1/*	$NetBSD: core_elf32.c,v 1.35 2009/12/14 00:48:35 matt Exp $	*/
2
3/*
4 * Copyright (c) 2001 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed for the NetBSD Project by
20 *	Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 *    or promote products derived from this software without specific prior
23 *    written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38/*
39 * core_elf32.c/core_elf64.c: Support for the Elf32/Elf64 core file format.
40 */
41
42#include <sys/cdefs.h>
43__KERNEL_RCSID(1, "$NetBSD: core_elf32.c,v 1.35 2009/12/14 00:48:35 matt Exp $");
44
45#ifdef _KERNEL_OPT
46#include "opt_coredump.h"
47#endif
48
49#ifndef ELFSIZE
50#define	ELFSIZE		32
51#endif
52
53#include <sys/param.h>
54#include <sys/systm.h>
55#include <sys/proc.h>
56#include <sys/vnode.h>
57#include <sys/exec.h>
58#include <sys/exec_elf.h>
59#include <sys/ptrace.h>
60#include <sys/kmem.h>
61#include <sys/kauth.h>
62
63#include <machine/reg.h>
64
65#include <uvm/uvm_extern.h>
66
67#ifdef COREDUMP
68
69struct countsegs_state {
70	int	npsections;
71};
72
73static int	ELFNAMEEND(coredump_countsegs)(struct proc *, void *,
74		    struct uvm_coredump_state *);
75
76struct writesegs_state {
77	Elf_Phdr *psections;
78	off_t	secoff;
79};
80
81static int	ELFNAMEEND(coredump_writeseghdrs)(struct proc *, void *,
82		    struct uvm_coredump_state *);
83
84static int	ELFNAMEEND(coredump_notes)(struct proc *, struct lwp *, void *,
85		    size_t *);
86static int	ELFNAMEEND(coredump_note)(struct proc *, struct lwp *, void *,
87		    size_t *);
88
89#define	ELFROUNDSIZE	4	/* XXX Should it be sizeof(Elf_Word)? */
90#define	elfround(x)	roundup((x), ELFROUNDSIZE)
91
92#define elf_process_read_regs	CONCAT(process_read_regs, ELFSIZE)
93#ifdef __HAVE_PROCESS_XFPREGS
94#define elf_process_read_xfpregs CONCAT(process_read_xfpregs, ELFSIZE)
95#else
96#define elf_process_read_fpregs	CONCAT(process_read_fpregs, ELFSIZE)
97#endif
98#define elf_reg			CONCAT(process_reg, ELFSIZE)
99#define elf_fpreg		CONCAT(process_fpreg, ELFSIZE)
100
101int
102ELFNAMEEND(coredump)(struct lwp *l, void *cookie)
103{
104	struct proc *p;
105	Elf_Ehdr ehdr;
106	Elf_Phdr phdr, *psections;
107	size_t psectionssize;
108	struct countsegs_state cs;
109	struct writesegs_state ws;
110	off_t notestart, secstart, offset;
111	size_t notesize;
112	int error, i;
113
114	psections = NULL;
115	p = l->l_proc;
116	/*
117	 * We have to make a total of 3 passes across the map:
118	 *
119	 *	1. Count the number of map entries (the number of
120	 *	   PT_LOAD sections).
121	 *
122	 *	2. Write the P-section headers.
123	 *
124	 *	3. Write the P-sections.
125	 */
126
127	/* Pass 1: count the entries. */
128	cs.npsections = 0;
129	error = uvm_coredump_walkmap(p, NULL,
130	    ELFNAMEEND(coredump_countsegs), &cs);
131	if (error)
132		goto out;
133
134	/* Count the PT_NOTE section. */
135	cs.npsections++;
136
137	/* Get the size of the notes. */
138	error = ELFNAMEEND(coredump_notes)(p, l, NULL, &notesize);
139	if (error)
140		goto out;
141
142	memset(&ehdr.e_ident[EI_PAD], 0, sizeof(ehdr.e_ident) - EI_PAD);
143	memcpy(ehdr.e_ident, ELFMAG, SELFMAG);
144#if ELFSIZE == 32
145	ehdr.e_ident[EI_CLASS] = ELFCLASS32;
146#elif ELFSIZE == 64
147	ehdr.e_ident[EI_CLASS] = ELFCLASS64;
148#endif
149	ehdr.e_ident[EI_DATA] = ELFDEFNNAME(MACHDEP_ENDIANNESS);
150	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
151	/* XXX Should be the OSABI/ABI version of the executable. */
152	ehdr.e_ident[EI_OSABI] = ELFOSABI_SYSV;
153	ehdr.e_ident[EI_ABIVERSION] = 0;
154
155	ehdr.e_type = ET_CORE;
156	/* XXX This should be the e_machine of the executable. */
157	ehdr.e_machine = ELFDEFNNAME(MACHDEP_ID);
158	ehdr.e_version = EV_CURRENT;
159	ehdr.e_entry = 0;
160	ehdr.e_phoff = sizeof(ehdr);
161	ehdr.e_shoff = 0;
162	ehdr.e_flags = 0;
163	ehdr.e_ehsize = sizeof(ehdr);
164	ehdr.e_phentsize = sizeof(Elf_Phdr);
165	ehdr.e_phnum = cs.npsections;
166	ehdr.e_shentsize = 0;
167	ehdr.e_shnum = 0;
168	ehdr.e_shstrndx = 0;
169
170#ifdef ELF_MD_COREDUMP_SETUP
171	ELF_MD_COREDUMP_SETUP(l, &ehdr);
172#endif
173
174	/* Write out the ELF header. */
175	error = coredump_write(cookie, UIO_SYSSPACE, &ehdr, sizeof(ehdr));
176	if (error)
177		goto out;
178
179	offset = sizeof(ehdr);
180
181	notestart = offset + sizeof(phdr) * cs.npsections;
182	secstart = notestart + notesize;
183
184	psectionssize = cs.npsections * sizeof(Elf_Phdr);
185	psections = kmem_zalloc(psectionssize, KM_SLEEP);
186
187	/* Pass 2: now write the P-section headers. */
188	ws.secoff = secstart;
189	ws.psections = psections;
190	error = uvm_coredump_walkmap(p, cookie,
191	    ELFNAMEEND(coredump_writeseghdrs), &ws);
192	if (error)
193		goto out;
194
195	/* Write out the PT_NOTE header. */
196	ws.psections->p_type = PT_NOTE;
197	ws.psections->p_offset = notestart;
198	ws.psections->p_vaddr = 0;
199	ws.psections->p_paddr = 0;
200	ws.psections->p_filesz = notesize;
201	ws.psections->p_memsz = 0;
202	ws.psections->p_flags = PF_R;
203	ws.psections->p_align = ELFROUNDSIZE;
204
205	error = coredump_write(cookie, UIO_SYSSPACE, psections,
206	    cs.npsections * sizeof(Elf_Phdr));
207	if (error)
208		goto out;
209
210#ifdef DIAGNOSTIC
211	offset += cs.npsections * sizeof(Elf_Phdr);
212	if (offset != notestart)
213		panic("coredump: offset %lld != notestart %lld",
214		    (long long) offset, (long long) notestart);
215#endif
216
217	/* Write out the notes. */
218	error = ELFNAMEEND(coredump_notes)(p, l, cookie, &notesize);
219	if (error)
220		goto out;
221
222#ifdef DIAGNOSTIC
223	offset += notesize;
224	if (offset != secstart)
225		panic("coredump: offset %lld != secstart %lld",
226		    (long long) offset, (long long) secstart);
227#endif
228
229	/* Pass 3: finally, write the sections themselves. */
230	for (i = 0; i < cs.npsections - 1; i++) {
231		if (psections[i].p_filesz == 0)
232			continue;
233
234#ifdef DIAGNOSTIC
235		if (offset != psections[i].p_offset)
236			panic("coredump: offset %lld != p_offset[%d] %lld",
237			    (long long) offset, i,
238			    (long long) psections[i].p_filesz);
239#endif
240
241		error = coredump_write(cookie, UIO_USERSPACE,
242		    (void *)(vaddr_t)psections[i].p_vaddr,
243		    psections[i].p_filesz);
244		if (error)
245			goto out;
246
247#ifdef DIAGNOSTIC
248		offset += psections[i].p_filesz;
249#endif
250	}
251
252  out:
253	if (psections)
254		kmem_free(psections, psectionssize);
255	return (error);
256}
257
258static int
259ELFNAMEEND(coredump_countsegs)(struct proc *p, void *iocookie,
260    struct uvm_coredump_state *us)
261{
262	struct countsegs_state *cs = us->cookie;
263
264	cs->npsections++;
265	return (0);
266}
267
268static int
269ELFNAMEEND(coredump_writeseghdrs)(struct proc *p, void *iocookie,
270    struct uvm_coredump_state *us)
271{
272	struct writesegs_state *ws = us->cookie;
273	Elf_Phdr phdr;
274	vsize_t size, realsize;
275	vaddr_t end;
276	int error;
277
278	size = us->end - us->start;
279	realsize = us->realend - us->start;
280	end = us->realend;
281
282	while (realsize > 0) {
283		long buf[1024 / sizeof(long)];
284		size_t slen = realsize > sizeof(buf) ? sizeof(buf) : realsize;
285		const long *ep;
286		int i;
287
288		end -= slen;
289		if ((error = copyin_proc(p, (void *)end, buf, slen)) != 0)
290			return error;
291
292		ep = (const long *) &buf[slen / sizeof(buf[0])];
293		for (i = 0, ep--; buf <= ep; ep--, i++) {
294			if (*ep)
295				break;
296		}
297		realsize -= i * sizeof(buf[0]);
298		if (i * sizeof(buf[0]) < slen)
299			break;
300	}
301
302	phdr.p_type = PT_LOAD;
303	phdr.p_offset = ws->secoff;
304	phdr.p_vaddr = us->start;
305	phdr.p_paddr = 0;
306	phdr.p_filesz = realsize;
307	phdr.p_memsz = size;
308	phdr.p_flags = 0;
309	if (us->prot & VM_PROT_READ)
310		phdr.p_flags |= PF_R;
311	if (us->prot & VM_PROT_WRITE)
312		phdr.p_flags |= PF_W;
313	if (us->prot & VM_PROT_EXECUTE)
314		phdr.p_flags |= PF_X;
315	phdr.p_align = PAGE_SIZE;
316
317	ws->secoff += phdr.p_filesz;
318	*ws->psections++ = phdr;
319
320	return (0);
321}
322
323static int
324ELFNAMEEND(coredump_notes)(struct proc *p, struct lwp *l,
325    void *iocookie, size_t *sizep)
326{
327	struct netbsd_elfcore_procinfo cpi;
328	Elf_Nhdr nhdr;
329	size_t size, notesize;
330	int error;
331	struct lwp *l0;
332	sigset_t ss1, ss2;
333
334	size = 0;
335
336	/* First, write an elfcore_procinfo. */
337	notesize = sizeof(nhdr) + elfround(sizeof(ELF_NOTE_NETBSD_CORE_NAME)) +
338	    elfround(sizeof(cpi));
339	if (iocookie) {
340		cpi.cpi_version = NETBSD_ELFCORE_PROCINFO_VERSION;
341		cpi.cpi_cpisize = sizeof(cpi);
342		cpi.cpi_signo = p->p_sigctx.ps_signo;
343		cpi.cpi_sigcode = p->p_sigctx.ps_code;
344		cpi.cpi_siglwp = p->p_sigctx.ps_lwp;
345
346		/*
347		 * XXX This should be per-LWP.
348		 */
349		ss1 = p->p_sigpend.sp_set;
350		sigemptyset(&ss2);
351		LIST_FOREACH(l0, &p->p_lwps, l_sibling) {
352			sigplusset(&l0->l_sigpend.sp_set, &ss1);
353			sigplusset(&l0->l_sigmask, &ss2);
354		}
355		memcpy(&cpi.cpi_sigpend, &ss1, sizeof(cpi.cpi_sigpend));
356		memcpy(&cpi.cpi_sigmask, &ss2, sizeof(cpi.cpi_sigmask));
357		memcpy(&cpi.cpi_sigignore, &p->p_sigctx.ps_sigignore,
358		    sizeof(cpi.cpi_sigignore));
359		memcpy(&cpi.cpi_sigcatch, &p->p_sigctx.ps_sigcatch,
360		    sizeof(cpi.cpi_sigcatch));
361
362		cpi.cpi_pid = p->p_pid;
363		mutex_enter(proc_lock);
364		cpi.cpi_ppid = p->p_pptr->p_pid;
365		cpi.cpi_pgrp = p->p_pgid;
366		cpi.cpi_sid = p->p_session->s_sid;
367		mutex_exit(proc_lock);
368
369		cpi.cpi_ruid = kauth_cred_getuid(l->l_cred);
370		cpi.cpi_euid = kauth_cred_geteuid(l->l_cred);
371		cpi.cpi_svuid = kauth_cred_getsvuid(l->l_cred);
372
373		cpi.cpi_rgid = kauth_cred_getgid(l->l_cred);
374		cpi.cpi_egid = kauth_cred_getegid(l->l_cred);
375		cpi.cpi_svgid = kauth_cred_getsvgid(l->l_cred);
376
377		cpi.cpi_nlwps = p->p_nlwps;
378		(void)strncpy(cpi.cpi_name, p->p_comm, sizeof(cpi.cpi_name));
379		cpi.cpi_name[sizeof(cpi.cpi_name) - 1] = '\0';
380
381		nhdr.n_namesz = sizeof(ELF_NOTE_NETBSD_CORE_NAME);
382		nhdr.n_descsz = sizeof(cpi);
383		nhdr.n_type = ELF_NOTE_NETBSD_CORE_PROCINFO;
384
385		error = ELFNAMEEND(coredump_writenote)(p, iocookie, &nhdr,
386		    ELF_NOTE_NETBSD_CORE_NAME "\0\0\0", &cpi);
387		if (error)
388			return (error);
389	}
390
391	size += notesize;
392
393	/* XXX Add hook for machdep per-proc notes. */
394
395	/*
396	 * Now write the register info for the thread that caused the
397	 * coredump.
398	 */
399	error = ELFNAMEEND(coredump_note)(p, l, iocookie, &notesize);
400	if (error)
401		return (error);
402	size += notesize;
403
404	/*
405	 * Now, for each LWP, write the register info and any other
406	 * per-LWP notes.  Since we're dumping core, we don't bother
407	 * locking.
408	 */
409	LIST_FOREACH(l0, &p->p_lwps, l_sibling) {
410		if (l0 == l)		/* we've taken care of this thread */
411			continue;
412		error = ELFNAMEEND(coredump_note)(p, l0, iocookie, &notesize);
413		if (error)
414			return (error);
415		size += notesize;
416	}
417
418	*sizep = size;
419	return (0);
420}
421
422static int
423ELFNAMEEND(coredump_note)(struct proc *p, struct lwp *l, void *iocookie,
424    size_t *sizep)
425{
426	Elf_Nhdr nhdr;
427	int size, notesize, error;
428	int namesize;
429	char name[64+ELFROUNDSIZE];
430	elf_reg intreg;
431#ifdef PT_GETFPREGS
432	elf_fpreg freg;
433#endif
434
435	size = 0;
436
437	snprintf(name, sizeof(name)-ELFROUNDSIZE, "%s@%d",
438	    ELF_NOTE_NETBSD_CORE_NAME, l->l_lid);
439	namesize = strlen(name) + 1;
440	memset(name + namesize, 0, elfround(namesize) - namesize);
441
442	notesize = sizeof(nhdr) + elfround(namesize) + elfround(sizeof(intreg));
443	if (iocookie) {
444		error = elf_process_read_regs(l, &intreg);
445		if (error)
446			return (error);
447
448		nhdr.n_namesz = namesize;
449		nhdr.n_descsz = sizeof(intreg);
450		nhdr.n_type = PT_GETREGS;
451
452		error = ELFNAMEEND(coredump_writenote)(p, iocookie, &nhdr,
453		    name, &intreg);
454		if (error)
455			return (error);
456
457	}
458	size += notesize;
459
460#ifdef PT_GETFPREGS
461	notesize = sizeof(nhdr) + elfround(namesize) + elfround(sizeof(freg));
462	if (iocookie) {
463		size_t freglen = sizeof(freg);
464#ifdef __HAVE_PROCESS_XFPREGS
465		error = elf_process_read_xfpregs(l, &freg, &freglen);
466#else
467		error = elf_process_read_fpregs(l, &freg);
468#endif
469		if (error)
470			return (error);
471
472		nhdr.n_namesz = namesize;
473		nhdr.n_descsz = freglen;
474		nhdr.n_type = PT_GETFPREGS;
475
476		error = ELFNAMEEND(coredump_writenote)(p, iocookie, &nhdr,
477		    name, &freg);
478		if (error)
479			return (error);
480	}
481	size += notesize;
482#endif
483	*sizep = size;
484	/* XXX Add hook for machdep per-LWP notes. */
485	return (0);
486}
487
488int
489ELFNAMEEND(coredump_writenote)(struct proc *p, void *cookie, Elf_Nhdr *nhdr,
490    const char *name, void *data)
491{
492	int error;
493
494	error = coredump_write(cookie, UIO_SYSSPACE, nhdr, sizeof(*nhdr));
495	if (error)
496		return error;
497
498	error = coredump_write(cookie, UIO_SYSSPACE, name,
499	    elfround(nhdr->n_namesz));
500	if (error)
501		return error;
502
503	return coredump_write(cookie, UIO_SYSSPACE, data, nhdr->n_descsz);
504}
505
506#else	/* COREDUMP */
507
508int
509ELFNAMEEND(coredump)(struct lwp *l, void *cookie)
510{
511
512	return ENOSYS;
513}
514
515#endif	/* COREDUMP */
516