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, DPCPU_SETNAME)) {
 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         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)hdr, sizeof(*hdr), 0,
 480             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 481             &resid, td);
 482         if (error)
 483                 goto out;
 484         if (resid != 0){
 485                 error = ENOEXEC;
 486                 goto out;
 487         }
 488
 489         if (!IS_ELF(*hdr)) {
 490                 error = ENOEXEC;
 491                 goto out;
 492         }
 493
 494         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
 495             || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
 496                 link_elf_error(filename, "Unsupported file layout");
 497                 error = ENOEXEC;
 498                 goto out;
 499         }
 500         if (hdr->e_ident[EI_VERSION] != EV_CURRENT
 501             || hdr->e_version != EV_CURRENT) {
 502                 link_elf_error(filename, "Unsupported file version");
 503                 error = ENOEXEC;
 504                 goto out;
 505         }
 506         if (hdr->e_type != ET_REL) {
 507                 error = ENOSYS;
 508                 goto out;
 509         }
 510         if (hdr->e_machine != ELF_TARG_MACH) {
 511                 link_elf_error(filename, "Unsupported machine");
 512                 error = ENOEXEC;
 513                 goto out;
 514         }
 515
 516         lf = linker_make_file(filename, &link_elf_class);
 517         if (!lf) {
 518                 error = ENOMEM;
 519                 goto out;
 520         }
 521         ef = (elf_file_t) lf;
 522         ef->nprogtab = 0;
 523         ef->e_shdr = 0;
 524         ef->nreltab = 0;
 525         ef->nrelatab = 0;
 526
 527         /* Allocate and read in the section header */
 528         nbytes = hdr->e_shnum * hdr->e_shentsize;
 529         if (nbytes == 0 || hdr->e_shoff == 0 ||
 530             hdr->e_shentsize != sizeof(Elf_Shdr)) {
 531                 error = ENOEXEC;
 532                 goto out;
 533         }
 534         shdr = malloc(nbytes, M_LINKER, M_WAITOK);
 535         ef->e_shdr = shdr;
 536         error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shdr, nbytes, hdr->e_shoff,
 537             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td);
 538         if (error)
 539                 goto out;
 540         if (resid) {
 541                 error = ENOEXEC;
 542                 goto out;
 543         }
 544
 545         /* Scan the section header for information and table sizing. */
 546         nsym = 0;
 547         symtabindex = -1;
 548         symstrindex = -1;
 549         for (i = 0; i < hdr->e_shnum; i++) {
 550                 if (shdr[i].sh_size == 0)
 551                         continue;
 552                 switch (shdr[i].sh_type) {
 553                 case SHT_PROGBITS:
 554                 case SHT_NOBITS:
 555                         ef->nprogtab++;
 556                         break;
 557                 case SHT_SYMTAB:
 558                         nsym++;
 559                         symtabindex = i;
 560                         symstrindex = shdr[i].sh_link;
 561                         break;
 562                 case SHT_REL:
 563                         ef->nreltab++;
 564                         break;
 565                 case SHT_RELA:
 566                         ef->nrelatab++;
 567                         break;
 568                 case SHT_STRTAB:
 569                         break;
 570                 }
 571         }
 572         if (ef->nprogtab == 0) {
 573                 link_elf_error(filename, "file has no contents");
 574                 error = ENOEXEC;
 575                 goto out;
 576         }
 577         if (nsym != 1) {
 578                 /* Only allow one symbol table for now */
 579                 link_elf_error(filename, "file has no valid symbol table");
 580                 error = ENOEXEC;
 581                 goto out;
 582         }
 583         if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
 584             shdr[symstrindex].sh_type != SHT_STRTAB) {
 585                 link_elf_error(filename, "file has invalid symbol strings");
 586                 error = ENOEXEC;
 587                 goto out;
 588         }
 589
 590         /* Allocate space for tracking the load chunks */
 591         if (ef->nprogtab != 0)
 592                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
 593                     M_LINKER, M_WAITOK | M_ZERO);
 594         if (ef->nreltab != 0)
 595                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
 596                     M_LINKER, M_WAITOK | M_ZERO);
 597         if (ef->nrelatab != 0)
 598                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
 599                     M_LINKER, M_WAITOK | M_ZERO);
 600
 601         if (symtabindex == -1)
 602                 panic("lost symbol table index");
 603         /* Allocate space for and load the symbol table */
 604         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
 605         ef->ddbsymtab = malloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK);
 606         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ef->ddbsymtab,
 607             shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
 608             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 609             &resid, td);
 610         if (error)
 611                 goto out;
 612         if (resid != 0){
 613                 error = EINVAL;
 614                 goto out;
 615         }
 616
 617         if (symstrindex == -1)
 618                 panic("lost symbol string index");
 619         /* Allocate space for and load the symbol strings */
 620         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 621         ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
 622         error = vn_rdwr(UIO_READ, nd.ni_vp, ef->ddbstrtab,
 623             shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
 624             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 625             &resid, td);
 626         if (error)
 627                 goto out;
 628         if (resid != 0){
 629                 error = EINVAL;
 630                 goto out;
 631         }
 632
 633         /* Do we have a string table for the section names?  */
 634         shstrindex = -1;
 635         if (hdr->e_shstrndx != 0 &&
 636             shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
 637                 shstrindex = hdr->e_shstrndx;
 638                 ef->shstrcnt = shdr[shstrindex].sh_size;
 639                 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER,
 640                     M_WAITOK);
 641                 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->shstrtab,
 642                     shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
 643                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 644                     &resid, td);
 645                 if (error)
 646                         goto out;
 647                 if (resid != 0){
 648                         error = EINVAL;
 649                         goto out;
 650                 }
 651         }
 652
 653         /* Size up code/data(progbits) and bss(nobits). */
 654         alignmask = 0;
 655         for (i = 0; i < hdr->e_shnum; i++) {
 656                 if (shdr[i].sh_size == 0)
 657                         continue;
 658                 switch (shdr[i].sh_type) {
 659                 case SHT_PROGBITS:
 660                 case SHT_NOBITS:
 661                         alignmask = shdr[i].sh_addralign - 1;
 662                         mapsize += alignmask;
 663                         mapsize &= ~alignmask;
 664                         mapsize += shdr[i].sh_size;
 665                         break;
 666                 }
 667         }
 668
 669         /*
 670          * We know how much space we need for the text/data/bss/etc.
 671          * This stuff needs to be in a single chunk so that profiling etc
 672          * can get the bounds and gdb can associate offsets with modules
 673          */
 674         ef->object = vm_object_allocate(OBJT_DEFAULT,
 675             round_page(mapsize) >> PAGE_SHIFT);
 676         if (ef->object == NULL) {
 677                 error = ENOMEM;
 678                 goto out;
 679         }
 680         ef->address = (caddr_t) vm_map_min(kernel_map);
 681
 682         /*
 683          * In order to satisfy amd64's architectural requirements on the
 684          * location of code and data in the kernel's address space, request a
 685          * mapping that is above the kernel.
 686          */
 687         mapbase = KERNBASE;
 688         error = vm_map_find(kernel_map, ef->object, 0, &mapbase,
 689             round_page(mapsize), TRUE, VM_PROT_ALL, VM_PROT_ALL, FALSE);
 690         if (error) {
 691                 vm_object_deallocate(ef->object);
 692                 ef->object = 0;
 693                 goto out;
 694         }
 695
 696         /* Wire the pages */
 697         error = vm_map_wire(kernel_map, mapbase,
 698             mapbase + round_page(mapsize),
 699             VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES);
 700         if (error != KERN_SUCCESS) {
 701                 error = ENOMEM;
 702                 goto out;
 703         }
 704
 705         /* Inform the kld system about the situation */
 706         lf->address = ef->address = (caddr_t)mapbase;
 707         lf->size = mapsize;
 708
 709         /*
 710          * Now load code/data(progbits), zero bss(nobits), allocate space for
 711          * and load relocs
 712          */
 713         pb = 0;
 714         rl = 0;
 715         ra = 0;
 716         alignmask = 0;
 717         for (i = 0; i < hdr->e_shnum; i++) {
 718                 if (shdr[i].sh_size == 0)
 719                         continue;
 720                 switch (shdr[i].sh_type) {
 721                 case SHT_PROGBITS:
 722                 case SHT_NOBITS:
 723                         alignmask = shdr[i].sh_addralign - 1;
 724                         mapbase += alignmask;
 725                         mapbase &= ~alignmask;
 726                         if (ef->shstrtab && shdr[i].sh_name != 0)
 727                                 ef->progtab[pb].name =
 728                                     ef->shstrtab + shdr[i].sh_name;
 729                         else if (shdr[i].sh_type == SHT_PROGBITS)
 730                                 ef->progtab[pb].name = "<<PROGBITS>>";
 731                         else
 732                                 ef->progtab[pb].name = "<<NOBITS>>";
 733                         if (ef->progtab[pb].name != NULL &&
 734                             !strcmp(ef->progtab[pb].name, DPCPU_SETNAME))
 735                                 ef->progtab[pb].addr =
 736                                     dpcpu_alloc(shdr[i].sh_size);
 737 #ifdef VIMAGE
 738                         else if (ef->progtab[pb].name != NULL &&
 739                             !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 740                                 ef->progtab[pb].addr =
 741                                     vnet_data_alloc(shdr[i].sh_size);
 742 #endif
 743                         else
 744                                 ef->progtab[pb].addr =
 745                                     (void *)(uintptr_t)mapbase;
 746                         if (ef->progtab[pb].addr == NULL) {
 747                                 error = ENOSPC;
 748                                 goto out;
 749                         }
 750                         ef->progtab[pb].size = shdr[i].sh_size;
 751                         ef->progtab[pb].sec = i;
 752                         if (shdr[i].sh_type == SHT_PROGBITS) {
 753                                 error = vn_rdwr(UIO_READ, nd.ni_vp,
 754                                     ef->progtab[pb].addr,
 755                                     shdr[i].sh_size, shdr[i].sh_offset,
 756                                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
 757                                     NOCRED, &resid, td);
 758                                 if (error)
 759                                         goto out;
 760                                 if (resid != 0){
 761                                         error = EINVAL;
 762                                         goto out;
 763                                 }
 764                                 /* Initialize the per-cpu or vnet area. */
 765                                 if (ef->progtab[pb].addr != (void *)mapbase &&
 766                                     !strcmp(ef->progtab[pb].name, DPCPU_SETNAME))
 767                                         dpcpu_copy(ef->progtab[pb].addr,
 768                                             shdr[i].sh_size);
 769 #ifdef VIMAGE
 770                                 else if (ef->progtab[pb].addr !=
 771                                     (void *)mapbase &&
 772                                     !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 773                                         vnet_data_copy(ef->progtab[pb].addr,
 774                                             shdr[i].sh_size);
 775 #endif
 776                         } else
 777                                 bzero(ef->progtab[pb].addr, shdr[i].sh_size);
 778
 779                         /* Update all symbol values with the offset. */
 780                         for (j = 0; j < ef->ddbsymcnt; j++) {
 781                                 es = &ef->ddbsymtab[j];
 782                                 if (es->st_shndx != i)
 783                                         continue;
 784                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 785                         }
 786                         mapbase += shdr[i].sh_size;
 787                         pb++;
 788                         break;
 789                 case SHT_REL:
 790                         ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER,
 791                             M_WAITOK);
 792                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 793                         ef->reltab[rl].sec = shdr[i].sh_info;
 794                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 795                             (void *)ef->reltab[rl].rel,
 796                             shdr[i].sh_size, shdr[i].sh_offset,
 797                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 798                             &resid, td);
 799                         if (error)
 800                                 goto out;
 801                         if (resid != 0){
 802                                 error = EINVAL;
 803                                 goto out;
 804                         }
 805                         rl++;
 806                         break;
 807                 case SHT_RELA:
 808                         ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER,
 809                             M_WAITOK);
 810                         ef->relatab[ra].nrela =
 811                             shdr[i].sh_size / sizeof(Elf_Rela);
 812                         ef->relatab[ra].sec = shdr[i].sh_info;
 813                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 814                             (void *)ef->relatab[ra].rela,
 815                             shdr[i].sh_size, shdr[i].sh_offset,
 816                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 817                             &resid, td);
 818                         if (error)
 819                                 goto out;
 820                         if (resid != 0){
 821                                 error = EINVAL;
 822                                 goto out;
 823                         }
 824                         ra++;
 825                         break;
 826                 }
 827         }
 828         if (pb != ef->nprogtab)
 829                 panic("lost progbits");
 830         if (rl != ef->nreltab)
 831                 panic("lost reltab");
 832         if (ra != ef->nrelatab)
 833                 panic("lost relatab");
 834         if (mapbase != (vm_offset_t)ef->address + mapsize)
 835                 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
 836                     (u_long)mapbase, ef->address, (u_long)mapsize,
 837                     (u_long)(vm_offset_t)ef->address + mapsize);
 838
 839         /* Local intra-module relocations */
 840         link_elf_reloc_local(lf);
 841
 842         /* Pull in dependencies */
 843         VOP_UNLOCK(nd.ni_vp, 0);
 844         error = linker_load_dependencies(lf);
 845         vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
 846         if (error)
 847                 goto out;
 848
 849         /* External relocations */
 850         error = relocate_file(ef);
 851         if (error)
 852                 goto out;
 853
 854         /* Notify MD code that a module is being loaded. */
 855         error = elf_cpu_load_file(lf);
 856         if (error)
 857                 goto out;
 858
 859         *result = lf;
 860
 861 out:
 862         VOP_UNLOCK(nd.ni_vp, 0);
 863         vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
 864         VFS_UNLOCK_GIANT(vfslocked);
 865         if (error && lf)
 866                 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 867         if (hdr)
 868                 free(hdr, M_LINKER);
 869
 870         return error;
 871 }
 872
 873 static void
 874 link_elf_unload_file(linker_file_t file)
 875 {
 876         elf_file_t ef = (elf_file_t) file;
 877         int i;
 878
 879         /* Notify MD code that a module is being unloaded. */
 880         elf_cpu_unload_file(file);
 881
 882         if (ef->progtab) {
 883                 for (i = 0; i < ef->nprogtab; i++) {
 884                         if (ef->progtab[i].size == 0)
 885                                 continue;
 886                         if (ef->progtab[i].name == NULL)
 887                                 continue;
 888                         if (!strcmp(ef->progtab[i].name, DPCPU_SETNAME))
 889                                 dpcpu_free(ef->progtab[i].addr,
 890                                     ef->progtab[i].size);
 891 #ifdef VIMAGE
 892                         else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
 893                                 vnet_data_free(ef->progtab[i].addr,
 894                                     ef->progtab[i].size);
 895 #endif
 896                 }
 897         }
 898         if (ef->preloaded) {
 899                 if (ef->reltab)
 900                         free(ef->reltab, M_LINKER);
 901                 if (ef->relatab)
 902                         free(ef->relatab, M_LINKER);
 903                 if (ef->progtab)
 904                         free(ef->progtab, M_LINKER);
 905                 if (ef->ctftab)
 906                         free(ef->ctftab, M_LINKER);
 907                 if (ef->ctfoff)
 908                         free(ef->ctfoff, M_LINKER);
 909                 if (ef->typoff)
 910                         free(ef->typoff, M_LINKER);
 911                 if (file->filename != NULL)
 912                         preload_delete_name(file->filename);
 913                 /* XXX reclaim module memory? */
 914                 return;
 915         }
 916
 917         for (i = 0; i < ef->nreltab; i++)
 918                 if (ef->reltab[i].rel)
 919                         free(ef->reltab[i].rel, M_LINKER);
 920         for (i = 0; i < ef->nrelatab; i++)
 921                 if (ef->relatab[i].rela)
 922                         free(ef->relatab[i].rela, M_LINKER);
 923         if (ef->reltab)
 924                 free(ef->reltab, M_LINKER);
 925         if (ef->relatab)
 926                 free(ef->relatab, M_LINKER);
 927         if (ef->progtab)
 928                 free(ef->progtab, M_LINKER);
 929
 930         if (ef->object) {
 931                 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
 932                     (vm_offset_t) ef->address +
 933                     (ef->object->size << PAGE_SHIFT));
 934         }
 935         if (ef->e_shdr)
 936                 free(ef->e_shdr, M_LINKER);
 937         if (ef->ddbsymtab)
 938                 free(ef->ddbsymtab, M_LINKER);
 939         if (ef->ddbstrtab)
 940                 free(ef->ddbstrtab, M_LINKER);
 941         if (ef->shstrtab)
 942                 free(ef->shstrtab, M_LINKER);
 943         if (ef->ctftab)
 944                 free(ef->ctftab, M_LINKER);
 945         if (ef->ctfoff)
 946                 free(ef->ctfoff, M_LINKER);
 947         if (ef->typoff)
 948                 free(ef->typoff, M_LINKER);
 949 }
 950
 951 static const char *
 952 symbol_name(elf_file_t ef, Elf_Size r_info)
 953 {
 954         const Elf_Sym *ref;
 955
 956         if (ELF_R_SYM(r_info)) {
 957                 ref = ef->ddbsymtab + ELF_R_SYM(r_info);
 958                 return ef->ddbstrtab + ref->st_name;
 959         } else
 960                 return NULL;
 961 }
 962
 963 static Elf_Addr
 964 findbase(elf_file_t ef, int sec)
 965 {
 966         int i;
 967         Elf_Addr base = 0;
 968
 969         for (i = 0; i < ef->nprogtab; i++) {
 970                 if (sec == ef->progtab[i].sec) {
 971                         base = (Elf_Addr)ef->progtab[i].addr;
 972                         break;
 973                 }
 974         }
 975         return base;
 976 }
 977
 978 static int
 979 relocate_file(elf_file_t ef)
 980 {
 981         const Elf_Rel *rellim;
 982         const Elf_Rel *rel;
 983         const Elf_Rela *relalim;
 984         const Elf_Rela *rela;
 985         const char *symname;
 986         const Elf_Sym *sym;
 987         int i;
 988         Elf_Size symidx;
 989         Elf_Addr base;
 990
 991
 992         /* Perform relocations without addend if there are any: */
 993         for (i = 0; i < ef->nreltab; i++) {
 994                 rel = ef->reltab[i].rel;
 995                 if (rel == NULL)
 996                         panic("lost a reltab!");
 997                 rellim = rel + ef->reltab[i].nrel;
 998                 base = findbase(ef, ef->reltab[i].sec);
 999                 if (base == 0)
1000                         panic("lost base for reltab");
1001                 for ( ; rel < rellim; rel++) {
1002                         symidx = ELF_R_SYM(rel->r_info);
1003                         if (symidx >= ef->ddbsymcnt)
1004                                 continue;
1005                         sym = ef->ddbsymtab + symidx;
1006                         /* Local relocs are already done */
1007                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1008                                 continue;
1009                         if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL,
1010                             elf_obj_lookup)) {
1011                                 symname = symbol_name(ef, rel->r_info);
1012                                 printf("link_elf_obj: symbol %s undefined\n",
1013                                     symname);
1014                                 return ENOENT;
1015                         }
1016                 }
1017         }
1018
1019         /* Perform relocations with addend if there are any: */
1020         for (i = 0; i < ef->nrelatab; i++) {
1021                 rela = ef->relatab[i].rela;
1022                 if (rela == NULL)
1023                         panic("lost a relatab!");
1024                 relalim = rela + ef->relatab[i].nrela;
1025                 base = findbase(ef, ef->relatab[i].sec);
1026                 if (base == 0)
1027                         panic("lost base for relatab");
1028                 for ( ; rela < relalim; rela++) {
1029                         symidx = ELF_R_SYM(rela->r_info);
1030                         if (symidx >= ef->ddbsymcnt)
1031                                 continue;
1032                         sym = ef->ddbsymtab + symidx;
1033                         /* Local relocs are already done */
1034                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1035                                 continue;
1036                         if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA,
1037                             elf_obj_lookup)) {
1038                                 symname = symbol_name(ef, rela->r_info);
1039                                 printf("link_elf_obj: symbol %s undefined\n",
1040                                     symname);
1041                                 return ENOENT;
1042                         }
1043                 }
1044         }
1045
1046         return 0;
1047 }
1048
1049 static int
1050 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
1051 {
1052         elf_file_t ef = (elf_file_t) lf;
1053         const Elf_Sym *symp;
1054         const char *strp;
1055         int i;
1056
1057         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1058                 strp = ef->ddbstrtab + symp->st_name;
1059                 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
1060                         *sym = (c_linker_sym_t) symp;
1061                         return 0;
1062                 }
1063         }
1064         return ENOENT;
1065 }
1066
1067 static int
1068 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym,
1069     linker_symval_t *symval)
1070 {
1071         elf_file_t ef = (elf_file_t) lf;
1072         const Elf_Sym *es = (const Elf_Sym*) sym;
1073
1074         if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1075                 symval->name = ef->ddbstrtab + es->st_name;
1076                 symval->value = (caddr_t)es->st_value;
1077                 symval->size = es->st_size;
1078                 return 0;
1079         }
1080         return ENOENT;
1081 }
1082
1083 static int
1084 link_elf_search_symbol(linker_file_t lf, caddr_t value,
1085     c_linker_sym_t *sym, long *diffp)
1086 {
1087         elf_file_t ef = (elf_file_t) lf;
1088         u_long off = (uintptr_t) (void *) value;
1089         u_long diff = off;
1090         u_long st_value;
1091         const Elf_Sym *es;
1092         const Elf_Sym *best = 0;
1093         int i;
1094
1095         for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1096                 if (es->st_name == 0)
1097                         continue;
1098                 st_value = es->st_value;
1099                 if (off >= st_value) {
1100                         if (off - st_value < diff) {
1101                                 diff = off - st_value;
1102                                 best = es;
1103                                 if (diff == 0)
1104                                         break;
1105                         } else if (off - st_value == diff) {
1106                                 best = es;
1107                         }
1108                 }
1109         }
1110         if (best == 0)
1111                 *diffp = off;
1112         else
1113                 *diffp = diff;
1114         *sym = (c_linker_sym_t) best;
1115
1116         return 0;
1117 }
1118
1119 /*
1120  * Look up a linker set on an ELF system.
1121  */
1122 static int
1123 link_elf_lookup_set(linker_file_t lf, const char *name,
1124     void ***startp, void ***stopp, int *countp)
1125 {
1126         elf_file_t ef = (elf_file_t)lf;
1127         void **start, **stop;
1128         int i, count;
1129
1130         /* Relative to section number */
1131         for (i = 0; i < ef->nprogtab; i++) {
1132                 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
1133                     strcmp(ef->progtab[i].name + 4, name) == 0) {
1134                         start  = (void **)ef->progtab[i].addr;
1135                         stop = (void **)((char *)ef->progtab[i].addr +
1136                             ef->progtab[i].size);
1137                         count = stop - start;
1138                         if (startp)
1139                                 *startp = start;
1140                         if (stopp)
1141                                 *stopp = stop;
1142                         if (countp)
1143                                 *countp = count;
1144                         return (0);
1145                 }
1146         }
1147         return (ESRCH);
1148 }
1149
1150 static int
1151 link_elf_each_function_name(linker_file_t file,
1152     int (*callback)(const char *, void *), void *opaque)
1153 {
1154         elf_file_t ef = (elf_file_t)file;
1155         const Elf_Sym *symp;
1156         int i, error;
1157
1158         /* Exhaustive search */
1159         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1160                 if (symp->st_value != 0 &&
1161                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1162                         error = callback(ef->ddbstrtab + symp->st_name, opaque);
1163                         if (error)
1164                                 return (error);
1165                 }
1166         }
1167         return (0);
1168 }
1169
1170 static int
1171 link_elf_each_function_nameval(linker_file_t file,
1172     linker_function_nameval_callback_t callback, void *opaque)
1173 {
1174         linker_symval_t symval;
1175         elf_file_t ef = (elf_file_t)file;
1176         const Elf_Sym* symp;
1177         int i, error;
1178
1179         /* Exhaustive search */
1180         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1181                 if (symp->st_value != 0 &&
1182                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1183                         error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval);
1184                         if (error)
1185                                 return (error);
1186                         error = callback(file, i, &symval, opaque);
1187                         if (error)
1188                                 return (error);
1189                 }
1190         }
1191         return (0);
1192 }
1193
1194 /*
1195  * Symbol lookup function that can be used when the symbol index is known (ie
1196  * in relocations). It uses the symbol index instead of doing a fully fledged
1197  * hash table based lookup when such is valid. For example for local symbols.
1198  * This is not only more efficient, it's also more correct. It's not always
1199  * the case that the symbol can be found through the hash table.
1200  */
1201 static Elf_Addr
1202 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps)
1203 {
1204         elf_file_t ef = (elf_file_t)lf;
1205         const Elf_Sym *sym;
1206         const char *symbol;
1207         Elf_Addr ret;
1208
1209         /* Don't even try to lookup the symbol if the index is bogus. */
1210         if (symidx >= ef->ddbsymcnt)
1211                 return (0);
1212
1213         sym = ef->ddbsymtab + symidx;
1214
1215         /* Quick answer if there is a definition included. */
1216         if (sym->st_shndx != SHN_UNDEF)
1217                 return (sym->st_value);
1218
1219         /* If we get here, then it is undefined and needs a lookup. */
1220         switch (ELF_ST_BIND(sym->st_info)) {
1221         case STB_LOCAL:
1222                 /* Local, but undefined? huh? */
1223                 return (0);
1224
1225         case STB_GLOBAL:
1226                 /* Relative to Data or Function name */
1227                 symbol = ef->ddbstrtab + sym->st_name;
1228
1229                 /* Force a lookup failure if the symbol name is bogus. */
1230                 if (*symbol == 0)
1231                         return (0);
1232                 ret = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
1233                 return ret;
1234
1235         case STB_WEAK:
1236                 printf("link_elf_obj: Weak symbols not supported\n");
1237                 return (0);
1238
1239         default:
1240                 return (0);
1241         }
1242 }
1243
1244 static void
1245 link_elf_fix_link_set(elf_file_t ef)
1246 {
1247         static const char startn[] = "__start_";
1248         static const char stopn[] = "__stop_";
1249         Elf_Sym *sym;
1250         const char *sym_name, *linkset_name;
1251         Elf_Addr startp, stopp;
1252         Elf_Size symidx;
1253         int start, i;
1254
1255         startp = stopp = 0;
1256         for (symidx = 1 /* zero entry is special */;
1257                 symidx < ef->ddbsymcnt; symidx++) {
1258                 sym = ef->ddbsymtab + symidx;
1259                 if (sym->st_shndx != SHN_UNDEF)
1260                         continue;
1261
1262                 sym_name = ef->ddbstrtab + sym->st_name;
1263                 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
1264                         start = 1;
1265                         linkset_name = sym_name + sizeof(startn) - 1;
1266                 }
1267                 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
1268                         start = 0;
1269                         linkset_name = sym_name + sizeof(stopn) - 1;
1270                 }
1271                 else
1272                         continue;
1273
1274                 for (i = 0; i < ef->nprogtab; i++) {
1275                         if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
1276                                 startp = (Elf_Addr)ef->progtab[i].addr;
1277                                 stopp = (Elf_Addr)(startp + ef->progtab[i].size);
1278                                 break;
1279                         }
1280                 }
1281                 if (i == ef->nprogtab)
1282                         continue;
1283
1284                 sym->st_value = start ? startp : stopp;
1285                 sym->st_shndx = i;
1286         }
1287 }
1288
1289 static void
1290 link_elf_reloc_local(linker_file_t lf)
1291 {
1292         elf_file_t ef = (elf_file_t)lf;
1293         const Elf_Rel *rellim;
1294         const Elf_Rel *rel;
1295         const Elf_Rela *relalim;
1296         const Elf_Rela *rela;
1297         const Elf_Sym *sym;
1298         Elf_Addr base;
1299         int i;
1300         Elf_Size symidx;
1301
1302         link_elf_fix_link_set(ef);
1303
1304         /* Perform relocations without addend if there are any: */
1305         for (i = 0; i < ef->nreltab; i++) {
1306                 rel = ef->reltab[i].rel;
1307                 if (rel == NULL)
1308                         panic("lost a reltab!");
1309                 rellim = rel + ef->reltab[i].nrel;
1310                 base = findbase(ef, ef->reltab[i].sec);
1311                 if (base == 0)
1312                         panic("lost base for reltab");
1313                 for ( ; rel < rellim; rel++) {
1314                         symidx = ELF_R_SYM(rel->r_info);
1315                         if (symidx >= ef->ddbsymcnt)
1316                                 continue;
1317                         sym = ef->ddbsymtab + symidx;
1318                         /* Only do local relocs */
1319                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1320                                 continue;
1321                         elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
1322                             elf_obj_lookup);
1323                 }
1324         }
1325
1326         /* Perform relocations with addend if there are any: */
1327         for (i = 0; i < ef->nrelatab; i++) {
1328                 rela = ef->relatab[i].rela;
1329                 if (rela == NULL)
1330                         panic("lost a relatab!");
1331                 relalim = rela + ef->relatab[i].nrela;
1332                 base = findbase(ef, ef->relatab[i].sec);
1333                 if (base == 0)
1334                         panic("lost base for relatab");
1335                 for ( ; rela < relalim; rela++) {
1336                         symidx = ELF_R_SYM(rela->r_info);
1337                         if (symidx >= ef->ddbsymcnt)
1338                                 continue;
1339                         sym = ef->ddbsymtab + symidx;
1340                         /* Only do local relocs */
1341                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1342                                 continue;
1343                         elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
1344                             elf_obj_lookup);
1345                 }
1346         }
1347 }
1348
1349 static long
1350 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
1351 {
1352     elf_file_t ef = (elf_file_t)lf;
1353
1354     *symtab = ef->ddbsymtab;
1355
1356     if (*symtab == NULL)
1357         return (0);
1358
1359     return (ef->ddbsymcnt);
1360 }
1361
1362 static long
1363 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
1364 {
1365     elf_file_t ef = (elf_file_t)lf;
1366
1367     *strtab = ef->ddbstrtab;
1368
1369     if (*strtab == NULL)
1370         return (0);
1371
1372     return (ef->ddbstrcnt);
1373 }