload_delete_name(file->filename);
 939                 /* XXX reclaim module memory? */
 940                 return;
 941         }
 942
 943         for (i = 0; i < ef->nreltab; i++)
 944                 if (ef->reltab[i].rel)
 945                         free(ef->reltab[i].rel, M_LINKER);
 946         for (i = 0; i < ef->nrelatab; i++)
 947                 if (ef->relatab[i].rela)
 948                         free(ef->relatab[i].rela, M_LINKER);
 949         if (ef->reltab)
 950                 free(ef->reltab, M_LINKER);
 951         if (ef->relatab)
 952                 free(ef->relatab, M_LINKER);
 953         if (ef->progtab)
 954                 free(ef->progtab, M_LINKER);
 955
 956         if (ef->object) {
 957                 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
 958                     (vm_offset_t) ef->address +
 959                     (ef->object->size << PAGE_SHIFT));
 960         }
 961         if (ef->e_shdr)
 962                 free(ef->e_shdr, M_LINKER);
 963         if (ef->ddbsymtab)
 964                 free(ef->ddbsymtab, M_LINKER);
 965         if (ef->ddbstrtab)
 966                 free(ef->ddbstrtab, M_LINKER);
 967         if (ef->shstrtab)
 968                 free(ef->shstrtab, M_LINKER);
 969         if (ef->ctftab)
 970                 free(ef->ctftab, M_LINKER);
 971         if (ef->ctfoff)
 972                 free(ef->ctfoff, M_LINKER);
 973         if (ef->typoff)
 974                 free(ef->typoff, M_LINKER);
 975 }
 976
 977 static const char *
 978 symbol_name(elf_file_t ef, Elf_Size r_info)
 979 {
 980         const Elf_Sym *ref;
 981
 982         if (ELF_R_SYM(r_info)) {
 983                 ref = ef->ddbsymtab + ELF_R_SYM(r_info);
 984                 return ef->ddbstrtab + ref->st_name;
 985         } else
 986                 return NULL;
 987 }
 988
 989 static Elf_Addr
 990 findbase(elf_file_t ef, int sec)
 991 {
 992         int i;
 993         Elf_Addr base = 0;
 994
 995         for (i = 0; i < ef->nprogtab; i++) {
 996                 if (sec == ef->progtab[i].sec) {
 997                         base = (Elf_Addr)ef->progtab[i].addr;
 998                         break;
 999                 }
1000         }
1001         return base;
1002 }
1003
1004 static int
1005 relocate_file(elf_file_t ef)
1006 {
1007         const Elf_Rel *rellim;
1008         const Elf_Rel *rel;
1009         const Elf_Rela *relalim;
1010         const Elf_Rela *rela;
1011         const char *symname;
1012         const Elf_Sym *sym;
1013         int i;
1014         Elf_Size symidx;
1015         Elf_Addr base;
1016
1017
1018         /* Perform relocations without addend if there are any: */
1019         for (i = 0; i < ef->nreltab; i++) {
1020                 rel = ef->reltab[i].rel;
1021                 if (rel == NULL)
1022                         panic("lost a reltab!");
1023                 rellim = rel + ef->reltab[i].nrel;
1024                 base = findbase(ef, ef->reltab[i].sec);
1025                 if (base == 0)
1026                         panic("lost base for reltab");
1027                 for ( ; rel < rellim; rel++) {
1028                         symidx = ELF_R_SYM(rel->r_info);
1029                         if (symidx >= ef->ddbsymcnt)
1030                                 continue;
1031                         sym = ef->ddbsymtab + symidx;
1032                         /* Local relocs are already done */
1033                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1034                                 continue;
1035                         if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL,
1036                             elf_obj_lookup)) {
1037                                 symname = symbol_name(ef, rel->r_info);
1038                                 printf("link_elf_obj: symbol %s undefined\n",
1039                                     symname);
1040                                 return ENOENT;
1041                         }
1042                 }
1043         }
1044
1045         /* Perform relocations with addend if there are any: */
1046         for (i = 0; i < ef->nrelatab; i++) {
1047                 rela = ef->relatab[i].rela;
1048                 if (rela == NULL)
1049                         panic("lost a relatab!");
1050                 relalim = rela + ef->relatab[i].nrela;
1051                 base = findbase(ef, ef->relatab[i].sec);
1052                 if (base == 0)
1053                         panic("lost base for relatab");
1054                 for ( ; rela < relalim; rela++) {
1055                         symidx = ELF_R_SYM(rela->r_info);
1056                         if (symidx >= ef->ddbsymcnt)
1057                                 continue;
1058                         sym = ef->ddbsymtab + symidx;
1059                         /* Local relocs are already done */
1060                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1061                                 continue;
1062                         if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA,
1063                             elf_obj_lookup)) {
1064                                 symname = symbol_name(ef, rela->r_info);
1065                                 printf("link_elf_obj: symbol %s undefined\n",
1066                                     symname);
1067                                 return ENOENT;
1068                         }
1069                 }
1070         }
1071
1072         return 0;
1073 }
1074
1075 static int
1076 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
1077 {
1078         elf_file_t ef = (elf_file_t) lf;
1079         const Elf_Sym *symp;
1080         const char *strp;
1081         int i;
1082
1083         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1084                 strp = ef->ddbstrtab + symp->st_name;
1085                 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
1086                         *sym = (c_linker_sym_t) symp;
1087                         return 0;
1088                 }
1089         }
1090         return ENOENT;
1091 }
1092
1093 static int
1094 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym,
1095     linker_symval_t *symval)
1096 {
1097         elf_file_t ef = (elf_file_t) lf;
1098         const Elf_Sym *es = (const Elf_Sym*) sym;
1099
1100         if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1101                 symval->name = ef->ddbstrtab + es->st_name;
1102                 symval->value = (caddr_t)es->st_value;
1103                 symval->size = es->st_size;
1104                 return 0;
1105         }
1106         return ENOENT;
1107 }
1108
1109 static int
1110 link_elf_search_symbol(linker_file_t lf, caddr_t value,
1111     c_linker_sym_t *sym, long *diffp)
1112 {
1113         elf_file_t ef = (elf_file_t) lf;
1114         u_long off = (uintptr_t) (void *) value;
1115         u_long diff = off;
1116         u_long st_value;
1117         const Elf_Sym *es;
1118         const Elf_Sym *best = 0;
1119         int i;
1120
1121         for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1122                 if (es->st_name == 0)
1123                         continue;
1124                 st_value = es->st_value;
1125                 if (off >= st_value) {
1126                         if (off - st_value < diff) {
1127                                 diff = off - st_value;
1128                                 best = es;
1129                                 if (diff == 0)
1130                                         break;
1131                         } else if (off - st_value == diff) {
1132                                 best = es;
1133                         }
1134                 }
1135         }
1136         if (best == 0)
1137                 *diffp = off;
1138         else
1139                 *diffp = diff;
1140         *sym = (c_linker_sym_t) best;
1141
1142         return 0;
1143 }
1144
1145 /*
1146  * Look up a linker set on an ELF system.
1147  */
1148 static int
1149 link_elf_lookup_set(linker_file_t lf, const char *name,
1150     void ***startp, void ***stopp, int *countp)
1151 {
1152         elf_file_t ef = (elf_file_t)lf;
1153         void **start, **stop;
1154         int i, count;
1155
1156         /* Relative to section number */
1157         for (i = 0; i < ef->nprogtab; i++) {
1158                 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
1159                     strcmp(ef->progtab[i].name + 4, name) == 0) {
1160                         start  = (void **)ef->progtab[i].addr;
1161                         stop = (void **)((char *)ef->progtab[i].addr +
1162                             ef->progtab[i].size);
1163                         count = stop - start;
1164                         if (startp)
1165                                 *startp = start;
1166                         if (stopp)
1167                                 *stopp = stop;
1168                         if (countp)
1169                                 *countp = count;
1170                         return (0);
1171                 }
1172         }
1173         return (ESRCH);
1174 }
1175
1176 static int
1177 link_elf_each_function_name(linker_file_t file,
1178     int (*callback)(const char *, void *), void *opaque)
1179 {
1180         elf_file_t ef = (elf_file_t)file;
1181         const Elf_Sym *symp;
1182         int i, error;
1183
1184         /* Exhaustive search */
1185         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1186                 if (symp->st_value != 0 &&
1187                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1188                         error = callback(ef->ddbstrtab + symp->st_name, opaque);
1189                         if (error)
1190                                 return (error);
1191                 }
1192         }
1193         return (0);
1194 }
1195
1196 static int
1197 link_elf_each_function_nameval(linker_file_t file,
1198     linker_function_nameval_callback_t callback, void *opaque)
1199 {
1200         linker_symval_t symval;
1201         elf_file_t ef = (elf_file_t)file;
1202         const Elf_Sym* symp;
1203         int i, error;
1204
1205         /* Exhaustive search */
1206         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1207                 if (symp->st_value != 0 &&
1208                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1209                         error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval);
1210                         if (error)
1211                                 return (error);
1212                         error = callback(file, i, &symval, opaque);
1213                         if (error)
1214                                 return (error);
1215                 }
1216         }
1217         return (0);
1218 }
1219
1220 /*
1221  * Symbol lookup function that can be used when the symbol index is known (ie
1222  * in relocations). It uses the symbol index instead of doing a fully fledged
1223  * hash table based lookup when such is valid. For example for local symbols.
1224  * This is not only more efficient, it's also more correct. It's not always
1225  * the case that the symbol can be found through the hash table.
1226  */
1227 static Elf_Addr
1228 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps)
1229 {
1230         elf_file_t ef = (elf_file_t)lf;
1231         const Elf_Sym *sym;
1232         const char *symbol;
1233         Elf_Addr ret;
1234
1235         /* Don't even try to lookup the symbol if the index is bogus. */
1236         if (symidx >= ef->ddbsymcnt)
1237                 return (0);
1238
1239         sym = ef->ddbsymtab + symidx;
1240
1241         /* Quick answer if there is a definition included. */
1242         if (sym->st_shndx != SHN_UNDEF)
1243                 return (sym->st_value);
1244
1245         /* If we get here, then it is undefined and needs a lookup. */
1246         switch (ELF_ST_BIND(sym->st_info)) {
1247         case STB_LOCAL:
1248                 /* Local, but undefined? huh? */
1249                 return (0);
1250
1251         case STB_GLOBAL:
1252                 /* Relative to Data or Function name */
1253                 symbol = ef->ddbstrtab + sym->st_name;
1254
1255                 /* Force a lookup failure if the symbol name is bogus. */
1256                 if (*symbol == 0)
1257                         return (0);
1258                 ret = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
1259                 return ret;
1260
1261         case STB_WEAK:
1262                 printf("link_elf_obj: Weak symbols not supported\n");
1263                 return (0);
1264
1265         default:
1266                 return (0);
1267         }
1268 }
1269
1270 static void
1271 link_elf_fix_link_set(elf_file_t ef)
1272 {
1273         static const char startn[] = "__start_";
1274         static const char stopn[] = "__stop_";
1275         Elf_Sym *sym;
1276         const char *sym_name, *linkset_name;
1277         Elf_Addr startp, stopp;
1278         Elf_Size symidx;
1279         int start, i;
1280
1281         startp = stopp = 0;
1282         for (symidx = 1 /* zero entry is special */;
1283                 symidx < ef->ddbsymcnt; symidx++) {
1284                 sym = ef->ddbsymtab + symidx;
1285                 if (sym->st_shndx != SHN_UNDEF)
1286                         continue;
1287
1288                 sym_name = ef->ddbstrtab + sym->st_name;
1289                 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
1290                         start = 1;
1291                         linkset_name = sym_name + sizeof(startn) - 1;
1292                 }
1293                 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
1294                         start = 0;
1295                         linkset_name = sym_name + sizeof(stopn) - 1;
1296                 }
1297                 else
1298                         continue;
1299
1300                 for (i = 0; i < ef->nprogtab; i++) {
1301                         if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
1302                                 startp = (Elf_Addr)ef->progtab[i].addr;
1303                                 stopp = (Elf_Addr)(startp + ef->progtab[i].size);
1304                                 break;
1305                         }
1306                 }
1307                 if (i == ef->nprogtab)
1308                         continue;
1309
1310                 sym->st_value = start ? startp : stopp;
1311                 sym->st_shndx = i;
1312         }
1313 }
1314
1315 static void
1316 link_elf_reloc_local(linker_file_t lf)
1317 {
1318         elf_file_t ef = (elf_file_t)lf;
1319         const Elf_Rel *rellim;
1320         const Elf_Rel *rel;
1321         const Elf_Rela *relalim;
1322         const Elf_Rela *rela;
1323         const Elf_Sym *sym;
1324         Elf_Addr base;
1325         int i;
1326         Elf_Size symidx;
1327
1328         link_elf_fix_link_set(ef);
1329
1330         /* Perform relocations without addend if there are any: */
1331         for (i = 0; i < ef->nreltab; i++) {
1332                 rel = ef->reltab[i].rel;
1333                 if (rel == NULL)
1334                         panic("lost a reltab!");
1335                 rellim = rel + ef->reltab[i].nrel;
1336                 base = findbase(ef, ef->reltab[i].sec);
1337                 if (base == 0)
1338                         panic("lost base for reltab");
1339                 for ( ; rel < rellim; rel++) {
1340                         symidx = ELF_R_SYM(rel->r_info);
1341                         if (symidx >= ef->ddbsymcnt)
1342                                 continue;
1343                         sym = ef->ddbsymtab + symidx;
1344                         /* Only do local relocs */
1345                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1346                                 continue;
1347                         elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
1348                             elf_obj_lookup);
1349                 }
1350         }
1351
1352         /* Perform relocations with addend if there are any: */
1353         for (i = 0; i < ef->nrelatab; i++) {
1354                 rela = ef->relatab[i].rela;
1355                 if (rela == NULL)
1356                         panic("lost a relatab!");
1357                 relalim = rela + ef->relatab[i].nrela;
1358                 base = findbase(ef, ef->relatab[i].sec);
1359                 if (base == 0)
1360                         panic("lost base for relatab");
1361                 for ( ; rela < relalim; rela++) {
1362                         symidx = ELF_R_SYM(rela->r_info);
1363                         if (symidx >= ef->ddbsymcnt)
1364                                 continue;
1365                         sym = ef->ddbsymtab + symidx;
1366                         /* Only do local relocs */
1367                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1368                                 continue;
1369                         elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
1370                             elf_obj_lookup);
1371                 }
1372         }
1373 }
1374
1375 static long
1376 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
1377 {
1378     elf_file_t ef = (elf_file_t)lf;
1379
1380     *symtab = ef->ddbsymtab;
1381
1382     if (*symtab == NULL)
1383         return (0);
1384
1385     return (ef->ddbsymcnt);
1386 }
1387
1388 static long
1389 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
1390 {
1391     elf_file_t ef = (elf_file_t)lf;
1392
1393     *strtab = ef->ddbstrtab;
1394
1395     if (*strtab == NULL)
1396         return (0);
1397
1398     return (ef->ddbstrcnt);
1399 }