xref: /freebsd/stand/common/load_elf.c (revision f6a3b357e9be4c6423c85eff9a847163a0d307c8)
1 /*-
2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3  * Copyright (c) 1998 Peter Wemm <peter@freebsd.org>
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 <sys/param.h>
32 #include <sys/endian.h>
33 #include <sys/exec.h>
34 #include <sys/linker.h>
35 #include <sys/module.h>
36 #include <sys/stdint.h>
37 #include <string.h>
38 #include <machine/elf.h>
39 #include <stand.h>
40 #define FREEBSD_ELF
41 #include <sys/link_elf.h>
42 
43 #include "bootstrap.h"
44 
45 #define COPYOUT(s,d,l)	archsw.arch_copyout((vm_offset_t)(s), d, l)
46 
47 #if defined(__i386__) && __ELF_WORD_SIZE == 64
48 #undef ELF_TARG_CLASS
49 #undef ELF_TARG_MACH
50 #define ELF_TARG_CLASS  ELFCLASS64
51 #define ELF_TARG_MACH   EM_X86_64
52 #endif
53 
54 typedef struct elf_file {
55 	Elf_Phdr	*ph;
56 	Elf_Ehdr	*ehdr;
57 	Elf_Sym		*symtab;
58 	Elf_Hashelt	*hashtab;
59 	Elf_Hashelt	nbuckets;
60 	Elf_Hashelt	nchains;
61 	Elf_Hashelt	*buckets;
62 	Elf_Hashelt	*chains;
63 	Elf_Rel	*rel;
64 	size_t	relsz;
65 	Elf_Rela	*rela;
66 	size_t	relasz;
67 	char	*strtab;
68 	size_t	strsz;
69 	int		fd;
70 	caddr_t	firstpage;
71 	size_t	firstlen;
72 	int		kernel;
73 	uint64_t	off;
74 } *elf_file_t;
75 
76 static int __elfN(loadimage)(struct preloaded_file *mp, elf_file_t ef,
77     uint64_t loadaddr);
78 static int __elfN(lookup_symbol)(struct preloaded_file *mp, elf_file_t ef,
79     const char* name, Elf_Sym* sym);
80 static int __elfN(reloc_ptr)(struct preloaded_file *mp, elf_file_t ef,
81     Elf_Addr p, void *val, size_t len);
82 static int __elfN(parse_modmetadata)(struct preloaded_file *mp, elf_file_t ef,
83     Elf_Addr p_start, Elf_Addr p_end);
84 static symaddr_fn __elfN(symaddr);
85 static char	*fake_modname(const char *name);
86 
87 const char	*__elfN(kerneltype) = "elf kernel";
88 const char	*__elfN(moduletype) = "elf module";
89 
90 uint64_t	__elfN(relocation_offset) = 0;
91 
92 extern void elf_wrong_field_size(void);
93 #define CONVERT_FIELD(b, f, e)			\
94 	switch (sizeof((b)->f)) {		\
95 	case 2:					\
96 		(b)->f = e ## 16toh((b)->f);	\
97 		break;				\
98 	case 4:					\
99 		(b)->f = e ## 32toh((b)->f);	\
100 		break;				\
101 	case 8:					\
102 		(b)->f = e ## 64toh((b)->f);	\
103 		break;				\
104 	default:				\
105 		/* Force a link time error. */	\
106 		elf_wrong_field_size();		\
107 		break;				\
108 	}
109 
110 #define CONVERT_SWITCH(h, d, f)			\
111 	switch ((h)->e_ident[EI_DATA]) {	\
112 	case ELFDATA2MSB:			\
113 		f(d, be);			\
114 		break;				\
115 	case ELFDATA2LSB:			\
116 		f(d, le);			\
117 		break;				\
118 	default:				\
119 		return (EINVAL);		\
120 	}
121 
122 
123 static int elf_header_convert(Elf_Ehdr *ehdr)
124 {
125 	/*
126 	 * Fixup ELF header endianness.
127 	 *
128 	 * The Xhdr structure was loaded using block read call to optimize file
129 	 * accesses. It might happen, that the endianness of the system memory
130 	 * is different that endianness of the ELF header.  Swap fields here to
131 	 * guarantee that Xhdr always contain valid data regardless of
132 	 * architecture.
133 	 */
134 #define HEADER_FIELDS(b, e)			\
135 	CONVERT_FIELD(b, e_type, e);		\
136 	CONVERT_FIELD(b, e_machine, e);		\
137 	CONVERT_FIELD(b, e_version, e);		\
138 	CONVERT_FIELD(b, e_entry, e);		\
139 	CONVERT_FIELD(b, e_phoff, e);		\
140 	CONVERT_FIELD(b, e_shoff, e);		\
141 	CONVERT_FIELD(b, e_flags, e);		\
142 	CONVERT_FIELD(b, e_ehsize, e);		\
143 	CONVERT_FIELD(b, e_phentsize, e);	\
144 	CONVERT_FIELD(b, e_phnum, e);		\
145 	CONVERT_FIELD(b, e_shentsize, e);	\
146 	CONVERT_FIELD(b, e_shnum, e);		\
147 	CONVERT_FIELD(b, e_shstrndx, e)
148 
149 	CONVERT_SWITCH(ehdr, ehdr, HEADER_FIELDS);
150 
151 #undef HEADER_FIELDS
152 
153 	return (0);
154 }
155 
156 static int elf_program_header_convert(const Elf_Ehdr *ehdr, Elf_Phdr *phdr)
157 {
158 #define PROGRAM_HEADER_FIELDS(b, e)		\
159 	CONVERT_FIELD(b, p_type, e);		\
160 	CONVERT_FIELD(b, p_flags, e);		\
161 	CONVERT_FIELD(b, p_offset, e);		\
162 	CONVERT_FIELD(b, p_vaddr, e);		\
163 	CONVERT_FIELD(b, p_paddr, e);		\
164 	CONVERT_FIELD(b, p_filesz, e);		\
165 	CONVERT_FIELD(b, p_memsz, e);		\
166 	CONVERT_FIELD(b, p_align, e)
167 
168 	CONVERT_SWITCH(ehdr, phdr, PROGRAM_HEADER_FIELDS);
169 
170 #undef PROGRAM_HEADER_FIELDS
171 
172 	return (0);
173 }
174 
175 static int elf_section_header_convert(const Elf_Ehdr *ehdr, Elf_Shdr *shdr)
176 {
177 #define SECTION_HEADER_FIELDS(b, e)		\
178 	CONVERT_FIELD(b, sh_name, e);		\
179 	CONVERT_FIELD(b, sh_type, e);		\
180 	CONVERT_FIELD(b, sh_link, e);		\
181 	CONVERT_FIELD(b, sh_info, e);		\
182 	CONVERT_FIELD(b, sh_flags, e);		\
183 	CONVERT_FIELD(b, sh_addr, e);		\
184 	CONVERT_FIELD(b, sh_offset, e);		\
185 	CONVERT_FIELD(b, sh_size, e);		\
186 	CONVERT_FIELD(b, sh_addralign, e);	\
187 	CONVERT_FIELD(b, sh_entsize, e)
188 
189 	CONVERT_SWITCH(ehdr, shdr, SECTION_HEADER_FIELDS);
190 
191 #undef SECTION_HEADER_FIELDS
192 
193 	return (0);
194 }
195 #undef CONVERT_SWITCH
196 #undef CONVERT_FIELD
197 
198 static int
199 __elfN(load_elf_header)(char *filename, elf_file_t ef)
200 {
201 	ssize_t			 bytes_read;
202 	Elf_Ehdr		*ehdr;
203 	int			 err;
204 
205 	/*
206 	 * Open the image, read and validate the ELF header
207 	 */
208 	if (filename == NULL)	/* can't handle nameless */
209 		return (EFTYPE);
210 	if ((ef->fd = open(filename, O_RDONLY)) == -1)
211 		return (errno);
212 	ef->firstpage = malloc(PAGE_SIZE);
213 	if (ef->firstpage == NULL) {
214 		close(ef->fd);
215 		return (ENOMEM);
216 	}
217 	bytes_read = read(ef->fd, ef->firstpage, PAGE_SIZE);
218 	ef->firstlen = (size_t)bytes_read;
219 	if (bytes_read < 0 || ef->firstlen <= sizeof(Elf_Ehdr)) {
220 		err = EFTYPE; /* could be EIO, but may be small file */
221 		goto error;
222 	}
223 	ehdr = ef->ehdr = (Elf_Ehdr *)ef->firstpage;
224 
225 	/* Is it ELF? */
226 	if (!IS_ELF(*ehdr)) {
227 		err = EFTYPE;
228 		goto error;
229 	}
230 
231 	if (ehdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || /* Layout ? */
232 	    ehdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
233 	    ehdr->e_ident[EI_VERSION] != EV_CURRENT) /* Version ? */ {
234 		err = EFTYPE;
235 		goto error;
236 	}
237 
238 	err = elf_header_convert(ehdr);
239 	if (err)
240 		goto error;
241 
242 	if (ehdr->e_version != EV_CURRENT || ehdr->e_machine != ELF_TARG_MACH) {
243 		/* Machine ? */
244 		err = EFTYPE;
245 		goto error;
246 	}
247 
248 #ifdef LOADER_VERIEXEC
249 	if (verify_file(ef->fd, filename, bytes_read, VE_MUST) < 0) {
250 	    err = EAUTH;
251 	    goto error;
252 	}
253 #endif
254 	return (0);
255 
256 error:
257 	if (ef->firstpage != NULL) {
258 		free(ef->firstpage);
259 		ef->firstpage = NULL;
260 	}
261 	if (ef->fd != -1) {
262 		close(ef->fd);
263 		ef->fd = -1;
264 	}
265 	return (err);
266 }
267 
268 /*
269  * Attempt to load the file (file) as an ELF module.  It will be stored at
270  * (dest), and a pointer to a module structure describing the loaded object
271  * will be saved in (result).
272  */
273 int
274 __elfN(loadfile)(char *filename, uint64_t dest, struct preloaded_file **result)
275 {
276 	return (__elfN(loadfile_raw)(filename, dest, result, 0));
277 }
278 
279 int
280 __elfN(loadfile_raw)(char *filename, uint64_t dest,
281     struct preloaded_file **result, int multiboot)
282 {
283 	struct preloaded_file	*fp, *kfp;
284 	struct elf_file		ef;
285 	Elf_Ehdr		*ehdr;
286 	int			err;
287 
288 	fp = NULL;
289 	bzero(&ef, sizeof(struct elf_file));
290 	ef.fd = -1;
291 
292 	err = __elfN(load_elf_header)(filename, &ef);
293 	if (err != 0)
294 		return (err);
295 
296 	ehdr = ef.ehdr;
297 
298 	/*
299 	 * Check to see what sort of module we are.
300 	 */
301 	kfp = file_findfile(NULL, __elfN(kerneltype));
302 #ifdef __powerpc__
303 	/*
304 	 * Kernels can be ET_DYN, so just assume the first loaded object is the
305 	 * kernel. This assumption will be checked later.
306 	 */
307 	if (kfp == NULL)
308 		ef.kernel = 1;
309 #endif
310 	if (ef.kernel || ehdr->e_type == ET_EXEC) {
311 		/* Looks like a kernel */
312 		if (kfp != NULL) {
313 			printf("elf" __XSTRING(__ELF_WORD_SIZE)
314 			    "_loadfile: kernel already loaded\n");
315 			err = EPERM;
316 			goto oerr;
317 		}
318 		/*
319 		 * Calculate destination address based on kernel entrypoint.
320 		 *
321 		 * For ARM, the destination address is independent of any values
322 		 * in the elf header (an ARM kernel can be loaded at any 2MB
323 		 * boundary), so we leave dest set to the value calculated by
324 		 * archsw.arch_loadaddr() and passed in to this function.
325 		 */
326 #ifndef __arm__
327 		if (ehdr->e_type == ET_EXEC)
328 			dest = (ehdr->e_entry & ~PAGE_MASK);
329 #endif
330 		if ((ehdr->e_entry & ~PAGE_MASK) == 0) {
331 			printf("elf" __XSTRING(__ELF_WORD_SIZE)
332 			    "_loadfile: not a kernel (maybe static binary?)\n");
333 			err = EPERM;
334 			goto oerr;
335 		}
336 		ef.kernel = 1;
337 
338 	} else if (ehdr->e_type == ET_DYN) {
339 		/* Looks like a kld module */
340 		if (multiboot != 0) {
341 			printf("elf" __XSTRING(__ELF_WORD_SIZE)
342 			    "_loadfile: can't load module as multiboot\n");
343 			err = EPERM;
344 			goto oerr;
345 		}
346 		if (kfp == NULL) {
347 			printf("elf" __XSTRING(__ELF_WORD_SIZE)
348 			    "_loadfile: can't load module before kernel\n");
349 			err = EPERM;
350 			goto oerr;
351 		}
352 		if (strcmp(__elfN(kerneltype), kfp->f_type)) {
353 			printf("elf" __XSTRING(__ELF_WORD_SIZE)
354 			 "_loadfile: can't load module with kernel type '%s'\n",
355 			    kfp->f_type);
356 			err = EPERM;
357 			goto oerr;
358 		}
359 		/* Looks OK, got ahead */
360 		ef.kernel = 0;
361 
362 	} else {
363 		err = EFTYPE;
364 		goto oerr;
365 	}
366 
367 	if (archsw.arch_loadaddr != NULL)
368 		dest = archsw.arch_loadaddr(LOAD_ELF, ehdr, dest);
369 	else
370 		dest = roundup(dest, PAGE_SIZE);
371 
372 	/*
373 	 * Ok, we think we should handle this.
374 	 */
375 	fp = file_alloc();
376 	if (fp == NULL) {
377 		printf("elf" __XSTRING(__ELF_WORD_SIZE)
378 		    "_loadfile: cannot allocate module info\n");
379 		err = EPERM;
380 		goto out;
381 	}
382 	if (ef.kernel == 1 && multiboot == 0)
383 		setenv("kernelname", filename, 1);
384 	fp->f_name = strdup(filename);
385 	if (multiboot == 0)
386 		fp->f_type = strdup(ef.kernel ?
387 		    __elfN(kerneltype) : __elfN(moduletype));
388 	else
389 		fp->f_type = strdup("elf multiboot kernel");
390 
391 #ifdef ELF_VERBOSE
392 	if (ef.kernel)
393 		printf("%s entry at 0x%jx\n", filename,
394 		    (uintmax_t)ehdr->e_entry);
395 #else
396 	printf("%s ", filename);
397 #endif
398 
399 	fp->f_size = __elfN(loadimage)(fp, &ef, dest);
400 	if (fp->f_size == 0 || fp->f_addr == 0)
401 		goto ioerr;
402 
403 	/* save exec header as metadata */
404 	file_addmetadata(fp, MODINFOMD_ELFHDR, sizeof(*ehdr), ehdr);
405 
406 	/* Load OK, return module pointer */
407 	*result = (struct preloaded_file *)fp;
408 	err = 0;
409 	goto out;
410 
411 ioerr:
412 	err = EIO;
413 oerr:
414 	file_discard(fp);
415 out:
416 	if (ef.firstpage)
417 		free(ef.firstpage);
418 	if (ef.fd != -1)
419 		close(ef.fd);
420 	return (err);
421 }
422 
423 /*
424  * With the file (fd) open on the image, and (ehdr) containing
425  * the Elf header, load the image at (off)
426  */
427 static int
428 __elfN(loadimage)(struct preloaded_file *fp, elf_file_t ef, uint64_t off)
429 {
430 	int		i;
431 	u_int		j;
432 	Elf_Ehdr	*ehdr;
433 	Elf_Phdr	*phdr, *php;
434 	Elf_Shdr	*shdr;
435 	char		*shstr;
436 	int		ret;
437 	vm_offset_t	firstaddr;
438 	vm_offset_t	lastaddr;
439 	size_t		chunk;
440 	ssize_t		result;
441 	Elf_Addr	ssym, esym;
442 	Elf_Dyn		*dp;
443 	Elf_Addr	adp;
444 	Elf_Addr	ctors;
445 	int		ndp;
446 	int		symstrindex;
447 	int		symtabindex;
448 	Elf_Size	size;
449 	u_int		fpcopy;
450 	Elf_Sym		sym;
451 	Elf_Addr	p_start, p_end;
452 
453 	dp = NULL;
454 	shdr = NULL;
455 	ret = 0;
456 	firstaddr = lastaddr = 0;
457 	ehdr = ef->ehdr;
458 	if (ehdr->e_type == ET_EXEC) {
459 #if defined(__i386__) || defined(__amd64__)
460 #if __ELF_WORD_SIZE == 64
461 		/* x86_64 relocates after locore */
462 		off = - (off & 0xffffffffff000000ull);
463 #else
464 		/* i386 relocates after locore */
465 		off = - (off & 0xff000000u);
466 #endif
467 #elif defined(__powerpc__)
468 		/*
469 		 * On the purely virtual memory machines like e500, the kernel
470 		 * is linked against its final VA range, which is most often
471 		 * not available at the loader stage, but only after kernel
472 		 * initializes and completes its VM settings. In such cases we
473 		 * cannot use p_vaddr field directly to load ELF segments, but
474 		 * put them at some 'load-time' locations.
475 		 */
476 		if (off & 0xf0000000u) {
477 			off = -(off & 0xf0000000u);
478 			/*
479 			 * XXX the physical load address should not be
480 			 * hardcoded. Note that the Book-E kernel assumes that
481 			 * it's loaded at a 16MB boundary for now...
482 			 */
483 			off += 0x01000000;
484 			ehdr->e_entry += off;
485 #ifdef ELF_VERBOSE
486 			printf("Converted entry 0x%jx\n", (uintmax_t)ehdr->e_entry);
487 #endif
488 		} else
489 			off = 0;
490 #elif defined(__arm__) && !defined(EFI)
491 		/*
492 		 * The elf headers in arm kernels specify virtual addresses in
493 		 * all header fields, even the ones that should be physical
494 		 * addresses.  We assume the entry point is in the first page,
495 		 * and masking the page offset will leave us with the virtual
496 		 * address the kernel was linked at.  We subtract that from the
497 		 * load offset, making 'off' into the value which, when added
498 		 * to a virtual address in an elf header, translates it to a
499 		 * physical address.  We do the va->pa conversion on the entry
500 		 * point address in the header now, so that later we can launch
501 		 * the kernel by just jumping to that address.
502 		 *
503 		 * When booting from UEFI the copyin and copyout functions
504 		 * handle adjusting the location relative to the first virtual
505 		 * address.  Because of this there is no need to adjust the
506 		 * offset or entry point address as these will both be handled
507 		 * by the efi code.
508 		 */
509 		off -= ehdr->e_entry & ~PAGE_MASK;
510 		ehdr->e_entry += off;
511 #ifdef ELF_VERBOSE
512 		printf("ehdr->e_entry 0x%jx, va<->pa off %llx\n",
513 		    (uintmax_t)ehdr->e_entry, off);
514 #endif
515 #else
516 		off = 0;	/* other archs use direct mapped kernels */
517 #endif
518 	}
519 	ef->off = off;
520 
521 	if (ef->kernel)
522 		__elfN(relocation_offset) = off;
523 
524 	if ((ehdr->e_phoff + ehdr->e_phnum * sizeof(*phdr)) > ef->firstlen) {
525 		printf("elf" __XSTRING(__ELF_WORD_SIZE)
526 		    "_loadimage: program header not within first page\n");
527 		goto out;
528 	}
529 	phdr = (Elf_Phdr *)(ef->firstpage + ehdr->e_phoff);
530 
531 	for (i = 0; i < ehdr->e_phnum; i++) {
532 		if (elf_program_header_convert(ehdr, phdr))
533 			continue;
534 
535 		/* We want to load PT_LOAD segments only.. */
536 		if (phdr[i].p_type != PT_LOAD)
537 			continue;
538 
539 #ifdef ELF_VERBOSE
540 		printf("Segment: 0x%lx@0x%lx -> 0x%lx-0x%lx",
541 		    (long)phdr[i].p_filesz, (long)phdr[i].p_offset,
542 		    (long)(phdr[i].p_vaddr + off),
543 		    (long)(phdr[i].p_vaddr + off + phdr[i].p_memsz - 1));
544 #else
545 		if ((phdr[i].p_flags & PF_W) == 0) {
546 			printf("text=0x%lx ", (long)phdr[i].p_filesz);
547 		} else {
548 			printf("data=0x%lx", (long)phdr[i].p_filesz);
549 			if (phdr[i].p_filesz < phdr[i].p_memsz)
550 				printf("+0x%lx", (long)(phdr[i].p_memsz -
551 				    phdr[i].p_filesz));
552 			printf(" ");
553 		}
554 #endif
555 		fpcopy = 0;
556 		if (ef->firstlen > phdr[i].p_offset) {
557 			fpcopy = ef->firstlen - phdr[i].p_offset;
558 			archsw.arch_copyin(ef->firstpage + phdr[i].p_offset,
559 			    phdr[i].p_vaddr + off, fpcopy);
560 		}
561 		if (phdr[i].p_filesz > fpcopy) {
562 			if (kern_pread(ef->fd, phdr[i].p_vaddr + off + fpcopy,
563 			    phdr[i].p_filesz - fpcopy,
564 			    phdr[i].p_offset + fpcopy) != 0) {
565 				printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
566 				    "_loadimage: read failed\n");
567 				goto out;
568 			}
569 		}
570 		/* clear space from oversized segments; eg: bss */
571 		if (phdr[i].p_filesz < phdr[i].p_memsz) {
572 #ifdef ELF_VERBOSE
573 			printf(" (bss: 0x%lx-0x%lx)",
574 			    (long)(phdr[i].p_vaddr + off + phdr[i].p_filesz),
575 			    (long)(phdr[i].p_vaddr + off + phdr[i].p_memsz -1));
576 #endif
577 
578 			kern_bzero(phdr[i].p_vaddr + off + phdr[i].p_filesz,
579 			    phdr[i].p_memsz - phdr[i].p_filesz);
580 		}
581 #ifdef ELF_VERBOSE
582 		printf("\n");
583 #endif
584 
585 		if (archsw.arch_loadseg != NULL)
586 			archsw.arch_loadseg(ehdr, phdr + i, off);
587 
588 		if (firstaddr == 0 || firstaddr > (phdr[i].p_vaddr + off))
589 			firstaddr = phdr[i].p_vaddr + off;
590 		if (lastaddr == 0 || lastaddr <
591 		    (phdr[i].p_vaddr + off + phdr[i].p_memsz))
592 			lastaddr = phdr[i].p_vaddr + off + phdr[i].p_memsz;
593 	}
594 	lastaddr = roundup(lastaddr, sizeof(long));
595 
596 	/*
597 	 * Get the section headers.  We need this for finding the .ctors
598 	 * section as well as for loading any symbols.  Both may be hard
599 	 * to do if reading from a .gz file as it involves seeking.  I
600 	 * think the rule is going to have to be that you must strip a
601 	 * file to remove symbols before gzipping it.
602 	 */
603 	chunk = (size_t)ehdr->e_shnum * (size_t)ehdr->e_shentsize;
604 	if (chunk == 0 || ehdr->e_shoff == 0)
605 		goto nosyms;
606 	shdr = alloc_pread(ef->fd, ehdr->e_shoff, chunk);
607 	if (shdr == NULL) {
608 		printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
609 		    "_loadimage: failed to read section headers");
610 		goto nosyms;
611 	}
612 
613 	for (i = 0; i < ehdr->e_shnum; i++)
614 		elf_section_header_convert(ehdr, &shdr[i]);
615 
616 	file_addmetadata(fp, MODINFOMD_SHDR, chunk, shdr);
617 
618 	/*
619 	 * Read the section string table and look for the .ctors section.
620 	 * We need to tell the kernel where it is so that it can call the
621 	 * ctors.
622 	 */
623 	chunk = shdr[ehdr->e_shstrndx].sh_size;
624 	if (chunk) {
625 		shstr = alloc_pread(ef->fd, shdr[ehdr->e_shstrndx].sh_offset,
626 		    chunk);
627 		if (shstr) {
628 			for (i = 0; i < ehdr->e_shnum; i++) {
629 				if (strcmp(shstr + shdr[i].sh_name,
630 				    ".ctors") != 0)
631 					continue;
632 				ctors = shdr[i].sh_addr;
633 				file_addmetadata(fp, MODINFOMD_CTORS_ADDR,
634 				    sizeof(ctors), &ctors);
635 				size = shdr[i].sh_size;
636 				file_addmetadata(fp, MODINFOMD_CTORS_SIZE,
637 				    sizeof(size), &size);
638 				break;
639 			}
640 			free(shstr);
641 		}
642 	}
643 
644 	/*
645 	 * Now load any symbols.
646 	 */
647 	symtabindex = -1;
648 	symstrindex = -1;
649 	for (i = 0; i < ehdr->e_shnum; i++) {
650 		if (shdr[i].sh_type != SHT_SYMTAB)
651 			continue;
652 		for (j = 0; j < ehdr->e_phnum; j++) {
653 			if (phdr[j].p_type != PT_LOAD)
654 				continue;
655 			if (shdr[i].sh_offset >= phdr[j].p_offset &&
656 			    (shdr[i].sh_offset + shdr[i].sh_size <=
657 			    phdr[j].p_offset + phdr[j].p_filesz)) {
658 				shdr[i].sh_offset = 0;
659 				shdr[i].sh_size = 0;
660 				break;
661 			}
662 		}
663 		if (shdr[i].sh_offset == 0 || shdr[i].sh_size == 0)
664 			continue;	/* alread loaded in a PT_LOAD above */
665 		/* Save it for loading below */
666 		symtabindex = i;
667 		symstrindex = shdr[i].sh_link;
668 	}
669 	if (symtabindex < 0 || symstrindex < 0)
670 		goto nosyms;
671 
672 	/* Ok, committed to a load. */
673 #ifndef ELF_VERBOSE
674 	printf("syms=[");
675 #endif
676 	ssym = lastaddr;
677 	for (i = symtabindex; i >= 0; i = symstrindex) {
678 #ifdef ELF_VERBOSE
679 		char	*secname;
680 
681 		switch(shdr[i].sh_type) {
682 		case SHT_SYMTAB:		/* Symbol table */
683 			secname = "symtab";
684 			break;
685 		case SHT_STRTAB:		/* String table */
686 			secname = "strtab";
687 			break;
688 		default:
689 			secname = "WHOA!!";
690 			break;
691 		}
692 #endif
693 		size = shdr[i].sh_size;
694 #if defined(__powerpc__)
695   #if __ELF_WORD_SIZE == 64
696 		size = htobe64(size);
697   #else
698 		size = htobe32(size);
699   #endif
700 #endif
701 
702 		archsw.arch_copyin(&size, lastaddr, sizeof(size));
703 		lastaddr += sizeof(size);
704 
705 #ifdef ELF_VERBOSE
706 		printf("\n%s: 0x%jx@0x%jx -> 0x%jx-0x%jx", secname,
707 		    (uintmax_t)shdr[i].sh_size, (uintmax_t)shdr[i].sh_offset,
708 		    (uintmax_t)lastaddr,
709 		    (uintmax_t)(lastaddr + shdr[i].sh_size));
710 #else
711 		if (i == symstrindex)
712 			printf("+");
713 		printf("0x%lx+0x%lx", (long)sizeof(size), (long)size);
714 #endif
715 
716 		if (lseek(ef->fd, (off_t)shdr[i].sh_offset, SEEK_SET) == -1) {
717 			printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
718 			   "_loadimage: could not seek for symbols - skipped!");
719 			lastaddr = ssym;
720 			ssym = 0;
721 			goto nosyms;
722 		}
723 		result = archsw.arch_readin(ef->fd, lastaddr, shdr[i].sh_size);
724 		if (result < 0 || (size_t)result != shdr[i].sh_size) {
725 			printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
726 			    "_loadimage: could not read symbols - skipped! "
727 			    "(%ju != %ju)", (uintmax_t)result,
728 			    (uintmax_t)shdr[i].sh_size);
729 			lastaddr = ssym;
730 			ssym = 0;
731 			goto nosyms;
732 		}
733 		/* Reset offsets relative to ssym */
734 		lastaddr += shdr[i].sh_size;
735 		lastaddr = roundup(lastaddr, sizeof(size));
736 		if (i == symtabindex)
737 			symtabindex = -1;
738 		else if (i == symstrindex)
739 			symstrindex = -1;
740 	}
741 	esym = lastaddr;
742 #ifndef ELF_VERBOSE
743 	printf("]");
744 #endif
745 
746 #if defined(__powerpc__)
747   /* On PowerPC we always need to provide BE data to the kernel */
748   #if __ELF_WORD_SIZE == 64
749 	ssym = htobe64((uint64_t)ssym);
750 	esym = htobe64((uint64_t)esym);
751   #else
752 	ssym = htobe32((uint32_t)ssym);
753 	esym = htobe32((uint32_t)esym);
754   #endif
755 #endif
756 
757 	file_addmetadata(fp, MODINFOMD_SSYM, sizeof(ssym), &ssym);
758 	file_addmetadata(fp, MODINFOMD_ESYM, sizeof(esym), &esym);
759 
760 nosyms:
761 	printf("\n");
762 
763 	ret = lastaddr - firstaddr;
764 	fp->f_addr = firstaddr;
765 
766 	php = NULL;
767 	for (i = 0; i < ehdr->e_phnum; i++) {
768 		if (phdr[i].p_type == PT_DYNAMIC) {
769 			php = phdr + i;
770 			adp = php->p_vaddr;
771 			file_addmetadata(fp, MODINFOMD_DYNAMIC, sizeof(adp),
772 			    &adp);
773 			break;
774 		}
775 	}
776 
777 	if (php == NULL) /* this is bad, we cannot get to symbols or _DYNAMIC */
778 		goto out;
779 
780 	ndp = php->p_filesz / sizeof(Elf_Dyn);
781 	if (ndp == 0)
782 		goto out;
783 	dp = malloc(php->p_filesz);
784 	if (dp == NULL)
785 		goto out;
786 	archsw.arch_copyout(php->p_vaddr + off, dp, php->p_filesz);
787 
788 	ef->strsz = 0;
789 	for (i = 0; i < ndp; i++) {
790 		if (dp[i].d_tag == 0)
791 			break;
792 		switch (dp[i].d_tag) {
793 		case DT_HASH:
794 			ef->hashtab =
795 			    (Elf_Hashelt*)(uintptr_t)(dp[i].d_un.d_ptr + off);
796 			break;
797 		case DT_STRTAB:
798 			ef->strtab =
799 			    (char *)(uintptr_t)(dp[i].d_un.d_ptr + off);
800 			break;
801 		case DT_STRSZ:
802 			ef->strsz = dp[i].d_un.d_val;
803 			break;
804 		case DT_SYMTAB:
805 			ef->symtab =
806 			    (Elf_Sym *)(uintptr_t)(dp[i].d_un.d_ptr + off);
807 			break;
808 		case DT_REL:
809 			ef->rel =
810 			    (Elf_Rel *)(uintptr_t)(dp[i].d_un.d_ptr + off);
811 			break;
812 		case DT_RELSZ:
813 			ef->relsz = dp[i].d_un.d_val;
814 			break;
815 		case DT_RELA:
816 			ef->rela =
817 			    (Elf_Rela *)(uintptr_t)(dp[i].d_un.d_ptr + off);
818 			break;
819 		case DT_RELASZ:
820 			ef->relasz = dp[i].d_un.d_val;
821 			break;
822 		default:
823 			break;
824 		}
825 	}
826 	if (ef->hashtab == NULL || ef->symtab == NULL ||
827 	    ef->strtab == NULL || ef->strsz == 0)
828 		goto out;
829 	COPYOUT(ef->hashtab, &ef->nbuckets, sizeof(ef->nbuckets));
830 	COPYOUT(ef->hashtab + 1, &ef->nchains, sizeof(ef->nchains));
831 	ef->buckets = ef->hashtab + 2;
832 	ef->chains = ef->buckets + ef->nbuckets;
833 
834 	if (__elfN(lookup_symbol)(fp, ef, "__start_set_modmetadata_set",
835 	    &sym) != 0)
836 		return 0;
837 	p_start = sym.st_value + ef->off;
838 	if (__elfN(lookup_symbol)(fp, ef, "__stop_set_modmetadata_set",
839 	    &sym) != 0)
840 		return ENOENT;
841 	p_end = sym.st_value + ef->off;
842 
843 	if (__elfN(parse_modmetadata)(fp, ef, p_start, p_end) == 0)
844 		goto out;
845 
846 	if (ef->kernel)		/* kernel must not depend on anything */
847 		goto out;
848 
849 out:
850 	if (dp)
851 		free(dp);
852 	if (shdr)
853 		free(shdr);
854 	return ret;
855 }
856 
857 static char invalid_name[] = "bad";
858 
859 char *
860 fake_modname(const char *name)
861 {
862 	const char *sp, *ep;
863 	char *fp;
864 	size_t len;
865 
866 	sp = strrchr(name, '/');
867 	if (sp)
868 		sp++;
869 	else
870 		sp = name;
871 
872 	ep = strrchr(sp, '.');
873 	if (ep == NULL) {
874 		ep = sp + strlen(sp);
875 	}
876 	if (ep == sp) {
877 		sp = invalid_name;
878 		ep = invalid_name + sizeof(invalid_name) - 1;
879 	}
880 
881 	len = ep - sp;
882 	fp = malloc(len + 1);
883 	if (fp == NULL)
884 		return NULL;
885 	memcpy(fp, sp, len);
886 	fp[len] = '\0';
887 	return fp;
888 }
889 
890 #if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64
891 struct mod_metadata64 {
892 	int		md_version;	/* structure version MDTV_* */
893 	int		md_type;	/* type of entry MDT_* */
894 	uint64_t	md_data;	/* specific data */
895 	uint64_t	md_cval;	/* common string label */
896 };
897 #endif
898 #if defined(__amd64__) && __ELF_WORD_SIZE == 32
899 struct mod_metadata32 {
900 	int		md_version;	/* structure version MDTV_* */
901 	int		md_type;	/* type of entry MDT_* */
902 	uint32_t	md_data;	/* specific data */
903 	uint32_t	md_cval;	/* common string label */
904 };
905 #endif
906 
907 int
908 __elfN(load_modmetadata)(struct preloaded_file *fp, uint64_t dest)
909 {
910 	struct elf_file		 ef;
911 	int			 err, i, j;
912 	Elf_Shdr		*sh_meta, *shdr = NULL;
913 	Elf_Shdr		*sh_data[2];
914 	char			*shstrtab = NULL;
915 	size_t			 size;
916 	Elf_Addr		 p_start, p_end;
917 
918 	bzero(&ef, sizeof(struct elf_file));
919 	ef.fd = -1;
920 
921 	err = __elfN(load_elf_header)(fp->f_name, &ef);
922 	if (err != 0)
923 		goto out;
924 
925 	if (ef.kernel == 1 || ef.ehdr->e_type == ET_EXEC) {
926 		ef.kernel = 1;
927 	} else if (ef.ehdr->e_type != ET_DYN) {
928 		err = EFTYPE;
929 		goto out;
930 	}
931 
932 	size = (size_t)ef.ehdr->e_shnum * (size_t)ef.ehdr->e_shentsize;
933 	shdr = alloc_pread(ef.fd, ef.ehdr->e_shoff, size);
934 	if (shdr == NULL) {
935 		err = ENOMEM;
936 		goto out;
937 	}
938 
939 	/* Load shstrtab. */
940 	shstrtab = alloc_pread(ef.fd, shdr[ef.ehdr->e_shstrndx].sh_offset,
941 	    shdr[ef.ehdr->e_shstrndx].sh_size);
942 	if (shstrtab == NULL) {
943 		printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
944 		    "load_modmetadata: unable to load shstrtab\n");
945 		err = EFTYPE;
946 		goto out;
947 	}
948 
949 	/* Find set_modmetadata_set and data sections. */
950 	sh_data[0] = sh_data[1] = sh_meta = NULL;
951 	for (i = 0, j = 0; i < ef.ehdr->e_shnum; i++) {
952 		if (strcmp(&shstrtab[shdr[i].sh_name],
953 		    "set_modmetadata_set") == 0) {
954 			sh_meta = &shdr[i];
955 		}
956 		if ((strcmp(&shstrtab[shdr[i].sh_name], ".data") == 0) ||
957 		    (strcmp(&shstrtab[shdr[i].sh_name], ".rodata") == 0)) {
958 			sh_data[j++] = &shdr[i];
959 		}
960 	}
961 	if (sh_meta == NULL || sh_data[0] == NULL || sh_data[1] == NULL) {
962 		printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
963     "load_modmetadata: unable to find set_modmetadata_set or data sections\n");
964 		err = EFTYPE;
965 		goto out;
966 	}
967 
968 	/* Load set_modmetadata_set into memory */
969 	err = kern_pread(ef.fd, dest, sh_meta->sh_size, sh_meta->sh_offset);
970 	if (err != 0) {
971 		printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
972     "load_modmetadata: unable to load set_modmetadata_set: %d\n", err);
973 		goto out;
974 	}
975 	p_start = dest;
976 	p_end = dest + sh_meta->sh_size;
977 	dest += sh_meta->sh_size;
978 
979 	/* Load data sections into memory. */
980 	err = kern_pread(ef.fd, dest, sh_data[0]->sh_size,
981 	    sh_data[0]->sh_offset);
982 	if (err != 0) {
983 		printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
984 		    "load_modmetadata: unable to load data: %d\n", err);
985 		goto out;
986 	}
987 
988 	/*
989 	 * We have to increment the dest, so that the offset is the same into
990 	 * both the .rodata and .data sections.
991 	 */
992 	ef.off = -(sh_data[0]->sh_addr - dest);
993 	dest +=	(sh_data[1]->sh_addr - sh_data[0]->sh_addr);
994 
995 	err = kern_pread(ef.fd, dest, sh_data[1]->sh_size,
996 	    sh_data[1]->sh_offset);
997 	if (err != 0) {
998 		printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
999 		    "load_modmetadata: unable to load data: %d\n", err);
1000 		goto out;
1001 	}
1002 
1003 	err = __elfN(parse_modmetadata)(fp, &ef, p_start, p_end);
1004 	if (err != 0) {
1005 		printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
1006 		    "load_modmetadata: unable to parse metadata: %d\n", err);
1007 		goto out;
1008 	}
1009 
1010 out:
1011 	if (shstrtab != NULL)
1012 		free(shstrtab);
1013 	if (shdr != NULL)
1014 		free(shdr);
1015 	if (ef.firstpage != NULL)
1016 		free(ef.firstpage);
1017 	if (ef.fd != -1)
1018 		close(ef.fd);
1019 	return (err);
1020 }
1021 
1022 int
1023 __elfN(parse_modmetadata)(struct preloaded_file *fp, elf_file_t ef,
1024     Elf_Addr p_start, Elf_Addr p_end)
1025 {
1026 	struct mod_metadata md;
1027 #if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64
1028 	struct mod_metadata64 md64;
1029 #elif defined(__amd64__) && __ELF_WORD_SIZE == 32
1030 	struct mod_metadata32 md32;
1031 #endif
1032 	struct mod_depend *mdepend;
1033 	struct mod_version mver;
1034 	char *s;
1035 	int error, modcnt, minfolen;
1036 	Elf_Addr v, p;
1037 
1038 	modcnt = 0;
1039 	p = p_start;
1040 	while (p < p_end) {
1041 		COPYOUT(p, &v, sizeof(v));
1042 		error = __elfN(reloc_ptr)(fp, ef, p, &v, sizeof(v));
1043 		if (error == EOPNOTSUPP)
1044 			v += ef->off;
1045 		else if (error != 0)
1046 			return (error);
1047 #if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64
1048 		COPYOUT(v, &md64, sizeof(md64));
1049 		error = __elfN(reloc_ptr)(fp, ef, v, &md64, sizeof(md64));
1050 		if (error == EOPNOTSUPP) {
1051 			md64.md_cval += ef->off;
1052 			md64.md_data += ef->off;
1053 		} else if (error != 0)
1054 			return (error);
1055 		md.md_version = md64.md_version;
1056 		md.md_type = md64.md_type;
1057 		md.md_cval = (const char *)(uintptr_t)md64.md_cval;
1058 		md.md_data = (void *)(uintptr_t)md64.md_data;
1059 #elif defined(__amd64__) && __ELF_WORD_SIZE == 32
1060 		COPYOUT(v, &md32, sizeof(md32));
1061 		error = __elfN(reloc_ptr)(fp, ef, v, &md32, sizeof(md32));
1062 		if (error == EOPNOTSUPP) {
1063 			md32.md_cval += ef->off;
1064 			md32.md_data += ef->off;
1065 		} else if (error != 0)
1066 			return (error);
1067 		md.md_version = md32.md_version;
1068 		md.md_type = md32.md_type;
1069 		md.md_cval = (const char *)(uintptr_t)md32.md_cval;
1070 		md.md_data = (void *)(uintptr_t)md32.md_data;
1071 #else
1072 		COPYOUT(v, &md, sizeof(md));
1073 		error = __elfN(reloc_ptr)(fp, ef, v, &md, sizeof(md));
1074 		if (error == EOPNOTSUPP) {
1075 			md.md_cval += ef->off;
1076 			md.md_data = (void *)((uintptr_t)md.md_data +
1077 			    (uintptr_t)ef->off);
1078 		} else if (error != 0)
1079 			return (error);
1080 #endif
1081 		p += sizeof(Elf_Addr);
1082 		switch(md.md_type) {
1083 		case MDT_DEPEND:
1084 			if (ef->kernel) /* kernel must not depend on anything */
1085 				break;
1086 			s = strdupout((vm_offset_t)md.md_cval);
1087 			minfolen = sizeof(*mdepend) + strlen(s) + 1;
1088 			mdepend = malloc(minfolen);
1089 			if (mdepend == NULL)
1090 				return ENOMEM;
1091 			COPYOUT((vm_offset_t)md.md_data, mdepend,
1092 			    sizeof(*mdepend));
1093 			strcpy((char*)(mdepend + 1), s);
1094 			free(s);
1095 			file_addmetadata(fp, MODINFOMD_DEPLIST, minfolen,
1096 			    mdepend);
1097 			free(mdepend);
1098 			break;
1099 		case MDT_VERSION:
1100 			s = strdupout((vm_offset_t)md.md_cval);
1101 			COPYOUT((vm_offset_t)md.md_data, &mver, sizeof(mver));
1102 			file_addmodule(fp, s, mver.mv_version, NULL);
1103 			free(s);
1104 			modcnt++;
1105 			break;
1106 		}
1107 	}
1108 	if (modcnt == 0) {
1109 		s = fake_modname(fp->f_name);
1110 		file_addmodule(fp, s, 1, NULL);
1111 		free(s);
1112 	}
1113 	return 0;
1114 }
1115 
1116 static unsigned long
1117 elf_hash(const char *name)
1118 {
1119 	const unsigned char *p = (const unsigned char *) name;
1120 	unsigned long h = 0;
1121 	unsigned long g;
1122 
1123 	while (*p != '\0') {
1124 		h = (h << 4) + *p++;
1125 		if ((g = h & 0xf0000000) != 0)
1126 			h ^= g >> 24;
1127 		h &= ~g;
1128 	}
1129 	return h;
1130 }
1131 
1132 static const char __elfN(bad_symtable)[] = "elf" __XSTRING(__ELF_WORD_SIZE)
1133     "_lookup_symbol: corrupt symbol table\n";
1134 int
1135 __elfN(lookup_symbol)(struct preloaded_file *fp, elf_file_t ef,
1136     const char* name, Elf_Sym *symp)
1137 {
1138 	Elf_Hashelt symnum;
1139 	Elf_Sym sym;
1140 	char *strp;
1141 	unsigned long hash;
1142 
1143 	hash = elf_hash(name);
1144 	COPYOUT(&ef->buckets[hash % ef->nbuckets], &symnum, sizeof(symnum));
1145 
1146 	while (symnum != STN_UNDEF) {
1147 		if (symnum >= ef->nchains) {
1148 			printf(__elfN(bad_symtable));
1149 			return ENOENT;
1150 		}
1151 
1152 		COPYOUT(ef->symtab + symnum, &sym, sizeof(sym));
1153 		if (sym.st_name == 0) {
1154 			printf(__elfN(bad_symtable));
1155 			return ENOENT;
1156 		}
1157 
1158 		strp = strdupout((vm_offset_t)(ef->strtab + sym.st_name));
1159 		if (strcmp(name, strp) == 0) {
1160 			free(strp);
1161 			if (sym.st_shndx != SHN_UNDEF ||
1162 			    (sym.st_value != 0 &&
1163 			    ELF_ST_TYPE(sym.st_info) == STT_FUNC)) {
1164 				*symp = sym;
1165 				return 0;
1166 			}
1167 			return ENOENT;
1168 		}
1169 		free(strp);
1170 		COPYOUT(&ef->chains[symnum], &symnum, sizeof(symnum));
1171 	}
1172 	return ENOENT;
1173 }
1174 
1175 /*
1176  * Apply any intra-module relocations to the value. p is the load address
1177  * of the value and val/len is the value to be modified. This does NOT modify
1178  * the image in-place, because this is done by kern_linker later on.
1179  *
1180  * Returns EOPNOTSUPP if no relocation method is supplied.
1181  */
1182 static int
1183 __elfN(reloc_ptr)(struct preloaded_file *mp, elf_file_t ef,
1184     Elf_Addr p, void *val, size_t len)
1185 {
1186 	size_t n;
1187 	Elf_Rela a;
1188 	Elf_Rel r;
1189 	int error;
1190 
1191 	/*
1192 	 * The kernel is already relocated, but we still want to apply
1193 	 * offset adjustments.
1194 	 */
1195 	if (ef->kernel)
1196 		return (EOPNOTSUPP);
1197 
1198 	for (n = 0; n < ef->relsz / sizeof(r); n++) {
1199 		COPYOUT(ef->rel + n, &r, sizeof(r));
1200 
1201 		error = __elfN(reloc)(ef, __elfN(symaddr), &r, ELF_RELOC_REL,
1202 		    ef->off, p, val, len);
1203 		if (error != 0)
1204 			return (error);
1205 	}
1206 	for (n = 0; n < ef->relasz / sizeof(a); n++) {
1207 		COPYOUT(ef->rela + n, &a, sizeof(a));
1208 
1209 		error = __elfN(reloc)(ef, __elfN(symaddr), &a, ELF_RELOC_RELA,
1210 		    ef->off, p, val, len);
1211 		if (error != 0)
1212 			return (error);
1213 	}
1214 
1215 	return (0);
1216 }
1217 
1218 static Elf_Addr
1219 __elfN(symaddr)(struct elf_file *ef, Elf_Size symidx)
1220 {
1221 
1222 	/* Symbol lookup by index not required here. */
1223 	return (0);
1224 }
1225