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                         } else if (ef->progtab[pb].name != NULL &&
 367                             !strcmp(ef->progtab[pb].name, ".ctors")) {
 368                                 lf->ctors_addr = ef->progtab[pb].addr;
 369                                 lf->ctors_size = shdr[i].sh_size;
 370                         }
 371
 372                         /* Update all symbol values with the offset. */
 373                         for (j = 0; j < ef->ddbsymcnt; j++) {
 374                                 es = &ef->ddbsymtab[j];
 375                                 if (es->st_shndx != i)
 376                                         continue;
 377                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 378                         }
 379                         pb++;
 380                         break;
 381                 case SHT_REL:
 382                         ef->reltab[rl].rel = (Elf_Rel *)shdr[i].sh_addr;
 383                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 384                         ef->reltab[rl].sec = shdr[i].sh_info;
 385                         rl++;
 386                         break;
 387                 case SHT_RELA:
 388                         ef->relatab[ra].rela = (Elf_Rela *)shdr[i].sh_addr;
 389                         ef->relatab[ra].nrela =
 390                             shdr[i].sh_size / sizeof(Elf_Rela);
 391                         ef->relatab[ra].sec = shdr[i].sh_info;
 392                         ra++;
 393                         break;
 394                 }
 395         }
 396         if (pb != ef->nprogtab)
 397                 panic("lost progbits");
 398         if (rl != ef->nreltab)
 399                 panic("lost reltab");
 400         if (ra != ef->nrelatab)
 401                 panic("lost relatab");
 402
 403         /* Local intra-module relocations */
 404         link_elf_reloc_local(lf);
 405
 406         *result = lf;
 407         return (0);
 408
 409 out:
 410         /* preload not done this way */
 411         linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 412         return (error);
 413 }
 414
 415 static void
 416 link_elf_invoke_ctors(caddr_t addr, size_t size)
 417 {
 418         void (**ctor)(void);
 419         size_t i, cnt;
 420
 421         if (addr == NULL || size == 0)
 422                 return;
 423         cnt = size / sizeof(*ctor);
 424         ctor = (void *)addr;
 425         for (i = 0; i < cnt; i++) {
 426                 if (ctor[i] != NULL)
 427                         (*ctor[i])();
 428         }
 429 }
 430
 431 static int
 432 link_elf_link_preload_finish(linker_file_t lf)
 433 {
 434         elf_file_t ef;
 435         int error;
 436
 437         ef = (elf_file_t)lf;
 438         error = relocate_file(ef);
 439         if (error)
 440                 return error;
 441
 442         /* Notify MD code that a module is being loaded. */
 443         error = elf_cpu_load_file(lf);
 444         if (error)
 445                 return (error);
 446
 447         /* Invoke .ctors */
 448         link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size);
 449         return (0);
 450 }
 451
 452 static int
 453 link_elf_load_file(linker_class_t cls, const char *filename,
 454     linker_file_t *result)
 455 {
 456         struct nameidata nd;
 457         struct thread *td = curthread;  /* XXX */
 458         Elf_Ehdr *hdr;
 459         Elf_Shdr *shdr;
 460         Elf_Sym *es;
 461         int nbytes, i, j;
 462         vm_offset_t mapbase;
 463         size_t mapsize;
 464         int error = 0;
 465         ssize_t resid;
 466         int flags;
 467         elf_file_t ef;
 468         linker_file_t lf;
 469         int symtabindex;
 470         int symstrindex;
 471         int shstrindex;
 472         int nsym;
 473         int pb, rl, ra;
 474         int alignmask;
 475
 476         shdr = NULL;
 477         lf = NULL;
 478         mapsize = 0;
 479         hdr = NULL;
 480
 481         NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td);
 482         flags = FREAD;
 483         error = vn_open(&nd, &flags, 0, NULL);
 484         if (error)
 485                 return error;
 486         NDFREE(&nd, NDF_ONLY_PNBUF);
 487         if (nd.ni_vp->v_type != VREG) {
 488                 error = ENOEXEC;
 489                 goto out;
 490         }
 491 #ifdef MAC
 492         error = mac_kld_check_load(td->td_ucred, nd.ni_vp);
 493         if (error) {
 494                 goto out;
 495         }
 496 #endif
 497
 498         /* Read the elf header from the file. */
 499         hdr = malloc(sizeof(*hdr), M_LINKER, M_WAITOK);
 500         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)hdr, sizeof(*hdr), 0,
 501             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 502             &resid, td);
 503         if (error)
 504                 goto out;
 505         if (resid != 0){
 506                 error = ENOEXEC;
 507                 goto out;
 508         }
 509
 510         if (!IS_ELF(*hdr)) {
 511                 error = ENOEXEC;
 512                 goto out;
 513         }
 514
 515         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
 516             || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
 517                 link_elf_error(filename, "Unsupported file layout");
 518                 error = ENOEXEC;
 519                 goto out;
 520         }
 521         if (hdr->e_ident[EI_VERSION] != EV_CURRENT
 522             || hdr->e_version != EV_CURRENT) {
 523                 link_elf_error(filename, "Unsupported file version");
 524                 error = ENOEXEC;
 525                 goto out;
 526         }
 527         if (hdr->e_type != ET_REL) {
 528                 error = ENOSYS;
 529                 goto out;
 530         }
 531         if (hdr->e_machine != ELF_TARG_MACH) {
 532                 link_elf_error(filename, "Unsupported machine");
 533                 error = ENOEXEC;
 534                 goto out;
 535         }
 536
 537         lf = linker_make_file(filename, &link_elf_class);
 538         if (!lf) {
 539                 error = ENOMEM;
 540                 goto out;
 541         }
 542         ef = (elf_file_t) lf;
 543         ef->nprogtab = 0;
 544         ef->e_shdr = 0;
 545         ef->nreltab = 0;
 546         ef->nrelatab = 0;
 547
 548         /* Allocate and read in the section header */
 549         nbytes = hdr->e_shnum * hdr->e_shentsize;
 550         if (nbytes == 0 || hdr->e_shoff == 0 ||
 551             hdr->e_shentsize != sizeof(Elf_Shdr)) {
 552                 error = ENOEXEC;
 553                 goto out;
 554         }
 555         shdr = malloc(nbytes, M_LINKER, M_WAITOK);
 556         ef->e_shdr = shdr;
 557         error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shdr, nbytes, hdr->e_shoff,
 558             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td);
 559         if (error)
 560                 goto out;
 561         if (resid) {
 562                 error = ENOEXEC;
 563                 goto out;
 564         }
 565
 566         /* Scan the section header for information and table sizing. */
 567         nsym = 0;
 568         symtabindex = -1;
 569         symstrindex = -1;
 570         for (i = 0; i < hdr->e_shnum; i++) {
 571                 if (shdr[i].sh_size == 0)
 572                         continue;
 573                 switch (shdr[i].sh_type) {
 574                 case SHT_PROGBITS:
 575                 case SHT_NOBITS:
 576                         ef->nprogtab++;
 577                         break;
 578                 case SHT_SYMTAB:
 579                         nsym++;
 580                         symtabindex = i;
 581                         symstrindex = shdr[i].sh_link;
 582                         break;
 583                 case SHT_REL:
 584                         ef->nreltab++;
 585                         break;
 586                 case SHT_RELA:
 587                         ef->nrelatab++;
 588                         break;
 589                 case SHT_STRTAB:
 590                         break;
 591                 }
 592         }
 593         if (ef->nprogtab == 0) {
 594                 link_elf_error(filename, "file has no contents");
 595                 error = ENOEXEC;
 596                 goto out;
 597         }
 598         if (nsym != 1) {
 599                 /* Only allow one symbol table for now */
 600                 link_elf_error(filename, "file has no valid symbol table");
 601                 error = ENOEXEC;
 602                 goto out;
 603         }
 604         if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
 605             shdr[symstrindex].sh_type != SHT_STRTAB) {
 606                 link_elf_error(filename, "file has invalid symbol strings");
 607                 error = ENOEXEC;
 608                 goto out;
 609         }
 610
 611         /* Allocate space for tracking the load chunks */
 612         if (ef->nprogtab != 0)
 613                 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab),
 614                     M_LINKER, M_WAITOK | M_ZERO);
 615         if (ef->nreltab != 0)
 616                 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab),
 617                     M_LINKER, M_WAITOK | M_ZERO);
 618         if (ef->nrelatab != 0)
 619                 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab),
 620                     M_LINKER, M_WAITOK | M_ZERO);
 621
 622         if (symtabindex == -1)
 623                 panic("lost symbol table index");
 624         /* Allocate space for and load the symbol table */
 625         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
 626         ef->ddbsymtab = malloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK);
 627         error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ef->ddbsymtab,
 628             shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
 629             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 630             &resid, td);
 631         if (error)
 632                 goto out;
 633         if (resid != 0){
 634                 error = EINVAL;
 635                 goto out;
 636         }
 637
 638         if (symstrindex == -1)
 639                 panic("lost symbol string index");
 640         /* Allocate space for and load the symbol strings */
 641         ef->ddbstrcnt = shdr[symstrindex].sh_size;
 642         ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
 643         error = vn_rdwr(UIO_READ, nd.ni_vp, ef->ddbstrtab,
 644             shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
 645             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 646             &resid, td);
 647         if (error)
 648                 goto out;
 649         if (resid != 0){
 650                 error = EINVAL;
 651                 goto out;
 652         }
 653
 654         /* Do we have a string table for the section names?  */
 655         shstrindex = -1;
 656         if (hdr->e_shstrndx != 0 &&
 657             shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
 658                 shstrindex = hdr->e_shstrndx;
 659                 ef->shstrcnt = shdr[shstrindex].sh_size;
 660                 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER,
 661                     M_WAITOK);
 662                 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->shstrtab,
 663                     shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
 664                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 665                     &resid, td);
 666                 if (error)
 667                         goto out;
 668                 if (resid != 0){
 669                         error = EINVAL;
 670                         goto out;
 671                 }
 672         }
 673
 674         /* Size up code/data(progbits) and bss(nobits). */
 675         alignmask = 0;
 676         for (i = 0; i < hdr->e_shnum; i++) {
 677                 if (shdr[i].sh_size == 0)
 678                         continue;
 679                 switch (shdr[i].sh_type) {
 680                 case SHT_PROGBITS:
 681                 case SHT_NOBITS:
 682                         alignmask = shdr[i].sh_addralign - 1;
 683                         mapsize += alignmask;
 684                         mapsize &= ~alignmask;
 685                         mapsize += shdr[i].sh_size;
 686                         break;
 687                 }
 688         }
 689
 690         /*
 691          * We know how much space we need for the text/data/bss/etc.
 692          * This stuff needs to be in a single chunk so that profiling etc
 693          * can get the bounds and gdb can associate offsets with modules
 694          */
 695         ef->object = vm_object_allocate(OBJT_DEFAULT,
 696             round_page(mapsize) >> PAGE_SHIFT);
 697         if (ef->object == NULL) {
 698                 error = ENOMEM;
 699                 goto out;
 700         }
 701         ef->address = (caddr_t) vm_map_min(kernel_map);
 702
 703         /*
 704          * In order to satisfy amd64's architectural requirements on the
 705          * location of code and data in the kernel's address space, request a
 706          * mapping that is above the kernel.
 707          */
 708 #ifdef __amd64__
 709         mapbase = KERNBASE;
 710 #else
 711         mapbase = VM_MIN_KERNEL_ADDRESS;
 712 #endif
 713         error = vm_map_find(kernel_map, ef->object, 0, &mapbase,
 714             round_page(mapsize), 0, VMFS_OPTIMAL_SPACE, VM_PROT_ALL,
 715             VM_PROT_ALL, 0);
 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 != NULL && shdr[i].sh_name != 0) {
 753                                 ef->progtab[pb].name =
 754                                     ef->shstrtab + shdr[i].sh_name;
 755                                 if (!strcmp(ef->progtab[pb].name, ".ctors")) {
 756                                         lf->ctors_addr = (caddr_t)mapbase;
 757                                         lf->ctors_size = shdr[i].sh_size;
 758                                 }
 759                         } else if (shdr[i].sh_type == SHT_PROGBITS)
 760                                 ef->progtab[pb].name = "<<PROGBITS>>";
 761                         else
 762                                 ef->progtab[pb].name = "<<NOBITS>>";
 763                         if (ef->progtab[pb].name != NULL &&
 764                             !strcmp(ef->progtab[pb].name, DPCPU_SETNAME))
 765                                 ef->progtab[pb].addr =
 766                                     dpcpu_alloc(shdr[i].sh_size);
 767 #ifdef VIMAGE
 768                         else if (ef->progtab[pb].name != NULL &&
 769                             !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 770                                 ef->progtab[pb].addr =
 771                                     vnet_data_alloc(shdr[i].sh_size);
 772 #endif
 773                         else
 774                                 ef->progtab[pb].addr =
 775                                     (void *)(uintptr_t)mapbase;
 776                         if (ef->progtab[pb].addr == NULL) {
 777                                 error = ENOSPC;
 778                                 goto out;
 779                         }
 780                         ef->progtab[pb].size = shdr[i].sh_size;
 781                         ef->progtab[pb].sec = i;
 782                         if (shdr[i].sh_type == SHT_PROGBITS) {
 783                                 error = vn_rdwr(UIO_READ, nd.ni_vp,
 784                                     ef->progtab[pb].addr,
 785                                     shdr[i].sh_size, shdr[i].sh_offset,
 786                                     UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
 787                                     NOCRED, &resid, td);
 788                                 if (error)
 789                                         goto out;
 790                                 if (resid != 0){
 791                                         error = EINVAL;
 792                                         goto out;
 793                                 }
 794                                 /* Initialize the per-cpu or vnet area. */
 795                                 if (ef->progtab[pb].addr != (void *)mapbase &&
 796                                     !strcmp(ef->progtab[pb].name, DPCPU_SETNAME))
 797                                         dpcpu_copy(ef->progtab[pb].addr,
 798                                             shdr[i].sh_size);
 799 #ifdef VIMAGE
 800                                 else if (ef->progtab[pb].addr !=
 801                                     (void *)mapbase &&
 802                                     !strcmp(ef->progtab[pb].name, VNET_SETNAME))
 803                                         vnet_data_copy(ef->progtab[pb].addr,
 804                                             shdr[i].sh_size);
 805 #endif
 806                         } else
 807                                 bzero(ef->progtab[pb].addr, shdr[i].sh_size);
 808
 809                         /* Update all symbol values with the offset. */
 810                         for (j = 0; j < ef->ddbsymcnt; j++) {
 811                                 es = &ef->ddbsymtab[j];
 812                                 if (es->st_shndx != i)
 813                                         continue;
 814                                 es->st_value += (Elf_Addr)ef->progtab[pb].addr;
 815                         }
 816                         mapbase += shdr[i].sh_size;
 817                         pb++;
 818                         break;
 819                 case SHT_REL:
 820                         ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER,
 821                             M_WAITOK);
 822                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
 823                         ef->reltab[rl].sec = shdr[i].sh_info;
 824                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 825                             (void *)ef->reltab[rl].rel,
 826                             shdr[i].sh_size, shdr[i].sh_offset,
 827                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 828                             &resid, td);
 829                         if (error)
 830                                 goto out;
 831                         if (resid != 0){
 832                                 error = EINVAL;
 833                                 goto out;
 834                         }
 835                         rl++;
 836                         break;
 837                 case SHT_RELA:
 838                         ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER,
 839                             M_WAITOK);
 840                         ef->relatab[ra].nrela =
 841                             shdr[i].sh_size / sizeof(Elf_Rela);
 842                         ef->relatab[ra].sec = shdr[i].sh_info;
 843                         error = vn_rdwr(UIO_READ, nd.ni_vp,
 844                             (void *)ef->relatab[ra].rela,
 845                             shdr[i].sh_size, shdr[i].sh_offset,
 846                             UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
 847                             &resid, td);
 848                         if (error)
 849                                 goto out;
 850                         if (resid != 0){
 851                                 error = EINVAL;
 852                                 goto out;
 853                         }
 854                         ra++;
 855                         break;
 856                 }
 857         }
 858         if (pb != ef->nprogtab)
 859                 panic("lost progbits");
 860         if (rl != ef->nreltab)
 861                 panic("lost reltab");
 862         if (ra != ef->nrelatab)
 863                 panic("lost relatab");
 864         if (mapbase != (vm_offset_t)ef->address + mapsize)
 865                 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
 866                     (u_long)mapbase, ef->address, (u_long)mapsize,
 867                     (u_long)(vm_offset_t)ef->address + mapsize);
 868
 869         /* Local intra-module relocations */
 870         link_elf_reloc_local(lf);
 871
 872         /* Pull in dependencies */
 873         VOP_UNLOCK(nd.ni_vp, 0);
 874         error = linker_load_dependencies(lf);
 875         vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
 876         if (error)
 877                 goto out;
 878
 879         /* External relocations */
 880         error = relocate_file(ef);
 881         if (error)
 882                 goto out;
 883
 884         /* Notify MD code that a module is being loaded. */
 885         error = elf_cpu_load_file(lf);
 886         if (error)
 887                 goto out;
 888
 889         /* Invoke .ctors */
 890         link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size);
 891
 892         *result = lf;
 893
 894 out:
 895         VOP_UNLOCK(nd.ni_vp, 0);
 896         vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
 897         if (error && lf)
 898                 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 899         if (hdr)
 900                 free(hdr, M_LINKER);
 901
 902         return error;
 903 }
 904
 905 static void
 906 link_elf_unload_file(linker_file_t file)
 907 {
 908         elf_file_t ef = (elf_file_t) file;
 909         int i;
 910
 911         /* Notify MD code that a module is being unloaded. */
 912         elf_cpu_unload_file(file);
 913
 914         if (ef->progtab) {
 915                 for (i = 0; i < ef->nprogtab; i++) {
 916                         if (ef->progtab[i].size == 0)
 917                                 continue;
 918                         if (ef->progtab[i].name == NULL)
 919                                 continue;
 920                         if (!strcmp(ef->progtab[i].name, DPCPU_SETNAME))
 921                                 dpcpu_free(ef->progtab[i].addr,
 922                                     ef->progtab[i].size);
 923 #ifdef VIMAGE
 924                         else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
 925                                 vnet_data_free(ef->progtab[i].addr,
 926                                     ef->progtab[i].size);
 927 #endif
 928                 }
 929         }
 930         if (ef->preloaded) {
 931                 if (ef->reltab)
 932                         free(ef->reltab, M_LINKER);
 933                 if (ef->relatab)
 934                         free(ef->relatab, M_LINKER);
 935                 if (ef->progtab)
 936                         free(ef->progtab, M_LINKER);
 937                 if (ef->ctftab)
 938                         free(ef->ctftab, M_LINKER);
 939                 if (ef->ctfoff)
 940                         free(ef->ctfoff, M_LINKER);
 941                 if (ef->typoff)
 942                         free(ef->typoff, M_LINKER);
 943                 if (file->filename != NULL)
 944                         preload_delete_name(file->filename);
 945                 /* XXX reclaim module memory? */
 946                 return;
 947         }
 948
 949         for (i = 0; i < ef->nreltab; i++)
 950                 if (ef->reltab[i].rel)
 951                         free(ef->reltab[i].rel, M_LINKER);
 952         for (i = 0; i < ef->nrelatab; i++)
 953                 if (ef->relatab[i].rela)
 954                         free(ef->relatab[i].rela, M_LINKER);
 955         if (ef->reltab)
 956                 free(ef->reltab, M_LINKER);
 957         if (ef->relatab)
 958                 free(ef->relatab, M_LINKER);
 959         if (ef->progtab)
 960                 free(ef->progtab, M_LINKER);
 961
 962         if (ef->object) {
 963                 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
 964                     (vm_offset_t) ef->address +
 965                     (ef->object->size << PAGE_SHIFT));
 966         }
 967         if (ef->e_shdr)
 968                 free(ef->e_shdr, M_LINKER);
 969         if (ef->ddbsymtab)
 970                 free(ef->ddbsymtab, M_LINKER);
 971         if (ef->ddbstrtab)
 972                 free(ef->ddbstrtab, M_LINKER);
 973         if (ef->shstrtab)
 974                 free(ef->shstrtab, M_LINKER);
 975         if (ef->ctftab)
 976                 free(ef->ctftab, M_LINKER);
 977         if (ef->ctfoff)
 978                 free(ef->ctfoff, M_LINKER);
 979         if (ef->typoff)
 980                 free(ef->typoff, M_LINKER);
 981 }
 982
 983 static const char *
 984 symbol_name(elf_file_t ef, Elf_Size r_info)
 985 {
 986         const Elf_Sym *ref;
 987
 988         if (ELF_R_SYM(r_info)) {
 989                 ref = ef->ddbsymtab + ELF_R_SYM(r_info);
 990                 return ef->ddbstrtab + ref->st_name;
 991         } else
 992                 return NULL;
 993 }
 994
 995 static Elf_Addr
 996 findbase(elf_file_t ef, int sec)
 997 {
 998         int i;
 999         Elf_Addr base = 0;
1000
1001         for (i = 0; i < ef->nprogtab; i++) {
1002                 if (sec == ef->progtab[i].sec) {
1003                         base = (Elf_Addr)ef->progtab[i].addr;
1004                         break;
1005                 }
1006         }
1007         return base;
1008 }
1009
1010 static int
1011 relocate_file(elf_file_t ef)
1012 {
1013         const Elf_Rel *rellim;
1014         const Elf_Rel *rel;
1015         const Elf_Rela *relalim;
1016         const Elf_Rela *rela;
1017         const char *symname;
1018         const Elf_Sym *sym;
1019         int i;
1020         Elf_Size symidx;
1021         Elf_Addr base;
1022
1023
1024         /* Perform relocations without addend if there are any: */
1025         for (i = 0; i < ef->nreltab; i++) {
1026                 rel = ef->reltab[i].rel;
1027                 if (rel == NULL)
1028                         panic("lost a reltab!");
1029                 rellim = rel + ef->reltab[i].nrel;
1030                 base = findbase(ef, ef->reltab[i].sec);
1031                 if (base == 0)
1032                         panic("lost base for reltab");
1033                 for ( ; rel < rellim; rel++) {
1034                         symidx = ELF_R_SYM(rel->r_info);
1035                         if (symidx >= ef->ddbsymcnt)
1036                                 continue;
1037                         sym = ef->ddbsymtab + symidx;
1038                         /* Local relocs are already done */
1039                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1040                                 continue;
1041                         if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL,
1042                             elf_obj_lookup)) {
1043                                 symname = symbol_name(ef, rel->r_info);
1044                                 printf("link_elf_obj: symbol %s undefined\n",
1045                                     symname);
1046                                 return ENOENT;
1047                         }
1048                 }
1049         }
1050
1051         /* Perform relocations with addend if there are any: */
1052         for (i = 0; i < ef->nrelatab; i++) {
1053                 rela = ef->relatab[i].rela;
1054                 if (rela == NULL)
1055                         panic("lost a relatab!");
1056                 relalim = rela + ef->relatab[i].nrela;
1057                 base = findbase(ef, ef->relatab[i].sec);
1058                 if (base == 0)
1059                         panic("lost base for relatab");
1060                 for ( ; rela < relalim; rela++) {
1061                         symidx = ELF_R_SYM(rela->r_info);
1062                         if (symidx >= ef->ddbsymcnt)
1063                                 continue;
1064                         sym = ef->ddbsymtab + symidx;
1065                         /* Local relocs are already done */
1066                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1067                                 continue;
1068                         if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA,
1069                             elf_obj_lookup)) {
1070                                 symname = symbol_name(ef, rela->r_info);
1071                                 printf("link_elf_obj: symbol %s undefined\n",
1072                                     symname);
1073                                 return ENOENT;
1074                         }
1075                 }
1076         }
1077
1078         return 0;
1079 }
1080
1081 static int
1082 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
1083 {
1084         elf_file_t ef = (elf_file_t) lf;
1085         const Elf_Sym *symp;
1086         const char *strp;
1087         int i;
1088
1089         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1090                 strp = ef->ddbstrtab + symp->st_name;
1091                 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
1092                         *sym = (c_linker_sym_t) symp;
1093                         return 0;
1094                 }
1095         }
1096         return ENOENT;
1097 }
1098
1099 static int
1100 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym,
1101     linker_symval_t *symval)
1102 {
1103         elf_file_t ef = (elf_file_t) lf;
1104         const Elf_Sym *es = (const Elf_Sym*) sym;
1105
1106         if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1107                 symval->name = ef->ddbstrtab + es->st_name;
1108                 symval->value = (caddr_t)es->st_value;
1109                 symval->size = es->st_size;
1110                 return 0;
1111         }
1112         return ENOENT;
1113 }
1114
1115 static int
1116 link_elf_search_symbol(linker_file_t lf, caddr_t value,
1117     c_linker_sym_t *sym, long *diffp)
1118 {
1119         elf_file_t ef = (elf_file_t) lf;
1120         u_long off = (uintptr_t) (void *) value;
1121         u_long diff = off;
1122         u_long st_value;
1123         const Elf_Sym *es;
1124         const Elf_Sym *best = 0;
1125         int i;
1126
1127         for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1128                 if (es->st_name == 0)
1129                         continue;
1130                 st_value = es->st_value;
1131                 if (off >= st_value) {
1132                         if (off - st_value < diff) {
1133                                 diff = off - st_value;
1134                                 best = es;
1135                                 if (diff == 0)
1136                                         break;
1137                         } else if (off - st_value == diff) {
1138                                 best = es;
1139                         }
1140                 }
1141         }
1142         if (best == 0)
1143                 *diffp = off;
1144         else
1145                 *diffp = diff;
1146         *sym = (c_linker_sym_t) best;
1147
1148         return 0;
1149 }
1150
1151 /*
1152  * Look up a linker set on an ELF system.
1153  */
1154 static int
1155 link_elf_lookup_set(linker_file_t lf, const char *name,
1156     void ***startp, void ***stopp, int *countp)
1157 {
1158         elf_file_t ef = (elf_file_t)lf;
1159         void **start, **stop;
1160         int i, count;
1161
1162         /* Relative to section number */
1163         for (i = 0; i < ef->nprogtab; i++) {
1164                 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
1165                     strcmp(ef->progtab[i].name + 4, name) == 0) {
1166                         start  = (void **)ef->progtab[i].addr;
1167                         stop = (void **)((char *)ef->progtab[i].addr +
1168                             ef->progtab[i].size);
1169                         count = stop - start;
1170                         if (startp)
1171                                 *startp = start;
1172                         if (stopp)
1173                                 *stopp = stop;
1174                         if (countp)
1175                                 *countp = count;
1176                         return (0);
1177                 }
1178         }
1179         return (ESRCH);
1180 }
1181
1182 static int
1183 link_elf_each_function_name(linker_file_t file,
1184     int (*callback)(const char *, void *), void *opaque)
1185 {
1186         elf_file_t ef = (elf_file_t)file;
1187         const Elf_Sym *symp;
1188         int i, error;
1189
1190         /* Exhaustive search */
1191         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1192                 if (symp->st_value != 0 &&
1193                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1194                         error = callback(ef->ddbstrtab + symp->st_name, opaque);
1195                         if (error)
1196                                 return (error);
1197                 }
1198         }
1199         return (0);
1200 }
1201
1202 static int
1203 link_elf_each_function_nameval(linker_file_t file,
1204     linker_function_nameval_callback_t callback, void *opaque)
1205 {
1206         linker_symval_t symval;
1207         elf_file_t ef = (elf_file_t)file;
1208         const Elf_Sym* symp;
1209         int i, error;
1210
1211         /* Exhaustive search */
1212         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1213                 if (symp->st_value != 0 &&
1214                     ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1215                         error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval);
1216                         if (error)
1217                                 return (error);
1218                         error = callback(file, i, &symval, opaque);
1219                         if (error)
1220                                 return (error);
1221                 }
1222         }
1223         return (0);
1224 }
1225
1226 /*
1227  * Symbol lookup function that can be used when the symbol index is known (ie
1228  * in relocations). It uses the symbol index instead of doing a fully fledged
1229  * hash table based lookup when such is valid. For example for local symbols.
1230  * This is not only more efficient, it's also more correct. It's not always
1231  * the case that the symbol can be found through the hash table.
1232  */
1233 static Elf_Addr
1234 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps)
1235 {
1236         elf_file_t ef = (elf_file_t)lf;
1237         const Elf_Sym *sym;
1238         const char *symbol;
1239         Elf_Addr ret;
1240
1241         /* Don't even try to lookup the symbol if the index is bogus. */
1242         if (symidx >= ef->ddbsymcnt)
1243                 return (0);
1244
1245         sym = ef->ddbsymtab + symidx;
1246
1247         /* Quick answer if there is a definition included. */
1248         if (sym->st_shndx != SHN_UNDEF)
1249                 return (sym->st_value);
1250
1251         /* If we get here, then it is undefined and needs a lookup. */
1252         switch (ELF_ST_BIND(sym->st_info)) {
1253         case STB_LOCAL:
1254                 /* Local, but undefined? huh? */
1255                 return (0);
1256
1257         case STB_GLOBAL:
1258                 /* Relative to Data or Function name */
1259                 symbol = ef->ddbstrtab + sym->st_name;
1260
1261                 /* Force a lookup failure if the symbol name is bogus. */
1262                 if (*symbol == 0)
1263                         return (0);
1264                 ret = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
1265                 return ret;
1266
1267         case STB_WEAK:
1268                 printf("link_elf_obj: Weak symbols not supported\n");
1269                 return (0);
1270
1271         default:
1272                 return (0);
1273         }
1274 }
1275
1276 static void
1277 link_elf_fix_link_set(elf_file_t ef)
1278 {
1279         static const char startn[] = "__start_";
1280         static const char stopn[] = "__stop_";
1281         Elf_Sym *sym;
1282         const char *sym_name, *linkset_name;
1283         Elf_Addr startp, stopp;
1284         Elf_Size symidx;
1285         int start, i;
1286
1287         startp = stopp = 0;
1288         for (symidx = 1 /* zero entry is special */;
1289                 symidx < ef->ddbsymcnt; symidx++) {
1290                 sym = ef->ddbsymtab + symidx;
1291                 if (sym->st_shndx != SHN_UNDEF)
1292                         continue;
1293
1294                 sym_name = ef->ddbstrtab + sym->st_name;
1295                 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
1296                         start = 1;
1297                         linkset_name = sym_name + sizeof(startn) - 1;
1298                 }
1299                 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
1300                         start = 0;
1301                         linkset_name = sym_name + sizeof(stopn) - 1;
1302                 }
1303                 else
1304                         continue;
1305
1306                 for (i = 0; i < ef->nprogtab; i++) {
1307                         if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
1308                                 startp = (Elf_Addr)ef->progtab[i].addr;
1309                                 stopp = (Elf_Addr)(startp + ef->progtab[i].size);
1310                                 break;
1311                         }
1312                 }
1313                 if (i == ef->nprogtab)
1314                         continue;
1315
1316                 sym->st_value = start ? startp : stopp;
1317                 sym->st_shndx = i;
1318         }
1319 }
1320
1321 static void
1322 link_elf_reloc_local(linker_file_t lf)
1323 {
1324         elf_file_t ef = (elf_file_t)lf;
1325         const Elf_Rel *rellim;
1326         const Elf_Rel *rel;
1327         const Elf_Rela *relalim;
1328         const Elf_Rela *rela;
1329         const Elf_Sym *sym;
1330         Elf_Addr base;
1331         int i;
1332         Elf_Size symidx;
1333
1334         link_elf_fix_link_set(ef);
1335
1336         /* Perform relocations without addend if there are any: */
1337         for (i = 0; i < ef->nreltab; i++) {
1338                 rel = ef->reltab[i].rel;
1339                 if (rel == NULL)
1340                         panic("lost a reltab!");
1341                 rellim = rel + ef->reltab[i].nrel;
1342                 base = findbase(ef, ef->reltab[i].sec);
1343                 if (base == 0)
1344                         panic("lost base for reltab");
1345                 for ( ; rel < rellim; rel++) {
1346                         symidx = ELF_R_SYM(rel->r_info);
1347                         if (symidx >= ef->ddbsymcnt)
1348                                 continue;
1349                         sym = ef->ddbsymtab + symidx;
1350                         /* Only do local relocs */
1351                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1352                                 continue;
1353                         elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
1354                             elf_obj_lookup);
1355                 }
1356         }
1357
1358         /* Perform relocations with addend if there are any: */
1359         for (i = 0; i < ef->nrelatab; i++) {
1360                 rela = ef->relatab[i].rela;
1361                 if (rela == NULL)
1362                         panic("lost a relatab!");
1363                 relalim = rela + ef->relatab[i].nrela;
1364                 base = findbase(ef, ef->relatab[i].sec);
1365                 if (base == 0)
1366                         panic("lost base for relatab");
1367                 for ( ; rela < relalim; rela++) {
1368                         symidx = ELF_R_SYM(rela->r_info);
1369                         if (symidx >= ef->ddbsymcnt)
1370                                 continue;
1371                         sym = ef->ddbsymtab + symidx;
1372                         /* Only do local relocs */
1373                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1374                                 continue;
1375                         elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
1376                             elf_obj_lookup);
1377                 }
1378         }
1379 }
1380
1381 static long
1382 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
1383 {
1384     elf_file_t ef = (elf_file_t)lf;
1385
1386     *symtab = ef->ddbsymtab;
1387
1388     if (*symtab == NULL)
1389         return (0);
1390
1391     return (ef->ddbsymcnt);
1392 }
1393
1394 static long
1395 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
1396 {
1397     elf_file_t ef = (elf_file_t)lf;
1398
1399     *strtab = ef->ddbstrtab;
1400
1401     if (*strtab == NULL)
1402         return (0);
1403
1404     return (ef->ddbstrcnt);
1405 }