xref: /src/sys/kern/core_elf32.c

/*	$NetBSD: core_elf32.c,v 1.2 2001/12/10 01:52:26 thorpej Exp $	*/

/*
 * Copyright (c) 2001 Wasabi Systems, Inc.
 * All rights reserved.
 *
 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed for the NetBSD Project by
 *	Wasabi Systems, Inc.
 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
 *    or promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * core_elf32.c/core_elf64.c: Support for the Elf32/Elf64 core file format.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(1, "$NetBSD: core_elf32.c,v 1.2 2001/12/10 01:52:26 thorpej Exp $");

/* If not included by core_elf64.c, ELFSIZE won't be defined. */
#ifndef ELFSIZE
#define	ELFSIZE		32
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/exec_elf.h>
#include <sys/ptrace.h>

#include <machine/reg.h>

#include <uvm/uvm_extern.h>

struct countsegs_state {
	int	npsections;
};

int	ELFNAMEEND(coredump_countsegs)(struct proc *, struct vnode *,
	    struct ucred *, struct uvm_coredump_state *);

struct writesegs_state {
	off_t	offset;
	off_t	secoff;
};

int	ELFNAMEEND(coredump_writeseghdrs)(struct proc *, struct vnode *,
	    struct ucred *, struct uvm_coredump_state *);
int	ELFNAMEEND(coredump_writesegs)(struct proc *, struct vnode *,
	    struct ucred *, struct uvm_coredump_state *);

int	ELFNAMEEND(coredump_notes)(struct proc *, struct vnode *,
	    struct ucred *, int *, off_t);

#define	ELFROUNDSIZE	4	/* XXX Should it be sizeof(Elf_Word)? */
#define	elfround(x)	roundup((x), ELFROUNDSIZE)

int
ELFNAMEEND(coredump)(struct proc *p, struct vnode *vp, struct ucred *cred)
{
	Elf_Ehdr ehdr;
	Elf_Phdr phdr;
	struct countsegs_state cs;
	struct writesegs_state ws;
	off_t notestart, secstart;
	int notesize, error;

	/*
	 * We have to make a total of 3 passes across the map:
	 *
	 *	1. Count the number of map entries (the number of
	 *	   PT_LOAD sections).
	 *
	 *	2. Write the P-section headers.
	 *
	 *	3. Write the P-sections.
	 */

	/* Pass 1: count the entries. */
	cs.npsections = 0;
	error = uvm_coredump_walkmap(p, vp, cred,
	    ELFNAMEEND(coredump_countsegs), &cs);
	if (error)
		return (error);

	/* Get the size of the notes. */
	error = ELFNAMEEND(coredump_notes)(p, vp, cred, &notesize, 0);
	if (error)
		return (error);

	/* Count the PT_NOTE section. */
	cs.npsections++;

	memcpy(ehdr.e_ident, ELFMAG, SELFMAG);
#if ELFSIZE == 32
	ehdr.e_ident[EI_CLASS] = ELFCLASS32;
#elif ELFSIZE == 64
	ehdr.e_ident[EI_CLASS] = ELFCLASS64;
#endif
	ehdr.e_ident[EI_DATA] = ELFDEFNNAME(MACHDEP_ENDIANNESS);
	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
	/* XXX Should be the OSABI/ABI version of the executable. */
	ehdr.e_ident[EI_OSABI] = ELFOSABI_SYSV;
	ehdr.e_ident[EI_ABIVERSION] = 0;

	ehdr.e_type = ET_CORE;
	/* XXX This should be the e_machine of the executable. */
	ehdr.e_machine = ELFDEFNNAME(MACHDEP_ID);
	ehdr.e_version = EV_CURRENT;
	ehdr.e_entry = 0;
	ehdr.e_phoff = sizeof(ehdr);
	ehdr.e_shoff = 0;
	ehdr.e_flags = 0;
	ehdr.e_ehsize = sizeof(ehdr);
	ehdr.e_phentsize = sizeof(Elf_Phdr);
	ehdr.e_phnum = cs.npsections;
	ehdr.e_shentsize = 0;
	ehdr.e_shnum = 0;
	ehdr.e_shstrndx = 0;

	/* Write out the ELF header. */
	error = vn_rdwr(UIO_WRITE, vp, (caddr_t)&ehdr,
	    (int)sizeof(ehdr), (off_t)0,
	    UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, NULL, p);

	ws.offset = ehdr.e_phoff;
	notestart = ws.offset + (sizeof(phdr) * cs.npsections);
	secstart = round_page(notestart + notesize);

	/* Now write the P-section headers. */
	ws.secoff = secstart;
	error = uvm_coredump_walkmap(p, vp, cred,
	    ELFNAMEEND(coredump_writeseghdrs), &ws);
	if (error)
		return (error);

	/* Write out the PT_NOTE header. */
	phdr.p_type = PT_NOTE;
	phdr.p_offset = notestart;
	phdr.p_vaddr = 0;
	phdr.p_paddr = 0;
	phdr.p_filesz = notesize;
	phdr.p_memsz = 0;
	phdr.p_flags = PF_R;
	phdr.p_align = ELFROUNDSIZE;

	error = vn_rdwr(UIO_WRITE, vp,
	    (caddr_t)&phdr, sizeof(phdr),
	    ws.offset, UIO_SYSSPACE,
	    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
	if (error)
		return (error);

	ws.offset += sizeof(phdr);

#ifdef DIAGNOSTIC
	if (ws.offset != notestart)
		panic("coredump: offset %lld != notestart %lld",
		    ws.offset, notestart);
#endif

	/* Write out the notes. */
	error = ELFNAMEEND(coredump_notes)(p, vp, cred, &notesize, ws.offset);

	ws.offset += notesize;

#ifdef DIAGNOSTIC
	if (round_page(ws.offset) != secstart)
		panic("coredump: offset %lld != secstart %lld",
		    round_page(ws.offset), secstart);
#endif

	/* ...and finally, the sections themselves. */
	ws.secoff = secstart;
	error = uvm_coredump_walkmap(p, vp, cred,
	    ELFNAMEEND(coredump_writesegs), &ws);
	if (error)
		return (error);

	return (error);
}

int
ELFNAMEEND(coredump_countsegs)(struct proc *p, struct vnode *vp,
    struct ucred *cred, struct uvm_coredump_state *us)
{
	struct countsegs_state *cs = us->cookie;

	cs->npsections++;
	return (0);
}

int
ELFNAMEEND(coredump_writeseghdrs)(struct proc *p, struct vnode *vp,
    struct ucred *cred, struct uvm_coredump_state *us)
{
	struct writesegs_state *ws = us->cookie;
	Elf_Phdr phdr;
	vsize_t size;
	int error;

	size = us->end - us->start;

	phdr.p_type = PT_LOAD;
	phdr.p_offset = ws->secoff;
	phdr.p_vaddr = us->start;
	phdr.p_paddr = 0;
	phdr.p_filesz = (us->flags & UVM_COREDUMP_NODUMP) ? 0 : size;
	phdr.p_memsz = size;
	phdr.p_flags = 0;
	if (us->prot & VM_PROT_READ)
		phdr.p_flags |= PF_R;
	if (us->prot & VM_PROT_WRITE)
		phdr.p_flags |= PF_W;
	if (us->prot & VM_PROT_EXECUTE)
		phdr.p_flags |= PF_X;
	phdr.p_align = PAGE_SIZE;

	error = vn_rdwr(UIO_WRITE, vp,
	    (caddr_t)&phdr, sizeof(phdr),
	    ws->offset, UIO_SYSSPACE,
	    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
	if (error)
		return (error);

	ws->offset += sizeof(phdr);
	ws->secoff += phdr.p_filesz;

	return (0);
}

int
ELFNAMEEND(coredump_writesegs)(struct proc *p, struct vnode *vp,
    struct ucred *cred, struct uvm_coredump_state *us)
{
	struct writesegs_state *ws = us->cookie;
	vsize_t size;
	int error;

	if (us->flags & UVM_COREDUMP_NODUMP)
		return (0);

	size = us->end - us->start;

	error = vn_rdwr(UIO_WRITE, vp,
	    (caddr_t) us->start, size,
	    ws->secoff, UIO_USERSPACE,
	    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
	if (error)
		return (error);

	ws->secoff += size;

	return (0);
}

int
ELFNAMEEND(coredump_notes)(struct proc *p, struct vnode *vp,
    struct ucred *cred, int *sizep, off_t offset)
{
	struct netbsd_elfcore_procinfo cpi;
	Elf_Nhdr nhdr;
	int size, notesize, error;
	char name[64];
	int namesize;
	struct reg intreg;
#ifdef PT_GETFPREGS
	struct fpreg freg;
#endif

	size = 0;

	/* First, write an elfcore_procinfo. */
	notesize = sizeof(nhdr) + elfround(sizeof(ELF_NOTE_NETBSD_CORE_NAME)) +
	    elfround(sizeof(cpi));
	if (offset) {
		cpi.cpi_version = NETBSD_ELFCORE_PROCINFO_VERSION;
		cpi.cpi_cpisize = sizeof(cpi);
		cpi.cpi_signo = p->p_sigctx.ps_sig;
		cpi.cpi_sigcode = p->p_sigctx.ps_code;

		memcpy(&cpi.cpi_sigpend, &p->p_sigctx.ps_siglist,
		    sizeof(cpi.cpi_sigpend));
		memcpy(&cpi.cpi_sigmask, &p->p_sigctx.ps_sigmask,
		    sizeof(cpi.cpi_sigmask));
		memcpy(&cpi.cpi_sigignore, &p->p_sigctx.ps_sigignore,
		    sizeof(cpi.cpi_sigignore));
		memcpy(&cpi.cpi_sigcatch, &p->p_sigctx.ps_sigcatch,
		    sizeof(cpi.cpi_sigcatch));

		cpi.cpi_pid = p->p_pid;
		cpi.cpi_ppid = p->p_pptr->p_pid;
		cpi.cpi_pgrp = p->p_pgid;
		cpi.cpi_sid = p->p_session->s_sid;

		cpi.cpi_ruid = p->p_cred->p_ruid;
		cpi.cpi_euid = p->p_ucred->cr_uid;
		cpi.cpi_svuid = p->p_cred->p_svuid;

		cpi.cpi_rgid = p->p_cred->p_rgid;
		cpi.cpi_egid = p->p_ucred->cr_gid;
		cpi.cpi_svgid = p->p_cred->p_svgid;

		cpi.cpi_nlwps = 1;	/* XXX for now */
		strcpy(cpi.cpi_name, p->p_comm);

		nhdr.n_namesz = sizeof(ELF_NOTE_NETBSD_CORE_NAME);
		nhdr.n_descsz = sizeof(cpi);
		nhdr.n_type = ELF_NOTE_NETBSD_CORE_PROCINFO;

		error = ELFNAMEEND(coredump_writenote)(p, vp, cred, offset,
		    &nhdr, ELF_NOTE_NETBSD_CORE_NAME, &cpi);
		if (error)
			return (error);

		offset += notesize;
	}

	size += notesize;

	/* XXX Add hook for machdep per-proc notes. */

	/*
	 * Now, for each LWP, write the register info and any other
	 * per-LWP notes.
	 */
	do {
		/* XXX Only one LWP for now. */
		sprintf(name, "%s@%d", ELF_NOTE_NETBSD_CORE_NAME, 1);
		namesize = strlen(name) + 1;

		notesize = sizeof(nhdr) + elfround(namesize) +
		    elfround(sizeof(intreg));
		if (offset) {
			error = process_read_regs(p, &intreg);
			if (error)
				return (error);

			nhdr.n_namesz = namesize;
			nhdr.n_descsz = sizeof(intreg);
			nhdr.n_type = PT_GETREGS;

			error = ELFNAMEEND(coredump_writenote)(p, vp, cred,
			    offset, &nhdr, name, &intreg);
			if (error)
				return (error);

			offset += notesize;
		}
		size += notesize;

#ifdef PT_GETFPREGS
		notesize = sizeof(nhdr) + elfround(namesize) +
		    elfround(sizeof(freg));
		if (offset) {
			error = process_read_fpregs(p, &freg);
			if (error)
				return (error);

			nhdr.n_namesz = namesize;
			nhdr.n_descsz = sizeof(freg);
			nhdr.n_type = PT_GETFPREGS;

			error = ELFNAMEEND(coredump_writenote)(p, vp, cred,
			    offset, &nhdr, name, &freg);
			if (error)
				return (error);

			offset += notesize;
		}
		size += notesize;
#endif
		/* XXX Add hook for machdep per-LWP notes. */
	} while (/*CONSTCOND*/0);

	*sizep = size;
	return (0);
}

int
ELFNAMEEND(coredump_writenote)(struct proc *p, struct vnode *vp,
    struct ucred *cred, off_t offset, Elf_Nhdr *nhdr, const char *name,
    void *data)
{
	int error;

	error = vn_rdwr(UIO_WRITE, vp,
	    (caddr_t) nhdr, sizeof(*nhdr),
	    offset, UIO_SYSSPACE,
	    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
	if (error)
		return (error);

	offset += sizeof(*nhdr);

	error = vn_rdwr(UIO_WRITE, vp,
	    (caddr_t)name, nhdr->n_namesz,
	    offset, UIO_SYSSPACE,
	    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
	if (error)
		return (error);

	offset += elfround(nhdr->n_namesz);

	error = vn_rdwr(UIO_WRITE, vp,
	    data, nhdr->n_descsz,
	    offset, UIO_SYSSPACE,
	    IO_NODELOCKED|IO_UNIT, cred, NULL, p);

	return (error);
}