exec_elf32.c revision 1.49
1/*	$NetBSD: exec_elf32.c,v 1.49 2000/06/06 18:26:34 soren Exp $	*/
2
3/*-
4 * Copyright (c) 1994 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the NetBSD
21 *	Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 *    contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39/*
40 * Copyright (c) 1996 Christopher G. Demetriou
41 * All rights reserved.
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 *    notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 *    notice, this list of conditions and the following disclaimer in the
50 *    documentation and/or other materials provided with the distribution.
51 * 3. The name of the author may not be used to endorse or promote products
52 *    derived from this software without specific prior written permission
53 *
54 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
55 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
56 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
57 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
58 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
59 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
60 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
61 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
62 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
63 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
64 */
65
66/* If not included by exec_elf64.c, ELFSIZE won't be defined. */
67#ifndef ELFSIZE
68#define	ELFSIZE		32
69#endif
70
71#include "opt_compat_linux.h"
72#include "opt_compat_ibcs2.h"
73#include "opt_compat_svr4.h"
74#include "opt_compat_freebsd.h"
75#include "opt_compat_netbsd32.h"
76#include "opt_syscall_debug.h"
77
78#include <sys/param.h>
79#include <sys/systm.h>
80#include <sys/kernel.h>
81#include <sys/proc.h>
82#include <sys/malloc.h>
83#include <sys/namei.h>
84#include <sys/vnode.h>
85#include <sys/exec.h>
86#include <sys/exec_elf.h>
87#include <sys/fcntl.h>
88#include <sys/syscall.h>
89#include <sys/signalvar.h>
90#include <sys/mount.h>
91#include <sys/stat.h>
92
93#include <sys/mman.h>
94#include <vm/vm.h>
95#include <vm/vm_param.h>
96#include <vm/vm_map.h>
97
98#include <machine/cpu.h>
99#include <machine/reg.h>
100
101#ifdef COMPAT_NETBSD32
102#include <compat/netbsd32/netbsd32_exec.h>
103#endif
104
105#ifdef COMPAT_LINUX
106#include <compat/linux/common/linux_exec.h>
107#endif
108
109#ifdef COMPAT_SVR4
110#include <compat/svr4/svr4_exec.h>
111#endif
112
113#ifdef COMPAT_IBCS2
114#include <compat/ibcs2/ibcs2_exec.h>
115#endif
116
117#ifdef COMPAT_FREEBSD
118#include <compat/freebsd/freebsd_exec.h>
119#endif
120
121int	ELFNAME(check_header) __P((Elf_Ehdr *, int));
122int	ELFNAME(load_file) __P((struct proc *, struct exec_package *, char *,
123	    struct exec_vmcmd_set *, u_long *, struct elf_args *, Elf_Addr *));
124void	ELFNAME(load_psection) __P((struct exec_vmcmd_set *, struct vnode *,
125	    Elf_Phdr *, Elf_Addr *, u_long *, int *));
126
127int ELFNAME2(netbsd,signature) __P((struct proc *, struct exec_package *,
128    Elf_Ehdr *));
129static int ELFNAME2(netbsd,probe) __P((struct proc *, struct exec_package *,
130    Elf_Ehdr *, char *, Elf_Addr *));
131
132extern char sigcode[], esigcode[];
133#ifdef SYSCALL_DEBUG
134extern char *syscallnames[];
135#endif
136
137struct emul ELFNAMEEND(emul_netbsd) = {
138	"netbsd",
139	NULL,
140	sendsig,
141	SYS_syscall,
142	SYS_MAXSYSCALL,
143	sysent,
144#ifdef SYSCALL_DEBUG
145	syscallnames,
146#else
147	NULL,
148#endif
149	howmany(ELF_AUX_ENTRIES * sizeof(AuxInfo), sizeof (Elf_Addr)),
150	ELFNAME(copyargs),
151	setregs,
152	sigcode,
153	esigcode,
154};
155
156int (*ELFNAME(probe_funcs)[]) __P((struct proc *, struct exec_package *,
157    Elf_Ehdr *, char *, Elf_Addr *)) = {
158#if defined(COMPAT_NETBSD32) && (ELFSIZE == 32)
159	    /* This one should go first so it matches instead of netbsd */
160	ELFNAME2(netbsd32,probe),
161#endif
162	ELFNAME2(netbsd,probe),
163#if defined(COMPAT_FREEBSD) && (ELFSIZE == 32)
164	ELFNAME2(freebsd,probe),		/* XXX not 64-bit safe */
165#endif
166#if defined(COMPAT_LINUX)
167	ELFNAME2(linux,probe),
168#endif
169#if defined(COMPAT_SVR4) && (ELFSIZE == 32)
170	ELFNAME2(svr4,probe),			/* XXX not 64-bit safe */
171#endif
172#if defined(COMPAT_IBCS2) && (ELFSIZE == 32)
173	ELFNAME2(ibcs2,probe),			/* XXX not 64-bit safe */
174#endif
175};
176
177/* round up and down to page boundaries. */
178#define	ELF_ROUND(a, b)		(((a) + (b) - 1) & ~((b) - 1))
179#define	ELF_TRUNC(a, b)		((a) & ~((b) - 1))
180
181/*
182 * Copy arguments onto the stack in the normal way, but add some
183 * extra information in case of dynamic binding.
184 */
185void *
186ELFNAME(copyargs)(pack, arginfo, stack, argp)
187	struct exec_package *pack;
188	struct ps_strings *arginfo;
189	void *stack;
190	void *argp;
191{
192	size_t len;
193	AuxInfo ai[ELF_AUX_ENTRIES], *a;
194	struct elf_args *ap;
195
196	stack = copyargs(pack, arginfo, stack, argp);
197	if (!stack)
198		return NULL;
199
200	a = ai;
201
202	/*
203	 * Push extra arguments on the stack needed by dynamically
204	 * linked binaries
205	 */
206	if ((ap = (struct elf_args *)pack->ep_emul_arg)) {
207
208		a->a_type = AT_PHDR;
209		a->a_v = ap->arg_phaddr;
210		a++;
211
212		a->a_type = AT_PHENT;
213		a->a_v = ap->arg_phentsize;
214		a++;
215
216		a->a_type = AT_PHNUM;
217		a->a_v = ap->arg_phnum;
218		a++;
219
220		a->a_type = AT_PAGESZ;
221		a->a_v = NBPG;
222		a++;
223
224		a->a_type = AT_BASE;
225		a->a_v = ap->arg_interp;
226		a++;
227
228		a->a_type = AT_FLAGS;
229		a->a_v = 0;
230		a++;
231
232		a->a_type = AT_ENTRY;
233		a->a_v = ap->arg_entry;
234		a++;
235
236		free((char *)ap, M_TEMP);
237		pack->ep_emul_arg = NULL;
238	}
239
240	a->a_type = AT_NULL;
241	a->a_v = 0;
242	a++;
243
244	len = (a - ai) * sizeof(AuxInfo);
245	if (copyout(ai, stack, len))
246		return NULL;
247	stack = (caddr_t)stack + len;
248
249	return stack;
250}
251
252/*
253 * elf_check_header():
254 *
255 * Check header for validity; return 0 of ok ENOEXEC if error
256 */
257int
258ELFNAME(check_header)(eh, type)
259	Elf_Ehdr *eh;
260	int type;
261{
262
263	if (memcmp(eh->e_ident, ELFMAG, SELFMAG) != 0 ||
264	    eh->e_ident[EI_CLASS] != ELFCLASS)
265
266	switch (eh->e_machine) {
267
268	ELFDEFNNAME(MACHDEP_ID_CASES)
269
270	default:
271		return ENOEXEC;
272	}
273
274	if (eh->e_type != type)
275		return ENOEXEC;
276
277	return 0;
278}
279
280/*
281 * elf_load_psection():
282 *
283 * Load a psection at the appropriate address
284 */
285void
286ELFNAME(load_psection)(vcset, vp, ph, addr, size, prot)
287	struct exec_vmcmd_set *vcset;
288	struct vnode *vp;
289	Elf_Phdr *ph;
290	Elf_Addr *addr;
291	u_long *size;
292	int *prot;
293{
294	u_long uaddr, msize, psize, rm, rf;
295	long diff, offset;
296
297	/*
298	 * If the user specified an address, then we load there.
299	 */
300	if (*addr != ELFDEFNNAME(NO_ADDR)) {
301		if (ph->p_align > 1) {
302			*addr = ELF_ROUND(*addr, ph->p_align);
303			uaddr = ELF_TRUNC(ph->p_vaddr, ph->p_align);
304		} else
305			uaddr = ph->p_vaddr;
306		diff = ph->p_vaddr - uaddr;
307	} else {
308		*addr = uaddr = ph->p_vaddr;
309		if (ph->p_align > 1)
310			*addr = ELF_TRUNC(uaddr, ph->p_align);
311		diff = uaddr - *addr;
312	}
313
314	*prot |= (ph->p_flags & PF_R) ? VM_PROT_READ : 0;
315	*prot |= (ph->p_flags & PF_W) ? VM_PROT_WRITE : 0;
316	*prot |= (ph->p_flags & PF_X) ? VM_PROT_EXECUTE : 0;
317
318	offset = ph->p_offset - diff;
319	*size = ph->p_filesz + diff;
320	msize = ph->p_memsz + diff;
321	psize = round_page(*size);
322
323	if ((ph->p_flags & PF_W) != 0) {
324		/*
325		 * Because the pagedvn pager can't handle zero fill of the last
326		 * data page if it's not page aligned we map the last page
327		 * readvn.
328		 */
329		psize = trunc_page(*size);
330		NEW_VMCMD(vcset, vmcmd_map_pagedvn, psize, *addr, vp,
331		    offset, *prot);
332		if(psize != *size)
333			NEW_VMCMD(vcset, vmcmd_map_readvn, *size - psize,
334			    *addr + psize, vp, offset + psize, *prot);
335	} else
336		NEW_VMCMD(vcset, vmcmd_map_pagedvn, psize, *addr, vp,
337		    offset, *prot);
338
339	/*
340	 * Check if we need to extend the size of the segment
341	 */
342	rm = round_page(*addr + msize);
343	rf = round_page(*addr + *size);
344
345	if (rm != rf) {
346		NEW_VMCMD(vcset, vmcmd_map_zero, rm - rf, rf, NULLVP,
347		    0, *prot);
348		*size = msize;
349	}
350}
351
352/*
353 * elf_read_from():
354 *
355 *	Read from vnode into buffer at offset.
356 */
357int
358ELFNAME(read_from)(p, vp, off, buf, size)
359	struct vnode *vp;
360	u_long off;
361	struct proc *p;
362	caddr_t buf;
363	int size;
364{
365	int error;
366	size_t resid;
367
368	if ((error = vn_rdwr(UIO_READ, vp, buf, size, off, UIO_SYSSPACE,
369	    0, p->p_ucred, &resid, p)) != 0)
370		return error;
371	/*
372	 * See if we got all of it
373	 */
374	if (resid != 0)
375		return ENOEXEC;
376	return 0;
377}
378
379/*
380 * elf_load_file():
381 *
382 * Load a file (interpreter/library) pointed to by path
383 * [stolen from coff_load_shlib()]. Made slightly generic
384 * so it might be used externally.
385 */
386int
387ELFNAME(load_file)(p, epp, path, vcset, entry, ap, last)
388	struct proc *p;
389	struct exec_package *epp;
390	char *path;
391	struct exec_vmcmd_set *vcset;
392	u_long *entry;
393	struct elf_args	*ap;
394	Elf_Addr *last;
395{
396	int error, i;
397	struct nameidata nd;
398	struct vnode *vp;
399	struct vattr attr;
400	Elf_Ehdr eh;
401	Elf_Phdr *ph = NULL;
402	u_long phsize;
403	char *bp = NULL;
404	Elf_Addr addr = *last;
405
406	bp = path;
407	/*
408	 * 1. open file
409	 * 2. read filehdr
410	 * 3. map text, data, and bss out of it using VM_*
411	 */
412	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path, p);
413	if ((error = namei(&nd)) != 0)
414		return error;
415	vp = nd.ni_vp;
416
417	/*
418	 * Similarly, if it's not marked as executable, or it's not a regular
419	 * file, we don't allow it to be used.
420	 */
421	if (vp->v_type != VREG) {
422		error = EACCES;
423		goto badunlock;
424	}
425	if ((error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p)) != 0)
426		goto badunlock;
427
428	/* get attributes */
429	if ((error = VOP_GETATTR(vp, &attr, p->p_ucred, p)) != 0)
430		goto badunlock;
431
432	/*
433	 * Check mount point.  Though we're not trying to exec this binary,
434	 * we will be executing code from it, so if the mount point
435	 * disallows execution or set-id-ness, we punt or kill the set-id.
436	 */
437	if (vp->v_mount->mnt_flag & MNT_NOEXEC) {
438		error = EACCES;
439		goto badunlock;
440	}
441	if (vp->v_mount->mnt_flag & MNT_NOSUID)
442		epp->ep_vap->va_mode &= ~(S_ISUID | S_ISGID);
443
444#ifdef notyet /* XXX cgd 960926 */
445	XXX cgd 960926: (maybe) VOP_OPEN it (and VOP_CLOSE in copyargs?)
446#endif
447	VOP_UNLOCK(vp, 0);
448
449	if ((error = ELFNAME(read_from)(p, vp, 0, (caddr_t) &eh,
450	    sizeof(eh))) != 0)
451		goto bad;
452
453	if ((error = ELFNAME(check_header)(&eh, ET_DYN)) != 0)
454		goto bad;
455
456	phsize = eh.e_phnum * sizeof(Elf_Phdr);
457	ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
458
459	if ((error = ELFNAME(read_from)(p, vp, eh.e_phoff,
460	    (caddr_t) ph, phsize)) != 0)
461		goto bad;
462
463	/*
464	 * Load all the necessary sections
465	 */
466	for (i = 0; i < eh.e_phnum; i++) {
467		u_long size = 0;
468		int prot = 0;
469
470		switch (ph[i].p_type) {
471		case PT_LOAD:
472			ELFNAME(load_psection)(vcset, vp, &ph[i], &addr,
473			    &size, &prot);
474			/* If entry is within this section it must be text */
475			if (eh.e_entry >= ph[i].p_vaddr &&
476			    eh.e_entry < (ph[i].p_vaddr + size)) {
477				/* XXX */
478				*entry = addr + eh.e_entry;
479#ifdef mips
480				*entry -= ph[i].p_vaddr;
481#endif
482				ap->arg_interp = addr;
483			}
484			addr += size;
485			break;
486
487		case PT_DYNAMIC:
488		case PT_PHDR:
489		case PT_NOTE:
490			break;
491
492		default:
493			break;
494		}
495	}
496
497	free((char *)ph, M_TEMP);
498	*last = addr;
499	vrele(vp);
500	return 0;
501
502badunlock:
503	VOP_UNLOCK(vp, 0);
504
505bad:
506	if (ph != NULL)
507		free((char *)ph, M_TEMP);
508#ifdef notyet /* XXX cgd 960926 */
509	(maybe) VOP_CLOSE it
510#endif
511	vrele(vp);
512	return error;
513}
514
515/*
516 * exec_elf_makecmds(): Prepare an Elf binary's exec package
517 *
518 * First, set of the various offsets/lengths in the exec package.
519 *
520 * Then, mark the text image busy (so it can be demand paged) or error
521 * out if this is not possible.  Finally, set up vmcmds for the
522 * text, data, bss, and stack segments.
523 */
524int
525ELFNAME2(exec,makecmds)(p, epp)
526	struct proc *p;
527	struct exec_package *epp;
528{
529	Elf_Ehdr *eh = epp->ep_hdr;
530	Elf_Phdr *ph, *pp;
531	Elf_Addr phdr = 0, pos = 0;
532	int error, i, n, nload;
533	char interp[MAXPATHLEN];
534	u_long phsize;
535
536	if (epp->ep_hdrvalid < sizeof(Elf_Ehdr))
537		return ENOEXEC;
538
539	/*
540	 * XXX allow for executing shared objects. It seems silly
541	 * but other ELF-based systems allow it as well.
542	 */
543	if (ELFNAME(check_header)(eh, ET_EXEC) != 0 &&
544	    ELFNAME(check_header)(eh, ET_DYN) != 0)
545		return ENOEXEC;
546
547	/*
548	 * check if vnode is in open for writing, because we want to
549	 * demand-page out of it.  if it is, don't do it, for various
550	 * reasons
551	 */
552	if (epp->ep_vp->v_writecount != 0) {
553#ifdef DIAGNOSTIC
554		if (epp->ep_vp->v_flag & VTEXT)
555			panic("exec: a VTEXT vnode has writecount != 0\n");
556#endif
557		return ETXTBSY;
558	}
559	/*
560	 * Allocate space to hold all the program headers, and read them
561	 * from the file
562	 */
563	phsize = eh->e_phnum * sizeof(Elf_Phdr);
564	ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
565
566	if ((error = ELFNAME(read_from)(p, epp->ep_vp, eh->e_phoff,
567	    (caddr_t) ph, phsize)) != 0)
568		goto bad;
569
570	epp->ep_taddr = epp->ep_tsize = ELFDEFNNAME(NO_ADDR);
571	epp->ep_daddr = epp->ep_dsize = ELFDEFNNAME(NO_ADDR);
572
573	interp[0] = '\0';
574
575	for (i = 0; i < eh->e_phnum; i++) {
576		pp = &ph[i];
577		if (pp->p_type == PT_INTERP) {
578			if (pp->p_filesz >= sizeof(interp))
579				goto bad;
580			if ((error = ELFNAME(read_from)(p, epp->ep_vp,
581			    pp->p_offset, (caddr_t) interp,
582			    pp->p_filesz)) != 0)
583				goto bad;
584			break;
585		}
586	}
587
588	/*
589	 * Setup things for native emulation.
590	 */
591	epp->ep_emul = &ELFNAMEEND(emul_netbsd);
592	pos = ELFDEFNNAME(NO_ADDR);
593
594	/*
595	 * On the same architecture, we may be emulating different systems.
596	 * See which one will accept this executable. This currently only
597	 * applies to SVR4, and IBCS2 on the i386 and Linux on the i386
598	 * and the Alpha.
599	 *
600	 * Probe functions would normally see if the interpreter (if any)
601	 * exists. Emulation packages may possibly replace the interpreter in
602	 * interp[] with a changed path (/emul/xxx/<path>), and also
603	 * set the ep_emul field in the exec package structure.
604	 */
605	n = sizeof(ELFNAME(probe_funcs)) / sizeof(ELFNAME(probe_funcs)[0]);
606	if (n != 0) {
607		error = ENOEXEC;
608		for (i = 0; i < n && error; i++)
609			error = ELFNAME(probe_funcs)[i](p, epp, eh,
610			    interp, &pos);
611#ifdef notyet
612		/*
613		 * We should really use a signature in our native binaries
614		 * and have our own probe function for matching binaries,
615		 * before trying the emulations. For now, if the emulation
616		 * probes failed we default to native.
617		 */
618		if (error)
619			goto bad;
620#endif
621	}
622
623	/*
624	 * Load all the necessary sections
625	 */
626	for (i = nload = 0; i < eh->e_phnum; i++) {
627		Elf_Addr  addr = ELFDEFNNAME(NO_ADDR);
628		u_long size = 0;
629		int prot = 0;
630
631		pp = &ph[i];
632
633		switch (ph[i].p_type) {
634		case PT_LOAD:
635			/*
636			 * XXX
637			 * Can handle only 2 sections: text and data
638			 */
639			if (nload++ == 2)
640				goto bad;
641			ELFNAME(load_psection)(&epp->ep_vmcmds, epp->ep_vp,
642			    &ph[i], &addr, &size, &prot);
643
644			/*
645			 * Decide whether it's text or data by looking
646			 * at the entry point.
647			 */
648			if (eh->e_entry >= addr &&
649			    eh->e_entry < (addr + size)) {
650				epp->ep_taddr = addr;
651				epp->ep_tsize = size;
652				if (epp->ep_daddr == ELFDEFNNAME(NO_ADDR)) {
653					epp->ep_daddr = addr;
654					epp->ep_dsize = size;
655				}
656			} else {
657				epp->ep_daddr = addr;
658				epp->ep_dsize = size;
659			}
660			break;
661
662		case PT_SHLIB:
663#ifndef COMPAT_IBCS2			/* SCO has these sections */
664			error = ENOEXEC;
665			goto bad;
666#endif
667
668		case PT_INTERP:
669			/* Already did this one */
670		case PT_DYNAMIC:
671		case PT_NOTE:
672			break;
673
674		case PT_PHDR:
675			/* Note address of program headers (in text segment) */
676			phdr = pp->p_vaddr;
677			break;
678
679		default:
680			/*
681			 * Not fatal; we don't need to understand everything.
682			 */
683			break;
684		}
685	}
686
687	/* this breaks on, e.g., OpenBSD-compatible mips shared binaries. */
688#ifndef ELF_INTERP_NON_RELOCATABLE
689	/*
690	 * If no position to load the interpreter was set by a probe
691	 * function, pick the same address that a non-fixed mmap(0, ..)
692	 * would (i.e. something safely out of the way).
693	 */
694	if (pos == ELFDEFNNAME(NO_ADDR))
695		pos = round_page(epp->ep_daddr + MAXDSIZ);
696#endif	/* !ELF_INTERP_NON_RELOCATABLE */
697
698	/*
699	 * Check if we found a dynamically linked binary and arrange to load
700	 * it's interpreter
701	 */
702	if (interp[0]) {
703		struct elf_args *ap;
704
705		ap = (struct elf_args *)malloc(sizeof(struct elf_args),
706		    M_TEMP, M_WAITOK);
707		if ((error = ELFNAME(load_file)(p, epp, interp,
708		    &epp->ep_vmcmds, &epp->ep_entry, ap, &pos)) != 0) {
709			free((char *)ap, M_TEMP);
710			goto bad;
711		}
712		pos += phsize;
713		ap->arg_phaddr = phdr;
714
715		ap->arg_phentsize = eh->e_phentsize;
716		ap->arg_phnum = eh->e_phnum;
717		ap->arg_entry = eh->e_entry;
718
719		epp->ep_emul_arg = ap;
720	} else
721		epp->ep_entry = eh->e_entry;
722
723#ifdef ELF_MAP_PAGE_ZERO
724	/* Dell SVR4 maps page zero, yeuch! */
725	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, NBPG, 0, epp->ep_vp, 0,
726	    VM_PROT_READ);
727#endif
728	free((char *)ph, M_TEMP);
729	vn_marktext(epp->ep_vp);
730	return exec_elf_setup_stack(p, epp);
731
732bad:
733	free((char *)ph, M_TEMP);
734	kill_vmcmds(&epp->ep_vmcmds);
735	return ENOEXEC;
736}
737
738int
739ELFNAME2(netbsd,signature)(p, epp, eh)
740	struct proc *p;
741	struct exec_package *epp;
742	Elf_Ehdr *eh;
743{
744	Elf_Phdr *hph, *ph;
745	Elf_Nhdr *np = NULL;
746	size_t phsize;
747	int error;
748
749	phsize = eh->e_phnum * sizeof(Elf_Phdr);
750	hph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK);
751	if ((error = ELFNAME(read_from)(p, epp->ep_vp, eh->e_phoff,
752	    (caddr_t)hph, phsize)) != 0)
753		goto out1;
754
755	for (ph = hph;  ph < &hph[eh->e_phnum]; ph++) {
756		if (ph->p_type != PT_NOTE ||
757		    ph->p_filesz < sizeof(Elf_Nhdr) + ELF_NOTE_NETBSD_NAMESZ)
758			continue;
759
760		np = (Elf_Nhdr *)malloc(ph->p_filesz, M_TEMP, M_WAITOK);
761		if ((error = ELFNAME(read_from)(p, epp->ep_vp, ph->p_offset,
762		    (caddr_t)np, ph->p_filesz)) != 0)
763			goto out2;
764
765		if (np->n_type != ELF_NOTE_TYPE_OSVERSION) {
766			free(np, M_TEMP);
767			np = NULL;
768			continue;
769		}
770
771		/* Check the name and description sizes. */
772		if (np->n_namesz != ELF_NOTE_NETBSD_NAMESZ ||
773		    np->n_descsz != ELF_NOTE_NETBSD_DESCSZ)
774			goto out3;
775
776		/* Is the name "NetBSD\0\0"? */
777		if (memcmp((np + 1), ELF_NOTE_NETBSD_NAME,
778		    ELF_NOTE_NETBSD_NAMESZ))
779			goto out3;
780
781		/* XXX: We could check for the specific emulation here */
782		/* All checks succeeded. */
783		error = 0;
784		goto out2;
785	}
786
787out3:
788	error = ENOEXEC;
789out2:
790	if (np)
791		free(np, M_TEMP);
792out1:
793	free(hph, M_TEMP);
794	return error;
795}
796
797static int
798ELFNAME2(netbsd,probe)(p, epp, eh, itp, pos)
799	struct proc *p;
800	struct exec_package *epp;
801	Elf_Ehdr *eh;
802	char *itp;
803	Elf_Addr *pos;
804{
805	int error;
806
807	if ((error = ELFNAME2(netbsd,signature)(p, epp, eh)) != 0)
808		return error;
809	epp->ep_emul = &ELFNAMEEND(emul_netbsd);
810	*pos = ELFDEFNNAME(NO_ADDR);
811	return 0;
812}
813