dma(8): Upgrade to v0.7.
[dragonfly.git] / sys / kern / link_elf.c
CommitLineData
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MD
1/*-
2 * Copyright (c) 1998 Doug Rabson
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: src/sys/kern/link_elf.c,v 1.24 1999/12/24 15:33:36 bde Exp $
d5fc85d0 27 * $DragonFly: src/sys/kern/link_elf.c,v 1.29 2008/08/01 23:11:16 dillon Exp $
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MD
28 */
29
30#include <sys/param.h>
31#include <sys/kernel.h>
32#include <sys/systm.h>
33#include <sys/malloc.h>
34#include <sys/proc.h>
fad57d0e 35#include <sys/nlookup.h>
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MD
36#include <sys/fcntl.h>
37#include <sys/vnode.h>
38#include <sys/linker.h>
39#include <machine/elf.h>
40
41#include <vm/vm.h>
42#include <vm/vm_param.h>
43#include <vm/vm_zone.h>
44#include <sys/lock.h>
45#ifdef SPARSE_MAPPING
46#include <vm/vm_object.h>
47#include <vm/vm_kern.h>
48#include <vm/vm_extern.h>
49#endif
50#include <vm/pmap.h>
51#include <vm/vm_map.h>
52
dbdd9b9a
JG
53#if defined(__amd64__) && defined(_KERNEL_VIRTUAL)
54#include <stdio.h>
55#endif
56
1c0e3286
SS
57static int link_elf_preload_file(const char *, linker_file_t *);
58static int link_elf_preload_finish(linker_file_t);
59static int link_elf_load_file(const char*, linker_file_t*);
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MD
60static int link_elf_lookup_symbol(linker_file_t, const char*,
61 c_linker_sym_t*);
62static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, linker_symval_t*);
63static int link_elf_search_symbol(linker_file_t, caddr_t value,
64 c_linker_sym_t* sym, long* diffp);
65
66static void link_elf_unload_file(linker_file_t);
67static void link_elf_unload_module(linker_file_t);
dc62b251
MD
68static int link_elf_lookup_set(linker_file_t, const char *,
69 void ***, void ***, int *);
1c0e3286
SS
70static int elf_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *);
71static void link_elf_reloc_local(linker_file_t lf);
dc62b251 72
984263bc 73static struct linker_class_ops link_elf_class_ops = {
1c0e3286
SS
74 link_elf_load_file,
75 link_elf_preload_file,
984263bc
MD
76};
77
78static struct linker_file_ops link_elf_file_ops = {
1c0e3286
SS
79 .lookup_symbol = link_elf_lookup_symbol,
80 .symbol_values = link_elf_symbol_values,
81 .search_symbol = link_elf_search_symbol,
82 .unload = link_elf_unload_file,
83 .lookup_set = link_elf_lookup_set
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MD
84};
85
86static struct linker_file_ops link_elf_module_ops = {
1c0e3286
SS
87 .lookup_symbol = link_elf_lookup_symbol,
88 .symbol_values = link_elf_symbol_values,
89 .search_symbol = link_elf_search_symbol,
90 .preload_finish = link_elf_preload_finish,
91 .unload = link_elf_unload_module,
92 .lookup_set = link_elf_lookup_set,
984263bc 93};
761c7789 94
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95typedef struct elf_file {
96 caddr_t address; /* Relocation address */
97#ifdef SPARSE_MAPPING
98 vm_object_t object; /* VM object to hold file pages */
99#endif
100 const Elf_Dyn* dynamic; /* Symbol table etc. */
d5fc85d0
MD
101 Elf_Hashelt nbuckets; /* DT_HASH info */
102 Elf_Hashelt nchains;
103 const Elf_Hashelt* buckets;
104 const Elf_Hashelt* chains;
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MD
105 caddr_t hash;
106 caddr_t strtab; /* DT_STRTAB */
107 int strsz; /* DT_STRSZ */
108 const Elf_Sym* symtab; /* DT_SYMTAB */
109 Elf_Addr* got; /* DT_PLTGOT */
110 const Elf_Rel* pltrel; /* DT_JMPREL */
111 int pltrelsize; /* DT_PLTRELSZ */
112 const Elf_Rela* pltrela; /* DT_JMPREL */
113 int pltrelasize; /* DT_PLTRELSZ */
114 const Elf_Rel* rel; /* DT_REL */
115 int relsize; /* DT_RELSZ */
116 const Elf_Rela* rela; /* DT_RELA */
117 int relasize; /* DT_RELASZ */
118 caddr_t modptr;
119 const Elf_Sym* ddbsymtab; /* The symbol table we are using */
120 long ddbsymcnt; /* Number of symbols */
121 caddr_t ddbstrtab; /* String table */
122 long ddbstrcnt; /* number of bytes in string table */
123 caddr_t symbase; /* malloc'ed symbold base */
124 caddr_t strbase; /* malloc'ed string base */
125} *elf_file_t;
126
127static int parse_dynamic(linker_file_t lf);
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128static int relocate_file(linker_file_t lf);
129static int parse_module_symbols(linker_file_t lf);
130
131/*
132 * The kernel symbol table starts here.
133 */
134extern struct _dynamic _DYNAMIC;
135
136static void
137link_elf_init(void* arg)
138{
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139 Elf_Dyn *dp;
140 caddr_t modptr, baseptr, sizeptr;
141 elf_file_t ef;
142 char *modname;
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143
144#if ELF_TARG_CLASS == ELFCLASS32
145 linker_add_class("elf32", NULL, &link_elf_class_ops);
146#else
147 linker_add_class("elf64", NULL, &link_elf_class_ops);
148#endif
149
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MD
150 dp = (Elf_Dyn*) &_DYNAMIC;
151 if (dp) {
efda3bd0 152 ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_INTWAIT | M_ZERO);
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153 ef->address = 0;
154#ifdef SPARSE_MAPPING
155 ef->object = 0;
156#endif
157 ef->dynamic = dp;
158 modname = NULL;
159 modptr = preload_search_by_type("elf kernel");
160 if (modptr)
161 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
162 if (modname == NULL)
163 modname = "kernel";
164 linker_kernel_file = linker_make_file(modname, ef, &link_elf_file_ops);
165 if (linker_kernel_file == NULL)
166 panic("link_elf_init: Can't create linker structures for kernel");
167 parse_dynamic(linker_kernel_file);
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168#if defined(__amd64__) && defined(_KERNEL_VIRTUAL)
169 fprintf(stderr, "WARNING: KERNBASE being used\n");
170#endif
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171 linker_kernel_file->address = (caddr_t) KERNBASE;
172 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;
173
174 if (modptr) {
175 ef->modptr = modptr;
176 baseptr = preload_search_info(modptr, MODINFO_ADDR);
177 if (baseptr)
178 linker_kernel_file->address = *(caddr_t *)baseptr;
179 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
180 if (sizeptr)
181 linker_kernel_file->size = *(size_t *)sizeptr;
182 }
761c7789 183 parse_module_symbols(linker_kernel_file);
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184 linker_current_file = linker_kernel_file;
185 linker_kernel_file->flags |= LINKER_FILE_LINKED;
186 }
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187}
188
ba39e2e0 189SYSINIT(link_elf, SI_BOOT2_KLD, SI_ORDER_SECOND, link_elf_init, 0);
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190
191static int
192parse_module_symbols(linker_file_t lf)
193{
194 elf_file_t ef = lf->priv;
195 caddr_t pointer;
196 caddr_t ssym, esym, base;
197 caddr_t strtab;
198 int strcnt;
199 Elf_Sym* symtab;
200 int symcnt;
201
202 if (ef->modptr == NULL)
203 return 0;
204 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_SSYM);
205 if (pointer == NULL)
206 return 0;
207 ssym = *(caddr_t *)pointer;
208 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_ESYM);
209 if (pointer == NULL)
210 return 0;
211 esym = *(caddr_t *)pointer;
212
213 base = ssym;
214
215 symcnt = *(long *)base;
216 base += sizeof(long);
217 symtab = (Elf_Sym *)base;
218 base += roundup(symcnt, sizeof(long));
219
220 if (base > esym || base < ssym) {
6ea70f76 221 kprintf("Symbols are corrupt!\n");
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222 return EINVAL;
223 }
224
225 strcnt = *(long *)base;
226 base += sizeof(long);
227 strtab = base;
228 base += roundup(strcnt, sizeof(long));
229
230 if (base > esym || base < ssym) {
6ea70f76 231 kprintf("Symbols are corrupt!\n");
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232 return EINVAL;
233 }
234
235 ef->ddbsymtab = symtab;
236 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
237 ef->ddbstrtab = strtab;
238 ef->ddbstrcnt = strcnt;
239
240 return 0;
241}
242
243static int
244parse_dynamic(linker_file_t lf)
245{
246 elf_file_t ef = lf->priv;
247 const Elf_Dyn *dp;
248 int plttype = DT_REL;
249
250 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
251 switch (dp->d_tag) {
252 case DT_HASH:
253 {
254 /* From src/libexec/rtld-elf/rtld.c */
d5fc85d0 255 const Elf_Hashelt *hashtab = (const Elf_Hashelt *)
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256 (ef->address + dp->d_un.d_ptr);
257 ef->nbuckets = hashtab[0];
258 ef->nchains = hashtab[1];
259 ef->buckets = hashtab + 2;
260 ef->chains = ef->buckets + ef->nbuckets;
261 break;
262 }
263 case DT_STRTAB:
264 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr);
265 break;
266 case DT_STRSZ:
267 ef->strsz = dp->d_un.d_val;
268 break;
269 case DT_SYMTAB:
270 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr);
271 break;
272 case DT_SYMENT:
273 if (dp->d_un.d_val != sizeof(Elf_Sym))
274 return ENOEXEC;
275 break;
276 case DT_PLTGOT:
277 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr);
278 break;
279 case DT_REL:
280 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
281 break;
282 case DT_RELSZ:
283 ef->relsize = dp->d_un.d_val;
284 break;
285 case DT_RELENT:
286 if (dp->d_un.d_val != sizeof(Elf_Rel))
287 return ENOEXEC;
288 break;
289 case DT_JMPREL:
290 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
291 break;
292 case DT_PLTRELSZ:
293 ef->pltrelsize = dp->d_un.d_val;
294 break;
295 case DT_RELA:
296 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr);
297 break;
298 case DT_RELASZ:
299 ef->relasize = dp->d_un.d_val;
300 break;
301 case DT_RELAENT:
302 if (dp->d_un.d_val != sizeof(Elf_Rela))
303 return ENOEXEC;
304 break;
305 case DT_PLTREL:
306 plttype = dp->d_un.d_val;
307 if (plttype != DT_REL && plttype != DT_RELA)
308 return ENOEXEC;
309 break;
310 }
311 }
312
313 if (plttype == DT_RELA) {
314 ef->pltrela = (const Elf_Rela *) ef->pltrel;
315 ef->pltrel = NULL;
316 ef->pltrelasize = ef->pltrelsize;
317 ef->pltrelsize = 0;
318 }
319
320 ef->ddbsymtab = ef->symtab;
321 ef->ddbsymcnt = ef->nchains;
322 ef->ddbstrtab = ef->strtab;
323 ef->ddbstrcnt = ef->strsz;
324
325 return 0;
326}
327
328static void
329link_elf_error(const char *s)
330{
6ea70f76 331 kprintf("kldload: %s\n", s);
984263bc
MD
332}
333
334static int
1c0e3286 335link_elf_preload_file(const char *filename, linker_file_t *result)
984263bc
MD
336{
337 caddr_t modptr, baseptr, sizeptr, dynptr;
338 char *type;
339 elf_file_t ef;
340 linker_file_t lf;
341 int error;
342 vm_offset_t dp;
343
32832096
MD
344 /*
345 * Look to see if we have the module preloaded.
346 */
984263bc
MD
347 modptr = preload_search_by_name(filename);
348 if (modptr == NULL)
1c0e3286 349 return ENOENT;
984263bc
MD
350
351 /* It's preloaded, check we can handle it and collect information */
352 type = (char *)preload_search_info(modptr, MODINFO_TYPE);
353 baseptr = preload_search_info(modptr, MODINFO_ADDR);
354 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
355 dynptr = preload_search_info(modptr, MODINFO_METADATA|MODINFOMD_DYNAMIC);
1c0e3286
SS
356 if (type == NULL ||
357 (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " module") != 0 &&
358 strcmp(type, "elf module") != 0))
984263bc
MD
359 return (EFTYPE);
360 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL)
361 return (EINVAL);
362
efda3bd0 363 ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
984263bc
MD
364 ef->modptr = modptr;
365 ef->address = *(caddr_t *)baseptr;
366#ifdef SPARSE_MAPPING
367 ef->object = 0;
368#endif
369 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr;
370 ef->dynamic = (Elf_Dyn *)dp;
371 lf = linker_make_file(filename, ef, &link_elf_module_ops);
372 if (lf == NULL) {
efda3bd0 373 kfree(ef, M_LINKER);
984263bc
MD
374 return ENOMEM;
375 }
376 lf->address = ef->address;
377 lf->size = *(size_t *)sizeptr;
378
379 error = parse_dynamic(lf);
380 if (error) {
381 linker_file_unload(lf);
382 return error;
383 }
1c0e3286
SS
384 link_elf_reloc_local(lf);
385 *result = lf;
386 return (0);
387}
388
389static int
390link_elf_preload_finish(linker_file_t lf)
391{
392 int error;
393
984263bc 394 error = relocate_file(lf);
1c0e3286 395 if (error)
984263bc 396 return error;
761c7789 397 parse_module_symbols(lf);
1c0e3286 398
984263bc
MD
399 return (0);
400}
401
402static int
1c0e3286 403link_elf_load_file(const char* filename, linker_file_t* result)
984263bc 404{
fad57d0e 405 struct nlookupdata nd;
dadab5e9
MD
406 struct thread *td = curthread; /* XXX */
407 struct proc *p = td->td_proc;
fad57d0e 408 struct vnode *vp;
984263bc
MD
409 Elf_Ehdr *hdr;
410 caddr_t firstpage;
411 int nbytes, i;
412 Elf_Phdr *phdr;
413 Elf_Phdr *phlimit;
414 Elf_Phdr *segs[2];
415 int nsegs;
416 Elf_Phdr *phdyn;
417 Elf_Phdr *phphdr;
418 caddr_t mapbase;
419 size_t mapsize;
420 Elf_Off base_offset;
421 Elf_Addr base_vaddr;
422 Elf_Addr base_vlimit;
423 int error = 0;
424 int resid;
425 elf_file_t ef;
426 linker_file_t lf;
427 char *pathname;
428 Elf_Shdr *shdr;
429 int symtabindex;
430 int symstrindex;
431 int symcnt;
432 int strcnt;
433
6d6c8d9d
JT
434 /* XXX Hack for firmware loading where p == NULL */
435 if (p == NULL) {
436 p = &proc0;
437 }
438
dadab5e9 439 KKASSERT(p != NULL);
a3d82f10 440 if (p->p_ucred == NULL) {
6ea70f76 441 kprintf("link_elf_load_file: cannot load '%s' from filesystem"
a3d82f10
MD
442 " this early\n", filename);
443 return ENOENT;
444 }
984263bc
MD
445 shdr = NULL;
446 lf = NULL;
984263bc
MD
447 pathname = linker_search_path(filename);
448 if (pathname == NULL)
449 return ENOENT;
450
fad57d0e
MD
451 error = nlookup_init(&nd, pathname, UIO_SYSSPACE, NLC_FOLLOW|NLC_LOCKVP);
452 if (error == 0)
453 error = vn_open(&nd, NULL, FREAD, 0);
efda3bd0 454 kfree(pathname, M_LINKER);
fad57d0e
MD
455 if (error) {
456 nlookup_done(&nd);
984263bc 457 return error;
fad57d0e
MD
458 }
459 vp = nd.nl_open_vp;
460 nd.nl_open_vp = NULL;
461 nlookup_done(&nd);
984263bc
MD
462
463 /*
464 * Read the elf header from the file.
465 */
efda3bd0 466 firstpage = kmalloc(PAGE_SIZE, M_LINKER, M_WAITOK);
984263bc 467 hdr = (Elf_Ehdr *)firstpage;
fad57d0e 468 error = vn_rdwr(UIO_READ, vp, firstpage, PAGE_SIZE, 0,
87de5057 469 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
984263bc
MD
470 nbytes = PAGE_SIZE - resid;
471 if (error)
472 goto out;
473
474 if (!IS_ELF(*hdr)) {
475 error = ENOEXEC;
476 goto out;
477 }
478
479 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
480 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
481 link_elf_error("Unsupported file layout");
482 error = ENOEXEC;
483 goto out;
484 }
485 if (hdr->e_ident[EI_VERSION] != EV_CURRENT
486 || hdr->e_version != EV_CURRENT) {
487 link_elf_error("Unsupported file version");
488 error = ENOEXEC;
489 goto out;
490 }
491 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
1c0e3286 492 error = ENOSYS;
984263bc
MD
493 goto out;
494 }
495 if (hdr->e_machine != ELF_TARG_MACH) {
496 link_elf_error("Unsupported machine");
497 error = ENOEXEC;
498 goto out;
499 }
500
501 /*
502 * We rely on the program header being in the first page. This is
503 * not strictly required by the ABI specification, but it seems to
504 * always true in practice. And, it simplifies things considerably.
505 */
506 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
507 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
508 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
509 link_elf_error("Unreadable program headers");
510
511 /*
512 * Scan the program header entries, and save key information.
513 *
514 * We rely on there being exactly two load segments, text and data,
515 * in that order.
516 */
517 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
518 phlimit = phdr + hdr->e_phnum;
519 nsegs = 0;
520 phdyn = NULL;
521 phphdr = NULL;
522 while (phdr < phlimit) {
523 switch (phdr->p_type) {
524
525 case PT_LOAD:
526 if (nsegs == 2) {
527 link_elf_error("Too many sections");
528 error = ENOEXEC;
529 goto out;
530 }
531 segs[nsegs] = phdr;
532 ++nsegs;
533 break;
534
535 case PT_PHDR:
536 phphdr = phdr;
537 break;
538
539 case PT_DYNAMIC:
540 phdyn = phdr;
541 break;
1c0e3286
SS
542
543 case PT_INTERP:
544 error = ENOSYS;
545 goto out;
984263bc
MD
546 }
547
548 ++phdr;
549 }
550 if (phdyn == NULL) {
551 link_elf_error("Object is not dynamically-linked");
552 error = ENOEXEC;
553 goto out;
554 }
555
556 /*
557 * Allocate the entire address space of the object, to stake out our
558 * contiguous region, and to establish the base address for relocation.
559 */
560 base_offset = trunc_page(segs[0]->p_offset);
561 base_vaddr = trunc_page(segs[0]->p_vaddr);
562 base_vlimit = round_page(segs[1]->p_vaddr + segs[1]->p_memsz);
563 mapsize = base_vlimit - base_vaddr;
564
efda3bd0 565 ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
984263bc
MD
566#ifdef SPARSE_MAPPING
567 ef->object = vm_object_allocate(OBJT_DEFAULT, mapsize >> PAGE_SHIFT);
568 if (ef->object == NULL) {
efda3bd0 569 kfree(ef, M_LINKER);
984263bc
MD
570 error = ENOMEM;
571 goto out;
572 }
b12defdc
MD
573 vm_object_hold(ef->object);
574 vm_object_reference_locked(ef->object);
e4846942
MD
575 ef->address = (caddr_t)vm_map_min(&kernel_map);
576 error = vm_map_find(&kernel_map, ef->object, 0,
9388fcaa
MD
577 (vm_offset_t *)&ef->address,
578 mapsize, PAGE_SIZE,
579 1, VM_MAPTYPE_NORMAL,
1b874851
MD
580 VM_PROT_ALL, VM_PROT_ALL,
581 0);
b12defdc 582 vm_object_drop(ef->object);
984263bc
MD
583 if (error) {
584 vm_object_deallocate(ef->object);
efda3bd0 585 kfree(ef, M_LINKER);
984263bc
MD
586 goto out;
587 }
588#else
efda3bd0 589 ef->address = kmalloc(mapsize, M_LINKER, M_WAITOK);
984263bc
MD
590#endif
591 mapbase = ef->address;
592
593 /*
594 * Read the text and data sections and zero the bss.
595 */
596 for (i = 0; i < 2; i++) {
597 caddr_t segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
fad57d0e 598 error = vn_rdwr(UIO_READ, vp,
984263bc 599 segbase, segs[i]->p_filesz, segs[i]->p_offset,
87de5057 600 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
984263bc
MD
601 if (error) {
602#ifdef SPARSE_MAPPING
e4846942 603 vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
984263bc
MD
604 (vm_offset_t) ef->address
605 + (ef->object->size << PAGE_SHIFT));
606 vm_object_deallocate(ef->object);
607#else
efda3bd0 608 kfree(ef->address, M_LINKER);
984263bc 609#endif
efda3bd0 610 kfree(ef, M_LINKER);
984263bc
MD
611 goto out;
612 }
613 bzero(segbase + segs[i]->p_filesz,
614 segs[i]->p_memsz - segs[i]->p_filesz);
615
616#ifdef SPARSE_MAPPING
617 /*
618 * Wire down the pages
619 */
e4846942
MD
620 vm_map_wire(&kernel_map,
621 (vm_offset_t) segbase,
622 (vm_offset_t) segbase + segs[i]->p_memsz,
623 0);
984263bc
MD
624#endif
625 }
626
627 ef->dynamic = (const Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
628
629 lf = linker_make_file(filename, ef, &link_elf_file_ops);
630 if (lf == NULL) {
631#ifdef SPARSE_MAPPING
e4846942 632 vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
984263bc
MD
633 (vm_offset_t) ef->address
634 + (ef->object->size << PAGE_SHIFT));
635 vm_object_deallocate(ef->object);
636#else
efda3bd0 637 kfree(ef->address, M_LINKER);
984263bc 638#endif
efda3bd0 639 kfree(ef, M_LINKER);
984263bc
MD
640 error = ENOMEM;
641 goto out;
642 }
643 lf->address = ef->address;
644 lf->size = mapsize;
645
646 error = parse_dynamic(lf);
647 if (error)
648 goto out;
1c0e3286
SS
649 link_elf_reloc_local(lf);
650 error = linker_load_dependencies(lf);
984263bc
MD
651 if (error)
652 goto out;
653 error = relocate_file(lf);
654 if (error)
655 goto out;
656
657 /* Try and load the symbol table if it's present. (you can strip it!) */
658 nbytes = hdr->e_shnum * hdr->e_shentsize;
659 if (nbytes == 0 || hdr->e_shoff == 0)
660 goto nosyms;
efda3bd0 661 shdr = kmalloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
fad57d0e 662 error = vn_rdwr(UIO_READ, vp,
984263bc 663 (caddr_t)shdr, nbytes, hdr->e_shoff,
87de5057 664 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
984263bc
MD
665 if (error)
666 goto out;
667 symtabindex = -1;
668 symstrindex = -1;
669 for (i = 0; i < hdr->e_shnum; i++) {
670 if (shdr[i].sh_type == SHT_SYMTAB) {
671 symtabindex = i;
672 symstrindex = shdr[i].sh_link;
673 }
674 }
675 if (symtabindex < 0 || symstrindex < 0)
676 goto nosyms;
677
678 symcnt = shdr[symtabindex].sh_size;
efda3bd0 679 ef->symbase = kmalloc(symcnt, M_LINKER, M_WAITOK);
984263bc 680 strcnt = shdr[symstrindex].sh_size;
efda3bd0 681 ef->strbase = kmalloc(strcnt, M_LINKER, M_WAITOK);
fad57d0e 682 error = vn_rdwr(UIO_READ, vp,
984263bc 683 ef->symbase, symcnt, shdr[symtabindex].sh_offset,
87de5057 684 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
984263bc
MD
685 if (error)
686 goto out;
fad57d0e 687 error = vn_rdwr(UIO_READ, vp,
984263bc 688 ef->strbase, strcnt, shdr[symstrindex].sh_offset,
87de5057 689 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
984263bc
MD
690 if (error)
691 goto out;
692
693 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
694 ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
695 ef->ddbstrcnt = strcnt;
696 ef->ddbstrtab = ef->strbase;
697
984263bc
MD
698nosyms:
699
700 *result = lf;
701
702out:
703 if (error && lf)
704 linker_file_unload(lf);
705 if (shdr)
efda3bd0 706 kfree(shdr, M_LINKER);
984263bc 707 if (firstpage)
efda3bd0 708 kfree(firstpage, M_LINKER);
a11aaa81 709 vn_unlock(vp);
87de5057 710 vn_close(vp, FREAD);
984263bc
MD
711
712 return error;
713}
714
1c0e3286
SS
715Elf_Addr
716elf_relocaddr(linker_file_t lf, Elf_Addr x)
717{
718 elf_file_t ef;
719
720 ef = lf->priv;
721#if 0
722 if (x >= ef->pcpu_start && x < ef->pcpu_stop)
723 return ((x - ef->pcpu_start) + ef->pcpu_base);
724#ifdef VIMAGE
725 if (x >= ef->vnet_start && x < ef->vnet_stop)
726 return ((x - ef->vnet_start) + ef->vnet_base);
727#endif
728#endif
729 return (x);
730}
731
984263bc
MD
732static void
733link_elf_unload_file(linker_file_t file)
734{
735 elf_file_t ef = file->priv;
736
737 if (ef) {
738#ifdef SPARSE_MAPPING
739 if (ef->object) {
e4846942 740 vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
984263bc
MD
741 (vm_offset_t) ef->address
742 + (ef->object->size << PAGE_SHIFT));
743 vm_object_deallocate(ef->object);
744 }
745#else
746 if (ef->address)
efda3bd0 747 kfree(ef->address, M_LINKER);
984263bc
MD
748#endif
749 if (ef->symbase)
efda3bd0 750 kfree(ef->symbase, M_LINKER);
984263bc 751 if (ef->strbase)
efda3bd0
MD
752 kfree(ef->strbase, M_LINKER);
753 kfree(ef, M_LINKER);
984263bc
MD
754 }
755}
756
757static void
758link_elf_unload_module(linker_file_t file)
759{
760 elf_file_t ef = file->priv;
761
762 if (ef)
efda3bd0 763 kfree(ef, M_LINKER);
984263bc
MD
764 if (file->filename)
765 preload_delete_name(file->filename);
766}
767
984263bc 768static const char *
d5fc85d0 769symbol_name(elf_file_t ef, Elf_Size r_info)
984263bc
MD
770{
771 const Elf_Sym *ref;
772
773 if (ELF_R_SYM(r_info)) {
774 ref = ef->symtab + ELF_R_SYM(r_info);
775 return ef->strtab + ref->st_name;
776 } else
777 return NULL;
778}
779
780static int
781relocate_file(linker_file_t lf)
782{
783 elf_file_t ef = lf->priv;
784 const Elf_Rel *rellim;
785 const Elf_Rel *rel;
786 const Elf_Rela *relalim;
787 const Elf_Rela *rela;
788 const char *symname;
789
790 /* Perform relocations without addend if there are any: */
791 rel = ef->rel;
792 if (rel) {
793 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
794 while (rel < rellim) {
1c0e3286
SS
795 if (elf_reloc(lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL, elf_lookup)) {
796 symname = symbol_name(ef, rel->r_info);
6ea70f76 797 kprintf("link_elf: symbol %s undefined\n", symname);
984263bc
MD
798 return ENOENT;
799 }
800 rel++;
801 }
802 }
803
804 /* Perform relocations with addend if there are any: */
805 rela = ef->rela;
806 if (rela) {
807 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
808 while (rela < relalim) {
1c0e3286
SS
809 if (elf_reloc(lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA, elf_lookup)) {
810 symname = symbol_name(ef, rela->r_info);
6ea70f76 811 kprintf("link_elf: symbol %s undefined\n", symname);
984263bc
MD
812 return ENOENT;
813 }
814 rela++;
815 }
816 }
817
818 /* Perform PLT relocations without addend if there are any: */
819 rel = ef->pltrel;
820 if (rel) {
821 rellim = (const Elf_Rel *)((const char *)ef->pltrel + ef->pltrelsize);
822 while (rel < rellim) {
1c0e3286
SS
823 if (elf_reloc(lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL, elf_lookup)) {
824 symname = symbol_name(ef, rel->r_info);
6ea70f76 825 kprintf("link_elf: symbol %s undefined\n", symname);
984263bc
MD
826 return ENOENT;
827 }
828 rel++;
829 }
830 }
831
832 /* Perform relocations with addend if there are any: */
833 rela = ef->pltrela;
834 if (rela) {
835 relalim = (const Elf_Rela *)((const char *)ef->pltrela + ef->pltrelasize);
836 while (rela < relalim) {
837 symname = symbol_name(ef, rela->r_info);
1c0e3286 838 if (elf_reloc(lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA, elf_lookup)) {
6ea70f76 839 kprintf("link_elf: symbol %s undefined\n", symname);
984263bc
MD
840 return ENOENT;
841 }
842 rela++;
843 }
844 }
845
846 return 0;
847}
848
849/*
850 * Hash function for symbol table lookup. Don't even think about changing
851 * this. It is specified by the System V ABI.
852 */
853static unsigned long
854elf_hash(const char *name)
855{
856 const unsigned char *p = (const unsigned char *) name;
857 unsigned long h = 0;
858 unsigned long g;
859
860 while (*p != '\0') {
861 h = (h << 4) + *p++;
862 if ((g = h & 0xf0000000) != 0)
863 h ^= g >> 24;
864 h &= ~g;
865 }
866 return h;
867}
868
869int
870link_elf_lookup_symbol(linker_file_t lf, const char* name, c_linker_sym_t* sym)
871{
872 elf_file_t ef = lf->priv;
873 unsigned long symnum;
874 const Elf_Sym* symp;
875 const char *strp;
876 unsigned long hash;
877 int i;
878
1c0e3286
SS
879 /* If we don't have a hash, bail. */
880 if (ef->buckets == NULL || ef->nbuckets == 0) {
881 kprintf("link_elf_lookup_symbol: missing symbol hash table\n");
882 return ENOENT;
883 }
884
984263bc
MD
885 /* First, search hashed global symbols */
886 hash = elf_hash(name);
887 symnum = ef->buckets[hash % ef->nbuckets];
888
889 while (symnum != STN_UNDEF) {
890 if (symnum >= ef->nchains) {
6ea70f76 891 kprintf("link_elf_lookup_symbol: corrupt symbol table\n");
984263bc
MD
892 return ENOENT;
893 }
894
895 symp = ef->symtab + symnum;
896 if (symp->st_name == 0) {
6ea70f76 897 kprintf("link_elf_lookup_symbol: corrupt symbol table\n");
984263bc
MD
898 return ENOENT;
899 }
900
901 strp = ef->strtab + symp->st_name;
902
903 if (strcmp(name, strp) == 0) {
904 if (symp->st_shndx != SHN_UNDEF ||
905 (symp->st_value != 0 &&
d1786c1b
MD
906 ELF_ST_TYPE(symp->st_info) == STT_FUNC)
907 ) {
984263bc
MD
908 *sym = (c_linker_sym_t) symp;
909 return 0;
d1786c1b 910 } else {
984263bc 911 return ENOENT;
d1786c1b 912 }
984263bc
MD
913 }
914
915 symnum = ef->chains[symnum];
916 }
917
918 /* If we have not found it, look at the full table (if loaded) */
919 if (ef->symtab == ef->ddbsymtab)
920 return ENOENT;
921
922 /* Exhaustive search */
923 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
924 strp = ef->ddbstrtab + symp->st_name;
925 if (strcmp(name, strp) == 0) {
926 if (symp->st_shndx != SHN_UNDEF ||
927 (symp->st_value != 0 &&
928 ELF_ST_TYPE(symp->st_info) == STT_FUNC)) {
929 *sym = (c_linker_sym_t) symp;
930 return 0;
d1786c1b 931 } else {
984263bc 932 return ENOENT;
d1786c1b 933 }
984263bc
MD
934 }
935 }
984263bc
MD
936 return ENOENT;
937}
938
939static int
1c0e3286 940link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, linker_symval_t *symval)
984263bc 941{
1c0e3286
SS
942 elf_file_t ef = lf->priv;
943 const Elf_Sym *es = (const Elf_Sym *)sym;
944
945 if (es >= ef->symtab && ((es - ef->symtab) < ef->nchains)) {
946 symval->name = ef->strtab + es->st_name;
947 symval->value = (caddr_t) ef->address + es->st_value;
948 symval->size = es->st_size;
949 return 0;
950 }
951 if (ef->symtab == ef->ddbsymtab)
984263bc 952 return ENOENT;
1c0e3286
SS
953 if (es >= ef->ddbsymtab && ((es - ef->ddbsymtab) < ef->ddbsymcnt)) {
954 symval->name = ef->ddbstrtab + es->st_name;
955 symval->value = (caddr_t) ef->address + es->st_value;
956 symval->size = es->st_size;
957 return 0;
958 }
959 return ENOENT;
984263bc
MD
960}
961
962static int
963link_elf_search_symbol(linker_file_t lf, caddr_t value,
1c0e3286 964 c_linker_sym_t *sym, long *diffp)
984263bc 965{
1c0e3286
SS
966 elf_file_t ef = lf->priv;
967 u_long off = (uintptr_t)(void *)value;
968 u_long diff = off;
969 u_long st_value;
970 const Elf_Sym *es;
971 const Elf_Sym *best = 0;
972 int i;
973
974 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
975 if (es->st_name == 0)
976 continue;
977 st_value = es->st_value + (uintptr_t)(void *)ef->address;
978 if (off >= st_value) {
979 if (off - st_value < diff) {
980 diff = off - st_value;
981 best = es;
982 if (diff == 0)
983 break;
984 } else if (off - st_value == diff) {
985 best = es;
986 }
984263bc 987 }
1c0e3286
SS
988 }
989 if (best == 0)
990 *diffp = off;
991 else
992 *diffp = diff;
993 *sym = (c_linker_sym_t) best;
984263bc 994
1c0e3286 995 return 0;
984263bc 996}
dc62b251
MD
997
998/*
999 * Look up a linker set on an ELF system.
1000 */
1001static int
1002link_elf_lookup_set(linker_file_t lf, const char *name,
1c0e3286 1003 void ***startp, void ***stopp, int *countp)
dc62b251 1004{
1c0e3286
SS
1005 c_linker_sym_t sym;
1006 linker_symval_t symval;
1007 char *setsym;
1008 void **start, **stop;
1009 int len, error = 0, count;
1010
1011 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */
1012 setsym = kmalloc(len, M_LINKER, M_WAITOK);
1013
1014 /* get address of first entry */
1015 ksnprintf(setsym, len, "%s%s", "__start_set_", name);
1016 error = link_elf_lookup_symbol(lf, setsym, &sym);
1017 if (error)
1018 goto out;
1019 link_elf_symbol_values(lf, sym, &symval);
1020 if (symval.value == 0) {
1021 error = ESRCH;
1022 goto out;
1023 }
1024 start = (void **)symval.value;
1025
1026 /* get address of last entry */
1027 ksnprintf(setsym, len, "%s%s", "__stop_set_", name);
1028 error = link_elf_lookup_symbol(lf, setsym, &sym);
1029 if (error)
1030 goto out;
1031 link_elf_symbol_values(lf, sym, &symval);
1032 if (symval.value == 0) {
1033 error = ESRCH;
1034 goto out;
1035 }
1036 stop = (void **)symval.value;
dc62b251 1037
1c0e3286
SS
1038 /* and the number of entries */
1039 count = stop - start;
dc62b251 1040
1c0e3286
SS
1041 /* and copy out */
1042 if (startp)
1043 *startp = start;
1044 if (stopp)
1045 *stopp = stop;
1046 if (countp)
1047 *countp = count;
dc62b251 1048
1c0e3286
SS
1049out:
1050 kfree(setsym, M_LINKER);
1051 return error;
1052}
1053
1054/*
1055 * Symbol lookup function that can be used when the symbol index is known (ie
1056 * in relocations). It uses the symbol index instead of doing a fully fledged
1057 * hash table based lookup when such is valid. For example for local symbols.
1058 * This is not only more efficient, it's also more correct. It's not always
1059 * the case that the symbol can be found through the hash table.
1060 */
1061static int
1062elf_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *result)
1063{
1064 elf_file_t ef = lf->priv;
1065 const Elf_Sym *sym;
1066 const char *symbol;
1067
1068 /* Don't even try to lookup the symbol if the index is bogus. */
1069 if (symidx >= ef->nchains)
1070 return (ENOENT);
1071
1072 sym = ef->symtab + symidx;
1073
1074 /*
1075 * Don't do a full lookup when the symbol is local. It may even
1076 * fail because it may not be found through the hash table.
1077 */
1078 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
1079 /* Force lookup failure when we have an insanity. */
1080 if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0)
1081 return (ENOENT);
1082 return ((Elf_Addr) ef->address + sym->st_value);
1083 }
1084 /*
1085 * XXX we can avoid doing a hash table based lookup for global
1086 * symbols as well. This however is not always valid, so we'll
1087 * just do it the hard way for now. Performance tweaks can
1088 * always be added.
1089 */
1090
1091 symbol = ef->strtab + sym->st_name;
1092
1093 /* Force a lookup failure if the symbol name is bogus. */
1094 if (*symbol == 0)
1095 return (ENOENT);
1096
1097 return (linker_file_lookup_symbol(lf, symbol, deps, (caddr_t *)result));
dc62b251 1098}
1c0e3286
SS
1099static void
1100link_elf_reloc_local(linker_file_t lf)
1101{
1102 elf_file_t ef = lf->priv;
1103 const Elf_Rel *rellim;
1104 const Elf_Rel *rel;
1105 const Elf_Rela *relalim;
1106 const Elf_Rela *rela;
1107
1108 /* Perform relocations without addend if there are any: */
1109 if ((rel = ef->rel) != NULL) {
1110 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
1111 while (rel < rellim) {
1112 elf_reloc_local(lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL,
1113 elf_lookup);
1114 rel++;
1115 }
1116 }
dc62b251 1117
1c0e3286
SS
1118 /* Perform relocations with addend if there are any: */
1119 if ((rela = ef->rela) != NULL) {
1120 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
1121 while (rela < relalim) {
1122 elf_reloc_local(lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA,
1123 elf_lookup);
1124 rela++;
1125 }
1126 }
1127}